Establishment of an experimental method for detecting circulating miRNAs in BDL mice

Despite its great potency in self-rehabilitation, liver is the most vulnerable organ, and an early minor liver injury is unfortunately undetectable by the traditional assay of aminotransferases; hence, more sensitive and specific biomarkers of minor liver injury have attracted much attention. A number of studies have suggested that circulating microRNAs (miRNAs) are accessible and attractive parameters of early tissue injury. A recent study has found that plasma microRNA-122 is a disease severity-dependent biomarker, and there is an elevated level of microRNA-122 prior to the alteration of aminotransferases in viral, alcohol, and chemical-related hepatic injuries. Since bile duct-ligated (BDL) mice have been well adapted as an effective model of cholestatic hepatic injury, liver fibrosis, liver cirrhosis, and their relevant complications, we hypothesized that detection of circulating miRNAs will probably find its unique utility in BDL model and thus exploited an effective and reliable experimental method of studying serum-based miRNAs in BDL mice.