Cholesterol sulphate affects production of steroid hormones by reducing steroidogenic acute regulatory protein level in adrenocortical cells

Abstract

Steroidogenic acute regulatory (StAR) protein plays a crucial role in the intramitochondrial movement of cholesterol, where P450 side chain cleavage enzyme resides. Cholesterol sulphate (CS), which is present ubiquitously in mammalian tissues, is not only a precursor of sulphated adrenal steroids but also an inhibitor of cholesterol biosynthesis. This study was designed to examine the biological roles of CS in steroidogenesis in adrenocortical cells. Human adrenocortical carcinoma H295R cells were cultured with various amounts of CS. To evaluate steroid hormone synthesis, pregnenolone production in cells was assayed. The amount of pregnenolone produced by H295R cells in culture medium, to which over 50 mg/ml CS was added, was significantly (P!0 . 05) decreased compared with that produced by control cells. Western blot analysis was performed to determine StAR protein level using whole cell extracts from cells. StAR protein level decreased when the concentration of CS in the medium was 50 mg/ml, whereas the level of glyceraldehyde-3-phosphate dehydrogenase did not change. To examine the mechanism by which StAR gene expression is controlled, we performed RT-PCR and measured promoter activity in cells transfected with pGL 2 StAR reporter constructs. StAR mRNA level and promoter activity were decreased in cells. The decrease in StAR protein level is a result of the low StAR gene expression level. In conclusion, CS affects the production of steroid hormones by reducing StAR protein level in adrenocortical cells.

Transcriptional Regulation of Steroidogenic Genes: STARD1, CYP11A1 and HSD3B

“…Other cytokines, transforming growth factor b1 (TGFb1) and interleukin-10 (IL-10), and the adipokine leptin inhibit while leukemia inhibitory factor (LIF) increases STARD1 mRNA accumulation in adrenocortical cells in keeping with their modifications of adrenal steroidogenesis (28,(42)(43)(44)(45). Cholesterol sulfate, known to interfere with the conversion of cholesterol to pregnenolone (46), reduces basal and cAMP-stimulated STARD1 mRNA and promoter activity in H295R cells (47) whereas lipoproteins stimulate STARD1 in mouse Y1 adrenocortical tumor cells (48,49).…”

Expression of retinoic acid-related orphan receptor alpha and its responsive genes in human endometrium regulated by cholesterol sulfate

“…CS is a major sterol sulfate in human plasma that is detectable in the endometrial cells of the uterus, lungs, skin, hair, adrenal glands, and nails. CS plays a role in cellular membrane stabilization, regulation of the skin barrier, and steroid genesis [5][6][7]. Recently, we reported the inhibitory effect of proteases on CS in human endometrium [8,9].…”

Inhibition of cell invasion and protease activity by cholesterol sulfate

“…Cholesterol sulfate plays an important role in cellular membrane stabilization and skin barrier regulation (4). In the field of reproductive biology, it was reported that CS inhibited acrosin, a protease found in the sperm acrosome (5,6), and that it also regulated steroid hormone synthesis (7,8). Cholesterol sulfate plays certain roles in cell signaling pathways such as activation of protein kinases (9), and it may function as a ligand for retinoic acid-related orphan receptor a (10,11).…”