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Zhang RN, Pan Q, Zheng RD, Mi YQ, Shen F, Zhou D, Chen GY, Zhu CY, Fan JG. Genome-wide analysis of DNA methylation in human peripheral leukocytes identifies potential biomarkers of nonalcoholic fatty liver disease. Int J Mol Med 2018; 42:443-452. [PMID: 29568887 DOI: 10.3892/ijmm.2018.3583] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 02/12/2018] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to uncover the role of leukocytic DNA methylation in the evaluation of nonalcoholic fatty liver disease (NAFLD). Patients with biopsy-proven NAFLD (n=35) and normal controls (n=30) were recruited from Chinese Han population. Their DNA methylation in peripheral leukocytes was subjected to genome-wide profiling. The association between differential methylation of CpG sites and NAFLD was further investigated on the basis of histopathological classification, bioinformatics, and pyrosequencing. A panel of 863 differentially methylated CpG sites dominated by global hypomethylation, characterized the NAFLD patients. Hypomethylated CpG sites of Acyl-CoA synthetase long-chain family member 4 (ACSL4) (cg15536552) and carnitine palmitoyltransferase 1C (CPT1C) (cg21604803) associated with the increased risk of NAFLD [cg15536552, odds ratio (OR): 11.44, 95% confidence interval (CI): 1.04‑125.37, P=0.046; cg21604803, OR: 6.57, 95% CI: 1.02-42.15, P=0.047] at cut-off β-values of <3.36 (ACSL4 cg15536552) and <3.54 (CPT1C cg21604803), respectively, after the adjustment of age, sex, body mass index (BMI) and homeostasis model assessment of insulin resistant (HOMA-IR). Their methylation levels also served as biomarkers of NAFLD (ACSL4 cg15536552, AUC: 0.80, 95% CI: 0.62-0.98, P=0.009; CPT1C cg21604803, AUC: 0.78, 95% CI: 0.65-0.91, P=0.001). Pathologically, lowered methylation level (β-values <3.26) of ACSL4 (cg15536552) conferred susceptibility to nonalcoholic steatohepatitis (NASH). Taken together, genome-wide hypomethylation of peripheral leukocytes may differentiate NAFLD patients from normal controls. The leukocytic hypomethylated ACSL4 (cg15536552) was suggested to be a biomarker for the pathological characteristics of NAFLD.
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Affiliation(s)
- Rui-Nan Zhang
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Qin Pan
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Rui-Dan Zheng
- Diagnosis and Treatment Center for Liver Diseases, Zhengxing Hospital, Zhangzhou, Fujian 363000, P.R. China
| | - Yu-Qiang Mi
- Department of Infective Diseases, Tianjin Infectious Disease Hospital, Tianjin 300192, P.R. China
| | - Feng Shen
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Da Zhou
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Guang-Yu Chen
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Chan-Yan Zhu
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
| | - Jian-Gao Fan
- Center for Fatty Liver, Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, P.R. China
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Lim HW, Bernstein DE. Risk Factors for the Development of Nonalcoholic Fatty Liver Disease/Nonalcoholic Steatohepatitis, Including Genetics. Clin Liver Dis 2018; 22:39-57. [PMID: 29128060 DOI: 10.1016/j.cld.2017.08.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nonalcoholic fatty liver disease is emerging as the most common cause of chronic liver disease worldwide. This trend is, in part, secondary, to the growing incidence of obesity, type 2 diabetes, and metabolic syndrome. Other risk factors include age, gender, race/ethnicity, genetic predisposition, and polycystic ovarian disease. With the introduction of genome-wide association studies, genetic mutations contributing to inherited susceptibility to steatosis have been identified, which hold keys to future improvement in diagnosis and management. This article expands on the aforementioned risk factors and summarizes the current available data on genetic and environmental factors associated with this common entity.
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Affiliation(s)
- Huei-Wen Lim
- Department of Internal Medicine, Northwell Health, 400 Community Drive, Manhasset, NY 11030, USA
| | - David E Bernstein
- Department of Gastroenterology and Hepatology, Northwell Health, Center for Liver Diseases, 400 Community Drive, Manhasset, NY 11030, USA.
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103
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Volpi-Lagreca G, Duckett SK. Supplementation of glycerol or fructose via drinking water to grazing lambs on tissue glycogen level and lipogenesis. J Anim Sci 2018; 95:2558-2575. [PMID: 28727036 DOI: 10.2527/jas.2017.1449] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Lambs ( = 18; 40.1 ± 7.4 kg BW) were used to assess supplementation of glycerol or fructose via drinking water on growth, tissue glycogen levels, postmortem glycolysis, and lipogenesis. Lambs were blocked by BW and allocated to alfalfa paddocks (2 lambs/paddock and 3 paddocks/treatment). Each paddock within a block was assigned randomly to drinking water treatments for 30 d: 1) control (CON), 2) 120 g fructose/L of drinking water (FRU), or 3) 120 g glycerol/L of drinking water (GLY). Lambs grazed alfalfa with free access to water treatments for 28 d and then were fasted in indoor pens for a final 2 d with access to only water treatments. Data were analyzed using the MIXED procedure of SAS with water treatment and time (when appropriate) in the model. During the 28-d grazing period, ADG was greater ( < 0.05) for GLY than for CON or FRU. During the 2-d fasting period, BW shrink was lower ( < 0.05) for GLY compared with CON or FRU. Hot carcass weight was greater ( < 0.05) for GLY than for FRU. The interaction for glycogen content × postmortem time was significant ( = 0.003) in LM and semitendinosus (ST) muscles. Glycogen content in the LM was greater ( < 0.05) for GLY at 2 and 3 h and for FRU at 1 h postmortem compared with CON. Glycogen content in ST did not differ between treatments ( > 0.05). Liver glycogen content was over 14-fold greater ( < 0.05) for GLY compared with FRU or CON. Liver free glucose was greater ( < 0.05) for GLY than for CON, whereas liver lipid content was higher ( < 0.05) for CON than for GLY. Supplementation with GLY increased ( < 0.05) odd-chain fatty acids in LM, subcutaneous fat (SQ), and the liver. Stearic acid (C18:0) concentrations were reduced in LM ( = 0.064) and subcutaneous adipose tissue (SQ; = 0.018), whereas oleic acid (C18:1 -9) concentration tended to be increased ( = 0.066) in SQ with FRU and GLY. Linolenic acid (C18:3 -3) was reduced ( = 0.031) and all long-chain -3 fatty acid (eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) concentrations were increased ( < 0.05) with FRU and GLY compared with CON. Glycerol supplementation upregulated ( < 0.05) stearoyl-CoA desaturate () and fatty acid synthase () mRNA by over 40-fold in the SQ and 5-fold in the liver. Glycerol supplementation also upregulated ( < 0.05) glucose transporters and glycogen branching enzyme in the liver. Overall, glycerol supplementation improved growth, reduced BW shrink during fasting, increased glycogen content in muscle and the liver, and stimulated de novo lipogenesis.
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104
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Chinese olive extract ameliorates hepatic lipid accumulation in vitro and in vivo by regulating lipid metabolism. Sci Rep 2018; 8:1057. [PMID: 29348600 PMCID: PMC5773498 DOI: 10.1038/s41598-018-19553-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/03/2018] [Indexed: 12/20/2022] Open
Abstract
Chinese olive contains plenty of polyphenols, which possess a wide range of biological actions. In this study, we aimed to investigate the role of the ethyl acetate fraction of Chinese olive fruit extract (CO-EtOAc) in the modulation of lipid accumulation in vitro and in vivo. In cellular studies, CO-EtOAc attenuated oleic acid-induced lipid accumulation; we then elucidated the molecular mechanisms of CO-EtOAc in FL83B mouse hepatocytes. CO-EtOAc suppressed the mRNA levels of fatty acid transporter genes (CD36 and FABP) and lipogenesis genes (SREBP-1c, FAS, and ACC1), but upregulated genes that govern lipolysis (HSL) and lipid oxidation (PPARα, CPT-1, and ACOX). Moreover, CO-EtOAc increased the protein expression of phosphorylated AMPK, ACC1, CPT-1, and PPARα, but downregulated the expression of mature SREBP-1c and FAS. AMPK plays an essential role in CO-EtOAc-mediated amelioration of lipid accumulation. Furthermore, we confirmed that CO-EtOAc significantly inhibited body weight gain, epididymal adipose tissue weight, and hepatic lipid accumulation via regulation of the expression of fatty acid transporter, lipogenesis, and fatty acid oxidation genes and proteins in C57BL/6 mice fed a 60% high-fat diet. Therefore, Chinese olive fruits may have the potential to improve the metabolic abnormalities associated with fatty liver under high fat challenge.
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105
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Rico J, Zang Y, Haughey N, Rius A, McFadden J. Short communication: Circulating fatty acylcarnitines are elevated in overweight periparturient dairy cows in association with sphingolipid biomarkers of insulin resistance. J Dairy Sci 2018; 101:812-819. [DOI: 10.3168/jds.2017-13171] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 09/16/2017] [Indexed: 12/19/2022]
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Litwak SA, Pang L, Galic S, Igoillo-Esteve M, Stanley WJ, Turatsinze JV, Loh K, Thomas HE, Sharma A, Trepo E, Moreno C, Gough DJ, Eizirik DL, de Haan JB, Gurzov EN. JNK Activation of BIM Promotes Hepatic Oxidative Stress, Steatosis, and Insulin Resistance in Obesity. Diabetes 2017; 66:2973-2986. [PMID: 28928277 DOI: 10.2337/db17-0348] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 09/13/2017] [Indexed: 11/13/2022]
Abstract
The members of the BCL-2 family are crucial regulators of the mitochondrial pathway of apoptosis in normal physiology and disease. Besides their role in cell death, BCL-2 proteins have been implicated in the regulation of mitochondrial oxidative phosphorylation and cellular metabolism. It remains unclear, however, whether these proteins have a physiological role in glucose homeostasis and metabolism in vivo. In this study, we report that fat accumulation in the liver increases c-Jun N-terminal kinase-dependent BCL-2 interacting mediator of cell death (BIM) expression in hepatocytes. To determine the consequences of hepatic BIM deficiency in diet-induced obesity, we generated liver-specific BIM-knockout (BLKO) mice. BLKO mice had lower hepatic lipid content, increased insulin signaling, and improved global glucose metabolism. Consistent with these findings, lipogenic and lipid uptake genes were downregulated and lipid oxidation enhanced in obese BLKO mice. Mechanistically, BIM deficiency improved mitochondrial function and decreased oxidative stress and oxidation of protein tyrosine phosphatases, and ameliorated activation of peroxisome proliferator-activated receptor γ/sterol regulatory element-binding protein 1/CD36 in hepatocytes from high fat-fed mice. Importantly, short-term knockdown of BIM rescued obese mice from insulin resistance, evidenced by reduced fat accumulation and improved insulin sensitivity. Our data indicate that BIM is an important regulator of liver dysfunction in obesity and a novel therapeutic target for restoring hepatocyte function.
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Affiliation(s)
- Sara A Litwak
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
| | - Lokman Pang
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | - Sandra Galic
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
| | | | - William J Stanley
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | | | - Kim Loh
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
| | - Helen E Thomas
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
| | - Arpeeta Sharma
- Oxidative Stress Laboratory, Basic Science Division, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Eric Trepo
- Clinique Universitaire de Bruxelles, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium
- Laboratory of Experimental Gastroenterology, Université Libre de Bruxelles, Brussels, Belgium
| | - Christophe Moreno
- Clinique Universitaire de Bruxelles, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium
- Laboratory of Experimental Gastroenterology, Université Libre de Bruxelles, Brussels, Belgium
| | - Daniel J Gough
- Hudson Institute of Medical Research, Clayton, Victoria, Australia
- Department of Molecular and Translational Science, Monash University, Clayton, Victoria, Australia
| | - Decio L Eizirik
- ULB Center for Diabetes Research, Université Libre de Bruxelles, Brussels, Belgium
| | - Judy B de Haan
- Oxidative Stress Laboratory, Basic Science Division, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Esteban N Gurzov
- St. Vincent's Institute of Medical Research, Melbourne, Victoria, Australia
- Department of Medicine, St. Vincent's Hospital, The University of Melbourne, Melbourne, Victoria, Australia
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107
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Kim SE, Lee JH, Kim TG, Kim YH, Chung KJ. Fat Graft Survival After Recipient Site Pretreatment With Fractional Carbon Dioxide Laser. Ann Plast Surg 2017; 79:552-557. [DOI: 10.1097/sap.0000000000001218] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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108
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Sun XJ, Xu GL. Overexpression of Acyl-CoA Ligase 4 (ACSL4) in Patients with Hepatocellular Carcinoma and its Prognosis. Med Sci Monit 2017; 23:4343-4350. [PMID: 28887439 PMCID: PMC5602145 DOI: 10.12659/msm.906639] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background Recently, accumulating studies have found that ACSL4 dysregulation is related to a great number of malignant tumors. The purpose of the present study was to explore the relationship between ACSL4 expression level and clinical prognosis of hepatocellular carcinoma (HCC) patients. Material/Methods The Oncomine and TCGA databases were used to predict the expression of ACSL4 mRNA in HCC and its association with HCC prognosis. Further, immunohistochemistry was performed to verify the ACSL4 protein expression in 116 paired HCC and adjacent normal tissues. Kaplan-Meier and cox analysis were performed to validate the correlation between ACSL4 expression and HCC prognosis. Results We first used the Oncomine database to find that ACSL4 mRNA expression level was significantly higher in HCC tissues than that in normal tissues (p all <0.001). The results were consistent with those in the TCGA database. Then, immunohistochemical results demonstrated that the ACSL4 positive expression rate was 70.7% in HCC tissues. ACSL4 differential expression level was significantly related to Edmondson grade (p=0.010), AFP (p=0.001) and TNM stage (p=0.012). Survival analysis revealed that both overall survival (OS) and disease-free survival (DFS) time were remarkably reduced in HCC patients with ACSL4 high expression (p=0.001 and 0.000, respectively). Moreover, Cox multivariate analysis demonstrated that ACSL4 expression was the only independent prognostic factor for both OS and DFS (both p values=0.001). Conclusions Taken together, our study demonstrated that ACSL4 was overexpressed in HCC, and it will be a new potential therapeutic target for HCC as an independent adverse prognostic parameter.
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Affiliation(s)
- Xiao-Jie Sun
- Medical College of Shandong University, Jinan, Shandong, China (mainland).,Department of Vascular Surgery, Anhui Provincial Hospital, Anhui Medical University, Hefei, Anhui, China (mainland)
| | - Ge-Liang Xu
- Department of Hepatic Surgery, Anhui Provincial Hospital, Anhui Medical University, Hefei, Anhui, China (mainland)
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Abstract
INTRODUCTION Various methods have been suggested to improve fat graft survival and decrease graft loss. The exact mechanism of fat graft survival is still unclear, and new strategies are needed to further investigate it. MATERIALS AND METHODS The efficacy of epineural sheath in fat volume maintenance was tested in rat model. Five experimental groups were created: group 1, fat graft without any coverage; group 2, epineural sheath tube alone; group 3, epineural sheath tube filled with fat graft; group 4, fat graft mixed with minced epineural sheath without any coverage; and group 5, fat graft covered with the epineural sheath patch. All grafts were implanted into the dorsal subcutaneous region and were followed for up to 12 weeks, when samples were harvested for hematoxylin and eosin and immunostaining for vascular endothelial growth factor expression and perilipin evaluation of fat viability. RESULTS In groups 1 and 4, over 25% of graft loss was observed at first week, over 50% at third week, and 100% at sixth week postimplantation. The weight of fat graft within the epineural sheath tube and the weight of epineural tube (ET) alone were maintained up to 12 weeks postimplantation. The weight of fat graft within the epineural patch was maintained up to 6 weeks, but 50% of weight loss was observed between 6 and 12 weeks. Structure of the epineural sheath tubes and patches was intact, and no leakage of fat graft was observed. Based on hematoxylin and eosin staining, normal structure and integrity of the fat graft within the ET were preserved up to 12 weeks postimplantation. Characteristic adipocyte morphology was confirmed by perilipin staining, showing viable fat cells in groups 3 and 5 at 12 weeks. Increased vascular endothelial growth factor expression was observed in groups 2, 3, 4, and 5. CONCLUSIONS Both, the ETs and epineural patches maintained 100% and 50% of fat graft weight at 12 weeks postimplantation, respectively. These results were confirmed by histology and immunostaining showing viable adipocytes within the epineural patches (6 weeks) and tubes (12 weeks). These results are encouraging and justify further evaluation of fat volume maintenance in preclinical large animal model in preparation to clinical application.
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110
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Shaofu Zhuyu decoction ameliorates obesity-mediated hepatic steatosis and systemic inflammation by regulating metabolic pathways. PLoS One 2017; 12:e0178514. [PMID: 28570676 PMCID: PMC5453538 DOI: 10.1371/journal.pone.0178514] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Accepted: 05/15/2017] [Indexed: 01/07/2023] Open
Abstract
Shaofu Zhuyu decoction (SFZYD, also known as Sobokchugeo-tang), a classical prescription drug in traditional East Asian medicine, has been used to treat blood stasis syndrome (BSS). Hepatic steatosis is the result of excess caloric intake, and its pathogenesis involves internal retention of phlegm and dampness, blood stasis, and liver Qi stagnation. To evaluate the effects of treatment with SFZYD on obesity-induced inflammation and hepatic steatosis, we fed male C57BL/6N mice a high fat diet (HFD) for 8 weeks and then treated them with SFZYD by oral gavage for an additional 4 weeks. The results of histological and biochemical examinations indicated that SFZYD treatment ameliorates systemic inflammation and hepatic steatosis. A partial least squares-discriminant analysis (PLS-DA) scores plot of serum metabolites showed that HFD mice began to produce metabolites similar to those of normal chow (NC) mice after SFZYD administration. We noted significant alterations in the levels of twenty-seven metabolites, alterations indicating that SFZYD regulates the TCA cycle, the pentose phosphate pathway and aromatic amino acid metabolism. Increases in the levels of TCA cycle intermediate metabolites, such as 2-oxoglutaric acid, isocitric acid, and malic acid, in the serum of obese mice were significantly reversed after SFZYD treatment. In addition to inducing changes in the above metabolites, treatment with SFZYD also recovered the expression of genes related to hepatic mitochondrial dysfunction, including Ucp2, Cpt1α, and Ppargc1α, as well as the expression of genes involved in lipid metabolism and inflammation, without affecting glucose uptake or insulin signaling. Taken together, these findings suggest that treatment with SFZYD ameliorated obesity-induced systemic inflammation and hepatic steatosis by regulating inflammatory cytokine and adipokine levels in the circulation and various tissues. Moreover, treatment with SFZYD also reversed alterations in the levels of metabolites of the TCA cycle, the pentose phosphate pathway and aromatic amino acid metabolism.
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111
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Gluchowski NL, Becuwe M, Walther TC, Farese RV. Lipid droplets and liver disease: from basic biology to clinical implications. Nat Rev Gastroenterol Hepatol 2017; 14:343-355. [PMID: 28428634 PMCID: PMC6319657 DOI: 10.1038/nrgastro.2017.32] [Citation(s) in RCA: 377] [Impact Index Per Article: 53.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lipid droplets are dynamic organelles that store neutral lipids during times of energy excess and serve as an energy reservoir during deprivation. Many prevalent metabolic diseases, such as the metabolic syndrome or obesity, often result in abnormal lipid accumulation in lipid droplets in the liver, also called hepatic steatosis. Obesity-related steatosis, or NAFLD in particular, is a major public health concern worldwide and is frequently associated with insulin resistance and type 2 diabetes mellitus. Here, we review the latest insights into the biology of lipid droplets and their role in maintaining lipid homeostasis in the liver. We also offer a perspective of liver diseases that feature lipid accumulation in these lipid storage organelles, which include NAFLD and viral hepatitis. Although clinical applications of this knowledge are just beginning, we highlight new opportunities for identifying molecular targets for treating hepatic steatosis and steatohepatitis.
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Affiliation(s)
- Nina L. Gluchowski
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Boston Children’s Hospital Department of Gastroenterology, Hepatology and Nutrition, 300 Longwood Avenue Boston, Massachusetts 02115, USA
| | - Michel Becuwe
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Tobias C. Walther
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue Boston, Massachusetts 02115, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur Boston, Massachusetts 02115, USA.,Howard Hughes Medical Institute, Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA
| | - Robert V. Farese
- Department of Genetics and Complex Diseases, Harvard T. H. Chan School of Public Health, 655 Huntington Avenue, Boston, Massachusetts 02115, USA.,Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue Boston, Massachusetts 02115, USA.,Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur Boston, Massachusetts 02115, USA
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112
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Lachmann P, Selbmann J, Hickmann L, Hohenstein B, Hugo C, Todorov VT. The PPAR-gamma-binding sequence Pal3 is necessary for basal but dispensable for high-fat diet regulated human renin expression in the kidney. Pflugers Arch 2017; 469:1349-1357. [PMID: 28534088 DOI: 10.1007/s00424-017-1994-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/25/2017] [Accepted: 05/05/2017] [Indexed: 11/30/2022]
Abstract
We reported earlier that PPAR-gamma regulates renin transcription through a human-specific atypical binding sequence termed hRen-Pal3. Here we developed a mouse model to investigate the functional relevance of the hRen-Pal3 sequence in vivo since it might be responsible for the increased renin production in obesity and thus for the development of accompanying arterial hypertension. We used bacterial artificial chromosome construct and co-placement strategy to generate two transgenic mouse lines expressing the human renin gene from identical genomic locus without affecting the intrinsic mouse renin expression. One line carried a wild-type hRen-Pal3 in the transgene (Pal3wt strain) and the other a mutated non-functional Pal3 (Pal3mut strain). Human renin expression was correctly targeted to the renin-producing juxtaglomerular (JG) cells of kidney in both lines. However, Pal3mut mice had lower basal human renin expression. Since human renin does not recognize mouse angiotensinogen as substrate, the blood pressure was not different between the strains. Stimulation of renin production with the angiotensin-converting enzyme inhibitor enalapril equipotentially stimulated the human renin expression in Pal3wt and Pal3mut mice. High-fat diet for 10 weeks which is known to activate PPAR-gamma failed to increase human renin mRNA in kidneys of either strain. These findings showed that the human renin PPAR-gamma-binding sequence hRen-Pal3 is essential for basal renin expression but dispensable for the cell-specific and high-fat diet regulated renin expression in the kidney.
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Affiliation(s)
- Peter Lachmann
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Jenny Selbmann
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Linda Hickmann
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Bernd Hohenstein
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Christian Hugo
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany
| | - Vladimir T Todorov
- Experimental Nephrology, Division of Nephrology, Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307, Dresden, Germany.
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113
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Amato A, Caldara GF, Nuzzo D, Baldassano S, Picone P, Rizzo M, Mulè F, Di Carlo M. NAFLD and Atherosclerosis Are Prevented by a Natural Dietary Supplement Containing Curcumin, Silymarin, Guggul, Chlorogenic Acid and Inulin in Mice Fed a High-Fat Diet. Nutrients 2017; 9:nu9050492. [PMID: 28505074 PMCID: PMC5452222 DOI: 10.3390/nu9050492] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 05/06/2017] [Accepted: 05/09/2017] [Indexed: 12/25/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) confers an increased risk of cardiovascular diseases. NAFDL is associated with atherogenic dyslipidemia, inflammation and renin-angiotensin system (RAS) imbalance, which in turn lead to atherosclerotic lesions. In the present study, the impact of a natural dietary supplement (NDS) containing Curcuma longa, silymarin, guggul, chlorogenic acid and inulin on NAFLD and atherosclerosis was evaluated, and the mechanism of action was examined. C57BL/6 mice were fed an HFD for 16 weeks; half of the mice were simultaneously treated with a daily oral administration (os) of the NDS. NAFLD and atherogenic lesions in aorta and carotid artery (histological analysis), hepatic expression of genes involved in the NAFLD (PCR array), hepatic angiotensinogen (AGT) and AT1R mRNA expression (real-time PCR) and plasma angiotensin (ANG)-II levels (ELISA) were evaluated. In the NDS group, steatosis, aortic lesions or carotid artery thickening was not observed. PCR array showed upregulation of some genes involved in lipid metabolism and anti-inflammatory activity (Cpt2, Ifng) and downregulation of some genes involved in pro-inflammatory response and in free fatty acid up-take (Fabp5, Socs3). Hepatic AGT, AT1R mRNA and ANG II plasma levels were significantly lower with respect to the untreated-group. Furthermore, NDS inhibited the dyslipidemia observed in the untreated animals. Altogether, these results suggest that NDS prevents NAFLD and atherogenesis by modulating the expression of different genes involved in NAFLD and avoiding RAS imbalance.
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Affiliation(s)
- Antonella Amato
- Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo 90128, Italy.
| | - Gaetano-Felice Caldara
- Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo 90128, Italy.
| | - Domenico Nuzzo
- Institute of Biomedicine and Molecular Immunology "Alberto Monroy" (IBIM), Consiglio Nazionale delle Ricerche (CNR), 90146 Palermo, Italy.
| | - Sara Baldassano
- Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo 90128, Italy.
| | - Pasquale Picone
- Institute of Biomedicine and Molecular Immunology "Alberto Monroy" (IBIM), Consiglio Nazionale delle Ricerche (CNR), 90146 Palermo, Italy.
| | - Manfredi Rizzo
- Biomedical Department of Internal Medicine and Medical Specialties, University of Palermo, Palermo 90127, Italy.
| | - Flavia Mulè
- Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Palermo 90128, Italy.
| | - Marta Di Carlo
- Institute of Biomedicine and Molecular Immunology "Alberto Monroy" (IBIM), Consiglio Nazionale delle Ricerche (CNR), 90146 Palermo, Italy.
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The role and regulation of the peroxisome proliferator activated receptor alpha in human liver. Biochimie 2017; 136:75-84. [DOI: 10.1016/j.biochi.2016.12.019] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 12/24/2016] [Accepted: 12/31/2016] [Indexed: 12/16/2022]
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115
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Nagarajan SR, Brandon AE, McKenna JA, Shtein HC, Nguyen TQ, Suryana E, Poronnik P, Cooney GJ, Saunders DN, Hoy AJ. Insulin and diet-induced changes in the ubiquitin-modified proteome of rat liver. PLoS One 2017; 12:e0174431. [PMID: 28329008 PMCID: PMC5362237 DOI: 10.1371/journal.pone.0174431] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 03/08/2017] [Indexed: 12/14/2022] Open
Abstract
Ubiquitin is a crucial post-translational modification regulating numerous cellular processes, but its role in metabolic disease is not well characterized. In this study, we identified the in vivo ubiquitin-modified proteome in rat liver and determined changes in this ubiquitome under acute insulin stimulation and high-fat and sucrose diet-induced insulin resistance. We identified 1267 ubiquitinated proteins in rat liver across diet and insulin-stimulated conditions, with 882 proteins common to all conditions. KEGG pathway analysis of these proteins identified enrichment of metabolic pathways, TCA cycle, glycolysis/gluconeogenesis, fatty acid metabolism, and carbon metabolism, with similar pathways altered by diet and insulin resistance. Thus, the rat liver ubiquitome is sensitive to diet and insulin stimulation and this is perturbed in insulin resistance.
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Affiliation(s)
- Shilpa R. Nagarajan
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Amanda E. Brandon
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Jessie A. McKenna
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Harrison C. Shtein
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Thinh Q. Nguyen
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Eurwin Suryana
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
| | - Philip Poronnik
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
| | - Gregory J. Cooney
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent’s Clinical School, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Darren N. Saunders
- Kinghorn Cancer Centre, Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
- * E-mail: (AJH); (DNS)
| | - Andrew J. Hoy
- Discipline of Physiology, School of Medical Sciences & Bosch Institute, Charles Perkins Centre, University of Sydney, Sydney, NSW, Australia
- * E-mail: (AJH); (DNS)
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116
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Aslibekyan S, Do AN, Xu H, Li S, Irvin MR, Zhi D, Tiwari HK, Absher DM, Shuldiner AR, Zhang T, Chen W, Tanner K, Hong C, Mitchell BD, Berenson G, Arnett DK. CPT1A methylation is associated with plasma adiponectin. Nutr Metab Cardiovasc Dis 2017; 27:225-233. [PMID: 28139377 PMCID: PMC5330786 DOI: 10.1016/j.numecd.2016.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 10/24/2016] [Accepted: 11/14/2016] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND AIMS Adiponectin, an adipose-secreted protein that has been linked to insulin sensitivity, plasma lipids, and inflammatory patterns, is an established biomarker for metabolic health. Despite clinical relevance and high heritability, the determinants of plasma adiponectin levels remain poorly understood. METHODS AND RESULTS We conducted the first epigenome-wide cross-sectional study of adiponectin levels using methylation data on 368,051 cytosine-phosphate-guanine (CpG) sites in CD4+ T-cells from the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN, n = 991). We fit linear mixed models, adjusting for age, sex, study site, T-cell purity, and family. We have identified a positive association (regression coefficient ± SE = 0.01 ± 0.001, P = 3.4 × 10-13) between plasma adiponectin levels and methylation of a CpG site in CPT1A, a key player in fatty acid metabolism. The association was replicated (n = 474, P = 0.0009) in whole blood samples from the Amish participants of the Heredity and Phenotype Intervention (HAPI) Heart Study as well as White (n = 592, P = 0.0005) but not Black (n = 243, P = 0.18) participants of the Bogalusa Heart Study (BHS). The association remained significant upon adjusting for BMI and smoking in GOLDN and HAPI but not BHS. We also identified associations between methylation loci in RNF145 and UFM1 and plasma adiponectin in GOLDN and White BHS participants, although the association was not robust to adjustment for BMI or smoking. CONCLUSION We have identified and replicated associations between several biologically plausible loci and plasma adiponectin. These findings support the importance of epigenetic processes in metabolic traits, laying the groundwork for future translational applications.
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Affiliation(s)
- S Aslibekyan
- Department of Epidemiology, University of Alabama at Birmingham, USA.
| | - A N Do
- Department of Epidemiology, University of Alabama at Birmingham, USA
| | - H Xu
- Department of Medicine, University of Maryland School of Medicine, USA
| | - S Li
- Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, USA
| | - M R Irvin
- Department of Epidemiology, University of Alabama at Birmingham, USA
| | - D Zhi
- Department of Biostatistics, University of Alabama at Birmingham, USA
| | - H K Tiwari
- Department of Biostatistics, University of Alabama at Birmingham, USA
| | - D M Absher
- HudsonAlpha Institute for Biotechnology, USA
| | - A R Shuldiner
- Department of Medicine, University of Maryland School of Medicine, USA
| | - T Zhang
- Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, USA
| | - W Chen
- Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, USA
| | - K Tanner
- Department of Medicine, University of Maryland School of Medicine, USA
| | - C Hong
- Department of Medicine, University of Maryland School of Medicine, USA
| | - B D Mitchell
- Department of Medicine, University of Maryland School of Medicine, USA; Geriatrics Research and Education Clinical Center, Baltimore Veterans Administration Medical Center, Baltimore, MD, USA
| | - G Berenson
- Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, USA
| | - D K Arnett
- Department of Epidemiology, University of Alabama at Birmingham, USA
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117
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Plassais J, Rimbault M, Williams FJ, Davis BW, Schoenebeck JJ, Ostrander EA. Analysis of large versus small dogs reveals three genes on the canine X chromosome associated with body weight, muscling and back fat thickness. PLoS Genet 2017; 13:e1006661. [PMID: 28257443 PMCID: PMC5357063 DOI: 10.1371/journal.pgen.1006661] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 03/17/2017] [Accepted: 02/26/2017] [Indexed: 12/21/2022] Open
Abstract
Domestic dog breeds display significant diversity in both body mass and skeletal size, resulting from intensive selective pressure during the formation and maintenance of modern breeds. While previous studies focused on the identification of alleles that contribute to small skeletal size, little is known about the underlying genetics controlling large size. We first performed a genome-wide association study (GWAS) using the Illumina Canine HD 170,000 single nucleotide polymorphism (SNP) array which compared 165 large-breed dogs from 19 breeds (defined as having a Standard Breed Weight (SBW) >41 kg [90 lb]) to 690 dogs from 69 small breeds (SBW ≤41 kg). We identified two loci on the canine X chromosome that were strongly associated with large body size at 82-84 megabases (Mb) and 101-104 Mb. Analyses of whole genome sequencing (WGS) data from 163 dogs revealed two indels in the Insulin Receptor Substrate 4 (IRS4) gene at 82.2 Mb and two additional mutations, one SNP and one deletion of a single codon, in Immunoglobulin Superfamily member 1 gene (IGSF1) at 102.3 Mb. IRS4 and IGSF1 are members of the GH/IGF1 and thyroid pathways whose roles include determination of body size. We also found one highly associated SNP in the 5'UTR of Acyl-CoA Synthetase Long-chain family member 4 (ACSL4) at 82.9 Mb, a gene which controls the traits of muscling and back fat thickness. We show by analysis of sequencing data from 26 wolves and 959 dogs representing 102 domestic dog breeds that skeletal size and body mass in large dog breeds are strongly associated with variants within IRS4, ACSL4 and IGSF1.
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Affiliation(s)
- Jocelyn Plassais
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Maud Rimbault
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Falina J. Williams
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Brian W. Davis
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jeffrey J. Schoenebeck
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Elaine A. Ostrander
- Cancer Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, United States of America
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118
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Hernández EÁ, Kahl S, Seelig A, Begovatz P, Irmler M, Kupriyanova Y, Nowotny B, Nowotny P, Herder C, Barosa C, Carvalho F, Rozman J, Neschen S, Jones JG, Beckers J, de Angelis MH, Roden M. Acute dietary fat intake initiates alterations in energy metabolism and insulin resistance. J Clin Invest 2017; 127:695-708. [PMID: 28112681 DOI: 10.1172/jci89444] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 11/10/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Dietary intake of saturated fat is a likely contributor to nonalcoholic fatty liver disease (NAFLD) and insulin resistance, but the mechanisms that initiate these abnormalities in humans remain unclear. We examined the effects of a single oral saturated fat load on insulin sensitivity, hepatic glucose metabolism, and lipid metabolism in humans. Similarly, initiating mechanisms were examined after an equivalent challenge in mice. METHODS Fourteen lean, healthy individuals randomly received either palm oil (PO) or vehicle (VCL). Hepatic metabolism was analyzed using in vivo 13C/31P/1H and ex vivo 2H magnetic resonance spectroscopy before and during hyperinsulinemic-euglycemic clamps with isotope dilution. Mice underwent identical clamp procedures and hepatic transcriptome analyses. RESULTS PO administration decreased whole-body, hepatic, and adipose tissue insulin sensitivity by 25%, 15%, and 34%, respectively. Hepatic triglyceride and ATP content rose by 35% and 16%, respectively. Hepatic gluconeogenesis increased by 70%, and net glycogenolysis declined by 20%. Mouse transcriptomics revealed that PO differentially regulates predicted upstream regulators and pathways, including LPS, members of the TLR and PPAR families, NF-κB, and TNF-related weak inducer of apoptosis (TWEAK). CONCLUSION Saturated fat ingestion rapidly increases hepatic lipid storage, energy metabolism, and insulin resistance. This is accompanied by regulation of hepatic gene expression and signaling that may contribute to development of NAFLD.REGISTRATION. ClinicalTrials.gov NCT01736202. FUNDING Germany: Ministry of Innovation, Science, and Research North Rhine-Westfalia, German Federal Ministry of Health, Federal Ministry of Education and Research, German Center for Diabetes Research, German Research Foundation, and German Diabetes Association. Portugal: Portuguese Foundation for Science and Technology, FEDER - European Regional Development Fund, Portuguese Foundation for Science and Technology, and Rede Nacional de Ressonância Magnética Nuclear.
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119
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Abstract
Feline hepatic lipidosis (FHL) is a common and potentially fatal liver disorder. Although the pathophysiologic mechanisms of FHL remain elusive, there is an imbalance between the influx of fatty acids from peripheral fat stores into the liver, de novo liposynthesis, and the rate of hepatic oxidation and dispersal of hepatic TAG via excretion of very-low density lipoproteins. The diagnosis of FHL is based on anamnestic, clinical, and clinicopathologic findings, associated with diagnostic imaging of the liver, and cytology, or histological examination of liver biopsies. Fluid therapy, electrolyte correction and adequate early nutrition are essential components of the therapy for FHL.
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Affiliation(s)
- Chiara Valtolina
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM, Utrecht, The Netherlands.
| | - Robert P Favier
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM, Utrecht, The Netherlands
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120
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Besse-Patin A, Léveillé M, Oropeza D, Nguyen BN, Prat A, Estall JL. Estrogen Signals Through Peroxisome Proliferator-Activated Receptor-γ Coactivator 1α to Reduce Oxidative Damage Associated With Diet-Induced Fatty Liver Disease. Gastroenterology 2017; 152:243-256. [PMID: 27658772 DOI: 10.1053/j.gastro.2016.09.017] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 12/25/2022]
Abstract
BACKGROUND & AIMS Inefficient fatty acid oxidation in mitochondria and increased oxidative damage are features of non-alcoholic fatty liver disease (NAFLD). In rodent models and patients with NAFLD, hepatic expression of peroxisome proliferator-activated receptor-γ (PPARG) coactivator 1α (PPARGC1A or PGC1A) is inversely correlated with liver fat and disease severity. A common polymorphism in this gene (rs8192678, encoding Gly482Ser) has been associated with NAFLD. We investigated whether reduced expression of PGC1A contributes to development of NAFLD using mouse models, primary hepatocytes, and human cell lines. METHODS HepG2 cells were transfected with variants of PPARGC1A and protein and messenger RNA levels were measured. Mice with liver-specific hemizygous or homozygous disruption of Ppargc1a (Ppargc1af/+Alb-cre+/0 and Ppargc1af/f Alb-cre+/0 mice, respectively) were fed regular chow (control) or a high-fat diet supplemented with 30% d-fructose in drinking water (obesogenic diet) for 25-33 weeks. Liver tissues were analyzed by histology and by immunoblotting. Primary hepatocytes were analyzed for insulin signaling, reactive oxygen species, and estrogen response. Luciferase reporter expression was measured in transfected H2.35 cells expressing an estrogen receptor reporter gene, estrogen receptor 1, and/or PGC1A/B. RESULTS The serine 482 variant of the human PGC1A protein had a shorter half-life than the glycine 482 variant when expressed in HepG2 cells. Liver tissues from mice with liver-specific hemizygous disruption of Ppargc1a placed on an obesogenic diet expressed increased markers of inflammation and fibrosis and decreased levels of antioxidant enzymes compared with the Ppargc1a+/+ on the same diet. Oxidative damage was observed in livers from Ppargc1af/+Alb-cre+/0 mice of each sex, in a cell-autonomous manner, but was greater in livers from the female mice. Expression of PGC1A in H2.35 cells coactivated estrogen receptor 1 and was required for estrogen-dependent expression of genes that encode antioxidant proteins. These findings could account for the increased liver damage observed in female Ppargc1af/+Alb-cre+/0 mice; while, compensatory increases in PPARG coactivator 1β could prevent oxidative damage associated with complete loss of PGC1A expression in Ppargc1af/fAlb-cre+/0 female mice. CONCLUSIONS In mice, loss of estrogen signaling contributes to oxidative damage caused by low levels of PGC1A in liver, exacerbating steatohepatitis associated with diets high in fructose and fat.
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Affiliation(s)
- Aurèle Besse-Patin
- Institut de Recherches Cliniques de Montreal, Montreal, Québec, Canada; Department of Medicine, University of Montreal, Montreal, Québec, Canada
| | - Mélissa Léveillé
- Institut de Recherches Cliniques de Montreal, Montreal, Québec, Canada; Department of Medicine, University of Montreal, Montreal, Québec, Canada
| | - Daniel Oropeza
- Institut de Recherches Cliniques de Montreal, Montreal, Québec, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Québec, Canada
| | - Bich N Nguyen
- Department of Pathology and Cell Biology, University of Montreal, Montreal, Québec, Canada; University of Montreal Health Network, Montreal, Québec, Canada
| | - Annik Prat
- Laboratory of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montreal, Montreal, Québec, Canada
| | - Jennifer L Estall
- Institut de Recherches Cliniques de Montreal, Montreal, Québec, Canada; Department of Medicine, University of Montreal, Montreal, Québec, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Québec, Canada.
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121
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Ajmera V, Perito ER, Bass NM, Terrault NA, Yates KP, Gill R, Loomba R, Diehl AM, Aouizerat B. Novel plasma biomarkers associated with liver disease severity in adults with nonalcoholic fatty liver disease. Hepatology 2017; 65:65-77. [PMID: 27532276 PMCID: PMC5191932 DOI: 10.1002/hep.28776] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 06/02/2016] [Accepted: 08/02/2016] [Indexed: 02/06/2023]
Abstract
UNLABELLED Despite the high prevalence of nonalcoholic fatty liver disease (NAFLD), therapeutic options and noninvasive markers of disease activity and severity remain limited. We investigated the association between plasma biomarkers and liver histology in order to identify markers of disease activity and severity in patients with biopsy-proven NAFLD. Thirty-two plasma biomarkers chosen a priori as possible discriminators of NAFLD were measured in participants enrolled in the Nonalcoholic Steatohepatitis (NASH) Clinical Research Network. Dichotomized histologic outcomes were evaluated using centrally read biopsies. Biomarkers with statistically significant associations with NAFLD histology were evaluated in multivariable models adjusted for clinical factors. Of 648 participants (74.4% white, 61.7% female, mean age 47.7 years), 58.0% had definite NASH, 55.5% had mild/no fibrosis (stage 0-1), and 44.4% had significant fibrosis (stage 2-4). Increased activated plasminogen activator inhibitor 1 had a strong association with definite NASH compared to not NASH or borderline NASH in multivariable analysis (odds ratio = 1.20, 95% confidence interval 1.08-1.34, P < 0.001). Biomarkers associated with significant fibrosis (versus mild/no fibrosis) in multivariable analysis included higher levels of interleukin-8, monocyte chemoattractant protein-1, resistin, soluble interleukin-1 receptor I, soluble interleukin-2 receptor alpha, and tumor necrosis factor alpha and lower levels of insulin-like growth factor 2. CONCLUSIONS Specific plasma biomarkers are significantly associated with disease activity and severity of fibrosis in NAFLD and are potentially valuable tools for noninvasive stratification of patients with NAFLD and identification of targets for therapeutic intervention. (Hepatology 2017;65:65-77).
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Affiliation(s)
- Veeral Ajmera
- Gastroenterology, UCSF, San Francisco, CA, United States
| | - Emily R. Perito
- Pediatric Gastroenterology, UCSF, San Francisco, CA, United States
| | - Nathan M. Bass
- Gastroenterology, UCSF, San Francisco, CA, United States
| | | | | | - Ryan Gill
- Pathology, UCSF, San Francisco, CA, United States
| | - Rohit Loomba
- Gastroenterology, UCSD, San Diego, CA, United States
| | - Anna Mae Diehl
- Gastroenterology, Duke University, Durham, NC, United States
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122
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Changes in liver proteins of rats fed standard and high-fat and sucrose diets induced by fish omega-3 PUFAs and their combination with grape polyphenols according to quantitative proteomics. J Nutr Biochem 2016; 41:84-97. [PMID: 28064013 DOI: 10.1016/j.jnutbio.2016.12.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 11/05/2016] [Accepted: 12/15/2016] [Indexed: 12/16/2022]
Abstract
This study considered the physiological modulation of liver proteins due to the supplementation with fish oils under two dietary backgrounds: standard or high in fat and sucrose (HFHS), and their combination with grape polyphenols. By using a quantitative proteomics approach, we showed that the capacity of the supplements for regulating proteins depended on the diet; namely, 10 different proteins changed into standard diets, while 45 changed into the HFHS diets and only scarcely proteins were found altered in common. However, in both contexts, fish oils were the main regulatory force, although the addition of polyphenols was able to modulate some fish oils' effects. Moreover, we demonstrated the ability of fish oils and their combination with grape polyphenols in improving biochemical parameters and reducing lipogenesis and glycolysis enzymes, enhancing fatty acid beta-oxidation and insulin signaling and ameliorating endoplasmic reticulum stress and protein oxidation when they are included in an unhealthy diet.
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123
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Asakura M, Fukami T, Nakajima M, Fujii H, Atsuda K, Itoh T, Fujiwara R. Hepatic Dipeptidyl Peptidase-4 Controls Pharmacokinetics of Vildagliptin In Vivo. Drug Metab Dispos 2016; 45:237-245. [PMID: 27895112 DOI: 10.1124/dmd.116.073866] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 11/23/2016] [Indexed: 12/24/2022] Open
Abstract
The main route of elimination of vildagliptin, which is an inhibitor of dipeptidyl peptidase-4 (DPP-4), in humans is cyano group hydrolysis to produce a carboxylic acid metabolite M20.7. Our in vitro study previously demonstrated that DPP-4 itself greatly contributed to the hydrolysis of vildagliptin in mouse, rat, and human livers. To investigate whether hepatic DPP-4 contributes to the hydrolysis of vildagliptin in vivo, in the present study, we conducted in vivo pharmacokinetics studies of vildagliptin in mice coadministered with vildagliptin and sitagliptin, which is another DPP-4 inhibitor, and also in streptozotocin (STZ)-induced diabetic mice. The area under the plasma concentration-time curve (AUC) value of M20.7 in mice coadministered with vildagliptin and sitagliptin was significantly lower than that in mice administered vildagliptin alone (P < 0.01). Although plasma DPP-4 expression level was increased 1.9-fold, hepatic DPP-4 activity was decreased in STZ-induced diabetic mice. The AUC values of M20.7 in STZ-induced diabetic mice were lower than those in control mice (P < 0.01). Additionally, the AUC values of M20.7 significantly positively correlated with hepatic DPP-4 activities in the individual mice (Rs = 0.943, P < 0.05). These findings indicated that DPP-4 greatly contributed to the hydrolysis of vildagliptin in vivo and that not plasma, but hepatic DPP-4 controlled pharmacokinetics of vildagliptin. Furthermore, enzyme assays of 23 individual human liver samples showed that there was a 3.6-fold interindividual variability in vildagliptin-hydrolyzing activities. Predetermination of the interindividual variability of hepatic vildagliptin-hydrolyzing activity might be useful for the prediction of blood vildagliptin concentrations in vivo.
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Affiliation(s)
- Mitsutoshi Asakura
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Tatsuki Fukami
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Miki Nakajima
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Hideaki Fujii
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Koichiro Atsuda
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Tomoo Itoh
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
| | - Ryoichi Fujiwara
- Graduate School of Pharmaceutical Sciences (M.A.), Medicinal Research Laboratories (H.F.), Center for Clinical Pharmacy and Clinical Sciences (M.A., K.A.), Laboratory of Medicinal Chemistry (H.F.), and Department of Pharmaceutics (T.I., R.F.), School of Pharmacy, Kitasato University, Tokyo, Japan; Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kanazawa, Japan (T.F., M.N.)
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Genomics of human fatty liver disease reveal mechanistically linked lipid droplet-associated gene regulations in bland steatosis and nonalcoholic steatohepatitis. Transl Res 2016; 177:41-69. [PMID: 27376874 DOI: 10.1016/j.trsl.2016.06.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 05/13/2016] [Accepted: 06/08/2016] [Indexed: 12/11/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common disorder hallmarked by excessive lipid deposits. Based on our recent research on lipid droplet (LD) formation in hepatocytes, we investigated LD-associated gene regulations in NAFLD of different grades, that is, steatosis vs steatohepatitis by comparing liver biopsies from healthy controls (N = 13) and NAFLD patients (N = 102). On average, more than 700 differentially expressed genes (DEGs) were identified of which 146 are mechanistically linked to LD formation. We identified 51 LD-associated DEGs frequently regulated in patient samples (range ≥5 to ≤102) with the liver-receptor homolog-1(NR5A2), that is, a key regulator of cholesterol metabolism being commonly repressed among 100 patients examined. With bland steatosis, notable regulations involved hypoxia-inducible lipid droplet-associated-protein and diacylglycerol-O-acyltransferase-2 renowned for their role in LD-growth. Conversely, nonalcoholic steatohepatitis-associated DEGs coded for epidermal growth factor receptor and TLR4 signaling with decreased expression of the GTPase Rab5 and the lipid phosphohydrolase PPAP2B thus highlighting adaptive responses to inflammation, LDL-mediated endocytosis and lipogenesis, respectively. Studies with steatotic primary human hepatocyte cultures demonstrated induction of LD-associated PLIN2, CIDEC, DNAAF1, whereas repressed expression of CPT1A, ANGPTL4, and PKLR informed on burdened mitochondrial metabolism. Equally, repressed expression of the B-lymphocyte chemoattractant CXCL13 and STAT4 as well as induced FGF21 evidenced amelioration of steatosis-related inflammation. In-vitro/in-vivo patient sample comparisons confirmed C-reactive protein, SOCS3, NR5A2, and SOD2 as commonly regulated. Lastly, STRING network analysis highlighted potential "druggable" targets with PLIN2, CIDEC, and hypoxia-inducible lipid droplet-associated-protein being confirmed by immunofluorescence microscopy. In conclusion, steatosis and steatohepatitis specific gene regulations informed on the pathogenesis of NAFLD to broaden the perspective of targeted therapies.
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125
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Soofi A, Wolf KI, Ranghini EJ, Amin MA, Dressler GR. The kielin/chordin-like protein KCP attenuates nonalcoholic fatty liver disease in mice. Am J Physiol Gastrointest Liver Physiol 2016; 311:G587-G598. [PMID: 27514479 PMCID: PMC5142198 DOI: 10.1152/ajpgi.00165.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/10/2016] [Indexed: 01/31/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease and is increasing with the rising rate of obesity in the developed world. Signaling pathways known to influence the rate of lipid deposition in liver, known as hepatic steatosis, include the transforming growth factor (TGF) superfamily, which function through the SMAD second messengers. The kielin/chordin-like protein (KCP) is a large secreted protein that can enhance bone morphogenetic protein signaling while suppressing TGF-β signaling in cells and in genetically modified mice. In this report, we show that aging KCP mutant (Kcp-/-) mice are increasingly susceptible to developing hepatic steatosis and liver fibrosis. When young mice are put on a high-fat diet, Kcp-/- mice are also more susceptible to developing liver pathology, compared with their wild-type littermates. Furthermore, mice that express a Pepck-KCP transgene (KcpTg) in the liver are resistant to developing liver pathology even when fed a high-fat diet. Analyses of liver tissues reveal a significant reduction of P-Smad3, consistent with a role for KCP in suppressing TGF-β signaling. Transcriptome analyses show that livers from Kcp-/- mice fed a normal diet are more like wild-type livers from mice fed a high-fat diet. However, the KCP transgene can suppress many of the changes in liver gene expression that are due to a high-fat diet. These data demonstrate that shifting the TGF-β signaling paradigm with the secreted regulatory protein KCP can significantly alter the liver pathology in aging mice and in diet-induced NAFLD.
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Affiliation(s)
- Abdul Soofi
- 1Department of Pathology, University of Michigan, Ann Arbor, Michigan; and
| | - Katherine I. Wolf
- 1Department of Pathology, University of Michigan, Ann Arbor, Michigan; and
| | - Egon J. Ranghini
- 1Department of Pathology, University of Michigan, Ann Arbor, Michigan; and
| | - Mohammad A. Amin
- 2Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
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126
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Cranberry extract attenuates hepatic inflammation in high-fat-fed obese mice. J Nutr Biochem 2016; 37:60-66. [PMID: 27619543 DOI: 10.1016/j.jnutbio.2016.07.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/20/2016] [Accepted: 07/05/2016] [Indexed: 01/07/2023]
Abstract
Cranberry (Vaccinium macrocarpon) consumption has been associated with health beneficial effects. Nonalcoholic fatty liver disease (NAFLD) is a comorbidity of obesity. In the present study, we investigated the effect of a polyphenol-rich cranberry extract (CBE) on hepatic inflammation in high fat (HF)-fed obese C57BL/6J mice. Following dietary treatment with 0.8% CBE for 10 weeks, we observed no change in body weight or visceral fat mass in CBE-supplemented mice compared to HF-fed control mice. We did observe a significant decrease in plasma alanine aminotransferase (31%) and histological severity of NAFLD (33% decrease in area of involvement, 29% decrease in lipid droplet size) compared to HF-fed controls. Hepatic protein levels of tumor necrosis factor α and C-C chemokine ligand 2 were reduced by 28% and 19%, respectively, following CBE supplementation. CBE significantly decreased hepatic mRNA levels of toll-like receptor 4 (TLR4, 63%) and nuclear factor κB (NFκB, 24%), as well as a number of genes related to the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing 3 inflammasome. In conclusion, CBE reduced NAFLD and hepatic inflammation in HF-fed obese C57BL/6J mice. These effects appear to be related to mitigation of TLR4-NFκB related signaling; however, further studies into the underlying mechanisms of these hepatoprotective effects are needed.
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127
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Caloric restriction of db/db mice reverts hepatic steatosis and body weight with divergent hepatic metabolism. Sci Rep 2016; 6:30111. [PMID: 27439777 PMCID: PMC4954985 DOI: 10.1038/srep30111] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 06/27/2016] [Indexed: 01/04/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent causes of liver disease and its prevalence is a serious and growing clinical problem. Caloric restriction (CR) is commonly recommended for improvement of obesity-related diseases such as NAFLD. However, the effects of CR on hepatic metabolism remain unknown. We investigated the effects of CR on metabolic dysfunction in the liver of obese diabetic db/db mice. We found that CR of db/db mice reverted insulin resistance, hepatic steatosis, body weight and adiposity to those of db/m mice. 1H-NMR- and UPLC-QTOF-MS-based metabolite profiling data showed significant metabolic alterations related to lipogenesis, ketogenesis, and inflammation in db/db mice. Moreover, western blot analysis showed that lipogenesis pathway enzymes in the liver of db/db mice were reduced by CR. In addition, CR reversed ketogenesis pathway enzymes and the enhanced autophagy, mitochondrial biogenesis, collagen deposition and endoplasmic reticulum stress in db/db mice. In particular, hepatic inflammation-related proteins including lipocalin-2 in db/db mice were attenuated by CR. Hepatic metabolomic studies yielded multiple pathological mechanisms of NAFLD. Also, these findings showed that CR has a therapeutic effect by attenuating the deleterious effects of obesity and diabetes-induced multiple complications.
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128
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Roles of the interorgan neuronal network in the development of metabolic syndrome. Diabetol Int 2016; 7:205-211. [PMID: 30603265 DOI: 10.1007/s13340-016-0277-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 06/26/2016] [Indexed: 01/01/2023]
Abstract
Metabolic processes in different tissues and remote organs are under coordinated systemic regulation, allowing adaptation to a variety of external circumstances. Neuronal signals as well as humoral factors, such as nutrients, growth factors, and hormones, have attracted increasing attention for their roles in this interorgan metabolic network, responsible for the maintenance of metabolic homeostasis at the whole-body level. These interorgan communications within an organism are considered to be diverse and, in fact, we identified previously unknown neuronal relay systems originating in the liver which modulate energy, glucose, and lipid metabolism. Furthermore, when nutrient overload is prolonged, these neuronal mechanisms, which function as an endogenous defense system against obesity development, contribute to the pathophysiological states of metabolic syndrome characterized by obesity-associated features. Therefore, these interorgan neuronal systems are considered to be possible molecular targets for treating metabolic syndrome. We herein review the precise mechanisms underlying the functions of the mammalian interorgan neuronal network, especially the pathways from the liver to several other organs, focusing on their significance and roles in the development of metabolic syndrome.
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129
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Lo J, Lu MT, Kim EA, Nou E, Hallett TR, Park J, Hoffmann U, Grinspoon SK. Statin Effects to Reduce Hepatosteatosis as Measured by Computed Tomography in Patients With Human Immunodeficiency Virus. Open Forum Infect Dis 2016; 3:ofw062. [PMID: 27419149 PMCID: PMC4943550 DOI: 10.1093/ofid/ofw062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 03/18/2016] [Indexed: 12/28/2022] Open
Abstract
Hepatosteatosis is highly prevalent among patients living with human immunodeficiency virus. In a 1-year, randomized, double-blind trial of atorvastatin or placebo, atorvastatin increased liver/spleen ratio among patients with nonalcoholic fatty liver disease, indicating a reduction in hepatosteatosis. This reduction in hepatosteatosis is associated with reduction in low-density lipoprotein cholesterol with statin therapy.
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Affiliation(s)
- Janet Lo
- Department of Medicine, Endocrine Division, Program in Nutritional Metabolism , Massachusetts General Hospital and Harvard Medical School , and
| | - Michael T Lu
- Department of Radiology, Cardiac PET MR CT Program , Massachusetts General Hospital, and Harvard Medical School , Boston
| | - Elli A Kim
- Department of Medicine, Endocrine Division, Program in Nutritional Metabolism , Massachusetts General Hospital and Harvard Medical School , and
| | - Eric Nou
- Department of Medicine, Endocrine Division, Program in Nutritional Metabolism , Massachusetts General Hospital and Harvard Medical School , and
| | - Travis R Hallett
- Department of Radiology, Cardiac PET MR CT Program , Massachusetts General Hospital, and Harvard Medical School , Boston
| | - Jakob Park
- Department of Radiology, Cardiac PET MR CT Program , Massachusetts General Hospital, and Harvard Medical School , Boston
| | - Udo Hoffmann
- Department of Radiology, Cardiac PET MR CT Program , Massachusetts General Hospital, and Harvard Medical School , Boston
| | - Steven K Grinspoon
- Department of Medicine, Endocrine Division, Program in Nutritional Metabolism , Massachusetts General Hospital and Harvard Medical School , and
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130
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Ponziani FR, Pecere S, Gasbarrini A, Ojetti V. Physiology and pathophysiology of liver lipid metabolism. Expert Rev Gastroenterol Hepatol 2016; 9:1055-67. [PMID: 26070860 DOI: 10.1586/17474124.2015.1056156] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Liver lipid metabolism and its modulation are involved in many pathologic conditions, such as obesity, non-alcoholic fatty liver disease, diabetes mellitus, atherosclerosis and cardiovascular disease. Metabolic disorders seem to share a similar background of low-grade chronic inflammation, even if the pathophysiological mechanisms leading to tissue and organ damage have not been completely clarified yet. The accumulation of neutral lipids in the liver is now recognized as a beneficial and protective mechanism; on the other hand, lipoperoxidation is involved in the development and progression of non-alcoholic steatohepatitis. The role of the gut microbiota in liver lipid metabolism has been the object of recent scientific investigations. It is likely that the gut microbiota is involved in a complex metabolic modulation and the translocation of gut microflora may also contribute to maintaining the low-grade inflammatory status of metabolic syndrome. Therefore, lipid metabolism pathology has vague limits and complex mechanisms, and the knowledge of these is essential to guide diagnostic and therapeutic decisions.
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131
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Pinolenic Acid Downregulates Lipid Anabolic Pathway in HepG2 Cells. Lipids 2016; 51:847-55. [DOI: 10.1007/s11745-016-4149-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 03/31/2016] [Indexed: 12/15/2022]
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132
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Cafeteria diet-induced obesity causes oxidative damage in white adipose. Biochem Biophys Res Commun 2016; 473:545-50. [PMID: 27033600 DOI: 10.1016/j.bbrc.2016.03.113] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 03/23/2016] [Indexed: 01/01/2023]
Abstract
Obesity continues to be one of the most prominent public health dilemmas in the world. The complex interaction among the varied causes of obesity makes it a particularly challenging problem to address. While typical high-fat purified diets successfully induce weight gain in rodents, we have described a more robust model of diet-induced obesity based on feeding rats a diet consisting of highly palatable, energy-dense human junk foods - the "cafeteria" diet (CAF, 45-53% kcal from fat). We previously reported that CAF-fed rats became hyperphagic, gained more weight, and developed more severe hyperinsulinemia, hyperglycemia, and glucose intolerance compared to the lard-based 45% kcal from fat high fat diet-fed group. In addition, the CAF diet-fed group displayed a higher degree of inflammation in adipose and liver, mitochondrial dysfunction, and an increased concentration of lipid-derived, pro-inflammatory mediators. Building upon our previous findings, we aimed to determine mechanisms that underlie physiologic findings in the CAF diet. We investigated the effect of CAF diet-induced obesity on adipose tissue specifically using expression arrays and immunohistochemistry. Genomic evidence indicated the CAF diet induced alterations in the white adipose gene transcriptome, with notable suppression of glutathione-related genes and pathways involved in mitigating oxidative stress. Immunohistochemical analysis indicated a doubling in adipose lipid peroxidation marker 4-HNE levels compared to rats that remained lean on control standard chow diet. Our data indicates that the CAF diet drives an increase in oxidative damage in white adipose tissue that may affect tissue homeostasis. Oxidative stress drives activation of inflammatory kinases that can perturb insulin signaling leading to glucose intolerance and diabetes.
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133
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Ballestri S, Nascimbeni F, Romagnoli D, Baldelli E, Lonardo A. The Role of Nuclear Receptors in the Pathophysiology, Natural Course, and Drug Treatment of NAFLD in Humans. Adv Ther 2016; 33:291-319. [PMID: 26921205 DOI: 10.1007/s12325-016-0306-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) describes steatosis, nonalcoholic steatohepatitis with or without fibrosis, and hepatocellular carcinoma, namely the entire alcohol-like spectrum of liver disease though observed in the nonalcoholic, dysmetabolic, individual free of competing causes of liver disease. NAFLD, which is a major public health issue, exhibits intrahepatic triglyceride storage giving rise to lipotoxicity. Nuclear receptors (NRs) are transcriptional factors which, activated by ligands, are master regulators of metabolism and also have intricate connections with circadian control accounting for cyclical patterns in the metabolic fate of nutrients. Several transcription factors, such as peroxisome proliferator-activated receptors, liver X receptors, farnesoid X receptors, and their molecular cascades, finely regulate energetic fluxes and metabolic pathways. Dysregulation of such pathways is heavily implicated in those metabolic derangements characterizing insulin resistance and metabolic syndrome and in the histogenesis of progressive NAFLD forms. We review the role of selected NRs in NAFLD pathogenesis. Secondly, we analyze the role of NRs in the natural history of human NAFLD. Next, we discuss the results observed in humans following administration of drug agonists or antagonists of the NRs pathogenically involved in NAFLD. Finally, general principles of treatment and lines of research in human NAFLD are briefly examined.
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Affiliation(s)
| | - Fabio Nascimbeni
- NOCSAE, Outpatient Liver Clinic and Operating Unit Internal Medicine, Azienda USL Modena, Modena, Italy
- University of Modena and Reggio Emilia, Modena, Italy
| | - Dante Romagnoli
- NOCSAE, Outpatient Liver Clinic and Operating Unit Internal Medicine, Azienda USL Modena, Modena, Italy
| | | | - Amedeo Lonardo
- NOCSAE, Outpatient Liver Clinic and Operating Unit Internal Medicine, Azienda USL Modena, Modena, Italy.
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134
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Hyötyläinen T, Jerby L, Petäjä EM, Mattila I, Jäntti S, Auvinen P, Gastaldelli A, Yki-Järvinen H, Ruppin E, Orešič M. Genome-scale study reveals reduced metabolic adaptability in patients with non-alcoholic fatty liver disease. Nat Commun 2016; 7:8994. [PMID: 26839171 DOI: 10.1038/ncomms9994] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/22/2015] [Indexed: 12/14/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a major risk factor leading to chronic liver disease and type 2 diabetes. Here we chart liver metabolic activity and functionality in NAFLD by integrating global transcriptomic data, from human liver biopsies, and metabolic flux data, measured across the human splanchnic vascular bed, within a genome-scale model of human metabolism. We show that an increased amount of liver fat induces mitochondrial metabolism, lipolysis, glyceroneogenesis and a switch from lactate to glycerol as substrate for gluconeogenesis, indicating an intricate balance of exacerbated opposite metabolic processes in glycemic regulation. These changes were associated with reduced metabolic adaptability on a network level in the sense that liver fat accumulation puts increasing demands on the liver to adaptively regulate metabolic responses to maintain basic liver functions. We propose that failure to meet excessive metabolic challenges coupled with reduced metabolic adaptability may lead to a vicious pathogenic cycle leading to the co-morbidities of NAFLD.
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Affiliation(s)
- Tuulia Hyötyläinen
- Department of Systems Medicine, Steno Diabetes Center, Niels Steensens Vej 6, Gentofte, DK-2820, Denmark.,VTT Technical Research Centre of Finland, Espoo, FI-02044 VTT, Finland
| | - Livnat Jerby
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Elina M Petäjä
- Department of Medicine, Division of Diabetes, University of Helsinki, Helsinki, FI-00014, Finland.,Minerva Foundation Institute for Medical Research, Helsinki FI-00290, Finland
| | - Ismo Mattila
- Department of Systems Medicine, Steno Diabetes Center, Niels Steensens Vej 6, Gentofte, DK-2820, Denmark.,VTT Technical Research Centre of Finland, Espoo, FI-02044 VTT, Finland
| | - Sirkku Jäntti
- VTT Technical Research Centre of Finland, Espoo, FI-02044 VTT, Finland.,Faculty of Pharmacy, University of Helsinki, Helsinki FI-00014, Finland
| | - Petri Auvinen
- Institute of Biotechnology, DNA Sequencing and Genomics Laboratory, University of Helsinki, Helsinki FI-00014, Finland
| | - Amalia Gastaldelli
- Institute of Clinical Physiology, National Research Council, Pisa 56124, Italy
| | - Hannele Yki-Järvinen
- Department of Medicine, Division of Diabetes, University of Helsinki, Helsinki, FI-00014, Finland.,Minerva Foundation Institute for Medical Research, Helsinki FI-00290, Finland
| | - Eytan Ruppin
- Blavatnik School of Computer Science, Tel Aviv University, Tel Aviv 69978, Israel.,Center for BioInformatics and Computational Biology, Department of Computer Science, University of Maryland, College Park, Maryland 20742, USA
| | - Matej Orešič
- Department of Systems Medicine, Steno Diabetes Center, Niels Steensens Vej 6, Gentofte, DK-2820, Denmark.,VTT Technical Research Centre of Finland, Espoo, FI-02044 VTT, Finland.,Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku FI-20520, Finland
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135
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Søfteland L, Berntssen MH, Kirwan JA, Størseth TR, Viant MR, Torstensen BE, Waagbø R, Olsvik PA. Omega-3 and alpha-tocopherol provide more protection against contaminants in novel feeds for Atlantic salmon ( Salmo salar L.) than omega-6 and gamma tocopherol. Toxicol Rep 2016; 3:211-224. [PMID: 28959541 PMCID: PMC5615787 DOI: 10.1016/j.toxrep.2016.01.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 12/23/2015] [Accepted: 01/11/2016] [Indexed: 11/20/2022] Open
Abstract
Extended use of plant ingredients in Atlantic salmon farming has increased the need for knowledge on the effects of new nutrients and contaminants in plant based feeds on fish health and nutrient-contaminant interactions. Primary Atlantic salmon hepatocytes were exposed to a mixture of PAHs and pesticides alone or in combination with the nutrients ARA, EPA, α-tocopherol, and γ-tocopherol according to a factorial design. Cells were screened for effects using xCELLigence cytotoxicity screening, NMR spectroscopy metabolomics, mass spectrometry lipidomics and RT-qPCR transcriptomics. The cytotoxicity results suggest that adverse effects of the contaminants can be counteracted by the nutrients. The lipidomics suggested effects on cell membrane stability and vitamin D metabolism after contaminant and fatty acid exposure. Co-exposure of the contaminants with EPA or α-tocopherol contributed to an antagonistic effect in exposed cells, with reduced effects on the VTG and FABP4 transcripts. ARA and γ-tocopherol strengthened the contaminant-induced response, ARA by contributing to an additive and synergistic induction of CYP1A, CYP3A and CPT2, and γ-tocopherol by synergistically increasing ACOX1. Individually EPA and α-tocopherol seemed more beneficial than ARA and γ-tocopherol in preventing the adverse effects induced by the contaminant mixture, though a combination of all nutrients showed the greatest ameliorating effect.
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Affiliation(s)
- Liv Søfteland
- National Institute of Nutrition and Seafood Research, Norway
| | | | | | | | - Mark R. Viant
- School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | | | - Rune Waagbø
- National Institute of Nutrition and Seafood Research, Norway
| | - Pål A. Olsvik
- National Institute of Nutrition and Seafood Research, Norway
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136
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Pardina E, Ferrer R, Rossell J, Baena-Fustegueras JA, Lecube A, Fort JM, Caubet E, González Ó, Vilallonga R, Vargas V, Balibrea JM, Peinado-Onsurbe J. Diabetic and dyslipidaemic morbidly obese exhibit more liver alterations compared with healthy morbidly obese. BBA CLINICAL 2016; 5:54-65. [PMID: 27051590 PMCID: PMC4802404 DOI: 10.1016/j.bbacli.2015.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/17/2015] [Accepted: 12/22/2015] [Indexed: 12/14/2022]
Abstract
Background & aims To study the origin of fat excess in the livers of morbidly obese (MO) individuals, we analysed lipids and lipases in both plasma and liver and genes involved in lipid transport, or related with, in that organ. Methods Thirty-two MO patients were grouped according to the absence (healthy: DM − DL −) or presence of comorbidities (dyslipidemic: DM − DL +; or dyslipidemic with type 2 diabetes: DM + DL +) before and one year after gastric bypass. Results The livers of healthy, DL and DM patients contained more lipids (9.8, 9.5 and 13.7 times, respectively) than those of control subjects. The genes implicated in liver lipid uptake, including HL, LPL, VLDLr, and FAT/CD36, showed increased expression compared with the controls. The expression of genes involved in lipid-related processes outside of the liver, such as apoB, PPARα and PGC1α, CYP7a1 and HMGCR, was reduced in these patients compared with the controls. PAI1 and TNFα gene expression in the diabetic livers was increased compared with the other obese groups and control group. Increased steatosis and fibrosis were also noted in the MO individuals. Conclusions Hepatic lipid parameters in MO patients change based on their comorbidities. The gene expression and lipid levels after bariatric surgery were less prominent in the diabetic patients. Lipid receptor overexpression could enable the liver to capture circulating lipids, thus favouring the steatosis typically observed in diabetic and dyslipidaemic MO individuals. The criteria used to define the “metabolically healthy” obese is not applicable to morbidly obese patients. Virtually no studies of how bariatric surgery affects depending on comorbidities and less how affect to the liver. Anthropometrics, fat, lipid profile and inflammation parameters are different depending of comorbidities, not only in plasma but also in liver. The extent of lipases and lipids in the liver biopsies could help not only the diagnosis but also to follow the course of recovery after surgery. The morbidly obese individuals with diabetes and dyslipidemia have more altered metabolic profiles than the other two groups.
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Key Words
- ALT, Alanine transaminase
- AST, Aspartate transaminase
- ATGL, Adipose Tissue Glycerol Lipase
- ApoA1, Apolipoprotein A1
- BMI, Body Mass Index
- CPT1a, Carnitine Palmitoyltransferase 1a
- CRP, C-reactive protein
- CYP7a1, Cholesterol 7 Alpha-Hydroxylase
- DL, Dyslipidaemia
- DM, Type 2 diabetes mellitus
- DM + DL +, Obese patients with type 2 diabetes and dyslipidaemia
- DM − DL +, Dyslipidemic obese patients
- DM − DL −, “Healthy” obese patients, or patients without type 2 diabetes or dyslipidaemia
- Diabetes
- FAT/CD36, Fatty Acid Translocase or Cluster of Differentiation 36
- GGT, gamma-glutaryl transferase
- HL, Hepatic lipase
- HMGCR, 3-Hydroxy-3-Methylglutaryl-CoA Reductase
- HOMA-IR, Homeostasis Model Assessment of Insulin Resistance
- HSL, Hormone-sensitive lipase
- HTA, Hypertension
- IL6, Interleukin-6
- IR, Insulin resistance
- KBs, Ketone bodies
- LDLr, Low-Density Lipoprotein receptor
- Lipases
- Lipids
- Liver
- MO, Morbidly obese
- NAFLD
- NAFLD, Non-alcoholic fatty liver disease
- NASH, Non-alcoholic liver steatohepatitis
- NEFA, Non-esterified fatty acid
- PAI1, Plasminogen Activator Inhibitor of Type 1
- PLs, Phospholipids
- PPARα, Peroxisome Proliferator-Activated Receptor alpha
- PPARα, Peroxisome Proliferator-Activated Receptor gamma Coactivator 1-alpha
- QMs, Chylomicrons
- RYGBP, Roux-en-Y gastric bypass
- SAT, Subcutaneous adipose tissue
- SCARB1, Scavenger Receptor Class B, Member 1
- Steatosis
- TAGs, Triacylglycerides
- TC, Total cholesterol
- TNFα, Tumour Necrosis Factor-alpha
- UCP2, Uncoupling Protein 2
- VAT, Visceral adipose tissue
- VLDLr, Very-Low-Density Lipoprotein receptor
- apoB, Apolipoprotein B
- cHDL, High-Density Lipoprotein Cholesterol
- cLDL, Low-Density Lipoprotein Cholesterol
- eNOS3, Endothelial Nitric Oxide Synthase 3
- iNOS2, Inducible Nitric Oxide Synthase 2
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Affiliation(s)
- Eva Pardina
- Biochemistry and Molecular Biology Department, Biology Faculty, Barcelona University, Spain
| | - Roser Ferrer
- Biochemistry Department, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Joana Rossell
- Biochemistry and Molecular Biology Department, Biology Faculty, Barcelona University, Spain
| | | | - Albert Lecube
- Endocrinology and Nutrition Department, Arnau de Vilanova University Hospital (UdL), Diabetes and Metabolism Research Unit (VHIR, UAB), CIBER de Diabetes y Enfermedades Metabólicas (CIBERDEM) del Instituto de Salud Carlos III, Spain
| | - Jose Manuel Fort
- Endocrinology Surgery Unit, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Enric Caubet
- Endocrinology Surgery Unit, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Óscar González
- Endocrinology Surgery Unit, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Ramón Vilallonga
- Endocrinology Surgery Unit, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Víctor Vargas
- CIBER de Enfermedades Hepáticas y Digestivas (CIBEREHD) del Instituto de Salud Carlos III (ISCIII), Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - José María Balibrea
- Endocrinology Surgery Unit, Hospital Universitari Vall D'Hebron, Universitat Autònoma de Barcelona, Spain
| | - Julia Peinado-Onsurbe
- Biochemistry and Molecular Biology Department, Biology Faculty, Barcelona University, Spain
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137
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Ham JR, Lee HI, Choi RY, Sim MO, Seo KI, Lee MK. Anti-steatotic and anti-inflammatory roles of syringic acid in high-fat diet-induced obese mice. Food Funct 2016; 7:689-697. [DOI: 10.1039/c5fo01329a] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/29/2023]
Abstract
This study examined the effects of syringic acid (SA) on obese diet-induced hepatic dysfunction.
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Affiliation(s)
- Ju Ri Ham
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
| | - Hae-In Lee
- Mokpo Marin Food-Industry Research Center
- Mokpo
- Korea
| | - Ra-Yeong Choi
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
| | - Mi-Ok Sim
- Jeollanamdo Development Institute of Korean Traditional Medicine
- Jangheung
- Korea
| | - Kwon-Il Seo
- Department of Biotechnology
- Dong-A University
- Busan
- Korea
| | - Mi-Kyung Lee
- Department of Food and Nutrition
- Sunchon National University
- Suncheon
- Korea
- Suncheon Research Center for Natural Medicines
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138
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Bekaert M, Verhelst X, Geerts A, Lapauw B, Calders P. Association of recently described adipokines with liver histology in biopsy-proven non-alcoholic fatty liver disease: a systematic review. Obes Rev 2016; 17:68-80. [PMID: 26597657 DOI: 10.1111/obr.12333] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Accepted: 09/11/2015] [Indexed: 12/25/2022]
Abstract
The prevalence of non-alcoholic fatty liver disease (NAFLD) is rising, as is the prevalence of obesity and type 2 diabetes. It is increasingly recognized that an impaired pattern in adipokine secretion could play a pivotal role in the development of NAFLD. We performed a systematic review to evaluate the potential link between newly described adipokines and liver histology in biopsy-proven NAFLD patients. A computerized literature search was performed in PubMed, EMBASE and Web of Science electronic databases. Thirty-one cross-sectional studies were included, resulting in a total of seven different investigated adipokines. Studies included in this review mainly had a good methodological quality. Most adipokines were suggested to be involved in the inflammatory response that develops within the context of NAFLD, either at hepatic or systemic level, and/or hepatic insulin resistance. Based on literature, clinical studies suggest that chemerin, resistin and adipocyte-fatty-acid-binding protein potentially are involved in NAFLD pathogenesis and/or progression. However, major inconsistency still exists, and there is a high need for larger studies, together with the need of standardized assays to determine adipokine levels.
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Affiliation(s)
- M Bekaert
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - X Verhelst
- Department of Gastroenterology and Hepatology, Ghent University Hospital, Ghent, Belgium
| | - A Geerts
- Department of Gastroenterology and Hepatology, Ghent University Hospital, Ghent, Belgium
| | - B Lapauw
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - P Calders
- Revalidation Science and Physiotherapy, Ghent University Hospital, Ghent, Belgium
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139
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Traditional Chinese Medicine: Salvia miltiorrhiza Enhances Survival Rate of Autologous Adipose Tissue Transplantation in Rabbit Model. Aesthetic Plast Surg 2015; 39:985-91. [PMID: 26446419 DOI: 10.1007/s00266-015-0566-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/17/2015] [Indexed: 12/11/2022]
Abstract
OBJECTIVE This study aimed to explore the influence of traditional Chinese medicines: Salvia miltiorrhiza on the survival of auto-transplantation of adipose tissue in a rabbit model. METHODS Minced adipose tissue harvested from the scapular region was transplanted into the dorsum of the ears of New Zealand rabbits. The experimental groups were intra-peritoneally injected with S. miltiorrhiza for a total 4 weeks. The rabbits in control group were intra-peritoneally injected with normal saline. Plasma VEGF levels were assayed at week 1, 2, 4, 6, and 8 after fat tissue auto-transplantation in the dorsum of rabbit ears. Graft samples were collected and measured at week 2, 4, and 12. Survival rates were calculated, and histologic morphology was evaluated. The expression of CD31 was detected by means of immune-histochemical staining to observe neo-vascularization of the auto-transplanted fat tissue. Perilipin was detected by means of immune-histochemical staining to observe the survival of fat cells. RESULTS At 12 weeks, the survival rates in the experimental group were statistically greater than that in the control group, respectively (p < 0.05). Plasma levels of VEGF in the experimental group at different time points were significantly higher than that in the control group (p < 0.05). Histologically, grafts in the experimental group showed better survival of adipocytes and neo-vascularization. By perilipin immuno-histochemical staining, the experimental group demonstrated better adipocyte survival. CONCLUSIONS In the rabbit model, S. miltiorrhiza can promote the neo-vascularization of adipose tissue grafts and significantly improves the survival rate of auto-transplanted adipose tissue. NO LEVEL ASSIGNED This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
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140
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Montes R, Guruceaga E, González-Porras JR, Reverter JC, Marco P, Pina E, Páramo JA, Hermida J, Lecumberri R. Identification of new markers of recurrence in patients with unprovoked deep vein thrombosis by gene expression profiling: the retro study. Eur J Haematol 2015; 97:128-36. [PMID: 26505263 DOI: 10.1111/ejh.12692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2015] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of this study was to assess differences in the gene expression profile of peripheral blood cells between patients with early recurrent thrombosis vs. patients without recurrent events after withdrawal of anticoagulant therapy for a first episode of unprovoked deep vein thrombosis (uDVT), to identify novel predictors of recurrence. METHODS In the discovery population (N = 32), a microarray RNA assay followed by RT-PCR confirmation were performed. In the validation population (N = 44) a multiple RT-PCR-based strategy was applied to assess genes differentially expressed in the discovery population. RESULTS The sex-adjusted Linear Model for Microarray Data analysis showed 102 genes differentially expressed (P < 0.01) in the discovery population. Nineteen of them underwent further confirmation in the validation population. The gene encoding for Acyl-CoA Synthetase Family Member 2 (ACSF2) was underexpressed in recurrent DVT patients in both, the discovery (P = 0.007) and validation populations (P = 0.004). In the receiver operator characteristic (ROC) analysis, the areas under the curve of ACSF2 expression were 0.77 and 0.80, respectively. CONCLUSIONS For the first time an association between ACSF2 expression and the risk of recurrent DVT is suggested. Should this association be confirmed in larger prospective studies, ACSF2 could become useful for the selection of patients requiring extended anticoagulant therapy.
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Affiliation(s)
- Ramón Montes
- Division of Cardiovascular Sciences, Centro de Investigación Médica Aplicada, Pamplona, Spain
| | - Elisabet Guruceaga
- Bioinformatics Unit, Centro de Investigación Médica Aplicada, Pamplona, Spain
| | | | - Joan C Reverter
- Department of Haemotherapy and Haemostasis, Hospital Clinic, Barcelona, Spain
| | - Pascual Marco
- Hematology Service, Hospital General Universitario de Alicante, Alicante, Spain
| | - Elena Pina
- Thrombosis and Haemostasis Unit, Hospital Universitari Bellvitge, Hospitalet de Llobregat, Pamplona, Spain
| | - José A Páramo
- Hematology Service, University Clinic of Navarra, Pamplona, Spain
| | - José Hermida
- Division of Cardiovascular Sciences, Centro de Investigación Médica Aplicada, Pamplona, Spain
| | - Ramón Lecumberri
- Hematology Service, University Clinic of Navarra, Pamplona, Spain
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141
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Hu B, Guo Y, Garbacz WG, Jiang M, Xu M, Huang H, Tsung A, Billiar TR, Ramakrishnan SK, Shah YM, Lam KSL, Huang M, Xie W. Fatty acid binding protein-4 (FABP4) is a hypoxia inducible gene that sensitizes mice to liver ischemia/reperfusion injury. J Hepatol 2015; 63:855-62. [PMID: 26070408 PMCID: PMC4867094 DOI: 10.1016/j.jhep.2015.05.030] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 04/28/2015] [Accepted: 05/21/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Fatty acid binding protein 4 (FABP4) has been known as a mediator of inflammatory response in the macrophages and adipose tissue, but its hepatic function is poorly understood. The goal of this study is to investigate the role of FABP4 in liver ischemia/reperfusion (I/R), a clinical condition that involves both hypoxia and inflammation. METHODS To examine the I/R regulation of FABP4, mice were subjected to I/R surgery before being measured for FABP4 gene expression. Both loss-of-function (by using a pharmacological FABP4 inhibitor) and gain-of-function (by adenoviral overexpression of FABP4) were used to determine the functional relevance of FABP4 expression and its regulation during I/R. To determine the hypoxia responsive regulation of FABP4, primary mouse hepatocytes were exposed to hypoxia. The FABP4 gene promoter was cloned and its regulation by hypoxia inducible factor 1α (HIF-1α) was characterized by luciferase reporter gene, electrophoretic mobility shift, and chromatin immunoprecipitation assays. RESULTS We found that the hepatic expression of FABP4 was markedly induced by I/R. At the functional level, pharmacological inhibition of FABP4 alleviated the I/R injury, whereas adenoviral overexpression of FABP4 sensitized mice to I/R injury. We also showed that exposure of primary hepatocytes to hypoxia or transgenic overexpression of HIF-1α in the mouse liver was sufficient to induce the expression of FABP4. Our promoter analysis established FABP4 as a novel transcriptional target of HIF-1α. CONCLUSIONS FABP4 is a hypoxia inducible gene that sensitizes mice to liver I/R injury. FABP4 may represent a novel therapeutic target, and FABP4 inhibitors may be used as therapeutic agents to manage hepatic I/R injury.
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Affiliation(s)
- Bingfang Hu
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China; Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yan Guo
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pathology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wojciech G Garbacz
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mengxi Jiang
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Meishu Xu
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA
| | - Hai Huang
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Allan Tsung
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Timothy R Billiar
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Sadeesh K Ramakrishnan
- Department of Molecular & Integrative Physiology, Department of Internal Medicine, Division of Gastroenterology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Yatrik M Shah
- Department of Molecular & Integrative Physiology, Department of Internal Medicine, Division of Gastroenterology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Karen S L Lam
- Department of Medicine, The University of Hong Kong, Hong Kong, China
| | - Min Huang
- Institute of Clinical Pharmacology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, China.
| | - Wen Xie
- Center for Pharmacogenetics and Department of Pharmaceutical Sciences, University of Pittsburgh, Pittsburgh, PA, USA; Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA.
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142
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Stinkens R, Goossens GH, Jocken JWE, Blaak EE. Targeting fatty acid metabolism to improve glucose metabolism. Obes Rev 2015; 16:715-57. [PMID: 26179344 DOI: 10.1111/obr.12298] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/23/2015] [Accepted: 05/10/2015] [Indexed: 12/15/2022]
Abstract
Disturbances in fatty acid metabolism in adipose tissue, liver, skeletal muscle, gut and pancreas play an important role in the development of insulin resistance, impaired glucose metabolism and type 2 diabetes mellitus. Alterations in diet composition may contribute to prevent and/or reverse these disturbances through modulation of fatty acid metabolism. Besides an increased fat mass, adipose tissue dysfunction, characterized by an altered capacity to store lipids and an altered secretion of adipokines, may result in lipid overflow, systemic inflammation and excessive lipid accumulation in non-adipose tissues like liver, skeletal muscle and the pancreas. These impairments together promote the development of impaired glucose metabolism, insulin resistance and type 2 diabetes mellitus. Furthermore, intrinsic functional impairments in either of these organs may contribute to lipotoxicity and insulin resistance. The present review provides an overview of fatty acid metabolism-related pathways in adipose tissue, liver, skeletal muscle, pancreas and gut, which can be targeted by diet or food components, thereby improving glucose metabolism.
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Affiliation(s)
- R Stinkens
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - G H Goossens
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - J W E Jocken
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - E E Blaak
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center+, Maastricht, The Netherlands
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143
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Molecular mechanisms of fatty liver in obesity. Front Med 2015; 9:275-87. [PMID: 26290284 DOI: 10.1007/s11684-015-0410-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 05/25/2015] [Indexed: 12/17/2022]
Abstract
Nonalcoholic fatty liver disease (NAFLD) covers a spectrum of liver disorders ranging from simple steatosis to advanced pathologies, including nonalcoholic steatohepatitis and cirrhosis. NAFLD significantly contributes to morbidity and mortality in developed societies. Insulin resistance associated with central obesity is the major cause of hepatic steatosis, which is characterized by excessive accumulation of triglyceride-rich lipid droplets in the liver. Accumulating evidence supports that dysregulation of adipose lipolysis and liver de novo lipogenesis (DNL) plays a key role in driving hepatic steatosis. In this work, we reviewed the molecular mechanisms responsible for enhanced adipose lipolysis and increased hepatic DNL that lead to hepatic lipid accumulation in the context of obesity. Delineation of these mechanisms holds promise for developing novel avenues against NAFLD.
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144
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Oropeza D, Jouvet N, Bouyakdan K, Perron G, Ringuette LJ, Philipson LH, Kiss RS, Poitout V, Alquier T, Estall JL. PGC-1 coactivators in β-cells regulate lipid metabolism and are essential for insulin secretion coupled to fatty acids. Mol Metab 2015; 4:811-22. [PMID: 26629405 PMCID: PMC4632114 DOI: 10.1016/j.molmet.2015.08.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 07/30/2015] [Accepted: 08/05/2015] [Indexed: 11/30/2022] Open
Abstract
Objectives Peroxisome proliferator-activated receptor γ coactivator 1 (PPARGCA1, PGC-1) transcriptional coactivators control gene programs important for nutrient metabolism. Islets of type 2 diabetic subjects have reduced PGC-1α expression and this is associated with decreased insulin secretion, yet little is known about why this occurs or what role it plays in the development of diabetes. Our goal was to delineate the role and importance of PGC-1 proteins to β-cell function and energy homeostasis. Methods We investigated how nutrient signals regulate coactivator expression in islets and the metabolic consequences of reduced PGC-1α and PGC-1β in primary and cultured β-cells. Mice with inducible β-cell specific double knockout of Pgc-1α/Pgc-1β (βPgc-1 KO) were created to determine the physiological impact of reduced Pgc1 expression on glucose homeostasis. Results Pgc-1α and Pgc-1β expression was increased in primary mouse and human islets by acute glucose and palmitate exposure. Surprisingly, PGC-1 proteins were dispensable for the maintenance of mitochondrial mass, gene expression, and oxygen consumption in response to glucose in adult β-cells. However, islets and mice with an inducible, β-cell-specific PGC-1 knockout had decreased insulin secretion due in large part to loss of the potentiating effect of fatty acids. Consistent with an essential role for PGC-1 in lipid metabolism, β-cells with reduced PGC-1s accumulated acyl-glycerols and PGC-1s controlled expression of key enzymes in lipolysis and the glycerolipid/free fatty acid cycle. Conclusions These data highlight the importance of PGC-1s in coupling β-cell lipid metabolism to promote efficient insulin secretion. Loss of Pgc-1s in adult β-cells decreases insulin secretion in response to glucose/palmitate. Pgc-1α/β is not required to maintain basal mitochondrial mass or oxidative capacity in mature β-cells. Pgc-1α/β regulates expression of the lipolytic enzymes HSL and ATGL in β-cells. Reduced β-cell Pgc-1 causes accumulation of intracellular acyl-glycerols and cholesterol esters.
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Affiliation(s)
- Daniel Oropeza
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Nathalie Jouvet
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Khalil Bouyakdan
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Gabrielle Perron
- Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Lea-Jeanne Ringuette
- Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada
| | - Louis H Philipson
- Department of Medicine, University of Chicago, 5801 South Ellis Avenue, Chicago, IL, USA
| | - Robert S Kiss
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Vincent Poitout
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Thierry Alquier
- Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
| | - Jennifer L Estall
- Laboratory of Molecular Mechanisms of Diabetes, Institut de Recherches Cliniques de Montreal (IRCM), 110 Ave des Pins Ouest, Montreal, Quebec, H2W 1R7, Canada ; Department of Anatomy and Cell Biology, McGill University, 845 Rue Sherbrooke Ouest, Montreal, Quebec, H3A 0G4, Canada ; Montreal Diabetes Research Center, CRCHUM, Department of Medicine, University of Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, H3T 1J4, Canada
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145
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Osawa K, Miyoshi T, Yamauchi K, Koyama Y, Nakamura K, Sato S, Kanazawa S, Ito H. Nonalcoholic Hepatic Steatosis Is a Strong Predictor of High-Risk Coronary-Artery Plaques as Determined by Multidetector CT. PLoS One 2015; 10:e0131138. [PMID: 26125952 PMCID: PMC4488355 DOI: 10.1371/journal.pone.0131138] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Accepted: 05/27/2015] [Indexed: 02/06/2023] Open
Abstract
Background Nonalcoholic fatty liver disease is associated with a risk of coronary artery disease (e.g., diabetes mellitus, dyslipidemia, metabolic syndrome). We evaluated whether nonalcoholic hepatic steatosis is associated with high-risk plaques as assessed by multidetector computed tomography (CT). Methods This retrospective study involved 414 participants suspected of having coronary artery disease. Nonalcoholic hepatic steatosis was defined as a liver-to-spleen fat ratio of <1.0 and the presence and appropriate characteristics of coronary-artery plaques as assessed by coronary CT angiography. High-risk plaques were identified, as were low-density plaques, positive remodeling, and spotty calcification. Results Compared with patients who did not have nonalcoholic hepatic steatosis, patients with nonalcoholic hepatic steatosis had more low-density plaques (21% vs. 44%, p<0.01), positive remodeling (41% vs. 58%, p = 0.01), and spotty calcification (12% vs. 36%, p<0.01). The number of high-risk plaques in patients with nonalcoholic hepatic steatosis was greater than in those without nonalcoholic hepatic steatosis (p<0.01). Patients with nonalcoholic hepatic steatosis were more likely to have high-risk plaques than were those with only an elevated level of visceral adipose tissue (≥86 cm2; 35% vs. 16%, p<0.01). Multivariate analyses that included nonalcoholic hepatic steatosis, amount of visceral adipose tissue, and the presence/absence of traditional risk factors demonstrated that nonalcoholic hepatic steatosis was an independent predictor of high-risk plaques (odds ratio: 4.60; 95% confidence interval: 1.94–9.07, p<0.01). Conclusions Diagnosis of nonalcoholic hepatic steatosis may be of value when assessing the risk of coronary artery disease.
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Affiliation(s)
- Kazuhiro Osawa
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Toru Miyoshi
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
- * E-mail:
| | - Kentarou Yamauchi
- Department of Radiology, Okayama University Hospital, Okayama, Japan
| | - Yasushi Koyama
- Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan
| | - Kazufumi Nakamura
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Shuhei Sato
- Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Susumu Kanazawa
- Department of Radiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Hiroshi Ito
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
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146
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Fabbrini E, Magkos F. Hepatic Steatosis as a Marker of Metabolic Dysfunction. Nutrients 2015; 7:4995-5019. [PMID: 26102213 PMCID: PMC4488828 DOI: 10.3390/nu7064995] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 06/05/2015] [Accepted: 06/15/2015] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is the liver manifestation of the complex metabolic derangements associated with obesity. NAFLD is characterized by excessive deposition of fat in the liver (steatosis) and develops when hepatic fatty acid availability from plasma and de novo synthesis exceeds hepatic fatty acid disposal by oxidation and triglyceride export. Hepatic steatosis is therefore the biochemical result of an imbalance between complex pathways of lipid metabolism, and is associated with an array of adverse changes in glucose, fatty acid, and lipoprotein metabolism across all tissues of the body. Intrahepatic triglyceride (IHTG) content is therefore a very good marker (and in some cases may be the cause) of the presence and the degree of multiple-organ metabolic dysfunction. These metabolic abnormalities are likely responsible for many cardiometabolic risk factors associated with NAFLD, such as insulin resistance, type 2 diabetes mellitus, and dyslipidemia. Understanding the factors involved in the pathogenesis and pathophysiology of NAFLD will lead to a better understanding of the mechanisms responsible for the metabolic complications of obesity, and hopefully to the discovery of novel effective treatments for their reversal.
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Affiliation(s)
- Elisa Fabbrini
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Faidon Magkos
- Center for Human Nutrition and Atkins Center of Excellence in Obesity Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA.
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147
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Steneberg P, Sykaras AG, Backlund F, Straseviciene J, Söderström I, Edlund H. Hyperinsulinemia Enhances Hepatic Expression of the Fatty Acid Transporter Cd36 and Provokes Hepatosteatosis and Hepatic Insulin Resistance. J Biol Chem 2015; 290:19034-43. [PMID: 26085100 PMCID: PMC4521028 DOI: 10.1074/jbc.m115.640292] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Indexed: 01/01/2023] Open
Abstract
Hepatosteatosis is associated with the development of both hepatic insulin resistance and Type 2 diabetes. Hepatic expression of Cd36, a fatty acid transporter, is enhanced in obese and diabetic murine models and human nonalcoholic fatty liver disease, and thus it correlates with hyperinsulinemia, steatosis, and insulin resistance. Here, we have explored the effect of hyperinsulinemia on hepatic Cd36 expression, development of hepatosteatosis, insulin resistance, and dysglycemia. A 3-week sucrose-enriched diet was sufficient to provoke hyperinsulinemia, hepatosteatosis, hepatic insulin resistance, and dysglycemia in CBA/J mice. The development of hepatic steatosis and insulin resistance in CBA/J mice on a sucrose-enriched diet was paralleled by increased hepatic expression of the transcription factor Pparγ and its target gene Cd36 whereas that of genes implicated in lipogenesis, fatty acid oxidation, and VLDL secretion was unaltered. Additionally, we demonstrate that insulin, in a Pparγ-dependent manner, is sufficient to directly increase Cd36 expression in perfused livers and isolated hepatocytes. Mouse strains that display low insulin levels, i.e. C57BL6/J, and/or lack hepatic Pparγ, i.e. C3H/HeN, do not develop hepatic steatosis, insulin resistance, or dysglycemia on a sucrose-enriched diet, suggesting that elevated insulin levels, via enhanced CD36 expression, provoke fatty liver development that in turn leads to hepatic insulin resistance and dysglycemia. Thus, our data provide evidence for a direct role for hyperinsulinemia in stimulating hepatic Cd36 expression and thus the development of hepatosteatosis, hepatic insulin resistance, and dysglycemia.
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Affiliation(s)
| | | | | | | | - Ingegerd Söderström
- the Department of Public Health and Clinical Medicine, Umeå University, SE-901 87 Umeå, Sweden
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148
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Berlanga A, Guiu-Jurado E, Porras JA, Aragonès G, Auguet T. [Role of metabolic lipases and lipotoxicity in the development of non-alcoholic steatosis and non-alcoholic steatohepatitis]. CLINICA E INVESTIGACION EN ARTERIOSCLEROSIS 2015; 28:47-61. [PMID: 26049666 DOI: 10.1016/j.arteri.2015.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 10/23/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) has become the most common liver disease in developed countries, covering a spectrum of pathological conditions ranging from single steatosis to non-alcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma. Its pathogenesis has been often interpreted by the "double-hit" hypothesis, where the lipid accumulation in the liver is followed by proinflammatory mediators inducing inflammation, hepatocellular injury and fibrosis. Nowadays, a more complex model suggests that free fatty acids and their metabolites could be the true lipotoxic agents that contribute to the development of NAFLD and hepatic insulin resistance, suggesting a central role for metabolic lipases in that process.
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Affiliation(s)
- Alba Berlanga
- Grupo de recerca GEMMAIR (AGAUR)-Medicina Aplicada, Departamento de Medicina y Cirugía, Universidad Rovira i Virgili (URV), Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, España
| | - Esther Guiu-Jurado
- Grupo de recerca GEMMAIR (AGAUR)-Medicina Aplicada, Departamento de Medicina y Cirugía, Universidad Rovira i Virgili (URV), Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, España
| | - José Antonio Porras
- Grupo de recerca GEMMAIR (AGAUR)-Medicina Aplicada, Departamento de Medicina y Cirugía, Universidad Rovira i Virgili (URV), Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, España; Servicio de Medicina Interna, Hospital Universitario Joan XXIII, Tarragona, España
| | - Gemma Aragonès
- Grupo de recerca GEMMAIR (AGAUR)-Medicina Aplicada, Departamento de Medicina y Cirugía, Universidad Rovira i Virgili (URV), Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, España
| | - Teresa Auguet
- Grupo de recerca GEMMAIR (AGAUR)-Medicina Aplicada, Departamento de Medicina y Cirugía, Universidad Rovira i Virgili (URV), Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, España; Servicio de Medicina Interna, Hospital Universitario Joan XXIII, Tarragona, España.
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149
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Jia C, Huan Y, Liu S, Hou S, Sun S, Li C, Liu Q, Jiang Q, Wang Y, Shen Z. Effect of Chronic Pioglitazone Treatment on Hepatic Gene Expression Profile in Obese C57BL/6J Mice. Int J Mol Sci 2015; 16:12213-29. [PMID: 26035752 PMCID: PMC4490440 DOI: 10.3390/ijms160612213] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 01/07/2023] Open
Abstract
Pioglitazone, a selective ligand of peroxisome proliferator-activated receptor gamma (PPARγ), is an insulin sensitizer drug that is being used in a number of insulin-resistant conditions, including non-alcoholic fatty liver disease (NAFLD). However, there is a discrepancy between preclinical and clinical data in the literature and the benefits of pioglitazone treatment as well as the precise mechanism of action remain unclear. In the present study, we determined the effect of chronic pioglitazone treatment on hepatic gene expression profile in diet-induced obesity (DIO) C57BL/6J mice in order to understand the mechanisms of NAFLD induced by PPARγ agonists. DIO mice were treated with pioglitazone (25 mg/kg/day) for 38 days, the gene expression profile in liver was evaluated using Affymetrix Mouse GeneChip 1.0 ST array. Pioglitazone treatment resulted in exacerbated hepatic steatosis and increased hepatic triglyceride and free fatty acids concentrations, though significantly increased the glucose infusion rate in hyperinsulinemic-euglycemic clamp test. The differentially expressed genes in liver of pioglitazone treated vs. untreated mice include 260 upregulated and 86 downregulated genes. Gene Ontology based enrichment analysis suggests that inflammation response is transcriptionally downregulated, while lipid metabolism is transcriptionally upregulated. This may underlie the observed aggravating liver steatosis and ameliorated systemic insulin resistance in DIO mice.
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Affiliation(s)
- Chunming Jia
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Yi Huan
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Shuainan Liu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Shaocong Hou
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Sujuan Sun
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Caina Li
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Quan Liu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Qian Jiang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Yue Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
| | - Zhufang Shen
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China.
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150
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Fu X, Dong B, Tian Y, Lefebvre P, Meng Z, Wang X, Pattou F, Han W, Wang X, Lou F, Jove R, Staels B, Moore DD, Huang W. MicroRNA-26a regulates insulin sensitivity and metabolism of glucose and lipids. J Clin Invest 2015; 125:2497-509. [PMID: 25961460 DOI: 10.1172/jci75438] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 04/07/2015] [Indexed: 12/15/2022] Open
Abstract
Type 2 diabetes (T2D) is characterized by insulin resistance and increased hepatic glucose production, yet the molecular mechanisms underlying these abnormalities are poorly understood. MicroRNAs (miRs) are a class of small, noncoding RNAs that have been implicated in the regulation of human diseases, including T2D. miR-26a is known to play a critical role in tumorigenesis; however, its function in cellular metabolism remains unknown. Here, we determined that miR-26a regulates insulin signaling and metabolism of glucose and lipids. Compared with lean individuals, overweight humans had decreased expression of miR-26a in the liver. Moreover, miR-26 was downregulated in 2 obese mouse models compared with control animals. Global or liver-specific overexpression of miR-26a in mice fed a high-fat diet improved insulin sensitivity, decreased hepatic glucose production, and decreased fatty acid synthesis, thereby preventing obesity-induced metabolic complications. Conversely, silencing of endogenous miR-26a in conventional diet-fed mice impaired insulin sensitivity, enhanced glucose production, and increased fatty acid synthesis. miR-26a targeted several key regulators of hepatic metabolism and insulin signaling. These findings reveal miR-26a as a regulator of liver metabolism and suggest miR-26a should be further explored as a potential target for the treatment of T2D.
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