Shah, Vijay H.

The fibrogenic wound-healing response in liver increases stiffness. Here, macro and microheterogeneity of liver stiffness correlate with HSC heterogeneity in a hepatic fibrosis mouse model. Fibrogenic HSCs localized in stiff collagen-high areas upregulate the expression of focal adhesion molecule FHL2, which, in turn, promotes extracellular matrix protein expression. These results demonstrate that stiffness heterogeneity at the whole organ, lobular, and cellular level drives an amplification loop of fibrogenesis through specific focal adhesion molecular pathways.

AbstractBackgroundThe impact of alcoholic hepatitis (AH) on health‐related quality of life (HRQOL) remains inadequately described. We aimed to characterize HRQOL in AH and heavy drinkers (HD), and its associations with clinical variables and outcomes.MethodsThis is a post hoc analysis of participants in the Translational Research and Evolving Alcoholic Hepatitis Treatment 001 study (NCT02172898). HRQOL was measured using Short Form Health Survey (SF‐36). Mean SF‐36 scores were compared in AH and HD with two‐sample t‐tests. Associations among clinical characteristics, 30‐day mortality, and SF‐36 mental and physical component scores (MC, PC) were investigated with generalized linear and logistic multivariate regression models. Trends of MC and PC scores were analyzed using one‐way ANOVA.ResultsParticipants with AH (n = 258) and HD (n = 181) were similar demographically. AH cases had a mean Model for End‐stage Liver Disease (MELD) score of 23 (7). AH cases had lower PC scores [37 (10) vs. 48 (11), p < 0.001] but higher MC scores [37 (13) vs. 32 (13), p < 0.001]. MC scores were independently associated with age, male gender, and daily alcohol consumption; PC scores were independently associated with age, BMI, alanine aminotransferase concentration, alkaline phosphatase concentration, white blood cell counts, and the presence of ascites. With each 5‐point decrease in the baseline PC score, the adjusted odds of dying within 30 days increased by 26.7% (95% CI 1% to 46%). Over time, HRQOL in AH improved (day 0 to day 180 delta PC score: 4.5 ± 1.7, p = 0.008; delta MC score: 9.8 ± 2.0, p < 0.001). Participants with a MELD score <15 by day 180 had greater increases in PC scores than those with MELD score ≥15 (delta PC score 7.1 ± 1.8 vs. −0.7 ± 2.3, p = 0.009), while those abstinent by day 180 had greater increases in MC scores than those who were not abstinent (delta MC score 9.1 ± 1.8 vs. 2.8 ± 2.4, p = 0.044).ConclusionsHRQOL is poor in AH and HD in a domain‐specific pattern. Independent of MELD score, lower baseline HRQOL is associated with higher 30‐day mortality. Over time, HRQOL improves with greater gains seen in individuals with improved MELD scores and those who were abstinent.

Hepatic fibrosis is driven by deposition of matrix proteins following liver injury. Hepatic stellate cells (HSCs) drive fibrogenesis, producing matrix proteins, including procollagen I, which matures into collagen I following secretion. Disrupting intracellular procollagen processing and trafficking causes endoplasmic reticulum stress and stress‐induced HSC apoptosis and thus is an attractive antifibrotic strategy. We designed an immunofluorescence‐based small interfering RNA (siRNA) screen to identify procollagen I trafficking regulators, hypothesizing that these proteins could serve as antifibrotic targets. A targeted siRNA screen was performed using immunofluorescence to detect changes in intracellular procollagen I. Tumor necrosis factor receptor associated factor 2 and noncatalytic region of tyrosine kinase‐interacting kinase (TNIK) was identified and interrogated in vitro and in vivo using the TNIK kinase inhibitor NCB‐0846 or RNA interference‐mediated knockdown. Our siRNA screen identified nine genes whose knockdown promoted procollagen I retention, including the serine/threonine kinase TNIK. Genetic deletion or pharmacologic inhibition of TNIK through the small molecule inhibitor NCB‐0846 disrupted procollagen I trafficking and secretion without impacting procollagen I expression. To investigate the role of TNIK in liver fibrogenesis, we analyzed human and murine livers, finding elevated TNIK expression in human cirrhotic livers and increased TNIK expression and kinase activity in both fibrotic mouse livers and activated primary human HSCs. Finally, we tested whether inhibition of TNIK kinase activity could limit fibrogenesis in vivo. Mice receiving NCB‐0846 displayed reduced CCl4‐induced fibrogenesis compared to CCl4 alone, although α‐smooth muscle actin levels were unaltered. Conclusions: Our siRNA screen effectively identified TNIK as a key kinase involved in procollagen I trafficking in vitro and hepatic fibrogenesis in vivo.

Abstract Alcohol‐associated liver disease (ALD) is emerging worldwide as the leading cause of liver‐related morbidity, mortality, and indication for liver transplantation. The ALD Special Interest Group and the Clinical Research Committee at the digital American Association for the Study of Liver Diseases meeting in November 2020 held the scientific sessions to identify clinical unmet needs in ALD, and addressing these needs using clinical research methodologies. Of several research methodologies, the sessions were focused on (a) studying disease burden of ALD using large administrative databases, (b) developing biomarkers for noninvasive diagnosis of alcohol‐associated hepatitis (AH) and estimation of disease prognosis, (c) identifying therapeutic targets for ALD and AH, (d) deriving accurate models to predict prognosis or posttransplant alcohol relapse as a basis for developing treatment algorithm and a uniform protocol on patient‐selection criteria for liver transplantation, and (e) examining qualitative research methodologies in studying the barriers to implementation of multidisciplinary integrated care model by hepatology and addiction teams for the management of dual pathology of liver disease and of alcohol use disorder. Prospective multicenter studies are required to address many of these clinical unmet needs. Further, multidisciplinary care models are needed to improve long‐term outcomes in patients with ALD.

Abstract Background Magnetic resonance imaging (MRI) and MRI‐based elastography (MRE) are the most promising noninvasive techniques in assessing liver diseases. The purpose of this study was to evaluate an advanced multiparametric imaging method for staging disease and assessing treatment response in realistic preclinical alcohol‐associated liver disease (ALD). Methods We utilized four different preclinical mouse models in our study: Model 1—mice were fed a fast‐food diet and fructose water for 48 weeks to induce nonalcoholic fatty liver disease; Model 2—mice were fed chronic‐binge ethanol (EtOH) for 10 days or 8 weeks to induce liver steatosis/inflammation. Two groups of mice were treated with interleukin‐22 at different time points to induce disease regression; Model 3—mice were administered CCl 4 for 2 to 4 weeks to establish liver fibrosis followed by 2 or 4 weeks of recovery; and Model 4—mice were administered EtOH plus CCl 4 for 12 weeks. Mouse liver imaging biomarkers including proton density fat fraction (PDFF), liver stiffness (LS), loss modulus (LM), and damping ratio (DR) were assessed. Liver and serum samples were obtained for histologic and biochemical analyses. Ordinal logistic regression and generalized linear regression analyses were used to model the severity of steatosis, inflammation, and fibrosis, and to assess the regression of these conditions. Results Multiparametric models with combinations of biomarkers (LS, LM, DR, and PDFF) used noninvasively to predict the histologic severity and regression of steatosis, inflammation, and fibrosis were highly accurate (area under the curve > 0.84 for all). A three‐parameter model that incorporates LS, DR, and ALT predicted histologic fibrosis progression ( r = 0.84, p < 0.0001) and regression ( r = 0.79, p < 0.0001) as measured by collagen content in livers. Conclusion This preclinical study provides evidence that multiparametric MRI/MRE can be used noninvasively to assess disease severity and monitor treatment response in ALD.

Physiologic aging leads to attrition of telomeres and replicative senescence. An acceleration of this process has been hypothesized in the progression of chronic liver disease. We sought to examine the association of telomere length (TL) with liver disease and its impact on mortality risk. A cohort of 7,072 adults with leukocyte TL measurements from the National Health and Nutrition Examination Survey 1999‐2002 with mortality follow‐up through 2015 was analyzed. Liver disease was defined by aminotransferase levels and classified into etiology‐based and advanced fibrosis categories. Multivariable‐adjusted linear regression models estimated effect sizes, with 95% confidence intervals (CIs), of the presence of liver disease on TL. Cox regression models evaluated associations between TL and all‐cause mortality risk using adjusted hazard ratios (HRs). The cohort was representative of the US population with mean age 46.1 years and mean TL 5.79 kilobase pairs. No overall association between TL and liver disease was found; however, there was a significant negative association of TL and advanced liver fibrosis in individuals aged 65 and above. The liver disease cohort (HR 1.22, 95% CI 0.99‐1.51) and those with metabolic syndrome (HR 1.26, 95% CI 0.96‐1.67) had increased mortality risk with shorter TL. The relationship between TL and all‐cause mortality was stronger in women (HR 1.51, 95% CI 1.02‐2.23) and in non‐Hispanic Whites (HR 1.37, 95% CI 1.02‐1.84). Conclusion: Shortened leukocyte TL is independently associated with advanced liver disease at older ages, and with a higher risk of all‐cause mortality in those with liver disease. These associations reaffirm the need to better understand the role of telomeres in the progression of liver disease.

Primary sclerosing cholangitis (PSC) is a chronic fibroinflammatory disease of the biliary tract characterized by cellular senescence and periportal fibrogenesis. Specific disease features that are cell intrinsic and either genetically or epigenetically mediated remain unclear due in part to a lack of appropriate, patient‐specific, in vitro models. Recently, our group developed systems to create induced pluripotent stem cell (iPSC)‐derived cholangiocytes (iDCs) and biliary epithelial organoids (cholangioids). We use these models to investigate whether PSC cholangiocytes are intrinsically predisposed to cellular senescence. Skin fibroblasts from healthy controls and subjects with PSC were reprogrammed to pluripotency, differentiated to cholangiocytes, and subsequently grown in three‐dimensional matrigel‐based culture to induce formation of cholangioids. RNA sequencing (RNA‐seq) on iDCs showed significant differences in gene expression patterns, including enrichment of pathways associated with cell cycle, senescence, and hepatic fibrosis, that correlate with PSC. These pathways also overlapped with RNA‐seq analysis on isolated cholangiocytes from subjects with PSC. Exome sequencing on the subjects with PSC revealed genetic variants of unknown significance in the genes identified in these pathways. Three‐dimensional culture revealed smaller size, lack of a central lumen, and increased cellular senescence in PSC‐derived cholangioids. Congruent with this, PSC‐derived iDCs showed increased secretion of the extracellular matrix molecule fibronectin as well as the inflammatory cytokines interleukin‐6, and chemokine (C‐C motif) ligand 2. Conditioned media (CM) from PSC‐derived iDCs more potently activated hepatic stellate cells compared to control CM. Conclusion: We demonstrated efficient generation of iDCs and cholangioids from patients with PSC that show disease‐specific features. PSC cholangiocytes are intrinsically predisposed to cellular senescence. These features are unmasked following biliary differentiation of pluripotent stem cells and have functional consequences in epithelial organoids.