Fig. 5

The effect of E2 and RA treatment on vaginal epithelial cell apoptosis and Ctnnb1 mRNA levels in WT females. (A) The strategy of RA and E2 treatment in WT ovariectomized females. After ovariectomy (OVX), the females at 14 dpp received daily subcutaneous injections (s.c.) of E2 (0.1 µg/kg body weight. OVX-E2 group), RA (2.5 mg/kg body weight. OVX-RA group) or vehicle oil (OVX-oil group) until 17 dpp, and the females were sacrificed for experiments on vaginal tissue 24 h later. (B) The mRNA levels of Raldh2, Raldh3, Rarα, Rarγ, Rxrα, Rxrβ, Ctnnb1, Bak, Bax, and Bcl2 in the vaginas of OVX-E2 and OVX-oil groups, and the mRNA levels of Ctnnb1, Bak, Bax, and Bcl2 in the vaginas of OVX-RA and OVX-oil groups. The mRNA values of OVX-oil groups were set as 1, and those of other gens were normalized accordingly. (n = 3 independent experiments). Data are presented as mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001 vs. the OVX-oil group. (C, D, E) The protein levels of RARα, RARγ, β-catenin, active β-catenin, BAK, BAX and BCL2 in the vaginas of OVX-E2 and OVX-oil groups, and the protein levels of β-catenin, active β-catenin, BAK, BAX and BCL2 in the vaginas of OVX-RA and OVX-oil groups. GAPDH was used as a loading control. (n = 3 independent experiments). Data are presented as mean ± SEM. *P < 0.05, **P < 0.01 vs. the OVX-oil group. (F) The proposed model for RA-RAR signaling in vaginal opening