At this time, with advances in medical science, many cancers and chronic diseases are treatable, but one of their side effects is infertility. Some women also want to delay pregnancy for personal reasons. There has been some evidence that kisspeptin activates broad signals by binding to its receptor, suggesting that the role of kisspeptin in direct control of ovarian function includes follicle growth and steroid production. In this study, the effect of kisspeptin on improving the quality and results for human ovarian follicles was investigated. A section of ovary was removed laparoscopically from women between 20 and 35 years of age (n = 12). Pieces were divided randomly into two groups, control and treatment (with 1 μM kisspeptin). Real-time PCR was performed for GDF9, BMP15 and mTOR gene expression assessments. Western blotting was carried out to measure AKT and FOXO3a protein expression. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey’s test; means were considered significantly different at a P-value < 0.05. During treatment with the kisspeptin group, maturity genes are expressed. Therefore, kisspeptin is an effective substance to improve the quality of the human ovarian medium as it increases the maturity of follicles.

The present study was conducted to elucidate (1) the influence of kisspeptin (KP) on the in vitro development of preantral follicles (PFs) and (2) evolution of KP receptor gene (KISS1R) expression during ovarian follicular development in sheep. Kisspeptin was supplemented (0–100 µg/ml) in the culture medium of PFs for 6 days. The cumulus–oocyte complexes (COCs) from cultured PFs were subsequently matured to metaphase II (MII) for an additional 24 h. The proportions of PFs exhibiting growth, antrum formation, average increase in diameter, and maturation of oocytes to MII stage were the indicators of follicular development in vitro. The expression of the kisspeptin receptor gene at each development stages of in vivo developed (preantral, early antral, antral, large antral and COCs from Graafian follicles) and in vitro cultured PFs supplemented with KP was assessed using a real-time polymerase chain reaction. The best development in all the parameters under study was elicited with 10 µg/ml of KP. Supplementation of KP (10 µg/ml) in a medium containing other growth factors (insulin-like growth factor-I) and hormones (growth hormone, thyroxine, follicle-stimulating hormone) resulted in better PF development. The KISS1R gene was expressed in follicular cells and oocytes at all the development stages of both in vivo developed and in vitro cultured follicles. Higher KISS1R gene expression was supported by culture medium containing KP along with other hormones and growth factors. Accordingly, it is suggested that one of the mechanisms through which KP and other growth factors and hormones influence the ovarian follicular development in mammals is through the upregulation of expression of the KP receptor gene.

Kisspeptin is characterized as a neuropeptide with a pivotal function in female and male infertility, and its antioxidant properties have been demonstrated. In this study, the effects of kisspeptin on the improvement of the vitrification and thawing results of human ovarian tissues were investigated. In this work, 12 ovaries from patients who underwent hysterectomy were collected laparoscopically, and then 32 samples from each of their tissues were taken. Haematoxylin and eosin (H&E) staining was performed to check the normality of the ovarian tissue and, subsequently, the samples were allocated randomly into four groups, including: (1) fresh (control), (2) vitrification, (3) vitrified + 1 μM kisspeptin, and (4) vitrified + 10 μM kisspeptin groups. After vitrification, thawing, and tissue culture processes, H&E staining for tissue quality assessment, terminal deoxynucleotidyl transferase dUTP nick end labelling assay for apoptosis evaluation, and malondialdehyde (MDA), superoxide dismutase (SOD), and ferric reducing ability of plasma tests for oxidative stress appraisal were carried out. Our histological results showed incoherency of ovarian tissue morphology in the vitrification group compared with other groups. Other findings implicated increased apoptosis rate and MDA concentration and reduced SOD activity and total antioxidant capacity (TAC) in the vitrification group compared with the control group (P < 0.05). Moreover, decreased apoptosis rate and MDA concentration, and increased TAC and SOD function were observed in the vitrification with kisspeptin groups (1 μM and 10 μM) compared with the vitrified group (P < 0.05). Our reports express that kisspeptin is an effective agent to overcome the negative effects of vitrification by regulating reactive oxygen species-related apoptotic processes.