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Milton-Laskibar I, Aguirre L, Fernández-Quintela A, Rolo AP, Soeiro Teodoro J, Palmeira CM, Portillo MP. Lack of Additive Effects of Resveratrol and Energy Restriction in the Treatment of Hepatic Steatosis in Rats. Nutrients 2017; 9:nu9070737. [PMID: 28696376 PMCID: PMC5537851 DOI: 10.3390/nu9070737] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/03/2017] [Accepted: 07/05/2017] [Indexed: 02/06/2023] Open
Abstract
The aims of the present study were to analyze the effect of resveratrol on liver steatosis in obese rats, to compare the effects induced by resveratrol and energy restriction and to research potential additive effects. Rats were initially fed a high-fat high-sucrose diet for six weeks and then allocated in four experimental groups fed a standard diet: a control group, a resveratrol-treated group, an energy restricted group and a group submitted to energy restriction and treated with resveratrol. We measured liver triacylglycerols, transaminases, FAS, MTP, CPT1a, CS, COX, SDH and ATP synthase activities, FATP2/FATP5, DGAT2, PPARα, SIRT1, UCP2 protein expressions, ACC and AMPK phosphorylation and PGC1α deacetylation. Resveratrol reduced triacylglycerols compared with the controls, although this reduction was lower than that induced by energy restriction. The mechanisms of action were different. Both decreased protein expression of fatty acid transporters, thus suggesting reduced fatty acid uptake from blood stream and liver triacylglycerol delivery, but only energy restriction reduced the assembly. These results show that resveratrol is useful for liver steatosis treatment within a balanced diet, although its effectiveness is lower than that of energy restriction. However, resveratrol is unable to increase the reduction in triacylglycerol content induced by energy restriction.
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Affiliation(s)
- Iñaki Milton-Laskibar
- Nutrition and Obesity Group, Department of Nutrition and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, Facultad de Farmacia, Vitoria 01006, Spain.
- CIBERobn Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, Vitoria 01006, Spain.
| | - Leixuri Aguirre
- Nutrition and Obesity Group, Department of Nutrition and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, Facultad de Farmacia, Vitoria 01006, Spain.
- CIBERobn Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, Vitoria 01006, Spain.
| | - Alfredo Fernández-Quintela
- Nutrition and Obesity Group, Department of Nutrition and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, Facultad de Farmacia, Vitoria 01006, Spain.
- CIBERobn Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, Vitoria 01006, Spain.
| | - Anabela P Rolo
- Department of Life Sciences and Center for Neurosciences and Cell Biology, University of Coimbra, Coimbra 3004-517, Portugal.
| | - João Soeiro Teodoro
- Department of Life Sciences and Center for Neurosciences and Cell Biology, University of Coimbra, Coimbra 3004-517, Portugal.
| | - Carlos M Palmeira
- Department of Life Sciences and Center for Neurosciences and Cell Biology, University of Coimbra, Coimbra 3004-517, Portugal.
| | - María P Portillo
- Nutrition and Obesity Group, Department of Nutrition and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, Facultad de Farmacia, Vitoria 01006, Spain.
- CIBERobn Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, Vitoria 01006, Spain.
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Geisler CE, Renquist BJ. Hepatic lipid accumulation: cause and consequence of dysregulated glucoregulatory hormones. J Endocrinol 2017; 234:R1-R21. [PMID: 28428362 DOI: 10.1530/joe-16-0513] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/20/2017] [Indexed: 12/11/2022]
Abstract
Fatty liver can be diet, endocrine, drug, virus or genetically induced. Independent of cause, hepatic lipid accumulation promotes systemic metabolic dysfunction. By acting as peroxisome proliferator-activated receptor (PPAR) ligands, hepatic non-esterified fatty acids upregulate expression of gluconeogenic, beta-oxidative, lipogenic and ketogenic genes, promoting hyperglycemia, hyperlipidemia and ketosis. The typical hormonal environment in fatty liver disease consists of hyperinsulinemia, hyperglucagonemia, hypercortisolemia, growth hormone deficiency and elevated sympathetic tone. These endocrine and metabolic changes further encourage hepatic steatosis by regulating adipose tissue lipolysis, liver lipid uptake, de novo lipogenesis (DNL), beta-oxidation, ketogenesis and lipid export. Hepatic lipid accumulation may be induced by 4 separate mechanisms: (1) increased hepatic uptake of circulating fatty acids, (2) increased hepatic de novo fatty acid synthesis, (3) decreased hepatic beta-oxidation and (4) decreased hepatic lipid export. This review will discuss the hormonal regulation of each mechanism comparing multiple physiological models of hepatic lipid accumulation. Nonalcoholic fatty liver disease (NAFLD) is typified by increased hepatic lipid uptake, synthesis, oxidation and export. Chronic hepatic lipid signaling through PPARgamma results in gene expression changes that allow concurrent activity of DNL and beta-oxidation. The importance of hepatic steatosis in driving systemic metabolic dysfunction is highlighted by the common endocrine and metabolic disturbances across many conditions that result in fatty liver. Understanding the mechanisms underlying the metabolic dysfunction that develops as a consequence of hepatic lipid accumulation is critical to identifying points of intervention in this increasingly prevalent disease state.
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Affiliation(s)
- Caroline E Geisler
- School of Animal and Comparative Biomedical SciencesUniversity of Arizona, Tucson, Arizona, USA
| | - Benjamin J Renquist
- School of Animal and Comparative Biomedical SciencesUniversity of Arizona, Tucson, Arizona, USA
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53
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Sullivan EM, Fix A, Crouch MJ, Sparagna GC, Zeczycki TN, Brown DA, Shaikh SR. Murine diet-induced obesity remodels cardiac and liver mitochondrial phospholipid acyl chains with differential effects on respiratory enzyme activity. J Nutr Biochem 2017; 45:94-103. [PMID: 28437736 PMCID: PMC5502532 DOI: 10.1016/j.jnutbio.2017.04.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/31/2017] [Accepted: 04/06/2017] [Indexed: 12/23/2022]
Abstract
Cardiac phospholipids, notably cardiolipin, undergo acyl chain remodeling and/or loss of content in aging and cardiovascular diseases, which is postulated to mechanistically impair mitochondrial function. Less is known about how diet-induced obesity influences cardiac phospholipid acyl chain composition and thus mitochondrial responses. Here we first tested if a high fat diet remodeled murine cardiac mitochondrial phospholipid acyl chain composition and consequently disrupted membrane packing, supercomplex formation and respiratory enzyme activity. Mass spectrometry analyses revealed that mice consuming a high fat diet displayed 0.8-3.3 fold changes in cardiac acyl chain remodeling of cardiolipin, phosphatidylcholine, and phosphatidylethanolamine. Biophysical analysis of monolayers constructed from mitochondrial phospholipids of obese mice showed impairment in the packing properties of the membrane compared to lean mice. However, the high fat diet, relative to the lean controls, had no influence on cardiac mitochondrial supercomplex formation, respiratory enzyme activity, and even respiration. To determine if the effects were tissue specific, we subsequently conducted select studies with liver tissue. Compared to the control diet, the high fat diet remodeled liver mitochondrial phospholipid acyl chain composition by 0.6-5.3-fold with notable increases in n-6 and n-3 polyunsaturation. The remodeling in the liver was accompanied by diminished complex I to III respiratory enzyme activity by 3.5-fold. Finally, qRT-PCR analyses demonstrated an upregulation of liver mRNA levels of tafazzin, which contributes to cardiolipin remodeling. Altogether, these results demonstrate that diet-induced obesity remodels acyl chains in the mitochondrial phospholipidome and exerts tissue specific impairments of respiratory enzyme activity.
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Affiliation(s)
- E Madison Sullivan
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA; East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA
| | - Amy Fix
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA; East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA
| | - Miranda J Crouch
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA; East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA
| | - Genevieve C Sparagna
- Department of Medicine, Division of Cardiology, University of Colorado Denver Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Tonya N Zeczycki
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA; East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA
| | - David A Brown
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech Corporate Research Center, 1981 Kraft Drive, Blacksburg, VA 24060, USA
| | - Saame Raza Shaikh
- Department of Biochemistry & Molecular Biology, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA; East Carolina Diabetes & Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, NC 27834, USA.
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Buron N, Porceddu M, Roussel C, Begriche K, Trak-Smayra V, Gicquel T, Fromenty B, Borgne-Sanchez A. Chronic and low exposure to a pharmaceutical cocktail induces mitochondrial dysfunction in liver and hyperglycemia: Differential responses between lean and obese mice. ENVIRONMENTAL TOXICOLOGY 2017; 32:1375-1389. [PMID: 27501252 DOI: 10.1002/tox.22331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 07/07/2016] [Accepted: 07/17/2016] [Indexed: 06/06/2023]
Abstract
Pharmaceuticals are found in the environment but the impact of this contamination on human and animal health is poorly known. The liver could be particularly targeted since a significant number of these drugs are hepatotoxic, in particular via oxidative stress and mitochondrial dysfunction. Notably, the latter events can also be observed in liver diseases linked to obesity, so that the obese liver might be more sensitive to drug toxicity. In this study, we determined the effects of a chronic exposure to low doses of pharmaceuticals in wild-type and obese mice, with a particular focus on mitochondrial function. To this end, wild-type and ob/ob mice were exposed for 4 months to a cocktail of 11 pharmaceuticals provided in drinking water containing 0.01, 0.1, or 1 mg/L of each drug. At the end of the treatment, liver mitochondria were isolated and different parameters were measured. Chronic exposure to the pharmaceuticals reduced mitochondrial respiration driven by succinate and palmitoyl-l-carnitine in wild-type mice and increased antimycin-induced ROS production in ob/ob mice. Hyperglycemia and hepatic histological abnormalities were also observed in treated ob/ob mice. Investigations were also carried out in isolated liver mitochondria incubated with the mixture, or with each individual drug. The mitochondrial effects of the mixture were different from those observed in treated mice and could not be predicted from the results obtained with each drug. Because some of the 11 drugs included in our cocktail can be found in water at relatively high concentrations, our data could be relevant in environmental toxicology. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1375-1389, 2017.
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Affiliation(s)
- Nelly Buron
- MITOLOGICS S.A.S. Hôpital Robert Debré, 48 Bd Sérurier, 75019, Paris, France
| | - Mathieu Porceddu
- MITOLOGICS S.A.S. Hôpital Robert Debré, 48 Bd Sérurier, 75019, Paris, France
| | - Célestin Roussel
- MITOLOGICS S.A.S. Hôpital Robert Debré, 48 Bd Sérurier, 75019, Paris, France
| | - Karima Begriche
- Faculté De Pharmacie, INSERM, U991, 2 Av Du Prof. Léon Bernard, 35043, Rennes, France
| | | | - Thomas Gicquel
- Faculté De Pharmacie, INSERM, U991, 2 Av Du Prof. Léon Bernard, 35043, Rennes, France
- CHU Pontchaillou, Laboratoire De Toxicologie Biologique Et Médico-Légale, 35033, Rennes, France
| | - Bernard Fromenty
- Faculté De Pharmacie, INSERM, U991, 2 Av Du Prof. Léon Bernard, 35043, Rennes, France
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55
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Jin X, Liu J, Chen YP, Xiang Z, Ding JX, Li YM. Effect of miR-146 targeted HDMCP up-regulation in the pathogenesis of nonalcoholic steatohepatitis. PLoS One 2017; 12:e0174218. [PMID: 28346483 PMCID: PMC5367781 DOI: 10.1371/journal.pone.0174218] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 03/05/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUNDS/AIMS Mitochondrial dysfunction plays an important role inthe pathogenesis of nonalcoholic steatohepatitis (NASH), where uncoupling protein (UCP) is actively involved. We previously reported the uncoupling activity of HDMCP and its role in liver steatosis. We now aim to investigate the degree and therapeutic effect of HDMCP in NASH and the regulatory role of miR-146 on HDMCP. METHODS NASH animal model was established by feeding BALB/c mice with MCD diet while L02 cell was cultured with high concentration of fatty acid (HFFA) for 72h to mimic the steatosis and inflammation of NASH in-vitro appearance. The steatosis level was assessed by H-E/oil-red staining and serum/supernatant marker detection. The inflammation activity was evaluated by levels of Hepatic activity index, transwell, apoptosis degree (TUNEL/flow cytometry) and serum/supernatant marker. HDMCP level was detected by western blot and miRNA expression was tested by qRT-PCR. NASH severity change was recorded after RNA interference while the regulatory role of miR-146 on HDMCP was confirmed by dual luciferase report system. The H2O2 and ATP levels were measured for mechanism exploration. RESULTS Increased HDMCP expression was identified in NASH animal model and HFFA-72h cultured L02 cell. Moreover, under regulation of miR-146, NASH alleviation was achieved after HDMCP downregulation in both in vivo and in vitro, according to the declination of steatosis and inflammation related markers. Though H2O2 and ATP levels were increased and decreased in NASH models, HDMCP down regulation both increased their levels. CONCLUSIONS The miR-146-HDMCP-ATP/H2O2 pathway may provide novel mechanism and treatment option for NASH.
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Affiliation(s)
- Xi Jin
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
- * E-mail:
| | - Jiang Liu
- Department of Gastroenterology, Huzhou Central Hospital, Huzhou, China
| | - Yi-peng Chen
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Zun Xiang
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
| | - Jie-xia Ding
- Department of infectious disease, Hangzhou first people's hospital, Hangzhou, China
| | - You-ming Li
- Department of Gastroenterology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
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Kanuri BN, Kanshana JS, Rebello SC, Pathak P, Gupta AP, Gayen JR, Jagavelu K, Dikshit M. Altered glucose and lipid homeostasis in liver and adipose tissue pre-dispose inducible NOS knockout mice to insulin resistance. Sci Rep 2017; 7:41009. [PMID: 28106120 PMCID: PMC5247703 DOI: 10.1038/srep41009] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 12/14/2016] [Indexed: 12/15/2022] Open
Abstract
On the basis of diet induced obesity and KO mice models, nitric oxide is implied to play an important role in the initiation of dyslipidemia induced insulin resistance. However, outcomes using iNOS KO mice have so far remained inconclusive. The present study aimed to assess IR in iNOS KO mice after 5 weeks of LFD feeding by monitoring body composition, energy homeostasis, insulin sensitivity/signaling, nitrite content and gene expressions changes in the tissues. We found that body weight and fat content in KO mice were significantly higher while the respiratory exchange ratio (RER), volume of carbon dioxide (VCO2), and heat production were lower as compared to WT mice. Furthermore, altered systemic glucose tolerance, tissue insulin signaling, hepatic gluconeogenesis, augmented hepatic lipids, adiposity, as well as gene expression regulating lipid synthesis, catabolism and efflux were evident in iNOS KO mice. Significant reduction in eNOS and nNOS gene expression, hepatic and adipose tissue nitrite content, circulatory nitrite was also observed. Oxygen consumption rate of mitochondrial respiration has remained unaltered in KO mice as measured using extracellular flux analyzer. Our findings establish a link between the NO status with systemic and tissue specific IR in iNOS KO mice at 5 weeks.
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Affiliation(s)
- Babu Nageswararao Kanuri
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India.,Academy of Scientific and Innovative Research, New Delhi - 110001, India
| | - Jitendra S Kanshana
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Sanjay C Rebello
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Priya Pathak
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Anand P Gupta
- Pharmacokinetics and Metabolism Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Jiaur R Gayen
- Pharmacokinetics and Metabolism Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Kumaravelu Jagavelu
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow - 226031, India
| | - Madhu Dikshit
- Academy of Scientific and Innovative Research, New Delhi - 110001, India
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Zingg JM, Hasan ST, Nakagawa K, Canepa E, Ricciarelli R, Villacorta L, Azzi A, Meydani M. Modulation of cAMP levels by high-fat diet and curcumin and regulatory effects on CD36/FAT scavenger receptor/fatty acids transporter gene expression. Biofactors 2017; 43:42-53. [PMID: 27355903 DOI: 10.1002/biof.1307] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 05/24/2016] [Accepted: 06/03/2016] [Indexed: 02/06/2023]
Abstract
Curcumin, a polyphenol from turmeric (Curcuma longa), reduces inflammation, atherosclerosis, and obesity in several animal studies. In Ldlr-/- mice fed a high-fat diet (HFD), curcumin reduces plasma lipid levels, therefore contributing to a lower accumulation of lipids and to reduced expression of fatty acid transport proteins (CD36/FAT, FABP4/aP2) in peritoneal macrophages. In this study, we analyzed the molecular mechanisms by which curcumin (500, 1000, 1500 mg/kg diet, for 4 months) may influence plasma and tissue lipid levels in Ldlr-/- mice fed an HFD. In liver, HFD significantly suppressed cAMP levels, and curcumin restored almost normal levels. Similar trends were observed in adipose tissues, but not in brain, skeletal muscle, spleen, and kidney. Treatment with curcumin increased phosphorylation of CREB in liver, what may play a role in regulatory effects of curcumin in lipid homeostasis. In cell lines, curcumin increased the level of cAMP, activated the transcription factor CREB and the human CD36 promoter via a sequence containing a consensus CREB response element. Regulatory effects of HFD and Cur on gene expression were observed in liver, less in skeletal muscle and not in brain. Since the cAMP/protein kinase A (PKA)/CREB pathway plays an important role in lipid homeostasis, energy expenditure, and thermogenesis by increasing lipolysis and fatty acid β-oxidation, an increase in cAMP levels induced by curcumin may contribute to its hypolipidemic and anti-atherosclerotic effects. © 2016 BioFactors, 43(1):42-53, 2017.
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Affiliation(s)
- Jean-Marc Zingg
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Syeda T Hasan
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Kiyotaka Nakagawa
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Elisa Canepa
- Department of Experimental Medicine, Section of General Pathology, University of Genoa, Genoa, Italy
| | - Roberta Ricciarelli
- Department of Experimental Medicine, Section of General Pathology, University of Genoa, Genoa, Italy
| | - Luis Villacorta
- Cardiovascular Center, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, MI, USA
| | - Angelo Azzi
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
| | - Mohsen Meydani
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, 02111, USA
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Iannucci LF, Sun J, Singh BK, Zhou J, Kaddai VA, Lanni A, Yen PM, Sinha RA. Short chain fatty acids induce UCP2-mediated autophagy in hepatic cells. Biochem Biophys Res Commun 2016; 480:461-467. [PMID: 27773823 DOI: 10.1016/j.bbrc.2016.10.072] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 10/19/2016] [Indexed: 02/07/2023]
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Geisler CE, Hepler C, Higgins MR, Renquist BJ. Hepatic adaptations to maintain metabolic homeostasis in response to fasting and refeeding in mice. Nutr Metab (Lond) 2016; 13:62. [PMID: 27708682 PMCID: PMC5037643 DOI: 10.1186/s12986-016-0122-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 09/15/2016] [Indexed: 12/26/2022] Open
Abstract
Background The increased incidence of obesity and associated metabolic diseases has driven research focused on genetically or pharmacologically alleviating metabolic dysfunction. These studies employ a range of fasting-refeeding models including 4–24 h fasts, “overnight” fasts, or meal feeding. Still, we lack literature that describes the physiologically relevant adaptations that accompany changes in the duration of fasting and re-feeding. Since the liver is central to whole body metabolic homeostasis, we investigated the timing of the fast-induced shift toward glycogenolysis, gluconeogenesis, and ketogenesis and the meal-induced switch toward glycogenesis and away from ketogenesis. Methods Twelve to fourteen week old male C57BL/6J mice were fasted for 0, 4, 8, 12, or 16 h and sacrificed 4 h after lights on. In a second study, designed to understand the response to a meal, we gave fasted mice access to feed for 1 or 2 h before sacrifice. We analyzed the data using mixed model analysis of variance. Results Fasting initiated robust metabolic shifts, evidenced by changes in serum glucose, non-esterified fatty acids (NEFAs), triacylglycerol, and β-OH butyrate, as well as, liver triacylglycerol, non-esterified fatty acid, and glycogen content. Glycogenolysis is the primary source to maintain serum glucose during the first 8 h of fasting, while de novo gluconeogenesis is the primary source thereafter. The increase in serum β-OH butyrate results from increased enzymatic capacity for fatty acid flux through β-oxidation and shunting of acetyl-CoA toward ketone body synthesis (increased CPT1 (Carnitine Palmitoyltransferase 1) and HMGCS2 (3-Hydroxy-3-Methylglutaryl-CoA Synthase 2) expression, respectively). In opposition to the relatively slow metabolic adaptation to fasting, feeding of a meal results in rapid metabolic changes including full depression of serum β-OH butyrate and NEFAs within an hour. Conclusions Herein, we provide a detailed description of timing of the metabolic adaptations in response to fasting and re-feeding to inform study design in experiments of metabolic homeostasis. Since fasting and obesity are both characterized by elevated adipose tissue lipolysis, hepatic lipid accumulation, ketogenesis, and gluconeogenesis, understanding the drivers behind the metabolic shift from the fasted to the fed state may provide targets to limit aberrant gluconeogenesis and ketogenesis in obesity.
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Affiliation(s)
- C E Geisler
- School of Animal and Comparative Biomedical Sciences, University of Arizona, 4101 North Campbell Avenue, Tucson, AZ 85719 USA
| | - C Hepler
- School of Animal and Comparative Biomedical Sciences, University of Arizona, 4101 North Campbell Avenue, Tucson, AZ 85719 USA.,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75235 USA
| | - M R Higgins
- School of Animal and Comparative Biomedical Sciences, University of Arizona, 4101 North Campbell Avenue, Tucson, AZ 85719 USA
| | - B J Renquist
- School of Animal and Comparative Biomedical Sciences, University of Arizona, 4101 North Campbell Avenue, Tucson, AZ 85719 USA
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Esteban-Zubero E, García-Gil FA, López-Pingarrón L, Alatorre-Jiménez MA, Ramírez JM, Tan DX, García JJ, Reiter RJ. Melatonin role preventing steatohepatitis and improving liver transplantation results. Cell Mol Life Sci 2016; 73:2911-27. [PMID: 27022943 PMCID: PMC11108472 DOI: 10.1007/s00018-016-2185-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 03/18/2016] [Indexed: 12/18/2022]
Abstract
Liver steatosis is a prevalent process that is induced due to alcoholic or non-alcoholic intake. During the course of these diseases, the generation of reactive oxygen species, followed by molecular damage to lipids, protein and DMA occurs generating organ cell death. Transplantation is the last-resort treatment for the end stage of both acute and chronic hepatic diseases, but its success depends on ability to control ischemia-reperfusion injury, preservation fluids used, and graft quality. Melatonin is a powerful endogenous antioxidant produced by the pineal gland and a variety of other because of its efficacy in organs; melatonin has been investigated to improve the outcome of organ transplantation by reducing ischemia-reperfusion injury and due to its synergic effect with organ preservation fluids. Moreover, this indolamine also prevent liver steatosis. That is important because this disease may evolve leading to an organ transplantation. This review summarizes the observations related to melatonin beneficial actions in organ transplantation and ischemic-reperfusion models.
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Affiliation(s)
- Eduardo Esteban-Zubero
- Department of Pharmacology and Physiology, University of Zaragoza, Calle Domingo Miral s/n, 50009, Saragossa, Spain.
| | - Francisco Agustín García-Gil
- Department of Surgery, Gynaecology and Obstetrics, University of Zaragoza, Calle Domingo Miral s/n, 50009, Saragossa, Spain
| | - Laura López-Pingarrón
- Department of Medicine, Psychiatry and Dermatology, University of Zaragoza, Calle Domingo Miral s/n, 50009, Saragossa, Spain
| | - Moisés Alejandro Alatorre-Jiménez
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - José Manuel Ramírez
- Department of Surgery, Gynaecology and Obstetrics, University of Zaragoza, Calle Domingo Miral s/n, 50009, Saragossa, Spain
| | - Dun-Xian Tan
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA
| | - José Joaquín García
- Department of Pharmacology and Physiology, University of Zaragoza, Calle Domingo Miral s/n, 50009, Saragossa, Spain
| | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX, 78229, USA.
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Bar-Lev Y, Moshitch-Moshkovitz S, Tsarfaty G, Kaufman D, Horev J, Resau JH, Tsarfaty I. Mimp/Mtch2, an Obesity Susceptibility Gene, Induces Alteration of Fatty Acid Metabolism in Transgenic Mice. PLoS One 2016; 11:e0157850. [PMID: 27359329 PMCID: PMC4928869 DOI: 10.1371/journal.pone.0157850] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 06/06/2016] [Indexed: 12/26/2022] Open
Abstract
Objective Metabolic dysfunctions, such as fatty liver, obesity and insulin resistance, are among the most common contemporary diseases worldwide, and their prevalence is continuously rising. Mimp/Mtch2 is a mitochondrial carrier protein homologue, which localizes to the mitochondria and induces mitochondrial depolarization. Mimp/Mtch2 single-nucleotide polymorphism is associated with obesity in humans and its loss in mice muscle protects from obesity. Our aim was to study the effects of Mimp/Mtch2 overexpression in vivo. Methods Transgenic mice overexpressing Mimp/Mtch2-GFP were characterized and monitored for lipid accumulation, weight and blood glucose levels. Transgenic mice liver and kidneys were used for gene expression analysis. Results Mimp/Mtch2-GFP transgenic mice express high levels of fatty acid synthase and of β-oxidation genes and develop fatty livers and kidneys. Moreover, high-fat diet–fed Mimp/Mtch2 mice exhibit high blood glucose levels. Our results also show that Mimp/Mtch2 is involved in lipid accumulation and uptake in cells and perhaps in human obesity. Conclusions Mimp/Mtch2 alters lipid metabolism and may play a role in the onset of obesity and development of insulin resistance.
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Affiliation(s)
- Yamit Bar-Lev
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | - Galia Tsarfaty
- Department of Diagnostic Imaging, Sheba Medical Center, Ramat-Gan, Israel
| | - Dafna Kaufman
- Van Andel Research Institute, Grand Rapids, Michigan, 49503, United States of America
| | - Judith Horev
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - James H. Resau
- Van Andel Research Institute, Grand Rapids, Michigan, 49503, United States of America
| | - Ilan Tsarfaty
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
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Machado MV, Diehl AM. Pathogenesis of Nonalcoholic Steatohepatitis. Gastroenterology 2016; 150:1769-77. [PMID: 26928243 PMCID: PMC4887389 DOI: 10.1053/j.gastro.2016.02.066] [Citation(s) in RCA: 330] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 01/30/2016] [Accepted: 02/18/2016] [Indexed: 02/08/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is a necro-inflammatory response that ensues when hepatocytes are injured by lipids (lipotoxicity). NASH is a potential outcome of nonalcoholic fatty liver (NAFL), a condition that occurs when lipids accumulate in hepatocytes. NASH may be reversible, but it can also result in cirrhosis and primary liver cancer. We are beginning to learn about the mechanisms of progression of NAFL and NASH. NAFL does not inevitably lead to NASH because NAFL is a heterogeneous condition. This heterogeneity exists because different types of lipids with different cytotoxic potential accumulate in the NAFL, and individuals with NAFL differ in their ability to defend against lipotoxicity. There are no tests that reliably predict which patients with NAFL will develop lipotoxicity. However, NASH encompasses the spectrum of wound-healing responses induced by lipotoxic hepatocytes. Differences in these wound-healing responses among individuals determine whether lipotoxic livers regenerate, leading to stabilization or resolution of NASH, or develop progressive scarring, cirrhosis, and possibly liver cancer. We review concepts that are central to the pathogenesis of NASH.
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Affiliation(s)
- Mariana Verdelho Machado
- Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA,Gastroenterology Department, Hospital de Santa Maria, CHLN, Lisbon, Portugal
| | - Anna Mae Diehl
- Division of Gastroenterology, Department of Medicine, Duke University Medical Center, Durham, North Carolina.
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Trebicka J, Schierwagen R. Hepatic mitochondrial dysfunction in nonalcoholic steatohepatitis: Read-out or reason? Hepatology 2016; 63:1729-32. [PMID: 26845516 DOI: 10.1002/hep.28482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jonel Trebicka
- Department of Internal Medicine I, University of Bonn, Bonn, Germany.,Department of Hepatology, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Robert Schierwagen
- Department of Hepatology, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
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Ramadori P, Drescher H, Erschfeld S, Schumacher F, Berger C, Fragoulis A, Schenkel J, Kensler TW, Wruck CJ, Trautwein C, Kroy DC, Streetz KL. Hepatocyte-specific Keap1 deletion reduces liver steatosis but not inflammation during non-alcoholic steatohepatitis development. Free Radic Biol Med 2016; 91:114-26. [PMID: 26698665 DOI: 10.1016/j.freeradbiomed.2015.12.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/27/2015] [Accepted: 12/12/2015] [Indexed: 01/06/2023]
Abstract
Generation of reactive oxygen species (ROS) in response to fatty acids accumulation has been classically proposed as a possible "second hit" triggering progression from simple steatosis to non-alcoholic steatohepatitis (NASH). In this study we challenged hepatocyte-specific Keap1 knockout mice (Keap1(Δhepa)) and littermate Cre- controls (Keap1(fx/fx)) with two different diet models of NASH in order to evaluate the effects of the anti-oxidant transcription factor Nrf2 over-activation on hepatic metabolism and disease progression. After 4 weeks of MCD diet the liver/body weight ratio of Keap1(Δhepa) mice was significantly higher compared to littermate controls with no differences in total body weight. Strikingly, liver histology revealed a dramatic reduction of lipid droplets confirmed by a decreased content of intra-hepatic triglycerides in Keap1(Δhepa) compared to controls. In parallel to reduced expression of genes involved in lipid droplet formation, protein expression of Liver X Receptor (LXRα/β) and Peroxisome proliferator-activated receptor α (PPARα) was significantly decreased. In contrast, genes involved in mitochondrial lipid catabolism were markedly up-regulated in Keap1(Δhepa) livers. A similar phenotype characterized by inhibition of lipogenesis in favor of increased mitochondrial catabolic activity was also observed after 13 weeks of western diet administration. MCD-induced apoptosis was significantly dampened in Keap1(Δhepa) compared to Keap1(fx/fx) as detected by TUNEL, cleaved caspase-3 and Bcl-2 protein expression analyses. However, no differences in inflammatory F4/80- and CD11b-positive cells and pro-fibrogenic genes were detected between the two groups. Although hepatic lack of Keap1 did not ameliorate inflammation, the resulting constitutive Nrf2 over-activation in hepatocytes strongly reduced hepatic steatosis via enhanced lipid catabolism and repressed de novo lipogenesis during murine NASH development.
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Affiliation(s)
- Pierluigi Ramadori
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany.
| | - Hannah Drescher
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Stephanie Erschfeld
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Fabienne Schumacher
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Cordula Berger
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Athanassios Fragoulis
- Institute of Anatomy and Cell Biology, RWTH Aachen University Hospital, Aachen, Germany
| | - Julia Schenkel
- Institute of Anatomy and Cell Biology, RWTH Aachen University Hospital, Aachen, Germany
| | - Thomas W Kensler
- Department of Pharmacology & Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Christoph J Wruck
- Institute of Anatomy and Cell Biology, RWTH Aachen University Hospital, Aachen, Germany
| | - Christian Trautwein
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Daniela C Kroy
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany
| | - Konrad L Streetz
- Department of Medicine III, RWTH Aachen University Hospital, Aachen, Germany.
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Hirako S, Wakayama Y, Kim H, Iizuka Y, Matsumoto A, Wada N, Kimura A, Okabe M, Sakagami J, Suzuki M, Takenoya F, Shioda S. The relationship between aquaglyceroporin expression and development of fatty liver in diet-induced obesity and ob/ob mice. Obes Res Clin Pract 2015; 10:710-718. [PMID: 26747210 DOI: 10.1016/j.orcp.2015.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 11/24/2015] [Accepted: 12/04/2015] [Indexed: 12/28/2022]
Abstract
Aquaporin (AQP) 7 and AQP9 are subcategorised as aquaglyceroporins which transport glycerin in addition to water. These AQPs may play a role in the homeostasis of energy metabolism. We examined the effect of AQP7, AQP9, and lipid metabolism-related gene expression in obese mice. In diet-induced obese (DIO) mice, excess lipid accumulated in the liver, which was hyperleptinemic and hyperinsulinemic. Hepatic AQP9 gene expression was significantly increased in both DIO and ob/ob mice compared to controls. The mRNA expression levels of fatty acid and triglyceride synthesis-related genes and fatty acid β oxidation-related genes in the liver were also higher in both mouse models, suggesting that triglyceride synthesis in this organ is promoted as a result of glycerol release from adipocytes. Adipose AQP7 and AQP9 gene expressions were increased in DIO mice, but there was no difference in ob/ob mice compared to wild-type mice. In summary, adipose AQP7 and AQP9 gene expressions are increased by diet-induced obesity, indicating that this is one of the mechanisms by which lipid accumulates in response to a high fat diet, not the genetic mutation of ob/ob mice. Hepatic AQP9 gene expression was increased in both obesity model mice. AQP7 and AQP9 therefore have the potential of defining molecules for the characterisation of obesity or fatty liver and may be a target molecules for the treatment of those disease.
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Affiliation(s)
- Satoshi Hirako
- Department of Health and Nutrition, University of Human Arts and Sciences, Saitama, Japan
| | - Yoshihiro Wakayama
- Department of Anatomy, Showa University School of Medicine, Tokyo, Japan; Wakayama Clinic, Machida-shi, Tokyo, Japan
| | - Hyounju Kim
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Yuzuru Iizuka
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Akiyo Matsumoto
- Department of Clinical Dietetics & Human Nutrition, Faculty of Pharmaceutical Sciences, Josai University, Saitama, Japan
| | - Nobuhiro Wada
- Department of Internal Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Ai Kimura
- Hoshi University School of Pharmacy and Pharmaceutical Sciences Global Research Center for Innovative Life Science Peptide Drug Innovation, Tokyo, Japan
| | - Mai Okabe
- Tokyo Shokuryo Dietitian Academy, Tokyo, Japan
| | - Junichi Sakagami
- Department of Anatomy, Showa University School of Medicine, Tokyo, Japan
| | - Mamiko Suzuki
- Department of Biochemistry, Showa University School of Medicine, Tokyo, Japan
| | - Fumiko Takenoya
- Department of Exercise and Sports Physiology, Hoshi University School of Pharmacy and Pharmaceutical Science, Tokyo, Japan
| | - Seiji Shioda
- Hoshi University School of Pharmacy and Pharmaceutical Sciences Global Research Center for Innovative Life Science Peptide Drug Innovation, Tokyo, Japan.
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Cui MH, Jayalakshmi K, Liu L, Guha C, Branch CA. In vivo (1)H MRS and (31)P MRSI of the response to cyclocreatine in transgenic mouse liver expressing creatine kinase. NMR IN BIOMEDICINE 2015; 28:1634-1644. [PMID: 26451872 DOI: 10.1002/nbm.3391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 08/05/2015] [Accepted: 08/11/2015] [Indexed: 06/05/2023]
Abstract
Hepatocyte transplantation has been explored as a therapeutic alternative to liver transplantation, but a means to monitor the success of the procedure is lacking. Published findings support the use of in vivo (31)P MRSI of creatine kinase (CK)-expressing hepatocytes to monitor proliferation of implanted hepatocytes. Phosphocreatine tissue level depends upon creatine (Cr) input to the CK enzyme reaction, but Cr measurement by (1)H MRS suffers from low signal-to-noise ratio (SNR). We examine the possibility of using the Cr analog cyclocreatine (CCr, a substrate for CK), which is quickly phosphorylated to phosphocyclocreatine (PCCr), as a higher SNR alternative to Cr. (1)H MRS and (31)P MRSI were employed to measure the effect of incremental supplementation of CCr upon PCCr, γ-ATP, pH and Pi /ATP in the liver of transgenic mice expressing the BB isoform of CK (CKBB) in hepatocytes. Water supplementation with 0.1% CCr led to a peak total PCCr level of 17.15 ± 1.07 mmol/kg wet weight by 6 weeks, while adding 1.0% CCr led to a stable PCCr liver level of 18.12 ± 3.91 mmol/kg by the fourth day of feeding. PCCr was positively correlated with CCr, and ATP concentration and pH declined with increasing PCCr. Feeding with 1% CCr in water induced an apparent saturated level of PCCr, suggesting that CCr quantization may not be necessary for quantifying expression of CK in mice. These findings support the possibility of using (31)P MRS to noninvasively monitor hepatocyte transplant success with CK-expressing hepatocytes.
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Affiliation(s)
- Min-Hui Cui
- Gruss Magnetic Resonance Research Center, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Kamaiah Jayalakshmi
- Gruss Magnetic Resonance Research Center, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Laibin Liu
- Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Chandan Guha
- Department of Radiation Oncology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Craig A Branch
- Gruss Magnetic Resonance Research Center, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Physiology and Biophysics, Albert Einstein College of Medicine, Bronx, NY, USA
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67
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Vimaleswaran KS, Cavadino A, Verweij N, Nolte IM, Mateo Leach I, Auvinen J, Veijola J, Elliott P, Penninx BW, Snieder H, Järvelin MR, van der Harst P, Cohen RD, Boucher BJ, Hyppönen E. Interactions between uncoupling protein 2 gene polymorphisms, obesity and alcohol intake on liver function: a large meta-analysed population-based study. Eur J Endocrinol 2015; 173:863-72. [PMID: 26526553 DOI: 10.1530/eje-15-0839] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND AND OBJECTIVE Given the role of uncoupling protein 2 (UCP2) in the accumulation of fat in the hepatocytes and in the enhancement of protective mechanisms in acute ethanol intake, we hypothesised that UCP2 polymorphisms are likely to cause liver disease through their interactions with obesity and alcohol intake. To test this hypothesis, we investigated the interaction between tagging polymorphisms in the UCP2 gene (rs2306819, rs599277 and rs659366), alcohol intake and obesity traits such as BMI and waist circumference (WC) on alanine aminotransferase (ALT) and gamma glutamyl transferase (GGT) in a large meta-analysis of data sets from three populations (n=20 242). DESIGN AND METHODS The study populations included the Northern Finland Birth Cohort 1966 (n=4996), Netherlands Study of Depression and Anxiety (n=1883) and LifeLines Cohort Study (n=13 363). Interactions between the polymorphisms and obesity and alcohol intake on dichotomised ALT and GGT levels were assessed using logistic regression and the likelihood ratio test. RESULTS In the meta-analysis of the three cohorts, none of the three UCP2 polymorphisms were associated with GGT or ALT levels. There was no evidence for interaction between the polymorphisms and alcohol intake on GGT and ALT levels. In contrast, the association of WC and BMI with GGT levels varied by rs659366 genotype (Pinteraction=0.03 and 0.007, respectively; adjusted for age, gender, high alcohol intake, diabetes, hypertension and serum lipid concentrations). CONCLUSION In conclusion, our findings in 20 242 individuals suggest that UCP2 gene polymorphisms may cause liver dysfunction through the interaction with body fat rather than alcohol intake.
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Affiliation(s)
- Karani S Vimaleswaran
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Alana Cavadino
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Niek Verweij
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Ilja M Nolte
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Irene Mateo Leach
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Juha Auvinen
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Juha Veijola
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Paul Elliott
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Brenda W Penninx
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Harold Snieder
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Marjo-Riitta Järvelin
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Pim van der Harst
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
| | - Robert D Cohen
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Barbara J Boucher
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia
| | - Elina Hyppönen
- Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Reading RG6 6AP, UKPopulationPolicy and Practice, UCL Institute of Child Health, London, UKWolfson Institute of Preventive MedicineCentre for Environmental and Preventive Medicine, Queen Mary University of London, London, UK, Departments of CardiologyEpidemiologyUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsUnit of Primary CareOulu University Hospital, Oulu, FinlandFaculty of MedicineCenter for Life Course EpidemiologyDepartment of PsychiatryCenter for Clinical Neuroscience, University of Oulu, Oulu, FinlandDepartment of PsychiatryMedical Research Center, University Hospital of Oulu, Oulu, FinlandDepartment of Epidemiology and BiostatisticsImperial College London, MRC-PHE Centre for Environment and Health, London, UKDepartment of PsychiatryLeiden University Medical Center, Leiden, The NetherlandsDepartment of PsychiatryEMGO Institute of Health and Care Research, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The NetherlandsBiocenter OuluUniversity of Oulu, Oulu, FinlandDepartment of GeneticsUniversity Medical Center Groningen, University of Groningen, Groningen, The NetherlandsICIN - Netherlands Heart InstituteDurrer Center for Cardiogenetic Research, Utrecht, The NetherlandsBarts and The London School of Medicine and DentistryQueen Mary University of London, Blizard Institute, Newark Street, London, UKCentre for Population Health ResearchSchool of Health Science and Sansom Institute of Health Research, University of South Australia, Adelaide, South Australia, AustraliaSouth Australian Health and Medical Research InstituteAdelaide, South Australia, Australia Hugh Sinclair Unit of Human NutritionDepartment of Food and Nutritional Sciences, School of Chemistry, Food and Pharmacy, University of Reading, Whiteknights, PO Box 226, Readin
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Pheiffer C, Jacobs C, Patel O, Ghoor S, Muller C, Louw J. Expression of UCP2 in Wistar rats varies according to age and the severity of obesity. J Physiol Biochem 2015; 72:25-32. [PMID: 26621256 DOI: 10.1007/s13105-015-0454-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 11/24/2015] [Indexed: 01/26/2023]
Abstract
Obesity, a complex metabolic disorder, is characterized by mitochondrial dysfunction and oxidative stress. Increased expression of uncoupling protein 2 (UCP2) during obesity is an adaptive response to suppress the production of reactive oxygen species. The aims of this study were to compare the expression of UCP2 in diet-induced obese Wistar rats that differed according to age and their severity of obesity, and to compare UCP2 expression in the liver and muscle of these rats. UCP2 messenger RNA and protein expression was increased 4.6-fold (p < 0.0001) and 3.0-fold (p < 0.05), respectively, in the liver of the older and heavier rats. In contrast, UCP2 expression was decreased twofold (p < 0.005) in the muscle of these rats, while UCP3 messenger RNA (mRNA) was increased twofold (p < 0.01). Peroxisome proliferator-activated receptor alpha (PPARα) was similarly increased (3.0-fold, p < 0.05) in the liver of the older and more severe obese rats. Total protein content was increased (2.3-fold, p < 0.0001), while 5' adenosine monophosphate-activated protein kinase (AMPK) activity was decreased (1.3-fold, p = 0.05) in the liver of the older, heavier rats. No difference in total protein content and AMPK expression was observed in the muscle of these rats. This study showed that the expression of UCP2 varies according to age and the severity of obesity and supports the widely held notion that increased UCP2 expression is an adaptive response to increased fatty acid β-oxidation and reactive oxygen species production that occurs during obesity. An understanding of metabolic adaptation is imperative to gain insight into the underlying causes of disease, thus facilitating intervention strategies to combat disease progression.
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Affiliation(s)
- Carmen Pheiffer
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa.
| | - Carvern Jacobs
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa
| | - Oelfah Patel
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa
| | - Samira Ghoor
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa
| | - Christo Muller
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa
| | - Johan Louw
- Biomedical Research and Innovation Platform, South African Medical Research Council, P.O. Box 19070, Tygerberg, 7505, South Africa
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Kojima S, Gendreau KL, Sher-Chen EL, Gao P, Green CB. Changes in poly(A) tail length dynamics from the loss of the circadian deadenylase Nocturnin. Sci Rep 2015; 5:17059. [PMID: 26586468 PMCID: PMC4653638 DOI: 10.1038/srep17059] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 10/21/2015] [Indexed: 12/15/2022] Open
Abstract
mRNA poly(A) tails are important for mRNA stability and translation, and enzymes that regulate the poly(A) tail length significantly impact protein profiles. There are eleven putative deadenylases in mammals, and it is thought that each targets specific transcripts, although this has not been clearly demonstrated. Nocturnin (NOC) is a unique deadenylase with robustly rhythmic expression and loss of Noc in mice (Noc KO) results in resistance to diet-induced obesity. In an attempt to identify target transcripts of NOC, we performed “poly(A)denylome” analysis, a method that measures poly(A) tail length of transcripts in a global manner, and identified 213 transcripts that have extended poly(A) tails in Noc KO liver. These transcripts share unexpected characteristics: they are short in length, have long half-lives, are actively translated, and gene ontology analyses revealed that they are enriched in functions in ribosome and oxidative phosphorylation pathways. However, most of these transcripts do not exhibit rhythmicity in poly(A) tail length or steady-state mRNA level, despite Noc’s robust rhythmicity. Therefore, even though the poly(A) tail length dynamics seen between genotypes may not result from direct NOC deadenylase activity, these data suggest that NOC exerts strong effects on physiology through direct and indirect control of target mRNAs.
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Affiliation(s)
- Shihoko Kojima
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA, 75390-9111.,Department of Biological Sciences, Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA, 24061
| | - Kerry L Gendreau
- Department of Biological Sciences, Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, VA, USA, 24061
| | - Elaine L Sher-Chen
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA, 75390-9111
| | - Peng Gao
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA, 75390-9111
| | - Carla B Green
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX, USA, 75390-9111
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Comparative Study on the Cytoprotective Effects of Activated Protein C Treatment in Nonsteatotic and Steatotic Livers under Ischemia-Reperfusion Injury. BIOMED RESEARCH INTERNATIONAL 2015; 2015:635041. [PMID: 26539519 PMCID: PMC4619881 DOI: 10.1155/2015/635041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/15/2015] [Accepted: 04/17/2015] [Indexed: 01/28/2023]
Abstract
UNLABELLED Activated protein C (APC) has cytoprotective effects on liver ischemia-reperfusion injury (IRI). However, it is unclear whether APC is beneficial in steatotic liver IRI. We compared the cytoprotective effects of APC in nonsteatotic and steatotic liver IRI. METHODS Mice fed either normal diets (ND mice) or high fat diets (HF mice), were treated with APC or saline (control) and were performed 60 min partial IRI. Moreover, primary steatotic hepatocytes were either untreated or treated with APC and then incubated with H2O2. RESULTS APC significantly reduced serum transaminase levels and the inflammatory cells infiltration compared with control at 4 h in ND mice and at 24 h in HF mice. APC inhibited sinusoidal endothelial injury in ND mice, but not in HF mice. In contrast, APC activated adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in HF mice, but not in ND mice. In the in vitro study, APC significantly increased AMPK phosphorylation, ATP concentration, and survival rates of hepatocytes compared with control. CONCLUSION During IRI in normal liver, APC attenuated initial damage by inhibiting inflammatory cell infiltration and sinusoidal endothelial injury, but not in steatotic liver. However, in steatotic liver, APC might attenuate late damage via activation of AMPK.
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Tashiro H, Kuroda S, Mikuriya Y, Ohdan H. Ischemia–reperfusion injury in patients with fatty liver and the clinical impact of steatotic liver on hepatic surgery. Surg Today 2015; 44:1611-25. [PMID: 24078000 DOI: 10.1007/s00595-013-0736-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 08/22/2013] [Indexed: 12/15/2022]
Abstract
Hepatic steatosis is one of the most common hepatic disorders in developed countries. The epidemic of obesity in developed countries has increased with its attendant complications, including metabolic syndrome and non-alcoholic fatty liver disease. Steatotic livers are particularly vulnerable to ischemia/reperfusion injury, resulting in an increased risk of postoperative morbidity and mortality after liver surgery, including liver transplantation. There is growing understanding of the molecular and cellular mechanisms and therapeutic approaches for treating ischemia/reperfusion injury in patients with steatotic livers. This review discusses the mechanisms underlying the susceptibility of steatotic livers to ischemia/reperfusion injuries, such as mitochondrial dysfunction and signal transduction alterations, and summarizes the clinical impact of steatotic livers in the setting of hepatic resection and liver transplantation. This review also describes potential therapeutic approaches, such as ischemic and pharmacological preconditioning, to prevent ischemia/reperfusion injury in patients with steatotic livers. Other approaches, including machine perfusion, are also under clinical investigation; however, many pharmacological approaches developed through basic research are not yet suitable for clinical application.
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Punicalagin, an active component in pomegranate, ameliorates cardiac mitochondrial impairment in obese rats via AMPK activation. Sci Rep 2015; 5:14014. [PMID: 26369619 PMCID: PMC4642696 DOI: 10.1038/srep14014] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/30/2015] [Indexed: 01/17/2023] Open
Abstract
Obesity is associated with an increasing prevalence of cardiovascular diseases and metabolic syndrome. It is of paramount importance to reduce obesity-associated cardiac dysfunction and impaired energy metabolism. In this study, the activation of the AMP-activated protein kinase (AMPK) pathway by punicalagin (PU), a major ellagitannin in pomegranate was investigated in the heart of a rat obesity model. In male SD rats, eight-week administration of 150 mg/kg pomegranate extract (PE) containing 40% punicalagin sufficiently prevented high-fat diet (HFD)-induced obesity associated accumulation of cardiac triglyceride and cholesterol as well as myocardial damage. Concomitantly, the AMPK pathway was activated, which may account for prevention of mitochondrial loss via upregulating mitochondrial biogenesis and amelioration of oxidative stress via enhancing phase II enzymes in the hearts of HFD rats. Together with the normalized expression of uncoupling proteins and mitochondrial dynamic regulators, PE significantly prevented HFD-induced cardiac ATP loss. Through in vitro cultures, we showed that punicalagin was the predominant component that activated AMPK by quickly decreasing the cellular ATP/ADP ratio specifically in cardiomyocytes. Our findings demonstrated that punicalagin, the major active component in PE, could modulate mitochondria and phase II enzymes through AMPK pathway to prevent HFD-induced cardiac metabolic disorders.
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Hui ST, Parks BW, Org E, Norheim F, Che N, Pan C, Castellani LW, Charugundla S, Dirks DL, Psychogios N, Neuhaus I, Gerszten RE, Kirchgessner T, Gargalovic PS, Lusis AJ. The genetic architecture of NAFLD among inbred strains of mice. eLife 2015; 4:e05607. [PMID: 26067236 PMCID: PMC4493743 DOI: 10.7554/elife.05607] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 06/11/2015] [Indexed: 02/06/2023] Open
Abstract
To identify genetic and environmental factors contributing to the pathogenesis of non-alcoholic fatty liver disease, we examined liver steatosis and related clinical and molecular traits in more than 100 unique inbred mouse strains, which were fed a diet rich in fat and carbohydrates. A >30-fold variation in hepatic TG accumulation was observed among the strains. Genome-wide association studies revealed three loci associated with hepatic TG accumulation. Utilizing transcriptomic data from the liver and adipose tissue, we identified several high-confidence candidate genes for hepatic steatosis, including Gde1, a glycerophosphodiester phosphodiesterase not previously implicated in triglyceride metabolism. We confirmed the role of Gde1 by in vivo hepatic over-expression and shRNA knockdown studies. We hypothesize that Gde1 expression increases TG production by contributing to the production of glycerol-3-phosphate. Our multi-level data, including transcript levels, metabolite levels, and gut microbiota composition, provide a framework for understanding genetic and environmental interactions underlying hepatic steatosis.
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Affiliation(s)
- Simon T Hui
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Brian W Parks
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Elin Org
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Frode Norheim
- Department of Nutrition, Institute of Basic Medical Sciences, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Nam Che
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Calvin Pan
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Lawrence W Castellani
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Sarada Charugundla
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Darwin L Dirks
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
| | - Nikolaos Psychogios
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, United States
| | - Isaac Neuhaus
- Department of Computational Genomics, Bristol-Myers Squibb, Princeton, United States
| | - Robert E Gerszten
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, United States
| | - Todd Kirchgessner
- Department of Cardiovascular Drug Discovery, Bristol-Myers Squibb, Princeton, United States
| | - Peter S Gargalovic
- Department of Computational Genomics, Bristol-Myers Squibb, Princeton, United States
| | - Aldons J Lusis
- Department of Medicine/Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, United States
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Brain death and marginal grafts in liver transplantation. Cell Death Dis 2015; 6:e1777. [PMID: 26043077 PMCID: PMC4669829 DOI: 10.1038/cddis.2015.147] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 02/23/2015] [Accepted: 05/04/2015] [Indexed: 12/22/2022]
Abstract
It is well known that most organs for transplantation are currently procured from brain-dead donors; however, the presence of brain death is an important risk factor in liver transplantation. In addition, one of the mechanisms to avoid the shortage of liver grafts for transplant is the use of marginal livers, which may show higher risk of primary non-function or initial poor function. To our knowledge, very few reviews have focused in the field of liver transplantation using brain-dead donors; moreover, reviews that focused on both brain death and marginal grafts in liver transplantation, both being key risk factors in clinical practice, have not been published elsewhere. The present review aims to describe the recent findings and the state-of-the-art knowledge regarding the pathophysiological changes occurring during brain death, their effects on marginal liver grafts and summarize the more controversial topics of this pathology. We also review the therapeutic strategies designed to date to reduce the detrimental effects of brain death in both marginal and optimal livers, attempting to explain why such strategies have not solved the clinical problem of liver transplantation.
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Koliaki C, Szendroedi J, Kaul K, Jelenik T, Nowotny P, Jankowiak F, Herder C, Carstensen M, Krausch M, Knoefel WT, Schlensak M, Roden M. Adaptation of hepatic mitochondrial function in humans with non-alcoholic fatty liver is lost in steatohepatitis. Cell Metab 2015; 21:739-46. [PMID: 25955209 DOI: 10.1016/j.cmet.2015.04.004] [Citation(s) in RCA: 650] [Impact Index Per Article: 72.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 01/29/2015] [Accepted: 03/31/2015] [Indexed: 02/07/2023]
Abstract
The association of hepatic mitochondrial function with insulin resistance and non-alcoholic fatty liver (NAFL) or steatohepatitis (NASH) remains unclear. This study applied high-resolution respirometry to directly quantify mitochondrial respiration in liver biopsies of obese insulin-resistant humans without (n = 18) or with (n = 16) histologically proven NAFL or with NASH (n = 7) compared to lean individuals (n = 12). Despite similar mitochondrial content, obese humans with or without NAFL had 4.3- to 5.0-fold higher maximal respiration rates in isolated mitochondria than lean persons. NASH patients featured higher mitochondrial mass, but 31%-40% lower maximal respiration, which associated with greater hepatic insulin resistance, mitochondrial uncoupling, and leaking activity. In NASH, augmented hepatic oxidative stress (H2O2, lipid peroxides) and oxidative DNA damage (8-OH-deoxyguanosine) was paralleled by reduced anti-oxidant defense capacity and increased inflammatory response. These data suggest adaptation of the liver ("hepatic mitochondrial flexibility") at early stages of obesity-related insulin resistance, which is subsequently lost in NASH.
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Affiliation(s)
- Chrysi Koliaki
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Julia Szendroedi
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Kirti Kaul
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany
| | - Tomas Jelenik
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany
| | - Peter Nowotny
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany
| | - Frank Jankowiak
- Institute of Pathology, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Christian Herder
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany
| | - Maren Carstensen
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany
| | - Markus Krausch
- Department of General, Visceral and Pediatric Surgery, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Wolfram Trudo Knoefel
- Department of General, Visceral and Pediatric Surgery, Heinrich Heine University, 40225, Düsseldorf, Germany
| | - Matthias Schlensak
- General Surgery Department, St. Martinus Hospital, 40219, Düsseldorf, Germany
| | - Michael Roden
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, 40225, Düsseldorf, Germany; German Center for Diabetes Research (DZD e.V.), 40225, Düsseldorf, Germany; Department of Endocrinology and Diabetology, Medical Faculty, Heinrich Heine University, 40225, Düsseldorf, Germany.
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Zheng G, Lyu J, Liu S, Huang J, Liu C, Xiang D, Xie M, Zeng Q. Silencing of uncoupling protein 2 by small interfering RNA aggravates mitochondrial dysfunction in cardiomyocytes under septic conditions. Int J Mol Med 2015; 35:1525-36. [PMID: 25873251 PMCID: PMC4432931 DOI: 10.3892/ijmm.2015.2177] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 04/02/2015] [Indexed: 01/22/2023] Open
Abstract
Uncoupling protein 2 (UCP2) regulates the production of mitochondrial reactive oxygen species (ROS) and cellular energy transduction under physiological or pathological conditions. In this study, we aimed to determine whether mitochondrial UCP2 plays a protective role in cardiomyocytes under septic conditions. In order to mimic the septic condition, rat embryonic cardiomyoblast-derived H9C2 cells were cultured in the presence of lipopolysaccharide (LPS) plus peptidoglycan G (PepG) and small interfering RNA (siRNA) against UCP2 (siUCP2) was used to suppress UCP2 expression. Reverse transcription quantitative-polymerase chain reaction (RT-qPCR), western blot analysis, transmission electron microscopy (TEM), confocal microscopy and flow cytometry (FCM) were used to detect the mRNA levels, protein levels, mitochondrial morphology and mitochondrial membrane potential (MMP or ΔΨm) in qualitative and quantitative analyses, respectively. Indicators of cell damage [lactate dehydrogenase (LDH), creatine kinase (CK), interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the culture supernatant] and mitochondrial function [ROS, adenosine triphosphate (ATP) and mitochondrial DNA (mtDNA)] were detected. Sepsis enhanced the mRNA and protein expression of UCP2 in the H9C2 cells, damaged the mitochondrial ultrastructure, increased the forward scatter (FSC)/side scatter (SSC) ratio, increased the CK, LDH, TNF-α and IL-6 levels, and lead to the dissipation of MMP, as well as the overproduction of ROS; in addition, the induction of sepsis led to a decrease in ATP levels and the deletion of mtDNA. The silencing of UCP2 aggravated H9C2 cell damage and mitochondrial dysfunction. In conclusion, our data demonstrate that mitochondrial morphology and funtion are damaged in cardiomyocytes under septic conditions, while the silencing of UCP2 using siRNA aggravated this process, indicating that UCP2 may play a protective role in cardiomyocytes under septic conditions.
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Affiliation(s)
- Guilang Zheng
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Juanjuan Lyu
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Shu Liu
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Jinda Huang
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Cui Liu
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Dan Xiang
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Meiyan Xie
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
| | - Qiyi Zeng
- Department of Pediatrics, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, P.R. China
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Chu MJJ, Hickey AJR, Jiang Y, Petzer A, Bartlett ASJR, Phillips ARJ. Mitochondrial dysfunction in steatotic rat livers occurs because a defect in complex i makes the liver susceptible to prolonged cold ischemia. Liver Transpl 2015; 21:396-407. [PMID: 25312517 DOI: 10.1002/lt.24024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2014] [Accepted: 10/06/2014] [Indexed: 01/12/2023]
Abstract
Steatotic livers are susceptible to cold ischemia, which is thought to be secondary to mitochondrial dysfunction. Ischemic preconditioning (IPC) has been reported to improve liver function in the setting of warm ischemia/reperfusion injury, but the effect of IPC on steatotic liver mitochondrial function (MF) with cold ischemia has not been previously evaluated. We aimed to evaluate MF with various severities of hepatic steatosis after various durations of cold ischemia storage with or without IPC. Male Sprague-Dawley rats were fed a normal diet or a high-fat/high-sucrose diet for 1, 2, or 4 weeks to induce mild (<30%), moderate (30%-60%), or severe (>60%) macrovesicular steatosis, respectively. Liver MF was tested with high-resolution respirometry after 1.5, 4, 8, 12, 18, and 24 hours of cold ischemia. Rats in each group (n = 10) underwent 10 minutes of IPC or no IPC before cold ischemia. The baseline (time 0) respiration was similar for lean and severely steatotic livers despite decreased mitochondrial complex I (C-I) activity in severely steatotic livers. Hepatic steatosis was associated with increased C-I-mediated leaks and decreased respiratory control ratios (RCRs) after cold ischemia. Mildly, moderately, and severely steatotic livers showed significantly lower RCRs after 8, 1.5, and 1.5 hours of cold ischemia, respectively, in comparison with lean livers. IPC restored RCRs in mildly steatotic livers to levels comparable to those in lean livers for up to 24 hours of cold ischemia via the attenuation of C-I-mediated leaks, but it had no beneficial effect on moderately and severely steatotic livers. In conclusion, steatotic livers exhibited apparent mitochondrial dysfunction through an alteration in C-I activity, and this made them more susceptible to prolonged cold ischemia. The clinically based IPC protocol used here restored MF in cases of mild hepatic steatosis by attenuating C-I-mediated leaks after prolonged cold ischemia, but it did work not in livers with moderate or severe steatosis.
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Affiliation(s)
- Michael J J Chu
- Department of Surgery, University of Auckland, Auckland, New Zealand
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78
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Ferrigno A, Pasqua LGD, Bianchi A, Richelmi P, Vairetti M. Metabolic shift in liver: Correlation between perfusion temperature and hypoxia inducible factor-1α. World J Gastroenterol 2015; 21:1108-1116. [PMID: 25632183 PMCID: PMC4306154 DOI: 10.3748/wjg.v21.i4.1108] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 08/01/2014] [Accepted: 09/30/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To study at what temperature the oxygen carried by the perfusate meets liver requirements in a model of organ perfusion.
METHODS: In this study, we correlated hypoxia inducible factor (HIF)-1α expression to the perfusion temperature and the hepatic oxygen uptake in a model of isolated perfused rat liver. Livers from Wistar rats were perfused for 6 h with an oxygenated medium at 10, 20, 30 and 37 °C. Oxygen uptake was measured by an oxygen probe; lactate dehydrogenase activity, lactate release and glycogen were measured spectrophotometrically; bile flow was gravitationally determined; pH of the perfusate was also evaluated; HIF-1α mRNA and protein expression were analyzed by real time-polymerase chain reaction and ELISA, respectively.
RESULTS: Livers perfused at 10 and 20 °C showed no difference in lactate dehydrogenase release after 6 h of perfusion (0.96 ± 0.23 vs 0.93 ± 0.09 mU/min per g) and had lower hepatic damage as compared to 30 and 37 °C (5.63 ± 0.76 vs 527.69 ± 45.27 mU/min per g, respectively, Ps < 0.01). After 6 h, tissue ATP was significantly higher in livers perfused at 10 and 20 °C than in livers perfused at 30 and 37 °C (0.89 ± 0.06 and 1.16 ± 0.05 vs 0.57 ± 0.09 and 0.33 ± 0.08 nmol/mg, respectively, Ps < 0.01). No sign of hypoxia was observed at 10 and 20 °C, as highlighted by low lactate release respect to livers perfused at 30 and 37 °C (121.4 ± 12.6 and 146.3 ± 7.3 vs 281.8 ± 45.3 and 1094.5 ± 71.7 nmol/mL, respectively, Ps < 0.02), and low relative HIF-1α mRNA (0.40 ± 0.08 and 0.20 ± 0.03 vs 0.60 ± 0.20 and 1.47 ± 0.30, respectively, Ps < 0.05) and protein (3.72 ± 0.16 and 3.65 ± 0.06 vs 4.43 ± 0.41 and 6.44 ± 0.82, respectively, Ps < 0.05) expression.
CONCLUSION: Livers perfused at 10 and 20 °C show no sign of liver injury or anaerobiosis, in contrast to livers perfused at 30 and 37 °C.
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Uncoupling lipid metabolism from inflammation through fatty acid binding protein-dependent expression of UCP2. Mol Cell Biol 2015; 35:1055-65. [PMID: 25582199 DOI: 10.1128/mcb.01122-14] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Chronic inflammation in obese adipose tissue is linked to endoplasmic reticulum (ER) stress and systemic insulin resistance. Targeted deletion of the murine fatty acid binding protein (FABP4/aP2) uncouples obesity from inflammation although the mechanism underlying this finding has remained enigmatic. Here, we show that inhibition or deletion of FABP4/aP2 in macrophages results in increased intracellular free fatty acids (FFAs) and elevated expression of uncoupling protein 2 (UCP2) without concomitant increases in UCP1 or UCP3. Silencing of UCP2 mRNA in FABP4/aP2-deficient macrophages negated the protective effect of FABP loss and increased ER stress in response to palmitate or lipopolysaccharide (LPS). Pharmacologic inhibition of FABP4/aP2 with the FABP inhibitor HTS01037 also upregulated UCP2 and reduced expression of BiP, CHOP, and XBP-1s. Expression of native FABP4/aP2 (but not the non-fatty acid binding mutant R126Q) into FABP4/aP2 null cells reduced UCP2 expression, suggesting that the FABP-FFA equilibrium controls UCP2 expression. FABP4/aP2-deficient macrophages are resistant to LPS-induced mitochondrial dysfunction and exhibit decreased mitochondrial protein carbonylation and UCP2-dependent reduction in intracellular reactive oxygen species. These data demonstrate that FABP4/aP2 directly regulates intracellular FFA levels and indirectly controls macrophage inflammation and ER stress by regulating the expression of UCP2.
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Affiliation(s)
| | - Akihiko Ohshige
- Digestive and Lifestyle Diseases, Kagoshima University Graduate School of Medical and Dental Sciences
| | - Hirofumi Uto
- Center for Digestive and Liver Diseases, Miyazaki Medical Center Hospital
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81
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Wei W, Dirsch O, Mclean AL, Zafarnia S, Schwier M, Dahmen U. Rodent models and imaging techniques to study liver regeneration. Eur Surg Res 2014; 54:97-113. [PMID: 25402256 DOI: 10.1159/000368573] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/19/2014] [Indexed: 12/16/2022]
Abstract
The liver has the unique capability of regeneration from various injuries. Different animal models and in vitro methods are used for studying the processes and mechanisms of liver regeneration. Animal models were established either by administration of hepatotoxic chemicals or by surgical approach. The administration of hepatotoxic chemicals results in the death of liver cells and in subsequent hepatic regeneration and tissue repair. Surgery includes partial hepatectomy and portal vein occlusion or diversion: hepatectomy leads to compensatory regeneration of the remnant liver lobe, whereas portal vein occlusion leads to atrophy of the ipsilateral lobe and to compensatory regeneration of the contralateral lobe. Adaptation of modern radiological imaging technologies to the small size of rodents made the visualization of rodent intrahepatic vascular anatomy possible. Advanced knowledge of the detailed intrahepatic 3D anatomy enabled the establishment of refined surgical techniques. The same technology allows the visualization of hepatic vascular regeneration. The development of modern histological image analysis tools improved the quantitative assessment of hepatic regeneration. Novel image analysis tools enable us to quantify reliably and reproducibly the proliferative rate of hepatocytes using whole-slide scans, thus reducing the sampling error. In this review, the refined rodent models and the newly developed imaging technology to study liver regeneration are summarized. This summary helps to integrate the current knowledge of liver regeneration and promises an enormous increase in hepatological knowledge in the near future.
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Affiliation(s)
- Weiwei Wei
- Department of General, Visceral and Vascular Surgery, Jena University Hospital, Jena, Germany
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82
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Increased body fat mass and tissue lipotoxicity associated with ovariectomy or high-fat diet differentially affects bone and skeletal muscle metabolism in rats. Eur J Nutr 2014; 54:1139-49. [PMID: 25370302 DOI: 10.1007/s00394-014-0790-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/22/2014] [Indexed: 12/21/2022]
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83
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Zou X, Yan C, Shi Y, Cao K, Xu J, Wang X, Chen C, Luo C, Li Y, Gao J, Pang W, Zhao J, Zhao F, Li H, Zheng A, Sun W, Long J, Szeto IMY, Zhao Y, Dong Z, Zhang P, Wang J, Lu W, Zhang Y, Liu J, Feng Z. Mitochondrial dysfunction in obesity-associated nonalcoholic fatty liver disease: the protective effects of pomegranate with its active component punicalagin. Antioxid Redox Signal 2014; 21:1557-70. [PMID: 24393106 PMCID: PMC4175030 DOI: 10.1089/ars.2013.5538] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AIMS Punicalagin (PU) is one of the major ellagitannins found in the pomegranate (Punica granatum), which is a popular fruit with several health benefits. So far, no studies have evaluated the effects of PU on nonalcoholic fatty liver disease (NAFLD). Our work aims at studying the effect of PU-enriched pomegranate extract (PE) on high fat diet (HFD)-induced NAFLD. RESULTS PE administration at a dosage of 150 mg/kg/day significantly inhibited HFD-induced hyperlipidemia and hepatic lipid deposition. As major contributors to NAFLD, increased expression of pro-inflammatory cytokines such as tumor necrosis factor-alpha, interleukins 1, 4, and 6 as well as augmented oxidative stress in hepatocytes followed by nuclear factor (erythroid-derived-2)-like 2 (Nrf2) activation were normalized through PE supplementation. In addition, PE treatment reduced uncoupling protein 2 (UCP2) expression, restored ATP content, suppressed mitochondrial protein oxidation, and improved mitochondrial complex activity in the liver. In contrast, mitochondrial content was not affected despite increased peroxisomal proliferator-activated receptor-gamma coactivator-1α (PGC-1α) and elevated expression of genes related to mitochondrial beta-oxidation after PE treatment. Finally, PU was identified as the predominant active component of PE with regard to the lowering of triglyceride and cholesterol content in HepG2 cells, and both PU- and PE-protected cells from palmitate induced mitochondrial dysfunction and insulin resistance. INNOVATION Our work presents the beneficial effects of PE on obesity-associated NAFLD and multiple risk factors. PU was proposed to be the major active component. CONCLUSIONS By promoting mitochondrial function, eliminating oxidative stress and inflammation, PU may be a useful nutrient for the treatment of NAFLD.
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Affiliation(s)
- Xuan Zou
- 1 The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Frontier Institute of Science and Technology, Xi'an Jiaotong University , Xi'an, China
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84
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Reiniers MJ, van Golen RF, van Gulik TM, Heger M. Reactive oxygen and nitrogen species in steatotic hepatocytes: a molecular perspective on the pathophysiology of ischemia-reperfusion injury in the fatty liver. Antioxid Redox Signal 2014; 21:1119-42. [PMID: 24294945 PMCID: PMC4123468 DOI: 10.1089/ars.2013.5486] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 11/14/2013] [Accepted: 12/02/2013] [Indexed: 12/13/2022]
Abstract
SIGNIFICANCE Hepatic ischemia-reperfusion (IR) injury results from the temporary deprivation of hepatic blood supply and is a common side effect of major liver surgery (i.e., transplantation or resection). IR injury, which in most severe cases culminates in acute liver failure, is particularly pronounced in livers that are affected by non-alcoholic fatty liver disease (NAFLD). In NAFLD, fat-laden hepatocytes are damaged by chronic oxidative/nitrosative stress (ONS), a state that is acutely exacerbated during IR, leading to extensive parenchymal damage. RECENT ADVANCES NAFLD triggers ONS via increased (extra)mitochondrial fatty acid oxidation and activation of the unfolded protein response. ONS is associated with widespread protein and lipid (per)oxidation, which reduces the hepatic antioxidative capacity and shifts the intracellular redox status toward an oxidized state. Moreover, activation of the transcription factor peroxisome proliferator-activated receptor α induces expression of mitochondrial uncoupling protein 2, resulting in depletion of cellular energy (ATP) reserves. The reduction in intracellular antioxidants and ATP in fatty livers consequently gives rise to severe ONS and necrotic cell death during IR. CRITICAL ISSUES Despite the fact that ONS mediates both NAFLD and IR injury, the interplay between the two conditions has never been described in detail. An integrative overview of the pathophysiology of NAFLD that renders steatotic hepatocytes more vulnerable to IR injury is therefore presented in the context of ONS. FUTURE DIRECTIONS Effective methods should be devised to alleviate ONS and the consequences thereof in NAFLD before surgery in order to improve resilience of fatty livers to IR injury.
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Affiliation(s)
- Megan J Reiniers
- Department of Surgery, Surgical Laboratory, Academic Medical Center, University of Amsterdam , Amsterdam, The Netherlands
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Fealy CE, Mulya A, Lai N, Kirwan JP. Exercise training decreases activation of the mitochondrial fission protein dynamin-related protein-1 in insulin-resistant human skeletal muscle. J Appl Physiol (1985) 2014; 117:239-45. [PMID: 24947026 PMCID: PMC4122691 DOI: 10.1152/japplphysiol.01064.2013] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 06/12/2014] [Indexed: 02/03/2023] Open
Abstract
Defects in mitochondrial dynamics, the processes of fission, fusion, and mitochondrial autophagy, may contribute to metabolic disease including type 2 diabetes. Dynamin-related protein-1 (Drp1) is a GTPase protein that plays a central role in mitochondrial fission. We hypothesized that aerobic exercise training would decrease Drp1 Ser(616) phosphorylation and increase fat oxidation and insulin sensitivity in obese (body mass index: 34.6 ± 0.8 kg/m(2)) insulin-resistant adults. Seventeen subjects performed supervised exercise for 60 min/day, 5 days/wk at 80-85% of maximal heart rate for 12 wk. Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp, and fat oxidation was determined by indirect calorimetry. Skeletal muscle biopsies were obtained from the vastus lateralis muscle before and after the 12-wk program. The exercise intervention increased insulin sensitivity 2.1 ± 0.2-fold (P < 0.01) and fat oxidation 1.3 ± 0.3-fold (P < 0.01). Phosphorylation of Drp1 at Ser(616) was decreased (pre vs. post: 0.81 ± 0.15 vs. 0.58 ± 0.14 arbitrary units; P < 0.05) following the intervention. Furthermore, reductions in Drp1 Ser(616) phosphorylation were negatively correlated with increases in fat oxidation (r = -0.58; P < 0.05) and insulin sensitivity (rho = -0.52; P < 0.05). We also examined expression of genes related to mitochondrial dynamics. Dynamin1-like protein (DNM1L; P < 0.01), the gene that codes for Drp1, and Optic atrophy 1 (OPA1; P = 0.05) were significantly upregulated following the intervention, while there was a trend towards an increase in expression of both mitofusin protein MFN1 (P = 0.08) and MFN2 (P = 0.07). These are the first data to suggest that lifestyle-mediated improvements in substrate metabolism and insulin sensitivity in obese insulin-resistant adults may be regulated through decreased activation of the mitochondrial fission protein Drp1.
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Affiliation(s)
- Ciaran E Fealy
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio; Department of Biomedical Sciences, Kent State University, Kent, Ohio
| | - Anny Mulya
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio; Metabolic Translational Research Center, Cleveland Clinic, Cleveland, Ohio; and
| | - Nicola Lai
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio
| | - John P Kirwan
- Department of Pathobiology, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio; Metabolic Translational Research Center, Cleveland Clinic, Cleveland, Ohio; and
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Ob/ob mouse livers show decreased oxidative phosphorylation efficiencies and anaerobic capacities after cold ischemia. PLoS One 2014; 9:e100609. [PMID: 24956382 PMCID: PMC4067359 DOI: 10.1371/journal.pone.0100609] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 05/28/2014] [Indexed: 01/26/2023] Open
Abstract
Background Hepatic steatosis is a major risk factor for graft failure in liver transplantation. Hepatic steatosis shows a greater negative influence on graft function following prolonged cold ischaemia. As the impact of steatosis on hepatocyte metabolism during extended cold ischaemia is not well-described, we compared markers of metabolic capacity and mitochondrial function in steatotic and lean livers following clinically relevant durations of cold preservation. Methods Livers from 10-week old leptin-deficient obese (ob/ob, n = 9) and lean C57 mice (n = 9) were preserved in ice-cold University of Wisconsin solution. Liver mitochondrial function was then assessed using high resolution respirometry after 1.5, 3, 5, 8, 12, 16 and 24 hours of storage. Metabolic marker enzymes for anaerobiosis and mitochondrial mass were also measured in conjunction with non-bicarbonate tissue pH buffering capacity. Results Ob/ob and lean mice livers showed severe (>60%) macrovesicular and mild (<30%) microvesicular steatosis on Oil Red O staining, respectively. Ob/ob livers had lower baseline enzymatic complex I activity but similar adenosine triphosphate (ATP) levels compared to lean livers. During cold storage, the respiratory control ratio and complex I-fueled phosphorylation deteriorated approximately twice as fast in ob/ob livers compared to lean livers. Ob/ob livers also demonstrated decreased ATP production capacities at all time-points analyzed compared to lean livers. Ob/ob liver baseline lactate dehydrogenase activities and intrinsic non-bicarbonate buffering capacities were depressed by 60% and 40%, respectively compared to lean livers. Conclusions Steatotic livers have impaired baseline aerobic and anaerobic capacities compared to lean livers, and mitochondrial function indices decrease particularly from after 5 hours of cold preservation. These data provide a mechanistic basis for the clinical recommendation of shorter cold storage durations in steatotic donor livers.
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Kim J, Kim YS, Lee HA, Lim JY, Kim M, Kwon O, Ko HC, Kim SJ, Shin JH, Kim Y. Sasa quelpaertensisLeaf Extract Improves High Fat Diet-Induced Lipid Abnormalities and Regulation of Lipid Metabolism Genes in Rats. J Med Food 2014; 17:571-81. [PMID: 24738745 DOI: 10.1089/jmf.2013.2916] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Jina Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Yoo-Sun Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Hyun Ah Lee
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Ji Ye Lim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Mina Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Oran Kwon
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
| | - Hee-Chul Ko
- Jeju Sasa Industry Development Agency, Jeju National University, Jeju-si, Jeju, Korea
| | - Se-Jae Kim
- Department of Biology, Jeju National University, Jeju-si, Jeju, Korea
| | - Jae-Ho Shin
- Department of Biomedical Laboratory Science, Eulji University, Seongnam-si, Kyeonggi-do, Korea
| | - Yuri Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, Korea
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Meli R, Mattace Raso G, Calignano A. Role of innate immune response in non-alcoholic Fatty liver disease: metabolic complications and therapeutic tools. Front Immunol 2014; 5:177. [PMID: 24795720 PMCID: PMC4005965 DOI: 10.3389/fimmu.2014.00177] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 04/04/2014] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is currently the most common liver disease worldwide, both in adults and children. It is characterized by an aberrant lipid storage in hepatocytes, named hepatic steatosis. Simple steatosis remains a benign process in most affected patients, while some of them develop superimposed necroinflammatory activity with a non-specific inflammatory infiltrate and a progression to non-alcoholic steatohepatitis with or without fibrosis. Deep similarity and interconnections between innate immune cells and those of liver parenchyma have been highlighted and showed to play a key role in the development of chronic liver disease. The liver can be considered as an “immune organ” because it hosts non-lymphoid cells, such as macrophage Kupffer cells, stellate and dendritic cells, and lymphoid cells. Many of these cells are components of the classic innate immune system, enabling the liver to play a major role in response to pathogens. Although the liver provides a “tolerogenic” environment, aberrant activation of innate immune signaling may trigger “harmful” inflammation that contributes to tissue injury, fibrosis, and carcinogenesis. Pathogen recognition receptors, such as toll-like receptors and nucleotide oligomerization domain-like receptors, are responsible for the recognition of immunogenic signals, and represent the major conduit for sensing hepatic and non-hepatic noxious stimuli. A pivotal role in liver inflammation is also played by cytokines, which can initiate or have a part in immune response, triggering hepatic intracellular signaling pathways. The sum of inflammatory signals and deranged substrate handling induce most of the metabolic alteration traits: insulin resistance, obesity, diabetes, hyperlipidemia, and their compounded combined effects. In this review, we discuss the relevant role of innate immune cell activation in relation to NAFLD, the metabolic complications associated to this pathology, and the possible pharmacological tools.
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Affiliation(s)
- Rosaria Meli
- Department of Pharmacy, University of Naples "Federico II" , Naples , Italy
| | | | - Antonio Calignano
- Department of Pharmacy, University of Naples "Federico II" , Naples , Italy
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89
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Evaluation of dietary effects on hepatic lipids in high fat and placebo diet fed rats by in vivo MRS and LC-MS techniques. PLoS One 2014; 9:e91436. [PMID: 24638096 PMCID: PMC3956606 DOI: 10.1371/journal.pone.0091436] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 02/12/2014] [Indexed: 11/25/2022] Open
Abstract
Background & Aims Dietary saturated fatty acids contribute to the development of fatty liver and have pathogenic link to systemic inflammation. We investigated the effects of dietary fat towards the pathogenesis of non-alcoholic fatty liver disease by longitudinal in vivo magnetic resonance spectroscopy (MRS) and in vitro liquid chromatography coupled with mass spectrometry (LC-MS). Methods All measurements were performed on rats fed with high fat diet (HFD) and chow diet for twenty four weeks. Longitudinal MRS measurements were performed at the 12th, 18th and 24th weeks. Liver tissues were analyzed by LC-MS, histology and gene transcription studies after terminal in vivo experiments. Results Liver fat content of HFD rats for all ages was significantly (P<0.05) higher compared to their respective chow diet fed rats. Unsaturation indices estimated from MRS and LC-MS data of chow diet fed rats were significantly higher (P<0.05) than HFD fed rats. The concentration of triglycerides 48∶1, 48∶2, 50∶1, 50∶2, 50∶3, 52∶1, 52∶2, 52∶3, 54∶3 and 54∶2 was significantly higher (P<0.05) in HFD rats. The concentration for some polyunsaturated triglycerides 54∶7, 56∶8, 56∶7, 58∶11, 58∶10, 58∶9, 58∶8 and 60∶10 was significantly higher (P<0.05) in chow diet fed rats compared to HFD rats. Lysophospholipid concentrations including LPC and LPE were higher in HFD rats at 24 weeks indicating the increased risk of diabetes. The expression of CD36, PPARα, SCD1, SREBF1 and UCP2 were significantly upregulated in HFD rats. Conclusions We demonstrated the early changes in saturated and unsaturated lipid composition in fatty liver by in vivo MRS and ex vivo LC-MS. The higher LPC concentration in HFD rats indicated a higher risk of developing diabetes. Early metabolic perturbations causing changes in lipid composition can be evaluated by the unsaturation index and correlated to the non alcoholic fatty liver disease.
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90
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Al Rajabi A, Castro GSF, da Silva RP, Nelson RC, Thiesen A, Vannucchi H, Vine DF, Proctor SD, Field CJ, Curtis JM, Jacobs RL. Choline supplementation protects against liver damage by normalizing cholesterol metabolism in Pemt/Ldlr knockout mice fed a high-fat diet. J Nutr 2014; 144:252-7. [PMID: 24368431 DOI: 10.3945/jn.113.185389] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dietary choline is required for proper structure and dynamics of cell membranes, lipoprotein synthesis, and methyl-group metabolism. In mammals, choline is synthesized via phosphatidylethanolamine N-methyltransferase (Pemt), which converts phosphatidylethanolamine to phosphatidylcholine. Pemt(-/-) mice have impaired VLDL secretion and developed fatty liver when fed a high-fat (HF) diet. Because of the reduction in plasma lipids, Pemt(-/-)/low-density lipoprotein receptor knockout (Ldlr(-/-)) mice are protected from atherosclerosis. The goal of this study was to investigate the importance of dietary choline in the metabolic phenotype of Pemt(-/-)/Ldlr(-/-) male mice. At 10-12 wk of age, Pemt(+/+)/Ldlr(-/-) (HF(+/+)) and half of the Pemt(-/-)/Ldlr(-/-) (HF(-/-)) mice were fed an HF diet with normal (1.3 g/kg) choline. The remaining Pemt(-/-)/Ldlr(-/-) mice were fed an HF diet supplemented (5 g/kg) with choline (HFCS(-/-) mice). The HF diet contained 60% of calories from fat and 1% cholesterol, and the mice were fed for 16 d. HF(-/-) mice lost weight and developed hepatomegaly, steatohepatitis, and liver damage. Hepatic concentrations of free cholesterol, cholesterol-esters, and triglyceride (TG) were elevated by 30%, 1.1-fold and 3.1-fold, respectively, in HF(-/-) compared with HF(+/+) mice. Choline supplementation normalized hepatic cholesterol, but not TG, and dramatically improved liver function. The expression of genes involved in cholesterol transport and esterification increased by 50% to 5.6-fold in HF(-/-) mice when compared with HF(+/+) mice. Markers of macrophages, oxidative stress, and fibrosis were elevated in the HF(-/-) mice. Choline supplementation normalized the expression of these genes. In conclusion, HF(-/-) mice develop liver failure associated with altered cholesterol metabolism when fed an HF/normal choline diet. Choline supplementation normalized cholesterol metabolism, which was sufficient to prevent nonalcoholic steatohepatitis development and improve liver function. Our data suggest that choline can promote liver health by maintaining cholesterol homeostasis.
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Affiliation(s)
- Ala Al Rajabi
- Departments of Agricultural, Food, and Nutritional Science, and
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91
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Physical exercise prevents and mitigates non-alcoholic steatohepatitis-induced liver mitochondrial structural and bioenergetics impairments. Mitochondrion 2014; 15:40-51. [DOI: 10.1016/j.mito.2014.03.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/14/2014] [Accepted: 03/31/2014] [Indexed: 12/11/2022]
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92
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CEACAM1 loss links inflammation to insulin resistance in obesity and non-alcoholic steatohepatitis (NASH). Semin Immunopathol 2013; 36:55-71. [PMID: 24258517 DOI: 10.1007/s00281-013-0407-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/13/2013] [Indexed: 02/06/2023]
Abstract
Mounting epidemiological evidence points to an association between metabolic syndrome and non-alcoholic steatohepatitis (NASH), an increasingly recognized new epidemic. NASH pathologies include hepatocellular ballooning, lobular inflammation, hepatocellular injury, apoptosis, and hepatic fibrosis. We will review the relationship between insulin resistance and inflammation in visceral obesity and NASH in an attempt to shed more light on the pathogenesis of these major metabolic diseases. Moreover, we will identify loss of the carcinoembryonic antigen-related cell adhesion molecule 1 as a unifying mechanism linking the immunological and metabolic abnormalities in NASH.
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93
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Cheng G, Palanisamy AP, Evans ZP, Sutter AG, Jin L, Singh I, May H, Schmidt MG, Chavin KD. Cerulenin blockade of fatty acid synthase reverses hepatic steatosis in ob/ob mice. PLoS One 2013; 8:e75980. [PMID: 24086674 PMCID: PMC3785413 DOI: 10.1371/journal.pone.0075980] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/18/2013] [Indexed: 12/14/2022] Open
Abstract
Fatty liver or hepatic steatosis is a common health problem associated with abnormal liver function and increased susceptibility to ischemia/reperfusion injury. The objective of this study was to investigate the effect of the fatty acid synthase inhibitor cerulenin on hepatic function in steatotic ob/ob mice. Different dosages of cerulenin were administered intraperitoneally to ob/ob mice for 2 to 7 days. Body weight, serum AST/ALT, hepatic energy state, and gene expression patterns in ob/ob mice were examined. We found that cerulenin treatment markedly improved hepatic function in ob/ob mice. Serum AST/ALT levels were significantly decreased and hepatic ATP levels increased in treated obese mice compared to obese controls, accompanied by fat depletion in the hepatocyte. Expression of peroxisome proliferator-activated receptors α and γ and uncoupling protein 2 were suppressed with cerulenin treatment and paralleled changes in AST/ALT levels. Hepatic glutathione content were increased in some cases and apoptotic activity in the steatotic livers was minimally changed with cerulenin treatment. In conclusion, these results demonstrate that fatty acid synthase blockade constitutes a novel therapeutic strategy for altering hepatic steatosis at non-stressed states in obese livers.
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Affiliation(s)
- Gang Cheng
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Arun P. Palanisamy
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
- * E-mail:
| | - Zachary P. Evans
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Alton G. Sutter
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Lan Jin
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Inderjit Singh
- Department of Pediatrics, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Harold May
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Michael G. Schmidt
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Kenneth D. Chavin
- Divisions of Transplant Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
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94
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Obeid OA. Low phosphorus status might contribute to the onset of obesity. Obes Rev 2013; 14:659-64. [PMID: 23679666 DOI: 10.1111/obr.12039] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/08/2013] [Accepted: 03/22/2013] [Indexed: 01/19/2023]
Abstract
Overweight and obesity are becoming global health problems. Although genetics certainly plays a role, weight gain is ultimately the result of a failure in the balance between energy expenditure and energy intake. Obesity during the past few decades was paralleled with several changes in dietary habits favouring low phosphorus consumption. This is believed to compromise adenosine triphosphate (ATP) production that is involved in the regulation of energy metabolism. Ingestion of high-carbohydrate-low phosphorus food is known to increase insulin release, to simultaneously stimulate peripheral uptake of phosphorus and the phosphorylation of many compounds. This creates a competition for phosphorus that compromises its availability for ATP production, possibly translated into low diet-induced thermogenesis. Moreover, reduced hepatic ATP production is believed to be transmitted through neural afferents to the central nervous system, resulting in an increase in food intake. On the other hand, the positive relation between phosphorus and red blood cell 2,3-diphosphoglycerate, which reduces oxygen affinity to haemoglobin, would be expected to reduce the capacity for physical activity. In line with that, plasma phosphorus status was reported to be inversely related to body weight. Adequate intakes of phosphorus are thus potentially protective against rising obesity epidemic across the globe.
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Affiliation(s)
- O A Obeid
- Department of Nutrition and Food Science, Faculty of Agricultural and Food Sciences, American University of Beirut, Beirut, Lebanon.
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95
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Fukumori R, Takarada T, Nakazato R, Fujikawa K, Kou M, Hinoi E, Yoneda Y. Selective inhibition by ethanol of mitochondrial calcium influx mediated by uncoupling protein-2 in relation to N-methyl-D-aspartate cytotoxicity in cultured neurons. PLoS One 2013; 8:e69718. [PMID: 23874988 PMCID: PMC3713054 DOI: 10.1371/journal.pone.0069718] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 06/11/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND We have shown the involvement of mitochondrial uncoupling protein-2 (UCP2) in the cytotoxicity by N-methyl-D-aspartate receptor (NMDAR) through a mechanism relevant to the increased mitochondrial Ca(2+) levels in HEK293 cells with acquired NMDAR channels. Here, we evaluated pharmacological profiles of ethanol on the NMDA-induced increase in mitochondrial Ca(2+) levels in cultured murine neocortical neurons. METHODOLOGY/PRINCIPAL FINDINGS In neurons exposed to glutamate or NMDA, a significant increase was seen in mitochondrial Ca(2+) levels determined by Rhod-2 at concentrations of 0.1 to 100 µM. Further addition of 250 mM ethanol significantly inhibited the increase by glutamate and NMDA in Rhod-2 fluorescence, while similarly potent inhibition of the NMDA-induced increase was seen after exposure to ethanol at 50 to 250 mM in cultured neurons. Lentiviral overexpression of UCP2 significantly accelerated the increase by NMDA in Rhod-2 fluorescence in neurons, without affecting Fluo-3 fluorescence for intracellular Ca(2+) levels. In neurons overexpressing UCP2, exposure to ethanol resulted in significantly more effective inhibition of the NMDA-induced increase in mitochondrial free Ca(2+) levels than in those without UCP2 overexpression, despite a similarly efficient increase in intracellular Ca(2+) levels irrespective of UCP2 overexpression. Overexpression of UCP2 significantly increased the number of dead cells in a manner prevented by ethanol in neurons exposed to glutamate. In HEK293 cells with NMDAR containing GluN2B subunit, more efficient inhibition was similarly induced by ethanol at 50 and 250 mM on the NMDA-induced increase in mitochondrial Ca(2+) levels than in those with GluN2A subunit. Decreased protein levels of GluN2B, but not GluN2A, subunit were seen in immunoprecipitates with UCP2 from neurons with brief exposure to ethanol at concentrations over 50 mM. CONCLUSIONS/SIGNIFICANCE Ethanol could inhibit the interaction between UCP2 and NMDAR channels to prevent the mitochondrial Ca(2+) incorporation and cell death after NMDAR activation in neurons.
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Affiliation(s)
- Ryo Fukumori
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Takeshi Takarada
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Ryota Nakazato
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Koichi Fujikawa
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Miki Kou
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Eiichi Hinoi
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
| | - Yukio Yoneda
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School, Kanazawa, Ishikawa, Japan
- * E-mail:
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96
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Takarada T, Fukumori R, Yoneda Y. [Mitochondrial uncoupling protein-2 in glutamate neurotoxicity]. Nihon Yakurigaku Zasshi 2013; 142:13-16. [PMID: 23842222 DOI: 10.1254/fpj.142.13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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97
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Ucar F, Sezer S, Erdogan S, Akyol S, Armutcu F, Akyol O. The relationship between oxidative stress and nonalcoholic fatty liver disease: Its effects on the development of nonalcoholic steatohepatitis. Redox Rep 2013; 18:127-33. [PMID: 23743495 DOI: 10.1179/1351000213y.0000000050] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are the most common underlying causes of chronic liver injury. They are associated with a wide spectrum of hepatic disorders including basic steatosis, steatohepatitis, and cirrhosis. The molecular and cellular mechanisms underlying hepatic injury in NAFLD and NASH are still unknown. This review describes the roles of oxidative stress and inflammatory responses in the pathogenesis of NAFLD and its progression to NASH.
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Affiliation(s)
- Fatma Ucar
- Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey.
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98
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Almeida F, Salgueiro-Paradigorria C, Franzói-de-Moraes S, Nachbar R, Chimin P, Natali M. Aerobic physical training after weaning improves liver histological and metabolic characteristics of diet-induced obese rats. Sci Sports 2013. [DOI: 10.1016/j.scispo.2012.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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99
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Exhaustive training increases uncoupling protein 2 expression and decreases Bcl-2/Bax ratio in rat skeletal muscle. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:780719. [PMID: 23365696 PMCID: PMC3556863 DOI: 10.1155/2013/780719] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 11/27/2012] [Accepted: 12/19/2012] [Indexed: 01/06/2023]
Abstract
This work investigates the effects of oxidative stress due to exhaustive training on uncoupling protein 2 (UCP2) and Bcl-2/Bax in rat skeletal muscles. A total of 18 Sprague-Dawley female rats were randomly divided into three groups: the control group (CON), the trained control group (TC), and the exhaustive trained group (ET). Malondialdehyde (MDA), superoxide dismutase (SOD), xanthine oxidase (XOD), ATPase, UCP2, and Bcl-2/Bax ratio in red gastrocnemius muscles were measured. Exhaustive training induced ROS increase in red gastrocnemius muscles, which led to a decrease in the cell antiapoptotic ability (Bcl-2/Bax ratio). An increase in UCP2 expression can reduce ROS production and affect mitochondrial energy production. Thus, oxidative stress plays a significant role in overtraining.
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100
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Arai T, Kim HJ, Hirako S, Nakasatomi M, Chiba H, Matsumoto A. Effects of dietary fat energy restriction and fish oil feeding on hepatic metabolic abnormalities and insulin resistance in KK mice with high-fat diet-induced obesity. J Nutr Biochem 2013; 24:267-73. [DOI: 10.1016/j.jnutbio.2012.06.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 06/01/2012] [Accepted: 06/02/2012] [Indexed: 12/22/2022]
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