Protective Effects Of Pre-germinated Brown Rice Diet On Low-levels Of Pb Induced Damages In Developing Rat

Objective: Lead is a toxic heavy metals which is non-degradable and ubiquitous in the environment. Humans and animals can get lead to absorb and accumulate in the body through the soil, air, food, water and other contacts. Lead might damage the nervous, hematopoietic system and other organ and be particularly sensitive to childhood. There is still a lack of effective methods of treatment of lead poisoning which is still a public health problem of global concern. Pre-germinated brown rice is rich in vitamins, dietary fiber, a variety of antioxidant substances and trace elements. Therefore the study intent to establish animal model that development rats drink water with lead acetate and eat different ingredients such as pre-germinated brown rice, then to observe the protective effects of pre-germinated brown rice against Pb accumulation in the body induced pathological, oxidative and DNA damage in rats, to explore a intervention therapy and effective method of preventing and treating lead poisoning.Methods: 1 Establishment of animal model: 120 healthy and weaning SD rats were randomly divided into 1 control group and 4 treatment groups, 24 each group. The control group of animals drink de-ionized water and eat a standard diet(AIN93G).The treatment groups drink the water with 2g / L of Pb(CH3COO)2 and eat the standard diet, white rice, brown rice, pre-germinated brown rice. Animals were sacrificed after 40 days of feeding and collected the tissues to detect for the related experiment. 2 Determination of the contents of Pb in tissue of rat: the Pb levels in hippocampus, liver and kidney of rats were measured by atomic absorption spectrophotometry.3 Histopathological observation: The pathology changes of tissue structure were observed under light microscopy by making brain, liver and kidney tissue pathological slices. 4 Measurement of tissue oxidative stress state: The activities of anti-oxidase glutathione peroxidase(GSH-Px) and superoxide dismutase(SOD), and the levels of malonaldehyde(MDA) in hippocampus, liver and kidney tissues of rat were determined using biochemical methods. 5 Determination of DNA damage: The olive tail moment(OTM) and Tail DNA% in hippocampus, cortex, liver and kidney tissue cells of rat were determined using the single cell gel electrophoresis experiment(SCGE).Results: 1 The general status of rats In the process of feeding animal models, all rats were survived. Rats drink and eat freely with weight gradually increased. At the initial feeding, the rats were normal with no significant difference in the amount of food and water and feces, urine traits; at the post feeding, lead acetate group reduced the amount of food and water, slow weight gaining, fewer activities compared with the control group of rats. 2 The changes of feeding different diet on Pb contents in tissue of rats Compared to control group, Pb contents for the remaining four groups rats drinking water with Pb AC in the hippocampus, liver and kidney tissues were significantly increased(P<0.05); Compared with Pb AC group, Pb contents of Pb AC+BR and Pb AC+PBR groups rats in hippocampus, liver and renal tissues were significantly reduced(P<0.05). 3 The pathological changes of feeding different diet in hippocampus, cortex, liver and kidney tissue of rats In Pb AC group, irregular shape and arrangement disorder cells with color darker, shrinkage, spindle, triangular nuclear in the hippocampus CA1 disorder and cortical pyramidal cells layers were presented significant increased. The cells around the central vein arranged disorder and appeared point or necrosis; cell boundaries were unclear; morphological changed;normal lobular decreased or disappeared; cytoplasm occurred dissolution and vacuoles; nuclear shrinkage and heterochromatin increased in liver tissue. Renal wall cell boundaries were unclear partially; cytoplasm occurred dissolution, vacuoles, point or necrosis; cell structural were damaged; renal proximal tubule epithelial cell were degeneration or loss with protein-like floss deposition in the large lumen in kidney tissue. Pb AC+PBR group pathological changes were significantly relieved compared with Pb AC group. 4 The changes of feeding different diet on oxidative stress in tissue of rats 4.1 The changes of GSH-Px activity in the cells of rats The GSH-Px activity in the hippocampus of rats in Pb AC, Pb AC+WR, Pb AC+BR and Pb AC+PBR groups were significantly reduced compared with the control(P<0.05). The GSH-Px activity in the liver and kidney of rats in Pb AC, Pb AC+WR, Pb AC+BR groups were significantly reduced compared with the control(P <0.05); The GSH-Px activity in the liver and kidney of rats in Pb AC+BR and Pb AC+PBR groups were significantly increased compared with the Pb AC(P <0.05). 4.2 The changes of SOD activity in the cells of rats The SOD activity in the hippocampus of rats in Pb AC, Pb AC+WR, Pb AC+BR groups were significantly reduced compared with the control(P <0.05); The SOD activity in the hippocampus of rats in Pb AC+BR and Pb AC+PBR groups were significantly increased compared with the Pb AC(P <0.05). The SOD activity in the liver and kidney of rats in Pb AC, Pb AC+WR groups were significantly reduced compared with the control(P<0.05); The SOD activity in the liver and kidney of rats in Pb AC+BR and Pb AC+PBR groups were significantly increased compared with the Pb AC(P<0.05). 4.3 The changes of MDA level in the cells of rats The MDA level in the hippocampus and kidney were not significantly different between grous.The MDA level in the liver of rats in Pb AC were significantly increased compared with the control(P<0.05); The MDA level in the liver of rats in Pb AC+WR, Pb AC+BR and Pb AC+PBR groups were significantly reduced compared with the Pb AC(P<0.05). 5 The changes of feeding different diet on DNA damage in cell of rats Compared to control group, Tail DNA% and OTM values for the remaining four groups drinking water with Pb AC in the cells of hippocampus, cortex, liver and kidney tissues were significantly increased(P<0.05); Compared with Pb AC group, Tail DNA% and OTM values of Pb AC+BR and Pb AC+PBR in hippocampus, cortex, liver, and renal tissues were significantly reduced(P<0.05).Conclusions: 1 Pb accumulated in tissue of hippocampus,liver and kidney after drinking lead acetate water. The PBR diet might prevent the Pb accumulation in tissue some degree. 2 The PBR diet can reduce the pathological damage of hippocampus, cortex, liver and kidney induced by lead acetate in rats. 3 The PBR diet can improve the antioxidant ability of tissue and reduce the oxidative damage of multiplex organs by lead acetate in rats. 4 The PBR diet can reduce the cell DNA damage of multiplex tissues induced by lead acetate in rats.