BACKGROUND: Myasthenia gravis (MG) is a progressive autoimmune disorder caused by the production of antibodies directed against acetylcholine receptors (AChRs), resulting in muscle weakness and fatigue. This study aimed to explore the effect and mechanism of grilled nux vomica (GNV) in experimental autoimmune myasthenia gravis (EAMG) rats.

MATERIAL AND METHODS: Rat 97–116 peptides were used to mediate disease in the EAMG model in SPF female Lewis rats. The treatment groups received grilled nux vomica (75 mg/kg, 150 mg/kg, and 225 mg/kg). The autoantibody and inflammatory cytokines levels were measured by enzyme-linked immunosorbent assay (ELISA). RNA profiling was performed on high-dose and model group rats. Profiling results and TLR-4/NF-κB signaling were validated by q-PCR and Western blot analysis.

RESULTS: The results showed that GNV could attenuate the symptoms of EAMG rats. There was a decreased level of AChR-ab, IFN-γ, TNF-α, IL-2, IL-4, and IL-17 levels, and an increased level of TGF-β1. In total, 235 differentially expressed genes (DEGs), consisting of 175 upregulated DEGs and 60 downregulated DEGs, were identified. Functional annotation demonstrated that DEGs were largely associated with leukocyte cell–cell adhesion, NF-kappa B signaling pathway, muscle contraction, and cardiac muscle contraction pathway. Rac2, Itgb2, Lcp2, Myl3, and Tnni1 were considered as hub genes with a higher degree value in the protein–protein interaction (PPI) network. The q-PCR and Western blot results of hub genes were consistent with RNA profiles. GNV treatment also significantly reduced the TLR-4 and NF-κB p65 protein expression in EAMG rats.

CONCLUSIONS: These results indicate that grilled nux vomica ameliorates EAMG by depressing the TLR-4/NF-κB signaling pathway, and hub genes may serve as potential targets for MG treatment.

Keywords: Muscle, Skeletal, Myasthenia Gravis, Autoimmune, Experimental, Drugs, Chinese Herbal, Gene Expression Regulation, RNA, Messenger, RNA-Seq, Rats, Inbred Lew, Specific Pathogen-Free Organisms, Strychnos nux-vomica