Morphine Withdrawal-Induced Immunosuppression Modulates DNA Methylation in IEC18 cells

Morphine cessation is known to cause immunosuppression in chronic opioid users. Individuals are more susceptible to pathogenic infections during withdrawal, due to the depletion of circulating lymphocytes, macrophages, and cytokines. Morphine withdrawal can also alter the degree of methylation in DNA. Methylation of DNA is a heritable phenomena that does not change the sequence of the genome but can cause genes to be transcriptionally suppressed or enhanced. These changes in gene expression makes individuals more predisposed to acquiring a variety of pathologies. A known transcriptional enhancer of hypermethylated DNA segments is MeCP2. MeCP2 is a protein that binds methylated-CpG regions of DNA, resulting in downstream upregulation of immune determinant genes. An increase in MeCP2, indicates an upregulated immune response due to its association with activating signaling pathways such as NF-KB. Additionally, DNA methylation landscape is also altered in inflammatory bowel diseases, especially in ulcerative colitis. This study was undertaken to evaluate morphine withdrawal-induced DNA methylation modulations in rat intraepithelial cells-18 (IEC18). IEC18 cells were treated in a placebo withdrawal and morphine withdrawal. DNA and RNA was then extracted and evaluated for methylation through bisulfate conversion. Expression of MeCP2e1, GLS, and MOR in placebo and morphine withdrawn cells were assessed through PCR and gel electrophoresis. It was discovered that morphine withdrawal-induced immunosuppression altered the methylation of the genes tested. Indicating that there is permanent DNA change occurring with opioid withdrawal immunosuppression.