Objective: To investigate the expressions of the adenylate kinase (AK) family in the sperm of asthenospermia patients.
Methods: We collected semen samples from 30 asthenospermia patients and another 30 normal healthy males, detected the mRNA and protein expressions of AKs by RT-PCR and Western blot, localized the AKs by immunofluorescence assay and immunohistochemistry, and analyzed their association with sperm motility.
Results: RT-PCR and Western blot showed that AKs 1－9 were expressed in the sperm of all the subjects, and the mRNA and protein expressions of AK1, AK6 and AK7 were significantly lower in the asthenospermia patients than in the normal males. In the testis, AK1 and AK7 were expressed in the cytoplasm while AK6 in the nucleus, and in the sperm, the former two were localized in the flagella while the latter one in the sperm head. Antibody blocking experiments showed that none of the AK1, AK6 and AK7 antibodies had any significant effect on the total or progressive motility of the sperm while cultured with each alone, but co-culturing with the three antibodies markedly reduced the total sperm motility (［80.5 ± 2.4］%) and progressive sperm motility (［60.6 ± 3.6］%) in comparison with those in the control group (［87.6 ± 3.3］% and ［70.2 ± 2.3］%) (P < 0.05).
Conclusions: The mRNA and protein expressions of AK1, AK6 and AK7 are significantly down-regulated in the sperm of asthenospermia patients, which may be closely related with reduced sperm motility.
Keywords: asthenospermia; sperm; adenylate kinase.