Immunosuppression induces regression of fibrosis in primary biliary cholangitis with moderate-to-severe interface hepatitis.

BACKGROUND: In patients with primary biliary cholangitis (PBC) treated with ursodeoxycholic acid (UDCA), the presence of moderate-to-severe interface hepatitis is associated with a higher risk of liver transplantation and death. This highlights the need for novel treatment approaches. In this study, we aimed to investigate whether combination therapy of UDCA and immunosuppressant (IS) was more effective than UDCA monotherapy. METHODS: We conducted a multicenter study involving PBC patients with moderate-to-severe interface hepatitis who underwent paired liver biopsies. Firstly, we compared the efficacy of the combination therapy with UDCA monotherapy on improving biochemistry, histology, survival rates, and prognosis. Subsequently we investigated the predictors of a beneficial response. RESULTS: This retrospective cohort study with prospectively collected data was conducted in China from January 2009 to April 2023. Of the 198 enrolled patients, 32 underwent UDCA monotherapy, while 166 received combination therapy, consisting of UDCA combined with prednisolone, prednisolone plus mycophenolate mofetil (MMF), or prednisolone plus azathioprine (AZA). The monotherapy group was treated for a median duration of 37.6 months (IQR 27.5-58.1), and the combination therapy group had a median treatment duration of 39.3 months (IQR 34.5-48.8). The combination therapy showed a significantly greater efficacy in reducing fibrosis compared to UDCA monotherapy, with an 8.3-fold increase in the regression rate (from 6.3% to 52.4%, P < 0.001). Other parameters, including biochemistry, survival rates, and prognosis, supported its effectiveness. Baseline IgG >1.3 × ULN and ALP <2.4 × ULN were identified as predictors of regression following the combination therapy. A predictive score named FRS, combining these variables, accurately identified individuals achieving fibrosis regression with a cut-off point of ≥ -0.163. The predictive value was validated internally and externally. CONCLUSION: Combination therapy with IS improves outcomes in PBC patients with moderate-to-severe interface hepatitis compared to UDCA monotherapy. Baseline IgG and ALP are the most significant predictors of fibrosis regression. The new predictive score, FRS, incorporating baseline IgG and ALP, can effectively identify individuals who would benefit from the combination therapy.

Gamma-Muricholic Acid Inhibits Nonalcoholic Steatohepatitis: Abolishment of Steatosis-Dependent Peroxidative Impairment by FXR/SHP/LXRα/FASN Signaling.

Nonalcoholic steatohepatitis (NASH) reflects the outcome of steatosis-based peroxidative impairment. Here, the effect and mechanism of γ-muricholic acid (γ-MCA) on NASH were investigated on the basis of its actions in hepatic steatosis, lipid peroxidation, peroxidative injury, hepatocyte apoptosis, and its NAFLD activity score (NAS). The agonist action of γ-MCA on farnesoid X receptor (FXR) upregulated the small heterodimer partner (SHP) expression of hepatocytes. An increase in SHP attenuated the triglyceride-dominated hepatic steatosis which was induced in vivo by a high-fat high-cholesterol (HFHC) diet and in vitro by free fatty acids depending on the inhibition of liver X receptor α (LXRα) and fatty acid synthase (FASN). In contrast, FXR knockdown abrogated the γ-MCA-dependent lipogenic inactivation. When compared to their excessive production in HFHC diet-induced rodent NASH, products of lipid peroxidation (MDA and 4-HNE) exhibited significant reductions upon γ-MCA treatment. Moreover, the decreased levels of serum alanine aminotransferases and aspartate aminotransferases demonstrated an improvement in the peroxidative injury of hepatocytes. By TUNEL assay, injurious amelioration protected the γ-MCA-treated mice against hepatic apoptosis. The abolishment of apoptosis prevented lobular inflammation, which downregulated the incidence of NASH by lowering NAS. Collectively, γ-MCA inhibits steatosis-induced peroxidative injury to ameliorate NASH by targeting FXR/SHP/LXRα/FASN signaling.

Disability-adjusted life years and the trends of the burden of colorectal cancer: a population-based study in Shanghai, China during 2002 to 2016.

BACKGROUND: Colorectal cancer (CRC) still ranks the top in morbidity and mortality of cancers worldwide, posing a huge threat and burden to the society. We aimed to determine the age-standardized incidence, mortality, and disability-adjusted life years (DALYs) of CRC and explore potential changes in the temporal trends of the CRC burden in Shanghai during 2002 to 2016. METHODS: The cancer statistics and demographics were obtained from the Cancer Registry and the Statistics Bureau of Pudong New Area, respectively. Data from 2002 to 2016 were included and analyzed retrospectively. DALYs were calculated using DisMod and the age-standardized rates (ASRs) were obtained according to Segi world standard population. Joinpoint regression was used to measure the trends in CRC incidence and to estimate the annual percent change. RESULTS: The increasing trend of CRC ASR incidence halted after 2014, coinciding with the introduction of the Shanghai CRC screening program. The ASRs of mortality and DALYs increased, at 0.42% ( P  < 0.05) and 4.07% ( P  < 0.001) per year, respectively, which were mainly driven by men and individuals aged above the CRC screening program target. CONCLUSIONS: The disease burden of CRC in Shanghai remains serious, especially among men, and individuals aged >74 years. The benefits of the screening program have been partially proven by the ASRs of CRC incidence, providing important insights into better and wider application of screening programs.

Profile analysis and functional modeling identify circular RNAs in nonalcoholic fatty liver disease as regulators of hepatic lipid metabolism.

Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease, associated with an outcome of hepatic fibrosis/cirrhosis and hepatocellular carcinoma. However, limited exploration of the underlying mechanisms hinders its prevention and treatment. To investigate the mechanisms of epigenetic regulation in NAFLD, the expression profile of circular RNA (circRNA) of rodents in which NAFLD was induced by a high-fat, high-cholesterol (HFHC) diet was studied. Modeling of the circRNA-microRNA (miRNA) -mRNA regulatory network revealed the functional characteristics of NAFLD-specific circRNAs. The targets and effects in the liver of such NAFLD-specific circRNAs were further assessed. Our results uncovered that the downregulation of 28 annotated circRNAs characterizes HFHC diet-induced NAFLD. Among the downregulated circRNAs, long intergenic non-protein coding RNA, P53 induced transcript (LNCPINT) -derived circRNAs (circ_0001452, circ_0001453, and circ_0001454) targeted both miR-466i-3p and miR-669c-3p. Their deficiency in NAFLD abrogated the circRNA-based inhibitory effect on both miRNAs, which further inactivated the AMPK signaling pathway via AMPK-α1 suppression. Inhibition of the AMPK signaling pathway promotes hepatic steatosis, depending on the transcriptional and translational upregulation of lipogenic genes, such as those encoding sterol regulatory element-binding protein 1 (SREBP1) and fatty acid synthase (FASN) in hepatocytes. The levels of LNCPINT-derived circRNAs displayed a negative association with hepatic triglyceride (TG) concentration. These findings suggest that loss of LNCPINT-derived circRNAs may underlie NAFLD via miR-466i-3p- and miR-669c-3p-dependent inactivation of the AMPK signaling pathway.

Regulation of PPAR-γ activity in lipid-laden hepatocytes affects macrophage polarization and inflammation in nonalcoholic fatty liver disease.

BACKGROUND: Lipid metabolism disorder and inflammatory-immune activation are vital triggers in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Various studies have shown that PPAR-γ exerts potent anti-inflammatory and immunomodulatory properties. However, little is known about the regulation of PPAR-γ activity in modulating cell crosstalk in NAFLD. AIM: To investigate whether the regulation of PPAR-γ activity in lipid-laden hepatocytes affects macrophage polarization and inflammation. METHODS: Primary hepatocytes were isolated from wild-type C57BL6/J mice or hepatocyte-specific PPAR-γ knockout mice and incubated with free fatty acids (FFAs). Macrophages were incubated with conditioned medium (CM) from lipid-laden hepatocytes with or without a PPAR-γ agonist. Wild-type C57BL/6J mice were fed a high-fat (HF) diet and administered rosiglitazone. RESULTS: Primary hepatocytes exhibited significant lipid deposition and increased ROS production after incubation with FFAs. CM from lipid-laden hepatocytes promoted macrophage polarization to the M1 type and activation of the TLR4/NF-κB pathway. A PPAR-γ agonist ameliorated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes and subsequently prevented M1 macrophage polarization. Hepatocyte-specific PPAR-γ deficiency aggravated oxidative stress and NLRP3 inflammasome activation in lipid-laden hepatocytes, which further promoted M1 macrophage polarization. Rosiglitazone administration improved oxidative stress and NLRP3 inflammasome activation in HF diet-induced NAFLD mice in vivo. CONCLUSION: Upregulation of PPAR-γ activity in hepatocytes alleviated NAFLD by modulating the crosstalk between hepatocytes and macrophages via the reactive oxygen species-NLRP3-IL-1ß pathway.

lncRNA NONRATT013819.2 promotes transforming growth factor-ß1-induced myofibroblastic transition of hepatic stellate cells by miR24-3p/lox.

Long noncoding RNAs (lncRNAs) are key regulators of hepatic stellate cells (HSCs), yet the role of upregulated lncRNA-NONRATT013819.2 in activated HSCs remains uncertain. In this study, the effects of NONRATT013819.2 on proliferation, apoptosis, migration, and contraction of transforming growth factor (TGF)-ß1-induced HSCs were investigated. The mechanisms of NONRATT013819.2 on the activated HSCs were explored by loss-of-function of NONRATT013819.2 and gain-of-function of the target gene. Here, TGF-ß1 treatment resulted in a gradual increase in the expression of cytoskeleton markers (collagen, α-SMA, and TIMP1), NONRATT013819.2, miR24-3p, and lysyl oxidase (Lox) over time in HSCs. NONRATT013819.2 acted as a sponge of miR24-3p to competitively abolish the inhibition of the lox gene in HSCs. Silencing of NONRATT013819.2 suppressed the expression of cytoskeleton markers, proliferation, and the proportion of cells that entered the S-phase, and promoted apoptosis in TGF-ß1-activated HSCs. These effects were reversed when lox overexpression was introduced simultaneously. Similarly, silencing of NONRATT013819.2 also blocked ECM reconstruction, while recused by lox overexpression in TGF-ß1-activated HSCs. In conclusion, upregulation of NONRATT013819.2 promotes the myofibroblastic transition by competitively binding miR24-3p to release lox in HSCs. Therefore, targeted therapy of NONRATT013819.2 may have the potential for liver fibrosis.

Morphological, Functional, and Tissue Characterization of Silent Myocardial Involvement in Patients With Primary Biliary Cholangitis.

BACKGROUND & AIMS: Cirrhotic cardiomyopathy is a major complication and cause of morbidity in end-stage primary biliary cholangitis (PBC). However, it is unclear whether there is clinically silent myocardial involvement at the early stage of PBC before cirrhosis and cardiac manifestations. This prospective, three-center, multi-modality cardiac imaging study on the early identification of myocardial impairment in PBC (EARLY-MYO-PBC) was designed to identify silent myocardial impairment in PBC patients without cardiac manifestations. METHODS: A total of 112 subjects (56 with PBC and 56 age- and sex-matched controls) undergoing cardiovascular magnetic resonance (CMR) were enrolled. Demographic, serologic, and cardiac imaging data were prospectively collected. All participants had no cardiac discomfort or previous heart disease and had normal electrocardiographic findings. RESULTS: Subclinical myocardial involvement, as evidenced by cardiac morphologic, functional, and tissue characterization changes on CMR, including hyperdynamic left ventricular (LV) ejection fraction (median, 75% in PBC patients vs 69% in controls, P = .029), subclinical myocardial edema by T2-short tau inversion recovery (21% vs 2% in controls, P = .001), elevated extracellular matrix indices (30% vs 26% in controls, P < .001), and impaired myocardial viability by positive late gadolinium enhancement (LGE) (36%), was detected in PBC patients. Importantly, a mid-wall "stripe" at the LV septum was identified as a PBC-specific LGE pattern that differs from other known cardiomyopathies. In multivariate analysis, gp210 positivity (odds ratio [OR] = 9.909, P = .010), lower hemoglobin (OR = 0.919, P = .004), and body mass index (OR = 0.638, P = .005) were independent predictors of cardiac abnormalities in PBC. CONCLUSIONS: This study demonstrates clinically silent cardiac impairment with specific CMR patterns in PBC, allowing optimal screening for early myocardial impairment and potentially timely therapies. (Trial registration no.: NCT03545672).

Evaluation of controlled attenuation parameter in assessing hepatic steatosis in patients with autoimmune liver diseases.

BACKGROUND: Hepatic steatosis commonly occurs in some chronic liver diseases and may affect disease progression. AIM: To investigate the performance of controlled attenuation parameter (CAP) for the diagnosis of hepatic steatosis in patients with autoimmune liver diseases (AILDs). METHODS: Patients who were suspected of having AILDs and underwent liver biopsy were consistently enrolled. Liver stiffness measurement (LSM) and CAP were performed by transient elastography. The area under the receiver operating characteristic (AUROC) curve was used to evaluate the performance of CAP for diagnosing hepatic steatosis compared with biopsy. RESULTS: Among 190 patients with biopsy-proven hepatic steatosis, 69 were diagnosed with autoimmune hepatitis (AIH), 18 with primary biliary cholangitis (PBC), and 27 with AIH-PBC overlap syndrome. The AUROCs of CAP for the diagnosis of steatosis in AILDS were 0.878 (0.791-0.965) for S1, 0.764 (0.676-0.853) for S2, and 0.821 (0.716-0.926) for S3. The CAP value was significantly related to hepatic steatosis grade (P < 0.001). Among 69 patients with AIH, the median CAP score was 205.63 ± 47.36 dB/m for S0, 258.41 ± 42.83 dB/m for S1, 293.00 ± 37.18 dB/m for S2, and 313.60 ± 27.89 dB/m for S3. Compared with patients with nonalcoholic fatty liver disease (NAFLD) presenting with autoimmune markers, patients with AIH concomitant with NAFLD were much older and had higher serum IgG levels and LSM values. CONCLUSION: CAP can be used as a noninvasive diagnostic method to evaluate hepatic steatosis in patients with AILDs. Determination of LSM combined with CAP may help to identify patients with AIH concomitant with NAFLD from those with NAFLD with autoimmune phenomena.

miR-16 integrates signal pathways in myofibroblasts: determinant of cell fate necessary for fibrosis resolution.

Liver fibrosis is characterized by the transdifferentiation of hepatic stellate cells (HSCs) to myofibroblasts and poor response to treatment. This can be attributed to the myofibroblast-specific resistance to phenotype reversal. In this study, we complemented miR-16 into miR-16-deficient myofibroblasts and analyzed the global role of miR-16 using transcriptome profiling and generating a pathway-based action model underlying transcriptomic regulation. Phenotypic analysis of myofibroblasts and fibrogenic characterization were used to understand the effect of miR-16 on phenotypic remodeling of myofibroblasts. miR-16 expression altered the transcriptome of myofibroblasts to resemble that of HSCs. Simultaneous targeting of Smad2 and Wnt3a, etc. by miR-16 integrated signaling pathways of TGF-ß and Wnt, etc., which underlay the comprehensive regulation of transcriptome. The synergistic effect of miR-16 on the signaling pathways abolished the phenotypic characteristics of myofibroblasts, including collagen production and inhibition of adipogenesis. In vivo, myofibroblast-specific expression of miR-16 not only eliminated mesenchymal cells with myofibroblast characteristics but also restored the phenotype of HSCs in perisinusoidal space. This phenotypic remodeling resolved liver fibrosis induced by chronic wound healing. Therefore, miR-16 may integrate signaling pathways crucial for the fate determination of myofibroblasts. Its global effect induces the reversal of HSC-to-myofibroblast transdifferentiation and, subsequently, the resolution of fibrogenesis. Taken together, these findings highlight the potential of miR-16 as a promising therapeutic target for liver fibrosis.

Performance of transient elastography in assessing liver fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis overlap syndrome.

AIM: To investigate the performance of transient elastography (TE) for diagnosis of fibrosis in patients with autoimmune hepatitis-primary biliary cholangitis (AIH-PBC) overlap syndrome. METHODS: A total of 70 patients with biopsy-proven AIH-PBC overlap syndrome were included. Spearman correlation test was used to analyze the correlation of liver stiffness measurement (LSM) and fibrosis stage. Independent samples Student's t-test or one-way analysis of variance was used to compare quantitative variables. Receiver operating characteristics (ROC) curve was used to calculate the optimal cut-off values of LSM for predicting individual fibrosis stages. A comparison on the diagnostic accuracy for severe fibrosis was made between LSM and other serological scores. RESULTS: Patients with AIH-PBC overlap syndrome had higher median LSM than healthy controls (11.3 ± 6.4 kPa vs 4.3 ± 1.4 kPa, P < 0.01). LSM was significantly correlated with fibrosis stage (r = 0.756, P < 0.01). LSM values increased gradually with an increased fibrosis stage. The areas under the ROC curves of LSM for stages F ≥ 2, F ≥ 3, and F4 were 0.837 (95%CI: 0.729-0.914), 0.910 (0.817-0.965), and 0.966 (0.893-0.995), respectively. The optimal cut-off values of LSM for fibrosis stages F ≥ 2, F ≥ 3, and F4 were 6.55, 10.50, and 14.45 kPa, respectively. LSM was significantly superior to fibrosis-4, glutaglumyl-transferase/platelet ratio, and aspartate aminotransferase-to-platelet ratio index scores in detecting severe fibrosis (F ≥ 3) (0.910 vs 0.715, P < 0.01; 0.910 vs 0.649, P < 0.01; 0.910 vs 0.616, P < 0.01, respectively). CONCLUSION: TE can accurately detect hepatic fibrosis as a non-invasive method in patients with AIH-PBC overlap syndrome.

The immunobiology and clinical features of type 1 autoimmune polyglandular syndrome (APS-1).

Autoimmune Polyglandular Syndrome type 1 (APS-1) is a subtype of the autoimmune polyendocrine syndrome characterized by the simultaneous or sequential dysfunction of multiple endocrine or non-endocrine glands. A clinical diagnosis of APS-1 is typically based on the presence of at least two of three following criteria: chronic mucocutaneous candidiasis, hypoparathyroidism and adrenal insufficiency. The first identified causative mutated gene for APS-1 is autoimmune regulator (AIRE) encoding a critical transcription factor, which is primarily expressed in the medullary thymic epithelial cells (mTECs) for generating central immune tolerance. A wide range of chronic, debilitating complications, with no obvious correlation with genetics, makes a diagnosis of APS-1 challenging early in the disease course. Managing APS-1 is difficult due to its complexity, especially the intricate relationships within manifestations and genetic mutations. The past decades have witnessed dramatic progress in elucidating the function of AIRE and conducting large-scale cohort studies in APS-1. However, no clear evidence-based guidelines have been established in APS-1. In this review, we provide a detailed critical overview of the study history, epidemiology, clinical features, and related mechanisms of autoimmunity in APS-1, as well as currently available therapies for this autoimmune disorder.

RNA Sequencing and Bioinformatics Analysis Implicate the Regulatory Role of a Long Noncoding RNA-mRNA Network in Hepatic Stellate Cell Activation.

BACKGROUND/AIMS: To analyze the long noncoding (lncRNA)-mRNA expression network and potential roles in rat hepatic stellate cells (HSCs) during activation. METHODS: LncRNA expression was analyzed in quiescent and culture-activated HSCs by RNA sequencing, and differentially expressed lncRNAs verified by quantitative reverse transcription polymerase chain reaction (qRT-PCR) were subjected to bioinformatics analysis. In vivo analyses of differential lncRNA-mRNA expression were performed on a rat model of liver fibrosis. RESULTS: We identified upregulation of 12 lncRNAs and 155 mRNAs and downregulation of 12 lncRNAs and 374 mRNAs in activated HSCs. Additionally, we identified the differential expression of upregulated lncRNAs (NONRATT012636.2, NONRATT016788.2, and NONRATT021402.2) and downregulated lncRNAs (NONRATT007863.2, NONRATT019720.2, and NONRATT024061.2) in activated HSCs relative to levels observed in quiescent HSCs, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that changes in lncRNAs associated with HSC activation revealed 11 significantly enriched pathways according to their predicted targets. Moreover, based on the predicted co-expression network, the relative dynamic levels of NONRATT013819.2 and lysyl oxidase (Lox) were compared during HSC activation both in vitro and in vivo. Our results confirmed the upregulation of lncRNA NONRATT013819.2 and Lox mRNA associated with the extracellular matrix (ECM)-related signaling pathway in HSCs and fibrotic livers. CONCLUSION: Our results detailing a dysregulated lncRNA-mRNA network might provide new treatment strategies for hepatic fibrosis based on findings indicating potentially critical roles for NONRATT013819.2 and Lox in ECM remodeling during HSC activation.

Evaluation of transient elastography in assessing liver fibrosis in patients with autoimmune hepatitis.

BACKGROUND AND AIM: Transient elastography (TE) can reliably stage liver fibrosis via liver stiffness measurement (LSM) in chronic liver disease. However, the accuracy of TE for assessment of liver fibrosis in patients with autoimmune hepatitis (AIH) is still limited. We evaluate TE in staging liver fibrosis in AIH patients and compare with other noninvasive diagnostic tools. METHODS: A total of 100 patients with biopsy-proven AIH were included. The correlation between LSM and fibrosis stage was analyzed using Spearman correlation test. The optimal cut-off values of LSM were calculated for predicting individual fibrosis stages using receiver-operating characteristic curve. The diagnostic accuracy of LSM for severe fibrosis was compared with those of serum biochemical scores. RESULTS: Median LSM in AIH patients was higher than that of healthy controls (11.2 ± 8.2 kPa vs 4.3 ± 1.4 kPa, P < 0.01). LSM had significant correlation with fibrosis (r = 0.752, P < 0.01) and increased progressively with increasing fibrosis stages in AIH patients. AUROC values of LSM for stages F ≥ 2, F ≥ 3, and F4 were 0.878 (95%CI: 0.789-0.967), 0.883 (0.820-0.946), and 0.914 (0.852-0.976), respectively. The optimal cut-off values of LSM for fibrosis stages F ≥ 2, F ≥ 3, and F4 were 6.45, 8.75, and 12.50 kPa, respectively. LSM was superior to APRI score and FIB-4 score in detecting severe fibrosis (F ≥ 3). Serum ALT levels had minor effect on LSM values. CONCLUSIONS: Transient elastography is an accurate and reliable noninvasive tool in assessing liver fibrosis in AIH. Hepatic inflammatory activity had no significant effect on LSM determination.

The Management of Autoimmune Hepatitis Patients with Decompensated Cirrhosis: Real-World Experience and a Comprehensive Review.

There is a paucity of information related to the usefulness of corticosteroid therapy in autoimmune hepatitis (AIH) with decompensated cirrhosis. In this study, we sought to determine the therapeutic effect of corticosteroids in this special group of AIH patients. Eighty-two AIH patients with decompensated cirrhosis were included through a retrospective analysis from January 2009 to September 2015. Sixty-four patients were treated with corticosteroids while 18 patients did not receive any corticosteroids. Clinical, laboratory, and histological characteristics and outcomes were analyzed comparing corticosteroid-treated and untreated groups. Patients that did not receive corticosteroids were older than corticosteroid-treated patients and had a worse survival. In corticosteroid-treated group, 40 of 64 patients reverted to compensated state and 15 patients remained decompensated, while 9 patients experienced liver-related death or transplantation. Patients who reverted to compensated state had significantly greater ALT, AST, GGT, white blood cell count, and platelet levels at presentation. Changes (Δ) in total bilirubin (TBIL) and MELD scores at day 7 after starting corticosteroid therapy revealed favorable predictive effects of treatment outcomes. Survival was significantly greater in patients with a ΔTBIL <-0.196 mg/dL (p = 0.001) 7 days after treatment. Infection was the most common cause of death or transplantation in the patients with treatment failure. Although it cannot be determined whether the results were due to the therapy or underlying patient characteristics, survival was greater in the corticosteroid-treated group with the benefit being greatest in patients with the greatest decrease in TBIL at day 7 after starting corticosteroid therapy.

Treatment of cholestatic fibrosis by altering gene expression of Cthrc1: Implications for autoimmune and non-autoimmune liver disease.

Collagen triple helix repeat containing-1 (Cthrc1) is a documented specific inhibitor of TGF-ß signaling. Based on this observation, we developed the hypothesis that knocking in/knocking out the Cthrc1 gene in murine models of cholestasis would alter the natural history of cholestatic fibrosis. To study this thesis, we studied two murine models of fibrosis, first, common bile duct ligation (CBDL) and second, feeding of 3, 5-diethoxy-carbonyl-1, 4-dihydrocollidine (DDC). In both models, we administered well-defined adenoviral vectors that expressed either Cthrc1 or, alternatively, a short hairpin RNA (shRNA)-targeting Cthrc1 either before or after establishment of fibrosis. Importantly, when Cthrc1 gene expression was enhanced, we noted a significant improvement of hepatic fibrosis, both microscopically and by analysis of fibrotic gene expression. In contrast, when Cthrc1 gene expression was deleted, there was a significant exacerbation of fibrosis. To identify the mechanism of action of these significant effects produced by knocking in/knocking out Cthrc gene expression, we thence studied the interaction of Cthrc1 gene expression using hepatic stellate cells (HSCs) and human LX-2 cells. Importantly, we demonstrate that Cthrc1 is induced by TGF-ß1 via phospho-Smad3 binding to the promoter with subsequent transcription activation. In addition, we demonstrate that Cthrc1 inhibits TGF-ß signaling by accelerating degradation of phospho-Smad3 through a proteosomal pathway. Importantly, the anti-fibrotic effects can be recapitulated with a truncated fragment of Cthrc1. In conclusion, our findings uncover a critical negative feedback regulatory loop in which TGF-ß1 induces Cthrc1, which can attenuate fibrosis by accelerating degradation of phospho-Smad3.

Integrative analysis of the transcriptome and targetome identifies the regulatory network of miR-16: an inhibitory role against the activation of hepatic stellate cells.

Hepatic stellate cell (HSC) activation is the critical event of liver fibrosis. Abnormality of miR-16 expression induces their activation. However, the action model of miR-16 remains to be elucidated because of its multiple-targeted manner. Here, we report that miR-16 restoration exerted a wide-range impact on transcriptome (2,082 differentially expressed transcripts) of activated HSCs. Integrative analysis of both targetome (1,195 targets) and transcriptome uncovered the miR-16 regulatory network based upon bio-molecular interaction databases (BIND, BioGrid, Tranfac, and KEGG), cross database searching with iterative algorithm, Dijkstra's algorithm with greedy method, etc. Eight targets in the targetome (Map2k1, Bmpr1b, Nf1, Pik3r3, Ppp2r1a, Prkca, Smad2, and Sos2) served as key regulatory network nodes that mediate miR-16 action. A set of TFs (Sp1, Jun, Crebl, Arnt, Fos, and Nf1) was recognized to be the functional layer of key nodes, which mapped the signal of miR-16 to transcriptome. In result, the comprehensive action of miR-16 abrogated transcriptomic characteristics that determined the phenotypes of activated HSCs, including active proliferation, ECM deposition, and apoptosis resistance. Therefore, a multi-layer regulatory network based upon the integration of targetome and transcriptome may underlie the global action of miR-16, which suggesting it plays an inhibitory role in HSC activation.

Therapeutic potential of microRNA: a new target to treat intrahepatic portal hypertension?

Intrahepatic portal hypertension accounts for most of the morbidity and mortality encountered in patients with liver cirrhosis, due to increased portal inflow and intrahepatic vascular resistance. Most treatments have focused only on portal inflow or vascular resistance. However, miRNA multitarget regulation therapy may potentially intervene in these two processes for therapeutic benefit in cirrhosis and portal hypertension. This review presents an overview of the most recent knowledge of and future possibilities for the use of miRNA therapy. The benefits of this therapeutic modality--which is poorly applied in the clinical setting--are still uncertain. Increasing the knowledge and current understanding of the roles of miRNAs in the development of intrahepatic portal hypertension and hepatic stellate cells (HSCs) functions, as well as their potential as novel drug targets, is critical.

Dynamic expression of miR-126* and its effects on proliferation and contraction of hepatic stellate cells.

In our previous study, miR-126 was identified as one of the leading miRNAs that is downregulated during activation of hepatic stellate cells (HSCs). However, the roles and related mechanisms of miR-126 in HSCs are not understood. In this study, we compared expression of miR-126 during HSC activation both in vitro and in vivo. We also applied RNA interference to analyze the role and mechanism of miR-126(*) in the activation of HSCs. Restoring HSCs with Lv-miR-126(*) resulted in decreased proliferation, accumulation of extracellular matrix components, and cell contraction, while also negatively regulating the vascular endothelial growth factor (VEGF) signal transduction pathways by partially targeted VEGF-A. Thus, we postulate that miR-126 may be a biological marker for the activation of HSCs, and useful for reducing intrahepatic vascular resistance and improving the sinusoidal microcirculation in chronic liver diseases.

Effects of upregulated expression of microRNA-16 on biological properties of culture-activated hepatic stellate cells.

In our previous studies, we identified miR-16 as being downregulated during activation of hepatic stellate cells (HSCs) by microarray hybridization. However, the roles and related mechanisms of miR-16 in HSCs are not understood. In this study, The miRNA RNAi technique was used to analyze the effects of miR-16 on biological properties of HSCs in vitro. The lentiviral vector encoding miR-16 was constructed and transfected. Furthermore, the expression level of miR-16 was measured by real-time PCR. Cellular growth and proliferation capacity were assayed using the cell counting kit-8 (CCK-8). The apoptosis rate and cell-cycle distribution were measured by flow cytometry. Cell morphological characteristics were identified by phase-contrast microscopy, fluorescence microscopy and electron microscopy. The underlying mechanisms related to the changes in biological properties were assessed. The identity of the recombinant plasmid was confirmed by restriction endonuclease analysis and DNA sequencing. Virus titer was 10(8) > ifu/m. Restoring the intracellular miRNAs by miR-16 administration greatly reduced the expression levels of cyclin D1 (CD1). Cell-cycle arrest and typical features of apoptosis were detected in activated HSCs treated with pLV-miR-16. Our results indicate that transduction of miR-16 offers a feasible approach to significantly inhibit HSC proliferation and increase the apoptosis index. Thus, targeted transfer of miR-16 into HSC may be useful for the treatment of hepatic fibrosis.