Fig. 1: CTX-induced DNA damage and apoptosis in the GCs of growing follicles.

A Western blot results of γH2AX, cPARP, PARP, and BCL-2 levels of the ovaries from mice treated with or without CTX. GAPDH and β-tubulin were blotted as loading controls. N = 6 mice per time point for each group. B Hematoxylin and eosin (H&E) staining of ovary sections 24 h after i.p. injection of PBS or CTX. Scale bar, 250 μm. C Immunofluorescence staining of ovaries collected at 6 and 24 h after the i.p. injection of PBS or CTX. TUNEL was probed with Alexa Fluor 488 (green). Rabbit monoclonal antibodies CC3 and γH2AX were detected using anti-rabbit IgG (red and yellow, respectively). Cell nuclei were labeled with DAPI (blue). Scale bar, 100 μm; N = 6 ovaries from different mice per time point for each group. D Quantitative plots for TUNEL, CC3, and γH2AX-positive follicles/total follicles. E The number of oocytes collected from the oviducts of the mice with or without CTX treatment after hCG injection. N = 8 mice for each group. F PB1 emission rates of oocytes collected from the oviducts of mice in vivo 16 h after ovulation induction. The number of analyzed oocytes is indicated (n). G Immunofluorescent staining for α-tubulin (green), phalloidin (blue), and DNA (red) of the oocytes collected from the oviducts of mice in vivo 16 h after ovulation induction. Scale bar, 20 μm. Data are the mean ± SD of at least three independent experiments. Statistical analyses were carried out using a two-tailed Student’s t-test; n.s. non-significant; **P < 0.01; and ***P < 0.001.