Studies Of The Zinc Chelating Chitooligosaccharides On Learning And Memory In Mice

The study on brain function has always been a hot research. Learning and memory is oneof the advanced features of the brain. Zinc is one of essential trace elements for animals, andclosely related to their growth、 development、learning and memory. Amino acid、organicacid、polysaccharide and other small molecules in animal feed constitute a certain amount oforganic matter with inorganic zinc to exhibite synergistic effect, so as to promote theabsorption of zinc and improve the utilization rate of Zn. Chitosan oligosaccharide (COS) isthe degradation of chitosan after polymerization degree of products of2~10, which is onlythe existence of a large number of alkaline amino oligosaccharide in nature. A large numberof active amino and hydroxyl groups in the molecule react with inorganic zinc, and formorganic chitooligosaccharide-zinc (COS Zn)by controlling the reaction conditionsObjective To investigate the effect of COS Zn on the growth and the ability of learningand memory in mice. Methods40healthy male and female Kunming mice were randomlydivided into control group、chitosan oligosaccharide group、 chitosan oligosaccharide+Zngroup and chelating group,10rats in each group. Measurement of body weight changes andfeed consumption per week.5weeks after the mated male and female, generation upongeneration weaned child after its sub-cage alone feeding. Select the30-day-old male micewere used in open field test, Y-maze test.9weeks old when the first generation of the brainwas weighed cerebral index calculated with Coomassie brilliant blue brain and hippocampuswere measured by protein content, and then use the catalyzed by xanthine oxidase (WST)activity of SOD enzyme determination of brain method, determination of content of MDA byTMB colorimetric method. Finally,we use paraffin section, HE staining of brain to observethe morphology of hippocampus. Results COS Zn (adding30mg\/kg, in terms of zinc) couldsignificantly increase the average daily intake of mice (P <0.05) and weekly weight; in theopen field test, COS Zn can improve the ability of exploration to the new environment inmice; in Y-maze test, chelating group significantly decreased learning times,(P <0.05),significantly increased memory (P <0.05); hippocampal protein content were significantlyincreased (P <0.05), chelating group SOD enzyme activity is better than the other threegroups, and compared with the control group had significant difference (P <0.05), the contentof MDA in chelating group are lower than the other three groups, and the other groupsshowed no significant difference (P>0.05); finally, we analyze the brain tissue sections,finding that chelating group’s hippocampus is the highest fullness; in the high-power microscopy we observed largest number of nucleus of chelating group, and the form is bigand round, capillaries closely arranged. Conclusion COS Zn can promote the growthand the ability of learning and memory in mice.