Identification of proteomic differences in oligozoospermic sperm sample

Objectives: Oligozoospermia is one of the most common findings present in subfertile males, but its aetiology remains unknown in most cases. In this work we have used current proteomic tools to identify, the different proteins present in oligozoospermic semen samples and therefore potentially involved in infertility. Methods: We compared the expression of 75 sperm protein spots in 3 pools of 5 oligozoospermic samples to that of 5 semen donor controls using two-dimensional proteomic analysis. Results: A total of 14 protein spots have been identified with a > 2 fold different amount in the oligozoospermic samples as compared to controls. Proteins detected as increased are, creatine kinase B (CKB), histidine triad nucleotide-binding protein 1 (HINT1), succinyl CoA 3 ketoacid coenzyme A transferase 1 precursor (OXCT1), transgelin-2 (TAGLN2), 2 spots corresponding to cytoskeletal actin (ACTB), glutathione S-transferase Mu 3 (GSTM3), annexin AS (ANXA5), cyclin dependent kinase 5 (CDK5), and proteins detected as decreased are ATP synthase beta chain, mitochondrial precursor (ATP5B), outer dense fibre protein 2 (ODF2), tubulin beta subunit (TUBB2), capping protein (actin filament) muscle Z-line, beta (CAPZB), triosephosphate isomerase 1 (PTI1). Discussion: We have identified several proteins present in different amounts in oligozoospermic sperm samples as compared to control samples. These proteins could be now be further considered as candidates for the development of diagnostic markers and open up the opportunity to gain further insight into the pathogenic mechanisms involved in oligozoospermia.