Investigation of microRNA expression levels related to inflammation before and after budesonid treatment in crohn patients

Crohn's disease is a recurrent, chronic inflammatory disease of the digestive tract. It is thought that the immune system, environmental and genetic factors play a role in the formation of the disease, but its etiology is still unknown. MicroRNA (miRNA) molecules are non-coding RNA molecules that regulate cellular events such as cell proliferation, cell differentiation, organogenesis, apoptosis. It has been shown that abnormal miRNA expressions play a role in the etiology of many diseases, from cancer to neurodegenerative diseases. Studies have revealed that miRNAs are closely related to the regulation of inflammatory processes and the pathogenesis of inflammatory diseases. In this study, the expression levels of miR-744-3p, miR-320a and miR-17-5p associated with inflammation before and after treatment with budesonide in newly diagnosed Crohn's patients were determined, and its potential effects on the pathogenesis of the disease and the response to treatment were investigated. In our study, expression levels of miRNAs obtained from peripheral blood samples taken before and after budesonide treatment from 20 patients diagnosed with mildly active ileocecal Crohn's disease and from peripheral blood samples of 20 healthy control were determined by quantitative real-time polymerase chain reaction (qRT-PCR) method and statistically compared between groups. When the findings were evaluated, miRNA-744-3p, miRNA-17-5p and miRNA-320a expression levels of the Crohn's patient group before and after treatment with budesonide were found to be statistically significantly higher than the control group (p=0.000, p=0.000, p=0.004 before treatment, respectively; p=0.000 p=0.000 p=0.002 after treatment, respectively). There was no statistically significant difference between miRNA expression levels of the patient group before and after treatment (p>0.05). Our results suggest that miRNA-744-3p, miRNA-320a and miRNA-17-5p can be used as diagnostic specific biomarkers for Crohn's disease, but the lack of difference in expression levels before and after treatment suggests that these miRNAs are not associated with treatment response. Further studies in larger patient groups are needed to confirm the results of this study.