[Yam polysaccharide improves sperm viability and protects sperm DNA integrity in vitro].

ABSTRACT

OBJECTIVE: To clarify the roles of yam polysaccharide (YPS) in improving sperm viability and protecting sperm DNA integrity in vitro and provide a new approach to the treatment of oligoasthenozoospermia. METHODS: We collected samples by masturbation from 36 normal fertile males aged 27－39 years. Each sample was divided into six groups blank control or treated with normal saline, vitamin C solution, and YPS solution at low (0.25 mg/ml), medium (1.0 mg/ml) or high concentration (5.0 mg/ml). Using eosin-Y staining, sperm hypotonic swelling (HOS) and sperm chromatin diffusion (SCD) test, we observed the effects of different concentrations of YPS on sperm viability, membrane integrity and nuclear DNA. RESULTS: After 24 and 48 hours of treatment, sperm viability was markedly reduced in the vitamin C (ï¼»28.5 ± 3.1ï¼½ and ï¼»6.5 ± 1.2ï¼½%), low-YPS (ï¼»31.3 ± 3.5ï¼½ and ï¼»6.5 ± 2.2ï¼½%), medium-YPS (ï¼»37.1 ± 3.5ï¼½ and ï¼»9.5 ± 2.8ï¼½%) and high-YPS groups (ï¼»38.3 ± 3.3ï¼½ and ï¼»9.0 ± 3.2ï¼½%) as compared with the blank control (ï¼»17.3 ± 2.1ï¼½ and ï¼»3.2 ± 1.3ï¼½%) (P <0.01) and normal saline groups (ï¼»13.4 ± 4.1ï¼½ and ï¼»3.1 ± 2.0ï¼½%) (P <0.01), and it was significantly higher in the medium- and high-YPS than in the vitamin C group (P <0.05 and P <0.01). The rate of sperm DNA fragmentation was remarkably decreased at 48 hours in the vitamin C (ï¼»30.5 ± 3.1ï¼½%), low-YPS (ï¼»29.4 ± 2.6ï¼½%), medium-YPS (ï¼»28.5 ± 2.3ï¼½%) and high-YPS groups (ï¼»27.9 ± 1.9ï¼½%) in comparison with the blank control (ï¼»41.7 ± 2.2ï¼½%) (P <0.01) and normal saline groups (ï¼»42.1 ± 3.3ï¼½%), markedly lower in the medium- and high-YPS than in the blank control, normal saline and vitamin C groups (P <0.05 or P <0.01), but with no statistically significant difference between the low-YPS and vitamin C groups (P >0.05). CONCLUSIONS: Yam polysaccharide can improve sperm viability and protect sperm DNA integrity in vitro.