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The liver transplantation (LT) population is aging, with the need for transplant being driven by the growing prevalence of nonalcoholic steatohepatitis (NASH). Older LT recipients with NASH may be at an increased risk for adverse outcomes after LT. Our objective is to characterize outcomes in these recipients in a large multicenter cohort. All primary LT recipients ≥65 years from 2010 to 2016 at 13 centers in the Re-Evaluating Age Limits in Transplantation (REALT) consortium were included. Of 1023 LT recipients, 226 (22.1%) were over 70 years old, and 207 (20.2%) had NASH. Compared with other LT recipients, NASH recipients were older (68.0 versus 67.3 years), more likely to be female (47.3% versus 32.8%), White (78.3% versus 68.0%), Hispanic (12.1% versus 9.2%), and had higher Model for End-Stage Liver Disease–sodium (21 versus 18) at LT (P < 0.05 for all). Specific cardiac risk factors including diabetes with or without chronic complications (69.6%), hypertension (66.3%), hyperlipidemia (46.3%), coronary artery disease (36.7%), and moderate-to-severe renal disease (44.4%) were highly prevalent among NASH LT recipients. Graft survival among NASH patients was 90.3% at 1 year and 82.4% at 3 years compared with 88.9% at 1 year and 80.4% at 3 years for non-NASH patients (log-rank P = 0.58 and P = 0.59, respectively). Within 1 year after LT, the incidence of graft rejection (17.4%), biliary strictures (20.9%), and solid organ cancers (4.9%) were comparable. Rates of cardiovascular (CV) complications, renal failure, and infection were also similar in both groups. We observed similar posttransplant morbidity and mortality outcomes for NASH and non-NASH LT recipients. Certain CV risk factors were more prevalent in this population, although posttransplant outcomes within 1 year including CV events and renal failure were similar to non-NASH LT recipients.

Background & Aims Non-alcoholic steatohepatitis is a leading cause of end-stage liver disease. Hepatic steatosis and lipotoxicity cause chronic necroinflammation and direct hepatocellular injury resulting in cirrhosis, end-stage liver disease and hepatocellular carcinoma. Emricasan is a pan-caspase inhibitor that inhibits excessive apoptosis and inflammation; it has also been shown to decrease portal pressure and improve synthetic function in mice with carbon tetrachloride-induced cirrhosis. Methods This double-blind, placebo-controlled study randomized 217 individuals with decompensated NASH cirrhosis 1:1:1 to emricasan (5 mg or 25 mg) or placebo. Patients were stratified by decompensation status and baseline model for end-stage liver disease-sodium (MELD-Na) score. The primary endpoint comprised all-cause mortality, a new decompensation event (new or recurrent variceal hemorrhage, new ascites requiring diuretics, new unprecipitated hepatic encephalopathy ≥grade 2, hepatorenal syndrome, spontaneous bacterial peritonitis), or an increase in MELD-Na score ≥4 points. Results There was no difference in event rates between either of the emricasan treatment groups and placebo, with hazard ratios of 1.02 (95% CI 0.59–1.77; p = 0.94) and 1.28 (95% CI 0.75–2.21; p = 0.37) for 5 mg and 25 mg of emricasan, respectively. MELD-Na score progression was the most common outcome. There was no significant effect of emricasan treatment on MELD-Na score, international normalized ratio, total serum bilirubin, albumin level or Child-Pugh score. Emricasan was generally safe and well-tolerated. Conclusions Emricasan was safe but ineffective for the treatment of decompensated NASH cirrhosis. However, this study may guide the design and conduct of future clinical trials in decompensated NASH cirrhosis. Lay summary Patients with decompensated cirrhosis related to non-alcoholic steatohepatitis are at high risk of additional decompensation events and death. Post hoc analyses in previous pilot studies suggested that emricasan might improve portal hypertension and liver function. In this larger randomized study, emricasan did not decrease the number of decompensation events or improve liver function in patients with a history of decompensated cirrhosis related to non-alcoholic steatohepatitis. ClinicalTrials.gov Identifier NCT03205345 .

Background and aims Liver disease is prevalent in the United States, and as the population ages, an increasing number of patients are anticipated to present for care. The state of the current hepatology workforce and future demand for hepatology providers is not known. The aim of this study was to model future projections for hepatology workforce demand. Approach and results A workforce study of hepatology providers in the United States was completed using primary and secondary data sources. An integrated workforce framework model was used that combined socioeconomic factors that drive economic demand, epidemiological factors that drive need, and utilization rates of health care services. Supply and demand projections were calculated for adult and pediatric hepatology professionals. Sensitivity analyses were conducted to cover the feasible range of these assumptions. An electronic survey of American Association for the Study of Liver Diseases (AASLD) members whose practice included 50% or more hepatology was conducted. In 2018, the adult and pediatric workforce included 7,296 and 824 hepatology providers, respectively, composed of hepatologists, gastroenterologists, and advanced practice providers whose practice was ≥50% hepatology. The modeling analysis projects that in 2023, 2028, and 2033, there will be shortages of 10%, 23%, and 35% adult hepatology providers, respectively, and 19%, 20%, and 16% pediatric hepatology providers, respectively. In sensitivity analyses, a shortage of hepatology providers is predicted even under optimistic assumptions. Among the respondents to the survey, the median age was higher among gastroenterologists and general hepatologists compared with transplant hepatologists. The most common category treated by transplant hepatologists was general hepatology. Conclusions There is an impending critical shortage of adult and pediatric hepatology providers. Strategies are needed to encourage clinicians to pursue hepatology, especially in areas outside of transplant centers.

BACKGROUND Telomere syndromes have their most common manifestation in idiopathic pulmonary fibrosis and emphysema. The short telomere defect in these patients may manifest systemically as bone marrow failure and liver disease. We sought to understand the causes of dyspnea in telomerase and telomere gene mutation carriers who have no parenchymal lung disease. METHODS Clinical and pathologic data were reviewed as part of a Johns Hopkins-based natural history study of short telomere syndromes including dyskeratosis congenita. RESULTS Hepatopulmonary syndrome (HPS) was diagnosed in nine of 42 cases (21%). Their age at presentation was significantly younger than that of cases initially presenting with pulmonary fibrosis and emphysema (median, 25 years vs 55 years; P « .001). Cases had evidence of intra- and extrapulmonary arteriovascular malformations that caused shunt physiology. Nodular regenerative hyperplasia was the most frequent histopathologic abnormality, and it was seen in the absence of cirrhosis. Dyspnea and portal hypertension were progressive, and the median time to death or liver transplantation was 6 years (range, 4-10 years; n=6). In cases that underwent liver transplantation, dyspnea and hypoxia improved, but pulmonary fibrosis subsequently developed. CONCLUSIONS This report identifies HPS as a frequent cause of dyspnea in telomerase and telomere gene mutation carriers. While it usually precedes the development of parenchymal lung disease, HPS may also co-occur with pulmonary fibrosis and emphysema. Recognizing this genetic diagnosis is critical for management, especially in the lung and liver transplantation setting.

SummaryBackground The relationships between primary sclerosing cholangitis (PSC) and the environment are largely unknown. Aim To validate associations reported in previous studies and to identify novel environmental exposures among PSC patients. Methods We performed a multicenter, case–control analysis utilising self-administered questionnaires. Responses between cases (n = 1000) and controls (n = 663) were compared using multivariable logistic regression adjusted for age and gender. The model was further stratified based on inflammatory bowel disease (IBD) status (with IBD n = 741 without IBD n = 259). Results Smoking was associated with PSC only when IBD was present (OR, 0.5; 95% CI 0.4–0.7) but not among those PSC patients without IBD (OR, 0.9; 95% CI 0.7–1.2). Compared to controls, women with PSC (irrespective of the presence of IBD) were less likely to have received hormone replacement therapy (HRT; OR, 0.5; 95% CI 0.4–0.7) and were more likely to have recurrent urinary tract infections (OR, 1.6; 95% CI 1.2–2.3). PSC patients regardless of gender or IBD status were less likely to eat fish (OR, 0.4; 95% CI 0.3–0.6) and grilled/barbecued meat (OR, 0.8; 95% CI 0.7–0.9). In contrast, PSC patients with and without IBD were more likely to consume steak/burgers that were more well done (OR, 1.3; 95% CI 1.2–1.5). Conclusions IBD (rather than PSC) is associated with smoking. Women with PSC are more likely to have recurrent urinary tract infections and less likely to receive HRT. Dietary intake and methods of food preparation differ in PSC patients when compared to controls.

Choice of therapy in early hepatocellular carcinoma (HCC) is controversial, and no broad consensus exists as to how patient and tumor characteristics should be used to guide choice of therapy. We have previously reported on decision making in early HCC by liver surgeons. In the present study, we quantified the impact of clinical factors on choice of therapy for early HCC by gastroenterologists and hepatologists. Physicians who treat HCC were invited to complete a web-based survey including ten case scenarios that systematically varied across seven clinical factors. Choice of therapy—liver transplantation (LT), liver resection (LR), radiofrequency ablation or intra-arterial therapy—was analyzed using multinomial logistic regression models. Tumor number and size, type of resection required, biological Model for End-Stage Liver Disease (MELD) score, and platelet count had the largest effects on choice of therapy. For example, LR was more likely to be recommended over LT for patients with small solitary tumors versus multiple tumors [relative risk ratio (RRR) 3.63], those who would require a minor versus major LR (RRR 3.39), those with lower biological MELD score (6 vs. 10; RRR 1.95), and those with a higher platelet count (150,000/μL vs. 70,000/μL; RRR 2.77). In contrast, serum α-fetoprotein level and etiology of cirrhosis were not associated with choice of therapy. No physician-related factors studied had an impact on choice of therapy. The clinical factors weighed most heavily by gastroenterologists and hepatologists are quite similar to those considered important by surgeons. There was good consensus among gastroenterologists and hepatologists as to the factors used to choose therapy.

Effects of chronic cadmium exposure on liver disease and liver-related mortality are unknown. We evaluated the association of creatinine-corrected urinary cadmium levels with hepatic necroinflammation, non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), liver-related mortality, and liver cancer mortality in the US general population.We analyzed the relationship of individuals in the top quartile for urinary cadmium measured in 12,732 adults who participated in the Third National Health and Nutrition Examination Survey in 1988-1994 (NHANES III), and hepatic necroinflammation, NAFLD, and NASH. Associations between cadmium, liver-related mortality, and liver cancer mortality were evaluated in the NHANES III mortality follow-up study.The cutoffs for highest quartile of urinary cadmium per gram of urinary creatinine were 0.65 and 0.83 μg/g for men and women, respectively (P 0.001). After multivariate adjustment for other factors including smoking, the odds ratios [95 % confidence intervals (CI)] for hepatic necroinflammation, NAFLD, and NASH associated with being in the top quartile of cadmium levels by gender, were 2.21 (95 % CI, 1.64-3.00), 1.30 (95 % CI, 1.01-1.68) and 1.95 (95 % CI, 1.11-3.41) for men and 1.26 (95 % CI, 1.01-1.57), 1.11 (95 % CI, 0.88-1.41) and 1.34 (95 % CI, 0.72-2.50) for women, respectively. The hazard ratios for liver-related mortality and liver cancer mortality for both genders were 3.42 (95 % CI, 1.12-10.47) and 1.25 (95 % CI, 0.37-4.27).Environmental cadmium exposure was associated with hepatic necroinflammation, NAFLD, and NASH in men, and hepatic necroinflammation in women. Individuals in the top quartile of creatinine-corrected urinary cadmium had over a threefold increased risk of liver disease mortality but not in liver cancer related mortality.

Hepatic fibrosis and cirrhosis result from the excessive deposition of predominantly type I collagen, which is composed of two α1 and one α2 chains. 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3)2, the active form of vitamin D, is formed by sequential 25 and 1a hydroxylation in the liver and kidney respectively (1). Low serum levels of 25-hydroxyvitamin D are common in chronic cholestatic and non-cholestatic liver disease (2–4) with the lowest levels observed in patients with severe hepatic fibrosis (4). 1,25-(OH)2D3 was shown to reduce type I collagen mRNA and collagen synthesis in osteoclasts of rat fetal calvaria (5), the activity of the rat α1(I) collagen promoter in transfected rat osteosarcoma cells (6) and to inhibit transforming growth factor beta 1 (TGFβ1)-induced fibroblast proliferation and type I collagen expression (7). More recently 1,25-(OH)2D3 was shown to decrease rat α1(I) collagen promoter activity in transfected rat stellate cells, decrease α1(I) collagen mRNA and collagen content in the rat stellate cells and to diminish thioacetamide-induced liver fibrosis in rats (8). 1,25-(OH)2D3 is the ligand of the vitamin D receptor (VDR) which mediates its biological effects. Most of the actions of VDR are mediated by heterodimers of VDR with retinoid X receptor (VDR-RXR heterodimers) which bind to vitamin D response elements (VDREs) in promoters of vitamin D responsive genes (9). VDREs usually consist of two core motifs in the form of Pug (G/T)TCA (X)3 PuG(G/T)TCA (10). However, several variations of these motifs can be tolerated (11). VDRE has been identified in the murine α1(I) collagen promoter (12), however, we found no reports of identification of VDREs in the human α1(I) collagen promoter. VDR was also shown to modulate the expression of genes that lack VDRE via Sp1 binding sites by forming a complex with Sp1 (13). Sp1 binds to the human α1(I) collagen promoter ( − 164 to −142), forms a complex with Smads and is a powerful mediator of the activating effect of TGFβ on the collagen promoter (14, 15). The aim of this study was to determine the effect of 1,25-(OH)2D3 on the human α1(I) collagen promoter, collagen formation by human stellate LX-2 cells and the mechanism of the effect of VDR on the promoter.

The field of hepatology has experienced dramatic changes since the last workforce study in hepatology over 15 years ago. Hepatology practice has been dominated by hepatitis C but is now being overtaken by patients with nonalcoholic fatty liver disease. Expertise once attainable only through informal training, hepatology now has an accredited fellowship pathway and is recognized as a distinct discipline from gastroenterology with its own board certification. These changes that have occurred since the last workforce study in the prevalence and therapy of liver diseases and training may impact workforce needs. The time has come to conduct an updated analysis of the state of the hepatology workforce. The purpose of this article is to discuss the current issues facing training and workforce in hepatology and propose the next steps in conducting a workforce study. (Hepatology 2017;65:336-340).

Higher prevalence of nonalcoholic fatty liver disease (NAFLD) in men and postmenopausal women than in premenopausal women has suggested a potential role of sex hormones in the pathogenesis of the disease. We sought to evaluate the association between oral contraceptive pills (OCP) and NAFLD and to determine whether adiposity mediates any effect.We included 4338 women aged 20-60 years who were enrolled in the Third National Health and Nutrition Examination Survey from 1988 to 1994 in a population-based cross-sectional study. We defined NAFLD as moderate-severe steatosis on ultrasonography in women without excessive alcohol use or other identifiable causes. OCP use was based on self-report and was categorized as never, former or current use.The overall weighted prevalence of NAFLD was 11.6 % but lower in current (6.7 %) than in former (12.0 %) or never users (15.6 %, P = 0.016). In the multivariable model, current OCP users experienced a 50 % lower odds of NAFLD than never users (adjusted odds ratio 0.50; 95 % confidence interval 0.26, 0.98) after adjusting for age, race/ethnicity, smoking status, history of diabetes or hypertension and education. Further adjustment for body mass index or waist circumference significantly attenuated the OCP-NAFLD relationship.In this large US-representative population, OCP use was associated with reduced odds of NAFLD. However, this association could be mediated or confounded by adiposity. Prospective studies are needed to further clarify the causal role of sex hormone.

Background: The effects of ethanol and acetaldehyde on uptake of glycerol and on cell size of hepatocytes and a role Aquaporin 9 (AQP9), a glycerol transport channel, were evaluated. Methods: The studies were done in primary rat and mouse hepatocytes. The uptake of [14C] glycerol was determined with hepatocytes in suspension. For determination of cell size, rat hepatocytes on coated dishes were incubated with a lipophilic fluorochrome that is incorporated into the cell membrane and examined by confocal microscopy. A three-dimensional z scan of the cell was performed, and the middle slice of the z scan was used for area measurements. Results: Acute exposure to acetaldehyde, but not to ethanol, causes a rapid increase in the uptake of glycerol and an increase in hepatocyte size, which was inhibited by HgCl2, an inhibitor of aquaporins. This was not observed in hepatocytes from AQP9 knockout mice, nor observed by direct application of acetaldehyde to AQP9 expressed in Xenopus Laevis oocytes. Prolonged 24-hour exposure to either acetaldehyde or ethanol did not result in an increase in glycerol uptake by rat hepatocytes. Acetaldehyde decreased AQP9 mRNA and AQP9 protein, while ethanol decreased AQP9 mRNA but not AQP9 protein. Ethanol, but not acetaldehyde, increased the activities of glycerol kinase and phosphoenolpyruvate carboxykinase. Conclusions: The acute effects of acetaldehyde, while mediated by AQP9, are probably influenced by binding of acetaldehyde to hepatocyte membranes and changes in cell permeability. The effects of ethanol in enhancing glucose kinase, and phosphoenolpyruvate carboxykinase leading to increased formation of glycerol-3-phosphate most likely contribute to alcoholic fatty liver.

The drop-off risk for patients awaiting liver transplantation for hepatocellular carcinoma (HCC) is 22%. Transplant liver availability is expected to worsen, resulting in longer waiting times and increased drop-off rates. Our aim was to determine whether chemoembolization can decrease this risk.Eighty-seven consecutive HCC patients listed for liver transplant (Milan criteria) underwent statistical comparability adjustments using the propensity score (Wilcoxon, Fisher's, and chi-square tests). Forty-three nonchemoembolization patients and 22 chemoembolization patients were comparable for Child-Pugh and Model for End-Stage Liver Disease scores, tumor size and number, alpha fetoprotein (AFP) levels, and cause of cirrhosis. We calculated the risk of dropping off the transplant list by assigning a transplant time to those who dropped off (equal probability with patients who were on the list longer than the patient in question). The significance level was obtained by calculating the simulation distribution of the difference compared with the permutations of chemoembolization versus nonchemoembolization assignment of the patients. Kaplan-Meier estimators (log-rank test) were used to determine survival rates.Median follow-up was 187 ± 110 weeks (range 38 to 435, date of diagnosis). The chemoembolization group had an 80% drop-off risk decrease (15% nonchemoembolization versus 3% chemoembolization, p = 0.04). Although survival was better for the chemoembolization group, it did not reach statistical significance. Two-year survival for the nonchemoembolization and chemoembolization group was 57.3% ± 7.1% and 76.0% ± 7.9%, respectively (p = 0.078).Chemoembolization appears to result in a significant decrease in the risk of dropping off liver transplant list for patients with HCC and results in a tendency toward longer survival.

Transforming growth factor b 1( TGFb1) plays a crucial role in the induction of the epithelial-to-mesenchymal transition (EMT) in hepatocytes, which contributes to the pathogenesis of liver fibrosis. The inhibition of the TGFb1 cascade suppresses EMT and the resultant fibrosis. In this study, we focus on EMT-induced fibrosis in hepatocytes and the epigenetic regulation of the type I collagen gene. Histone acetylation is an important, major epigenetic mechanism that modulates gene transcription. We evaluated the epigenetic regulation of type I collagen in alpha mouse liver 12 hepatocytes (an untransformed mouse cell line) that had undergone EMT after treatment with TGFb1. The histone deacetylase inhibitor trichostatin A (TSA) inhibited EMT; this was reflected by the preservation of epithelial markers and function (E-cadherin and albumin). Fibrosis, the ultimate outcome of EMT, was abolished by TSA; this was indicated by the inhibition of type I collagen deposition. TSA exerted its anti-EMT effects by deactivating the mothers against decapentaplegic homolog 3 (Smad3)/Smad4 transcription complex and by interfering with p300, a coactivator of the type I collagen promoter, and preventing its binding to Smad3. TSA also restored Friend leukemia virus integration 1, an inhibitor of the type I collagen gene. TGFb1-induced EMT and its inhibition by TSA were replicated in human primary hepatocytes. Conclusion: Histone deacetylase inhibition abrogates TGFb1induced EMT in hepatocytes and reverses EMT-induced fibrosis by epigenetic modulation of type I collagen. (HEPATOLOGY 2010;52:1033-1045)

Despite advances in hepatitis C therapy and better knowledge of viral/host factors related to disease progression, the hepatitis C virus remains the leading cause of chronic liver disease, causing progression to end-stage liver disease (ESLD) as well as the development of hepatocellular carcinoma. Because hepatitis C virus acquisition is linked to an addictive behavior (ie, injection drug use), any perceived dependence has been a major reason for treatment denial as well as exclusion from clinical trials. Of special interest are two such dependences: drinking alcohol and smoking marijuana (cannabis). We review the available evidence for the effects of alcohol and cannabis on liver disease progression in chronic hepatitis C, and conclude with recommendations regarding the use of these two substances in the setting of chronic hepatitis C.

Animal models of hepatic steatosis and steatohepatitis have improved our understanding of the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Three models, genetically obese ob/ob mice, lipoatrophic mice and normal rats fed choline-deficient, methionine-restricted diets, have been particularly informative. All support the multiple 'hit' hypothesis for NAFLD pathogenesis that suggests that fatty livers are unusually vulnerable to oxidants and develop steatohepatitis when secondary insults generate sufficient oxidants to cause liver cell death and inflammation. Steatohepatitis, in turn, increases sensitivity to other insults that induce hepatic fibrosis, promoting the evolution of cirrhosis. Early during NAFLD pathogenesis, inhibitor kappa kinase beta (IKKbeta), an enzyme that induces tumour necrosis factor alpha (TNFalpha) and other proinflammatory cytokines, is activated and this causes insulin resistance. Inhibition of IKKbeta or TNFalpha improves insulin sensitivity, steatosis and steatohepatitis in animals, suggesting novel strategies to prevent and treat early NAFLD in humans.

Although ethanol is known to sensitize hepatocytes to tumor necrosis factor (TNF) lethality, the mechanisms involved remain controversial. Recently, others have shown that adding TNFalpha to cultures of ethanol-pretreated hepatocytes provokes the mitochondrial permeability transition, cytochrome c release, procaspase 3 activation, and apoptosis. Although this demonstrates that ethanol can sensitize hepatocytes to TNF-mediated apoptosis, the hepatic inflammation and ballooning hepatocyte degeneration that typify alcohol-induced liver injury suggest that other mechanisms might predominate in vivo. To evaluate this possibility, acute responses to lipopolysaccharide (LPS), a potent inducer of TNFalpha, were compared in mice that had been fed either an ethanol-containing or control diet for 5 weeks. Despite enhanced induction of cytokines such as interleukin (IL)-10, IL-15, and IL-6 that protect hepatocytes from apoptosis, ethanol-fed mice exhibited a 4-5-fold increase in serum alanine aminotransferase after LPS, confirming increased liver injury. Six h post-LPS histology also differed notably in the two groups, with control livers demonstrating only scattered apoptotic hepatocytes, whereas ethanol-exposed livers had large foci of ballooned hepatocytes, inflammation, and scattered hemorrhage. No caspase 3 activity was noted during the initial 6 h after LPS in ethanol-fed mice, but this tripled by 1.5 h after LPS in controls. Procaspase 8 cleavage and activity of the apoptosis-associated kinase, Jun N-terminal kinase, were also greater in controls. In contrast, ethanol exposure did not inhibit activation of cytoprotective mitogen-activated protein kinases and AKT or attenuate induction of the anti-apoptotic factors NF-kappaB and inducible nitric oxide synthase. Consistent with these responses, neither cytochrome c release, an early apoptotic response, nor hepatic oligonucleosomal DNA fragmentation, the ultimate consequence of apoptosis, was increased by ethanol. Thus, ethanol exacerbates TNF-related hepatotoxicity in vivo without enhancing caspase 3-dependent apoptosis.

Obesity increases the risk for liver disease, including liver cancer. The mechanisms for this association are not well understood. At the very least, obesity might function as a comorbidity factor, accentuating processes (such as microsomal enzyme induction or pro-inflammatory cytokine production) that mediate liver damage caused by alcohol, hepatotoxic drugs, or certain viral infections. However, a growing body of evidence suggests that obesity-related insulin resistance plays a fundamental role in the initiation and progression of liver damage and liver cancer by altering the viability of liver cells. Efforts to delineate the molecular mechanisms that mediate insulin’s actions on cellular apoptosis and proliferation are increasing, and should help us design more effective therapies to prevent and treat obesity-related liver diseases.

In the United States, the burden of liver-related diseases is important. Over the last 2 decades, liver-related mortality ranked among the top 12 causes of death, and among adults aged 45–54 years, it has been repeatedly listed as the fourth leading cause of death (1, 2). Nonalcoholic fatty liver disease (NAFLD) is thought to be the most common chronic liver disease in the Western world (3–5). However, US estimates of the prevalence of NAFLD are lacking, and previous nationally representative studies have been limited by the use of surrogate markers of liver disease, namely liver enzymes, with estimates in the range of 3%–23% (6–9). Studies that have used more sensitive, specific, or direct methods have been limited by small sample size or by the use of convenience samples and report a range in the prevalence of NAFLD (19%–46%) (10, 11). Although the “gold standard” for diagnosing and staging NAFLD is histology, abdominal unltrasonography allows its detection (4, 5). NAFLD was traditionally thought to be a benign condition; however, longitudinal studies have shown that it can progress to nonalcoholic steatohepatitis and fibrosis (12–14), leading to cirrhosis (15, 16). Also, there is increasing evidence suggesting that NAFLD may play a significant role in the strong association between obesity and the development of liver cancer (17, 18). Large, population-based estimates of the prevalence of NAFLD as detected by ultrasonography are available for other Western and non-Western countries and show that its prevalence parallels that of obesity (11). For the United States, there are no representative data regarding the prevalence and epidemiology of this condition. These estimates are key to assessing the magnitude of the disease and planning and projecting the health-care costs and the burden associated with liver disease. The Third National Health and Nutrition Examination Survey (NHANES III) was a large and representative survey of the noninstitutionalized US civilian population; it included gallbladder ultrasonography of all participants aged 20–74 years. Recently, we reevaluated these ultrasonography videotapes to assess the presence of hepatic steatosis. By using these ultrasonography data, our aims were 1) to estimate the prevalence of any hepatic steatosis and NAFLD in the United States by key sociodemographic characteristics and 2) to examine metabolic, anthropometric, and laboratory correlates of hepatic steatosis and NAFLD.

SummaryBackground Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent condition. Emerging evidence suggests that vitamin D may play a role in the pathogenesis of NAFLD. Aim To review systematically the association between vitamin D levels, measured as serum 25-hydroxy vitamin D [25(OH)D], and NAFLD. Methods We used PubMed and EMBASE databases to identify all studies that assessed the association between vitamin D and NAFLD up until 22 April 2013, without language restrictions. We included studies that compared vitamin D levels between NAFLD cases and controls and also those that compared the odds of vitamin D deficiency by NAFLD status. Pooled standardised differences and odds ratios were calculated using an inverse variance method. Results Seventeen cross-sectional and case–control studies have evaluated the association between vitamin D and NAFLD. NAFLD was diagnosed using biopsy (4 studies), ultrasound or CT (10 studies) and liver enzymes (3 studies). Nine studies provided data for a quantitative meta-analysis. Compared to controls, NAFLD patients had 0.36 ng/mL (95% CI: 0.32, 0.40 ng/mL) lower levels of 25(OH)D and were 1.26 times more likely to be vitamin D deficient (OR 1.26, 95% CI: 1.17, 1.35). Conclusions NAFLD patients have decreased serum 25(OH)D concentrations, suggesting that vitamin D may play a role in the development of NAFLD. The directionality of this association cannot be determined from cross-sectional studies. Demonstration of a causal role of hypovitaminosis D in NAFLD development in future studies could have important therapeutic implications.

Publisher Summary The cyclical hormonal changes that occur in women are often a reason to exclude females from clinical and basic research studies. However, these very hormones may play a role in the pathogenesis of diseases in women. For this reason, it is important to consider gender when evaluating a patient. In hepatology, gender and sex hormones play a role in the epidemiology of autoimmune diseases (autoimmune hepatitis and primary biliary cirrhosis), the effect of alcohol on the liver, the development of benign and malignant liver tumors, and of course on pregnancy-related liver diseases. This chapter discusses the impact of female gender on the development and/or progression of specific liver diseases. Liver diseases that may coincide with, but are unrelated to, pregnancy usually do not result in significant maternal or fetal mortality. However, in the case of pregnancy-specific liver disease, it is essential to accurately determine the gestational age, and the timing of the disease onset. Liver diseases unique to pregnancy include ovarian hyperstimulation syndrome (OHSS), hyperemesis gravidarum (HG), intrahepatic cholestasis of pregnancy (ICP), acute fatty liver of pregnancy (AFLP), hemolysis–elevated liver enzymes–low platelets (HELLP) syndrome, and hepatic hemorrhage or rupture. OHSS is a potentially fatal iatrogenic complication associated with ovulation-induction therapy. The basic pathophysiologic hallmark of OHSS is an increase in capillary permeability that results in the leakage or exudation of protein-rich fluid from the ovaries or peritoneal surface to the third space compartments.

Liver fibrosis is a progressive pathologic process that involves deposition of excess extracellular matrix leading to distorted architecture and culminating in cirrhosis. The role of transforming growth factor-beta (TGF-beta) as a key molecule in the development and progression of hepatic fibrosis via the activation of hepatic stellate cells, among other fibroblast populations, is without controversy. We hereby show that TGF-beta1 induces an epithelial-to-mesenchymal transition (EMT) state in mature hepatocytes in vitro. EMT state was marked by significant upregulation of alpha(1)(I) collagen mRNA expression and type I collagen deposition. Similar changes were found in a "normal" mouse hepatocyte cell line (AML12), thus confirming that hepatocytes are capable of EMT changes and type I collagen synthesis. We also show that in hepatocytes in the EMT state, TGF-beta1 induces the snail-1 transcription factor and activates the Smad2/3 pathway. Evidence for a central role of the TGF-beta1/Smad pathway is further supported by the inhibition of EMT by Smad4 silencing using small interference RNA technology. In conclusion, TGF-beta1, a known pro-apoptotic cytokine in mature hepatocytes, is capable of mediating phenotypic changes and plasticity in the form of EMT, resulting in collagen deposition. Our findings support a potentially crucial role for EMT in the development and progression of hepatic fibrogenesis.

Interferon beta (IFNβ) treatment in multiple sclerosis (MS) has been associated with hepatotoxicity,1 and there have been reported cases of severe hepatitis induced by IFNβ.2,3 Acute autoimmune hepatitis (AIH) as a side effect of IFNβ therapy in MS is rare.2–4 There are no reported cases of IFNβ unmasking previously undiagnosed chronic AIH. We report a case in which chronic AIH only became symptomatic and diagnosed following the initiation of IFNβ therapy, and early recognition resulted in definitive therapy and an excellent outcome. A 43-year-old woman recently diagnosed with MS was started on IFNβ1a (Rebif) 22 μg TIW, and the dose was increased to 44 μg over 1 month as per routine protocol. She did not have any history of liver disease, alcohol abuse, or illicit drug use, and liver function tests (LFTs) were normal prior to treatment. Despite being told to have liver function tests performed 1 month after initiation of IFNβ, she was not heard from until about 6 weeks after the …

Hepatic steatosis may have a generally benign prognosis, either because most hepatocytes are not significantly injured or mechanisms to replace damaged hepatocytes are induced. To determine the relative importance of these mechanisms, we compared hepatocyte damage and replication in ethanol-fed and ob/ob mice with very indolent fatty liver disease to that of healthy control mice and PARP-1-/- mice with targeted disruption of the DNA repair enzyme, poly(ADP-ribose) polymerase. Compared to the healthy controls, both groups with fatty livers had significantly higher serum alanine aminotransferase values, hepatic mitochondrial H2O2 production, and hepatocyte oxidative DNA damage. A significantly smaller proportion of the hepatocytes from fatty livers entered S phase when cultured with mitogens. Moreover, this replicative senescence was not reversed by treating cultured hepatocytes with agents (i.e., betaine or leptin) that improve liver disease in intact ethanol-fed or leptin-deficient mice. Hepatocytes from PARP1-/- mice also had more DNA damage and reduced DNA synthesis in response to mitogens. However, neither mice with fatty livers nor PARP-1-deficient mice had atrophic livers. All of the mice with senescent mature hepatocytes exhibited hepatic accumulation of liver progenitor (oval) cells and oval cell numbers increased with the demand for hepatocyte replacement. Therefore, although hepatic oxidant production and damage are generally increased in fatty livers, expansion of hepatic progenitor cell populations helps to compensate for the increased turnover of damaged mature hepatocytes. In conclusion, these results demonstrate that induction of mechanisms to replace damaged hepatocytes is important for limiting the progression of fatty liver disease. (HEPATOLOGY 2004;39:403–411.)

Background Doses of ethanol (EtOH) that are not overtly cytotoxic inhibit mitogen-induced hepatocyte proliferation and delay liver regeneration after 70% partial hepatectomy (PH). The mechanisms for this are poorly understood. This study evaluates the hypothesis that EtOH inhibits hepatocyte proliferation after PH by inducing redox-sensitive factors, such as p38 mitogen-activated protein kinase (MAPK) and p21 (WAF1/CIP1), that protect cells from oxidative stress but prevent cell-cycle progression by inhibiting cyclin D1. Methods Mechanisms that regulate the transition from the prereplicative G1 phase of the cell cycle into S phase were compared in EtOH-fed mice and normal pair-fed mice after PH. Results Prior EtOH exposure significantly increases p38 MAPK and p21 after PH. This is accompanied by reduced expression of cyclin D1 messenger RNA and protein, increases in other cell-cycle regulators (such as signal transducer and activator of transcription-3 and p27) that are normally inhibited by cyclin D1, and hepatocyte G1 arrest. Conclusions EtOH amplifies G1 checkpoint mechanisms that are induced by oxidative stress and promotes hepatic accumulation of factors, including p38 MAPK, p21, and signal transducer and activator of transcription-3, that enhance cellular survival after oxidant exposure. Therefore, cell-cycle inhibition may be an adaptive response that helps EtOH-exposed livers survive situations, such as PH, that acutely increase reactive oxygen species in hepatocytes.

The lipid content of hepatocytes is regulated by the integrated activities of cellular enzymes that catalyze lipid uptake, synthesis, oxidation, and export. When "input" of fats into these systems (either because of increased fatty acid delivery, hepatic fatty acid uptake, or fatty acid synthesis) exceeds the capacity for fatty acid oxidation or export (i.e., "output"), then hepatic steatosis occurs. Genetic causes of increased fatty acid input promote excessive hepatic lipogenesis. These include mutations that cause leptin deficiency or leptin receptor inhibition and mutations that induce insulin, insulin-like growth factors, or insulin-responsive transcription factors. Genetic causes of impaired hepatic fatty acid oxidation inhibit the elimination (i.e., output) of fat from the liver. These include mutations that inhibit various components of the peroxisomal and/or mitochondrial pathways for fatty acid beta-oxidation. Environmental factors, such as diets and toxins, can also unbalance hepatic fatty acid synthesis and oxidation. Hepatic lipogenesis is increased by dietary sucrose, fructose, or fats and certain toxins, such as ethanol. Hepatic fatty acid oxidation is inhibited by choline- or methionine-deficient diets and other toxins, such as etomoxir. Animals with genetic or environmental induction of hepatic lipogenesis appear to be useful models for human nonalcoholic fatty liver disease in which hyperinsulinemia and defective leptin signaling are conspicuous at early stages of the disease process.

The mechanisms that permit adult tissues to regenerate when injured are not well understood. Initiation of liver regeneration requires the injury-related cytokines, tumor necrosis factor (TNF) alpha and interleukin (IL) 6, and involves the activation of cytokine-regulated transcription factors such as NF-kappabeta and STAT3. During regeneration, TNFalpha and IL-6 promote hepatocyte viability, as well as proliferation, because interventions that inhibit either cytokine not only block hepatocyte DNA synthesis, but also increase liver cell death. These observations suggest that the cytokines induce hepatoprotective factors in the regenerating liver. Given evidence that nitric oxide can prevent TNF-mediated activation of the pro-apoptotic protease caspase 3 and protect hepatocytes from cytokine-mediated death, cytokine-inducible nitric oxide synthase (iNOS) may be an important hepatoprotective factor in the regenerating liver. In support of this hypothesis we report that the hepatocyte proliferative response to partial liver resection is severely inhibited in transgenic mice with targeted disruption of the iNOS gene. Instead, partial hepatectomy is followed by increased caspase 3 activity, hepatocyte death, and liver failure, despite preserved induction of TNFalpha, IL-6, NF-kappabeta, and STAT3. These results suggest that during successful tissue regeneration, injury-related cytokines induce factors, such as iNOS and its product, NO, that protect surviving cells from cytokine-mediated death.