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Abstract
Non-alcoholic fatty liver disease (NAFLD) refers to the accumulation of hepatic steatosis not due to excess alcohol consumption. The prevalence of NAFLD is up to 30% in developed countries and nearly 10% in developing nations, making NAFLD the most common liver condition in the world. The pathogenesis of NAFLD is related to insulin resistance and, thus, it is frequently found in individuals who have central obesity or diabetes. Insulin resistance and excess adiposity are associated with increased lipid influx into the liver and increased de novo hepatic lipogenesis, promoting hepatic triglyceride accumulation. Defects in lipid utilization via mitochondrial oxidation and lipid export may also contribute to hepatic lipid build-up. Adipocytokine alterations, lipotoxicity from saturated fatty acids and fructose have been all been implicated in causing hepatocyte injury in NAFLD through pathways involving oxidative and endoplasmic reticulum stress. Clinically, NAFLD is commonly asymptomatic and frequently detected incidentally by blood liver function tests or imaging performed for other reasons. Subjects with NAFLD have a higher mortality rate than the general population and are at increased risk of developing cardiovascular disease and diabetes in the future. Histologically, NAFLD occurs as a spectrum from mild hepatic steatosis only, to non-alcoholic steatohepatitis (NASH) characterized by hepatocellular injury and inflammation, to cirrhosis. A diagnosis of NASH with associated fibrosis heralds a more significant prognosis as it is more likely to progressive to cirrhosis with complications of hepatic failure and hepatocellular carcinoma. Currently, the diagnosis of NASH requires a liver biopsy, however, serum based markers of hepatocyte apoptosis such as cytokeratin-18 fragments offer promise as accurate non-invasive diagnostic tests. Treatment of NAFLD revolves around addressing concomitant metabolic risk factors and improving insulin resistance through weight loss measures and exercise. Insulin sensitizing agents such as pioglitazone and anti-oxidant agents such as vitamin E show some promise in improving liver histology in patients with NASH, however, the long-term benefit of these medications has not been demonstrated.
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Affiliation(s)
- Briohny W Smith
- School of Medicine and Pharmacology, Sir Charles Gairdner Hospital Unit, University of Western Australia, Nedlands, Australia
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302
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Ciupińska-Kajor M, Hartleb M, Kajor M, Kukla M, Wyleżoł M, Lange D, Liszka L. Hepatic angiogenesis and fibrosis are common features in morbidly obese patients. Hepatol Int 2011; 7:233-40. [PMID: 23519653 PMCID: PMC3601246 DOI: 10.1007/s12072-011-9320-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 11/10/2011] [Indexed: 02/08/2023]
Abstract
Background A mass of visceral adipose tissue is one of the most important determinants of progressive liver injury in nonalcoholic fatty liver disease (NAFLD). In accordance, nonalcoholic steatohepatitis (NASH) and fibrosis are believed to occur more commonly in morbidly obese patients compared with nonobese NAFLD patients. Aim of the study Comparative analysis of NAFLD histopathologic features and angiogenesis activity in morbidly obese and nonobese subjects. Materials and methods Biopsy samples from 40 severely obese (BMI ≥40 kg m−2) and 30 nonobese (BMI ≤30 kg m−2) NAFLD patients were examined. Kleiner’s classification was used to diagnose NASH by grading steatosis, cytoplasmatic ballooning of hepatocytes, and lobular inflammation. The severity of fibrosis was evaluated according to the liver fibrosis staging system. Qualitative and quantitative immunohistochemical analyses of VEGF A, Flk-1, and CD34 were performed to study angiogenesis and the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) method was used to study hepatocyte apoptosis. Results Severely obese patients did not differ from nonobese patients with respect to age and sex distribution. NASH was diagnosed in nine (22.5%) severely obese patients and in seven (23.3%) nonobese patients. Fibrosis was more common in morbidly obese patients (82.5 vs. 43.5%, χ² = 11.71, p = 0.003) and was not associated with NASH. Moreover, the severity of fibrosis was greater in obese patients, as advanced fibrosis (bridging fibrosis and cirrhosis) occurred in six (15%) severely obese patients and in two (6.7%) nonobese patients. In morbidly obese individuals, angiogenesis was independent of NASH and was activated at the stage of simple steatosis. In severe obesity, there was a positive relationship between the stage of fibrosis and angiogenic activity. Conclusion In severely obese patients, fibrosis is probably promoted by mechanisms independent of NASH. In these patients, angiogenesis is activated early in the natural history of NAFLD and correlates with the severity of fibrosis.
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303
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Dowman JK, Armstrong MJ, Tomlinson JW, Newsome PN. Current therapeutic strategies in non-alcoholic fatty liver disease. Diabetes Obes Metab 2011; 13:692-702. [PMID: 21449949 DOI: 10.1111/j.1463-1326.2011.01403.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of disease ranging from simple steatosis through steatohepatitis (NASH) to increasing fibrosis and eventual cirrhosis. NAFLD is the hepatic manifestation of the metabolic syndrome and has now become the most common cause of liver disease in Western countries, with the more advanced stages of disease being associated with an increased risk of liver-related morbidity and mortality. The optimal management of patients with NAFLD remains a clinical challenge. The aim of this study is to describe established and emerging strategies for the treatment of NAFLD. Relevant research and review articles were identified by searching PubMed. Selected articles referenced in these publications were also examined. Good quality randomized controlled studies have demonstrated the need for multifaceted lifestyle interventions in patients with NAFLD including the need for diet, exercise and behavioural counselling. Despite several trials of pharmacological agents, no highly effective treatment yet exists, with surgery representing the mainstay for advanced disease. A multidisciplinary approach, with a major focus on lifestyle change, represents best treatment pending the development of new therapeutic options.
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Affiliation(s)
- J K Dowman
- Centre for Liver Research, Institute of Biomedical Research, University of Birmingham, Edgbaston, Birmingham, UK.
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304
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O'Leary JG, Landaverde C, Jennings L, Goldstein RM, Davis GL. Patients with NASH and cryptogenic cirrhosis are less likely than those with hepatitis C to receive liver transplants. Clin Gastroenterol Hepatol 2011; 9:700-704.e1. [PMID: 21570483 PMCID: PMC4408909 DOI: 10.1016/j.cgh.2011.04.007] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 03/30/2011] [Accepted: 04/05/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Many patients with cryptogenic cirrhosis (CC) have other conditions associated with nonalcoholic steatohepatitis (NASH) that put them at risk for complications that preclude orthotopic liver transplantation (OLT). METHODS We followed all patients with NASH and CC who were evaluated for OLT (n = 218) at Baylor Simmons Transplant Institute between March 2002 and May 2008. Data were compared with those from patients evaluated for OLT because of hepatitis C virus (HCV)-associated cirrhosis (n = 646). RESULTS Patients with NASH and CC were older, more likely to be female, had a higher body mass index, and a greater prevalence of diabetes and hypertension, compared with patients with HCV-associated cirrhosis, but the 2 groups had similar model for end-stage liver disease (MELD) scores. NASH and CC in patients with MELD scores ≤15 were less likely to progress; these patients were less likely to receive OLT and more likely to die or be taken off the wait list because they were too sick, compared with patients with HCV-associated cirrhosis. The median progression rate among patients with NASH and CC was 1.3 MELD points per year versus 3.2 MELD points per year for the HCV group (P = .003). Among patients with MELD scores >15, there were no differences among groups in percentage that received transplants or rate of MELD score progression. Hepatocellular carcinoma occurred in 2.7% of patients with NASH and CC per year, compared with 4.7% per year among those with HCV-associated cirrhosis. CONCLUSIONS Patients with NASH and CC and low MELD scores have slower disease progression than patients with HCV-associated cirrhosis and are less likely to receive OLT.
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Affiliation(s)
- Jacqueline G O'Leary
- Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, Texas, USA.
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305
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Vernon G, Baranova A, Younossi ZM. Systematic review: the epidemiology and natural history of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis in adults. Aliment Pharmacol Ther 2011; 34:274-85. [PMID: 21623852 DOI: 10.1111/j.1365-2036.2011.04724.x] [Citation(s) in RCA: 2204] [Impact Index Per Article: 169.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease, and its worldwide prevalence continues to increase with the growing obesity epidemic. This study assesses the epidemiology of NAFLD in adults based on clinical literature published over the past 30 years. AIM To review epidemiology and natural history of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis in adults based on clinical literature published over the past 30 years. METHODS An in-depth search of PubMed (1980-2010) was based on five search terms: 'non-alcoholic fatty liver disease' OR 'non-alcoholic steatohepatitis' OR 'fatty liver' OR 'steatosis' AND 'incidence' [MeSH Terms] OR 'prevalence' [MeSH Terms] OR 'natural history'. Studies of paediatric cohorts were excluded. Articles were categorised by topic and summarised, noting generalisations concerning their content. RESULTS Four study categories included NAFLD incidence, prevalence, risk factors and natural history. Studies related to NAFLD prevalence and incidence indicate that the diagnosis is heterogeneous and relies on a variety of assessment tools, including liver biopsy, radiological tests such as ultrasonography, and blood testing such as liver enzymes. The prevalence of NAFLD is highest in populations with pre-existing metabolic conditions such as obesity and type II diabetes. Many studies investigating the natural history of NAFLD verify the progression from NASH to advanced fibrosis and hepatocellular carcinoma. CONCLUSIONS Non-alcoholic fatty liver disease is the most common cause of elevated liver enzymes. Within the NAFLD spectrum, only NASH progresses to cirrhosis and hepatocellular carcinoma. With the growing epidemic of obesity, the prevalence and impact of NAFLD continues to increase, making NASH potentially the most common cause of advanced liver disease in coming decades.
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Affiliation(s)
- G Vernon
- Department of Medicine, Center for Liver Diseases, Inova Fairfax Hospital, Falls Church, VA 22042, USA
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306
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Carazo A, León J, Casado J, Gila A, Delgado S, Martín A, Sanjuan L, Caballero T, Muñoz JA, Quiles R, Ruiz-Extremera A, Alcázar LM, Salmerón J. Hepatic expression of adiponectin receptors increases with non-alcoholic fatty liver disease progression in morbid obesity in correlation with glutathione peroxidase 1. Obes Surg 2011; 21:492-500. [PMID: 21240660 DOI: 10.1007/s11695-010-0353-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND The prevalence of non-alcoholic fatty liver disease (NAFLD) in obesity is very high. The role of adiponectin receptors in NAFLD progression remains still unclear. We speculate that changes in the hepatic expression levels of the two adiponectin receptors may be associated with the expression of oxidative stress-related genes. METHODS We studied 60 morbidly obese patients with NAFLD, who underwent liver biopsy at the time of bariatric surgery. We measured the hepatic messenger-RNA concentration of adiponectin receptors (ADIPOR1 and ADIPOR2), glutathione peroxidase 1 (GPx1), glutathione reductase (GRd) and inducible oxide nitric synthase. Additionally, biochemical parameters and oxidative stress markers were determined in blood samples. According to the Kleiner score, the patients were divided into two groups: group 1 (25 patients without steatohepatitis) and group 2 (25 patients with probable steatohepatitis and ten patients with steatohepatitis). RESULTS The messenger-RNA concentration of all genes analysed in the study was higher among the patients in group 2. However, no differences in blood oxidative stress markers were observed. Strong correlations were found among the expression levels of ADIPOR1, ADIPOR2 and GPx1. The multivariate analysis showed that the only independent variable associated with NAFLD progression was the increase in GPx1 expression levels. CONCLUSIONS NAFLD progression in morbid obesity is associated with increase in hepatic adiponectin receptor and oxidative stress-related genes. The linear correlations suggest that ADIPOR1, ADIPOR2 and GPx1 share key molecular factors in the regulation of the genetic expressions.
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Affiliation(s)
- Angel Carazo
- Research Unit, San Cecilio University Hospital, Av de Madrid s/n, 18012, Granada, Spain.
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307
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Serologic predictors of nonalcoholic steatohepatitis in a population undergoing bariatric surgery. Surg Obes Relat Dis 2011; 8:416-22. [PMID: 21865094 DOI: 10.1016/j.soard.2011.06.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 04/29/2011] [Accepted: 06/17/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Nonalcoholic steatohepatitis (NASH) is common in the morbidly obese. It is a condition that can lead to progressive fibrosis and cirrhosis. We determined the prevalence in a population undergoing bariatric surgery and evaluated the possible serologic predictors before the development of fibrosis. METHODS Liver biopsies were taken from 370 consecutive patients who were undergoing laparoscopic bariatric surgery. The clinical and biochemical parameters were then assessed for correlation with the histologic features of nonalcoholic steatohepatitis. RESULTS Of the 370 patients, 68 (18%) were found to have NASH. Increased insulin resistance, alanine transaminase, and total bilirubin were independently associated with the presence of NASH. The presence of ≥ 2 of the 3 provided the best combination of sensitivity (.71) and specificity (.71) for predicting NASH. CONCLUSION Increased insulin resistance, alanine transaminase, and total bilirubin are serologic predictors for the presence of NASH before the development of fibrosis.
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308
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Pan JJ, Qu HQ, Rentfro A, McCormick JB, Fisher-Hoch SP, Fallon MB. Prevalence of metabolic syndrome and risks of abnormal serum alanine aminotransferase in Hispanics: a population-based study. PLoS One 2011; 6:e21515. [PMID: 21720553 PMCID: PMC3123360 DOI: 10.1371/journal.pone.0021515] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Accepted: 06/02/2011] [Indexed: 12/27/2022] Open
Abstract
Aim Study the prevalence of metabolic syndrome (MS) and risk factors for and association with elevated alanine aminotransferase (ALT) as markers of hepatic injury in a large Hispanic health disparity cohort with high rates of obesity. Methods Analysis of data from a prospective cross-sectional population based study. From 2004-7, we randomly recruited 2000 community participants to the Cameron County Hispanic Cohort collecting extensive socioeconomic, clinical and laboratory data. We excluded 153 subjects due to critical missing data. Pearson chi-square tests and Student's t-tests were used for categorical and continuous variable analysis, respectively. Logistic regression analysis was performed to determine the risk factors for elevated ALT. Results The mean age of the cohort was 45 years and 67% were females. The majority of the cohort was either overweight (32.4%) or obese (50.7%). Almost half (43.7%) had MS and nearly one-third diabetes. Elevated ALT level was more prevalent in males than females. Obesity was a strong risk for abnormal ALT in both genders. Hypertriglyceridemia, hypercholesterolemia and young age were risks for elevated ALT in males only, whereas increased fasting plasma glucose was associated with elevated ALT in females only. Conclusion We identified high prevalence of MS and markers of liver injury in this large Mexican American cohort with gender differences in prevalence and risk factors, with younger males at greatest risk.
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Affiliation(s)
- Jen-Jung Pan
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, University of Texas Health Science Center at Houston, Houston, Texas, United States of America.
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309
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Day CP. Non-alcoholic fatty liver disease: a massive problem. CLINICAL MEDICINE (LONDON, ENGLAND) 2011. [PMID: 21526706 DOI: 10.7861/clinmedicine.11-2-1761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Christopher P Day
- Institute of Cellular Medicine, Faculty of Medical Sciences, Newcastle University.
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310
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Tamimi TIAR, Elgouhari HM, Alkhouri N, Yerian LM, Berk MP, Lopez R, Schauer PR, Zein NN, Feldstein AE. An apoptosis panel for nonalcoholic steatohepatitis diagnosis. J Hepatol 2011; 54:1224-9. [PMID: 21145805 PMCID: PMC3098936 DOI: 10.1016/j.jhep.2010.08.023] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 08/09/2010] [Accepted: 08/20/2010] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS The extrinsic death receptor-mediated pathway of apoptosis is involved in nonalcoholic steatohepatitis (NASH) development. Our aims were to create and validate a noninvasive prediction model for NASH diagnosis based on specific circulating markers of apoptosis. METHODS Our initial cohort consisted of 95 consecutive patients undergoing a liver biopsy for clinically suspected NASH. Blood was obtained from each patient at the time of liver biopsy. Plasma caspase 3 generated cytokeratin-18 fragments (CK-18), soluble Fas (sFas), and soluble Fas ligand (sFasL) were measured. Histology was assessed by an experienced hepatopathologist. The validation cohort consisted of 82 consecutive patients that underwent liver biopsy at the time of bariatric surgery. RESULTS Patients with NASH had significantly higher levels of CK-18 and sFas than patients in the "not NASH" group [median (25th, 75th percentile): 508 (280, 846) U/L versus 176 (131, 224) U/L (p<0.001), and 11.8 (7.8, 12.5) ng/ml versus 5.9 (4.8, 8.3) ng/ml (p<0.001), respectively]. A significant positive correlation was revealed between the apoptosis markers and liver histopathology independent of other metabolic factors. A prediction model was generated including CK-18 fragments and sFas levels that showed an AUC of 0.93 and 0.79 in the initial and validation cohorts, respectively. A cutoff value using this model predicted NASH with a sensitivity and specificity of 88% and 89%, respectively. CONCLUSIONS Quantification of circulating levels of two apoptotic markers accurately predicts the presence of NASH, supporting the potential usefulness of these markers in clinical practice for noninvasive diagnosis of NASH.
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Affiliation(s)
| | - Hesham M. Elgouhari
- Transplant Institute, Avera Center for Liver Disease, Sioux Falls, South Dakota, USA
| | - Naim Alkhouri
- Department of Pediatric Gastroenterology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Lisa M. Yerian
- Department of Anatomic Pathology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Michael P. Berk
- Department of Cell Biology, Cleveland Clinic, Cleveland, Ohio, USA
| | - Rocio Lopez
- Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, Ohio, USA
| | - Phillip R. Schauer
- Bariatric and Metabolic Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Nizar N. Zein
- Digestive Disease Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Ariel E. Feldstein
- Department of Pediatric Gastroenterology, Cleveland Clinic, Cleveland, Ohio, USA,Department of Cell Biology, Cleveland Clinic, Cleveland, Ohio, USA
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311
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Machado MV, Cortez-Pinto H. No need for a large belly to have NASH. J Hepatol 2011; 54:1090-3. [PMID: 21281684 DOI: 10.1016/j.jhep.2011.01.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2011] [Revised: 01/09/2011] [Accepted: 01/11/2011] [Indexed: 01/22/2023]
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312
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Merrell MD, Cherrington NJ. Drug metabolism alterations in nonalcoholic fatty liver disease. Drug Metab Rev 2011; 43:317-34. [PMID: 21612324 DOI: 10.3109/03602532.2011.577781] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Drug-metabolizing enzymes play a vital role in the elimination of the majority of therapeutic drugs. The major organ involved in drug metabolism is the liver. Chronic liver diseases have been identified as a potential source of significant interindividual variation in metabolism. Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the United States, affecting between 60 and 90 million Americans, yet the vast majority of NAFLD patients are undiagnosed. NAFLD encompasses a spectrum of pathologies, ranging from steatosis to nonalcoholic steatohepatitis and fibrosis. Numerous animal studies have investigated the effects of NAFLD on hepatic gene expression, observing significant alterations in mRNA, protein, and activity levels. Information on the effects of NAFLD in human patients is limited, though several significant investigations have recently been published. Significant alterations in the activity of drug-metabolizing enzymes may affect the clearance of therapeutic drugs, with the potential to result in adverse drug reactions. With the enormous prevalence of NAFLD, it is conceivable that every drug currently on the market is being given to patients with NAFLD. The current review is intended to present the results from both animal models and human patients, summarizing the observed alterations in the expression and activity of the phase I and II drug-metabolizing enzymes.
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Affiliation(s)
- Matthew D Merrell
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, USA
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313
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Abstract
Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) frequently coexist as they share the pathogenic abnormalities of excess adiposity and insulin resistance. Although type 1 diabetes mellitus (T1DM) is due to a relative lack of insulin, an increased prevalence of obesity and insulin resistance in this population means that NAFLD also commonly coexists with this condition. Both T2DM and NAFLD are associated with adverse outcomes of the other; T2DM is a risk factor for progressive liver disease and liver-related death in patients with NAFLD, whereas NAFLD may be a marker of cardiovascular risk and mortality in individuals with T2DM. Nonalcoholic steatohepatitis-a histological subtype of NAFLD characterized by hepatocyte injury and inflammation-is present in approximately 10% of patients with T2DM and is associated with an increased risk for the development of cirrhosis and liver-related death. Current treatment strategies aim to improve insulin resistance via weight loss and exercise, improve insulin sensitivity by the use of insulin-sensitizing agents (for example, pioglitazone) and reduce oxidative stress by the use of antioxidants, such as vitamin E. Pioglitazone and vitamin E supplementation show the most promise in improving hepatic steatosis and inflammation but have not yet been demonstrated to improve fibrosis, and concern remains regarding the toxicity of long-term use of both of these agents.
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Affiliation(s)
- Briohny W Smith
- School of Medicine and Pharmacology, Sir Charles Gairdner Hospital Unit, University of Western Australia, Nedlands, WA 6009, Australia.
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314
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Bataller R, Rombouts K, Altamirano J, Marra F. Fibrosis in alcoholic and nonalcoholic steatohepatitis. Best Pract Res Clin Gastroenterol 2011; 25:231-44. [PMID: 21497741 DOI: 10.1016/j.bpg.2011.02.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2011] [Accepted: 02/18/2011] [Indexed: 01/31/2023]
Abstract
Both alcoholic and nonalcoholic steatohepatitis are relevant causes of cirrhosis and liver-related mortality. Alcohol abuse represents a major health problem in many countries, and liver disease is considered one of the most relevant causes of death related to this factor. Nonalcoholic fatty liver disease is the most common hepatic abnormality in the Western world, and progresses to cirrhosis and hepatocellular carcinoma in a significant portion of cases. Moreover, presence of NAFLD is associated with an increased risk of cardiovascular events. In this review, we discuss the characteristics of fibrosis in alcoholic and nonalcoholic steatohepatitis, focussing on the diagnostic issues and predictive factors. In addition, the pathogenetic mechanisms responsible for appearance and progression of fibrosis in the two conditions are briefly discussed.
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Affiliation(s)
- Ramon Bataller
- Liver Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and Centro de Investigación Biomèdica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Catalonia, Spain.
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315
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Baranova A, Tran TP, Birerdinc A, Younossi ZM. Systematic review: association of polycystic ovary syndrome with metabolic syndrome and non-alcoholic fatty liver disease. Aliment Pharmacol Ther 2011; 33:801-14. [PMID: 21251033 DOI: 10.1111/j.1365-2036.2011.04579.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Polycystic ovary syndrome (PCOS) is a common disorder for women of child-bearing age and is associated with metabolic syndrome (MS). AIM To assess the literature for associations between polycystic ovary syndrome and non-alcoholic fatty liver disease (NAFLD). METHODS We performed a systematic review using PubMed-search for peer-reviewed articles related to polycystic ovary syndrome and NAFLD. Articles were summarised and grouped according to different sections defining interactions of polycystic ovary syndrome with metabolic syndrome and non-alcoholic fatty liver disease as well as risk factors, pathogenic pathways and treatment options. RESULTS Obesity is a common factor involved in both polycystic ovary syndrome and non-alcoholic fatty liver disease. Obesity causes non-alcoholic fatty liver disease and aggravates hirsutism and menstrual disorders in polycystic ovary syndrome. Insulin resistance, a hallmark of metabolic syndrome is observed in 50-80% of women with polycystic ovary syndrome and patients with non-alcoholic fatty liver disease. Recent findings suggest that women with polycystic ovary syndrome may be at risk for developing non-alcoholic fatty liver disease and conversely, non-alcoholic fatty liver disease may be a risk for polycystic ovary syndrome. Based on the association of polycystic ovary syndrome and other metabolic abnormalities, such as insulin resistance, hyperandrogenism, obesity and non-alcoholic fatty liver disease, the candidate genes have been speculated for polycystic ovary syndrome. Closer scrutiny of these genes placed most of their proteins at the crossroads of three highly inter-related conditions: metabolic syndrome, obesity and non-alcoholic fatty liver disease. In most studies, the prevalence of both polycystic ovary syndrome and non-alcoholic fatty liver disease rises proportionally to the degree of insulin resistance and increases in the mass of adipose tissue. CONCLUSIONS Non-alcoholic fatty liver disease is considered as the hepatic manifestation of metabolic syndrome. Similarly, it seems appropriate to consider polycystic ovary syndrome as the ovarian manifestation of metabolic syndrome. Both these conditions can co-exist and may respond to similar therapeutic strategies.
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Affiliation(s)
- A Baranova
- Betty and Guy Beatty Center for Integrated Research, Inova Health System, 3300 Gallows Road, Falls Church, VA 22042, USA
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316
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Kant P, Hull MA. Excess body weight and obesity--the link with gastrointestinal and hepatobiliary cancer. Nat Rev Gastroenterol Hepatol 2011; 8:224-38. [PMID: 21386810 DOI: 10.1038/nrgastro.2011.23] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Excess body weight (EBW) is an independent risk factor for many human malignancies, including cancers throughout the gastrointestinal and hepatobiliary tract from the esophagus to the colorectum. The relative risk of gastrointestinal cancer in obese individuals is approximately 1.5-2.0 times that for normal weight individuals, with organ-specific and gender-specific differences for specific cancers. The association between EBW and risk of premalignant stages of gastrointestinal carcinogenesis, such as colorectal adenoma and Barrett esophagus, is similar, implying a role for EBW during the early stages of carcinogenesis that could be relevant to preventative strategies. EBW also impacts negatively on gastrointestinal cancer outcomes. The mechanistic basis of the association between EBW and carcinogenesis remains incompletely understood. Postulated mechanisms include increased insulin and insulin-like growth factor signaling and chronic inflammation (both linked to the metabolic syndrome), as well as signaling via adipokines, such as leptin. The role of obesity-related changes in the intestinal microbiome in gastrointestinal carcinogenesis deserves further attention. Whether weight loss leads to reduced future gastrointestinal and liver cancer risk has yet to be fully explored. There is some support for the idea that weight loss negatively regulates colorectal carcinogenesis. In addition, data suggest a reduction in risk of several cancers in the first 10 years after bariatric surgery.
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Affiliation(s)
- Prashant Kant
- Leeds Institute of Molecular Medicine, University of Leeds, St. James's University Hospital, Beckett Street, Leeds, UK
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317
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Affiliation(s)
- Christopher P Day
- Institute of Cellular Medicine, Faculty of Medical Sciences, Newcastle University.
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Dowman JK, Tomlinson JW, Newsome PN. Systematic review: the diagnosis and staging of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. Aliment Pharmacol Ther 2011; 33:525-40. [PMID: 21198708 PMCID: PMC3080668 DOI: 10.1111/j.1365-2036.2010.04556.x] [Citation(s) in RCA: 216] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 09/27/2010] [Accepted: 12/06/2010] [Indexed: 02/06/2023]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent cause of liver disease in Western countries. The development of non-alcoholic steatohepatitis (NASH) and fibrosis identifies an at-risk group with increased risk of cardiovascular and liver-related deaths. The identification and management of this at-risk group remains a clinical challenge. AIM To perform a systematic review of the established and emerging strategies for the diagnosis and staging of NAFLD. METHODS Relevant research and review articles were identified by searching PubMed, MEDLINE and EMBASE. RESULTS There has been a substantial development of non-invasive risk scores, biomarker panels and radiological modalities to identify at-risk patients with NAFLD without recourse to liver biopsy on a routine basis. These modalities and algorithms have improved significantly in their diagnosis and staging of fibrosis and NASH in patients with NAFLD, and will likely impact on the number of patients undergoing liver biopsy. CONCLUSIONS Staging for NAFLD can now be performed by a combination of radiological and laboratory techniques, greatly reducing the requirement for invasive liver biopsy.
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Affiliation(s)
- J K Dowman
- Centre for Liver Research, Institute of Biomedical Research, University of Birmingham, Edgbaston, UK.
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319
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[Fatty liver and its clinical management in obese adolescents]. ACTA ACUST UNITED AC 2011; 58:32-7. [PMID: 21216209 DOI: 10.1016/j.endonu.2010.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 09/13/2010] [Accepted: 10/12/2010] [Indexed: 01/19/2023]
Abstract
Liver steatosis, also called non-alcoholic fatty liver, is characterized by a pathological fat accumulation in the liver, leading to liver damage in the form of inflammation and fibrosis. These histological features are similar to those in alcoholic hepatitis. Obesity is known to be the most common cause of simple steatosis in the preadolescent and adolescent population with a consequent serious health risk. The aim of this study was to provide an update on the concepts, pathophysiology and clinical management of hepatic steatosis secondary to obesity at an early age.
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321
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Williams CD, Stengel J, Asike MI, Torres DM, Shaw J, Contreras M, Landt CL, Harrison SA. Prevalence of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis among a largely middle-aged population utilizing ultrasound and liver biopsy: a prospective study. Gastroenterology 2011; 140:124-31. [PMID: 20858492 DOI: 10.1053/j.gastro.2010.09.038] [Citation(s) in RCA: 1551] [Impact Index Per Article: 119.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 08/03/2010] [Accepted: 09/09/2010] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Prevalence of nonalcoholic fatty liver disease (NAFLD) has not been well established. The purpose of this study was to prospectively define the prevalence of both NAFLD and nonalcoholic steatohepatitis (NASH). METHODS Outpatients 18 to 70 years old were recruited from Brooke Army Medical Center. All patients completed a baseline questionnaire and ultrasound. If fatty liver was identified, then laboratory data and a liver biopsy were obtained. RESULTS Four hundred patients were enrolled. Three hundred and twenty-eight patients completed the questionnaire and ultrasound. Mean age (range, 28-70 years) was 54.6 years (7.35); 62.5% Caucasian, 22% Hispanic, and 11.3% African American; 50.9% female; mean body mass index (BMI) (calculated as kg/m(2)) was 29.8 (5.64); and diabetes and hypertension prevalence 16.5% and 49.7%, respectively. Prevalence of NAFLD was 46%. NASH was confirmed in 40 patients (12.2% of total cohort, 29.9% of ultrasound positive patients). Hispanics had the highest prevalence of NAFLD (58.3%), then Caucasians (44.4%) and African Americans (35.1%). NAFLD patients were more likely to be male (58.9%), older (P = .004), hypertensive (P < .00005), and diabetic (P < .00005). They had a higher BMI (P < .0005), ate fast food more often (P = .049), and exercised less (P = 0.02) than their non-NAFLD counterparts. Hispanics had a higher prevalence of NASH compared with Caucasians (19.4% vs 9.8%; P = .03). Alanine aminotransferase, aspartate aminotransferase, BMI, insulin, Quantitative Insulin-Sensitivity Check Index, and cytokeratin-18 correlated with NASH. Among the 54 diabetic patients, NAFLD was found in 74% and NASH in 22.2%. CONCLUSION Prevalence of NAFLD and NASH is higher than estimated previously. Hispanics and patients with diabetes are at greatest risk for both NAFLD and NASH.
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Affiliation(s)
- Christopher D Williams
- Gastroenterology and Hepatology Service, Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas 78234, USA
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322
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Anty R, Iannelli A, Patouraux S, Bonnafous S, Lavallard VJ, Senni-Buratti M, Amor IB, Staccini-Myx A, Saint-Paul MC, Berthier F, Huet PM, Le Marchand-Brustel Y, Gugenheim J, Gual P, Tran A. A new composite model including metabolic syndrome, alanine aminotransferase and cytokeratin-18 for the diagnosis of non-alcoholic steatohepatitis in morbidly obese patients. Aliment Pharmacol Ther 2010; 32:1315-22. [PMID: 21050233 DOI: 10.1111/j.1365-2036.2010.04480.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Non-invasive approaches are useful to differentiate simple steatosis from non-alcoholic steatohepatitis (NASH) in obese and morbidly obese patients. AIM To develop a new scoring system to diagnose definitive NASH. METHODS Preoperative clinical and biological data including serum caspase 3-generated cytokeratin-18 fragments (CK18) and surgical liver biopsies were obtained from 464 morbidly obese patients who had undergone bariatric surgery. The cohort was divided into two groups: training group (n = 310) and validation group (n = 154). Definitive NASH was defined according to Kleiner's classification with a Non-alcoholic fatty liver disease Activity Score (NAS) ≥5. RESULTS Alanine aminotransferase (ALT), CK18 fragments and the presence of metabolic syndrome were independent predictors for discriminating patients with NAS ≥5 in the training group. These three parameters were used to carry out a scoring system for the prediction of NAS ≥5. Whereas serum CK18 fragment alone had an area under the receiver operating characteristic (AUROC) curve = 0.74, AUROC curves of the scoring system were 0.88 and 0.83 in the training group and the validation group, respectively. CONCLUSION A simple and non-invasive composite model (the Nice Model) including metabolic syndrome, ALT and CK18 fragments is able to predict accurately a non-alcoholic fatty liver disease activity score ≥5 in morbidly obese subjects.
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Affiliation(s)
- R Anty
- Institut National de la Santé et de la Recherche Médicale, Nice, France.
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323
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Marques-Vidal P, Pécoud A, Hayoz D, Paccaud F, Mooser V, Waeber G, Vollenweider P. Normal weight obesity: relationship with lipids, glycaemic status, liver enzymes and inflammation. Nutr Metab Cardiovasc Dis 2010; 20:669-675. [PMID: 19748248 DOI: 10.1016/j.numecd.2009.06.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 03/24/2009] [Accepted: 06/02/2009] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIMS Normal weight obesity (NWO) is defined as an excessive body fat associated with a normal body mass index (BMI) and has been associated with early inflammation, but its relationship with cardiovascular risk factors await investigation. METHODS AND RESULTS Cross-sectional study including 3213 women and 2912 men aged 35-75 years to assess the clinical characteristics of NWO in Lausanne, Switzerland. Body fat was assessed by bioimpedance. NWO was defined as a BMI<25 kg/m(2) and a % body fat ≥66(th) gender-specific percentiles. The prevalence of NWO was 5.4% in women and less than 3% in men, so the analysis was restricted to women. NWO women had a higher % of body fat than overweight women. After adjusting for age, smoking, educational level, physical activity and alcohol consumption, NWO women had higher blood pressure and lipid levels and a higher prevalence of dyslipidaemia (odds-ratio=1.90 [1.34-2.68]) and fasting hyperglycaemia (odds-ratio=1.63 [1.10-2.42]) than lean women, whereas no differences were found between NWO and overweight women. Conversely, no differences were found between NWO and lean women regarding levels of CRP, adiponectin and liver markers (alanine aminotransferase, aspartate aminotransferase and gamma glutamyl transferase). Using other definitions of NWO led to similar conclusions, albeit some differences were no longer significant. CONCLUSION NWO is almost nonexistent in men. Women with NWO present with higher cardiovascular risk factors than lean women, while no differences were found for liver or inflammatory markers. Specific screening of NWO might be necessary in order to implement cardiovascular prevention.
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324
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Adams LA, Feldstein AE. Nonalcoholic steatohepatitis: risk factors and diagnosis. Expert Rev Gastroenterol Hepatol 2010; 4:623-35. [PMID: 20932147 DOI: 10.1586/egh.10.56] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nonalcoholic steatohepatitis (NASH) represents the progressive form of nonalcoholic fatty liver disease with greater potential to lead to liver-related morbidity and mortality. Diagnosing NASH mandates more intensive clinical management and consideration for clinical trials. Currently, the diagnosis of NASH requires a liver biopsy, which is invasive, with drawbacks in sampling and interpretation error. Clinical risk factors for NASH include diabetes and the metabolic syndrome; however, these are not sufficiently predictive of the condition by themselves. Routine liver aminotransaminase levels are not reliable; however, novel plasma hepatocyte apoptosis markers, either alone or in combination with clinical risk factors, are potential noninvasive diagnostic tools for the future.
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Affiliation(s)
- Leon A Adams
- School of Medicine and Pharmacology, University of Western Australia, Sir Charles Gairdner Hospital Unit, Nedlands, WA 6009, Australia
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325
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Ratziu V, Bellentani S, Cortez-Pinto H, Day C, Marchesini G. A position statement on NAFLD/NASH based on the EASL 2009 special conference. J Hepatol 2010; 53:372-84. [PMID: 20494470 DOI: 10.1016/j.jhep.2010.04.008] [Citation(s) in RCA: 753] [Impact Index Per Article: 53.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Accepted: 04/02/2010] [Indexed: 02/06/2023]
Affiliation(s)
- Vlad Ratziu
- Université Pierre et Marie Curie Paris VI, Assistance Publique Hôpitaux de Paris, INSERM UMRS 893, France
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326
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Aasheim ET, Frigstad SO, Søvik TT, Birkeland KI, Haukeland JW. Hyperinsulinemic hypoglycemia and liver cirrhosis presenting after duodenal switch: a case report. Surg Obes Relat Dis 2010; 6:441-3. [DOI: 10.1016/j.soard.2009.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Revised: 11/12/2009] [Accepted: 11/13/2009] [Indexed: 12/26/2022]
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Marsman H, van Werven J, Nederveen A, ten Kate F, Heger M, Stoker J, van Gulik T. Noninvasive quantification of hepatic steatosis inrats using 3.0 T 1H-magnetic resonance spectroscopy. J Magn Reson Imaging 2010; 32:148-54. [DOI: 10.1002/jmri.22064] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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328
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Transient elastography with a new probe for obese patients for non-invasive staging of non-alcoholic steatohepatitis. Eur Radiol 2010; 20:2390-6. [DOI: 10.1007/s00330-010-1820-9] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Revised: 04/28/2010] [Accepted: 05/04/2010] [Indexed: 12/13/2022]
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329
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Pimentel SK, Strobel R, Gonçalves CG, Sakamoto DG, Ivano FH, Coelho JCU. Evaluation of the nonalcoholic fat liver disease fibrosis score for patients undergoing bariatric surgery. ARQUIVOS DE GASTROENTEROLOGIA 2010; 47:170-3. [DOI: 10.1590/s0004-28032010000200010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Accepted: 12/08/2009] [Indexed: 12/25/2022]
Abstract
CONTEXT: Morbidly obese patients have an increased risk for nonalcoholic fat liver disease. Its severe form, nonalcoholic steatohepatitis may cause liver fibrosis. The diagnosis of advanced fibrosis has great value during the pre operative evaluation for bariatric surgery. Currently, liver biopsy is the gold standard for diagnosis of liver fibrosis. OBJECTIVE: To evaluate the nonalcoholic fat liver disease fibrosis score in morbidly obese patients undergoing Roux-en-Y gastric bypass in our population. METHODS: One hundred fifty-eight morbidly obese patients that had undergone bariatric surgery were included. Age, body mass index, hyperglycemia, platelet count, albumin and AST/ALT ratio were applied to the score formula. Scores above 0.676 were indicative of advanced liver fibrosis and scores under -1,455 absence of advanced liver fibrosis. These scores were compared to liver biopsy findings. RESULTS: The presence of advanced fibrosis could be diagnosed with good accuracy, with a positive predictive value of 83.7%. The score had a higher accuracy to exclude advanced fibrosis with a negative predictive value of 97%. Twenty-five patients (16%) had scores between the cutoffs points and were identified as indeterminate. The score sensibility and specificity was 83% and 97% respectively. CONCLUSIONS: The nonalcoholic fat liver disease fibrosis score has high accuracy to identify and exclude advanced liver fibrosis in morbidly obese patients subjected to bariatric surgery.
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Abstract
Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the Western world, and its prevalence is predicted to rise in the future in parallel with rising levels of obesity and type 2 diabetes mellitus. It is commonly associated with insulin resistance. Many patients have coexisting obesity, hypertension, dyslipidaemia or hyperglycaemia, and are at increased risk of developing cardiovascular disease. Although patients with simple steatosis have a good prognosis, a significant percentage will develop nonalcoholic steatohepatitis which may progress to cirrhosis, end-stage liver failure and hepatocellular carcinoma. Despite promising results from several pilot studies and small to medium randomized controlled trials, there is currently no pharmacological agent that is licensed for the treatment of NAFLD. At present the mainstay of treatment for all patients is lifestyle modification using a combination of diet, exercise and behavioural therapy. With recent advances in the understanding of the pathogenesis of NAFLD, the goal of treatment has shifted from simply trying to clear fat from the liver and prevent progressive liver damage to addressing and treating the metabolic risk factors for the condition. To reduce liver-related and cardiovascular morbidity and mortality, all patients with NAFLD should be invited to enrol in adequately powered, randomized controlled studies testing novel therapies, many of which are targeted at reducing insulin resistance or preventing progressive liver disease. Coexisting obesity, hypertension, dyslipidaemia or hyperglycaemia should be treated aggressively. Orlistat, bariatric surgery, angiotensin receptor blockers, statins, fibrates, metformin and thiazolidinediones should all be considered, but treatments should be carefully tailored to meet the specific requirements of each patient. The efficacy and safety of any new treatment, as well as its cost-effectiveness, will need to be carefully evaluated before it can be advocated for widespread clinical use.
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Affiliation(s)
- Sanjeev R. Mehta
- Correspondence to: Dr Sanjeev R. Mehta, BSc, MRCP Department of Endocrinology and Diabetes, Ealing Hospital NHS Trust, Uxbridge Road, London UB1 3HW, UK
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331
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The Decrease of Serum Levels of Human Neutrophil Alpha-Defensins Parallels with the Surgery-Induced Amelioration of NASH in Obesity. Obes Surg 2010; 20:1682-9. [DOI: 10.1007/s11695-010-0129-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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332
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Miquilena Colina ME, García Monzón C. [Obesity and liver disease]. GASTROENTEROLOGIA Y HEPATOLOGIA 2010; 33:591-604. [PMID: 20206411 DOI: 10.1016/j.gastrohep.2009.12.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Accepted: 12/19/2009] [Indexed: 01/01/2023]
Abstract
Obesity is associated with a higher risk of developing non-alcoholic fatty liver disease (NAFLD) and contributes to the progression of liver diseases of distinct etiologies such as chronic hepatitis C virus (HCV) infection. The discovery that adipose tissue is submitted to a state of chronic inflammation able to secrete adipokines has allowed a connection to be established between the metabolic alterations that lead to triglyceride accumulation and liver inflammation, reinforcing the role of hepatocellular lipotoxicity in the pathogenesis of NAFLD. In addition, although HCV genotype 3 induces steatosis, it is currently believed that obesity and its associated alterations, such as insulin resistance, are involved in progression of HCV-mediated liver disease, as well as that of other chronic liver diseases of diverse etiologies.
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Affiliation(s)
- María Eugenia Miquilena Colina
- Unidad de Investigación, Hospital Universitario Santa Cristina, Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, España
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333
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Suzuki A, Binks M, Sha R, Wachholtz A, Eisenson H, Diehl AM. Serum aminotransferase changes with significant weight loss: sex and age effects. Metabolism 2010; 59:177-85. [PMID: 19765777 DOI: 10.1016/j.metabol.2009.06.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Accepted: 06/24/2009] [Indexed: 12/26/2022]
Abstract
In obese subjects, the liver may be differentially affected by significant weight loss depending on as yet unknown factors. We explored clinical factors associated with serum alanine aminotransferase (ALT) changes during significant weight loss in a residential weight loss program. Clinical data from 362 adults who received a comprehensive weight loss intervention (ie, diets, physical fitness, and behavioral modification) in the program were analyzed. Serum ALT was used as a surrogate marker of liver injury. The ALT changes during the program were calculated to create study outcome categories (improvement, no change, or deterioration of ALT during significant weight loss). Variables of demography, lifestyle, and comorbidities at baseline, and total/rate of weight change during the program were explored for associations with the ALT change categories using multiple logistic regression models. Variation by sex was apparent among predictors of ALT deterioration; men with rapid weight loss and women with higher initial body mass index were more likely to experience ALT deterioration, whereas men with prior alcohol consumption were less likely to experience ALT deterioration even after adjusting for baseline ALT (Ps < .03). Variation by age was apparent among predictors of ALT improvement; younger patients with current smoking and older patients with rapid weight loss, diabetes or impaired fasting glucose, or sleep apnea or who followed a reduced-carbohydrate diet were less likely to experience ALT improvement (Ps < .05). A number of clinical factors influence ALT changes during weight loss in sex- and age-specific manners. The patterns that we detected may have pathophysiologic significance beyond the practical implications of our findings in clinical practice related to underlying changes in fat metabolism.
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Affiliation(s)
- Ayako Suzuki
- Division of Gastroenterology, Department of Medicine, Duke University, Durham, NC 27710, USA.
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334
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Affiliation(s)
- J K Dowman
- Centre for Liver Research, Institute of Biomedical Research, University of Birmingham, B15 2TT, Birmingham, UK.
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335
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Nazal L, Riquelme A, Solís N, Pizarro M, Escalona A, Burotto M, Méndez JI, Saint-Jean C, Concha MJ, Giovanni S, Awruch D, Morales A, Baudrand R, Carrasco G, Domínguez MA, Padilla O, Espinoza M, Miquel JF, Nervi F, Arrese M. Hypoadiponectinemia and its association with liver fibrosis in morbidly obese patients. Obes Surg 2010; 20:1400-7. [PMID: 20066503 DOI: 10.1007/s11695-009-0051-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 12/01/2009] [Indexed: 12/11/2022]
Abstract
BACKGROUND Reduced serum levels of adiponectin have been associated with insulin resistance and non-alcoholic fatty liver disease (NAFLD). However, the relationship between serum adiponectin levels and hepatic histology in NAFLD is controversial. The aim of this study was to explore associations between plasma adiponectin concentrations and liver histology in morbidly obese patients. METHODS We conducted a case-control study including obese patients undergoing bariatric surgery and normal controls. Anthropometric, standard biochemical variables as well as plasma adiponectin and leptin levels were determined. Liver biopsy was performed in all patients at the time of surgery. RESULTS Seventy morbidly obese patients (mean BMI, 40.6 ± 5.6 kg/m(2)) met the inclusion criteria and were compared with 69 controls (mean BMI, 22.8 ± 1.6 kg/m(2), p = 0.0001). Thirty patients (43%) had NAFLD and 20 (28%) of them fulfilled the histological criteria for steatohepatitis. Obesity was associated with increased leptin and decreased adiponectin levels. NAFLD patients exhibited decreased levels of serum adiponectin compared with matched controls [median (Q1-Q3), 3.9 (3.2-4.3) vs. 8.6 (6.5-9.2) μg/mL, p < 0.0001]. In univariate analysis, age, gender, type 2 diabetes mellitus, BMI, HOMA-IR, aspartate aminotransferase (AST), alanine aminotransferase, serum glucose, and adiponectin levels were independently associated with hepatic fibrosis. In multivariate analysis, AST [OR = 1.082 (1.000-1.170)], age [OR = 1.119 (1.023-1.225)], and serum adiponectin levels [OR = 0.529 (0.299-0.936)] were significantly associated with the presence of liver fibrosis. CONCLUSIONS NAFLD patients have lower plasma adiponectin concentrations than control subjects. Low adiponectin levels are associated with more severe liver histology. Serum adiponectin may be useful to estimate the severity of liver damage in obese patients with NAFLD.
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Affiliation(s)
- Leyla Nazal
- Department of Gastroenterology, School of Medicine, Pontificia Universidad Católica de Chile, Marcoleta 367, Santiago, Chile
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Abstract
Contemporary life, with its sedentary lifestyles, fast foods, processed foodstuff, and desk-bound service employment, is beset by an epidemic of overweight and obese individuals. The World Health Organization reported that worldwide a billion adults are overweight and at least 30% of them are obese. Moreover, increasing numbers of children are obese. In the United States, 2 National Health and Nutrition Examination Surveys of adults aged 20 to 74 years showed that the prevalence of obesity increased from 15% in the 1976 to 1980 survey to 34% in the 2003 to 2004 survey. Obesity and the metabolic syndrome are unfortunately becoming increasingly common perioperative issues. The ultimate aim of caring for such patients is to find ways to minimize the untoward effects of surgery in patients who are obese or have metabolic syndrome.
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Affiliation(s)
- Phillip D Levin
- Department of Anesthesiology and Critical Care Medicine, Hebrew University Medical Center, Hebrew University-Hadassah School of Medicine, Kiryat Hadassah, POB 12000, Jerusalem 91120, Israel
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Teixeira ARF, Bellodi-Privato M, Carvalheira JB, Pilla VF, Pareja JC, D'Albuquerque LAC. The incapacity of the surgeon to identify NASH in bariatric surgery makes biopsy mandatory. Obes Surg 2009; 19:1678-84. [PMID: 19789933 DOI: 10.1007/s11695-009-9980-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Accepted: 09/04/2009] [Indexed: 02/07/2023]
Abstract
BACKGROUND Nonalcoholic steatohepatitis (NASH) is a morbid condition highly related to obesity. It is unclear if the macroscopic liver appearance correlates with the histopathologic findings. The goal of this prospective study was to determine the relationship between the intraoperative liver appearance and the histopathologic diagnosis of NASH in morbidly obese subjects undergoing bariatric surgery. We also aimed to determine variables that could predict NASH preoperatively. METHODS Consecutive 51 subjects undergoing bariatric surgery without evidence of other liver disease underwent intraoperative liver biopsy. An intraoperative liver visual (macroscopic and tactile examination) was recorded. The liver aspect was compared with the liver histologic findings. Histological assessment was categorized into two groups: NASH and non-NASH (including normal histology and simple steatosis). Clinical and biochemical parameters were obtained from the patient databases and were compared between groups to identify preoperatively predictive factors of NASH. RESULTS From 51 patients, only one presented totally normal histology. Forty-three (86.2%) presented simple steatosis, and seven (13.7%) were classified as NASH. Clinical parameters were not different between groups. At biochemical analysis, only VLDL cholesterol level was significantly higher in the NASH group (p=0.037) but yet within the normal range. Association between macroscopic liver appearance and the presence of histological NASH is poor (sensitivity of 14%, specificity of 56%, positive predictive value of 5%, and negative predictive value of 80%). CONCLUSIONS No predictor of NASH was found. Surgeons' evaluation could not identify NASH individuals. Routine liver biopsy during bariatric operations is mandatory to differentiate NASH and nonalcoholic fatty liver disease.
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Tan Y, Chen JH, Zhang JN, Wang LJ, Liu HX. Therapeutic effects of diet change on nonalcoholic fatty liver disease. Shijie Huaren Xiaohua Zazhi 2009; 17:3394-3401. [DOI: 10.11569/wcjd.v17.i33.3394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the therapeutic effects of diet change on nonalcoholic fatty liver disease (NAFLD) and explore potential mechanisms involved.
METHODS: Eighty Sprague-Dawley male rats were randomly and equally divided into five groups: two normal control groups (NG8 and NG12 groups; fed a normal diet for 8 and 12 weeks, respectively), two high-fat diet groups (HG8 and HG12 groups; fed a high-fat diet for 8 and 12 weeks, respectively), and one diet change group (DG group; fed a high-fat diet for 8 weeks and a normal diet for another 4 weeks). The glucose infusion rate (GIR) was detected by the euglycemic hyperinsulinemic clamp test. The levels of ALT, AST, TG, TC, FFAs, FBS, FIns, TNF-α, SOD and MDA in the serum or liver were tested using a biochemistry automatic analyzer or by radioimmunoassay (RIA). The expression of c-Jun N-terminal protein kinase 1 (JNK1), insulin receptor substrate-1 (IRS-1) and phospho-IRS-1 Ser307 (p-IRS-1Ser307) was detected by Western blot.
RESULTS: Compared with the two matched NG groups, the body weight, liver index, the levels of ALT, AST, TG, TC, FFAs, FIns and TNF-α in the serum and TG, TC, FFAs and MDA in the liver increased (all P < 0.05 or 0.01), the level of SOD in the liver and GIR decreased (t = 4.88 and 7.92, respectively; both P < 0.05), and the expression of JNK1 protein and p-IRS-1Ser307 in the liver was upregulated in the two HG groups (t = 4.39, 5.81; 4.60, and 6.48, respectively). Significant differences were also noted in the above parameters between the HG8 and HG12 groups (all P < 0.05 or 0.01). A positive correlation was found between the expression intensity of JNK1 and insulin resistance (IR). The fatty degeneration of hepatocytes was aggravated in the HG groups with the prolongation of feeding time. In the DG group, all the above parameters were improved but did not return to normal levels as those in the NG groups (all P < 0.05).
CONCLUSION: A rat model of NAFLD and a rat model of NASH are established by feeding rats a high-fat diet for 8 weeks and 12 weeks, respectively. Diet change can improve NAFLD induced by a high fat diet.
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339
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A pilot study using simvastatin in the treatment of nonalcoholic steatohepatitis: A randomized placebo-controlled trial. J Clin Gastroenterol 2009; 43:990-4. [PMID: 19448566 DOI: 10.1097/mcg.0b013e31819c392e] [Citation(s) in RCA: 200] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
GOALS This study was designed to assess the utility of statin therapy in patients with biopsy proven nonalcoholic steatohepatitis (NASH) and hyperlipidemia. BACKGROUND Nonalcoholic fatty liver disease, as the hepatic manifestation of the metabolic syndrome, has become a growing public health concern. Nonalcoholic steatohepatitis (NASH) represents a subset of nonalcoholic fatty liver disease manifested by hepatic fatty infiltration and inflammation which may progress to cirrhosis and its subsequent complications, to include hepatocellular carcinoma. As the metabolic syndrome is thought to be central in the pathogenesis of NASH, it has been speculated that medications that improve metabolic profiles may be beneficial in treatment. In fact, recent studies have demonstrated potential benefit of 3-hydroxy-3-methyglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins), which are used in clinical practice to improve lipid panels. STUDY This double-blinded randomized placebo-controlled trial compared the HMG-CoA reductase inhibitor, simvastatin, with placebo in the treatment of NASH over a 12-month period using serum aminotransferases and repeat liver biopsy to assess for improvement. RESULTS Sixteen patients with biopsy proven NASH were enrolled: 14 completed the study and 10 underwent 1-year repeat liver biopsy. Mean age: 53 years (+/-10.1), mean body mass index: 32.4 (+/-6.1) with 11 male and 5 female patients. Although a 26% reduction in low-density lipoprotein was seen in the simvastatin group compared with placebo, there was no statistically significant improvement in serum aminotransferases, hepatic steatosis, necroinflammatory activity or stage of fibrosis within or between groups. CONCLUSIONS In this pilot trial, monotherapy with simvastatin does not seem to be an effective treatment for NASH.
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340
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Abstract
Current imaging methodologies can detect steatosis with increasing accuracy but cannot detect inflammation or pre-cirrhotic fibrosis or remodeling of the liver parenchyma. Imaging also cannot assess types or localization of hepatic steatosis. With the increased use of rodents to study NAFLD/NASH, careful analysis or reading highlights the fact that liver tissue evaluations reported in many of the popular animal models of NAFLD/NASH often do not imitate many of the significant aspects of the human disease, despite similar terminology applied by investigators. This review will focus on the findings in human disease.
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Affiliation(s)
- Elizabeth M Brunt
- Department of Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid Ave, Box 8118, St. Louis, MO 63110, USA.
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341
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Soverini V, Moscatiello S, Villanova N, Ragni E, Di Domizio S, Marchesini G. Metabolic syndrome and insulin resistance in subjects with morbid obesity. Obes Surg 2009; 20:295-301. [PMID: 19841991 DOI: 10.1007/s11695-009-9999-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Accepted: 10/06/2009] [Indexed: 12/13/2022]
Abstract
BACKGROUND There is evidence that a group of subjects with obesity fits the characteristics of metabolically healthy but obese population. We aimed to assess the prevalence of the metabolic syndrome (MS) in nondiabetic subjects with morbid obesity (body mass index (BMI) > or = 40 kg/m2) and its correlation with insulin resistance. METHODS We analyzed the data of 211 patients (55 males and 156 females) with morbid obesity and without overt diabetes, consecutive referred for weight loss management. All subjects underwent an oral glucose tolerance test, and insulin resistance was calculated by the homeostasis model assessment (HOMA) at baseline and by the oral glucose insulin sensitivity (OGIS) during the glucose and insulin curve. Clinical and biochemical features of MS were also determined. RESULTS The criteria for MS were fulfilled in 74% of cases, and 10 patients had obesity as the sole feature. HOMA-R was normal in 26% of cases, whereas, OGIS was normal only in three females. HOMA-R and OGIS significantly differed in relation to the presence of MS, and a trend was observed in both tests as function of the number of factors of MS (P < 0.001). At logistic regression analysis, after adjustment for age, sex, BMI at age 20 years, present BMI, and waist circumference, OGIS was the only parameter of insulin resistance significantly associated with MS (odds ratio, 2.42; 95% confidence interval, 1.63-3.60). CONCLUSIONS A small number of metabolically healthy, but obese cases exist also in the subgroup of patients with morbid obesity in which insulin resistance maintains its pivotal role.
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Affiliation(s)
- Valentina Soverini
- Clinical Dietetics, Alma Mater Studiorum University, S. Orsola-Malpighi Hospital, Bologna, Italy
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342
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Abstract
Contemporary life, with its sedentary lifestyles, fast foods, processed foodstuff, and desk-bound service employment, is beset by an epidemic of overweight and obese individuals. The World Health Organization reported that worldwide a billion adults are overweight and at least 30% of them are obese. Moreover, increasing numbers of children are obese. In the United States, 2 National Health and Nutrition Examination Surveys of adults aged 20 to 74 years showed that the prevalence of obesity increased from 15% in the 1976 to 1980 survey to 34% in the 2003 to 2004 survey. Obesity and the metabolic syndrome are unfortunately becoming increasingly common perioperative issues. The ultimate aim of caring for such patients is to find ways to minimize the untoward effects of surgery in patients who are obese or have metabolic syndrome.
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Affiliation(s)
- Phillip D Levin
- Department of Anesthesiology and Critical Care Medicine, Hebrew University Medical Center, Hebrew University-Hadassah School of Medicine, Kiryat Hadassah, Jerusalem 91120, Israel
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343
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Adipokine serum levels are related to liver histology in severely obese patients undergoing bariatric surgery. Obes Surg 2009; 19:1313-23. [PMID: 19693638 DOI: 10.1007/s11695-009-9912-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Accepted: 06/24/2009] [Indexed: 02/07/2023]
Abstract
BACKGROUND Leptin, adiponectin, and resistin are adipokines linked to the development of insulin resistance, which plays a central role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). We aimed to define adipokine serum levels in severely obese patients undergoing bariatric surgery and to correlate these with anthropometric and metabolic variables, liver function tests, and histopathological parameters of NAFLD and nonalcoholic steatohepatitis (NASH). METHODS Surgical liver biopsies were obtained from 50 bariatric patients with no history of liver disease or significant alcohol consumption. Serum leptin, adiponectin, and resistin levels were measured, and histology was assessed using Brunt's and Kleiner's scoring systems. RESULTS Waist/hip ratio was significantly higher in men (p = 0.0001), and leptin (p = 0.036) and adiponectin (p = 0.0001) serum levels were higher in women. Forty-one of 50 patients (82%) had histological NAFLD, including 10 (20%) with NASH. Nine patients (18%) had normal liver histology (obese control subgroup). In NAFLD patients, serum adiponectin was negatively correlated with activity grade and fibrosis stage, resistin was negatively correlated with steatosis grade (p = 0.033), while leptin was not related to histology. Leptin/adiponectin ratio showed positive association with stage (p = 0.044). In the subgroup of NASH patients, adiponectin was negatively correlated only with stage (p = 0.01), while there was no correlation between leptin, resistin, or leptin/adiponectin and histology. CONCLUSIONS Serum adiponectin and resistin levels are related to liver histology in bariatric patients and may be indicative of the histological severity of NAFLD and the extent of hepatic steatosis, respectively. Serum leptin levels are not informative of underlying liver histology in severely obese patients.
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344
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Abstract
The advent of liver transplantation has greatly improved the long-term survival of patients with decompensated cirrhosis, and surgery is now performed more frequently in patients with advanced liver disease. The estimation of perioperative mortality is limited by the retrospective nature of and biased patient selection in the available clinical studies. The overall experience is that, in patients with cirrhosis, use of the Child classification and Model for End-Stage Liver Disease (MELD) score provides a reasonably precise estimation of perioperative mortality. Careful preoperative preparation and monitoring to detect complications early in the postoperative course are essential to improve outcomes.
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Affiliation(s)
- Jacqueline G O'Leary
- Division of Hepatology, Department of Internal Medicine, Baylor University Medical Center, 4th Floor Roberts, 3500 Gaston Avenue, Dallas, TX 75246, USA
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345
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Computer-Assisted Ultrasound Analysis of Liver Echogenicity in Obese and Normal-Weight Children. AJR Am J Roentgenol 2009; 192:W201-5. [DOI: 10.2214/ajr.08.2061] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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346
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Jung TW, Lee YJ, Lee MW, Kim SM, Jung TW. Full-length adiponectin protects hepatocytes from palmitate-induced apoptosis via inhibition of c-Jun NH2terminal kinase. FEBS J 2009; 276:2278-84. [DOI: 10.1111/j.1742-4658.2009.06955.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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347
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Fatty Acid Composition and Development of Hepatic Lipidosis During Food Deprivation—Mustelids as a Potential Animal Model for Liver Steatosis. Exp Biol Med (Maywood) 2009; 234:278-86. [DOI: 10.3181/0806-rm-210] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome characterized by asymptomatic hepatic steatosis. It is present in most cases of human obesity but also caused e.g., by rapid weight loss. The patients have decreased n-3 polyunsaturated fatty acid (PUFA) proportions with decreased percentages of 18:3(n-3), 20:5(n-3) and 22:6(n-3) and an increased n-6/n-3 PUFA ratio in liver and/or white adipose tissue (WAT). The present study examined a new experimental model to study liver steatosis with possible future applications to NAFLD. Ten European polecats ( Mustela putorius), the wild form of the domestic ferret, were food-deprived for 5 days with 10 fed animals as controls. The food-deprived animals showed micro- and macrovesicular hepatic steatosis, decreased proportions of 20:5(n-3), 22:6(n-3) and total n-3 PUFA and increased n-6/n-3 PUFA ratios in liver and WAT. At the same time, the product/precursor ratios decreased in liver. The observed effects can be due to selective fatty acid mobilization preferring n-3 PUFA over n-6 PUFA, decreased Δ5 and Δ6 desaturase activities, oxidative stress, decreased arginine availability and activation of the endocannabinoid system. Hepatic lipidosis induced by food deprivation was manifested in the fatty acid composition of the polecat with similarities to human NAFLD despite the different principal etiologies.
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348
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Abstract
Hepatic steatosis (fatty liver) is increasingly recognized as a major component of the metabolic (insulin resistance) syndrome. It can progress to cirrhosis and hepatocellular carcinoma, leading to liver-related mortality. Increasing evidence shows a significant association between hepatic steatosis and hypertension; both are linked to the metabolic syndrome. This review discusses the evidence to support this association, and reviews the diagnosis and management of hepatic steatosis.
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Affiliation(s)
- Matthew J Brookes
- Gastroenterology Unit, City Hospital, Dudley Road, Birmingham B18 7QH, UK
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349
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Leite NC, Salles GF, Araujo ALE, Villela-Nogueira CA, Cardoso CRL. Prevalence and associated factors of non-alcoholic fatty liver disease in patients with type-2 diabetes mellitus. Liver Int 2009; 29:113-9. [PMID: 18384521 DOI: 10.1111/j.1478-3231.2008.01718.x] [Citation(s) in RCA: 341] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND/AIMS Diabetic patients have an increased prevalence and severity of non-alcoholic fatty liver disease (NAFLD). We aimed to investigate the prevalence and the factors associated with the presence of ultrasonographic NAFLD in type-2 diabetic individuals. METHODS In a cross-sectional design study, 180 type-2 diabetic patients were submitted to a complete clinical and laboratory evaluation and abdominal ultrasonography for NAFLD detection and grading. Statistical analysis included bivariate tests, analysis of variance (anova, for increasing severity of steatosis) and multivariate logistic regression. RESULTS The prevalence of ultrasonographic NAFLD was 69.4% [95% confidence interval (CI): 58.3-82.7%]. Patients with NAFLD were more obese, had a higher waist circumference and serum triglyceride and alanine aminotransferase (ALT) levels than those without steatosis. Neither diabetic degenerative complication, nor glycaemic control was associated with liver steatosis. On multivariate analysis, a high serum triglycerides level [>2.82 mmol/L, odds ratio (OR): 3.7-4.1, 95% CI: 1.2-13.3] and a high-normal ALT level (> or =40 U/L, OR: 2.5-2.7, 95% CI: 1.2-5.9) were independently associated with hepatic steatosis, together with either the presence of obesity (OR: 7.1, 95% CI: 3.0-17.0) or of increased waist circumference (OR: 4.8, 95% CI: 1.9-12.2). CONCLUSIONS Type-2 diabetic patients have a high prevalence of ultrasonographic NAFLD and its presence is associated with obesity, mainly abdominal, hypertriglyceridaemia and high-normal ALT levels. Non-alcoholic fatty liver disease in diabetic patients may develop and progress independent of the diabetes progression itself.
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Affiliation(s)
- Nathalie C Leite
- Department of Internal Medicine, University Hospital Clementino Fraga Filho, Medical School, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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350
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Abstract
The obesity epidemic has now spread worldwide. With increase in weight, there is an increase in dysregulated energy metabolism ultimately leading to dysfunction of multiple organ systems recognized as the metabolic syndrome. Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease worldwide, and is thought to be the hepatic manifestation of metabolic syndrome. It is a nondiscriminating disease affecting both children and adults and no socioeconomic class is spared. There is a well-defined increase in both liver-related and all-cause mortality. Current projections foresee a continued worsening in prevalence, especially with the increased rate of childhood obesity. Prevention would be the ultimate goal, but with continued trends in obesity, therapeutic options are needed to manage this chronic liver disease and prevent its complications of cirrhosis and even hepatocellular carcinoma. Therapies will need to be affordable, tolerable, and safe to be useful on such a large scale. This article will discuss some of the basic understanding of NAFLD, as well as review the currently tested therapies, some novel therapies, and potential future therapeutic options.
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Affiliation(s)
- Scott McNear
- Department of Medicine, Brooke Army Medical Center, San Antonio, TX,
USA
| | - Stephen A. Harrison
- Chief of Hepatology, Brooke Army Medical Center, 3851 Roger Brooke Drive,
Fort Sam Houston, TX 78234, USA
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