The Correlation Between MicroRNAs in Serum and the Extent of Liver Injury

Objective To investigate the correlation between the absolute quantification of the microRNAs (miR-122, miR-451, miR-92a, miR-192) in serum during acute liver injury and the extent of liver injury on rat models of CCl₄ induced acute liver injury and mice models of acetaminophen (APAP) induced acute liver injury. Furthermore, to investigate the correlation between the absolute quantification of microRNAs in serum and the drug induced liver injury pathological scoring system (DILI-PSS). Methods The acute liver injury model in rat by CCl₄ (1.5 mL/kg), and the acute liver injury model in mice by APAP (160 mg/kg) were established. The serum at different time points on both models were collected respectively. The absolute quantification of microRNAs in serum were detected by using MiRbay^TM SV miRNA Assay kit. Meanwhile, the pathological sections of liver tissue of the mice at each time point were collected to analyze the correlation between microRNAs and the degree of liver injury. Results In CCl₄-induced rat acute liver injury model and APAP induced mouse acute liver injury, miR-122 and miR-192 appeared to be rising significantly, which remained the highest level at 24 h after treatment, and declined to the normal level after 72 h. In CCl₄-induced rat acute liver injury model, the change of miR-92a was fluctuated and had no apparent rules, miR-451 declined gradually, but not obviously. In mice acute liver injury model induced by APAP, miR-92a and miR-451 in the progress of liver injury declined gradually, reached the lowest point at 48 h, and then recovered. The result of correlation analysis indicated that miR-122 and miR-192 presented a good positive correlation with the DILI-PSS ( r=0.741 3，P<0.05; r=0.788 3, P<0.01). Conclusion The absolute quantification of miR-122 and miR-192 in serum has the highest level in 24 h, then decrease in 72 h, in both drug-induced and chemical liver injury. In addition, both the two microRNAs have good correlation with DILI-PSS in APAP-induced liver injury models.