The short-term effect of dietary pectin on plasma levels and renal excretion of dehydroepiandrosterone sulfate.

Abstract

Studies specifically investigating the effects of single dietary components on plasma levels of dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) are rare. Especially no data is available with regard to specific dietary fibers. Therefore, the impact of pectin (a representative fiber that affects the enterohepatic recirculation of bile acids) was studied in a randomized crossover trial consisting of three diet periods characterized by the same food supply and daily doses of 0 g, 15 g or 30 g pectin. Blood and 24-h-urine samples were collected at the end of each 4-day diet period from 6 healthy male volunteers. Plasma levels of DHEA, cortisol and the major binding protein of DHEAS albumin remained unchanged with the varying pectin supplements. Also, no changes were observed for several urinary analytes including urinary DHEAS. However, effects of pectin intake (30, 15 versus 0 g/d) were seen for plasma DHEAS (9.3 +/- 2.8, 9.2 +/- 2.6, 8.0 +/- 3.1 mumol/L, p < 0.01) and total plasma cholesterol (4.4 +/- 0.7, 4.5 +/- 0.7, 4.7 +/- 0.8 mmol/L, p = 0.1). Obviously, the altered intake of fiber in the form of pectin affects plasma concentrations of DHEAS and cholesterol in an opposite direction. The reason for this is not known but a dietetically induced modulation of the binding properties of plasma albumin for DHEAS appears possible. Our findings suggest that the target tissue-available, not protein-bound fraction of circulating DHEAS (as reflected by the renal DHEAS output) is not necessarily altered when total plasma concentrations of DHEAS vary.