Study On Clomiphene Citrate Inhibits Rats Endometrial Proliferation And Its Mechanism

Objectives:Due to it is very cheap and easy to use, Clomiphene citrate (Clomiphene, Citrat e, CC) is a common clinical medicine to promoting ovulation in mini-stimulus. CC can inhi bit the proliferation of endometrial, reduce the endometrial thickness and endometrial recep tivity, resulting lower clinical pregnancy rate birth rate of tube baby. However, molecular m echanism of CC inhibiting proliferation of endometrial volume is not yet clear In order to fi nd out how CC through the inhibition of endometrial cell proliferation of endometrial recep tivity, and to improve the clinical success rate of low stimulus. The purpose of this study is to find out how CC reduce the endometrial receptivity though inhibiting endometrial cell pr oliferation and improve the protocol of mini-stimulus. The molecular mechanism of CC inh ibiting proliferation of endometrial volume was clarified preliminary by detecting the effect of estradiol (Estradiol, E2) anti estrogenic to antagonize CC. E2 was proved can ease the e ndometrial proliferative disorders, which was caused by CC in this study. This research can also provide some evidences of E2 increasing the pregnancy rate.Methods:In this study, we focused on female Sprague-Dawley rats as the object of study with 220-250g body weight, the rats were clomiphene citrate intragastric administration, then make cell smear staining with the rats’ uterus. Cycle was observed, and intragastrical administration for six days in proestrus was carried with:clomiphene citrate (Clomiphene, Citrate, CC, estradiol (Estradiol), E2),0.9%normal saline (Contral, CO), CC group, CO group with 5 rats in each group (CC:1mg per 1kg rat weight; E2:10mg per 1kg rat weight).Proteins of uterus were extracted for Western blot, related PI3K/AKT, JNK, NF-κB and mitochondrial signaling pathways, and the level changes in the mRNA transcription of estrogen receptor. CC+E2, CC, CO with 5 rats in each group, were administered for ten days. Extracting the total protein of endometrial tissue after the last administration.Proteins of uterus for Western blot, related PI3K/AKT, JNK, NF-κB and mitochondrial signaling pathway related protein again.Results:CC group growth factor in endometrial was significantly lower than the control group (P<0.05), After E2 co-administration with CC, its growth signal factor was increased than that of CC group (P<0.05), but not restored to normal level. The expression of CC JNK and NF-κB signaling pathway protein increased significantly than that in CO group, the E2 co-administration with CC, administration of JNK, NF-κB signaling pathway protein than in the CC group did not significantly change. fluorescence quantitative PCR of ESR1, ESR2, CO group did not change compare wuth CC group, that the expression of ESR1 transcript was significantly higher than that of ESR2.Conclusion:1 clomiphene citrate can reduce endometrial thickness and endometrial receptivity; 2 clomiphene citrate increased uterine JNK, NF-κB protein phosphorylation, and reduc the level of protein in PI3K single pathway; CC can promote endometrial cell apoptosis, inhibit the endometrial hyperplasia, and E2 co-administration with CC,can alleviate such symptoms. The possible molecular mechanisms of PI3K, JNK, NF-κB pathway reduce endometrial thickness and endometrial receptivity; 4 CC has anti-estrogen effect, but it does not affect the transcription of RNA expression of estrogen receptor.