Modification of the FoxP3 Transcription Factor Principally Affects Inducible T Regulatory Cells in a Model of Experimental Autoimmune Encephalomyelitis

Alpinia oxyphylla is a traditional Chinese medicine widely used for treating diarrhea, ulceration, and enuresis. Moreover, A. oxyphylla is effective for cognitive function improvement and nerve regeneration. Multiple sclerosis (MS) is a chronic neuronal inflammatory autoimmune disease that commonly affects young adults in high-latitude regions. The aim of this study was to evaluate the beneficial effects of A. oxyphylla in an experimental autoimmune encephalomyelitis (EAE) mouse model, which is an extensively used model for human MS. The ethanolic extract of A. oxyphylla fruit (AO-1) was orally administered to EAE mice. Our results showed AO-1 significantly reduced EAE symptoms. Histopathological analysis showed AO-1 reduced demyelination, inflammation, gliosis, and axonal swelling in the spinal cord. Furthermore, immunohistochemistry and quantitative polymerase chain reaction (qPCR) studies revealed that the infiltration of CD4+, CD8+ T cells, and CD11b+ monocytes into the spinal cord decreased in the AO-1-treated group. Mechanistically, the Th1 transcription factor T-bet, Th17 transcription factor retinoic acid receptor–related orphan receptor γ (RORγt), and inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17 were reduced in the spinal cords of mice treated with AO-1. The expression levels of T-bet and RORγt were also lowered in the spleens of those mice. Further in vitro study showed AO-1 inhibited production of IFN-γ, IL-2, and tumor necrosis factor-α from MOG35-55-peptide-stimulated splenocytes. One component isolated from AO-1, yakuchinone A, inhibited IL-17 production in vitro and reduced EAE symptoms in the mice. Collectively, our results indicate that AO-1 ameliorated the severity of EAE in mice and may involve the regulation of Th1/Th17 response. A. oxyphylla warrants further investigation, particularly regarding its clinical benefits for MS.

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Role of Immune Cells in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

10.20944/preprints202011.0477.v1 ◽

2020 ◽

Author(s):

Sarah Dhaiban ◽

Mena Al-Ani ◽

Noha Mousaad Elemam ◽

Mahmood H Al-Aawad ◽

Zeinab Al-Rawi ◽

...

Keyword(s):

Multiple Sclerosis ◽

Experimental Autoimmune Encephalomyelitis ◽

Immune Cells ◽

T Regulatory Cells ◽

Cell Types ◽

Autoimmune Encephalomyelitis ◽

The Central Nervous System ◽

Chronic Autoimmune Disease ◽

Experimental Autoimmune

Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS) characterized by varying degrees of demyelination of uncertain etiology, and is associated with specific environmental and genetic factors. Upon recognition of CNS antigens, the immune cells initiate an inflammatory process which leads to destruction and deterioration of the neurons. Innate immune cells such as macrophages, dendritic cells and natural killer cells are known to play critical roles in the pathogenesis of MS. Also, the activation of peripheral CD4+ T cells by CNS antigens leads to their extravasation into the CNS causing damages that exacerbates the disease. This could be accompanied by dysregulation of T regulatory cells and other cell types functions. Experimental autoimmune encephalomyelitis (EAE) is a mouse model used to study the pathophysiology of MS disease. In this review, we highlight the roles of innate and adaptive immune players in the pathogenesis of MS and EAE.

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