Browsing by Author "Liangpunsakul, Suthat"
Now showing 1 - 10 of 86
Results Per Page
Sort Options
Item Activin B Promotes Hepatic Fibrogenesis(2019-08) Wang, Yan; Dai, Guoli; Berbari, Nicolas; Yaden, Benjamin; Liangpunsakul, Suthat; Skalnik, David G.Liver fibrosis is a common consequence of various chronic liver diseases. Although transforming growth factor β 1 (TGFβ1) expression is known to be associated with liver fibrosis, the reduced clinical efficacy of TGFβ1 inhibition or the inefficiency to completely prevent liver fibrosis in mice with liver-specific knockout of TGF receptor II suggests that other factors can mediate liver fibrogenesis. As a TGFβ superfamily ligand, activin A signaling modulates liver injury by prohibiting hepatocyte proliferation, mediating hepatocyte apoptosis, promoting Kupffer cell activation, and inducing hepatic stellate cell (HSC) activation in vitro. However, the mechanism of action and in vivo functional significance of activin A in liver fibrosis models remain uncertain. Moreover, whether activin B, another ligand structurally related to activin A, is involved in liver fibrogenesis is not yet known. This study aimed to investigate the role of activin A and B in liver fibrosis initiation and progression. The levels of hepatic and circulating activin B and A were analyzed in patients with various chronic liver diseases, including end-stage liver diseases (ESLD), non-alcoholic steatohepatitis (NASH), and alcoholic liver disease (ALD). In addition, their levels were measured in mouse carbon tetrachloride (CCl4), bile duct ligation (BDL), and ALD liver injury models. Mouse primary hepatocytes, RAW264.7 cells, and LX-2 cells were used as in vitro models of hepatocytes, macrophages, and HSCs, respectively. The specificity and potency of anti-activin B monoclonal antibody (mAb) and anti-activin A mAb were evaluated using Smad2/3 luciferase assay. Activin A, activin B, or their combination were immunologically inactivated by the neutralizing mAbs in mice with progressive or established liver fibrosis induced by CCl4 or with developing cholestatic liver fibrosis induced by BDL surgery. In patients with ESLD, NASH, and ALD, increases in hepatic and circulating activin B, but not activin A, were associated with liver fibrosis, irrespective of etiology. In mice with CCl4-, BDL-, or alcohol-induced liver injury, activin B was persistently elevated in the liver and circulation, whereas activin A showed only transient increases. Activin B was expressed and secreted mainly by the hepatocytes and other cells, including cholangiocytes, activated HSCs, and immune cells. Exogenous administration of activin B promoted hepatocyte injury, activated macrophages to release cytokines, and induced a pro-fibrotic expression profile and septa formation in HSCs. Co-treatment of activin A and B interdependently activated the chemokine (C-X-C motif) ligand 1 (CXCL1)/inducible nitric oxide synthase (iNOS) pathway in macrophages and additively upregulated connective tissue growth factor expression in HSCs. Activin B and A had redundant, unique, and interactive effects on the transcripts related to HSC activation. The neutralization of activin B attenuated the development of liver fibrosis and improved liver function in mice with CCl4- or BDL-induced liver fibrosis and largely reversed the already established liver fibrosis in the CCl4 mouse model. These effects were improved by the administration of additional anti-activin A antibody. Combination of both antibodies also inhibited hepatic and circulating inflammatory cytokine production in the BDL mouse model. In conclusion, activin B is a potential circulating biomarker and potent promotor of liver fibrosis. Its levels in the liver and circulation increase significantly in both acute and chronic states of liver injury. Activin B might additively or interdependently cooperate with activin A, which directly acts on multiple liver cell populations during liver injury and fibrosis, as the combination of both proteins increases pro-inflammatory and pro-fibrotic responses in vitro. In addition, the neutralization of both activin A and activin B in vivo enhances the preventive and reversible effects of liver injury and fibrosis compared to that when activin B alone is neutralized. Our data reveal a novel target of liver fibrosis and the mechanism of activin B-mediated initiation of this process by damaging hepatocytes and activating macrophages and HSCs. Our findings show that activin B promotes hepatic fibrogenesis, and that targeting of activin B has anti-inflammatory and anti-fibrotic effects, which ameliorate liver injury by preventing or regressing liver fibrosis. Antagonizing either activin B alone or in combination with activin A prevents and regresses liver fibrosis in multiple animal studies, paving way for future clinical studies.Item Acute Alcoholic Hepatitis: Natural History and Predictors of Mortality Using a Multicenter Prospective Study(Elsevier, 2017-04-28) Lourens, Spencer; Sunjaya, Dharma B.; Singal, Ashwani; Liangpunsakul, Suthat; Puri, Puneet; Sanyal, Arun; Ren, Xiaowei; Gores, Gregory J.; Radaeva, Svetlana; Chalasani, Naga; Crabb, David W.; Katz, Barry; Kamath, Patrick S.; Shah, Vijay H.; Biostatistics, School of Public HealthObjective: To examine the natural history of acute alcoholic hepatitis (AH) and identify predictors of mortality for AH using data from a prospective multicenter observational study. Participants and Methods: We analyzed data from 164 patients with AH and 131 heavy-drinking controls with no liver disease. Participants underwent clinical/laboratory assessment at baseline and 6 and 12 months after enrollment. Multivariable analyses were conducted to identify variables associated with mortality and examine the association between coffee drinking and risk of AH. Results: Thirty-six patients with AH died during follow-up, with estimated 30-day, 90-day, 180-day, and 1-year survival of 0.91 (95% CI, 0.87-0.96), 0.85 (95% CI, 0.80-0.91), 0.80 (95% CI, 0.74-0.87), and 0.75 (95% CI, 0.68-0.83), respectively. In the multivariable analysis, higher serum bilirubin level (hazard ratio [HR]=1.059; 95% CI, 1.022-1.089), lower hemoglobin level (HR=1.263; 95% CI, 1.012-1.575), and lower platelet count (HR=1.006; 95% CI, 1.001-1.012) were independently associated with mortality in AH. Compared with controls, fewer patients with AH regularly consumed coffee (20% vs 44%; P<.001), and this association between regular coffee drinking and lower risk of AH persisted after controlling for relevant covariates (odds ratio=0.26; 95% CI, 0.15-0.46). Time-dependent receiver operating characteristic curve analysis revealed that Model for End-Stage Liver Disease; Maddrey Discriminant Function; age, serum bilirubin, international normalized ratio, and serum creatinine; and Child-Pugh scores all provided similar discrimination performance at 30 days (area under the curve=0.73-0.77). Conclusion: Alcoholic hepatitis remains highly fatal, with 1-year mortality of 25%. Regular coffee consumption was associated with lower risk of AH in heavy drinkers.Item Adult Diffuse Hepatic Hemangiomatosis: A Rare Cause of Dilated Cardiomyopathy and Sudden Cardiac Arrest(Springer, Part of Springer Science+Business Media, 2014-01) Supakul, Rodjawan; Vakili, Saeed T.; Liangpunsakul, Suthat; Department of Medicine, IU School of MedicineItem Advanced endoscopic ultrasound management techniques for preneoplastic pancreatic cystic lesions(BMJ, 2017-01) Arshad, Hafiz Muhammad Sharjeel; Bharmal, Sheila; Duman, Deniz Guney; Liangpunsakul, Suthat; Turner, Brian G.; Department of Medicine, IU School of MedicinePancreatic cystic lesions can be benign, premalignant or malignant. The recent increase in detection and tremendous clinical variability of pancreatic cysts has presented a significant therapeutic challenge to physicians. Mucinous cystic neoplasms are of particular interest given their known malignant potential. This review article provides a brief but comprehensive review of premalignant pancreatic cystic lesions with advanced endoscopic ultrasound (EUS) management approaches. A comprehensive literature search was performed using PubMed, Cochrane, OVID and EMBASE databases. Preneoplastic pancreatic cystic lesions include mucinous cystadenoma and intraductal papillary mucinous neoplasm. The 2012 International Sendai Guidelines guide physicians in their management of pancreatic cystic lesions. Some of the advanced EUS management techniques include ethanol ablation, chemotherapeutic (paclitaxel) ablation, radiofrequency ablation and cryotherapy. In future, EUS-guided injections of drug-eluting beads and neodymium:yttrium aluminum agent laser ablation is predicted to be an integral part of EUS-guided management techniques. In summary, International Sendai Consensus Guidelines should be used to make a decision regarding management of pancreatic cystic lesions. Advanced EUS techniques are proving extremely beneficial in management, especially in those patients who are at high surgical risk.Item Alcohol abstinence ameliorates the dysregulated immune profiles in patients with alcoholic hepatitis: A prospective observational study(Wiley, 2017) Li, Wei; Amet, Tohti; Xing, Yanyan; Yang, Dennis; Liangpunsakul, Suthat; Puri, Puneet; Kamath, Patrick; Sanyal, Arun; Shah, Vijay; Katz, Barry; Radaeva, Svetlana; Crabb, David; Chalasani, Naga; Yu, Qigui; Department of Microbiology and Immunology, IU School of MedicineAlcoholic hepatitis (AH) develops in only a small proportion of heavy drinkers. To better understand the mechanisms underlying this disparity, we conducted a study to define the relationship between AH development and dysregulated immune responses that might be ameliorated by alcohol abstinence. Sixty-eight AH patients, 65 heavy drinking controls without liver disease (HDC), and 20 healthy controls were enrolled and followed up to 12 months. At baseline, HDC and healthy controls had no significant differences in their plasma levels of 38 inflammatory cytokines/chemokines measured using multiplex immunoassays. However, compared to HDC, AH patients had higher baseline levels of 11 cytokines/chemokines (tumor necrosis factor alpha, interleukin 6 [IL-6], IL-8, interferon gamma–induced protein 10, IL-4, IL-9, IL-10, fibroblast growth factor 2, IL-7, IL-15, and transforming growth factor alpha) but lower levels of the anti-inflammatory macrophage-derived chemokine. AH patients also had more activated yet dysfunctional immune cells as monocytes, T cells, and B cells expressed higher levels of cluster of differentiation 38 (CD38) and CD69 but low levels of human leukocyte antigen DR, CD80, and CD86 at baseline. In addition, CD4 T cells produced less interferon-gamma in response to T-cell stimulation. Up-regulated IL-6, IL-8, CD38, and CD69 and down-regulated macrophage-derived chemokine, human leukocyte antigen DR, CD86, and CD80 correlated positively and negatively, respectively, with disease severity. Longitudinal analysis indicated that levels of IL-6, IL-8, CD38, and CD69 were reduced, whereas levels of macrophage-derived chemokine, human leukocyte antigen DR, CD80, and CD86 were increased in abstinent AH patients. All of the cellular immune abnormalities were reversed by day 360 in abstinent AH patients; however, plasma levels of tumor necrosis factor alpha, IL-8, IL-10, fibroblast growth factor 2, and IL-7 remained higher. Conclusion: AH patients were in a highly immune-dysregulated state, whereas HDC showed little evidence of immune activation; alcohol abstinence reversed most, but not all, of the immunological abnormalities.Item Alcohol Abstinence Does Not Fully Reverse Abnormalities of Mucosal-Associated Invariant T Cells in the Blood of Patients With Alcoholic Hepatitis(Wolters Kluwer, 2019-06) Li, Wei; Lin, Edward L.; Liangpunsakul, Suthat; Lan, Jie; Chalasani, Sai; Rane, Sushmita; Puri, Puneet; Kamath, Patrick S.; Sanyal, Arun J.; Shah, Vijay H.; Radaeva, Svetlana; Crabb, David W.; Chalasani, Naga; Yu, Qigui; Microbiology & Immunology, IU School of MedicineOBJECTIVES: Alcoholic hepatitis (AH) develops in approximately 30% of chronic heavy drinkers. The immune system of patients with AH is hyperactivated, yet ineffective against infectious diseases. Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that are highly enriched in liver, mucosa, and peripheral blood and contribute to antimicrobial immunity. We aimed to determine whether MAIT cells were dysregulated in heavy drinkers with and without AH and the effects of alcohol abstinence on MAIT cell recovery. METHODS: MR1 tetramers loaded with a potent MAIT cell ligand 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil were used in multiparameter flow cytometry to analyze peripheral blood MAIT cells in 59 healthy controls (HC), 56 patients with AH, and 45 heavy drinkers without overt liver disease (HDC) at baseline and 6- and 12-month follow-ups. Multiplex immunoassays were used to quantify plasma levels of cytokines related to MAIT cell activation. Kinetic Turbidimetric Limulus Amebocyte Lysate Assay and ELISA were performed to measure circulating levels of 2 surrogate markers for bacterial translocation (lipopolysaccharide and CD14), respectively. RESULTS: At baseline, patients with AH had a significantly lower frequency of MAIT cells than HDC and HC. HDC also had less MAIT cells than HC (median 0.16% in AH, 0.56% in HDC, and 1.25% in HC). Further, the residual MAIT cells in patients with AH expressed higher levels of activation markers (CD69, CD38, and human leukocyte antigen [HLA]-DR), the effector molecule granzyme B, and the immune exhaustion molecule PD-1. Plasma levels of lipopolysaccharide and CD14 and several cytokines related to MAIT cell activation were elevated in patients with AH (interferon [IFN]-α, interleukin [IL]-7, IL-15, IL-17, IL-18, IL-23, IFN-γ, and tumor necrosis factor α). Decreased MAIT cell frequency and upregulated CD38, CD69, and HLA-DR correlated negatively and positively, respectively, with aspartate aminotransferase level. MAIT cell frequency negatively correlated with IL-18. HLA-DR and CD38 levels correlated with several cytokines. At follow-ups, abstinent patients with AH had increased MAIT cell frequency and decreased MAIT cell activation. However, MAIT cell frequency was not fully normalized in patients with AH (median 0.31%). DISCUSSION: We showed that HDC had a reduction of blood MAIT cells despite showing little evidence of immune activation, whereas patients with AH had a severe depletion of blood MAIT cells and the residual cells were highly activated. Alcohol abstinence partially reversed those abnormalities.Item Alcohol and fat promote steatohepatitis: a critical role for fat-specific protein 27/CIDEC(BMJ Journals, 2016-08) Liangpunsakul, Suthat; Gao, Bin; Medicine, School of MedicineAlcoholic liver disease (ALD) is a major public health problem worldwide and is the leading cause of end-stage liver disease. While the ultimate control of ALD will require the prevention of alcohol abuse, better understanding of the mechanisms of alcohol-induced liver injury may lead to treatments of fatty liver, alcoholic hepatitis, and prevention or delay of occurrence of cirrhosis. The elucidation and the discovery of several new concepts in ALD pathogenesis have raised our understanding on the complex mechanisms and the potential in developing the new strategies for therapeutic benefits. In this review, we provide the most up-to-date information on the basic molecular mechanisms focusing on the role of fat-specific protein 27/CIDEC in the pathogenesis of ALD.Item Alcohol Metabolizing Enzymes, Microsomal Ethanol Oxidizing System, Cytochrome P450 2E1, Catalase, and Aldehyde Dehydrogenase in Alcohol-Associated Liver Disease(MDPI, 2020-03) Jiang, Yanchao; Zhang, Ting; Kusumanchi, Praveen; Han, Sen; Yang, Zhihong; Liangpunsakul, Suthat; Medicine, School of MedicineOnce ingested, most of the alcohol is metabolized in the liver by alcohol dehydrogenase to acetaldehyde. Two additional pathways of acetaldehyde generation are by microsomal ethanol oxidizing system (cytochrome P450 2E1) and catalase. Acetaldehyde can form adducts which can interfere with cellular function, leading to alcohol-induced liver injury. The variants of alcohol metabolizing genes encode enzymes with varied kinetic properties and result in the different rate of alcohol elimination and acetaldehyde generation. Allelic variants of these genes with higher enzymatic activity are believed to be able to modify susceptibility to alcohol-induced liver injury; however, the human studies on the association of these variants and alcohol-associated liver disease are inconclusive. In addition to acetaldehyde, the shift in the redox state during alcohol elimination may also link to other pathways resulting in activation of downstream signaling leading to liver injury.Item Alcohol Rehabilitation Within 30 Days of Hospital Discharge Is Associated With Reduced Readmission, Relapse, and Death in Patients With Alcoholic Hepatitis(Elsevier, 2019) Peeraphatdit, Thoetchai (Bee); Kamath, Patrick S.; Karpyak, Victor M.; Davis, Brian; Desai, Vivek; Liangpunsakul, Suthat; Sanyal, Arun; Chalasani, Naga; Shah, Vijay H.; Simonetto, Douglas A.; Medicine, School of MedicineBackground & Aims Patients admitted to the hospital for alcoholic hepatitis (AH) are at increased risk of readmission and death. We aimed to identify factors associated with readmission, alcohol relapse, and mortality. Methods We performed a retrospective analysis of consecutive patients admitted with AH to a tertiary care hospital from 1999 through 2016 (test cohort, n = 135). We validated our findings in a prospective analysis of patients in a multi-center AH research consortium from 2013 through 2017 (validation cohort, n = 159). Alcohol relapse was defined as any amount of alcohol consumption within 30 days after hospital discharge. Early alcohol rehabilitation was defined as residential or outpatient addiction treatment or mutual support group participation within 30 days after hospital discharge. Results Thirty-day readmission rates were 30% in both cohorts. Alcohol relapse rates were 37% in the test and 34% in the validation cohort. Following hospital discharge, 27 patients (20%) in the test cohort and 19 patients (16%) in the validation cohort attended early alcohol rehabilitation. There were 53 deaths (39%) in a median follow-up time of 2.8 years and 42 deaths (26%) in a median follow-up time of 1.3 years, respectively. In the test cohort, early alcohol rehabilitation reduced odds for 30-day readmission (adjusted odds ratios [AOR] 0.16; 95% CI, 0.04–0.65; P = .01), 30-day alcohol relapse (AOR, 0.11; 95% CI, 0.02–0.53; P < .001), and death (adjusted hazard ratio [AHR], 0.20; 95% CI, 0.05–0.56; P = .001). In the validation cohort early alcohol rehabilitation reduced odds for 30-day readmission (AOR, 0.30; 95% CI, 0.09–0.98; P = .04), 30-day alcohol relapse (AOR 0.09; 95% CI, 0.01–0.73; P = .02), and death (AHR, 0.20; 95% CI, 0.01–0.94; P = .04). A model combining alcohol rehabilitation and bilirubin identified patients with readmission to the hospital within 30 days with an area under the receiver operating characteristic curve of 0.73. Conclusions In an analysis from two cohorts of patients admitted with AH, early alcohol rehabilitation can reduce risk of hospital readmission, alcohol relapse, and death and should be considered as a quality indicator in AH hospitalization treatment.Item Alcoholic Liver Disease in Asia, Europe, and North America(Elsevier, 2016-06) Liangpunsakul, Suthat; Haber, Paul; McCaughan, Geoffrey W.; Medicine, School of MedicineAlcoholic liver diseases comprise a spectrum of clinical disorders and changes in liver tissue that can be detected by pathology analysis. These range from steatosis to more severe signs and symptoms of liver disease associated with inflammation, such as those observed in patients with alcoholic hepatitis or cirrhosis. Although the relationship between alcohol consumption and liver disease is well established, severe alcohol-related morbidities develop in only a minority of people who consume alcohol in excess. Inter-individual differences in susceptibility to the toxic effects of alcohol have been studied extensively-they include pattern of alcohol consumption, sex, environmental factors (such as diet), and genetic factors, which vary widely among different parts of the world. Alcoholic liver disease is becoming more common in many parts of Asia, but is decreasing in Western Europe. Treatment approaches, including availability of medications, models of care, and approach to transplantation, differ among regions.