Protective effect of <i>Angelica sinensis</i> polysaccharide (ASP) on cryopreservation-induced damage to semen of Chongming white goats

BACKGROUND: Cryopreservation of goat sperm is important for goat breeding and population expansion. However, goat spermatozoa are generally less resistant to freezing and the fertilization rate of spermatozoa is lower than that of fresh semen. OBJECTIVE: To investigate the effect of different concentrations of Angelica sinensis Polysaccharide (ASP; 0, 150, 300, 600, and 1200 μg/mL) on post-thaw quality, motility characteristics, and oxidative markers of Chongming white goat sperm. MATERIALS AND METHODS: Fresh semen from Chongming white goat (n=8; mean age, 3‐5 years of age) was collected, evaluated, and divided into five treatment groups corresponding to different ASP concentrations. Post-thaw sperm motility kinematics, plasma and acrosomal membrane integrity, and mitochondrial activity were evaluated. Additionally, this study evaluated markers of antioxidant defense, including malondialdehyde (MDA), reactive oxygen species (ROS), superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px), nitric oxide (NO) content, total antioxidant capacity (T‐AOC), as well as 5‐methylcytosine (5‐MC) level. RESULTS: The addition of 600 μg/mL ASP enhanced sperm viability and sperm kinematic parameters, improved integrities of acrosome and plasma membrane, and increased mitochondrial activity as compared with the control. Regarding oxidative markers, ASP‐added groups had reduced ROS, MDA, and NO levels in semen compared to controls. The ASP 600 μg/mL group had the lowest levels of oxidative markers, and adding 600 μg/mL ASP significantly increased SOD, catalase (CAT), and GSH-Px activities in semen. There were significant increases in T‐AOC levels in all ASP‐added groups versus the control group. Additionally, the 300 and 600 g/mL ASP‐groups showed significantly lower levels of DNA methylation 5‐MC than the control groups. CONCLUSION: Adding 600 μg/mL ASP to the Chongming white goat low-temperature diluent improves the motility characteristics and antioxidant markers of Chongming white goat semen.