Localization and expression analysis of sperm-specific glyceraldehyde 3-phosphate dehydrogenase in bull spermatozoa with contrasting sperm motility

• Published in: Andrology (Oxford) 2024-11
• Main Authors: Kumar, K Naresh, Veerappa, Vedamurthy G, Kumaresan, Arumugam, Lavanya, Maharajan, King, J Ebenezer Samuel, Sulochana, M, Patil, Shivanagouda, Jeyakumar, Sakthivel
• Format: Article
• Language: English
• ISSN: 2047-2919; 2047-2927; 2047-2927
• DOI: 10.1111/andr.13810

Poor sperm motility leading to male infertility has become a profound crisis to be addressed in this contemporary era. In many cases, the origin of poor sperm motility remains unexplained. Few studies reported the indispensable role of sperm-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDHS) in sperm motility, however, studies on GAPDHS are severely confined. The present study aimed to assess the localization patterns, expression levels, and enzyme activity of GAPDHS in normal and asthenozoospermic bulls and to examine their association with sperm functional parameters. The bull semen samples were classified into high-motile and low-motile groups (n = 7 per each group) based on the ejaculate rejection rate. Sperm kinetic parameters were assessed using computer-assisted sperm analysis (CASA). Sperm viability, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and intracellular calcium levels were measured through flow cytometry. Subsequently, GAPDHS localization was observed via immunocytochemistry. The expression levels and enzyme activity of GAPDHS were estimated using western blotting and a GAPDHS activity assay kit. Sperm viability, MMP, ROS, and live sperm intracellular calcium levels did not differ significantly between high and low motile groups. A significant positive correlation was found between MMP and sperm viability, whereas no significant association was found between MMP and sperm progressive motility. The GAPDHS was localized in the principal piece, head-midpiece junction, and at the acrosome region of bull sperm. GAPDHS localization intensity, expression levels, and enzyme activity were found significantly (p