Effect of vitamin D on ovary damage caused by methotrexate

Aim: We aimed to investigate the effects of vitamin D on methotrexate induced ovarian damage histopathological, immunohistochemical, and biochemical evaluations. Material and Method: Thirty-six Wistar Albino rats were divided into four groups: control, VD, MTX and MTX+D groups. After 14-day experimental period, vaginal smear samples were obtained from the rats, and those determined to be in the proestrus phase were sacrificed for ovarian tissue collection. Histopathological HE, Masson's trichrome, toluidine mavisi, caspase-3, VDR, were performed on ovarian tissues. Follicle counts were conducted to evaluate ovarian reserve. Biochemical parameters including TOS, TAS, AMH, FSH, LH, estrogen, VD, calcium, and phosphate levels were measured using ELISA kits and spectrophotometric methods. Results: MTX group showed increased atretic follicles, connective tissue, inflammatory cell accumulation, and apoptotic bodies in granulosa cells. Mast cells increased (not statistically significant), caspase-3 immunoreactivity rose, while VDR immunoreactivity decreased. MTX+D group had no changes in follicle numbers but showed decreased caspase-3 immunoreactivity and increased VDR immunoreactivity. VD administration reduced MTX-induced TOS levels, but this decrease was not statistically significant. Serum VD levels increased. Conclusion: This study demonstrated that MTX increases oxidative stress and causes ovarian damage, but it does not result in changes in the number of primordial follicles and AMH levels. On the other hand, it led to an increase in the number of atretic follicles and apoptotic cells. Moreover, we found that the treatment of VD to the rats did not demonstrate the expected therapeutic effect when all parameters were examined. Keywords: Vitamin D, Methotrexate, Ovary