Depletion of Tgfbr2 in hepatocytes alleviates liver fibrosis and restores hepatic function in fibrotic mice.

OBJECTIVES: Previous studies have demonstrated the pivotal role of transforming growth factor (TGF)-ß signaling in activating hepatic stellate cells during liver fibrosis. In this study we aimed to demonstrate the effects and underlying mechanism of TGF-ß signaling in hepatocytes on hepatic fibrogenesis. METHODS: Hepatocyte-specific Tgfbr2-knockout (Tgfbr2HKO ) mice were generated by AAV8-TBG-Cre injection via the tail vein of Tgfbr2f/f mice. CCl4 was injected intraperitoneally twice a week for 4 weeks to establish the fibrotic mouse model. The expression of the fibrogenesis markers was evaluated by immunohistochemistry, western blot, and real-time polymerase chain reaction (PCR). RNA-seq analysis was used to detect the transcriptional profiles of primary hepatocytes isolated from Tgfbr2HKO mice and control mice. RESULTS: The expression of TßR2 (Tgfbr2) was markedly upregulated in hepatocytes of the fibrotic liver. Tgfbr2 depletion in hepatocytes decreased the expressions of profibrogenic markers (Col1a1 and Acta2) in the CCl4 -treated fibrotic liver. RNA-seq analysis revealed that Tgfbr2 deletion in hepatocytes significantly reduced the inflammatory response and suppressed epithelial-mesenchymal transition of hepatocytes accompanied by upregulation of the metabolic pathways during liver fibrosis. Moreover, the expressions of hepatocyte nuclear factors (HNFs), including Hnf4α, Foxa1, Foxa2, and Foxa3, which are important for maintaining liver metabolism and homeostasis, were decreased in fibrotic livers and significantly increased after Tgfbr2 blockade. CONCLUSION: Blocking the TGF-ß signaling pathway in hepatocytes reduces hepatic fibrosis and improves hepatic function in fibrotic livers.

Zymolytic grain extract facilitates the conversion of liver tumor cells to hepatocyte-like cells through hepatocyte nuclear factors.

At present, malignant tumors are an urgent global threat to human health. Conversion of cancer cells to normal-like or normal cells will open new therapeutic avenues for eradicating cancer. It has been reported that compounds extracted from grains display biological activities, such as antioxidant, antiviral and antitumor activities. In this study, we identified clear changes in a liver tumor cell line (HepG2) after stimulation with zymolytic grain extract (ZGE) supernatants. The expression levels of hepatocyte nuclear factor 1A (HNF1A), hepatocyte nuclear factor 4A (HNF4A) and forkhead box protein A3 (FOXA3) were significantly increased. Eukaryotic transcriptome analyses revealed that trends in the transcriptional changes for genes were similar in HepG2 cells stimulated with ZGE (zHeps) and the normal hepatocyte cell line L02. Changes in the expression levels of genes involved in drug transport, metabolism and the malignant characteristics of cancer cells in nude mice further indicated that ZGE regulated the expression of HNF1A, HNF4A and FOXA3, which altered the expression of a series of hepatocyte-specific genes. It was also confirmed that zHeps acquired some of the characteristics of hepatocyte-like cells. Our results not only provide new ideas for the treatment of liver tumors but also lay a solid foundation for the application of combination therapy.

Proteomic Investigations of Transcription Factors Critical in Geniposide-Mediated Suppression of Alcoholic Steatosis and in Overdose-Induced Hepatotoxicity on Liver in Rats.

Alcoholic steatosis is one of the most prevalent forms of liver disease, and appropriate insight and application of anti-steatosis drugs must be considered. Geniposide, the major active constituent of the Gardenia jasminoides (Ellis) fruit, has been commonly used as a traditional herbal medicine for the treatment of liver diseases. However, its hepatoprotective effect on alcoholic steatosis has not been reported. Moreover, geniposide overdose-induced hepatotoxicity was demonstrated. Hence, its therapeutic effects and overdose-induced hepatotoxicity in rat models along with corresponding targets, especially the targets of transcription factors (TFs), were systematically investigated in this study by using a concatenated tandem array of consensus TF response elements. The results indicate that geniposide can attenuate alcoholic steatosis and liver injury by enhancing the transcriptional activities of peroxisome proliferator-activated receptor-α and hepatocyte nuclear factors 1α and 4α, while geniposide overdose perturbs other TFs. In addition, therapeutic doses and overdoses of geniposide have differentiated target TFs. This study is the first to provide a systematic insight into the difference of critical transcription factors between the actions of therapeutic doses and overdoses of geniposide, as well as much-needed attention to the important topic of alcoholic liver disease therapy.

Baicalin benefits the anti-HBV therapy via inhibiting HBV viral RNAs.

BACKGROUND: Although current antiviral treatments (nucleoside analogs, NAs) for chronic hepatitis B virus (HBV) infection are effective in suppressing HBV-DNA replication, their clinical outcomes can be compromised by the increasing drug resistance and the inefficiency in promoting HBsAg/HBeAg seroconversion. OBJECTIVES: In this study, we will explore possible effects and mechanism of a natural product baicalin (BA) with the anti-HBV efficacy of entecavir (ETV), a first-line anti-HBV drug, in HBV-DNA, HBsAg/HBeAg seroconversion and drug-resistance. METHODS: The co-effects of BA and ETV were conducted in wild-type/NA-resistance mutant HBV cell lines and DHBV-infected duckling models. HBV-DNA/RNAs, HBsAg/HBeAg, host factors (hepatocyte nuclear factors) were explored for possible anti-HBV mechanism. RESULTS AND DISCUSSION: BA could significantly enhance and reduced HBsAg and HBeAg in hepG2.2.15, a wild-type HBV cell line. Co-treatment of BA and ETV had a more dramatic effect in NA-resistant HBVrtM204V/rtLl80M transfected hepG2 cells. Our study further revealed that BA mainly inhibited the production of HBV RNAs (3.5, 2.4, 2.1kb), the templates for viral proteins and HBV-DNA synthesis. BA blocked HBV RNAs transcription possibly by down-regulating transcription and expression of HBV replication dependent hepatocyte nuclear factors (HNF1α and HNF4α). Thus, BA may benefit the anti-HBV therapy via inhibiting HBV viral RNAs.

Impact of Nucleotide Mutations at the HNF3- and HNF4-Binding Sites in Enhancer 1 on Viral Replication in Patients with Chronic Hepatitis B Virus Infection.

BACKGROUND/AIMS: The hepatitis B virus (HBV) genome contains binding sites for hepatocyte nuclear factors (HNF) 3 and 4 in the core domain of enhancer 1 (Enh1), and mutations in this domain have a strong impact on virus replication. We aimed to identify frequent base-mutation sites in the core domain of Enh1 and to examine the impact of these mutations on viral replication. METHODS: We studied virological characteristics and genetic sequences in 387 patients with chronic hepatitis B. We evaluated functional differences associated with specific mutations within the core domain of Enh1. RESULTS: Mutations in the core domain were found with significant frequency in C1126 (122/387 [31.5%], the binding site for HNF3) and in C1134 (106/387 [27.4%], the binding site for HNF4). A single mutation at nt 1126 (C1126) was identified in 17/123 (13.8%), and 105/123 (85.4%) had double mutations (C1126/1134). The level of HBV DNA (log10 copies/mL) was lower in single mutants (C1126, 5.81±1.25) than in wild (6.80±1.65) and double mutants (C1126/1134, 6.81±1.54). Similarly, the relative luciferase activity of C1126 and C1126/C1134 was 0.18 and 1.12 times that of the wild-type virus, respectively. CONCLUSIONS: Mutations in the HNF3 binding site inhibit viral replication, whereas mutations at the HNF4 binding site restore viral replication.

Dual Role of miR-122 in Molecular Pathogenesis of Viral Hepatitis.

The hepatic microRNA (miRNA), miR-122, is the most abundant miRNA within the liver, where it accounts for 70% of the total miRNA pool. It is known that miR-122, as an unusual host factor, increases the abundance of hepatitis C virus (HCV) RNA in HCV infection by binding directly to the 5'-UTR of the viral genome. Therefore, it has been suggested as a potential target for the treatment of hepatitis C. However, recent evidence shows that miR-122 decreases HBV replication through the inhibitory effect of p53 on HBV transcription, and consequently it acts as a tumor-suppressor through both a decrease in HBV replication and by directly targeting cyclin G1, as well as Wnt/beta-catenin, and NDRG3 pathways. This paper will briefly discuss the underlying mechanisms for the dual role of miR-122 in viral hepatitis, and explains why therapeutic applications of miR-122 may differ based on the underlying disease.