Abstract
Polysaccharides were extracted from astragal us, ganoderm lucidum and lyceum, which are commonly used to increase organism's immunity. Several earlier studies in vitro have indicated that astragal us polysaccharide (AP), ganoderm a lucidum polysaccharide (GLP) and lycium polyasacchride (LBP) has anti-aging activities, however the mechanism underlyling these activities was unclear and remained to be elucidated. In this study, according to the previous studies, using the zebra fish (Danio rerio) , we evaluated molecular mechanism of the effect of AP GLP and LBP on zebra fish apoptosis after 72 hpf (hours post fertilization), zebra fish embryos were exposed to different polysaccharide with the concentration of 0.125mg/ml, continuously for 3 days. The results of e-galactosidase (SA-e-gal) staining shows that all polysaccharide can delay zebra fish embryos apoptosis, especially for LBP showed significant variance compared with non-treated embryos. The differential gene expression of polysaccharide treated zebra fish embryos was examined by RT-PCR analysis. We found that the gene expression of mdm2 and tert were up-regulated while bax, p21 and p53 gene expression were down-regulated during early apoptosis of the zebra fish embryos mediated by AP, GLP and LBP, but there is no significant difference among the treatment. The results demonstrate that polysaccharide may have some function during the induction of senescence.