Objective: To investigate the effect of vasoactive intestinal peptide (VIP) on the content of IL-17A in the brain tissue of experimental autoimmune encephalomyelitis (EAE) rats.
Method: 60 healthy Wistar female rats were randomly divided into normal control group, EAE control group, VIP low-dose control group and VIP high-dose control group. The EAE model is induced by myelin basic protein (MBP) + complete Freund's adjuvant (CFA). From the day of modeling, VIP 4mol/kg (0.2 mL) and 16mol/kg (0.8 mL) were intraperitoneally injected every other day to VIP low-dose and high-dose prevention groups. The normal control group and the EAE control group were given 0.8 mL of normal saline for 10 consecutive days. Observe the incidence of rats, use anti-glial fibrillary acidic protein antibody (GFAP) ELISA method to detect the changes in the content of IL-17A factor in brain tissue, and detect activation by immunohistochemistry.
Result: In the VIP treatment group, the onset latency at the peak of the disease was longer, the course of the disease was shorter, and the neurological dysfunction score (NDS) was reduced. Brain homogenate has reduced IL-17A content, activated astrocytes have reduced GFAP+ cell level, and there is a specific dose dependence between each dose group.
Conclusion: VIP protects EAE by reducing the content of IL-17A in brain tissue and inhibiting the activation of astrocytes.