10 µg of DNA were complexed with 1.6 µl of in vivo-jetPEI (N/P of 8) in 30 µl and microinjected into seminiferous tubules

PURPOSE: To evaluate the expression of Cold-inducible RNA-binding protein (CIRP) in torsion/detorsion of the testes in different phases and demonstrate the protective effect of CIRP on testicular injury after torsion/detorsion (T/D) in an experimental mouse model. METHODS: Twenty-four male BALB/c mice were divided randomly into 8 groups: normal control group (N), sham-operated group (S), torsion 2 h group (T2h), torsion/detorsion 12 h group (T/D12h), and T/D24h, T/D48h, T/D72h, and T/D96h groups. The testes were examined for the expression levels of CIRP. Another 32 male BALB/c mice were divided randomly in to 4 groups: normal control group (N), T/D group, T/D+pcDNA3.1 group, and T/D + pcDNA3.1-CIRP group. The plasmids were transfected into testes with in vivo-jetPEI. After 3 days, morphological changes, mean seminiferous tubule diameter (MSTD), and the number of the germ cell layers were observed. Superoxide dismutase (SOD) activity, the levels of malondialdehyde (MDA), and Bcl-2/Bax ratios were studied in the different groups. RESULTS: Compared with the N and S groups, the expression of CIRP in the T2h group was down-regulated. In T/D groups, the levels of CIRP were reduced in a time dependent manner. Compared to T/D and T/D+pcDNA3.1 group, the MSTD, number of the germ cell layers, SOD activity, and Bcl-2/Bax ratio increased in T/D + pcDNA3.1-CIRP group, while the level of MDA decreased. CONCLUSIONS: The results of our study have shown that down-regulated CIRP is involved in testicular injury after testicular torsion/detorsion. Up-regulation of the expression of CIRP may reduce the damage caused by torsion/detorsion, possibly by preventing germ cell oxidative stress and apoptosis.