The effect of cytoprotective protein PTD-FNK on lipopolysaccharide-induced inflammatory testicular injury in mice
The objective of this study was to explore the mechanism of cytoprotective protein PTD-FNK on lipopolysaccharids-induced inflammatory testicular injury in mice.30 C57BL/6J male mice were randomly divided into blank group,LPS group(20 mg/kg),LPS+PTD-FNK group(0.1 mg/kg,0.3 mg/kg,and 0.5 mg/kg).The blank group mice were intraperitoneally injected with 0.9%normal saline,and the LPS+PTD-FNK group mice were intraperitoneally injected with normal saline containing different con-centrations of PTD-FNK for pre-protection for 1 h,and then the mice were intraperitoneally injected with 20 mg/kg LPS to induce testicular inflammation for 6 h,and then the mice were killed by cervical dislocation.Testis of mice in each group were taken for subsequent experiments.The morphological and structural changes of testicular tissue were observed after HE staining.The protein expressions of NLRP3,Caspase-1,GSDMD and IL-1β in testicular cells were detected using Western-blot,and the levels of testosterone secretion were detected using enzyme linked immunosorbent assay(ELISA).Real-time fluorescence quantitative PCR(RT-qPCR)was used to detect the mRNA expression of testosterone synthe-sis-related genes(STAR,CYP11A1,17β-HSD,and 3β-HSD),inflammatory factor related genes(IL-6,IL-1β,and TNF-α)and blood-testis barrier(BTB)related genes(CX-43,ZO-1,and Occludin)in mice.Compared with LPS group,the pathological injury of testis in LPS+PTD-FNK group was significantly improved.The mRNA expression of IL-6,TNF-α and IL-1β significantly decreased,while the mRNA expression of CYP11A1,17β-HSD,3β-HSD,CX-43,ZO-1 and Occludin significantly increased.The levels of testosterone secretion in mice were significantly increased,and the pyroptosis related proteins expressions of NLRP3,Cas-pase-1,GSDMD and IL-β were significantly decreased.In conclusion,the study indicated 0.3 mg/kg PTD-FNK could alleviate testicular inflammatory injury and reduce testicular cell pyrodeath.0.3 mg/kg PTD-FNK could enhance the function of blood-testis barrier and improve the synthesis and secretion of testosterone in mice to a certain extent.