The Study Of The Effect On Klotho-akt And Its Downstream Molecular Of The Aging Wistar Rats’ Hippocampus By Polysaccharides

Objective: To observe the effect on the learning and memory ability of aging Wistar rats by Polysaccharides,we discussed the relationship between the molecular mechanisms of improving learning and memory ability on aging Wistar rats by Polysaccharides and the expression of Klotho and its downstream molecular Akt, Foxo3 a, Mn-sod in hippocampus, to explain the impact of the degenerative changes in aging Wistar rat brain by Polysaccharides.Methods:We used Morris water maze to detect the learning and memory ability of aging Wistar rats,including 10 young Wistar rats and 42 natural aging Wistar rats. Among those rats,whose learning and memory ability that relatively reduced by 15%-30% in the control of young group were randomly divided into aging group, water decoction group and polysaccharide group. Aging group were gavaged by saline with 2ml / kg / d for 42 days continuously;Decoction group and polysaccharide group were gavaged by 3.14 g crude drug / kg / d(polysaccharide group were gavaged by0.175 g polysaccharide / kg / d) for 42 days continuously;After the last gavage,we detected the learning and memory ability of each group. RT-PCR was used to detect the level of m RNA expression of Klotho, Akt, Foxo3 a, Mnsod;And we detect the level of protein expression of Klotho and Mn-SOD by using immunohistochemistry.Results: Compared with the youth group, the learning and memory abilities significantly decreased in aging group, polysaccharide group and decoction group(p<0.01,p<0.01, p<0.01;p<0.01,p<0.01, p<0.01);The m RNA expression levels of Klotho, Foxo3 a and Mn-sod were significantly reduced(p<0.01, p<0.01, p<0.01;p<0.01,p<0.05,p<0.05;p<0.01,p<0.01,p<0.01);the protein expression levels of Klotho and Mn-SOD were also reduced(p<0.01,p<0.01,p<0.01;p<0.01,p<0.05,p<0.01),but the protein expression level of Akt was significantly increased(p<0.01,p<0.05,p<0.01). Compared with the aging group, the learning and memory ability of polysaccharide group and decoction group in rats was significantly improved( p < 0.01,p < 0.01;p < 0.01,p < 0.01), the m RNA and protein expression level were significantly increased in Klotho and Mn-sod(p<0.01,p<0.01,p<0.01,p<0.01;p<0.01,p<0.01,p<0.01,p<0.01),the m RNA expression of Foxo3 a was significantly increased(p<0.01, p <0.01);But the Akt m RNA expression was significantly reduced(p<0.01, p<0.05). Correlation analysis showed that, Klotho m RNA and protein expression were both positively correlated with space exploration capability(R=0.68339,p<0.0001;R=0.72356,p <0.0001);Klotho m RNA and protein expression was also positively correlated with Mn-SODm RNA and protein expression, respectively(R=0.81486,p <0.0001;R=0.75774,p<0.001); But Klotho m RNA expression was significantly negatively correlated with Akt m RNA expression(R=-0.71586,P<0.0001); Klotho m RNA expression was positively correlated with Foxo3 a m RNA expression(R=0.74885,P<0.0001).Conclusion: These genes were correlated with learning and memory ability of aging Wistar rats; Dogwood polysaccharides and its water decoction could improve learning and memory ability of aging Wistar rats by increasing the expression of Klotho and Mn-SOD, decreasing the Mrna expression of Akt and upregulating the m RNA expression of Foxo3a;There is no significant difference in the improvement of learning and memory abilities between dogwood polysaccharides and its water decoction,but the effect of polysaccharides was better than water decoction in increasing the m RNA expression of Klotho and Mnsod,polysaccharide is the important part of dogwood in anti-aging.