Abstract： The study was designed to investigate the peripheral anti-inflammatory effect of nicotinamide riboside(NR)in experimental autoimmune encephalomyelitis(EAE)mice and its mechanisms.Female C57BL/6 mice were induced by MOG35-55 to prepare EAE model,which then randomly divided into EAE model group and NR treatment group.Mice in EAE model group were given normal saline at a dose of 200 μl/d and mice in NR treatment group were given NR at a dose of 500 mg/kg(200 μl/d)by intragastric administration.Clinical score and body weight of mice in each group were observed and recorded.After mice were sacrificed on the 28th day after immunization,frozen sections of spleen and spinal cord were prepared and proteins of spinal cord were extracted.HE staining was used to detect peripheral inflammatory cells infiltrating spinal cord;immunofluorescence staining was used to detect the number of CD4+T cells and CD68+macrophages in spinal cord of mice;Western blot was used to detect the expression of IFN-γ and IL-1β in spinal cord of mice;immunofluorescence staining was used to detect the number of ROCK-Ⅰ+cells,TLR4+cells,p-NF-κB+cells,TNF-α+cells,IL-1β+cells,IFN-γ+cells,IL-6+cells,IL-10+cells,IL-17+cells,iNOS+cells and Arg-1+cells in spleen of mice.Data showed that compared with EAE model group,NR significantly delayed the onset time of EAE mice(P<0.05),decreased clinical score(P<0.05 or P<0.01),alleviated weight loss,prevented peripheral inflammatory cells from infiltrating spinal cord,decreased the number of CD4+T cells and CD68+macrophages in spinal cord(P<0.01),down-regulated the expression of IFN-γ and IL-1β of spinal cord(P<0.05),inhibited the expression of ROCK-Ⅰ,TLR4 and p-NF-κB in spleen of mice(P<0.01),reduced the secretion of IFN-γ,iNOS,IL-6 and other pro-inflammatory factors in spleen(P<0.05 or P<0.01),and increased the secretion of anti-inflammatory factors Arg-1 and IL-10 in spleen(P<0.05 or P<0.01).In conclusion,NR can effectively alleviate the clinical symptoms of EAE mice and significantly reduce inflammatory response of peripheral and central nervous system,and its mechanism may be related to the inhibition of Rho/ROCK signaling pathway and TLR4/NF-κB signaling pathway in spleen of EAE mice.