摘要Background Our previous study had demonstrated that ulinastatin (UTI) had a neureprotective effect in experimental autoimmune encephalomyelitis (EAE).Methylprednisolone has been recommended to be a standard drug in multiple sclerosis (MS) therapies.The present study was to investigate the protective effects of UTI combined methylprednisolone in EAE.Methods Mice were divided into a UTI treatment group,a methylprednisolone treatment group,a combined treatment group with UTI and methylprednisolone,a normal saline treatment group,and a normal control group.EAE mice were induced in groups receiving different combined treatments,or respective monotherapies.Demyelination was evaluated by Solochrome cyanin staining.2′,3′-cyclic nucleotide 3′-phosphodiesterase (CNP)/myelin basic protein (MBP)/the precursor form of nerve growth factor (proNGF)/p75/inducible nitric oxide synthase (iNOS) proteins in cerebral cortex of EAE were detected by Western blotting.Results The combined treatment group had a lower clinical score (0.61±0.06) and demyelinating score (1.33±0.33)than the groups with normal saline (clinical score:1.39±0.08,P ＜0.001; demyelinating score:2.75±0.49,P ＜0.05) or monotheraphies.Compared with the saline treated EAE group,UTI combined methylprednisolone significantly increased expressions of CNP (1.14±0.06 vs.0.65±0.04,P ＜0.001),MBP (1.28±0.14 vs.0.44±0.17,P ＜0.001),and decreased expressions of proNGF (1.08±0.10 vs.2.32±0.12,P ＜0.001),p75 (1.13±0.13 vs.2.33±0.17,P ＜0.001),and iNOS (1.05±0.31 vs.2.17±0.13,P ＜0.001) proteins in EAE.Furthermore,UTI combined methyiprednisolone could significantly upregulate MBP (1.28±0.14 vs.1.01±0.15,P ＜0.05) expression and downregulate iNOS (1.05±0.31 vs.1.35±0.14,P ＜0.05) expression compared to methylprednisolone treatment EAE group.And proNGF expression was significantly lower in combined treatment (1.08±0.10) than that in UTI (1.51±0.24,P ＜0.05) or methylprednisolone (1.31±0.04,P ＜0.05)treatment group.Conclusion Combination treatment of UTI with methylprednisolone was shown to protect EAE,suggesting that combination therapy is a potential novel treatment in MS.