Nonalcoholic fibrosing steatohepatitis is a uniform process throughout nonalcoholic fatty liver disease (NAFLD). MicroRNAs (miRNAs) have been suggested to modulate cellular processes in liver diseases. However, the functional role of miRNAs in nonalcoholic fibrosing steatohepatitis is largely unclear. In this study, we systematically analyzed the hepatic miRNAs by microarray analysis in nonalcoholic fibrosing steatohepatitis in C57BL/6J mice induced by methionine-choline deficient (MCD) diet. We identified 19 up-regulated and 18 down-regulated miRNAs in liver with fibrosis. Among these dysregulated miRNAs, miR-146a-5p was the most significant down-regulated miRNA. Luciferase activity assay confirmed that Wnt1 and Wnt5a were both the target genes of miR-146a-5p. Hepatic miR-146a-5p was down-regulated in fibrosing steatohepatitis, but its target genes Wnt1 and Wnt5a and their consequent effectors α-SMA and Col-1 were significantly up-regulated. In addition, miR-146a-5p was downregulated, whilst Wnt1 and Wnt5a were up-regulated in the activated primary hepatic stellate cells (HSCs) compared to the quiescent primary HSCs. Overexpression of miR-146a-5p in HSCs inhibited HSC activation and proliferation, which concomitant with the decreased expressions of Wnt1, Wnt5a, α-SMA and Col-1. In conclusion, miR-146a-5p suppresses activation and proliferation of HSCs in the progress of nonalcoholic fibrosing steatohepatitis through targeting Wnt1 and Wnt5a and consequent effectors α-SMA and Col-1.

Nonalcoholic fibrosing steatohepatitis is a uniform process that occurs throughout nonalcoholic fatty liver disease (NAFLD). MicroRNAs (miRNAs) have been shown to be involved in the biological processes, but the role and molecular mechanism of miRNAs in NAFLD are not entirely clear. In this study, we observed a significant reduction in the expression of miR-130a-3p in livers of a mouse model with fibrosis induced by a methionine–choline-deficient diet, of NAFLD patients, and in activated hepatic stellate cells (HSCs). A dual-luciferase activity assay confirmed that transforming growth factor-beta receptors (TGFBRs) 1 and 2 were both the target genes of miR-130a-3p. The hepatic expression of TGFBR1 and TGFBR2 was significantly increased. Moreover, the overexpression of miR-130a-3p in HSCs inhibited HSC activation and proliferation, concomitant with the decreased expression of TGFBR1, TGFBR2, Smad2, Smad3, matrix metalloproteinase-2 (MMP-2), MMP-9, type I collagen (Col-1), and Col-4. In addition, the overexpression of miR-130a-3p promoted HSC apoptosis by inducing the expression of caspase-dependent apoptosis genes. Transfection with si-TGFBR1 and si-TGFBR2 revealed effects on HSC function that were consistent with those of miR-130a-3p. TGFBR1 and TGFBR2 rescued the miR-130a-3p-mediated reductions in the mRNA and protein expression levels of Smad2, Smad3, Col-1, and Col-4. In conclusion, our findings suggest that miR-130a-3p might play a critical role in negatively regulating HSC activation and proliferation in the progression of nonalcoholic fibrosing steatohepatitis by directly targeting TGFBR1 and TGFBR2 via the TGF-β/SMAD signaling pathway.

ObjectiveTo evaluate whether gamma-glutamyl transpeptidase to platelet ratio index (GPRI) can diagnose the extent of liver fibrosis in Chinese patients with chronic hepatitis B (CHB) infection.MethodsThis prospective observational study used liver biopsy results as the gold standard to evaluate the ability of GPRI to predict hepatic fibrosis compared with two other markers, the aspartate aminotransferase (AST) to platelet ratio index (APRI) and fibrosis-4 score (FIB-4). The clinical and demographic factors that affected GPRI, independent of liver fibrosis, were assessed using multivariate linear regression analyses.ResultsThis study enrolled 312 patients with CHB. GPRI had a significantly positive correlation with liver fibrosis stage and the correlation coefficient was higher than that for APRI and FIB-4. The areas under the receiver operating curves for GPRI for significant fibrosis, bridging fibrosis, and cirrhosis were 0.728, 0.836, and 0.842, respectively. Of the three indices, GPRI had the highest diagnostic accuracy for bridging fibrosis and cirrhosis. Age, elevated AST and elevated total bilirubin levels were independent determinants of increased GPRI.ConclusionGPRI was a more reliable laboratory marker than APRI and FIB-4 for predicting the stage of liver fibrosis in Chinese patients with CHB.

MicroRNA (miRNA) play a pivotal role in the development of liver fibrosis. However, the functions of miRNA in hepatitis C virus (HCV)‐related liver fibrosis remain unclear. In this study, we systematically analyzed the microarray data of the serum miRNA in patients with HCV‐induced hepatic fibrosis. Among 41 dysregulated miRNA, miR‐1273g‐3p was the most significantly upregulated miRNA and correlated with the stage of liver fibrosis. Overexpression of miR‐1273g‐3p could inhibit translation of PTEN, increase the expression of α‐SMA, Col1A1, and reduce apoptosis in HSCs. Hence, we conclude that miR‐1273g‐3p might affect the activation and apoptosis of HSCs by directly targeting PTEN in HCV‐related liver fibrosis.

Interleukin-23 (IL-23) and its downstream factor IL-17 are the key cytokines involved in immune and inflammatory response in chronic liver diseases. This study aimed to investigate the role and molecular mechanisms of the IL-23/Th17 axis in chronic hepatitis C virus (HCV) infection, and the efficacy of IL-23/Th17 modulation in response to anti-HCV therapy. Sixty-six HCV-infected patients and 20 healthy controls were enrolled. The patients received PegIFNa-2a and ribavirin therapy for at least 48 weeks. The plasma level of IL-23 and the number of IL-17A-, IFN-γ-, and IL-21-producing peripheral blood mononuclear cells (PBMCs) at baseline and 12, 24, and 48 weeks following treatment were determined. The mRNA level of Th17 immune-associated molecules in PBMCs was evaluated by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) following treatment with IL-23 agonist or antagonist. Our data showed that, compared to healthy controls, HCV-infected patients had an increased plasma level of IL-23 and increased frequencies of IL-17A- and IFN-γ-producing PBMCs, whereas the HCV patients exhibited a reduced number of IL-21-producing PBMCs. However, the baseline frequencies of IL-21-producing PBMCs were markedly higher in HCV patients who achieved rapid virological response (RVR) than those without RVR. Additionally, the mRNA expressions of IL-21, IFN-γ, myxovirus resistance protein A (MxA), and suppressor of cytokine signaling 3 (SOCS3) were significantly upregulated in PBMCs, while FoxP3 expression was suppressed by IL-23 agonist. Thus, the IL-23/Th17 axis plays an important role in development of chronic HCV infection and antiviral response. IL-23 may enhance the antiviral activity of interferon-based therapy by modulating the expression of Th17 cells-associated molecules in HCV-infected patients.

In clinical practice, we found that microRNA (miR)-146a-5p is significantly up-regulated in peripheral blood mononuclear cells (PBMCs) of primary sjögren's syndrome (pSS) patients. In vitro experiments confirmed that miR-146a-5p promotes T helper 17 (Th17) cell differentiation, but the specific mechanism is still unknown. To solve this problem, 20 pSS patients and 20 healthy subjects were enrolled in this study and PBMCs were isolated from their blood. The expression of the membrane IL-23 R (mIL-23 R) in PBMCs was determined. CD3 + T cells were also isolated and used to further analyze the relationship between the ectodomain shedding of mIL-23 R and a disintegrin and metalloprotease 17 (ADAM17). Finally, miR-146a-5p inhibitor and mimics were transfected into PBMCs to evaluate the relationship between ADAM17 and mIL-23 R, and explore the role of mIL-23 R and ADAM17 in Th17 cell differentiation. Our results revealed a significantly increased expression of miR-146a-5p in PBMCs from pSS patients and significantly increased percentage of Th17 cells compared to PBMCs from healthy controls. Under polarization culture conditions, pSS patient-derived PBMCs can more easily differentiate into Th17 cells, which was, to a great extent, attributable to the increased expression of mIL-23 R. Moreover, ADAM17, an ectodomain sheddase of mIL-23 R, was targeted and negatively regulated by miR-146a-5p, which reduced the ectodomain shedding of mIL-23 R. Overall, our results suggested that miR-146a-5p could promote Th17 cell differentiation through targeting and negatively regulating ADAM17. Thus, these results might offer a new approach in the treatment of pSS.

Abstract. Mounting evidence indicates that dysregulated microRNAs (miRNAs) are important in the etiology and pathogenesis of steatohepatitis. However, the functions of miRNAs in the pathophysiological process of non-alcoholic steatohepatitis (NASH) are poorly understood. In this study, C57BL/6J mice were fed a methionine-choline-deficient (MCD) diet for eight weeks in order to induce hepatic steatohepatitis. Using reverse transcription polymerase chain reaction, the hepatic expression levels of miR-199a-5p, miR-122 and miR-221 in the mice were examined. Bioinformatic analysis of dysregulated miR-199a-5p was performed to predict the potential role of miR-199a-5p in NASH. The MCD diet was found to significantly reduce miR-122 expression levels and significantly increase miR-199a-5p expression levels in mouse livers, compared with those of mice fed a control diet. In the bioinformatic analysis, miR-199a-5p was identified to be predominantly involved in transcription, protein serine/threonine kinase activity, insulin signaling, and the Wnt and mitogen-activated protein kinase signaling pathways. The regulation of nuclear receptor corepressor 1 (NCOR1) by miR-199a-5p was also examined by silencing and overexpressing this miRNA in LX-2 cells. The data revealed that NCOR1 protein levels were significantly reduced and enhanced by miR-199a-5p mimic and inhibitor, respectively. These findings suggest a key role for miR-199a-5p in the progression of NASH through inhibition of NCOR1 translation, and provide novel insights into NASH pathogenesis.

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