Circulating miR20a5p and miR1495p as Inflammatory Biomarkers for Early Detection of Type 2 Diabetes Mellitus and PreDiabetes
Background: Chronic low‑grade inflammation plays a central role in the development and progression of type 2 diabetes mellitus (T2DM). MicroRNAs (miRNAs) have emerged as promising regulators of inflammatory pathways and potential non‑invasive biomarkers for early disease detection. This study aimed to investigate the expression levels of miR‑20a‑5p and miR‑149‑5p and their association with pro‑inflammatory cytokines in individuals with T2DM, pre‑diabetes, and non-diabetics. Methods: A total of 90 participants were enrolled and divided into three groups: non-diabetic (n=30), pre‑diabetic (n=30), and T2DM (n=30), according to the American Diabetes Association (ADA)’s criteria. Serum levels of miR‑20a‑5p and miR‑149‑5p were quantified using real‑time polymerase chain reaction (PCR). The expression levels and protein concentrations of inflammatory cytokines (IL‑6, IL‑1β, TGF‑β, and IFN‑γ) were assessed by real‑time PCR and enzyme-linked immunosorbent assay (ELISA), respectively. The receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic power of the selected miRNAs. Results: The expression of miR‑20a‑5p was significantly upregulated in both pre‑diabetic and T2DM groups, whereas the expression of miR‑149‑5p was significantly downregulated in the T2DM group. ROC analysis revealed excellent diagnostic power of miR‑20a‑5p for distinguishing T2DM (AUC=0.985) and pre‑diabetics (AUC=0.895) from non-diabetic controls. Elevated expression and serum levels of IL‑6, IL‑1β, TGF‑β, and IFN‑γ were observed in pre‑diabetic and T2DM groups. miR‑20a‑5p showed a significant positive correlation with pro‑inflammatory cytokines (P<0.001). while miR‑149‑5p demonstrated a significant negative correlation (P<0.001). Conclusion: The dysregulated expression of miR‑20a‑5p and miR‑149‑5p is closely associated with inflammatory responses in T2DM and pre‑diabetes. miR‑20a‑5p has higher diagnostic accuracy and may serve as a promising circulating biomarker for early detection of diabetes‑related metabolic and inflammatory alterations.