Another finding was the downregulation of testicular levels of mRNA for cytochrome P450scc
, cytochrome P450c17, 3[beta]-hydroxysteroid dehydrogenase (3[beta]-HSD), 17[beta]-hydroxysteroid dehydrogenase (17[beta]-HSD), testicular steroidogenic acute regulatory protein (StAR), androgen receptor (AR) and a decreased in vitro activity of testicular steroidogenic enzymes.
Severe combined adrenal and gonadal deficiency caused by novel mutations in the cholesterol side chain cleavage enzyme, P450scc
. J Clin Endocrinol Metab.
Under control of high pulsatile release of LH, the theca cells upregulate the expression of steroidogenic acute regulatory protein (StAR), P450 sidechain cleavage (P450scc
), 3[beta]-hydroxysteroid dehydrogenase (3[beta]-HSD), and cytochrome P450c17 (CYP17) and increase steroidogenic activity in the theca cells , thereby producing androstenedione.
The first step in the path of P4 biosynthesis is performed by the cytochrome P450 side-chain cleavage (P450scc
), which converts cholesterol into pregnenolone.
Kortner and Arukwe, (2007) reported the roles of steroidogenic acute regulatory protein (StAR) in the movement of cholesterol across the mitochondrial membrane and the final conversion to pregnenolone by cytochrome P450-mediated side-chain cleavage enzyme (P450scc
), as a strong rate-limiting step in acute steroid production.
In addition, some information about the molecular mechanism underlying the effects of VPA on the male reproductive system, especially effects on spermatogenesis and sex hormone production including testicular Ki-67, phosphorylated proteins, steroidogenic acute regulatory protein (StAR), and cholesterol side-chain cleavage enzyme (P450scc
) has been published by our group (Sukhorum et al., 2016).
All nervous cells, indeed, possess the synthetic machinery deputed to produce neurosteroids, for instance, the P450 cholesterol side-chain cleavage enzyme, P450SCC
; 17[alpha]-hydroxysteroid dehydrogenase, 17[alpha]HSD; 3[beta]-hydroxysteroid dehydrogenase, 3[beta]-HSD, as well as the enzymatic pathways converting them into neuroactive metabolites .
(2014) activity, mRNA expression level of StAR and P450scc
Shah and Khan Lipid peroxidation, hydrogen peroxide, (2014) nitrite and protein levels TABLE 2.
Zirkin, "Temporal relationships among testosterone production, steroidogenic acute regulatory protein (StAR), and P450 side-chain cleavage enzyme (P450scc
) during Leydig cell aging," Journal of Andrology, vol.
Furthermore, the activity of catalase in both rat and pig ovaries has been shown to be positively correlated with the amount of ferredoxin and cytochrome P450scc
, which are two constituents of the steroidogenic electron transport chain .
At PND30, testicular mRNA expression of steroidogenic acute regulatory protein (StAR) and of cholesterol side chain cleavage enzyme (P450scc
) was significantly decreased in [alpha]-/- males compared to [alpha]+/+ controls (Figures 3(b) and 3(c)).
Effects of a phytosterol mixture on male fish plasma lipoprotein fractions and testis P450scc