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Rizk J, Sahu R, Duteil D. An overview on androgen-mediated actions in skeletal muscle and adipose tissue. Steroids 2023; 199:109306. [PMID: 37634653 DOI: 10.1016/j.steroids.2023.109306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/18/2023] [Accepted: 08/22/2023] [Indexed: 08/29/2023]
Abstract
Androgens are a class of steroid hormones primarily associated with male sexual development and physiology, but exert pleiotropic effects in either sex. They have a crucial role in various physiological processes, including the regulation of skeletal muscle and adipose tissue homeostasis. The effects of androgens are mainly mediated through the androgen receptor (AR), a ligand-activated nuclear receptor expressed in both tissues. In skeletal muscle, androgens via AR exert a multitude of effects, ranging from increased muscle mass and strength, to the regulation of muscle fiber type composition, contraction and metabolic functions. In adipose tissue, androgens influence several processes including proliferation, fat distribution, and metabolism but they display depot-specific and organism-specific effects which differ in certain context. This review further explores the potential mechanisms underlying androgen-AR signaling in skeletal muscle and adipose tissue. Understanding the roles of androgens and their receptor in skeletal muscle and adipose tissue is essential for elucidating their contributions to physiological processes, disease conditions, and potential therapeutic interventions.
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Affiliation(s)
- Joe Rizk
- Université de Strasbourg, CNRS, Inserm, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
| | - Rajesh Sahu
- Université de Strasbourg, CNRS, Inserm, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France
| | - Delphine Duteil
- Université de Strasbourg, CNRS, Inserm, IGBMC UMR 7104- UMR-S 1258, F-67400 Illkirch, France.
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2
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Venkatesh VS, Grossmann M, Zajac JD, Davey RA. The role of the androgen receptor in the pathogenesis of obesity and its utility as a target for obesity treatments. Obes Rev 2022; 23:e13429. [PMID: 35083843 PMCID: PMC9286619 DOI: 10.1111/obr.13429] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 01/09/2022] [Accepted: 01/09/2022] [Indexed: 11/27/2022]
Abstract
Obesity is associated with hypothalamic-pituitary-testicular axis dysregulation in males. Here, we summarize recent evidence derived from clinical trials and studies in preclinical animal models regarding the role of androgen receptor (AR) signaling in the pathophysiology of males with obesity. We also discuss therapeutic strategies targeting the AR for the treatment of obesity and their limitations and provide insight into the future research necessary to advance this field.
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Affiliation(s)
- Varun S Venkatesh
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria
| | - Mathis Grossmann
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria.,Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria.,Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Rachel A Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria
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3
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Varghese M, Griffin C, Abrishami S, Eter L, Lanzetta N, Hak L, Clemente J, Agarwal D, Lerner A, Westerhoff M, Patel R, Bowers E, Islam M, Subbaiah P, Singer K. Sex hormones regulate metainflammation in diet-induced obesity in mice. J Biol Chem 2021; 297:101229. [PMID: 34599964 PMCID: PMC8526779 DOI: 10.1016/j.jbc.2021.101229] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/13/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022] Open
Abstract
Men have a statistically higher risk of metabolic and cardiovascular disease than premenopausal women, but the mechanisms mediating these differences are elusive. Chronic inflammation during obesity contributes to disease risk and is significantly more robust in males. Prior work demonstrated that compared with obese males, obese females have reduced proinflammatory adipose tissue macrophages (ATMs). Given the paucity of data on how sex hormones contribute to macrophage responses in obesity, we sought to understand the role of sex hormones in promoting obesity-induced myeloid inflammation. We used gonadectomy, estrogen receptor-deficient alpha chimeras, and androgen-insensitive mice to model sex hormone deficiency. These models were evaluated in diet-induced obesity conditions (high-fat diet [HFD]) and in vitro myeloid assays. We found that ovariectomy increased weight gain and adiposity. Ovariectomized females had increased ATMs and bone marrow myeloid colonies compared with sham-gonadectomized females. In addition, castrated males exposed to HFD had improved glucose tolerance, insulin sensitivity, and adiposity with fewer Ly6chi monocytes and bone marrow myeloid colonies compared with sham-gonadectomized males, although local adipose inflammation was enhanced. Similar findings were observed in androgen-insensitive mice; however, these mice had fewer CD11c+ ATMs, implying a developmental role for androgens in myelopoiesis and adipose inflammation. We concluded that gonadectomy results in convergence of metabolic and inflammatory responses to HFD between the sexes, and that myeloid estrogen receptor alpha contributes minimally to diet-induced inflammatory responses, whereas loss of androgen-receptor signaling improves metabolic and inflammatory outcomes. These studies demonstrate that sex hormones play a critical role in sex differences in obesity, metabolic dysfunction, and myeloid inflammation.
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Affiliation(s)
- Mita Varghese
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Cameron Griffin
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Simin Abrishami
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Leila Eter
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicholas Lanzetta
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Layla Hak
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Jeremy Clemente
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Devyani Agarwal
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Arianna Lerner
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Maria Westerhoff
- Department of Pathology, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Ravi Patel
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Emily Bowers
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Mohammed Islam
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Perla Subbaiah
- Department of Mathematics and Statistics, Oakland University, Rochester, Michigan, USA
| | - Kanakadurga Singer
- Department of Pediatrics, Michigan Medicine, University of Michigan, Ann Arbor, Michigan, USA.
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4
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Chiarella SE, Cardet JC, Prakash YS. Sex, Cells, and Asthma. Mayo Clin Proc 2021; 96:1955-1969. [PMID: 34218868 PMCID: PMC8262071 DOI: 10.1016/j.mayocp.2020.12.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/19/2020] [Accepted: 12/17/2020] [Indexed: 12/15/2022]
Abstract
There are marked sex differences in asthma prevalence and severity. Sex hormones play a central role in these sex biases and directly interact with multiple key cells involved in the pathogenesis of asthma. Here we review the known effects of estrogen, progesterone, and testosterone on airway epithelial cells, airway smooth muscle cells, the mononuclear phagocyte system, innate lymphoid cells, eosinophils, mast cells, T cells, and B cells, all in the context of asthma. Furthermore, we explore unresolved clinical questions, such as the role of sex hormones in the link between asthma and obesity.
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Affiliation(s)
- Sergio E Chiarella
- Division of Allergic Diseases, Department of Medicine, Mayo Clinic, Rochester, MN
| | - Juan Carlos Cardet
- Division of Allergy and Immunology, Department of Internal Medicine, University of South Florida, Tampa
| | - Y S Prakash
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, MN; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN.
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5
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Aromatase deficiency in hematopoietic cells improves glucose tolerance in male mice through skeletal muscle-specific effects. PLoS One 2020; 15:e0227830. [PMID: 31971970 PMCID: PMC6977739 DOI: 10.1371/journal.pone.0227830] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 12/30/2019] [Indexed: 12/14/2022] Open
Abstract
Estrogens are important for maintaining metabolic health in males. However, the key sources of local estrogen production for regulating energy metabolism have not been fully defined. Immune cells exhibit aromatase activity and are resident in metabolic tissues. To determine the relative contribution of immune cell-derived estrogens for metabolic health in males, C57BL6/J mice underwent bone marrow transplant with marrow from either wild-type (WT(WT)) or aromatase-deficient (WT(ArKO)) donors. Body weight, body composition, and glucose and insulin tolerance were assessed over 24 weeks with mice maintained on a regular chow diet. No differences were found in insulin sensitivity between groups, but WT(ArKO) mice were more glucose tolerant than WT(WT) mice 20 weeks after transplant, suggestive of enhanced glucose disposal (AUCglucose 6061±3349 in WT(WT) mice versus 3406±1367 in WT(ArKO) mice, p = 0.01). Consistent with this, skeletal muscle from WT(ArKO) mice showed higher expression of the mitochondrial genes Ppargc1a (p = 0.03) and Nrf1 (p = 0.01), as well as glucose transporter type 4 (GLUT4, Scl2a4; p = 0.02). Skeletal muscle from WT(ArKO) mice had a lower concentration of 17β-estradiol (5489±2189 pg/gm in WT(WT) mice versus 3836±2160 pg/gm in WT(ArKO) mice, p = 0.08) but higher expression of estrogen receptor-α (ERα, Esr1), raising the possibility that aromatase deficiency in immune cells led to a compensatory increase in ERα signaling. No differences between groups were found with regard to body weight, adiposity, or gene expression within adipose tissue or liver. Immune cells are a key source of local 17β-estradiol production and contribute to metabolic regulation in males, particularly within skeletal muscle. The respective intracrine and paracrine roles of immune cell-derived estrogens require further delineation, as do the pathways that regulate aromatase activity in immune cells specifically within metabolic tissues.
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Rubinow KB, Houston B, Wang S, Goodspeed L, Ogimoto K, Morton GJ, McCarty C, Braun RE, Page ST. Androgen receptor deficiency in monocytes/macrophages does not alter adiposity or glucose homeostasis in male mice. Asian J Androl 2019; 20:276-283. [PMID: 29205180 PMCID: PMC5952483 DOI: 10.4103/aja.aja_54_17] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor (AR) is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. Male mice bearing a cell-specific knockout of the AR in monocytes/macrophages (M-ARKO) were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type (WT) and M-ARKO mice (12–22 weeks of age, n = 12 per group) were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake (3.0 ± 0.5 g per day for WT mice vs 2.8 ± 0.4 g per day for M-ARKO mice) or total energy expenditure (0.6 ± 0.1 Kcal h−1 for WT mice vs 0.5 ± 0.1 Kcal h−1 for M-ARKO mice) were evident between groups during high-fat feeding. Liver weight was greater in M-ARKO than that in WT mice (1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02). Finally, M-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to WT mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.
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Affiliation(s)
- Katya B Rubinow
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Barbara Houston
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Shari Wang
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Leela Goodspeed
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Kayoko Ogimoto
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Gregory J Morton
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
| | | | | | - Stephanie T Page
- Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA
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Abstract
PURPOSE OF REVIEW As the ongoing epidemic of adult and childhood obesity grows, it puts a greater burden on individuals and the healthcare system due to increased prevalence of obesity-associated diseases. An important area that has gained much attention recently is the sex and gender difference related to obesity and associated complications. Basic science and clinical studies have now improved our understanding of obesity and have discovered adipose tissue biology to be key in metabolism. RECENT FINDINGS There is evidence related to the sex dichotomy in obesity in a variety of areas including adipocyte function, sex hormone effects, genetics, and metabolic inflammation leading to critical differences in adipose tissue biology. The sex and gender difference in adipose tissue is a factor that should be considered when studying an individuals' risk for obesity and metabolic dysfunction. This understanding is important for strategizing treatment and prevention measures.
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Affiliation(s)
- Eric Chang
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA
| | - Mita Varghese
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA
| | - Kanakadurga Singer
- Pediatric Endocrinology, University of Michigan Medical School, Medical Professional Building, D1205 1500 E. Medical Center Drive, Ann Arbor, MI, 48109-5718, USA.
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8
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Rubinow KB. An intracrine view of sex steroids, immunity, and metabolic regulation. Mol Metab 2018; 15:92-103. [PMID: 29551633 PMCID: PMC6066741 DOI: 10.1016/j.molmet.2018.03.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 02/26/2018] [Accepted: 03/01/2018] [Indexed: 12/21/2022] Open
Abstract
Background Over the past two decades, parallel recognition has grown of the importance of both sex steroids and immune activity in metabolic regulation. More recently, these discrete areas have been integrated in studies examining the metabolic effects of sex steroid immunomodulation. Implicit in these studies has been a traditional, endocrine model of sex steroid delivery from the gonads to target cells, including immune cells. Thus, research to date has focused on the metabolic effects of sex steroid receptor signaling in immune cells. This endocrine model, however, overlooks the extensive capacity of immune cells to generate and metabolize sex steroids, enabling the production of sex steroids for intracrine signaling – that is, sex steroid production for signaling within the cell of origin. Intracrine function allows highly cell-autonomous regulation of sex steroid exposure, and sex steroid secretion by immune cells could confer paracrine signaling effects in neighboring cells within metabolic tissues. In this review, immune cell intracrinology will denote sex steroid production within immune cells for either intracrine or paracrine signaling. This intracrine capacity of immune cells has been well established, and prior work has supported its importance in autoimmune disorders, trauma, and cancer. The potential relevance of immune cell intracrine function to the regulation of energy balance, body weight, body composition, and insulin sensitivity has yet to be explored. Scope of review The following review will detail findings to date regarding the steroidogenic and steroid metabolizing capacity of immune cells, the regulation of immune cell intracrine function, and the biological effects of immune-derived sex steroids, including the clinical relevance of immune cell intracrinology in fields other than metabolism. These findings will serve as the basis for a proposed model of immune cell intracrinology constituting a new frontier in metabolism research. Major conclusions The development of highly sensitive mass spectrometric methods for sex steroid measurement and quantitation of metabolic flux now allows unprecedented ability to interrogate sex steroid production, metabolism and secretion by immune cells. Immune cell intracrinology could reveal key mechanisms underlying immune cell-mediated metabolic regulation. Sex steroids exert immunomodulatory effects that may influence metabolic health. Immune cells can synthesize, modify, and metabolize sex steroids. Immune cell-derived sex steroids may play intracrine, autocrine, paracrine, and possibly even endocrine roles. Immune cell steroidogenesis is a largely unexplored area of metabolism research.
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Affiliation(s)
- Katya B Rubinow
- Diabetes Institute, Department of Medicine, University of Washington, School of Medicine, 850 Republican St., Box 358055, Seattle, WA 98109, USA.
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9
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Rubinow KB, Chao JH, Hagman D, Kratz M, Van Yserloo B, Gaikwad NW, Amory JK, Page ST. Circulating sex steroids coregulate adipose tissue immune cell populations in healthy men. Am J Physiol Endocrinol Metab 2017; 313:E528-E539. [PMID: 28698282 PMCID: PMC5792144 DOI: 10.1152/ajpendo.00075.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/06/2017] [Accepted: 07/06/2017] [Indexed: 12/11/2022]
Abstract
Male hypogonadism results in changes in body composition characterized by increases in fat mass. Resident immune cells influence energy metabolism in adipose tissue and could promote increased adiposity through paracrine effects. We hypothesized that manipulation of circulating sex steroid levels in healthy men would alter adipose tissue immune cell populations. Subjects (n = 44 men, 19-55 yr of age) received 4 wk of treatment with the gonadotropin-releasing hormone receptor antagonist acyline with daily administration of 1) placebo gel, 2) 1.25 g testosterone gel (1.62%), 3) 5 g testosterone gel, or 4) 5 g testosterone gel with an aromatase inhibitor. Subcutaneous adipose tissue biopsies were performed at baseline and end-of-treatment, and adipose tissue immune cells, gene expression, and intra-adipose estrogen levels were quantified. Change in serum total testosterone level correlated inversely with change in the number of CD3+ (β = -0.36, P = 0.04), CD4+ (β = -0.34, P = 0.04), and CD8+ (β = -0.33, P = 0.05) T cells within adipose tissue. Change in serum 17β-estradiol level correlated inversely with change in the number of adipose tissue macrophages (ATMs) (β = -0.34, P = 0.05). A negative association also was found between change in serum testosterone and change in CD11c+ ATMs (β = -0.41, P = 0.01). Overall, sex steroid deprivation was associated with increases in adipose tissue T cells and ATMs. No associations were found between changes in serum sex steroid levels and changes in adipose tissue gene expression. Circulating sex steroid levels may regulate adipose tissue immune cell populations. These exploratory findings highlight a possible novel mechanism that could contribute to increased metabolic risk in hypogonadal men.
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Affiliation(s)
- Katya B Rubinow
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington School of Medicine, Seattle, Washington;
- Diabetes Institute, Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Jing H Chao
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Derek Hagman
- The Fred Hutchinson Cancer Research Center, Seattle, Washington; and
| | - Mario Kratz
- Department of Nutrition and Department of Environmental Toxicology, University of California-Davis, Davis, California
| | - Brian Van Yserloo
- Department of Surgery, University of Washington School of Medicine, Seattle, Washington
| | - Nilesh W Gaikwad
- Department of Nutrition and Department of Environmental Toxicology, University of California-Davis, Davis, California
| | - John K Amory
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Stephanie T Page
- Center for Research in Reproduction and Contraception, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
- Diabetes Institute, Division of Metabolism, Endocrinology, and Nutrition, Department of Medicine, University of Washington School of Medicine, Seattle, Washington
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10
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The Role of Sex and Sex Hormones in Regulating Obesity-Induced Inflammation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1043:65-86. [PMID: 29224091 DOI: 10.1007/978-3-319-70178-3_5] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Metabolic and non-metabolic complications due to obesity are becoming more prevalent, yet our understanding of the mechanisms driving these is not. This is due to individual risk factor variability making it difficult to predict disease outcomes such as diabetes and insulin resistance. Gender is a critical factor in obesity outcomes with women having more adiposity but reduced metabolic complications compared to men. The role of immune system activation during obesity is an emerging field that links adiposity to metabolic syndrome. Furthermore, evidence from animal models suggests that sex differences exist in immune responses and, therefore, could be a possible mechanism leading to sex differences in metabolic disease. While there is still much to learn in the area of sex-differences research, this chapter will review the current knowledge and literature detailing the role of sex and sex hormones on adiposity and metabolically induced inflammation in obesity.
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11
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Testosterone Deficiency Induces Changes of the Transcriptomes of Visceral Adipose Tissue in Miniature Pigs Fed a High-Fat and High-Cholesterol Diet. Int J Mol Sci 2016; 17:ijms17122125. [PMID: 27999286 PMCID: PMC5187925 DOI: 10.3390/ijms17122125] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 12/08/2016] [Accepted: 12/12/2016] [Indexed: 12/14/2022] Open
Abstract
Testosterone deficiency causes fat deposition, particularly in visceral fat, and its replacement might reverse fat accumulation, however, the underlying mechanisms of such processes under diet-induced adiposity are largely unknown. To gain insights into the genome-wide role of androgen on visceral adipose tissue (VAT), RNA-Seq was used to investigate testosterone deficiency induced changes of VAT in miniature pigs fed a high-fat and high-cholesterol (HFC) diet among intact male pigs (IM), castrated male pigs (CM), and castrated male pigs with testosterone replacement (CMT) treatments. The results showed that testosterone deficiency significantly increased VAT deposition and serum leptin concentrations. Moreover, a total of 1732 differentially expressed genes (DEGs) were identified between any two groups. Compared with gene expression profiles in IM and CMT pigs, upregulated genes in CM pigs, i.e., LOC100520753 (CD68), LCN2, EMR1, S100A9, NCF1 (p47phox), and LEP, were mainly involved in inflammatory response, oxidation-reduction process, and lipid metabolic process, while downregulated genes in CM pigs, i.e., ABHD5, SPP1, and GAS6, were focused on cell differentiation and cell adhesion. Taken together, our study demonstrates that testosterone deficiency alters the expression of numerous genes involved in key biological processes of VAT accumulation under HFC diet and provides a novel genome-wide view on the role of androgen on VAT deposition under HFC diet, thus improving our understanding of the molecular mechanisms involved in VAT changes induced by testosterone deficiency.
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12
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Griffin C, Lanzetta N, Eter L, Singer K. Sexually dimorphic myeloid inflammatory and metabolic responses to diet-induced obesity. Am J Physiol Regul Integr Comp Physiol 2016; 311:R211-6. [PMID: 27252473 DOI: 10.1152/ajpregu.00136.2016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/30/2016] [Indexed: 01/09/2023]
Abstract
It is well known in clinical and animal studies that women and men have different disease risk as well as different disease physiology. Women of reproductive age are protected from metabolic and cardiovascular disease compared with postmenopausal women and men. Most murine studies are skewed toward the use of male mice to study obesity-induced metabolic dysfunction because of similar protection in female mice. We have investigated dietary obesity in a mouse model and have directly compared inflammatory responses in males and females. In this review we will summarize what is known about sex differences in diet-induced inflammation and will summarize our data on this topic. It is clear that sex differences in high-fat diet-induced inflammatory activation are due to cell intrinsic differences in hematopoietic responses to obesogenic cues, but further research is needed to understand what leads to sexually dimorphic responses.
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Affiliation(s)
- C Griffin
- Division of Pediatric Endocrinology, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
| | - N Lanzetta
- Division of Pediatric Endocrinology, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
| | - L Eter
- Division of Pediatric Endocrinology, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
| | - K Singer
- Division of Pediatric Endocrinology, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, Michigan
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