The Effects Of Mineral Water And Distilled Water On Oxidative Damages And Cognitive Decline Of Aged Mice

Objective: With the increasing degree of population aging,aging has become a serious social problem.In this experiment,we used aged mice as a model to investigate the effects of mineral water and distilled water on oxidative damage and cognitive decline in aged mice.Method: Ninety 48-week-old C57BL/6 female mice were adaptively fed for about a week,and then ten mice were randomly selected for baseline control group according to body weight.These 49-week-old mice in the baseline control group were killed before the beginning of this experiment.The remaining 80 mice were randomly divided into 4 groups,each with 20 mice,namely the cold boiled tap water group as the control group,distilled water group,mineral water group 1 and mineral water group 2.The experimental animals were free to eat and drink,and the feeding and drinking were recorded.We recorded the remaining water every other day,the remaining food every two days,and weigh the mice once a week.When the mice were fed to the 24 th week of the experiment(that is,the mice were 73 weeks old),10 mice were randomly selected from each of the 4 groups and killed.When the mice were fed until the 34 th week of the experiment(that is,the mice were 83 weeks old),the remaining 4 groups of mice were all killed.The mice were tested with 8-Arm Maze one week before being killed.The mice were fasted for12 hours,and two of 10 mice in each group were randomly selected for cardiac perfusion experiments,and their brain tissues were taken for hematoxylin-eosin staining sections to observe the structural changes in cognitive functional area of the hippocampus of mice.The remaining 8 mice in each group were decapitated after bloodletting from their eyeballs.The brain,heart,liver,kidney,spleen and other tissues were weighed and recorded to calculate the coefficient of each organ.Then the liver and brain samples were labeled and frozen in liquid nitrogen.Blood and tissue samples were used to detect oxidation indicators(SOD,MDA,GSH-Px and MAO)and cognitive function indicators(AChE and NOS activity).The expression of aging-related proteins SIRT1 and SIRT6 in tissue samples were detected with Western Blot method.Results: Oxidation indicators: Compared with the baseline,in the 73-week-old mice,serum SOD activity decreased,MDA content in the liver increased,and SOD activity and GSH-Px activity in the brain tissue decreased;in the 83-week-old mice,the activity of SOD both in the serum and liver decreases,the activity of SOD and GSH-Px in the brain tissue decreases,and the activity of MAO in the liver increases.Cognitive function indicators: Compared with the baseline,in the 73-week-old mice,the activity of AChE and NOS in the brain tissue decreases;in the 83-week-old mice,the activity of AChE in the brain tissue decreased.Pathological indicators: Compared with the baseline,the arrangement of cells in the DG area of the brain tissue of the73-week-old and 83-week-old mice gradually became loose,the number of cells in the CA1 area gradually decreased,and the arrangement was loose,and the cell arrangement in the CA3 area was also gradually loosened,and the nucleus was shrinking and the cells tended to be vacuolation.Serological indicators: Compared with the baseline,serum GOT and GPT activities were significantly higher in the83-week-old mice,and the serum CRE content increased.Compared with the control group(the cold boiled tap water group),the73-week-old mice in the distilled water group showed decreased activity of serum SOD,increased activity of MAO in the liver,and the 83-week-old mice showed increased activity of MAO in the.For both of the 83-week-old mice in the mineral water group 1 group 2,they showed a decreased level of MDA content in brain tissues.The GSH-Px activity in the liver and brain tissue of the 73-week-old mice in the mineral water group 1 increased.Compared with the control group,the NOS activity in the brain tissue of the83-week-old mice in the distilled water group decreased;The pathological results showed that the pyramidal cells in the CA3 area of the 73-and 83-week-old mice were loosely arranged,also,nuclear pyknosis and vacuolization in cells were observed.The cells in the CA3 area of the 83-week-old mice in the mineral water group 1 and the mineral water group 2 were arranged tightly,and no nuclear pyknosis and cell vacuolation were observed in the control group.The activity of AChE in the brain tissues of the 73-and 83-week-old mice in the mineral water group 1 increased;the results of the eight-arm radial maze showed that the number of working memory errors and the number of reference memory errors in the 83-week-old mice in the mineral water group 2 decreased significantly.Compared with the control group,the relative expression level of SIRT1 protein in the liver of the 73-week-old mice in the mineral water group 2 had a tendency to increase,and the relative expression level of SIRT6 protein in the brain tissue increased.Conclusion: With the increase of the experimental time,the physiological indicators of the aged mice showed senile changes,mainly manifested in oxidative damage and cognitive decline.Drinking distilled water for 24 and 34 weeks promotes the aging of the aged mice.Drinking both of the two kinds of mineral water can delay senescence,but the action characteristics of the two mineral waters are different.Mineral water 1 has better antioxidant effect and delayed cognitive decline.And mineral water 2 benefits learning and memory and induces the expression of aging related proteins.