Differential response to sustained stimulation by hCG & LH on goat ovarian granulosa cells.

Background & objectives: Chapekar established a model of ovarian tumourigenesis in mice by splenic transplantation of ovaries, resulting in sustained luteinizing hormone (LH) levels because of absence of feedback inhibition. There is increasing evidence of the differential response to LH or hCG under various experimental conditions. The effect of sustained hormonal stimulation in long term cultures is sparsely investigated. The study is aimed to determine the role of hCG and LH stress on caprine ovarian granulosa cells and their downstream signaling in short and long term cultures. Methods: To study the response of hCG and LH stress and downstream signaling, short term cultures were set up by exposing goat ovarian granulosa cells in primary cultures to hCG and LH stress (levels beyond their physiological doses) for 5 days (P0). Cells were sub-cultured at sixth day and subjected to prolonged LH/ hCG stress for two weeks in passage 1(P1) (long term cultures). Downstream cell signaling molecules were assessed. Intracellular cAMP was estimated by ELISA. For PKA and PKC, activity assays were performed. pERK protein expressions in short term cultures were assessed by Western blot and flowcytometry; in long term cultures, pERK expression was analyzed by flowcytometry. Results: Differential effects on cell proliferation were observed in long term cultures, where the untreated and hCG exposed cells showed markedly reduced cell proliferation after second week of exposure while LH treated cells continued to proliferate. Different levels of cAMP, PKA, PKC and phosphorylated ERK1/2 were observed on short term and long term LH stimulation. On sustained hormonal stimulation, cAMP levels were significantly (P<0.05) higher in hCG treated cultures as compared to controls and LH treated cultures. LH led to maximal elevation of ERK in long term cultures. Interpretation & Conclusions: As pERK1/2 promotes cellular proliferation, activation of ERK1/2 in LH treated cultures may be responsible for sustained growth. Prolonged LH treatment promoted growth and proliferation in caprine ovarian granulosa cells whereas prolonged exposure to hCG led to elevated levels of cAMP and decreased the rate of proliferation. Defining the signals and second messengers that act as survival or apoptotic mediators may help in elucidation of the mechanisms controlling proliferation or programmed cell death in granulosa cells.

Hyperinsulinemia and Other Risk Factors in Endometrial Carcinoma.

Thirty Patients of Histologically confirmed endometrial carcinoma admitted and treated over a period of three years in the department of obstetrics and Gynecology Govt Medical College Jammu, were studied to evaluate the risk factors in endometrial Carcinoma. The major risk factors in this study were hyperinsulinemia, hypertension, obesity and increasing age. Hyperinsulinemia has a potential role in growth and development of endometrial carcinoma, as insulin, in postmenopausal women with endometrial carcinoma, leads to increased stromal secretion of androstenedione which gets aromatized to form unbound oestradiol, having proliferative action on endometrium. The other risk factors noted in the study were early menarche, heavy menstrual flow, late menopause and diabetes. Since most of the risk factors are associated with hyperinsulinemia and insulin resistance, hyperinsulinemia can act as a good clinical marker in patients of endometrial carcinoma.