Biological Effects Of Metasilicate-rich Natural Mineral Water

Objective To explore and evaluate potential biological effects of metasilicate-rich mineral water(MRMW) on survival time, blood glucose balance, blood lipid metabolism, anti-fatigue and hypoxia tolerance, learning and memory, antioxidant capacity, nonspecific immunity and hepatic and renal structure-function in experimental animal.Methods Firstly, water quality, including general parameters, cationic and anionic parameters, were analyzed for MRMW. Subsequently, in comparison of pure water, a series of animal experiments were conducted for MRMW as follows.1. Survival time: Moina macrocopa and ICR mice were served as experimental animals and their survival time were observed and recorded. 2. Blood glucose balance: ICR mice were served as experimental animals. Water intake, food intake and blood glucose were monitored periodically during the course of the experiment.After 90 days, an oral glucose tolerance test(OGTT) was carried out. Then serum biochemical indexes, indicators related to small intestinal glucose absorption and hepatic glycogen storages were measured. 3. Blood lipid metabolism: ICR mice were served as experimental animals. The body weight was monitored periodically during the course of the experiment. After 90 days, Lee’s index, fat coefficient,blood lipid level, bile composition and hepatic enzyme activity related to lipid metabolism were determined.4. Anti-fatigue and hypoxia tolerance: ICR mice were served as experimental animals. After 90 days, weight loading swimming and hypoxia tolerance tests were carried out and post-swimming serum biochemical indexes were analyzed. 5. Learning and memory: ICR mice were served as experimental animals. After 90 days, Morris water maze and passive avoidance tests were conducted and hippocampal neurotransmitters related to learning and memory were measured. 6. Antioxidation in vitro and in vivo: free radicals scavenging capability of water in vitro was measured. Simultaneously, ICR mice were served as experimental animals. After 90 days, antioxidant indexes in brains,hearts, livers and kidneys were determined. 7. Nonspecific immunity: ICR mice were served as experimental animals. After 60 days, carbon clearance and peritoneal macrophage phagocytosis tests were carried out. 8. Hepatic and renal structure-function: ICR mice were served as experimental animals. After 90 days,serum biochemical indexes were measured and hepatic and renal morphological changes were observed.Results 1. Water quality analysis: MRMW was slightly alkaline and had some soluble constituents and appropriate hardness. It contained several elements such as sodium, potassium, calcium, magnesium and silicon. Particularly, Metasilicate content was measured up to 90.75 mg/L. Moreover, the main anion in MRMW is bicarbonate. 2. Survival time: The average survival time of Moina macrocopa was longer in the MRMW group than in the control group(P<0.05). However, there was no significant difference in ICR mice between the two groups. 3. Blood glucose balance: In the course of OGTT, glucose levels at 30 min were higher in the MRMW group than in the control group(P<0.05). Compared with the control group, a remarkable increase of fasting blood glucose and glycosylated serum protein levels, enterocyte Na+-K+-ATPase activities as well as hepatic glycogen stores was observed in the MRMW group(all P<0.05). 4. Blood lipid metabolism:There were no significant differences in all indicators regarding blood lipid metabolism between the control group and the MRMW group in this experiment. 5.Anti-fatigue and hypoxia tolerance: All indicators regarding anti-fatigue and hypoxia tolerance did not differ between the control group and the MRMW group in this trail. 6. Learning and memory: In the probe trial, the swimming time of the targeted quadrant was significantly longer in the MRMW group than in the control group(P<0.05). In the passive avoidance test, the testing latency was significantly longer in the MRMW group than in the control group(P<0.05), as the frequency of electric shock and the percentage of animals showing errors in the MRMW group were obviously less than those in the control group(both P<0.05). Compared with the control group, a significant increase of acetylcholine concentration and a significant decrease of acetylcholinesterase activity were observed in the MRMW group(both P<0.05). 7. Antioxidation: Scavenging rates of hydroxyl radicals and superoxide anion radicals of MRMW were higher than those of pure water(both P<0.05). Compared with the control mice, a significant decrease of malondialdehyde content and significant increases of total antioxidant capacity,inhibition capacity of hydroxyl radicals and activity of superoxide dismutase,catalase and glutathione peroxidase were only observed in kidneys of the MRMW-treated mice(all P<0.05). However, nuclear factor erythroid 2-related factor 2 contents in kidneys did not show any difference between two groups. 8.Nonspecific immunity: There were no significant differences in all indicators regarding nonspecific immunity between the control group and the MRMW group in this trial. 9. Hepatic and renal structure-function: Hepatic and renal structure-function did not differ between the control group and the MRMW group in this trial.Conclusion Firstly, MRMW is a premium drinking water and has a life-prolonging effect on lower animals but not higher animals. Secondly, chronic intake of MRMW is apparently effective in increasing blood glucose concentration and promoting intestinal glucose absorption and liver glycogen storage in mice.Thirdly, long-term intake of MRMW is beneficial to memory in mice. Lastly,MRMW owns antioxidant capacity in vitro and improves the renal antioxidation in mice to some extent.