Regulation of human adipose tissue gene expression in relation to obesity and insulin resistance

Abstract

Obesity is associated with insulin resistance (IR) and type 2 diabetes mellitus. Among possible mechanisms leading to IR are increased plasma levels of free fatty acids and Alfred levels of adipokines secreted from adipose tissue (AT). In the first part of the work, we studied obese patients during different nutritional and physical activity interventions. Phenotypic data were related to the expression of AT genes potentially involved in the regulation of insulin sensitivity (IS) and/or low-grade inflammation. We confirmed that aerobic and dynamic strength training improved IS and demonstrated that these interventions do not promote changes in subcutaneous AT gene expression or in plasma levels of adiponectin, interleukin-6, interleukin-1 beta and tumor necrosis factor-alpha, but decrease circulating leptin level. Very low calorie diet followed by low calorie diet and weight maintenance period enhanced IS in obese women and diminished retinol-binding protein 4 (RBP4) in plasma, but RBP4 mRNA levels were reduced only after very low calorie diet. Our findings indicate that the investigated adipokines, except potentially leptin, might not be mediators of changes in IS induced by lifestyle interventions. In the second part of the work, we investigated the role of peroxisome proliferator-activated receptors...

Obezita je spojena s inzulinovou rezistencí a diabetes mellitus 2. typu. Mezi možné mechanismy vedoucí k IR jsou zvýšené plazmatické hladiny volných mastných kyselin a Alfred level adipokinů vylučujících z tukových tkání. V první části práci jsme studovali obézní pacienty s různými výživovými režimy a různými fyzickými aktivitami - zátěží. Ve druhé části práce jsme zkoumali roli PPA receptorů na sekreci proteinu v lidské podkožní tukové tkáně. Tato studie přispívá k pochopení vztahu mezi adipokiny a inzulinovou rezistencí.