Taxifolin: A flavonoid in the freezing medium augments post-thaw semen quality and in vivo fertility potential of buffalo bull spermatozoa

Abstract

This comprehensive study was carried out to investigate the effects of taxifolin in the freezing medium on post-thaw semen quality, and fertility potential of buffalo bull spermatozoa. Taxifolin was also evaluated for radical scavenging activity through DPPH (2, 2-diphenyl-1-picrylhydrazyl), and Nitric oxide (NO) inhibition (%) during in vitro conditions. Collected semen samples from four buffalo bulls were initially evaluated (consistency, volume, motility, and concentrations); the accepted samples were pooled, and diluted in extenders containing different doses of taxifolin (0 μM [control], 2 μM, 5 μM, 10 μM, and 20 μM). Diluted semen was gradually cooled (2 h, 4 °C), equilibrated (4 h, 4 °C), and then frozen in liquid nitrogen (−196 °C). Data analysis revealed that taxifolin supplementation (10 μM) displayed the highest DPPH-scavenging ability, and NO inhibition compared to the control (% DPPH, 67.31 vs. 13.50; and % NO, 78.25 vs. 21.25) respectively. Moreover, taxifolin supplementation (10 μM) significantly (P < 0.05) improved progressive motility (%), average path velocity (μm/sec), straight-line velocity (μm/sec), and seminal plasma glutathione peroxidase (μM), and superoxide dismutase (U/mL) of buffalo bull spermatozoa than control. Sperm plasma membrane integrity, mitochondrial transmembrane potential, acrosome integrity (%) and seminal plasma adenosine triphosphate (nmol/million), and total antioxidant capacity (μM/L) were enhanced significantly with taxifolin (10 and 20 μM) supplementing group. Lastly, taxifolin supplementation significantly improved the fertility rate (%, 69.09 vs. 40.38) compared to the control. Further studies to assess mechanisms by which taxifolin improves semen quality and fertility of buffalo spermatozoa are warranted.