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Haran A, Bergel M, Kleiman D, Hefetz L, Israeli H, Weksler-Zangen S, Agranovich B, Abramovich I, Ben-Haroush Schyr R, Gottlieb E, Ben-Zvi D. Differential effects of bariatric surgery and caloric restriction on hepatic one-carbon and fatty acid metabolism. iScience 2023; 26:107046. [PMID: 37389181 PMCID: PMC10300224 DOI: 10.1016/j.isci.2023.107046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 03/24/2023] [Accepted: 06/01/2023] [Indexed: 07/01/2023] Open
Abstract
Weight loss interventions, including dietary changes, pharmacotherapy, or bariatric surgery, prevent many of the adverse consequences of obesity, and may also confer intervention-specific benefits beyond those seen with decreased weight alone. We compared the molecular effects of different interventions on liver metabolism to understand the mechanisms underlying these benefits. Male rats on a high-fat, high-sucrose diet underwent sleeve gastrectomy (SG) or intermittent fasting with caloric restriction (IF-CR), achieving equivalent weight loss. The interventions were compared to ad-libitum (AL)-fed controls. Analysis of liver and blood metabolome and transcriptome revealed distinct and sometimes contrasting metabolic effects between the two interventions. SG primarily influenced one-carbon metabolic pathways, whereas IF-CR increased de novo lipogenesis and glycogen storage. These findings suggest that the unique metabolic pathways affected by SG and IF-CR contribute to their distinct clinical benefits, with bariatric surgery potentially influencing long-lasting changes through its effect on one-carbon metabolism.
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Affiliation(s)
- Arnon Haran
- Department of Hematology, Haddasah Medical Center, Jerusalem, Israel
| | - Michael Bergel
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Doron Kleiman
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Liron Hefetz
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Hadar Israeli
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | | | - Bella Agranovich
- Department of Cell Biology and Cancer Science, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Ifat Abramovich
- Department of Cell Biology and Cancer Science, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Rachel Ben-Haroush Schyr
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
| | - Eyal Gottlieb
- Department of Cell Biology and Cancer Science, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Danny Ben-Zvi
- Department of Developmental Biology and Cancer Research, Institute for Medical Research Israel-Canada, The Hebrew University of Jerusalem-Hadassah Medical School, Jerusalem, Israel
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Kadota A, Iwakoshi-Ukena E, Fukumura K, Shikano K, Narimatsu Y, Furumitsu M, Ukena K. Effects of Irregular Feeding on the Daily Fluctuations in mRNA Expression of the Neurosecretory Protein GL and Neurosecretory Protein GM Genes in the Mouse Hypothalamus. Int J Mol Sci 2021; 22:2109. [PMID: 33672695 PMCID: PMC7924315 DOI: 10.3390/ijms22042109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/15/2021] [Accepted: 02/18/2021] [Indexed: 01/25/2023] Open
Abstract
Circadian desynchrony induced by a long period of irregular feeding leads to metabolic diseases, such as obesity and diabetes mellitus. The recently identified neurosecretory protein GL (NPGL) and neurosecretory protein GM (NPGM) are hypothalamic small proteins that stimulate food intake and fat accumulation in several animals. To clarify the mechanisms that evoke feeding behavior and induce energy metabolism at the appropriate times in accordance with a circadian rhythm, diurnal fluctuations in Npgl and Npgm mRNA expression were investigated in mice. Quantitative RT-PCR analysis revealed that the mRNAs of these two genes were highly expressed in the mediobasal hypothalamus during the active dark phase under ad libitum feeding. In mice restricted to 3 h of feeding during the inactive light phase, the Npgl mRNA level was augmented in the moment prior to the feeding period and the midnight peak of Npgm mRNA was attenuated. Moreover, the mRNA expression levels of clock genes, feeding regulatory neuropeptides, and lipid metabolic enzymes in the central and peripheral tissues were comparable to those of central Npgl and Npgm. These data suggest that Npgl and Npgm transcription fluctuates daily and likely mediates feeding behavior and/or energy metabolism at an appropriate time according to the meal timing.
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Affiliation(s)
- Atsuki Kadota
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Eiko Iwakoshi-Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Keisuke Fukumura
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Kenshiro Shikano
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
- Department of Neurophysiology, Faculty of Medicine, Oita University, Yufu, Oita 879-5593, Japan
| | - Yuki Narimatsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Megumi Furumitsu
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
| | - Kazuyoshi Ukena
- Laboratory of Neurometabolism, Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8521, Japan; (A.K.); (E.I.-U.); (K.F.); (K.S.); (Y.N.); (M.F.)
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Rosas Fernández MA, Concha Vilca CM, Batista LO, Ramos VW, Cinelli LP, Tibau de Albuquerque K. Intermittent food restriction in female rats induces SREBP high expression in hypothalamus and immediately postfasting hyperphagia. Nutrition 2018; 48:122-126. [DOI: 10.1016/j.nut.2017.11.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 10/16/2017] [Accepted: 11/11/2017] [Indexed: 10/18/2022]
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Swierczynski J, Hebanowska A, Sledzinski T. Role of abnormal lipid metabolism in development, progression, diagnosis and therapy of pancreatic cancer. World J Gastroenterol 2014; 20:2279-303. [PMID: 24605027 PMCID: PMC3942833 DOI: 10.3748/wjg.v20.i9.2279] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/25/2013] [Accepted: 01/03/2014] [Indexed: 02/07/2023] Open
Abstract
There is growing evidence that metabolic alterations play an important role in cancer development and progression. The metabolism of cancer cells is reprogrammed in order to support their rapid proliferation. Elevated fatty acid synthesis is one of the most important aberrations of cancer cell metabolism. An enhancement of fatty acids synthesis is required both for carcinogenesis and cancer cell survival, as inhibition of key lipogenic enzymes slows down the growth of tumor cells and impairs their survival. Based on the data that serum fatty acid synthase (FASN), also known as oncoantigen 519, is elevated in patients with certain types of cancer, its serum level was proposed as a marker of neoplasia. This review aims to demonstrate the changes in lipid metabolism and other metabolic processes associated with lipid metabolism in pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic neoplasm, characterized by high mortality. We also addressed the influence of some oncogenic factors and tumor suppressors on pancreatic cancer cell metabolism. Additionally the review discusses the potential role of elevated lipid synthesis in diagnosis and treatment of pancreatic cancer. In particular, FASN is a viable candidate for indicator of pathologic state, marker of neoplasia, as well as, pharmacological treatment target in pancreatic cancer. Recent research showed that, in addition to lipogenesis, certain cancer cells can use fatty acids from circulation, derived from diet (chylomicrons), synthesized in liver, or released from adipose tissue for their growth. Thus, the interactions between de novo lipogenesis and uptake of fatty acids from circulation by PDAC cells require further investigation.
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MacKay H, Khazall R, Patterson ZR, Wellman M, Abizaid A. Rats perinatally exposed to food restriction and high-fat diet show differences in adipose tissue gene expression under chronic caloric restriction. Adipocyte 2013; 2:237-45. [PMID: 24052899 PMCID: PMC3774699 DOI: 10.4161/adip.24752] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/12/2013] [Accepted: 04/19/2013] [Indexed: 11/24/2022] Open
Abstract
The aim of this study is to analyze how maternal diet during the lactational period influences the adipose tissue response to chronic caloric restriction in offspring. Lactating dams were subjected to one of three treatments: 50% food restriction (FR), ad lib standard chow (AL), or ad lib high-fat diet (HF). Juveniles were first weaned onto standard chow, then in adulthood 50% calorically restricted and maintained at 90% of normal body weight for 60 d. HF animals showed increased percent body fat compared with AL and FR animals despite equivalent body weights. HF animals showed alterations in the balance of adipose tissue lipogenic (FAS, LPL) and lipolytic (HSL) gene expression that may underlie their propensity to maintain fat stores under caloric restriction.
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Karbowska J, Kochan Z. Intermittent fasting up-regulates Fsp27/Cidec gene expression in white adipose tissue. Nutrition 2011; 28:294-9. [PMID: 21996045 DOI: 10.1016/j.nut.2011.06.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Revised: 06/08/2011] [Accepted: 06/28/2011] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Fat-specific protein of 27 kDa (FSP27) is a novel lipid droplet protein that promotes triacylglycerol storage in white adipose tissue (WAT). The regulation of the Fsp27 gene expression in WAT is largely unknown. We investigated the nutritional regulation of FSP27 in WAT. METHODS The effects of intermittent fasting (48 d, eight cycles of 3-d fasting and 3-d refeeding), caloric restriction (48 d), fasting-refeeding (3-d fasting and 3-d refeeding), and fasting (3 d) on mRNA expression of FSP27, peroxisome proliferator-activated receptor γ (PPARγ2), CCAAT/enhancer binding protein α (C/EBPα), and M isoform of carnitine palmitoyltransferase 1 (a positive control for PPARγ activation) in epididymal WAT and on serum triacylglycerol, insulin, and leptin levels were determined in Wistar rats. We also determined the effects of PPARγ activation by rosiglitazone or pioglitazone on FSP27 mRNA levels in primary rat adipocytes. RESULTS Long-term intermittent fasting, in contrast to other dietary manipulations, significantly up-regulated Fsp27 gene expression in WAT. Moreover, in rats subjected to intermittent fasting, serum insulin levels were elevated; PPARγ2 and C/EBPα mRNA expression in WAT was increased, and there was a positive correlation of Fsp27 gene expression with PPARγ2 and C/EBPα mRNA levels. FSP27 mRNA expression was also increased in adipocytes treated with PPARγ agonists. CONCLUSION Our study demonstrates that the transcription of the Fsp27 gene in adipose tissue may be induced in response to nutritional stimuli. Furthermore, PPARγ2, C/EBPα, and insulin may be involved in the nutritional regulation of FSP27. Thus intermittent fasting, despite lower caloric intake, may promote triacylglycerol deposition in WAT by increasing the expression of genes involved in lipid storage, such as Fsp27.
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Affiliation(s)
- Joanna Karbowska
- Department of Biochemistry, Medical University of Gdansk, Gdansk, Poland.
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Montani JP, Viecelli AK, Prévot A, Dulloo AG. Weight cycling during growth and beyond as a risk factor for later cardiovascular diseases: the 'repeated overshoot' theory. Int J Obes (Lond) 2010; 30 Suppl 4:S58-66. [PMID: 17133237 DOI: 10.1038/sj.ijo.0803520] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In people trying to lose weight, there are often repeated cycles of weight loss and regain. Weight cycling is, however, not limited to obese adults but affects people of normal weight, particularly young women, who are unhappy with their appearance. Furthermore, the onset of a pattern of weight cycling is shifting towards younger ages, owing to the increasing prevalence of overweight and obesity in children and adolescents, and the pressure from the media and society for a slim image even for normal weight children. Although there is still controversy whether weight cycling promotes body fat accumulation and obesity, there is mounting evidence from large population studies for increased cardiovascular risks in response to a behavior of weight cycling. Potential mechanisms by which weight cycling contributes to cardiovascular morbidity include hypertension, visceral fat accumulation, changes in adipose tissue fatty acid composition, insulin resistance and dyslipidemia. Moreover, fluctuations in blood pressure, heart rate, sympathetic activity, glomerular filtration rate, blood glucose and lipids that may occur during weight cycling--with overshoots above normal values during weight regain periods--put an additional load on the cardiovascular system, and may be easily overlooked if humans or animals are studied during a state of relatively stable weight. Overshoot of those risks factors, when repeated over time, will stress the cardiovascular system and probably contribute to the overall cardiovascular morbidity of weight cycling.
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Affiliation(s)
- J-P Montani
- Division of Physiology, Department of Medicine, University of Fribourg, Fribourg, Switzerland.
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Nye CK, Hanson RW, Kalhan SC. Glyceroneogenesis is the dominant pathway for triglyceride glycerol synthesis in vivo in the rat. J Biol Chem 2008; 283:27565-27574. [PMID: 18662986 PMCID: PMC2562054 DOI: 10.1074/jbc.m804393200] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 07/22/2008] [Indexed: 12/13/2022] Open
Abstract
Triglyceride synthesis in mammalian tissues requires glycerol 3-phosphate as the source of triglyceride glycerol. In this study the relative contribution of glyceroneogenesis and glycolysis to triglyceride glycerol synthesis was quantified in vivo in adipose tissue, skeletal muscle, and liver of the rat in response to a chow diet (controls), 48-h fast, and lipogenic (high sucrose) diet. The rate of glyceroneogenesis was quantified using the tritium ([(3)H(2)]O) labeling of body water, and the contribution of glucose, via glycolysis, was determined using a [U-(14)C]glucose tracer. In epididymal and mesenteric adipose tissue of control rats, glyceroneogenesis accounted for approximately 90% of triglyceride glycerol synthesis. Fasting for 48 h did not alter glyceroneogenesis in adipose tissue, whereas the contribution of glucose was negligible. In response to sucrose feeding, the synthesis of triglyceride glycerol via both glyceroneogenesis and glycolysis nearly doubled (versus controls); however, glyceroneogenesis remained quantitatively higher as compared with the contribution of glucose. Enhancement of triglyceride-fatty acid cycling by epinephrine infusion resulted in a higher rate of glyceroneogenesis in adipose tissue, as compared with controls, whereas the contribution of glucose via glycolysis was not measurable. Glyceroneogenesis provided the majority of triglyceride glycerol in the gastrocnemius and soleus. In the liver the fractional contribution of glyceroneogenesis remained constant (approximately 60%) under all conditions and was higher than that of glucose. Thus, glyceroneogenesis, in contrast to glucose, via glycolysis, is quantitatively the predominant source of triglyceride glycerol in adipose tissue, skeletal muscle, and liver of the rat during fasting and high sucrose feeding.
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Affiliation(s)
- Colleen K Nye
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106; Departments of Gastroenterology and Pathobiology, Cleveland Clinic, Cleveland, Ohio 44195
| | - Richard W Hanson
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106; Departments of Gastroenterology and Pathobiology, Cleveland Clinic, Cleveland, Ohio 44195
| | - Satish C Kalhan
- Departments of Gastroenterology and Pathobiology, Cleveland Clinic, Cleveland, Ohio 44195; Department of Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland Clinic, Cleveland, Ohio 44195.
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Sakurai T, Takei M, Ogasawara J, Ueda H, Kizaki T, Ohno H, Izawa T. Exercise before or after refeeding prevents refeeding-induced recovery of cell size after fasting with a different pattern of metabolic gene expressions in rat epididymal adipocytes. Metabolism 2007; 56:1270-8. [PMID: 17697872 DOI: 10.1016/j.metabol.2007.05.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2006] [Accepted: 05/15/2007] [Indexed: 11/25/2022]
Abstract
We investigated the effect of exercise before or after refeeding on cell size and on the expression of several messenger RNAs (mRNAs) involved in lipolysis and lipogenesis in fasted rat epididymal adipocytes. Fasting for 65 hours reduced the diameter of adipocytes to 72.0 microm from 78.4 microm in fed control rats, whereas refeeding for 1 or 2 days restored adipocyte size to 74.0 or 75.8 microm, respectively. Exercise before or after refeeding blocked refeeding-induced restoration of adipocyte size and led to adipocyte size similar to that observed after fasting. Fasting dramatically reduced expression of the fatty acid synthase mRNA, although expression of this gene returned to the control level after refeeding. However, exercise after but not before refeeding inhibited recovery of the expression of fatty acid synthase mRNA resulting from refeeding. In contrast, exercise before but not after refeeding led to enhanced expression of mRNAs encoding the hormone-sensitive lipase and beta(3)-aderenoceptor. Thus, exercise before or after refeeding prevents refeeding-induced restoration of adipocyte size after fasting via different pathways. Exercise before and after refeeding enhanced the expression of lipolytic mRNAs or inhibited the expression of lipogenic mRNAs, respectively.
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Affiliation(s)
- Takuya Sakurai
- Department of Kinesiology, Graduate School of Science, Tokyo Metropolitan University, Tokyo, Japan
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Bertile F, Raclot T. mRNA levels of SREBP-1c do not coincide with the changes in adipose lipogenic gene expression. Biochem Biophys Res Commun 2005; 325:827-34. [PMID: 15541365 DOI: 10.1016/j.bbrc.2004.10.110] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Indexed: 11/23/2022]
Abstract
Physiological differences in lipid metabolism exist according to adipose sites. To delineate at which step such gene regulation could occur, mRNA levels of various proteins involved in the overall lipogenic process were determined in subcutaneous (SC) and retroperitoneal (RP) adipose tissues. Fatty acid synthase, malic enzyme, ATP citrate lyase, insulin-sensitive glucose transporter, and glucose-6-phosphate dehydrogenase mRNA levels were coordinately reduced (by up to 50-fold) during fasting in RP and in SC relative to fed rats, and restored or overexpressed (by up to 5- to 6-fold) during refeeding. The response was most often delayed and lower in SC compared to RP. This could contribute to site-specific differences. Interestingly, SREBP-1c mRNA levels were markedly decreased by fasting in SC but remained unchanged in RP. Refeeding tended to restore levels close to fed group values. We conclude that mRNA levels of SREBP-1c do not coincide with the expected changes in adipose lipogenic gene expression of fasted/refed rats.
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Affiliation(s)
- Fabrice Bertile
- Centre d'Ecologie et Physiologie Energétiques, UPR 9010 CNRS, associé à l'Université Louis Pasteur, 23 rue Becquerel, 67087 Strasbourg Cedex 2, France.
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Kochan Z, Karbowska J. Dehydroepiandrosterone up-regulates resistin gene expression in white adipose tissue. Mol Cell Endocrinol 2004; 218:57-64. [PMID: 15130511 DOI: 10.1016/j.mce.2003.12.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2003] [Revised: 11/12/2003] [Accepted: 12/22/2003] [Indexed: 11/27/2022]
Abstract
Dehydroepiandrosterone (DHEA), the most abundant steroid hormone in human blood, is considered to be one of fat-reducing hormones. However, the molecular mechanisms underlying DHEA mode of action in obesity has not been fully clarified. The pivotal role in the maintenance of cellular lipid and energy balance is played by peroxisome proliferator-activated receptor alpha (PPARalpha) which acts as transcriptional activator of numerous genes encoding enzymes involved in fatty acid catabolism. Lately published papers suggest that resistin, a low molecular-weight protein produced by adipose tissue, may act as an inhibitor of adipocyte differentiation and could regulate adipose tissue mass. Recent studies have established that the promoter region of the resistin gene contains several putative PPAR response elements. Since DHEA has been characterized as a peroxisome proliferator able to induce hepatic genes through PPARalpha, we hypothesised that DHEA might affect PPARalpha and, subsequently, resistin gene expression in adipose tissue. In order to test this hypothesis, an experiment was performed comparing PPARalpha and resistin gene expression in white adipose tissue (WAT) of male Wistar rats fed standard or DHEA-supplemented (0.6% (w/w)) diet for 2 weeks. DHEA administration to the rats induced PPARalpha and resistin gene expression in WAT (3- and 2.25-fold, respectively; as determined by real-time reverse transcription-polymerase chain reaction (RT-PCR)); reduced body weight, epididymal adipose tissue mass and decreased serum leptin levels. We propose that DHEA may impact on the transcription of resistin gene through a mechanism involving PPARalpha and that an elevated resistin level may lead to an inhibition of adipogenesis and a decrease in adipose tissue mass.
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Affiliation(s)
- Zdzislaw Kochan
- Department of Biochemistry, Medical University of Gdansk, Debinki 1, 80-211 Gdansk, Poland.
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Minehira K, Bettschart V, Vidal H, Vega N, Di Vetta V, Rey V, Schneiter P, Tappy L. Effect of carbohydrate overfeeding on whole body and adipose tissue metabolism in humans. OBESITY RESEARCH 2003; 11:1096-103. [PMID: 12972680 DOI: 10.1038/oby.2003.150] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To evaluate the effect of a 4-day carbohydrate overfeeding on whole body net de novo lipogenesis and on markers of de novo lipogenesis in subcutaneous adipose tissue of healthy lean humans. RESEARCH METHODS AND PROCEDURES Nine healthy lean volunteers (five men and four women) were studied after 4 days of either isocaloric feeding or carbohydrate overfeeding. On each occasion, they underwent a metabolic study during which their energy expenditure and net substrate oxidation rates (indirect calorimetry), and the fractional activity of the pentose-phosphate pathway in subcutaneous adipose tissue (subcutaneous microdialysis with 1,6(13)C2,6,6(2)H2 glucose) were assessed before and after administration of glucose. Adipose tissue biopsies were obtained at the end of the experiments to monitor mRNAs of key lipogenic enzymes. RESULTS Carbohydrate overfeeding increased basal and postglucose energy expenditure and net carbohydrate oxidation. Whole body net de novo lipogenesis after glucose loading was markedly increased at the expense of glycogen synthesis. Carbohydrate overfeeding also increased mRNA levels for the key lipogenic enzymes sterol regulatory element-binding protein-1c, acetyl-CoA carboxylase, and fatty acid synthase. The fractional activity of adipose tissue pentose-phosphate pathway was 17% to 22% and was not altered by carbohydrate overfeeding. DISCUSSION Carbohydrate overfeeding markedly increased net de novo lipogenesis at the expense of glycogen synthesis. An increase in mRNAs coding for key lipogenic enzymes suggests that de novo lipogenesis occurred, at least in part, in adipose tissue. The pentose-phosphate pathway is active in adipose tissue of healthy humans, consistent with an active role of this tissue in de novo lipogenesis.
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Affiliation(s)
- Kaori Minehira
- Institute of Physiology, University of Lausanne, Lausanne, Switzerland
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