Absolute quantification of serum microRNA-122 and its correlation with liver inflammation grade and serum alanine aminotransferase in chronic hepatitis C patients

Abstract

Objectives: MicroRNA-122 has been shown to be crucial for efficient HCV RNA replication in vitro. Pretreatment intrahepatic microRNA-122 levels in chronic hepatitis C (CHC) patients have been associated with the outcomes of interferon therapy. Here, we determined microRNA-122 serum levels in CHC patients and healthy donors using an absolute quantification approach and evaluated the correlation with liver inflammation grades and serum alanine aminotransferase (ALT) levels. Methods: Serum samples were collected from 105 treatment-naive CHC patients, 11 acute hepatitis patients, and 33 healthy donors. Serum microRNA-122 was measured using the TaqMan RT-qPCR. The cycle threshold values were converted to copy numbers by drawing a standard curve using a chemical synthetic standard. For accurate quantification, copy numbers were further normalized according to the recovery ratios of spiked-in cel-miR-39. Results: Serum levels of microRNA-122 were significantly higher in acute hepatitis and CHC patients than in healthy donors (p < 0.001). However, there was no significant association between microRNA-122 and ALT serum levels or liver inflammation grades. Conclusions: The present study showed that serum microRNA-122 was elevated in acute and chronic hepatitis patients. However, this biomarker for acute liver injury did not reflect the liver inflammation activity in CHC patients.

Keywords

• MicroRNA-122
• Chronic hepatitis C
• ALT
• Liver inflammation