The rate-limiting step in the biosynthesis of steroid hormones, known as the transfer of cholesterol from the outer to the inner mitochondrial membrane, is facilitated by StAR, the Steroidogenic Acute Regulatory protein. We have described that mitochondrial ERK1/2 phosphorylates StAR and that mitochondrial fusion, through the up-regulation of a fusion protein Mitofusin 2, is essential during st...

Although recent research has focused on the fundamental role(s) of steroids synthesized de novo in the brain on development, the mechanism by which production of these neurosteroids is regulated remains unclear. Steroid production in peripheral tissues is acutely regulated by the steroidogenic acute regulatory (StAR) protein, which mediates the rate-limiting step in steroid biosynthesis: the in...

Chronic autoimmune skin disease termed psoriasis is characterised by excessive keratinocyte multiplication, scaly plaques, severe inflammation, and erythema. T lymphocytes, leukocytes, vascular endothelium, epidermal keratinocytes also contribute in the pathogenesis of psoriasis. Increased leukocyte recruitment increased levels cytokines, growth factors, genetic factors like interleukin (IL)-1,...

Estradiol (E2) is suppressed in prepubertal females exposed maternally to lead (Pb); thus, we assessed effects of Pb on ovarian steroidogenic acute regulatory protein (StAR) as a potential mechanism for this action. Adult Fisher 344 females were dosed with 12 mg of lead acetate per ml of Pb acetate (PbAc) or sodium acetate (NaAc; control), beginning 30 days prior to breeding and continuing unti...

The adipocyte-derived hormone leptin is a central modulator of food intake, metabolism and neuroendocrine functions. It is also involved in a physiological loop linking the activity of the hypothalamo-pituitary-adrenal axis and adipose tissue. At the adrenal level, leptin has been shown to antagonize the effects of ACTH on glucocorticoid biosynthesis by decreasing the expression of various enzy...

Gonadotropins were recently demonstrated to be able to activate the MAPK cascade, but the physiological significance of this activation is still obscure. In the present work we demonstrate that highly luteinized human granulosa cells obtained from in vitro fertilization patients respond to human LH as well as to forskolin in phosphorylation of extracellular-signal regulated kinases 1 and 2 (ERK...

Although the role of arachidonic acid (AA) in angiotensin II (ANG II)- and potassium-stimulated steroid production in zona glomerulosa cells is well documented, the mechanism responsible for AA release is not fully described. In this study we evaluated the mechanism involved in the release of intramitochondrial AA and its role in the regulation of aldosterone synthesis by ANG II in glomerulosa ...