Hyperglycemia Decreases Dehydroepiandrosterone in Japanese Male with Impaired Glucose Tolerance and Low Insulin Response

Abstract

Recent studies indicate that experimentally induced hyperinsulinemia may reduce serum dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEA-S). Serum DHEA and DHEA-S decrease in diabetic patients, but the mechanism by which hyperglycemia decreases DHEA and DHEA-S is unknown. In this study, we investigated the effect of hyperglycemia on DHEA and DHEA-S in impaired glucose tolerance (IGT) by means of the 75g-oral glucose tolerance test (OGTT). We selected 30 male IGT patients receiving diet therapy only, whose insulinogenic Index was under 0.3. Oral glucose challenge significantly reduced DHEA (P=0.0001) and DHEA-S (P<0.05) at 60 and 120min after OGTT. Setting the value of DHEA and DHEA-S at time zero as 100%, we calculated the DHEA and DHEA-S values at 60 and 120min after OGTT as %DHEA(-S) 60min and %DHEA(-S)120min, respectively. DHEA and DHEA-S at time zero showed no correlation with BMI, HbA₁c, the sum of insulin values (∑IRI) or the area under the curve of plasma glucose (AUC). We found decreases in %DHEA 60min (r=-0.411, P<0.05), %DHEA-S 60min (r=-0.508, P<0.01) and %DHEA-S 120min (r=-0.393, P<0.05) as AUC increased, but ∑IRI showed no correlation with %DHEA(-S) 60min or %DHEA(-5)120min. We conclude that the depression of DHEA and DHEA-S after OGTT is attributable to hyperglycemia in male Japanese IGT with low insulin response.