Abstract: Objective: To study the effects of curcumin on the cognitive function and Toll-like receptor 4/nuclear transcription factor-κB (TLR4/NF-κB) pathway in hippocampus tissue of the mice with sleep deprivation, and to explore the mechanism of curcumin in the treatment of sleep deprivation. Methods: A total of 100 mice were randomly divided into control group, model group and low,middle, high doses of curcumin groups,and there were 20 mice in each group.Except control group,the mice in the other groups were established sleep deprivation models by modified multi-platform water environment sleep deprivation method;after modeling, the mice in low, meddle and high doses of curcumin groups were intraperitoneally injected with 5, 10, and 20 mg·kg^-1 curcumin, once a day for 3 d. Morris water maze test was used to determine the learning and memory abilities of the mice in various groups,and open-field test was used to determine the rearing and crossing scores of the mice in various groups; the levels of interleukin-1β (IL-1β) and interleukin-6 (IL-6) in the hippocampus tissue of the mice in various groups were detected by ELISA method, the expression levels of TLR4 and NF-κB p65 proteins in hippocampus tissue of the mice in various groups were detected by Western blotting method, and the expression levels of IL-1β, IL-6, TLR4, and NF-κB mRNA in hippocampus tissue of the mice in various groups were detected by RT-PCR method. Results: Compared with model group, the escape latencies of the mice in different doses of curcumin groups were shortened (P<0.05), the time of staying on the original platform quadrant was prolonged(P<0.05), the times of crossing the original platform were increased (P<0.05), the rearing and crossing scores of the mice in open-field test were decreased (P<0.05),the expression levels of IL-1β, IL-6, TLR4 and NF-κB p56 proteins in hippocampus tissue of the mice in various groups were significantly decreased (P<0.05),and the expression levels of IL-1β, IL-6, TLR4 and NF-κB mRNA in hippocampus tissue of the mice in various groups were decreased(P<0.05). Conclusion: Curcumin may improve the cognitive function in the mice with sleep deprivation by inhibiting the TLR4/NF-κB pathway.

Key words: curcumin, sleep deprivation, cognitive function, hippocampus, Toll-like receptor 4, nuclear transcription factor-κB, interleukin-1β, interleukin-6