Adipose tissue IL-8 is increased in normal weight women after menopause and reduced after gastric bypass surgery in obese women.
ABSTRACT Objective The menopausal transition is characterized by increased body fat accumulation, including redistribution from peripheral to central fat depots. This distribution is associated with an increased risk of type 2 diabetes and cardiovascular disease that are linked to low-grade inflammation. We determined whether postmenopausal women have higher levels of inflammatory markers, compared with premenopausal women. We also wanted to determine whether these markers are reduced by stable weight loss in obese women. Design and methods Anthropometric data, blood samples and subcutaneous adipose tissue biopsies were collected from normal weight premenopausal and postmenopausal women and obese women before and 2 years after gastric bypass (GBP) surgery. Serum protein levels and adipose tissue gene expression of inflammatory markers were investigated. Results IL-8 expression in adipose tissue and circulating levels were higher in postmenopausal vs premenopausal women. IL-8 expression was associated with waist circumference, independent of menopausal status. IL-6 expression and serum levels of monocyte chemoattractant protein (MCP)-1 were higher in postmenopausal vs premenopausal women. Two years after GBP surgery, adipose expression of IL-8, tumour necrosis factor-α and MCP-1 decreased significantly. Serum insulin levels were associated with inflammation-related gene expression before GBP surgery, but these associations disappeared after surgery. Conclusion Postmenopausal women have an increased inflammatory response in the subcutaneous fat and circulation. Inflammatory markers in adipose tissue decreased significantly after surgery-induced weight loss. This effect may be beneficial for metabolic control and reduced cardiovascular risk after weight loss.
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ABSTRACT: Much has been made of obesity's health impact, largely founded on data regarding patient weight and circulating adipose-derived mediator levels. Paradoxically, a "healthy obese" state exists, but substantial knowledge gaps also exist regarding human adipose-phenotype determinants. Surgical major amputation (AMP) patients are the "sickest-of-the-sick." Conversely, elective knee replacement (TKR) is reserved for patients who expect continued health and longevity. To delineate human adipose biology variability and clinical determinants, we studied fresh subcutaneous adipose from AMP patients, using TKR patients as controls. We hypothesized that AMP patients would display a pro-inflammatory adipokine signature, and that certain clinical conditions (diabetes, hypertension, hyperlipidemia, high BMI, uremia) would independently drive elevated adipose inflammation. AMP (n = 29) and TKR (n = 20) adipose tissue samples and clinical data were collected prospectively, and protein was isolated and analyzed for 8 adipose-related mediators. Statistical analyses included Wilcoxon's rank sum test, Fisher's exact test, and multiple linear regression modeling of clinical parameter predictors of mediator expression. Interleukin-(IL)-6, IL-8, leptin, resistin, and PAI-1 were differentially expressed (up to 200-fold) between AMP/TKR cohorts. Key clinical parameters that associated with protein levels of adipose phenotype included age, gender, hypertension, hyperlipidemia, congestive heart failure, cerebrovascular disease, renal disease, and warfarin, statin, and insulin use. BMI failed to be predictive. AMP patients display adiposopathy with a pro-inflammatory adipose phenotypic signature compared with TKR controls. BMI fails to predict phenotype, yet other clinical conditions, such as age, hyperlipidemia, and renal insufficiency, do drive adipokine expression. Understanding human adipose phenotypic determinants stands as a fundamental priority when future studies dissect the interplay between adipose biology and surgical diseases/outcomes.Annals of Vascular Surgery 04/2013; 27(3):346-52. · 0.99 Impact Factor