Identification of asthenozoospermia-associated proteins in human seminal plasma by shotgun proteomic strategy

OBJECTIVE: To identify asthenozoospermia-associated proteins in seminal plasma by the shotgun proteomic strategy. METHODS: Six seminal plasma samples were collected by Percoll respectively from healthy fertile and asthenozoospermia volunteers, balanced, mixed, and then the mixture was separated by SDS-PAGE. The proteins in the gel were enzymolyzed, extracted and identified by the shotgun proteomic strategy. The identified proteins with the unique peptide count > or =2 or the unique peptide count=1 but the total count > or =4 were compared between the two groups. RESULTS: A total of 172 differential proteins were identified, of which, 89 were exclusively from the asthenozoospermia and 83 exclusively from the healthy fertile men. According to the molecular function, these differential proteins were mainly the types of signal transduction and catalytic activity. CONCLUSION: Functionally, 10 of the proteins are particularly important, which include annexin VI isoform 2, isoform 1 of interleukin-6 receptor subunit beta precursor, Mr 400,000 protein, cytosolic dynein heavy chain, alpha-actinin-4, receptor-type tyrosine-protein phosphatase eta precursor, vitamin D-binding protein precursor, protein S100-A11, protein S100-A9 and ANXA4.