Microcystins and Microcystis aeruginosa PCC7806 extracts modulate steroidogenesis differentially in the human H295R adrenal model.

The aim of this study was to investigate the potential interference of cyanobacterial metabolites, in particular microcystins (MCs), with steroid hormone biosynthesis. Steroid hormones control many fundamental processes in an organism, thus alteration of their tissue concentrations may affect normal homeostasis. We used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the modulation of 14 hormones involved in the adrenal steroid biosynthesis pathway using forskolin-treated H295R cells, following exposure with either microcystin-LR (MC-LR) alone, a mixture made up of MC-LR together with eight other MCs and nodularin-R (NOD-R), or extracts from the MC-LR-producing Microcystis aeruginosa PCC7806 strain or its MC-deficient mutant PCC7806mcyB-. Production of 17-hydroxypregnenolone and dehydroepiandrosterone (DHEA) was increased in the presence of MC-LR in a dose-dependent manner, indicating an inhibitory effect on 3ß-hydroxysteroid dehydrogenase (3ß-HSD). This effect was not observed following exposure with a MCs/NOD-R mixture, and thus the effect of MC-LR on 3ß-HSD appears to be stronger than for other congeners. Exposure to extracts from both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- had an opposite effect on 3ß-HSD, i.e. concentrations of pregnenolone, 17-hydroxypregnenolone and DHEA were significantly decreased, showing that there are other cyanobacterial metabolites that outcompete the effect of MC-LR, and possibly result instead in net-induction. Another finding was a possible concentration-dependent inhibition of CYP21A2 or CYP11ß1, which catalyse oxidation reactions leading to cortisol and cortisone, by MC-LR and the MCs/NOD-R mixture. However, both M. aeruginosa PCC7806 and M. aeruginosa PCC7806mcyB- extracts had an opposite effect resulting in a substantial increase in cortisol levels. Our results suggest that MCs can modulate steroidogenesis, but the net effect of the M. aeruginosa metabolome on steroidogenesis is different from that of pure MC-LR and independent of MC production.

Resveratrol inhibits androgen production of human adrenocortical H295R cells by lowering CYP17 and CYP21 expression and activities.

Resveratrol, a natural compound found in grapes, became very popular for its suggested protective effects against aging. It was reported to have similar positive effects on the human metabolism as caloric restriction. Recently, positive effects of resveratrol on steroid biosynthesis in cell systems and in humans suffering from polycystic ovary syndrome have also been reported, but the exact mechanism of this action remains unknown. Sirtuins seem targeted by resveratrol to mediate its action on energy homeostasis. In this study, we investigated the mechanisms of action of resveratrol on steroidogenesis in human adrenal H295R cells. Resveratrol was found to inhibit protein expression and enzyme activities of CYP17 and CYP21. It did not alter CYP17 and CYP21 mRNA expression, nor protein degradation. Only SIRT3 mRNA expression was found to be altered by resveratrol, but SIRT1, 3 and 5 overexpression did not result in a change in the steroid profile of H295R cells, indicating that resveratrol may not engage sirtuins to modulate steroid production. Previous studies showed that starvation leads to a hyperandrogenic steroid profile in H295R cells through inhibition of PKB/Akt signaling, and that resveratrol inhibits steroidogenesis of rat ovarian theca cells via the PKB/Akt pathway. Therefore, the effect of resveratrol on PKB/Akt signaling was tested in H295R cells and was found to be decreased under starvation growth conditions, but not under normal growth conditions. Overall, these properties of action together with recent clinical findings make resveratrol a candidate for the treatment of hyperandrogenic disorders such as PCOS.

Resveratrol inhibits steroidogenesis in human fetal adrenocortical cells at the end of first trimester.

SCOPE: Resveratrol has a diverse array of healthful effects on metabolic parameters in different experimental paradigms but has also potential to inhibit steroidogenesis in rodent adrenals. The aim of the present study was to characterize the effects of resveratrol on human fetal adrenal steroidogenesis at gestational weeks (GW) 9-12. METHODS AND RESULTS: Adrenals from aborted fetuses (GW10-12) were used to prepare primary cultures of human fetal adrenocortical cells (HFAC). HFAC were treated in the presence or absence of ACTH (10 ng/mL) with or without resveratrol (10 µM) for 24 h. The production of steroids by HFAC was analyzed by gas and liquid chromatography coupled to tandem/mass spectrometry. The expression of steroidogenic enzymes at GW 9-12 was quantified by automated Western blotting. We observed that resveratrol significantly suppressed synthesis of dehydroepiandrosterone (DHEA), androstenedione and 11-deoxicortisol by ACTH-activated and unstimulated HFAC, which was associated with inhibition of the activities and expression of cytochromes 17α-hydroxylase/17,20 lyase (CYP17) and 21-hydroxylase (CYP21) in these fetal adrenocortical cells. CONCLUSION: Our in vitro findings on the sensitivity of human fetal adrenal steroidogenesis to resveratrol at GW9-12 suggest that intake of this polyphenol at high doses by women who are at early stages of pregnancy is undesirable.