The protective effects of PHD-inhibitor GSK360A against ischemia injury and improve the function of frozen-thawed rat testicular graft

BACKGROUND: Spermatogonia is sensitive to the toxicity of chemotherapy and/or radiotherapy agents. Cryopreservation of testis tissue may offer fertility restoration for pre-pubertal male cancer survivors. OBJECTIVE: To investigate the effects of PHD-inhibitor GSK360A on the function of testis graft following cryopreservation. Besides, the underlying mechanism is explored. MATERIALS AND METHODS: Wister rats were randomly divided into three groups: fresh control group (neither freezing nor autograft), vehicle group (freezing + autograft + vehicle), and GSK360A group (freezing + autograft + GSK360A). The rate of apoptotic Leydig cells and expression of RIPK1 and caspase-8 were assessed on day 7 post-transplantation. At the 30 th day post-transplantation, the number of spermatogonia, as well as microvessel density of graft were measured. RESULTS: GSK360A statistically increased the number of spermatogonia per round tubule, redued the rate of apoptotic Leydig cells, and enhanced the microvessel density of the graft. Furthermore, diminished protein expression of RIPK1 and enhanced caspase-8 expression were found in the GSK360A group than in vehicle group. CONCLUSION: GSK360A exhibits protective effects on testicular frozen graft by increasing the number of spermatogonia and reducing the rate of apoptotic Leydig cells. Its mechanism may be related to attenuating ischaemic injury and switching cellular death mode from necroptosis to apoptosis in testis grafts.