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Abe T, Song JS, Bell ZW, Wong V, Spitz RW, Yamada Y, Loenneke JP. Comparisons of calorie restriction and structured exercise on reductions in visceral and abdominal subcutaneous adipose tissue: a systematic review. Eur J Clin Nutr 2022; 76:184-195. [PMID: 34040197 DOI: 10.1038/s41430-021-00942-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 05/02/2021] [Accepted: 05/12/2021] [Indexed: 01/06/2023]
Abstract
Exercise and low-calorie diets are common approaches taken to produce an energy deficit for weight loss in obesity. Changes in visceral and abdominal subcutaneous fat associated with weight loss are important questions but have not yet been concluded. We investigated the relationship between changes in visceral (VAT) and subcutaneous adipose tissue (SAT) areas obtained by abdominal imaging with the change in total body fat. The relevant databases were searched through January 2021 according to the PRISMA guidelines. Sixty-five studies were included. We found that the change in total body fat was associated with changes in both VAT and abdominal SAT areas, but the relationship between total body fat and the abdominal SAT area appeared stronger. Baseline values of VAT and abdominal SAT area were similar in the three treatment groups (calorie restriction, calorie restriction plus exercise, and exercise alone). The reduction in abdominal SAT area for a loss of 1 kg of total body fat was about 10 cm2, which was similar among all the treatments. The change in VAT area (-26.3 cm2) was a similar level as the change in abdominal SAT area (-31.5 cm2) in the exercise, whereas in the calorie restriction with and without exercise, the change in VAT area (-33.6 and -51.6 cm2, respectively) was approximately half of the reduction of SAT area (-65.1 and -87.2 cm2, respectively). Absolute changes in VAT and abdominal SAT areas might differ between interventions for the exercise and calorie restriction with and without exercise.
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Affiliation(s)
- Takashi Abe
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA. .,Graduate School of Health and Sports Science, Juntendo University, Inzai, Chiba, Japan.
| | - Jun Seob Song
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
| | - Zachary W Bell
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
| | - Vickie Wong
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
| | - Robert W Spitz
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
| | - Yujiro Yamada
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
| | - Jeremy P Loenneke
- Department of Health, Exercise Science, and Recreation Management, Kevser Ermin Applied Physiology Laboratory, The University of Mississippi, Oxford, MS, USA
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Effect of Breast Cancer and Adjuvant Therapy on Adipose-Derived Stromal Cells: Implications for the Role of ADSCs in Regenerative Strategies for Breast Reconstruction. Stem Cell Rev Rep 2020; 17:523-538. [PMID: 32929604 DOI: 10.1007/s12015-020-10038-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2020] [Indexed: 12/14/2022]
Abstract
Tissue engineering using Adipose Derived Stromal Cells (ADSCs) has emerged as a novel regenerative medicine approach to replace and reconstruct soft tissue damaged or lost as a result of disease process or therapeutic surgical resection. ADSCs are an attractive cell source for soft tissue regeneration due to the fact that they are easily accessible, multipotent, non-immunogenic and pro-angiogenic. ADSC based regenerative strategies have been successfully translated to the clinical setting for the treatment of Crohn's fistulae, musculoskeletal pathologies, wound healing, and cosmetic breast augmentation (fat grafting). ADSCs are particularly attractive as a source for adipose tissue engineering as they exhibit preferential differentiation to adipocytes and support maintenance of mature adipose graft volume. The potential for reconstruction with an autologous tissue sources and a natural appearance and texture is particularly appealing in the setting of breast cancer; up to 40% of patients require mastectomy for locoregional control and current approaches to post-mastectomy breast reconstruction (PMBR) are limited by the potential for complications at the donor and reconstruction sites. Despite their potential, the use of ADSCs in breast cancer patients is controversial due to concerns regarding oncological safety. These concerns relate to the regeneration of tissue at a site where a malignancy has been treated and the impact this may have on stimulating local disease recurrence or dissemination. Pre-clinical data suggest that ADSCs exhibit pro-oncogenic characteristics and are involved in stimulating progression, and growth of tumour cells. However, there have been conflicting reports on the oncologic outcome, in terms of locoregional recurrence, for breast cancer patients in whom ADSC enhanced fat grafting was utilised as an alternative to reconstruction for small volume defects. A further consideration which may impact the successful translation of ADSC based regenerative strategies for post cancer reconstruction is the potential effects of cancer therapy. This review aims to address the effect of malignant cells, adjuvant therapies and patient-specific factors that may influence the success of regenerative strategies using ADSCs for post cancer tissue regeneration.
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Boa BCS, Yudkin JS, van Hinsbergh VWM, Bouskela E, Eringa EC. Exercise effects on perivascular adipose tissue: endocrine and paracrine determinants of vascular function. Br J Pharmacol 2017; 174:3466-3481. [PMID: 28147449 DOI: 10.1111/bph.13732] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 01/20/2017] [Accepted: 01/23/2017] [Indexed: 12/11/2022] Open
Abstract
Obesity is a global epidemic, accompanied by increased risk of type 2 diabetes and cardiovascular disease. Adipose tissue hypertrophy is associated with adipose tissue inflammation, which alters the secretion of adipose tissue-derived bioactive products, known as adipokines. Adipokines determine vessel wall properties such as smooth muscle tone and vessel wall inflammation. Exercise is a mainstay of prevention of chronic, non-communicable diseases, type 2 diabetes and cardiovascular disease in particular. Aside from reducing adipose tissue mass, exercise has been shown to reduce inflammatory activity in this tissue. Mechanistically, contracting muscles release bioactive molecules known as myokines, which alter the metabolic phenotype of adipose tissue. In adipose tissue, myokines induce browning, enhance fatty acid oxidation and improve insulin sensitivity. In the past years, the perivascular adipose tissue (PVAT) which surrounds the vasculature, has been shown to control vascular tone and inflammation through local release of adipokines. In obesity, an increase in mass and inflammation of PVAT culminate in dysregulation of adipokine secretion, which contributes to vascular dysfunction. This review describes our current understanding of the mechanisms by which active muscles interact with adipose tissue and improve vascular function. Aside from the exercise-dependent regulation of canonical adipose tissue function, we will focus on the interactions between skeletal muscle and PVAT and the role of novel myokines, such as IL-15, FGF21 and irisin, in these interactions. LINKED ARTICLES This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.
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Affiliation(s)
- B C S Boa
- Department of Physiology, VU University Medical Centre, Amsterdam, The Netherlands.,Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - J S Yudkin
- Department of Medicine, University College London, London, UK
| | - V W M van Hinsbergh
- Department of Physiology, VU University Medical Centre, Amsterdam, The Netherlands
| | - E Bouskela
- Laboratory for Clinical and Experimental Research on Vascular Biology (BioVasc), Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - E C Eringa
- Department of Physiology, VU University Medical Centre, Amsterdam, The Netherlands
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Bando S, Fukuda D, Soeki T, Nishimoto S, Uematsu E, Matsuura T, Ise T, Tobiume T, Yamaguchi K, Yagi S, Iwase T, Yamada H, Wakatsuki T, Shimabukuro M, Sata M. Expression of NLRP3 in subcutaneous adipose tissue is associated with coronary atherosclerosis. Atherosclerosis 2015; 242:407-14. [DOI: 10.1016/j.atherosclerosis.2015.07.043] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 07/23/2015] [Accepted: 07/27/2015] [Indexed: 12/16/2022]
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Inflammatory characteristics of distinct abdominal adipose tissue depots relate differently to metabolic risk factors for cardiovascular disease. Atherosclerosis 2015; 239:419-27. [DOI: 10.1016/j.atherosclerosis.2015.01.035] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 01/23/2015] [Accepted: 01/23/2015] [Indexed: 12/25/2022]
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Gao M, Wang M, Guo X, Qiu X, Liu L, Liao J, Liu J, Lu G, Wang Y, Liu G. Expression of seipin in adipose tissue rescues lipodystrophy, hepatic steatosis and insulin resistance in seipin null mice. Biochem Biophys Res Commun 2015; 460:143-50. [PMID: 25757906 DOI: 10.1016/j.bbrc.2015.02.147] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 02/25/2015] [Indexed: 01/17/2023]
Abstract
OBJECTIVES Gene mutations in an ER protein seipin result in congenital generalized lipodystrophy (CGL) in humans, accompanied with hepatic steatosis and insulin resistance. Seipin gene is highly expressed in the brain, testis and adipose tissue. Seipin globally deficient mice (SKO) displayed similar phenotypes as human counterparts. It has been demonstrated that adipose-specific seipin knockout mice at elder age were indistinguishable from SKO mice. Due to the large mass of adipose tissue in the body, we hypothesized that seipin in adipose tissue might be responsible for the multiple metabolism-related abnormalities in SKO mice. METHODS AND RESULTS Transgenic mice with adipose-specific expression of human seipin gene driven by aP2 promoter were generated and crossed with SKO mice to obtain adipose-specific seipin reconstitute (Seipin-RE) mice. In comparison with wild-type (WT) and SKO mice, the Seipin-RE mice exhibited normal plasma triglyceride and non-esterified fatty acids upon fasting, recovered adipose tissue mass, restored epididymal and subcutaneous fat pads morphology and partially recovered plasma leptin and adiponectin levels. Moreover, hepatic steatosis and insulin resistance was also absent in these mice. CONCLUSION Our study demonstrates that expression of seipin in adipose tissue alone could rescue dyslipidemia, lipodystrophy, hepatic steatosis and insulin resistance in SKO mice.
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Affiliation(s)
- Mingming Gao
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Mengyu Wang
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Xin Guo
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Xu Qiu
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Lu Liu
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Jiawei Liao
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Jinjiao Liu
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - Guotao Lu
- Department of General Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu Province, 210093, China
| | - Yuhui Wang
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China
| | - George Liu
- Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University Health Science Center, Beijing, 100191, China.
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Adipose tissue fatty acid storage factors: effects of depot, sex and fat cell size. Int J Obes (Lond) 2015; 39:884-7. [PMID: 25640767 PMCID: PMC4464947 DOI: 10.1038/ijo.2015.10] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 01/02/2015] [Accepted: 01/18/2015] [Indexed: 02/01/2023]
Abstract
Background/Objectives Patterns of postabsorptive adipose tissue fatty acid storage correlate with sex-specific body fat distribution. Some proteins and enzymes participating in this pathway include CD36 (facilitated transport), acyl-CoA synthetases (ACS; the first step in fat metabolism), and diacylglycerol acetyl-transferase (DGAT; the final step of triglyceride synthesis). Our goal was to better define CD36, ACS and DGAT in relation to sex, subcutaneous fat depots, and adipocyte size. Subjects/Methods Data was collected from studies conducted at Mayo Clinic between 2004 and 2012. Abdominal and femoral subcutaneous fat biopsy samples must have been collected in the postabsorptive state from healthy males and premenopausal females. Body composition was measured with DXA and abdominal CT scans. Adipocyte size (microscopy), CD36 protein content (ELISA), and ACS and DGAT enzyme activities were measured. Data are presented as medians; 25th:75th quartiles. Results Males (n=60) and females (n=78) did not differ by age (37;28:46 yr), BMI (28.4;24.6:32.1 kg/m2), or abdominal (0.60;0.45:0.83 μg/cell) and femoral adipocyte size (0.76;0.60:0.94 μg/cell). Femoral ACS and DGAT were greater in females than males when expressed per mg lipid (ACS: 73 vs. 55 pmol/mg lipid/min; DGAT: 5.5 vs. 4.0 pmol/ mg lipid/min; p<0.0001 for both) and per 1000 adipocytes (ACS: 59 vs. 39 pmol/1000adipocytes/min; DGAT: 4.3 vs. 3.1 pmol/1000adipocytes/min; p≤0.0003 for both). There were no differences in abdominal fat storage factors between sexes. ACS and DGAT decreased as a function of adipocyte size (p<0.0001 for both). The decrease in ACS was greater in males and abdominal subcutaneous fat. There were no sex differences in CD36 in either fat depot, nor did it vary across adipocyte size. Conclusions Facilitated transport of fatty acids by CD36 under postabsorptive conditions would not be different in those with large vs. small adipocytes in either depot of both sexes. However, intracellular trafficking of fatty acids to triglyceride storage by ACS and DGAT may be less efficient in larger adipocytes.
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Friedauer K, Dänicke S, Schulz K, Sauerwein H, Häussler S. Detection of 11 beta-hydroxysteroid dehydrogenase type 1, the glucocorticoid and mineralocorticoid receptor in various adipose tissue depots of dairy cows supplemented with conjugated linoleic acids. J Anim Physiol Anim Nutr (Berl) 2014; 99:950-61. [PMID: 25354306 DOI: 10.1111/jpn.12268] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 09/19/2014] [Indexed: 12/14/2022]
Abstract
Early lactating cows mobilize adipose tissue (AT) to provide energy for milk yield and maintenance and are susceptible to metabolic disorders and impaired immune response. Conjugated linoleic acids (CLA), mainly the trans-10, cis-12 isomer, reduce milk fat synthesis and may attenuate negative energy balance. Circulating glucocorticoids (GC) are increased during parturition in dairy cows and mediate differentiating and anti-inflammatory effects via glucocorticoid (GR) and mineralocorticoid receptors (MR) in the presence of the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1). Activated GC are the main ligands for both receptors in AT; therefore, we hypothesized that tissue-specific GC metabolism is effected by varying amounts of GR, MR and 11βHSD1 and/or their localization within AT depots. Furthermore, the lipolytic and antilipogenic effects of CLA might influence the GC/GR/MR system in AT. Therefore, we aimed to localize GR and MR as well as the expression pattern and activity of 11βHSD1 in different AT depots during early lactation in dairy cows and to identify potential effects of CLA. Primiparous German Holstein cows were divided into a control (CON) and a CLA group. From day 1 post-partum (p.p.) until sample collection, the CLA group was fed with 100 g/d CLA (contains 10 g each of the cis-9, trans-11 and the trans-10, cis-12-CLA isomers). CON cows (n = 5 each) were slaughtered on day 1, 42 and 105 p.p., while CLA cows (n = 5 each) were slaughtered on day 42 and 105 p.p. Subcutaneous fat from tailhead, withers and sternum, and visceral fat from omental, mesenteric and retroperitoneal depots were sampled. The localization of GR and 11βHSD1 in mature adipocytes - being already differentiated - indicates that GC promote other effects via GR than differentiation. Moreover, MR were observed in the stromal vascular cell fraction and positively related to the pre-adipocyte marker Pref-1. However, only marginal CLA effects were observed in this study.
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Affiliation(s)
- K Friedauer
- Physiology and Hygiene Group, Institute of Animal Science, University of Bonn, Bonn, Germany
| | - S Dänicke
- Institute of Animal Nutrition, Friedrich-Loeffler-Institute (FLI), Federal Research Institute for Animal Health, Braunschweig, Germany
| | - K Schulz
- Physiology and Hygiene Group, Institute of Animal Science, University of Bonn, Bonn, Germany
| | - H Sauerwein
- Physiology and Hygiene Group, Institute of Animal Science, University of Bonn, Bonn, Germany
| | - S Häussler
- Physiology and Hygiene Group, Institute of Animal Science, University of Bonn, Bonn, Germany
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Speaker KJ, Cox SS, Paton MM, Serebrakian A, Maslanik T, Greenwood BN, Fleshner M. Six weeks of voluntary wheel running modulates inflammatory protein (MCP-1, IL-6, and IL-10) and DAMP (Hsp72) responses to acute stress in white adipose tissue of lean rats. Brain Behav Immun 2014; 39:87-98. [PMID: 24246250 PMCID: PMC4301739 DOI: 10.1016/j.bbi.2013.10.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 10/01/2013] [Accepted: 10/25/2013] [Indexed: 12/12/2022] Open
Abstract
To prime local tissues for dealing with potential infection or injury, exposure to an acute, intense stressor evokes increases in circulating and local tissue inflammatory proteins. Regular physical activity facilitates stress-evoked innate reactivity and modulates the expression of inflammatory proteins in immuno-metabolic tissues such as white adipose tissue (WAT). The impact of regular physical activity on stress-evoked inflammatory protein expression in WAT, however, remains unclear. To investigate this question, lean male F344 rats (150-175g) were allowed voluntary access to a running wheel for 6weeks followed by exposure to an acute stressor (100, 1.5mA-5s inescapable tail shocks). Using ELISAs, corticosterone, heat shock protein 72 (Hsp72), macrophage chemoattractant protein (MCP-1), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, and IL-10 concentrations were measured in plasma and subcutaneous, intraperitoneal (epididymal and retroperitoneal WAT depots) and visceral (omental and mesenteric WAT depots) WAT compartments. Acute stress increased plasma concentrations of all proteins except TNF-α and, depending upon the compartment examined, WAT concentrations of MCP-1, IL-1β, IL-6, and IL-10. Exercise ubiquitously increased IL-1β within WAT, potentiated stress-evoked Hsp72 in plasma and WAT, and differentially increased stress-evoked MCP-1, IL-6, and IL-10 within WAT. These data suggest: (a) inflammatory proteins in non-obese WAT may serve compartment-specific immune and metabolic roles important to the acute stress response and; (b) voluntary habitual exercise may optimize stress-induced augmentation of innate immune function through increases in stress-evoked Hsp72, MCP-1, IL-6, and IL-10 and decreases in IL-1β/IL10 and TNF-α/IL10 ratios within white adipose tissue.
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Affiliation(s)
- Kristin J. Speaker
- Department of Integrative Physiology, University of Colorado at Boulder, USA
| | - Stewart S. Cox
- Department of Integrative Physiology, University of Colorado at Boulder, USA
| | - Madeline M. Paton
- Department of Integrative Physiology, University of Colorado at Boulder, USA
| | - Arman Serebrakian
- Department of Integrative Physiology, University of Colorado at Boulder, USA
| | - Thomas Maslanik
- Department of Integrative Physiology, University of Colorado at Boulder, USA
| | - Benjamin N. Greenwood
- Department of Integrative Physiology, University of Colorado at Boulder, USA, Center for Neuroscience, University of Colorado at Boulder, USA
| | - Monika Fleshner
- Department of Integrative Physiology, University of Colorado at Boulder, USA; Center for Neuroscience, University of Colorado at Boulder, USA.
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Bays H, Blonde L, Rosenson R. Adiposopathy: how do diet, exercise and weight loss drug therapies improve metabolic disease in overweight patients? Expert Rev Cardiovasc Ther 2014; 4:871-95. [PMID: 17173503 DOI: 10.1586/14779072.4.6.871] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An increase in bodyweight is generally associated with an increased risk of excessive fat-related metabolic diseases (EFRMD), including Type 2 diabetes mellitus, hypertension and dyslipidemia. However, not all patients who are overweight have EFRMD, and not all patients with EFRMD are significantly overweight. The adipocentric paradigm provides the basis for a unifying, pathophysiological process whereby fat gain in susceptible patients leads to fat dysfunction ('sick fat'), and wherein pathological abnormalities in fat function (adiposopathy) are more directly related to the onset of EFRMD than increases in fat mass (adiposity) alone. But just as worsening fat function worsens EFRMD, improved fat function improves EFRMD. Peroxisome proliferator-activated receptor-gamma agonists increase the recruitment, proliferation and differentiation of preadipocytes ('healthy fat') and cause apoptosis of hypertrophic and dysfunctional (including visceral) adipocytes resulting in improved fat function and improved metabolic parameters associated with EFRMD. Weight loss interventions, such as a hypocaloric diet and physical exercise, in addition to agents such as orlistat, sibutramine and cannabinoid receptor antagonists, may have favorable effects upon fat storage (lipogenesis and fat distribution), nutrient metabolism (such as free fatty acids), favorable effects upon adipose tissue factors involved in metabolic processes and inflammation, and enhanced 'cross-talk' with other major organ systems. In some cases, weight loss therapeutic agents may even affect metabolic parameters and adipocyte function independently of weight loss alone, suggesting that the benefit of these agents in improving EFRMD may go beyond their efficacy in weight reduction. This review describes how adiposopathy interventions may affect fat function, and thus improve EFRMD.
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Affiliation(s)
- Harold Bays
- L-MARC Research Center, Medical Director/President, 3288 Illinois Avenue, Louisville, KY 40213, USA.
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Abstract
BACKGROUND AND AIMS The initial disturbance of insulin resistance seems to focus on adipose tissue is a dynamic organ involved in many physiological and metabolic processes. Expresses and secretes a variety of active peptides, adipocytokines. To evaluate the prevalence of insulin-resistance in an healthy urban middle age population and to explore the role of adiponectin, inflammatory biomarkers (hs-CRP) and traditional cardiovascular risk factors as predictors of the insulin-resistance state. MATERIALS AND METHODS We studied of 176 participants (117 women and 59 men, 25-74 years), individuals with diabetes, hypothyroidism or hyperthyroidism, infectious disease, renal, or hepatic neoplasms and pregnant women were excluded. We evaluated glucose, insulin, adiponectin and hs-CRP. RESULTS We found that 17.2% of individuals presented insulin-resistance. Correlation was found between waist circumference, body mass index, blood pressure and HOMA index (p<0.01). Adiponectin was associated with the insulin-resistance (p<0.001) but not hs-CRP. Adiponectin (β=0.385, p=0.004) and waist circumference (β=0.116, p=0.02) were predictors of IR only in women, meanwhile none of the analyzed biomarkers predicted insulin-resistance in men. Besides, postmenopausal women presented higher adiponectin levels than premenopausal 7.63 (4.46-9.58) vs 5.50 (3.83-7.40) μg/ml, p=0.01. CONCLUSIONS Adiponectin and waist circumference are important predictors of insulin-resistance even in healthy non-diabetic women, they may open a new opportunity to improve current risk estimation.
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Affiliation(s)
- Graciela A Bonneau
- Ministerio de Salud Pública de la Provincia de Misiones, Argentina; Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones, Argentina.
| | | | - Gabriela Berg
- Lipids and Lipoproteins Laboratory, Faculty of Pharmacy and Biochemistry, INFIBIOC, University of Buenos Aires, Argentina
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Rothney MP, Catapano AL, Xia J, Wacker WK, Tidone C, Grigore L, Xia Y, Ergun DL. Abdominal visceral fat measurement using dual-energy X-ray: association with cardiometabolic risk factors. Obesity (Silver Spring) 2013; 21:1798-802. [PMID: 23696250 DOI: 10.1002/oby.20223] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 11/19/2012] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To examine the association between cardiometabolic risk factors and visceral adipose tissue (VAT) measurements using a dual-energy X-ray absorptiometry (DXA) based approach. DESIGN AND METHODS An analysis of cross-sectional relationships between DXA VAT measured using CoreScan (GE Healthcare) and cardiometabolic indicators was conducted on a sample of 939 subjects (541 females and 398 males; average age, 56 years; average BMI, 26 kg/m2) who had previously undergone a total body DXA scan as well as measurements of key cardiometabolic risk factors. RESULTS Sex-specific, age-adjusted multivariable regression analysis showed that for both men and women, DXA VAT was significantly associated with increased odds of hypertension, impaired fasting glucose, metabolic syndrome, and type 2 diabetes (P < 0.001). After additional model adjustment for BMI and waist circumference, the odds ratio (per SD change in VAT) for type 2 diabetes was 2.07 for women and 2.25 for men. Similarly, the odds ratio for metabolic syndrome for women was 3.46 and for men was 1.75. CONCLUSIONS VAT measured using DXA showed a significant association with cardiometabolic risk factors and disease. These relationships persist after statistical adjustment for age, BMI, and waist circumference. DXA VAT may provide a new accessible option for quantifying VAT-related cardiometabolic risk.
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Affiliation(s)
- Megan P Rothney
- Computational Biology and Biostatistics Laboratory, GE Global Research Center, Niskayuna, New York, USA
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Speaker KJ, Fleshner M. Interleukin-1 beta: a potential link between stress and the development of visceral obesity. BMC PHYSIOLOGY 2012; 12:8. [PMID: 22738239 PMCID: PMC3404929 DOI: 10.1186/1472-6793-12-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 06/27/2012] [Indexed: 12/22/2022]
Abstract
Background A disproportionate amount of body fat within the abdominal cavity, otherwise known as visceral obesity, best predicts the negative health outcomes associated with high levels body fat. Growing evidence suggests that repeated activation of the stress response can favor visceral fat deposition and that visceral obesity may induce low-grade, systemic inflammation which is etiologically linked to the pathogenesis of obesity related diseases such as cardiovascular disease and type 2 diabetes. While the obesity epidemic has fueled considerable interest in these obesity-related inflammatory diseases, surprisingly little research is currently focused on understanding the functions of inflammatory proteins in healthy, non-obese white adipose tissue (WAT) and their possible role in modulating stress-induced shifts in body fat distribution. Hypothesis The current review presents evidence in support the novel hypothesis that stress-evoked interleukin-1 beta (IL-1β) signaling within subcutaneous adipose tissue, when repeatedly induced, contributes toward the development of visceral obesity. It is suggested that because acute stressor exposure differentially increases IL-1β levels within subcutaneous adipose relative to visceral adipose tissue in otherwise healthy, non-obese rats, repeated induction of this response may impair the ability of subcutaneous adipose tissue to uptake energy substrates, synthesize and retain triglycerides, and/or adapt to positive energy balance via hyperplasia. Consequently, circulating energy substrates may be disproportionately shunted to visceral adipose tissue for storage, thus driving the development of visceral obesity. Conclusions This review establishes the following key points: 1) body fat distribution outweighs the importance of total body fat when predicting obesity-related disease risk; 2) repeated exposure to stress can drive the development of visceral obesity independent of changes in body weight; 3) because of the heterogeneity of WAT composition and function, an accurate understanding of WAT responses requires sampling multiple WAT depots; 4) acute, non-pathogenic stressor exposure increases WAT IL-1β concentrations in a depot specific manner suggesting an adaptive, metabolic role for this cytokine; however, when repeated, stress-induced IL-1β in non-visceral WAT may result in functional impairments that drive the development of stress-induced visceral obesity.
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Affiliation(s)
- Kristin J Speaker
- Department of Integrative Physiology, University of Colorado at Boulder, 80309, USA
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Abstract
New and more effective nutritional measures are urgently needed for the prevention of obesity. The role of Ca and vitamin D in obesity has been recently implicated. Low Ca intake and low vitamin D status have been linked with an increased risk of obesity in epidemiological studies; however, clinical intervention trials designed to test this association have produced controversial results. The suggested anti-obesity mechanisms of Ca and vitamin D include the regulation of adipocyte death (apoptosis), adipogenesis and lipid metabolism. Dietary Ca has been also shown to increase faecal fat excretion. The potential role of Ca and vitamin D in shifting energy balance towards a more negative state is an area of considerable interest. Ultimately, a review of recent research findings does not allow the reaching of a definitive conclusion that increasing Ca intake and rising vitamin D status will influence fat mass and body weight or decrease the risk of obesity and overweight.
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Abdominal Obesity and Metabolic Alterations in the Menopausal Transition. CURRENT OBSTETRICS AND GYNECOLOGY REPORTS 2012. [DOI: 10.1007/s13669-012-0011-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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16
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Catta-Preta M, Martins MA, Cunha Brunini TM, Mendes-Ribeiro AC, Mandarim-de-Lacerda CA, Aguila MB. Modulation of cytokines, resistin, and distribution of adipose tissue in C57BL/6 mice by different high-fat diets. Nutrition 2012; 28:212-9. [DOI: 10.1016/j.nut.2011.05.011] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 04/16/2011] [Accepted: 05/10/2011] [Indexed: 01/24/2023]
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17
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Versey HS, Kaplan GA. Mediation and moderation of the association between cynical hostility and systolic blood pressure in low-income women. HEALTH EDUCATION & BEHAVIOR 2011; 39:219-28. [PMID: 22167318 DOI: 10.1177/1090198111414884] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hostility may be related to risk factors for cardiovascular disease (CVD), such as blood pressure. However, the process by which hostility affects blood pressure is not fully understood. The current study sought to evaluate abdominal obesity (waist-to-hip ratio [WHR]) as a potential mediator and modifier of the relationship between cynical hostility and systolic blood pressure (SBP) in a group of disadvantaged women. Path analysis and multiple regression models were used to identify mediating and moderating pathways in the relationship between cynical hostility and SBP. Results indicate a significant interaction between WHR and cynical hostility. WHR was a partial mediator and significant moderator of the association between hostility and blood pressure. These findings highlight the potential importance of examining abdominal obesity and psychosocial factors as conjunctive determinants of CVD and risk factors for related metabolic conditions.
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Affiliation(s)
- H Shellae Versey
- Department of Psychology, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA.
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18
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Lustgarten MS, Fielding RA. Assessment of analytical methods used to measure changes in body composition in the elderly and recommendations for their use in phase II clinical trials. J Nutr Health Aging 2011; 15:368-75. [PMID: 21528163 PMCID: PMC3376910 DOI: 10.1007/s12603-011-0049-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
It is estimated that in the next 20 years, the amount of people greater than 65 years of age will rise from 40 to 70 million, and will account for 19% of the total population. Age-related decreases in muscle mass and function, known as sarcopenia, have been shown to be related to functional limitation, frailty and an increased risk of morbidity and mortality. Therefore, with an increasing elderly population, interventions that can improve muscle mass content and/or function are essential. However, analytical techniques used for measurement of muscle mass in young subjects may not be valid for use in the elderly. Therefore, the purpose of this review is to examine the applied specificity and accuracy of methods that are commonly used for measurement of muscle mass in aged subjects, and, to propose specific recommendations for the use of body composition measures in phase II clinical trials of function-promoting anabolic therapies.
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Affiliation(s)
- M S Lustgarten
- Nutrition, Exercise Physiology and Sarcopenia Laboratory, Jean Mayer USDA Human Research Center on Aging, Tufts University, Boston, MA 02111-1524, USA
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19
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Deng Y, Scherer PE. Adipokines as novel biomarkers and regulators of the metabolic syndrome. Ann N Y Acad Sci 2011. [PMID: 21276002 DOI: 10.1111/j.1749-6632.2010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Over the past two decades our view of adipose tissue has undergone a dramatic change from an inert energy storage tissue to an active endocrine organ. Adipose tissue communicates with other central and peripheral organs by synthesis and secretion of a host of molecules that we generally refer to as adipokines. The levels of some adipokines correlate with specific metabolic states and have the potential to impact directly upon the metabolic homeostasis of the system. A dysregulation of adipokines has been implicated in obesity, type 2 diabetes, hypertension, cardiovascular disease, and an ever-growing larger list of pathological changes in a number of organs. Here, we review the recent progress regarding the synthesis, secretion, and physiological function of adipokines with perspectives on future directions and potential therapeutic goals.
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Affiliation(s)
- Yingfeng Deng
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, USA
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20
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Deng Y, Scherer PE. Adipokines as novel biomarkers and regulators of the metabolic syndrome. Ann N Y Acad Sci 2011; 1212:E1-E19. [PMID: 21276002 DOI: 10.1111/j.1749-6632.2010.05875.x] [Citation(s) in RCA: 360] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Over the past two decades our view of adipose tissue has undergone a dramatic change from an inert energy storage tissue to an active endocrine organ. Adipose tissue communicates with other central and peripheral organs by synthesis and secretion of a host of molecules that we generally refer to as adipokines. The levels of some adipokines correlate with specific metabolic states and have the potential to impact directly upon the metabolic homeostasis of the system. A dysregulation of adipokines has been implicated in obesity, type 2 diabetes, hypertension, cardiovascular disease, and an ever-growing larger list of pathological changes in a number of organs. Here, we review the recent progress regarding the synthesis, secretion, and physiological function of adipokines with perspectives on future directions and potential therapeutic goals.
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Affiliation(s)
- Yingfeng Deng
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, USA
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21
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Gorgey AS, Mather KJ, Poarch HJ, Gater DR. Influence of motor complete spinal cord injury on visceral and subcutaneous adipose tissue measured by multi-axial magnetic resonance imaging. J Spinal Cord Med 2011; 34:99-109. [PMID: 21528633 PMCID: PMC3066490 DOI: 10.1179/107902610x12911165975106] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
OBJECTIVE Abdominal obesity conveys substantial health risks, in association with high levels of visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and an increased proportion of VAT to SAT. The purposes were to determine the influence of spinal cord injury (SCI) on the associations between single axial cross-sectional area (CSA) slices and the average CSA or volumes of VAT and SAT across multi-axial slices of magnetic resonance imaging (MRI); and the relationships relative to the whole body composition and anthropometrics. METHODS Thirteen healthy male participants with traumatic motor complete SCI underwent fast spin-echo MRI to measure VAT and SAT across multi-axial slices, followed by dual-energy X-ray absorptiometry to measure whole body fat-free mass (FFM) and fat mass (FM). Waist circumference (WC) was also measured in the seated position. RESULTS The trunk CSAs of VAT and SAT were 99 +/- 51 and 164 +/- 69 cm2, respectively, and the ratio of VAT to SAT was 0.68 +/- 0.33. The CSAs of VAT and SAT at a single slice strongly predicted the average CSA and modestly predicted the volumes across multi-axial slices. VAT and SAT represented 5.7 +/- 1.8% and 9.7 +/- 3.2% of the total body FM, respectively. Percent body FFM was negatively related to VAT and SAT volumes, but not to a single axial CSA. CONCLUSION A single slice CSA can modestly predict the volume of multi-axial slices in individuals with SCI, yet it is not related to any of the body composition variables. Increased percent FFM is associated with a reduction in VAT and SAT volumes measured across multi-axial slices. The ratio of VAT to SAT is greater than 0.4, suggesting that individuals with SCI are at high risk of developing metabolic sequelae.
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Affiliation(s)
- Ashraf S. Gorgey
- Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA,Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA, USA,Correspondence to: Ashraf S. Gorgey, Department of Veterans Affairs, Hunter Holmes McGuire Medical Center, Physical Medicine and Rehabilitation, Spinal Cord Injury & Disorders Service, 1201 Broad Rock Blvd, Richmond, VA 23249, USA.
| | | | - Hunter J. Poarch
- Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA
| | - David R. Gater
- Spinal Cord Injury and Disorders Center, Hunter Holmes McGuire VAMC, Richmond, VA, USA,Department of Physical Medicine and Rehabilitation, Virginia Commonwealth University, Richmond, VA, USA
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22
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Regulation of abdominal adiposity by probiotics (Lactobacillus gasseri SBT2055) in adults with obese tendencies in a randomized controlled trial. Eur J Clin Nutr 2010; 64:636-43. [PMID: 20216555 DOI: 10.1038/ejcn.2010.19] [Citation(s) in RCA: 432] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND/OBJECTIVES In spite of the much evidence for the beneficial effects of probiotics, their anti-obesity effects have not been well examined. We evaluated the effects of the probiotic Lactobacillus gasseri SBT2055 (LG2055) on abdominal adiposity, body weight and other body measures in adults with obese tendencies. SUBJECTS/METHODS We conducted a multicenter, double-blind, randomized, placebo-controlled intervention trial. Subjects (n=87) with higher body mass index (BMI) (24.2-30.7 kg/m(2)) and abdominal visceral fat area (81.2-178.5 cm(2)) were randomly assigned to receive either fermented milk (FM) containing LG2055 (active FM; n=43) or FM without LG2055 (control FM; n=44), and were asked to consume 200 g/day of FM for 12 weeks. Abdominal fat area was determined by computed tomography. RESULTS In the active FM group, abdominal visceral and subcutaneous fat areas significantly (P<0.01) decreased from baseline by an average of 4.6% (mean (confidence interval): -5.8 (-10.0, -1.7) cm(2)) and 3.3% (-7.4 (-11.6, -3.1) cm(2)), respectively. Body weight and other measures also decreased significantly (P<0.001) as follows: body weight, 1.4% (-1.1 (-1.5, -0.7) kg); BMI, 1.5% (-0.4 (-0.5, -0.2) kg/m(2)); waist, 1.8% (-1.7 (-2.1, -1.4) cm); hip, 1.5% (-1.5 (-1.8, -1.1) cm). In the control group, by contrast, none of these parameters decreased significantly. High-molecular weight adiponectin in serum increased significantly (P<0.01) in the active and control groups by 12.7% (0.17 (0.07, 0.26) microg/ml) and 13.6% (0.23 (0.07, 0.38) microg/ml), respectively. CONCLUSION The probiotic LG2055 showed lowering effects on abdominal adiposity, body weight and other measures, suggesting its beneficial influence on metabolic disorders.
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Ortega FJ, Mayas D, Moreno-Navarrete JM, Catalán V, Gómez-Ambrosi J, Esteve E, Rodriguez-Hermosa JI, Ruiz B, Ricart W, Peral B, Fruhbeck G, Tinahones FJ, Fernández-Real JM. The gene expression of the main lipogenic enzymes is downregulated in visceral adipose tissue of obese subjects. Obesity (Silver Spring) 2010; 18:13-20. [PMID: 19543203 DOI: 10.1038/oby.2009.202] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Contradictory findings regarding the gene expression of the main lipogenic enzymes in human adipose tissue depots have been reported. In this cross-sectional study, we aimed to evaluate the mRNA expression of fatty acid synthase (FAS) and acetyl-CoA carboxilase (ACC) in omental and subcutaneous (SC) fat depots from subjects who varied widely in terms of body fat mass. FAS and ACC gene expression were evaluated by real time-PCR in 188 samples of visceral adipose tissue which were obtained during elective surgical procedures in 119 women and 69 men. Decreased sex-adjusted FAS (-59%) and ACC (-49%) mRNA were found in visceral adipose tissue from obese subjects, with and without diabetes mellitus type 2 (DM-2), compared with lean subjects (both P < 0.0001). FAS mRNA was also decreased (-40%) in fat depots from overweight subjects (P < 0.05). Indeed, FAS mRNA was significantly and positively associated with ACC gene expression (r = 0.316, P < 0.0001) and negatively with BMI (r = -0.274), waist circumference (r = -0.437), systolic blood pressure (r = -0.310), serum glucose (r = -0.277), and fasting triglycerides (r = -0.226), among others (all P < 0.0001). Similar associations were observed for ACC gene expression levels. In a representative subgroup of nonobese (n = 4) and obese women (n = 6), relative FAS gene expression levels significantly correlated (r = 0.657, P = 0.034; n = 10) with FAS protein values. FAS protein levels were also inversely correlated with blood glucose (r = -0.640, P = 0.046) and fasting triglycerides (r = -0.832, P = 0.010). In conclusion, the gene expression of the main lipogenic enzymes is downregulated in visceral adipose tissue from obese subjects.
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Affiliation(s)
- Francisco J Ortega
- Service of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomèdica de Girona (IdIBGi), Girona, Spain
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24
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Metabolic syndrome: A review of emerging markers and management. Diabetes & Metabolic Syndrome: Clinical Research & Reviews 2009. [DOI: 10.1016/j.dsx.2009.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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25
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Cartier A, Côté M, Lemieux I, Pérusse L, Tremblay A, Bouchard C, Després JP. Age-related differences in inflammatory markers in men: contribution of visceral adiposity. Metabolism 2009; 58:1452-8. [PMID: 19595381 DOI: 10.1016/j.metabol.2009.04.025] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Accepted: 04/07/2009] [Indexed: 11/26/2022]
Abstract
As visceral adipose tissue (AT) accumulation and inflammatory markers are known to increase with age, we examined whether this age-related change in regional AT distribution could contribute to the increase in the concentration of some inflammatory markers found with age. Two hundred eight healthy men aged 18.6 to 72.2 years and covering a wide range of adiposity values (body mass index, 18.5-39.3 kg/m(2)) were studied. Plasma C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) levels were measured by enzyme-linked immunosorbent assay. Anthropometric characteristics such as height, weight, and waist girth were measured; and body mass index was calculated. Cross-sectional areas of abdominal AT were obtained at L4-L5 by computed tomography. Fasting blood samples were collected to determine a complete lipoprotein lipid profile, and a 75-g oral glucose tolerance test was performed. Overall, visceral AT accumulation was positively correlated with age (r = 0.51, P < .0001) as well as with plasma CRP (r = 0.39, P < .0001), IL-6 (r = 0.32, P < .0001), and TNF-alpha (r = 0.14, P < .05) levels. A significant positive relationship was also observed between age and CRP (r = 0.36, P < .0001), IL-6 (r = 0.39, P < .0001), or TNF-alpha (r = 0.15, P < .05) concentrations. As middle-aged men were characterized by higher CRP (1.32 [25th percentile, 0.71; 75th percentile, 2.71] vs 0.66 [0.36, 1.62] mg/L, P < .0001) and IL-6 (1.60 [1.09, 2.28] vs 1.12 [0.77, 1.60] pg/mL, P < .0001) levels as well as by a greater amount of visceral AT (P < .0001) than young men, we have individually matched 43 young men (age, 28.6 +/- 5.82 years) with 43 middle-aged men (age, 57.6 +/- 5.15 years) on the basis of their visceral AT. Matching for visceral AT eliminated the difference between middle-aged men and younger adult men in inflammatory markers. These results suggest that the age-related variation in CRP and IL-6 is largely explained by differences in visceral AT.
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Affiliation(s)
- Amélie Cartier
- Centre de recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec, Québec (QC), Canada G1V 4G5
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26
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Lipolysis and lipid mobilization in human adipose tissue. Prog Lipid Res 2009; 48:275-97. [PMID: 19464318 DOI: 10.1016/j.plipres.2009.05.001] [Citation(s) in RCA: 505] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2009] [Revised: 05/04/2009] [Accepted: 05/08/2009] [Indexed: 01/04/2023]
Abstract
Triacylglycerol (TAG) stored in adipose tissue (AT) can be rapidly mobilized by the hydrolytic action of the three main lipases of the adipocyte. The non-esterified fatty acids (NEFA) released are used by other tissues during times of energy deprivation. Until recently hormone-sensitive lipase (HSL) was considered to be the key rate-limiting enzyme responsible for regulating TAG mobilization. A novel lipase named adipose triglyceride lipase/desnutrin (ATGL) has been identified as playing an important role in the control of fat cell lipolysis. Additionally perilipin and other proteins of the surface of the lipid droplets protecting or exposing the TAG core of the droplets to lipases are also potent regulators of lipolysis. Considerable progress has been made in understanding the mechanisms of activation of the various lipases. Lipolysis is under tight hormonal regulation. The best understood hormonal effects on AT lipolysis concern the opposing regulation by insulin and catecholamines. Heart-derived natriuretic peptides (i.e., stored in granules in the atrial and ventricle cardiomyocytes and exerting stimulating effects on diuresis and natriuresis) and numerous autocrine/paracrine factors originating from adipocytes and other cells of the stroma-vascular fraction may also participate in the regulation of lipolysis. Endocrine and autocrine/paracrine factors cooperate and lead to a fine regulation of lipolysis in adipocytes. Age, anatomical site, sex, genotype and species differences all play a part in the regulation of lipolysis. The manipulation of lipolysis has therapeutic potential in the metabolic disorders frequently associated with obesity and probably in several inborn errors of metabolism.
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27
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Cassis LA, Police SB, Yiannikouris F, Thatcher SE. Local adipose tissue renin-angiotensin system. Curr Hypertens Rep 2008; 10:93-8. [PMID: 18474174 DOI: 10.1007/s11906-008-0019-9] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A local renin-angiotensin system (RAS) has been proposed in adipocytes. Adipocytes are a suggested source of components of the RAS, with regulation of their production related to obesity-hypertension. Both angiotensin type 1 and 2 receptors have been localized to adipocytes. Angiotensin II has been demonstrated to regulate adipocyte growth and differentiation, lipid metabolism, and expression and release of adipokines and RAS components, and to promote oxidative stress. Differences in regional expression of RAS components in visceral versus subcutaneous adipose tissue have been suggested as a link between abdominal obesity and cardiovascular disease. Finally, several studies support antihypertensive efficacy of RAS blockade in patients with type 2 diabetes and obesity. Future studies should address the role of adipocyte-specific deficiency of RAS components to definitively determine the relevance of the adipose RAS to normal physiology and to the development of hypertension.
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Affiliation(s)
- Lisa A Cassis
- Graduate Center for Nutritional Sciences, Wethington Building, Room 521b, 900 South Limestone Street, University of Kentucky, Lexington, KY 40536-0200, USA.
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28
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Levine JA, Davis RM. The Pol-e-pill finally arrives. Diabetes 2008; 57:1784-5. [PMID: 18586910 PMCID: PMC2453630 DOI: 10.2337/db08-0108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 01/27/2008] [Indexed: 11/13/2022]
Affiliation(s)
- James A Levine
- Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota, USA.
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Bays HE, González-Campoy JM, Bray GA, Kitabchi AE, Bergman DA, Schorr AB, Rodbard HW, Henry RR. Pathogenic potential of adipose tissue and metabolic consequences of adipocyte hypertrophy and increased visceral adiposity. Expert Rev Cardiovasc Ther 2008; 6:343-68. [PMID: 18327995 DOI: 10.1586/14779072.6.3.343] [Citation(s) in RCA: 334] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
When caloric intake exceeds caloric expenditure, the positive caloric balance and storage of energy in adipose tissue often causes adipocyte hypertrophy and visceral adipose tissue accumulation. These pathogenic anatomic abnormalities may incite metabolic and immune responses that promote Type 2 diabetes mellitus, hypertension and dyslipidemia. These are the most common metabolic diseases managed by clinicians and are all major cardiovascular disease risk factors. 'Disease' is traditionally characterized as anatomic and physiologic abnormalities of an organ or organ system that contributes to adverse health consequences. Using this definition, pathogenic adipose tissue is no less a disease than diseases of other body organs. This review describes the consequences of pathogenic fat cell hypertrophy and visceral adiposity, emphasizing the mechanistic contributions of genetic and environmental predispositions, adipogenesis, fat storage, free fatty acid metabolism, adipocyte factors and inflammation. Appreciating the full pathogenic potential of adipose tissue requires an integrated perspective, recognizing the importance of 'cross-talk' and interactions between adipose tissue and other body systems. Thus, the adverse metabolic consequences that accompany fat cell hypertrophy and visceral adiposity are best viewed as a pathologic partnership between the pathogenic potential adipose tissue and the inherited or acquired limitations and/or impairments of other body organs. A better understanding of the physiological and pathological interplay of pathogenic adipose tissue with other organs and organ systems may assist in developing better strategies in treating metabolic disease and reducing cardiovascular disease risk.
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Affiliation(s)
- Harold E Bays
- L-MARC Research Center, 3288 Illinois Avenue, Louisville, KY 40213, USA.
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30
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Abstract
The importance of adipose tissue in health as well as disease has been demonstrated in several studies recently, and it has become appropriate to use the term 'adipose organ' when referring to adipose tissue as a whole. The obesity epidemic, with a marked increase in the incidence of the metabolic syndrome leading to diabetes type 2 as well as cardiovascular complications, has stimulated considerable interest in adipose tissue biology. Moreover, several studies in different species have shown that limited energy intake is associated with less inflammation, improved biomarkers of health and a marked increase in longevity. In addition, there is convincing evidence that an optimal amount of adipose tissue is essential for many body functions such as immune response, reproduction and bone quality. Some nutrients and their metabolites are important as energy sources as well as ligands for many transcription factors expressed in adipose tissue, including all energy-providing nutrients both directly and indirectly as well as cholesterol, vitamin E and vitamin D. In particular, fatty acids can be effectively taken up by adipocytes and they can interact with several transcription factors crucial for growth, development and metabolic response, e.g. PPARalpha, -delta and -gamma, sterol regulatory element-binding proteins1 and 2 and liver X receptors alpha and beta). Moreover, glucose is also readily taken up and stored as fatty acids via lipogenesis in adipocytes. It is known that some metabolic signals released as proteins from adipose tissue (adipokines) are important for normal as well as pathological responses to the amount of energy stored in the adipose organ. The future challenge will be to understand the function of adipose tissue in energy homeostasis and the interplay with nutrients in order to be able to give optimal advice for the prevention and treatment of obesity.
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Affiliation(s)
- Fred Haugen
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, PO Box 1046, Blindern, 0316 Oslo, Norway
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31
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Sharma AM, Staels B. Review: Peroxisome proliferator-activated receptor gamma and adipose tissue--understanding obesity-related changes in regulation of lipid and glucose metabolism. J Clin Endocrinol Metab 2007; 92:386-95. [PMID: 17148564 DOI: 10.1210/jc.2006-1268] [Citation(s) in RCA: 360] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
CONTEXT Adipose tissue is a metabolically dynamic organ, serving as a buffer to control fatty acid flux and a regulator of endocrine function. In obese subjects, and those with type 2 diabetes or the metabolic syndrome, adipose tissue function is altered (i.e. adipocytes display morphological differences alongside aberrant endocrine and metabolic function and low-grade inflammation). EVIDENCE ACQUISITION Articles on the role of peroxisome proliferator-activated receptor gamma (PPARgamma) in adipose tissue of healthy individuals and those with obesity, metabolic syndrome, or type 2 diabetes were sourced using MEDLINE (1990-2006). EVIDENCE SYNTHESIS Articles were assessed to provide a comprehensive overview of how PPARgamma-activating ligands improve adipose tissue function, and how this links to improvements in insulin resistance and the progression to type 2 diabetes and atherosclerosis. CONCLUSIONS PPARgamma is highly expressed in adipose tissue, where its activation with thiazolidinediones alters fat topography and adipocyte phenotype and up-regulates genes involved in fatty acid metabolism and triglyceride storage. Furthermore, PPARgamma activation is associated with potentially beneficial effects on the expression and secretion of a range of factors, including adiponectin, resistin, IL-6, TNFalpha, plasminogen activator inhibitor-1, monocyte chemoattractant protein-1, and angiotensinogen, as well as a reduction in plasma nonesterified fatty acid supply. The effects of PPARgamma also extend to macrophages, where they suppress production of inflammatory mediators. As such, PPARgamma activation appears to have a beneficial effect on the relationship between the macrophage and adipocyte that is distorted in obesity. Thus, PPARgamma-activating ligands improve adipose tissue function and may have a role in preventing progression of insulin resistance to diabetes and endothelial dysfunction to atherosclerosis.
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Affiliation(s)
- Arya M Sharma
- Canada Research Chair for Cardiovascular Obesity Research and Management, McMaster University, Hamilton General Hospital, 237 Barton Street East, Hamilton, Ontario, Canada L8L 2X2.
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Gesta S, Blüher M, Yamamoto Y, Norris AW, Berndt J, Kralisch S, Boucher J, Lewis C, Kahn CR. Evidence for a role of developmental genes in the origin of obesity and body fat distribution. Proc Natl Acad Sci U S A 2006; 103:6676-81. [PMID: 16617105 PMCID: PMC1458940 DOI: 10.1073/pnas.0601752103] [Citation(s) in RCA: 443] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Obesity, especially central obesity, is a hereditable trait associated with a high risk for development of diabetes and metabolic disorders. Combined gene expression analysis of adipocyte- and preadipocyte-containing fractions from intraabdominal and subcutaneous adipose tissue of mice revealed coordinated depot-specific differences in expression of multiple genes involved in embryonic development and pattern specification. These differences were intrinsic and persisted during in vitro culture and differentiation. Similar depot-specific differences in expression of developmental genes were observed in human subcutaneous versus visceral adipose tissue. Furthermore, in humans, several genes exhibited changes in expression that correlated closely with body mass index and/or waist/hip ratio. Together, these data suggest that genetically programmed developmental differences in adipocytes and their precursors in different regions of the body play an important role in obesity, body fat distribution, and potential functional differences between internal and subcutaneous adipose tissue.
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Affiliation(s)
- Stephane Gesta
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
| | - Matthias Blüher
- Department of Internal Medicine III, University of Leipzig, 04103 Leipzig, Germany
| | - Yuji Yamamoto
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
| | - Andrew W. Norris
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
| | - Janin Berndt
- Department of Internal Medicine III, University of Leipzig, 04103 Leipzig, Germany
| | - Susan Kralisch
- Department of Internal Medicine III, University of Leipzig, 04103 Leipzig, Germany
| | - Jeremie Boucher
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
| | - Choy Lewis
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
| | - C. Ronald Kahn
- *Joslin Diabetes Center and Harvard Medical School, Boston, MA 02215; and
- To whom correspondence should be addressed at:
Joslin Diabetes Center, One Joslin Place, Boston, MA 02215. E-mail:
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Abstract
The primary function of adipose tissue is to store energy in the form of triglycerides during periods of energy excess and to release the energy during fasting or starvation as free fatty acids and glycerol. Adipose tissue secretes a variety of peptides called adipocytokines (eg, leptin, adiponectin, tumor necrosis factor-alpha, interleukin-6, resistin, visfatin) that have endocrine, autocrine, and paracrine effects on the brain, liver, and skeletal muscles. These peptides play an important role in the regulation of energy homeostasis and intermediary metabolism. Adipose tissue also aromatizes androgens to estrogens, and some adipose tissue depots (mechanical fat) serve a protective or cushioning function. Dysfunction of adipose tissue can result in insulin resistance and its metabolic complications in patients with excess body fat (obesity) or markedly reduced body fat (lipodystrophy). Alterations in free fatty acid and adipocytokine release from adipose tissue may underlie metabolic complications.
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Affiliation(s)
- Abhimanyu Garg
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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Hermanowski-Vosatka A, Balkovec JM, Cheng K, Chen HY, Hernandez M, Koo GC, Le Grand CB, Li Z, Metzger JM, Mundt SS, Noonan H, Nunes CN, Olson SH, Pikounis B, Ren N, Robertson N, Schaeffer JM, Shah K, Springer MS, Strack AM, Strowski M, Wu K, Wu T, Xiao J, Zhang BB, Wright SD, Thieringer R. 11beta-HSD1 inhibition ameliorates metabolic syndrome and prevents progression of atherosclerosis in mice. ACTA ACUST UNITED AC 2005; 202:517-27. [PMID: 16103409 PMCID: PMC2212859 DOI: 10.1084/jem.20050119] [Citation(s) in RCA: 299] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The enzyme 11β–hydroxysteroid dehydrogenase (HSD) type 1 converts inactive cortisone into active cortisol in cells, thereby raising the effective glucocorticoid (GC) tone above serum levels. We report that pharmacologic inhibition of 11β-HSD1 has a therapeutic effect in mouse models of metabolic syndrome. Administration of a selective, potent 11β-HSD1 inhibitor lowered body weight, insulin, fasting glucose, triglycerides, and cholesterol in diet-induced obese mice and lowered fasting glucose, insulin, glucagon, triglycerides, and free fatty acids, as well as improved glucose tolerance, in a mouse model of type 2 diabetes. Most importantly, inhibition of 11β-HSD1 slowed plaque progression in a murine model of atherosclerosis, the key clinical sequela of metabolic syndrome. Mice with a targeted deletion of apolipoprotein E exhibited 84% less accumulation of aortic total cholesterol, as well as lower serum cholesterol and triglycerides, when treated with an 11β-HSD1 inhibitor. These data provide the first evidence that pharmacologic inhibition of intracellular GC activation can effectively treat atherosclerosis, the key clinical consequence of metabolic syndrome, in addition to its salutary effect on multiple aspects of the metabolic syndrome itself.
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Abstract
Adipose tissue actively participates in regulation of food intake, energy expenditure, fuel metabolism, and a variety of other physiologic processes through its endocrine, paracrine, and autocrine secretory products (Table 4). Abnormal synthesis of these secretory products may be related to the pathogenesis of insulin resistance and its complications in patients who have adipose tissue disorders, such as obesity and lipodvstrophies.
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Affiliation(s)
- Wasim A Haque
- Division of Nutrition and Metabolic Diseases, Department of Internal Medicine, Center for Human Nutrition, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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36
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Agarwal AK. Cortisol metabolism and visceral obesity: role of 11beta-hydroxysteroid dehydrogenase type I enzyme and reduced co-factor NADPH. Endocr Res 2003; 29:411-8. [PMID: 14682470 DOI: 10.1081/erc-120026947] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Several factors including genetic and environmental play a role in the development of obesity and the metabolic syndrome. The transgenic mouse overexpressing 11beta-hydroxysteroid dehydrogenase (11beta-HSD) develops visceral obesity. However, it remains unclear how a ubiquitously expressed 11beta-HSD1 enzyme affects adipose tissue so much that it would lead to obesity. In this commentary we explore the possibility that increased intracellular availability of reduced co-factor, NADPH, could exacerbate the enzymatic activity.
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Affiliation(s)
- Anil K Agarwal
- Division of Nutrition and Metabolic Diseases, Department of Internal Medicine, Center for Human Nutrition, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
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37
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Affiliation(s)
- Muredach P Reilly
- Cardiovascular Division, Department of Medicine, the Center for Experimental Therapeutics and the Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania School of Medicine, Philadelphia, Penn 19104-6160, USA
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38
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Giusti V, Verdumo C, Suter M, Gaillard RC, Burckhardt P, Pralong F. Expression of peroxisome proliferator-activated receptor-gamma1 and peroxisome proliferator-activated receptor-gamma2 in visceral and subcutaneous adipose tissue of obese women. Diabetes 2003; 52:1673-6. [PMID: 12829631 DOI: 10.2337/diabetes.52.7.1673] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Data regarding the expression of peroxisome proliferator-activated receptor (PPAR)-gamma(1) and PPAR-gamma(2) in human visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) are conflicting. To clarify this issue, we studied 50 women who had a BMI >35 kg/m(2) were undergoing gastric reduction surgery. Phenotyping included recording of anthropometric parameters and of a biological profile. Quantification of the expression of PPAR-gamma(1) and PPAR-gamma(2) in samples of VAT and SAT was performed by real-time RT-PCR. In both SAT and VAT, the level of expression of PPAR-gamma(2) were >20-fold that of PPAR-gamma(1) (P < 0.001 for both). However, only PPAR-gamma(1) was differentially expressed, its levels in SAT being 216 +/- 34% those in VAT (P < 0.001). In a stepwise, multivariate regression analysis, the levels of PPAR-gamma(1) in both SAT and VAT were the major determinants of waist circumference (R(2) = 21% for both; P < 0.01). Finally, leptin but not PPARs appeared as the single parameter explaining the largest part of the variability of BMI in our cohort of patients (R(2) = 22%, P < 0.001). These results are consistent with the putative roles of PPAR-gamma(1) and PPAR-gamma(2) in carbohydrate metabolism and energy homeostasis, respectively. As such, they constitute an important step toward the identification of potential targets for novel therapeutic strategies in the fields of obesity.
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Affiliation(s)
- Vittorio Giusti
- Department of Internal Medicine, Diabetology and Metabolism, Centre Hospitalier Universitaire, Vaudois, Lausanne, Switzerland.
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39
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Weber N, Klein E, Mukherjee KD. Stereospecific incorporation of palmitoyl, oleoyl and linoleoyl moieties into adipose tissue triacylglycerols of rats results in constant sn-1:sn-2:sn-3 in rats fed rapeseed, olive, conventional or high oleic sunflower oils, but not in those fed coriander oil. J Nutr 2003; 133:435-41. [PMID: 12566480 DOI: 10.1093/jn/133.2.435] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We report the stereospecific (sn-1, sn-2, sn-3) distribution of fatty acids in subcutaneous adipose tissue triacylglycerols of male weaned Wistar rats fed either a standard diet or diets containing, in addition to 20 g corn oil/kg feed, 120 g/kg feed, each, of canola-type rapeseed oil, olive oil, conventional or high oleic sunflower oil or high petroselinic coriander oil for 10 wk. The regiospecific distribution of the major acyl moieties in the sn-1 (3) vs. sn-2 positions of the adipose tissue triacylglycerols broadly reflected that of the dietary oils. The saturated palmitoyl and stearoyl moieties were more abundant in the sn-1 and sn-3 positions compared with the sn-2 position of the adipose tissue triacylglycerols, and both occurred at a higher proportion in the sn-1 than in the sn-3 position. Oleoyl moieties were abundant in all the three positions of the adipose tissue triacylglycerols, whereas petroselinoyl moieties were more abundant in the sn-1 and sn-3 positions compared with the sn-2 position. Linoleoyl moieties occurred predominantly in the sn-2 position compared with the sn-1 and sn-3 positions of the adipose tissue triacylglycerols; however, they were more abundant in the sn-3 than in the sn-1 position. Despite widely varying proportions of the palmitoyl, oleoyl and linoleoyl moieties at the three positions of the dietary triacylglycerols, the ratios of each of these acyl moieties at the sn-1, sn-2, and sn-3 positions in adipose tissue triacylglycerols were essentially constant for all groups, with the exception of the group fed coriander oil, indicating a rigid stereospecific incorporation.
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Affiliation(s)
- Nikolaus Weber
- Institute for Lipid Research, Federal Centre for Cereal, Potato and Lipid Research, D-48147 Münster, Germany.
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40
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Thomas EL, Bell JD. Influence of undersampling on magnetic resonance imaging measurements of intra-abdominal adipose tissue. Int J Obes (Lond) 2003; 27:211-8. [PMID: 12587001 DOI: 10.1038/sj.ijo.802229] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Single-slice magnetic resonance imaging (MRI) and computed tomography (CT) are finding increasing use as methods to estimate visceral fat content in human studies. To assess the validity of this approach, we have compared single- and multi-slice MRI methods for the measurement of intra-abdominal adipose tissue content. MEASUREMENTS Multi-slice whole-body MR images and single-slices at the level of L2-L3 and L4-L5 were obtained from 59 healthy female volunteers chosen to cover a wide range of body size, and from 17 healthy female volunteers before and after a 6-month exercise intervention. RESULTS Taking the group as a whole, significant correlation between multi-slice and single-slices was observed (L2-L3: r=0.56; P<0.01; L4-L5: r=0.76; P<0.01). However, the ranking of subjects according to their intra-abdominal fat content was significantly altered by the choice of MRI strategy, especially using L2-L3 methodology. Whole-body (-23.8+/-20.0%; P<0.01) and single-slice (L2-L3: -31.03+/-35.0%; P<0.01; L4-L5: -22.1+/-37.24%; p<0.05) MRI methods also detected a significant decrease in intra-abdominal fat following the exercise protocol, although the latter techniques gave rise to increased spreading of the data from the mean. These results suggest that the use of single-slice imaging techniques can lead to inconsistencies in the estimation of intra-abdominal fat content, which in turn can have significant effects on data interpretation. CONCLUSION Single-slice MRI appears to be suitable for assessing changes in intra-abdominal fat content in interventional studies, especially in large cohort of subjects, where each subject can serve as its own control. However, for accurate determination of an individual's intra-abdominal fat content, and intersubject comparison, only multi-slice imaging will give precise results.
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Affiliation(s)
- E L Thomas
- The Robert Steiner MR Unit, MRC Clinical Sciences Centre, Hammersmith Hospital, Imperial College of Medicine, London, UK.
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41
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Miyatake N, Nishikawa H, Morishita A, Kunitomi M, Wada J, Suzuki H, Takahashi K, Makino H, Kira S, Fujii M. Daily walking reduces visceral adipose tissue areas and improves insulin resistance in Japanese obese subjects. Diabetes Res Clin Pract 2002; 58:101-7. [PMID: 12213351 DOI: 10.1016/s0168-8227(02)00129-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE It is known that the accumulation of abdominal fat is one of the risk factors for atherosclerosis. Although exercise is commonly prescribed to reduce body weight, the efficacy of low intensity exercise for the reduction of abdominal visceral adipose tissue remains to be investigated. RESEARCH DESIGN AND METHODS Thirty one obese Japanese males (body mass index (BMI) > or = 25) ranging in age from 32 to 59, participated in a 1-year follow up study and they were instructed to have a modest increase in daily activity and record their daily walking. Before and after exercise prescription, body composition, blood pressure, physical fitness i.e. aerobic exercise level, muscle strength and flexibility were recorded. Insulin resistance was evaluated using a homeostasis model assessment, the HOMA index. RESULTS HOMA index, parameters of body composition, blood pressure, triglyceride and HDL cholesterol were significantly improved. The aerobic exercise level, leg strength, weight-bearing index (leg strength/body weight) and the steps taken per day were significantly increased. By stepwise multiple regression analysis, Delta visceral adipose tissue area was the major determinant for Delta HOMA index. (Delta HOMA index=-0.386+0.016 Delta visceral adipose tissue area, r2=0.267, P<0.01). Exercise capacity and calorie intake were not significantly related to Delta visceral adipose tissue area, while Delta steps per day was significantly correlated with Delta visceral adipose tissue area (Delta visceral adipose tissue area=-21.363-0.004 Delta steps per day, r2=0.184, P=0.0326). CONCLUSIONS Taken together, intra-abdominal visceral adipose tissue is critically involved in insulin resistance and daily walking rather than improvement of exercise capacity correlated with the reduction of visceral adipose tissue in obese Japanese males.
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Affiliation(s)
- Nobuyuki Miyatake
- Okayama Southern Institute of Health, 408-1 Hirata, 700-0952 Okayama, Japan.
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42
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Okura T, Tanaka K, Nakanishi T, Lee DJ, Nakata Y, Wee SW, Shimokata H. Effects of obesity phenotype on coronary heart disease risk factors in response to weight loss. OBESITY RESEARCH 2002; 10:757-66. [PMID: 12181384 DOI: 10.1038/oby.2002.103] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To determine whether there is a difference in risk-factor improvement for coronary heart disease (CHD) between the intra-abdominal fat (IF) and subcutaneous fat (SF) obesity phenotypes after weight loss. RESEARCH METHODS AND PROCEDURES Subjects included 55 mildly obese women (body mass index, 25 to 36 kg/m(2); age range, 34 to 63 years) who had at least two of three CHD risk factors [systolic blood pressure (SBP), >140 mm Hg; total cholesterol (TC), >220 mg/dL; fasting plasma glucose, >110 mg/dL). Using computed tomography, IF obesity was classified as > or =110 cm(2) of the IF area measured; subjects with <110 cm(2) were classified as having SF obesity. The IF and SF obesity groups were divided into diet-only and diet-plus-exercise groups. Assays and measurements were performed before and after a 14-week (98-day) intervention. RESULTS Weight was reduced by 7 to 10 kg in each group. The IF and SF areas, SBP, diastolic blood pressure, TC, and low-density lipoprotein-cholesterol were significantly reduced in all groups (p < 0.01). Reduction in IF area was greater in IF obesity than in SF obesity, whereas no differences were observed in the improvement of CHD risk factors. Sample sizes needed for observing a significant difference for SBP, TC, triglycerides, and fasting plasma glucose were greater than the number of subjects in this study. DISCUSSION Our results suggest that the influence of the obesity phenotype on improving CHD risk factors is not apparent. A larger study is needed to prove the validity of this finding.
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Affiliation(s)
- Tomohiro Okura
- Department of Epidemiology, National Institute for Longevity Sciences, Obu, Japan.
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43
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Weber N, Klein E, Mukherjee KD. The composition of the major molecular species of adipose tissue triacylglycerols of rats reflects those of dietary rapeseed, olive and sunflower oils. J Nutr 2002; 132:726-32. [PMID: 11925468 DOI: 10.1093/jn/132.4.726] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We report the composition of constituent fatty acids and molecular species of adipose tissue triacylglycerols of male weaned Wistar rats fed diets containing, in addition to 20 g corn oil/kg feed, 120 g per kg feed canola-type rapeseed oil, olive oil or conventional sunflower oil for 10 wk. The composition of fatty acids and molecular species of the triacylglycerols of subcutaneous, epididymal and perirenal adipose tissues did not differ among groups (P > 0.01), broadly reflecting the corresponding compositions of the dietary oils. The major molecular species of dietary triacylglycerols, especially trioleoylglycerol (OOO) and linoleoyl-dioleoylglycerols (LOO) in the rapeseed oil and olive oil diets, dioleoyl-palmitoylglycerols (OOP) in the olive oil diet, dilinoleoyl-oleoylglycerols (LLO) in the rapeseed oil and sunflower oil diets, and dilinoleoyl-palmitoylglycerols (LLP), linoleoyl-oleoyl-palmitoylglycerols (LOP) as well as trilinoleoylglycerol (LLL) in the sunflower oil diet were also prominent constituents of the corresponding adipose tissue triacylglycerols. On the other hand, predominant molecular species containing alpha-linolenoyl (Ln) moieties, e.g., alpha-linolenoyl-linoleoyl-oleoylglycerols (LnLO) and alpha -linolenoyl-dioleoylglycerols (LnOO) from the rapeseed oil diet were not prominent constituents of rat adipose tissue triacylglycerols, whereas LOP from rapeseed oil and olive oil diets and OOP from rapeseed oil and sunflower oil diets were distinctly enriched in the corresponding adipose tissues. Most of the minor molecular species of the dietary triacylglycerols from all the three diets were distinctly present in the corresponding adipose tissues. Thus, despite numerous biochemical processes involved in the metabolism of dietary triacylglycerols, a substantial proportion of the molecular species of adipose tissue triacylglycerols containing linoleoyl (L), oleoyl (O) and palmitoyl (P) moieties resemble those of dietary triacylglycerols.
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Affiliation(s)
- Nikolaus Weber
- Institut für Biochemie und Technologie der Fette, H. P. Kaufmann-Institut, BAGKF, D-48147 Münster, Germany.
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44
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Iemura A, Douchi T, Yamamoto S, Yoshimitsu N, Nagata Y. Body fat distribution as a risk factor of endometrial cancer. J Obstet Gynaecol Res 2000; 26:421-5. [PMID: 11152327 DOI: 10.1111/j.1447-0756.2000.tb01352.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To investigate the relative contributions of upper body fat distribution and overall adiposity to endometrial cancer risk. METHODS Subjects were 63 postmenopausal women with endometrial cancer aged less than 70 years and 201 age-matched controls. Age, age at menopause, years since menopause, height, weight, and body mass index were recorded at the time of admission. The trunk-leg fat ratio, body fat mass, trunk fat mass, and the percentage of body fat were measured by dual-energy X-ray absorptiometry. RESULTS Trunk-leg fat ratio was higher in endometrial cancer patients than in controls (1.40 +/- 0.59 vs 1.23 +/- 0.39, p < 0.05). Whereas, other variables including age at menopause, percentage of body fat, body fat mass, and body mass index did not differ between the 2 groups. On stepwise multiple regression analysis, the trunk-leg fat ratio was still correlated with the presence of endometrial cancer (p < 0.05). CONCLUSIONS Upper body fat distribution rather than overall adiposity is associated with endometrial cancer risk.
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Affiliation(s)
- A Iemura
- Department of Obstetrics and Gynecology, Faculty of Medicine, Kagoshima University, Japan
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45
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Behrens GM, Stoll M, Schmidt RE. Lipodystrophy syndrome in HIV infection: what is it, what causes it and how can it be managed? Drug Saf 2000. [PMID: 10915032 DOI: 10.2165/00002018-200023010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Since the introduction of HIV-1 protease inhibitors as components of antiretroviral drug combination regimens, the clinical course of HIV disease and opportunistic infections has changed dramatically. Besides the favourable virological, immunological and clinical impact of highly active antiretroviral therapy (HAART), several adverse drug reactions have been observed in patients with HIV receiving therapy. Particularly, peripheral lipodystrophy, central adiposity, dyslipidaemia and insulin resistance have been described with a prevalence of up to 80% in patients infected with HIV, and attributed to almost all components of HAART. Hyperlipidaemia is characterised by an increase of low and very low density lipoprotein-cholesterol as well as apolipoproteins B and E. Several studies strongly suggest that there are either multiple syndromes or a variety of factors inducing different changes that influence the ultimate phenotype. Similarities between HIV-associated fat redistribution and metabolic abnormalities with both inherited lipodystrophies and benign symmetric lipomatosis suggest the pathophysiological involvement of, for example, nuclear factors like lamin A/C and drug-induced mitochondrial dysfunction. Moreover, there is some evidence that cytokines and hormones impair fat and glucose homeostasis in patients with HIV receiving HAART. Three years after the first description of HIV therapy-associated abnormal fat redistribution, there is still an ongoing discussion about the case definition, diagnostic procedure and treatment options for both body shape changes and metabolic disturbances. Regarding therapy, there is a major concern about possible complex pharmacological interactions and overlapping adverse effects between HAART and, for example, lipid-lowering therapy. In addition, the likely contribution of both nucleoside analogue reverse transcriptase inhibitors and protease inhibitors to the development of abnormal fat redistribution in patients with HIV limits options of changing to alternative effective antiretroviral drug combinations. Thus, the occurrence of hyperlipidaemia, maturity onset diabetes mellitus, and marked changes in body habitus resulted in important social and clinical consequences such as an increased risk of atherosclerosis. It also sheds new light on the use of protease inhibitors regarding risk factors for the initial treatment decision. In this article, we discuss the features, pathogenesis and treatment options for body fat redistribution and metabolic disturbances associated with HAART in HIV-1 infection.
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Affiliation(s)
- G M Behrens
- Department for Clinical Immunology, Hannover Medical School, Germany.
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46
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Martínez E, García-Viejo MA, Blanco JL, Bianchi L, Buira E, Conget I, Casamitjana R, Mallolas J, Gatell JM. Impact of switching from human immunodeficiency virus type 1 protease inhibitors to efavirenz in successfully treated adults with lipodystrophy. Clin Infect Dis 2000; 31:1266-73. [PMID: 11073762 DOI: 10.1086/317426] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2000] [Revised: 04/10/2000] [Indexed: 11/03/2022] Open
Abstract
We prospectively followed 20 consecutive patients with human immunodeficiency virus type 1 (HIV-1) with viral loads of <200 RNA copies/mL. These patients had been treated with 2 nucleoside reverse transcriptase inhibitors and > or =1 HIV-1 protease inhibitor for > or =3 months; they developed body changes consistent with lipodystrophy and requested they be switched from protease inhibitor to efavirenz. At baseline and every 3 months, we assessed the following: body mass index, waist-to-hip ratio, regional fat thickness (assessed by sonography), fasting total and high-density lipoprotein cholesterol, triglycerides, glucose, insulin, CD4(+) cells, and viral load. At baseline, hypertriglyceridemia (> or =200 mg/dL) was present in 17 (85%) patients, hypercholesterolemia (> or =200 mg/dL) in 14 (70%), and impaired fasting glucose (> or =110 mg/dL) in 8 (40%); CD4(+) T cells were 280x10(6) cells/L (range, 64-942x10(6) cells/L). HIV-1 RNA had been at <200 copies/mL for a median of 14 months (range, 3-24 months). Six months after switching to efavirenz, there was a reduction in triglyceride levels (a decrease of 31%; P=.03) and fasting insulin resistance index (a decrease of 28%; P=.03), but total and high-density lipoprotein cholesterol and glucose did not change. Waist-to-hip ratio decreased from 0.92 to 0.87 (P=.06). Subcutaneous fat thickness did not change. CD4(+) cells remained stable (363x10(6) cells/L; range, 102-741x10(6) cells/L; P=.65). Nineteen patients (95%) had HIV-1 RNA levels that remained at <200 copies/mL. Although CD4(+) response and viral suppression remained preserved after 6 months of switching from protease inhibitor to efavirenz, the benefits of this approach on the evolution of lipodystrophy were limited, and our findings do not support its routine recommendation to treat lipodystrophy.
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Affiliation(s)
- E Martínez
- Infectious Diseases Unit, Hospital Clínic, 08036 Barcelona, Spain.
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47
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Behrens GM, Stoll M, Schmidt RE. Lipodystrophy syndrome in HIV infection: what is it, what causes it and how can it be managed? Drug Saf 2000; 23:57-76. [PMID: 10915032 DOI: 10.2165/00002018-200023010-00004] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Since the introduction of HIV-1 protease inhibitors as components of antiretroviral drug combination regimens, the clinical course of HIV disease and opportunistic infections has changed dramatically. Besides the favourable virological, immunological and clinical impact of highly active antiretroviral therapy (HAART), several adverse drug reactions have been observed in patients with HIV receiving therapy. Particularly, peripheral lipodystrophy, central adiposity, dyslipidaemia and insulin resistance have been described with a prevalence of up to 80% in patients infected with HIV, and attributed to almost all components of HAART. Hyperlipidaemia is characterised by an increase of low and very low density lipoprotein-cholesterol as well as apolipoproteins B and E. Several studies strongly suggest that there are either multiple syndromes or a variety of factors inducing different changes that influence the ultimate phenotype. Similarities between HIV-associated fat redistribution and metabolic abnormalities with both inherited lipodystrophies and benign symmetric lipomatosis suggest the pathophysiological involvement of, for example, nuclear factors like lamin A/C and drug-induced mitochondrial dysfunction. Moreover, there is some evidence that cytokines and hormones impair fat and glucose homeostasis in patients with HIV receiving HAART. Three years after the first description of HIV therapy-associated abnormal fat redistribution, there is still an ongoing discussion about the case definition, diagnostic procedure and treatment options for both body shape changes and metabolic disturbances. Regarding therapy, there is a major concern about possible complex pharmacological interactions and overlapping adverse effects between HAART and, for example, lipid-lowering therapy. In addition, the likely contribution of both nucleoside analogue reverse transcriptase inhibitors and protease inhibitors to the development of abnormal fat redistribution in patients with HIV limits options of changing to alternative effective antiretroviral drug combinations. Thus, the occurrence of hyperlipidaemia, maturity onset diabetes mellitus, and marked changes in body habitus resulted in important social and clinical consequences such as an increased risk of atherosclerosis. It also sheds new light on the use of protease inhibitors regarding risk factors for the initial treatment decision. In this article, we discuss the features, pathogenesis and treatment options for body fat redistribution and metabolic disturbances associated with HAART in HIV-1 infection.
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Affiliation(s)
- G M Behrens
- Department for Clinical Immunology, Hannover Medical School, Germany.
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48
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Thomas EL, Brynes AE, McCarthy J, Goldstone AP, Hajnal JV, Saeed N, Frost G, Bell JD. Preferential loss of visceral fat following aerobic exercise, measured by magnetic resonance imaging. Lipids 2000; 35:769-76. [PMID: 10941878 DOI: 10.1007/s11745-000-0584-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The aim of this study was to use whole-body magnetic resonance imaging (MRI) together with biochemical and anthropometric measurements to study the influence of regular moderate exercise with no dietary intervention on adipose tissue distribution in nonobese healthy women. We found significant decreases in both total (28.86+/-2.24 vs. 27.00+/-2.27 liters, P < 0.05) and regional fat depots (visceral fat: 1.68+/-0.21 vs. 1.26+/-0.18 liters, P < 0.01) using whole-body MRI despite no significant change in body weight, body mass index, or the waist-to-hip ratio. Interestingly, no changes in body fat content were found using anthropometry or impedance. There was a significant increase in high density lipoprotein cholesterol (1.58+/-0.06 vs. 1.66+/-0.08 mmol/L P < 0.02) following exercise although there were no changes in other blood lipids such as triglycerides. In summary, moderate aerobic exercise over a period of 6 mon resulted in a preferential loss in visceral fat in nonobese healthy women, and this may help to explain some of the health benefits associated with regular and moderate physical activity.
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Affiliation(s)
- E L Thomas
- The Robert Steiner MR Unit, MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London, England.
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Elbers JM, de Jong S, Teerlink T, Asscheman H, Seidell JC, Gooren LJ. Changes in fat cell size and in vitro lipolytic activity of abdominal and gluteal adipocytes after a one-year cross-sex hormone administration in transsexuals. Metabolism 1999; 48:1371-7. [PMID: 10582544 DOI: 10.1016/s0026-0495(99)90146-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We prospectively studied the effects of cross-sex hormone administration on fat cell size and in vitro lipolytic activity in subcutaneous abdominal and gluteal fat biopsies obtained from 19 male-to-female (M-F) transsexuals and 17 female-to-male (F-M) transsexuals. The amount of subcutaneous fat at the abdominal and gluteal levels was quantified with the use of magnetic resonance imaging (MRI). Before cross-sex hormone administration, M-F transsexuals had less subcutaneous fat with smaller fat cells compared with F-M transsexuals, with a higher baseline in vitro lipolytic activity expressed as glycerol release per milligram of triglyceride (TG) in the abdominal region (P < .05). Before cross-sex hormone treatment, no differences in lipolytic activity stimulated with arterenol (ART), isoproterenol (ISO), or ISO + insulin (INS) were observed between groups or regions. After a 1-year treatment with estrogens and antiandrogens in M-F transsexuals, subcutaneous fat areas on MRI and fat cell size were increased (P < .001) and reductions were observed in the basal lipolytic activity of gluteal and abdominal fat biopsies (P < .05). Following administration of testosterone to F-M transsexuals, subcutaneous fat and fat cell size at the gluteal and abdominal depots were decreased (P < .01) and basal lipolysis was increased significantly at the abdominal level (P < .05) but not at the gluteal level. In both M-F and F-M transsexuals, no effect of sex hormone administration was observed on stimulated lipolytic activities. In conclusion, regional sex differences in the amount of subcutaneous fat, adipocyte size, and in vitro basal lipolytic activity were demonstrated that could be largely reversed by cross-sex hormone treatment in adult subjects, providing evidence for their dependence on the sex steroid milieu.
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Affiliation(s)
- J M Elbers
- Department of Endocrinology/Andrology, Research Institute of Endocrinology, Reproduction and Metabolism, Hospital Vrije Universiteit, Amsterdam, The Netherlands
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Vernon RG, Barber MC, Travers MT. Present and future studies on lipogenesis in animals and human subjects. Proc Nutr Soc 1999; 58:541-9. [PMID: 10604185 DOI: 10.1017/s0029665199000713] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Lipogenesis occurs in all vertebrate species and has a critical role in energy balance, providing a means whereby excess energy can be stored as a fat. The metabolic pathways involved and their tissue distribution in different species, including man, are well known. The responses of lipogenesis to diet and to physiological and pathological states have been the subject of many studies. At a molecular level the major rate-controlling enzymes have been identified and their acute, and to a lesser extent chronic, control by hormones have been investigated extensively. However, there is no reason to suppose that all factors regarding lipogenesis have been identified (e.g. the recent discovery of acylation-stimulating protein). Little is known about the movement of newly-synthesized triacylglycerols in cells, either for secretion or storage. The production of leptin and tumour necrosis factor alpha by adipocytes provides a novel means of feedback control of triacylglycerol production, leptin by decreasing appetite and tumour necrosis factor alpha by inducing insulin resistance. The synthesis of these peptides appears to vary with the amount of triacylglycerol in adipocytes, but the molecular basis of this process is unknown. Elucidation of the signalling systems involved in the acute and chronic regulation of lipogenesis is also important, both with respect to some homeorhetic adaptations and also in some pathological conditions (e.g. non-insulin-dependent diabetes). Finally, molecular biology is revealing unexpected complexities, such as multiple promoters and different isoforms of enzymes (e.g. acetyl-CoA carboxylase; EC 6.4.1.2) exhibiting tissue specificity. Molecular biology, through transgenesis, also offers novel and powerful means of manipulating lipogenesis.
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