Investigation of the relationship between kisspeptin/kiss1r protein expressions and pathological changes in human testic tissues

Objective: In our study, the expression and localization pattern of Kisspeptin/KISS1R in healthy and pathological (non-obstructive azoospermia) human testicular tissues was investigated. Method: 83 volunteer patients who applied to the Urology Department of Akdeniz University Faculty of Medicine and who met the criteria for normal and non-obstructive azoospermia (NOA) were included of the study. For the diagnosis infertility from the cases, after the pathology was defined in testicular tissue samples, the cellular localization patterns of Kisspeptin/KISS1R were evaluated immunohistochemically. FSH, LH, and testosterone hormone levels were measured from blood samples taken from control and NOA patients before TESE. Results: Expressions of Kisspeptin and KISS1R were identified in all germ cells except elongated spermatids in control human testis. Kisspeptin expression showed a nuclear staining pattern in preleptotene, pachytene and round spermatids in the control, hypospermatogenesis and maturation arrest groups. Kisspeptin expression in Sertoli cells was found to be significantly lower in the SCO group (p=<0.001). In Leydig cells, Kisspeptin was nuclear and cytoplasmic in the control and hypospermatogenesis groups, while it was only cytoplasmic in the SCO group. Interestingly, Kisspeptin was observed to mark germ cells, which is rarely seen in patients with SCO syndrome. However, KISS1R expression, which showed a significant decrease in Sertoli cells in the SCO group, was remarkable (p=<0.001). There was significant cytoplasmic and nuclear KISS1R expression in Leydig cells in the control group. Only cytoplasmic staining pattern was observed in the SCO group. Conclusion: With our study, the localization of Kisspeptin and its receptor in normal and human testicular tissues with NOA pathology was defined for the first time. Keywords: Kisspeptin, KISS1R, human testis, azoospermia, infertility