Down-regulation of β-catenin in endometrium of women stimulated with clomiphene citrate compared with letrozole and natural cycles

Background: Clomiphene citrate (CC) is widely used as the first-line drug for ovulation induction. Because of peripheral anti-estrogenic action, alternatively, letrozole can be used to induce ovulation. The objective of this study was to compare the expression of the key molecule, β- Catenin, in Wnt signaling pathway involved in the proliferation of endometrium. Methods: A total of 30 women diagnosed with male factor were included in the study and randomly divided into the groups stimulated with CC (100 mg) or letrozole (5 mg), starting on day 3 of the menses for 5 days as well as women who didn’t given any treatments. On day 12 of the menstrual cycle, the evaluation of endometrialthickness (ET) using transvaginal ultrasonography and the circulating hormones of estrogen, progesterone, FSH, LH were done. The endometrial samples were taken from using Pipelle suction curette. Using Real-Time PCR and western blot, the mRNA and the protein expression of β-catenin, and GSK3β were measured in tissue samples.Results: significantly, the ET was reduced in CCtreated cycles in comparison with letrozole. The women stimulated with CC showed the mean serum level of estrogen and progesterone concentration were higher and lower, respectively, compared to letrozole. The expression of active β- catenin, and inactive GSK3β were significantly decreased at level of protein in CC compared to letrozole group without a significant difference in the mRNA expression. Conclusion: these results showed that CC adversely influenced the expression of keys molecules in Wnt signaling pathway during proliferative phase, resulting in inadequate endometrial development.

کلیدواژه ها:

Clomiphene Citrate ، Letrozole ، Endometrium ، GSK3β ، β-catenin ، Wnt signaling