The Potential Roles of Omega Fatty Acids, Inflammation and Pre-miR-29c in Diabetic Nephropathy

Diabetic nephropathy (DN) is associated with inflammatory dysregulation and altered lipid mediators. We investigated inflammatory markers, fatty acids, and plasma pre-miR-29c in controls and type 2 diabetes mellitus (T2DM) patients stratified by albuminuria severity. This cross-sectional study included 120 T2DM patients (albumin-to-creatinine ratio, ACR: <30, 30–300, and >300 mg/g; n = 40 each) and 40 controls. TNF-α, IL-6, and lipoxin A4 (LXA4) were measured by ELISA; EPA, DHA, AA, and DGLA by LC–MS/MS; and plasma pre-miR-29c by semi-quantitative endpoint RT-PCR. TNF-α was higher in all T2DM groups compared with controls. LXA4 was lower in the ACR <30 and >300 mg/g groups, while IL-6 showed no significant difference. Compared with controls, EPA was lower in both albuminuric groups, DHA was lower, and AA was higher in all T2DM groups, while DGLA remained unchanged. Plasma pre-miR-29c increased with albuminuria severity and correlated strongly with the ACR (ρ = 0.852; FDR-adjusted p < 0.001). In the final Firth model, log2-transformed pre-miR-29c was the only variable that remained statistically associated with DN (OR = 170.692, 95% CI: 22.319–23,827.669; p < 0.001); the wide confidence interval reflects near-complete separation. These exploratory findings suggest that pre-miR-29c may serve as a candidate marker of albuminuria severity, requiring confirmation by quantitative PCR with validated normalisation in longitudinal cohorts.