The inhibition of Rho kinase blocks cell migration and accumulation possibly by challenging inflammatory cytokines and chemokines on astrocytes.

Multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE), are autoimmune diseases characterized by the immune-mediated demyelination and neurodegeneration of the CNS. Our previous studies showed that Rho kinase inhibitor Fasudil can delay onset, and ameliorate severity of EAE, accompanied by the improvement in myelination and the inhibition of inflammatory responses in the CNS. In this study, we found that Fasudil inhibited the migration of T cells indirectly by affecting the production of inflammatory factors and the expression of chemokines in astrocytes functions, indicating that Fasudil treatment reduced inflammatory cytokines such as TNF-α and IL-6, reactive oxygen species (NO) and chemokines like MIP-3α (CCL-20), RANTES (CCL5), MIP-1α (CCL-3) and MCP-1 (CCL2) in vitro, and blocked the chemotaxis of reactive mononuclear cells in EAE mice. Further studies found that Fasudil treatment reduced the infiltration and accumulation of pathogenic T cells into the CNS. Astrocytes expressing GFAP and CCL-20 were inhibited in Fasudil-treated EAE compared with control mice. These results demonstrate that Fasudil alleviates the pathogenesis of EAE possibly by blocking astrocyte-derived chemokine-mediated migration of inflammatory macrophages and pathogenic T cells, and might be used to treat MS.