Effects of Apigenin and Astragalus Polysaccharide on the Cryopreservation of Bull Semen

Abstract

The purpose of this study was to determine the effects of apigenin and astragalus polysaccharides on the cryopreservation of bovine semen. Apigenin, astragalus polysaccharides, or their combination were added to a frozen diluent of bovine semen. Afterwards, Computer Assisted Semen Analysis (CASA), membrane functionality, acrosome integrity, mitochondrial integrity, CAT, SOD, GSH-Px, MDA, and ROS detection were conducted. The results showed that adding 0.2 mmol/L AP or 0.5 mg/mL APS could improve the quality of frozen sperm. Compared to 0.2 mmol/L AP alone, the combination of 0.2 mmol/L AP and 0.3 mg/mL APS significantly increased the total motility (TM), average path distance (DAP), straight line distance (DSL), average path velocity (VAP), curvilinear velocity (VCL), wobble (WOB), and sperm CAT and SOD levels (p < 0.05), while reducing the ROS and MDA levels (p < 0.05). These results indicated that the addition of 0.2 mmol/L AP or 0.5 mg/mL APS alone has a protective effect on the freezing of bovine semen. Compared to the addition of 0.2 mmol/L AP, a combination of 0.2 mmol/L AP and 0.3 mg/mL APS could further improve the quality of frozen semen.

Keywords: apigenin; astragalus polysaccharide; bull semen; cryopreservation.

Figure 1

After fluorescent staining with FITC-PSA, live sperms were marked by green fluorescence (a) and dead sperms were marked by light green (b).

Figure 2

After double fluorescent staining with CFDA/PI, live sperms were marked by green heads (a) and dead sperms were marked by red heads (b).

Figure 3

After double fluorescent staining with Rh123/PI, live sperms were marked by green heads (a) and dead sperms were marked by red heads (b).

Figure 4

Effect of different concentrations of AP on the integrity of the plasma membrane (A), acrosome (B), and mitochondria (C) after the thawing of bovine semen. The different asterisks represent significant differences among the groups (* p < 0.05; ** p < 0.01).

Figure 5

Effect of different concentrations of APS on the integrity of the plasma membrane (A), acrosome (B), and mitochondria (C) after the thawing of bovine semen. The different asterisks represent significant differences among the groups (* p < 0.05; ** p < 0.01).

Figure 6

Effect of different concentrations of AP on the antioxidant enzyme activity in bull semen after thawing (A–C). The different asterisks represent significant differences among the groups (* p < 0.05; ** p < 0.01).

Figure 7

Effect of different concentrations of APS on the antioxidant enzyme activity in bull semen after thawing (A–C). The different asterisks represent significant differences among the groups (* p < 0.05; ** p < 0.01).

Figure 8

Effect of different concentrations of AP on the oxidation products of cattle semen after thawing (A,B). Different asterisk represents significant differences among the groups (* p < 0.05; ** p < 0.01).

Figure 9

Effect of different concentrations of APS on the oxidation products of cattle semen after thawing (A,B). The different asterisks represent significant differences among the groups (** p < 0.01).

Figure 10

Effect of the combined use of AP and APS on the plasma membrane, acrosome, and mitochondria of bovine semen (A–C). The different asterisks represent significant differences among the groups (* p < 0.05; ** p < 0.01; *** p < 0.001).

Figure 11

Effect of 0.2 mmol/L AP combined with each concentration of APS on the antioxidant enzyme activity after thawing of bovine semen (A–C). The different asterisks represent significant differences among the groups (* p < 0.05).

Figure 12

Effect of AP and APS on the oxidation products of cattle semen when used in combination (A,B). The different asterisks represent significant differences among the groups (* p < 0.05).