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Purpose: Anti-Müllerian hormone (AMH) and forkhead box L2 (FOXL2) are two pivotal genes expressed in human granulosa cells (hGCs) where both genes share similar inhibitory functions on activation and follicular growth in order to preserve the ovarian follicle reserve. Furthermore, AMH and FOXL2 contribute to inhibit steroidogenesis, decreasing or preventing the activation of gonadotrophin-dependent aromatase CYP19A1 cytochrome P450 family 19 subfamily A member 1 (CYP19A1). The purpose of this study is to evaluate the role of AMH in regulating the expression of FOXL2., Methods: Primary cultures of hGCs were treated with increasing concentrations of recombinant human AMH (rhAMH; range 10-100 ng/ml) for 3 h. Negative controls were performed using corresponding amounts of AMH vehicle. Total RNA or proteins were purified and quantified by spectrophotometry. FOXL2 and CYP19A1 gene expression, normalized by reference gene ribosomal protein S7 (RpS7), was evaluated by RT-qPCR. Each reaction was repeated in triplicate. Statistical analysis was performed. Extracted proteins were analyzed by immunoblot using anti-FOXL2 and anti-β-actin as primary antibodies., Results: rhAMH treatments tested did not modulate the basal expression of aromatase CYP19A1 gene. rhAMH (50 ng/ml) was able to increase FOXL2 gene expression and its intracellular content., Conclusions: This study demonstrated the existence of an AMH-FOXL2 relationship in hGCs. AMH is capable of increasing both gene and protein expression of FOXL2. Because FOXL2 induces AMH transcription, these ovarian factors could be finely regulated by a positive feedback loop mechanism to preserve the ovarian follicle reserve.

Background: d-chiroinositol (DCI) is a inositolphosphoglycan (IPG) involved in several cellular functions that control the glucose metabolism. DCI functions as second messenger in the insulin signaling pathway and it is considered an insulin sensitizer since deficiency in tissue availability of DCI were shown to cause insulin resistance (IR). Polycystic ovary syndrome (PCOS) is a pathological condition that is often accompanied with insulin resistance. DCI can positively affects several aspect of PCOS etiology decreasing the total and free testosterone, lowering blood pressure, improving the glucose metabolism and increasing the ovulation frequency. The purpose of this study was to evaluate the effects of DCI and insulin combined with gonadotrophins namely follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on key steroidogenic enzymes genes regulation, cytochrome P450 family 19 subfamily A member 1 (CYP19A1) and cytochrome P450 side-chain cleavage (P450scc) in primary cultures of human granulosa cells (hGCs). We also investigated whether DCI, being an insulin-sensitizer would be able to counteract the expected stimulator activity of insulin on human granulosa cells (hGCs)., Methods: The study was conducted on primary cultures of hGCs. Gene expression was evaluated by RT-qPCR method. Statistical analysis was performed applying student t-test, as appropriate (P < 0.05) set for statistical significance., Results: DCI is able to reduce the gene expression of CYP19A1, P450scc and insulin-like growth factor 1 receptor (IGF-1R) in dose-response manner. The presence of DCI impaired the increased expression of steroidogenic enzyme genes generated by the insulin treatment in gonadotrophin-stimulated hGCs., Conclusions: Insulin acts as co-gonadotrophin increasing the expression of steroidogenic enzymes genes in gonadotrophin-stimulated granulosa cells. DCI is an insulin-sensitizer that counteracts this action by reducing the expression of the genes CYP19A1, P450scc and IGF-1R. The ability of DCI to modulate in vitro ovarian activity of insulin could in part explain its beneficial effect when used as treatment for conditions associated to insulin resistance.

Purpose: Anti Müllerian Hormone (AMH) has a negative and inhibitory role in many functions of human granulosa-lutein cells (hGCs) including notoriously the reduction of the aromatase CYP19A1 expression induced by follicle-stimulating hormone (FSH). No data have been provided on the possible role of AMH in modulating the response to luteinizing hormone (LH) (alone or combined with FSH) as well as its effect on other enzymes involved in steroidogenesis including aromatase P450scc. The aim of this study was to investigate the role of AMH as regulator of the basal and stimulated steroids production by hGCs., Methods: Primary culture of hGCs were incubated with hormones AMH, LH, and FSH, alone or in combination. The CYP19A1 and P450scc messenger RNA (mRNA) expression, normalized by housekeeping ribosomal protein S7 (RpS7) gene, was evaluated by reverse transcriptase quantitative PCR (RT-qPCR). Each reaction was repeated in triplicate. Negative controls using corresponding amount of vehicle control for each hormone treatment were performed., Result: AMH did not modulate the basal mRNA expression of both aromatase genes at any of the concentrations tested. Meanwhile, the strong mRNA induction of CYP19A1 and P450scc generated by a 24-h gonadotropin treatment (alone and combined) was suppressed by 20 ng/ml AMH added to culture medium., Conclusions: These findings contribute in clarifying the relationship between hormones regulating the early phase of steroidogenesis confirming that AMH is playing a suppressive role on CYP19A1 expression stimulated by gonadotropin in hGCs. Furthermore, a similar inhibitory effect for AMH was observed on P450scc gene expression when activated by gonadotropin treatment.

Using recombinant DNA technologies, a chimeric gene containing the coding sequences of follicle stimulating hormone (FSH) β-subunit and C-terminal peptide of the human chorionic gonadotrophin (hCG) β-subunit have been designed to generate a new gonadotrophin named corifollitropin alfa (CFA). CFA has longer elimination half-life and slower rate of absorption compared with FSH, which makes CFA a long-acting hormone employed as a substitute of the recombinant FSH (recFSH) in the controlled ovarian stimulation (COS). The purpose of this study is to compare the gene expression profiles elicited by bioequivalent doses of CFA or recFSH in primary cultures of human granulosa cells (hGCs). Gonadotrophins exert their functions by binding FSH receptors (FSHRs), activating signaling pathways that increase the cyclic adenosine monophosphate (cAMP) intracellular content. Bioequivalence has been defined as the dose/duration of gonadotrophin treatment able to promote the same amount of intracellular cAMP. hGCs were treated with different doses of either gonadotrophin and the cAMP was measured after different incubation times to establish the bioequivalence. Results obtained by comparing the bioequivalent treatments, showed that CFA is more effective than recFSH in inducing aromatase gene expression after 6 and 24 h from the initial stimulation in agreement with its long-acting characteristic. [ABSTRACT FROM AUTHOR]