Associations of miR-146a-5p and miR-31-5p with neuroinflammatory diseases

Aim: To evaluate the expression changes of miR-146a-5p and miR-31-5p molecules in the blood of patients with inflammatory polyneuropathy. Methods and Subjects: The expression of miR-146a-5p and miR-31-5p molecules was determined in the blood of patients with chronic inflammatory demyelinating polyneuropathy (CIDP, n = 13) and multifocal motor neuropathy (MMN, n = 10) and compared to a control group (n = 40). Blood samples for miRNA expression analysis were collected in specialized “Tempus™ Blood RNA Tubes.” RNA was purified from whole blood using the “mirVana™ miRNA Isolation Kit.” Complementary DNA (cDNA) synthesis was performed using the “TaqMan® Advanced miRNA cDNA Synthesis Kit.” The expression of microRNA molecules was determined by real-time PCR (RT-PCR), and the data were analyzed using the “ThermoFisher Cloud” platform. Statistical analysis was performed using the “IBM SPSS 29.0” software. Results: The ∆CT values of miR-146a-5p and miR-31-5p were compared between the inflammatory polyneuropathy (IPN) and control groups. It was found that the expression of miR-146a-5p significantly differed between the IPN and control groups (p = 0.014). The control group showed higher expression of miR-146a-5p (mean -∆Ct = -9.088) compared to the IPN group (mean -∆Ct = -9.588). Additionally, the ∆CT values of miR-146a-5p and miR-31-5p were compared among the two diseases: CIDP, MMN, and the control group. Analysis of the obtained data confirmed that the ∆CT values of miR-146a-5p significantly differed between the groups (p = 0.047). Conclusion: The expression of miR-146a-5p and miR-31-5p molecules was statistically significantly lower compared to the control group.