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Han S, Zeng Y, Li Y, Li H, Yang L, Ren X, Lan M, Wang B, Song X. Carbon Monoxide: A Second Biomarker to Couple with Viscosity for the Construction of "Dual-Locked" Near-Infrared Fluorescent Probes for Accurately Diagnosing Non-Alcoholic Fatty Liver Disease. Anal Chem 2023; 95:18619-18628. [PMID: 38054238 DOI: 10.1021/acs.analchem.3c04676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) can progress to cirrhosis and liver cancer if left untreated. Therefore, it is of great importance to develop useful tools for the noninvasive and accurate diagnosis of NAFLD. Increased microenvironmental viscosity was considered as a biomarker of NAFLD, but the occurrence of increased viscosity in other liver diseases highly reduces the diagnosis accuracy of NAFLD by a single detection of viscosity. Hence, it is very necessary to seek a second biomarker of NAFLD. It has been innovatively proposed that the overexpressed heme oxygenase-1 enzyme in NAFLD would produce abnormally high concentrations of CO in hepatocytes and that CO could serve as a potential biomarker. In this work, we screened nine lactam Changsha dyes (HCO-1-HCO-9) with delicate structures to obtain near-infrared (NIR), metal-free, and "dual-locked" fluorescent probes for the simultaneous detection of CO and viscosity. Changsha dyes with a 2-pyridinyl hydrazone substituent could sense CO, and the 5-position substituents on the 2-pyridinyl moiety had a great electron effect on the reaction rate. The double bond in these dyes served as the sensing group for viscosity. Probe HCO-9 was utilized for precise diagnosis of NAFLD by simultaneous detection of CO and viscosity. Upon reacting with CO in a high-viscosity microenvironment, strong fluorescence at 745 nm of probe HCO-9 was turned on with NIR excitation at 700 nm. Probe HCO-9 was proven to be an effective tool for imaging CO and viscosity. Due to the advantages of NIR absorption and low toxicity, probe HCO-9 was successfully applied to image NAFLD in a mouse model.
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Affiliation(s)
- Shaohui Han
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Yuyang Zeng
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Yiling Li
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Haipu Li
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Lei Yang
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry & Chemical Engineering, Linyi University, Linyi, Shandong 276000, China
| | - Xiaojie Ren
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
- Department of Chemistry and Centre of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong 999077, China
| | - Minhuan Lan
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Benhua Wang
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
| | - Xiangzhi Song
- College of Chemistry & Chemical Engineering, Central South University, Changsha, Hunan 410083, China
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Wang H, Nikain C, Amengual J, La Forest M, Yu Y, Wang MC, Watts R, Lehner R, Qiu Y, Cai M, Kurland IJ, Goldberg IJ, Rajan S, Hussain MM, Brodsky JL, Fisher EA. FITM2 deficiency results in ER lipid accumulation, ER stress, reduced apolipoprotein B lipidation, and VLDL triglyceride secretion in vitro and in mouse liver. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.05.570183. [PMID: 38106013 PMCID: PMC10723279 DOI: 10.1101/2023.12.05.570183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Objectives Triglyceride (TG) association with apolipoprotein B100 (apoB100) serves to form very low density lipoproteins (VLDL) in the liver. The repertoire of factors that facilitate this association is incompletely defined. FITM2, an integral endoplasmic reticulum (ER) protein, was originally discovered as a factor participating in cytoplasmic lipid droplets (LDs) in tissues that do not form VLDL. We hypothesized that in the liver, in addition to promoting cytosolic LD formation, FITM2 would also transfer TG from its site of synthesis in the ER membrane to nascent VLDL particles within the ER lumen. Methods Experiments were conducted using a rat hepatic cell line (McArdle-RH7777, or McA cells), an established model of mammalian lipoprotein metabolism, and mice. FITM2 expression was reduced using siRNA in cells and by liver specific cre-recombinase mediated deletion of the Fitm2 gene in mice. Effects of FITM2 deficiency on VLDL assembly and secretion in vitro and in vivo were measured by multiple methods, including density gradient ultracentrifugation, chromatography, mass spectrometry, simulated Raman spectroscopy (SRS) microscopy, sub-cellular fractionation, immunoprecipitation, immunofluorescence, and electron microscopy. Main findings 1) FITM2-deficient hepatic cells in vitro and in vivo secrete TG-depleted VLDL particles, but the number of particles is unchanged compared to controls; 2) FITM2 deficiency in mice on a high fat diet (HFD) results in decreased plasma TG levels. The number of apoB100-containing lipoproteins remains similar, but shift from VLDL to LDL density; 3) Both in vitro and in vivo , when TG synthesis is stimulated and FITM2 is deficient, TG accumulates in the ER, and despite its availability this pool is unable to fully lipidate apoB100 particles; 4) FITM2 deficiency disrupts ER morphology and results in ER stress. Principal conclusions The results suggest that FITM2 contributes to VLDL lipidation, especially when newly synthesized hepatic TG is in abundance. In addition to its fundamental importance in VLDL assembly, the results also suggest that under dysmetabolic conditions, FITM2 may be a limiting factor that ultimately contributes to non-alcoholic fatty liver disease (NAFLD) and steatohepatitis (NASH).
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Jung EJ, Sung KW, Bae TH, Kim HY, Choi HR, Kim SH, Jung CH, Mun SR, Son YS, Kim S, Suh YH, Kashina A, Park JW, Kwon YT. The N-degron pathway mediates lipophagy: The chemical modulation of lipophagy in obesity and NAFLD. Metabolism 2023; 146:155644. [PMID: 37385404 PMCID: PMC10529862 DOI: 10.1016/j.metabol.2023.155644] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/23/2023] [Accepted: 06/24/2023] [Indexed: 07/01/2023]
Abstract
BACKGROUND AND AIMS Central to the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is the accumulation of lipids in the liver and various fat tissues. We aimed to elucidate the mechanisms by which lipid droplets (LDs) in the liver and adipocytes are degraded by the autophagy-lysosome system and develop therapeutic means to modulate lipophagy, i.e., autophagic degradation of LDs. METHODS We monitored the process in which LDs are pinched off by autophagic membranes and degraded by lysosomal hydrolases in cultured cells and mice. The autophagic receptor p62/SQSTM-1/Sequestosome-1 was identified as a key regulator and used as a target to develop drugs to induce lipophagy. The efficacy of p62 agonists was validated in mice to treat hepatosteatosis and obesity. RESULTS We found that the N-degron pathway modulates lipophagy. This autophagic degradation initiates when the molecular chaperones including BiP/GRP78, retro-translocated from the endoplasmic reticulum, is N-terminally (Nt-) arginylated by ATE1 R-transferase. The resulting Nt-arginine (Nt-Arg) binds the ZZ domain of p62 associated with LDs. Upon binding to Nt-Arg, p62 undergoes self-polymerization and recruits LC3+ phagophores to the site of lipophagy, leading to lysosomal degradation. Liver-specific Ate1 conditional knockout mice under high fat diet developed severe NAFLD. The Nt-Arg was modified into small molecule agonists to p62 that facilitate lipophagy in mice and exerted therapeutic efficacy in obesity and hepatosteatosis of wild-type but not p62 knockout mice. CONCLUSIONS Our results show that the N-degron pathway modulates lipophagy and provide p62 as a drug target to treat NAFLD and other diseases related with metabolic syndrome.
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Affiliation(s)
- Eui Jung Jung
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Ki Woon Sung
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; AUTOTAC Bio Inc., Changgyeonggung-Ro 254, Jongno-Gu, Seoul, 03077, Republic of Korea
| | - Tae Hyun Bae
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Hee-Yeon Kim
- Department of Biochemistry, College of Medicine, Ewha Womans University, Seoul, 07804, Republic of Korea
| | - Ha Rim Choi
- Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Sung Hyun Kim
- AUTOTAC Bio Inc., Changgyeonggung-Ro 254, Jongno-Gu, Seoul, 03077, Republic of Korea
| | - Chan Hoon Jung
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Su Ran Mun
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Yeon Sung Son
- Neuroscience Research Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Shin Kim
- Department of Immunology, School of Medicine, Keimyung University, Daegu, 42601, Republic of Korea
| | - Young Ho Suh
- Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Neuroscience Research Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea
| | - Anna Kashina
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, United States
| | - Joo-Won Park
- Department of Biochemistry, College of Medicine, Ewha Womans University, Seoul, 07804, Republic of Korea.
| | - Yong Tae Kwon
- Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; AUTOTAC Bio Inc., Changgyeonggung-Ro 254, Jongno-Gu, Seoul, 03077, Republic of Korea; Convergence Research Center for Dementia, Seoul National University Medical Research Center, Seoul, 03080, Republic of Korea; Ischemic/Hypoxic Disease Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea.
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Yang C, Yang L, Yang L, Li S, Ye L, Ye J, Chen C, Zeng Y, Zhu M, Lin X, Peng Q, Wang Y, Jin M. Plasma Proteomics Study Between the Frequent Exacerbation and Infrequent Exacerbation Phenotypes of Chronic Obstructive Pulmonary Disease. Int J Chron Obstruct Pulmon Dis 2023; 18:1713-1728. [PMID: 37581107 PMCID: PMC10423573 DOI: 10.2147/copd.s408361] [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: 02/21/2023] [Accepted: 07/09/2023] [Indexed: 08/16/2023] Open
Abstract
Background Frequent exacerbation (FE) and infrequent exacerbation (IE) are two phenotypes of chronic obstructive pulmonary disease (COPD), of which FE is associated with a higher incidence of exacerbation and a serious threat to human health. Because the pathogenesis mechanisms of FE are unclear, this study aims to identify FE-related proteins in the plasma via proteomics for use as predictive, diagnostic, and therapeutic biomarkers of COPD. Methods A cross-sectional study was conducted in which plasma protein profiles were analyzed in COPD patients at stable stage, and differentially expressed proteins (DEPs) were screened out between the FE and IE patients. FE-related DEPs were identified using data-independent acquisition-based proteomics and bioinformatics analyses. In addition, FE-related candidates were verified by enzyme-linked immunosorbent assay. Results In this study, 47 DEPs were screened out between the FE and IE groups, including 20 upregulated and 27 downregulated proteins. Key biological functions (eg, neutrophil degranulation, extracellular exosome, protein homodimerization activity) and signaling pathways (eg, arginine and proline metabolism) were enriched in association with the FE phenotype. Receiver operating characteristic (ROC) analysis of the 11 combined DEPs revealed an area under the curve of 0.985 (p <0.05) for discriminating FE from IE. Moreover, correlation and ROC curve analyses indicated that creatine kinase, M-type (CKM) and fat storage-inducing transmembrane protein 1 (FITM1) might be clinically significant in patients with the FE phenotype. In addition, plasma expression levels of CKM and FITM1 were validated to be significantly decreased in the FE group compared with the IE group (CKM: p <0.01; FITM1: p <0.05). Conclusion In this study, novel insights into COPD pathogenesis were provided by investigating and comparing plasma protein profiles between the FE and IE patients. CKM, FITM1, and a combinative biomarker panel may serve as useful tools for assisting in the precision diagnosis and effective treatment of the FE phenotype of COPD.
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Affiliation(s)
- Chengyu Yang
- Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
- Department of Pulmonary and Critical Care Medicine, Huadong Hospital, Fudan University, Shanghai, 200040, People’s Republic of China
| | - Li Yang
- Department of Pulmonary and Critical Care Medicine, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325015, People’s Republic of China
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325015, People’s Republic of China
| | - Lei Yang
- Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, Guangdong, 518055, People’s Republic of China
| | - Shuiming Li
- Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, Guangdong, 518055, People’s Republic of China
| | - Ling Ye
- Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
- Department of Allergy, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
| | - Jinfeng Ye
- Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, Guangdong, 518055, People’s Republic of China
| | - Chengshui Chen
- Department of Pulmonary and Critical Care Medicine, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325015, People’s Republic of China
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325015, People’s Republic of China
- Department of Pulmonary and Critical Care Medicine, the Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People’s Hospital, Zhejiang, 324000, People’s Republic of China
| | - Yiming Zeng
- Department of Pulmonary and Critical Care Medicine, the Second Affiliated Hospital of Fujian Medical University, Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian, 362000, People’s Republic of China
| | - Mengchan Zhu
- Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
| | - Xiaoping Lin
- Department of Pulmonary and Critical Care Medicine, the Second Affiliated Hospital of Fujian Medical University, Respiratory Medicine Center of Fujian Province, Quanzhou, Fujian, 362000, People’s Republic of China
| | - Qing Peng
- Department of Pulmonary and Critical Care Medicine, Minhang Hospital, Fudan University, Shanghai, 201199, People’s Republic of China
| | - Yun Wang
- Longhua Innovation Institute for Biotechnology, Shenzhen University, Shenzhen, Guangdong, 518055, People’s Republic of China
- Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou, Guangdong, 515041, People’s Republic of China
| | - Meiling Jin
- Department of Pulmonary and Critical Care Medicine, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
- Department of Allergy, Zhongshan Hospital, Fudan University, Shanghai, 200032, People’s Republic of China
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Huang YW, Wang LT, Zhang M, Nie Y, Yang JB, Meng WL, Wang XJ, Sheng J. Caffeine can alleviate non-alcoholic fatty liver disease by augmenting LDLR expression via targeting EGFR. Food Funct 2023; 14:3269-3278. [PMID: 36916513 DOI: 10.1039/d2fo02701a] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
Increasing low-density lipoprotein receptor (LDLR) protein levels represents a key strategy for the prevention and treatment. Berberine can reportedly alleviate non-alcoholic fatty liver disease (NAFLD) by increasing the LDLR expression in an ERK1/2 signaling-dependent manner of NAFLD. Studies have shown that caffeine can inhibit fat deposition in the livers of mice; however, caffeine has not been reported to alleviate NAFLD by augmenting the LDLR expression via targeting EGFR. Here, an MTT assay, western blotting, RT-qPCR, immunohistochemistry, and surface plasmon resonance (SPR) analysis were used to investigate the role of caffeine in low-density lipoprotein cholesterol (LDL-C) clearance both in vitro and in vivo. In vitro, we found that caffeine could activate the EGFR-ERK1/2 signaling pathway in HepG2 cells, leading to increased LDLR mRNA and protein expression, and this effect could be inhibited by cetuximab. The SPR assay results have indicated that caffeine may increase the LDLR expression by directly binding to the EGFR extracellular domain and activating the EGFR-ERK1/2 signaling pathway. In vivo, caffeine markedly improved fatty liver and related blood indices in ApoE KO mice with high-fat-diet-induced NAFLD. Consistent with our in vitro results, we found that caffeine could also activate EGFR-ERK1/2 signaling and promote the LDLR expression in ApoE KO mice. In summary, caffeine can enhance the LDLR expression by directly binding to EGFR and activating the EGFR-ERK1/2 signaling pathway. EGFR signaling may represent a novel target for the prevention and treatment of NAFLD.
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Affiliation(s)
- Ye-Wei Huang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Science, Yunnan Agricultural University, Kunming, 650201, China
| | - Li-Tian Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, China
| | - Meng Zhang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, China
| | - Yan Nie
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, China
| | - Jin-Bo Yang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, China
| | - Wen-Luer Meng
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Food Science and Technology, Yunnan Agricultural University, Kunming, 650201, China
| | - Xuan-Jun Wang
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,College of Science, Yunnan Agricultural University, Kunming, 650201, China
| | - Jun Sheng
- Key Laboratory of Pu-er Tea Science, Ministry of Education, Yunnan Agricultural University, Kunming, 650201, China. .,State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Kunming, 650201, China
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Wang G, Chen A, Wu Y, Wang D, Chang C, Yu G. Fat storage-inducing transmembrane proteins: beyond mediating lipid droplet formation. Cell Mol Biol Lett 2022; 27:98. [DOI: 10.1186/s11658-022-00391-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 09/23/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractFat storage-inducing transmembrane proteins (FITMs) were initially identified in 2007 as members of a conserved endoplasmic reticulum (ER) resident transmembrane protein gene family, and were found to be involved in lipid droplet (LD) formation. Recently, several studies have further demonstrated that the ability of FITMs to directly bind to triglyceride and diacylglycerol, and the diphosphatase activity of hydrolyzing fatty acyl-CoA, might enable FITMs to maintain the formation of lipid droplets, engage in lipid metabolism, and protect against cellular stress. Based on the distribution of FITMs in tissues and their important roles in lipid droplet biology and lipid metabolism, it was discovered that FITMs were closely related to muscle development, adipocyte differentiation, and energy metabolism. Accordingly, the abnormal expression of FITMs was not only associated with type 2 diabetes and lipodystrophy, but also with cardiac disease and several types of cancer. This study reviews the structure, distribution, expression regulation, and functionality of FITMs and their potential relationships with various metabolic diseases, hoping to provide inspiration for fruitful research directions and applications of FITM proteins. Moreover, this review will provide an important theoretical basis for the application of FITMs in the diagnosis and treatment of related diseases.
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Liu H, Wang T, Chen X, Jiang J, Song N, Li R, Xin Y, Xuan S. Retraction Statement: Inhibition of miR-499-5p expression improves nonalcoholic fatty liver disease. Ann Hum Genet 2022; 86:369. [PMID: 31960406 PMCID: PMC9787480 DOI: 10.1111/ahg.12374] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 11/04/2019] [Accepted: 12/09/2019] [Indexed: 12/30/2022]
Affiliation(s)
- Hanyun Liu
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Ting Wang
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Xi Chen
- Department of Gastroenterology, Yantai Municipal Laiyang Central Hospital, Yantai, Shandong Province, China
| | - Jing Jiang
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Nianhua Song
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Ran Li
- Department of Infectious Diseases, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Yongning Xin
- Department of Gastroenterology, Qingdao Municipal Hospital, Qingdao, Shandong Province, China
| | - Shiying Xuan
- Department of Gastroenterology, Qingdao Municipal Hospital, Qingdao, Shandong Province, China.,Medical College of Qingdao University, Qingdao, Shandong Province, China
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Soundharrajan I, Karnan M, Jung JS, Lee KD, Lee JC, Ramesh T, Kim D, Choi KC. A Transcriptomic Response to Lactiplantibacillus plantarum-KCC48 against High-Fat Diet-Induced Fatty Liver Diseases in Mice. Int J Mol Sci 2022; 23:ijms23126750. [PMID: 35743193 PMCID: PMC9224190 DOI: 10.3390/ijms23126750] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/15/2022] [Accepted: 06/15/2022] [Indexed: 02/05/2023] Open
Abstract
The most prevalent chronic liver disorder in the world is fatty liver disease caused by a high-fat diet. We examined the effects of Lactiplantibacillus plantarum-KCC48 on high-fat diet-induced (HFD) fatty liver disease in mice. We used the transcriptome tool to perform a systematic evaluation of hepatic mRNA transcripts changes in high-fat diet (HFD)-fed animals and high-fat diet with L. plantarum (HFLPD)-fed animals. HFD causes fatty liver diseases in animals, as evidenced by an increase in TG content in liver tissues compared to control animals. Based on transcriptome data, 145 differentially expressed genes (DEGs) were identified in the liver of HFD-fed mice compared to control mice. Moreover, 61 genes were differentially expressed in the liver of mice fed the HFLPD compared to mice fed the HFD. Additionally, 43 common DEGs were identified between HFD and HFLPD. These genes were enriched in metabolic processes, retinol metabolism, the PPAR signaling pathway, fatty acid degradation, arachidonic metabolism, and steroid hormone synthesis. Taking these data into consideration, it can be concluded that L. plantarum-KCC48 treatment significantly regulates the expression of genes involved in hepatosteatosis caused by HFD, which may prevent fatty liver disease.
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Affiliation(s)
- Ilavenil Soundharrajan
- Grassland and Forage Division, Rural Development Administration, National Institute of Animal Science, Cheonan 31000, Korea; (I.S.); (M.K.); (J.-S.J.)
| | - Muthusamy Karnan
- Grassland and Forage Division, Rural Development Administration, National Institute of Animal Science, Cheonan 31000, Korea; (I.S.); (M.K.); (J.-S.J.)
| | - Jeong-Sung Jung
- Grassland and Forage Division, Rural Development Administration, National Institute of Animal Science, Cheonan 31000, Korea; (I.S.); (M.K.); (J.-S.J.)
| | - Kyung-Dong Lee
- Department of Companion Animals, Dongsin University, Naju 58245, Korea;
| | - Jeong-Chae Lee
- Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Jeonbuk National University, Jeonju 54896, Korea;
| | - Thiyagarajan Ramesh
- Department of Basic Medical Sciences, College of Medicine, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia;
| | - Dahye Kim
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, Wanju 55365, Korea
- Correspondence: (D.K.); (K.-C.C.); Tel.: +82-41-580-6752 (D.K.); Fax: +82-41-580-6779 (K.-C.C.)
| | - Ki-Choon Choi
- Grassland and Forage Division, Rural Development Administration, National Institute of Animal Science, Cheonan 31000, Korea; (I.S.); (M.K.); (J.-S.J.)
- Correspondence: (D.K.); (K.-C.C.); Tel.: +82-41-580-6752 (D.K.); Fax: +82-41-580-6779 (K.-C.C.)
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Down-Regulating the High Level of 17-Beta-Hydroxysteroid Dehydrogenase 13 Plays a Therapeutic Role for Non-Alcoholic Fatty Liver Disease. Int J Mol Sci 2022; 23:ijms23105544. [PMID: 35628360 PMCID: PMC9146021 DOI: 10.3390/ijms23105544] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 04/27/2022] [Accepted: 05/13/2022] [Indexed: 02/01/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide, and there is no specific drug to treat it. Recent results showed that 17-beta-hydroxysteroid dehydrogenase type 13 (HSD17B13) is associated with liver diseases, but these conclusions are controversial. Here, we showed that HSD17B13 was more highly expressed in the livers of NAFLD patients, and high expression was induced in the livers of murine NAFLD models and cultural hepatocytes treated using various etiologies. The high HSD17B13 expression in the hepatocytes facilitated the progression of NAFLD by directly stabilizing the intracellular lipid drops and by indirectly activating hepatic stellate cells. When HSD17B13 was overexpressed in the liver, it aggravated liver steatosis and fibrosis in mice fed with a high-fat diet, while down-regulated the high expression of HSD17B13 by short hairpin RNAs produced a therapeutic effect in the NAFLD mice. We concluded that high HSD17B13 expression is a good target for the development of drugs to treat NAFLD.
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Lee HW, Lee IJ, Lee SJ, Kim YR, Kim HM. Highly Sensitive Two-Photon Lipid Droplet Tracker for In Vivo Screening of Drug Induced Liver Injury. ACS Sens 2022; 7:1027-1035. [PMID: 35385270 DOI: 10.1021/acssensors.1c02679] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lipid droplets (LDs) are lipid-abundant organelles found in most cell lines and primarily consist of neutral lipids. They serve as a repository of various lipids and are associated with many cellular metabolic processes, including energy storage, membrane synthesis, and protein homeostasis. LDs are prominent in a variety of diseases related to lipid regulation, including obesity, fatty liver disease, diabetes, and atherosclerosis. To monitor LD dynamics in live samples, we developed a highly selective two-photon fluorescent tracker for LDs (LD1). It exhibited outstanding sensitivity with a remarkable two-photon-action cross section (Φδmax > 600 GM), photostability, and low cytotoxicity. In human hepatocytes and in vivo mouse liver tissue imaging, LD1 showed very bright fluorescence with high LD selectivity and minimized background signal to evaluate the stages of nonalcoholic fatty liver disease. Interestingly, we demonstrated that the liver sinusoid morphology became narrower with increasing LD size and visualized the dynamics including fusion of the LDs in vivo. Moreover, real-time and dual-color TPM imaging with LD1 and a two-photon lysosome tracker could be a useful predictive screening tool in the drug development process to monitor impending drug-induced liver injury inducing drug candidates.
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Affiliation(s)
- Hyo Won Lee
- Department of Energy Systems Research and Department of Chemistry, Ajou University, Suwon 16499, Korea
| | - In-Jeong Lee
- Three-Dimensional Immune System Imaging Core Facility, Ajou University, Suwon 16499, Korea
| | - Soo-Jin Lee
- Three-Dimensional Immune System Imaging Core Facility, Ajou University, Suwon 16499, Korea
| | - Yu Rim Kim
- Three-Dimensional Immune System Imaging Core Facility, Ajou University, Suwon 16499, Korea
| | - Hwan Myung Kim
- Department of Energy Systems Research and Department of Chemistry, Ajou University, Suwon 16499, Korea
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11
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Jing Y, Liu G, Zhang C, Yu B, Sun J, Lin D, Qu J. Lipophilic Red-Emitting Carbon Dots for Detecting and Tracking Lipid Droplets in Live Cells. ACS APPLIED BIO MATERIALS 2022; 5:1187-1193. [PMID: 35195413 DOI: 10.1021/acsabm.1c01230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lipid droplets (LDs), a dynamic organelle, are of vital importance in regulating the storage of neutral lipids and energy homeostasis. The aberrant expression of LDs is found to be highly associated with diverse metabolic diseases. Thus, detecting and monitoring LDs are essential to study the pathological and physiological processes of LDs in living bodies. However, it remains challenging to obtain suitable imaging probes to track LDs in vivo. Fortunately, the emergence of carbon dots (CDs), which are fluorescent nanomaterials with good biocompatibility and high stability, has provided us an unprecedented choice. In this work, CDs were synthesized via a solvothermal treatment of commercial reagents, 3-dimethylaminophenol. Interestingly, the prepared CDs show an intense red emission in non-hydrogen-bonding solution and have strong LD-targeting ability without any postmodification of ligands. Moreover, due to their low phototoxicity and excellent photostability, CDs were successfully applied to track the dynamics of LDs in live cells and image LDs in different cell lines and lipid-rich tissues. Overall, this work here proposed an LD-specific red-emitting CD probe, which will be of great value for learning more about LD-associated behaviors and diseases.
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Affiliation(s)
- Yingying Jing
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Center for Biomedical Photonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Guoyong Liu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China
| | - Chenshuang Zhang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Center for Biomedical Photonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Bin Yu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Center for Biomedical Photonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Jian Sun
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China
| | - Danying Lin
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Center for Biomedical Photonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Junle Qu
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Center for Biomedical Photonics, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
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12
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Lipid droplets associated perilipins protein insights into finding a therapeutic target approach to cure non-alcoholic fatty liver disease (NAFLD). FUTURE JOURNAL OF PHARMACEUTICAL SCIENCES 2022. [DOI: 10.1186/s43094-021-00395-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Abstract
Background
Non-alcoholic fatty liver disease (NAFLD) is now the most common form of chronic liver disease in the world, and it’s linked to a slew of other risk factors including diabetes, obesity, dysbiosis and inflammatory bowel disease. More than 30 years ago, a patient was diagnosed with fatty liver with excessive fat accumulation in hepatocytes, a disorder known as hepatosteatosis. There will be no promising therapeutic medicines available from 1980 to 2021 which can reverse the fatty liver to normal liver state. In this review, we highlighted on lipid droplet associated protein which play a major role in accumulation of fat in liver cells and how these cellular pathway could be a promising therapeutic approach to treat the fatty liver disease.
Main body
Over the last few decades, Western countries follow a high-fat diet and change their lifestyle pattern due to certain metabolic disorders prevalence rate is very high all over the world. NAFLD is a major health issue and burden globally nowadays. Researchers are trying to find out the potential therapeutic target to combat the disease. The exact pathophysiology of the disease is still unclear. In the present decades. There is no Food and Drug Administration approved drugs are available to reverse the chronic condition of the disease. Based on literature survey, lipid droplets and their associated protein like perilipins play an eminent role in body fat regulation. In this review, we explain all types of perilipins such as perilipin1-5 (PLIN1-5) and their role in the pathogenesis of fatty liver which will be helpful to find the novel pharmacological target to treat the fatty liver.
Conclusion
In this review, majorly focussed on how fat is get deposited into hepatocytes follow the cellular signalling involved during lipid droplet biogenesis and leads to NAFLD. However, up to date still there mechanism of action is unclear. In this review, we hypothesized that lipid droplets associated proteins like perilipins could be better pharmacological target to reverse the chronic stage of fatty liver disease and how these lipid droplets associated proteins hide a clue to maintain the normal lipid homeostasis in the human body.
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13
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Pu Q, Guo K, Lin P, Wang Z, Qin S, Gao P, Combs C, Khan N, Xia Z, Wu M. Bitter receptor TAS2R138 facilitates lipid droplet degradation in neutrophils during Pseudomonas aeruginosa infection. Signal Transduct Target Ther 2021; 6:210. [PMID: 34083514 PMCID: PMC8175399 DOI: 10.1038/s41392-021-00602-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 03/04/2021] [Accepted: 04/01/2021] [Indexed: 02/05/2023] Open
Abstract
Bitter receptors function primarily in sensing taste, but may also have other functions, such as detecting pathogenic organisms due to their agile response to foreign objects. The mouse taste receptor type-2 member 138 (TAS2R138) is a member of the G-protein-coupled bitter receptor family, which is not only found in the tongue and nasal cavity, but also widely distributed in other organs, such as the respiratory tract, gut, and lungs. Despite its diverse functions, the role of TAS2R138 in host defense against bacterial infection is largely unknown. Here, we show that TAS2R138 facilitates the degradation of lipid droplets (LDs) in neutrophils during Pseudomonas aeruginosa infection through competitive binding with PPARG (peroxisome proliferator-activated receptor gamma) antagonist: N-(3-oxododecanoyl)-L-homoserine lactone (AHL-12), which coincidently is a virulence-bound signal produced by this bacterium (P. aeruginosa). The released PPARG then migrates from nuclei to the cytoplasm to accelerate the degradation of LDs by binding PLIN2 (perilipin-2). Subsequently, the TAS2R138-AHL-12 complex targets LDs to augment their degradation, and thereby facilitating the clearance of AHL-12 in neutrophils to maintain homeostasis in the local environment. These findings reveal a crucial role for TAS2R138 in neutrophil-mediated host immunity against P. aeruginosa infection.
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Affiliation(s)
- Qinqin Pu
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
| | - Kai Guo
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA
| | - Ping Lin
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
- Wound Trauma Medical Center, State Key Laboratory of Trauma, Burns and Combined Injury, Daping Hospital, Army Medical University, Chongqing, China
- Biological Science Research Center, Southwest University, Chongqing, 400716, China
| | - Zhihan Wang
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
- West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, Sichuan, China
| | - Shugang Qin
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, Sichuan, China
| | - Pan Gao
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
| | - Colin Combs
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA
| | - Nadeem Khan
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA.
| | - Zhenwei Xia
- Department of Pediatrics, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
| | - Min Wu
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, USA.
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14
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Chen F, Yan B, Ren J, Lyu R, Wu Y, Guo Y, Li D, Zhang H, Hu J. FIT2 organizes lipid droplet biogenesis with ER tubule-forming proteins and septins. J Cell Biol 2021; 220:211999. [PMID: 33861319 PMCID: PMC8056755 DOI: 10.1083/jcb.201907183] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 12/29/2020] [Accepted: 02/09/2021] [Indexed: 12/20/2022] Open
Abstract
Lipid droplets (LDs) are critical for lipid storage and energy metabolism. LDs form in the endoplasmic reticulum (ER). However, the molecular basis for LD biogenesis remains elusive. Here, we show that fat storage–inducing transmembrane protein 2 (FIT2) interacts with ER tubule-forming proteins Rtn4 and REEP5. The association is mainly transmembrane domain based and stimulated by oleic acid. Depletion of ER tubule-forming proteins decreases the number and size of LDs in cells and Caenorhabditis elegans, mimicking loss of FIT2. Through cytosolic loops, FIT2 binds to cytoskeletal protein septin 7, an interaction that is also required for normal LD biogenesis. Depletion of ER tubule-forming proteins or septins delays nascent LD formation. In addition, FIT2-interacting proteins are up-regulated during adipocyte differentiation, and ER tubule-forming proteins, septin 7, and FIT2 are transiently enriched at LD formation sites. Thus, FIT2-mediated nascent LD biogenesis is facilitated by ER tubule-forming proteins and septins.
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Affiliation(s)
- Fang Chen
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Bing Yan
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jie Ren
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Rui Lyu
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yanfang Wu
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yuting Guo
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Dong Li
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Hong Zhang
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Junjie Hu
- National Laboratory of Biomacromolecules, Chinese Academy of Sciences Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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15
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Chen J, Wang X, Wang X, Li W, Shang C, Chen T, Chen Y. A FITM1-Related Methylation Signature Predicts the Prognosis of Patients With Non-Viral Hepatocellular Carcinoma. Front Genet 2020; 11:99. [PMID: 32174969 PMCID: PMC7056874 DOI: 10.3389/fgene.2020.00099] [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: 10/05/2019] [Accepted: 01/29/2020] [Indexed: 12/11/2022] Open
Abstract
Although great progress has been made in treatment against hepatitis virus infection, the prognosis of hepatocellular carcinoma (HCC) remains unsatisfied. Therefore, there is an unmet need to explore biomarkers or prognostic models for monitoring non-viral hepatocellular carcinoma. Accumulating evidence indicates that DNA methylation participates in carcinogenesis of malignancies. In the present study, we analyzed 101 non-viral HCC patients from TCGA database to figure out methylation-driven genes (MDGs) that might get involved in non-viral HCC pathogenesis using MethyMix algorithm. Then we picked out 8 key genes out of 137 MDGs that could affect the overall survival (OS) of both methylation and expression level. Using PCA, Uni-variate, Multi-variate, and LASSO cox regression analyses, we confirmed the potential prognostic value of these eight epigenetic genes. Ultimately, combined with immunohistochemistry (IHC), ROC, OS, and GSEA analyses, fat storage-inducing transmembrane protein1 (FITM1) was identified as a novel tumor suppressor gene in non-viral HCC and an applicable FITM1-methylation-based signature was built in a training set and validated in a testing set. Briefly, our work provides several potential biomarkers, especially FITM1, as well as a new method for disease surveillance and treatment strategy development.
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Affiliation(s)
- Jie Chen
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xicheng Wang
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xining Wang
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Wenxin Li
- Department of Cardiology, The Eight Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Changzhen Shang
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Tao Chen
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yajin Chen
- Department of Hepatobiliary Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
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16
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Hodson L, Gunn PJ. The regulation of hepatic fatty acid synthesis and partitioning: the effect of nutritional state. Nat Rev Endocrinol 2019; 15:689-700. [PMID: 31554932 DOI: 10.1038/s41574-019-0256-9] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is an increasing global public health burden. NAFLD is strongly associated with type 2 diabetes mellitus, obesity and cardiovascular disease and begins with intrahepatic triacylglycerol accumulation. Under healthy conditions, the liver regulates lipid metabolism to meet systemic energy needs in the fed and fasted states. The processes of fatty acid uptake, fatty acid synthesis and the intracellular partitioning of fatty acids into storage, oxidation and secretion pathways are tightly regulated. When one or more of these processes becomes dysregulated, excess lipid accumulation can occur. Although genetic and environmental factors have been implicated in the development of NAFLD, it remains unclear why an imbalance in these pathways begins. The regulation of fatty acid partitioning occurs at several points, including during triacylglycerol synthesis, lipid droplet formation and lipolysis. These processes are influenced by enzyme function, intake of dietary fats and sugars and whole-body metabolism, and are further affected by the presence of obesity or insulin resistance. Insight into how the liver controls fatty acid metabolism in health and how these processes might be affected in disease would offer the potential for new therapeutic treatments for NAFLD to be developed.
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Affiliation(s)
- Leanne Hodson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Headington, Oxford, UK.
- Oxford NIHR Biomedical Research Centre, Churchill Hospital, Headington, Oxford, UK.
| | - Pippa J Gunn
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine, University of Oxford, Headington, Oxford, UK
- Oxford NIHR Biomedical Research Centre, Churchill Hospital, Headington, Oxford, UK
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17
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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: 1.4] [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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18
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Breher-Esch S, Sahini N, Trincone A, Wallstab C, Borlak J. Genomics of lipid-laden human hepatocyte cultures enables drug target screening for the treatment of non-alcoholic fatty liver disease. BMC Med Genomics 2018; 11:111. [PMID: 30547786 PMCID: PMC6295111 DOI: 10.1186/s12920-018-0438-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 11/23/2018] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is a major health burden in need for new medication. To identify potential drug targets a genomic study was performed in lipid-laden primary human hepatocyte (PHH) and human hepatoma cell cultures. METHODS PHH, HuH7 and HepG2 hepatoma cell cultures were treated with lipids and/or TNFα. Intracellular lipid load was quantified with the ORO assay. The Affymetrix HG-U133+ array system was employed to perform transcriptome analysis. The lipid droplet (LD) growth and fusion was determined by fluorescence microscopy. LD associated proteins were imaged by confocal immunofluorescence microscopy and confirmed by Western immunoblotting. Bioinformatics defined perturbed metabolic pathways. RESULTS Whole genome expression profiling identified 227, 1031 and 571 significant regulated genes. Likewise, the combined lipid and TNFα treatment of PHH, HuH7 and HepG2 cell cultures revealed 154, 1238 and 278 differentially expressed genes. Although genomic responses differed among in-vitro systems, commonalities were ascertained by filtering the data for LD associated gene regulations. Among others the LD-growth and fusion associated cell death inducing DFFA like effector C (CIDEC), perilipins (PLIN2, PLIN3), the synaptosome-associated-protein 23 and the vesicle associated membrane protein 3 were strongly up-regulated. Likewise, the PPAR targets pyruvate-dehydrogenase-kinase-4 and angiopoietin-like-4 were up-regulated as was hypoxia-inducible lipid droplet-associated (HILPDA), flotilin and FGF21. Their inhibition ameliorates triglyceride and cholesterol accumulation. TNFα treatment elicited strong induction of the chemokine CXCL8, the kinases MAP3K8, MAP4K4 and negative regulators of cytokine signaling, i.e. SOCS2&SOCS3. Live cell imaging of DsRED calreticulin plasmid transfected HuH7 cells permitted an assessment of LD growth and fusion and confocal immunofluorescence microscopy evidenced induced LD-associated PLIN2, CIDEC, HIF1α, HILPDA, JAK1, PDK4 and ROCK2 expression. Notwithstanding, CPT1A protein was repressed to protect mitochondria from lipid overload. Pharmacological inhibition of the GTPase-dynamin and the fatty acid transporter-2 reduced lipid uptake by 28.5 and 35%, respectively. Finally, a comparisons of in-vitro/NAFLD patient biopsy findings confirmed common gene regulations thus demonstrating clinical relevance. CONCLUSION The genomics of fat-laden hepatocytes revealed LD-associated gene regulations and perturbed metabolic pathways. Immunofluorescence microscopy confirmed expression of coded proteins to provide a rationale for therapeutic intervention strategies. Collectively, the in-vitro system permits testing of drug candidates.
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Affiliation(s)
- Stephanie Breher-Esch
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Nishika Sahini
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Anna Trincone
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Christin Wallstab
- Institute of Biochemistry, Charité - University Medicine Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Jürgen Borlak
- Centre for Pharmacology and Toxicology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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19
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Dual extraction of mRNA and lipids from a single biological sample. Sci Rep 2018; 8:7019. [PMID: 29728575 PMCID: PMC5935724 DOI: 10.1038/s41598-018-25332-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 04/19/2018] [Indexed: 12/11/2022] Open
Abstract
The extraction of RNA and lipids from a large number of biological samples is time-consuming and costly with steps required for both transcriptomic and lipidomic approaches. Most protocols rely on independent extraction of nucleic acids and lipids from a single sample, thereby increasing the need for biological material and inducing variability in data analysis. We investigated whether it is possible to use a standard RNA extraction procedure to analyze not only RNA levels, but also lipids in a single liver sample. We show that the organic phase obtained when using standard reagents for RNA extraction can be used to analyze lipids, including neutral lipids and fatty acids, by gas chromatography. We applied this technique to an analysis of lipids and the associated gene expression pattern in mice with hepatic steatosis induced by pharmacological activation of nuclear receptor LXR.
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Miranda DA, Krause WC, Cazenave-Gassiot A, Suzawa M, Escusa H, Foo JC, Shihadih DS, Stahl A, Fitch M, Nyangau E, Hellerstein M, Wenk MR, Silver DL, Ingraham HA. LRH-1 regulates hepatic lipid homeostasis and maintains arachidonoyl phospholipid pools critical for phospholipid diversity. JCI Insight 2018. [PMID: 29515023 DOI: 10.1172/jci.insight.96151] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Excess lipid accumulation is an early signature of nonalcoholic fatty liver disease (NAFLD). Although liver receptor homolog 1 (LRH-1) (encoded by NR5A2) is suppressed in human NAFLD, evidence linking this phospholipid-bound nuclear receptor to hepatic lipid metabolism is lacking. Here, we report an essential role for LRH-1 in hepatic lipid storage and phospholipid composition based on an acute hepatic KO of LRH-1 in adult mice (LRH-1AAV8-Cre mice). Indeed, LRH-1-deficient hepatocytes exhibited large cytosolic lipid droplets and increased triglycerides (TGs). LRH-1-deficient mice fed high-fat diet displayed macrovesicular steatosis, liver injury, and glucose intolerance, all of which were reversed or improved by expressing wild-type human LRH-1. While hepatic lipid synthesis decreased and lipid export remained unchanged in mutants, elevated circulating free fatty acid helped explain the lipid imbalance in LRH-1AAV8-Cre mice. Lipidomic and genomic analyses revealed that loss of LRH-1 disrupts hepatic phospholipid composition, leading to lowered arachidonoyl (AA) phospholipids due to repression of Elovl5 and Fads2, two critical genes in AA biosynthesis. Our findings reveal a role for the phospholipid sensor LRH-1 in maintaining adequate pools of hepatic AA phospholipids, further supporting the idea that phospholipid diversity is an important contributor to healthy hepatic lipid storage.
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Affiliation(s)
- Diego A Miranda
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - William C Krause
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Amaury Cazenave-Gassiot
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Miyuki Suzawa
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Hazel Escusa
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Juat Chin Foo
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Diyala S Shihadih
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Andreas Stahl
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Mark Fitch
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Edna Nyangau
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Marc Hellerstein
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Markus R Wenk
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - David L Silver
- Signature Research Program in Cardiovascular and Metabolic Diseases, Duke-National University of Singapore, Singapore
| | - Holly A Ingraham
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
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21
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Abstract
Triglyceride molecules represent the major form of storage and transport of fatty acids within cells and in the plasma. The liver is the central organ for fatty acid metabolism. Fatty acids accrue in liver by hepatocellular uptake from the plasma and by de novo biosynthesis. Fatty acids are eliminated by oxidation within the cell or by secretion into the plasma within triglyceride-rich very low-density lipoproteins. Notwithstanding high fluxes through these pathways, under normal circumstances the liver stores only small amounts of fatty acids as triglycerides. In the setting of overnutrition and obesity, hepatic fatty acid metabolism is altered, commonly leading to the accumulation of triglycerides within hepatocytes, and to a clinical condition known as nonalcoholic fatty liver disease (NAFLD). In this review, we describe the current understanding of fatty acid and triglyceride metabolism in the liver and its regulation in health and disease, identifying potential directions for future research. Advances in understanding the molecular mechanisms underlying the hepatic fat accumulation are critical to the development of targeted therapies for NAFLD. © 2018 American Physiological Society. Compr Physiol 8:1-22, 2018.
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Affiliation(s)
- Michele Alves-Bezerra
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
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22
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Clinicoplacental correlates of amniocyte vacuolization in association with gastroschisis. Placenta 2017; 57:87-93. [DOI: 10.1016/j.placenta.2017.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/15/2017] [Accepted: 06/04/2017] [Indexed: 12/30/2022]
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23
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Kimmel AR, Sztalryd C. The Perilipins: Major Cytosolic Lipid Droplet-Associated Proteins and Their Roles in Cellular Lipid Storage, Mobilization, and Systemic Homeostasis. Annu Rev Nutr 2017; 36:471-509. [PMID: 27431369 DOI: 10.1146/annurev-nutr-071813-105410] [Citation(s) in RCA: 168] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The discovery by Dr. Constantine Londos of perilipin 1, the major scaffold protein at the surface of cytosolic lipid droplets in adipocytes, marked a fundamental conceptual change in the understanding of lipolytic regulation. Focus then shifted from the enzymatic activation of lipases to substrate accessibility, mediated by perilipin-dependent protein sequestration and recruitment. Consequently, the lipid droplet became recognized as a unique, metabolically active cellular organelle and its surface as the active site for novel protein-protein interactions. A new area of investigation emerged, centered on lipid droplets' biology and their role in energy homeostasis. The perilipin family is of ancient origin and has expanded to include five mammalian genes and a growing list of evolutionarily conserved members. Universally, the perilipins modulate cellular lipid storage. This review provides a summary that connects the perilipins to both cellular and whole-body homeostasis.
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Affiliation(s)
- Alan R Kimmel
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases, The National Institutes of Health, Bethesda, Maryland 20892;
| | - Carole Sztalryd
- The Geriatric Research Education and Clinical Center, Baltimore Veterans Affairs Medical Center, Baltimore, Maryland 21201.,Division of Endocrinology, Department of Medicine, School of Medicine, University of Maryland, Baltimore, Maryland 21201;
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24
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Lede V, Meusel A, Garten A, Popkova Y, Penke M, Franke C, Ricken A, Schulz A, Kiess W, Huster D, Schöneberg T, Schiller J. Altered hepatic lipid metabolism in mice lacking both the melanocortin type 4 receptor and low density lipoprotein receptor. PLoS One 2017; 12:e0172000. [PMID: 28207798 PMCID: PMC5313158 DOI: 10.1371/journal.pone.0172000] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 01/30/2017] [Indexed: 01/01/2023] Open
Abstract
Obesity is often associated with dyslipidemia and hepatosteatosis. A number of animal models of non-alcoholic fatty liver disease (NAFLD) are established but they significantly differ in the molecular and biochemical changes depending on the genetic modification and diet used. Mice deficient for melanocortin type 4 receptor (Mc4rmut) develop hyperphagia, obesity, and subsequently NAFLD already under regular chow and resemble more closely the energy supply-driven obesity found in humans. This animal model was used to assess the molecular and biochemical consequences of hyperphagia-induced obesity on hepatic lipid metabolism. We analyzed transcriptome changes in Mc4rmut mice by RNA sequencing and used high resolution 1H magic angle spinning NMR spectroscopy and MALDI-TOF mass spectrometry to assess changes in the lipid composition. On the transcriptomic level we found significant changes in components of the triacylglycerol metabolism, unsaturated fatty acids biosynthesis, peroxisome proliferator-activated receptor signaling pathways, and lipid transport and storage compared to the wild-type. These findings were supported by increases in triacylglycerol, monounsaturated fatty acid, and arachidonic acid levels. The transcriptome signatures significantly differ from those of other NAFLD mouse models supporting the concept of hepatic subphenotypes depending on the genetic background and diet. Comparative analyses of our data with previous studies allowed for the identification of common changes and genotype-specific components and pathways involved in obesity-associated NAFLD.
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MESH Headings
- Animals
- Diet, High-Fat/adverse effects
- Disease Models, Animal
- Female
- Gene Expression Profiling
- High-Throughput Nucleotide Sequencing
- Hypercholesterolemia/etiology
- Hypercholesterolemia/metabolism
- Hypercholesterolemia/pathology
- Lipid Metabolism
- Lipogenesis/genetics
- Liver/metabolism
- Liver/pathology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mutation/genetics
- Non-alcoholic Fatty Liver Disease/etiology
- Non-alcoholic Fatty Liver Disease/metabolism
- Non-alcoholic Fatty Liver Disease/pathology
- Obesity/complications
- Receptor, Melanocortin, Type 4/deficiency
- Receptor, Melanocortin, Type 4/genetics
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
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Affiliation(s)
- Vera Lede
- Molecular Biochemistry, Rudolf-Schönheimer-Institute of Biochemistry, University of Leipzig, Leipzig, Germany
| | - Andrej Meusel
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Antje Garten
- Hospital for Children & Adolescents, Department of Women and Child Health, Center for Pediatric Research Leipzig, University of Leipzig, Leipzig, Germany
| | - Yulia Popkova
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Melanie Penke
- Hospital for Children & Adolescents, Department of Women and Child Health, Center for Pediatric Research Leipzig, University of Leipzig, Leipzig, Germany
| | | | - Albert Ricken
- Institute of Anatomy, Medical Faculty, University of Leipzig, Leipzig, Germany
| | - Angela Schulz
- Molecular Biochemistry, Rudolf-Schönheimer-Institute of Biochemistry, University of Leipzig, Leipzig, Germany
| | - Wieland Kiess
- Hospital for Children & Adolescents, Department of Women and Child Health, Center for Pediatric Research Leipzig, University of Leipzig, Leipzig, Germany
| | - Daniel Huster
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
| | - Torsten Schöneberg
- Molecular Biochemistry, Rudolf-Schönheimer-Institute of Biochemistry, University of Leipzig, Leipzig, Germany
- * E-mail: (JS); (TS)
| | - Jürgen Schiller
- Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
- * E-mail: (JS); (TS)
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25
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Wang Y, Liu L, Zhang H, Fan J, Zhang F, Yu M, Shi L, Yang L, Lam SM, Wang H, Chen X, Wang Y, Gao F, Shui G, Xu Z. Mea6 controls VLDL transport through the coordinated regulation of COPII assembly. Cell Res 2016; 26:787-804. [PMID: 27311593 DOI: 10.1038/cr.2016.75] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/02/2016] [Accepted: 05/09/2016] [Indexed: 12/16/2022] Open
Abstract
Lipid accumulation, which may be caused by the disturbance in very low density lipoprotein (VLDL) secretion in the liver, can lead to fatty liver disease. VLDL is synthesized in endoplasmic reticulum (ER) and transported to Golgi apparatus for secretion into plasma. However, the underlying molecular mechanism for VLDL transport is still poorly understood. Here we show that hepatocyte-specific deletion of meningioma-expressed antigen 6 (Mea6)/cutaneous T cell lymphoma-associated antigen 5C (cTAGE5C) leads to severe fatty liver and hypolipemia in mice. Quantitative lipidomic and proteomic analyses indicate that Mea6/cTAGE5 deletion impairs the secretion of different types of lipids and proteins, including VLDL, from the liver. Moreover, we demonstrate that Mea6/cTAGE5 interacts with components of the ER coat protein complex II (COPII) which, when depleted, also cause lipid accumulation in hepatocytes. Our findings not only reveal several novel factors that regulate lipid transport, but also provide evidence that Mea6 plays a critical role in lipid transportation through the coordinated regulation of the COPII machinery.
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Affiliation(s)
- Yaqing Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Liang Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100101, China
| | - Hongsheng Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100101, China
| | - Junwan Fan
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100101, China
| | - Feng Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100101, China
| | - Mei Yu
- School of Life Science, Shandong University, Jinan 250100, China
| | - Lei Shi
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lin Yang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sin Man Lam
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Huimin Wang
- Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Xiaowei Chen
- Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Yingchun Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fei Gao
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhiheng Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.,Translational Medical Center for Stem Cell Therapy, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China
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26
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Zhu R, Baker SS, Moylan CA, Abdelmalek MF, Guy CD, Zamboni F, Wu D, Lin W, Liu W, Baker RD, Govindarajan S, Cao Z, Farci P, Diehl AM, Zhu L. Systematic transcriptome analysis reveals elevated expression of alcohol-metabolizing genes in NAFLD livers. J Pathol 2016; 238:531-542. [DOI: 10.1002/path.4650] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Ruixin Zhu
- Department of Bioinformatics; Tongji University; Shanghai China
| | - Susan S Baker
- Digestive Diseases and Nutrition Center, Department of Pediatrics; The State University of New York at Buffalo; Buffalo New York USA
| | - Cynthia A Moylan
- Division of Gastroenterology and Hepatology, Department of Medicine; Duke University; Durham North Carolina USA
- Division of Gastroenterology and Hepatology, Department of Medicine; Durham Veterans Affairs Medical Center; Durham North Carolina USA
| | - Manal F Abdelmalek
- Division of Gastroenterology and Hepatology, Department of Medicine; Duke University; Durham North Carolina USA
| | - Cynthia D Guy
- Department of Pathology; Duke University; Durham North Carolina USA
| | - Fausto Zamboni
- Liver Transplantation Center; Brotzu Hospital; 09134 Cagliari Italy
| | - Dingfeng Wu
- Department of Bioinformatics; Tongji University; Shanghai China
| | - Weili Lin
- Department of Bioinformatics; Tongji University; Shanghai China
| | - Wensheng Liu
- Digestive Diseases and Nutrition Center, Department of Pediatrics; The State University of New York at Buffalo; Buffalo New York USA
| | - Robert D Baker
- Digestive Diseases and Nutrition Center, Department of Pediatrics; The State University of New York at Buffalo; Buffalo New York USA
| | - Sugantha Govindarajan
- Department of Pathology; University of Southern California; Los Angeles California USA
| | - Zhiwei Cao
- Department of Bioinformatics; Tongji University; Shanghai China
| | - Patrizia Farci
- Laboratory of Infectious Diseases; National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda Maryland USA
| | - Anna Mae Diehl
- Division of Gastroenterology and Hepatology, Department of Medicine; Duke University; Durham North Carolina USA
| | - Lixin Zhu
- Digestive Diseases and Nutrition Center, Department of Pediatrics; The State University of New York at Buffalo; Buffalo New York USA
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27
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Choudhary V, Ojha N, Golden A, Prinz WA. A conserved family of proteins facilitates nascent lipid droplet budding from the ER. J Cell Biol 2016; 211:261-71. [PMID: 26504167 PMCID: PMC4621845 DOI: 10.1083/jcb.201505067] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Visualization of nascent lipid droplets reveals that they form lens-like structures inside the ER membrane bilayer and that FIT proteins are necessary for lipid droplet protrusion toward the cytoplasm. Lipid droplets (LDs) are found in all cells and play critical roles in lipid metabolism. De novo LD biogenesis occurs in the endoplasmic reticulum (ER) but is not well understood. We imaged early stages of LD biogenesis using electron microscopy and found that nascent LDs form lens-like structures that are in the ER membrane, raising the question of how these nascent LDs bud from the ER as they grow. We found that a conserved family of proteins, fat storage-inducing transmembrane (FIT) proteins, is required for proper budding of LDs from the ER. Elimination or reduction of FIT proteins in yeast and higher eukaryotes causes LDs to remain in the ER membrane. Deletion of the single FIT protein in Caenorhabditis elegans is lethal, suggesting that LD budding is an essential process in this organism. Our findings indicated that FIT proteins are necessary to promote budding of nascent LDs from the ER.
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Affiliation(s)
- Vineet Choudhary
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Namrata Ojha
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Andy Golden
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - William A Prinz
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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28
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In Situ Evaluation of Oxidative Stress in Rat Fatty Liver Induced by a Methionine- and Choline-Deficient Diet. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:9307064. [PMID: 26881047 PMCID: PMC4736780 DOI: 10.1155/2016/9307064] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 11/01/2015] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a serious health problem in developed countries. We documented the effects of feeding with a NAFLD-inducing, methionine- and choline-deficient (MCD) diet, for 1-4 weeks on rat liver oxidative stress, with respect to a control diet. Glycogen, neutral lipids, ROS, peroxidated proteins, and SOD2 were investigated using histochemical procedures; ATP, GSH, and TBARS concentrations were investigated by biochemical dosages, and SOD2 expression was investigated by Western Blotting. In the 4-week-diet period, glycogen stores decreased whereas lipid droplets, ROS, and peroxidated proteins expression (especially around lipid droplets of hepatocytes) increased. SOD2 immunostaining decreased in poorly steatotic hepatocytes but increased in the thin cytoplasm of macrosteatotic cells; a trend towards a quantitative decrease of SOD expression in homogenates occurred after 3 weeks. ATP and GSH values were significantly lower for rats fed with the MCD diet with respect to the controls. An increase of TBARS in the last period of the diet is in keeping with the high ROS production and low antioxidant defense; these TBARS may promote protein peroxidation around lipid droplets. Since these proteins play key roles in lipid mobilization, storage, and metabolism, this last information appears significant, as it points towards a previously misconsidered target of NAFLD-associated oxidative stress that might be responsible for lipid dysfunction.
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29
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Soni NK, Nookaew I, Sandberg AS, Gabrielsson BG. Eicosapentaenoic and docosahexaenoic acid-enriched high fat diet delays the development of fatty liver in mice. Lipids Health Dis 2015; 14:74. [PMID: 26193881 PMCID: PMC4509768 DOI: 10.1186/s12944-015-0072-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/01/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Low hepatic content of n-3 PUFA has been associated with NAFLD in humans. Whether this is associated with reduced dietary intake or increased turnover of these FA is not clear. We have here investigated the effects of dietary fat quality on hepatic lipid storage and transcriptomics over time. AIM To investigate the effects of quality of fat in a high fat diet (HFD) over time on hepatic lipid storage and liver transcriptomics. METHODS AND RESULTS Male C57BL/6J mice were fed control, HFD-eicosapentaenoic acid (EPA)/ docosahexaenoic acid (DHA) or HFD-corn oil diet for 8 or 12 weeks. Body weight, body composition, plasma and hepatic triglyceride contents were measured. Hepatic transcriptomes were analysed by microarray followed by gene-set enrichment analyses. At 8 weeks, the HFD-corn oil mice had higher body weight and adipose depot mass than the HFD-EPA/DHA but there were no differences at 12 weeks. Hepatic triglyceride content was lower in HFD-EPA/DHA fed compared with the HFD-corn oil fed mice at both time-points. Enrichment analyses of the hepatic transcriptomes showed that lipid/fatty acid biosynthesis; transport and homeostasis were lower in the HFD-EPA/DHA fed compared with the HFD-corn oil fed mice. Genes encoding proteins associated to cytoplasmic lipid droplets were expressed at higher levels in livers from the HFD-corn oil compared to HFD-EPA/DHA mice. CONCLUSIONS Dietary EPA and DHA counteracted development of HFD-induced fatty liver. The liver transcriptome data implicate that the quality of dietary fat could modulate Ppar-related gene expression that in turn affects hepatic lipid storage and maintenance of metabolic health.
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Affiliation(s)
- Nikul K Soni
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
| | - Intawat Nookaew
- The division of Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden. .,Present address: Comparative Genomics Group, Biosciences division, Oak Ridge National Library, Oak Ridge, TN, 37831, USA.
| | - Ann-Sofie Sandberg
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
| | - Britt G Gabrielsson
- Divisions of Food and Nutrition Science, Department of Biology and Biological Engineering, Chalmers University of Technology, SE-41296, Gothenburg, Sweden.
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30
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Liu J, Ma KL, Zhang Y, Wu Y, Hu ZB, Lv LL, Tang RN, Liu H, Ruan XZ, Liu BC. Activation of mTORC1 disrupted LDL receptor pathway: a potential new mechanism for the progression of non-alcoholic fatty liver disease. Int J Biochem Cell Biol 2015; 61:8-19. [PMID: 25622557 DOI: 10.1016/j.biocel.2015.01.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Revised: 12/22/2014] [Accepted: 01/16/2015] [Indexed: 10/24/2022]
Abstract
Our previous studies demonstrated that inflammation exacerbates the progression of non-alcoholic fatty liver disease (NAFLD) by disrupting cholesterol homeostasis. This study aimed to investigate the role of mammalian target of rapamycin complex 1 (mTORC1) in NAFLD under conditions of inflammation. Chronic inflammation was induced by using subcutaneous injections of 10% casein in apolipoprotein E knockout (ApoE KO) mice in vivo and interleukin-1β stimulation of the HepG2 hepatoblastoma cell line in vitro. Results demonstrated that inflammation increased lipid accumulation in HepG2 cells and in livers of apolipoprotein E knockout mice. These effects were correlated with an increase in low density lipoprotein receptor (LDLR) gene transcription, which was mediated through the up-regulation of sterol regulatory element-binding protein (SREBP) cleavage-activating protein (SCAP), SREBP-2, and through enhanced translocation of the SCAP/SREBP-2 complex from endoplasmic reticulum (ER) to Golgi. In addition, our data indicated that inflammation down-regulated the expression of proprotein convertase subtilisin kexin 9 (PCSK9) and prevented the degradation of LDLR protein via posttranscriptional mechanisms. Further analysis showed that inflammation increased the protein phosphorylation of mTOR, eukaryotic initiation factor 4E-binding protein 1, and p70 S6 kinase. Interestingly, blocking mTORC1 activity inhibited the translocation of SCAP/SREBP-2 complex from the ER to the Golgi and decreased the expression of LDLR, SCAP, and SREBP-2. These effects were accompanied by an increase in the expression of PCSK9 and accelerated LDLR degradation. Our findings demonstrated that increased mTORC1 activity exacerbated the progression of NAFLD by disrupting LDLR expression via transcriptional and posttranscriptional mechanisms.
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Affiliation(s)
- Jing Liu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Kun Ling Ma
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China.
| | - Yang Zhang
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Yu Wu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Ze Bo Hu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Lin Li Lv
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Ri Ning Tang
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Hong Liu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
| | - Xiong Zhong Ruan
- Centre for Nephrology, University College London (UCL) Medical School, Royal Free Campus, UK
| | - Bi Cheng Liu
- Institute of Nephrology, Zhong Da Hospital, Southeast University School of Medicine, Nanjing City, Jiangsu Province, China
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31
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Tzeng TF, Liou SS, Liu IM. 6-Gingerol mitigates nutritional steatohepatitis through regulating key genes related to oxidative stress, inflammation and fibrogenesis. RSC Adv 2014. [DOI: 10.1039/c4ra12030b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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32
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Asimakopoulou A, Borkham-Kamphorst E, Henning M, Yagmur E, Gassler N, Liedtke C, Berger T, Mak TW, Weiskirchen R. Lipocalin-2 (LCN2) regulates PLIN5 expression and intracellular lipid droplet formation in the liver. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1842:1513-24. [PMID: 25086218 DOI: 10.1016/j.bbalip.2014.07.017] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 07/17/2014] [Accepted: 07/22/2014] [Indexed: 01/14/2023]
Abstract
Lipocalin-2 (LCN2) belongs to the superfamily of lipocalins and plays critical roles in the control of cellular homeostasis during inflammation and in responses to cellular stress or injury. In the liver, LCN2 triggers protective effects following acute or chronic injury, and its expression is a reliable indicator of liver damage. However, little is known about LCN2's functions in the homeostasis and metabolism of hepatic lipids or in the development of steatosis. In this study, we fed wild type (WT) and LCN2-deficient (Lcn2(-/-)) mice a methionine- and choline-deficient (MCD) diet as a nutritional model of non-alcoholic steatohepatitis, and compared intrahepatic lipid accumulation, lipid droplet formation, mitochondrial content, and expression of the Perilipin proteins that regulate cellular lipid metabolism. We found that Lcn2(-/-) mice fed an MCD diet accumulated more lipids in the liver than WT controls, and that the basal expression of the lipid droplet coat protein Perilipin 5 (PLIN5, also known as OXPAT) was significantly reduced in these animals. Similarly, the overexpression of LCN2 and PLIN5 were also found in animals that were fed with a high fat diet. Furthermore, the loss of LCN2 and/or PLIN5 in hepatocytes prevented normal intracellular lipid droplet formation both in vitro and in vivo. Restoration of LCN2 in Lcn2(-/-) primary hepatocytes by either transfection or adenoviral vector infection induced PLIN5 expression and restored proper lipid droplet formation. Our data indicate that LCN2 is a key modulator of hepatic lipid homeostasis that controls the formation of intracellular lipid droplets by regulating PLIN5 expression. LCN2 may therefore represent a novel therapeutic drug target for the treatment of liver diseases associated with elevated fat accumulation and steatosis.
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Affiliation(s)
- Anastasia Asimakopoulou
- Institute of Clinical Chemistry and Pathobiochemistry, RWTH University Hospital Aachen, Aachen, Germany
| | - Erawan Borkham-Kamphorst
- Institute of Clinical Chemistry and Pathobiochemistry, RWTH University Hospital Aachen, Aachen, Germany
| | - Marc Henning
- Institute of Clinical Chemistry and Pathobiochemistry, RWTH University Hospital Aachen, Aachen, Germany
| | - Eray Yagmur
- MVZ Medical Laboratory Center, Dr. Stein and Partner, Mönchengladbach, Germany
| | - Nikolaus Gassler
- Institute of Pathology, RWTH University Hospital Aachen, Aachen, Germany
| | - Christian Liedtke
- Department of Internal Medicine III, RWTH University Hospital Aachen, Aachen, Germany
| | - Thorsten Berger
- The Campbell Family Institute for Breast Cancer Research, University Health Network, Toronto, ON, Canada
| | - Tak W Mak
- The Campbell Family Institute for Breast Cancer Research, University Health Network, Toronto, ON, Canada; Ontario Cancer Institute, University Health Network, Toronto, ON, Canada
| | - Ralf Weiskirchen
- Institute of Clinical Chemistry and Pathobiochemistry, RWTH University Hospital Aachen, Aachen, Germany.
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33
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Abstract
Cardiovascular disease represents the most common cause of death in patients with nonalcoholic fatty liver disease (NAFLD). Patients with NAFLD exhibit an atherogenic dyslipidemia that is characterized by an increased plasma concentration of triglycerides, reduced concentration of high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) particles that are smaller and more dense than normal. The pathogenesis of NAFLD-associated atherogenic dyslipidemia is multifaceted, but many aspects are attributable to manifestations of insulin resistance. Here the authors review the structure, function, and metabolism of lipoproteins, which are macromolecular particles of lipids and proteins that transport otherwise insoluble triglyceride and cholesterol molecules within the plasma. They provide a current explanation of the metabolic perturbations that are observed in the setting of insulin resistance. An improved understanding of the pathophysiology of atherogenic dyslipidemia would be expected to guide therapies aimed at reducing morbidity and mortality in patients with NAFLD.
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Affiliation(s)
- Edward Fisher
- Division of Cardiology, Department of Medicine, The Marc and Ruti Bell Program in Vascular Biology, New York University School of Medicine, New York, New York
| | - David Cohen
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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