Quercetin interferes with the fluid volume and receptivity development of the uterus in rats during the peri-implantation period

•Quercetin interferes with uterine fluid volume, CFTR, ENaC and AQP expression in early pregnancy.•Quercetin alters the ultrastructure of endometrium in early pregnancy.•Quercetin alter expression of uterine receptivity markers in early pregnancy.•Quercetin affects serum sex-steroid levels in early pregnancy.•These changes cause reduced number of embryo implantation following quercetin treatment.

HypothesisQuercetin could induce changes to the fluid volume and receptivity development of the uterus during peri-implantation period.MethodsFemale rats were treated with quercetin (10, 25 and 50 mg/kg/day) subcutaneously beginning from day-1 pregnancy. Uterus was harvested at day-4 (following three days quercetin treatment) for morphological, ultra-structural, protein and mRNA expressional changes and plasma sex-steroid levels analyses. In another cohort of rats, implantation rate was determined at day-6 (following five days quercetin treatment).ResultsAdministration of 50 mg/kg/day quercetin causes increased in uterine fluid volume and CFTR expression but decreased in γ-ENaC, AQP-5, AQP-9 claudin-4, occludin, E-cadherin, integrin αnβЗ, FGF, Ihh and Msx-1expression in the uterus. Pinopodes were poorly develop, tight junctions appear less complex and implantation rate decreased. Serum estradiol levels increased but serum progesterone levels decreased.ConclusionsInterference in the fluid volume and receptivity development of the uterus during peri-implantation period by quercetin could adversely affect embryo implantation.