Effects of vitamin D on ovary in experimental polycystic ovary syndrome: A light and electron microscobic study

Polycystic Ovary Syndrome (PCOS) is an endocrine disorder characterized by hyperandrogenism, oligo-anovulation and polycystic ovarian morphology. So far, the pathogenesis of PCOS are not fully understood and different treatment approaches are applied according to the symptoms. Recently, vitamin D treatment have been widely used for reducing the symptoms of PCOS and effects of this treatment on hormonal and metabolic abnormalities are heavily researched in clinical and experimental studies. However, there is no light and electron microscopic study in the literature which exhibits the effects of vitamin D on the ovarian tissues of patients with PCOS. In our study; we aimed to investigate the effects of vitamin D treatment on ovary tissues in a rat model of PCOS with DHEA administration using light and electron microscopy techniques. In our study, 21 days old 24 female prepubertal rats were used and divided into 3 groups each consisted of 8 animals. In group 1, 0.2 ml sesame oil + 0.01 ml 95% ethanol was injected subcutaneously and used as control group. In group 2, PCOS was created by the injection of 6 mg / kg DHEA/day subcutaneously. In group 3, PCOS was created by 6 mg / kg / day DHEA and at the same time 120ng / 100g 1,25 (OH) 2D3/ treatment was performed weekly. At the end of the 28th day, the blood samples were collected from rat under anesthesia and FSH, LH and testosterone levels were measured. The ovarian tissue were obtained for light and electron microscopic examinations and prepared according to the routine tissue preparation methods. Slides were examined by Olympus BX53 microscope for light microscopic evaluation and follicle counting. Tissue samples were analyzed with a JEOL JEM-1400 transmission electron microscope for ultrastructural evaluation. In our study; FSH, LH levels, LH / FSH ratio and testosterone levels showed a significant increase in PCOS group when compared with the control group. Moreover FSH, LH levels, LH / FSH ratio and testosterone levels were significantly lower in the treatment group than the PCOS group. In PCOS group, increased number of atretic follicles and cystic follicles were seen with light microscopic analysis. Cystic follicles with attenuated granulosa layers and thickened theca cell layers and lipid accumulation in interstitial cells were observed by electron microscope. It is observed that atretic and cystic follicles were decreased as a result of the vitamin D treatment. In conclusion; although positive effects of vitamin D is found on hormonal and structural changes, we thought that long-term use of vitamin D may be more beneficial in PCOS. In addition further studies are needed to clarify the effects of long-term vitamin D treatment and could be considered as a viable treatment option for PCOS patients with the advancing knowledge about the effects of vitamin D.