Morroniside ameliorates experimental autoimmune encephalomyelitis by regulating gut microenvironment, immune balance,

Taotao Jiang1, Shaopeng Zhai1, Ting Zheng1

  • 1The Department of Neurology, The Second Hospital of Lanzhou University, Lanzhou, 730030, China.

Insights

Morroniside, a natural compound, effectively treats experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis (MS). It reduces inflammation and nerve damage by modulating immune cells and inhibiting the NF-κB pathway, offering a promising therapeutic avenue for MS.

Area of Science:

  • Neuroscience
  • Immunology
  • Pharmacology

Background:

  • Multiple sclerosis (MS) is a chronic central nervous system disease with limited treatment options.
  • Experimental autoimmune encephalomyelitis (EAE) serves as a key animal model for studying MS pathogenesis.
  • Current MS therapies face challenges including high costs, side effects, and inability to reverse neurological damage.

Purpose of the Study:

  • To investigate the therapeutic potential and underlying mechanisms of morroniside in a mouse model of multiple sclerosis (EAE).
  • To evaluate morroniside's effects on neuroinflammation, immune cell balance, and central nervous system microstructure.
  • To elucidate the molecular targets and pathways modulated by morroniside in EAE.

Main Methods:

  • Administration of morroniside to EAE mice, followed by clinical assessments and weight monitoring.
  • Diffusion Tensor Imaging (DTI) to assess white matter integrity (corpus callosum, cerebellum).
  • Histopathology, flow cytometry, RT-qPCR, transcriptome analysis, Western blot (WB), and ELISA to evaluate immune responses, gene/protein expression, and signaling pathways.
  • Molecular docking to predict binding affinity between morroniside and target molecules.
  • Gut microbiota analysis.

Main Results:

  • Morroniside significantly delayed EAE onset, reduced clinical scores, and improved weight loss.
  • DTI revealed microstructural repair in the corpus callosum and cerebellum, with altered ADC, MD, RD, and FA values.
  • Histopathology confirmed reduced inflammatory infiltration and demyelination.
  • Morroniside modulated peripheral immune balance by downregulating Th1/Th17 cells and upregulating Treg cells.
  • Inhibition of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) and key pathway mediators (Tnfsf8, NF-κB) was observed.
  • Transcriptome analysis identified differentially expressed genes enriched in inflammatory and immune response pathways, including NF-κB and PI3K-AKT.
  • Molecular docking indicated strong binding of morroniside to Tnfsf8.
  • Morroniside improved gut microbiota dysbiosis in EAE mice.

Conclusions:

  • Morroniside demonstrates significant therapeutic effects in the EAE model, ameliorating clinical symptoms and neuropathology.
  • Its mechanism involves multi-target regulation, including peripheral immune balance, inhibition of NF-κB-mediated neuroinflammation via Tnfsf8, and gut microbiota modulation.
  • Morroniside represents a promising natural compound for further development as a treatment for multiple sclerosis.