Epigenetics of autoimmune disorders

Overview of the role of epigenetics in autoimmune disorders

Epigenetics and Autoimmune Disorders

Discoid lupus erythematosus

Epigenetics refers to heritable changes in gene expression that do not involve alterations to the underlying DNA sequence. These changes can affect how cells read genes and are crucial in regulating various biological processes. In the context of autoimmune disorders, epigenetic modifications can influence the immune system's ability to distinguish between self and non-self, potentially leading to the development of autoimmune diseases.

Mechanisms of Epigenetic Regulation

Epigenetic regulation involves several mechanisms, including DNA methylation, histone modification, and non-coding RNAs. These mechanisms can alter chromatin structure and gene expression patterns, impacting immune cell function and contributing to the pathogenesis of autoimmune disorders.

DNA Methylation

DNA methylation involves the addition of a methyl group to the cytosine residues in DNA, typically leading to gene silencing. Aberrant DNA methylation patterns have been observed in various autoimmune diseases, such as systemic lupus erythematosus (SLE) and rheumatoid arthritis.

Histone Modification

Histone proteins can undergo various post-translational modifications, such as acetylation, methylation, and phosphorylation. These modifications can influence chromatin structure and gene expression. In autoimmune disorders, dysregulated histone modifications can lead to inappropriate activation or repression of immune-related genes.

Non-coding RNAs

Non-coding RNAs, including microRNAs and long non-coding RNAs, play a role in regulating gene expression at the post-transcriptional level. Altered expression of non-coding RNAs has been implicated in the pathogenesis of autoimmune diseases by affecting immune cell differentiation and function.

Epigenetic Changes in Specific Autoimmune Disorders

Psoriasis on elbow

Systemic Lupus Erythematosus

In SLE, global DNA hypomethylation and specific hypermethylation of certain genes have been reported. These changes can lead to the overexpression of genes involved in immune activation and inflammation.

Rheumatoid Arthritis

Rheumatoid arthritis is associated with altered DNA methylation patterns in synovial fibroblasts and immune cells, contributing to chronic inflammation and joint damage.

Psoriasis

Psoriasis is characterized by abnormal histone modifications and altered expression of non-coding RNAs, which can lead to the dysregulation of keratinocyte proliferation and immune responses.

Alopecia Areata

Alopecia areata bald spot

In alopecia areata, changes in DNA methylation and histone modifications have been observed, affecting hair follicle immune privilege and leading to hair loss.

Potential Therapeutic Implications

Understanding the role of epigenetics in autoimmune disorders opens up new avenues for therapeutic interventions. Epigenetic therapies, such as DNA methyltransferase inhibitors and histone deacetylase inhibitors, are being explored for their potential to modulate immune responses and treat autoimmune diseases.

Related Pages

• Autoimmune disease
• Epigenetics
• Systemic lupus erythematosus
• Rheumatoid arthritis
• Psoriasis
• Alopecia areata