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Zou B, Ge ZZ, Zhang Y, Du J, Xu Z, Li CM. Persimmon Tannin accounts for hypolipidemic effects of persimmon through activating of AMPK and suppressing NF-κB activation and inflammatory responses in High-Fat Diet Rats. Food Funct 2014; 5:1536-46. [DOI: 10.1039/c3fo60635j] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High molecular weight persimmon tannin is a central component accounting for the anti-hyperlipidemic effects of consuming persimmon fruits via AMPK pathway.
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Affiliation(s)
- Bo Zou
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
| | - Zhen-zhen Ge
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
| | - Ying Zhang
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
| | - Jing Du
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
| | - Ze Xu
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
| | - Chun-mei Li
- College of Food Science and Technology
- Huazhong Agricultural University
- Wuhan, China
- Key Laboratory of Environment Correlative Food Science (Huazhong Agricultural University)
- Ministry of Education
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202
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Saks V, Schlattner U, Tokarska-Schlattner M, Wallimann T, Bagur R, Zorman S, Pelosse M, Santos PD, Boucher F, Kaambre T, Guzun R. Systems Level Regulation of Cardiac Energy Fluxes Via Metabolic Cycles: Role of Creatine, Phosphotransfer Pathways, and AMPK Signaling. SYSTEMS BIOLOGY OF METABOLIC AND SIGNALING NETWORKS 2014. [DOI: 10.1007/978-3-642-38505-6_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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203
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Mercer JR. Mitochondrial bioenergetics and therapeutic intervention in cardiovascular disease. Pharmacol Ther 2014; 141:13-20. [DOI: 10.1016/j.pharmthera.2013.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 07/18/2013] [Indexed: 11/15/2022]
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204
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Figarola JL, Singhal P, Rahbar S, Gugiu BG, Awasthi S, Singhal SS. COH-SR4 reduces body weight, improves glycemic control and prevents hepatic steatosis in high fat diet-induced obese mice. PLoS One 2013; 8:e83801. [PMID: 24376752 PMCID: PMC3869817 DOI: 10.1371/journal.pone.0083801] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 11/18/2013] [Indexed: 11/19/2022] Open
Abstract
Obesity is a chronic metabolic disorder caused by imbalance between energy intake and expenditure, and is one of the principal causative factors in the development of metabolic syndrome, diabetes and cancer. COH-SR4 (“SR4”) is a novel investigational compound that has anti-cancer and anti-adipogenic properties. In this study, the effects of SR4 on metabolic alterations in high fat diet (HFD)-induced obese C57BL/J6 mice were investigated. Oral feeding of SR4 (5 mg/kg body weight.) in HFD mice for 6 weeks significantly reduced body weight, prevented hyperlipidemia and improved glycemic control without affecting food intake. These changes were associated with marked decreases in epididymal fat mass, adipocyte hypertrophy, increased plasma adiponectin and reduced leptin levels. SR4 treatment also decreased liver triglycerides, prevented hepatic steatosis, and normalized liver enzymes. Western blots demonstrated increased AMPK activation in liver and adipose tissues of SR4-treated HFD obese mice, while gene analyses by real time PCR showed COH-SR4 significantly suppressed the mRNA expression of lipogenic genes such as sterol regulatory element binding protein-1c (Srebf1), acetyl-Coenzyme A carboxylase (Acaca), peroxisome proliferator-activated receptor gamma (Pparg), fatty acid synthase (Fasn), stearoyl-Coenzyme A desaturase 1 (Scd1), carnitine palmitoyltransferase 1a (Cpt1a) and 3-hydroxy-3-methyl-glutaryl-CoA reductase (Hmgcr), as well as gluconeogenic genes phosphoenolpyruvate carboxykinase 1 (Pck1) and glucose-6-phosphatase (G6pc) in the liver of obese mice. In vitro, SR4 activates AMPK independent of upstream kinases liver kinase B1 (LKB1) and Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ). Together, these data suggest that SR4, a novel AMPK activator, may be a promising therapeutic compound for treatment of obesity, fatty liver disease, and related metabolic disorders.
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Affiliation(s)
- James Lester Figarola
- Departments of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Preeti Singhal
- Departments of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Samuel Rahbar
- Departments of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Bogdan Gabriel Gugiu
- Immunology and Mass Spectrometry and Proteomics Core, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America,
| | - Sanjay Awasthi
- Departments of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
- Medical Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
| | - Sharad S. Singhal
- Departments of Diabetes and Metabolic Diseases Research, Beckman Research Institute, City of Hope National Medical Center, Duarte, California, United States of America
- * E-mail:
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205
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Luu W, Sharpe LJ, Gelissen IC, Brown AJ. The role of signalling in cellular cholesterol homeostasis. IUBMB Life 2013; 65:675-84. [PMID: 23847008 DOI: 10.1002/iub.1182] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 04/21/2013] [Indexed: 12/19/2022]
Abstract
Cholesterol is a vital lipid and performs diverse functions on a whole body and cellular level. However, excess cellular cholesterol is toxic, and thus, elegant mechanisms have evolved to tightly regulate this important lipid. The regulation of cholesterol homeostasis is an area of intense research, and the role that signalling plays is gradually becoming more widely recognised. Cholesterol homeostasis is achieved through intricate mechanisms involving synthesis, uptake, and efflux. Although there is a large body of work elucidating these cholesterol-related pathways, less is known about the role of signalling in these processes. Here, we discuss the variety of ways that signalling impacts on these modes and levels of cholesterol homeostasis, including transcriptional regulation. Most work thus far has investigated the role of kinases in cholesterol efflux (especially on ATP-binding cassette transporter A1, ABCA1), and therefore constitutes a major focus of this review. We also indicate further avenues to explore in the area of signalling in cellular cholesterol homeostasis.
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Affiliation(s)
- Winnie Luu
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, NSW, Australia
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206
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A dihydrochalcone and several homoisoflavonoids from Polygonatum odoratum are activators of adenosine monophosphate-activated protein kinase. Bioorg Med Chem Lett 2013; 23:3137-9. [DOI: 10.1016/j.bmcl.2013.04.027] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 04/03/2013] [Accepted: 04/10/2013] [Indexed: 11/17/2022]
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207
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Filippov S, Pinkosky SL, Lister RJ, Pawloski C, Hanselman JC, Cramer CT, Srivastava RAK, Hurley TR, Bradshaw CD, Spahr MA, Newton RS. ETC-1002 regulates immune response, leukocyte homing, and adipose tissue inflammation via LKB1-dependent activation of macrophage AMPK. J Lipid Res 2013; 54:2095-2108. [PMID: 23709692 DOI: 10.1194/jlr.m035212] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ETC-1002 is an investigational drug currently in Phase 2 development for treatment of dyslipidemia and other cardiometabolic risk factors. In dyslipidemic subjects, ETC-1002 not only reduces plasma LDL cholesterol but also significantly attenuates levels of hsCRP, a clinical biomarker of inflammation. Anti-inflammatory properties of ETC-1002 were further investigated in primary human monocyte-derived macrophages and in in vivo models of inflammation. In cells treated with ETC-1002, increased levels of AMP-activated protein kinase (AMPK) phosphorylation coincided with reduced activity of MAP kinases and decreased production of proinflammatory cytokines and chemokines. AMPK phosphorylation and inhibitory effects of ETC-1002 on soluble mediators of inflammation were significantly abrogated by siRNA-mediated silencing of macrophage liver kinase B1 (LKB1), indicating that ETC-1002 activates AMPK and exerts its anti-inflammatory effects via an LKB1-dependent mechanism. In vivo, ETC-1002 suppressed thioglycollate-induced homing of leukocytes into mouse peritoneal cavity. Similarly, in a mouse model of diet-induced obesity, ETC-1002 restored adipose AMPK activity, reduced JNK phosphorylation, and diminished expression of macrophage-specific marker 4F/80. These data were consistent with decreased epididymal fat-pad mass and interleukin (IL)-6 release by inflamed adipose tissue. Thus, ETC-1002 may provide further clinical benefits for patients with cardiometabolic risk factors by reducing systemic inflammation linked to insulin resistance and vascular complications of metabolic syndrome.
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208
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Yeh CC, Chang SF, Huang TY, Chang HI, Kuo HC, Wu YC, Hsieh CH, Shi CS, Chen CN. Shear stress modulates macrophage-induced urokinase plasminogen activator expression in human chondrocytes. Arthritis Res Ther 2013; 15:R53. [PMID: 23597113 PMCID: PMC4060380 DOI: 10.1186/ar4215] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 04/16/2013] [Indexed: 01/15/2023] Open
Abstract
Introduction Synovial macrophages, which can release proinflammatory factors, are responsible for the upregulation of cartilage-breakdown proteases and play critical roles in cartilage degradation during the progression of osteoarthritis (OA). In addition, shear stress exerts multifunctional effects on chondrocytes by inducing the synthesis of catabolic or anabolic genes. However, the interplay of macrophages, chondrocytes, and shear stress during the regulation of cartilage function remains poorly understood. We investigated the mechanisms underlying the modulation of human chondrocyte urokinase plasminogen activator (uPA) expression by macrophages and shear stress. Methods Human chondrocytes were stimulated by peripheral blood-macrophage- conditioned medium (PB-MCM), or exposure of chondrocytes cultured in PB-MCM to different levels of shear stress (2 to 20 dyn/cm2). Real-time polymerase chain reaction was used to analyze uPA gene expression. Inhibitors and small interfering RNA were used to investigate the mechanism for the effects of PB-MCM and shear stress in chondrocytes. Results Stimulation of human chondrocytes with PB-MCM was found to induce uPA expression. We demonstrated that activation of the JNK and Akt pathways and NF-κB are critical for PB-MCM-induced uPA expression. Blocking assays by using IL-1ra further demonstrated that IL-1β in PB-MCM is the major mediator of uPA expression in chondrocytes. PB-MCM-treated chondrocytes subjected to a lower level of shear stress showed inhibition of MCM-induced JNK and Akt phosphorylation, NF-κB activation, and uPA expression. The PB-MCM-induced uPA expression was suppressed by AMP-activated protein kinase (AMPK) agonist. The inhibitor or siRNA for AMPK abolished the shear-mediated inhibition of uPA expression. Conclusions These data support the hypothesis that uPA upregulation stimulated by macrophages may play an active role in the onset of OA and in the shear-stress protection against this induction.
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209
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Zemel MB, Bruckbauer A. Effects of a leucine and pyridoxine-containing nutraceutical on body weight and composition in obese subjects. Diabetes Metab Syndr Obes 2013; 6:309-15. [PMID: 24003309 PMCID: PMC3755702 DOI: 10.2147/dmso.s49623] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND We recently demonstrated leucine to modulate energy partitioning between adipose tissue and muscle. Further, leucine exhibits a synergy with B6, resulting in reduced adipocyte lipid storage coupled with increased muscle fat oxidation. Accordingly, a nutraceutical (NuShape™) containing 2.25 g leucine and 30 mg B6 increased fat oxidation by >30 g/day in a 28-day randomized controlled trial. The present study evaluated the long-term efficacy of this combination in modulating body weight and composition. METHODS Two 24-week, placebo-controlled, randomized trials, one with weight maintenance (n = 20) and one hypocaloric (-500 kcal/day; n = 24), were conducted using the nutraceutical Nushape in obese subjects. RESULTS The supplement resulted in fat loss in the maintenance study (-1.12 ± 0.36 and -1.82 ± 0.70 kg at 12 and 24 weeks, P < 0.01 versus placebo) while no change was found in the placebo group. In the hypocaloric study, the supplement group lost up to twice as much weight (6.18 ± 1.02 versus 3.40 ± 0.81 kg at 12 weeks and 8.15 ± 1.33 versus 5.25 ± 1.13 kg at 24 weeks, P < 0.01) and fat (4.96 ± 0.61 versus 2.31 ± 0.53 kg at 12 weeks and 7.00 ± 0.95 versus 4.22 ± 0.74 kg at 24 weeks, P < 0.01) than the placebo group. CONCLUSION This nutraceutical combination results in significant fat loss in the absence of caloric restriction and markedly enhances weight and fat loss by 50%-80% over a 24-week period.
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Affiliation(s)
- Michael B Zemel
- NuSirt Sciences, Inc., The University of Tennessee, Knoxville, TN, USA
- Nutrition Department, The University of Tennessee, Knoxville, TN, USA
- Correspondence: Michael B Zemel, NuSirt Sciences, Inc., 11020 Solway School Road, Suite 109, Knoxville, TN 37931, USA, Tel +1 865 206 6154, Email
| | - Antje Bruckbauer
- NuSirt Sciences, Inc., The University of Tennessee, Knoxville, TN, USA
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210
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Bruckbauer A, Zemel MB. Synergistic effects of metformin, resveratrol, and hydroxymethylbutyrate on insulin sensitivity. Diabetes Metab Syndr Obes 2013; 6:93-102. [PMID: 23430507 PMCID: PMC3575126 DOI: 10.2147/dmso.s40840] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The purpose of this study was to determine whether a mixture of the polyphenol, resveratrol, and the leucine metabolite, hydroxymethylbutyrate (HMB), acts synergistically with low doses of metformin to impact insulin sensitivity and AMP-activated protein kinase-dependent outcomes in cell culture and in diabetic mice. METHODS C2C12 skeletal myotubes and 3T3-L1 adipocytes were treated with resveratrol 0.2 μM, HMB 5 μM, and metformin 0.1 mM alone or in combination. db/db mice were treated for 2 weeks with high (1.5 g/kg diet), low (0.75 g/kg diet), or very low (0.25 g/kg diet) doses of metformin alone or in combination with a diet containing resveratrol 12.5 mg and CaHMB 2 g/kg. RESULTS The combination of metformin-resveratrol-HMB significantly increased fat oxidation, AMP-activated protein kinase, and Sirt1 activity in muscle cells compared with metformin or resveratrol-HMB alone. A similar trend was found in 3T3L1 adipocytes. In mice, the two lower doses of metformin exerted no independent effect but, when combined with resveratrol-HMB, both low-dose and very low-dose metformin improved insulin sensitivity (HOMA(IR)), plasma insulin levels, and insulin tolerance test response to a level comparable with that found for high-dose metformin. In addition, the metformin-resveratrol-HMB combination decreased visceral fat and liver weight in mice. CONCLUSION Resveratrol-HMB combined with metformin may act synergistically on AMP-activated protein kinase-dependent pathways, leading to increased insulin sensitivity, which may reduce the therapeutic doses of metformin necessary in the treatment of diabetes.
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Affiliation(s)
| | - Michael B Zemel
- NuSirt Sciences Inc, Knoxville, TN, USA
- Department of Nutrition, University of Tennessee, Knoxville, TN, USA
- Correspondence: Michael B Zemel 11020 Solway School Rd, Knoxville, TN 37931, USA, Tel +1 865 206 6154, Email
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