Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and...Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and cirrhosis.Although NAFLD is a disease of disordered metabolism,it also involves several immune cell-mediated inflammatory processes,either promoting and/or suppressing hepatocyte inflammation through the secretion of pro-inflammatory and/or anti-inflammatory factors to influence the NAFLD process.However,the underlying disease mechanism and the role of immune cells in NAFLD are still under investigation,leaving many open-ended questions.In this review,we presented the recent concepts about the interplay of immune cells in the onset and pathogenesis of NAFLD.We also highlighted the specific non-immune cells exhibiting immunological properties of therapeutic significance in NAFLD.We hope that this review will help guide the development of future NAFLD therapeutics.展开更多
AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without stea...AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD). RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49, P < 0.01). The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001). CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2.展开更多
The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and cirrhosis.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistan...The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and cirrhosis.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress results in increased free fatty acid delivery to the liver and increased hepatic triglyceride(TG)accumulation.An olive oil-rich diet decreases accumulation of TGs in the liver,improves postprandial TGs,glucose and glucagonlike peptide-1 responses in insulin-resistant subjects, and upregulates glucose transporter-2 expression in the liver.The principal mechanisms include:decreased nuclear factor-kappaB activation,decreased lowdensity lipoprotein oxidation,and improved insulin resistance by reduced production of inflammatory cytokines(tumor necrosis factor,interleukin-6)and improvement of jun N-terminal kinase-mediated phosphorylation of insulin receptor substrate-1.The beneficial effect of the Mediterranean diet is derived from monounsaturated fatty acids,mainly from olive oil.In this review,we describe the dietary sources of the monounsaturated fatty acids,the composition of olive oil,dietary fats and their relationship to insulin resistance and postprandial lipid and glucose responses in non-alcoholic steatohepatitis,clinical and experimental studies that assess the relationship between olive oil and NAFLD,and the mechanism by which olive oil ameliorates fatty liver,and we discuss future perspectives.展开更多
Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the ...Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the early sixties. It was not until 1980, however, that Ludwig et al named this condition nonalcoholic steatohepatitis (NASH). Subsequently, nonalcoholic fatty liver disease (NAFLD) has been used as a general name for conditions ranging from simple steatosis through steatohepatitis to end-stage liver disease (cirrhosis). Many studies have demonstrated the significant correlation with obesity and insulin resistance. Other studies have revealed a signifi- cant correlation between hepatic steatosis, cardiovascu- lar disease and increased intima-media thickness. WHO estimated that at least two million patients will develop cirrhosis due to hepatic steatosis in the years to come. Longitudinal cohort studies have demonstrated that those patients with cirrhosis have a similar risk to devel- op hepatocellular carcinoma as those with other causes of cirrhosis. Taken all together, NAFLD has become the third most important indication for liver transplantation. There- fore, training programmes in internal medicine, gastroen- terology and hepatology should stress the importance of diagnosing this entity and treat properly those at risk for developing complications of portal hypertension and con- comittant cardiovascular disease. This review will focus on the clinical characteristics, pathophysiology, imaging tech- niques and the readily available therapeutic options.展开更多
Sedentary lifestyle and poor dietary choices are leading to a weight gain epidemic in westernized countries, subsequently increasing the risk for developing the metabolic syndrome and nonalcoholic fatty liver disease ...Sedentary lifestyle and poor dietary choices are leading to a weight gain epidemic in westernized countries, subsequently increasing the risk for developing the metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). NAFLD is estimated to affect approximate 30% of the general US population and is considered the hepatic manifestation of the metabolic syndrome. Recent findings linking the components of the metabolic syndrome with NAFLD and the progression to nonalcoholic steatohepatitis (NASH) will be reviewed; in particular, the role of visceral adipose tissue, insulin resistance, and adipocytokines in the exacerbation of these conditions. While no therapy has been proven effective for treating NAFLD/NASH, common recommendations will be discussed.展开更多
AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice we...AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice were divided into three groups, normal control were fed standard chow and model group were fed a high-fat diet (HFD) for 16 wk, the intervention group were fed HFD for 16 wk and treated with NaB for 8 wk. Gut microbiota from each group were detected at baseline and at 16 wk, liver histology were evaluated and gastrointestinal barrier indicator such as zonula occluden-1 (ZO-1) were detected by immunohistochemistry and realtime-PCR, further serum or liver endotoxin were determined by ELISA and inflammation-or metabolism-associated genes were quantified by real-time PCR. RESULTS NaB corrected the HFD-induced gut microbiota imbalance in mice, while it considerably elevated the abundances of the beneficial bacteria Christensenellaceae, Blautia and Lactobacillus. These bacteria can produce butyric acid in what seems like a virtuous circle. And butyrate restored HFD induced intestinal mucosa damage, increased the expression of ZO-1 in small intestine, further decreased the levels of gut endotoxin in serum and liver compared with HF group. Endotoxin-associated genes such as TLR4 and Myd88, pro-inflammation genes such as MCP-1, TNF-alpha, IL-1, IL-2, IL-6 and IFN-gamma in liver or epididymal fat were obviously downregulated after NaB intervention. Liver inflammation and fat accumulation were ameliorated, the levels of TG and cholesterol in liver were decreased after NaB intervention, NAS score was significantly decreased, metabolic indices such as FBG and HOMA-IR and liver function indicators ALT and AST were improved compared with HF group. CONCLUSION NaB may restore the dysbiosis of gut microbiota to attenuate steatohepatitis, which is suggested to be a potential gut microbiota modulator and therapeutic substance for NAFLD.展开更多
AIM:To clarify whether nonalcoholic fatty liver disease(NAFLD)increases the risk of cardiovascular disease.METHODS:We carried out a prospective observational study with a total of 1637 apparently healthy Japanese men ...AIM:To clarify whether nonalcoholic fatty liver disease(NAFLD)increases the risk of cardiovascular disease.METHODS:We carried out a prospective observational study with a total of 1637 apparently healthy Japanese men and women who were recruited from a health check-up program.NAFLD was diagnosed by abdominal ultrasonography.The metabolic syndrome(MS)was defined according to the modified National Cholesterol Education Program(NCEP)ATP Ⅲ criteria.Five years after the baseline evaluations,the incidence of cardiovascular disease was assessed by a self-administered questionnaire.RESULTS:Among 1221 participants available for outcome analyses,the incidence of cardiovascular disease was higher in 231 subjects with NAFLD at baseline(5 coronary heart disease,6 ischemic stroke,and 1 cerebral hemorrhage)than 990 subjects without NAFLD(3 coronary heart disease,6 ischemic stroke,and 1 cerebral hemorrhage).Multivariate analyses indicated that NAFLD was a predictor of cardiovascular disease independent of conventional risk factors(odds ratio 4.12,95% CI,1.58 to 10.75,P = 0.004).MS was alsoindependently associated with cardiovascular events.But simultaneous inclusion of NAFLD and MS in a multivariate model revealed that NAFLD but not MS retained a statistically significant correlation with cardiovascular disease.CONCLUSION:Although both of them were predictors of cardiovascular disease,NAFLD but not MS retained a statistically significant correlation with cardiovascular disease in a multivariate model.NAFLD is a strong predictor of cardiovascular disease and may play a central role in the cardiovascular risk of MS.展开更多
Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of ...Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisome proliferators- activated receptors (PPARs) in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPART to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH.展开更多
Mammalian sirtuins are seven members belonging to the silent information regulator 2 family, a group of Class Ⅲ histone/protein deacetylases. Sirtuins(SIRT 1-7) have different subcellular localization and function an...Mammalian sirtuins are seven members belonging to the silent information regulator 2 family, a group of Class Ⅲ histone/protein deacetylases. Sirtuins(SIRT 1-7) have different subcellular localization and function and they regulate cellular protein function through various posttranslational modifications. SIRT1 and 3, the most studied sirtuins, use the product of cellular metabolism nicotinamide adenine dinucleotide as a cofactor to post-translationally deacetylate cellular proteins and consequently link the metabolic status of the cell to protein function. Sirtuins have been shown to play a key role in the development and rescue of various metabolic diseases including non-alcoholic fatty liver disease(NAFLD). NAFLD is currently the most chronic liver disease due mainly to high-calorie consumption and lower physical activity. No pharmacological approach is available to treat NAFLD, the current recommended treatment are lifestyle modification such as weight loss through calorie restriction and exercise. Recent studies have shown downregulation of sirtuins in human as well as animal models of NAFLD indicating an important role of sirtuins in the dynamic pathophysiology of NAFLD. In this review, we highlight the recent knowledge on sirtuins, their role in NAFLD and their unique potential role as novel therapeutic target for NAFLD treatment.展开更多
Nonalcoholic fatty liver disease (NAFLD) includes hepatic steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. NAFLD is the most common liver disorder in the United States and worldwide. Due to the...Nonalcoholic fatty liver disease (NAFLD) includes hepatic steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. NAFLD is the most common liver disorder in the United States and worldwide. Due to the rapid rise of the metabolic syndrome, the prevalence of NAFLD has recently dramatically increased and will continue to increase. NAFLD has also the potential to progress to hepatocellular carcinoma (HCC) or liver failure. NAFLD is strongly linked to caloric overconsumption, physical inactivity, insulin resistance and genetic factors. Although significant progress in understanding the pathogenesis of NAFLD has been achieved in years, the primary metabolic abnormalities leading to lipid accumulation within hepatocytes has remained poorly understood. Mitochondria are critical metabolic organelles serving as "cellular power plants". Accumulating evidence indicate that hepatic mitochondrial dysfunction is crucial to the pathogenesis of NAFLD. This review is focused on the significant role of mitochondria in the development of NAFLD.展开更多
AIM: To investigate the effect of lifestyle intervention on non-alcoholic fatty liver disease (NAFLD) in Chinese obese children. METHODS: Seventy-six obese children aged from 10 to 17 years with NAFLD were enrolled fo...AIM: To investigate the effect of lifestyle intervention on non-alcoholic fatty liver disease (NAFLD) in Chinese obese children. METHODS: Seventy-six obese children aged from 10 to 17 years with NAFLD were enrolled for a one-month intervention and divided randomly into three groups. Group1, consisting of 38 obese children, was an untreated control group without any intervention. Group 2, consisting of 19 obese children in summer camp, was strictly controlled only by life style intervention. Group 3, consisting of 19 obese children, received oral vitamin E therapy at a dose of 100 mg/d. The height, weight, fasting blood glucose (FBG), fasting serum insulin (FINS), plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TCHO) and homeostasis model assent- insulin resistance (HOMA-IR) were measured at baseline and after one month. All patients were underwent to an ultrasonographic study of the liver performed by one operator who was blinded to the groups. RESULTS: The monitor indices of BMI, ALT, AST, TG, TCHO and HOMA-IR were successfully improved except in group 1. BMI and ALT in group 2 were reduced more significantly than in group 3 (2.44 ± 0.82 vs 1.45 ± 0.80, P = 0.001; 88.58 ± 39.99 vs 63.69 ± 27.05, P = 0.040, respectively).CONCLUSION: Both a short-term lifestyle intervention and vitamin E therapy have an effect on NAFLD in obese children. Compared with vitamin E, lifestyle intervention is more effective. Therefore, lifestyle intervention should represent the first step in the management of children with NAFLD.展开更多
AIM: To assess whether treatment with insulinsensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the me...AIM: To assess whether treatment with insulinsensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the methionine choline-deficient diet (MCDD) rat model of non-alcoholic fatty liver disease (NAFLD). METHODS: Rats (n = 6 per group) were treated with different drugs, including MCDD only, MCDD diet with either metformin (200 mg/kg), rosiglitazone (3 mg/kg), metformin plus rosiglitazone (M+R), ezetimibe (2 mg/ kg), valsartan (2 mg/kg), or combination of all drugs for a total of 15 wk. Liver histology, lipids, parameters of oxidative stress and TNF-alpha were measured. RESULTS: Fatty liver (FL) rats demonstrated severe hepatic fatty infiltration (〉 91% fat), with an increase in hepatic TG (+1263%, P 〈 0.001), hepatic cholesterol (+245%, P 〈 0.03), hepatic MDA levels (+225%, P 〈 0.001), serum TNF-alpha (17.8 + 10 vs 7.8 + 0.0, P 〈 0.001), but a decrease in hepatic alpha tocopherol (-74%, P 〈 0.001) as compared to the control rats. Combination therapy with all drugs produced a significant decrease in liver steatosis (-54%), hepatic TG (-64%), hepatic cholesterol (-31%) and hepatic MDA (-70%), but increased hepatic alpha tocopherol (+443%) as compared to FL rats. Combination therapy with ISA alone produced a smaller decrease in liver steatosis (-32% vs -54%, P 〈 0.001) and in hepatic MDA levels (-55% vs -70%, P 〈 0.01), but a similar decrease in hepatic lipids when compared with the all drugs combination. TNF-alpha levels decreased significantly in all treatment groups except in ISA group. CONCLUSION: Combination therapies have a greater effect on liver fat content as compared to monotherapy. Rosiglitazone appears to improve hepatic steatosis to a greater extent than metformin.展开更多
AIM:To investigate the histologic features of the liver in nonalcoholic fatty liver disease (NAFLD) cases according to the presence of metabolic syndrome or its individual components. METHODS:We enrolled 81 patients (...AIM:To investigate the histologic features of the liver in nonalcoholic fatty liver disease (NAFLD) cases according to the presence of metabolic syndrome or its individual components. METHODS:We enrolled 81 patients (40 male,41 fe-male) who were diagnosed with fatty liver by ultraso-nographic scan and fulfi lled the inclusion criteria. First anamnesis,anthropometric,clinical,laboratory and imaging features of all participants were recorded and then liver biopsy was performed after gaining consent from patients. Diagnosis of metabolic syndrome was dependent on patients having 3 or more out of 5 risk criteria defined by the WHO. Biopsy specimens were assessed according to Brunt et al's classification. RESULTS:Sixty-nine of the 81 patients had nonalco-holic steatohepatitis (NASH),11 had simple fatty liver and 1 had cirrhosis according to histologic evaluation. Comparisons were made between two groups of NASH patients,those with and without metabolic syndrome. We did not detect statistically significant differences in liver histology between NASH patients with and wit-hout metabolic syndrome. CONCLUSION:NASH can progress without metabolic risk factors or the presence of metabolic syndrome.展开更多
AIM: To determine the role of leptin system in non-al- coholic fatty liver disease (NAFLD) development by deli- neating the changes in serum levels of leptin and soluble leptin receptor (sOB-R). METHODS: Blood samples...AIM: To determine the role of leptin system in non-al- coholic fatty liver disease (NAFLD) development by deli- neating the changes in serum levels of leptin and soluble leptin receptor (sOB-R). METHODS: Blood samples were collected from 30 consecutive patients with liver-biopsy-proven NAFLD and 30 patients with cholecystolithiasis (stationary phase) as controls. Serum leptin levels were determined by radio- immunoassay and concentration of sOB-R was measured by ELISA. Body mass index (BMI) was calculated for all subjects, and serum insulin, C-peptide, and lipoprotein levels were also detected. RESULTS: Mean serum leptin level and BMI in the NAFLD group were significantly higher than in the con- trols (both P < 0.001), but mean sOB-R level was lower in the NAFLD group when compared to the controls. Both men and women in the NAFLD group had higher mean serum leptin levels and lower sOB-R levels than did the men and women in the control group (all P < 0.001). The- re was a significant negative correlation between serum leptin and sOB-R levels (r = -0.725, P < 0.001). Multiva- riate analysis showed that the percentage of hepatocyte steatosis, sex, BMI, and homeostasis model assessment of insulin resistance (HOMA IR) were independently rela- ted to serum leptin levels. CONCLUSION: Elevated serum leptin seems to be afeature of steatosis, and serum leptin seems to increase as hepatocyte steatosis develops. An enhanced release of leptin is accompanied by an decrease in sOB-R con- centration, which suggests higher resistance of periphe- ral tissues towards the action of leptin.展开更多
AIM: To examine whether visceral fat is associated with non-alcoholic steatohepatitis (NASH), to assess for parameters associated with visceral adiposity and to investigate for factors associated with fibrotic seve...AIM: To examine whether visceral fat is associated with non-alcoholic steatohepatitis (NASH), to assess for parameters associated with visceral adiposity and to investigate for factors associated with fibrotic severity in NASH. METHODS: Thirty NASH and 30 control subjects underwent biochemical tests, anthropometric assessment, bioelectrical impedance, dual energy X-ray absorptiometry and abdominal fat study by CT scan. Liver biopsies were graded according to the Brunt criteria. RESULTS: NASH subjects had elevated blood pressure, body mass index, waist circumference and waist-to-hip ratio. A greater number of diabetes rnellitus, impaired glucose tolerance test and HOMA-IR 〉 3.5 were found in NASH patients. HOMA-IR 〉 2.8 (OR 20.98, 95% CI 3.22-136.62; P 〈 0.001) and visceral fat area 〉 158 cm^2 (OR 18.55, 95% CI 1.60-214.67; P = 0.019) were independent predictors for NASH. Advanced stage of NASH was found in 15 (50%) patients. HOMA-IR 〉 3.5 (OR 23.12, 95% CI 2.00-266.23; P = 0.012) and grading of portal inflammation (OR 7.15, 95% CI 1.63-31.20; P = 0.009) were determined as independent risk factors for advanced stage of NASH. CONCLUSION: Obesity (especially central obesity) and metabolic syndrome are common in Thai NASH. Insulin resistance and elevated visceral fat are risk factors for the presence of NASH. The advanced stage of thedisease is related to insulin resistance.展开更多
文摘Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and cirrhosis.Although NAFLD is a disease of disordered metabolism,it also involves several immune cell-mediated inflammatory processes,either promoting and/or suppressing hepatocyte inflammation through the secretion of pro-inflammatory and/or anti-inflammatory factors to influence the NAFLD process.However,the underlying disease mechanism and the role of immune cells in NAFLD are still under investigation,leaving many open-ended questions.In this review,we presented the recent concepts about the interplay of immune cells in the onset and pathogenesis of NAFLD.We also highlighted the specific non-immune cells exhibiting immunological properties of therapeutic significance in NAFLD.We hope that this review will help guide the development of future NAFLD therapeutics.
文摘AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD). RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49, P < 0.01). The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001). CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2.
文摘The clinical implications of non-alcoholic fatty liver diseases(NAFLD)derive from their potential to progress to fibrosis and cirrhosis.Inappropriate dietary fat intake,excessive intake of soft drinks,insulin resistance and increased oxidative stress results in increased free fatty acid delivery to the liver and increased hepatic triglyceride(TG)accumulation.An olive oil-rich diet decreases accumulation of TGs in the liver,improves postprandial TGs,glucose and glucagonlike peptide-1 responses in insulin-resistant subjects, and upregulates glucose transporter-2 expression in the liver.The principal mechanisms include:decreased nuclear factor-kappaB activation,decreased lowdensity lipoprotein oxidation,and improved insulin resistance by reduced production of inflammatory cytokines(tumor necrosis factor,interleukin-6)and improvement of jun N-terminal kinase-mediated phosphorylation of insulin receptor substrate-1.The beneficial effect of the Mediterranean diet is derived from monounsaturated fatty acids,mainly from olive oil.In this review,we describe the dietary sources of the monounsaturated fatty acids,the composition of olive oil,dietary fats and their relationship to insulin resistance and postprandial lipid and glucose responses in non-alcoholic steatohepatitis,clinical and experimental studies that assess the relationship between olive oil and NAFLD,and the mechanism by which olive oil ameliorates fatty liver,and we discuss future perspectives.
文摘Estimates of people suffering from overweight (one billion) and obesity (300 million) are increasing. The accumulation of triglycerides in the liver, in the absence of excess alcohol intake, has been described in the early sixties. It was not until 1980, however, that Ludwig et al named this condition nonalcoholic steatohepatitis (NASH). Subsequently, nonalcoholic fatty liver disease (NAFLD) has been used as a general name for conditions ranging from simple steatosis through steatohepatitis to end-stage liver disease (cirrhosis). Many studies have demonstrated the significant correlation with obesity and insulin resistance. Other studies have revealed a signifi- cant correlation between hepatic steatosis, cardiovascu- lar disease and increased intima-media thickness. WHO estimated that at least two million patients will develop cirrhosis due to hepatic steatosis in the years to come. Longitudinal cohort studies have demonstrated that those patients with cirrhosis have a similar risk to devel- op hepatocellular carcinoma as those with other causes of cirrhosis. Taken all together, NAFLD has become the third most important indication for liver transplantation. There- fore, training programmes in internal medicine, gastroen- terology and hepatology should stress the importance of diagnosing this entity and treat properly those at risk for developing complications of portal hypertension and con- comittant cardiovascular disease. This review will focus on the clinical characteristics, pathophysiology, imaging tech- niques and the readily available therapeutic options.
文摘Sedentary lifestyle and poor dietary choices are leading to a weight gain epidemic in westernized countries, subsequently increasing the risk for developing the metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). NAFLD is estimated to affect approximate 30% of the general US population and is considered the hepatic manifestation of the metabolic syndrome. Recent findings linking the components of the metabolic syndrome with NAFLD and the progression to nonalcoholic steatohepatitis (NASH) will be reviewed; in particular, the role of visceral adipose tissue, insulin resistance, and adipocytokines in the exacerbation of these conditions. While no therapy has been proven effective for treating NAFLD/NASH, common recommendations will be discussed.
基金the State Key Development Program for Basic Research of China,No.2012CB517501National Natural Science Foundation of China,No.81070322,No.81270491,No.81470840 and No.31400001100 Talents Program,No.XBR2011007h
文摘AIM To investigate whether gut microbiota metabolite sodium butyrate (NaB) is an effective substance for attenuating non-alcoholic fatty liver disease (NAFLD) and the internal mechanisms. METHODS Male C57BL/6J mice were divided into three groups, normal control were fed standard chow and model group were fed a high-fat diet (HFD) for 16 wk, the intervention group were fed HFD for 16 wk and treated with NaB for 8 wk. Gut microbiota from each group were detected at baseline and at 16 wk, liver histology were evaluated and gastrointestinal barrier indicator such as zonula occluden-1 (ZO-1) were detected by immunohistochemistry and realtime-PCR, further serum or liver endotoxin were determined by ELISA and inflammation-or metabolism-associated genes were quantified by real-time PCR. RESULTS NaB corrected the HFD-induced gut microbiota imbalance in mice, while it considerably elevated the abundances of the beneficial bacteria Christensenellaceae, Blautia and Lactobacillus. These bacteria can produce butyric acid in what seems like a virtuous circle. And butyrate restored HFD induced intestinal mucosa damage, increased the expression of ZO-1 in small intestine, further decreased the levels of gut endotoxin in serum and liver compared with HF group. Endotoxin-associated genes such as TLR4 and Myd88, pro-inflammation genes such as MCP-1, TNF-alpha, IL-1, IL-2, IL-6 and IFN-gamma in liver or epididymal fat were obviously downregulated after NaB intervention. Liver inflammation and fat accumulation were ameliorated, the levels of TG and cholesterol in liver were decreased after NaB intervention, NAS score was significantly decreased, metabolic indices such as FBG and HOMA-IR and liver function indicators ALT and AST were improved compared with HF group. CONCLUSION NaB may restore the dysbiosis of gut microbiota to attenuate steatohepatitis, which is suggested to be a potential gut microbiota modulator and therapeutic substance for NAFLD.
基金Supported by a grant from the Gifu Medical Association
文摘AIM:To clarify whether nonalcoholic fatty liver disease(NAFLD)increases the risk of cardiovascular disease.METHODS:We carried out a prospective observational study with a total of 1637 apparently healthy Japanese men and women who were recruited from a health check-up program.NAFLD was diagnosed by abdominal ultrasonography.The metabolic syndrome(MS)was defined according to the modified National Cholesterol Education Program(NCEP)ATP Ⅲ criteria.Five years after the baseline evaluations,the incidence of cardiovascular disease was assessed by a self-administered questionnaire.RESULTS:Among 1221 participants available for outcome analyses,the incidence of cardiovascular disease was higher in 231 subjects with NAFLD at baseline(5 coronary heart disease,6 ischemic stroke,and 1 cerebral hemorrhage)than 990 subjects without NAFLD(3 coronary heart disease,6 ischemic stroke,and 1 cerebral hemorrhage).Multivariate analyses indicated that NAFLD was a predictor of cardiovascular disease independent of conventional risk factors(odds ratio 4.12,95% CI,1.58 to 10.75,P = 0.004).MS was alsoindependently associated with cardiovascular events.But simultaneous inclusion of NAFLD and MS in a multivariate model revealed that NAFLD but not MS retained a statistically significant correlation with cardiovascular disease.CONCLUSION:Although both of them were predictors of cardiovascular disease,NAFLD but not MS retained a statistically significant correlation with cardiovascular disease in a multivariate model.NAFLD is a strong predictor of cardiovascular disease and may play a central role in the cardiovascular risk of MS.
文摘Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and can result in nonalcoholic steatohepatitis (NASH) and progressive liver disease including cirrhosis and hepatocellular carcinoma. A growing body of literature implicates the peroxisome proliferators- activated receptors (PPARs) in the pathogenesis and treatment of NAFLD. These nuclear hormone receptors impact on hepatic triglyceride accumulation and insulin resistance. The aim of this review is to describe the data linking PPARα and PPART to NAFLD/NASH and to discuss the use of PPAR ligands for the treatment of NASH.
文摘Mammalian sirtuins are seven members belonging to the silent information regulator 2 family, a group of Class Ⅲ histone/protein deacetylases. Sirtuins(SIRT 1-7) have different subcellular localization and function and they regulate cellular protein function through various posttranslational modifications. SIRT1 and 3, the most studied sirtuins, use the product of cellular metabolism nicotinamide adenine dinucleotide as a cofactor to post-translationally deacetylate cellular proteins and consequently link the metabolic status of the cell to protein function. Sirtuins have been shown to play a key role in the development and rescue of various metabolic diseases including non-alcoholic fatty liver disease(NAFLD). NAFLD is currently the most chronic liver disease due mainly to high-calorie consumption and lower physical activity. No pharmacological approach is available to treat NAFLD, the current recommended treatment are lifestyle modification such as weight loss through calorie restriction and exercise. Recent studies have shown downregulation of sirtuins in human as well as animal models of NAFLD indicating an important role of sirtuins in the dynamic pathophysiology of NAFLD. In this review, we highlight the recent knowledge on sirtuins, their role in NAFLD and their unique potential role as novel therapeutic target for NAFLD treatment.
文摘Nonalcoholic fatty liver disease (NAFLD) includes hepatic steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. NAFLD is the most common liver disorder in the United States and worldwide. Due to the rapid rise of the metabolic syndrome, the prevalence of NAFLD has recently dramatically increased and will continue to increase. NAFLD has also the potential to progress to hepatocellular carcinoma (HCC) or liver failure. NAFLD is strongly linked to caloric overconsumption, physical inactivity, insulin resistance and genetic factors. Although significant progress in understanding the pathogenesis of NAFLD has been achieved in years, the primary metabolic abnormalities leading to lipid accumulation within hepatocytes has remained poorly understood. Mitochondria are critical metabolic organelles serving as "cellular power plants". Accumulating evidence indicate that hepatic mitochondrial dysfunction is crucial to the pathogenesis of NAFLD. This review is focused on the significant role of mitochondria in the development of NAFLD.
基金Science and Technology Department of Zhejiang Province of China, No. 2005C24001, No. 2004C30064
文摘AIM: To investigate the effect of lifestyle intervention on non-alcoholic fatty liver disease (NAFLD) in Chinese obese children. METHODS: Seventy-six obese children aged from 10 to 17 years with NAFLD were enrolled for a one-month intervention and divided randomly into three groups. Group1, consisting of 38 obese children, was an untreated control group without any intervention. Group 2, consisting of 19 obese children in summer camp, was strictly controlled only by life style intervention. Group 3, consisting of 19 obese children, received oral vitamin E therapy at a dose of 100 mg/d. The height, weight, fasting blood glucose (FBG), fasting serum insulin (FINS), plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (TCHO) and homeostasis model assent- insulin resistance (HOMA-IR) were measured at baseline and after one month. All patients were underwent to an ultrasonographic study of the liver performed by one operator who was blinded to the groups. RESULTS: The monitor indices of BMI, ALT, AST, TG, TCHO and HOMA-IR were successfully improved except in group 1. BMI and ALT in group 2 were reduced more significantly than in group 3 (2.44 ± 0.82 vs 1.45 ± 0.80, P = 0.001; 88.58 ± 39.99 vs 63.69 ± 27.05, P = 0.040, respectively).CONCLUSION: Both a short-term lifestyle intervention and vitamin E therapy have an effect on NAFLD in obese children. Compared with vitamin E, lifestyle intervention is more effective. Therefore, lifestyle intervention should represent the first step in the management of children with NAFLD.
文摘AIM: To assess whether treatment with insulinsensitizing agents (ISAs) in combination with ezetimibe and valsartan have greater effect on hepatic fat content and lipid peroxidation compared to monotherapy in the methionine choline-deficient diet (MCDD) rat model of non-alcoholic fatty liver disease (NAFLD). METHODS: Rats (n = 6 per group) were treated with different drugs, including MCDD only, MCDD diet with either metformin (200 mg/kg), rosiglitazone (3 mg/kg), metformin plus rosiglitazone (M+R), ezetimibe (2 mg/ kg), valsartan (2 mg/kg), or combination of all drugs for a total of 15 wk. Liver histology, lipids, parameters of oxidative stress and TNF-alpha were measured. RESULTS: Fatty liver (FL) rats demonstrated severe hepatic fatty infiltration (〉 91% fat), with an increase in hepatic TG (+1263%, P 〈 0.001), hepatic cholesterol (+245%, P 〈 0.03), hepatic MDA levels (+225%, P 〈 0.001), serum TNF-alpha (17.8 + 10 vs 7.8 + 0.0, P 〈 0.001), but a decrease in hepatic alpha tocopherol (-74%, P 〈 0.001) as compared to the control rats. Combination therapy with all drugs produced a significant decrease in liver steatosis (-54%), hepatic TG (-64%), hepatic cholesterol (-31%) and hepatic MDA (-70%), but increased hepatic alpha tocopherol (+443%) as compared to FL rats. Combination therapy with ISA alone produced a smaller decrease in liver steatosis (-32% vs -54%, P 〈 0.001) and in hepatic MDA levels (-55% vs -70%, P 〈 0.01), but a similar decrease in hepatic lipids when compared with the all drugs combination. TNF-alpha levels decreased significantly in all treatment groups except in ISA group. CONCLUSION: Combination therapies have a greater effect on liver fat content as compared to monotherapy. Rosiglitazone appears to improve hepatic steatosis to a greater extent than metformin.
基金Supported by Uludag University Scientific Project Grant
文摘AIM:To investigate the histologic features of the liver in nonalcoholic fatty liver disease (NAFLD) cases according to the presence of metabolic syndrome or its individual components. METHODS:We enrolled 81 patients (40 male,41 fe-male) who were diagnosed with fatty liver by ultraso-nographic scan and fulfi lled the inclusion criteria. First anamnesis,anthropometric,clinical,laboratory and imaging features of all participants were recorded and then liver biopsy was performed after gaining consent from patients. Diagnosis of metabolic syndrome was dependent on patients having 3 or more out of 5 risk criteria defined by the WHO. Biopsy specimens were assessed according to Brunt et al's classification. RESULTS:Sixty-nine of the 81 patients had nonalco-holic steatohepatitis (NASH),11 had simple fatty liver and 1 had cirrhosis according to histologic evaluation. Comparisons were made between two groups of NASH patients,those with and without metabolic syndrome. We did not detect statistically significant differences in liver histology between NASH patients with and wit-hout metabolic syndrome. CONCLUSION:NASH can progress without metabolic risk factors or the presence of metabolic syndrome.
文摘AIM: To determine the role of leptin system in non-al- coholic fatty liver disease (NAFLD) development by deli- neating the changes in serum levels of leptin and soluble leptin receptor (sOB-R). METHODS: Blood samples were collected from 30 consecutive patients with liver-biopsy-proven NAFLD and 30 patients with cholecystolithiasis (stationary phase) as controls. Serum leptin levels were determined by radio- immunoassay and concentration of sOB-R was measured by ELISA. Body mass index (BMI) was calculated for all subjects, and serum insulin, C-peptide, and lipoprotein levels were also detected. RESULTS: Mean serum leptin level and BMI in the NAFLD group were significantly higher than in the con- trols (both P < 0.001), but mean sOB-R level was lower in the NAFLD group when compared to the controls. Both men and women in the NAFLD group had higher mean serum leptin levels and lower sOB-R levels than did the men and women in the control group (all P < 0.001). The- re was a significant negative correlation between serum leptin and sOB-R levels (r = -0.725, P < 0.001). Multiva- riate analysis showed that the percentage of hepatocyte steatosis, sex, BMI, and homeostasis model assessment of insulin resistance (HOMA IR) were independently rela- ted to serum leptin levels. CONCLUSION: Elevated serum leptin seems to be afeature of steatosis, and serum leptin seems to increase as hepatocyte steatosis develops. An enhanced release of leptin is accompanied by an decrease in sOB-R con- centration, which suggests higher resistance of periphe- ral tissues towards the action of leptin.
文摘AIM: To examine whether visceral fat is associated with non-alcoholic steatohepatitis (NASH), to assess for parameters associated with visceral adiposity and to investigate for factors associated with fibrotic severity in NASH. METHODS: Thirty NASH and 30 control subjects underwent biochemical tests, anthropometric assessment, bioelectrical impedance, dual energy X-ray absorptiometry and abdominal fat study by CT scan. Liver biopsies were graded according to the Brunt criteria. RESULTS: NASH subjects had elevated blood pressure, body mass index, waist circumference and waist-to-hip ratio. A greater number of diabetes rnellitus, impaired glucose tolerance test and HOMA-IR 〉 3.5 were found in NASH patients. HOMA-IR 〉 2.8 (OR 20.98, 95% CI 3.22-136.62; P 〈 0.001) and visceral fat area 〉 158 cm^2 (OR 18.55, 95% CI 1.60-214.67; P = 0.019) were independent predictors for NASH. Advanced stage of NASH was found in 15 (50%) patients. HOMA-IR 〉 3.5 (OR 23.12, 95% CI 2.00-266.23; P = 0.012) and grading of portal inflammation (OR 7.15, 95% CI 1.63-31.20; P = 0.009) were determined as independent risk factors for advanced stage of NASH. CONCLUSION: Obesity (especially central obesity) and metabolic syndrome are common in Thai NASH. Insulin resistance and elevated visceral fat are risk factors for the presence of NASH. The advanced stage of thedisease is related to insulin resistance.