Cortistatin is a cyclic-
neuropeptide produced by brain cortex and immune cells that shows potent anti-inflammatory activity. In this article, we investigated the effect of
cortistatin in two models of
experimental autoimmune encephalomyelitis (EAE) that mirror chronic and
relapsing-remitting multiple sclerosis. A short-term systemic treatment with
cortistatin reduced clinical severity and incidence of EAE, the appearance of inflammatory infiltrates in spinal cord, and the subsequent
demyelination and axonal damage. This effect was associated with a reduction of the two deleterious components of the disease, namely, the autoimmune and inflammatory response.
Cortistatin decreased the presence/activation of encephalitogenic Th1 and Th17 cells in periphery and nervous system, and downregulated various inflammatory mediators, whereas it increased the number of regulatory T cells with suppressive effects on the encephalitogenic response. Moreover,
cortistatin regulated glial activity and favored an active program of neuroprotection/regeneration. We further used
cortistatin-deficient mice to investigate the role of endogenous
cortistatin in the control of immune responses. Surprisingly,
cortistatin-deficient mice were partially resistant to EAE and other inflammatory disorders, despite showing competent inflammatory/autoreactive responses. This unexpected phenotype was associated with elevated circulating
glucocorticoids and an anxiety-like behavior. Our findings provide a powerful rationale for the assessment of the efficacy of
cortistatin as a novel multimodal therapeutic approach to treat
multiple sclerosis and identify
cortistatin as a key endogenous component of neuroimmune system.