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Oliveira THCD, Gonçalves GKN. Effect of ovariectomy and high-fat diet on the expression of estrogen receptors and adipose tissue metabolism in wistar rats. Mol Cell Endocrinol 2024; 592:112327. [PMID: 38996834 DOI: 10.1016/j.mce.2024.112327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 07/05/2024] [Accepted: 07/06/2024] [Indexed: 07/14/2024]
Abstract
This study addresses the increasing prevalence of obesity, especially among postmenopausal. Estrogen plays a crucial role in regulating adipose tissue in women, with its absence after menopause associated with metabolic complications. The study aimed to determine the lipolytic activity in different adipose tissue depots of ovariectomized rats submitted to a high-fat diet. Also, to analyze the expression of estrogen receptors in adipose tissues and perform histological and morphometric analyzes of these deposits. Female rats were ovariectomized (O) or sham operated (S). The animals were divided into groups: ovariectomized with high-fat diet (OF), sham-operated with high-fat diet (SF), ovariectomized with control diet (OC) or sham-operated with control diet as the control group (SC). After 24 weeks of consuming the diets, rats were killed and adipose tissue deposits were removed. Polymerase chain reaction was performed to analyze the expression of estrogen receptors in adipose tissues, lipolysis assay and histological analysis. Both the high-fat diet and ovariectomy increased body weight and adiposity. There was hypertrophy of adipocytes. Estrogen replacement therapy modulate lipolytic activity in different adipose depots, with different responses in relation to estrogen receptors. Estrogen receptor expression varied between fat depots. Mesenteric adipose tissue showed greater sensitivity to estrogen compared with others. Estrogen increased lipolytic activity in some fat depots, reducing in others. Expression of ERs depends of hormonal status and adipose tissue location, which may explain distinct actions of estrogen on the metabolism of adipose tissue and on the production of adipokines by them.
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Barrea L, Verde L, Auriemma RS, Vetrani C, Cataldi M, Frias-Toral E, Pugliese G, Camajani E, Savastano S, Colao A, Muscogiuri G. Probiotics and Prebiotics: Any Role in Menopause-Related Diseases? Curr Nutr Rep 2023; 12:83-97. [PMID: 36746877 PMCID: PMC9974675 DOI: 10.1007/s13668-023-00462-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2023] [Indexed: 02/08/2023]
Abstract
PURPOSE OF REVIEW The aim of this review is to provide an overview of the menopause-related changes in microbiota and their role in the pathogenesis of menopause-related diseases. In addition, evidence on probiotic supplementation as a therapeutic strategy is discussed. RECENT FINDINGS The human microbiota is a complex community that lives in a mutualism relationship with the host. Menopause is associated with dysbiosis, and these changes in the composition of microbiota in different sites (gut, vaginal, and oral microbiota) might play a role in the pathogenesis of menopause-related diseases (i.e., osteoporosis, breast cancer, endometrial hyperplasia, periodontitis, and cardiometabolic diseases). The present review highlights the pivotal role of microbiota in postmenopausal women health, in particular it (a) may increase intestinal calcium absorption thus preventing osteoporosis, (b) is associated with reduced risk of breast cancer and type 1 endometrial hyperplasia, (c) reduces gingival inflammation and menopausal periodontitis, and (d) beneficially affects multiple cardiometabolic risk factors (i.e., obesity, inflammation, and blood glucose and lipid metabolism). However, whether oral probiotic supplementation might be used for the treatment of menopause-related dysbiosis requires further clarification.
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Affiliation(s)
- Luigi Barrea
- Dipartimento di Scienze Umanistiche, Centro Direzionale, Università Telematica Pegaso, Via Porzio, isola F2, 80143, Naples, Italy
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
| | - Ludovica Verde
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy.
- Department of Public Health, University of Naples Federico II, Naples, Italy.
| | - Renata Simona Auriemma
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
| | - Claudia Vetrani
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
| | - Mauro Cataldi
- Section of Pharmacology, Department of Neuroscience, School of Medicine, University of Naples Federico II, Naples, Italy
| | - Evelyn Frias-Toral
- Universidad Católica Santiago de Guayaquil, Av. Pdte. Carlos Julio Arosemena Tola, Guayaquil, 090615, Ecuador
| | - Gabriella Pugliese
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
| | - Elisabetta Camajani
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Roma Open University, 00166, Rome, Italy
| | - Silvia Savastano
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
| | - Annamaria Colao
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
- Cattedra Unesco "Educazione alla salute e allo sviluppo sostenibile", University Federico II, Naples, Italy
| | - Giovanna Muscogiuri
- Centro Italiano per la cura e il Benessere del Paziente con Obesità (C.I.B.O), Department of Clinical Medicine and Surgery, Endocrinology Unit, University Medical School of Naples, Via Sergio Pansini 5, 80131, Naples, Italy
- Dipartimento di Medicina Clinica e Chirurgia, Unità di Endocrinologia, Diabetologia e Andrologia, Università degli Studi di Napoli Federico II, Via Sergio Pansini 5, Naples, 80131, Italy
- Cattedra Unesco "Educazione alla salute e allo sviluppo sostenibile", University Federico II, Naples, Italy
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Martinez-Pena Y Valenzuela I, Akaaboune M. The disassembly of the neuromuscular synapse in high-fat diet-induced obese male mice. Mol Metab 2020; 36:100979. [PMID: 32283080 PMCID: PMC7182767 DOI: 10.1016/j.molmet.2020.100979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/09/2020] [Accepted: 03/10/2020] [Indexed: 12/16/2022] Open
Abstract
Objective A sustained high fat diet in mice mimics many features of human obesity. We used male and female Non-Swiss albino mice to investigate the impact of short and long-term high-fat diet-(HFD)-induced obesity on the peripheral neuromuscular junction (NMJ) and whether obesity-related synaptic structural alterations were reversible after switching obese mice from HFD to a standard fat diet (SD). Methods HFD-induced obese and age-matched control mice fed SD were used. We carried out in vivo time lapse imaging to monitor changes of synapses over time, quantitative fluorescence imaging to study the regulation of acetylcholine receptor number and density at neuromuscular junctions, and high resolution confocal microscope to study structural alterations in both the pre- and postsynaptic apparatus. Results Time-lapse imaging in vivo over a 9 month period revealed that NMJs of HFD obese male mice display a variety of obesity-related structural alterations, including the disappearance of large synaptic areas, significant reduction in the density/number of nicotinic acetylcholine receptor (AChRs), abnormal distribution of AChRs, high turnover rate of AChRs, retraction of axons from lost postsynaptic sites, and partially denervated synapses. The severity of these synaptic alterations is associated with the duration of obesity. However, no substantial alterations were observed at NMJs of age-matched HFD obese female mice or male mice fed with a standard or low fat diet. Intriguingly, when obese male mice were switched from HFD to a standard diet, receptor density and the abnormal pattern of AChR distribution were completely reversed to normal, whereas lost synaptic structures were not restored. Conclusions These results show that the obese male mice are more vulnerable than female mice to the impacts of long-term HFD on the NMJ damage and provide evidence that diet restriction can partially reverse obesity-related synaptic changes. Neuromuscular junctions of High-fat induced obese male mice display a variety of obesity-related structural alterations. The severity of alterations in neuromuscular junction morphology is associated with the duration of obesity. Neuromuscular junctions of High-fat diet induced obese female mice display no substantial morphological changes. Not all obesity-related synaptic alterations were reversible after switching male mice from High-fat diet to standard diet. Obese male mice are more vulnerable than female mice to the impacts of long-term HFD on the neuromuscular junction damage.
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Affiliation(s)
| | - Mohammed Akaaboune
- Department of Molecular, Cellular, and Developmental Biology, USA; Program in Neuroscience, University of Michigan, Ann Arbor, MI, 48109, USA.
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Frank AP, de Souza Santos R, Palmer BF, Clegg DJ. Determinants of body fat distribution in humans may provide insight about obesity-related health risks. J Lipid Res 2018; 60:1710-1719. [PMID: 30097511 DOI: 10.1194/jlr.r086975] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/07/2018] [Indexed: 12/24/2022] Open
Abstract
Obesity increases the risks of developing cardiovascular and metabolic diseases and degrades quality of life, ultimately increasing the risk of death. However, not all forms of obesity are equally dangerous: some individuals, despite higher percentages of body fat, are at less risk for certain chronic obesity-related complications. Many open questions remain about why this occurs. Data suggest that the physical location of fat and the overall health of fat dramatically influence disease risk; for example, higher concentrations of visceral relative to subcutaneous adipose tissue are associated with greater metabolic risks. As such, understanding the determinants of the location and health of adipose tissue can provide insight about the pathological consequences of obesity and can begin to outline targets for novel therapeutic approaches to combat the obesity epidemic. Although age and sex hormones clearly play roles in fat distribution and location, much remains unknown about gene regulation at the level of adipose tissue or how genetic variants regulate fat distribution. In this review, we discuss what is known about the determinants of body fat distribution, and we highlight the important roles of sex hormones, aging, and genetic variation in the determination of body fat distribution and its contribution to obesity-related comorbidities.
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Affiliation(s)
- Aaron P Frank
- Diabetes, Obesity, and Wellness Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Roberta de Souza Santos
- Diabetes, Obesity, and Wellness Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Biff F Palmer
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Deborah J Clegg
- Diabetes, Obesity, and Wellness Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA
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MacDonald TL, MacPherson R, Castellani L, Cervone D, Anderson E, Wright DC, Dyck DJ. Estradiol does not directly regulate adipose lipolysis. Adipocyte 2017; 6:76-86. [PMID: 28425842 DOI: 10.1080/21623945.2017.1287638] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The mechanisms by which estradiol modulates adipose lipolysis are poorly understood. We sought to measure basal and β3-stimulated indices of lipoysis (FFAs, glycerol) in vivo in E2 deficient or supplemented rats, and ex vivo with direct acute E2 exposure. For 2 weeks, ovariectomized (OVX) and OVX rats treated with a daily oral dose of E2 (OVX E2) were pairfed to SHAM controls (n = 12 per group). Adipocyte size was modestly (∼40%) increased in OVX rats, but did not reach significance (p = 0.2). After 2 weeks, half of the animals in each group received an in vivo injection of saline or 1 mg/kg of the β3 agonist CL 316, 243. Serum FFA concentrations, but not glycerol, were lower in OVX and OVX E2 rats compared with SHAM controls (p = 0.02). A significant CL response was present in all groups (p<0.001) and HSL activation was unaffected by OVX or OVX E2 in retroperitoneal (r.p.) or inguinal (iWAT) adipose depots in vivo. Ex vivo, CL increased FFA and glycerol accumulation in the media as well as HSL phosphorylation by several fold in r.p. and iWAT explants, but responses from OVX and OVX E2 rats were comparable to SHAMs. To assess whether E2 can directly affect lipolysis, r.p. and iWAT tissue was treated with E2, CL or E2 + CL for 2, 4 or 8 hours using adipose tissue organ culture. CL stimulated FFA release (p<0.001), but was unaffected by E2. Overall, our results indicate that E2 does not directly regulate adipose tissue lipolysis.
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Affiliation(s)
- Tara L. MacDonald
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Rebecca MacPherson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Laura Castellani
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Daniel Cervone
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Eoin Anderson
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - David C. Wright
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - David J. Dyck
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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Cox-York KA, Erickson CB, Pereira RI, Bessesen DH, Van Pelt RE. Region-specific effects of oestradiol on adipose-derived stem cell differentiation in post-menopausal women. J Cell Mol Med 2016; 21:677-684. [PMID: 27862950 PMCID: PMC5345675 DOI: 10.1111/jcmm.13011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 09/18/2016] [Indexed: 12/25/2022] Open
Abstract
The goal of this study was to determine the effect of acute transdermal 17β‐oestradiol (E2) on the adipogenic potential of subcutaneous adipose‐derived stem cells (ASC) in post‐menopausal women. Post‐menopausal women (n = 11; mean age 57 ± 4.5 years) were treated for 2 weeks, in a randomized, cross‐over design, with transdermal E2 (0.15 mg) or placebo patches. Biopsies of abdominal (AB) and femoral (FEM) subcutaneous adipose tissue (SAT) were obtained after each treatment and mature adipocytes were analysed for cell size and ASC for their capacity for proliferation (growth rate), differentiation (triglyceride accumulation) and susceptibility to tumour necrosis factor alpha‐induced apoptosis. Gene expression of oestrogen receptors α and β (ESR1 and ESR2), perilipin 1 and hormone‐sensitive lipase (HSL), was also assessed. In FEM SAT, but not AB SAT, 2 weeks of E2 significantly (P = 0.03) increased ASC differentiation and whole SAT HSL mRNA expression (P = 0.03) compared to placebo. These changes were not associated with mRNA expression of oestrogen receptors α and β, but HSL expression was significantly increased in FEM SAT with transdermal E2 treatment. Adipose‐derived stem cells proliferation and apoptosis did not change in either SAT depot after E2 compared with placebo. Short‐term E2 appeared to increase the adipogenic potential of FEM, but not AB, SAT in post‐menopausal women with possible implications for metabolic disease. Future studies are needed to determine longer term impact of E2 on regional SAT accumulation in the context of positive energy imbalance.
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Affiliation(s)
| | - Christopher B Erickson
- Department of Medicine, Division of Geriatric Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Rocio I Pereira
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Denver Health and Hospital Authority, Denver, CO, USA
| | - Daniel H Bessesen
- Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.,Denver Health and Hospital Authority, Denver, CO, USA
| | - Rachael E Van Pelt
- Department of Medicine, Division of Geriatric Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
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Karvonen-Gutierrez C, Kim C. Association of Mid-Life Changes in Body Size, Body Composition and Obesity Status with the Menopausal Transition. Healthcare (Basel) 2016; 4:healthcare4030042. [PMID: 27417630 PMCID: PMC5041043 DOI: 10.3390/healthcare4030042] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/29/2016] [Accepted: 07/08/2016] [Indexed: 12/16/2022] Open
Abstract
The mid-life period is a critical window for increases in body weight and changes in body composition. In this review, we summarize the clinical experience of the menopausal transition by obesity status, and examine the evidence regarding the menopausal transition and reproductive hormones effects on body weight, body composition, or fat distribution. Mid-life obesity is associated with a different menopausal experience including associations with menstrual cycle length prior to the final menstrual period (FMP), age at the FMP, and higher prevalence of vasomotor symptoms. The menopausal transition is associated with weight gain and increased central body fat distribution; the majority of evidence suggests that changes in weight are due to chronological aging whereas changes in body composition and fat distribution are primarily due to ovarian aging. Continuous and regular physical activity during mid-life may be an efficacious strategy to counteract the age-related and menopause-related changes in resting energy expenditure and to prevent weight gain and abdominal adiposity deposition.
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Affiliation(s)
- Carrie Karvonen-Gutierrez
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Catherine Kim
- Departments of Medicine and Obstetrics & Gynecology, University of Michigan, Ann Arbor, MI 48109, USA.
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Bispo K, Amusquivar E, García-Seco D, Ramos-Solano B, Gutierrez-Mañero J, Herrera E. Supplementing diet with blackberry extract causes a catabolic response with increments in insulin sensitivity in rats. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 2015; 70:170-175. [PMID: 25724576 DOI: 10.1007/s11130-015-0474-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Blackberry (Rubus sp.) fruit has a high content of anthocyanins, but its health benefits have not been sufficiently explored in healthy individuals. Thus, the aim of the study was to determine the effects of blackberry extract on lipid and glucose variables in female and male rats. Sprague Dawley rats were given a standard pellet (SD) or cafeteria (CD) diet supplemented (SD+R and CD+R) or not with Rubus extract for 80 days. Female rats given SD+R had lower body and liver weights than SD females; both sexes given SD+R showed lower plasma glucose and insulin, higher plasma NEFA, glycerol and 3-hydroxybutyrate, and higher liver concentration of triacylglycerols than SD rats. The homeostasis model of insulin resistance (HOMA) was lower in SD+R rats than in SD rats, but higher in CD rats. No effects of Rubus extract were observed in CD rats. In conclusion, Rubus extract, in rats given SD, decreased glycemia and increased insulin sensitivity. It also increased lipid breakdown in adipose tissue. The effects were greater in females than in males. No effect was seen in rats given CD, probably as a result of their high insulin resistance.
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Affiliation(s)
- Kenia Bispo
- Faculty of Pharmacy, Universidad San Pablo CEU, Ctra. Boadilla del Monte km 5.3, 28668, Madrid, Spain
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Sarr O, Thompson JA, Zhao L, Lee TY, Regnault TRH. Low birth weight male guinea pig offspring display increased visceral adiposity in early adulthood. PLoS One 2014; 9:e98433. [PMID: 24926663 PMCID: PMC4057084 DOI: 10.1371/journal.pone.0098433] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 05/03/2014] [Indexed: 12/25/2022] Open
Abstract
Uteroplacental insufficiency (UPI)-induced intrauterine growth restriction (IUGR) predisposes individuals to adult visceral obesity. We postulated that low birth weight (LBW) offspring, from UPI-induced IUGR pregnancies, would display a visceral adipose lipogenic molecular signature involving altered gene expression, phosphorylation status of proteins of the lipid synthesis pathway and microRNA (miR) expression profile, occurring in association with increased visceral adiposity. Normal birth weight (NBW) and LBW (obtained by uterine artery ablation) male guinea pig pups were fed a control diet from weaning to 145 days and sacrificed. Despite being lighter at birth, LBW pups displayed body weights similar to NBW offspring at 145 days. At this age, which represents young adulthood, the relative weights of LBW epididymal white adipose tissue (EWAT) and lipid content were increased; which was consistent with adipocyte hypertrophy in the LBW offspring. Additionally, the mRNA expression of lipid synthesis-related genes including acetyl-CoA carboxylase 1 (ACC1), diglyceride acyltransferase 2 (DGAT2) and peroxisome proliferator-activated receptor gamma 1 (PPARγ1), was increased in LBW EWAT. Further, LBW EWAT displayed decreased phospho-ACC (Ser79) and phospho-PPARγ (Ser273) proteins. Moreover, the mRNA expression of hormone-sensitive lipase (HSL) and fatty acid binding protein 4 (FABP4), both involved in promoting adipose lipid storage, was increased in LBW EWAT. Finally, miR-24 and miR-103-2, miRs related to adipocyte development, were both increased in LBW EWAT. These findings indicate that, following an adverse in utero environment, lipid synthesis-related genes and miR expression, along with phosphorylation status of key regulators of lipid synthesis, appear to be chronically altered and occur in association with increased visceral adiposity in young adult IUGR male offspring.
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Affiliation(s)
- Ousseynou Sarr
- Department of Obstetrics and Gynecology, Children's Health Research Institute, Lawson Health Research Institute, Western University, London, Ontario, Canada
- * E-mail:
| | - Jennifer A. Thompson
- Department of Physiology, Georgia Regents University, Augusta, Georgia, United States of America
| | - Lin Zhao
- Department of Obstetrics and Gynecology, Children's Health Research Institute, Lawson Health Research Institute, Western University, London, Ontario, Canada
| | - Ting-Yim Lee
- Departments of Medical Imaging, Medical Biophysics, and Oncology, Western University, London, Ontario, Canada
- Lawson Imaging, Lawson Health Research Institute, London, Ontario, Canada
- Robarts Research Institute, London, Ontario, Canada
| | - Timothy R. H. Regnault
- Department of Obstetrics and Gynecology, Children's Health Research Institute, Lawson Health Research Institute, Western University, London, Ontario, Canada
- Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
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Varlamov O, Chu MP, McGee WK, Cameron JL, O'Rourke RW, Meyer KA, Bishop CV, Stouffer RL, Roberts CT. Ovarian cycle-specific regulation of adipose tissue lipid storage by testosterone in female nonhuman primates. Endocrinology 2013; 154:4126-35. [PMID: 24008344 PMCID: PMC3800767 DOI: 10.1210/en.2013-1428] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previous studies in rodents and humans suggest that hyperandrogenemia causes white adipose tissue (WAT) dysfunction in females, although the underlying mechanisms are poorly understood. In light of the differences in the length of the ovarian cycle between humans and rodents, we used a nonhuman primate model to elucidate the effects of chronic hyperandrogenemia on WAT function in vivo. Female rhesus macaques implanted with testosterone capsules developed insulin resistance and altered leptin secretion on a high-fat, Western-style diet. In control visceral WAT, lipolysis and hormone-sensitive lipase expression were upregulated during the luteal phase compared with the early follicular (menses) phase of the ovarian cycle. Hyperandrogenemia attenuated elevated lipolysis and hormone-sensitive lipase activity in visceral WAT during the luteal phase but not during menses. Under control conditions, insulin-stimulated Akt and Erk activation and fatty acid uptake in WAT were not significantly affected by the ovarian cycle. In contrast, testosterone treatment preferentially increased fatty acid uptake and insulin signaling at menses. The fatty acid synthase and glucose transporter-4 genes were upregulated by testosterone during the luteal phase. In summary, this study reveals ovarian stage-specific fluctuations in adipocyte lipolysis and suggests that male sex hormones increase and female sex hormones decrease lipid storage in female WAT.
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Affiliation(s)
- Oleg Varlamov
- Jr, Oregon National Primate Research Center, 505 NW 185th Avenue, Beaverton, Oregon 97006.
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Endlich PW, Claudio ERG, da Silva Gonçalves WL, Gouvêa SA, Moysés MR, de Abreu GR. Swimming training prevents fat deposition and decreases angiotensin II-induced coronary vasoconstriction in ovariectomized rats. Peptides 2013; 47:29-35. [PMID: 23792185 DOI: 10.1016/j.peptides.2013.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 05/31/2013] [Accepted: 06/03/2013] [Indexed: 11/20/2022]
Abstract
We investigated the effects of chronic swimming training (ST) on the deposition of abdominal fat and vasoconstriction in response to angiotensin II (ANG II) in the coronary arterial bed of estrogen deficient rats. Twenty-eight 3-month old Wistar female rats were divided into 4 groups: sedentary sham (SS), sedentary-ovariectomized (SO), swimming-trained sham (STS) and swimming-trained ovariectomized (STO). ST protocol consisted of a continuous 60-min session, with a 5% BW load attached to the tail, completed 5 days/week for 8-weeks. The retroperitoneal, parametrial, perirenal and inguinal fat pads were measured. The intrinsic heart rate (IHR), coronary perfusion pressure (CPP) and a concentration-response curve to ANG II in the coronary bed was constructed using the Langendorff preparation. Ovariectomy (OVX) significantly reduced 17-β-estradiol plasma levels in SO and STO groups (p<0.05). The STO group had a significantly reduced retroperitoneal and parametrial fat pad compared with the SO group (p<0.05). IHR values were similar in all groups; however, baseline CPP was significantly reduced in the SO, STS and STO groups compared with the SS group (p<0.05). ANG II caused vasoconstriction in the coronary bed in a concentration-dependent manner. The SO group had an increased response to ANG II when compared with all other experimental groups (p<0.05), which was prevented by 8-weeks of ST in the STO group (p<0.05). OVX increased ANG II-induced vasoconstriction in the coronary vascular bed and abdominal fat pad deposition. Eight weeks of swimming training improved these vasoconstrictor effects and decreased abdominal fat deposition in ovariectomized rats.
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Affiliation(s)
- Patrick Wander Endlich
- Department of Physiological Sciences, Health Sciences Center, Federal University of the Espírito Santo, Vitória, Espírito Santo, Brazil.
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Choi JS, Koh IU, Song J. Genistein reduced insulin resistance index through modulating lipid metabolism in ovariectomized rats. Nutr Res 2012; 32:844-55. [PMID: 23176795 DOI: 10.1016/j.nutres.2012.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 09/28/2012] [Accepted: 10/01/2012] [Indexed: 11/16/2022]
Abstract
Postmenopausal women are at higher risk for obesity and insulin resistance due to the decline of estrogen, but genistein, a phytoestrogen, may reduce the risks of these diet-related diseases. In this study, we hypothesized that supplemental genistein has beneficial effects on insulin resistance in an ovariectomized rat model by modulating lipid metabolism. Three weeks after a sham surgery (sham) or an ovariectomy (OVX), ovariectomized Sprague-Dawley rats were placed on a diet containing 0 (OVX group) or 0.1% genistein for 4 weeks. The sham rats were fed a high-fat diet containing 0% genistein and served as the control group (sham group). The ovariectomized rats showed increases in body weight and insulin resistance index, but genistein reduced insulin resistance index and the activity of hepatic fatty acid synthetase. Genistein was also associated with increased activity of succinate dehydrogenase and carnitine palmitoyltransferase and the rate of β-oxidation in the fat tissue of rats. The ovariectomized rats given genistein had smaller-sized adipocytes. Using gene-set enrichment analysis (GSEA) of microarray data, we found that a number of gene sets of fatty acid metabolism, insulin resistance, and oxidative stress were differentially expressed by OVX and reversed by genistein. This systemic approach of GSEA enables the identification of such consensus between the gene expression changes and phenotypic changes caused by OVX and genistein supplementation. Genistein treatment could help reduce insulin resistance through the amelioration of OVX-induced metabolic dysfunction, and the GSEA approach may be useful in proposing putative targets related to insulin resistance.
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Affiliation(s)
- Joo Sun Choi
- Division of Metabolic Disease, Center for Biomedical Sciencope, Korea National Institutes of Health, Chungcheongbuk-do, South Korea
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13
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Abeles EDG, Cordeiro LMDS, Martins ADS, Pesquero JL, Reis AMD, Andrade SP, Botion LM. Estrogen therapy attenuates adiposity markers in spontaneously hypertensive rats. Metabolism 2012; 61:1100-7. [PMID: 22386939 DOI: 10.1016/j.metabol.2011.12.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 12/13/2011] [Accepted: 12/29/2011] [Indexed: 10/28/2022]
Abstract
Ovarian hormones modulate the metabolism of adipose cells and present a protective effect against hypertension. The aim of this study was to compare the effect of estradiol on adiposity markers in spontaneously hypertensive rats. Ovariectomized spontaneously hypertensive rats treated with estradiol (5 μg/100 g/day), three weeks after ovariectomy, presented decreased blood pressure and insulin levels and increased hepatic glycogen content. Periuterine or mesenteric adipocytes from treated animals were smaller as compared to vehicle treated group, whereas no differences were observed in relation to the number of cells. Basal rates of glycerol release were higher only in periuterine adipocytes of treated rats. The increment of glycerol release over basal values in response to isoproterenol was 400% and 440%, 283% and 330% for vehicle and estradiol treated periuterine and mesenteric adipocytes, respectively. The estradiol treated group was more sensitive to insulin inhibition of isoproterenol-stimulated lipolysis than the control animals. The lipoprotein lipase activity decreased after treatment, only in periuterine adipose tissue. Estradiol administration increased basal and insulin-stimulated rates of glucose transport in adipocytes of both sites, although the values obtained by periuterine were higher than those observed for mesenteric adipocytes. Both adipose tissues from treated animals exhibited a decreased expression of the peroxisome proliferator-activated receptor-γ, but an increased expression of peroxisome proliferator-activated receptor-α in liver. These findings suggest that estrogen administration attenuates adiposity markers of spontaneously hypertensive rats as a result of the decreased expression levels of peroxisome proliferator-activated receptor-γ in adipose tissue and increased expression of peroxisome proliferator-activated receptor-α in liver.
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Affiliation(s)
- Eva das Graças Abeles
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
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14
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Abstract
One segment of the population that is particularly inclined to liver fat accumulation is postmenopausal women. Although nonalcoholic hepatic steatosis is more common in men than in women, after menopause there is a reversal in gender distribution. At the present time, weight loss and exercise are regarded as first line treatments for NAFLD in postmenopausal women, as it is the case for the management of metabolic syndrome. In recent years, there has been substantial evidence coming mostly from the use of the animal model, that indeed estrogens withdrawal is associated with modifications of molecular markers favouring the activity of metabolic pathways ultimately leading to liver fat accumulation. In addition, the use of the animal model has provided physiological and molecular evidence that exercise training provides estrogens-like protective effects on liver fat accumulation and its consequences. The purpose of the present paper is to present information relative to the development of a state of NAFLD resulting from the absence of estrogens and the role of exercise training, emphasizing on the contribution of the animal model on these issues.
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15
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NAFLD, Estrogens, and Physical Exercise: The Animal Model. J Nutr Metab 2011; 2012:914938. [PMID: 21845221 PMCID: PMC3154523 DOI: 10.1155/2012/914938] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 06/05/2011] [Indexed: 12/17/2022] Open
Abstract
One segment of the population that is particularly inclined to liver fat accumulation is postmenopausal women. Although nonalcoholic hepatic steatosis is more common in men than in women, after menopause there is a reversal in gender distribution. At the present time, weight loss and exercise are regarded as first line treatments for NAFLD in postmenopausal women, as it is the case for the management of metabolic syndrome. In recent years, there has been substantial evidence coming mostly from the use of the animal model, that indeed estrogens withdrawal is associated with modifications of molecular markers favouring the activity of metabolic pathways ultimately leading to liver fat accumulation. In addition, the use of the animal model has provided physiological and molecular evidence that exercise training provides estrogens-like protective effects on liver fat accumulation and its consequences. The purpose of the present paper is to present information relative to the development of a state of NAFLD resulting from the absence of estrogens and the role of exercise training, emphasizing on the contribution of the animal model on these issues.
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16
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Rachoń D, Vortherms T, Seidlová-Wuttke D, Wuttke W. Effects of dietary equol on body weight gain, intra-abdominal fat accumulation, plasma lipids, and glucose tolerance in ovariectomized Sprague-Dawley rats. Menopause 2007; 14:925-32. [PMID: 17414092 DOI: 10.1097/gme.0b013e31802d979b] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To evaluate the effects of dietary equol, a metabolite of the phytoestrogen daidzein, on body weight gain, intra-abdominal fat accumulation, plasma leptin, lipids, and glucose tolerance in ovariectomized rats and to compare them to the effects of 17beta-estradiol. DESIGN Twenty-eight female Sprague-Dawley rats were ovariectomized and fed soy-free chow with the addition of estradiol-3 benzoate (E2B) (10 mg/kg, n=10) or equol (400 mg/kg, n=10). The control group (n=8) received soy-free chow only. Weight and food intake were recorded once weekly. After 6 weeks, intra-abdominal fat was measured using computed tomography, and the intraperitoneal glucose tolerance test was performed. In the seventh week, the animals were killed, blood was collected for plasma, and uteri were removed. RESULTS Dietary equol significantly increased uterine mass. This effect was, however, 3.5 times lower in magnitude compared to E2B. Similar to E2B, dietary equol decreased weight gain, intra-abdominal fat accumulation, and plasma leptin levels. Equol-treated animals had also lower plasma total cholesterol and triglyceride levels compared to controls. E2B treatment also decreased plasma total cholesterol as well as high-density lipoprotein and low-density lipoprotein cholesterol. In the glucose tolerance test, the area under the curve was significantly smaller in the E2B- and equol-treated animals compared to controls. Also, E2B-treated animals had lower fasting plasma insulin levels. CONCLUSIONS In ovariectomized rats, dietary equol administration attenuates weight gain and shows favorable metabolic effects. However, because of its mild uterotrophic activity, its use in the prevention of postmenopausal weight gain and related metabolic disorders in women with an intact uterus is questionable in terms of safety and warrants further studies.
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Affiliation(s)
- Dominik Rachoń
- Department of Clinical and Experimental Endocrinology, University of Göttingen, Göttingen, Germany.
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17
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Van Pelt RE, Gozansky WS, Hickner RC, Schwartz RS, Kohrt WM. Acute modulation of adipose tissue lipolysis by intravenous estrogens. Obesity (Silver Spring) 2006; 14:2163-72. [PMID: 17189542 PMCID: PMC2832608 DOI: 10.1038/oby.2006.253] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE The aim of this study was to determine whether intravenous (IV) conjugated estrogens (EST) acutely enhance the suppression of whole-body or regional subcutaneous adipose tissue (SAT) lipolysis by insulin in postmenopausal women. RESEARCH METHODS AND PROCEDURES We assessed whole-body lipolysis by [(2)H(5)]glycerol rate of appearance (Glyc(RA)) and abdominal and femoral SAT lipolysis (interstitial glycerol; Glyc(IS)) by subcutaneous microdialysis. Postmenopausal women (n = 12) were studied on two occasions, with IV EST or saline control (CON), under basal conditions and during a 3-stage (4, 8, and 40 mU/m(2)/min) hyperinsulinemic, euglycemic clamp. Ethanol outflow/inflow ratio and recovery of [(13)C]glycerol during microdialysis were used to assess blood flow changes and interstitial glycerol concentrations, respectively. RESULTS Compared with CON, EST did not affect systemic basal or insulin-mediated suppression of lipolysis (Glyc(RA)) or SAT nutritive blood flow. Basal Glyc(IS) in SAT was reduced on the EST day. However, insulin-mediated suppression of lipolysis in SAT was not significantly influenced by EST. DISCUSSION These findings suggest that estrogens acutely reduce basal lipolysis in SAT through an unknown mechanism but do not alter whole-body or SAT suppression of lipolysis by insulin.
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Affiliation(s)
- Rachael E Van Pelt
- Department of Medicine, Division of Geriatric Medicine, University of Colorado at Denver and Health Sciences Center, 4200 E. Ninth Ave., Campus Box B-179, Denver, CO 80262, USA.
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18
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Abstract
The endocrine functions of the adipose organ are widely studied at this stage. The adipose organ, and in particular adipocytes, communicate with almost all other organs. Although some adipose tissue pads assume the functions as distinct "miniorgans," adipocytes can also be present in smaller numbers interspersed with other cell types. Although fat pads have the potential to have a significant systemic impact, adipocytes may also affect neighboring tissues through paracrine interactions. These local or systemic effects are mediated through lipid and protein factors. The protein factors are commonly referred to as adipokines. Their expression and posttranslational modifications can undergo dramatic changes under different metabolic conditions. Due to the fact that none of the mutations that affect adipose tissue trigger embryonic lethality, the study of adipose tissue physiology lends itself to genetic analysis in mice. In fact, life in the complete absence of adipose tissue is possible in a laboratory setting, making even the most extreme adipose tissue phenotypes genetically amenable to be analyzed by disruption of specific genes or overexpression of others. Here, we briefly discuss some basic aspects of adipocyte physiology and the systemic impact of adipocyte-derived factors on energy homeostasis.
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Affiliation(s)
- Maria E Trujillo
- Departments of Cell Biology and Medicine, Diabetes Research and Training Center, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, USA
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19
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Rodríguez-Cuenca S, Gianotti M, Roca P, Proenza AM. Sex steroid receptor expression in different adipose depots is modified during midpregnancy. Mol Cell Endocrinol 2006; 249:58-63. [PMID: 16504376 DOI: 10.1016/j.mce.2006.01.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 01/18/2006] [Accepted: 01/20/2006] [Indexed: 10/25/2022]
Abstract
Sex hormone signalling is key in the understanding of adipose tissue metabolism during pregnancy. Sex hormones play an important role in adipose tissue metabolism by activating specific receptors that alter several steps of lipolysis and lipogenesis. We analyze steroid receptor mRNA levels in different rat adipose depots and mammary fat pad, as well as the sex hormone profile during midpregnancy, coinciding with the placentation process. Thus, progesterone and estradiol plasma levels were increased as well as testosterone levels. This hormonal profile was accompanied by low glucose to insulin ratio. PR-B, ERalpha and AR receptor densities during midpregnancy were dependent on adipose depot location. In mammary fat pad, the mRNA levels of sex hormone receptors were correlated with the growth of the depot. These results demonstrate that sex steroid hormone receptor mRNA expression during midpregnancy is tissue-specific. Our results agree with the idea that the increased estrogenic and androgenic signalling could be addressed to reducing the lipogenic state in early pregnancy exerted mainly by progesterone and to prepare adipose tissue for the beginning of the catabolic phase in late pregnancy in a depot-specific manner.
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Affiliation(s)
- S Rodríguez-Cuenca
- Grup de Metabolisme Energètic i Nutrició, Departament de Biologia Fonamental i Ciències de la Salut, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Spain
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20
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D'Eon TM, Souza SC, Aronovitz M, Obin MS, Fried SK, Greenberg AS. Estrogen regulation of adiposity and fuel partitioning. Evidence of genomic and non-genomic regulation of lipogenic and oxidative pathways. J Biol Chem 2005; 280:35983-91. [PMID: 16109719 DOI: 10.1074/jbc.m507339200] [Citation(s) in RCA: 376] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Menopause is associated with increased adiposity and greater risk of metabolic disease. In the ovariectomized (OVX) rodent model of menopause, increased adiposity is prevented by estrogen (E2) replacement, reflecting both anorexigenic and potentially metabolic actions of E2. To elucidate metabolic and molecular mechanisms by which E2 regulates fat storage and fat mobilization independently of reduced energy intake, C57 BL/6 mice were ovariectomized, randomized to estrogen (OVX-E2) or control pellet implants (OVX-C), and pairfed for 40 days. E2 treatment was associated with reduced adipose mass and adipocyte size and down-regulation of lipogenic genes in adipocytes under the control of sterol-regulatory element-binding protein 1c. Adipocytes of OVX-E2 mice contained >3-fold more perilipin protein than adipocytes of pairfed control (OVX) mice, and this difference was associated with enhanced ex vivo lipolytic response to catecholamines and with greater levels of serum-free fatty acids following fasting. As in adipose tissue, E2 decreased the expression of lipogenic genes in liver and skeletal muscle. In the latter, E2 appears to promote the partitioning of free fatty acids toward oxidation and away from triglyceride storage by up-regulating the expression of peroxisome proliferation activator receptor-delta and its downstream targets and also by directly and rapidly activating AMP-activated protein kinase. Thus, novel genomic and non-genomic actions of E2 promote leanness in OVX mice independently of reduced energy intake.
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Affiliation(s)
- Tara M D'Eon
- Jean Mayer-United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts 02111, USA
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21
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Pedersen SB, Kristensen K, Hermann PA, Katzenellenbogen JA, Richelsen B. Estrogen controls lipolysis by up-regulating alpha2A-adrenergic receptors directly in human adipose tissue through the estrogen receptor alpha. Implications for the female fat distribution. J Clin Endocrinol Metab 2004; 89:1869-78. [PMID: 15070958 DOI: 10.1210/jc.2003-031327] [Citation(s) in RCA: 183] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Estrogen seems to promote and maintain the typical female type of fat distribution that is characterized by accumulation of adipose tissue, especially in the sc fat depot, with only modest accumulation of adipose tissue intraabdominally. However, it is completely unknown how estrogen controls the fat accumulation. We studied the effects of estradiol in vivo and in vitro on human adipose tissue metabolism and found that estradiol directly increases the number of antilipolytic alpha2A-adrenergic receptors in sc adipocytes. The increased number of alpha2A-adrenergic receptors caused an attenuated lipolytic response of epinephrine in sc adipocytes; in contrast, no effect of estrogen on alpha2A-adrenergic receptor mRNA expression was observed in adipocytes from the intraabdominal fat depot. These findings show that estrogen lowers the lipolytic response in sc fat depot by increasing the number of antilipolytic alpha2A-adrenergic receptors, whereas estrogen seems not to affect lipolysis in adipocytes from the intraabdominal fat depot. Using estrogen receptor subtype-specific ligands, we found that this effect of estrogen was caused through the estrogen receptor subtype alpha. These findings demonstrate that estrogen attenuates the lipolytic response through up-regulation of the number of antilipolytic alpha2A-adrenergic receptors only in sc and not in visceral fat depots. Thus, our findings offer an explanation how estrogen maintains the typical female sc fat distribution because estrogen seems to inhibit lipolysis only in sc depots and thereby shifts the assimilation of fat from intraabdominal depots to sc depots.
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Affiliation(s)
- Steen B Pedersen
- Department of Endocrinology and Metabolism, Aarhus Amtssygehus, Aarhus University Hospital, Denmark.
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22
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Jones ME, Thorburn AW, Britt KL, Hewitt KN, Misso ML, Wreford NG, Proietto J, Oz OK, Leury BJ, Robertson KM, Yao S, Simpson ER. Aromatase-deficient (ArKO) mice accumulate excess adipose tissue. J Steroid Biochem Mol Biol 2001; 79:3-9. [PMID: 11850201 DOI: 10.1016/s0960-0760(01)00136-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Aromatase is the enzyme which catalyses the conversion of C19 steroids into C18 estrogens. We have generated a mouse model wherein the Cyp19 gene, which encodes aromatase, has been disrupted, and hence, the aromatase knockout (ArKO) mouse cannot synthesise endogenous estrogens. We examined the consequences of estrogen deficiency on accumulation of adipose depots in male and female ArKO mice, observing that these animals progressively accrue significantly more intra-abdominal adipose tissue than their wildtype (WT) litter mates, reflected in increased adipocyte volume and number. This increased adiposity was not due to hyperphagia or reduced resting energy expenditure, but was associated with reduced spontaneous physical activity levels, reduced glucose oxidation, and a decrease in lean body mass. Elevated circulating levels of leptin and cholesterol were present in 1-year-old ArKO mice compared to WT controls, as were elevated insulin levels, although blood glucose was unchanged. Associated with these changes, the livers of ArKO animals were characterised by a striking accumulation of lipid droplets. Our findings demonstrate an important role for estrogen in the maintenance of lipid homeostasis in both males and females.
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Affiliation(s)
- M E Jones
- Prince Henry's Institute of Medical Research, P.O. Box 5152, Vic. 3168, Clayton, Australia.
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23
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Jones ME, Thorburn AW, Britt KL, Hewitt KN, Wreford NG, Proietto J, Oz OK, Leury BJ, Robertson KM, Yao S, Simpson ER. Aromatase-deficient (ArKO) mice have a phenotype of increased adiposity. Proc Natl Acad Sci U S A 2000; 97:12735-40. [PMID: 11070087 PMCID: PMC18833 DOI: 10.1073/pnas.97.23.12735] [Citation(s) in RCA: 544] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The aromatase-knockout (ArKO) mouse provides a useful model to examine the role that estrogens play in development and homeostasis in mammals. Lacking a functional Cyp19 gene, which encodes aromatase, the ArKO mouse cannot synthesize endogenous estrogens. We examined the adipose depots of male and female ArKO mice, observing that these animals progressively accumulate significantly more intraabdominal adipose tissue than their wild-type (WT) littermates, reflected in increased adipocyte volume at gonadal and infrarenal sites. This increased adiposity was not due to hyperphagia or reduced resting energy expenditure, but was associated with reduced spontaneous physical activity levels, reduced glucose oxidation, and a decrease in lean body mass. Elevated circulating levels of leptin and cholesterol were present in 1-year-old ArKO mice compared with WT controls, as were elevated insulin levels, although blood glucose levels were unchanged. Associated with these changes, a striking accumulation of lipid droplets was observed in the livers of ArKO animals. Our findings demonstrate an important role for estrogen in the maintenance of lipid homeostasis in both males and females.
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Affiliation(s)
- M E Jones
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia.
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24
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Garcia E, Lacasa D, Giudicelli Y. Estradiol stimulation of c-fos and c-jun expressions and activator protein-1 deoxyribonucleic acid binding activity in rat white adipocyte. Endocrinology 2000; 141:2837-46. [PMID: 10919270 DOI: 10.1210/endo.141.8.7610] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In order to elucidate the molecular mechanisms whereby ovarian hormones, and particularly estrogens, modulate fat cell metabolism, we investigated the effects of estradiol administration on c-fos and c-jun expressions in fat cells from ovariectomized (OVX) rats. Estradiol treatment resulted in a rapid increase in c-fos and c-jun messenger RNA (mRNA) and protein levels (about 2-fold). These effects of estradiol on c-fos and c-jun mRNAs were blocked by actinomycin D but not by cycloheximide treatment, suggesting that estradiol modulates c-fos and c-jun transcription. Moreover, the estradiol-induction of both transcripts was partially suppressed by the estrogen-receptor antagonist ICI 182,780. In contrast, progesterone administration did not affect c-fos and c-jun mRNA levels indicating a hormonal specificity of estrogen action. However, an antagonism of estradiol-induction of both genes was observed after progesterone treatment. In addition, the estradiol-induced changes in c-fos and c-jun mRNA expressions could not be observed in castrated males suggesting a gender-specific effect of estradiol. Finally, in OVX rats, estradiol treatment stimulated the specific AP-1 DNA binding activity (about 5-fold) in adipocyte nuclear extracts as assessed by electrophoretic mobility shift assays. These results suggest that some of the estrogen effects in fat cells from female rats are mediated through induction of the AP-1 complex expression and consequently through modulation of the AP-1 dependent gene expression in adipocytes.
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Affiliation(s)
- E Garcia
- Department of Biochemistry and Molecular Biology, Faculty of Medicine Paris-Ouest, Université Paris V and Centre Hospitalier, Poissy, France
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25
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Hansen DK, Davies MI, Lunte SM, Lunte CE. Pharmacokinetic and metabolism studies using microdialysis sampling. J Pharm Sci 1999; 88:14-27. [PMID: 9874697 PMCID: PMC2519818 DOI: 10.1021/js9801485] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- D K Hansen
- Departments of Chemistry and Pharmaceutical Chemistry and the Center for Bioanalytical Research, University of Kansas, Lawrence, Kansas 66047, USA
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