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Ding M, Li QF, Peng TH, Wang TQ, Yan HH, Tang C, Wang XY, Guo Y, Zheng L. Early life exercise training and inhibition of apoLpp mRNA expression to improve age-related arrhythmias and prolong the average lifespan in Drosophila melanogaster. Aging (Albany NY) 2022; 14:9908-9923. [PMID: 36470666 PMCID: PMC9831727 DOI: 10.18632/aging.204422] [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: 04/05/2022] [Accepted: 11/16/2022] [Indexed: 01/03/2023]
Abstract
Cardiovascular disease (CVD) places a heavy burden on older patients and the global healthcare system. A large body of evidence suggests that exercise training is essential in preventing and treating cardiovascular disease, but the underlying mechanisms are not well understood. Here, we used the Drosophila melanogaster animal model to study the effects of early-life exercise training (Exercise) on the aging heart and lifespan. We found in flies that age-induced arrhythmias are conserved across different genetic backgrounds. The fat body is the primary source of circulating lipoproteins in flies. Inhibition of fat body apoLpp (Drosophila apoB homolog) demonstrated that low expression of apoLpp reduced the development of arrhythmias in aged flies but did not affect average lifespan. At the same time, exercise can also reduce the expression of apoLpp mRNA in aged flies and have a protective effect on the heart, which is similar to the inhibition of apoLpp mRNA. Although treatment of UAS-apoLppRNAi and exercise alone had no significant effect on lifespan, the combination of UAS-apoLppRNAi and exercise extended the average lifespan of flies. Therefore, we conclude that UAS-apoLppRNAi and exercise are sufficient to resist age-induced arrhythmias, which may be related to the decreased expression of apoLpp mRNA, and that UAS-apoLppRNAi and exercise have a combined effect on prolonging the average lifespan.
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Affiliation(s)
- Meng Ding
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Qiu Fang Li
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Tian Hang Peng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Tong Quan Wang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Han Hui Yan
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Chao Tang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Xiao Ya Wang
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Yin Guo
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
| | - Lan Zheng
- Key Laboratory of Physical Fitness and Exercise Rehabilitation of Hunan Province, Hunan Normal University, Changsha, China
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Ding M, Zhang S, Guo Y, Yao J, Shen Q, Huang M, Chen W, Yu S, Zheng Y, Lin Y, Yan W, Liu Z, Su T, Lu L. Tumor Microenvironment Acidity Triggers Lipid Accumulation in Liver Cancer via SCD1 Activation. Mol Cancer Res 2022; 20:810-822. [PMID: 35046108 DOI: 10.1158/1541-7786.mcr-21-0699] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/30/2021] [Accepted: 01/10/2022] [Indexed: 01/18/2023]
Abstract
Acidification is recognized as the predominant characteristic of the tumor microenvironment (TME) and contributes to tumor progression. However, the mechanism of extracellular acidic TME directly influences intercellular pathological responses remains unclear. Meanwhile, acidic TME is mainly ascribed to aberrant metabolism of lipids and glucose, but whether and how acidity affects metabolic reprogramming, especially for lipid metabolism, is still unknown. We found that lipid was significantly accumulated in liver cancer cells when exposed to acidic TME. Moreover, proteomic analysis showed that differentially expressed proteins were mainly clustered into fatty acid pathways. Subsequently, we found that acidification increased the expression of SCD1 by activating PI3K/AKT signaling pathway. Interestingly, we found that SCD1 directly bound to PPARα in the acidic TME, which vanished after 2-day reverse incubation in pH7.4 medium, implying extracellular acidosis might influence intercellular function by mediating the binding affinity between SCD1 and PPARα under different pH gradients. In summary, our data revealed that acidosis could significantly trigger fatty acid synthesis to promote liver tumorigenesis by upregulating SCD1 in a PI3K/AKT activation dependent manner and simultaneously promote SCD1 binding to PPARα. Our study not only provides direct mechanistic evidence to support the vital role of acidosis in lipid metabolic reprogramming, but also provides novel insights for determining the binding affinity of functional proteins as a molecular mechanism to better understand the role of the acidic TME in tumor development. Implications: The acidic TME contributes to lipid accumulation in liver cancer by activating the PI3K/AKT signaling pathway and promoting SCD1-PPARα binding.
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Affiliation(s)
- Ming Ding
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Shuwei Zhang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Yajuan Guo
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | | | - Qinghong Shen
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Min Huang
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Wenbo Chen
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Shaofang Yu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Yaqiu Zheng
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Yuefang Lin
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Wenxin Yan
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Zhongqiu Liu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
| | - Tao Su
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine
| | - Linlin Lu
- International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine
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Bhattarai KR, Kim HK, Chaudhary M, Ur Rashid MM, Kim J, Kim HR, Chae HJ. TMBIM6 regulates redox-associated posttranslational modifications of IRE1α and ER stress response failure in aging mice and humans. Redox Biol 2021; 47:102128. [PMID: 34562874 PMCID: PMC8476450 DOI: 10.1016/j.redox.2021.102128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 08/30/2021] [Accepted: 09/06/2021] [Indexed: 12/25/2022] Open
Abstract
Age-associated persistent ER stress is the result of declining chaperone systems of the ER that reduces cellular functions, induces apoptosis, and leads to age-related diseases. This study investigated the previously unknown regulatory mechanism of TMBIM6 during age-associated hepatic abnormalities. Wild-type (WT) and the TMBIM6 knockout (TMBIM6−/−) mice liver, human liver samples from different age groups were used to demonstrate the effect of physiological aging on liver. For TMBIM6 rescue experiments, TMBIM6−/− old mice and stable human hepatic cell lines expressing TMBIM 6 were used to study the functional role of TMBIM6 on aging-associated steatosis and its associated mechanisms. In aging humans and mice, we observed declined expression of TMBIM6 and aberrant UPR expression, which were associated with high hepatic lipid accumulation. During aging, TMBIM6-deficient mice had increased senescence than their WT counterparts. We identified redox-mediated posttranslational modifications of IRE1α such as S-nitrosylation and sulfonation were higher in TMBIM6-deficient aging mice and humans, which impaired the ER stress response signaling. Sulfonation of IRE1α enhanced regulated IRE1α-dependent decay (RIDD) activity inducing TMBIM6 decay, whereas S-nitrosylation of IRE1α inhibited XBP1 splicing enhancing the cell death. Moreover, the degradation of miR-338-3p by strong IRE1α cleavage activity enhanced the expression of PTP1B, resulting in diminishing phosphorylation of PERK. The re-expression of TMBIM6 reduced IRE1α modifications, preserved ER homeostasis, reduced senescence and senescence-associated lipid accumulation in human hepatic cells and TMBIM6-depleted mice. S-nitrosylation or sulfonation of IRE1α and its controller, the TMBIM6, might be the potential therapeutic targets for maintaining ER homeostasis in aging and aging-associated liver diseases. TMBIM6 is downregulated in fatty degeneration, and in aging human and mouse liver. TMBIM6 deficiency induces ER stress response failure and cell death and increases age-associated steatosis. TMBIM6 regulates redox-mediated cysteine modifications such as S-nitrosylation and sulfonation of IRE1α. IRE1α-SNO inhibits XBP1 splicing, whereas IRE1α-SO3H enhances RIDD activity inducing TMBIM6 decay. TMBIM6 overexpression attenuates hepatic steatosis by regulating ER stress and cysteine modifications caused by aging.
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Affiliation(s)
- Kashi Raj Bhattarai
- School of Pharmacy and Institute of New Drug Development, Jeonbuk National University, 54896, Jeonju, Republic of Korea; Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, 38105, Memphis, TN, USA
| | - Hyun-Kyoung Kim
- School of Pharmacy and Institute of New Drug Development, Jeonbuk National University, 54896, Jeonju, Republic of Korea
| | - Manoj Chaudhary
- Department of Pharmacology and Institute of New Drug Development, Jeonbuk National University Medical School, 54896, Jeonju, Republic of Korea
| | - Mohammad Mamun Ur Rashid
- Department of Pharmacology and Institute of New Drug Development, Jeonbuk National University Medical School, 54896, Jeonju, Republic of Korea
| | - Jisun Kim
- School of Pharmacy and Institute of New Drug Development, Jeonbuk National University, 54896, Jeonju, Republic of Korea
| | - Hyung-Ryong Kim
- Department of Dental Pharmacology, College of Dentistry, Jeonbuk National University, Jeonju, 54896, Republic of Korea.
| | - Han-Jung Chae
- School of Pharmacy and Institute of New Drug Development, Jeonbuk National University, 54896, Jeonju, Republic of Korea.
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CYP2E1 in Alcoholic and Non-Alcoholic Liver Injury. Roles of ROS, Reactive Intermediates and Lipid Overload. Int J Mol Sci 2021; 22:ijms22158221. [PMID: 34360999 PMCID: PMC8348366 DOI: 10.3390/ijms22158221] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/09/2021] [Accepted: 07/13/2021] [Indexed: 02/08/2023] Open
Abstract
CYP2E1 is one of the fifty-seven cytochrome P450 genes in the human genome and is highly conserved. CYP2E1 is a unique P450 enzyme because its heme iron is constitutively in the high spin state, allowing direct reduction of, e.g., dioxygen, causing the formation of a variety of reactive oxygen species and reduction of xenobiotics to toxic products. The CYP2E1 enzyme has been the focus of scientific interest due to (i) its important endogenous function in liver homeostasis, (ii) its ability to activate procarcinogens and to convert certain drugs, e.g., paracetamol and anesthetics, to cytotoxic end products, (iii) its unique ability to effectively reduce dioxygen to radical species causing liver injury, (iv) its capability to reduce compounds, often generating radical intermediates of direct toxic or indirect immunotoxic properties and (v) its contribution to the development of alcoholic liver disease, steatosis and NASH. In this overview, we present the discovery of the enzyme and studies in humans, 3D liver systems and genetically modified mice to disclose its function and clinical relevance. Induction of the CYP2E1 enzyme either by alcohol or high-fat diet leads to increased severity of liver pathology and likelihood to develop ALD and NASH, with subsequent influence on the occurrence of hepatocellular cancer. Thus, fat-dependent induction of the enzyme might provide a link between steatosis and fibrosis in the liver. We conclude that CYP2E1 has many important physiological functions and is a key enzyme for hepatic carcinogenesis, drug toxicity and liver disease.
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Auclair N, Sané AT, Ahmarani L, Patey N, Beaulieu JF, Peretti N, Spahis S, Levy E. Sar1b mutant mice recapitulate gastrointestinal abnormalities associated with chylomicron retention disease. J Lipid Res 2021; 62:100085. [PMID: 33964306 PMCID: PMC8175419 DOI: 10.1016/j.jlr.2021.100085] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/15/2021] [Accepted: 04/17/2021] [Indexed: 11/17/2022] Open
Abstract
Chylomicron retention disease (CRD) is an autosomal recessive disorder associated with biallelic Sar1b mutations leading to defects in intracellular chylomicron (CM) trafficking and secretion. To date, a direct cause-effect relationship between CRD and Sar1b mutation has not been established, but genetically modified animal models provide an opportunity to elucidate unrecognized aspects of these mutations. To examine the physiological role and molecular mechanisms of Sar1b function, we generated mice expressing either a targeted deletion or mutation of human Sar1b using the CRISPR-Cas9 system. We found that deletion or mutation of Sar1b in mice resulted in late-gestation lethality of homozygous embryos. Moreover, compared with WT mice, heterozygotes carrying a single disrupted Sar1b allele displayed lower plasma levels of triglycerides, total cholesterol, and HDL-cholesterol, along with reduced CM secretion following gastric lipid gavage. Similarly, decreased expression of apolipoprotein B and microsomal triglyceride transfer protein was observed in correlation with the accumulation of mucosal lipids. Inefficient fat absorption in heterozygotes was confirmed via an increase in fecal lipid excretion. Furthermore, genetically modified Sar1b affected intestinal lipid homeostasis as demonstrated by enhanced fatty acid β-oxidation and diminished lipogenesis through the modulation of transcription factors. This is the first reported mammalian animal model with human Sar1b genetic defects, which reproduces some of the characteristic CRD features and provides a direct cause-effect demonstration.
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Affiliation(s)
- Nickolas Auclair
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada; Department of Pharmacology & Physiology, Université de Montréal, Montreal, Quebec, Canada
| | - Alain T Sané
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada
| | - Lena Ahmarani
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada; Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Nathalie Patey
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada; Department of Pathology, Université de Montréal, Montreal, Quebec, Canada
| | - Jean-François Beaulieu
- Laboratory of Intestinal Physiopathology, Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Quebec, Canada
| | - Noel Peretti
- Department of Pediatric Gastroenterology-Hepatology and Nutrition, Laboratory INSERM 1060 Cardiovascular Metabolism Endocrinology and Nutrition CarMEN, Lyon, France
| | - Schohraya Spahis
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada; Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Emile Levy
- Research Center, CHU Ste-Justine, Université de Montréal, Montreal, Quebec, Canada; Department of Pharmacology & Physiology, Université de Montréal, Montreal, Quebec, Canada; Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada.
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6
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Ali A, Zhang Y, Fu M, Pei Y, Wu L, Wang R, Yang G. Cystathionine gamma-lyase/H 2S system suppresses hepatic acetyl-CoA accumulation and nonalcoholic fatty liver disease in mice. Life Sci 2020; 252:117661. [PMID: 32305523 DOI: 10.1016/j.lfs.2020.117661] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 04/05/2020] [Accepted: 04/08/2020] [Indexed: 02/07/2023]
Abstract
AIMS Hydrogen sulfide (H2S) as a novel gasotransmitter can be endogenously produced in liver by cystathionine gamma-lyase (CSE). The dysfunctions of CSE/H2S system have been linked to various liver diseases. Acetyl-CoA is the key intermediate from the metabolism of lipid. This study examined the roles of H2S in hepatic acetyl-CoA and lipid metabolism. MATERIALS AND METHODS Both in vitro cell model and in vivo animal model of lipid accumulation were used in this study. Western blotting and real-time PCR were used for analysis of protein and mRNA expression. Acetyl-CoA was analyzed by a coupled enzyme assay, and lipid accumulation was observed with Oil Red O staining. KEY FINDINGS Incubation of human liver carcinoma (HepG2) cells with a mixture of free fatty acids (FFAs) or high glucose reduced CSE expression and H2S production, promoted intracellular accumulation of acetyl-CoA and lipid. Supply of exogenous NaHS or cysteine reduced acetyl-CoA contents and lipid accumulation, while blockage of CSE activity promoted intracellular lipid accumulation. Furthermore, H2S blocked FFAs-induced transcriptions of de novo lipogenesis, inflammation, and fibrosis-related genes. In vivo, knockout of CSE gene stimulated more hepatic acetyl-CoA and lipid accumulation in mice induced by high-fat choline-deficient diet. The expressions of lipogenesis, inflammation, and fibrosis-related genes were significantly higher in liver tissues from CSE knockout mice when compared with wild-type mice. SIGNIFICANCE CSE/H2S system is indispensable for maintaining the homeostasis of acetyl-CoA and lipid accumulation and protecting from the development of inflammation and fibrosis in liver under excessive caloric ingestion.
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Affiliation(s)
- Amr Ali
- Department of Chemistry and Biochemistry, Canada; Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada
| | - Yanjie Zhang
- Department of Chemistry and Biochemistry, Canada; Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada; School of Life Science, Shanxi University, Taiyuan, China
| | - Ming Fu
- Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada; School of Human Kinetics, Laurentian University, Sudbury, Canada; Health Science North Research Institute, Sudbury, Canada
| | - Yanxi Pei
- School of Life Science, Shanxi University, Taiyuan, China
| | - Lingyun Wu
- Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada; School of Human Kinetics, Laurentian University, Sudbury, Canada; Health Science North Research Institute, Sudbury, Canada
| | - Rui Wang
- Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada
| | - Guangdong Yang
- Department of Chemistry and Biochemistry, Canada; Cardiovascular and Metabolic Research Unit, Laurentian University, Sudbury, Canada.
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Lebeaupin C, Blanc M, Vallée D, Keller H, Bailly-Maitre B. BAX inhibitor-1: between stress and survival. FEBS J 2020; 287:1722-1736. [PMID: 31841271 DOI: 10.1111/febs.15179] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/18/2019] [Accepted: 12/13/2019] [Indexed: 12/13/2022]
Abstract
Cellular gatekeepers are essential to maintain order within a cell and anticipate signals of stress to promote survival. BCL2 associated X, apoptosis regulator (BAX) inhibitor-1 (BI-1), also named transmembrane BAX inhibitor motif containing-6, is a highly conserved endoplasmic reticulum (ER) transmembrane protein. Originally identified as an inhibitor of BAX-induced apoptosis, its pro-survival properties have been expanded to include functions targeted against ER stress, calcium imbalance, reactive oxygen species accumulation, and metabolic dysregulation. Nevertheless, the structural biology and biochemical mechanism of action of BI-1 are still under debate. BI-1 has been implicated in several diseases, including chronic liver disease, diabetes, ischemia/reperfusion injury, neurodegeneration, and cancer. While most studies have demonstrated a beneficial role for BI-1 in the ubiquitous maintenance of cellular homeostasis, its expression in cancer cells seems most often to contribute to tumorigenesis and metastasis. Here, we summarize what is known about BI-1 and encourage future studies on BI-1's contribution to cellular life and death decisions to advocate its potential as a target for drug development and other therapeutic strategies.
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Affiliation(s)
- Cynthia Lebeaupin
- INSERM U1065, C3M, Université Côte d'Azur, Nice, France.,Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.,Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Marina Blanc
- INSERM U1065, C3M, Université Côte d'Azur, Nice, France
| | | | - Harald Keller
- INRA1355-CNRS7254, Université Côte d'Azur, Sophia Antipolis, France
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Lebeau PF, Byun JH, Platko K, MacDonald ME, Poon SV, Faiyaz M, Seidah NG, Austin RC. Diet-induced hepatic steatosis abrogates cell-surface LDLR by inducing de novo PCSK9 expression in mice. J Biol Chem 2019; 294:9037-9047. [PMID: 31004037 DOI: 10.1074/jbc.ra119.008094] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/09/2019] [Indexed: 12/11/2022] Open
Abstract
The worldwide prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing rapidly. Although this condition is generally benign, accumulating evidence now suggests that patients with NAFLD are also at increased risk of cardiovascular disease (CVD); the leading cause of death in developed nations. Despite the well-established role of the liver as a central regulator of circulating low-density lipoprotein (LDL) cholesterol levels, a known driver of CVD, the mechanism(s) by which hepatic steatosis contributes to CVD remains elusive. Interestingly, a recent study has shown that circulating proprotein convertase subtilisin/kexin type 9 (PCSK9) levels correlate positively with liver steatosis grade. Given that PCSK9 degrades the LDL receptor (LDLR) and prevents the removal of LDL from the blood into the liver, in the present study we examined the effect of hepatic steatosis on LDLR expression and circulating LDL cholesterol levels. We now report that in a manner consistent with findings in patients, diet-induced steatosis increases circulating PCSK9 levels as a result of de novo expression in mice. We also report the finding that steatosis abrogates hepatic LDLR expression and increases circulating LDL levels in a PCSK9-dependent manner. These findings provide important mechanistic insights as to how hepatic steatosis modulates lipid regulatory genes, including PCSK9 and the LDLR, and also highlights a novel mechanism by which liver disease may contribute to CVD.
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Affiliation(s)
- Paul F Lebeau
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Jae Hyun Byun
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Khrystyna Platko
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Melissa E MacDonald
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Samantha V Poon
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Mahi Faiyaz
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
| | - Nabil G Seidah
- the Laboratory of Biochemical Neuroendocrinology, Montreal Clinical Research Institute, University of Montreal, Montreal, Quebec H2W 1R7, Canada
| | - Richard C Austin
- From the Department of Medicine, McMaster University, The Research Institute of St. Joe's Hamilton, Hamilton, Ontario L8N 4A6 and
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9
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Kim HK, Yadav RK, Bhattarai KR, Jung HW, Kim HR, Chae HJ. Transmembrane BAX Inhibitor Motif-6 (TMBIM6) protects against cisplatin-induced testicular toxicity. Hum Reprod 2019; 33:378-389. [PMID: 29309588 DOI: 10.1093/humrep/dex381] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 12/18/2017] [Indexed: 12/20/2022] Open
Abstract
STUDY QUESTION Is the Transmembrane BAX Inhibitor Motif-6 (TMBIM6) involved in the molecular mechanism by which cisplatin causes reproductive toxicity? SUMMARY ANSWER TMBIM6 protects against cisplatin-induced testicular toxicity through up-regulation of heme oxygenase-1 (HO-1),-which maintains the levels of steroidogenic enzymes by decreaseing oxidative stress in the endoplasmic reticulum (ER). WHAT IS KNOWN ALREADY Testosterone production is highly suppressed as a main complication of cisplatin (cis-diamminedichloroplatinum) anticancer therapy. STUDY DESIGN, SIZE, DURATION Groups of seven wild type or Tmbim6 KO C57BL/6J mice were given a single i.p., injection of cisplatin (30 mg/kg body wt) and testis and serum were collected 3 days later. Tmbim6-lentivirus-mediated testicular expression-rescued KO mice were analyzed to confirm function was restored. Tmbim6-over expressing TM3 mouse Leydig cells were exposed to cisplatin in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS After collection of the specimens serum testosterone level and testicular weight and structure were compared between the groups. Quantitative PCR, immunoblot, and assays for ROS, HO-1 activity and protein disulfide isomerase (PDI) carbonylation were performed. MAIN RESULTS AND THE ROLE OF CHANCE Phospho protein kinase B (p-Akt), nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), and its downstream gene product HO-1 and the levels of testosterone synthesis-associated enzymes, including steroidogenic acute regulatory protein (StAR), a rate limiting enzyme for testosterone production, were significantly expressed in the presence of Tmbim6 and maintained after cisplatin treament. Excessive post-translational oxidation of protein disulfide isomerase (PDI), altered folding capacitance and ROS accumulation, and ER stress were also decreased in the presence of Tmbim6. Higher levels of ER stress and protein hypercarbonylation were consistently observed in KO testis, compared with WT testis. In the Tmbim6 KO mice, lentivirus-mediated testicular expression of Tmbim6 rescued the above phenotypes. Furthermore, the protective role of Tmbim6 against testicular toxicity was consistently shown in Tmbim6-overexpressing TM3 Leydig cells (testosterone producing cells). We conclude that TMBIM6 protects against cisplatin-induced testicular toxicity by inducing HO-1 and enhancing ER folding capacitance. LARGE SCALE DATA N/A. LIMITATIONS, REASONS FOR CAUTION This study was performed using a short, 3-day cisplatin treatment condition. Therefore, the results need to be cautiously interpreted with regard to cisplatin-associated chronic toxicity. Moreover, to determine the clinical relevance of the role of TMBIM6, further studies in testicular cancer are needed. WIDER IMPLICATIONS OF THE FINDINGS Cisplatin-associated ER stress and redox imbalance might be implicated as toxicity mechanisms associated with anticancer therapy. STUDY FUNDING/COMPETING INTEREST(S) This study was supported by the National Research Foundation of Korea (2015R1A2A1A13001849). The authors have no competing interests to disclose.
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Affiliation(s)
- Hyun-Kyoung Kim
- Department of Pharmacology and Institute of New Drug Development, Chonbuk National University, Jeonju 54689, Republic of Korea
| | - Raj Kumar Yadav
- Department of Pharmacology and Institute of New Drug Development, Chonbuk National University, Jeonju 54689, Republic of Korea
| | - Kashi Raj Bhattarai
- Department of Pharmacology and Institute of New Drug Development, Chonbuk National University, Jeonju 54689, Republic of Korea
| | - Han-Wool Jung
- Department of Pharmacology and Institute of New Drug Development, Chonbuk National University, Jeonju 54689, Republic of Korea
| | | | - Han-Jung Chae
- Department of Pharmacology and Institute of New Drug Development, Chonbuk National University, Jeonju 54689, Republic of Korea
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10
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Potential Application of Ixeris dentata in the Prevention and Treatment of Aging-Induced Dry Mouth. Nutrients 2018; 10:nu10121989. [PMID: 30558302 PMCID: PMC6316753 DOI: 10.3390/nu10121989] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/10/2018] [Accepted: 12/12/2018] [Indexed: 12/13/2022] Open
Abstract
Dry mouth is a common complaint among the elderly population. The aim of this study was to investigate the effect of Ixeris dentata (IXD) extract on aging-induced dry mouth. We used young (two months) and aged (20 months) SD rats in our study. Using water as the vehicle, IXD extract (25, 50, and 100 mg/kg) was given via oral gavage to the young and aged rats for eight weeks. We found that the salivary flow rate relative to the submandibular gland weight was differently influenced by IXD extract treatment. IXD extract augmented the submandibular gland acinar cells, which are depleted during aging. In addition, the decreased salivary alpha-amylase, inositol triphosphate receptor, and aquaporin-5 in the aging rats were upregulated by IXD treatment. Free radical-induced oxidative stress in the aging rats was also alleviated in the IXD-treated group. The formation of high molecular weight complexes of protein disulfide isomerase, decreased expression of an ER chaperone (GRP78), and increased ER stress response (ATF-4, CHOP and p-JNK) in aging rats was regulated with IXD treatment, and eventually increased salivary secretions from the aging submandibular glands. These are the first data to suggest that IXD extract might ameliorate aging-associated oral dryness by regulating the ER environment.
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Lebeaupin C, Vallée D, Hazari Y, Hetz C, Chevet E, Bailly-Maitre B. Endoplasmic reticulum stress signalling and the pathogenesis of non-alcoholic fatty liver disease. J Hepatol 2018; 69:927-947. [PMID: 29940269 DOI: 10.1016/j.jhep.2018.06.008] [Citation(s) in RCA: 640] [Impact Index Per Article: 91.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/22/2018] [Accepted: 06/14/2018] [Indexed: 12/13/2022]
Abstract
The global epidemic of obesity has been accompanied by a rising burden of non-alcoholic fatty liver disease (NAFLD), with manifestations ranging from simple steatosis to non-alcoholic steatohepatitis, potentially developing into hepatocellular carcinoma. Although much attention has focused on NAFLD, its pathogenesis remains largely obscure. The hallmark of NAFLD is the hepatic accumulation of lipids, which subsequently leads to cellular stress and hepatic injury, eventually resulting in chronic liver disease. Abnormal lipid accumulation often coincides with insulin resistance in steatotic livers and is associated with perturbed endoplasmic reticulum (ER) proteostasis in hepatocytes. In response to chronic ER stress, an adaptive signalling pathway known as the unfolded protein response is triggered to restore ER proteostasis. However, the unfolded protein response can cause inflammation, inflammasome activation and, in the case of non-resolvable ER stress, the death of hepatocytes. Experimental data suggest that the unfolded protein response influences hepatic tumour development, aggressiveness and response to treatment, offering novel therapeutic avenues. Herein, we provide an overview of the evidence linking ER stress to NAFLD and discuss possible points of intervention.
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Affiliation(s)
| | - Deborah Vallée
- Université Côte d'Azur, INSERM, U1065, C3M, 06200 Nice, France
| | - Younis Hazari
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO), Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile
| | - Claudio Hetz
- Biomedical Neuroscience Institute (BNI), Faculty of Medicine, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO), Santiago, Chile; Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, University of Chile, Santiago, Chile; Buck Institute for Research on Aging, Novato, CA 94945, USA; Department of Immunology and Infectious Diseases, Harvard School of Public Health, 02115 Boston, MA, USA
| | - Eric Chevet
- "Chemistry, Oncogenesis, Stress, Signaling", Inserm U1242, Université de Rennes, Rennes, France; Centre de Lutte Contre le Cancer Eugène Marquis, Rennes, France
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Bhattarai KR, Lee HY, Kim SH, Kim HR, Chae HJ. Ixeris dentata Extract Increases Salivary Secretion through the Regulation of Endoplasmic Reticulum Stress in a Diabetes-Induced Xerostomia Rat Model. Int J Mol Sci 2018; 19:ijms19041059. [PMID: 29614832 PMCID: PMC5979381 DOI: 10.3390/ijms19041059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 03/20/2018] [Accepted: 03/28/2018] [Indexed: 12/14/2022] Open
Abstract
This study aimed to investigate the molecular mechanism of diabetes mellitus (DM)-induced dry mouth and an application of natural products from Ixeris dentata (IXD), a recently suggested regulator of amylase secretion in salivary cells. Vehicle-treated or diabetic rats were orally treated with either water or an IXD extract for 10 days to observe the effect on salivary flow. We found that the IXD extract increased aquaporin 5 (AQP5) and alpha-amylase protein expression in the submandibular gland along with salivary flow rate. Similarly, the IXD extract and its purified compound increased amylase secretion in high glucose-exposed human salivary gland cells. Furthermore, increased endoplasmic reticulum stress response in the submandibular gland of diabetic rats was inhibited by treatment with the IXD extract, suggesting that IXD extract treatment improves the ER environment by increasing the protein folding capacity. Thus, pharmacological treatment with the IXD extract is suggested to relieve DM-induced dry mouth symptoms.
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Affiliation(s)
- Kashi Raj Bhattarai
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju 54896, Korea.
| | - Hwa-Young Lee
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju 54896, Korea.
| | - Seung-Hyun Kim
- College of Pharmacy, Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 406-840, Korea.
| | - Hyung-Ryong Kim
- Graduate School, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea.
| | - Han-Jung Chae
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju 54896, Korea.
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Lee HY, Zeeshan HMA, Kim HR, Chae HJ. Nox4 regulates the eNOS uncoupling process in aging endothelial cells. Free Radic Biol Med 2017; 113:26-35. [PMID: 28916474 DOI: 10.1016/j.freeradbiomed.2017.09.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/17/2017] [Accepted: 09/11/2017] [Indexed: 01/03/2023]
Abstract
ROS and its associated signaling contribute to vascular aging-associated endothelial disturbance. Since the non-effective endothelial nitric oxide synthase (eNOS) coupling status is related to vascular aging-related phenotypes, eNOS coupled/uncoupled system signaling was studied in human umbilical vein endothelial cells (HUVEC). Nitric oxide (NO) and eNOS Ser1177 were significantly decreased, whereas O2- (superoxide anion radical) increased with passage number. In aging cells, NADPH oxidase 4 (Nox4), one of the main superoxide generating enzymes, and its associated protein disulfide isomerase (PDI) chaperone were highly activated, and the resultant ER redox imbalance leads to disturbance of protein folding capability, namely endoplasmic reticulum (ER) stress, ultimately inducing dissociation between HSP90 and IRE-1α or PERK, decreasing HSP90 stability and dissociating the binding of eNOS from the HSP90 and leading to eNOS uncoupling. Through chemical and Nox4 siRNA approaches, Nox4 and its linked ER stress were shown to mainly contribute to eNOS uncoupling and its associated signaling, suggesting that Nox4 and its related ER stress signaling are key signals of the aging process in endothelial cells.
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Affiliation(s)
- Hwa-Young Lee
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju, Chonbuk, South Korea
| | - Hafiz Maher Ali Zeeshan
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju, Chonbuk, South Korea
| | - Hyung-Ryong Kim
- Daegu Gyeonbuk Institute of Science & Technology (DGIST) Graduate School, Daegu, South Korea
| | - Han-Jung Chae
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju, Chonbuk, South Korea.
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Bhattarai KR, Lee SW, Kim SH, Kim HR, Chae HJ. Ixeris dentata extract regulates salivary secretion through the activation of aquaporin-5 and prevents diabetes-induced xerostomia. J Exp Pharmacol 2017; 9:81-91. [PMID: 28814903 PMCID: PMC5546769 DOI: 10.2147/jep.s141807] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The aim of this study was to investigate the effects of Ixeris dentata (IXD) extract to improve the salivation rate in dry mouth induced by diabetes. Both control and diabetic rats were treated with a sublingual spray of either water or IXD extract to determine the effects of IXD on salivation. During the study, we observed that IXD extract treatment increased the salivary flow rate in diabetic rats. The expression of α-amylase was increased significantly in both saliva and glandular tissue lysates of IXD-treated diabetic rats. Aquaporin-5 protein expression was abnormally low in the salivary glands of diabetic rats, which increased hyposalivation and led to salivary dysfunction. However, a single oral spray of IXD extract drastically increased the expression of aquaporin-5 in salivary gland acinar and ductal cells in diabetic rats. Moreover, IXD extract induced expression of Na+/H+ exchangers in the salivary gland, which suggests that Na+/H+ exchangers modulate salivary secretions and aid in the fluid-secretion mechanism. Furthermore, transient treatment with IXD extract increased the intracellular calcium in human salivary gland cells. Taken together, these results suggest the potential value of an IXD extract for the treatment of diabetes-induced hyposalivation and xerostomia.
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Affiliation(s)
- Kashi Raj Bhattarai
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju
| | - Sang-Won Lee
- Department of Herb Crop Resources, National Institute of Horticultural and Herbal Science, Rural Development Administration, Eumseong-gun
| | - Seung Hyun Kim
- College of Pharmacy, Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon
| | - Hyung-Ryong Kim
- Graduate School, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Han-Jung Chae
- Department of Pharmacology and Institute of New Drug Development, School of Medicine, Chonbuk National University, Jeonju
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