OBJECTIVES To examine baseline hormonal concentrations and the pharmacokinetic response on day 0 and day 28 of 28 days of androstenedione supplementation. METHODS Eight men (mean (SD) age 44.1 (3.0) years (range 40-48), weight 76.3 (9.4) kg, and percentage body fat 20.6 (6.7)) participated in a randomised, double blind, cross over, 2 x 28 day placebo controlled study. Subjects were tested on ...

BACKGROUND Gap-junctional intercellular communication (GJIC) is implicated in physicological processes and it is vitally important for granulosa cell (GC) differentiation and oocyte growth. We investigated the expression of connexin 43 (Cx43), a gap junctional protein, in normal and androstenedione-induced polycystic ovary (PCO), the effects of androstenedione on Cx43 expression, GJIC and proge...

Activin and inhibin are important local modulators of theca cell steroidogenesis in the ovary. Using a serum-free primary theca cell culture system, this study investigated the effects of inhibin on theca cell androgen production and expression of steroidogenic enzymes. Androstenedione secretion from theca cells cultured in media containing activin, inhibin and follistatin was assessed by RIA o...

Continuous infusions of Delta(4)-androstenedione-7-(3)H and testosterone-7-(3)H have been used to demonstrate that these androgens are converted to estrone and 17beta-estradiol, and contribute to the circulating blood levels of these estrogens in normal males and females. The conversion ratio (ratio of concentrations of radioactivity of free product steroid [chi(-PRO)] and free precursor steroi...

Mycobacterium smegmatis strain MC² 155 is an attractive model organism for the study of M. tuberculosis and other mycobacterial pathogens, as it can grow well using cholesterol as a carbon resource. However, its global transcriptomic response remains largely unrevealed. In this study, M. smegmatis MC² 155 cultivated in androstenedione, cholesterol and glycerol supplemented media were collected ...

Studies were conducted to evaluate the regulation of steroid production in dispersed cells from ovarian stromal tissue from 5- to 8-week-old-pullets (IM cells) and laying hens (MAT cells). Short-term incubation of IM and MAT cells with ovine (o) LH resulted in a dose-dependent increase in progesterone, androstenedione and oestradiol production; progesterone production was greater in MAT cells t...

This study explores the potential relationship between a series of cognitive abilities and testosterone, dehydroepiandrosterone (DHEA), androstenedione, and body mass index (BMI) measurements in 5-year-old children. 60 boys and 69 girls were administered a test (K-BIT) which provided measurements of fluid intelligence (Matrices subtest), crystallized intelligence (Vocabulary subtest), and IQ co...

In a recent study, we demonstrated that androstenedione was mainly converted to testosterone (T) and 5alpha-dihydrotestosterone (DHT) by digestive gland/gonad complex microsomal fractions isolated from male Marisa cornuarietis, whereas it was primarily metabolized to 5alpha-dihydroandrostenedione (DHA) by females. In the present work, the sexual dimorphic metabolism of androstenedione was furth...

A total of 53 tumors have been examined for estrogen synthesis from androstenedione and assayed for estradiol receptors. It was found that of the 40 tumors that metabolized androstenedione to estrogens, 17 tumors were estradiol receptor negative and 23 tumors were estradiol receptor positive. Of the 13 tumors that did not synthesize estrogens, 7 tumors were receptor negative and 6 tumors were r...

Androgens have an important role in ovarian follicular growth and function, but circulating androgen concentrations are also associated with ovarian dysfunction, cardiovascular disease, and metabolic disorders in women. The extent and causes of the variation in androgen production in individuals, however, are unknown. Because thecal cells of follicles synthesize androstenedione and testosterone...