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Harada N, Yoshikatsu A, Yamamoto H, Nakaya Y. 2-Deoxy-D-Glucose Downregulates Fatty Acid Synthase Gene Expression Via an Endoplasmic Reticulum Stress-Dependent Pathway in HeLa Cells. Cell Biochem Biophys 2024:10.1007/s12013-024-01339-0. [PMID: 38824236 DOI: 10.1007/s12013-024-01339-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2024] [Indexed: 06/03/2024]
Abstract
Fatty acid synthase (FASN) catalyzes the rate-limiting step of cellular lipogenesis. FASN expression is upregulated in various types of cancer cells, implying that FASN is a potential target for cancer therapy. 2-Deoxy-D-glucose (2-DG) specifically targets cancer cells by inhibiting glycolysis and glucose metabolism, resulting in multiple anticancer effects. However, whether the effects of 2-DG involve lipogenic metabolism remains to be elucidated. We investigated the effect of 2-DG administration on FASN expression in HeLa human cervical cancer cells. 2-DG treatment for 24 h decreased FASN mRNA and protein levels and suppressed the activity of an exogenous rat Fasn promoter. The use of a chemical activator or inhibitors or of a mammalian expression plasmid showed that neither AMPK nor the Sp1 transcription factor is responsible for the inhibitory effect of 2-DG on FASN expression. Administration of thapsigargin, an endoplasmic reticulum (ER) stress inducer, or 4-(2-aminoethyl) benzenesulfonyl fluoride (AEBSF), a site 1 protease inhibitor, mimicked the inhibitory effect of 2-DG on FASN expression. 2-DG did not further decrease FASN expression in the presence of thapsigargin or AEBSF. Site 1 protease mediates activation of ATF6, an ER stress mediator, as well as sterol regulatory element-binding protein 1 (SREBP1), a robust transcription factor for FASN. Administration of 2-DG or thapsigargin for 24 h suppressed activation of ATF6 and SREBP1, as did AEBSF. We speculated that these effects of 2-DG or thapsigargin are due to feedback inhibition via increased GRP78 expression following ER stress. Supporting this, exogenous overexpression of GRP78 in HeLa cells suppressed SREBP1 activation and Fasn promoter activity. These results suggest that 2-DG suppresses FASN expression via an ER stress-dependent pathway, providing new insight into the molecular basis of FASN regulation in cancer.
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Affiliation(s)
- Nagakatsu Harada
- Department of Health and Nutrition, Faculty of Nursing and Nutrition, The University of Shimane, 151 Nishihayashigi, Izumo city, 693-8550, Shimane, Japan.
| | - Aya Yoshikatsu
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima city, 770-8503, Tokushima, Japan
| | - Hironori Yamamoto
- Department of Health and Nutrition, Faculty of Human Life, Jin-ai University, 3-1-1 Ohde-cho, Echizen city, 915-8568, Fukui, Japan
| | - Yutaka Nakaya
- Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima city, 770-8503, Tokushima, Japan
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Danielewski M, Rapak A, Kruszyńska A, Małodobra-Mazur M, Oleszkiewicz P, Dzimira S, Kucharska AZ, Słupski W, Matuszewska A, Nowak B, Szeląg A, Piórecki N, Zaleska-Dorobisz U, Sozański T. Cornelian Cherry ( Cornus mas L.) Fruit Extract Lowers SREBP-1c and C/EBPα in Liver and Alters Various PPAR-α, PPAR-γ, LXR-α Target Genes in Cholesterol-Rich Diet Rabbit Model. Int J Mol Sci 2024; 25:1199. [PMID: 38256272 PMCID: PMC10816641 DOI: 10.3390/ijms25021199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 01/13/2024] [Accepted: 01/16/2024] [Indexed: 01/24/2024] Open
Abstract
Cornelian cherry (Cornus mas L.) fruits, abundant in iridoids and anthocyanins, are natural products with proven beneficial impacts on the functions of the cardiovascular system and the liver. This study aims to assess and compare whether and to what extent two different doses of resin-purified cornelian cherry extract (10 mg/kg b.w. or 50 mg/kg b.w.) applied in a cholesterol-rich diet rabbit model affect the levels of sterol regulatory element-binding protein 1c (SREBP-1c) and CCAAT/enhancer binding protein α (C/EBPα), and various liver X receptor-α (LXR-α), peroxisome proliferator-activated receptor-α (PPAR-α), and peroxisome proliferator-activated receptor-γ (PPAR-γ) target genes. Moreover, the aim is to evaluate the resistive index (RI) of common carotid arteries (CCAs) and aortas, and histopathological changes in CCAs. For this purpose, the levels of SREBP-1c, C/EBPα, ATP-binding cassette transporter A1 (ABCA1), ATP-binding cassette transporter G1 (ABCG1), fatty acid synthase (FAS), endothelial lipase (LIPG), carnitine palmitoyltransferase 1A (CPT1A), and adiponectin receptor 2 (AdipoR2) in liver tissue were measured. Also, the levels of lipoprotein lipase (LPL), visceral adipose tissue-derived serine protease inhibitor (Vaspin), and retinol-binding protein 4 (RBP4) in visceral adipose tissue were measured. The RI of CCAs and aortas, and histopathological changes in CCAs, were indicated. The oral administration of the cornelian cherry extract decreased the SREBP-1c and C/EBPα in both doses. The dose of 10 mg/kg b.w. increased ABCA1 and decreased FAS, CPT1A, and RBP4, and the dose of 50 mg/kg b.w. enhanced ABCG1 and AdipoR2. Mitigations in atheromatous changes in rabbits' CCAs were also observed. The obtained outcomes were compared to the results of our previous works. The beneficial results confirm that cornelian cherry fruit extract may constitute a potentially effective product in the prevention and treatment of obesity-related disorders.
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Affiliation(s)
- Maciej Danielewski
- Department of Pharmacology, Wroclaw Medical University, J. Mikulicza-Radeckiego 2, 50-345 Wroclaw, Poland; (W.S.); (A.M.); (B.N.); (A.S.)
| | - Andrzej Rapak
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla 12, 53-114 Wroclaw, Poland; (A.R.); (A.K.)
| | - Angelika Kruszyńska
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla 12, 53-114 Wroclaw, Poland; (A.R.); (A.K.)
| | - Małgorzata Małodobra-Mazur
- Department of Forensic Medicine, Division of Molecular Techniques, Wroclaw Medical University, M. Sklodowskiej-Curie 52, 50-369 Wroclaw, Poland;
| | - Paweł Oleszkiewicz
- Department of Radiology and Imaging Diagnostics II, Lower Silesian Center of Oncology, Pulmonology and Hematology, Grabiszynska 105, 53-439 Wroclaw, Poland;
| | - Stanisław Dzimira
- Department of Pathology, Wroclaw University of Environmental and Life Sciences, C. K. Norwida 31, 50-375 Wroclaw, Poland;
| | - Alicja Z. Kucharska
- Department of Fruit, Vegetable, and Plant Nutraceutical Technology, Wroclaw University of Environmental and Life Sciences, J. Chelmonskiego 37, 51-630 Wroclaw, Poland;
| | - Wojciech Słupski
- Department of Pharmacology, Wroclaw Medical University, J. Mikulicza-Radeckiego 2, 50-345 Wroclaw, Poland; (W.S.); (A.M.); (B.N.); (A.S.)
| | - Agnieszka Matuszewska
- Department of Pharmacology, Wroclaw Medical University, J. Mikulicza-Radeckiego 2, 50-345 Wroclaw, Poland; (W.S.); (A.M.); (B.N.); (A.S.)
| | - Beata Nowak
- Department of Pharmacology, Wroclaw Medical University, J. Mikulicza-Radeckiego 2, 50-345 Wroclaw, Poland; (W.S.); (A.M.); (B.N.); (A.S.)
| | - Adam Szeląg
- Department of Pharmacology, Wroclaw Medical University, J. Mikulicza-Radeckiego 2, 50-345 Wroclaw, Poland; (W.S.); (A.M.); (B.N.); (A.S.)
| | - Narcyz Piórecki
- Bolestraszyce Arboretum and Institute of Physiography, Bolestraszyce 130, 37-722 Wyszatyce, Poland;
- Institute of Physical Culture Sciences, Medical College, University of Rzeszow, Cicha 2A, 35-326 Rzeszow, Poland
| | - Urszula Zaleska-Dorobisz
- Department of General and Pediatric Radiology, Wroclaw Medical University, M. Sklodowskiej-Curie 50/52, 50-369 Wroclaw, Poland;
| | - Tomasz Sozański
- Department of Preclinical Sciences, Pharmacology and Medical Diagnostics, Faculty of Medicine, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland;
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Gozdzik P, Czumaj A, Sledzinski T, Mika A. Branched-chain fatty acids affect the expression of fatty acid synthase and C-reactive protein genes in the hepatocyte cell line. Biosci Rep 2023; 43:BSR20230114. [PMID: 37850622 PMCID: PMC10619197 DOI: 10.1042/bsr20230114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 10/03/2023] [Accepted: 10/17/2023] [Indexed: 10/19/2023] Open
Abstract
Fatty acids (FAs) are known to play an important role in human metabolism; however, still little is known about the functions of certain FA classes present in blood at relatively low concentrations. Examples of such compounds include branched-chain fatty acids (BCFAs). Recently, lowered BCFAs blood concentration was noticed in obese patients. An inverse correlation was found between serum concentrations of BCFAs and triglyceride levels, as well as C-reactive protein (CRP) concentration. Obesity is the most frequently observed component of metabolic syndrome and both disorders are accompanied by the dysregulation of FAs metabolism. However, not all of them are well understood. Our study is the first attempt at presenting the opposite effects of an iso-BCFA (14-methylpentadecanoic acid, 14-MPA) and an anteiso-BCFA (12-methyltetradecanoic acid, 12-MTA) on selected genes related to fatty acid synthesis and inflammation: FASN, SREBP1, CRP, and IL-6 in the HepG2 cell line. We observed lowered expression of FASN, SREBP1, CRP, and IL-6 in cells treated with 14-MPA in comparison with control cells. In contrast, supplementation with 12-MTA caused opposite effects: increased mRNA levels of FASN, CRP, and IL-6. 12-MTA did not influence SREBP1 expression. The results of our preliminary study may suggest potential benefits of the supplementation of iso-BCFAs in obese patients, for inflammation and hypertriglyceridemia prevention.
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Affiliation(s)
- Paulina Gozdzik
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
| | - Aleksandra Czumaj
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
| | - Tomasz Sledzinski
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
| | - Adriana Mika
- Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland
- Department of Environmental Analysis, Faculty of Chemistry, University of Gdańsk, Wita Stwosza 63, 80-308 Gdańsk, Poland
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Likitnukul S, Thammacharoen S, Sriwatananukulkit O, Duangtha C, Hemstapat R, Sunrat C, Mangmool S, Pinthong D. Short-Term Growth Hormone Administration Mediates Hepatic Fatty Acid Uptake and De Novo Lipogenesis Gene Expression in Obese Rats. Biomedicines 2023; 11:biomedicines11041050. [PMID: 37189668 DOI: 10.3390/biomedicines11041050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/31/2023] Open
Abstract
Obesity has been linked to metabolic syndrome, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD). Obesity causes a decrease in growth hormone (GH) levels and an increase in insulin levels. Long-term GH treatment increased lipolytic activity as opposed to decreasing insulin sensitivity. Nonetheless, it is possible that short-term GH administration had no impact on insulin sensitivity. In this study, the effect of short-term GH administration on liver lipid metabolism and the effector molecules of GH and insulin receptors were investigated in diet-induced obesity (DIO) rats. Recombinant human GH (1 mg/kg) was then administered for 3 days. Livers were collected to determine the hepatic mRNA expression and protein levels involved in lipid metabolism. The expression of GH and insulin receptor effector proteins was investigated. In DIO rats, short-term GH administration significantly reduced hepatic fatty acid synthase (FASN) and cluster of differentiation 36 (CD36) mRNA expression while increasing carnitine palmitoyltransferase 1A (CPT1A) mRNA expression. Short-term GH administration reduced hepatic FAS protein levels and downregulated gene transcription of hepatic fatty acid uptake and lipogenesis, while increasing fatty acid oxidation in DIO rats. DIO rats had lower hepatic JAK2 protein levels but higher IRS-1 levels than control rats due to hyperinsulinemia. Our findings suggest that short-term GH supplementation improves liver lipid metabolism and may slow the progression of NAFLD, where GH acts as the transcriptional regulator of related genes.
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Liu L, Yang Y, Yang F, Lin Y, Liu K, Wang X, Zhang Y. A mechanistic investigation about hepatoxic effects of borneol using zebrafish. Hum Exp Toxicol 2023; 42:9603271221149011. [PMID: 36594174 DOI: 10.1177/09603271221149011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Except for clinical value, borneol is routinely used in food and cosmetics with seldom safety evaluation. To investigate its hepatoxicity, we exposed 3 dpf (days post fertilization) larval zebrafish to borneol at a gradient of concentrations (200-500 μM) for 3 days. Herein, our results revealed that high doses of borneol (300-500 μM) caused liver size decrease or lateral lobe absence. Borneol also seriously disturbed the hepatic protein metabolism presented with the increased activity of alanine aminotransferase (ALT) and lipid metabolism shown with the increased level of triglycerides (TG) and total cholesterol (TC). The lipid accumulation (oil red staining) was detected as well. Additionally, significant upregulation of genes was detected that related to oxidative stress, lipid anabolism, endoplasmic reticulum stress (ERS), and autophagy. Conversely, the lipid metabolism-related genes were markedly downregulated. Moreover, the changes in the superoxide dismutase activity and the level of glutathione and malondialdehyde raised the likelihood of lipid peroxidation. The outcomes indicated the involvement of oxidative stress, ERS, lipid metabolism, and autophagy in borneol-induced lipid metabolic disorder and hepatic injury. This study will provide a more comprehensive understanding of borneol hepatoxicity and the theoretical basis for the safe use of this compound.
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Affiliation(s)
- L Liu
- School of Pharmacy, 12412Changzhou University, Changzhou, China
| | - Y Yang
- School of Pharmacy, 12412Changzhou University, Changzhou, China.,Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - F Yang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Y Lin
- School of Pharmacy, 12412Changzhou University, Changzhou, China
| | - K Liu
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - X Wang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Y Zhang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
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Hu H, Sun N, Du H, He Y, Pan K, Liu X, Lu X, Wei J, Liao M, Duan C. Mouse promyelocytic leukemia zinc finger protein (PLZF) regulates hepatic lipid and glucose homeostasis dependent on SIRT1. Front Pharmacol 2022; 13:1039726. [PMID: 36438786 PMCID: PMC9684722 DOI: 10.3389/fphar.2022.1039726] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022] Open
Abstract
Previous studies have demonstrated that promyelocytic leukemia zinc finger protein (PLZF) promotes the expression of gluconeogenic genes and hepatic glucose output, which leads to hyperglycemia. However, the role played by PLZF in regulating lipid metabolism is not known. In this study, we aimed to examine the function of PLZF in regulating hepatic lipid and glucose homeostasis and the underlying mechanisms. The expression of PLZF was determined in different mouse models with regard to non-alcoholic fatty liver disease (NAFLD). In the next step, adenoviruses that express PLZF (Ad-PLZF) or PLZF-specific shRNA (Ad-shPLZF) were utilized to alter PLZF expression in mouse livers and in primary hepatocytes. For the phenotype of the fatty liver, histologic and biochemical analyses of hepatic triglyceride (TG), serum TG and cholesterol levels were carried out. The underlying molecular mechanism for the regulation of lipid metabolism by PLZF was further explored using luciferase reporter gene assay and ChIP analysis. The results demonstrated that PLZF expression was upregulated in livers derived from ob/ob, db/db and diet-induced obesity (DIO) mice. Liver PLZF-overexpressing C57BL/6J mice showed fatty liver phenotype, liver inflammation, impaired glucose tolerance and insulin sensitivity. On the other hand, hepatic PLZF knockdown in db/db and DIO mice alleviated hepatic steatosis. Of note, we found that PLZF activates SREBP-1c gene transcription through binding directly to the promoter fragment of this gene, which would induce a repressor-to-activator conversion depending on its interaction with SIRT1 in the role played by PLZF in the transcription process through deacetylation. Thus, PLZF is identified as an essential regulator of hepatic lipid and glucose metabolism, where the modulation of its liver expression could open up a therapeutic path for treating NAFLD.
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Affiliation(s)
- Huiling Hu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Nannan Sun
- Department of Obstetrics and Gynecology, Guangdong Provincial Key Laboratory of Major Obstetric Diseases, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou, China
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Haiyan Du
- Department of Hepatology, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Yuqing He
- Translational Medicine Research Center, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Kunyi Pan
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Xiuli Liu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Xiaoxia Lu
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Jie Wei
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- *Correspondence: Jie Wei, ; Mianmian Liao, ; Chaohui Duan,
| | - Mianmian Liao
- Department of Hepatology, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- *Correspondence: Jie Wei, ; Mianmian Liao, ; Chaohui Duan,
| | - Chaohui Duan
- Department of Clinical Laboratory, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
- *Correspondence: Jie Wei, ; Mianmian Liao, ; Chaohui Duan,
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Im ST, Kim HS, Jung WK, Lee SH. Ishophloroglucin A, a potent PTP1B inhibitor isolated from brown alga Ishige okamurae inhibits adipogenesis in 3T3-L1 adipocytes. Fitoterapia 2022; 163:105342. [PMID: 36330897 DOI: 10.1016/j.fitote.2022.105342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/23/2022] [Accepted: 10/23/2022] [Indexed: 11/28/2022]
Abstract
Ishophloroglucin A (IPA) is one of the most abundant and active compounds in Ishige okamurae and is known to be a potential therapeutic candidate for the improvement of metabolic diseases. However, IPA on the inhibitory effects of protein tyrosine phosphatase 1B (PTP1B) and adipogenesis have not been determined. In this study, we investigated the effects of IPA on the inhibition of PTP1B, the effects on adipogenesis, and its mechanisms of action in 3 T3-L1 adipocytes. The IC50 value of IPA against PTP1B was 0.43 μM, which evidenced the higher inhibition activity than that of ursolic acid, a known PTP1B inhibitor. For further insight, we predicted the 3D structure of PTP1B and used a docking algorithm to simulate the binding between PTP1B and IPA. Molecular docking studies revealed a high and stable binding affinity between IPA and PTP1B and indicated that the IPA could interacts with the amino acid residues located in a region to the active site of PTP1B. Further studies showed that IPA concentrations between 6.25 μM and 25 μM dose-dependently attenuated adipogenesis, which was accompanied by a reduction in adipogenesis-related factors, including PPARγ, C/EBPα, SREBP-1c, and FABP4. Our findings suggested that IPA may be a promising natural compound for the treatment of obesity and related diseases.
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Affiliation(s)
- Seung Tae Im
- Department of Medical Science, Soonchunhyang University, Asan 31538, Republic of Korea
| | - Hyun-Soo Kim
- National Marine Biodiversity Institute of Korea, Seocheon 33662, Republic of Korea
| | - Won-Kyo Jung
- Major of Biomedical Engineering, Division of Smart Healthcare and New-senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Republic of Korea; Research Center for Marine-Integrated Bionics Technology and Marine Integrated Biomedical Technology Center, Pukyong National University, Busan 48513, Republic of Korea.
| | - Seung-Hong Lee
- Department of Medical Science, Soonchunhyang University, Asan 31538, Republic of Korea; Department of Pharmaceutical Engineering, Soonchunhyang University, Asan 31538, Republic of Korea.
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Li C, Zhang C, Zhu C, Zhang J, Xia Q, Liu K, Zhang Y. Inflammation aggravated the hepatotoxicity of triptolide by oxidative stress, lipid metabolism disorder, autophagy, and apoptosis in zebrafish. Front Pharmacol 2022; 13:949312. [PMID: 36110530 PMCID: PMC9468416 DOI: 10.3389/fphar.2022.949312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/02/2022] [Indexed: 11/25/2022] Open
Abstract
Triptolide is a major compound isolated from the Tripterygium wilfordii Hook that is mainly used for the treatment of autoimmune disorders and inflammatory diseases. Though triptolide-induced hepatotoxicity has been widely reported, the hepatic effects when the patients are in an inflammatory state are not clear. In this study, we used low-dose Lipopolysaccharides (LPS) to disrupt the inflammation homeostasis in the liver of zebrafish and explored the hepatotoxicity of triptolide under an inflammatory state. Compared with the Triptolide group, LPS-Triptolide cotreatment exacerbate the liver injury with a remarkable decrease of liver size and liver-specific fluorescence intensity, accompanied by significant elevation of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. Liver cell damages were further demonstrated by histological staining and scanning electron microscopy observation. Lipid metabolism was severely impaired as indicated by delayed yolk sac absorption, accumulated triglycerides in the liver, and dysregulation of the related genes, such as ppar-α, cpt-1, mgst, srebf1/2, and fasn. Oxidative stress could be involved in the molecular mechanism as the Nrf2/keap1 antioxidant pathways were down-regulated when the zebrafish in an inflammatory state. Moreover, the expression of autophagy-related genes such as beclin, atg5, map1lc3b, and atg3 was also dysregulated. Finally, apoptosis was significantly induced in responses to LPS-Triptolide co-treatment. We speculate that triptolide could exacerbate the immune response and impair lipid metabolism, resulting in enhanced sensitivity of the zebrafish liver to triptolide-induced toxic effects through disruption of the antioxidant system and induction of apoptosis.
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Affiliation(s)
- Chenqinyao Li
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
| | - Changqing Zhang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
- Key Laboratory of Birth Regulation and Control Technology of National Health Commission of China, Shandong Provincial Maternal and Child Health Care Hospital, Jinan, China
| | - Chengyue Zhu
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
| | - Jie Zhang
- State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
| | - Qing Xia
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
| | - Kechun Liu
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
| | - Yun Zhang
- Biology Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, China
- Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province, Jinan, China
- *Correspondence: Yun Zhang,
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9
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Mei Y, Hu H, Deng L, Sun X, Tan W. Isosteviol sodium attenuates high fat/high cholesterol-induced myocardial dysfunction by regulating the Sirt1/AMPK pathway. Biochem Biophys Res Commun 2022; 621:80-87. [PMID: 35810595 DOI: 10.1016/j.bbrc.2022.06.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/14/2022] [Indexed: 11/02/2022]
Abstract
A fat-rich diet triggers obesity, and promotes cardiomyocyte injury. Till now, no prior investigations suggested a beneficial role of Isosteviol Sodium (STVNa) in cardiac activity in high fat diet (HFD)-exposed obese rats. However, there is evidence that STVNa accelerates healing of multiple tissue injuries. Herein, we explored the underlying mechanism behind the STVNa-based protection against HFD-induced myocardial dysfunction (MCD) in a rat model of myocardial injury. We employed dosages of 1, 10, and 20 mg/kg STVNa to treat MCD in rats fed with a HFD. Based on our results, STVNa repressed MCD (as indicated by ecocardiographic analysis), myocardium function, pathological structure, and myocardial enzymes. Mechanistically, the STVNa-mediated protection against HFD-induced MCD involved inhibition of inflammation and oxidative stress. Furthermore, using Western blot analysis, we revealed that the critical members of the Sirt1/AMPK network were markedly activated in the STVNa-treated group, relative to HFD-fed controls. Collectively, these evidences suggested that the STVNa offered strong protection against HFD-induced MCD. Moreover, this effect was mediated by the activation of the Sirt1/AMPK network, which, in turn, promoted lipid metabolism.
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Affiliation(s)
- Ying Mei
- School of Pharmacy, Jinan University, Guangzhou, 510632, China; YZ Health-tech Inc, Hengqin District, Zhuhai, 519000, China
| | - Hui Hu
- Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, 510006, China
| | - Liangjun Deng
- Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, 510006, China
| | - Xiaoou Sun
- Institute of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Wen Tan
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, 47500, Malaysia.
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10
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Li Z, Ji BW, Dixit PD, Tchourine K, Lien EC, Hosios AM, Abbott KL, Rutter JC, Westermark AM, Gorodetsky EF, Sullivan LB, Vander Heiden MG, Vitkup D. Cancer cells depend on environmental lipids for proliferation when electron acceptors are limited. Nat Metab 2022; 4:711-723. [PMID: 35739397 DOI: 10.1038/s42255-022-00588-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 05/17/2022] [Indexed: 01/31/2023]
Abstract
Production of oxidized biomass, which requires regeneration of the cofactor NAD+, can be a proliferation bottleneck that is influenced by environmental conditions. However, a comprehensive quantitative understanding of metabolic processes that may be affected by NAD+ deficiency is currently missing. Here, we show that de novo lipid biosynthesis can impose a substantial NAD+ consumption cost in proliferating cancer cells. When electron acceptors are limited, environmental lipids become crucial for proliferation because NAD+ is required to generate precursors for fatty acid biosynthesis. We find that both oxidative and even net reductive pathways for lipogenic citrate synthesis are gated by reactions that depend on NAD+ availability. We also show that access to acetate can relieve lipid auxotrophy by bypassing the NAD+ consuming reactions. Gene expression analysis demonstrates that lipid biosynthesis strongly anti-correlates with expression of hypoxia markers across tumor types. Overall, our results define a requirement for oxidative metabolism to support biosynthetic reactions and provide a mechanistic explanation for cancer cell dependence on lipid uptake in electron acceptor-limited conditions, such as hypoxia.
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Affiliation(s)
- Zhaoqi Li
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Brian W Ji
- Department of Systems Biology, Columbia University, New York, NY, USA
- Physician-Scientist Training Pathway, Department of Medicine, University of California, San Diego, San Diego, CA, USA
| | - Purushottam D Dixit
- Department of Systems Biology, Columbia University, New York, NY, USA
- Department of Physics, University of Florida, Gainesville, FL, USA
- University of Florida Genetics Institute, University of Florida, Gainesville, FL, USA
- Department of Chemical Engineering, University of Florida, Gainesville, FL, USA
- University of Florida Cancer Center, University of Florida, Gainesville, FL, USA
| | | | - Evan C Lien
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Aaron M Hosios
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Keene L Abbott
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Justine C Rutter
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Health Sciences and Technology (HST) and Harvard/MIT MD-PhD Program, Harvard Medical School, Boston, MA, USA
| | - Anna M Westermark
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Elizabeth F Gorodetsky
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Lucas B Sullivan
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
- Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Matthew G Vander Heiden
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Dana-Farber Cancer Institute, Boston, MA, USA.
| | - Dennis Vitkup
- Department of Systems Biology, Columbia University, New York, NY, USA.
- Department of Biomedical Informatics, Columbia University, New York, NY, USA.
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11
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Supplementation of Enriched Polyunsaturated Fatty Acids and CLA Cheese on High Fat Diet: Effects on Lipid Metabolism and Fat Profile. Foods 2022; 11:foods11030398. [PMID: 35159548 PMCID: PMC8834222 DOI: 10.3390/foods11030398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 12/13/2022] Open
Abstract
Epidemiological studies have demonstrated a positive relationship between dietary fat intake and the onset of several metabolic diseases. This association is particularly evident in a diet rich in saturated fatty acids, typical of animal foods, such as dairy products. However, these foods are the main source of fatty acids with a proven nutraceutical effect, such as the ω-3 fatty acid α-linolenic acid (ALA) and the conjugated linoleic acid (CLA), which have demonstrated important roles in the prevention of various diseases. In the present study, the effect of a supplementation with cheese enriched with ω-3 fatty acids and CLA on the metabolism and lipid profiles of C57bl/6 mice was evaluated. In particular, the analyses were conducted on different tissues, such as liver, muscle, adipose tissue and brain, known for their susceptibility to the effects of dietary fats. Supplementing cheese enriched in CLA and ω-3 fats reduced the level of saturated fat and increased the content of CLA and ALA in all tissues considered, except for the brain. Furthermore, the consumption of this cheese resulted in a tissue-specific response in the expression levels of genes involved in lipid and mitochondrial metabolism. As regards genes involved in the inflammatory response, the consumption of enriched cheese resulted in a reduction in the expression of inflammatory genes in all tissues analyzed. Considering the effects that chronic inflammation associated with a high-calorie and high-fat diet (meta-inflammation) or aging (inflammaging) has on the onset of chronic degenerative diseases, these data could be of great interest as they indicate the feasibility of modulating inflammation (thus avoiding/delaying these pathologies) with a nutritional and non-pharmacological intervention.
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12
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Chronic exposure to nonylphenol induces oxidative stress and liver damage in male zebrafish (Danio rerio): Mechanistic insight into cellular energy sensors, lipid accumulation and immune modulation. Chem Biol Interact 2022; 351:109762. [PMID: 34843692 DOI: 10.1016/j.cbi.2021.109762] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/06/2021] [Accepted: 11/25/2021] [Indexed: 02/07/2023]
Abstract
Nonylphenol (NP), an environmentally persistent and toxic endocrine-disrupting chemical with estrogenic properties, has severe implications on humans and wildlife. Accumulating evidence demonstrates the toxic response of NP on the developmental process, nervous system, and reproductive parameters. Although NP exposure has been implicated in chronic liver injury, the underlying events associated with hepatic pathophysiology remain less investigated. Using male zebrafish (Danio rerio) as the model, the present study investigates the impact of environmentally relevant concentrations of NP (50 and 100 μg/L, 21 days) on hepatic redox homeostasis vis-à-vis cellular energy sensors, inflammatory response, and cell death involving a mechanistic insight into estrogen receptor (ER) modulation. Our results demonstrate that congruent with significant alteration in transcript abundance of antioxidant enzymes (SOD1, SOD2, Catalase, GPx1a, GSTα1), chronic exposure to NP promotes ROS synthesis, more specifically superoxide anions and H2O2 levels, and lipid peroxidation potentially through elevated NOX4 expression. Importantly, NP perturbation of markers associated with fatty acid biosynthesis (srebf1/fasn) and cellular energy-sensing network (sirt1/ampkα/pgc1α) indicates dysregulated energy homeostasis, metabolic disruption, and macrovesicular steatosis, albeit with differential sensitivity at the dose level tested. Besides, elevated p38-MAPK phosphorylation (activation) together with loss of ER homeostasis at both mRNA (esr1, esr2a, esr2b) and protein (ERα, ERβ) levels suggest that NP modulation of ER abundance may have a significant influence on hepatic events. Elevated expression of inflammatory markers (TLR4, p-NF-κB, TNF-α, IL-6, IL-1β, and NOS2) and pro-apoptotic and necrotic regulators, e.g., Bax, caspase- 8, -9 and cleaved PARP1 (50 kDa), indicate chronic inflammation and hepatotoxicity in NP-exposed males. Collectively, elevated oxidative stress, metabolic dysregulation and immune modulation may lead to chronic liver injury in organisms exposed to metabolic disrupting chemicals.
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13
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Rondini EA, Ramseyer VD, Burl RB, Pique-Regi R, Granneman JG. Single cell functional genomics reveals plasticity of subcutaneous white adipose tissue (WAT) during early postnatal development. Mol Metab 2021; 53:101307. [PMID: 34298199 PMCID: PMC8385178 DOI: 10.1016/j.molmet.2021.101307] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/09/2021] [Accepted: 07/16/2021] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE The current study addresses the cellular complexity and plasticity of subcutaneous (inguinal) white adipose tissue (iWAT) in mice during the critical periods of perinatal growth and establishment. METHODS We performed a large-scale single cell transcriptomic (scRNA-seq) and epigenomic (snATAC-seq) characterization of cellular subtypes (adipose stromal cells (ASC) and adipocyte nuclei) during inguinal WAT (subcutaneous; iWAT) development in mice, capturing the early postnatal period (postnatal days (PND) 06 and 18) through adulthood (PND56). RESULTS Perinatal and adult iWAT contain 3 major ASC subtypes that can be independently identified by RNA expression profiles and DNA transposase accessibility. Furthermore, the transcriptomes and enhancer landscapes of both ASC and adipocytes dynamically change during postnatal development. Perinatal ASC (PND06) are highly enriched for several imprinted genes (IGs; e.g., Mest, H19, Igf2) and extracellular matrix proteins whose expression then declines prior to weaning (PND18). By comparison, adult ASC (PND56) are more enriched for transcripts associated with immunoregulation, oxidative stress, and integrin signaling. Two clusters of mature adipocytes, identified through single nuclei RNA sequencing (snRNA-seq), were distinctive for proinflammatory/immune or metabolic gene expression patterns that became more transcriptionally diverse in adult animals. Single nuclei assay for transposase-accessible chromatin (snATAC-seq) revealed that differences in gene expression were associated with developmental changes in chromatin accessibility and predicted transcription factor motifs (e.g., Plagl1, Ar) in both stromal cells and adipocytes. CONCLUSIONS Our data provide new insights into transcriptional and epigenomic signaling networks important during iWAT establishment at a single cell resolution, with important implications for the field of metabolic programming.
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Affiliation(s)
- Elizabeth A Rondini
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA
| | - Vanesa D Ramseyer
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA
| | - Rayanne B Burl
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA
| | - Roger Pique-Regi
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA
| | - James G Granneman
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, USA; Center for Integrative Metabolic and Endocrine Research, Wayne State University, Detroit, MI, USA.
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14
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Zhang Y, Fan X, Qiu L, Zhu W, Huang L, Miao Y. Liver X receptor α promotes milk fat synthesis in buffalo mammary epithelial cells by regulating the expression of FASN. J Dairy Sci 2021; 104:12980-12993. [PMID: 34593221 DOI: 10.3168/jds.2021-20596] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 08/16/2021] [Indexed: 01/14/2023]
Abstract
Liver X receptor α (LXRα; NR1H3) is an important transcription factor that can facilitate milk fat synthesis by regulating the transcription of FASN in mice and goats. Nevertheless, the lipid synthesis related to LXRα and its regulation on FASN in the buffalo mammary gland remain elusive. Here, we demonstrated that the mRNA and protein expression of LXRα in buffalo mammary tissue increased in lactation compared with that in the dry-off period. Overexpression of NR1H3 enhanced the lipid droplet formation and triacylglycerol concentration in buffalo mammary epithelial cells (BuMEC), whereas the knockdown of NR1H3 resulted in a decrease in the number of lipid droplets. At the same time, NR1H3 also affected the expression of regulatory factors (INSIG1, INSIG2, SREBF1, and PPARG) related to milk fat synthesis and that of genes involved in de novo synthesis (FASN, ACACA, and SCD), and uptake and transport (LPL, CD36, and FABP3) of fatty acids as well as triacylglycerol synthesis (GPAM, APGAT6, and DGAT1). Luciferase reporter assays indicated that overexpression of NR1H3 resulted in an increase in the activity of FASN promoter, whereas the knockdown of NR1H3 had an opposite effect. When NR1H3 was overexpressed, mutations in LXRE or SRE could decrease the promoter activity of FASN. Furthermore, mutagenesis of both LXRE and SRE within the FASN promoter completely eliminated the induced activity of LXRα. Our results reveal that buffalo LXRα promotes milk fat synthesis through regulating the expression of FASN by directly interacting with FASN promoter and affecting the SREBF1 expression. This study underscores a crucial role of LXRα in regulating lipid synthesis of the buffalo mammary gland.
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Affiliation(s)
- Yongyun Zhang
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China; Teaching Demonstration Center of the Basic Experiments of Agricultural Majors, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Xinyang Fan
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Lihua Qiu
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Wei Zhu
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Lige Huang
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China
| | - Yongwang Miao
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China.
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15
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Bhattarai A, Likos EM, Weyman CM, Shukla GC. Regulation of cholesterol biosynthesis and lipid metabolism: A microRNA management perspective. Steroids 2021; 173:108878. [PMID: 34174291 DOI: 10.1016/j.steroids.2021.108878] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 06/07/2021] [Accepted: 06/11/2021] [Indexed: 12/14/2022]
Abstract
Cellular disruption of lipid and cholesterol metabolism results in pathological processes linked to metabolic and cardiovascular diseases. Classically, at the transcription stages, the Cholesterol levels are controlled by two cellular pathways. First, the SREBP transcription factor family controls Cholesterol biosynthesis via transcriptional regulation of critical rate-limiting cholesterogenic and lipogenic proteins. Secondly, The LXR/RXR transcription factor family controls cholesterol shuttling via transcriptional regulation of cholesterol transport proteins. In addition, the posttranscriptional control of gene expression of various enzymes and proteins of cholesterol biosynthesis pathways is mediated by small non-coding microRNAs. Regulatory noncoding miRNAs are critical regulators of biological processes, including developmental and metabolic functions. miRNAs function to fine-tune lipid and cholesterol metabolism pathways by controlling the mRNA levels and translation of critical molecules in each pathway. This review discusses the regulatory roles of miRNAs in cholesterol and lipid metabolism via direct and indirect effects on their target genes, including SREBP, LXR, HDL, LDL, and ABCA transporters. We also discuss the therapeutic implications of miRNA functions and their purported role in the potentiation of small molecule therapies.
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Affiliation(s)
- Asmita Bhattarai
- Center for Gene Regulation, Department of Biological, Geo and EVS Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44114, USA
| | - Eviania M Likos
- Center for Gene Regulation, Department of Biological, Geo and EVS Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44114, USA
| | - Crystal M Weyman
- Center for Gene Regulation, Department of Biological, Geo and EVS Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44114, USA
| | - Girish C Shukla
- Center for Gene Regulation, Department of Biological, Geo and EVS Sciences, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44114, USA
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16
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You YN, Xing QQ, Zhao X, Ji JJ, Yan H, Zhou T, Dong YM, Ren LS, Hou ST, Ding YY. Gu-Ben-Fang-Xiao decoction modulates lipid metabolism by activating the AMPK pathway in asthma remission. Biomed Pharmacother 2021; 138:111403. [PMID: 33714782 DOI: 10.1016/j.biopha.2021.111403] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 02/01/2021] [Accepted: 02/09/2021] [Indexed: 02/06/2023] Open
Abstract
Gu-Ben-Fang-Xiao decoction (GBFXD), derived from the traditional Chinese medicine Yu-Ping-Feng-San, is widely used in clinical settings and has obvious curative effects in respiratory diseases. GBFXD regulates cholesterol transport and lipid metabolism in chronic persistent asthma. There is evidence for its beneficial effects in the remission stage of asthma; however, its metabolic regulatory effects and underlying mechanisms during asthma remission are unclear. In the present study, we used liquid chromatography-mass spectrometry (LC-MS) to analyse the metabolic profile of mouse serum during asthma remission. The acquired LC-MS data were subjected to a multivariate analysis for identification of significantly altered metabolites. In total, 42 metabolites were significantly differentially expressed among the control, model, and GBFXD groups. In particular, levels of fatty acids, acylcarnitines, phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, triglycerides, and diacylglycerols were altered during asthma remission. GBFXD may maintain lipid homeostasis on the lung surface by modulating lipid metabolism and may thereby alleviate asthma. We further quantified hypogeic acid (FA 16:1) based on targeted metabolomics and found that GBFXD may regulate fatty acid metabolism by activating the AMP-activated protein kinase (AMPK) pathway. These results support the use of GBFXD in patients with asthma remission.
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Affiliation(s)
- Yan-Nan You
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Qiong-Qiong Xing
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Xia Zhao
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Jian-Jian Ji
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Hua Yan
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Tao Zhou
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China
| | - Ying-Mei Dong
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Li-Shun Ren
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Shu-Ting Hou
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Yuan-Yuan Ding
- Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, China; Pediatric Institution of Nanjing University of Chinese Medicine, Nanjing 210023, China; Jiangsu Key Laboratory of Pediatric Respiratory Disease, Nanjing 210023, China; Medical Metabolomics Center, Nanjing University of Chinese Medicine, Nanjing 210023, China
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17
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Chua NK, Coates HW, Brown AJ. Squalene monooxygenase: a journey to the heart of cholesterol synthesis. Prog Lipid Res 2020; 79:101033. [DOI: 10.1016/j.plipres.2020.101033] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/21/2020] [Accepted: 04/24/2020] [Indexed: 02/07/2023]
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18
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Liu M, Zhang G, Wu S, Song M, Wang J, Cai W, Mi S, Liu C. Schaftoside alleviates HFD-induced hepatic lipid accumulation in mice via upregulating farnesoid X receptor. JOURNAL OF ETHNOPHARMACOLOGY 2020; 255:112776. [PMID: 32205261 DOI: 10.1016/j.jep.2020.112776] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 03/06/2020] [Accepted: 03/17/2020] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGY RELEVANCE The farnesoid X receptor (FXR) is a therapeutic target of for the treatment of non-alcoholic fatty liver disease (NAFLD) owing to its regulatory role in lipid homeostasis. Schaftoside (SS) is a bioactive compound of Herba Desmodii Styracifolii, which has traditionally been used to treat hepatitis and cholelithiasis. However, the potential hepatoprotective effect of SS against NAFLD and the underlying mechanisms remain unknown. AIM OF THE STUDY We investigated whether SS could improve NAFLD-induced liver injury by decreasing lipid accumulation via the activation of FXR signalling. MATERIALS AND METHODS In vivo, the effects of SS on high-fat diet (HFD)-induced lipid accumulation in the liver of mice were evaluated by serum biochemical parameters and histopathological analysis. In vitro, the intracellular triglyceride (TG) level and Oil Red O staining were used to evaluate the lipid removal ability of SS in Huh-7 cells or FXR knockout mouse primary hepatocytes (MPHs) induced by oleic acid (OA). Moreover, FXR/sterol regulatory element-binding protein 1 (SREBP1) mRNA and protein expression levels were detected. RESULTS SS reduced HFD-induced lipid accumulation in the liver, as indicated by decreased aspartate aminotransferase (AST), cholesterol (Ch), and TG levels in serum and TG levels in liver tissue, and subsequently resulting in attenuation of liver histopathological injury. Gene expression profiles demonstrated that SS dose-dependently prevented HFD-induced decrease of FXR expression and inversely inhibited SREBP1 expression in the nucleus. Furthermore, SS significantly suppressed excessive TG accumulation and decreased intracellular TG level in Huh-7 cells or MPHs via the upregulation of FXR and inhibition of SREBP1 expression in the nucleus. CONCLUSION Our results suggest that SS ameliorates HFD-induced NAFLD by the decrease of lipid accumulation via the control of FXR-SREBP1 signalling.
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Affiliation(s)
- Meijing Liu
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100191, China; School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Guohui Zhang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China; Zhuhai Precision Medicine Center, Zhuhai People's Hospital, Zhuhai, 519000, China
| | - Shuangcheng Wu
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Meng Song
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Jueyu Wang
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Weibin Cai
- Guangdong Second Traditional Chinese Medicine Hospital, Guangzhou University of Chinese Medicine, Guangzhou, 510095, China
| | - Suiqing Mi
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China
| | - Changhui Liu
- School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510405, China.
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19
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Viscarra J, Sul HS. Epigenetic Regulation of Hepatic Lipogenesis: Role in Hepatosteatosis and Diabetes. Diabetes 2020; 69:525-531. [PMID: 32198196 PMCID: PMC7085244 DOI: 10.2337/dbi18-0032] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 01/23/2020] [Indexed: 12/31/2022]
Abstract
Hepatosteatosis, which is frequently associated with development of metabolic syndrome and insulin resistance, manifests when triglyceride (TG) input in the liver is greater than TG output, resulting in the excess accumulation of TG. Dysregulation of lipogenesis therefore has the potential to increase lipid accumulation in the liver, leading to insulin resistance and type 2 diabetes. Recently, efforts have been made to examine the epigenetic regulation of metabolism by histone-modifying enzymes that alter chromatin accessibility for activation or repression of transcription. For regulation of lipogenic gene transcription, various known lipogenic transcription factors, such as USF1, ChREBP, and LXR, interact with and recruit specific histone modifiers, directing specificity toward lipogenesis. Alteration or impairment of the functions of these histone modifiers can lead to dysregulation of lipogenesis and thus hepatosteatosis leading to insulin resistance and type 2 diabetes.
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Affiliation(s)
- Jose Viscarra
- Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, CA
| | - Hei Sook Sul
- Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, CA
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20
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Histone demethylase JMJD1C is phosphorylated by mTOR to activate de novo lipogenesis. Nat Commun 2020; 11:796. [PMID: 32034158 PMCID: PMC7005700 DOI: 10.1038/s41467-020-14617-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 01/20/2020] [Indexed: 01/28/2023] Open
Abstract
Fatty acid and triglyceride synthesis increases greatly in response to feeding and insulin. This lipogenic induction involves coordinate transcriptional activation of various enzymes in lipogenic pathway, including fatty acid synthase and glycerol-3-phosphate acyltransferase. Here, we show that JMJD1C is a specific histone demethylase for lipogenic gene transcription in liver. In response to feeding/insulin, JMJD1C is phosphorylated at T505 by mTOR complex to allow direct interaction with USF-1 for recruitment to lipogenic promoter regions. Thus, by demethylating H3K9me2, JMJD1C alters chromatin accessibility to allow transcription. Consequently, JMJD1C promotes lipogenesis in vivo to increase hepatic and plasma triglyceride levels, showing its role in metabolic adaption for activation of the lipogenic program in response to feeding/insulin, and its contribution to development of hepatosteatosis resulting in insulin resistance. In response to insulin, liver cells increase de novo lipogenesis via the transcription factors USF-1 and SREBP. Here the authors show that USF-1 recruits JMJD1C, after its phosphorylation by mTOR, to lipogenic promoters where JMJD1C demethylates histone H3, contributing to lipogenesis by an epigenetic mechanism.
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Shirouchi B, Yanagi S, Okawa C, Koga M, Sato M. 6-Ketocholestanol suppresses lipid accumulation by decreasing FASN gene expression through SREBP-dependent regulation in HepG2 cells. Cytotechnology 2020; 72:175-187. [PMID: 31933103 DOI: 10.1007/s10616-019-00368-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/30/2019] [Indexed: 12/20/2022] Open
Abstract
Nuclear receptors, such as liver X receptors (LXRs) and sterol regulatory element-binding proteins (SREBPs), are key regulators of lipogenic genes, including fatty acid synthase (FASN). It has been reported that several oxycholesterols (OCs) act as LXR ligands; however, it is unclear whether all OC molecular species act as ligands. We previously demonstrated that the absorption rate of dietary 6-ketocholestanol (6-keto), an oxycholesterol, is the highest of all the OCs using thoracic lymph duct-cannulated rats. However, limited information is available about the physiological significance of 6-keto. In this study, we investigated whether treatment with 6-keto increases intracellular triacylglycerol (TAG) levels through up-regulation of lipogenic gene expression in HepG2 cells. 6-Keto treatment significantly reduced intracellular TAG levels through down-regulation of lipogenic genes including FASN. Although 6-keto significantly suppressed FASN gene promoter activities, the action was completely diminished when mutations were present in the SREBP promoter site. TO901317 (TO) significantly increased FASN gene promoter activities, whereas simultaneous treatment with TO and 6-keto significantly reduced this activity. We also compared the effects of several OCs that are oxidized at the carbon-6 and -7 in the B-ring of cholesterol on FASN gene promoter activities. Similar to 6-keto, 6α-OH and 6β-OH significantly reduced the activity of the FASN gene promoter, which suggests that oxidation of carbon-6 in the B-ring may play an important role in the reduction of FASN expression. Our results indicate that 6-keto suppresses lipid accumulation by decreasing FASN gene expression through SREBP-dependent regulation in HepG2 cells.
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Affiliation(s)
- Bungo Shirouchi
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Shuhei Yanagi
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Chinami Okawa
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Maiko Koga
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Masao Sato
- Laboratory of Nutrition Chemistry, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
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Chen XY, Cai CZ, Yu ML, Feng ZM, Zhang YW, Liu PH, Zeng H, Yu CH. LB100 ameliorates nonalcoholic fatty liver disease via the AMPK/Sirt1 pathway. World J Gastroenterol 2019; 25:6607-6618. [PMID: 31832001 PMCID: PMC6906208 DOI: 10.3748/wjg.v25.i45.6607] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/10/2019] [Accepted: 11/22/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND It is well known that nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR). LB100, a serine/threonine protein phosphatase 2A (PP2A) inhibitor, is closely related to IR. However, there is little data regarding its direct influence on NAFLD.
AIM To elucidate the effect and underlying mechanism of LB100 in NAFLD.
METHODS After 10 wk of high fat diet (HFD) feeding, male C57BL/6 mice were injected intraperitoneally with vehicle or LB100 for an additional 6 wk (three times a week). The L02 cell line was treated with LB100 and free fatty acids (FFAs) for 24 h. Hematoxylin and eosin and oil red O staining were performed for histological examination. Western blot analysis was used to detect the protein expression of Sirtuin 1 (Sirt1), total and phosphorylated AMP-activated protein kinase α (AMPKα), and the proteins involved in lipogenesis and fatty acid oxidation. The mRNA levels were determined by qPCR. Pharmacological inhibition of AMPK was performed to further examine the exact mechanism of LB100 in NAFLD.
RESULTS LB100 significantly ameliorated HFD-induced obesity, hepatic lipid accumulation and hepatic injury in mice. In addition, LB100 significantly downregulated the protein levels of acetyl-CoA carboxylase, sterol regulatory element-binding protein 1 and its lipogenesis target genes, including stearoyl-CoA desaturase-1 and fatty acid synthase, and upregulated the levels of proteins involved in fatty acid β-oxidation, such as peroxisome proliferator-activated receptor α (PPARα), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), carnitine palmitoyltransferase 1α, acyl-CoA oxidase 1 and uncoupling protein 2, as well as the upstream mediators Sirt1 and AMPKα in the livers of HFD-fed mice. In vitro, LB100 alleviated FFA-induced lipid accumulation in L02 cells through the AMPK/Sirt1 signaling pathway. Further studies showed that the curative effect of LB100 on lipid accumulation was abolished by inhibiting AMPKα in L02 cells.
CONCLUSION PP2A inhibition by LB100 significantly ameliorates hepatic steatosis by regulating hepatic lipogenesis and fatty acid oxidation via the AMPK/Sirt1 pathway. LB100 may be a potential therapeutic agent for NAFLD.
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Affiliation(s)
- Xue-Yang Chen
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Chang-Zhou Cai
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Meng-Li Yu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Ze-Min Feng
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Yu-Wei Zhang
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Pei-Hao Liu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Hang Zeng
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
| | - Chao-Hui Yu
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, Zhejiang Province, China
- Clinical Research Center for Hepatobiliary and Pancreatic Diseases of Zhejiang Province, Hangzhou 310003, Zhejiang Province, China
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23
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SPIN1 triggers abnormal lipid metabolism and enhances tumor growth in liver cancer. Cancer Lett 2019; 470:54-63. [PMID: 31790762 DOI: 10.1016/j.canlet.2019.11.032] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/24/2019] [Accepted: 11/25/2019] [Indexed: 11/22/2022]
Abstract
Abnormal lipid metabolism plays crucial roles in the development of cancer. Spindlin 1 (SPIN1) involving the process of spindle organization and chromosomal stability serves as an important player in the carcinogenesis. In this study, we try to identify the new function of SPIN1 in lipid metabolism of liver cancer. Tissue microarray showed that 75% (60/80) of hepatocellular carcinoma (HCC) tissues were positive for SPIN1, which was highly expressed in clinical HCC samples and positively associated with malignancy of HCC. Strikingly, SPIN1 could modulate abnormal lipid metabolism by increasing intracellular triglycerides, cholesterols, and lipid droplets in hepatoma cells, which could remarkably enhance the proliferation of hepatoma cells. Mechanistically, SPIN1 up-regulated FASN in hepatoma cells. SPIN1 co-activated transcriptional factor SREBP1c in the promoter of FASN through interaction with SREBP1c. Moreover, SPIN1 promoted the growth of liver cancer in vitro and in vivo and the levels of intracellular triglycerides, cholesterols and lipid droplets were increased in the tumor tissues from mice. In conclusion, SPIN1 modulates abnormal lipid metabolism and enhances growth of liver cancer through SREBP1c-triggered FASN signaling. Therapeutically, SPIN1 may serve as a novel target for HCC.
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24
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Lee G, Jang H, Kim YY, Choe SS, Kong J, Hwang I, Park J, Im SS, Kim JB. SREBP1c-PAX4 Axis Mediates Pancreatic β-Cell Compensatory Responses Upon Metabolic Stress. Diabetes 2019; 68:81-94. [PMID: 30352876 DOI: 10.2337/db18-0556] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 10/03/2018] [Indexed: 11/13/2022]
Abstract
SREBP1c is a key transcription factor for de novo lipogenesis. Although SREBP1c is expressed in pancreatic islets, its physiological roles in pancreatic β-cells are largely unknown. In this study, we demonstrate that SREBP1c regulates β-cell compensation under metabolic stress. SREBP1c expression level was augmented in pancreatic islets from obese and diabetic animals. In pancreatic β-cells, SREBP1c activation promoted the expression of cell cycle genes and stimulated β-cell proliferation through its novel target gene, PAX4 Compared with SREBP1c+/+ mice, SREBP1c-/- mice showed glucose intolerance with low insulin levels. Moreover, β-cells from SREBP1c-/- mice exhibited reduced capacity to proliferate and secrete insulin. Conversely, transplantation of SREBP1c-overexpressing islets restored insulin levels and relieved hyperglycemia in streptozotocin-induced diabetic animals. Collectively, these data suggest that pancreatic SREBP1c is a key player in mediating β-cell compensatory responses in obesity.
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Affiliation(s)
- Gung Lee
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Hagoon Jang
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Ye Young Kim
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Sung Sik Choe
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jinuk Kong
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Injae Hwang
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Jeu Park
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
| | - Seung-Soon Im
- Department of Physiology and Medical Research Center, Keimyung University School of Medicine, Daegu, Republic of Korea
| | - Jae Bum Kim
- National Creative Research Initiatives Center for Adipose Tissue Remodeling, Institute of Molecular Biology and Genetics, Department of Biological Sciences, Seoul National University, Seoul, South Korea
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Luo Y, Zhang X, Zhu Z, Jiao N, Qiu K, Yin J. Surplus dietary isoleucine intake enhanced monounsaturated fatty acid synthesis and fat accumulation in skeletal muscle of finishing pigs. J Anim Sci Biotechnol 2018; 9:88. [PMID: 30598820 PMCID: PMC6302484 DOI: 10.1186/s40104-018-0306-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 11/07/2018] [Indexed: 01/04/2023] Open
Abstract
Background Isoleucine (Ile) has been implicated in the regulation of energy homeostasis and adipogenesis. However, the impact of surplus dietary Ile intake on muscle lipogenesis remains unknown. The present study aimed to investigate the impact of dietary supplementation of extra-Ile on lipogenesis, fatty acid profile and lipid accumulation in skeletal muscle in finishing pigs. Methods Forty-eight barrows with initial body weight of 77.0 ± 0.1 kg were allotted to one of two groups and fed diets containing 0.39%, 0.53% standardized ileal digestible (SID) Ile with six replicates per treatment and four pigs per replicate for 30 d. Results Dietary Ile intake significantly improved the intramuscular fat (IMF) content and monounsaturated fatty acid (MUFA) concentration in the skeletal muscle (P < 0.05), and decreased the drip loss and shear force (P < 0.05) without influencing the growth performance of pigs (P > 0.05). Moreover, the phosphorylation of adenosine monophosphate activated protein kinase α (AMPKα) and acetyl coenzyme A carboxylase (ACC) proteins that monitor lipid metabolism were decreased in skeletal muscle of pigs offered extra-Ile diet (P < 0.05). The mRNA expression of adipose-specific genes adipocyte determination and differentiation factor 1 (ADD1), fatty acid synthase (FAS), and stearoyl-CoA desaturase (SCD) were upregulated and the activity of SCD was increased as well (P < 0.05). Conclusions Surplus dietary Ile intake could increase IMF accumulation and MUFA synthesis in skeletal muscle through depressing the phosphorylation of AMPKα-ACC and stimulating the expression and activity of SCD, and increasing the capability of lipogenesis in skeletal muscle. Electronic supplementary material The online version of this article (10.1186/s40104-018-0306-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yanhong Luo
- 1State Key Lab of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, 100193 China
| | - Xin Zhang
- 1State Key Lab of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, 100193 China
| | - Zhengpeng Zhu
- Technology Research and Development Department, New Hope Liuhe Co. Ltd, Beijing, 100102 China
| | - Ning Jiao
- 1State Key Lab of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, 100193 China
| | - Kai Qiu
- 1State Key Lab of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, 100193 China
| | - Jingdong Yin
- 1State Key Lab of Animal Nutrition, College of Animal Science & Technology, China Agricultural University, Beijing, 100193 China
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Ko SC, Ding Y, Kim J, Ye BR, Kim EA, Jung WK, Heo SJ, Lee SH. Bromophenol (5-bromo-3,4-dihydroxybenzaldehyde) isolated from red alga Polysiphonia morrowii inhibits adipogenesis by regulating expression of adipogenic transcription factors and AMP-activated protein kinase activation in 3T3-L1 adipocytes. Phytother Res 2018; 33:737-744. [PMID: 30570192 DOI: 10.1002/ptr.6266] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 11/06/2018] [Accepted: 11/29/2018] [Indexed: 11/07/2022]
Abstract
The aim of the present study was to investigate the effect of 5-bromo-3,4-dihydroxybenzaldehyde (BD) isolated from Polysiphonia morrowii on adipogenesis and differentiation of 3T3-L1 preadipocytes into mature adipocytes and its possible mechanism of action. Levels of lipid accumulation and triglyceride were significantly lower in BD treated cells than those in untreated cells. In addition, BD treatment reduced protein expression levels of peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding proteins α, and sterol regulatory element-binding protein 1 compared with control (no treatment). It also reduced expression levels of adiponectin, leptin, fatty acid synthase, and fatty acid binding protein 4. AMP-activated protein kinase activation was found to be one specific mechanism involved in the effect of BD. These results demonstrate that BD possesses inhibitory effect on adipogenesis through activating AMP-activated protein kinase signal pathway.
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Affiliation(s)
- Seok-Chun Ko
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, Republic of Korea
| | - Yuling Ding
- Department of Pharmaceutical Engineering, Soonchunhyang University, Asan, Republic of Korea
| | - Junseong Kim
- Jeju International Marine Science Center for Research and Education, Korea Institute of Ocean Science and Technology (KIOST), Jeju, Republic of Korea
| | - Bo-Ram Ye
- Jeju International Marine Science Center for Research and Education, Korea Institute of Ocean Science and Technology (KIOST), Jeju, Republic of Korea
| | - Eun-A Kim
- Jeju International Marine Science Center for Research and Education, Korea Institute of Ocean Science and Technology (KIOST), Jeju, Republic of Korea
| | - Won-Kyo Jung
- Marine-Integrated Bionics Research Center, Pukyong National University, Busan, Republic of Korea
- Department of Biomedical Engineering, and Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan, Republic of Korea
| | - Soo-Jin Heo
- Jeju International Marine Science Center for Research and Education, Korea Institute of Ocean Science and Technology (KIOST), Jeju, Republic of Korea
- Department of Marine Biology, University of Science and Technology, Daejeon, Republic of Korea
| | - Seung-Hong Lee
- Department of Pharmaceutical Engineering, Soonchunhyang University, Asan, Republic of Korea
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27
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Lee YK, Park JE, Lee M, Hardwick JP. Hepatic lipid homeostasis by peroxisome proliferator-activated receptor gamma 2. LIVER RESEARCH 2018; 2:209-215. [PMID: 31245168 PMCID: PMC6594548 DOI: 10.1016/j.livres.2018.12.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ or PPARG) is a ligand-activated transcription factor belonging to the nuclear hormone receptor superfamily. It plays a master role in the differentiation and proliferation of adipose tissues. It has two major isoforms, PPARγ1 and PPARγ2, encoded from a single gene using two separate promoters and alternative splicing. Among them, PPARγ2 is most abundantly expressed in adipocytes and plays major adipogenic and lipogenic roles in the tissue. Furthermore, it has been shown that PPARγ2 is also expressed in the liver, specifically in hepatocytes, and its expression level positively correlates with fat accumulation induced by pathological conditions such as obesity and diabetes. Knockout of the hepatic Pparg gene ameliorates hepatic steatosis induced by diet or genetic manipulations. Transcriptional activation of Pparg in the liver induces the adipogenic program to store fatty acids in lipid droplets as observed in adipocytes. Understanding how the hepatic Pparg gene expression is regulated will help develop preventative and therapeutic treatments for non-alcoholic fatty liver disease (NAFLD). Due to the potential adverse effect of hepatic Pparg gene deletion on peripheral tissue functions, therapeutic interventions that target PPARγ for fatty liver diseases require fine-tuning of this gene's expression and transcriptional activity.
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Affiliation(s)
- Yoon Kwang Lee
- Department of Integrative Medical Sciences, College of Medicine, Northeast Ohio Medical University, Rootstown, OH, USA,Corresponding author. Department of Integrative Medical Sciences, College of Medicine, Northeast Ohio Medical University, Rootstown, OH, USA., (Y.K. Lee)
| | - Jung Eun Park
- Department of Food Science and Human Nutrition, Chonbuk National University, Deokjin-gu, Jeonju, Republic of Korea
| | - Mikang Lee
- Department of Integrative Medical Sciences, College of Medicine, Northeast Ohio Medical University, Rootstown, OH, USA
| | - James P. Hardwick
- Department of Integrative Medical Sciences, College of Medicine, Northeast Ohio Medical University, Rootstown, OH, USA
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28
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Zhu T, Corraze G, Plagnes-Juan E, Skiba-Cassy S. Circulating miRNA measurements are reflective of cholesterol-based changes in rainbow trout (Oncorhynchus mykiss). PLoS One 2018; 13:e0206727. [PMID: 30395627 PMCID: PMC6218197 DOI: 10.1371/journal.pone.0206727] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/18/2018] [Indexed: 12/21/2022] Open
Abstract
MicroRNAs (miRNAs) are a class of small non-coding RNAs which are known to posttranscriptionally regulate the expression of most genes in both animals and plants. Meanwhile, studies have shown that numbers of miRNAs are present in body fluids including the plasma. Despite the mode of action of these circulating miRNAs still remains unknown, they have been found to be promising biomarkers for disease diagnosis, prognosis and response to treatment. In order to evaluate the potential of miRNAs as non-invasive biomarkers in aquaculture, a time-course experiment was implemented to investigate the postprandial regulation of miRNAs levels in liver and plasma as well as the hepatic expression of genes involved in cholesterol metabolism. We showed that miR-1, miR-33a, miR-122, miR-128 and miR-223 were expressed in the liver of rainbow trout and present at detectable level in the plasma. We also demonstrated that hepatic expression of miR-1, miR-122 and miR-128 were regulated by feed intake and reached their highest levels 12 hours after the meal. Interestingly, we observed that circulating levels of miR-128 and miR-223 are subjected to postprandial regulations similar to that observed in their hepatic counterparts. Statistical correlations were observed between liver and plasma for miR-128 and miR-223 and between hepatic and circulating miR-122, miR-128 and miR-223 and expression of genes related to cholesterol synthesis and efflux or glucose phosphorylation. These results demonstrated that circulating miR-122, miR-128 and miR-223 are potential biomarkers of cholesterol metabolism in rainbow trout.
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Affiliation(s)
- Tengfei Zhu
- INRA, Univ Pau & Pays Adour, E2S UPPA, UMR 1419, Nutrition Métabolisme Aquaculture, Saint Pée sur Nivelle, France
| | - Geneviève Corraze
- INRA, Univ Pau & Pays Adour, E2S UPPA, UMR 1419, Nutrition Métabolisme Aquaculture, Saint Pée sur Nivelle, France
| | - Elisabeth Plagnes-Juan
- INRA, Univ Pau & Pays Adour, E2S UPPA, UMR 1419, Nutrition Métabolisme Aquaculture, Saint Pée sur Nivelle, France
| | - Sandrine Skiba-Cassy
- INRA, Univ Pau & Pays Adour, E2S UPPA, UMR 1419, Nutrition Métabolisme Aquaculture, Saint Pée sur Nivelle, France
- * E-mail:
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Hahn O, Stubbs TM, Reik W, Grönke S, Beyer A, Partridge L. Hepatic gene body hypermethylation is a shared epigenetic signature of murine longevity. PLoS Genet 2018; 14:e1007766. [PMID: 30462643 PMCID: PMC6281273 DOI: 10.1371/journal.pgen.1007766] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 12/05/2018] [Accepted: 11/08/2018] [Indexed: 12/30/2022] Open
Abstract
Dietary, pharmacological and genetic interventions can extend health- and lifespan in diverse mammalian species. DNA methylation has been implicated in mediating the beneficial effects of these interventions; methylation patterns deteriorate during ageing, and this is prevented by lifespan-extending interventions. However, whether these interventions also actively shape the epigenome, and whether such epigenetic reprogramming contributes to improved health at old age, remains underexplored. We analysed published, whole-genome, BS-seq data sets from mouse liver to explore DNA methylation patterns in aged mice in response to three lifespan-extending interventions: dietary restriction (DR), reduced TOR signaling (rapamycin), and reduced growth (Ames dwarf mice). Dwarf mice show enhanced DNA hypermethylation in the body of key genes in lipid biosynthesis, cell proliferation and somatotropic signaling, which strongly correlates with the pattern of transcriptional repression. Remarkably, DR causes a similar hypermethylation in lipid biosynthesis genes, while rapamycin treatment increases methylation signatures in genes coding for growth factor and growth hormone receptors. Shared changes of DNA methylation were restricted to hypermethylated regions, and they were not merely a consequence of slowed ageing, thus suggesting an active mechanism driving their formation. By comparing the overlap in ageing-independent hypermethylated patterns between all three interventions, we identified four regions, which, independent of genetic background or gender, may serve as novel biomarkers for longevity-extending interventions. In summary, we identified gene body hypermethylation as a novel and partly conserved signature of lifespan-extending interventions in mouse, highlighting epigenetic reprogramming as a possible intervention to improve health at old age.
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Affiliation(s)
- Oliver Hahn
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Cellular Networks and Systems Biology, CECAD, University of Cologne, Cologne, Germany
| | - Thomas M. Stubbs
- Epigenetics Programme, The Babraham Institute, Cambridge, United Kingdom
| | - Wolf Reik
- Epigenetics Programme, The Babraham Institute, Cambridge, United Kingdom
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | | | - Andreas Beyer
- Cellular Networks and Systems Biology, CECAD, University of Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Linda Partridge
- Max Planck Institute for Biology of Ageing, Cologne, Germany
- Department of Genetics, Evolution and Environment, Institute of Healthy Ageing, University College London, London, United Kingdom
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Shimizu H, Hanzawa F, Kim D, Sun S, Laurent T, Umeki M, Ikeda S, Mochizuki S, Oda H. Delayed first active-phase meal, a breakfast-skipping model, led to increased body weight and shifted the circadian oscillation of the hepatic clock and lipid metabolism-related genes in rats fed a high-fat diet. PLoS One 2018; 13:e0206669. [PMID: 30379940 PMCID: PMC6209334 DOI: 10.1371/journal.pone.0206669] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 10/17/2018] [Indexed: 12/16/2022] Open
Abstract
The circadian clock is closely related to human health, such as metabolic syndrome and cardiovascular disease. Our previous study revealed that irregular feeding induced abnormal lipid metabolism with disruption of the hepatic circadian clock. We hypothesized that breakfast skipping induces lipid abnormalities, such as adiposity, by altering the hepatic circadian oscillation of clock and lipid metabolism-related genes. Here, we established a delayed first active-phase meal (DFAM) protocol as a breakfast-skipping model. Briefly, rats were fed a high-fat diet during zeitgeber time (ZT) 12-24 in a control group and ZT 16-4 in the DFAM group. The DFAM group showed increased body weight gain and perirenal adipose tissue weight without a change in total food intake. The circadian oscillations of hepatic clock and de novo fatty acid synthesis genes were delayed by 2-4 h because of DFAM. The peaks of serum insulin, a synchronizer for the liver clock, bile acids, and non-esterified fatty acid (NEFA) were delayed by 4-6 h because of DFAM. Moreover, DFAM delayed the surge in body temperature by 4 h and may have contributed to the increase in body weight gain and adipose tissue weight because of decreased energy expenditure. These data indicated a potential molecular mechanism by which breakfast skipping induces abnormal lipid metabolism, which is related to the altered circadian oscillation of hepatic gene expression. The results also suggested that the delayed peaks of serum NEFA, bile acids, and insulin entrain the circadian rhythm of hepatic clock and lipid metabolism-related genes.
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Affiliation(s)
- Hatsumi Shimizu
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
| | - Fumiaki Hanzawa
- Department of Nutritional Sciences, Nagoya University of Arts and Sciences, Nisshin, Japan
| | - Daeun Kim
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
| | - Shumin Sun
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
| | - Thomas Laurent
- Institute of Innovation for Future Society, Nagoya University, Nagoya, Japan
| | - Miki Umeki
- Faculty of Education, Oita University, Oita, Japan
| | - Saiko Ikeda
- Department of Nutritional Sciences, Nagoya University of Arts and Sciences, Nisshin, Japan
| | | | - Hiroaki Oda
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
- Institute of Innovation for Future Society, Nagoya University, Nagoya, Japan
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31
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Pesta M, Cedikova M, Dvorak P, Dvorakova J, Kulda V, Srbecka K, Muller L, Bouchalova V, Kralickova M, Babuska V, Kuncova J, Mullerova D. Trends in gene expression changes during adipogenesis in human adipose derived mesenchymal stem cells under dichlorodiphenyldichloroethylene exposure. Mol Cell Toxicol 2018. [DOI: 10.1007/s13273-018-0041-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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32
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Li D, Guo L, Deng B, Li M, Yang T, Yang F, Yang Z. Long non‑coding RNA HR1 participates in the expression of SREBP‑1c through phosphorylation of the PDK1/AKT/FoxO1 pathway. Mol Med Rep 2018; 18:2850-2856. [PMID: 30015961 PMCID: PMC6102743 DOI: 10.3892/mmr.2018.9278] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 06/20/2018] [Indexed: 11/20/2022] Open
Abstract
Sterol regulatory element binding protein‑1c (SREBP‑1c), which serves an essential role in the process of fat synthesis, is a key adjustment factor that regulates the dynamic balance of lipid metabolism. SREBP‑1c activates the transcription of multiple genes encoding for enzymes involved in the synthesis of triglycerides (TG) and fatty acids (FA) and accelerates lipid synthesis. Previous analysis indicated that long non‑coding RNA HCV regulated 1 (lncHR1) participates in lipid metabolism in vivo and regulates the level of SREBP‑1c protein. However, the mechanism of lncHR1 in regulating SREBP‑1c levels has not been revealed. In the present study, a fatty degeneration cell model was used to study how lncHR1 regulates the SREBP‑1c protein at the cellular level. Furthermore TG accumulation was assessed according to morphological analysis. Reverse transcription‑quantitative polymerase chain reaction and western blotting were used to detected the expression of SREBP‑1c. An activator and an inhibitor of phosphoinositide 3‑kinase/AKT phosphorylation (IGF‑1 and LY294002, respectively) were used to study the effect of lncHR1 on this pathway. It was verified that lncHR1 regulated SREBP‑1c levels and the phosphorylation of AKT in the steatosis cell model. Detailed molecular mechanisms mediated by lncHR1 were associated with the phosphorylation AKT/FoxO1 in Huh7 cell lines. Simultaneously, lncHR1 affected the location of FoxO1 inside and outside of the nucleus. Furthermore, the phosphorylation of PDK1 upstream of AKT was regulated through overexpression or knockdown lncHR1, as determined by western blotting. Taken together, these data show that lncHR1 inhibits SREBP‑1c levels through the phosphorylation of the PDK1/AKT/FoxO1 axis.
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Affiliation(s)
- Duan Li
- Department of Microbiology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
- Department of Psychiatry, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, Henan 453002, P.R. China
| | - Liwei Guo
- School of Forensic Medicine, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Baoguo Deng
- Department of Microbiology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Min Li
- Department of Microbiology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Tingting Yang
- Department of Microbiology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Fan Yang
- Department of Microbiology, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Zhijun Yang
- Department of Chemistry, School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
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Han LQ, Gao TY, Yang GY, Loor JJ. Overexpression of SREBF chaperone (SCAP) enhances nuclear SREBP1 translocation to upregulate fatty acid synthase (FASN) gene expression in bovine mammary epithelial cells. J Dairy Sci 2018; 101:6523-6531. [PMID: 29680640 DOI: 10.3168/jds.2018-14382] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 03/04/2018] [Indexed: 11/19/2022]
Abstract
Fatty acid synthase is a key enzyme for the synthesis of milk fat in the ruminant mammary gland. In nonruminants, sterol regulatory element binding protein 1 (SREBP1) is a regulator of FASN gene expression, and SREBF chaperone (SCAP) is essential for SREBP1 maturation and activity. However, the role of SCAP on the regulation of FASN gene expression in ruminants is unknown. The objective of this study was to investigate the transcriptional regulation of FASN by overexpressing SCAP in bovine mammary epithelial cells. A bovine SCAP expression vector, SREBP1 expression vector, and the promoter of FASN were cloned. The transcription factor binding sites of FASN promoter were predicted using bioinformatics analysis. After transfection with FASN promoter vectors in the immortalized bovine mammary epithelial cell line MAC-T, we co-overexpressed the SCAP + SREBP1 expression vector with pcDNA3.1 vector as control. The effect of SCAP + SREBP1 overexpression on the regulation of FASN was investigated using luciferase assay, immunofluorescence, Western blot, real-time PCR, and lipid droplet staining. We observed that co-overexpression of SCAP + SREBP1 significantly increased activity of the FASN promoter containing a sterol response element binding site. The FASN mRNA abundance and lipid droplet formation increased due to co-overexpression of SCAP + SREBP1. Compared with overexpression of SREBP1 alone, co-overexpression of SCAP + SREBP1 enhanced the nuclear translocation and nuclear SREBP1 protein abundance. Overall, as in nonruminants cells, results indicate that SCAP is essential for promoting nuclear translocation of SREBP1 and activation of FASN gene transcription, leading to lipid droplet formation in bovine mammary epithelial cells.
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Affiliation(s)
- L Q Han
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P.R. China; Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801
| | - T Y Gao
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P.R. China
| | - G Y Yang
- College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou 450002, P.R. China.
| | - J J Loor
- Department of Animal Sciences and Division of Nutritional Sciences, University of Illinois, Urbana 61801.
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Liu Y, Leslie PL, Jin A, Itahana K, Graves LM, Zhang Y. p32 regulates ER stress and lipid homeostasis by down-regulating GCS1 expression. FASEB J 2018; 32:3892-3902. [PMID: 29465311 DOI: 10.1096/fj.201701004rr] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sustained endoplasmic reticulum (ER) stress plays a major role in the development of many metabolic diseases, including cardiovascular disease, nonalcoholic fatty liver disease, insulin resistance, obesity, and diabetes. p32 is a multicompartmental protein involved in the regulation of oxidative phosphorylation and glucose oxidation. p32 ablation is associated with resistance to age-associated and diet-induced obesity through a mechanism that remains largely unknown. Here, we show that p32 promotes lipid biosynthesis by modulating fatty acid-induced ER stress. We found that p32 interacts with endoplasmic reticulum-anchored enzyme mannosyl-oligosaccharide glucosidase I (GCS1), an ER lumen-anchored glucosidase that is essential for the processing of N-linked glycoproteins, and reduces GCS1 in a lysosome-dependent manner. We demonstrate that increased GCS1 expression alleviates fatty acid-induced ER stress and is critical for suppressing ER stress-associated lipogenic gene activation, as demonstrated by the down-regulation of Srebp1, Fasn, and Acc. Consistently, suppression of p32 leads to increased GCS1 expression and alleviates fatty acid-induced ER stress, resulting in reduced lipid accumulation. Thus, p32 and GCS1 are regulators of ER function and lipid homeostasis and are potential therapeutic targets for the treatment of obesity and diabetes.-Liu, Y., Leslie, P. L., Jin, A., Itahana, K., Graves, L. M., Zhang, Y. p32 regulates ER stress and lipid homeostasis by down-regulating GCS1 expression.
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Affiliation(s)
- Yong Liu
- Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical College, Xuzhou, China
| | - Patrick L Leslie
- Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; and
| | - Aiwen Jin
- Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Koji Itahana
- Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lee M Graves
- Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Yanping Zhang
- Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.,Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical College, Xuzhou, China.,Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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35
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Wang LF, Wang XN, Huang CC, Hu L, Xiao YF, Guan XH, Qian YS, Deng KY, Xin HB. Inhibition of NAMPT aggravates high fat diet-induced hepatic steatosis in mice through regulating Sirt1/AMPKα/SREBP1 signaling pathway. Lipids Health Dis 2017; 16:82. [PMID: 28449683 PMCID: PMC5408374 DOI: 10.1186/s12944-017-0464-z] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 03/30/2017] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Nonalcoholic fatty liver disease is one of the most common liver diseases in the world and is a typical hepatic manifestation of metabolic syndrome which is characterized with lipid accumulation in liver. Nicotinamide phosphoribosyltransferase (NAMPT) has been recently identified as an enzyme involved in nicotinamide adenine dinucleotide (NAD+) biosynthesis and plays an important role in cellular metabolism in variety of organs in mammals. The aim of this study was to investigate the effects of NAMPT on high fat diet-induced hepatic steatosis. METHODS Hepatic steatosis model was induced by high fat diet (HFD) in C57BL/6 mice in vivo. HepG2 and Hep1-6 hepatocytes were transfected with NAMPT vector plasmid or treated with NAMPT inhibitor FK866 and then incubated with oleic acid. Lipids accumulation was examined by HE staining or oil red staining. Quantitative RT-PCR and Western blot were used to measure expressions of the genes involved in lipogenic synthesis. RESULTS FK866 significantly promoted liver steatosis in the mice fed with HFD and hepatic lipid accumulation in vitro, accompanied by the increases of the expressions of lipogenic genes such as sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FASN). Nicotinamide mononucleotide (NMN) and NAD+ significantly rescued the actions of FK866 in vitro. In contrast, overexpression of NAMPT in HepG2 and Hep1-6 hepatocytes ameliorated hepatic lipid accumulation. In addition, FK866 decreased the protein levels of Sirt1 and phospho-AMPKα in liver of the HFD fed mice. Furthermore, Resveratrol, a Sirt1 activator, significantly reduced lipogenic gene expressions, while EX-527, a Sirt1 specific inhibitor, had the opposite effects. CONCLUSION Our results demonstrated that inhibition of NAMPT aggravated the HFD- or oleic acid-induced hepatic steatosis through suppressing Sirt1-mediated signaling pathway. On the one hand, the inhibition of NAMPT reduced the production of NAD+ through inhibiting the NAD+ salvage pathway, resulting in the decrease of Sirt1 activity, and then attenuated the deacetylation of SREBP1 in which the inhibition of SREBP1 activity promoted the expressions of FASN and ACC. On the other hand, the reduced Sirt1 activity alleviated the activation of AMPKα to further enhance SREBP1 activities.
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Affiliation(s)
- Ling-Fang Wang
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
- School of Life Sciences, Nanchang University, Nanchang, 330031 China
| | - Xiao-Nv Wang
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Cong-Cong Huang
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Long Hu
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Yun-Fei Xiao
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
- School of Life Sciences, Nanchang University, Nanchang, 330031 China
| | - Xiao-Hui Guan
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Yi-Song Qian
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Ke-Yu Deng
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
| | - Hong-Bo Xin
- Institute of Translational Medicine, Nanchang University, 999 Xuefu Load, Honggutan District, Nanchang, 330031 China
- School of Life Sciences, Nanchang University, Nanchang, 330031 China
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36
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Ding Y, Wang Y, Jeon BT, Moon SH, Lee SH. Enzymatic hydrolysate from velvet antler suppresses adipogenesis in 3T3-L1 cells and attenuates obesity in high-fat diet-fed mice. EXCLI JOURNAL 2017; 16:328-339. [PMID: 28507477 PMCID: PMC5427470 DOI: 10.17179/excli2016-638] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 03/02/2017] [Indexed: 11/10/2022]
Abstract
The purpose of the current study was to investigate the potential anti-obesity activity of an enzymatic hydrolysate of velvet antler in inhibiting adipogenesis in 3T3-L1 cells and in high-fat diet (HFD)-fed obese mice. The enzymatic hydrolysate was prepared using the commercial food grade protease, Protamex. The velvet antler Protamex hydrolysate (VAPH) indicated profound inhibitory effects on adipogenesis dose-dependently by decreasing the accumulation of triglycerides and down-regulating expression levels of adipogenesis-related proteins C/EBPα, SREBP-1, and PPARγ. In a mouse model of HFD-induced obesity, oral administration of VAPH (100 and 300 mg/kg for 13 weeks) significantly reduced the body weight gain that had resulted from the HFD. VAPH treatment also lowered the serum glucose and triglyceride levels, while increasing the HDL-C level. Furthermore, the treatment greatly reduced hepatic lipid droplet accumulation as well as the size of adipocytes. Current findings demonstrate that VAPH has profound anti-obesity effects and could be an effective candidate for preventing obesity and obesity-related chronic diseases.
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Affiliation(s)
- Yuling Ding
- Department of Animal Bio and Applied Chemistry, Konkuk University, Chungju, 27478, Republic of Korea
| | - Yanmei Wang
- Jilin Sino-Rok Institue of Animal Science, Changchun, 130-600, China
| | - Byong-Tae Jeon
- Division of Food Bioscience and Korea Nokyong Research Center, Konkuk University, Chungju, 27478, Republic of Korea
| | - Sang-Ho Moon
- Division of Food Bioscience and Korea Nokyong Research Center, Konkuk University, Chungju, 27478, Republic of Korea
| | - Seung-Hong Lee
- Division of Food Bioscience and Korea Nokyong Research Center, Konkuk University, Chungju, 27478, Republic of Korea
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37
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Li D, Cheng M, Niu Y, Chi X, Liu X, Fan J, Fan H, Chang Y, Yang W. Identification of a novel human long non-coding RNA that regulates hepatic lipid metabolism by inhibiting SREBP-1c. Int J Biol Sci 2017; 13:349-357. [PMID: 28367099 PMCID: PMC5370442 DOI: 10.7150/ijbs.16635] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 01/14/2017] [Indexed: 12/27/2022] Open
Abstract
Sterol regulatory element binding proteins (SREBPs) are master regulators of hepatic lipid homeostasis. Aberrant expression of SREBPs frequently leads to lipid metabolism dysregulation. Long non-coding RNAs (lncRNAs) have been identified with diverse biological functions, but the effects of lncRNAs on lipid metabolism are rarely reported. Here, we identified a novel human specific lncRNA, lncHR1, as a negative regulator of SREBP-1c expression. Overexpression of lncHR1 inhibited expression of SREBP-1c and fatty acid synthase (FAS) and then repressed oleic acid-induced hepatic cell triglyceride (TG) and lipid droplet (LD) accumulation. In vivo, the data of established transgenic animals showed that mice with lncHR1 expression had less hepatic expression of SREBP-1c, FAS, Acetyl-CoA carboxylase α (ACCα), and less hepatic and plasma TG after being fed a high-fat diet. Therefore, we report a novel lncRNA which can decrease lipid metabolism by repressing SREBP-1c gene expression.
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Affiliation(s)
- Duan Li
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China;; Department of Microbiology, Xinxiang Medical University, Xinxiang, Henan 453003, P.R. China
| | - Min Cheng
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
| | - Yuqiang Niu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
| | - Xiaojing Chi
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
| | - Xiuying Liu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
| | - Jingjing Fan
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
| | - Heng Fan
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, P.R. China
| | - Yongsheng Chang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005, P.R. China
| | - Wei Yang
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100076, P.R. China
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38
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Randy A, Kim M, Nho CW. Ligularia fischeri and its constituent 3,4-dicaffeoylquinic acid improve obesity-induced nonalcoholic fatty liver disease by regulating lipid metabolism and activating AMPK. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.08.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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39
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Lin HP, Cheng ZL, He RY, Song L, Tian MX, Zhou LS, Groh BS, Liu WR, Ji MB, Ding C, Shi YH, Guan KL, Ye D, Xiong Y. Destabilization of Fatty Acid Synthase by Acetylation Inhibits De Novo Lipogenesis and Tumor Cell Growth. Cancer Res 2016; 76:6924-6936. [PMID: 27758890 DOI: 10.1158/0008-5472.can-16-1597] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/25/2016] [Accepted: 09/15/2016] [Indexed: 11/16/2022]
Abstract
Fatty acid synthase (FASN) is the terminal enzyme in de novo lipogenesis and plays a key role in cell proliferation. Pharmacologic inhibitors of FASN are being evaluated in clinical trials for treatment of cancer, obesity, and other diseases. Here, we report a previously unknown mechanism of FASN regulation involving its acetylation by KAT8 and its deacetylation by HDAC3. FASN acetylation promoted its degradation via the ubiquitin-proteasome pathway. FASN acetylation enhanced its association with the E3 ubiquitin ligase TRIM21. Acetylation destabilized FASN and resulted in decreased de novo lipogenesis and tumor cell growth. FASN acetylation was frequently reduced in human hepatocellular carcinoma samples, which correlated with increased HDAC3 expression and FASN protein levels. Our results suggest opportunities to target FASN acetylation as an anticancer strategy. Cancer Res; 76(23); 6924-36. ©2016 AACR.
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Affiliation(s)
- Huai-Peng Lin
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Zhou-Li Cheng
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Ruo-Yu He
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Lei Song
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, National Center for National Center for Protein Science (The PHOENIX Center), Beijing, China
| | - Meng-Xin Tian
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education, Shanghai, China
| | - Li-Sha Zhou
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China
| | - Beezly S Groh
- Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Wei-Ren Liu
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education, Shanghai, China
| | - Min-Biao Ji
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, China
| | - Chen Ding
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Proteomics, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, National Center for National Center for Protein Science (The PHOENIX Center), Beijing, China
| | - Ying-Hong Shi
- Department of Liver Surgery, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China.,Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education, Shanghai, China
| | - Kun-Liang Guan
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China. .,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Department of Pharmacology and Moores Cancer Center, University of California San Diego, La Jolla, California
| | - Dan Ye
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China. .,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Department of General Surgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Yue Xiong
- Molecular and Cell Biology Lab, Institute of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China. .,Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, and Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Genetic Engineering, Collaborative Innovation Center of Genetics and Development, School of Life Sciences, Fudan University, Shanghai, China.,Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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40
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Tricin, a methylated cereal flavone, suppresses fat accumulation by downregulating AKT and mTOR in 3T3-L1 preadipocytes. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.08.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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41
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Wang Y, Viscarra J, Kim SJ, Sul HS. Transcriptional regulation of hepatic lipogenesis. Nat Rev Mol Cell Biol 2016; 16:678-89. [PMID: 26490400 DOI: 10.1038/nrm4074] [Citation(s) in RCA: 453] [Impact Index Per Article: 56.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fatty acid and fat synthesis in the liver is a highly regulated metabolic pathway that is important for very low-density lipoprotein (VLDL) production and thus energy distribution to other tissues. Having common features at their promoter regions, lipogenic genes are coordinately regulated at the transcriptional level. Transcription factors, such as upstream stimulatory factors (USFs), sterol regulatory element-binding protein 1C (SREBP1C), liver X receptors (LXRs) and carbohydrate-responsive element-binding protein (ChREBP) have crucial roles in this process. Recently, insights have been gained into the signalling pathways that regulate these transcription factors. After feeding, high blood glucose and insulin levels activate lipogenic genes through several pathways, including the DNA-dependent protein kinase (DNA-PK), atypical protein kinase C (aPKC) and AKT-mTOR pathways. These pathways control the post-translational modifications of transcription factors and co-regulators, such as phosphorylation, acetylation or ubiquitylation, that affect their function, stability and/or localization. Dysregulation of lipogenesis can contribute to hepatosteatosis, which is associated with obesity and insulin resistance.
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Affiliation(s)
- Yuhui Wang
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Jose Viscarra
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Sun-Joong Kim
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
| | - Hei Sook Sul
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California 94720, USA
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42
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Zhang P, Li L, Bao Z, Huang F. Role of BAF60a/BAF60c in chromatin remodeling and hepatic lipid metabolism. Nutr Metab (Lond) 2016; 13:30. [PMID: 27127533 PMCID: PMC4848843 DOI: 10.1186/s12986-016-0090-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 04/19/2016] [Indexed: 02/07/2023] Open
Abstract
The switching defective/sucrose non-fermenting (SWI/SNF) complexes play an important role in hepatic lipid metabolism regulating both transcriptional activation and repression. BAF60a is a core subunit of the SWI/SNF chromatin-remodeling complexes that activates the transcription of fatty acid oxidation genes during fasting/glucagon. BAF60c, another subunit of SWI/SNF complexes, is recruited to form the lipoBAF complex that activates lipogenic genes, promoting lipogenesis and increasing the triglyceride level in response to feeding/insulin. Interestingly, hepatocytes located in the periportal and perivenous zones of the liver display a remarkable heterogeneity in the activity of various enzymes, metabolic functions and gene expression. Especially, fatty-acid oxidation was shown to be mostly periportal, whereas lipogenesis was mostly perivenous. Therefore, the present review highlights the role of of SWI/SNF regulating lipid metabolism under nutritional and hormonal control, which may be associated with hepatocyte heterogeneity.
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Affiliation(s)
- Ping Zhang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Lulu Li
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Zhengxi Bao
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Feiruo Huang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 China
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Palermo FA, Cocci P, Mozzicafreddo M, Arukwe A, Angeletti M, Aretusi G, Mosconi G. Tri- m-cresyl phosphate and PPAR/LXR interactions in seabream hepatocytes: revealed by computational modeling (docking) and transcriptional regulation of signaling pathways. Toxicol Res (Camb) 2016; 5:471-481. [PMID: 30090361 PMCID: PMC6061042 DOI: 10.1039/c5tx00314h] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 12/07/2015] [Indexed: 11/21/2022] Open
Abstract
The interactions between tri-m-cresyl phosphate (TMCP; an organophosphate flame retardant) and peroxisome proliferator activated receptors (PPARs) or liver X receptor α (LXRα) were investigated in seabream hepatocytes. The study was designed to characterize the binding of TMCP to PPARα, PPARγ and LXRα by computational modeling (docking) and transcriptional regulation of signaling pathways. TMCP mainly established a non-polar interaction with each receptor. These findings reflect the hydrophobic nature of this binding site, with fish LXRα showing the highest binding efficiency. Further, we have investigated the ability of TMCP to activate PPAR and LXR controlled transcriptional processes involved in lipid/cholesterol metabolism. TMCP induced the expression of all the target genes measured. All target genes were up-regulated at all exposure doses, except for fatty acid binding protein 7 (FABP7) and carnitine palmitoyltransferase 1B. Collectively, our data indicate that TMCP can affect fatty acid synthesis/uptake and cholesterol metabolism through LXRα and PPARs, together with interactions between these transcription factors in seabream liver.
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Affiliation(s)
- Francesco Alessandro Palermo
- School of Biosciences and Veterinary Medicine , University of Camerino , Via Gentile III Da Varano , I-62032 Camerino , MC , Italy . ; ; Tel: +39 0737 404920
| | - Paolo Cocci
- School of Biosciences and Veterinary Medicine , University of Camerino , Via Gentile III Da Varano , I-62032 Camerino , MC , Italy . ; ; Tel: +39 0737 404920
| | - Matteo Mozzicafreddo
- School of Biosciences and Veterinary Medicine , University of Camerino , Via Gentile III Da Varano , I-62032 Camerino , MC , Italy . ; ; Tel: +39 0737 404920
| | - Augustine Arukwe
- Department of Biology , Norwegian University of Science and Technology (NTNU) , Høgskoleringen 5 , 7491 Trondheim , Norway
| | - Mauro Angeletti
- School of Biosciences and Veterinary Medicine , University of Camerino , Via Gentile III Da Varano , I-62032 Camerino , MC , Italy . ; ; Tel: +39 0737 404920
| | - Graziano Aretusi
- Controllo Statistico , Pescara , Italy . http://www.controllostatistico.com
- Marine Protected Area Torre del Cerrano , 64025 Pineto , TE , Italy
| | - Gilberto Mosconi
- School of Biosciences and Veterinary Medicine , University of Camerino , Via Gentile III Da Varano , I-62032 Camerino , MC , Italy . ; ; Tel: +39 0737 404920
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Huo J, Ma Y, Liu JJ, Ho YS, Liu S, Soh LY, Chen S, Xu S, Han W, Hong A, Lim SC, Lam KP. Loss of Fas apoptosis inhibitory molecule leads to spontaneous obesity and hepatosteatosis. Cell Death Dis 2016; 7:e2091. [PMID: 26866272 PMCID: PMC4849152 DOI: 10.1038/cddis.2016.12] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/20/2015] [Accepted: 01/08/2016] [Indexed: 12/26/2022]
Abstract
Altered hepatic lipogenesis is associated with metabolic diseases such as obesity and hepatosteatosis. Insulin resistance and compensatory hyperinsulinaemia are key drivers of these metabolic imbalances. Fas apoptosis inhibitory molecule (FAIM), a ubiquitously expressed antiapoptotic protein, functions as a mediator of Akt signalling. Since Akt acts at a nodal point in insulin signalling, we hypothesize that FAIM may be involved in energy metabolism. In the current study, C57BL/6 wild-type (WT) and FAIM-knockout (FAIM-KO) male mice were fed with normal chow diet and body weight changes were monitored. Energy expenditure, substrate utilization and physical activities were analysed using a metabolic cage. Liver, pancreas and adipose tissue were subjected to histological examination. Serum glucose and insulin levels and lipid profiles were determined by biochemical assays. Changes in components of the insulin signalling pathway in FAIM-KO mice were examined by immunoblots. We found that FAIM-KO mice developed spontaneous non-hyperphagic obesity accompanied by hepatosteatosis, adipocyte hypertrophy, dyslipidaemia, hyperglycaemia and hyperinsulinaemia. In FAIM-KO liver, lipogenesis was elevated as indicated by increased fatty acid synthesis and SREBP-1 and SREBP-2 activation. Notably, protein expression of insulin receptor beta was markedly reduced in insulin target organs of FAIM-KO mice. Akt phosphorylation was also lower in FAIM-KO liver and adipose tissue as compared with WT controls. In addition, phosphorylation of insulin receptor substrate-1 and Akt2 in response to insulin treatment in isolated FAIM-KO hepatocytes was also markedly attenuated. Altogether, our data indicate that FAIM is a novel regulator of insulin signalling and plays an essential role in energy homoeostasis. These findings may shed light on the pathogenesis of obesity and hepatosteatosis.
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Affiliation(s)
- J Huo
- Immunology Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, #06-01 Centros, Singapore 138668, Singapore
| | - Y Ma
- Institute of Biomedicine, Ji Nan University, 601 HUANG PO DA DAO XI, Guang Zhou 510632, P.R. China
| | - J-J Liu
- Clinical Research Unit, Khoo Teck Puat Hospital, ALEXANDRA HEALTH PTE LTD, 90 Yishun Central, Singapore 768828, Singapore
| | - Y S Ho
- Metabolomics Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, #02-01 Centros, Singapore 138668, Singapore
| | - S Liu
- Clinical Research Unit, Khoo Teck Puat Hospital, ALEXANDRA HEALTH PTE LTD, 90 Yishun Central, Singapore 768828, Singapore
| | - L Y Soh
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Biomedical Sciences Institutes, 11 Biopolis Way, Helios, Singapore 138667, Singapore
| | - S Chen
- Metabolomics Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, #02-01 Centros, Singapore 138668, Singapore
| | - S Xu
- Immunology Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, #06-01 Centros, Singapore 138668, Singapore
| | - W Han
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, Biomedical Sciences Institutes, 11 Biopolis Way, Helios, Singapore 138667, Singapore
| | - A Hong
- Institute of Biomedicine, Ji Nan University, 601 HUANG PO DA DAO XI, Guang Zhou 510632, P.R. China
| | - S C Lim
- Diabetes Center, Khoo Teck Puat Hospital, ALEXANDRA HEALTH PTE LTD, 90 Yishun Central, Singapore 768828, Singapore
| | - K-P Lam
- Immunology Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, 20 Biopolis Way, #06-01 Centros, Singapore 138668, Singapore.,Department of Physiology, National University of Singapore, NUS Yong Loo Lin School of Medicine, Block MD9, 2 Medical Drive #04-01, Singapore 117597, Singapore.,Department of Microbiology, National University of Singapore, 5 Science Drive 2, Blk MD4, Level 3, Singapore 117545, Singapore.,School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551, Singapore
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Saravanan M, Pandikumar P, Ignacimuthu S. Effect of active sub-fraction of Ichnocarpus frutescens (L.) R.Br. in the management of obesity. JOURNAL OF ETHNOPHARMACOLOGY 2016; 177:117-125. [PMID: 26602455 DOI: 10.1016/j.jep.2015.11.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 11/05/2015] [Accepted: 11/16/2015] [Indexed: 06/05/2023]
Abstract
AIM OF THE STUDY Ichnocarpus frutescens (L.) R.Br. (Apocynaceae) is used by the traditional healers in India to treat diabetes and hyperlipidemia.This work aims to study the antiobesity effect of the active sub-fraction obtained from the leaves of this plant using in vitro and in vivo models. METHODOLOGY Active sub-fraction (Sfr3) isolated by column chromatography was analyzed using Gas chromatography and mass spectrometry. Adipogenesis and apoptosis were detected by oil red O and Hoechst-33342 staining, respectively, in 3T3-L1 adipocytes. Expression of specific marker genes involved in lipid metabolism was detected by Reverse Transcriptase Polymerase Chain Reaction in 3T3-L1 adipocytes and adipose tissues of C57 BL/6J mice, fed with high fat diet (HFD) and treated with Sfr3 and fenofibrate for 45 days. RESULTS The treatment with Sfr3 decreased lipid accumulation and caused apoptosis in adipocytes. In the HFD induced obese animals, serum and liver lipid levels were decreased and a significant decrease in body weight gain was observed dose dependently in 45 days treatment. Histopathological examination showed decrease in adipose mass and liver lipid accumulation. The effect of Sfr3 on the marker genes of adipocytes was significantly regulated at the treated doses both in vitro and in vivo. CONCLUSION Sfr3 of Ichnocarpus frutescens is effective in the management of obesity through adipocyte apoptosis.
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Affiliation(s)
- M Saravanan
- Division of Ethnopharmacology, Entomology Research Institute, Loyola College, Chennai, Tamil Nadu 600034, India
| | - P Pandikumar
- Division of Ethnopharmacology, Entomology Research Institute, Loyola College, Chennai, Tamil Nadu 600034, India
| | - S Ignacimuthu
- Division of Ethnopharmacology, Entomology Research Institute, Loyola College, Chennai, Tamil Nadu 600034, India; Visiting Professor Programme, Deanship of Scientific Research, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
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Sung J, Lee J. Capsicoside G, a furostanol saponin from pepper ( Capsicum annuum L.) seeds, suppresses adipogenesis through activation of AMP-activated protein kinase in 3T3-L1 cells. J Funct Foods 2016. [DOI: 10.1016/j.jff.2015.10.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Regulation of the fatty acid synthase promoter by liver X receptor α through direct and indirect mechanisms in goat mammary epithelial cells. Comp Biochem Physiol B Biochem Mol Biol 2015; 184:44-51. [DOI: 10.1016/j.cbpb.2015.02.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 02/20/2015] [Accepted: 02/23/2015] [Indexed: 11/20/2022]
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Oh GS, Lee GG, Yoon J, Oh WK, Kim SW. Selective inhibition of liver X receptor α-mediated lipogenesis in primary hepatocytes by licochalcone A. Chin Med 2015; 10:8. [PMID: 25937827 PMCID: PMC4416341 DOI: 10.1186/s13020-015-0037-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 04/13/2015] [Indexed: 11/24/2022] Open
Abstract
Background Sterol regulatory element binding protein-1c (SREBP-1c) is a regulator of the lipogenic pathway and is transcriptionally activated by liver X receptor α (LXRα). This study aims to investigate phytochemicals inhibiting the autonomous transactivity of LXRα with potentials as SREBP-1c inhibitors. Licochalcone A (LicA) is a flavonoid isolated from licorice root of Glycyrrhiza plant. Methods The effects of 238 natural chemicals on autonomous transactivity of LXRα were determined by the Gal4-TK-luciferase reporter system. The inclusion criteria for chemical selection was significant (P < 0.05) inhibition of autonomous transactivity of LXRα from three independent experiments. Transcript levels of mouse primary hepatocytes were measured by conventional or quantitative RT-PCR. Luciferase assay was used to assess synthetic or natural promoter activities of LXRα target genes. The effect of LicA on lipogenic activity was evaluated by measuring cellular triglycerides in mouse primary hepatocytes. The recruitment of RNA polymerase II to the LXR response element (LXRE) region was examined by chromatin immunoprecipitation. Results Among 238 natural compounds, LicA considerably inhibited the autonomous transactivity of LXRα and decreased the LXRα-dependent expression of SREBP-1c. LicA inhibited not only LXRα-dependent activation of the synthetic LXRE promoter but also that of the natural SREBP-1c promoter. As a consequence, LicA reduced the LXRα agonist-stimulated transcription of several lipogenic genes. Furthermore, LXRα-dependent hepatic lipid accumulation was repressed by LicA in mouse primary hepatocytes. Interestingly, the LXRα-dependent activation of ATP-binding cassette transporter A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1), other LXR target genes involved in reverse cholesterol transport (RCT), was not inhibited by LicA. LicA hindered the recruitment of RNA polymerase II to the LXRE of the SREBP-1c gene, but not of the ABCA1 gene. Conclusions LicA is a selective inhibitor of LXRα, repressing lipogenic LXRα target genes but not RCT-related LXRα target genes.
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Affiliation(s)
- Gyun-Sik Oh
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 Korea ; Bio-medical Institute of Technology, University of Ulsan College of Medicine, Seoul, 138-736 Korea
| | - Gang Gu Lee
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 Korea ; Bio-medical Institute of Technology, University of Ulsan College of Medicine, Seoul, 138-736 Korea
| | - Jin Yoon
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 Korea ; Bio-medical Institute of Technology, University of Ulsan College of Medicine, Seoul, 138-736 Korea
| | - Won Keun Oh
- Korea Bioactive Natural Material Bank, College of Pharmacy, Seoul National University, Seoul, 151-742 Korea
| | - Seung-Whan Kim
- Department of Pharmacology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, 138-736 Korea ; Bio-medical Institute of Technology, University of Ulsan College of Medicine, Seoul, 138-736 Korea
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Li J, Luo J, Xu H, Wang M, Zhu J, Shi H, Haile AB, Wang H, Sun Y. Fatty acid synthase promoter: Characterization, and transcriptional regulation by sterol regulatory element binding protein-1 in goat mammary epithelial cells. Gene 2015; 561:157-64. [DOI: 10.1016/j.gene.2015.02.034] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 01/22/2015] [Accepted: 02/12/2015] [Indexed: 12/18/2022]
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Kang H, Koppula S. Houttuynia cordata attenuates lipid accumulation via activation of AMP-activated protein kinase signaling pathway in HepG2 cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2014; 42:651-64. [PMID: 24871657 DOI: 10.1142/s0192415x14500426] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Houttuynia cordata (H. cordata) from the family Saururaceae is a perennial herb native to Southeast Asia. It possesses a range of medicinal properties to treat several disease symptoms including allergic inflammation and anaphylaxis. In the present investigation, we provided the molecular mechanisms underlying the role of H. cordata extract (HCE) in the prevention of high glucose-induced lipid accumulation in human HepG2 hepatocytes. HepG2 cells were pre-treated with various concentrations of HCE (0, 10, 20, 40, and 80 μg/mL) and treated with serum-free medium with normal glucose (5 mM) for 1 h, followed by exposure to high glucose (25 mM D-glucose) for 24 h. HCE significantly and dose-dependently attenuated lipid accumulation in human HepG2 hepatocytes when exposed to high glucose (25 mM D-glucose) (p < 0.05, p < 0.01 and p < 0.001 at 20, 40, and 80 μg/mL concentrations, respectively). Further, HCE attenuated the expression of fatty acid synthase (FAS), sterol regulatory element-binding protein-1 and glycerol 3-phosphate acyltransferases (GPATs). The adenosine monophosphate-activated protein kinase (AMPK) was also activated by HCE treatment when exposed to high glucose (25 mM D-glucose) in human HepG2 hepatocytes. This study suggests the hypolipidemic effects of HCE by the inhibition of lipid biosynthesis mediated through AMPK signaling, which may play an active role and can be developed as an anti-obesity agent.
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Affiliation(s)
- Hyun Kang
- Department of Medical Laboratory Science, College of Health Science, Dankook University, Cheonan, 330-714, Republic of Korea
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