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Kurosaka Y, Machida S, Shiroya Y, Yamauchi H, Minato K. Protective Effects of Voluntary Exercise on Hepatic Fat Accumulation Induced by Dietary Restriction in Zucker Fatty Rats. Int J Mol Sci 2021; 22:2014. [PMID: 33670590 PMCID: PMC7922922 DOI: 10.3390/ijms22042014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 12/11/2022] Open
Abstract
Weight control based on dietary restriction (DR) alone can cause lipid metabolic failure and progression to fatty liver. This study aimed to investigate the effect of exercise on preventing DR-induced hepatic fat accumulation in Zucker fatty (ZF) rats by focusing on the relationship between adipose tissue lipolysis and hepatic fat uptake. Six-week-old male ZF rats were randomly assigned to obese, DR, or DR with exercise (DR + Ex) groups. The DR and DR + Ex groups were fed a restricted diet, with the latter also undergoing voluntary exercise. After 6 weeks, hepatic fat accumulation was observed in the DR group, whereas intrahepatic fat was markedly reduced in the DR + Ex group. Compared with the obese (Ob) group, the DR group exhibited 2.09-fold expression of hepatic fatty acid translocase (FAT)/CD36 proteins (p < 0.01) and 0.14-fold expression of hepatic fatty acid-binding protein (FABP)1 (p < 0.01). There were no significant differences between the DR + Ex group and the Ob group. FAT/CD36 and hepatic triglyceride (TG) expression levels were strongly positively correlated (r = 0.81, p < 0.001), whereas there was a strong negative correlation between FABP1 and hepatic TG expression levels (r = -0.65, p < 0.001). Our results suggest that hepatic fat accumulation induced by DR in ZF rats might be prevented through exercise-induced modifications in FAT/CD36 and FABP1 expression.
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Affiliation(s)
- Yuka Kurosaka
- Faculty of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Shuichi Machida
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan;
| | - Yoko Shiroya
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Hideki Yamauchi
- Department of Molecular Physiology, Division of Physical Fitness, The Jikei University School of Medicine, Tokyo 182-8570, Japan;
| | - Kumiko Minato
- Exercise Physiology Laboratory, Wayo Women’s University, Chiba 272-8533, Japan; (Y.S.); (K.M.)
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Lepionka T, Białek M, Czauderna M, Białek A. Pomegranate seed oil and bitter melon extract supplemented in diet influence the lipid profile and intensity of peroxidation in livers of SPRD rats exposed to a chemical carcinogen. Prostaglandins Other Lipid Mediat 2021; 152:106495. [PMID: 33045366 DOI: 10.1016/j.prostaglandins.2020.106495] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 12/21/2022]
Abstract
Despite promising health effects of pomegranate seed oil (PSO) and bitter melon extract (BM) used for centuries as food and traditional medicine, neither mechanism of action nor safety has been fully recognized. This study aimed to evaluate the influence of diet supplementation with PSO and BM on fatty acid, conjugated fatty acid and cholesterol content in rat' livers, since liver is crucial for lipid metabolism. Oxidation indicators (malondialdehyde, oxysterols and tocopherols) were also determined. Lipid profiles did not reveal the presence of punicic acid, while other conjugated dienes and trienes, including rumenic acid, were determined. Both supplementation and exposition to carcinogen significantly increased cholesterol and reduced selected oxysterols levels, simultaneously increasing malondialdehyde content in animals suffering from cancer. Impact of PSO and BM on oxidative status varied depending on carcinogen exposure and coexisting neoplastic process, which is important, due to the growing interest in their use in prevention and therapy of various diseases, including cancer.
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Affiliation(s)
- Tomasz Lepionka
- The Biological Threats Identification and Countermeasure Center of the General Karol Kaczkowski Military Institute of Hygiene and Epidemiology, Lubelska 4 St, 24-100 Puławy, Poland; Department of Bromatology, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland
| | - Małgorzata Białek
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland
| | - Marian Czauderna
- The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland
| | - Agnieszka Białek
- Department of Bromatology, Medical University of Warsaw, Banacha 1, 02-097 Warsaw, Poland; Department of Biotechnology and Nutrigenomics, Institute of Genetics and Animal Biotechnology of Polish Academy of Sciences, Postępu 36A Jastrzębiec, 05-552 Magdalenka, Poland.
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Lambruschini C, Demori I, El Rashed Z, Rovegno L, Canessa E, Cortese K, Grasselli E, Moni L. Synthesis, Photoisomerization, Antioxidant Activity, and Lipid-Lowering Effect of Ferulic Acid and Feruloyl Amides. Molecules 2020; 26:molecules26010089. [PMID: 33379170 PMCID: PMC7794914 DOI: 10.3390/molecules26010089] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 12/23/2020] [Accepted: 12/24/2020] [Indexed: 01/04/2023] Open
Abstract
The Ugi four-component reaction employing naturally occurred ferulic acid (FA) is proposed as a convenient method to synthesize feruloyl tertiary amides. Applying this strategy, a peptoid-like derivative of ferulic acid (FEF77) containing 2 additional hydroxy-substituted aryl groups, has been synthesized. The influence of the configuration of the double bond of ferulic acid and feruloyl amide on the antioxidant activity has been investigated thanks to light-mediated isomerization studies. At the cellular level, both FA, trans and cis isomers of FEF77 were able to protect human endothelial cord vein (HECV) cells from the oxidative damage induced by exposure to hydrogen peroxide, as measured by cell viability and ROS production assays. Moreover, in steatotic FaO rat hepatoma cells, an in vitro model resembling non-alcoholic fatty liver disease (NAFLD), the molecules exhibited a lipid-lowering effect, which, along with the antioxidant properties, points to consider feruloyl amides for further investigations in a therapeutic perspective.
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Affiliation(s)
- Chiara Lambruschini
- Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genova, Italy;
| | - Ilaria Demori
- Department of Earth, Environment and Life Science, University of Genoa, Corso Europa 26, 16132 Genova, Italy; (I.D.); (Z.E.R.); (L.R.)
| | - Zeinab El Rashed
- Department of Earth, Environment and Life Science, University of Genoa, Corso Europa 26, 16132 Genova, Italy; (I.D.); (Z.E.R.); (L.R.)
- Rammal Rammal Laboratory (ATAC Group), Faculty of Sciences I, Lebanese University, Beirut 1003, Lebanon
| | - Leila Rovegno
- Department of Earth, Environment and Life Science, University of Genoa, Corso Europa 26, 16132 Genova, Italy; (I.D.); (Z.E.R.); (L.R.)
| | - Elena Canessa
- MICAMO Spin-Off Department of Earth Sciences, University of Genoa, Corso Europa 26, 16132 Genova, Italy;
| | - Katia Cortese
- DIMES, Department of Experimental Medicine, University of Genoa, Via Antonio de Toni 14, 16132 Genova, Italy;
| | - Elena Grasselli
- Department of Earth, Environment and Life Science, University of Genoa, Corso Europa 26, 16132 Genova, Italy; (I.D.); (Z.E.R.); (L.R.)
- Correspondence: (E.G.); (L.M.); Tel.: +39-010-353-38257 (E.G. & L.M.)
| | - Lisa Moni
- Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genova, Italy;
- Correspondence: (E.G.); (L.M.); Tel.: +39-010-353-38257 (E.G. & L.M.)
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Lu S, Ma Z, Gu Y, Li P, Chen Y, Bai M, Zhou H, Yang X, Jiang H. Downregulation of glucose‐6‐phosphatase expression contributes to fluoxetine‐induced hepatic steatosis. J Appl Toxicol 2020; 41:1232-1240. [PMID: 33179799 DOI: 10.1002/jat.4109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/21/2020] [Accepted: 10/26/2020] [Indexed: 12/21/2022]
Affiliation(s)
- Shuanghui Lu
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
| | - Zhiyuan Ma
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
- Affiliated Hangzhou First People's Hospital, College of Medicine Zhejiang University Hangzhou China
| | - Yong Gu
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
| | - Ping Li
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
| | - Yingchun Chen
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
| | - Mengru Bai
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
- Affiliated Hangzhou First People's Hospital, College of Medicine Zhejiang University Hangzhou China
| | - Hui Zhou
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
| | - Xi Yang
- The First Affiliated Hospital, College of Medicine Zhejiang University Hangzhou China
| | - Huidi Jiang
- Institute of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences Zhejiang University Hangzhou China
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Zhang AR, Sun J, He Y, Wang N, Tian L. Attenuation of lipid accumulation in Bel-7402 cells through ADPN/AMPKα signaling stimulated by Fructus rosae laxae extract. J Food Biochem 2020; 44:e13497. [PMID: 33029846 DOI: 10.1111/jfbc.13497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 09/05/2020] [Accepted: 09/09/2020] [Indexed: 12/29/2022]
Abstract
In this work, a comparison study was conducted on the contents of total flavonoids and hyperoside in different polarity extracts of Fructus rosae laxae (FRL). The lipid-lowering effect and mechanism of FRL ethyl acetate extract (FRLE) on the lipid accumulation model of Bel-7402 cells in vitro were studied. The results showed that the contents of total flavonoids and hyperoside in FRLE were significantly higher than those in the other polarity extracts. Compared with those in the model group, the levels of triglyceride and total cholesterol decreased, the activities of superoxide dismutase and lactate dehydrogenase increased, and the levels of inflammatory factors interleukin-6 and tumor necrosis factor-α decreased significantly in the cells intervened with FRLE. Moreover, FRLE can regulate lipid metabolism by activating the AMP-activated protein kinase α phosphorylation pathway and increasing the expression of adiponectin. PRACTICAL APPLICATIONS: Fructus rosae laxae (FRL) is an edible medicinal fruit with multiple biological activities, such as antioxidation, anti-inflammatory, and hepatoprotective properties. However, the lipid-lowering activity of FRL and its mechanism of action have not yet been investigated. Our data indicate that the FRL extract, which contains high levels of antioxidant and anti-inflammatory components, plays a beneficial role in regulating lipid metabolism disorders, mainly by regulating the expression of proteins involved in the ADPN/AMPK signaling pathway, and reduces the release of inflammatory factors. Thus, the FRL extract effectively reduces the accumulation of free fatty acids (FFA) in vitro and exhibits considerable potential for the prevention and treatment lipid metabolism disorders.
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Affiliation(s)
- Ai-Rong Zhang
- College of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi, P.R.China
| | - Jing Sun
- College of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi, P.R.China
| | - Yuan He
- College of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi, P.R.China
| | - Ning Wang
- College of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi, P.R.China
| | - Li Tian
- College of Traditional Chinese Medicine, Xinjiang Medical University, Urumqi, P.R.China
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56
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FATP2-targeted therapies - A role beyond fatty liver disease. Pharmacol Res 2020; 161:105228. [PMID: 33027714 DOI: 10.1016/j.phrs.2020.105228] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/26/2020] [Accepted: 09/27/2020] [Indexed: 12/31/2022]
Abstract
Fatty acid transport protein 2 (FATP2) is a multifunctional protein whose specific function is determined by the type of located cell, its intracellular location, or organelle-specific interactions. In the different diseases setting, a newfound appreciation for the biological function of FATP2 has come into view. Two main functions of FATP2 are to activate long-chain fatty acids (LCFAs) as a very long-chain acyl-coenzyme A (CoA) synthetase (ACSVL) and to transport LCFAs as a fatty acid transporter. FATP2 is not only involved in the occurrence of nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM), but also plays an important role in lithogenic diet-induced cholelithiasis, the formation of cancer tumor immunity, the progression of chronic kidney disease (CKD), and the regulation of zoledronate-induced nephrotoxicity. Herein, we review the updated information on the role of FATP2 in related diseases. In particular, we discuss the new functions of FATP2 and propose that FATP2 is a potential clinical biomarker and therapeutic target. In conclusion, regulatory strategies for FATP2 may bring new treatment options for cancer and lipid metabolism-related disorders.
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57
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High fat diet-triggered non-alcoholic fatty liver disease: A review of proposed mechanisms. Chem Biol Interact 2020; 330:109199. [DOI: 10.1016/j.cbi.2020.109199] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 02/07/2023]
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58
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Liu Y, Li J, Liu Y. Effects of epoxy stearic acid on lipid metabolism in HepG2 cells. J Food Sci 2020; 85:3644-3652. [PMID: 32885409 DOI: 10.1111/1750-3841.15405] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/29/2020] [Accepted: 07/10/2020] [Indexed: 01/09/2023]
Abstract
In the present study, effects of cis-9,10-epoxystearic acid (ESA) generated by the thermal oxidation of oleic acid on HepG2 cells, including intracellular lipid accumulation, fatty acid composition, and lipid metabolism, were investigated. Our results revealed that ESA increased the number and size of cellular lipid droplets. Intracellular triacylglycerol and total cholesterol content demonstrated that ESA induced lipid accumulation in HepG2 cells in a dose- and time-dependent manner. Results of fatty acid composition further indicated that ESA could lead to intracellular lipid accumulation. Our results also revealed that ESA may suppress the fatty acid oxidation in peroxisomes and mitochondria, including PPARα, Cpt1α, and Acox1, whereas the expression of genes involved in lipid synthesis, including Srebp-1c and Scd1, was enhanced. These findings provide critical information on the effects of ESA on HepG2 cells, particularly lipid accumulation and metabolism, which is important for evaluating the biosafety of the oxidative product of oleic acid. PRACTICAL APPLICATION: The administration of cis-9,10-epoxystearic acid to HepG2 cells could lead to disorder of lipid metabolism of cells by enhancing the intracellular lipid content, as well as suppressing the fatty acid oxidation in peroxisomes and mitochondria. These findings could provide information for the evaluation of the biosafety of the oxidative product of oleic acid.
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Affiliation(s)
- Ying Liu
- School of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, People's Republic of China
| | - Jinwei Li
- School of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, People's Republic of China
| | - Yuanfa Liu
- School of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu Province, 214122, People's Republic of China
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Giammanco M, Di Liegro CM, Schiera G, Di Liegro I. Genomic and Non-Genomic Mechanisms of Action of Thyroid Hormones and Their Catabolite 3,5-Diiodo-L-Thyronine in Mammals. Int J Mol Sci 2020; 21:ijms21114140. [PMID: 32532017 PMCID: PMC7312989 DOI: 10.3390/ijms21114140] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 06/05/2020] [Accepted: 06/08/2020] [Indexed: 02/06/2023] Open
Abstract
Since the realization that the cellular homologs of a gene found in the retrovirus that contributes to erythroblastosis in birds (v-erbA), i.e. the proto-oncogene c-erbA encodes the nuclear receptors for thyroid hormones (THs), most of the interest for THs focalized on their ability to control gene transcription. It was found, indeed, that, by regulating gene expression in many tissues, these hormones could mediate critical events both in development and in adult organisms. Among their effects, much attention was given to their ability to increase energy expenditure, and they were early proposed as anti-obesity drugs. However, their clinical use has been strongly challenged by the concomitant onset of toxic effects, especially on the heart. Notably, it has been clearly demonstrated that, besides their direct action on transcription (genomic effects), THs also have non-genomic effects, mediated by cell membrane and/or mitochondrial binding sites, and sometimes triggered by their endogenous catabolites. Among these latter molecules, 3,5-diiodo-L-thyronine (3,5-T2) has been attracting increasing interest because some of its metabolic effects are similar to those induced by T3, but it seems to be safer. The main target of 3,5-T2 appears to be the mitochondria, and it has been hypothesized that, by acting mainly on mitochondrial function and oxidative stress, 3,5-T2 might prevent and revert tissue damages and hepatic steatosis induced by a hyper-lipid diet, while concomitantly reducing the circulating levels of low density lipoproteins (LDL) and triglycerides. Besides a summary concerning general metabolism of THs, as well as their genomic and non-genomic effects, herein we will discuss resistance to THs and the possible mechanisms of action of 3,5-T2, also in relation to its possible clinical use as a drug.
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Affiliation(s)
- Marco Giammanco
- Department of Surgical, Oncological and Oral Sciences (Discipline Chirurgiche, Oncologiche e Stomatologiche), University of Palermo, 90127 Palermo, Italy;
| | - Carlo Maria Di Liegro
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)), University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Gabriella Schiera
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF)), University of Palermo, 90128 Palermo, Italy; (C.M.D.L.); (G.S.)
| | - Italia Di Liegro
- Department of Biomedicine, Neurosciences and Advanced Diagnostics (Dipartimento di Biomedicina, Neuroscienze e Diagnostica avanzata (Bi.N.D.)), University of Palermo, 90127 Palermo, Italy
- Correspondence: ; Tel.: +39-091-2389-7415 or +39-091-2389-7446
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Park WJ, Song JH, Kim GT, Park TS. Ceramide and Sphingosine 1-Phosphate in Liver Diseases. Mol Cells 2020; 43:419-430. [PMID: 32392908 PMCID: PMC7264474 DOI: 10.14348/molcells.2020.0054] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/06/2020] [Accepted: 04/19/2020] [Indexed: 12/12/2022] Open
Abstract
The liver is an important organ in the regulation of glucose and lipid metabolism. It is responsible for systemic energy homeostasis. When energy need exceeds the storage capacity in the liver, fatty acids are shunted into nonoxidative sphingolipid biosynthesis, which increases the level of cellular ceramides. Accumulation of ceramides alters substrate utilization from glucose to lipids, activates triglyceride storage, and results in the development of both insulin resistance and hepatosteatosis, increasing the likelihood of major metabolic diseases. Another sphingolipid metabolite, sphingosine 1-phosphate (S1P) is a bioactive signaling molecule that acts via S1P-specific G protein coupled receptors. It regulates many cellular and physiological events. Since an increase in plasma S1P is associated with obesity, it seems reasonable that recent studies have provided evidence that S1P is linked to lipid pathophysiology, including hepatosteatosis and fibrosis. Herein, we review recent findings on ceramides and S1P in obesity-mediated liver diseases and the therapeutic potential of these sphingolipid metabolites.
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Affiliation(s)
- Woo-Jae Park
- Department of Biochemistry, College of Medicine, Gachon University, Incheon 2999, Korea
| | - Jae-Hwi Song
- Department of Life Science, Gachon University, Seongnam 1310, Korea
| | - Goon-Tae Kim
- Department of Life Science, Gachon University, Seongnam 1310, Korea
| | - Tae-Sik Park
- Department of Life Science, Gachon University, Seongnam 1310, Korea
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Matilainen J, Mustonen AM, Rilla K, Käkelä R, Sihvo SP, Nieminen P. Orotic acid-treated hepatocellular carcinoma cells resist steatosis by modification of fatty acid metabolism. Lipids Health Dis 2020; 19:70. [PMID: 32284043 PMCID: PMC7155272 DOI: 10.1186/s12944-020-01243-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/18/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Orotic acid (OA) has been intensively utilized to induce fatty liver in rats. Although the capacity of OA to cause steatosis is species-specific, previous in vitro studies indicate that humans could also be susceptible to OA-induced fatty liver. The aim of the present study was to re-elucidate the potential of OA exposure to modulate the cellular mechanisms involved in both non-alcoholic fatty liver disease pathogenesis and cellular protection from lipid accumulation. In addition, alterations in detailed fatty acid (FA) profiles of cells and culture media were analyzed to assess the significance of lipid metabolism in these phenomena. METHODS In our experiments, human hepatocellular carcinoma HepG2 cells were exposed to OA. Bacterial endotoxin, lipopolysaccharide (LPS), was used to mimic hepatic inflammation. The lipogenic and inflammatory effects of OA and/or LPS on cells were assessed by labeling cellular lipids with Nile red stain and by performing image quantifications. The expression levels of key enzymes involved in de novo lipogenesis (DNL) and of inflammatory markers related to the disease development were studied by qRT-PCR. FA profiles of cells and culture media were determined from total lipids with gas chromatography-mass spectrometry. RESULTS Our data indicate that although OA possibly promotes the first stage of DNL, it does not cause a definite lipogenic transformation in HepG2 cells. Reduced proportions of 16:0, increased stearoyl-Coenzyme A desaturase 1 mRNA expression and relatively high proportions of 16:1n-7 suggest that active delta9-desaturation may limit lipogenesis and the accumulation of toxic 16:0. Inflammatory signaling could be reduced by the increased production of long-chain n-3 polyunsaturated FA (PUFA) and the active incorporation of certain FA, including 18:1n-9, into cells. In addition, increased proportions of 20:4n-6 and 22:6n-3, total PUFA and dimethyl acetal 18:0 suggest that OA exposure may cause increased secretion of lipoproteins and extracellular vesicles. CONCLUSIONS The present data suggest that, apart from the transcription-level events reported by previous studies, modifications of FA metabolism may also be involved in the prevention of OA-mediated steatosis. Increased delta9-desaturation and secretion of lipoproteins and extracellular vesicles could offer potential mechanisms for further studies to unravel how OA-treated cells alleviate lipidosis.
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Affiliation(s)
- Johanna Matilainen
- Faculty of Health Sciences, School of Medicine, Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland.
| | - Anne-Mari Mustonen
- Faculty of Health Sciences, School of Medicine, Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
- Faculty of Science and Forestry, Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 111, FI-80101, Joensuu, Finland
| | - Kirsi Rilla
- Faculty of Health Sciences, School of Medicine, Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Reijo Käkelä
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Programme, University of Helsinki, P.O. Box 65, FI-00014, Helsinki, Finland
- Helsinki Institute for Life Science (HiLIFE), Helsinki University Lipidomics Unit (HiLIPID), University of Helsinki, P.O. Box 65, FI-00014, Helsinki, Finland
| | - Sanna P Sihvo
- Faculty of Biological and Environmental Sciences, Molecular and Integrative Biosciences Research Programme, University of Helsinki, P.O. Box 65, FI-00014, Helsinki, Finland
- Helsinki Institute for Life Science (HiLIFE), Helsinki University Lipidomics Unit (HiLIPID), University of Helsinki, P.O. Box 65, FI-00014, Helsinki, Finland
| | - Petteri Nieminen
- Faculty of Health Sciences, School of Medicine, Institute of Biomedicine, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
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Kim GT, Kim SJ, Park SH, Lee D, Park TS. Hepatic Expression of the Serine Palmitoyltransferase Subunit Sptlc2 Reduces Lipid Droplets in the Liver by Activating VLDL Secretion. J Lipid Atheroscler 2020; 9:291-303. [PMID: 32821738 PMCID: PMC7379091 DOI: 10.12997/jla.2020.9.2.291] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Revised: 02/18/2020] [Accepted: 03/03/2020] [Indexed: 01/22/2023] Open
Abstract
Objective Ceramide is a signaling molecule that contributes to insulin resistance and hepatosteatosis. In the present study, we activated de novo ceramide synthesis by inducing the hepatic expression of Sptlc2 to investigate the role of ceramide in glucose and lipid metabolism. Methods We first constructed an adenovirus containing Sptlc2 (AdSptlc2), which encodes a major catalytic subunit of serine palmitoyltransferase (SPT). We then infected hepatocytes and mice fed a regular diet with AdSptlc2 to activate de novo ceramide biosynthesis. The liver-specific effects of ceramide biosynthesis on glucose and lipid metabolism were investigated by measuring changes in insulin signaling, lipid droplet formation, and very low-density lipoprotein (VLDL) secretion. Results In HepG2 hepatocytes, adenoviral Sptlc2 expression inhibited insulin signaling and increased ceramide levels via activation of c-Jun N-terminal kinase and serine phosphorylation of insulin receptor substrate 1. In contrast, in mice, AdSptlc2 infection decreased plasma glucose levels by downregulating gluconeogenic genes and increased plasma triglyceride levels by increasing VLDL secretion. In mice infected with AdSptlc2, glucose intolerance and insulin sensitivity improved, while pyruvate utilization via gluconeogenesis decreased. Conclusion Hepatic ceramide was found to modulate hepatosteatosis and the insulin response via increased VLDL secretion and inhibition of gluconeogenesis in vivo. Although inhibition of the insulin response was observed in vitro, the compensatory mechanism of relieving ceramide-induced stress and reducing ceramide levels resulted in improvements of glucose and lipid metabolic profiles in vivo. This discrepancy between in vitro and in vivo regulation mechanisms suggests that ceramide plays a role in non-alcoholic fatty liver disease and insulin resistance.
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Affiliation(s)
- Goon-Tae Kim
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Su-Jung Kim
- Biomedical Research Center, Asan Institute for Life Sciences, Seoul, Korea
| | - Si-Hyun Park
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Dongyup Lee
- Department of Life Science, Gachon University, Seongnam, Korea
| | - Tae-Sik Park
- Department of Life Science, Gachon University, Seongnam, Korea
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Huang W, Xie P, Cai Z. Lipid metabolism disorders contribute to hepatotoxicity of triclosan in mice. JOURNAL OF HAZARDOUS MATERIALS 2020; 384:121310. [PMID: 31586915 DOI: 10.1016/j.jhazmat.2019.121310] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/13/2019] [Accepted: 09/23/2019] [Indexed: 05/05/2023]
Abstract
Previous in vivo exposure studies focused mainly on nuclear receptors involved in hepatotoxicity of triclosan (TCS). As liver plays a vital role in metabolic processes, dysregulations in lipid metabolism have been identified as potential drivers of pathogenesis. Investigation of changes in lipid metabolism might widen our understanding of toxicological effects as well as the underlying mechanism occurring in the liver. In this study, we comprehensively assessed the effect of TCS exposure on hepatic lipid metabolism in mice. Our results showed that TCS induced significant changes in hepatic free fatty acid pool by upregulation of fatty acid uptake and de novo fatty acid synthesis. Besides, hepatic levels of lipids, including acyl carnitine (AcCa), ceramide (Cer), triacylglycerols (TG), phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylethanolamine (PE) were also increased, together with upreguation of genes associated to TG synthesis, fatty acid oxidation and inflammation in TCS exposure group. These changes in lipid homeostasis could contribute to membrane instability, lipid accumulation, oxidative stress and inflammation. Our results suggested that TCS exposure could induce hepatic lipid metabolism disorders in mice, which would further contribute to the liver damage effects of TCS.
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Affiliation(s)
- Wei Huang
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China; College of Chemistry and Molecular Science, Wuhan University, Hubei, PR China
| | - Peisi Xie
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China
| | - Zongwei Cai
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong Special Administrative Region, PR China.
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Hepatic FATP5 expression is associated with histological progression and loss of hepatic fat in NAFLD patients. J Gastroenterol 2020; 55:227-243. [PMID: 31602526 DOI: 10.1007/s00535-019-01633-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 09/19/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are characterized by the accumulation of excess hepatic fat. However, in the progression from NASH to cirrhosis, hepatic fat is often lost. Our aim was to elucidate the mechanism underlying hepatic fat loss during NASH progression. METHODS Liver biopsies were performed at The University of Tokyo Hospital between November 2011 and March 2016 on 146 patients with NAFLD and 14 patients with cryptogenic cirrhosis who were not being treated with any diabetes or dyslipidemia drugs. Among them, 70 patients underwent liver biopsy after an overnight fast, and 90 patients were biopsied 5 h after an oral glucose tolerance test. Expression differences in genes encoding several fatty acid metabolism-related factors were examined and correlated with hepatic histological changes based on NAFLD activity scores. Prospective patient follow-up continued until June 2018. RESULTS The level of fatty acid transport protein 5 (FATP5), which is associated with free fatty acid intake, was significantly and inversely correlated with features of histological progression, including ballooning and fibrosis. This was confirmed by immunohistochemical analysis. Transcript levels of genes encoding fatty acid metabolism-related proteins were comparable between NASH with severe fibrosis and cryptogenic cirrhosis. Furthermore, a prospective cohort study demonstrated that low FATP5 expression was the most significant risk factor for hepatic fat loss. CONCLUSIONS Decreased hepatic FATP5 expression in NAFLD is linked to histological progression, and may be associated with hepatic fat loss during NASH progression to cirrhosis.
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65
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Xyloglucan affects gut-liver circulating bile acid metabolism to improve liver damage in mice fed with high-fat diet. J Funct Foods 2020. [DOI: 10.1016/j.jff.2019.103651] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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66
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Hepatic gene expression explains primary drug toxicity in bipolar disorder. Transl Psychiatry 2019; 9:331. [PMID: 31819046 PMCID: PMC6901567 DOI: 10.1038/s41398-019-0666-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/23/2019] [Accepted: 11/06/2019] [Indexed: 11/16/2022] Open
Abstract
In bipolar disorder (BPD), long-term psychotropic drug treatment is often necessary to prevent relapse or recurrence. Nevertheless, adverse drug effects including disturbances in hepatic metabolism are observed and still poorly understood. Here, the association between hepatic gene expression and histopathological changes of the liver was investigated. By the use of microarrays (Affymetrix U133 plus2.0), a genome-wide expression study was performed on BPD patients with psychotropic drug treatment (n = 29) compared to unaffected controls (n = 20) and validated by quantitative real-time PCR. WebGestalt was used to identify over-represented functional pathways of the Reactome database. Association analyses between histopathological changes and differentially expressed genes comprised in the over-represented functional pathways were performed using regression analyses, from which feature-expression heatmaps were drawn. The majority of identified genes were underexpressed and involved in energy supply, metabolism of lipids and proteins, and the innate immune system. Positive associations were found for genes involved in all pathways and degenerative changes. The strongest negative association was observed between genes involved in energy supply and hepatic activity, as well as inflammation. In summary, we found a possible association between gene expression involved in various biological pathways and histopathological changes of the liver in BPD. Further, we found support for the probable primary toxic effect of psychotropic drugs on hepatic injury in BPD. Even if the safety of psychotropic drugs improves, adverse effects especially on hepatic function should not be underestimated.
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67
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Yi S, Chen P, Yang L, Zhu L. Probing the hepatotoxicity mechanisms of novel chlorinated polyfluoroalkyl sulfonates to zebrafish larvae: Implication of structural specificity. ENVIRONMENT INTERNATIONAL 2019; 133:105262. [PMID: 31665679 DOI: 10.1016/j.envint.2019.105262] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
Hepatotoxicity in zebrafish (Danio rerio) larvae elicited by legacy perfluorooctane sulfonate (PFOS) and its three novel chlorinated alternatives, including chlorinated polyfluorooctane sulfonate (Cl-PFOS) and chlorinated polyfluoroalkyl ether sulfonates (6:2 and 8:2 Cl-PFESA analogs), was evaluated in this study. Upon 7-day separate exposure to the four target compounds at 1 µmol/L, significant hepatic steatosis in exposed larvae was evidenced by pathological micro/macro vacuolation, which was presumably attributed to the excess accumulation of lipid, especially the overloaded triglyceride (TG) level. Disruption on gene transcription was subjected to a structure-dependent manner. In general, PFOS, Cl-PFOS and 6:2 Cl-PFESA of the identical carbon chain length (i.e. C8), despite with different substituents, displayed a similar activation mode and comparable disruptive potency on lipid metabolism responsive genes, which particularly promoted fatty acid synthesis (acetyl-CoA carboxylase, acacb) and β-oxidation (cytochrome P450 enzymes-1A, cyp1a; peroxisomal acyl-CoA oxidase 1, acox1; and acyl-CoA dehy-drogenase, acadm). However, 8:2 Cl-PFESA with a prolonged carbon chain length (i.e. C10), preferentially disturbed fatty acid exportation (apolipoprotein-B100, apob) and triggered a different modulation pattern on fatty acid β-oxidation against the other three compounds. Molecular docking analysis indicated that 8:2 Cl-PFESA exhibited considerably higher peroxisome proliferator-activated receptors (PPARs) antagonism than others, corresponding to its unique suppression effect on fatty acid β-oxidation responsive genes. To our knowledge, this is the first in vivo study reporting hepatotoxicity of Cl-PFOS and Cl-PFESAs to aquatic organisms. Although characterized with different toxic mode-of-action, these novel alternatives can elicit hepatic steatosis as strong as PFOS, stressing the biological risks in view of their global contamination.
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Affiliation(s)
- Shujun Yi
- State Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Pengyu Chen
- State Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Liping Yang
- State Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Lingyan Zhu
- State Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
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Zhang X, Han Z, Zhong H, Yin Q, Xiao J, Wang F, Zhou Y, Luo Y. Regulation of triglyceride synthesis by estradiol in the livers of hybrid tilapia (Oreochromis niloticus ♀ × O. aureus ♂). Comp Biochem Physiol B Biochem Mol Biol 2019; 238:110335. [DOI: 10.1016/j.cbpb.2019.110335] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/16/2019] [Accepted: 08/27/2019] [Indexed: 02/08/2023]
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Abstract
Pancreatic steatosis is an emerging clinical entity whose pathophysiology, natural history, and long-term complications are poorly characterized in the current literature. Epidemiological and prospective studies have described prevalence rates between 16% and 35%. Although the natural history is not well known, there are strong associations with obesity, metabolic syndrome, type 2 diabetes mellitus, and nonalcoholic fatty liver disease. Ectopic fat accumulation of the pancreas can cause chronic, low-grade inflammation from adipocytokine imbalances that involve beta cells and acinar cells. This mechanism can lead to pancreatic endocrine and exocrine dysfunction and initiate carcinogenesis. Although it is associated with morbid conditions, pancreatic steatosis may be amendable to treatment with a healthy diet, less meat consumption, exercise, and smoking cessation. Pancreatic steatosis should factor into clinical decision-making and prognostication of patients with pancreatic and systemic disease. This review seeks to describe the pathophysiology, natural history, diagnosis, and complications of this emerging clinically relevant entity.
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Potential Therapeutic Application of Estrogen in Gender Disparity of Nonalcoholic Fatty Liver Disease/Nonalcoholic Steatohepatitis. Cells 2019; 8:cells8101259. [PMID: 31619023 PMCID: PMC6835656 DOI: 10.3390/cells8101259] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 10/10/2019] [Accepted: 10/12/2019] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) caused by fat accumulation in the liver is globally the most common cause of chronic liver disease. Simple steatosis can progress to nonalcoholic steatohepatitis (NASH), a more severe form of NAFLD. The most potent driver for NASH is hepatocyte death induced by lipotoxicity, which triggers inflammation and fibrosis, leading to cirrhosis and/or liver cancer. Despite the significant burden of NAFLD, there is no therapy for NAFLD/NASH. Accumulating evidence indicates gender-related NAFLD progression. A higher incidence of NAFLD is found in men and postmenopausal women than premenopausal women, and the experimental results, showing protective actions of estradiol in liver diseases, suggest that estrogen, as the main female hormone, is associated with the progression of NAFLD/NASH. However, the mechanism explaining the functions of estrogen in NAFLD remains unclear because of the lack of reliable animal models for NASH, the imbalance between the sexes in animal experiments, and subsequent insufficient results. Herein, we reviewed the pathogenesis of NAFLD/NASH focused on gender and proposed a feasible association of estradiol with NAFLD/NASH based on the findings reported thus far. This review would help to expand our knowledge of the gender differences in NAFLD and for developing gender-based treatment strategies for NAFLD/NASH.
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Relationship between Muscle Mass/Strength and Hepatic Fat Content in Post-Menopausal Women. ACTA ACUST UNITED AC 2019; 55:medicina55100629. [PMID: 31554294 PMCID: PMC6843176 DOI: 10.3390/medicina55100629] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 12/25/2022]
Abstract
Background and Objectives: Recent studies have shown that low skeletal muscle mass can contribute to non-alcoholic fatty liver disease through insulin resistance. However, the association between muscle mass/strength and hepatic fat content remains unclear in postmenopausal women. Methods: In this study, we assessed the associations between muscle mass/strength and various severities of non-alcoholic fatty liver disease. Using single-voxel proton magnetic resonance spectroscopy, 96 postmenopausal women between the ages of 50 and 65 were divided into four groups (G0–G3) by hepatic fat content: G0 (hepatic fat content <5%, n = 20), G1 (5% ≤ hepatic fat content < 10%, n = 27), G2 (10% ≤ hepatic fat content < 25%, n = 31), and G3 (hepatic fat content ≥25%, n = 18). Muscle mass indexes were estimated as skeletal muscle index (SMI)% (total lean mass/weight × 100) and appendicular skeletal muscular mass index (ASM)% (appendicular lean mass/weight × 100) by dual energy X-ray absorptiometry. Maximal isometric voluntary contraction of the handgrip, elbow flexors, and knee extensors was measured using an adjustable dynamometer chair. Fasting plasma glucose, insulin, and follicle-stimulating hormones were assessed in venous blood samples. Results: The results showed negative correlations between hepatic fat content and SMI% (r = −0.42, p < 0.001), ASM% (r = −0.29, p = 0.005), maximal voluntary force of grip (r = −0.22, p = 0.037), and knee extensors (r = −0.22, p = 0.032). Conclusions: These significant correlations almost remained unchanged even after controlling for insulin resistance. In conclusion, negative correlations exist between muscle mass/strength and the progressed severity of non-alcoholic fatty liver disease among post-menopausal women, and the correlations are independent of insulin resistance.
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Abstract
PURPOSE OF REVIEW Pancreatic steatosis is a clinical entity with emerging significance and impacts patient health in a multitude of ways. It has a high prevalence in the global population with predilections for different demographics by age, sex and ethnicity. Understanding the pathophysiology, clinical features and complications of this entity may be important to understanding the consequences of the ongoing obesity global epidemic. RECENT FINDINGS Obesity and metabolic syndrome contribute to metabolic derangements that result in lipid mishandling by adipocytes. Adipocytokine imbalances in circulation and in the pancreatic microenvironment cause chronic, low-grade inflammation. The resulting beta cell and acinar cell apoptosis leads to pancreatic endocrine and exocrine dysfunction. Furthermore, these adipocytokines regulate cell growth, differentiation, as well as angiogenesis and lymphatic spread. These consequences of adipocyte infiltration are thought to initiate carcinogenesis, leading to pancreatic intraepithelial neoplasia and pancreatic ductal adenocarcinoma. SUMMARY Obesity will lead to millions of deaths each year and pancreatic steatosis may be the key intermediate entity that leads to obesity-related complications. Enhancing our understanding may reveal strategies for preventing mortality and morbidity related to the global epidemic of obesity. Further research is needed to determine the pathophysiology, long-term complications and effective treatment strategies for this condition.
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Propionate suppresses hepatic gluconeogenesis via GPR43/AMPK signaling pathway. Arch Biochem Biophys 2019; 672:108057. [PMID: 31356781 DOI: 10.1016/j.abb.2019.07.022] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/23/2019] [Accepted: 07/25/2019] [Indexed: 12/18/2022]
Abstract
Short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate are generated by gut microbial fermentation of dietary fiber. SCFAs may exert multiple beneficial effects on human lipid and glucose metabolism. However, their actions and underlying mechanisms are not fully elucidated. In this study, we examined the direct effects of propionate on hepatic glucose and lipid metabolism using human HepG2 hepatocytes. Here, we demonstrate that propionate at a physiologically-relevant concentration effectively suppresses palmitate-enhanced glucose production in HepG2 cells but does not affect intracellular neutral lipid levels. Our results indicated that propionate can decline in gluconeogenesis by down-regulation of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) through activation of AMP-activated protein kinase (AMPK), which is a major regulator of the hepatic glucose metabolism. Mechanistic studies also revealed that propionate-stimulated AMPK phosphorylation can be ascribed to Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) activation in response to an increase in intracellular Ca2+ concentration. Moreover, siRNA-mediated knockdown of the propionate receptor GPR43 prevented propionate-inducible activation of AMPK and abrogates the gluconeogenesis-inhibitory action. Thus, our data indicate that the binding of propionate to hepatic GPR43 elicits CaMKKβ-dependent activation of AMPK through intracellular Ca2+ increase, leading to suppression of gluconeogenesis. The present study suggests the potential efficacy of propionate in preventive and therapeutic management of diabetes.
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Tian Y, Shang Y, Guo R, Chang Y, Jiang Y. Salinity stress-induced differentially expressed miRNAs and target genes in sea cucumbers Apostichopus japonicus. Cell Stress Chaperones 2019; 24:719-733. [PMID: 31134533 PMCID: PMC6657415 DOI: 10.1007/s12192-019-00996-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 12/11/2022] Open
Abstract
Environmental salinity is an important abiotic factor influencing normal physiological functions and productive performance in the sea cucumber Apostichopus japonicus. It is therefore important to understand how changes in salinity affect sea cucumbers in the face of global climate change. In this study, we investigated the responses to salinity stress in sea cucumbers using mRNA and miRNA sequencing. The regulatory network of mRNAs and miRNAs involved in salinity stress was examined, and the metabolic pathways enriched for differentially expressed miRNAs and target mRNAs were identified. The top 20 pathways were involved in carbohydrate metabolism, fatty acid metabolism, degradation, and elongation, amino acid metabolism, genetic information processing, metabolism of cofactors and vitamins, transport and catabolism, and environmental information processing. A total of 22 miRNAs showed differential expression during salinity acclimation. The predicted 134 target genes were enriched in functions consistent with the results of gene enrichment based on transcriptome analysis. These results suggested that sea cucumbers deal with salinity stress via changes in amino acid metabolism, ion channels, transporters, and aquaporins, under stimulation by environmental signals, and that this process requires energy from carbohydrate and fatty acid metabolism. Salinity challenge also induced miRNA expression. These results provide a valuable genomic resource that extends our understanding of the unique biological characteristics of this economically important species under conditions of salinity stress.
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Affiliation(s)
- Yi Tian
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Heishijiao Street, No. 52, Dalian, 116023, China.
| | - Yanpeng Shang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Heishijiao Street, No. 52, Dalian, 116023, China
| | - Ran Guo
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Heishijiao Street, No. 52, Dalian, 116023, China
| | - Yaqing Chang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Heishijiao Street, No. 52, Dalian, 116023, China
| | - Yanan Jiang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Heishijiao Street, No. 52, Dalian, 116023, China
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Gupta AP, Singh P, Garg R, Valicherla GR, Riyazuddin M, Syed AA, Hossain Z, Gayen JR. Pancreastatin inhibitor activates AMPK pathway via GRP78 and ameliorates dexamethasone induced fatty liver disease in C57BL/6 mice. Biomed Pharmacother 2019; 116:108959. [PMID: 31108350 DOI: 10.1016/j.biopha.2019.108959] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/02/2019] [Accepted: 05/03/2019] [Indexed: 12/16/2022] Open
Abstract
AIMS To investigate the role of pancreastatin inhibitor (PSTi8) in lipid homeostasis and insulin sensitivity in dexamethasone induced fatty liver disease associated type 2 diabetes. MAIN METHODS Glucose releases assay, lipid O staining and ATP/AMP ratio were performed in HepG2 cells. Twenty four mice were randomly divided into 4 groups: Control group (saline), DEX (1 mg/kg, im) for 17 days, DEX+PSTi8 (acute 5 mg/kg and chronic 2 mg/kg, ip) for 10 days. The glucose, insulin and pyruvate tolerance tests (GTT, ITT and PTT), biochemical parameters and Oxymax-CLAMS were performed. Further to elucidate the action mechanisms of PSTi8, we performed genes expression and western blotting of biological samples. KEY FINDINGS We found that PSTi8 suppresses hepatic glucose release, lipid deposition, oxidative stress induced by DEX, stimulates the cellular energy level in hepatocytes and enhances GRP78 activity. It reduces lipogensis and enhances fatty acid oxidation to improve insulin sensitivity and glucose tolerance in DEX induced diabetic mice. The above cellular effects are the result of activated AMPK signalling pathway in liver, which increases Srebp1c and ACC phosphorylation. The increased ACC phosphorylation suppresses protein kinase C activity and enhances insulin sensitivity. The increased expression of UCP3 in liver elicits fatty acid oxidation and energy expenditure, which suppress oxidative stress. SIGNIFICANCE Thus the activation of AMPK signalling through GRP78, improves lipid homeostasis, enhances insulin sensitivity via inhibition of PKC activity. PSTi8 suppresses inflammation associated with incomplete fatty acid oxidation. Hence, PSTi8 may be a potential therapeutic agent to treat glucocorticoid-induced fatty liver associated type 2 diabetes.
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Affiliation(s)
- Anand P Gupta
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Pragati Singh
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Richa Garg
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - Guru R Valicherla
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - Mohammed Riyazuddin
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Anees A Syed
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - Zakir Hossain
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Jiaur R Gayen
- Pharmaceutics & Pharmacokinetics Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi, India.
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Tao X, Hu Y, Li L, Xu R, Fu J, Tong Q, Fu Q. Genetic deletion of β 2 adrenergic receptors exacerbates hepatocellular lipid accumulation in high-fat diet mice. Biochem Biophys Res Commun 2019; 511:73-78. [PMID: 30770098 DOI: 10.1016/j.bbrc.2019.02.037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 02/07/2019] [Indexed: 12/12/2022]
Abstract
β2 Adrenergic receptors (β2ARs) are G protein-coupled receptors (GPCRs) that are expressed in major insulin target tissues. β2ARs play an important role in the regulation of lipid metabolism during aging; however, little is known about the significance of β2ARs in the pathogenesis of hepatic fat accumulation in high-fat diet (HFD) mice. This study aims to examine the role of β2AR in the development of nonalcoholic fatty liver disease (NAFLD) induced by HFD and the underlying mechanisms. Surprisingly, we found that genetic deletion of β2AR significantly increased the liver weight of mice fed a HFD for 20 weeks compared to that of wild-type (WT) mice. Moreover, genetic deletion of β2AR could aggravate HFD-induced liver lipid accumulation and liver injury in mice. Mechanistically, we demonstrated that β2AR deletion significantly activated PPARγ/CD36 signaling via inactivation of the cAMP response element-binding (CREB) protein to facilitate hepatocellular lipid deposition in HFD mice. Together, our results identify β2AR as a plausible therapeutic target for preventing or treating NAFLD.
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Affiliation(s)
- Xiang Tao
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Pediatric Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430000, China; Clinical Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430000, China
| | - Yuting Hu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Li
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Rui Xu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Fu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qiangsong Tong
- Department of Pediatric Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430000, China; Clinical Center of Human Gene Research, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430000, China.
| | - Qin Fu
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; The Key Laboratory for Drug Target Research and Pharmacodynamic Evaluation of Hubei Province, Wuhan, 430030, China.
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Chitobiose alleviates oleic acid-induced lipid accumulation by decreasing fatty acid uptake and triglyceride synthesis in HepG2 cells. J Funct Foods 2018. [DOI: 10.1016/j.jff.2018.04.058] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Ansari A, Bose S, Patra JK, Shin NR, Lim DW, Kim KW, Wang JH, Kim YM, Chin YW, Kim H. A Controlled Fermented Samjunghwan Herbal Formula Ameliorates Non-alcoholic Hepatosteatosis in HepG2 Cells and OLETF Rats. Front Pharmacol 2018; 9:596. [PMID: 29971000 PMCID: PMC6018163 DOI: 10.3389/fphar.2018.00596] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/18/2018] [Indexed: 12/19/2022] Open
Abstract
Hepatosteatosis (HS), a clinical feature of fatty liver with the excessive intracellular accumulation of triglyceride in hepatocytes, is manifested by perturbation of the maintenance of liver lipid homeostasis. Samjunghwan (SJH) is an herbal formula used mostly in Korean traditional medicine that is effective against a number of metabolic diseases, including obesity. Herbal drugs, enriched with numerous bioactive substances, possess health-protective benefits. Meanwhile, fermented herbal products enriched with probiotics are known to improve metabolic processes. Additionally, current lines of evidence indicate that probiotics-derived metabolites, termed as postbiotics, produce the same beneficial effects as their precursors. Herein, the anti-HS effects of 5-weeks naturally fermented SJH (FSJH) was investigated with FSJH-mixed chow diet in vivo using Otsuka Long-Evans Tokushima Fatty (OLETF) and Long-Evans Tokushima Otsuka (LETO) rats as animal models of HS and controls, respectively. In parallel, the anti-HS effects of postbiotic-metabolites of three bacterial strains [Lactobacillus brevis (LBB), Lactococcus lactis (LCL) and Lactobacillus plantarum (LBP)] isolated from FSJH were also evaluated in vitro using the FFAs-induced HepG2 cells. Feeding OLETF rats with FSJH-diet effectively reduced body, liver, and visceral adipose tissue (VAT) weights, produced marked hypolipidemic effects on serum and hepatic lipid parameters, decreased serum AST and ALT levels, and upregulated the HMGCOR, SREBP, and ACC, and downregulated the AMPK and LDLR gene expressions levels. Additionally, exposure of FFAs-induced HepG2 cells to postbiotic metabolic media (PMM) of bacterial strains also produced marked hypolipidemic effects on intracellular lipid contents and significantly unregulated the HMGCOR, SREBP, and ACC, and downregulated the AMPK and LDLR genes expressions levels. Overall, our results indicate that FSJH enriched with fermented metabolites could be an effective anti-HS formulation.
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Affiliation(s)
- AbuZar Ansari
- Department of Rehabilitation Medicine of Korean Medicine, Dongguk University, Goyang, South Korea
| | | | - Jayanta Kumar Patra
- Research Institute of Biotechnology and Medical Converged Science, Dongguk University, Goyang, South Korea
| | - Na Rae Shin
- Department of Rehabilitation Medicine of Korean Medicine, Dongguk University, Goyang, South Korea
| | - Dong-Woo Lim
- Department of Pathology, College of Korean Medicine, Dongguk University, Goyang, South Korea
| | - Koh-Woon Kim
- Department of Korean Rehabilitation Medicine, College of Korean Medicine, Kyung Hee University, Seoul, South Korea
| | - Jing-Hua Wang
- Department of Rehabilitation Medicine of Korean Medicine, Dongguk University, Goyang, South Korea
| | - Young-Mi Kim
- College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang, South Korea
| | - Young-Won Chin
- College of Pharmacy and Integrated Research Institute for Drug Development, Dongguk University-Seoul, Goyang, South Korea
| | - Hojun Kim
- Department of Rehabilitation Medicine of Korean Medicine, Dongguk University, Goyang, South Korea
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79
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Berndt N, Bulik S, Wallach I, Wünsch T, König M, Stockmann M, Meierhofer D, Holzhütter HG. HEPATOKIN1 is a biochemistry-based model of liver metabolism for applications in medicine and pharmacology. Nat Commun 2018; 9:2386. [PMID: 29921957 PMCID: PMC6008457 DOI: 10.1038/s41467-018-04720-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 05/14/2018] [Indexed: 12/18/2022] Open
Abstract
The epidemic increase of non-alcoholic fatty liver diseases (NAFLD) requires a deeper understanding of the regulatory circuits controlling the response of liver metabolism to nutritional challenges, medical drugs, and genetic enzyme variants. As in vivo studies of human liver metabolism are encumbered with serious ethical and technical issues, we developed a comprehensive biochemistry-based kinetic model of the central liver metabolism including the regulation of enzyme activities by their reactants, allosteric effectors, and hormone-dependent phosphorylation. The utility of the model for basic research and applications in medicine and pharmacology is illustrated by simulating diurnal variations of the metabolic state of the liver at various perturbations caused by nutritional challenges (alcohol), drugs (valproate), and inherited enzyme disorders (galactosemia). Using proteomics data to scale maximal enzyme activities, the model is used to highlight differences in the metabolic functions of normal hepatocytes and malignant liver cells (adenoma and hepatocellular carcinoma). In silico models of cells can provide insight into the causes and effects of disease states and reduce the need for in vivo studies. Here, the authors present a kinetic model of hepatocyte metabolism including energy, carbohydrate, lipid and nitrogen metabolism and hormonal and allosteric regulation of enzymatic activity.
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Affiliation(s)
- Nikolaus Berndt
- Institute of Biochemistry Computational Systems Biochemistry Group, Charité - Universitätsmedizin Berlin, Charitéplatz, 110117, Berlin, Germany
| | - Sascha Bulik
- Institute of Biochemistry Computational Systems Biochemistry Group, Charité - Universitätsmedizin Berlin, Charitéplatz, 110117, Berlin, Germany.,German Federal Institute for Risk Assessment Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - Iwona Wallach
- Institute of Biochemistry Computational Systems Biochemistry Group, Charité - Universitätsmedizin Berlin, Charitéplatz, 110117, Berlin, Germany
| | - Tilo Wünsch
- Department of General, Visceral and Transplantation Surgery Augustenburger Platz, Charité - Universitätsmedizin Berlin - Campus Virchow-Klinikum, 113353, Berlin, Germany
| | - Matthias König
- Institute for Biology, Institute for Theoretical Biology, Humboldt-University Berlin, Invalidenstraße 43, Haus, 410115, Berlin, Germany
| | - Martin Stockmann
- German Federal Institute for Risk Assessment Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - David Meierhofer
- Max Planck Institute of Molecular Genetics/Mass Spectroscopy, Ihnestraße 63-73, 14195, Berlin, Germany
| | - Hermann-Georg Holzhütter
- Institute of Biochemistry Computational Systems Biochemistry Group, Charité - Universitätsmedizin Berlin, Charitéplatz, 110117, Berlin, Germany.
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80
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Zheng YP, Zhong XY, Huang YS, Zheng CB. HCBP6 Is Involved in the Development of Hepatic Steatosis Induced by High-Fat Diet and CCL4 in Rats. Ann Hepatol 2018; 17:511-518. [PMID: 29735802 DOI: 10.5604/01.3001.0011.7396] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
INTRODUCTION AND AIM Hepatitis C virus core-binding protein 6 (HCBP6) was previously found to be an hepatitis C virus corebinding protein, its biological function remains unclear. Our research aims to investigate the role of HCBP6 in the development of hepatic steatosis induced by high-fat diet and carbon tetrachloride (CCL4) in rats. MATERIAL AND METHODS Eighteen Wistar rats were randomly allocated into 3 groups: control group, model group 1, and model group 2. The control group was treated with a standard diet for 5 weeks. Model groups were treated with high-fat diet and CCL4 injection twice a week for 3 weeks in Group 1 and 5 weeks in Group 2, respectively. After the intervention, hepatic steatosis was observed by histological staining with hematoxylin and eosin (H&E) and Oil Red O staining. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total colesterol (TC), and triglycerides (TGs) were measured. The TG content in liver homogenates was evaluated. Expressions of HCBP6 and SREBP-1c were determined by immunofluorescence, quantitative real-time PCR, and Western blot analysis. RESULTS Hepatic steatosis was successfully induced in model groups. ALT, AST, TC, and TGs elevated in model groups compared with those in control group (P < 0.05). Hepatic steatosis induced by high-fat diet and CCL4 resulted in low expression of HCBP6 and high expression of SREBP-1c in the liver of rats (P < 0.05). CONCLUSION HCBP6 is involved in the development of high-fat diet- and CCL4-induced hepatic steatosis and related negatively with SREBP-1c.
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Affiliation(s)
- Yong-Ping Zheng
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Xian-Yang Zhong
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Yu-Shu Huang
- Department of Gastroenterology, Shantou Central Hospital, Affiliated Hospital of Sun Yat-Sen University, Shantou, Guangdong province, China
| | - Can-Bin Zheng
- Department of Endocrine and Metabolic Diseases, 1st Affiliated Hospital of Shantou University Medical College, Shantou, Guangdong province, China
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81
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Schleicher J, Dahmen U, Guthke R, Schuster S. Zonation of hepatic fat accumulation: insights from mathematical modelling of nutrient gradients and fatty acid uptake. J R Soc Interface 2018; 14:rsif.2017.0443. [PMID: 28835543 DOI: 10.1098/rsif.2017.0443] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 07/28/2017] [Indexed: 02/07/2023] Open
Abstract
Intrinsic of non-alcoholic fatty liver diseases is an aberrant accumulation of triglycerides (steatosis), which occurs inhomogeneously within lobules. To improve our understanding of the mechanisms involved in this zonation patterning, we developed a mathematical multicompartment model of hepatic fatty acid metabolism accompanied by blood flow simulations. A model analysis determines the influence of the uptake process of fatty acids, the porto-central gradient of plasma fatty acid concentration, and the oxygen supply via blood on the zonation of triglyceride accumulation. From this theoretical perspective, the plasma oxygen gradient, but not the fatty acid gradient, leads the way to a zonated triglyceride accumulation by its decisive role in oxidative processes. In addition, the uptake mechanism of fatty acids seems to be fundamental for a pericentral dominance of steatosis. However, the mechanism of cellular fatty acid uptake from the blood is still under debate. Our theoretical approach supports the transporter-mediated uptake mechanism and reveals that the maximal velocity of fatty acid uptake affects the switching between a periportal and a pericentral triglyceride accumulation. Further research on hepatic fatty acid uptake is needed to push forward our understanding of aberrant triglyceride accumulation in diet-induced steatosis.
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Affiliation(s)
- Jana Schleicher
- Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, University Hospital Jena, Jena, Germany .,Department of Bioinformatics, Friedrich-Schiller-University Jena, Jena, Germany
| | - Uta Dahmen
- Experimental Transplantation Surgery, Department of General, Visceral and Vascular Surgery, University Hospital Jena, Jena, Germany
| | - Reinhard Guthke
- Leibniz Institute for Natural Product Research and Infection Biology - Hans Knoell Institute, Jena, Germany
| | - Stefan Schuster
- Department of Bioinformatics, Friedrich-Schiller-University Jena, Jena, Germany
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82
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He D, Zhang P, Sai X, Li X, Wang L, Xu Y. Camellia euphlebia flower extract inhibits oleic acid-induced lipid accumulation via reduction of lipogenesis in HepG2 cells. Eur J Integr Med 2018. [DOI: 10.1016/j.eujim.2017.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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83
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Cedó L, Santos D, Roglans N, Julve J, Pallarès V, Rivas-Urbina A, Llorente-Cortes V, Laguna JC, Blanco-Vaca F, Escolà-Gil JC. Human hepatic lipase overexpression in mice induces hepatic steatosis and obesity through promoting hepatic lipogenesis and white adipose tissue lipolysis and fatty acid uptake. PLoS One 2017; 12:e0189834. [PMID: 29244870 PMCID: PMC5731695 DOI: 10.1371/journal.pone.0189834] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/01/2017] [Indexed: 01/07/2023] Open
Abstract
Human hepatic lipase (hHL) is mainly localized on the hepatocyte cell surface where it hydrolyzes lipids from remnant lipoproteins and high density lipoproteins and promotes their hepatic selective uptake. Furthermore, hepatic lipase (HL) is closely associated with obesity in multiple studies. Therefore, HL may play a key role on lipid homeostasis in liver and white adipose tissue (WAT). In the present study, we aimed to evaluate the effects of hHL expression on hepatic and white adipose triglyceride metabolism in vivo. Experiments were carried out in hHL transgenic and wild-type mice fed a Western-type diet. Triglyceride metabolism studies included β-oxidation and de novo lipogenesis in liver and WAT, hepatic triglyceride secretion, and adipose lipoprotein lipase (LPL)-mediated free fatty acid (FFA) lipolysis and influx. The expression of hHL promoted hepatic triglyceride accumulation and de novo lipogenesis without affecting triglyceride secretion, and this was associated with an upregulation of Srebf1 as well as the main genes controlling the synthesis of fatty acids. Transgenic mice also exhibited more adiposity and an increased LPL-mediated FFA influx into the WAT without affecting glucose tolerance. Our results demonstrate that hHL promoted hepatic steatosis in mice mainly by upregulating de novo lipogenesis. HL also upregulated WAT LPL and promoted triglyceride-rich lipoprotein hydrolysis and adipose FFA uptake. These data support the important role of hHL in regulating hepatic lipid homeostasis and confirm the broad cardiometabolic role of HL.
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Affiliation(s)
- Lídia Cedó
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Hospitalet de Llobregat, Spain
| | - David Santos
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Hospitalet de Llobregat, Spain
| | - Núria Roglans
- Department of Pharmacology and Therapeutic Chemistry, School of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Josep Julve
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Hospitalet de Llobregat, Spain
- Departament de Bioquímica, Biología Molecular i Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Victor Pallarès
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
| | - Andrea Rivas-Urbina
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- Departament de Bioquímica, Biología Molecular i Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Vicenta Llorente-Cortes
- Lipids and Cardiovascular Pathology Group. CSIC-ICCC-IIB-Sant Pau and Instituto de Investigaciones Biomédicas de Barcelona (IibB)-CSIC, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares, CIBERCV, Madrid, Spain
| | - Joan Carles Laguna
- Department of Pharmacology and Therapeutic Chemistry, School of Pharmacy, University of Barcelona, Barcelona, Spain
| | - Francisco Blanco-Vaca
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Hospitalet de Llobregat, Spain
- Departament de Bioquímica, Biología Molecular i Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
- * E-mail: (FBV); (JCE-G)
| | - Joan Carles Escolà-Gil
- Institut d’Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Hospitalet de Llobregat, Spain
- Departament de Bioquímica, Biología Molecular i Biomedicina, Universitat Autònoma de Barcelona, Barcelona, Spain
- * E-mail: (FBV); (JCE-G)
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84
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Abstract
Triglyceride molecules represent the major form of storage and transport of fatty acids within cells and in the plasma. The liver is the central organ for fatty acid metabolism. Fatty acids accrue in liver by hepatocellular uptake from the plasma and by de novo biosynthesis. Fatty acids are eliminated by oxidation within the cell or by secretion into the plasma within triglyceride-rich very low-density lipoproteins. Notwithstanding high fluxes through these pathways, under normal circumstances the liver stores only small amounts of fatty acids as triglycerides. In the setting of overnutrition and obesity, hepatic fatty acid metabolism is altered, commonly leading to the accumulation of triglycerides within hepatocytes, and to a clinical condition known as nonalcoholic fatty liver disease (NAFLD). In this review, we describe the current understanding of fatty acid and triglyceride metabolism in the liver and its regulation in health and disease, identifying potential directions for future research. Advances in understanding the molecular mechanisms underlying the hepatic fat accumulation are critical to the development of targeted therapies for NAFLD. © 2018 American Physiological Society. Compr Physiol 8:1-22, 2018.
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Affiliation(s)
- Michele Alves-Bezerra
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, USA
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85
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Li S, Li J, Zhao Y, Zhang Q, Wang Q. Nutrient sensing signaling integrates nutrient metabolism and intestinal immunity in grass carp, Ctenopharyngodon idellus after prolonged starvation. FISH & SHELLFISH IMMUNOLOGY 2017; 71:50-57. [PMID: 28964867 DOI: 10.1016/j.fsi.2017.09.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/13/2017] [Accepted: 09/17/2017] [Indexed: 06/07/2023]
Abstract
Starvation has been shown to affect growth and nutrient metabolism in fish; however, little information about the nutrient sensing signaling and mucosal adaptive immunity in fish was known. In the present study, grass carp was starved for 8weeks to simulate the natural aquaculture practice in Hubei during winter. The histology of liver was significantly affected with decreased expression of tight junction proteins including claudin-3, claudin-b and ZO-1. Muscle gene expression was also affected, with decreased expression of muscle growth promoting factors such as Myogenin, MyoD, Myf5, and increased expression of muscle degradation factors, such as CathepsinD. In addition, mucosal adaptive immunity was also significantly affected, with decreased expression of antibodies including IgZ and IgM in gut. Along with these changes was the inhibition of several nutrient sensing signaling including MAPK and TOR signaling, which leads to the inhibition of the synthesis of protein including immunoglobulin. The increased phosphorylation of eIF2α not only inhibited the translation, but also resulted in the decreased expression of IkB and increased expression of NF-<kappa>B, with the activation of pro-inflammatory genes including IL8 and TNF<alpha>.
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Affiliation(s)
- Shan Li
- College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Huazhong Agricultural University, No. 1, Shizishan Street, Hongshan District, Wuhan 430070, Hubei Province, China
| | - Jiabo Li
- College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Huazhong Agricultural University, No. 1, Shizishan Street, Hongshan District, Wuhan 430070, Hubei Province, China
| | - Yongliang Zhao
- College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Huazhong Agricultural University, No. 1, Shizishan Street, Hongshan District, Wuhan 430070, Hubei Province, China
| | - Qin Zhang
- Key Laboratory of Marine Biotechnology of Guangxi, Guangxi Institute of Oceanology, Beihai 536000, China
| | - Qingchao Wang
- College of Fisheries, Hubei Provincial Engineering Laboratory for Pond Aquaculture, Huazhong Agricultural University, No. 1, Shizishan Street, Hongshan District, Wuhan 430070, Hubei Province, China.
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86
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Zhang M, Sun W, Zhou M, Tang Y. MicroRNA-27a regulates hepatic lipid metabolism and alleviates NAFLD via repressing FAS and SCD1. Sci Rep 2017; 7:14493. [PMID: 29101357 PMCID: PMC5670231 DOI: 10.1038/s41598-017-15141-x] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 09/22/2017] [Indexed: 02/06/2023] Open
Abstract
MicroRNAs are implicated as crucial mediators in metabolic diseases including obesity, diabetes, and non-alcoholic fatty liver diseases (NAFLD). Here, we show miR-27a attenuated hepatic de novo lipogenesis and alleviated obesity-initiated NAFLD through inhibiting Fasn and Scd1 in liver. Hepatic levels of miR-27a were significantly augmented in HFD-fed and ob/ob mice. Further studies demonstrated that miR-27a directly interacted with 3' untranslated region (3'-UTR) of hepatic Fasn and Scd1 mRNAs and reduced their expression levels in mice. Adenovirus-mediated overexpression of miR-27a robustly blocked sodium oleate-induced triglyceride (TG) accumulation in mouse primary hepatocytes and reduced liver TG contents in mice via repressing hepatic lipogenesis. Furthermore, ectopic expression of hepatic miR-27a impaired lipid contents of livers and attenuated NAFLD development through suppressing lipogenesis in HCD-fed and ob/ob mice. Together, our results reveal a critical role of miR-27a in lipid homeostasis of liver and pathogenesis of NAFLD.
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Affiliation(s)
- Meiyuan Zhang
- Emergency Intensive Care Unit, Qingpu Branch of Zhongshan Hospital, Fudan University, Shanghai, 201700, China
| | - Weilan Sun
- Emergency Intensive Care Unit, Qingpu Branch of Zhongshan Hospital, Fudan University, Shanghai, 201700, China
| | - Minghao Zhou
- Emergency Intensive Care Unit, Qingpu Branch of Zhongshan Hospital, Fudan University, Shanghai, 201700, China
| | - Yan Tang
- Emergency Intensive Care Unit, Qingpu Branch of Zhongshan Hospital, Fudan University, Shanghai, 201700, China.
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87
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Guo Y, Yu J, Wang C, Li K, Liu B, Du Y, Xiao F, Chen S, Guo F. miR-212-5p suppresses lipid accumulation by targeting FAS and SCD1. J Mol Endocrinol 2017; 59:205-217. [PMID: 28667176 DOI: 10.1530/jme-16-0179] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Accepted: 06/29/2017] [Indexed: 12/21/2022]
Abstract
MicroRNAs, a class of small noncoding RNAs, are implicated in controlling a variety of biological processes. We have shown that leucine deprivation suppresses lipogenesis by inhibiting fatty acid synthase (FAS) expression in the liver previously; the aim of our current study is to investigate which kind of microRNA is involved in the regulation of FAS expression in response to leucine deprivation. Here, we indicated that microRNA-212-5p specifically binds to mouse FAS 3'UTR and inhibits its activity. Leucine deficiency significantly increased the mRNA levels of miR-212-5p in the livers of mice. Further studies proved that miR-212-5p also directly binds to the 3'UTR of stearoyl-CoA desaturase-1 (SCD1) to inhibit its activity. Overexpression of miR-212-5p decreases the protein levels of FAS and SCD1 in vitro and in vivo, and silencing of miR-212-5p has the opposite effects in mouse primary hepatocytes. Moreover, overexpression of miR-212-5p significantly decreases triglyceride (TG) accumulation in primary hepatocytes and in the livers of mice injected with adenovirus-mediated overexpressing of miR-212-5p (Ad-miR-212). Interestingly, inhibition of miR-212-5p reverses the suppressive effects of leucine deficiency on FAS and SCD1 expression, as well as TG accumulation in mouse primary hepatocytes. Finally, we demonstrate that leucine deficiency induces the expression of miR-212-5p in a GCN2/ATF4-dependent manner. Taken together, our results demonstrate a novel function of hepatic miR-212-5p in the regulation of lipid metabolism which represents a potential therapeutic target for the treatment of non-alcohol fatty liver diseases (NAFLD).
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Affiliation(s)
- Yajie Guo
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Junjie Yu
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Chunxia Wang
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Kai Li
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Bin Liu
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Ying Du
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Fei Xiao
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Shanghai Chen
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Feifan Guo
- Key Laboratory of Nutrition and MetabolismInstitute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
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88
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Liu Y, Ma T, Huang C, Li J. Signal transducer and activator of transcription 5 negatively regulates CD36, a potential diagnostic and therapeutic target for hepatic lipid metabolism. Hepatol Res 2017; 47:1219-1220. [PMID: 27922738 DOI: 10.1111/hepr.12849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 11/28/2016] [Accepted: 11/28/2016] [Indexed: 02/08/2023]
Affiliation(s)
- Yaru Liu
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases, Anhui Medical University, Hefei, China
| | - Taotao Ma
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases, Anhui Medical University, Hefei, China
| | - Cheng Huang
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases, Anhui Medical University, Hefei, China
| | - Jun Li
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases, Anhui Medical University, Hefei, China
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89
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The Clinical Implications of Fatty Pancreas: A Concise Review. Dig Dis Sci 2017; 62:2658-2667. [PMID: 28791556 DOI: 10.1007/s10620-017-4700-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 07/27/2017] [Indexed: 12/19/2022]
Abstract
Fatty pancreas is a newly recognized condition which is poorly investigated until today as compared to nonalcoholic fatty liver disease. It is characterized by pancreatic fat accumulation and subsequent development of pancreatic and metabolic complications. Association of fatty pancreas have been described with type 2 diabetes mellitus, acute and chronic pancreatitis and even pancreatic carcinoma. In this review article, we provide an update on clinical implications, pathogenesis, diagnosis, treatment and outcomes.
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90
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Bellanti F, Villani R, Facciorusso A, Vendemiale G, Serviddio G. Lipid oxidation products in the pathogenesis of non-alcoholic steatohepatitis. Free Radic Biol Med 2017; 111:173-185. [PMID: 28109892 DOI: 10.1016/j.freeradbiomed.2017.01.023] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Revised: 01/11/2017] [Accepted: 01/15/2017] [Indexed: 02/08/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the major public health challenge for hepatologists in the twenty-first century. NAFLD comprises a histological spectrum ranging from simple steatosis or fatty liver, to steatohepatitis, fibrosis, and cirrhosis. It can be categorized into two principal phenotypes: (1) non-alcoholic fatty liver (NAFL), and (2) non-alcoholic steatohepatitis (NASH). The mechanisms of NAFLD progression consist of lipid homeostasis alterations, redox unbalance, insulin resistance, and inflammation in the liver. Even though several studies show an association between the levels of lipid oxidation products and disease state, experimental evidence suggests that compounds such as reactive aldehydes and cholesterol oxidation products, in addition to representing hallmarks of hepatic oxidative damage, may behave as active players in liver dysfunction and the development of NAFLD. This review summarizes the processes that contribute to the metabolic alterations occurring in fatty liver that produce fatty acid and cholesterol oxidation products in NAFLD, with a focus on inflammation, the control of insulin signalling, and the transcription factors involved in lipid metabolism.
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Affiliation(s)
- Francesco Bellanti
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia, Foggia 71122, Italy
| | - Rosanna Villani
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia, Foggia 71122, Italy
| | - Antonio Facciorusso
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia, Foggia 71122, Italy
| | - Gianluigi Vendemiale
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia, Foggia 71122, Italy
| | - Gaetano Serviddio
- C.U.R.E. Centre for Liver Diseases Research and Treatment, Institute of Internal Medicine, Department of Medical and Surgical Sciences, University of Foggia, Foggia 71122, Italy.
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91
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Geidl-Flueck B, Gerber PA. Insights into the Hexose Liver Metabolism-Glucose versus Fructose. Nutrients 2017; 9:E1026. [PMID: 28926951 PMCID: PMC5622786 DOI: 10.3390/nu9091026] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/09/2017] [Accepted: 09/11/2017] [Indexed: 12/15/2022] Open
Abstract
High-fructose intake in healthy men is associated with characteristics of metabolic syndrome. Extensive knowledge exists about the differences between hepatic fructose and glucose metabolism and fructose-specific mechanisms favoring the development of metabolic disturbances. Nevertheless, the causal relationship between fructose consumption and metabolic alterations is still debated. Multiple effects of fructose on hepatic metabolism are attributed to the fact that the liver represents the major sink of fructose. Fructose, as a lipogenic substrate and potent inducer of lipogenic enzyme expression, enhances fatty acid synthesis. Consequently, increased hepatic diacylglycerols (DAG) are thought to directly interfere with insulin signaling. However, independently of this effect, fructose may also counteract insulin-mediated effects on liver metabolism by a range of mechanisms. It may drive gluconeogenesis not only as a gluconeogenic substrate, but also as a potent inducer of carbohydrate responsive element binding protein (ChREBP), which induces the expression of lipogenic enzymes as well as gluconeogenic enzymes. It remains a challenge to determine the relative contributions of the impact of fructose on hepatic transcriptome, proteome and allosterome changes and consequently on the regulation of plasma glucose metabolism/homeostasis. Mathematical models exist modeling hepatic glucose metabolism. Future models should not only consider the hepatic adjustments of enzyme abundances and activities in response to changing plasma glucose and insulin/glucagon concentrations, but also to varying fructose concentrations for defining the role of fructose in the hepatic control of plasma glucose homeostasis.
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Affiliation(s)
- Bettina Geidl-Flueck
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091 Zurich, Switzerland.
| | - Philipp A Gerber
- Division of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital Zurich, 8091 Zurich, Switzerland.
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92
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Feeding-fasting dependent recruitment of membrane microdomain proteins to lipid droplets purified from the liver. PLoS One 2017; 12:e0183022. [PMID: 28800633 PMCID: PMC5553754 DOI: 10.1371/journal.pone.0183022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 07/30/2017] [Indexed: 01/23/2023] Open
Abstract
Lipid droplets (LDs) are cellular stores of neutral fat that facilitate lipid and protein trafficking in response to metabolic cues. Unlike other vesicles, the phospholipid membrane on the LD is a monolayer. Interestingly, this monolayer membrane has free cholesterol, and may therefore contain lipid microdomains that serve as a platform for assembling proteins involved in signal transduction, cell polarity, pathogen entry etc. In support of this, cell culture studies have detected microdomain-associated "raftophilic" proteins on LDs. However, the physiological significance of this observation has been unclear. Here we show that two proteins (Flotillin-1 and SNAP23) that bind to membrane microdomains associate differently with LDs purified from rat liver depending on the feeding/fasting state of the animal. Flotillin-1 increases on LDs in the fed state, possibly because LDs interact with the endoplasmic reticulum (ER), facilitating supply of flotillin-1 from ER to LDs. Interestingly, this increase in flotillin-1 is correlated with an increase in free cholesterol on the LDs in fed state. In opposite behaviour to flotillin-1, SNAP23 increases on LDs in the fasted state and this appears to mediate LD-mitochondria interactions. Such LD-mitochondria interactions may provide fatty acids to mitochondria for promoting beta-oxidation in hepatocytes in response to fasting. Our work brings out physiologically relevant aspects of lipid droplet biology that are different from, and may not be entirely possible to replicate and study in cell culture.
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93
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Cheng J, Liu C, Hu K, Greenberg A, Wu D, Ausman LM, McBurney MW, Wang XD. Ablation of systemic SIRT1 activity promotes nonalcoholic fatty liver disease by affecting liver-mesenteric adipose tissue fatty acid mobilization. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2783-2790. [PMID: 28789977 DOI: 10.1016/j.bbadis.2017.08.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/14/2017] [Accepted: 08/04/2017] [Indexed: 12/12/2022]
Abstract
Sirtuin 1 (SIRT1) has been reported to protect against nonalcoholic fatty liver disease (NAFLD) development. The mechanism of how SIRT1 deacetylase activity affects NAFLD has not been well investigated. The current investigation addressed the causal effect of systemic SIRT1 activity on NAFLD development and the underlying mechanism involved in both liver and mesenteric adipose tissue (MAT). Both SIRT1 homozygous mice ablated the catalytic activity (sirt1Y/Y) and their corresponding wild type littermates (WT) were fed a high fat diet (HFD, 60% calories from fat) for 34weeks. Sirt1Y/Y mice showed significantly higher level of hepatic triglyceride which was accompanied with higher levels of SREBP-1 and SCD1and decreased phosphorylation of LKB1 and AMPK in the liver. Compared with WT mice, mRNA expression of lipogenic genes (lxrα, srebp-1c, scd1 and fas) in the MAT increased significantly in sirt1Y/Y mice. Fatty acid oxidation biomarkers (acox1, acox3, cpt, ucp1, sirt3) in both liver and MAT were comparable between groups. Interestingly, we observed that in sirt1Y/Y mice, the mRNA level of hormone sensitive lipase (hsl), adipose triglyceride lipase (atgl) and perilipin-2 (plin-2), all involved in lipolysis, significantly increased in MAT, but not in epididymal adipose tissue. These changes positively correlated with circulating free fatty acid (FFA) concentrations and higher hepatic mRNA expression of cd36 for FFA uptake. The present study has provided novel evidence to suggest that under HFD-induced metabolic surplus, the lack of SIRT1 catalytic activity promotes release of FFA from MAT and escalate NAFLD by interfering with lipid homeostasis in both liver and MAT.
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Affiliation(s)
- Junrui Cheng
- Nutrition and Cancer Biology Lab, JM USDA-HNRCA at Tufts University, USA; Friedman School of Nutrition and Policy, Tufts University, Boston, MA, USA
| | - Chun Liu
- Nutrition and Cancer Biology Lab, JM USDA-HNRCA at Tufts University, USA
| | - Kangquan Hu
- Nutrition and Cancer Biology Lab, JM USDA-HNRCA at Tufts University, USA
| | - Andrew Greenberg
- Obesity and Metabolism Lab, JM USDA-HNRCA at Tufts University, USA; Friedman School of Nutrition and Policy, Tufts University, Boston, MA, USA
| | - Dayong Wu
- Nutritional Immunology Lab, JM USDA-HNRCA at Tufts University, USA; Friedman School of Nutrition and Policy, Tufts University, Boston, MA, USA
| | - Lynne M Ausman
- Nutrition and Cancer Biology Lab, JM USDA-HNRCA at Tufts University, USA; Friedman School of Nutrition and Policy, Tufts University, Boston, MA, USA
| | - Michael W McBurney
- Department of Medicine, Microbiology and Immunology Lab, University of Ottawa, Ontario, Canada
| | - Xiang-Dong Wang
- Nutrition and Cancer Biology Lab, JM USDA-HNRCA at Tufts University, USA; Friedman School of Nutrition and Policy, Tufts University, Boston, MA, USA.
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94
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PEGylated Curcumin Derivative Attenuates Hepatic Steatosis via CREB/PPAR- γ/CD36 Pathway. BIOMED RESEARCH INTERNATIONAL 2017; 2017:8234507. [PMID: 28770225 PMCID: PMC5523402 DOI: 10.1155/2017/8234507] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 05/29/2017] [Accepted: 05/31/2017] [Indexed: 01/01/2023]
Abstract
Curcumin has the potential to cure dyslipidemia and nonalcoholic fatty liver disease (NAFLD). However, its therapeutic effects are curbed by poor bioavailability. Our previous work has shown that modification of curcumin with polyethylene glycol (PEG) improves blood concentration and tissue distribution. This study sought to investigate the role of a novel PEGylated curcumin derivative (Curc-mPEG454) in regulating hepatic lipid metabolism and to elucidate the underlying molecular mechanism in a high-fat-diet- (HFD-) fed C57BL/6J mouse model. Mice were fed either a control chow diet (D12450B), an HFD (D12492) as the NAFLD model, or an HFD with Curc-mPEG454 administered by intraperitoneal injection at 50 mg/kg or 100 mg/kg for 16 weeks. We found that Curc-mPEG454 significantly lowered the body weight and serum triglyceride (TG) levels and reduced liver lipid accumulation in HFD-induced NAFLD mice. It was also shown that Curc-mPEG454 suppressed the HFD-induced upregulated expression of CD36 and hepatic peroxisome proliferator activated receptor-γ (PPAR-γ), a positive regulator of CD36. Moreover, Curc-mPEG454 dramatically activated cAMP response element-binding (CREB) protein, which negatively controls hepatic PPAR-γ expression. These findings suggest that Curc-mPEG454 reverses HFD-induced hepatic steatosis via the activation of CREB inhibition of the hepatic PPAR-γ/CD36 pathway, which may be an effective therapeutic for high-fat-diet-induced NAFLD.
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95
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Geng C, Xu H, Zhang Y, Gao Y, Li M, Liu X, Gao M, Wang X, Liu X, Fang F, Chang Y. Retinoic acid ameliorates high-fat diet-induced liver steatosis through sirt1. SCIENCE CHINA-LIFE SCIENCES 2017; 60:1234-1241. [PMID: 28667519 DOI: 10.1007/s11427-016-9027-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 03/17/2017] [Indexed: 12/17/2022]
Abstract
In this study, treatment of C57BL/6J (wild type, WT) mice fed a high-fat diet (HFD) with retinoic acid (RA) decreased body weight and subcutaneous and visceral fat content, reversed the apparent hepatosteatosis, and reduced hepatic intracellular triglyceride and serum alanine transaminase (ALT) and aspartate aminotransferase (AST) concentrations. Moreover, RA treatment improved glucose tolerance and insulin sensitivity in WT mice fed a HFD. However, these RA-induced effects in WT mice fed a HFD were alleviated in liver specific Sirtuin 1 (Sirt1) deficient (LKO) mice fed a HFD. Furthermore, RA also could not improve glucose tolerance and insulin sensitivity in LKO mice fed a HFD. The mechanism studies indicated that RA indeed increased the expression of hepatic Sirt1 and superoxide dismutase 2 (Sod2), and inhibited the expression of sterol regulatory element binding protein 1c (Srebp-1c) in WT mice in vivo and in vitro. RA decreased mitochondrial reactive oxygen species (ROS) production in WT primary hepatocytes and increased mitochondrial DNA (mtDNA) copy number in WT mice liver. However, these RA-mediated molecular effects were also abolished in the liver and primary hepatocytes from LKO mice. In summary, RA protected against HFD-induced hepatosteatosis by decreasing Srebp-1c expression and improving antioxidant capacity through a Sirt1-mediated mechanism.
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Affiliation(s)
- Chao Geng
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Haifeng Xu
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Interventional Therapy, Peking University Cancer Hospital & Institute, Beijing, 100142, China
| | - Yinliang Zhang
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Yong Gao
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Meixia Li
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaoyan Liu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Mingyue Gao
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Xiaojuan Wang
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China
| | - Xiaojun Liu
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China.
| | - Fude Fang
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China.
| | - Yongsheng Chang
- State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & School of Basic Medicine Peking Union Medical College, Beijing, 100005, China.
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96
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Schulze RJ, Drižytė K, Casey CA, McNiven MA. Hepatic Lipophagy: New Insights into Autophagic Catabolism of Lipid Droplets in the Liver. Hepatol Commun 2017; 1:359-369. [PMID: 29109982 PMCID: PMC5669271 DOI: 10.1002/hep4.1056] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The liver is a central fat‐storage organ, making it especially susceptible to steatosis as well as subsequent inflammation and cirrhosis. The mechanisms by which the liver mobilizes stored lipid for energy production, however, remain incompletely defined. The catabolic process of autophagy, a well‐known process of bulk cytoplasmic recycling and cellular self‐regeneration, is a central regulator of lipid metabolism in the liver. In the past decade, numerous studies have examined a selective form of autophagy that specifically targets a unique neutral lipid storage organelle, the lipid droplet, to better understand the function for this process in hepatocellular fatty acid metabolism. In the liver (and other oxidative tissues), this specialized pathway, lipophagy, likely plays as important a role in lipid turnover as conventional lipase‐driven lipolysis. In this review, we highlight several recent studies that have contributed to our understanding about the regulation and effects of hepatic lipophagy. (Hepatology Communications 2017;1:359–369)
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Affiliation(s)
- Ryan J Schulze
- Department of Biochemistry and Molecular Biology and the Center for Digestive Diseases, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905, USA
| | - Kristina Drižytė
- Department of Biochemistry and Molecular Biology and the Center for Digestive Diseases, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905, USA.,Biochemistry and Molecular Biology Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, 200 1st St SW, Rochester, MN 55905, USA
| | - Carol A Casey
- Department of Internal Medicine, University of Nebraska Medical Center, 988090 Nebraska Medical Center, Omaha, NE, 68198, USA.,Research Service, VA Nebraska-Western Iowa Health Care System (VA NWIHCS), Omaha, NE, 68198, USA
| | - Mark A McNiven
- Department of Biochemistry and Molecular Biology and the Center for Digestive Diseases, Mayo Clinic, 200 1st St SW, Rochester, MN, 55905, USA
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97
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Wang C, Liu W, Yao L, Zhang X, Zhang X, Ye C, Jiang H, He J, Zhu Y, Ai D. Hydroxyeicosapentaenoic acids and epoxyeicosatetraenoic acids attenuate early occurrence of nonalcoholic fatty liver disease. Br J Pharmacol 2017; 174:2358-2372. [PMID: 28471490 DOI: 10.1111/bph.13844] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 04/20/2017] [Accepted: 04/22/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE The ω-3 polyunsaturated fatty acids (PUFAs) mediate protective effects on several metabolic disorders. However, the functions of their metabolites in the early stage of nonalcoholic fatty liver disease (NAFLD) are largely unknown. EXPERIMENTAL APPROACH Mice were fed a control diet, high-fat diet (HFD) or ω-3 PUFA-enriched HFD (ω3HFD) for 4 days and phenotypes were analysed. LC-MS/MS was used to determine the eicosanoid profiles. Primary hepatocytes and peritoneal macrophages were used for the mechanism study. KEY RESULTS In short-term HFD-fed mice, the significantly increased lipid accumulation in the liver was reversed by ω-3 PUFA supplementation. Metabolomics showed that the plasma concentrations of hydroxyeicosapentaenoic acids (HEPEs) and epoxyeicosatetraenoic acids (EEQs) were reduced by a short-term HFD and markedly increased by the ω3HFD. However, HEPE/EEQ treatment had no direct protective effect on hepatocytes. ω3HFD also significantly attenuated HFD-induced adipose tissue inflammation. Furthermore, the expression of pro-inflammatory cytokines and activation of the JNK pathway induced by palmitate were suppressed by HEPEs and EEQs in macrophages. 17,18-EEQ, 5-HEPE and 9-HEPE were identified as the effective components among these metabolites, as indicated by their greater suppression of the palmitate-induced expression of inflammatory factors, chemotaxis and JNK activation compared to other metabolites in macrophages. A mixture of 17,18-EEQ, 5-HEPE and 9-HEPE significantly ameliorated the short-term HFD-induced accumulation of macrophages in adipose tissue and hepatic steatosis. CONCLUSION AND IMPLICATIONS 17,18-EEQ, 5-HEPE and 9-HEPE may be potential approaches to prevent NAFLD in the early stage by inhibiting the inflammatory response in adipose tissue macrophages via JNK signalling.
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Affiliation(s)
- Chunjiong Wang
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Wenli Liu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Liu Yao
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Xuejiao Zhang
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Xu Zhang
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Chenji Ye
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Hongfeng Jiang
- Division of Molecular Medicine, Department of Medicine, Columbia University, New York, NY, USA
| | - Jinlong He
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Yi Zhu
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Ding Ai
- Tianjin Key Laboratory of Metabolic Diseases, Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
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98
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Chen G, Li H, Zhao Y, Zhu H, Cai E, Gao Y, Liu S, Yang H, Zhang L. Saponins from stems and leaves of Panax ginseng prevent obesity via regulating thermogenesis, lipogenesis and lipolysis in high-fat diet-induced obese C57BL/6 mice. Food Chem Toxicol 2017; 106:393-403. [PMID: 28599882 DOI: 10.1016/j.fct.2017.06.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 06/02/2017] [Accepted: 06/05/2017] [Indexed: 02/06/2023]
Abstract
In this study, high-fat diet (HFD)-induced obesity in mouse model was used to evaluate the dietary effect of saponins from stems and leaves of Panax ginseng (SLG), and to explore its mechanism of action in producing anti-obesity effects. The results indicate that SLG showed significant anti-obesity effects in diet-induced obese mice, represented by decreased serum levels of free fatty acids (FFA), total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL)-cholesterol, glucose, leptin and insulin, as well as a reduction in overall body and liver weight, epididymal adipose tissue weight, and food efficiency, and inhibition of abnormal increases in acyl carnitine levels normally caused by an HFD. Additionally, the down-regulated expression of PPARγ, FAS, CD36, FATP2 and up-regulated expression of CPT-1, UCP-2, PPARα, HSL, and ATGL in liver tissue was induced by SLG. In addition, the SLG groups showed decreased PPARγ, aP2 and leptin mRNA levels and increased expression of PPARα, PGC-1α, UCP-1 and UCP-3 genes in adipose tissues, compared with the HFD group. In short, SLG may play a key role in producing anti-obesity effects in mice fed an HFD, and its mechanism may be related to regulation of thermogenesis, lipogenesis and lipolysis.
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Affiliation(s)
- Guilin Chen
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
| | - Haijun Li
- Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, China
| | - Yan Zhao
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China.
| | - Hongyan Zhu
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
| | - Enbo Cai
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
| | - Yugang Gao
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China.
| | - Shuangli Liu
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
| | - He Yang
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
| | - Lianxue Zhang
- College of Chinese Medicinal Materials, Jilin Agriculture University, Changchun, China
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99
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Bai X, Hong W, Cai P, Chen Y, Xu C, Cao D, Yu W, Zhao Z, Huang M, Jin J. Valproate induced hepatic steatosis by enhanced fatty acid uptake and triglyceride synthesis. Toxicol Appl Pharmacol 2017; 324:12-25. [PMID: 28366540 DOI: 10.1016/j.taap.2017.03.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 03/06/2017] [Accepted: 03/28/2017] [Indexed: 02/07/2023]
Abstract
Steatosis is the characteristic type of VPA-induced hepatotoxicity and may result in life-threatening hepatic lesion. Approximately 61% of patients treated with VPA have been diagnosed with hepatic steatosis through ultrasound examination. However, the mechanisms underlying VPA-induced intracellular fat accumulation are not yet fully understood. Here we demonstrated the involvement of fatty acid uptake and lipogenesis in VPA-induced hepatic steatosis in vitro and in vivo by using quantitative real-time PCR (qRT-PCR) analysis, western blotting analysis, fatty acid uptake assays, Nile Red staining assays, and Oil Red O staining assays. Specifically, we found that the expression of cluster of differentiation 36 (CD36), an important fatty acid transport, and diacylglycerol acyltransferase 2 (DGAT2) were significantly up-regulated in HepG2 cells and livers of C57B/6J mice after treatment with VPA. Furthermore, VPA treatment remarkably enhanced the efficiency of fatty acid uptake mediated by CD36, while this effect was abolished by the interference with CD36-specific siRNA. Also, VPA treatment significantly increased DGAT2 expression as a result of the inhibition of mitogen-activated protein kinase kinase (MEK) - extracellular regulated kinase (ERK) pathway; however, DGAT2 knockdown significantly alleviated VPA-induced intracellular lipid accumulation. Additionally, we also found that sterol regulatory element binding protein-1c (SREBP-1c)-mediated fatty acid synthesis may be not involved in VPA-induced hepatic steatosis. Overall, VPA-triggered over-regulation of CD36 and DGAT2 could be helpful for a better understanding of the mechanisms underlying VPA-induced hepatic steatosis and may offer novel therapeutic strategies to combat VPA-induced hepatotoxicity.
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Affiliation(s)
- Xupeng Bai
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Weipeng Hong
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Peiheng Cai
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yibei Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Chuncao Xu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Di Cao
- School of Chinese Materia Medica, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Weibang Yu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zhongxiang Zhao
- School of Chinese Materia Medica, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Min Huang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jing Jin
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China.
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100
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Lee JW, Mok HJ, Lee DY, Park SC, Kim GS, Lee SE, Lee YS, Kim KP, Kim HD. UPLC-QqQ/MS-Based Lipidomics Approach To Characterize Lipid Alterations in Inflammatory Macrophages. J Proteome Res 2017; 16:1460-1469. [DOI: 10.1021/acs.jproteome.6b00848] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jae Won Lee
- Department
of Applied Chemistry, The Institute of Natural Science, College of
Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
| | - Hyuck Jun Mok
- Department
of Applied Chemistry, The Institute of Natural Science, College of
Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Dae Young Lee
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
| | - Seung Cheol Park
- Department
of Applied Chemistry, The Institute of Natural Science, College of
Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Geum-Soog Kim
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
| | - Seung-Eun Lee
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
| | - Young-Seob Lee
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
| | - Kwang Pyo Kim
- Department
of Applied Chemistry, The Institute of Natural Science, College of
Applied Science, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Hyung Don Kim
- Department
of Herbal Crop Research, National Institute of Horticultural and Herbal Science, RDA, Eumseong 27709, Republic of Korea
- Department
of Biochemistry, School of Life Sciences, Chungbuk National University, Cheongju 28644, Republic of Korea
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