Effect And Mechanism Of Brain-derived Neurotrophin Factor On Secretion Of Estradiol And Progesterone Of Human Granulose-luteal Cells

Ojective:It has been proved that brain-derived neurotrophin factor (BDNF) is produced by human cumulus granulose-luteal cells, BDNF initiate its biological effects by bounding to tyrosine kinase receptor B (TrkB) on the cell membrane. TrkB is proved expressed in ovary, including human cumulus granulose-luteal cells (HCGLCS) and human mural granulose-luteal cells(HMGLCS). Our aim is to study the effect of BDNF in secretion of estradiol and progesterone on human granulose-luteal cells. Then we study the effect of BDNF in expression of steroidogenic acute regulatory protein (star)mRNA, CYP-17 mRNA and arotamasemRNA in order to detecting the mechanism of the effect of BDNF.Methods:Follicular fluid, human granulose-luteal cells(HGLCS) were obtained from infertile women undergoing ovulation induction for fertilization-embryo transfer(IVF-ET)for male or tubal factors.1 HGLCS were cultured in serum-free mediumsl99 for 24 hours and treated by BDNF at 25ng/ml, 50ng/mland 1OOng/ml. RIA was used to examine the concentration of estradiol and progesterone. 2, HGLCS were treated for 4 hours by HCGat 0.2u/ml and the concentration of P4 in cultured media of HGLCS were evaluated by RIA. RT-PCR was used to examine the expression of STAR mRNA, CYP-17 mRNA and arotamase mRNA after treated by BDNF at 25 ng/ml, 50ng/mg and 100ng/ml .Result:1 BDNF significantly low-regulated the concentration of P4 in culture media of HGLCS, in a dose-dependent manner compared with controlthe level of P4 (P<0. 05) after treatment of BDNF, according to increasing the concentration of BDNF(from 25ng/ml , 50ng/ml lOOng/ml).BDNF do not change the level of E2.2, The sensitivity of HGLCS which being cultured with BDNF to HCG is decreased. The concentration of P4 is lower than the control group. There is no significant difference in the concentration of P4 among different experimental groups.3 BDNF can decrease the expression of STARmRNA according to increasing its concentration, (from 25ng/ml , 50ng/ml lOOng/ml), BDNF do not change the expression of CYP-17 mRNA and arotamasemRNA.Conclusions:1 BDNF can inhibit the synthesize of progesterone of HGLCS, playing a important role in ovary-adjustment.2 BDNF maybe reduce the synthesize of progesterone of HGLCS by inhibiting the expression of STAR mRNA.