Methylation of Interleukin-1 receptor-associated kinase-3 and the risk of multiple sclerosis relapse/activity

Area of Science:

• Neuroimmunology
• Epigenetics
• Biomarker Discovery

Background:

• Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system.
• Epigenetic modifications, such as DNA methylation, are implicated in the pathogenesis of autoimmune diseases.
• Interleukin-1 receptor-associated kinase-3 (IRAK-3/IRAK-M) plays a role in immune regulation, and its silencing via methylation is investigated here.

Purpose of the Study:

• To investigate the association between IRAK-3 methylation and multiple sclerosis (MS) disease activity.
• To evaluate IRAK-3 methylation as a potential biomarker for predicting MS relapse.
• To explore the relationship between IRAK-3 methylation, IRAK-3 mRNA expression, MyD88, and NF-κB activity in MS patients.

Main Methods:

• Retrospective cross-sectional study involving 90 participants: 45 with active MS, 45 with MS in remission, and 45 healthy controls.
• Quantification of IRAK-3 methylation index (MI%), IRAK-3 mRNA levels, circulating myeloid differentiation factor 88 (MyD88), and nuclear factor-kappa B (NF-κB) activity.
• Statistical analysis including correlation and logistic regression modeling to assess predictive value.

Main Results:

• IRAK-3 MI% was significantly elevated in active MS patients compared to those in remission.
• Higher IRAK-3 MI% correlated with lower IRAK-3 mRNA expression, increased MyD88, and heightened NF-κB activity.
• A logistic regression model incorporating IRAK-3 methylation demonstrated a strong predictive capability (C-index = 0.924) for active demyelination.

Conclusions:

• IRAK-3 methylation is significantly associated with active multiple sclerosis.
• IRAK-3 methylation serves as a promising candidate biomarker for identifying MS patients at risk of relapse.
• Epigenetic silencing of IRAK-3 may contribute to MS pathogenesis through modulation of the MyD88/NF-κB pathway.