Rutin protects boar sperm from cryodamage via enhancing the antioxidative defense

This study was aimed to investigate whether and how Rutin protects boar sperm against cryoinjury during cryopreservation. Five concentrations of Rutin with 0.2, 0.4, 0.6, 1.0, and 2.0 mM were added to the freezing extender of boar sperm, respectively, and the effects on quality and function of boar sperm after freezing-thawing were assessed. The results showed that the sperm motility, mitochondrial activity, plasma membrane integrity, and acrosomal integrity were significantly improved in 0.4 mM and 0.6 mM Rutin groups (p < .05). Compared with ganoderma lucidum polysaccharide (GLP) or Tanshinone IIA, Rutin exhibited higher rates of mitochondrial activity and acrosome integrity (p < .05). Mechanistically, the addition of Rutin at the concentration of 0.6, 0.8, and 1.0 mM significantly attenuated ROS accumulation and MDA production by improving antioxidant enzymatic activity, including SOD, CAT, and GSH-Px (p < .05). Functionally, a higher penetration rate and the increased total efficiency of fertilization were observed in the 0.4, 0.6, and 1.0 mM Rutin groups than in the control group (p < .05). Moreover, the addition of Rutin (0.6 mM) significantly induced an increase in both the cleavage and blastocyst rates (p < .05). In summary, supplementation with Rutin in cryopreservation medium protects boar sperm against ROS attack by enhancing the antioxidative defense.