101
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Lei L, Xiaoyi S, Fuchang L. Effect of dietary copper addition on lipid metabolism in rabbits. Food Nutr Res 2017; 61:1348866. [PMID: 28747869 PMCID: PMC5510220 DOI: 10.1080/16546628.2017.1348866] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Indexed: 12/16/2022] Open
Abstract
The present study was conducted to investigate the effect of copper supplementation on lipid metabolism in rabbits. Our study showed dietary copper addition (5-45 mg/kg) increased body mass gain, but decreased fat and liver weights compared with those in the control group (P < 0.05). Copper (45 mg/kg) addition significantly increased the skeletal muscle weight, but inhibited cytoplasmic lipid accumulation in liver, skeletal muscle and adipose tissue (P < 0.05). Compared with the control group, dietary copper addition (45 mg/kg) significantly increased plasma triglyceride levels but decreased very low density lipoprotein levels (P < 0.05). Copper treatment significantly increased gene expression of carnitine palmitoyltransferase (CPT) 1, CPT2 and peroxisome proliferator-activated receptor (PPAR) a in liver (P < 0.05). In skeletal muscle, CPT1, CPT2, fatty acid transport protein, fatty acid-binding protein, and PPARa mRNA as well as phosphorylated AMP-activated protein kinase (AMPK) levels were significantly up-regulated by copper treatment (P < 0.05). Rabbits receiving copper supplementation had higher CPT1, CPT2, PPARa and hormone-sensitive lipase mRNA levels in adipose tissue (P < 0.05). In conclusion, copper promoted skeletal muscle growth and reduced fat accretion. PPARa signaling in liver, skeletal muscle and adipose tissues and AMPK signaling in skeletal muscle tissue were involved in the regulation of lipid metabolism by copper.
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Affiliation(s)
- Liu Lei
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, China
| | - Sui Xiaoyi
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, China
| | - Li Fuchang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, China
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102
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Molecular mechanisms of appetite and obesity: a role for brain AMPK. Clin Sci (Lond) 2017; 130:1697-709. [PMID: 27555613 DOI: 10.1042/cs20160048] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 07/07/2016] [Indexed: 01/15/2023]
Abstract
Feeding behaviour and energy storage are both crucial aspects of survival. Thus, it is of fundamental importance to understand the molecular mechanisms regulating these basic processes. The AMP-activated protein kinase (AMPK) has been revealed as one of the key molecules modulating energy homoeostasis. Indeed, AMPK appears to be essential for translating nutritional and energy requirements into generation of an adequate neuronal response, particularly in two areas of the brain, the hypothalamus and the hindbrain. Failure of this physiological response can lead to energy imbalance, ultimately with extreme consequences, such as leanness or obesity. Here, we will review the data that put brain AMPK in the spotlight as a regulator of appetite.
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103
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Yang J, Nishihara R, Zhang X, Ogino S, Qian ZR. Energy sensing pathways: Bridging type 2 diabetes and colorectal cancer? J Diabetes Complications 2017; 31:1228-1236. [PMID: 28465145 PMCID: PMC5501176 DOI: 10.1016/j.jdiacomp.2017.04.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 04/04/2017] [Accepted: 04/10/2017] [Indexed: 12/14/2022]
Abstract
The recently rapid increase of obesity and type 2 diabetes mellitus has caused great burden to our society. A positive association between type 2 diabetes and risk of colorectal cancer has been reported by increasing epidemiological studies. The molecular mechanism of this connection remains elusive. However, type 2 diabetes may result in abnormal carbohydrate and lipid metabolism, high levels of circulating insulin, insulin growth factor-1, and adipocytokines, as well as chronic inflammation. All these factors could lead to the alteration of energy sensing pathways such as the AMP activated kinase (PRKA), mechanistic (mammalian) target of rapamycin (mTOR), SIRT1, and autophagy signaling pathways. The resulted impaired SIRT1 and autophagy signaling pathway could increase the risk of gene mutation and cancer genesis by decreasing genetic stability and DNA mismatch repair. The dysregulated mTOR and PRKA pathway could remodel cell metabolism during the growth and metastasis of cancer in order for the cancer cell to survive the unfavorable microenvironment such as hypoxia and low blood supply. Moreover, these pathways may be coupling metabolic and epigenetic alterations that are central to oncogenic transformation. Further researches including molecular pathologic epidemiologic studies are warranted to better address the precise links between these two important diseases.
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Affiliation(s)
- Juhong Yang
- Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, 450 Brookline Ave., Boston, MA 02215; 211 Collaborative Innovation Center of Tianjin for Medical Epigenetics, Key Laboratory of Hormone and Development (Ministry of Health), Metabolic Disease Hospital & Tianjin Institute of Endocrinology, Tianjin Medical University, Tianjin 300070, China.
| | - Reiko Nishihara
- Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, 450 Brookline Ave., Boston, MA 02215; Division of MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, 75 Francis Street, Boston, MA 02115; Department of Epidemiology, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115
| | - Xuehong Zhang
- Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, and Harvard Medical School, 75 Francis Street, Boston, MA 02115
| | - Shuji Ogino
- Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, 450 Brookline Ave., Boston, MA 02215; Division of MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, 75 Francis Street, Boston, MA 02115; Department of Epidemiology, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115
| | - Zhi Rong Qian
- Department of Oncologic Pathology, Dana-Farber Cancer Institute and Harvard Medical School, 450 Brookline Ave., Boston, MA 02215.
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104
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Heiss C, Spyridopoulos I, Haendeler J. Interventions to slow cardiovascular aging: Dietary restriction, drugs and novel molecules. Exp Gerontol 2017; 109:108-118. [PMID: 28658611 DOI: 10.1016/j.exger.2017.06.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 06/16/2017] [Accepted: 06/21/2017] [Indexed: 02/05/2023]
Abstract
Cardiovascular aging is a highly dynamic process. Despite the fact that cardiovascular function and structure change with age, they can still be modulated even in aged humans. The most prominent approaches to improve age-dependent vascular changes include dietary restriction and pharmacologic agents interacting with signaling pathways implicated in this context. These include inhibition of TOR, glycolysis, and GH/IGF-1, activation of sirtuins, and AMPK, as well as modulators of inflammation, epigenetic pathways, and telomeres. Promising nutritional approaches include Mediterranean diet and novel dietary bioactives including flavanols, anthocyanins, and lignins. Many plant bioactives improve cardiovascular parameters implied in vascular healthy aging including endothelial function, arterial stiffness, blood pressure, cholesterol, and glycemic control. However, the mechanism of action of most bioactives is not established and it remains to be elucidated whether they act as dietary restriction mimetics or via other modes of action. Even more importantly, whether these interventions can slow or even reverses components of cardiovascular aging itself and can increase healthspan or longevity in humans needs to be determined.
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Affiliation(s)
- Christian Heiss
- Division of Cardiology, Pulmonology and Vascular Medicine, Medical Faculty, University Duesseldorf, Moorenstr. 5, 40225 Duesseldorf, Germany.
| | - Ioakim Spyridopoulos
- Institute of Genetic Medicine, Medical Faculty, Newcastle University, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK.
| | - Judith Haendeler
- Central Institute of Clinical Chemistry and Laboratory Medicine, Medical Faculty, University of Duesseldorf, Moorenstr. 5, 40225 Duesseldorf, Germany; IUF-Leibniz Research Institute for Environmental Medicine, Auf'm Hennekamp 50, 40225 Duesseldorf, Germany.
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105
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Allen KM, Coughlan KA, Mahmood FN, Valentine RJ, Ruderman NB, Saha AK. The effects of troglitazone on AMPK in HepG2 cells. Arch Biochem Biophys 2017; 623-624:49-57. [DOI: 10.1016/j.abb.2017.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 03/27/2017] [Accepted: 05/15/2017] [Indexed: 11/24/2022]
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106
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Liu H, Zhong H, Yin Y, Jiang Z. Genistein has beneficial effects on hepatic steatosis in high fat-high sucrose diet-treated rats. Biomed Pharmacother 2017; 91:964-969. [PMID: 28514835 DOI: 10.1016/j.biopha.2017.04.130] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/25/2017] [Accepted: 04/30/2017] [Indexed: 02/07/2023] Open
Abstract
Genistein, a kind of phytoestrogen abundant in soybeans, is beneficial for alleviating non-alcoholic fatty liver disease (NAFLD), but the specific mechanism was not clearly understood. This study was designed to determine the effect of genistein on NAFLD and explore the possible mechanism. 36 male Sprague-Dawley rats were divided into 4 groups: the control group, high fat-high sucrose diet (HFS) group, HFS with 4mg/kg body weight genistein, and HFS with 8mg/kg body weight genistein. 12 weeks later, serum and hepatic lipid profiles, liver histopathological examination were characterized. The protein levels of liver AMP-activated protein kinase (AMPK), phosphorylation of AMPK (p-AMPK), acetyl-CoA carboxylase (ACC), phosphorylation of ACC (p-ACC) and sterol regulatory element binding protein 1 (SREBP-1) were determined by western blot. mRNA expressions of fatty acid synthase gene (FAS) and glycerol-3-phosphate acyltransferase (GPAT), peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyl transfer enzyme-1 (CPT-1) and acyl-CoA oxidase (ACO) were measured by reverse transcription polymerase chain reaction (RT-PCR). Results showed that genistein effectively improved serum and hepatic lipid metabolism and diminished fat accumulation in liver. And the protein level of hepatic p-AMPK and p-ACC were increased, but SREBP-1 was decreased by genistein. Meanwhile, the mRNA levels of FAS and GPAT were lower, but PPARα, CPT-1, ACO were higher in rats treated with genistein compared with HFS group. Collectively, genistein can improve hepatic steatosis via activating AMPK, thus promoting fatty acid oxidation and inhibiting lipid synthesis in liver.
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Affiliation(s)
- Huanhuan Liu
- Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou, China
| | - Huijia Zhong
- Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou, China
| | - Yimin Yin
- Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou, China
| | - Zhuoqin Jiang
- Department of Nutrition, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
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107
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McKay TB, Hjortdal J, Priyadarsini S, Karamichos D. Acute hypoxia influences collagen and matrix metalloproteinase expression by human keratoconus cells in vitro. PLoS One 2017; 12:e0176017. [PMID: 28426715 PMCID: PMC5398580 DOI: 10.1371/journal.pone.0176017] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/04/2017] [Indexed: 01/10/2023] Open
Abstract
Keratoconus (KC) is a progressive corneal ectasia linked to thinning of the central cornea. Hard contact lenses, rigid gas permeable lenses, and scleral lenses are the primary treatment modalities for early to mid- stages of KC to correct refractive error and astigmatism that develops as a result of an irregular corneal structure. These treatments are associated with significant drawbacks, including reduced availability of the tear film and oxygen to the corneal epithelium and stroma. However, it remains unknown whether hypoxia affects corneal integrity in the KC pathobiology. A number of studies have associated elevated oxidative stress with KC both in vitro and ex vivo. We hypothesized that KC-derived corneal fibroblasts are more susceptible to hypoxia-induced oxidative stress compared to healthy controls leading to exacerbation of corneal thinning in KC. This study investigated the effects of hypoxia on ECM secretion, assembly, and matrix metalloproteinase (MMP) expression in human corneal fibroblasts from healthy controls (HCFs) and KC patients (HKCs) in vitro. HCFs and HKCs were cultured in 3D constructs for 3 weeks and maintained or transferred to normoxic (21% O2) or hypoxic (2% O2) conditions, respectively, for 1 additional week. At the 4 week time-point, constructs were isolated and probed for Collagen I, III, and V, keratocan and MMP-1, -2, -3, -9, and -13, as well as hypoxia markers, hypoxia inducible factor-1α and lactoferrin. Conditioned media was also collected and probed for Collagen I, III, and V by Western blot. Thickness of the ECM assembled by HCFs and HKCs was measured using immunofluorescence microscopy. Results showed that hypoxia significantly reduced Collagen I secretion in HKCs, as well as upregulated the expression of MMP-1 and -2 with no significant effects on MMP-3, -9, or -13. ECM thickness was reduced in both cell types following 1 week in a low oxygen environment. Our study shows that hypoxia influences collagen and MMP expression by HKCs, which may have consequential effects on ECM structure in the context of KC.
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Affiliation(s)
- Tina B. McKay
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Jesper Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
| | - Shrestha Priyadarsini
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Dimitrios Karamichos
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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108
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Diaz A, Romero M, Vazquez T, Lechner S, Blomberg BB, Frasca D. Metformin improves in vivo and in vitro B cell function in individuals with obesity and Type-2 Diabetes. Vaccine 2017; 35:2694-2700. [PMID: 28392139 DOI: 10.1016/j.vaccine.2017.03.078] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/24/2017] [Accepted: 03/29/2017] [Indexed: 12/18/2022]
Abstract
Metformin (MET), the first-line medication for Type-2 Diabetes (T2D), has been shown to reduce chronic inflammation indirectly through reduction of hyperglycemia, or directly acting as anti-inflammatory drug. The effects of MET on B lymphocytes is uncharacterized. In the present study, we measured in vivo and in vitro influenza vaccine responses in 2 groups of T2D patients: recently diagnosed but not taking anti-diabetic drugs, and patients taking MET. Results show that B cell function and vaccine responses, hampered by obesity and T2D, are recovered by MET. Moreover, MET used in vitro to stimulate B cells from recently diagnosed T2D patients is also able to reduce B cell-intrinsic inflammation and increase antibody responses, similar to what we have seen in B cells from patients taking MET, who show increased responses to the influenza vaccine in vivo. These results are the first to show an effect of MET on B cells.
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Affiliation(s)
- Alain Diaz
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Maria Romero
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Thomas Vazquez
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Suzanne Lechner
- Department of Psychiatry, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Bonnie B Blomberg
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Daniela Frasca
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA.
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109
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Julien SG, Kim SY, Brunmeir R, Sinnakannu JR, Ge X, Li H, Ma W, Yaligar J, KN BP, Velan SS, Röder PV, Zhang Q, Sim CK, Wu J, Garcia-Miralles M, Pouladi MA, Xie W, McFarlane C, Han W, Xu F. Narciclasine attenuates diet-induced obesity by promoting oxidative metabolism in skeletal muscle. PLoS Biol 2017; 15:e1002597. [PMID: 28207742 PMCID: PMC5331945 DOI: 10.1371/journal.pbio.1002597] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/23/2017] [Indexed: 12/19/2022] Open
Abstract
Obesity develops when caloric intake exceeds metabolic needs. Promoting energy expenditure represents an attractive approach in the prevention of this fast-spreading epidemic. Here, we report a novel pharmacological strategy in which a natural compound, narciclasine (ncls), attenuates diet-induced obesity (DIO) in mice by promoting energy expenditure. Moreover, ncls promotes fat clearance from peripheral metabolic tissues, improves blood metabolic parameters in DIO mice, and protects these mice from the loss of voluntary physical activity. Further investigation suggested that ncls achieves these beneficial effects by promoting a shift from glycolytic to oxidative muscle fibers in the DIO mice thereby enhancing mitochondrial respiration and fatty acid oxidation (FAO) in the skeletal muscle. Moreover, ncls strongly activates AMPK signaling specifically in the skeletal muscle. The beneficial effects of ncls treatment in fat clearance and AMPK activation were faithfully reproduced in vitro in cultured murine and human primary myotubes. Mechanistically, ncls increases cellular cAMP concentration and ADP/ATP ratio, which further lead to the activation of AMPK signaling. Blocking AMPK signaling through a specific inhibitor significantly reduces FAO in myotubes. Finally, ncls also enhances mitochondrial membrane potential and reduces the formation of reactive oxygen species in cultured myotubes. Narciclasine is a natural compound that attenuates diet-induced obesity in mice by promoting energy expenditure; it also induces a number of beneficial metabolic effects and activates AMPK signaling in skeletal muscle. Obesity results from the imbalance of food intake and energy expenditure. Since the restriction of food intake is difficult and inefficient in maintaining long-term weight loss, enhancing energy expenditure is now an attractive approach in combating obesity. Here, we analysed the role in this process of a natural compound called narciclasine. We showed that narciclasine treatment reduces excess fat accumulation in peripheral metabolic tissues, improves blood metabolic parameters and insulin sensitivity in obese mice, and protects these mice from the loss of voluntary physical activity. Further investigation suggested that narciclasine enhances mitochondrial respiration and fatty acid consumption in the skeletal muscle. In addition, narciclasine strongly activates the AMP-activated protein kinase (AMPK) signaling, which is a central sensor of the cellular energy status and a key player in maintaining energy homeostasis, specifically in the skeletal muscle. Mechanistically, we found that narciclasine increases cAMP concentration and ADP/ATP ratio in muscle cells, which further lead to AMPK activation. Finally, we observed that narciclasine increases mitochondrial membrane potential and reduces the production of reactive oxygen species in muscle cells. Our findings suggest that narciclasine is a natural compound that attenuates diet-induced obesity in mice by promoting energy expenditure.
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MESH Headings
- AMP-Activated Protein Kinases/metabolism
- Adenosine Diphosphate/metabolism
- Adenosine Triphosphate/metabolism
- Amaryllidaceae Alkaloids/pharmacology
- Amaryllidaceae Alkaloids/therapeutic use
- Animals
- Biomarkers/metabolism
- Cell Respiration/drug effects
- Cells, Cultured
- Cyclic AMP/metabolism
- Diet/adverse effects
- Diet, High-Fat
- Energy Metabolism/drug effects
- Enzyme Activation/drug effects
- Fatty Acids/metabolism
- Humans
- Male
- Membrane Potential, Mitochondrial/drug effects
- Mice
- Mice, Inbred C57BL
- Mitochondria/drug effects
- Mitochondria/metabolism
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/metabolism
- Muscle Fibers, Slow-Twitch/drug effects
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Obesity/drug therapy
- Obesity/metabolism
- Oxidation-Reduction/drug effects
- Phenanthridines/pharmacology
- Phenanthridines/therapeutic use
- Physical Conditioning, Animal
- Protective Agents/pharmacology
- Protective Agents/therapeutic use
- Reactive Oxygen Species/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
- Sofi G. Julien
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Sun-Yee Kim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Reinhard Brunmeir
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Joanna R. Sinnakannu
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Xiaojia Ge
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Hongyu Li
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Wei Ma
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Jadegoud Yaligar
- Magnetic Resonance Spectroscopy and Metabolic Imaging Group, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Bhanu Prakash KN
- Magnetic Resonance Spectroscopy and Metabolic Imaging Group, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Sendhil S. Velan
- Magnetic Resonance Spectroscopy and Metabolic Imaging Group, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
| | - Pia V. Röder
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Republic of Singapore
| | - Qiongyi Zhang
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Choon Kiat Sim
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Jingyi Wu
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, THU-PKU Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Marta Garcia-Miralles
- Translational Laboratory in Genetic Medicine, A*STAR, Singapore, Republic of Singapore
| | - Mahmoud A. Pouladi
- Translational Laboratory in Genetic Medicine, A*STAR, Singapore, Republic of Singapore
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore
| | - Wei Xie
- Center for Stem Cell Biology and Regenerative Medicine, MOE Key Laboratory of Bioinformatics, THU-PKU Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Craig McFarlane
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
| | - Weiping Han
- Laboratory of Metabolic Medicine, Singapore Bioimaging Consortium, A*STAR, Singapore, Republic of Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Republic of Singapore
| | - Feng Xu
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Republic of Singapore
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Republic of Singapore
- * E-mail:
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110
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Choung JS, Lee YS, Jun HS. Exendin-4 increases oxygen consumption and thermogenic gene expression in muscle cells. J Mol Endocrinol 2017; 58:79-90. [PMID: 27872157 DOI: 10.1530/jme-16-0078] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 11/21/2016] [Indexed: 02/02/2023]
Abstract
Glucagon-like peptide-1 (GLP1) has many anti-diabetic actions and also increases energy expenditure in vivo As skeletal muscle is a major organ controlling energy metabolism, we investigated whether GLP1 can affect energy metabolism in muscle. We found that treatment of differentiated C2C12 cells with exendin-4 (Ex-4), a GLP1 receptor agonist, reduced oleate:palmitate-induced lipid accumulation and triglyceride content compared with cells without Ex-4 treatment. When we examined the oxygen consumption rate (OCR), not only the basal OCR but also the OCR induced by oleate:palmitate addition was significantly increased in Ex-4-treated differentiated C2C12 cells, and this was inhibited by exendin-9, a GLP1 receptor antagonist. The expression of uncoupling protein 1 (UCP1), β3-adrenergic receptor, peroxisome proliferator-activator receptor a (PPARa) and farnesoid X receptor mRNA was significantly upregulated in Ex-4-treated differentiated C2C12 cells, and the upregulation of these mRNA was abolished by treatment with adenylate cyclase inhibitor (2'5'-dideoxyadenosine) or PKA inhibitor (H-89). As well, intramuscular injection of Ex-4 into diet-induced obese mice significantly increased the expression of UCP1, PPARa and p-AMPK in muscle. We suggest that exposure to GLP1 increases energy expenditure in muscle through the upregulation of fat oxidation and thermogenic gene expression, which may contribute to reducing obesity and insulin resistance.
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Affiliation(s)
- Jin-Seung Choung
- College of Pharmacy and Gachon Institute of Pharmaceutical ScienceGachon University, Incheon, Republic of Korea
- Lee Gil Ya Cancer and Diabetes InstituteGachon University, Incheon, Republic of Korea
| | - Young-Sun Lee
- Lee Gil Ya Cancer and Diabetes InstituteGachon University, Incheon, Republic of Korea
| | - Hee-Sook Jun
- College of Pharmacy and Gachon Institute of Pharmaceutical ScienceGachon University, Incheon, Republic of Korea
- Lee Gil Ya Cancer and Diabetes InstituteGachon University, Incheon, Republic of Korea
- Gachon Medical Research InstituteGil Hospital, Incheon, Republic of Korea
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111
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Li J, Li X, Li Z, Zhang L, Liu Y, Ding H, Yin S. Isofraxidin, a coumarin component improves high-fat diet induced hepatic lipid homeostasis disorder and macrophage inflammation in mice. Food Funct 2017; 8:2886-2896. [DOI: 10.1039/c7fo00290d] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Isofraxidin (IF) is a coumarin compound produced in the functional foodsSiberian ginsengandApium graveolens.
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Affiliation(s)
- Jian Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Xiaofei Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Zhike Li
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Lu Zhang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Yonggang Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Hong Ding
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery
- Ministry of Education
- Wuhan University School of Pharmaceutical Sciences
- Wuhan University
- Wuhan
| | - Shanye Yin
- Department of Cell Biology
- Harvard Medical School
- Boston
- USA
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112
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Frasca D, Diaz A, Romero M, Blomberg BB. Human peripheral late/exhausted memory B cells express a senescent-associated secretory phenotype and preferentially utilize metabolic signaling pathways. Exp Gerontol 2017; 87:113-120. [DOI: 10.1016/j.exger.2016.12.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 11/07/2016] [Accepted: 12/02/2016] [Indexed: 12/22/2022]
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113
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Kelly M, Ruderman NB, Tomas E. AMP-activated protein kinase and its regulation by adiponectin and interleukin-6. SCANDINAVIAN JOURNAL OF FOOD & NUTRITION 2016. [DOI: 10.1080/17482970601076305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Meghan Kelly
- Diabetes Unit, Section of EndocrinologyBoston University School of MedicineBostonMassachusettsUSA
| | - Neil B. Ruderman
- Diabetes Unit, Section of EndocrinologyBoston University School of MedicineBostonMassachusettsUSA
| | - Eva Tomas
- Diabetes Unit, Section of EndocrinologyBoston University School of MedicineBostonMassachusettsUSA
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114
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Glucagon-like peptide-1 effects lipotoxic oxidative stress by regulating the expression of microRNAs. Biochem Biophys Res Commun 2016; 482:1462-1468. [PMID: 27956176 DOI: 10.1016/j.bbrc.2016.12.058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 12/08/2016] [Indexed: 12/24/2022]
Abstract
Aim to confirm whether the treatment of GLP-1 can modulated body weight, lipid metabolism, insulin content, pancreas oxidative stress, improved T-AOC, MDA levels related to FFA-Induced oxidative stress in C57BL/6 mice and INS-1 cells. In this study, GLP-1 makes the expression of AMPK, PPARα, CPT1A and SIRT1 increased, and the expression of SREBP1c, miR-33 and miR-370 decreased. Interestingly, the effects of GLP-1 were less dose dependent as GLP-1 regulated the FFA, which related to gene expression at much lower doses (3 μg/kg, 10 mM, mice and INS-1 respectively) and effects were relatively maintained at higher dose (30 μg/kg, 100 mM, mice and INS-1 respectively) as well. Subsequently, the analysis showed that inhibited expression of miR-33 and miR-370 upregulated the expression of CPT1A and SIRT1, reversely mimics. These results demonstrated for the first time that GLP-1 improve lipotoxic oxidative stress of pancreas by regulate expression of microRNAs.
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115
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Rehman K, Akash MSH. Mechanisms of inflammatory responses and development of insulin resistance: how are they interlinked? J Biomed Sci 2016; 23:87. [PMID: 27912756 PMCID: PMC5135788 DOI: 10.1186/s12929-016-0303-y] [Citation(s) in RCA: 298] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 11/24/2016] [Indexed: 02/06/2023] Open
Abstract
Background Insulin resistance (IR) is one of the major hallmark for pathogenesis and etiology of type 2 diabetes mellitus (T2DM). IR is directly interlinked with various inflammatory responses which play crucial role in the development of IR. Inflammatory responses play a crucial role in the pathogenesis and development of IR which is one of the main causative factor for the etiology of T2DM. Methods A comprehensive online English literature was searched using various electronic search databases. Different search terms for pathogenesis of IR, role of various inflammatory responses were used and an advanced search was conducted by combining all the search fields in abstracts, keywords, and titles. Results We summarized the data from the searched articles and found that inflammatory responses activate the production of various pro-inflammatory mediators notably cytokines, chemokines and adipocytokines through the involvement of various transcriptional mediated molecular pathways, oxidative and metabolic stress. Overnutrition is one of the major causative factor that contributes to induce the state of low-grade inflammation due to which accumulation of elevated levels of glucose and/or lipids in blood stream occur that leads to the activation of various transcriptional mediated molecular and metabolic pathways. This results in the induction of various pro-inflammatory mediators that are decisively involved to provoke the pathogenesis of tissue-specific IR by interfering with insulin signaling pathways. Once IR is developed, it increases oxidative stress in β-cells of pancreatic islets and peripheral tissues which impairs insulin secretion, and insulin sensitivity in β-cells of pancreatic islets and peripheral tissues, respectively. Moreover, we also summarized the data regarding various treatment strategies of inflammatory responses-induced IR. Conclusions In this article, we have briefly described that how pro-inflammatory mediators, oxidative stress, transcriptional mediated molecular and metabolic pathways are involved in the pathogenesis of tissues-specific IR. Moreover, based on recent investigations, we have also described that to counterfeit these inflammatory responses is one of the best treatment strategy to prevent the pathogenesis of IR through ameliorating the incidences of inflammatory responses.
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Affiliation(s)
- Kanwal Rehman
- Institute of Pharmacy, Physiology and Pharmacology, University of Agriculture, Faisalabad, Pakistan
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116
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The Effect of Urtica dioica Hydro-Alcoholic Extract on Glycemic Index and AMP-Activated Protein Kinase Levels in Diabetic Patients: A Randomized Single-Blind Clinical Trial. IRANIAN RED CRESCENT MEDICAL JOURNAL 2016. [DOI: 10.5812/ircmj.40572] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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117
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Ham H, Woo KS, Lee YY, Lee B, Kim IH, Lee J. Unsaponifiable Matter from Rice Bran Attenuates High Glucose-Induced Lipid Accumulation by Activating AMPK in HepG2 Cells. J Food Biochem 2016. [DOI: 10.1111/jfbc.12313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hyeonmi Ham
- Department of Central Area; National Institute of Crop Science, Rural Development Administration; Suwon Gyeonggi 16613 Republic of Korea
| | - Koan Sik Woo
- Department of Central Area; National Institute of Crop Science, Rural Development Administration; Suwon Gyeonggi 16613 Republic of Korea
| | - Yu Young Lee
- Department of Central Area; National Institute of Crop Science, Rural Development Administration; Suwon Gyeonggi 16613 Republic of Korea
| | - Byongwon Lee
- Department of Central Area; National Institute of Crop Science, Rural Development Administration; Suwon Gyeonggi 16613 Republic of Korea
| | - In-Hwan Kim
- Department of Food and Nutrition; Korea University; Seoul 02841 Republic of Korea
| | - Junsoo Lee
- Division of Food and Animal Sciences; Chungbuk National University; Cheongju Chungbuk 28644 Republic of Korea
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118
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Liu GY, Liu J, Wang YL, Liu Y, Shao Y, Han Y, Qin YR, Xiao FJ, Li PF, Zhao LJ, Gu EY, Chen SY, Gao LH, Wu CT, Hu XW, Duan HF. Adipose-Derived Mesenchymal Stem Cells Ameliorate Lipid Metabolic Disturbance in Mice. Stem Cells Transl Med 2016; 5:1162-70. [PMID: 27381991 DOI: 10.5966/sctm.2015-0239] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 02/23/2016] [Indexed: 12/25/2022] Open
Abstract
UNLABELLED : Adipose-derived mesenchymal stem cells (AD-MSCs) have been shown to ameliorate hyperglycemia in diabetic animals and individuals. However, little is known about whether AD-MSCs affect lipid metabolism. Here we have demonstrated for the first time that AD-MSC infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in db/db obese mice and diet-induced obesity mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia and associated cardiovascular diseases. SIGNIFICANCE Mesenchymal stem cells (MSCs) are considered one of the most promising types of stem cells for translational application because of their rich tissue sources, multilineage differentiation capacity, and easy amplification in vitro and unique immunobiological properties. This study demonstrated that adipose-derived MSCs (AD-MSCs) infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in obese mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue were demonstrated to contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia.
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Affiliation(s)
- Guang-Yang Liu
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Jin Liu
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - You-Liang Wang
- Beijing Institute of Biotechnology, Beijing, People's Republic of China
| | - Yang Liu
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Yong Shao
- Beijing Institute of Biotechnology, Beijing, People's Republic of China
| | - Yan Han
- Department of Plastic Surgery, Chinese PLA General Hospital, Beijing, People's Republic of China
| | - Ya-Ru Qin
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Feng-Jun Xiao
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Peng-Fei Li
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Lan-Jun Zhao
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - En-Yan Gu
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Si-Yu Chen
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Li-Hua Gao
- Beijing Institute of Biotechnology, Beijing, People's Republic of China
| | - Chu-Tse Wu
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
| | - Xian-Wen Hu
- Beijing Institute of Biotechnology, Beijing, People's Republic of China
| | - Hai-Feng Duan
- Beijing Institute of Radiation Medicine, Beijing, People's Republic of China
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119
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He L, Hamm JA, Reddy A, Sams D, Peliciari-Garcia RA, McGinnis GR, Bailey SM, Chow CW, Rowe GC, Chatham JC, Young ME. Biotinylation: a novel posttranslational modification linking cell autonomous circadian clocks with metabolism. Am J Physiol Heart Circ Physiol 2016; 310:H1520-32. [PMID: 27084392 PMCID: PMC4935513 DOI: 10.1152/ajpheart.00959.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 04/08/2016] [Indexed: 01/07/2023]
Abstract
Circadian clocks are critical modulators of metabolism. However, mechanistic links between cell autonomous clocks and metabolic processes remain largely unknown. Here, we report that expression of the biotin transporter slc5a6 gene is decreased in hearts of two distinct genetic mouse models of cardiomyocyte-specific circadian clock disruption [i.e., cardiomyocyte-specific CLOCK mutant (CCM) and cardiomyocyte-specific BMAL1 knockout (CBK) mice]. Biotinylation is an obligate posttranslational modification for five mammalian carboxylases: acetyl-CoA carboxylase α (ACCα), ACCβ, pyruvate carboxylase (PC), methylcrotonyl-CoA carboxylase (MCC), and propionyl-CoA carboxylase (PCC). We therefore hypothesized that the cardiomyocyte circadian clock impacts metabolism through biotinylation. Consistent with decreased slc5a6 expression, biotinylation of all carboxylases is significantly decreased (10-46%) in CCM and CBK hearts. In association with decreased biotinylated ACC, oleate oxidation rates are increased in both CCM and CBK hearts. Consistent with decreased biotinylated MCC, leucine oxidation rates are significantly decreased in both CCM and CBK hearts, whereas rates of protein synthesis are increased. Importantly, feeding CBK mice with a biotin-enriched diet for 6 wk normalized myocardial 1) ACC biotinylation and oleate oxidation rates; 2) PCC/MCC biotinylation (and partially restored leucine oxidation rates); and 3) net protein synthesis rates. Furthermore, data suggest that the RRAGD/mTOR/4E-BP1 signaling axis is chronically activated in CBK and CCM hearts. Finally we report that the hepatocyte circadian clock also regulates both slc5a6 expression and protein biotinylation in the liver. Collectively, these findings suggest that biotinylation is a novel mechanism by which cell autonomous circadian clocks influence metabolic pathways.
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Affiliation(s)
- Lan He
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - J Austin Hamm
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama
| | - Alex Reddy
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - David Sams
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Graham R McGinnis
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Shannon M Bailey
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Chi-Wing Chow
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York
| | - Glenn C Rowe
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - John C Chatham
- Division of Molecular and Cellular Pathology, Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Martin E Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama;
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120
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Sun J, Tang Y, Yu X, Xu Y, Liu P, Xiao L, Liu L, Deng Q, Yao P. Flaxseed lignans alleviate high fat diet-induced hepatic steatosis and insulin resistance in mice: Potential involvement of AMP-activated protein kinase. J Funct Foods 2016. [DOI: 10.1016/j.jff.2016.04.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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121
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Pepin É, Al-Mass A, Attané C, Zhang K, Lamontagne J, Lussier R, Madiraju SRM, Joly E, Ruderman NB, Sladek R, Prentki M, Peyot ML. Pancreatic β-Cell Dysfunction in Diet-Induced Obese Mice: Roles of AMP-Kinase, Protein Kinase Cε, Mitochondrial and Cholesterol Metabolism, and Alterations in Gene Expression. PLoS One 2016; 11:e0153017. [PMID: 27043434 PMCID: PMC4820227 DOI: 10.1371/journal.pone.0153017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/22/2016] [Indexed: 12/27/2022] Open
Abstract
Diet induced obese (DIO) mice can be stratified according to their weight gain in response to high fat diet as low responders (LDR) and high responders (HDR). This allows the study of β-cell failure and the transitions to prediabetes (LDR) and early diabetes (HDR). C57BL/6N mice were fed for 8 weeks with a normal chow diet (ND) or a high fat diet and stratified as LDR and HDR. Freshly isolated islets from ND, LDR and HDR mice were studied ex-vivo for mitochondrial metabolism, AMPK activity and signalling, the expression and activity of key enzymes of energy metabolism, cholesterol synthesis, and mRNA profiling. Severely compromised glucose-induced insulin secretion in HDR islets, as compared to ND and LDR islets, was associated with suppressed AMP-kinase activity. HDR islets also showed reduced acetyl-CoA carboxylase activity and enhanced activity of 3-hydroxy-3-methylglutaryl-CoA reductase, which led respectively to elevated fatty acid oxidation and increased cholesterol biosynthesis. HDR islets also displayed mitochondrial membrane hyperpolarization and reduced ATP turnover in the presence of elevated glucose. Expression of protein kinase Cε, which reduces both lipolysis and production of signals for insulin secretion, was elevated in DIO islets. Genes whose expression increased or decreased by more than 1.2-fold were minor between LDR and ND islets (17 differentially expressed), but were prominent between HDR and ND islets (1508 differentially expressed). In HDR islets, particularly affected genes were related to cell cycle and proliferation, AMPK signaling, mitochondrial metabolism and cholesterol metabolism. In conclusion, chronically reduced AMPK activity, mitochondrial dysfunction, elevated cholesterol biosynthesis in islets, and substantial alterations in gene expression accompany β-cell failure in HDR islets. The β-cell compensation process in the prediabetic state (LDR) is largely independent of transcriptional adaptive changes, whereas the transition to early diabetes (HDR) is associated with major alterations in gene expression.
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Affiliation(s)
- Émilie Pepin
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - Anfal Al-Mass
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
- Departments of Medicine and Human Genetics, McGill University, Montreal, Québec, Canada
| | - Camille Attané
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - Kezhuo Zhang
- Departments of Medicine and Human Genetics, McGill University, Montreal, Québec, Canada
| | - Julien Lamontagne
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - Roxane Lussier
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - S. R. Murthy Madiraju
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - Erik Joly
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
| | - Neil B. Ruderman
- Departments of Medicine and Physiology and Biophysics, Boston University School of Medicine and Diabetes Unit, Boston Medical Center, Boston, MA, United States of America
| | - Robert Sladek
- Departments of Medicine and Human Genetics, McGill University, Montreal, Québec, Canada
| | - Marc Prentki
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
- Departments of Nutrition, Biochemistry and Molecular Medicine, Faculty of Medicine, University of Montréal, Montreal, Québec, Canada
- * E-mail: (MP); (MLP)
| | - Marie-Line Peyot
- Montreal Diabetes Research Center and Centre de Recherche du CHUM, Montréal, Québec, Canada
- * E-mail: (MP); (MLP)
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122
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Prastowo S, Amin A, Rings F, Held E, Wondim DS, Gad A, Neuhoff C, Tholen E, Looft C, Schellander K, Tesfaye D, Hoelker M. Fateful triad of reactive oxygen species, mitochondrial dysfunction and lipid accumulation is associated with expression outline of the AMP-activated protein kinase pathway in bovine blastocysts. Reprod Fertil Dev 2016; 29:RD15319. [PMID: 26907741 DOI: 10.1071/rd15319] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Accepted: 12/17/2015] [Indexed: 12/11/2022] Open
Abstract
Low cryotolerance is considered as the major drawback of in vitro-produced bovine embryos and is frequently associated with a triad encompassing increased cytoplasmic lipid accumulation, enhanced levels of reactive oxygen species (ROS) and mitochondrial dysfunction. The aim of the present study was to explore the role of the AMP-activated protein kinase (AMPK) pathway in the process resulting such phenotypes. Comparative analysis under different environmental conditions revealed downregulation of AMP-activated protein kinase cytalytic subunit 1alpha (AMPKA1), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1A) and carnitine palmitoyltransferase 1 (CPT1) genes and upregulation of acetyl-CoA carboxylase α (ACC). In contrast, the presence of fatty acids within the culture medium resulted in a distinct molecular profile in the embryo associated with enhanced levels of ROS, mitochondrial dysfunction and elevated lipid accumulation in bovine embryos. Because AMPKA1 regulates PGC1A, CPT1 and ACC, the results of the present study reveal that AMPK in active its form is the key enzyme promoting lipolysis. Because AMPK1 activity is, in turn, controlled by the AMP : ATP ratio, it is possible to speculate that excessive uptake of exogenous free fatty acids could increase cellular ATP levels as a result of the disturbed β-oxidation of these external fatty acids and could therefore bypass that molecular feedback mechanism. Subsequently, this condition would cause enhanced generation of ROS, which negatively affect mitochondrial activity. Both enhanced generation of ROS and low mitochondrial activity are suggested to enhance the accumulation of lipids in bovine embryos.
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123
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Abe D, Saito T, Nogata Y. Rosmarinic Acid Regulates Fatty Acid and Glucose Utilization by Activating the CaMKK/AMPK Pathway in C2C12 Myotubes. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2016. [DOI: 10.3136/fstr.22.779] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Daigo Abe
- NARO Western Region Agricultural Research Center
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124
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Frasca D, Blomberg BB. B Cell-Specific Biomarkers for Optimal Antibody Responses to Influenza Vaccination and Molecular Pathways That Reduce B Cell Function with Aging. Crit Rev Immunol 2016; 36:523-537. [PMID: 28845758 DOI: 10.1615/critrevimmunol.2017020113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This review highlights recent findings on the effects of aging on influenza vaccine responses, with major emphasis on T and B cells, which are significantly impaired by aging. We discuss changes in T cell production and thymic output; T cell subsets; and TCR repertoire, function, and response to latent persistent infection. We also discuss changes in B cell subsets, repertoire, and function, and how function is impaired by increased intrinsic B cell inflammation and reduced signal transduction. This review presents age-related effects on antigen-presenting cells, summarizes recent studies, including our own, aimed at the identification of biomarkers of protective vaccine responses, and provides examples of recent technical advances and insights into human vaccine responses that are helping to define the features associated with successful vaccination and that may enable a more predictive vaccinology in the future.
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Affiliation(s)
- Daniela Frasca
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
| | - Bonnie B Blomberg
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL 33101, USA
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125
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Zhou X, Chen J, Chen J, Wu W, Wang X, Wang Y. The beneficial effects of betaine on dysfunctional adipose tissue and N6-methyladenosine mRNA methylation requires the AMP-activated protein kinase α1 subunit. J Nutr Biochem 2015; 26:1678-84. [DOI: 10.1016/j.jnutbio.2015.08.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 08/05/2015] [Accepted: 08/08/2015] [Indexed: 12/12/2022]
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126
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He C, Li H, Viollet B, Zou MH, Xie Z. AMPK Suppresses Vascular Inflammation In Vivo by Inhibiting Signal Transducer and Activator of Transcription-1. Diabetes 2015; 64:4285-97. [PMID: 25858560 PMCID: PMC4657575 DOI: 10.2337/db15-0107] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 03/31/2015] [Indexed: 12/14/2022]
Abstract
Activation of AMPK suppresses inflammation, but the underlying mechanisms remain poorly understood. This study was designed to characterize the molecular mechanisms by which AMPK suppresses vascular inflammation. In cultured human aortic smooth muscle cells, pharmacologic or genetic activation of AMPK inhibited the signal transducer and activator of transcription-1 (STAT1), while inhibition of AMPK had opposite effects. Deletion of AMPKα1 or AMPKα2 resulted in activation of STAT1 and in increases in proinflammatory mediators, both of which were attenuated by administration of STAT1 small interfering RNA or fludarabine, a selective STAT1 inhibitor. Moreover, AMPK activation attenuated the proinflammatory actions induced by STAT1 activators such as interferon-γ and angiotensin II (AngII). Mechanistically, we found that AMPK activation increased, whereas AMPK inhibition decreased, the levels of mitogen-activated protein kinase phosphatase-1 (MKP-1), an inducible nuclear phosphatase, by regulating proteasome-dependent degradation of MKP-1. Gene silencing of MKP-1 increased STAT1 phosphorylation and prevented 5-aminoimidazole-4-carboxyamide ribonucleoside-reduced STAT1 phosphorylation. Finally, we found that infusion of AngII caused a more severe inflammatory response in AMPKα2 knockout mouse aortas, all of which were suppressed by chronic administration of fludarabine. We conclude that AMPK activation suppresses STAT1 signaling and inhibits vascular inflammation through the upregulation of MKP-1.
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MESH Headings
- AMP-Activated Protein Kinases/antagonists & inhibitors
- AMP-Activated Protein Kinases/chemistry
- AMP-Activated Protein Kinases/genetics
- AMP-Activated Protein Kinases/metabolism
- Angiotensin II/adverse effects
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Aorta, Thoracic
- Cells, Cultured
- Dual Specificity Phosphatase 1/antagonists & inhibitors
- Dual Specificity Phosphatase 1/chemistry
- Dual Specificity Phosphatase 1/genetics
- Dual Specificity Phosphatase 1/metabolism
- Enzyme Activation/drug effects
- Humans
- Interferon-gamma/adverse effects
- MAP Kinase Signaling System/drug effects
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/immunology
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Phosphorylation/drug effects
- Protein Processing, Post-Translational/drug effects
- RNA Interference
- Random Allocation
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- STAT1 Transcription Factor/agonists
- STAT1 Transcription Factor/antagonists & inhibitors
- STAT1 Transcription Factor/genetics
- STAT1 Transcription Factor/metabolism
- Vasculitis/chemically induced
- Vasculitis/immunology
- Vasculitis/metabolism
- Vasculitis/pathology
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Affiliation(s)
- Chaoyong He
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Hongliang Li
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Benoit Viollet
- INSERM U1016, Institut Cochin, Paris, France CNRS UMR 8104, Paris, France Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Ming-Hui Zou
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
| | - Zhonglin Xie
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK
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127
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Dubon MJ, Byeon Y, Park KS. Substance P enhances the activation of AMPK and cellular lipid accumulation in 3T3‑L1 cells in response to high levels of glucose. Mol Med Rep 2015; 12:8048-54. [PMID: 26499365 PMCID: PMC4758299 DOI: 10.3892/mmr.2015.4453] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 09/25/2015] [Indexed: 12/25/2022] Open
Abstract
The rescue of glucose tolerance and insulin-sensitivity in peripheral tissues, including adipose tissue, is essential in therapeutic strategies for diabetes. The present study demonstrated that substance P (SP) increases the accumulation of lipids in 3T3-L1 cells during their differentiation into adipocytes in response to a high concentration of glucose. SP reciprocally regulated the activities of AMP-activated protein kinase (AMPK) and Akt: SP enhanced the activation of AMPK, although the activity of Akt was downregulated. Notably, SP induced an increase in the expression level of glucose transporter 4 in the 3T3-L1 adipocytes. Therefore, it is possible that SP leads to an increase in glucose uptake and the accumulation of lipids in adipocytes, and may contribute towards the rescue of insulin-sensitivity in diabetes.
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Affiliation(s)
- Maria Jose Dubon
- Department of Genetic Engineering, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi 17104, Republic of Korea
| | - Yeji Byeon
- Department of Genetic Engineering, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi 17104, Republic of Korea
| | - Ki-Sook Park
- East‑West Medical Research Institute, Kyung Hee University, Seoul 02447, Republic of Korea
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128
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Xu XJ, Apovian C, Hess D, Carmine B, Saha A, Ruderman N. Improved Insulin Sensitivity 3 Months After RYGB Surgery Is Associated With Increased Subcutaneous Adipose Tissue AMPK Activity and Decreased Oxidative Stress. Diabetes 2015; 64:3155-9. [PMID: 26001396 PMCID: PMC4542447 DOI: 10.2337/db14-1765] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 05/16/2015] [Indexed: 01/06/2023]
Abstract
Morbidly obese individuals are predisposed to a wide range of disorders, including type 2 diabetes, atherosclerotic cardiovascular disease, fatty liver disease, and certain cancers. Remarkably, all of these disorders can be improved or prevented by Roux-en-Y gastric bypass (RYGB) surgery. We have reported that decreased AMPK activity, together with increased oxidative stress and inflammation in adipose tissue, is associated with insulin resistance in morbidly obese bariatric surgery patients. In the current study, we assessed how these parameters are affected by RYGB surgery. Eleven patients (average age of 46 ± 4 years) were studied immediately prior to surgery and 3 months postoperatively. We measured subcutaneous adipose tissue AMPK phosphorylation (threonine 172, an index of its activation), malonyl-CoA content, protein carbonylation (a marker of oxidative stress), plasma adiponectin, and mRNA expression of several inflammatory cytokines. After surgery, AMPK activity increased 3.5-fold and oxidative stress decreased by 50% in subcutaneous adipose tissue. In addition, malonyl-CoA levels were reduced by 80%. Furthermore, patients had improvements in their BMI and insulin sensitivity (HOMA) and had increased circulating high-molecular weight adiponectin and decreased fasting plasma insulin levels. In contrast, the expression of inflammatory markers in subcutaneous adipose tissue was unchanged postoperatively, although plasma CRP was diminished by 50%.
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Affiliation(s)
- X Julia Xu
- Diabetes and Metabolism Unit, Section of Endocrinology, Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Caroline Apovian
- Diabetes and Metabolism Unit, Section of Endocrinology, Department of Medicine, Boston University School of Medicine, Boston, MA Nutrition and Weight Management Center, Boston University School of Medicine, Boston, MA
| | - Donald Hess
- Deparment of Surgery, Boston University School of Medicine, Boston, MA
| | - Brian Carmine
- Deparment of Surgery, Boston University School of Medicine, Boston, MA
| | - Asish Saha
- Diabetes and Metabolism Unit, Section of Endocrinology, Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Neil Ruderman
- Diabetes and Metabolism Unit, Section of Endocrinology, Department of Medicine, Boston University School of Medicine, Boston, MA
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Longo VD, Antebi A, Bartke A, Barzilai N, Brown‐Borg HM, Caruso C, Curiel TJ, Cabo R, Franceschi C, Gems D, Ingram DK, Johnson TE, Kennedy BK, Kenyon C, Klein S, Kopchick JJ, Lepperdinger G, Madeo F, Mirisola MG, Mitchell JR, Passarino G, Rudolph KL, Sedivy JM, Shadel GS, Sinclair DA, Spindler SR, Suh Y, Vijg J, Vinciguerra M, Fontana L. Interventions to Slow Aging in Humans: Are We Ready? Aging Cell 2015; 14:497-510. [PMID: 25902704 PMCID: PMC4531065 DOI: 10.1111/acel.12338] [Citation(s) in RCA: 370] [Impact Index Per Article: 41.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/11/2015] [Indexed: 12/17/2022] Open
Abstract
The workshop entitled ‘Interventions to Slow Aging in Humans: Are We Ready?’ was held in Erice, Italy, on October 8–13, 2013, to bring together leading experts in the biology and genetics of aging and obtain a consensus related to the discovery and development of safe interventions to slow aging and increase healthy lifespan in humans. There was consensus that there is sufficient evidence that aging interventions will delay and prevent disease onset for many chronic conditions of adult and old age. Essential pathways have been identified, and behavioral, dietary, and pharmacologic approaches have emerged. Although many gene targets and drugs were discussed and there was not complete consensus about all interventions, the participants selected a subset of the most promising strategies that could be tested in humans for their effects on healthspan. These were: (i) dietary interventions mimicking chronic dietary restriction (periodic fasting mimicking diets, protein restriction, etc.); (ii) drugs that inhibit the growth hormone/IGF-I axis; (iii) drugs that inhibit the mTOR–S6K pathway; or (iv) drugs that activate AMPK or specific sirtuins. These choices were based in part on consistent evidence for the pro-longevity effects and ability of these interventions to prevent or delay multiple age-related diseases and improve healthspan in simple model organisms and rodents and their potential to be safe and effective in extending human healthspan. The authors of this manuscript were speakers and discussants invited to the workshop. The following summary highlights the major points addressed and the conclusions of the meeting.
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130
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Na MK, Jeong YT, Li X, Jin F, Hwang SL, Kim GJ, Yang JH, Chang YC, Kim DS, Kim CH, Chang HW. Protective effect of butanol extracts of skin of Anguilla japonica against endoplasmic reticulum stress-induced insulin resistance via the AMPK pathway in L6 myotubes. Food Sci Biotechnol 2015. [DOI: 10.1007/s10068-015-0137-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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131
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Huang L, Fan B, Ma A, Shaul PW, Zhu H. Inhibition of ABCA1 protein degradation promotes HDL cholesterol efflux capacity and RCT and reduces atherosclerosis in mice. J Lipid Res 2015; 56:986-97. [PMID: 25761370 PMCID: PMC4409288 DOI: 10.1194/jlr.m054742] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 03/05/2015] [Indexed: 01/20/2023] Open
Abstract
ABCA1 plays a key role in the initial lipidation of apoA-I, which generates circulating HDL cholesterol. Whereas it is known that the transcriptional upregulation of ABCA1 promotes HDL formation and reverse cholesterol transport (RCT), it is not known how the inhibition of ABCA1 protein degradation impacts HDL function. Employing the small molecule triacetyl-3-hydroxyphenyladenosine (IMM-H007), we determined how the attenuation of ABCA1 protein degradation affects HDL cholesterol efflux capacity, RCT, and atherosclerotic lesion formation. Pulse-chase analysis revealed that IMM-H007 inhibits ABCA1 degradation and facilitates its cell-surface localization in macrophages, and additional studies in macrophages showed that IMM-H007 thereby promotes cholesterol efflux. IMM-H007 treatment of Paigen diet-fed mice caused an increase in circulating HDL level, it increased the cholesterol efflux capacity of HDL, and it enhanced in vivo RCT from macrophages to the plasma, liver, and feces. Furthermore, ABCA1 degradation suppression by IMM-H007 reduced atherosclerotic plaque formation in apoE(-/-) mice. Thus, via effects on both ABCA1-expressing cells and circulating HDL function, the inhibition of ABCA1 protein degradation by IMM-H007 promotes HDL cholesterol efflux capacity and RCT and attenuates atherogenesis. IMM-H007 potentially represents a lead compound for the development of agents to augment HDL function.
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Affiliation(s)
- LinZhang Huang
- State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - BaoYan Fan
- State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ang Ma
- State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Philip W. Shaul
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX
| | - HaiBo Zhu
- State Key Laboratory for Bioactive Substances and Functions of Natural Medicines, Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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132
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Zeng HL, Huang SL, Xie FC, Zeng LM, Hu YH, Leng Y. Yhhu981, a novel compound, stimulates fatty acid oxidation via the activation of AMPK and ameliorates lipid metabolism disorder in ob/ob mice. Acta Pharmacol Sin 2015; 36:343-52. [PMID: 25732571 DOI: 10.1038/aps.2014.147] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 12/08/2014] [Indexed: 02/07/2023] Open
Abstract
AIM Defects in fatty acid metabolism contribute to the pathogenesis of insulin resistance and obesity. In this study, we investigated the effects of a novel compound yhhu981 on fatty acid metabolism in vitro and in vivo. METHODS The capacity to stimulate fatty acid oxidation was assessed in C2C12 myotubes. The fatty acid synthesis was studied in HepG2 cells using isotope tracing. The phosphorylation of AMPK and acetyl-CoA carboxylase (ACC) was examined with Western blot analysis. For in vivo experiments, ob/ob mice were orally treated with yhhu981 acutely (300 mg/kg) or chronically (150 or 300 mg·kg(-1)·d(-1) for 22 d). On the last day of treatment, serum and tissue samples were collected for analysis. RESULTS Yhhu981 (12.5-25 μmol/L) significantly increased fatty acid oxidation and the expression of related genes (Sirt1, Pgc1α and Mcad) in C2C12 myotubes, and inhibited fatty acid synthesis in HepG2 cells. Furthermore, yhhu981 dose-dependently increased the phosphorylation of AMPK and ACC in both C2C12 myotubes and HepG2 cells. Compound C, an AMPK inhibitor, blocked fatty acid oxidation in yhhu981-treated C2C12 myotubes and fatty acid synthesis decrease in yhhu981-treated HepG2 cells. Acute administration of yhhu981 decreased the respiratory exchange ratio in ob/ob mice, whereas chronic treatment with yhhu981 ameliorated the lipid abnormalities and ectopic lipid deposition in skeletal muscle and liver of ob/ob mice. CONCLUSION Yhhu981 is a potent compound that stimulates fatty acid oxidation, and exerts pleiotropic effects on lipid metabolism by activating AMPK.
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Nolan CJ, Ruderman NB, Kahn SE, Pedersen O, Prentki M. Insulin resistance as a physiological defense against metabolic stress: implications for the management of subsets of type 2 diabetes. Diabetes 2015; 64:673-86. [PMID: 25713189 PMCID: PMC4338588 DOI: 10.2337/db14-0694] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stratifying the management of type 2 diabetes (T2D) has to take into account marked variability in patient phenotype due to heterogeneity in its pathophysiology, different stages of the disease process, and multiple other patient factors including comorbidities. The focus here is on the very challenging subgroup of patients with T2D who are overweight or obese with insulin resistance (IR) and the most refractory hyperglycemia due to an inability to change lifestyle to reverse positive energy balance. For this subgroup of patients with T2D, we question the dogma that IR is primarily harmful to the body and should be counteracted at any cost. Instead we propose that IR, particularly in this high-risk subgroup, is a defense mechanism that protects critical tissues of the cardiovascular system from nutrient-induced injury. Overriding IR in an effort to lower plasma glucose levels, particularly with intensive insulin therapy, could therefore be harmful. Treatments that nutrient off-load to lower glucose are more likely to be beneficial. The concepts of "IR as an adaptive defense mechanism" and "insulin-induced metabolic stress" may provide explanation for some of the unexpected outcomes of recent major clinical trials in T2D. Potential molecular mechanisms underlying these concepts; their clinical implications for stratification of T2D management, particularly in overweight and obese patients with difficult glycemic control; and future research requirements are discussed.
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Affiliation(s)
- Christopher J Nolan
- Department of Endocrinology at Canberra Hospital and the Australian National University Medical School, Canberra, Australia
| | - Neil B Ruderman
- Diabetes Research Unit, Boston University Medical Center, Boston, MA
| | - Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, VA Puget Sound Health Care System, and University of Washington, Seattle, WA
| | - Oluf Pedersen
- Novo Nordisk Foundation Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marc Prentki
- CRCHUM and Montreal Diabetes Research Center and Departments of Nutrition and Biochemistry and Molecular Medicine, University of Montreal, Quebec, Canada
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134
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Huang M, Wang F, Zhou X, Yang H, Wang Y. Hypoglycemic and hypolipidemic properties of polysaccharides from Enterobacter cloacae Z0206 in KKAy mice. Carbohydr Polym 2015; 117:91-98. [DOI: 10.1016/j.carbpol.2014.09.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 08/11/2014] [Accepted: 09/07/2014] [Indexed: 12/25/2022]
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135
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Hirschey MD, Zhao Y. Metabolic Regulation by Lysine Malonylation, Succinylation, and Glutarylation. Mol Cell Proteomics 2015; 14:2308-15. [PMID: 25717114 DOI: 10.1074/mcp.r114.046664] [Citation(s) in RCA: 308] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Indexed: 12/14/2022] Open
Abstract
Protein acetylation is a well-studied regulatory mechanism for several cellular processes, ranging from gene expression to metabolism. Recent discoveries of new post-translational modifications, including malonylation, succinylation, and glutarylation, have expanded our understanding of the types of modifications found on proteins. These three acidic lysine modifications are structurally similar but have the potential to regulate different proteins in different pathways. The deacylase sirtuin 5 (SIRT5) catalyzes the removal of these modifications from a wide range of proteins in different subcellular compartments. Here, we review these new modifications, their regulation by SIRT5, and their emerging role in cellular regulation and diseases.
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Affiliation(s)
- Matthew D Hirschey
- From the ‡Duke Molecular Physiology Institute, Sarah W. Stedman Metabolism and Nutrition Center, §Departments of Medicine & Pharmacology and Cancer Biology, Duke University, Medical Center, Durham, NC 27710;
| | - Yingming Zhao
- ¶Ben May Department for Cancer Research, The University of Chicago, Chicago, IL 60637
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136
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He Z, Peng Y, Duan W, Tian Y, Zhang J, Hu T, Cai Y, Feng Y, Li G. Aspirin regulates hepatocellular lipid metabolism by activating AMPK signaling pathway. J Toxicol Sci 2015; 40:127-36. [PMID: 25743752 DOI: 10.2131/jts.40.127] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Zhenxing He
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Yong Peng
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Wentao Duan
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Yunhong Tian
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Jian Zhang
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Tao Hu
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Yu Cai
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Yuan Feng
- Department of Hepatopancreatobiliary Surgery, Nanchong Central Hospital, China
| | - Guangming Li
- Department of Oncology, Nanchong Central Hospital, China
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137
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Downs SM. Nutrient pathways regulating the nuclear maturation of mammalian oocytes. Reprod Fertil Dev 2015; 27:572-82. [DOI: 10.1071/rd14343] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 01/10/2015] [Indexed: 12/15/2022] Open
Abstract
Oocyte maturation is defined as that phase of development whereby a fully grown oocyte reinitiates meiotic maturation, completes one meiotic division with extrusion of a polar body, then arrests at MII until fertilisation. Completion of maturation depends on many different factors, not the least of which is the proper provision of energy substrates to fuel the process. Interaction of the oocyte and somatic compartment of the follicle is critical and involves numerous signals exchanged between the two cell types in both directions. One of the prominent functions of the cumulus cells is the channelling of metabolites and nutrients to the oocyte to help stimulate germinal vesicle breakdown and direct development to MII. This entails the careful integration and coordination of numerous metabolic pathways, as well as oocyte paracrine signals that direct certain aspects of cumulus cell metabolism. These forces collaborate to produce a mature oocyte that, along with accompanying physiological changes called cytoplasmic maturation, which impart subsequent developmental competence to the oocyte, can be fertilised and develop to term. This review focuses on nuclear maturation and the metabolic interplay that regulates it, with special emphasis on data generated in the mouse.
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138
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Hong SW, Lee J, Park SE, Rhee EJ, Park CY, Oh KW, Park SW, Lee WY. Activation of AMP-Activated Protein Kinase Attenuates Tumor Necrosis Factor-α-Induced Lipolysis via Protection of Perilipin in 3T3-L1 Adipocytes. Endocrinol Metab (Seoul) 2014; 29:553-60. [PMID: 25325265 PMCID: PMC4285046 DOI: 10.3803/enm.2014.29.4.553] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/11/2014] [Accepted: 04/24/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Tumor necrosis factor (TNF)-α and AMP-activated protein kinase (AMPK) are known to stimulate and repress lipolysis in adipocytes, respectively; however, the mechanisms regulating these processes have not been completely elucidated. METHODS The key factors and mechanism of action of TNF-α and AMPK in lipolysis were investigated by evaluating perilipin expression and activity of protein kinase RNA-like endoplasmic reticulum kinase (PERK)/eukaryotic initiation factor 2 α (eIF2α) by Western blot and an immunofluorescence assay in 24-hour TNF-α-treated 3T3-L1 adipocytes with artificial manipulation of AMPK activation. RESULTS Enhancement of AMPK activity by the addition of activator minoimidazole carboxamide ribonucleotide (AICAR) suppressed TNF-α-induced lipolysis, whereas the addition of compound C, an inhibitor of AMPK phosphorylation, enhanced lipolysis. Perilipin, a lipid droplet-associated protein, was decreased by TNF-α and recovered following treatment with AICAR, showing a correlation with the antilipolytic effect of AICAR. Significant activation of PERK/eIF2α, a component of the unfolded protein response signaling pathway, was observed in TNF-α or vesicle-treated 3T3-L1 adipocytes. The antilipolytic effect and recovery of perilipin expression by AICAR in TNF-α-treated 3T3-L1 adipocytes were significantly diminished by treatment with 2-aminopurine, a specific inhibitor of eIF2α. CONCLUSION These data indicated that AICAR-induced AMPK activation attenuates TNF-α-induced lipolysis via preservation of perilipin in 3T3-L1 adipocytes. In addition, PERK/eIF2α activity is a novel mechanism of the anti-lipolytic effect of AICAR.
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Affiliation(s)
- Seok Woo Hong
- Institute of Medical Research, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jinmi Lee
- Institute of Medical Research, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Se Eun Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Eun Jung Rhee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Cheol Young Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Ki Won Oh
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sung Woo Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Won Young Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
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139
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García-Prieto CF, Pulido-Olmo H, Ruiz-Hurtado G, Gil-Ortega M, Aranguez I, Rubio MA, Ruiz-Gayo M, Somoza B, Fernández-Alfonso MS. Mild caloric restriction reduces blood pressure and activates endothelial AMPK-PI3K-Akt-eNOS pathway in obese Zucker rats. Vascul Pharmacol 2014; 65-66:3-12. [PMID: 25530153 DOI: 10.1016/j.vph.2014.12.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/08/2014] [Accepted: 12/04/2014] [Indexed: 10/24/2022]
Abstract
Genetic obesity models exhibit endothelial dysfunction associated to adenosine monophosphate-activated protein kinase (AMPK) dysregulation. This study aims to assess if mild short-term caloric restriction (CR) restores endothelial AMPK activity leading to an improvement in endothelial function. Twelve-week old Zucker lean and obese (fa/fa) male rats had access to standard chow either ad libitum (AL, n=8) or 80% of AL (CR, n=8) for two weeks. Systolic blood pressure was significantly higher in fa/fa AL rats versus lean AL animals, but was normalized by CR. Endothelium-dependent relaxation to acetylcholine (ACh, 10(-9) to 10(-4) M) was reduced in fa/fa AL compared to control lean AL rats (p<0.001), and restored by CR. The AMPK activator AICAR (10(-5) to 8·10(-3) M) elicited a lower relaxation in fa/fa AL rings that was normalized by CR (p<0.001). Inhibition of PI3K (wortmannin, 10(-7) M), Akt (triciribine, 10(-5) M), or eNOS (L-NAME, 10(-4) M) markedly reduced AICAR-induced relaxation in lean AL, but not in fa/fa AL rats. These inhibitions were restored by CR in Zucker fa/fa rings. These data show that mild short-term CR improves endothelial function and lowers blood pressure in obesity due to the activation of the AMPK-PI3K-Akt-eNOS pathway.
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Affiliation(s)
- C F García-Prieto
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, 28668 Madrid, Spain
| | - H Pulido-Olmo
- Instituto Pluridisciplinar and Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain; Unidad de Hipertensión, imas12, Hospital 12 de Octubre, 28041 Madrid, Spain
| | - G Ruiz-Hurtado
- Instituto Pluridisciplinar and Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain; Unidad de Hipertensión, imas12, Hospital 12 de Octubre, 28041 Madrid, Spain
| | - M Gil-Ortega
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, 28668 Madrid, Spain
| | - I Aranguez
- Instituto Pluridisciplinar and Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain; Departamento de Bioquímica, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain
| | - M A Rubio
- Servicio de Endocrinología y Nutrición, Hospital Clínico San Carlos, IdISSC, 28040 Madrid, Spain
| | - M Ruiz-Gayo
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, 28668 Madrid, Spain
| | - B Somoza
- Departamento de Ciencias Farmacéuticas y de la Salud, Facultad de Farmacia, Universidad CEU-San Pablo, 28668 Madrid, Spain
| | - M S Fernández-Alfonso
- Instituto Pluridisciplinar and Departamento de Farmacología, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain.
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Lin YC, Wu MH, Wei TT, Lin YC, Huang WC, Huang LY, Lin YT, Chen CC. Metformin sensitizes anticancer effect of dasatinib in head and neck squamous cell carcinoma cells through AMPK-dependent ER stress. Oncotarget 2014; 5:298-308. [PMID: 24457597 PMCID: PMC3960210 DOI: 10.18632/oncotarget.1628] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Head and neck squamous cell carcinoma (HNSCC) is an important endemic disease in Taiwan with aggressive course and dismal outcome. Dasatinib is a Bcr-bl and Src kinase inhibitor that has potential against HNSCC. We recently disclosed that EGFR degradation is critical for dasatinib-induced apoptosis. Here, we further demonstrate that AMPK-dependent ER stress is responsible for this event. Dasatinib induced ER stress which mediated EGFR degradation in a c-cbl-dependent manner. AMPK activation induced by dasatinib might be due to ATP decrease through the up-regulation of pyruvate dehydrogenase kinase 4 (PDK4). Furthermore, activation of AMPK by metformin sensitized dasatinib-induced in vitro and in vivo anti-cancer effect. The correlation of AMPK activation and EGFR expression was seen in HNSCC cells and human tumor specimens. Our results disclose that AMPK-dependent ER stress plays a crucial role in the anti-cancer effect of dasatinib in HNSCC and further activation of AMPK by metformin might enhance dasatinib efficacy.
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141
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Reduced oxidative stress contributes to the lipid lowering effects of isoquercitrin in free fatty acids induced hepatocytes. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:313602. [PMID: 25404990 PMCID: PMC4227458 DOI: 10.1155/2014/313602] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 07/03/2014] [Indexed: 02/06/2023]
Abstract
Oxidative stress interferes with hepatic lipid metabolism at various levels ranging from benign lipid storage to so-called second hit of inflammation activation. Isoquercitrin (IQ) is widely present flavonoid but its effects on hepatic lipid metabolism remain unknown. We used free fatty acids (FFA) induced lipid overload and oxidative stress model in two types of liver cells and measured cell viability, intracellular lipids, and reactive oxygen species (ROS) within hepatocytes. In addition, Intracellular triglycerides (TG), superoxide dismutase (SOD), and malondialdehyde (MDA) were examined. A novel in vitro model was used to evaluate correlation between lipid lowering and antioxidative activities. Furthermore, 34 major cytokines and corresponding ROS levels were analyzed in FFA/LPS induced coculture model between hepatocytes and Kupffer cells. At molecular level AMPK pathway was elucidated. We showed that IQ attenuated FFA induced lipid overload and ROS within hepatocytes. Further, IQ reversed FFA induced increase in intracellular TG SOD and MDA. It was shown that antioxidative activity of IQ correlates with its lipid lowering potentials. IQ reversed major proinflammatory cytokines and oxidative stress in FFA/LPS induced coculture model. Finally, AMPK pathway was found responsible for metabolic benefits at molecular level. IQ strikingly manifests antioxidative and related lipid lowering activities in hepatocytes.
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142
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Treatment of Nonalcoholic Fatty Liver Disease with Total Alkaloids in Rubus aleaefolius Poir through Regulation of Fat Metabolism. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2014; 2014:768540. [PMID: 25404949 PMCID: PMC4212541 DOI: 10.1155/2014/768540] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 08/07/2014] [Indexed: 12/14/2022]
Abstract
Total alkaloids in Rubus aleaefolius Poir (TARAP) is a folk medicinal herb that has been used clinically in China to treat nonalcoholic fatty liver disease (NAFLD) for many years. However, the mechanism of its anti-NAFLD effect is largely unknown. In this study, we developed a NAFLD rat model by supplying a modified high-fat diet (mHFD) ad libitum for 8 weeks and evaluated the therapeutic effect of TARAP in NAFLD rats as well as the underlying molecular mechanism. We found that TARAP could reduce the serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein (LDL-C) levels and increase the serum high-density lipoprotein (HDL-C) level in NAFLD rats. In addition, TARAP treatment reduced expression of fatty acid synthetase (FAS), and acetyl-CoA carboxylase (ACC) and upregulated the expression of carnitine palmitoyltransferase (CPT). Our results suggest that regulation of lipid metabolism may be a mechanism by which TARAP treats NAFLD.
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Liu X, Hao JJ, Zhang LJ, Zhao X, He XX, Li MM, Zhao XL, Wu JD, Qiu PJ, Yu GL. Activated AMPK explains hypolipidemic effects of sulfated low molecular weight guluronate on HepG2 cells. Eur J Med Chem 2014; 85:304-10. [DOI: 10.1016/j.ejmech.2014.07.107] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 07/28/2014] [Accepted: 07/29/2014] [Indexed: 11/28/2022]
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144
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Short and long-term impact of lipectomy on expression profile of hepatic anabolic genes in rats: a high fat and high cholesterol diet-induced obese model. PLoS One 2014; 9:e108717. [PMID: 25264921 PMCID: PMC4181868 DOI: 10.1371/journal.pone.0108717] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 09/02/2014] [Indexed: 01/05/2023] Open
Abstract
Objective To understand the molecular basis of the short and long-term effects of an immediate shortage of energy storage caused by lipectomy on expression profile of genes involved in lipid and carbohydrate metabolism in high fat and high cholesterol diet-induced obese rats. Methods The hepatic mRNA levels of enzymes, regulator and transcription factors involved in glucose and lipid metabolism were analyzed by quantitative real time polymerase chain reaction (RT-qPCR) ten days and eight weeks after lipectomy in obese rats. Body and liver weights and serum biochemical parameters, adiponectin, leptin and insulin were determined. Results No significant difference was observed on the food intake between the lipectomized and sham-operated groups during the experimental period. Ten days after the operation, the lipectomized animals showed significant higher triacylglycerol, glucose and insulin levels, a lower adiponectin concentration than the sham-operated rats, along with significant higher hepatic mRNA levels of hepatocyte nuclear factor 4α (HNF4α) and the enzymes involved in lipogenesis, sterol biosynthesis and gluconeogenesis. The results of immunohistochemical (IHC) analysis also confirmed increased levels of lipogenic enzymes in the liver of lipectomized versus sham-operated animals. The lipectomized group had a significantly lower adiponectin/leptin ratio that was positively correlated to the level of LDL (r = 0.823, P<0.05) and negatively to glucose and insulin (r = −0.821 and −0.892 respectively, P<0.05). Eight weeks after the operation, the lipectomized animals revealed significant higher body and liver weights, weight gain, liver to body weight ratio, hepatic triacylglycerol and serum insulin level. Conclusions In response to lipectomy a short term enhancement of the expression of hepatic anabolic genes involved in lipid and carbohydrate metabolism was triggered that might eventually lead to the final extra weight gain. These metabolic changes could be the results of reduced circulating adiponectin that further influences the functions of insulin and hepatic HNF4α.
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145
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Kwon Y, Song P, Yoon JH, Ghim J, Kim D, Kang B, Lee TG, Kim JA, Choi JK, Youn IK, Lee HK, Ryu SH. Xanthene derivatives increase glucose utilization through activation of LKB1-dependent AMP-activated protein kinase. PLoS One 2014; 9:e108771. [PMID: 25250787 PMCID: PMC4177559 DOI: 10.1371/journal.pone.0108771] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 08/25/2014] [Indexed: 12/25/2022] Open
Abstract
5′ AMP-activated protein kinase (AMPK) is a highly conserved serine-threonine kinase that regulates energy expenditure by activating catabolic metabolism and suppressing anabolic pathways to increase cellular energy levels. Therefore AMPK activators are considered to be drug targets for treatment of metabolic diseases such as diabetes mellitus. To identify novel AMPK activators, we screened xanthene derivatives. We determined that the AMPK activators 9H-xanthene-9-carboxylic acid {2,2,2-trichloro-1-[3-(3-nitro-phenyl)-thioureido]-ethyl}-amide (Xn) and 9H-xanthene-9-carboxylic acid {2,2,2-trichloro-1-[3-(3-cyano-phenyl)-thioureido]-ethyl}-amide (Xc) elevated glucose uptake in L6 myotubes by stimulating translocation of glucose transporter type 4 (GLUT4). Treatment with the chemical AMPK inhibitor compound C and infection with dominant-negative AMPKa2-virus inhibited AMPK phosphorylation and glucose uptake in myotubes induced by either Xn or Xc. Of the two major upstream kinases of AMPK, we found that Xn and Xc showed LKB1 dependency by knockdown of STK11, an ortholog of human LKB1. Single intravenous administration of Xn and Xc to high-fat diet-induced diabetic mice stimulated AMPK phosphorylation of skeletal muscle and improved glucose tolerance. Taken together, these results suggest that Xn and Xc regulate glucose homeostasis through LKB1-dependent AMPK activation and that the compounds are potential candidate drugs for the treatment of type 2 diabetes mellitus.
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Affiliation(s)
- Yonghoon Kwon
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
| | - Parkyong Song
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
| | - Jong Hyuk Yoon
- NovaCell Technology Inc., Pohang, Kyungbuk, Republic of Korea
| | - Jaewang Ghim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
| | - Dayea Kim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
| | - Byungjun Kang
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
| | - Taehoon G. Lee
- NovaCell Technology Inc., Pohang, Kyungbuk, Republic of Korea
| | - Jin-Ah Kim
- Korea Chemical Bank, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Joong-Kwon Choi
- Korea Chemical Bank, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - In Kwon Youn
- Department of Pharmaceutical Engineering, Pai Chai University, Daejeon, Republic of Korea
| | - Hyeon-Kyu Lee
- Korea Chemical Bank, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Kyungbuk, Republic of Korea
- * E-mail:
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146
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Zingiber officinale (Ginger): A Future Outlook on Its Potential in Prevention and Treatment of Diabetes and Prediabetic States. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/674684] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Diabetes is reaching pandemic levels in both developing and developed countries and requires safe, affordable, and effective therapies. This report summarises work in our laboratory on the effects of Zingiber officinale (ginger) and its components in diabetes models and provides a future outlook on the potential for their use in type 2 diabetes. A high fat diet rat model showed modulation of body weight gain and normalisation of glucose and lipid metabolic disturbances, with reduction of insulin resistance in a high fat-high carbohydrate diet model. Ginger extract inhibits enhanced NF-κB in liver of high fat-fed rats through inhibition of the IKK/IκBα/NF-κB classical pathway. The major active component (S)-[6]-gingerol inhibited elevated cytokines in inflamed HuH7 cells through suppression of COX2 expression and protection against the ROS pathway. Ginger extract and gingerols enhanced glucose uptake in L6 myotubes, by enhancing translocation of GLUT4 to the surface membrane and activation of AMPKα1 through a Ca2+/calmodulin-dependent protein kinase kinase pathway. (S)-[6]-Gingerol also enhanced energy metabolism through marked increment of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) gene expression and mitochondrial content in L6 skeletal muscle cells. Future studies will require well designed clinical trials on ginger preparations of defined chemical composition.
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147
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Zhu W, Chen S, Li Z, Zhao X, Li W, Sun Y, Zhang Z, Ling W, Feng X. Effects and mechanisms of resveratrol on the amelioration of oxidative stress and hepatic steatosis in KKAy mice. Nutr Metab (Lond) 2014; 11:35. [PMID: 25140191 PMCID: PMC4137107 DOI: 10.1186/1743-7075-11-35] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 08/06/2014] [Indexed: 02/07/2023] Open
Abstract
Background The exact mechanism of the protective role of Resveratrol (Res) in lipid metabolism and oxidative stress is not well elucidated. The present study aimed to investigate the potential benefits and possible mechanisms of Res on the amelioration of oxidative stress and hepatic steatosis in a KKAy mouse model. Methods A total of 30 KKAy male mice were randomly divided into three groups: a normal chow group, a low resveratrol group and a high resveratrol group. After a 12-wk study period, serum levels of TG, TC, LDL-C and HDL-C, the liver content of TG and TC, ROS, GSH, GPx, SOD and MDA levels were measured. Ectopic lipid deposition was observed in sectioned frozen liver tissues. The mRNA levels of ATGL and HSL in the liver tissues were determined via real-time PCR. Furthermore, the protein expression of p47phox, gp91phox, ATGL, HSL, Sirt1, AMPK and FOXO1 were analyzed using western blotting. Results Following Res supplementation, serum levels of TG and MDA were decreased, while the HDL-C and SOD levels were increased in KKAy mice. Furthermore, Res treatment increased GSH and GPx in liver tissues, while it decreased ROS. In addition, Res significantly reduced hepatic steatosis. After Res treatment, concentrations of p47phox (membrane) and gp91phox proteins were reduced, while p-HSL, HSL and ATGL protein expression levels were increased. Mechanistically, the levels of Sirt1, p-AMPK and p-FOXO1 expression in the liver tissues were up-regulated following supplementation with Res, and FOXO1 protein was released from the nucleus into the cytoplasm. Conclusions Res is able to attenuate hepatic steatosis and lipid metabolic disorder and enhance the antioxidant ability in KKAy mice, possibly by up-regulating Sirt1 expression and the phosphorylation of AMPK.
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Affiliation(s)
- Wei Zhu
- Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, People's Republic of China
| | - Sifan Chen
- School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong, People's Republic of China.,Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, People's Republic of China
| | - Zilun Li
- Division of Vascular Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China
| | - Xiaohong Zhao
- Department of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China
| | - Wenxue Li
- Guangzhou Center for Disease Control and Prevention, Guangzhou, Guangdong, People's Republic of China
| | - Yanshuang Sun
- School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong, People's Republic of China
| | - Zili Zhang
- School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong, People's Republic of China
| | - Wenhua Ling
- School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong, People's Republic of China
| | - Xiang Feng
- School of Public Health, Sun Yat-Sen University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Provincial Key Laboratory of Food, Nutrition and Health, Guangzhou, Guangdong, People's Republic of China
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148
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Coughlan KA, Valentine RJ, Ruderman NB, Saha AK. AMPK activation: a therapeutic target for type 2 diabetes? Diabetes Metab Syndr Obes 2014; 7:241-53. [PMID: 25018645 PMCID: PMC4075959 DOI: 10.2147/dmso.s43731] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Type 2 diabetes (T2D) is a metabolic disease characterized by insulin resistance, β-cell dysfunction, and elevated hepatic glucose output. Over 350 million people worldwide have T2D, and the International Diabetes Federation projects that this number will increase to nearly 600 million by 2035. There is a great need for more effective treatments for maintaining glucose homeostasis and improving insulin sensitivity. AMP-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase whose activation elicits insulin-sensitizing effects, making it an ideal therapeutic target for T2D. AMPK is an energy-sensing enzyme that is activated when cellular energy levels are low, and it signals to stimulate glucose uptake in skeletal muscles, fatty acid oxidation in adipose (and other) tissues, and reduces hepatic glucose production. There is substantial evidence suggesting that AMPK is dysregulated in animals and humans with metabolic syndrome or T2D, and that AMPK activation (physiological or pharmacological) can improve insulin sensitivity and metabolic health. Numerous pharmacological agents, natural compounds, and hormones are known to activate AMPK, either directly or indirectly - some of which (for example, metformin and thiazolidinediones) are currently used to treat T2D. This paper will review the regulation of the AMPK pathway and its role in T2D, some of the known AMPK activators and their mechanisms of action, and the potential for future improvements in targeting AMPK for the treatment of T2D.
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Affiliation(s)
- Kimberly A Coughlan
- Endocrinology and Diabetes, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Rudy J Valentine
- Endocrinology and Diabetes, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Neil B Ruderman
- Endocrinology and Diabetes, Department of Medicine, Boston University Medical Center, Boston, MA, USA
| | - Asish K Saha
- Endocrinology and Diabetes, Department of Medicine, Boston University Medical Center, Boston, MA, USA
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149
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Abstract
Pancreatic β-cell function is of critical importance in the regulation of fuel homoeostasis, and metabolic dysregulation is a hallmark of diabetes mellitus (DM). The β-cell is an intricately designed cell type that couples metabolism of dietary sources of carbohydrates, amino acids and lipids to insulin secretory mechanisms, such that insulin release occurs at appropriate times to ensure efficient nutrient uptake and storage by target tissues. However, chronic exposure to high nutrient concentrations results in altered metabolism that impacts negatively on insulin exocytosis, insulin action and may ultimately lead to development of DM. Reduced action of insulin in target tissues is associated with impairment of insulin signalling and contributes to insulin resistance (IR), a condition often associated with obesity and a major risk factor for DM. The altered metabolism of nutrients by insulin-sensitive target tissues (muscle, adipose tissue and liver) can result in high circulating levels of glucose and various lipids, which further impact on pancreatic β-cell function, IR and progression of the metabolic syndrome. Here, we have considered the role played by the major nutrient groups, carbohydrates, amino acids and lipids, in mediating β-cell insulin secretion, while also exploring the interplay between amino acids and insulin action in muscle. We also focus on the effects of altered lipid metabolism in adipose tissue and liver resulting from activation of inflammatory processes commonly observed in DM pathophysiology. The aim of this review is to describe commonalities and differences in metabolism related to insulin secretion and action, pertinent to the development of DM.
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Affiliation(s)
- Philip Newsholme
- School of Biomedical SciencesCHIRI Biosciences Research Precinct, Curtin University, GPO Box U1987, Perth, Western Australia, Australia
| | - Vinicius Cruzat
- School of Biomedical SciencesCHIRI Biosciences Research Precinct, Curtin University, GPO Box U1987, Perth, Western Australia, Australia
| | - Frank Arfuso
- School of Biomedical SciencesCHIRI Biosciences Research Precinct, Curtin University, GPO Box U1987, Perth, Western Australia, Australia
| | - Kevin Keane
- School of Biomedical SciencesCHIRI Biosciences Research Precinct, Curtin University, GPO Box U1987, Perth, Western Australia, Australia
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150
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Dahlhoff C, Worsch S, Sailer M, Hummel BA, Fiamoncini J, Uebel K, Obeid R, Scherling C, Geisel J, Bader BL, Daniel H. Methyl-donor supplementation in obese mice prevents the progression of NAFLD, activates AMPK and decreases acyl-carnitine levels. Mol Metab 2014; 3:565-80. [PMID: 25061561 PMCID: PMC4099513 DOI: 10.1016/j.molmet.2014.04.010] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/25/2014] [Accepted: 04/30/2014] [Indexed: 12/31/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) results from increased hepatic lipid accumulation and steatosis, and is closely linked to liver one-carbon (C1) metabolism. We assessed in C57BL6/N mice whether NAFLD induced by a high-fat (HF) diet over 8 weeks can be reversed by additional 4 weeks of a dietary methyl-donor supplementation (MDS). MDS in the obese mice failed to reverse NAFLD, but prevented the progression of hepatic steatosis associated with major changes in key hepatic C1-metabolites, e.g. S-adenosyl-methionine and S-adenosyl-homocysteine. Increased phosphorylation of AMPK-α together with enhanced β-HAD activity suggested an increased flux through fatty acid oxidation pathways. This was supported by concomitantly decreased hepatic free fatty acid and acyl-carnitines levels. Although HF diet changed the hepatic phospholipid pattern, MDS did not. Our findings suggest that dietary methyl-donors activate AMPK, a key enzyme in fatty acid β-oxidation control, that mediates increased fatty acid utilization and thereby prevents further hepatic lipid accumulation.
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Key Words
- 3-HB, β-hydroxybutyrate
- ACC, acetyl-CoA carboxylase
- AMP-activated protein kinase
- AMPK, AMP-activated protein kinase
- ANT, adenine nucleotide translocase
- Acyl-carnitines
- Bhmt, betaine-homocysteine methyltransferase
- C, control diet
- C1, one-carbon
- CACT, carnitine-acylcarnitine transporter
- CMS, methyl-donor supplemented control diet
- Cbs, cystathionine β-synthase
- Cpt1a, carnitine palmitoyltransferase-1a
- DIO, diet-induced obesity
- Fasn, fatty acid synthase
- GNMT, glycine N-methyltransferase
- Gapdh, glyceraldehyde 3-phosphate dehydrogenase
- HF, high-fat diet
- HFMS, methyl-donor supplemented high-fat diet
- HMW adiponectin, high molecular weight adiponectin
- HSP90, heat shock protein 90
- Hcy, homocysteine
- Hepatic steatosis
- Hprt1, hypoxanthine phosphoribosyltransferase 1
- LDL, low density lipoprotein
- MAT, methionine adenosyltransferase
- MCD, malonyl-CoA decarboxylase
- MDS, methyl-donor supplementation
- MTR, methionine synthase
- NAFLD, non-alcoholic fatty liver disease
- NEFA, non-esterified fatty acids
- Obesity
- One-carbon metabolism
- PC, phosphatidylcholine
- PGC1α, peroxisome proliferator-activated receptor-γ co-activator-1α
- PL, phospholipids
- PPARα, peroxisome proliferator-activated receptor-α
- Pemt, phosphatidylethanolamine methyltransferase
- SAH, S-adenosylhomocysteine
- SAM, S-adenosylmethionine
- SM, sphingomyelin
- SREBP1c, sterol regulatory element-binding protein-1c
- TG, triacylglycerol
- VAT, visceral adipose tissue
- VLDL, very low density lipoprotein
- β-HAD, β-hydroxyacyl CoA dehydrogenase
- β-oxidation
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Affiliation(s)
- Christoph Dahlhoff
- Biochemistry Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany ; PhD Group - Epigenetics, Imprinting and Nutrition, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Stefanie Worsch
- Nutritional Medicine Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Manuela Sailer
- Biochemistry Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Björn A Hummel
- Clinical Chemistry and Laboratory Medicine/Central Laboratory, University Hospital of the Saarland, 66421 Homburg, Germany ; Clinical Haemostasiology and Transfusion Medicine, University Hospital of the Saarland, 66421 Homburg, Germany
| | - Jarlei Fiamoncini
- Biochemistry Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Kirsten Uebel
- Nutritional Medicine Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Rima Obeid
- Clinical Chemistry and Laboratory Medicine/Central Laboratory, University Hospital of the Saarland, 66421 Homburg, Germany
| | - Christian Scherling
- Biochemistry Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Jürgen Geisel
- Clinical Chemistry and Laboratory Medicine/Central Laboratory, University Hospital of the Saarland, 66421 Homburg, Germany
| | - Bernhard L Bader
- PhD Group - Epigenetics, Imprinting and Nutrition, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany ; Nutritional Medicine Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
| | - Hannelore Daniel
- Biochemistry Unit, Research Center for Nutrition and Food Sciences (ZIEL), Technische Universität München, 85350 Freising-Weihenstephan, Germany
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