NU12 - Urinary miRNA 126 is Elevated in Dogs with Immune Complex-Mediated Glomerulonephritis

Abstract: Background: Most proteinuric dogs with naturally occurring chronic kidney disease have one of three categories of glomerular disease, each with different treatment and prognostic considerations: immune complex-mediated glomerulonephritis (ICGN), glomerulosclerosis (GS), or amyloidosis (AMYL). Urinary microRNAs (miRs) have the potential to be non-invasive biomarkers of diagnostic value.< br>< br>Hypothesis/Objective: We hypothesized that urinary miR-126 would differentiate dogs with ICGN from GS and AMYL, and the expression of miRs-21, 182, and 486 would differentiate azotemic from non-azotemic dogs.< br>< br>Animals: Archived urine from 39 dogs with azotemic and non-azotemic glomerular disease (11 with AMYL, 11 with GS, 17 with ICGN) and 5 clinically healthy dogs were selected. ICGN dogs included 10 with membranous glomerulonephritis (MGN) and 7 with membranoproliferative glomerulonephritis (MPGN).< br>< br>Methods: Retrospective. Urinary miRs-126, 21, 182, and 486 were quantified using RT-PCR with global mean normalization. One-way ANOVA and Mann Whitney tests evaluated differences between disease groups (P < 0.05).< br>< br>Results: Regardless of azotemia status, urinary miR-126 was significantly higher in dogs with ICGN and GS than AMYL and healthy controls (P < 0.001) and in ICGN than GS (P < 0.001). The expression of miR-126 was 5.8 times higher in dogs with ICGN compared to GS, with no difference between MGN and MPGN (P = 1.00). Expression of urinary miR-21 (P = 0.71), miR-182 (P = 0.79), and miR-486 (P = 0.95) were not different between azotemic and non-azotemic dogs.< br>< br>Conclusions and clinical importance: MiR-126 could help identify dogs that could benefit from immunosuppressive therapy in the absence of a biopsy.