AIM: To review the effectiveness of exercise as a therapy for nonalcoholic fatty liver disease(NAFLD) and potential benefits in treating insulin resistance and atherosclerosis.METHODS: Medline(EBSCOhost) and Pub Med w...AIM: To review the effectiveness of exercise as a therapy for nonalcoholic fatty liver disease(NAFLD) and potential benefits in treating insulin resistance and atherosclerosis.METHODS: Medline(EBSCOhost) and Pub Med were searched for English-language randomized controlled trials and prospective cohort studies in human adults aged ≥ 18 which investigated the various effects of exercise alone, a combination of exercise and diet, or exercise and diet coupled with behavioral modification on NAFLD from 2010 to Feburary 2015.RESULTS: Eighteen of 2298 available studies were chosen for critical review, which included 6925 patients. Nine(50%) studies were randomized controlled trials. Five(27.8%) studies utilized biopsy to examine the effects of physical activity on hepatic histology. The most commonly employed imaging modality to determine change in hepatic steatosis was hydrogen-magnetic resonance spectroscopy. Only two studies examined the effects of low impact physical activity for patients with significant mobility limitations and one compared the efficacy of aerobic and resistance exercise. No studies examined the exact duration of exercise required for hepatic and metabolic improvement in NAFLD.CONCLUSION: While exercise improved hepatic steatosis and underlying metabolic abnormalities in NAFLD, more studies are needed to define the most beneficial form and duration of exercise treatment.展开更多
Non-alcoholic fatty liver disease(NAFLD) represents the most common and emerging chronic liver disease worldwide. It includes a wide spectrum of liver diseasesranging from simple fatty liver to non-alcoholic steatohep...Non-alcoholic fatty liver disease(NAFLD) represents the most common and emerging chronic liver disease worldwide. It includes a wide spectrum of liver diseasesranging from simple fatty liver to non-alcoholic steatohepatitis(NASH),which may progress to fibrosis and more severe liver complications such as cirrhosis,hepatocellular carcinoma and liver mortality. NAFLD is strongly associated with obesity,insulin resistance,hypertension,and dyslipidaemia,and is now regarded as the liver manifestation of the metabolic syndrome. The increased mortality of patients with NAFLD is primarily a result of cardiovascular disease and,to a lesser extent,to liver related diseases. Increased oxidative stress has been reported in both patients with NAFLD and patient with cardiovascular risk factors. Thus,oxidative stress represents a shared pathophysiological disorder between the two conditions. Several therapeutic strategies targeting oxidative stress reduction in patients with NAFLD have been proposed,with conflicting results. In particular,vitamin E supplementation has been suggested for the treatment of non-diabetic,non-cirrhotic adults with active NASH,although this recommendation is based only on the results of a single randomized controlled trial. Other antioxidant treatments suggested are resveratrol,silybin,L-carnitine and pentoxiphylline. No trial so far,has evaluated the cardiovascular effects of antioxidant treatment in patients with NAFLD. New,large-scale studies including as end-point also the assessment of the atherosclerosis markers are needed.展开更多
Nonalcoholic fatty liver disease(NAFLD) is one of themajor causes of chronic liver injury. NAFLD includes a wide range of clinical conditions from simple steatosis to nonalcoholic steatohepatitis(NASH), advanced fibro...Nonalcoholic fatty liver disease(NAFLD) is one of themajor causes of chronic liver injury. NAFLD includes a wide range of clinical conditions from simple steatosis to nonalcoholic steatohepatitis(NASH), advanced fibrosis, and liver cirrhosis. The histological findings of NASH indicate hepatic steatosis and inflammation with characteristic hepatocyte injury(e.g., ballooning degeneration), as is observed in the patients with alcoholic liver disease. NASH is considered to be a potentially health-threatening disease that can progress to cirrhosis. A liver biopsy remains the most reliable diagnostic method to appropriately diagnose NASH, evaluate the severity of liver fibrosis, and determine the prognosis and optimal treatment. However, this invasive technique is associated with several limitations in routine use, and a number of biomarkers have been developed in order to predict the degree of liver fibrosis. In the present article, we review the current status of noninvasive biomarkers available to estimate liver fibrosis in the patients with NASH. We also discuss our recent findings on the use of the glycated albuminto-glycated hemoglobin ratio, which is a new index that correlates to various chronic liver diseases, including NASH.展开更多
With the high prevalence of obesity, diabetes, and otherfeatures of the metabolic syndrome in United States, nonalcoholic fatty liver disease(NAFLD) has inevitably become a very prevalent chronic liver disease and is ...With the high prevalence of obesity, diabetes, and otherfeatures of the metabolic syndrome in United States, nonalcoholic fatty liver disease(NAFLD) has inevitably become a very prevalent chronic liver disease and is now emerging as one of the leading indications for liver transplantation. Insulin resistance and derangement of lipid metabolism, accompanied by activation of the pro-inflammatory response and fibrogenesis, are essential pathways in the development of the more clinically significant form of NAFLD, known as nonalcoholic steatohepatitis(NASH). Recent advances in the functional characterization of bile acid receptors, such as farnesoid X receptor(FXR) and transmembrane G protein-coupled receptor(TGR) 5, have provided further insight in the pathophysiology of NASH and have led to the development of potential therapeutic targets for NAFLD and NASH. Beyond maintaining bile acid metabolism, FXR and TGR5 also regulate lipid metabolism, maintain glucose homeostasis, increase energy expenditure, and ameliorate hepatic inflammation. These intriguing features have been exploited to develop bile acid analogues to target pathways in NAFLD and NASH pathogenesis. This review provides a brief overview of the pathogenesis of NAFLD and NASH, and then delves into the biological functions of bile acid receptors, particularly with respect to NASH pathogenesis, with a description of the associated experimental data, and, finally, we discuss the prospects of bile acid analogues in the treatment of NAFLD and NASH.展开更多
Non-alcoholic fatty liver disease(NAFLD) is now the most frequent chronic liver disease that occurs across all age groups and is recognized to occur in 14%-30% of the general population, representing a serious and gro...Non-alcoholic fatty liver disease(NAFLD) is now the most frequent chronic liver disease that occurs across all age groups and is recognized to occur in 14%-30% of the general population, representing a serious and growing clinical problem due to the growing prevalence of obesity and overweight. Histologically, it resembles alcoholic liver injury but occurs in patients who deny significant alcohol consumption. NAFLD encompasses a spectrum of conditions, ranging from benign hepatocellular steatosisto inflammatory nonalcoholic steatohepatitis, fibrosis, and cirrhosis. The majority of hepatocellular lipids are stored as triglycerides, but other lipid metabolites, such as free fatty acids, cholesterol, and phospholipids, may also be present and play a role in disease progression. NAFLD is associated with obesity and insulin resistance and is considered the hepatic manifestation of the metabolic syndrome, a combination of medical conditions including type 2 diabetes mellitus, hypertension, hyperlipidemia, and visceral adiposity. Confirmation of the diagnosis of NAFLD can usually be achieved by imaging studies; however, staging the disease requires a liver biopsy. Current treatment relies on weight loss and exercise, although various insulin-sensitizing agents, antioxidants and medications appear promising. The aim of this review is to highlight the current information regarding epidemiology, diagnosis, and management of NAFLD as well as new information about pathogenesis, diagnosis and management of this disease.展开更多
Hepatocellular carcinoma(HCC) is the fifth most common cancer, and obesity has been established as a risk factor for HCC development. Nonalcoholic steatohepatitis(NASH) is apparently the key link between obesity and h...Hepatocellular carcinoma(HCC) is the fifth most common cancer, and obesity has been established as a risk factor for HCC development. Nonalcoholic steatohepatitis(NASH) is apparently the key link between obesity and hepatocarcinogenesis, and obesity also accelerates HCC development synergistically with other risk factors, such as hepatitis virus infection and alcohol consumption. As an explanation for the pathogenesis of NASH, the so-called "two-hit" theory has been widely accepted, but recently, a better model, the so-called "multiple-hits hypothesis" was proposed, which states that many disease-promoting factors may occur in parallel, rather than consecutively. However, the overall mechanism remains largely unknown. Various cell-cell and organ-organ interactions are involved in the pathogenesis of NASH, and thus appropriate in vivo disease models are essential for a deeper understanding. However, replicating the full spectrum of human NASH has been difficult, as NASH involves obesity, insulin resistance, steatohepatitis, fibrosis, and ultimately HCC, and the lack of an appropriate mouse model has been a considerable barrier to determining the missing links among obesity, NASH, and HCC. In recent years, several innovative mouse models presenting obesity- and NASHassociated HCC have been established by modified diets, chemotoxic agents, genetic manipulation, or a combination of these factors, shedding some light on this complex network and providing new therapeutic strategies. Thus, in this paper, I review the mouse models of obesity- and NASH-associated HCC, especially focusing on recent advances and their clinical relevance.展开更多
AIM: To examine whether poly-unsaturated fatty acid(PUFA) therapy is beneficial for improving nonalcoholic steatohepatitis(NASH).METHODS: In total, 78 patients pathologically diagnosed with NASH were enrolled and were...AIM: To examine whether poly-unsaturated fatty acid(PUFA) therapy is beneficial for improving nonalcoholic steatohepatitis(NASH).METHODS: In total, 78 patients pathologically diagnosed with NASH were enrolled and were randomly assigned into the control group and the PUFA therapy group(added 50 mL PUFA with 1:1 ratio of EHA and DHA into daily diet). At the initial analysis and after 6mo of PUFA therapy, parameters of interest including liver enzymes, lipid profiles, markers of inflammation and oxidation, and histological changes were evaluated and compared between these two groups.RESULTS: At the initial analysis, in patients with NASH, serum levels of alanine aminotransferase(ALT)and aspartase aminotransferase(AST) were slightly elevated. Triglyceride(TG), total cholesterol(TC) and low-density lipoprotein cholesterol levels, markers of systemic inflammation [C-reactive protein(CRP)] and oxidation [malondialdehyde(MDA)], as well as fibrosis parameters of type Ⅳ collagen and pro-collagen typeⅢ pro-peptide were also increased beyond the normal range. Six months later, ALT and AST levels were significantly reduced in the PUFA group compared with the control group. In addition, serum levels of TG and TC, CRP and MDA, and type Ⅳ collagen and procollagen type Ⅲ pro-peptide were also simultaneously and significantly reduced. Of note, histological evaluation showed that steatosis grade, necroinflammatory grade, fibrosis stage, and ballooning score were all profoundly improved in comparison to the control group, strongly suggesting that increased PUFA consumption was a potential way to offset NASH progression.CONCLUSION: Increased PUFA consumption is a potential promising approach for NASH prevention and reversal.展开更多
The growing diffusion of nonalcoholic fatty liver disease(NAFLD) is a consequence of the worldwide increase in the prevalence of obesity.Oxidative stress is widely recognized to play a pivotal role in NAFLD evolution ...The growing diffusion of nonalcoholic fatty liver disease(NAFLD) is a consequence of the worldwide increase in the prevalence of obesity.Oxidative stress is widely recognized to play a pivotal role in NAFLD evolution to nonalcoholic steatohepatitis(NASH).Here we review recent evidence suggesting that oxidative stress-derived antigens originating within fatty livers stimulate both humoral and cellular adaptive immune responses and the possible mechanisms involved in sustaining hepatic inflammation in NASH.展开更多
Non-alcoholic fatty liver disease （NAFLD） is consideredto be an independent cardiovascular disease （CVD）risk factor. However, simple steatosis has a benignclinical course without excess mortality. In contrast, the...Non-alcoholic fatty liver disease （NAFLD） is consideredto be an independent cardiovascular disease （CVD）risk factor. However, simple steatosis has a benignclinical course without excess mortality. In contrast, theadvanced form of NAFLD, non-alcoholic steatohepatitis（NASH） with liver fibrosis increases mortality byapproximately 70%, due to an increase in CVDmortality by approximately 300%. Chronic kidneydisease （CKD） may be caused by NAFLD/NASH andit substantially increases CVD risk, especially in thepresence of type 2 diabetes mellitus. Moreover, CKDmay trigger NAFLD/NASH deterioration in a viciouscycle. NAFLD/NASH is also related to increased arterialstiffness （AS）, an independent CVD risk factor thatfurther raises CVD risk. Diagnosis of advanced liverfibrosis （mainly by simple non-invasive tests）, CKD,and increased AS should be made early in the courseof NAFLD and treated appropriately. Lifestyle measuresand statin treatment may help resolve NAFLD/NASHand beneficially affect the CVD risk factors mentioned above.展开更多
基金Supported by The American Association for the Study of Liver Disease(AASLD) Foundation to Dr.VanWagner LB
文摘AIM: To review the effectiveness of exercise as a therapy for nonalcoholic fatty liver disease(NAFLD) and potential benefits in treating insulin resistance and atherosclerosis.METHODS: Medline(EBSCOhost) and Pub Med were searched for English-language randomized controlled trials and prospective cohort studies in human adults aged ≥ 18 which investigated the various effects of exercise alone, a combination of exercise and diet, or exercise and diet coupled with behavioral modification on NAFLD from 2010 to Feburary 2015.RESULTS: Eighteen of 2298 available studies were chosen for critical review, which included 6925 patients. Nine(50%) studies were randomized controlled trials. Five(27.8%) studies utilized biopsy to examine the effects of physical activity on hepatic histology. The most commonly employed imaging modality to determine change in hepatic steatosis was hydrogen-magnetic resonance spectroscopy. Only two studies examined the effects of low impact physical activity for patients with significant mobility limitations and one compared the efficacy of aerobic and resistance exercise. No studies examined the exact duration of exercise required for hepatic and metabolic improvement in NAFLD.CONCLUSION: While exercise improved hepatic steatosis and underlying metabolic abnormalities in NAFLD, more studies are needed to define the most beneficial form and duration of exercise treatment.
文摘Non-alcoholic fatty liver disease(NAFLD) represents the most common and emerging chronic liver disease worldwide. It includes a wide spectrum of liver diseasesranging from simple fatty liver to non-alcoholic steatohepatitis(NASH),which may progress to fibrosis and more severe liver complications such as cirrhosis,hepatocellular carcinoma and liver mortality. NAFLD is strongly associated with obesity,insulin resistance,hypertension,and dyslipidaemia,and is now regarded as the liver manifestation of the metabolic syndrome. The increased mortality of patients with NAFLD is primarily a result of cardiovascular disease and,to a lesser extent,to liver related diseases. Increased oxidative stress has been reported in both patients with NAFLD and patient with cardiovascular risk factors. Thus,oxidative stress represents a shared pathophysiological disorder between the two conditions. Several therapeutic strategies targeting oxidative stress reduction in patients with NAFLD have been proposed,with conflicting results. In particular,vitamin E supplementation has been suggested for the treatment of non-diabetic,non-cirrhotic adults with active NASH,although this recommendation is based only on the results of a single randomized controlled trial. Other antioxidant treatments suggested are resveratrol,silybin,L-carnitine and pentoxiphylline. No trial so far,has evaluated the cardiovascular effects of antioxidant treatment in patients with NAFLD. New,large-scale studies including as end-point also the assessment of the atherosclerosis markers are needed.
文摘Nonalcoholic fatty liver disease(NAFLD) is one of themajor causes of chronic liver injury. NAFLD includes a wide range of clinical conditions from simple steatosis to nonalcoholic steatohepatitis(NASH), advanced fibrosis, and liver cirrhosis. The histological findings of NASH indicate hepatic steatosis and inflammation with characteristic hepatocyte injury(e.g., ballooning degeneration), as is observed in the patients with alcoholic liver disease. NASH is considered to be a potentially health-threatening disease that can progress to cirrhosis. A liver biopsy remains the most reliable diagnostic method to appropriately diagnose NASH, evaluate the severity of liver fibrosis, and determine the prognosis and optimal treatment. However, this invasive technique is associated with several limitations in routine use, and a number of biomarkers have been developed in order to predict the degree of liver fibrosis. In the present article, we review the current status of noninvasive biomarkers available to estimate liver fibrosis in the patients with NASH. We also discuss our recent findings on the use of the glycated albuminto-glycated hemoglobin ratio, which is a new index that correlates to various chronic liver diseases, including NASH.
文摘With the high prevalence of obesity, diabetes, and otherfeatures of the metabolic syndrome in United States, nonalcoholic fatty liver disease(NAFLD) has inevitably become a very prevalent chronic liver disease and is now emerging as one of the leading indications for liver transplantation. Insulin resistance and derangement of lipid metabolism, accompanied by activation of the pro-inflammatory response and fibrogenesis, are essential pathways in the development of the more clinically significant form of NAFLD, known as nonalcoholic steatohepatitis(NASH). Recent advances in the functional characterization of bile acid receptors, such as farnesoid X receptor(FXR) and transmembrane G protein-coupled receptor(TGR) 5, have provided further insight in the pathophysiology of NASH and have led to the development of potential therapeutic targets for NAFLD and NASH. Beyond maintaining bile acid metabolism, FXR and TGR5 also regulate lipid metabolism, maintain glucose homeostasis, increase energy expenditure, and ameliorate hepatic inflammation. These intriguing features have been exploited to develop bile acid analogues to target pathways in NAFLD and NASH pathogenesis. This review provides a brief overview of the pathogenesis of NAFLD and NASH, and then delves into the biological functions of bile acid receptors, particularly with respect to NASH pathogenesis, with a description of the associated experimental data, and, finally, we discuss the prospects of bile acid analogues in the treatment of NAFLD and NASH.
文摘Non-alcoholic fatty liver disease(NAFLD) is now the most frequent chronic liver disease that occurs across all age groups and is recognized to occur in 14%-30% of the general population, representing a serious and growing clinical problem due to the growing prevalence of obesity and overweight. Histologically, it resembles alcoholic liver injury but occurs in patients who deny significant alcohol consumption. NAFLD encompasses a spectrum of conditions, ranging from benign hepatocellular steatosisto inflammatory nonalcoholic steatohepatitis, fibrosis, and cirrhosis. The majority of hepatocellular lipids are stored as triglycerides, but other lipid metabolites, such as free fatty acids, cholesterol, and phospholipids, may also be present and play a role in disease progression. NAFLD is associated with obesity and insulin resistance and is considered the hepatic manifestation of the metabolic syndrome, a combination of medical conditions including type 2 diabetes mellitus, hypertension, hyperlipidemia, and visceral adiposity. Confirmation of the diagnosis of NAFLD can usually be achieved by imaging studies; however, staging the disease requires a liver biopsy. Current treatment relies on weight loss and exercise, although various insulin-sensitizing agents, antioxidants and medications appear promising. The aim of this review is to highlight the current information regarding epidemiology, diagnosis, and management of NAFLD as well as new information about pathogenesis, diagnosis and management of this disease.
基金Supported by Grants from the Japanese Society of GastroenterologyThe Tokyo Society of Medical SciencesKanae Foundation for the Promotion of Medical Science
文摘Hepatocellular carcinoma(HCC) is the fifth most common cancer, and obesity has been established as a risk factor for HCC development. Nonalcoholic steatohepatitis(NASH) is apparently the key link between obesity and hepatocarcinogenesis, and obesity also accelerates HCC development synergistically with other risk factors, such as hepatitis virus infection and alcohol consumption. As an explanation for the pathogenesis of NASH, the so-called "two-hit" theory has been widely accepted, but recently, a better model, the so-called "multiple-hits hypothesis" was proposed, which states that many disease-promoting factors may occur in parallel, rather than consecutively. However, the overall mechanism remains largely unknown. Various cell-cell and organ-organ interactions are involved in the pathogenesis of NASH, and thus appropriate in vivo disease models are essential for a deeper understanding. However, replicating the full spectrum of human NASH has been difficult, as NASH involves obesity, insulin resistance, steatohepatitis, fibrosis, and ultimately HCC, and the lack of an appropriate mouse model has been a considerable barrier to determining the missing links among obesity, NASH, and HCC. In recent years, several innovative mouse models presenting obesity- and NASHassociated HCC have been established by modified diets, chemotoxic agents, genetic manipulation, or a combination of these factors, shedding some light on this complex network and providing new therapeutic strategies. Thus, in this paper, I review the mouse models of obesity- and NASH-associated HCC, especially focusing on recent advances and their clinical relevance.
文摘AIM: To examine whether poly-unsaturated fatty acid(PUFA) therapy is beneficial for improving nonalcoholic steatohepatitis(NASH).METHODS: In total, 78 patients pathologically diagnosed with NASH were enrolled and were randomly assigned into the control group and the PUFA therapy group(added 50 mL PUFA with 1:1 ratio of EHA and DHA into daily diet). At the initial analysis and after 6mo of PUFA therapy, parameters of interest including liver enzymes, lipid profiles, markers of inflammation and oxidation, and histological changes were evaluated and compared between these two groups.RESULTS: At the initial analysis, in patients with NASH, serum levels of alanine aminotransferase(ALT)and aspartase aminotransferase(AST) were slightly elevated. Triglyceride(TG), total cholesterol(TC) and low-density lipoprotein cholesterol levels, markers of systemic inflammation [C-reactive protein(CRP)] and oxidation [malondialdehyde(MDA)], as well as fibrosis parameters of type Ⅳ collagen and pro-collagen typeⅢ pro-peptide were also increased beyond the normal range. Six months later, ALT and AST levels were significantly reduced in the PUFA group compared with the control group. In addition, serum levels of TG and TC, CRP and MDA, and type Ⅳ collagen and procollagen type Ⅲ pro-peptide were also simultaneously and significantly reduced. Of note, histological evaluation showed that steatosis grade, necroinflammatory grade, fibrosis stage, and ballooning score were all profoundly improved in comparison to the control group, strongly suggesting that increased PUFA consumption was a potential way to offset NASH progression.CONCLUSION: Increased PUFA consumption is a potential promising approach for NASH prevention and reversal.
文摘The growing diffusion of nonalcoholic fatty liver disease(NAFLD) is a consequence of the worldwide increase in the prevalence of obesity.Oxidative stress is widely recognized to play a pivotal role in NAFLD evolution to nonalcoholic steatohepatitis(NASH).Here we review recent evidence suggesting that oxidative stress-derived antigens originating within fatty livers stimulate both humoral and cellular adaptive immune responses and the possible mechanisms involved in sustaining hepatic inflammation in NASH.
文摘Non-alcoholic fatty liver disease （NAFLD） is consideredto be an independent cardiovascular disease （CVD）risk factor. However, simple steatosis has a benignclinical course without excess mortality. In contrast, theadvanced form of NAFLD, non-alcoholic steatohepatitis（NASH） with liver fibrosis increases mortality byapproximately 70%, due to an increase in CVDmortality by approximately 300%. Chronic kidneydisease （CKD） may be caused by NAFLD/NASH andit substantially increases CVD risk, especially in thepresence of type 2 diabetes mellitus. Moreover, CKDmay trigger NAFLD/NASH deterioration in a viciouscycle. NAFLD/NASH is also related to increased arterialstiffness （AS）, an independent CVD risk factor thatfurther raises CVD risk. Diagnosis of advanced liverfibrosis （mainly by simple non-invasive tests）, CKD,and increased AS should be made early in the courseof NAFLD and treated appropriately. Lifestyle measuresand statin treatment may help resolve NAFLD/NASHand beneficially affect the CVD risk factors mentioned above.
