HP06 - Quantification of MicroRNAs 1275, 222, and 21 in Serum from Dogs with Chronic Hepatitis

Abstract: Background: MicroRNAs 1275, 222, and 21 are involved in copper homeostasis and their serum expression has been reported to be altered in human patients with Wilson’s disease.

Objective: To quantify microRNAs 1275, 222, and 21 in serum from dogs with copper-associated chronic hepatitis (CuCH), dogs with idiopathic chronic hepatitis (iCH), and healthy control dogs.

Animals: Stored serum samples from 8 dogs with histologically confirmed CuCH, 8 dogs with histologically confirmed iCH, and 8 healthy control dogs.

Methods: Retrospective cross-sectional study. Target MicroRNAs were quantified by real-time, reverse transcription polymerase chain reaction (RT-qPCR). MicroRNA 26b was used as housekeeping gene. Relative quantification was calculated using the ΔΔCt method. Kruskal-Wallis tests were used to compare differences in copy numbers between groups. Statistical significance was set at P < .05.

Results: Dogs with CuCH showed a decreased expression of MicroRNA 1275 compared to healthy controls (CuCH [median; range]: 0.15; 0.0 – 0.40; healthy controls: 1.7; 0.10 – 10.3) but this difference did not reach statistical significance (P = .06; Figure 1). Other post-hoc comparisons between groups were not significant (P = .13). No significant differences between groups were observed for MicroRNA 222 (P = .10) or 21 (P = .15), respectively.

Conclusions and clinical importance: These results, from a small number of dogs, do not support the diagnostic utility of microRNA 222 or 21 for the diagnosis of CuCH in dogs. However, larger cohort studies evaluating the utility of MicroRNA 1275 are warranted to determine the diagnostic utility of MicroRNA 1275.