[Effects of cerium oxide nanoparticles on cognitive function in 48 h sleep deprived male mice].

OBJECTIVE: To study the effects of cerium oxide nanoparticles( CeO_2 NPs)on cognitive function in 48 hours of sleep deprived male mice and explore its mechanism.

METHODS: Thirty-six healthy clean ICR male mice( four weeks old) were randomly divided into 6 groups: blank control group, solvent control group, sleep deprivation control group, low, medium and high dose groups of CeO_2 NPs. 1 m L of distilled water were given to mice of blank group, 1 m L of solvent were given to mice of solvent control and sleep deprivation control group, 1 mL of CeO_2 NPs solvent( 4, 8, 16 mg/kg) were administered to mice of low, medium and high dose groups of CeO_2 NPs. Each group of mice received intragastric administration for 30 days. On the 31 st day, a single platform water environment method was used for 48 hours of sleep deprivation on mice. Then, the cognitive ability of the mice was tested by Y-maze. Further, the antioxidant( CAT, MDA, T-AOC) and neurotransmitters( NO, Glu) in mice brain tissue were measured also.

RESULTS: Compare with the solvent control group, 48 hours of sleep deprivation reduced the cognitive ability of mice [( 36 ± 2) times vs. ( 20 ± 2) times, P = 0. 0006; 10. 753%± 0. 031% vs. 24. 927% ± 0. 972%, P = 0. 00000045 ], CAT activity [( 78. 151 ±17. 683) nmol/mg prot vs. ( 198. 155 ± 14. 437) nmol/mg prot, P = 0. 0008]and the level of T-AOC [( 103. 630 ± 24. 209) U/mg prot vs. ( 264. 599 ± 50. 223) U/mg prot, P =0. 007], but improved the content of MDA [( 9. 499 ± 1. 249) nmol/mg prot vs. ( 6. 157± 0. 373) nmol/mg prot, P = 0. 0113 ], NO [( 11. 608 ± 1. 281) μmol/mg prot vs. ( 3. 628 ± 1. 064) μmol/mg prot, P = 0. 001]and Glu[( 4. 731 ± 0. 131) μg/mg prot vs. ( 4. 476 ± 0. 126) μg/mg prot, P = 0. 03] in the brain. Low, medium and high dose Ce O2 NPs enhanced cognitive performance of the sleep deprived mice. Among three dose groups, the medium dose groups most significantly improved the cognitive ability of mice[( 27 ± 2) times vs. ( 36 ± 2) times, P = 0. 005; 18. 743% ± 0. 245% vs. 10. 753% ±0. 031%, P = 0. 0000006 ], increased CAT activities [( 238. 065 ± 19. 393) nmol/mg prot vs. ( 78. 151 ± 17. 683) nmol/mg prot, P = 0. 00045] and T-AOC levels [( 210. 516± 11. 339) U/mg prot vs. ( 103. 630 ± 24. 209) U/mg prot, P = 0. 002], decreased MDA[( 6. 528 ± 1. 162) nmol/mg prot vs. ( 9. 499 ± 1. 249) nmol/mg prot, P = 0. 039], NO[( 5. 651 ± 0. 239) μmol/mg prot vs. ( 11. 608 ± 1. 281) μmol/mg prot, P = 0. 001]and Glu levels [( 4. 358 ± 0. 016) μg/mg prot vs. ( 4. 731 ± 0. 131) μg/mg prot, P = 0. 008].

CONCLUSION: Ce O2 NPs can improve the cognitive ability of sleep deprived male mice, improve the antioxidant capacity of brain, reduce free radical damage to the nerves of brain, and regulate the neurotransmitters of brain.