Intra-Ovarian Injection of Bone Marrow c-Kit+ Cells Induced Ovarian Rejuvenation in Menopausal Rats

Abstract Background: Premature ovarian failure (POF) is a condition caused by ovarian insuffiency during the reproductive age that affects ~1% of women globally. Many attempts have been collected to find feasible and effective approach to reduce POF consequences in females. In this regard, cell-based therapies with certain cell types are touted as novel and hopeful therapeutic intervention in the clinical setting. Methods: To evaluate the restoration of ovarian function after intra-ovarian transplantation of bone marrow-derived c-Kit+ cells, a rat model of ovarian failure was produced. Rats were treated with 160 mg/kg/BW of 4-vinylcyclohexene dioxide (VCD) for 15 consecutive days. Using magnetic-activated cell sorting (MACS) technique, freshly isolated rat bone marrow-derived c-Kit+ and c-Kit- cells (4×105 cells/10 µL) were enriched and transplanted into the ovaries of treatment and control animals, respectively. Prior to transplantation as well as 2, 4, 6, and 8 weeks post-transplantation, randomly-selected rats were euthanized and ovarian tissues were subjected to pathohistological examinations and real-time PCR analyses.Results: Premature ovarian failure (POF) status was confirmed by the presence of pathological features and a decreased number of immature and mature follicles compared with control group (p<0.05). Histological examination revealed a substantial reduction of atretic follicles in POF rats receiving c-Kit+ cells in comparison with POF rats that did not receive these cells (p<0.05). Compared with control samples, angiogenesis-related genes, Angpt2 and KDR, showed increased and decreased expression in POF ovaries, respectively (p<0.05). c-Kit+ cells had potential to restore angiogenesis in the ovarian tissue to within normal ranges. Systemic levels of FSH did not significantly change in pre- or post-transplantation time points for any group (p>0.05). Notable reduction of collagen deposition was found in c-Kit treated rats. Transplantation of c-Kit+ cells also restored the reduced fertility rate (p<0.05).Conclusions: Our findings suggest that intra-ovarian administration of bone marrow-derived c-Kit+ cells can modulate angiogenesis signaling and pathological changes, leading to the rejuvenation of ovarian function of a rat model of premature menopause.