Experimental data from cultured human GCs from both control and PCOS women suggest that neither PI3K nor MAPK pathway are involved in insulin induced steriodogenesis (36) which is in contrast to theca cells where PI3K has been shown to be involved (27).
Baillargeon and Nestler (39) postulated the former view as the cultured theca cells from PCOS women secrete more androgen upon insulin stimulation compared to normal cells.
The first study by Wood et al (41) on theca cells from PCOS and normal ovary showed differential expression of 346 genes.
Interactive stimulation by luteinizing hormone and insulin of the steroidogenic acute regulatory (StAR) protein and 17[alpha]lpha-hydroxylase/17, 20lyase (CYP17) genes in porcine theca cells.
Insulin augmentation of 17[alpha]-hydroxylase activity is mediated by phosphatidyl inositol 3-kinase but not extracellular signal-regulated kinase-1/2 in human ovarian theca cells.
Alterations in mitogen-activated protein kinase kinase and extracellular regulated kinase signaling in theca cells contribute to excessive androgen production in polycystic ovary syndrome.
Augmented androgen production is a stable phenotype of propagated theca cells from polycystic ovaries.
The molecular phenotype of polycystic ovary syndrome theca cells and new candidate PCOS genes defined by microarray analysis.