Endocrine Abstracts

Background: Growth hormone (GH) potently stimulates lipolysis, and after GH exposure, levels of serum free fatty acids (FFAs) increase in a distinct temporal pattern characterized by a 1-hour lag phase and a peak after 3 hours followed by a gradual return to baseline. This effect predominantly operates during fasting and promotes utilization of lipids from adipose tissue (AT) at the expense of glucose and protein. Prolonged fasting also downregulates the expression of the G0/G...

Context: Obesity is accompanied by blunted GH secretion but relatively normal serum IGF-I levels, which suggests increased GH sensitivity. This, however, remains to be tested at the level of GH signaling in human subjects.Objective: To compare the effects of an acute intravenous GH bolus in obese vs normal weight subjects on GH signaling pathways in adipose and muscle tissue, substrate metabolism and insulin sensitivity.Subjects an...

Background: Visceral adipose tissue (VAT) is less insulin sensitive and more harmful than subcutaneous adipose tissue (SAT). In adipocytes, IGF1 receptor signaling has been linked to insulin resistance, but it is unknown whether VAT and SAT also differ in production of IGFs. Therefore, we compared IGFs, IGFBP-4 and PAPP-A production in cultured fragments of VAT and SAT from obese subjects.Methods: VAT and SAT was collected perioperatively during elective...