OBJECTIVES: The liver contains large amounts of microRNA-122 (miR-122), whereas other tissues contain only marginal amounts of this miRNA. MicroRNAs have also been found to circulate in the blood in a cell free form; their potential as readily accessible disease markers is currently evaluated. Here we investigated if the serum levels of miR-122 might be useful as disease parameter in patients with chronic hepatitis C virus (HCV) infection.METHODS: RNA was extracted from sera of patients with chronic HCV infection and healthy controls and was analyzed for miR-122 content by quantitative real-time reversetranscription PCR and for standard parameters of liver function. Liver biopsies from the same patients were examined for the histologic activity index (HAI) and the degree of fibrosis.RESULTS: Sera from patients with chronic HCV infection contained higher levels of miR-122 than sera from healthy controls. Serum miR-122 levels correlated well with markers of liver inflammatory activity, i. e. serum levels of alanine leucine transaminase (ALT) and aspartate transaminase, and the HAI score. In patients with persistently normal ALT levels, serum miR-122 levels did not differ from healthy controls. There was no correlation of serum miR-122 levels with serum albumin, international normalized ratio, liver fibrosis or serum HCV RNA.CONCLUSIONS: The serum level of miR-122 strongly correlates with serum ALT activity and with necroinflammatory activity in patients with chronic HCV infection and elevated ALT levels, but not with fibrosis stage and functional capacity of the liver.

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BackgroundMicroRNAs circulating in the blood, stabilized by complexation with proteins and/or additionally by encapsulation in lipid vesicles, are currently being evaluated as biomarkers. The consequences of their differential association with lipids/vesicles for their stability and use as biomarkers are largely unexplored and are subject of the present study.MethodsThe levels of a set of selected microRNAs were determined by quantitative reverse-transcription PCR after extraction from sera or vesicle- and non-vesicle fractions prepared from sera. The stability of these microRNAs after incubation with RNase A or RNase inhibitor, an inhibitor of RNase A family enzymes was studied.ResultsThe levels of microRNA-1 and microRNA-122, but not those of microRNA-16, microRNA-21 and microRNA-142-3p, declined significantly during a 5-h incubation of the sera. RNase inhibitor prevented the loss of microRNAs in serum as well as the degradation of microRNA-122, a microRNA not expressed in blood cells, in whole blood. Stabilization of microRNA-122 was also achieved by hemolysis. Prolonged incubation of the sera led to enrichment of vesicle-associated relative to non-vesicle-associated microRNAs. Vesicle-associated microRNAs were more resistant to RNase A treatment than the respective microRNAs not associated with vesicles.ConclusionsSerum microRNAs showed differential stability upon prolonged incubation. RNase inhibitor might be useful to robustly preserve the pattern of cell-free circulating microRNAs. In the case of microRNAs not expressed in blood cells this can also be achieved by hemolysis. Vesicle-associated microRNAs appeared to be more stable than those not associated with vesicles, which might be useful to disclose additional biomarker properties of miRNAs.

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SUMMARY BackgroundProton pump inhibitors (PPI) are widely used in patients with liver diseases. Within the last years, there have been concerns about the PPI use as they may promote infections in patients with cirrhosis.

Vitamin D is an important immune modulator that plays an emerging role in inflammatory and metabolic liver diseases, including infection with hepatitis C virus (HCV). In contrast, the relationship between vitamin D metabolism and chronic hepatitis B (CHB) is less well characterized. Therefore, we quantified 25(OH)D 3 serum levels in a cohort of 203 treatmentna€ ıve patients with chronic hepatitis B virus (HBV) infection and tested for their association with clinical parameters of CHB. Of 203 patients, 69 (34%), 95 (47%), and 39 (19%) had severe vitamin D deficiency (25(OH)D 3 <10 ng/mL), vitamin D insufficiency (25(OH)D 3 10 and <20 ng/mL), or adequate vitamin D serum levels (25(OH)D 3 20 ng/mL), respectively. In both uni-and multivariate analyses, HBV DNA viral load (log 10 IU/mL) was a strong predictor of low 25(OH)D 3 serum levels (P 5 0.0007 and P 5 0.000048, respectively) and vice versa. Mean 25(OH)D 3 serum concentrations in patients with HBV DNA <2,000 versus 2,000 IU/mL were 17 versus 11 ng/mL, respectively (P < 0.00001). In addition, hepatitis B early antigen (HBeAg)-positive patients had lower 25(OH)D 3 serum levels than HBeAg-negative patients (P 5 0.0013). Finally, 25(OH)D 3 and HBV DNA serum levels showed inverse seasonal fluctuations. Conclusion: Low 25(OH)D 3 serum levels are associated with high levels of HBV replication in patients with CHB. This represents a major difference from chronic hepatitis C, where numerous previous studies have shown a lack of correlation between HCV viral load and vitamin D serum levels. Inverse seasonal fluctuations of 25(OH)D 3 and HBV DNA serum levels are suggestive of a functional relationship between both variables. (HEPATOLOGY 2013;58:1270-1276

miR-122 is a liver-specific microRNA, which also circulates in the blood. The levels of miR-122 in serum and plasma correlate with hepatic necroinflammation in patients with hepatitis B virus (HBV) infection. Here, we investigated whether miR-122 levels correlate with surrogate markers for viral replication and translation. Furthermore, we examined whether miR-122 levels differ in the different groups of HBV-infected patients and whether miR-122 levels may be useful to identify patients with higher or lower risk for liver disease progression. Therefore, RNA was extracted from sera of therapy-naïve patients with HBV infection (n = 89) and from healthy volunteers (n = 19). The concentration of miR-122 was assessed by quantitative real-time reverse-transcription PCR. HBs antigen and HBV DNA levels were quantified as surrogate parameters for HBV replication and translation. Liver biopsies were examined according to the histological activity index and the degree of fibrosis was assessed. We found that the miR-122 serum concentration correlated with the level of ALT, HBV DNA and HBs antigen (r = 0.259, P < 0.05; r = 0.225, P < 0.05; r = 0.508, P < 0.001, respectively). The miR-122 serum levels discriminated the different patient groups infected with HBV from healthy subjects (P < 0.001), and inactive carrier patients with high (>3500 IU/mL) or low (<3500 IU/mL) levels of HBs antigen could be differentiated by the miR-122 serum concentration (P < 0.05). As serum miR-122 levels strongly correlated with HBs antigen, it might be an indicator for viral translation. Furthermore, serum miR-122 levels discriminated HBV carrier patients with high or low risk for disease progression and may, thus, be an additional marker for risk stratification.

BackgroundMicroRNA-21 (miR-21) is up-regulated in tumor tissue of patients with malignant diseases, including hepatocellular carcinoma (HCC). Elevated concentrations of miR-21 have also been found in sera or plasma from patients with malignancies, rendering it an interesting candidate as serum/plasma marker for malignancies. Here we correlated serum miR-21 levels with clinical parameters in patients with different stages of chronic hepatitis C virus infection (CHC) and CHC-associated HCC.Methodology/Principal Findings62 CHC patients, 29 patients with CHC and HCC and 19 healthy controls were prospectively enrolled. RNA was extracted from the sera and miR-21 as well as miR-16 levels were analyzed by quantitative real-time PCR; miR-21 levels (normalized by miR-16) were correlated with standard liver parameters, histological grading and staging of CHC. The data show that serum levels of miR-21 were elevated in patients with CHC compared to healthy controls (P<0.001); there was no difference between serum miR-21 in patients with CHC and CHC-associated HCC. Serum miR-21 levels correlated with histological activity index (HAI) in the liver (r = −0.494, P = 0.00002), alanine aminotransferase (ALT) (r = −0.309, P = 0.007), aspartate aminotransferase (r = −0.495, P = 0.000007), bilirubin (r = −0.362, P = 0.002), international normalized ratio (r = −0.338, P = 0.034) and γ-glutamyltransferase (r = −0.244, P = 0.034). Multivariate analysis revealed that ALT and miR-21 serum levels were independently associated with HAI. At a cut-off dCT of 1.96, miR-21 discriminated between minimal and mild-severe necroinflammation (AUC = 0.758) with a sensitivity of 53.3% and a specificity of 95.2%.Conclusions/SignificanceThe serum miR-21 level is a marker for necroinflammatory activity, but does not differ between patients with HCV and HCV-induced HCC.