Effects of zinc-deficiency on antioxidation system and repair of DNA damage and of hepatic cells in aging mice / 中华老年医学杂志

ABSTRACT

Objective To observe the effects of zinc-deficiency(ZD)on antioxidation system and repair of DNA damage and of hepatic cells by establishing an aging mice model induced with D-galactose. Methods Seventy 3-month-old male mice were divided randomly into 5 groups normal young group, aging model group, aging+ZD group, aging+pair-fed group, aging+ZS group. The aging model were established with D-galactose (100mg/kg bw) by nap subcutaneous injection, while the young control group were injected with normal saline in the same way which lasted 30 days. Aging+ZD group and aging+ZS group were fed with ZD food(zinc 1.61?g/kg), others with normal food(zinc 50?g/kg). ZS food (zinc 100?g/kg)were given to aging+ZS group for the last 2 weeks in the course. On the 30 th day, all mice were killed by removing eyeballs and samples were collected immediately for later indexes detection. Results Compared with the aging control group, zinc contents and SOD activity of serum and liver decreased significantly, while MDA in the serum and liver and lipofuscin of liver increased much more in ZD mice. Comet assay also showed that the DNA damage of hepatic cells were more serious in aging ZD mice than in the control mice. The ratio of tail length/comet cell length in group ZD also increased significantly. However, moderate zinc supplement significantly improved all those indexes. Conclusions Zinc can affect the speed and degree of aging significantly. Zinc deficiency accelerates the aging progress; while moderate zinc supplement seems to be beneficial for retarding aging progress.