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Liu L, Wang J, Zheng X, Zhang Q. VPS28 regulates triglyceride synthesis via ubiquitination in bovine mammary epithelial cells. Sci Rep 2024; 14:31310. [PMID: 39732879 PMCID: PMC11682384 DOI: 10.1038/s41598-024-82774-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2024] [Accepted: 12/09/2024] [Indexed: 12/30/2024] Open
Abstract
VPS28 (vacuolar protein sorting 28) is a subunit of the endosomal sorting complexes required for transport (ESCRTs) and is involved in ubiquitination. Ubiquitination is a critical system for protein degradation in eukaryotes. Considering the recent findings on the role of ubiquitination in the regulation of lipid metabolism, we hypothesized that VPS28 might affect the expression of genes involved in milk fat synthesis. To test this hypothesis, we modulated VPS28 expression in the bovine mammary epithelial cell line (MAC-T) and measured the effects on triglyceride (TG) synthesis using lentivirus-mediated techniques. The results showed that VPS28 knockdown significantly upregulated the levels of the fatty acid transporter CD36 molecule (CD36) and adipose differentiation-related protein (ADFP), leading to increased TG and fatty acid production, along with elevated ubiquitin (UB) levels, while reducing proteasome activity. In contrast, VPS28 overexpression increased CD36 levels while not significantly affecting ADFP or TG levels, with a trend toward reduced lipid droplets and increased UB expression and proteasome activity. In addition, inhibition of the ubiquitin-proteasome system and the endosomal-lysosomal pathway using epoxomicin and chloroquine, respectively, further increased CD36, ADFP, and TG levels, thereby enhancing cell viability. These in vitro findings were validated in vivo in a mouse model, where VPS28 knockdown increased mammary CD36, ADFP, UB expression, TG content, and lipid droplets without pathological changes in mammary tissue or blood TG alterations. These results confirm the pivotal role of VPS28 in regulating TG synthesis via the ubiquitination pathway, offering novel insights into the molecular mechanisms of milk fat production in a bovine cell model.
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Affiliation(s)
- Lily Liu
- College of Biological and Food Engineering, Southwest Forestry University, Kunming, 650224, China.
- The Roslin Institute, University of Edinburgh, Edinburgh, EH25 9RG, UK.
| | - Jinhai Wang
- The Roslin Institute, University of Edinburgh, Edinburgh, EH25 9RG, UK
| | - Xianrui Zheng
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, 230036, China
| | - Qin Zhang
- College of Animal Science and Technology, Shandong Agricultural University, Tai'an, 271018, China.
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2
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Wang Y, Zhou J, Yang Q, Li X, Qiu Y, Zhang Y, Liu M, Zhu AJ. Therapeutic siRNA targeting PLIN2 ameliorates steatosis, inflammation, and fibrosis in steatotic liver disease models. J Lipid Res 2024; 65:100635. [PMID: 39187042 PMCID: PMC11440260 DOI: 10.1016/j.jlr.2024.100635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 07/10/2024] [Accepted: 08/13/2024] [Indexed: 08/28/2024] Open
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent chronic liver disease worldwide. If left untreated, MASLD can progress from simple hepatic steatosis to metabolic dysfunction-associated steatohepatitis, which is characterized by inflammation and fibrosis. Current treatment options for MASLD remain limited, leaving substantial unmet medical needs for innovative therapeutic approaches. Here, we show that PLIN2, a lipid droplet protein inhibiting hepatic lipolysis, serves as a promising therapeutic target for MASLD. Hepatic PLIN2 levels were markedly elevated in multiple MASLD mouse models induced by diverse nutritional and genetic factors. The liver-specific deletion of Plin2 exhibited significant anti-MASLD effects in these models. To translate this discovery into a therapeutic application, we developed a GalNAc-siRNA conjugate with enhanced stabilization chemistry and validated its potent and sustained efficacy in suppressing Plin2 expression in mouse livers. This siRNA therapeutic, named GalNAc-siPlin2, was shown to be biosafe in mice. Treatment with GalNAc-siPlin2 for 6-8 weeks led to a decrease in hepatic triglyceride levels by approximately 60% in high-fat diet- and obesity-induced MASLD mouse models, accompanied with increased hepatic secretion of VLDL-triglyceride and enhanced thermogenesis in brown adipose tissues. Eight-week treatment with GalNAc-siPlin2 significantly improved hepatic steatosis, inflammation, and fibrosis in high-fat/high fructose-induced metabolic dysfunction-associated steatohepatitis models compared to control group. As a proof of concept, we developed a GalNAc-siRNA therapeutic targeting human PLIN2, which effectively suppressed hepatic PLIN2 expression and ameliorated MASLD in humanized PLIN2 knockin mice. Together, our results highlight the potential of GalNAc-siPLIN2 as a candidate MASLD therapeutic for clinical trials.
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Affiliation(s)
- Yao Wang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Jiaxin Zhou
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Qi Yang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China
| | - Xinmeng Li
- Institute of Molecular Medicine, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, College of Future Technology, Peking University, Beijing, China
| | - Yifu Qiu
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China; Institute of Molecular Medicine, Beijing Key Laboratory of Cardiometabolic Molecular Medicine, College of Future Technology, Peking University, Beijing, China
| | - Yansong Zhang
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China; Peking University Chengdu Academy for Advanced Interdisciplinary Biotechnologies, Chengdu, Sichuan, China.
| | - Min Liu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China.
| | - Alan Jian Zhu
- Ministry of Education Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Peking University, Beijing, China; Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China; Peking University Chengdu Academy for Advanced Interdisciplinary Biotechnologies, Chengdu, Sichuan, China.
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3
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Ibayashi M, Tatsumi T, Tsukamoto S. Perilipin2 depletion causes lipid droplet enlargement in the ovarian corpus luteum in mice. J Reprod Dev 2024; 70:296-302. [PMID: 39010158 PMCID: PMC11461514 DOI: 10.1262/jrd.2024-023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 06/17/2024] [Indexed: 07/17/2024] Open
Abstract
Lipid droplets (LDs) are endoplasmic reticulum-derived organelles that store neutral lipids (mostly triglycerides and cholesterol esters) within a phospholipid monolayer and appear in most eukaryotic cells. Perilipins (PLINs, comprising PLIN1-5) are abundant LD-associated proteins with highly variable expression levels among tissues. Although PLINs are expressed in the mammalian ovaries, little is known about their subcellular localization and physiological functions. In this study, we investigated the localization of PLIN1-3 and their relationship with LD synthesis using mCherry-HPos reporter mice, thereby enabling the visualization of LD biogenesis in vivo. PLIN2 and PLIN3 were localized as puncta in granulosa cells with low levels of LD synthesis in developing follicles. This localization pattern was quite different from that of PLIN1, which was mainly localized in the theca and interstitial cells with high levels of LD synthesis. In the corpus luteum, where LD synthesis is highly induced, PLIN2 and PLIN3 are abundant in the particulate structures, whereas PLIN1 is poorly distributed. We also generated global Plin2-deficient mice using the CRSPR/Cas9 system and demonstrated that the lack of PLIN2 did not alter the distribution of PLIN1 and PLIN3 but unexpectedly induced LD enlargement in the corpus luteum. Collectively, our results suggest that the localization of PLIN1-3 is spatiotemporally regulated and that PLIN2 deficiency influences LD mobilization in the corpus luteum within the ovaries.
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Affiliation(s)
- Megumi Ibayashi
- Laboratory Animal and Bioresource Sciences Section, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Takayuki Tatsumi
- Division of Reproductive Medicine, Center of Maternal-Fetal, Neonatal and Reproductive Medicine, National Center for Child Health and Development, Tokyo 157-8535, Japan
| | - Satoshi Tsukamoto
- Laboratory Animal and Bioresource Sciences Section, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
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4
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Dobariya P, Xie W, Rao SP, Xie J, Seelig DM, Vince R, Lee MK, More SS. Deletion of Glyoxalase 1 Exacerbates Acetaminophen-Induced Hepatotoxicity in Mice. Antioxidants (Basel) 2024; 13:648. [PMID: 38929087 PMCID: PMC11200933 DOI: 10.3390/antiox13060648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/19/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024] Open
Abstract
Acetaminophen (APAP) overdose triggers a cascade of intracellular oxidative stress events, culminating in acute liver injury. The clinically used antidote, N-acetylcysteine (NAC), has a narrow therapeutic window, and early treatment is essential for a satisfactory therapeutic outcome. For more versatile therapies that can be effective even at late presentation, the intricacies of APAP-induced hepatotoxicity must be better understood. Accumulation of advanced glycation end products (AGEs) and the consequent activation of the receptor for AGEs (RAGE) are considered one of the key mechanistic features of APAP toxicity. Glyoxalase 1 (Glo-1) regulates AGE formation by limiting the levels of methylglyoxal (MEG). In this study, we studied the relevance of Glo-1 in the APAP-mediated activation of RAGE and downstream cell death cascades. Constitutive Glo-1-knockout mice (GKO) and a cofactor of Glo-1, ψ-GSH, were used as tools. Our findings showed elevated oxidative stress resulting from the activation of RAGE and hepatocyte necrosis through steatosis in GKO mice treated with high-dose APAP compared to wild-type controls. A unique feature of the hepatic necrosis in GKO mice was the appearance of microvesicular steatosis as a result of centrilobular necrosis, rather than the inflammation seen in the wild type. The GSH surrogate and general antioxidant ψ-GSH alleviated APAP toxicity irrespective of the Glo-1 status, suggesting that oxidative stress is the primary driver of APAP toxicity. Overall, the exacerbation of APAP hepatotoxicity in GKO mice suggests the importance of this enzyme system in antioxidant defense against the initial stages of APAP overdose.
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Affiliation(s)
- Prakashkumar Dobariya
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
| | - Wei Xie
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
| | - Swetha Pavani Rao
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
| | - Jiashu Xie
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
| | - Davis M. Seelig
- Comparative Pathology Shared Resource, Masonic Cancer Center, University of Minnesota, St. Paul, MN 55108, USA;
- College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA
| | - Robert Vince
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
| | - Michael K. Lee
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA;
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Swati S. More
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA; (P.D.); (W.X.); (S.P.R.); (J.X.); (R.V.)
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5
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Chiariello A, Rossetti L, Valente S, Pasquinelli G, Sollazzo M, Iommarini L, Porcelli AM, Tognocchi M, Conte G, Santoro A, Kwiatkowska KM, Garagnani P, Salvioli S, Conte M. Downregulation of PLIN2 in human dermal fibroblasts impairs mitochondrial function in an age-dependent fashion and induces cell senescence via GDF15. Aging Cell 2024; 23:e14111. [PMID: 38650174 PMCID: PMC11113257 DOI: 10.1111/acel.14111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/29/2024] [Accepted: 01/31/2024] [Indexed: 04/25/2024] Open
Abstract
Perilipin 2 (PLIN2) is a lipid droplet (LD)-coating protein playing important roles in lipid homeostasis and suppression of lipotoxicity in different tissues and cell types. Recently, a role for PLIN2 in supporting mitochondrial function has emerged. PLIN2 dysregulation is involved in many metabolic disorders and age-related diseases. However, the exact consequences of PLIN2 dysregulation are not yet completely understood. In this study, we knocked down (KD) PLIN2 in primary human dermal fibroblasts (hDFs) from young (mean age 29 years) and old (mean age 71 years) healthy donors. We have found that PLIN2 KD caused a decline of mitochondrial function only in hDFs from young donors, while mitochondria of hDFs from old donors (that are already partially impaired) did not significantly worsen upon PLIN2 KD. This mitochondrial impairment is associated with the increased expression of the stress-related mitokine growth differentiation factor 15 (GDF15) and the induction of cell senescence. Interestingly, the simultaneous KD of PLIN2 and GDF15 abrogated the induction of cell senescence, suggesting that the increase in GDF15 is the mediator of this phenomenon. Moreover, GDF15 KD caused a profound alteration of gene expression, as observed by RNA-Seq analysis. After a more stringent analysis, this alteration remained statistically significant only in hDFs from young subjects, further supporting the idea that cells from old and young donors react differently when undergoing manipulation of either PLIN2 or GDF15 genes, with the latter being likely a downstream mediator of the former.
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Affiliation(s)
- Antonio Chiariello
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
| | - Luca Rossetti
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
- Interdepartmental Centre “Alma Mater Research Institute on Global Challenges and Climate Change (Alma Climate)”University of BolognaBolognaItaly
| | - Sabrina Valente
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
| | - Gianandrea Pasquinelli
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
- IRCCS Azienda Ospedaliero‐Universitaria di BolognaBolognaItaly
| | - Manuela Sollazzo
- Department of Pharmacy and Biotechnology (FABIT)University of BolognaBolognaItaly
| | - Luisa Iommarini
- Department of Pharmacy and Biotechnology (FABIT)University of BolognaBolognaItaly
| | - Anna Maria Porcelli
- Department of Pharmacy and Biotechnology (FABIT)University of BolognaBolognaItaly
| | - Monica Tognocchi
- Department of Agriculture, Food and EnvironmentUniversity of PisaPisaItaly
| | - Giuseppe Conte
- Department of Agriculture, Food and EnvironmentUniversity of PisaPisaItaly
| | - Aurelia Santoro
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
| | | | - Paolo Garagnani
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
- IRCCS Azienda Ospedaliero‐Universitaria di BolognaBolognaItaly
| | - Stefano Salvioli
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
- IRCCS Azienda Ospedaliero‐Universitaria di BolognaBolognaItaly
| | - Maria Conte
- Department of Medical and Surgical Sciences (DIMEC)University of BolognaBolognaItaly
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6
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Tzur Y, Winek K, Madrer N, Dubnov S, Bennett ER, Greenberg DS, Hanin G, Gammal A, Tam J, Arkin IT, Paldor I, Soreq H. Lysine tRNA fragments and miR-194-5p co-regulate hepatic steatosis via β-Klotho and perilipin 2. Mol Metab 2024; 79:101856. [PMID: 38141848 PMCID: PMC10805669 DOI: 10.1016/j.molmet.2023.101856] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/20/2023] [Accepted: 12/17/2023] [Indexed: 12/25/2023] Open
Abstract
OBJECTIVE Non-alcoholic fatty liver disease (NAFLD) involves hepatic accumulation of intracellular lipid droplets via incompletely understood processes. Here, we report distinct and cooperative NAFLD roles of LysTTT-5'tRF transfer RNA fragments and microRNA miR-194-5p. METHODS Combined use of diet induced obese mice with human-derived oleic acid-exposed Hep G2 cells revealed new NAFLD roles of LysTTT-5'tRF and miR-194-5p. RESULTS Unlike lean animals, dietary-induced NAFLD mice showed concurrent hepatic decrease of both LysTTT-5'tRF and miR-194-5p levels, which were restored following miR-132 antisense oligonucleotide treatment which suppresses hepatic steatosis. Moreover, exposing human-derived Hep G2 cells to oleic acid for 7 days co-suppressed miR-194-5p and LysTTT-5'tRF levels while increasing lipid accumulation. Inversely, transfecting fattened cells with a synthetic LysTTT-5'tRF mimic elevated mRNA levels of the metabolic regulator β-Klotho while decreasing triglyceride amounts by 30% within 24 h. In contradistinction, antisense suppression of miR-194-5p induced accumulation of its novel target, the NAFLD-implicated lipid droplet-coating PLIN2 protein. Further, two out of 15 steatosis-alleviating screened drug-repurposing compounds, Danazol and Latanoprost, elevated miR-194-5p or LysTTT-5'tRF levels. CONCLUSION Our findings highlight the different yet complementary roles of miR-194-5p and LysTTT-5'tRF and offer new insights into the complex roles of small non-coding RNAs and the multiple pathways involved in NAFLD pathogenesis.
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Affiliation(s)
- Yonat Tzur
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Katarzyna Winek
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel; The Edmond and Lily Safra Center of Brain Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Nimrod Madrer
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Serafima Dubnov
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel; The Edmond and Lily Safra Center of Brain Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Estelle R Bennett
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - David S Greenberg
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Geula Hanin
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Asaad Gammal
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Joseph Tam
- Obesity and Metabolism Laboratory, The Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Isaiah T Arkin
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel
| | - Iddo Paldor
- Shaare Zedek Medical Center, The Neurosurgery Department, Main Building, 10th Floor, 12 Shmu'el Bait Street, Jerusalem, 9103102 Israel
| | - Hermona Soreq
- The Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel; The Edmond and Lily Safra Center of Brain Science, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel.
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7
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Doncheva AI, Li Y, Khanal P, Hjorth M, Kolset SO, Norheim FA, Kimmel AR, Dalen KT. Altered hepatic lipid droplet morphology and lipid metabolism in fasted Plin2-null mice. J Lipid Res 2023; 64:100461. [PMID: 37844775 PMCID: PMC10716011 DOI: 10.1016/j.jlr.2023.100461] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 10/04/2023] [Accepted: 10/05/2023] [Indexed: 10/18/2023] Open
Abstract
Perilipin 2 (Plin2) binds to the surface of hepatic lipid droplets (LDs) with expression levels that correlate with triacylglyceride (TAG) content. We investigated if Plin2 is important for hepatic LD storage in fasted or high-fat diet-induced obese Plin2+/+ and Plin2-/- mice. Plin2-/- mice had comparable body weights, metabolic phenotype, glucose tolerance, and circulating TAG and total cholesterol levels compared with Plin2+/+ mice, regardless of the dietary regime. Both fasted and high-fat fed Plin2-/- mice stored reduced levels of hepatic TAG compared with Plin2+/+ mice. Fasted Plin2-/- mice stored fewer but larger hepatic LDs compared with Plin2+/+ mice. Detailed hepatic lipid analysis showed substantial reductions in accumulated TAG species in fasted Plin2-/- mice compared with Plin2+/+ mice, whereas cholesteryl esters and phosphatidylcholines were increased. RNA-Seq revealed minor differences in hepatic gene expression between fed Plin2+/+ and Plin2-/- mice, in contrast to marked differences in gene expression between fasted Plin2+/+ and Plin2-/- mice. Our findings demonstrate that Plin2 is required to regulate hepatic LD size and storage of neutral lipid species in the fasted state, while its role in obesity-induced steatosis is less clear.
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Affiliation(s)
- Atanaska I Doncheva
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Yuchuan Li
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Hepato-Pancreato-Biliary Surgery, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Prabhat Khanal
- Faculty of Biosciences and Aquaculture, Nord University, Steinkjer, Norway
| | - Marit Hjorth
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Svein O Kolset
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Frode A Norheim
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Alan R Kimmel
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, The National Institutes of Health, Bethesda, MD, USA
| | - Knut Tomas Dalen
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway; The Norwegian Transgenic Center, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
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8
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Hu Y, Wang R, Liu J, Wang Y, Dong J. Lipid droplet deposition in the regenerating liver: A promoter, inhibitor, or bystander? Hepatol Commun 2023; 7:e0267. [PMID: 37708445 PMCID: PMC10503682 DOI: 10.1097/hc9.0000000000000267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 07/29/2023] [Indexed: 09/16/2023] Open
Abstract
Liver regeneration (LR) is a complex process involving intricate networks of cellular connections, cytokines, and growth factors. During the early stages of LR, hepatocytes accumulate lipids, primarily triacylglycerol, and cholesterol esters, in the lipid droplets. Although it is widely accepted that this phenomenon contributes to LR, the impact of lipid droplet deposition on LR remains a matter of debate. Some studies have suggested that lipid droplet deposition has no effect or may even be detrimental to LR. This review article focuses on transient regeneration-associated steatosis and its relationship with the liver regenerative response.
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Affiliation(s)
- Yuelei Hu
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Ruilin Wang
- Department of Cadre’s Wards Ultrasound Diagnostics. Ultrasound Diagnostic Center, The First Hospital of Jilin University, Jilin University, Changchun, China
| | - Juan Liu
- Research Unit of Precision Hepatobiliary Surgery Paradigm, Chinese Academy of Medical Sciences, Beijing, China
- Hepatopancreatobiliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
- Institute for Organ Transplant and Bionic Medicine, Tsinghua University, Beijing, China
- Clinical Translational Science Center, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing, China
| | - Yunfang Wang
- Research Unit of Precision Hepatobiliary Surgery Paradigm, Chinese Academy of Medical Sciences, Beijing, China
- Hepatopancreatobiliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
- Institute for Organ Transplant and Bionic Medicine, Tsinghua University, Beijing, China
- Clinical Translational Science Center, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing, China
| | - Jiahong Dong
- Department of Hepatobiliary and Pancreatic Surgery, The First Hospital of Jilin University, Jilin University, Changchun, China
- Research Unit of Precision Hepatobiliary Surgery Paradigm, Chinese Academy of Medical Sciences, Beijing, China
- Hepatopancreatobiliary Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
- Institute for Organ Transplant and Bionic Medicine, Tsinghua University, Beijing, China
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9
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Delmas D, Cotte AK, Connat JL, Hermetet F, Bouyer F, Aires V. Emergence of Lipid Droplets in the Mechanisms of Carcinogenesis and Therapeutic Responses. Cancers (Basel) 2023; 15:4100. [PMID: 37627128 PMCID: PMC10452604 DOI: 10.3390/cancers15164100] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/04/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Cancer shares common risk factors with cardiovascular diseases such as dyslipidemia, obesity and inflammation. In both cases, dysregulations of lipid metabolism occur, and lipid vesicles emerge as important factors that can influence carcinogenesis. In this review, the role of different lipids known to be involved in cancer and its response to treatments is detailed. In particular, lipid droplets (LDs), initially described for their role in lipid storage, exert multiple functions, from the physiological prevention of LD coalescence and regulation of endoplasmic reticulum homeostasis to pathological involvement in tumor progression and aggressiveness. Analysis of LDs highlights the importance of phosphatidylcholine metabolism and the diversity of lipid synthesis enzymes. In many cancers, the phosphatidylcholine pathways are disrupted, modifying the expression of genes coding for metabolic enzymes. Tumor microenvironment conditions, such as hypoxia, different types of stress or inflammatory conditions, are also important determinants of LD behavior in cancer cells. Therefore, LDs represent therapeutic targets in cancer, and many lipid mediators have emerged as potential biomarkers for cancer onset, progression, and/or resistance.
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Affiliation(s)
- Dominique Delmas
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
- Centre de Lutte Contre le Cancer Georges François Leclerc, 21000 Dijon, France
| | - Alexia K. Cotte
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
| | - Jean-Louis Connat
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
| | - François Hermetet
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
| | - Florence Bouyer
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
| | - Virginie Aires
- UFR of Heatlh Sciences, Université de Bourgogne, 21000 Dijon, France; (A.K.C.); (J.-L.C.); (F.H.); (F.B.); (V.A.)
- INSERM Research Center U1231—Bioactive Molecules and Health Research Group, Cancer and Adaptive Immune Response Team, 21000 Dijon, France
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10
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Guo X, Zhou Q, Jin J, Lan F, Wen C, Li J, Yang N, Sun C. Hepatic steatosis is associated with dysregulated cholesterol metabolism and altered protein acetylation dynamics in chickens. J Anim Sci Biotechnol 2023; 14:108. [PMID: 37568219 PMCID: PMC10422840 DOI: 10.1186/s40104-023-00910-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 06/28/2023] [Indexed: 08/13/2023] Open
Abstract
BACKGROUND Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed to systematically investigate the genetic regulatory mechanisms of hepatic steatosis in laying hens. METHODS Ninety individuals with the most prominent characteristics were selected from 686 laying hens according to the accumulation of lipid droplets in the liver, and were graded into three groups, including the control, mild hepatic steatosis and severe hepatic steatosis groups. A combination of transcriptome, proteome, acetylome and lipidome analyses, along with bioinformatics analysis were used to screen the key biological processes, modifications and lipids associated with hepatic steatosis. RESULTS The rationality of the hepatic steatosis grouping was verified through liver biochemical assays and RNA-seq. Hepatic steatosis was characterized by increased lipid deposition and multiple metabolic abnormalities. Integration of proteome and acetylome revealed that differentially expressed proteins (DEPs) interacted with differentially acetylated proteins (DAPs) and were involved in maintaining the metabolic balance in the liver. Acetylation alterations mainly occurred in the progression from mild to severe hepatic steatosis, i.e., the enzymes in the fatty acid oxidation and bile acid synthesis pathways were significantly less acetylated in severe hepatic steatosis group than that in mild group (P < 0.05). Lipidomics detected a variety of sphingolipids (SPs) and glycerophospholipids (GPs) were negatively correlated with hepatic steatosis (r ≤ -0.5, P < 0.05). Furthermore, the severity of hepatic steatosis was associated with a decrease in cholesterol and bile acid synthesis and an increase in exogenous cholesterol transport. CONCLUSIONS In addition to acquiring a global and thorough picture of hepatic steatosis in laying hens, we were able to reveal the role of acetylation in hepatic steatosis and depict the changes in hepatic cholesterol metabolism. The findings provides a wealth of information to facilitate a deeper understanding of the pathophysiology of fatty liver and contributes to the development of therapeutic strategies.
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Affiliation(s)
- Xiaoli Guo
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Qianqian Zhou
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Jiaming Jin
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Fangren Lan
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Chaoliang Wen
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Junying Li
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Ning Yang
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Congjiao Sun
- National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
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11
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Wei X, Lin L, Yuan QQ, Wang XY, Zhang Q, Zhang XM, Tang KC, Guo MY, Dong TY, Han W, Huang DK, Qi YL, Zhang M, Zhang HB. Bavachin protects against diet-induced hepatic steatosis and obesity in mice. Acta Pharmacol Sin 2023; 44:1416-1428. [PMID: 36721007 PMCID: PMC10310714 DOI: 10.1038/s41401-023-01056-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 01/13/2023] [Indexed: 02/02/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a major health concern worldwide, and the incidence of metabolic disorders associated with NAFLD is rapidly increasing because of the obesity epidemic. There are currently no approved drugs that prevent or treat NAFLD. Recent evidence shows that bavachin, a flavonoid isolated from the seeds and fruits of Psoralea corylifolia L., increases the transcriptional activity of PPARγ and insulin sensitivity during preadipocyte differentiation, but the effect of bavachin on glucose and lipid metabolism remains unclear. In the current study we investigated the effects of bavachin on obesity-associated NAFLD in vivo and in vitro. In mouse primary hepatocytes and Huh7 cells, treatment with bavachin (20 μM) significantly suppressed PA/OA or high glucose/high insulin-induced increases in the expression of fatty acid synthesis-related genes and the number and size of lipid droplets. Furthermore, bavachin treatment markedly elevated the phosphorylation levels of AKT and GSK-3β, improving the insulin signaling activity in the cells. In HFD-induced obese mice, administration of bavachin (30 mg/kg, i.p. every other day for 8 weeks) efficiently attenuated the increases in body weight, liver weight, blood glucose, and liver and serum triglyceride contents. Moreover, bavachin administration significantly alleviated hepatic inflammation and ameliorated HFD-induced glucose intolerance and insulin resistance. We demonstrated that bavachin protected against HFD-induced obesity by inducing fat thermogenesis and browning subcutaneous white adipose tissue (subWAT). We revealed that bavachin repressed the expression of lipid synthesis genes in the liver of obese mice, while promoting the expression of thermogenesis, browning, and mitochondrial respiration-related genes in subWAT and brown adipose tissue (BAT) in the mice. In conclusion, bavachin attenuates hepatic steatosis and obesity by repressing de novo lipogenesis, inducing fat thermogenesis and browning subWAT, suggesting that bavachin is a potential drug for NAFLD therapy.
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Affiliation(s)
- Xiang Wei
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
- Department of Hyperbaric Oxygen, The Second People's Hospital of Hefei, Hefei Hospital Affiliated to Anhui Medical University, Hefei, 230011, China
| | - Li Lin
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Qian-Qian Yuan
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Xiu-Yun Wang
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Qing Zhang
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Xiao-Min Zhang
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Ke-Chao Tang
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Man-Yu Guo
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China
| | - Ting-Yu Dong
- The Second Clinical Medical College of Anhui Medical University, Hefei, 230032, China
| | - Wei Han
- Department of Gastroenterology, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, China
| | - Da-Ke Huang
- Synthetic Laboratory of School of Basic Medicine Sciences, Anhui Medical University, Hefei, 230032, China
| | - Yin-Liang Qi
- Department of Hyperbaric Oxygen, The Second People's Hospital of Hefei, Hefei Hospital Affiliated to Anhui Medical University, Hefei, 230011, China
| | - Mei Zhang
- Health Management Center, The First Affiliated Hospital of the University of Sciences and Technology of China (Anhui Provincial Hospital), Hefei, 230001, China.
| | - Hua-Bing Zhang
- Department of Biochemistry and Molecular Biology, Metabolic Disease Research Center, School of Basic Medicine, Anhui Medical University, Hefei, 230032, China.
- The Affiliated Chuzhou Hospital of Anhui Medical University (The First People's Hospital of Chuzhou), Chuzhou, 239001, China.
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12
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Che L, Huang J, Lin JX, Xu CY, Wu XM, Du ZB, Wu JS, Lin ZN, Lin YC. Aflatoxin B1 exposure triggers hepatic lipotoxicity via p53 and perilipin 2 interaction-mediated mitochondria-lipid droplet contacts: An in vitro and in vivo assessment. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130584. [PMID: 37055989 DOI: 10.1016/j.jhazmat.2022.130584] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 11/17/2022] [Accepted: 12/07/2022] [Indexed: 06/19/2023]
Abstract
Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins widely found in food contaminants, and its target organ is the liver. It poses a major food security and public health threat worldwide. However, the lipotoxicity mechanism of AFB1 exposure-induced liver injury remains unclear and requires further elucidation. Herein, we investigated the potential hepatic lipotoxicity of AFB1 exposure using in vitro and in vivo models to assess the public health hazards of high dietary AFB1 exposure. We demonstrated that low-dose of AFB1 (1.25 μM for 48 h, about one-fifth of the IC50 in HepG2 and HepaRG cells, IC50 are 5.995 μM and 5.266 μM, respectively) exposure significantly induced hepatic lipotoxicity, including abnormal lipid droplets (LDs) growth, mitochondria-LDs contacts increase, lipophagy disruption, and lipid accumulation. Mechanistically, we showed that AFB1 exposure promoted the mitochondrial p53 (mito-p53) and LDs-associated protein perilipin 2 (PLIN2) interaction-mediated mitochondria-LDs contacts, resulting in lipid accumulation in hepatocytes. Mito-p53-targeted inhibition, knockdown of PLIN2, and rapamycin application efficiently promoted the lysosome-dependent lipophagy and alleviated the hepatic lipotoxicity and liver injury induced by AFB1 exposure. Overall, our study found that mito-p53 and PLIN2 interaction mediates three organelles-mitochondria, LDs, and lysosomal networks to regulate lipid homeostasis in AFB1 exposure-induced hepatotoxicity, revealing how this unique trio of organelles works together and provides a novel insight into the targeted intervention in inter-organelle lipid sensing and trafficking for alleviating hazardous materials-induced hepatic lipotoxicity.
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Affiliation(s)
- Lin Che
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jing Huang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jin-Xian Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Chi-Yu Xu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Xin-Mou Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Ze-Bang Du
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Jia-Shen Wu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Zhong-Ning Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Yu-Chun Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen 361102, China.
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13
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Kim KE, Lee J, Shin HJ, Jeong EA, Jang HM, Ahn YJ, An HS, Lee JY, Shin MC, Kim SK, Yoo WG, Kim WH, Roh GS. Lipocalin-2 activates hepatic stellate cells and promotes nonalcoholic steatohepatitis in high-fat diet-fed Ob/Ob mice. Hepatology 2023; 77:888-901. [PMID: 35560370 PMCID: PMC9936980 DOI: 10.1002/hep.32569] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/19/2022] [Accepted: 05/08/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND AIMS In obesity and type 2 diabetes mellitus, leptin promotes insulin resistance and contributes to the progression of NASH via activation of hepatic stellate cells (HSCs). However, the pathogenic mechanisms that trigger HSC activation in leptin-deficient obesity are still unknown. This study aimed to determine how HSC-targeting lipocalin-2 (LCN2) mediates the transition from simple steatosis to NASH. APPROACH AND RESULTS Male wild-type (WT) and ob/ob mice were fed a high-fat diet (HFD) for 20 weeks to establish an animal model of NASH with fibrosis. Ob/ob mice were subject to caloric restriction or recombinant leptin treatment. Double knockout (DKO) mice lacking both leptin and lcn2 were also fed an HFD for 20 weeks. In addition, HFD-fed ob/ob mice were treated with gadolinium trichloride to deplete Kupffer cells. The LX-2 human HSCs and primary HSCs from ob/ob mice were used to investigate the effects of LCN2 on HSC activation. Serum and hepatic LCN2 expression levels were prominently increased in HFD-fed ob/ob mice compared with normal diet-fed ob/ob mice or HFD-fed WT mice, and these changes were closely linked to liver fibrosis and increased hepatic α-SMA/matrix metalloproteinase 9 (MMP9)/signal transducer and activator of transcription 3 (STAT3) protein levels. HFD-fed DKO mice showed a marked reduction of α-SMA protein compared with HFD-fed ob/ob mice. In particular, the colocalization of LCN2 and α-SMA was increased in HSCs from HFD-fed ob/ob mice. In primary HSCs from ob/ob mice, exogenous LCN2 treatment induced HSC activation and MMP9 secretion. By contrast, LCN2 receptor 24p3R deficiency or a STAT3 inhibitor reduced the activation and migration of primary HSCs. CONCLUSIONS LCN2 acts as a key mediator of HSC activation in leptin-deficient obesity via α-SMA/MMP9/STAT3 signaling, thereby exacerbating NASH.
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Affiliation(s)
- Kyung Eun Kim
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Jaewoong Lee
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Hyun Joo Shin
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Eun Ae Jeong
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Hye Min Jang
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Yu Jeong Ahn
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Hyeong Seok An
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Jong Youl Lee
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Meong Cheol Shin
- College of Pharmacy, Research Institute of Pharmaceutical Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Soo Kyoung Kim
- Department of Internal Medicine, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Won Gi Yoo
- Department of Parasitology and Tropical Medicine, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Won Ho Kim
- Division of Cardiovascular Diseases, Center for Biomedical Sciences, Korea National Institute of Health, Cheongju, Republic of Korea
| | - Gu Seob Roh
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Health Sciences, Gyeongsang National University, Jinju, Republic of Korea
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14
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Bao X, Ma X, Huang R, Chen J, Xin H, Zhou M, Li L, Tong S, Zhang Q, Shui G, Deng F, Yu L, Li MD, Zhang Z. Knockdown of hepatocyte Perilipin-3 mitigates hepatic steatosis and steatohepatitis caused by hepatocyte CGI-58 deletion in mice. J Mol Cell Biol 2022; 14:mjac055. [PMID: 36107452 PMCID: PMC9929509 DOI: 10.1093/jmcb/mjac055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 06/12/2022] [Accepted: 09/13/2022] [Indexed: 11/12/2022] Open
Abstract
Comparative gene identification-58 (CGI-58), also known as α/β hydrolase domain containing 5, is the co-activator of adipose triglyceride lipase that hydrolyzes triglycerides stored in the cytosolic lipid droplets. Mutations in CGI-58 gene cause Chanarin-Dorfman syndrome (CDS), an autosomal recessive neutral lipid storage disease with ichthyosis. The liver pathology of CDS manifests as steatosis and steatohepatitis, which currently has no effective treatments. Perilipin-3 (Plin3) is a member of the Perilipin-ADRP-TIP47 protein family that is essential for lipid droplet biogenesis. The objective of this study was to test a hypothesis that deletion of a major lipid droplet protein alleviates fatty liver pathogenesis caused by CGI-58 deficiency in hepatocytes. Adult CGI-58-floxed mice were injected with adeno-associated vectors simultaneously expressing the Cre recombinase and microRNA against Plin3 under the control of a hepatocyte-specific promoter, followed by high-fat diet feeding for 6 weeks. Liver and blood samples were then collected from these animals for histological and biochemical analysis. Plin3 knockdown in hepatocytes prevented steatosis, steatohepatitis, and necroptosis caused by hepatocyte CGI-58 deficiency. Our work is the first to show that inhibiting Plin3 in hepatocytes is sufficient to mitigate hepatocyte CGI-58 deficiency-induced hepatic steatosis and steatohepatitis in mice.
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Affiliation(s)
- Xinyu Bao
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Xiaogen Ma
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Rongfeng Huang
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Jianghui Chen
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
- Department of Cardiology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Haoran Xin
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Meiyu Zhou
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Lihua Li
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Shifei Tong
- Department of Cardiology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing 401120, China
| | - Qian Zhang
- Department of General Medicine, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fang Deng
- Department of Pathophysiology, College of High Altitude Military Medicine, Army Medical University, Chongqing 400038, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Chongqing 400038, China
- Key Laboratory of High Altitude Medicine, PLA, Chongqing 400038, China
| | - Liqing Yu
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Min-Dian Li
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
| | - Zhihui Zhang
- Department of Cardiovascular Medicine, Center for Circadian Metabolism and Cardiovascular Disease, Southwest Hospital, Army Medical University, Chongqing 400038, China
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15
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PNPLA3(I148M) Inhibits Lipolysis by Perilipin-5-Dependent Competition with ATGL. Cells 2022; 12:cells12010073. [PMID: 36611868 PMCID: PMC9818421 DOI: 10.3390/cells12010073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
The single nucleotide polymorphism I148M of the lipase patatin-like phospholipase domain containing 3 (PNPLA3) is associated with an unfavorable prognosis in alcoholic and non-alcoholic steatohepatitis (ASH, NASH), with progression to liver cirrhosis and development of hepatocellular carcinoma. In this study, we investigated the mechanistic interaction of PNPLA3 with lipid droplet (LD)-associated proteins of the perilipin family, which serve as gatekeepers for LD degradation. In a collective of 106 NASH, ASH and control liver samples, immunohistochemical analyses revealed increased ballooning, inflammation and fibrosis, as well as an accumulation of PNPLA3-perilipin 5 complexes on larger LDs in patients homo- and heterozygous for PNPLA3(I148M). Co-immunoprecipitation demonstrated an interaction of PNPLA3 with perilipin 5 and the key enzyme of lipolysis, adipose triglyceride lipase (ATGL). Localization studies in cell cultures and human liver showed colocalization of perilipin 5, ATGL and PNPLA3. Moreover, the lipolytic activity of ATGL was negatively regulated by PNPLA3 and perilipin 5, whereas perilipin 1 displaced PNPLA3 from the ATGL complex. Furthermore, ballooned hepatocytes, the hallmark of steatohepatitis, were positive for PNPLA3 and perilipins 2 and 5, but showed decreased perilipin 1 expression with respect to neighboured hepatocytes. In summary, PNPLA3- and ATGL-driven lipolysis is significantly regulated by perilipin 1 and 5 in steatohepatitis.
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16
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den Braanker DJW, Maas RJH, van Mierlo G, Parr NMJ, Bakker-van Bebber M, Deegens JKJ, Jansen PWTC, Gloerich J, Willemsen B, Dijkman HB, van Gool AJ, Wetzels JFM, Rinschen MM, Vermeulen M, Nijenhuis T, van der Vlag J. Primary Focal Segmental Glomerulosclerosis Plasmas Increase Lipid Droplet Formation and Perilipin-2 Expression in Human Podocytes. Int J Mol Sci 2022; 24:ijms24010194. [PMID: 36613637 PMCID: PMC9820489 DOI: 10.3390/ijms24010194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/13/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Many patients with primary focal segmental glomerulosclerosis (FSGS) develop recurrence of proteinuria after kidney transplantation. Several circulating permeability factors (CPFs) responsible for recurrence have been suggested, but were never validated. We aimed to find proteins involved in the mechanism of action of CPF(s) and/or potential biomarkers for the presence of CPF(s). Cultured human podocytes were exposed to plasma from patients with FSGS with presumed CPF(s) or healthy and disease controls. Podocyte proteomes were analyzed by LC-MS. Results were validated using flow cytometry, RT-PCR, and immunofluorescence. Podocyte granularity was examined using flow cytometry, electron microscopy imaging, and BODIPY staining. Perilipin-2 protein expression was increased in podocytes exposed to presumed CPF-containing plasmas, and correlated with the capacity of plasma to induce podocyte granularity, identified as lipid droplet accumulation. Elevated podocyte perilipin-2 was confirmed at protein and mRNA level and was also detected in glomeruli of FSGS patients whose active disease plasmas induced podocyte perilipin-2 and lipid droplets. Our study demonstrates that presumably, CPF-containing plasmas from FSGS patients induce podocyte lipid droplet accumulation and perilipin-2 expression, identifying perilipin-2 as a potential biomarker. Future research should address the mechanism underlying CPF-induced alterations in podocyte lipid metabolism, which ultimately may result in novel leads for treatment.
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Affiliation(s)
- Dirk J. W. den Braanker
- Department of Nephrology, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Rutger J. H. Maas
- Department of Nephrology, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Guido van Mierlo
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands
- Oncode Institute, 3521 AL Utrecht, The Netherlands
| | - Naomi M. J. Parr
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Marinka Bakker-van Bebber
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Jeroen K. J. Deegens
- Department of Nephrology, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Pascal W. T. C. Jansen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands
- Oncode Institute, 3521 AL Utrecht, The Netherlands
| | - Jolein Gloerich
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Brigith Willemsen
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Henry B. Dijkman
- Department of Pathology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Alain J. van Gool
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Jack F. M. Wetzels
- Department of Nephrology, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Markus M. Rinschen
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
- Department of Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Michiel Vermeulen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, 6525 GA Nijmegen, The Netherlands
- Oncode Institute, 3521 AL Utrecht, The Netherlands
| | - Tom Nijenhuis
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Correspondence:
| | - Johan van der Vlag
- Department of Nephrology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
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17
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Mak KM, Wu C, Cheng CP. Lipid droplets, the Holy Grail of hepatic stellate cells: In health and hepatic fibrosis. Anat Rec (Hoboken) 2022; 306:983-1010. [PMID: 36516055 DOI: 10.1002/ar.25138] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 11/07/2022] [Accepted: 11/29/2022] [Indexed: 12/15/2022]
Abstract
Lipid droplets (LDs) are distinct morphological markers of hepatic stellate cells (HSCs). They are composed of a core of predominantly retinyl esters and triacylglycerols surrounded by a phospholipid layer; the latter harbors perilipins 2, 3, and 5, which help control LD lipolysis. Electron microscopy distinguishes between Types I and II LDs. Type I LDs are surrounded by acid phosphatase-positive lysosomes, which likely digest LDs. LD count and retinoid concentration are modulated by vitamin A intake. Alcohol consumption depletes hepatic retinoids and HSC LDs, with concomitant transformation of HSCs to fibrogenic myofibroblast-like cells. LD loss and accompanying HSC activation occur in HSC cell culture models. Loss of LDs is a consequence of and not a prerequisite for HSC activation. LDs are endowed with enzymes for synthesizing retinyl esters and triacylglycerols as well as neutral lipases and lysosomal acid lipase for breaking down LDs. HSCs have two distinct metabolic LD pools: an "original" pool in quiescent HSCs and a "new" pool emerging in HSC activation; this two-pool model provides a platform for analyzing LD dynamics in HSC activation. Besides lipolysis, LDs are degraded by lipophagy; however, the coordination between and relative contributions of these two pathways to LD removal are unclear. While induction of autophagy accelerates LD loss in quiescent HSCs and promotes HSC activation, blocking autophagy impairs LD degradation and inhibits HSC activation and fibrosis. This article is a critique of five decades of investigations into the morphology, molecular structure, synthesis, and degradation of LDs associated with HSC activation and fibrosis.
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Affiliation(s)
- Ki M Mak
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Catherine Wu
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Christopher P Cheng
- Department of Medical Education and Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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18
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Tang J, Zhao X, Wei W, Liu W, Fan H, Liu XP, Li Y, Wang L, Guo J. METTL16-mediated translation of CIDEA promotes non-alcoholic fatty liver disease progression via m6A-dependent manner. PeerJ 2022; 10:e14379. [PMID: 36518278 PMCID: PMC9744165 DOI: 10.7717/peerj.14379] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 10/20/2022] [Indexed: 12/05/2022] Open
Abstract
Background As the most prevalent chemical modifications on eukaryotic mRNAs, N6-methyladenosine (m6A) methylation was reported to participate in the regulation of various metabolic diseases. This study aimed to investigate the roles of m6A methylation and methyltransferase-like16 (METTL16) in non-alcoholic fatty liver disease (NAFLD). Methods In this study, we used a model of diet-induced NAFLD, maintaining six male C57BL/6J mice on high-fat diet (HFD) to generate hepatic steatosis. The high-throughput sequencing and RNA sequencing were performed to identify the m6A methylation patterns and differentially expressed mRNAs in HFD mice livers. Furthermore, we detected the expression levels of m6A modify enzymes by qRT-PCR in liver tissues, and further investigated the potential role of METTL16 in NAFLD through constructing overexpression and a knockdown model of METTL16 in HepG2 cells. Results In total, we confirmed 15,999 m6A recurrent peaks in HFD mice and 12,322 in the control. Genes with differentially methylated m6A peaks were significantly associated with the dysregulated glucolipid metabolism and aggravated hepatic inflammatory response. In addition, we identified five genes (CIDEA, THRSP, OSBPL3, GDF15 and LGALS1) that played important roles in NAFLD progression after analyzing the differentially expressed genes containing differentially methylated m6A peaks. Intriguingly, we found that the expression levels of METTL16 were substantially increased in the NAFLD model in vivo and in vitro, and further confirmed that METTL16 upregulated the expression level of lipogenic genes CIDEA in HepG2 cells. Conclusions These results indicate the critical roles of m6A methylation and METTL16 in HFD-induced mice and cell NAFLD models, which broaden people's perspectives on potential m6A-related treatments and biomarkers for NAFLD.
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Affiliation(s)
- Jinhong Tang
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China,Current Affiliation: Endoscopy Center, Minhang Hospital, Fudan University, Shanghai, P.R. China
| | - Xiangyun Zhao
- Digestive Endoscopic Center, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Wei Wei
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Weiwei Liu
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Huining Fan
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Xiu ping Liu
- Department of Gastroenterology, Shanghai Fudan University Affiliated Fifth People’s Hospital, Shanghai, China
| | - Yungai Li
- Department of Clinical Laboratory, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Long Wang
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Jinghui Guo
- Department of Gastroenterology, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
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19
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Schratter M, Lass A, Radner FPW. ABHD5-A Regulator of Lipid Metabolism Essential for Diverse Cellular Functions. Metabolites 2022; 12:1015. [PMID: 36355098 PMCID: PMC9694394 DOI: 10.3390/metabo12111015] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/19/2022] [Accepted: 10/23/2022] [Indexed: 11/12/2023] Open
Abstract
The α/β-Hydrolase domain-containing protein 5 (ABHD5; also known as comparative gene identification-58, or CGI-58) is the causative gene of the Chanarin-Dorfman syndrome (CDS), a disorder mainly characterized by systemic triacylglycerol accumulation and a severe defect in skin barrier function. The clinical phenotype of CDS patients and the characterization of global and tissue-specific ABHD5-deficient mouse strains have demonstrated that ABHD5 is a crucial regulator of lipid and energy homeostasis in various tissues. Although ABHD5 lacks intrinsic hydrolase activity, it functions as a co-activating enzyme of the patatin-like phospholipase domain-containing (PNPLA) protein family that is involved in triacylglycerol and glycerophospholipid, as well as sphingolipid and retinyl ester metabolism. Moreover, ABHD5 interacts with perilipins (PLINs) and fatty acid-binding proteins (FABPs), which are important regulators of lipid homeostasis in adipose and non-adipose tissues. This review focuses on the multifaceted role of ABHD5 in modulating the function of key enzymes in lipid metabolism.
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Affiliation(s)
- Margarita Schratter
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, 8010 Graz, Austria
| | - Achim Lass
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, 8010 Graz, Austria
- BioTechMed-Graz, 8010 Graz, Austria
- Field of Excellence BioHealth, 8010 Graz, Austria
| | - Franz P. W. Radner
- Institute of Molecular Biosciences, NAWI Graz, University of Graz, 8010 Graz, Austria
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20
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Metabolic Pathways as a Novel Landscape in Pancreatic Ductal Adenocarcinoma. Cancers (Basel) 2022; 14:cancers14153799. [PMID: 35954462 PMCID: PMC9367608 DOI: 10.3390/cancers14153799] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/01/2022] [Accepted: 08/03/2022] [Indexed: 11/17/2022] Open
Abstract
Metabolism plays a fundamental role in both human physiology and pathology, including pancreatic ductal adenocarcinoma (PDAC) and other tumors. Anabolic and catabolic processes do not only have energetic implications but are tightly associated with other cellular activities, such as DNA duplication, redox reactions, and cell homeostasis. PDAC displays a marked metabolic phenotype and the observed reduction in tumor growth induced by calorie restriction with in vivo models supports the crucial role of metabolism in this cancer type. The aggressiveness of PDAC might, therefore, be reduced by interventions on bioenergetic circuits. In this review, we describe the main metabolic mechanisms involved in PDAC growth and the biological features that may favor its onset and progression within an immunometabolic context. We also discuss the need to bridge the gap between basic research and clinical practice in order to offer alternative therapeutic approaches for PDAC patients in the more immediate future.
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21
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Yin R, Fu Y, Yousaf L, Xue Y, Hu J, Hu X, Shen Q. Crude and refined millet bran oil alleviate lipid metabolism disorders, oxidative stress and affect the gut microbiota composition in high‐fat diet‐induced mice. Int J Food Sci Technol 2022. [DOI: 10.1111/ijfs.15063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Ruiyang Yin
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Yongxia Fu
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Laraib Yousaf
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Yong Xue
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Jinrong Hu
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Xiaosong Hu
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
| | - Qun Shen
- Key Laboratory of Plant Protein and Grain processing National Engineering Research Center for Fruits and Vegetable Processing College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China
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22
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Preventive Effects of Ilex Cornuta Aqueous Extract on High-Fat Diet-Induced Fatty Liver of Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2022; 2022:7183471. [PMID: 35432557 PMCID: PMC9010189 DOI: 10.1155/2022/7183471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 03/09/2022] [Indexed: 12/26/2022]
Abstract
Objective To investigate the preventive effects of Ilex cornuta aqueous extract (ICAE) on high-fat diet (HFD)-induced fatty liver of mice and its mechanisms. Materials and Methods Twenty-six male KM (Kunming) mice were divided into 3 groups, including the control group (n = 9), fed with normal diet; HFD group (n = 9), fed with HFD; ICAE + HFD group (n = 8), fed with HFD and administered with ICAE (3 g·kg-1·d-1) at the same time for 10 weeks. Body weight, liver weight, intra-abdominal and subcutaneous fat weight, serum triglyceride (TG), total cholesterol (TC), and blood glucose were determined to evaluate the preventive effects of ICAE on obesity. The average 24 h food consumption of the mice was monitored for 5 times in the 9th week of the experiment to investigate the effects of ICAE on food intake. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) were assayed to observe the influences of HFD and ICAE on liver function. HE staining was adopted to observe the influence of ICAE on the morphology of adipose tissue and liver tissue. Hepatic TG and TC content assay and oil red O staining were used to evaluate the influences of ICAE on HFD-induced fatty liver, and the protein expression of peroxisome proliferator-activated receptors γ (PPARγ) and adipose differentiation-related protein (ADRP) in liver were examined by immunoblotting. Results ICAE treatment significantly reduced the increase of body weight, intra-abdominal, and subcutaneous fat and liver weight induced by HFD (P < 0.001), but has no influence on food intake; ICAE treatment attenuated the elevation of serum TG, TC, and glucose, as well as serum ALT and AST (P < 0.01, P < 0.05, P < 0.001) and dramatically decreased the content of TG in liver (P < 0.01), but has no influence on hepatic TC content. HE staining and oil red O staining showed that ICAE significantly reduced HFD-induced white adipocyte hypertrophy and significantly inhibited lipid accumulation in liver. Immunoblotting showed that the protein levels of PPARγ and ADRP were significantly increased by HFD induction, which can be dramatically reduced by ICAE treatment (P < 0.05, P < 0.0001). Conclusion ICAE has preventive effects on HFD-induced obesity and fatty liver in mice, exerted beneficial effects upon HFD-induced hepatic injury. The preventive effects of ICAE on fatty liver are concerned with the downregulation of PPARγ and ADRP protein expression in liver.
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23
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Wang Y, Zhao H, Yang L, Zhang H, Yu X, Fei W, Zhen Y, Gao Z, Chen S, Ren L. Quantitative proteomics analysis based on tandem mass tag labeling coupled with labeling coupled with liquid chromatography-tandem mass spectrometry discovers the effect of silibinin on non-alcoholic fatty liver disease in mice. Bioengineered 2022; 13:6750-6766. [PMID: 35246007 PMCID: PMC9208462 DOI: 10.1080/21655979.2022.2045837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In recent years, the beneficial effects of silibinin (SIL) on nonalcoholic fatty liver disease (NAFLD) have attracted widespread attention. We tried to study the intervention effect of SIL on NAFLD, and explore the potential mechanisms and targets of SIL on NAFLD improvement. Thirty-three male C57BL6/J mice were divided into three groups, and, respectively, fed a normal diet (ND), a high-fat diet (HFD) or a HFD given SIL treatment (HFD+SIL). Biochemical indexes and histopathological changes of mice in each group were detected. In addition, quantitative proteomics analysis based on tandem mass tag (TMT) labeling coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatics analysis was performed on protein changes in the livers. SIL could reduce the weight of mice, reduce liver lipid deposition, and improve glucose metabolism. Through comparison among the three experimental groups, a total of 30 overlapping proteins were found. These identified proteins were closely linked to liver lipid metabolism and energy homeostasis. Moreover, some drug targets were found, namely perilipin-2, phosphatidate phosphatase LPIN1, farnesyl pyrophosphate synthase, and glutathione S-transferase A1. In conclusions, high-fat diet increases the expressions of proteins implicated in lipid synthesis and transport in the liver, which can result in disorders of liver lipid metabolism. SIL can decrease liver lipid deposition and increase insulin sensitivity by regulating the expressions of these proteins. It not only improves the disorder of lipid metabolism in vivo, but also improves the disorder of glucose metabolism.
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Affiliation(s)
- Yichao Wang
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Hang Zhao
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Liying Yang
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - He Zhang
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Xian Yu
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Wenjie Fei
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Yunfeng Zhen
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Zhe Gao
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Shuchun Chen
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
| | - Luping Ren
- Department of Endocrinology, Hebei General Hospital, Shijiazhuang, Hebei, China
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24
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Abstract
Lipid droplets (LDs) are ubiquitous organelles that store and supply lipids for energy metabolism, membrane synthesis and production of lipid-derived signaling molecules. While compositional differences in the phospholipid monolayer or neutral lipid core of LDs impact their metabolism and function, the proteome of LDs has emerged as a major influencer in all aspects of LD biology. The perilipins (PLINs) are the most studied and abundant proteins residing on the LD surface. This Cell Science at a Glance and the accompanying poster summarize our current knowledge of the common and unique features of the mammalian PLIN family of proteins, the mechanisms through which they affect cell metabolism and signaling, and their links to disease.
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Affiliation(s)
- Charles P. Najt
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mahima Devarajan
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Douglas G. Mashek
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, University of Minnesota, Minneapolis, MN 55455, USA
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25
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Amelioration of hepatic steatosis by dietary essential amino acid-induced ubiquitination. Mol Cell 2022; 82:1528-1542.e10. [PMID: 35245436 DOI: 10.1016/j.molcel.2022.01.021] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 12/14/2021] [Accepted: 01/25/2022] [Indexed: 12/30/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a global health concern with no approved drugs. High-protein dietary intervention is currently the most effective treatment. However, its underlying mechanism is unknown. Here, using Drosophila oenocytes, the specialized hepatocyte-like cells, we find that dietary essential amino acids ameliorate hepatic steatosis by inducing polyubiquitination of Plin2, a lipid droplet-stabilizing protein. Leucine and isoleucine, two branched-chain essential amino acids, strongly bind to and activate the E3 ubiquitin ligase Ubr1, targeting Plin2 for degradation. We further show that the amino acid-induced Ubr1 activity is necessary to prevent steatosis in mouse livers and cultured human hepatocytes, providing molecular insight into the anti-NAFLD effects of dietary protein/amino acids. Importantly, split-intein-mediated trans-splicing expression of constitutively active UBR2, an Ubr1 family member, significantly ameliorates obesity-induced and high fat diet-induced hepatic steatosis in mice. Together, our results highlight activation of Ubr1 family proteins as a promising strategy in NAFLD treatment.
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26
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Chen Q, Fang W, Cui K, Chen Q, Xiang X, Zhang J, Zhang Y, Mai K, Ai Q. Endoplasmic reticulum stress induces hepatic steatosis by transcriptional upregulating lipid droplet protein perilipin2. FASEB J 2021; 35:e21900. [PMID: 34547130 DOI: 10.1096/fj.202100739rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 12/13/2022]
Abstract
Previous studies have shown that endoplasmic reticulum (ER) stress contributes to hepatic steatosis in several manners. However, how lipid droplet (LD) proteins participate in this process has rarely been reported. In the present study, ER stress was induced at both in vitro and in vivo levels with tunicamycin in large yellow croaker (Larimichthys crocea). Effects of LD protein perilipin2 (PLIN2) on hepatic lipid accumulation and lipoprotein transport under normal physiological condition and ER stress were then explored using dsRNA mediated knockdown. Subsequently, the transcriptional regulation of plin2 expression by transcription factors generated in the unfolded protein response (UPR) was determined by dual-luciferase reporter assays, chromatin immunoprecipitation and electrophoretic mobility-shift assay. We demonstrated that ER stress could promote LDs accumulation and inhibit lipoprotein transport by transcriptionally upregulating PLIN2 in liver. Among the transcription factors generated by UPR, spliced X-box binding protein1 can directly upregulated the expression of plin2, whereas C/EBP homologous protein can upregulate the expression of plin2 through peroxisome proliferator activated-receptor α. These results revealed that the LD protein PLIN2 played an important role in ER stress-induced hepatic steatosis, which might be a novel mechanism explaining hepatic steatosis triggered by ER stress.
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Affiliation(s)
- Qiuchi Chen
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Wei Fang
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Kun Cui
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Qiang Chen
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Xiaojun Xiang
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Junzhi Zhang
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Yunqiang Zhang
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China
| | - Kangsen Mai
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China.,Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, People's Republic of China
| | - Qinghui Ai
- Key laboratory of Aquaculture Nutrition and Feed, Ministry of Agriculture and Rural Affairs, and The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, People's Republic of China.,Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, People's Republic of China
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27
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Serum Perilipin 2 (PLIN2) Predicts Multiple Organ Dysfunction in Critically Ill Patients. Biomedicines 2021; 9:biomedicines9091210. [PMID: 34572396 PMCID: PMC8468514 DOI: 10.3390/biomedicines9091210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/03/2021] [Accepted: 09/07/2021] [Indexed: 12/24/2022] Open
Abstract
Perilipin 2 (PLIN2) is a lipid droplet protein with various metabolic functions. However, studies investigating PLIN2 in the context of inflammation, especially in systemic and acute inflammation, are lacking. Hence, we assessed the relevance of serum PLIN2 in critically ill patients. We measured serum PLIN2 serum in 259 critically ill patients (166 with sepsis) upon admission to a medical intensive care unit (ICU) compared to 12 healthy controls. A subset of 36 patients underwent computed tomography to quantify body composition. Compared to controls, serum PLIN2 concentrations were elevated in critically ill patients at ICU admission. Interestingly, PLIN2 independently indicated multiple organ dysfunction (MOD), defined as a SOFA score > 9 points, at ICU admission, and was also able to independently predict MOD after 48 h. Moreover, serum PLIN2 levels were associated with severe respiratory failure potentially reflecting a moribund state. However, PLIN2 was neither a predictor of ICU mortality nor did it reflect metabolic dysregulation. Conclusively, the first study assessing serum PLIN2 in critical illness proved that it may assist in risk stratification because it is capable of independently indicating MOD at admission and predicting MOD 48 h after PLIN2 measurement. Further evaluation regarding the underlying mechanisms is warranted.
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28
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Byun KA, Oh S, Son M, Oh SE, Park CH, Son KH, Byun K. Dieckol-Attenuated High-Fat Diet Induced Muscle Atrophy by Modulating Muscular Deposition of Lipid Droplets. Nutrients 2021; 13:3160. [PMID: 34579038 PMCID: PMC8467349 DOI: 10.3390/nu13093160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 08/31/2021] [Accepted: 09/08/2021] [Indexed: 11/17/2022] Open
Abstract
An excessive fat diet induces intramuscular fat deposition that accumulates as a form of lipid droplet (LD) and leads to lipotoxicity, including muscle atrophy or decreasing muscle strength. Lipotoxicity depends on the number of LDs, subcellular distribution (intermyofibrillar, IMF, LDs or subsarcolemmal, SS), and fiber type-specific differences (type I or type II fiber) as well as the size of LD. Ecklonia cava extracts (ECE), which is known to increase peroxisome proliferator-activated receptor alpha (PPAR-α), which leads to decreasing expression level of perilipin2 (PLIN2). PLIN2 is involved in modulating the size of LDs. This study shows that ECE and dieckol could decrease PLIN2 expression and decrease the size and number of LDs in the muscle of high-fat diet (HF)-fed animals and lead to attenuating muscle atrophy. Expression level of PPAR-α was decreased, and PLIN2 was increased by HF. ECE and dieckol increased PPAR-α expression and decreased PLIN2. The diameter of LDs was increased in high-fat diet condition, and it was decreased by ECE or dieckol treatment. The number of LDs in type II fibers/total LDs was increased by HF and it was decreased by ECE or dieckol. The SS LDs were increased, and IMF LDs were decreased by HF. ECE or dieckol decreased SS LDs and increased IMF LDs. The ECE or dieckol attenuated the upregulation of muscle atrophy-related genes including Murf1, Atrogin-1, and p53 by HF. ECE or dieckol increased the cross-sectional area of the muscle fibers and grip strength, which were decreased by HF. In conclusion, ECE or dieckol decreased the size of LDs and modulated the contribution of LDs to less toxic ones by decreasing PLIN2 expression and thus attenuated muscle atrophy and strength, which were induced by HF.
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Affiliation(s)
- Kyung-A Byun
- Department of Anatomy&Cell Biology, Gachon University College of Medicine, Incheon 21936, Korea; (K.-A.B.); (M.S.)
- Functional Cellular Networks Laboratory, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon University, Incheon 21999, Korea; (S.O.); (S.E.O.)
| | - Seyeon Oh
- Functional Cellular Networks Laboratory, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon University, Incheon 21999, Korea; (S.O.); (S.E.O.)
| | - Myeongjoo Son
- Department of Anatomy&Cell Biology, Gachon University College of Medicine, Incheon 21936, Korea; (K.-A.B.); (M.S.)
- Functional Cellular Networks Laboratory, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon University, Incheon 21999, Korea; (S.O.); (S.E.O.)
| | - Seung Eon Oh
- Functional Cellular Networks Laboratory, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon University, Incheon 21999, Korea; (S.O.); (S.E.O.)
| | - Chul-Hyun Park
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Korea;
| | - Kuk Hui Son
- Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Korea;
| | - Kyunghee Byun
- Department of Anatomy&Cell Biology, Gachon University College of Medicine, Incheon 21936, Korea; (K.-A.B.); (M.S.)
- Functional Cellular Networks Laboratory, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, College of Medicine, Gachon University, Incheon 21999, Korea; (S.O.); (S.E.O.)
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Guo L, Chao X, Huang W, Li Z, Luan K, Ye M, Zhang S, Liu M, Li H, Luo W, Nie Q, Zhang X, Luo Q. Whole Transcriptome Analysis Reveals a Potential Regulatory Mechanism of LncRNA-FNIP2/miR-24-3p/ FNIP2 Axis in Chicken Adipogenesis. Front Cell Dev Biol 2021; 9:653798. [PMID: 34249911 PMCID: PMC8265275 DOI: 10.3389/fcell.2021.653798] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 04/07/2021] [Indexed: 01/20/2023] Open
Abstract
Lipid biosynthesis is a complex process, which is regulated by multiple factors including lncRNA. However, the role of lncRNA in chicken abdominal fat accumulation is still unclear. In this research, we collected liver tissues from six high abdominal fat rate Sanhuang broilers and six low abdominal fat rate Sanhuang broilers to perform lncRNA sequencing and small RNA sequencing. A total of 2,265 lncRNAs, 245 miRNAs, and 5,315 mRNAs were differently expressed. Among of them, 1,136 differently expressed genes were enriched in the metabolic process. A total of 36 differently expressed genes, which were considered as differently expressed lncRNAs' targets, were enriched in the metabolic process. In addition, we also found out that eight differently expressed miRNAs could target 19 differently expressed genes. FNIP2 and PEX5L were shared in a cis-regulatory network and a differently expressed miRNA target relationship network. LncRNA-FNIP2/miR-24-3p/FNIP2 axis was considered as a potential candidate that may participate in lipid synthesis. Experimentally, the objective reality of lncRNA-FNIP2/miR-24-3p/FNIP2 axis was clarified and the regulation effect of lncRNA-FNIP2/miR-24-3p/FNIP2 axis on synthesis was validated. In brief, our study reveals a potential novel regulatory mechanism that lncRNA-FNIP2/miR-24-3p/FNIP2 axis was considered as being involved in lipid synthesis during chicken adipogenesis in liver.
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Affiliation(s)
- Lijin Guo
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Xiaohuan Chao
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Weiling Huang
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Zhenhui Li
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Kang Luan
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Mao Ye
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Siyu Zhang
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Manqing Liu
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Hongmei Li
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Wen Luo
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Qinghua Nie
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Xiquan Zhang
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Qingbin Luo
- Guangdong Laboratory, Lingnan Modern Agricultural Science and Technology, South China Agricultural University, Guangzhou, China
- College of Animal Science, South China Agricultural University, Guangzhou, China
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Zhang K, Chen X, Zhang P, Liu G. Perilipin2 is an Earlier Marker Than Perilipin1 for Identifying Adipocyte Regeneration in Fat Grafts. Aesthet Surg J 2021; 41:NP646-NP652. [PMID: 33319243 DOI: 10.1093/asj/sjaa360] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Both perilipin1 (Plin1) and perilipin2 (Plin2) play a crucial role in regulating lipid droplet (LD) formation in fat cells. Plin2 is expressed early in the adipocyte differentiation process but is replaced by Plin1 after cell maturation. In free fat grafts, only a small number of adipocytes remain alive or are replaced by newly regenerated fat cells. It is known that Plin1-positive adipocytes participate in regeneration, but the characteristics of Plin2 expression during this process are still poorly understood. OBJECTIVES The aim of this study was to investigate whether Plin2 is a more precise early marker for detecting adipocyte regeneration in fat grafts than Plin1. METHODS Autologous fat tissue (120 mg) harvested from inguinal fat pads was injected under the scalps of C57 mice. Samples were explanted at days 3, 7, 15, and 30 after transplantation. Changes in sample size and weight were evaluated. Hematoxylin-eosin staining, real-time polymerase chain reaction, and immunostaining of Plin1 and Plin2 expression were performed. RESULTS Plin1, but not Plin2, expression was detected in the freshly harvested fat, but the latter was activated after grafting. Newly regenerated Plin2-positive adipocytes increased from day 3 to day 7 and then declined, whereas the number of Plin1-positive fat cells decreased first and began to increase after day 15. The expression levels of Plin1 and Plin2 mRNA demonstrated similar changes over time. At day 30, adipocytes lost Plin2 expression and were positive for Plin1 again. CONCLUSIONS Our experiments showed convincing evidence that Plin2 expression could be used to detect early adipocyte regeneration in grafted fat tissue.
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Affiliation(s)
- Kaili Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Xi Chen
- Department of Plastic and Reconstructive Surgery, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, PR China
| | - Peng Zhang
- Department of Orthopaedics, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, PR China
| | - Guangpeng Liu
- Department of Plastic and Reconstructive Surgery, Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, PR China
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31
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Mishra A, Liu S, Promes J, Harata M, Sivitz W, Fink B, Bhardwaj G, O'Neill BT, Kang C, Sah R, Strack S, Stephens S, King T, Jackson L, Greenberg AS, Anokye-Danso F, Ahima RS, Ankrum J, Imai Y. Perilipin 2 downregulation in β cells impairs insulin secretion under nutritional stress and damages mitochondria. JCI Insight 2021; 6:144341. [PMID: 33784258 PMCID: PMC8262280 DOI: 10.1172/jci.insight.144341] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 03/24/2021] [Indexed: 12/15/2022] Open
Abstract
Perilipin 2 (PLIN2) is a lipid droplet (LD) protein in β cells that increases under nutritional stress. Downregulation of PLIN2 is often sufficient to reduce LD accumulation. To determine whether PLIN2 positively or negatively affects β cell function under nutritional stress, PLIN2 was downregulated in mouse β cells, INS1 cells, and human islet cells. β Cell–specific deletion of PLIN2 in mice on a high-fat diet reduced glucose-stimulated insulin secretion (GSIS) in vivo and in vitro. Downregulation of PLIN2 in INS1 cells blunted GSIS after 24-hour incubation with 0.2 mM palmitic acid. Downregulation of PLIN2 in human pseudoislets cultured at 5.6 mM glucose impaired both phases of GSIS, indicating that PLIN2 is critical for GSIS. Downregulation of PLIN2 decreased specific OXPHOS proteins in all 3 models and reduced oxygen consumption rates in INS1 cells and mouse islets. Moreover, we found that PLIN2-deficient INS1 cells increased the distribution of a fluorescent oleic acid analog to mitochondria and showed signs of mitochondrial stress, as indicated by susceptibility to fragmentation and alterations of acyl-carnitines and glucose metabolites. Collectively, PLIN2 in β cells has an important role in preserving insulin secretion, β cell metabolism, and mitochondrial function under nutritional stress.
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Affiliation(s)
- Akansha Mishra
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - Siming Liu
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - Joseph Promes
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - Mikako Harata
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - William Sivitz
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA.,Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
| | - Brian Fink
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA.,Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
| | - Gourav Bhardwaj
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - Brian T O'Neill
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA.,Iowa City Veterans Affairs Medical Center, Iowa City, Iowa, USA
| | - Chen Kang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Rajan Sah
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Stefan Strack
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa, USA
| | - Samuel Stephens
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
| | - Timothy King
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Laura Jackson
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, Virginia, USA
| | - Andrew S Greenberg
- Obesity and Metabolism Laboratory, Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts, USA
| | | | - Rexford S Ahima
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - James Ankrum
- Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA.,Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa, USA
| | - Yumi Imai
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.,Fraternal Order of Eagles Diabetes Research Center, University of Iowa, Iowa City, Iowa, USA
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32
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Griffin JD, Bejarano E, Wang XD, Greenberg AS. Integrated Action of Autophagy and Adipose Tissue Triglyceride Lipase Ameliorates Diet-Induced Hepatic Steatosis in Liver-Specific PLIN2 Knockout Mice. Cells 2021; 10:cells10051016. [PMID: 33923083 PMCID: PMC8145136 DOI: 10.3390/cells10051016] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 01/22/2023] Open
Abstract
An imbalance in the storage and breakdown of hepatic lipid droplet (LD) triglyceride (TAG) leads to hepatic steatosis, a defining feature of non-alcoholic fatty liver disease (NAFLD). The two primary cellular pathways regulating hepatic TAG catabolism are lipolysis, initiated by adipose triglyceride lipase (ATGL), and lipophagy. Each of these processes requires access to the LD surface to initiate LD TAG catabolism. Ablation of perilipin 2 (PLIN2), the most abundant lipid droplet-associated protein in steatotic liver, protects mice from diet-induced NAFLD. However, the mechanisms underlaying this protection are unclear. We tested the contributions of ATGL and lipophagy mediated lipolysis to reduced hepatic TAG in mice with liver-specific PLIN2 deficiency (PLIN2LKO) fed a Western-type diet for 12 weeks. We observed enhanced autophagy in the absence of PLIN2, as determined by ex vivo p62 flux, as well as increased p62- and LC3-positive autophagic vesicles in PLIN2LKO livers and isolated primary hepatocytes. Increased levels of autophagy correlated with significant increases in cellular fatty acid (FA) oxidation in PLIN2LKO hepatocytes. We observed that inhibition of either autophagy or ATGL blunted the increased FA oxidation in PLIN2LKO hepatocytes. Additionally, combined inhibition of ATGL and autophagy reduced FA oxidation to the same extent as treatment with either inhibitor alone. In sum, these studies show that protection against NAFLD in the absence of hepatic PLIN2 is driven by the integrated actions of both ATGL and lipophagy.
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Affiliation(s)
- John D. Griffin
- Obesity and Metabolism Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA;
| | - Eloy Bejarano
- Laboratory for Nutrition and Vision Research, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA;
- School of Health Sciences, Universidad CEU Cardenal Herrera, 46001 Valencia, Spain
| | - Xiang-Dong Wang
- Laboratory for Nutrition and Cancer Biology, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA;
| | - Andrew S. Greenberg
- Obesity and Metabolism Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA;
- Correspondence:
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Kalyesubula M, Mopuri R, Asiku J, Rosov A, Yosefi S, Edery N, Bocobza S, Moallem U, Dvir H. High-dose vitamin B1 therapy prevents the development of experimental fatty liver driven by overnutrition. Dis Model Mech 2021; 14:dmm.048355. [PMID: 33608323 PMCID: PMC7988776 DOI: 10.1242/dmm.048355] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/11/2021] [Indexed: 12/16/2022] Open
Abstract
Fatty liver is an abnormal metabolic condition of excess intrahepatic fat. This condition, referred to as hepatic steatosis, is tightly associated with chronic liver disease and systemic metabolic morbidity. The most prevalent form in humans, i.e. non-alcoholic fatty liver, generally develops due to overnutrition and sedentary lifestyle, and has as yet no approved drug therapy. Previously, we have developed a relevant large-animal model in which overnourished sheep raised on a high-calorie carbohydrate-rich diet develop hyperglycemia, hyperinsulinemia, insulin resistance, and hepatic steatosis. Here, we tested the hypothesis that treatment with thiamine (vitamin B1) can counter the development of hepatic steatosis driven by overnutrition. Remarkably, the thiamine-treated animals presented with completely normal levels of intrahepatic fat, despite consuming the same amount of liver-fattening diet. Thiamine treatment also decreased hyperglycemia and increased the glycogen content of the liver, but it did not improve insulin sensitivity, suggesting that steatosis can be addressed independently of targeting insulin resistance. Thiamine increased the catalytic capacity for hepatic oxidation of carbohydrates and fatty acids. However, at gene-expression levels, more-pronounced effects were observed on lipid-droplet formation and lipidation of very-low-density lipoprotein, suggesting that thiamine affects lipid metabolism not only through its known classic coenzyme roles. This discovery of the potent anti-steatotic effect of thiamine may prove clinically useful in managing fatty liver-related disorders.This article has an associated First Person interview with the joint first authors of the paper.
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Affiliation(s)
- Mugagga Kalyesubula
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel.,Department of Animal Science, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Ramgopal Mopuri
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel
| | - Jimmy Asiku
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel.,Institute of Biochemistry, Food Science and Nutrition, The Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - Alexander Rosov
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel
| | - Sara Yosefi
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel
| | - Nir Edery
- Pathology Laboratory, Kimron Veterinary Institute, Veterinary Services, Rishon LeZion 50250, Israel
| | - Samuel Bocobza
- Institute of Plant Sciences, Volcani Center - ARO, Rishon LeZion 7528809, Israel
| | - Uzi Moallem
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel
| | - Hay Dvir
- Institute of Animal Science, Volcani Center - Agricultural Research Organization (ARO), Rishon LeZion 7528809, Israel
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Hofer P, Taschler U, Schreiber R, Kotzbeck P, Schoiswohl G. The Lipolysome-A Highly Complex and Dynamic Protein Network Orchestrating Cytoplasmic Triacylglycerol Degradation. Metabolites 2020; 10:E147. [PMID: 32290093 PMCID: PMC7240967 DOI: 10.3390/metabo10040147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/03/2020] [Accepted: 04/08/2020] [Indexed: 12/25/2022] Open
Abstract
The catabolism of intracellular triacylglycerols (TAGs) involves the activity of cytoplasmic and lysosomal enzymes. Cytoplasmic TAG hydrolysis, commonly termed lipolysis, is catalyzed by the sequential action of three major hydrolases, namely adipose triglyceride lipase, hormone-sensitive lipase, and monoacylglycerol lipase. All three enzymes interact with numerous protein binding partners that modulate their activity, cellular localization, or stability. Deficiencies of these auxiliary proteins can lead to derangements in neutral lipid metabolism and energy homeostasis. In this review, we summarize the composition and the dynamics of the complex lipolytic machinery we like to call "lipolysome".
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Affiliation(s)
- Peter Hofer
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria; (P.H.); (U.T.); (R.S.)
| | - Ulrike Taschler
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria; (P.H.); (U.T.); (R.S.)
| | - Renate Schreiber
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria; (P.H.); (U.T.); (R.S.)
| | - Petra Kotzbeck
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria;
| | - Gabriele Schoiswohl
- Institute of Molecular Biosciences, University of Graz, 8010 Graz, Austria; (P.H.); (U.T.); (R.S.)
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35
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Western diet induces severe nonalcoholic steatohepatitis, ductular reaction, and hepatic fibrosis in liver CGI-58 knockout mice. Sci Rep 2020; 10:4701. [PMID: 32170127 PMCID: PMC7070035 DOI: 10.1038/s41598-020-61473-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 02/27/2020] [Indexed: 12/13/2022] Open
Abstract
Humans and rodents with Comparative Gene Identification-58 (CGI-58) mutations manifest nonalcoholic fatty liver disease (NAFLD). Here we show that liver CGI-58 knockout (LivKO) mice fed a Western diet rapidly develop advanced NAFLD, including nonalcoholic steatohepatitis (NASH) and hepatic fibrosis. After 14 weeks of diet challenge, starting at 6 weeks of age, LivKO mice showed increased inflammatory cell infiltration and proinflammatory gene expression in the liver, which was associated with elevated plasma levels of aminotransferases. Hepatic ductular reactions, pericellular fibrosis, and bridging fibrosis were observed only in the LivKO mice. Consistently, the KO mice had a significant increase in hepatic mRNAs for fibrogenic genes. In addition, LivKO mice displayed massive accumulation of lipid droplets (LDs) in hepatocytes. LDs were also observed in the cholangiocytes of the LivKO mice, but not the floxed controls. Four of the five LD coat proteins, including perilipins 2, 3, 4, and 5, were increased in the CGI-58 KO liver. CRISPR/Cas9-mediated knockout of CGI-58 in Huh7 human hepatoma cells induced LD deposition and perilipin expression, suggesting a cell autonomous effect. Our findings establish the Western diet-fed LivKO mice as an animal model of NASH and hepatic fibrosis. These animals may facilitate preclinical screening of therapeutic agents that counter against NAFLD progression.
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36
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Hatchwell L, Harney DJ, Cielesh M, Young K, Koay YC, O’Sullivan JF, Larance M. Multi-omics Analysis of the Intermittent Fasting Response in Mice Identifies an Unexpected Role for HNF4α. Cell Rep 2020; 30:3566-3582.e4. [DOI: 10.1016/j.celrep.2020.02.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/24/2020] [Accepted: 02/11/2020] [Indexed: 12/21/2022] Open
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37
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Irungbam K, Churin Y, Matono T, Weglage J, Ocker M, Glebe D, Hardt M, Koeppel A, Roderfeld M, Roeb E. Cannabinoid receptor 1 knockout alleviates hepatic steatosis by downregulating perilipin 2. J Transl Med 2020; 100:454-465. [PMID: 31570772 PMCID: PMC7044114 DOI: 10.1038/s41374-019-0327-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 08/30/2019] [Accepted: 09/08/2019] [Indexed: 02/07/2023] Open
Abstract
The endocannabinoid (EC) system has been implicated in the pathogenesis of several metabolic diseases, including nonalcoholic fatty liver disease (NAFLD). With the current study we aimed to verify the modulatory effect of endocannabinoid receptor 1 (CB1)-signaling on perilipin 2 (PLIN2)-mediated lipophagy. Here, we demonstrate that a global knockout of the cannabinoid receptor 1 gene (CB1-/-) reduced the expression of the lipid droplet binding protein PLIN2 in the livers of CB1-/- and hepatitis B surface protein (HBs)-transgenic mice, which spontaneously develop hepatic steatosis. In addition, the pharmacologic activation and antagonization of CB1 in cell culture also caused an induction or reduction of PLIN2, respectively. The decreased PLIN2 expression was associated with suppressed lipogenesis and triglyceride (TG) synthesis and enhanced autophagy as shown by increased colocalization of LC3B with lysosomal-associated membrane protein 1 (LAMP1) in HBs/CB1-/- mice. The induction of autophagy was further supported by the increased expression of LAMP1 in CB1-/- and HBs/CB1-/- mice. LAMP1 and PLIN2 were co-localized in HBs/CB1-/- indicating autophagy of cytoplasmic lipid droplets (LDs) i.e., lipophagy. Lipolysis of lipid droplets was additionally indicated by elevated expression of lysosomal acid lipase. In conclusion, these results suggest that loss of CB1 signaling leads to reduced PLIN2 abundance, which triggers lipophagy. Our new findings about the association between CB1 signaling and PLIN2 may stimulate translational studies analyzing new diagnostic and therapeutic options for NAFLD.
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Affiliation(s)
- Karuna Irungbam
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Yuri Churin
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Tomomitsu Matono
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Jakob Weglage
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Matthias Ocker
- Institute for Surgical Research, Philipps University of Marburg, Marburg, Germany
- Department of Gastroenterology CBF, Translational Medicine Oncology, Charité University Medicine Berlin and Bayer AG, Experimental Medicine Oncology, Berlin, Germany
| | - Dieter Glebe
- Institute of Medical Virology, National Reference Centre for Hepatitis B and D Viruses, Justus-Liebig-University, Giessen, Germany
| | - Martin Hardt
- Central Biotechnical Facility, Justus-Liebig-University, Giessen, Germany
| | - Alica Koeppel
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Martin Roderfeld
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany
| | - Elke Roeb
- Department of Gastroenterology, Justus-Liebig-University, Giessen, Germany.
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The Puzzling Conservation and Diversification of Lipid Droplets from Bacteria to Eukaryotes. Results Probl Cell Differ 2020; 69:281-334. [PMID: 33263877 DOI: 10.1007/978-3-030-51849-3_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Membrane compartments are amongst the most fascinating markers of cell evolution from prokaryotes to eukaryotes, some being conserved and the others having emerged via a series of primary and secondary endosymbiosis events. Membrane compartments comprise the system limiting cells (one or two membranes in bacteria, a unique plasma membrane in eukaryotes) and a variety of internal vesicular, subspherical, tubular, or reticulated organelles. In eukaryotes, the internal membranes comprise on the one hand the general endomembrane system, a dynamic network including organelles like the endoplasmic reticulum, the Golgi apparatus, the nuclear envelope, etc. and also the plasma membrane, which are linked via direct lateral connectivity (e.g. between the endoplasmic reticulum and the nuclear outer envelope membrane) or indirectly via vesicular trafficking. On the other hand, semi-autonomous organelles, i.e. mitochondria and chloroplasts, are disconnected from the endomembrane system and request vertical transmission following cell division. Membranes are organized as lipid bilayers in which proteins are embedded. The budding of some of these membranes, leading to the formation of the so-called lipid droplets (LDs) loaded with hydrophobic molecules, most notably triacylglycerol, is conserved in all clades. The evolution of eukaryotes is marked by the acquisition of mitochondria and simple plastids from Gram-positive bacteria by primary endosymbiosis events and the emergence of extremely complex plastids, collectively called secondary plastids, bounded by three to four membranes, following multiple and independent secondary endosymbiosis events. There is currently no consensus view of the evolution of LDs in the Tree of Life. Some features are conserved; others show a striking level of diversification. Here, we summarize the current knowledge on the architecture, dynamics, and multitude of functions of the lipid droplets in prokaryotes and in eukaryotes deriving from primary and secondary endosymbiosis events.
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39
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Yu L, Li Y, Grisé A, Wang H. CGI-58: Versatile Regulator of Intracellular Lipid Droplet Homeostasis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1276:197-222. [PMID: 32705602 PMCID: PMC8063591 DOI: 10.1007/978-981-15-6082-8_13] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Comparative gene identification-58 (CGI-58), also known as α/β-hydrolase domain-containing 5 (ABHD5), is a member of a large family of proteins containing an α/β-hydrolase-fold. CGI-58 is well-known as the co-activator of adipose triglyceride lipase (ATGL), which is a key enzyme initiating cytosolic lipid droplet lipolysis. Mutations in either the human CGI-58 or ATGL gene cause an autosomal recessive neutral lipid storage disease, characterized by the excessive accumulation of triglyceride (TAG)-rich lipid droplets in the cytoplasm of almost all cell types. CGI-58, however, has ATGL-independent functions. Distinct phenotypes associated with CGI-58 deficiency commonly include ichthyosis (scaly dry skin), nonalcoholic steatohepatitis, and hepatic fibrosis. Through regulated interactions with multiple protein families, CGI-58 controls many metabolic and signaling pathways, such as lipid and glucose metabolism, energy balance, insulin signaling, inflammatory responses, and thermogenesis. Recent studies have shown that CGI-58 regulates the pathogenesis of common metabolic diseases in a tissue-specific manner. Future studies are needed to molecularly define ATGL-independent functions of CGI-58, including the newly identified serine protease activity of CGI-58. Elucidation of these versatile functions of CGI-58 may uncover fundamental cellular processes governing lipid and energy homeostasis, which may help develop novel approaches that counter against obesity and its associated metabolic sequelae.
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Affiliation(s)
- Liqing Yu
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Yi Li
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Alison Grisé
- College of Computer, Math, and Natural Sciences, College of Behavioral and Social Sciences, University of Maryland, College Park, MD, USA
| | - Huan Wang
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
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Haaker MW, Kruitwagen HS, Vaandrager AB, Houweling M, Penning LC, Molenaar MR, van Wolferen ME, Oosterhoff LA, Spee B, Helms JB. Identification of potential drugs for treatment of hepatic lipidosis in cats using an in vitro feline liver organoid system. J Vet Intern Med 2019; 34:132-138. [PMID: 31830357 PMCID: PMC6979087 DOI: 10.1111/jvim.15670] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 11/12/2019] [Indexed: 01/18/2023] Open
Abstract
Background Hepatic lipidosis is increasing in incidence in the Western world, with cats being particularly sensitive. When cats stop eating and start utilizing their fat reserves, free fatty acids (FFAs) increase in blood, causing an accumulation of triacylglycerol (TAG) in the liver. Objective Identifying potential new drugs that can be used to treat hepatic lipidosis in cats using a feline hepatic organoid system. Animals Liver organoids obtained from 6 cats. Methods Eight different drugs were tested, and the 2 most promising were further studied using a quantitative TAG assay, lipid droplet staining, and qPCR. Results Both T863 (a diacylglycerol O‐acyltransferase 1 [DGAT1] inhibitor) and 5‐aminoimidazole‐4‐carboxamide 1‐β‐D‐ribofuranoside (AICAR; an adenosine monophosphate kinase activator) decreased TAG accumulation by 55% (P < .0001) and 46% (P = .0003), respectively. Gene expression of perilipin 2 (PLIN2) increased upon the addition of FFAs to the medium and decreased upon treatment with AICAR but not significantly after treatment with T863. Conclusions and Clinical Importance Two potential drugs useful in the treatment of hepatic lipidosis in cats were identified. The drug T863 inhibits DGAT1, indicating that DGAT1 is the primary enzyme responsible for TAG synthesis from external fatty acids in cat organoids. The drug AICAR may act as a lipid‐lowering compound via decreasing PLIN2 mRNA. Liver organoids can be used as an in vitro tool for drug testing in a species‐specific system and provide the basis for further clinical testing of drugs to treat steatosis.
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Affiliation(s)
- Maya W Haaker
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Hedwig S Kruitwagen
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Arie B Vaandrager
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Martin Houweling
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Louis C Penning
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Martijn R Molenaar
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Monique E van Wolferen
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Loes A Oosterhoff
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Bart Spee
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - J Bernd Helms
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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Hidalgo I, Nájera N, Meaney E, Pérez-Durán J, Valdespino-Vazquez Y, Villarreal F, Ceballos G. Effects of (-)-epicatechin on the time course of the expression of perilipins in a diet-induced model of nonalcoholic steatohepatitis. J Nutr Biochem 2019; 77:108296. [PMID: 32007822 DOI: 10.1016/j.jnutbio.2019.108296] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 10/30/2019] [Accepted: 11/07/2019] [Indexed: 12/25/2022]
Abstract
The existing treatments for nonalcoholic steatohepatitis (NASH) are not completely effective. The need for new alternatives without adverse effects and low cost, such as the flavonoid (-)-epicatechin (EC), which has beneficial effects on lipid metabolism and cardiovascular diseases, arises. The objective of this work was to analyze EC effects in the NASH induced by a Paigen-type diet (PD). Mice were administered with (1) normal chow and water, (2) PD + fructose 30% and (3) PD + fructose 30% + EC (1 mg/kg) per gavage during 9 weeks. At the end of each treatment, serum was collected for analysis of the biochemical profile and liver enzymes. The liver was collected for microscopic analysis and for the evaluation of the relative expression of Plin2, Plin3, CD36, adiponectin and UCP2. Results showed that EC reduced weight gain and decreased triglyceride (TG), low-density lipoprotein cholesterol, TG/high-density lipoprotein and the activity of liver enzymes (alanine aminotransferase and alkaline phosphatase), suggesting lower liver damage. The microscopic analysis showed less "balloonization" of the hepatocyte, small drops of lipids, less accumulation of collagen and infiltration of inflammatory cells as compared to nontreated group. Finally, a decrease in the expression of Plin 2 was observed. While CD36 decreased, adiponectin and UCP2 increased. In conclusion, EC improves the biochemical profile, the microscopic characteristics and protein expression. Therefore, it may be a possible therapeutic approach for NASH since it prevents the progression of the hepatic and metabolic damage induced by high-fat diets.
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Affiliation(s)
- Isabel Hidalgo
- Seccion de Posgrado, Escuela Superior de Medicina, Instituto Politecnico Nacional, Salvador Díaz Mirón esq. Plan de San Luis S/N, Miguel Hidalgo, Casco de Santo Tomas, 11340 Ciudad de Mexico, CDMX
| | - Nayelli Nájera
- Seccion de Posgrado, Escuela Superior de Medicina, Instituto Politecnico Nacional, Salvador Díaz Mirón esq. Plan de San Luis S/N, Miguel Hidalgo, Casco de Santo Tomas, 11340 Ciudad de Mexico, CDMX
| | - Eduardo Meaney
- Seccion de Posgrado, Escuela Superior de Medicina, Instituto Politecnico Nacional, Salvador Díaz Mirón esq. Plan de San Luis S/N, Miguel Hidalgo, Casco de Santo Tomas, 11340 Ciudad de Mexico, CDMX
| | - Javier Pérez-Durán
- Laboratorio de Genetica y Genomica humana, Instituto Nacional de Perinatologia, Montes Urales 800, Lomas Virreyes, Lomas de Chapultepec, 11000 Ciudad de Mexico, CDMX
| | - Yolotzin Valdespino-Vazquez
- Anatomia Patologica. Instituto Nacional de Perinatologia, Montes Urales 800, Lomas Virreyes, Lomas de Chapultepec, 11000 Ciudad de Mexico, CDMX
| | - Francisco Villarreal
- Department of Medicine, School of Medicine, University of California, San Diego, La Jolla, CA
| | - Guillermo Ceballos
- Seccion de Posgrado, Escuela Superior de Medicina, Instituto Politecnico Nacional, Salvador Díaz Mirón esq. Plan de San Luis S/N, Miguel Hidalgo, Casco de Santo Tomas, 11340 Ciudad de Mexico, CDMX.
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New insight into the mechanisms of ectopic fat deposition improvement after bariatric surgery. Sci Rep 2019; 9:17315. [PMID: 31754142 PMCID: PMC6872729 DOI: 10.1038/s41598-019-53702-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 09/18/2019] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic fatty-liver disease (NAFLD) is frequent in obese patients and represents a major risk factor for the development of diabetes and its complications. Bariatric surgery reverses the hepatic features of NAFLD. However, its mechanism of action remains elusive. We performed a comprehensive analysis of the mechanism leading to the improvement of NAFLD and insulin resistance in both obese rodents and humans following sleeve-gastrectomy (SG). SG improved insulin sensitivity and reduced hepatic and monocyte fat accumulation. Importantly, fat accumulation in monocytes was well comparable to that in hepatocytes, suggesting that Plin2 levels in monocytes might be a non-invasive marker for the diagnosis of NAFLD. Both in vitro and in vivo studies demonstrated an effective metabolic regeneration of liver function and insulin sensitivity. Specifically, SG improved NAFLD significantly by enhancing AMP-activated protein kinase (AMPK) phosphorylation and chaperone-mediated autophagy (CMA) that translate into the removal of Plin2 coating lipid droplets. This led to an increase in lipolysis and specific amelioration of hepatic insulin resistance. Elucidating the mechanism of impaired liver metabolism in obese subjects will help to design new strategies for the prevention and treatment of NAFLD.
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43
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Sané A, Ahmarani L, Delvin E, Auclair N, Spahis S, Levy E. SAR1B GTPase is necessary to protect intestinal cells from disorders of lipid homeostasis, oxidative stress, and inflammation. J Lipid Res 2019; 60:1755-1764. [PMID: 31409740 PMCID: PMC6795079 DOI: 10.1194/jlr.ra119000119] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/29/2019] [Indexed: 12/12/2022] Open
Abstract
Genetic defects in SAR1B GTPase inhibit chylomicron (CM) trafficking to the Golgi and result in a huge intraenterocyte lipid accumulation with a failure to release CMs and liposoluble vitamins into the blood circulation. The central aim of this study is to test the hypothesis that SAR1B deletion (SAR1B−/−) disturbs enterocyte lipid homeostasis (e.g., FA β-oxidation and lipogenesis) while promoting oxidative stress and inflammation. Another issue is to compare the impact of SAR1B−/− to that of its paralogue SAR1A−/− and combined SAR1A−/−/B−/−. To address these critical issues, we have generated Caco-2/15 cells with a knockout of SAR1A, SAR1B, or SAR1A/B genes. SAR1B−/− results in lipid homeostasis disruption, reflected by enhanced mitochondrial FA β-oxidation and diminished lipogenesis in intestinal absorptive cells via the implication of PPARα and PGC1α transcription factors. Additionally, SAR1B−/−cells, which mimicked enterocytes of CM retention disease, spontaneously disclosed inflammatory and oxidative characteristics via the implication of NF-κB and NRF2. In most conditions, SAR1A−/− cells showed a similar trend, albeit less dramatic, but synergetic effects were observed with the combined defects of the two SAR1 paralogues. In conclusion, SAR1B and its paralogue are needed not only for CM trafficking but also for lipid homeostasis, prooxidant/antioxidant balance, and protection against inflammatory processes.
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Affiliation(s)
- Alain Sané
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Lena Ahmarani
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Edgard Delvin
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Nikolas Auclair
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.,Departments of Pharmacology, Université de Montréal, Montreal, Quebec, Canada
| | - Schohraya Spahis
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada.,Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Emile Levy
- Research Centre, CHU-Sainte-Justine, Université de Montréal, Montreal, Quebec, Canada .,Departments of Pharmacology, Université de Montréal, Montreal, Quebec, Canada.,Nutrition, Université de Montréal, Montreal, Quebec, Canada
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44
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45
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Cansby E, Kulkarni NM, Magnusson E, Kurhe Y, Amrutkar M, Nerstedt A, Ståhlman M, Sihlbom C, Marschall HU, Borén J, Blüher M, Mahlapuu M. Protein kinase MST3 modulates lipid homeostasis in hepatocytes and correlates with nonalcoholic steatohepatitis in humans. FASEB J 2019; 33:9974-9989. [PMID: 31173506 DOI: 10.1096/fj.201900356rr] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ectopic lipid storage in the liver is considered the main risk factor for nonalcoholic steatohepatitis (NASH). Understanding the molecular networks controlling hepatocellular lipid deposition is therefore essential for developing new strategies to effectively prevent and treat this complex disease. Here, we describe a new regulator of lipid partitioning in human hepatocytes: mammalian sterile 20-like (MST) 3. We found that MST3 protein coats lipid droplets in mouse and human liver cells. Knockdown of MST3 attenuated lipid accumulation in human hepatocytes by stimulating β-oxidation and triacylglycerol secretion while inhibiting fatty acid influx and lipid synthesis. We also observed that lipogenic gene expression and acetyl-coenzyme A carboxylase protein abundance were reduced in MST3-deficient hepatocytes, providing insight into the molecular mechanisms underlying the decreased lipid storage. Furthermore, MST3 expression was positively correlated with key features of NASH (i.e., hepatic lipid content, lobular inflammation, and hepatocellular ballooning) in human liver biopsies. In summary, our results reveal a role of MST3 in controlling the dynamic metabolic balance of liver lipid catabolism vs. lipid anabolism. Our findings highlight MST3 as a potential drug target for the prevention and treatment of NASH and related complex metabolic diseases.-Cansby, E., Kulkarni, N. M., Magnusson, E., Kurhe, Y., Amrutkar, M., Nerstedt, A., Ståhlman, M., Sihlbom, C., Marschall, H.-U., Borén, J., Blüher, M., Mahlapuu, M. Protein kinase MST3 modulates lipid homeostasis in hepatocytes and correlates with nonalcoholic steatohepatitis in humans.
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Affiliation(s)
- Emmelie Cansby
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Nagaraj M Kulkarni
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Elin Magnusson
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Yeshwant Kurhe
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Manoj Amrutkar
- Department of Hepato-Pancreato-Biliary Surgery, Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Annika Nerstedt
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Carina Sihlbom
- Proteomics Core Facility, University of Gothenburg, Gothenburg, Sweden
| | - Hanns-Ulrich Marschall
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Jan Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Matthias Blüher
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Margit Mahlapuu
- Department of Chemistry and Molecular Biology, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
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46
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Tang P, Low HB, Png CW, Torta F, Kumar JK, Lim HY, Zhou Y, Yang H, Angeli V, Shabbir A, Tai ES, Flavell RA, Dong C, Wenk MR, Yang DY, Zhang Y. Protective Function of Mitogen-Activated Protein Kinase Phosphatase 5 in Aging- and Diet-Induced Hepatic Steatosis and Steatohepatitis. Hepatol Commun 2019; 3:748-762. [PMID: 31168510 PMCID: PMC6546013 DOI: 10.1002/hep4.1324] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/19/2019] [Indexed: 01/09/2023] Open
Abstract
Nonalcoholic fatty liver disease is currently the most common liver disease and is a leading cause of liver-related morbidity and mortality. However, its pathogenesis remains largely unclear. We previously showed that mice deficient in mitogen-activated protein kinase (MAPK) phosphatase 5 (MKP5) spontaneously developed insulin resistance and glucose intolerance, which are associated with visceral obesity and adipose tissue inflammation. In this study, we discovered that mice deficient in MKP5 developed more severe hepatic steatosis and steatohepatitis with age or with feeding on a high-fat diet (HFD) compared to wild-type (WT) mice, and this was associated with increased expression of proinflammatory cytokines and collagen genes. Increased p38 activation in MKP5 knockout (KO) liver compared to that in WT liver was detected, which contributed to increased expression of lipid droplet-associated protein cell death-inducing DFF45-like effector A (CIDEA) and CIDEC/fat-specific protein 27 but not CIDEB through activating transcription factor 2 (ATF2). In addition, MKP5 KO liver had higher peroxisome proliferator-activated receptor gamma (PPARγ) expression compared with WT liver. On the other hand, overexpression of MKP5 or inhibition of p38 activation in hepatocytes resulted in reduced expression of PPARγ. Inhibition of p38 resulted in alleviation of hepatic steatosis in KO liver in response to HFD feeding, and this was associated with reduced expression of CIDEA, CIDEC, and proinflammatory cytokines. Conclusion: MKP5 prevents the development of nonalcoholic steatohepatitis by suppressing p38-ATF2 and p38-PPARγ to reduce hepatic lipid accumulation, inflammation, and fibrosis.
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Affiliation(s)
- Peng Tang
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
| | - Heng Boon Low
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
| | - Chin Wen Png
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
| | - Federico Torta
- Department of BiochemistryYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Singapore Lipidomics Incubator, Life Sciences InstituteNational University of SingaporeSingapore
| | - Jaspal Kaur Kumar
- Singapore Lipidomics Incubator, Life Sciences InstituteNational University of SingaporeSingapore
| | - Hwee Ying Lim
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
| | - Yi Zhou
- Cancer Science Institute of SingaporeYong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - Henry Yang
- Cancer Science Institute of SingaporeYong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - Veronique Angeli
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
| | - Asim Shabbir
- Department of MedicineYong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - E. Shyong Tai
- Department of MedicineYong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - Richard A. Flavell
- Department of ImmunobiologyHoward Hughes Medical Institute, Yale UniversityNew HavenCT
| | | | - Markus R. Wenk
- Department of BiochemistryYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Singapore Lipidomics Incubator, Life Sciences InstituteNational University of SingaporeSingapore
| | - Dan Yock Yang
- Department of MedicineYong Loo Lin School of Medicine, National University of SingaporeSingapore
| | - Yongliang Zhang
- Department of Microbiology and ImmunologyYong Loo Lin School of Medicine, National University of SingaporeSingapore
- Immunology Program, Life Sciences InstituteNational University of SingaporeSingapore
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47
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Mardani I, Tomas Dalen K, Drevinge C, Miljanovic A, Ståhlman M, Klevstig M, Scharin Täng M, Fogelstrand P, Levin M, Ekstrand M, Nair S, Redfors B, Omerovic E, Andersson L, Kimmel AR, Borén J, Levin MC. Plin2-deficiency reduces lipophagy and results in increased lipid accumulation in the heart. Sci Rep 2019; 9:6909. [PMID: 31061399 PMCID: PMC6502866 DOI: 10.1038/s41598-019-43335-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 04/23/2019] [Indexed: 12/18/2022] Open
Abstract
Myocardial dysfunction is commonly associated with accumulation of cardiac lipid droplets (LDs). Perilipin 2 (Plin2) is a LD protein that is involved in LD formation, stability and trafficking events within the cell. Even though Plin2 is highly expressed in the heart, little is known about its role in myocardial lipid storage. A recent report shows that cardiac overexpression of Plin2 result in massive myocardial steatosis suggesting that Plin2 stabilizes LDs. In this study, we hypothesized that deficiency in Plin2 would result in reduced myocardial lipid storage. In contrast to our hypothesis, we found increased accumulation of triglycerides in hearts, and specifically in cardiomyocytes, from Plin2−/− mice. Although Plin2−/− mice had markedly enhanced lipid levels in the heart, they had normal heart function under baseline conditions and under mild stress. However, after an induced myocardial infarction, stroke volume and cardiac output were reduced in Plin2−/− mice compared with Plin2+/+ mice. We further demonstrated that the increased triglyceride accumulation in Plin2-deficient hearts was caused by altered lipophagy. Together, our data show that Plin2 is important for proper hydrolysis of LDs.
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Affiliation(s)
- Ismena Mardani
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Knut Tomas Dalen
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Christina Drevinge
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Azra Miljanovic
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Martina Klevstig
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Margareta Scharin Täng
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Per Fogelstrand
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Max Levin
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Matias Ekstrand
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Syam Nair
- Centre of Perinatal Medicine and Health, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Björn Redfors
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Elmir Omerovic
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Linda Andersson
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Alan R Kimmel
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Jan Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Malin C Levin
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, the Sahlgrenska Academy at University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden.
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48
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Redwan EM, Alkarim SA, El-Hanafy AA, Saad YM, Almehdar HA, Uversky VN. Disorder in milk proteins: adipophilin and TIP47, important constituents of the milk fat globule membrane. J Biomol Struct Dyn 2019; 38:1214-1229. [PMID: 30896308 DOI: 10.1080/07391102.2019.1592027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Milk fat globules (MFGs), which are secreted by the epithelial cells of the lactating mammary glands, account for the most of the nutritional value of milk. They are enveloped by the milk fat globule membrane (MFGM), a complex structure consisting of three phospholipid membrane monolayers and containing various lipids. Depending on the origin of milk, specific proteins accounts for 5-70% of the MFGM mass. Proteome of MFGMs includes hundreds of proteins, with nine major components being adipophilin, butyrophilin, cluster of differentiation 36, fatty acid binding protein, lactadherin, mucin 1, mucin 15, tail-interacting protein 47 (TIP47), and xanthine oxidoreductase. Two of the MFGM components, adipophilin and TIP47, belong to the five-member perilipin family of lipid droplet proteins. Adipophilin is involved in the formation of cytoplasmic lipid droplets and secretion of MFGs. This protein is also related to the formation of other lipid droplets that exist in most cell types, playing an important role in the transport of lipids from ER to the surface of lipid droplets. TIP47 acts as a cytoplasmic sorting factor for mannose 6-phosphate receptors and is recruited to the MFGM. Therefore, both adipophilin and TIP47 are moonlighting proteins, each possessing several unrelated functions. This review focuses on the main functions and specific structural features of adipophilin and TIP47, analyzes similarities and differences of these proteins among different species, and describes these proteins in the context of other members of the perilipin family.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Elrashdy M Redwan
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Protein Research Department, Therapeutic and Protective Proteins Laboratory, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research and Technology Applications, Alexandria, Egypt
| | - Saleh A Alkarim
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Amr A El-Hanafy
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Nucleic Acid Research, Genetic Engineering and Biotechnology Research Institute, City for Scientific Research & Technology Applications, Borg EL-Arab, Alexandria, Egypt
| | - Yasser M Saad
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Genetics Laboratory, National Institute of Oceanography and Fisheries, Cairo, Egypt
| | - Hussein A Almehdar
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Vladimir N Uversky
- Biological Sciences Department, Faculty of Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Russia Moscow Region.,Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
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49
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Varghese M, Kimler VA, Ghazi FR, Rathore GK, Perkins GA, Ellisman MH, Granneman JG. Adipocyte lipolysis affects Perilipin 5 and cristae organization at the cardiac lipid droplet-mitochondrial interface. Sci Rep 2019; 9:4734. [PMID: 30894648 PMCID: PMC6426865 DOI: 10.1038/s41598-019-41329-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 03/04/2019] [Indexed: 12/14/2022] Open
Abstract
This study investigated the effects of elevated fatty acid (FA) supply from adipose tissue on the ultrastructure of cardiac lipid droplets (LDs) and the expression and organization of LD scaffold proteins perilipin-2 (PLIN2) and perilipin-5 (PLIN5). Stimulation of adipocyte lipolysis by fasting (24 h) or β3-adrenergic receptor activation by CL316, 243 (CL) increased cardiac triacylglycerol (TAG) levels and LD size, whereas CL treatment also increased LD number. LDs were tightly associated with mitochondria, which was maintained during LD expansion. Electron tomography (ET) studies revealed continuity of LD and smooth endoplasmic reticulum (SER), suggesting interconnections among LDs. Under fed ad libitum conditions, the cristae of mitochondria that apposed LD were mostly organized perpendicularly to the tangent of the LD surface. Fasting significantly reduced, whereas CL treatment greatly increased, the perpendicular alignment of mitochondrial cristae. Fasting and CL treatment strongly upregulated PLIN5 protein and PLIN2 to a lesser extent. Immunofluorescence and immuno-electron microscopy demonstrated strong targeting of PLIN5 to the cardiac LD-mitochondrial interface, but not to the mitochondrial matrix. CL treatment augmented PLIN5 targeting to the LD-mitochondrial interface, whereas PLIN2 was not significantly affected. Together, our results support the concept that the interface between LD and cardiac mitochondria represents an organized and dynamic "metabolic synapse" that is highly responsive to FA trafficking.
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Affiliation(s)
- Mita Varghese
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Victoria A Kimler
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Fariha R Ghazi
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Gurnoor K Rathore
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Guy A Perkins
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA, 92093, USA
| | - James G Granneman
- Center for Integrative Metabolic and Endocrine Research, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
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50
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Orlicky DJ, Libby AE, Bales ES, McMahan RH, Monks J, La Rosa FG, McManaman JL. Perilipin-2 promotes obesity and progressive fatty liver disease in mice through mechanistically distinct hepatocyte and extra-hepatocyte actions. J Physiol 2019; 597:1565-1584. [PMID: 30536914 PMCID: PMC6418763 DOI: 10.1113/jp277140] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 12/05/2018] [Indexed: 12/22/2022] Open
Abstract
KEY POINTS Wild-type mice and mice with hepatocyte-specific or whole-body deletions of perilipin-2 (Plin2) were used to define hepatocyte and extra-hepatocyte effects of altered cellular lipid storage on obesity and non-alcoholic fatty liver disease (NAFLD) pathophysiology in a Western-diet (WD) model of these disorders. Extra-hepatocyte actions of Plin2 are responsible for obesity, adipose inflammation and glucose clearance abnormalities in WD-fed mice. Hepatocyte and extra-hepatic actions of Plin2 mediate fatty liver formation in WD-fed mice through distinct mechanisms. Hepatocyte-specific actions of Plin2 are primary mediators of immune cell infiltration and fibrotic injury in livers of obese mice. ABSTRACT Non-alcoholic fatty liver disease (NAFLD) is an obesity- and insulin resistance-related metabolic disorder with progressive pathology. Perilipin-2 (Plin2), a ubiquitously expressed cytoplasmic lipid droplet scaffolding protein, is hypothesized to contribute to NAFLD in humans and rodent models through effects on cellular lipid metabolism. In this study, we delineate hepatocyte-specific and extra-hepatocyte Plin2 mechanisms regulating the effects of obesity and insulin resistance on NAFLD pathophysiology in mice fed an obesogenic Western-style diet (WD). Total Plin2 deletion (Plin2-Null) fully protected WD-fed mice from obesity, insulin resistance, adipose inflammation, steatohepatitis (NASH) and liver fibrosis found in WT animals. Hepatocyte-specific Plin2 deletion (Plin2-HepKO) largely protected against NASH and fibrosis and partially protected against steatosis in WD-fed animals, but it did not protect against obesity, insulin resistance, or adipose inflammation. Significantly, total or hepatocyte-specific Plin2 deletion impaired WD-induced monocyte recruitment and pro-inflammatory macrophage polarization found in livers of WT mice. Analyses of the molecular and cellular processes mediating steatosis, inflammation and fibrosis identified differences in total and hepatocyte-specific actions of Plin2 on the mechanisms promoting NAFLD pathophysiology. Our results demonstrate that hepatocyte-specific actions of Plin2 are central to the initiation and pathological progression of NAFLD in obese and insulin-resistant mice through effects on immune cell recruitment and fibrogenesis. Conversely, extra-hepatocyte Plin2 actions promote NAFLD pathophysiology through effects on obesity, inflammation and insulin resistance. Our findings provide new insight into hepatocyte and extra-hepatocyte mechanisms underlying NAFLD development and progression.
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Affiliation(s)
- David J. Orlicky
- Department of PathologyUniversity of Colorado School of MedicineAuroraCOUSA
| | - Andrew E. Libby
- Graduate Program in Integrated PhysiologyUniversity of Colorado School of MedicineAuroraCOUSA
- Division of Reproductive SciencesUniversity of Colorado School of MedicineAuroraCOUSA
| | - Elise S. Bales
- Division of Reproductive SciencesUniversity of Colorado School of MedicineAuroraCOUSA
| | - Rachel H. McMahan
- Division of Gastroenterology and HepatologyUniversity of Colorado School of MedicineAuroraCOUSA
| | - Jenifer Monks
- Division of Reproductive SciencesUniversity of Colorado School of MedicineAuroraCOUSA
| | | | - James L. McManaman
- Graduate Program in Integrated PhysiologyUniversity of Colorado School of MedicineAuroraCOUSA
- Division of Reproductive SciencesUniversity of Colorado School of MedicineAuroraCOUSA
- Center for Human NutritionUniversity of Colorado School of MedicineAuroraCOUSA
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