Reproduction Abstracts

Cryopreservation is the most promising approach for storing spermatozoa. However, it could lead substantial damage to spermatozoa. We present here a couple of functional tests and 2DE PAGE proteome map of bovine spermatozoa in order to evaluate the effect of each cryopreservation procedure, e.g. fresh semen, after cooling, adding cryo-protectant (CP) and thawing on spermatozoa. Our result demonstrated that the cryopreservation procedure reduced the motility (%), viability (%) and mitochondrial activity (%) of spermatozoa whereas the acrosome reaction (%) increased significantly. The differentially expressed proteins (greater than threefolds) in fresh vs cooling, fresh vs CP, fresh vs thawing, cooling vs CP, cooling vs thawing, and CP vs thawing were 7, 3, 3, 2, 6, and 2 respectively. Among the proteins differed in abundance (total 23), F-actin-capping protein subunit beta (CAPZB) and outer dense fiber protein 2 (ODF2) were linked with actin-based cytoskeleton assembly, whereas glutathione S-transferase mu 3 (GSTM3) was related with glutathione metabolism. The significantly correlated proteins with notch pathway were CAPZB, triosephosphate isomerase (TPI), pyruvate dehydrogenase E1 component subunit beta (PDHB) and ODF2. TPI, PDHB and CAPZB, ODF2 were correlated with glucose metabolism and actin cytoskeleton regulation respectively. Additionally, CAPZB and NME7 were correlated with actin cytoskeleton assembly and pyrimidine metabolism, respectively. These marked differences in proteins and their related signaling pathways suggest a logical ground of sperm functional modifications during cryo-preservation in the proteomic viewpoint. Additionally, we anticipate that these finding might apply for development of novel approaches to evaluate sperm cryo-damage. This work was supported by the ‘Cooperative Research Program for Agricultural Science and Technology Development’ (PJ008415) of RDA, Korea.