Ina Bergheim
Research interests
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InterestsNutrition, Diet, Nutritional Education, Nutritional Medicine, Metabolic Syndrome, Insulin Resistance, Metabolism
Publications
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2.87Impact points
A moderate weight reduction through dietary intervention decreases hepatic fat content in patients with non-alcoholic fatty liver disease (NAFLD): a pilot study.
European journal of nutrition. 04/2012;
PURPOSE: As a diet rich in fructose and an impaired intestinal barrier function have been proposed to be risk factors for the development of non-alcoholic fatty liver disease (NAFLD), the aim of the present pilot study was to determine whether a dietary intervention focusing on a reduction of fructo... [more] PURPOSE: As a diet rich in fructose and an impaired intestinal barrier function have been proposed to be risk factors for the development of non-alcoholic fatty liver disease (NAFLD), the aim of the present pilot study was to determine whether a dietary intervention focusing on a reduction of fructose intake (-50 % in comparison with baseline) has a beneficial effect on liver status. METHODS: A total of 15 patients with NAFLD were enrolled in the study of which 10 finished the study. Fructose and total nutrient intake were assessed using a diet history. At baseline and after 6 months liver status and markers of intestinal barrier function as well as plasminogen activator inhibitor (PAI-) 1 concentration were determined in plasma. RESULTS: Hepatic lipid content and transaminases in plasma as well as body mass index and some parameters of glucose metabolism (e.g., fasting plasma insulin) were significantly lower at the end of the intervention when compared to baseline. Whereas the dietary intervention had no effect on the prevalence of bacterial overgrowth, orocecal transit time and the intestinal permeability or blood ethanol levels endotoxin and PAI-1 concentration in plasma were significantly lower at the end of 6 months intervention period than at baseline. CONCLUSIONS: Taken together, our results indicate that a dietary intervention focusing only on one dietary parameter like fructose may help to decrease intrahepatic fat content of NAFLD patients.
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4.60Impact points
Metformin protects against the development of fructose-induced steatosis in mice: role of the intestinal barrier function.
Laboratory investigation; a journal of technical methods and pathology. 04/2012;
To test the hypothesis that metformin protects against fructose-induced steatosis, and if so, to elucidate underlying mechanisms, C57BL/6J mice were either fed 30% fructose solution or plain water for 8 weeks. Some of the animals were concomitantly treated with metformin (300 mg/kg body weight/day) ... [more] To test the hypothesis that metformin protects against fructose-induced steatosis, and if so, to elucidate underlying mechanisms, C57BL/6J mice were either fed 30% fructose solution or plain water for 8 weeks. Some of the animals were concomitantly treated with metformin (300 mg/kg body weight/day) in the drinking solution. While chronic consumption of 30% fructose solution caused a significant increase in hepatic triglyceride accumulation and plasma alanine-aminotransferase levels, this effect of fructose was markedly attenuated in fructose-fed mice concomitantly treatment with metformin. The protective effects of the metformin treatment on the onset of fructose-induced non-alcoholic fatty liver disease (NAFLD) were associated with a protection against the loss of the tight junction proteins occludin and zonula occludens 1 in the duodenum of fructose-fed mice and the increased translocation of bacterial endotoxin found in mice only fed with fructose. In line with these findings, in metformin-treated fructose-fed animals, hepatic expression of genes of the toll-like receptor-4-dependent signalling cascade as well as the plasminogen-activator inhibitor/cMet-regulated lipid export were almost at the level of controls. Taken together, these data suggest that metformin not only protects the liver from the onset of fructose-induced NAFLD through mechanisms involving its direct effects on hepatic insulin signalling but rather through altering intestinal permeability and subsequently the endotoxin-dependent activation of hepatic Kupffer cells.Laboratory Investigation advance online publication, 23 April 2012; doi:10.1038/labinvest.2012.75.
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1.84Impact points
Nutrition, Intestinal Permeability, and Blood Ethanol Levels Are Altered in Patients with Nonalcoholic Fatty Liver Disease (NAFLD).
Digestive diseases and sciences. 03/2012;
BACKGROUND: A role of an altered dietary pattern (e.g., a diet rich in sugar) but also alterations at the level of the intestinal barrier have repeatedly been discussed to be involved in the development and progression of nonalcoholic fatty liver disease (NAFLD). AIMS: To determine if the nutritiona... [more] BACKGROUND: A role of an altered dietary pattern (e.g., a diet rich in sugar) but also alterations at the level of the intestinal barrier have repeatedly been discussed to be involved in the development and progression of nonalcoholic fatty liver disease (NAFLD). AIMS: To determine if the nutritional intake, intestinal flora, and permeability and the development of NAFLD are related in humans. METHODS: Ten controls and 20 patients with NAFLD ranging from simple steatosis to steatohepatitis were included in the study. Bacterial overgrowth, orocecal transit time, and intestinal permeability were assessed. Alcohol, endotoxin, and plasminogen activator inhibitor (PAI-) 1 concentration were determined in plasma. Nutritional intake was assessed using a dietary history. RESULTS: Despite no differences in the prevalence of bacterial overgrowth and in the orocecal transit time, intestinal permeability, alcohol, and endotoxin levels in plasma were significantly higher in patients with NAFLD than in controls. Similar results were also found for PAI-1 plasma concentrations. Patients with NAFLD had a significantly higher intake of protein, total carbohydrates, and mono- as well as disaccharides than controls. PAI-1, endotoxin, and ALT plasma levels were positively related to total protein and carbohydrate intake. CONCLUSIONS: Taken together, our results indicate that intestinal permeability, endogenous alcohol synthesis, and nutritional intake are markedly altered in patients with NAFLD.
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3.45Impact points
Toll-like receptors 1-9 are elevated in livers with fructose-induced hepatic steatosis.
The British journal of nutrition. 10/2011;
Studies in animals and human subjects indicate that gut-derived bacterial endotoxins may play a critical role in the development of non-alcoholic fatty liver disease (NAFLD). In the present study, we investigated if the liver is also sensitised by other microbial components during the onset of fruct... [more] Studies in animals and human subjects indicate that gut-derived bacterial endotoxins may play a critical role in the development of non-alcoholic fatty liver disease (NAFLD). In the present study, we investigated if the liver is also sensitised by other microbial components during the onset of fructose-induced steatosis in a mouse model. C57BL/6 mice were either fed with 30 % fructose solution or tap water (control) with or without antibiotics for 8 weeks. Expression of toll-like receptors (TLR)1-9, TNF-α, inducible NO synthase (iNOS), myeloid differentiation factor 88 (MyD88) and number of F4/80 positive cells in the liver were assessed. Occludin protein, DNA of microbiota in the small and large intestine and retinol binding protein 4 (RBP4) in plasma were analysed using Western blot, DNA fingerprinting and ELISA, respectively. F4/80 positive cells were determined by immunohistochemistry. The accumulation of TAG found in the livers of fructose-fed mice was associated with a significant induction of TLR 1-4 and 6-8. Plasma RBP4 concentration and hepatic mRNA expression levels of TNF-α, iNOS, MyD88 and number of F4/80 positive cells of fructose-fed animals were significantly higher than those of controls; however, these effects of fructose were attenuated in antibiotic-treated mice. Whereas protein concentration of occludin was lower in the duodenum of fructose-treated mice, no systematic alterations of microbiota were found in this part of the intestine. Taken together, these data support the hypothesis that (1) an increased intestinal translocation of microbial components and (2) an increased number of F4/80 positive cells and induction of several TLR and dependent pathways (e.g. MyD88 and iNOS) may be involved in the onset of fructose-induced NAFLD.
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4.29Impact points
Role of tumor necrosis factor α (TNFα) in the onset of fructose-induced nonalcoholic fatty liver disease in mice.
The Journal of nutritional biochemistry. 06/2011; 22(6):527-34.
Tumor necrosis factor α (TNFα) is known to be involved in dysregulation of hepatic lipid metabolism and insulin signaling. However, whether TNFα also plays a casual role in the onset of fructose-induced nonalcoholic fatty liver disease (NAFLD) has not yet been determined. Therefore, wild-type and TN... [more] Tumor necrosis factor α (TNFα) is known to be involved in dysregulation of hepatic lipid metabolism and insulin signaling. However, whether TNFα also plays a casual role in the onset of fructose-induced nonalcoholic fatty liver disease (NAFLD) has not yet been determined. Therefore, wild-type and TNFα receptor 1 (TNFR1)-/- mice were fed with either 30% fructose solution or plain tap water. Hepatic triglycerides, markers of inflammation and ATP concentration as well as plasma ALT levels were determined. Hepatic PAI-1, SREBP-1, FAS mRNA expression was assessed by real-time RT-PCR. Furthermore, lipid peroxidation and indices of insulin resistance were determined in liver tissue and plasma. In comparison to water controls, chronic intake of 30% fructose solution caused a significant ∼5-fold increase in triglyceride accumulation and neutrophil infiltration in livers of wild-type mice and a ∼8-fold increase in plasma ALT levels. In TNFR1-/- mice, hepatic steatosis was attenuated and neutrophil infiltration in the liver as well as plasma ALT levels was similar to water controls. The protective effect of the TNFR1 deletion against the onset of fructose-induced steatosis was associated with increased phospho AMPK and Akt levels, decreased SREBP-1 and FAS expression in the liver and decreased RBP4 plasma levels, whereas hepatic lipid peroxidation, iNOS protein and ATP levels were similar between wild-type and TNFR1-/- mice fed fructose. Taken together, these data suggest that TNFα plays a casual role in the onset of fructose-induced liver damage as well as insulin resistance in mice through signaling cascades downstream of TNFR1.
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0.74Impact points
A low fructose diet in the treatment of pediatric obesity: a pilot study.
Pediatrics international : official journal of the Japan Pediatric Society. 06/2011; 53(3):303-8.
Over the last three decades the prevalence of overweight and obesity has increased dramatically among children and adolescents worldwide. As the results of animal and human studies suggest that a diet rich in fructose may be a risk factor for the development of overweight, the aim of the pilot study... [more] Over the last three decades the prevalence of overweight and obesity has increased dramatically among children and adolescents worldwide. As the results of animal and human studies suggest that a diet rich in fructose may be a risk factor for the development of overweight, the aim of the pilot study was to evaluate if a dietary counseling aimed at a moderate reduction of dietary fructose intake (-50% in comparison to intake at baseline) has a positive effect on the body mass index (BMI) of overweight and obese children. Fifteen overweight or obese children aged 5-8 years were included into the 3 month dietary intervention study. At baseline and after 4 and 8 weeks children and their parents were trained to reduce fructose in the children's diet. Anthropometric parameters for calculating BMI and BMI standard deviation scores (BMI-SDS) as well as nutritional intake were assessed at baseline, after the 12-week intervention and after 12 week of follow up. After the 12-week intervention children had significantly reduced their total energy, fructose, sucrose and glucose intake. BMI and BMI-SDS were significantly reduced by 0.68 kg/m(2) and 0.21, respectively, at the end of the intervention. At follow up, the BMI-SDS was significantly lower in comparison to baseline while the BMI was only decreased by trend (P= 0.08). The results of our pilot study indicate that counseling aimed towards a moderate reduction of dietary fructose and/or general sugar intake may have a positive effect on BMI in overweight and obese children.
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4.60Impact points
Fructose-induced steatosis in mice: role of plasminogen activator inhibitor-1, microsomal triglyceride transfer protein and NKT cells.
Laboratory investigation; a journal of technical methods and pathology. 03/2011; 91(6):885-95.
Plasminogen activator inhibitor-1 (PAI-1) is an acute-phase protein known to be involved in alcoholic liver disease and hepatic fibrosis. In the present study, the hypothesis that PAI-1 is causally involved in the onset of fructose-induced hepatic steatosis was tested in a mouse model. Wild-type C57... [more] Plasminogen activator inhibitor-1 (PAI-1) is an acute-phase protein known to be involved in alcoholic liver disease and hepatic fibrosis. In the present study, the hypothesis that PAI-1 is causally involved in the onset of fructose-induced hepatic steatosis was tested in a mouse model. Wild-type C57BL/6J and PAI-1⁻/⁻ mice were fed with 30% fructose solution or water for 8 weeks. Markers of hepatic steatosis, expression of PAI-1, apolipoprotein B (ApoB), cluster of differentiation 1d (CD1d), markers of natural killer T (NKT) cells, protein levels of phospho-c-Met and tumor necrosis factor-α (TNF-α) were determined. Activity of the microsomal triglyceride transfer protein (MTTP) was measured in liver tissue. In comparison with water controls, chronic intake of 30% fructose solution caused a significant increase in hepatic triglycerides, PAI-1 expression and plasma alanine aminotransferase levels in wild-type mice. This effect of fructose feeding was markedly attenuated in PAI-1⁻/⁻ mice. Despite no differences in portal endotoxin levels and hepatic TNF-α protein levels between fructose-fed groups, the protective effect of the loss of PAI-1 against the onset of fructose-induced steatosis was associated with a significant increase in phospho-c-Met, phospho Akt, expression of ApoB and activity of MTTP in livers of PAI-1⁻/⁻ mice in comparison with fructose-fed wild types. Moreover, in PAI-1⁻/⁻ mice, expressions of CD1d and markers of CD1d-reactive NKT cells were markedly higher than in wild-type mice; however, expression of markers of activation of CD1d-reactive NKT cells (eg, interleukin-15 and interferon-γ) were only found to be increased in livers of fructose-fed PAI-1⁻/⁻ mice. Taken together, these data suggest that PAI-1 has a causal role in mediating the early phase of fructose-induced liver damage in mice through signaling cascades downstream of Kupffer cells and TNF-α.
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2.67Impact points
Alcoholic liver disease and exacerbation by malnutrition and infections: what animal models are currently available?
Annals of the New York Academy of Sciences. 01/2011; 1216:41-9.
Alcoholic liver disease remains a frequent and serious problem for increasing numbers of patients. Research has expanded our molecular understanding of the cellular basis of disease progression; however, translation into therapy is still hampered by a lack of suitable animal models for alcoholic liv... [more] Alcoholic liver disease remains a frequent and serious problem for increasing numbers of patients. Research has expanded our molecular understanding of the cellular basis of disease progression; however, translation into therapy is still hampered by a lack of suitable animal models for alcoholic liver disease, as well as from consequences of related liver damage due to malnutrition, hepatitis C virus infection, or abuse of other substances. Many patients with liver disease do not simply consume too much alcohol; they also suffer from comorbidities such as obesity or viral hepatitis, and/or may be addicted to other drugs besides alcohol. This review will summarize the currently available animal models to study liver disease due to either single causes or combinations of liver toxic substances/infections and alcohol.
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4.92Impact points
Protective effect of bile acids on the onset of fructose-induced hepatic steatosis in mice.
Journal of lipid research. 12/2010; 51(12):3414-24.
Fructose intake is being discussed as a key dietary factor in the development of nonalcoholic fatty liver disease (NAFLD). Bile acids have been shown to modulate energy metabolism. We tested the effects of bile acids on fructose-induced hepatic steatosis. In C57BL/6J mice treated with a combination ... [more] Fructose intake is being discussed as a key dietary factor in the development of nonalcoholic fatty liver disease (NAFLD). Bile acids have been shown to modulate energy metabolism. We tested the effects of bile acids on fructose-induced hepatic steatosis. In C57BL/6J mice treated with a combination of chenodeoxycholic acid and cholic acid (100 mg/kg body weight each) while drinking water or a 30% fructose solution for eight weeks and appropriate controls, markers of hepatic steatosis, portal endotoxin levels, and markers of hepatic lipogenesis were determined. In mice concomitantly treated with bile acids, the onset of fructose-induced hepatic steatosis was markedly attenuated compared to mice only fed fructose. The protective effects of the bile acid treatment were associated with a downregulation of tumor necrosis factor (TNF)α, sterol regulatory element-binding protein (SREBP)1, FAS mRNA expression, and lipid peroxidation in the liver, whereas hepatic farnesoid X receptor (FXR) or short heterodimer partner (SHP) protein concentration did not differ between groups fed fructose. Rather, bile acid treatment normalized occludin protein concentration in the duodenum, portal endotoxin levels, and markers of Kupffer cell activation to the level of water controls. Taken together, these data suggest that bile acids prevent fructose-induced hepatic steatosis in mice through mechanisms involving protection against the fructose-induced translocation of intestinal bacterial endotoxin.
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8.20Impact points
Role of the inducible nitric oxide synthase in the onset of fructose-induced steatosis in mice.
Antioxidants & redox signaling. 11/2010; 14(11):2121-35.
To test the hypothesis that the inducible nitric oxide synthase (iNOS) is involved in mediating the toll-like receptor 4-dependent effects on the liver in the onset of fructose-induced steatosis, wild-type and iNOS knockout (iNOS(-/-)) mice were either fed tap water or 30% fructose solution for 8 we... [more] To test the hypothesis that the inducible nitric oxide synthase (iNOS) is involved in mediating the toll-like receptor 4-dependent effects on the liver in the onset of fructose-induced steatosis, wild-type and iNOS knockout (iNOS(-/-)) mice were either fed tap water or 30% fructose solution for 8 weeks. Chronic consumption of 30% fructose solution led to a significant increase in hepatic steatosis and inflammation as well as plasma alanine-aminotransferase levels in wild-type mice. This effect of fructose feeding was markedly attenuated in iNOS(-/-) mice. Hepatic lipidperoxidation, concentration of phospho-IκB, nuclear factor κB activity, and tumor necrosis factor-α mRNA level were significantly increased in fructose-fed wild-type mice, whereas in livers of fructose-fed iNOS(-/-) mice, lipidperoxidation, phospho-IκB, nuclear factor κB activity, and tumor necrosis factor-α expression were almost at the level of controls. However, portal endotoxin levels and hepatic myeloid differentiation factor 88 expression were significantly higher in both fructose-fed groups compared to controls. Taken together, these data suggest that (i) the formation of reactive oxygen species in liver is a key factor in the onset of fatty liver and (ii) iNOS is involved in mediating the endotoxin/toll-like receptor 4-dependent effects in the development of fructose-induced fatty liver.
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4.29Impact points
Dietary fructose and intestinal barrier: potential risk factor in the pathogenesis of nonalcoholic fatty liver disease.
The Journal of nutritional biochemistry. 10/2009; 20(9):657-62.
Worldwide, not only the prevalence of obesity has increased dramatically throughout the last three decades but also the incidences of co-morbid conditions such as diabetes type 2 and liver disease have increased. The 'hepatic manifestation of the metabolic syndrome' is called nonalcoholic fa... [more] Worldwide, not only the prevalence of obesity has increased dramatically throughout the last three decades but also the incidences of co-morbid conditions such as diabetes type 2 and liver disease have increased. The 'hepatic manifestation of the metabolic syndrome' is called nonalcoholic fatty liver disease (NAFLD) and comprises a wide spectrum of stages of liver disease ranging from simple steatosis to liver cirrhosis. NAFLD of different stages is found in approximately 30% of adults and approximately 20% in the US population. Not just a general overnutrition but also an elevated intake of certain macronutrients such as fat and carbohydrates and herein particularly fructose has been claimed to be risk factors for the development for NAFLD; however, the etiology of this disease is still unknown. The present review outlines some of the potential mechanisms associated with the development of NAFLD and fructose intake with a particular focus on the role of the intestinal barrier functions.
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3.26Impact points
Serotonin reuptake transporter (SERT) plays a critical role in the onset of fructose-induced hepatic steatosis in mice.
American journal of physiology. Gastrointestinal and liver physiology. 09/2009;
Elevated dietary fructose intake, altered intestinal motility and barrier function may be involved in the development of non-alcoholic fatty liver disease (NAFLD). As intestinal motility and permeability are also regulated through the bioavailability of serotonin (5-HT) we assessed markers of hepati... [more] Elevated dietary fructose intake, altered intestinal motility and barrier function may be involved in the development of non-alcoholic fatty liver disease (NAFLD). As intestinal motility and permeability are also regulated through the bioavailability of serotonin (5-HT) we assessed markers of hepatic injury in serotonin reuptake transporter knockout [SERT((-/-))] and wild-type mice chronically exposed to different monosaccharide solutions (30% glucose or fructose solution) or water for 8 weeks. The significant increase in hepatic triglyceride, tumor necrosis factor-alpha (TNFalpha) and 4-hydroxynonenal (4-HNE) adduct as well as portal endotoxin levels found in fructose fed mice was associated with a significant decrease of SERT and the tight junction occludin in the duodenum. Similar effects were not found in mice fed glucose. In contrast, in SERT((-/-)) mice fed glucose portal endotoxin levels, concentration of occludin and indices of hepatic damage were similar to those found in wild-type and SERT((-/-)) mice fed fructose. In fructose fed mice treated with a 5-HT3 receptor antagonist hepatic steatosis and the loss of SERT in the duodenum were significantly attenuated. Our data suggest that a loss of intestinal SERT is a critical factor in fructose-induced impairment of intestinal barrier function and subsequently the development of steatosis. Key words: intestinal serotonergic system, NAFLD, endotoxin, sugar.
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10.84Impact points
Toll-like receptor 4 is involved in the development of fructose-induced hepatic steatosis in mice.
Hepatology (Baltimore, Md.). 07/2009;
A link between dietary fructose intake, gut-derived endotoxemia, and nonalcoholic fatty liver disease (NAFLD) has been suggested by the results of human and animal studies. To further investigate the role of gut-derived endotoxin in the onset of fructose-induced NAFLD, Toll-like receptor (TLR-) 4-mu... [more] A link between dietary fructose intake, gut-derived endotoxemia, and nonalcoholic fatty liver disease (NAFLD) has been suggested by the results of human and animal studies. To further investigate the role of gut-derived endotoxin in the onset of fructose-induced NAFLD, Toll-like receptor (TLR-) 4-mutant (C3H/HeJ) mice and wildtype (C3H/HouJ) mice were either fed plain water or water enriched with 30% fructose for 8 weeks. Hepatic steatosis, plasma alanine aminotransferase (ALT), and markers of insulin resistance as well as portal endotoxin levels were determined. Hepatic levels of myeloid differentiation factor 88 (MyD88), interferon regulatory factor (IRF) 3 and 7, and tumor necrosis factor alpha (TNFalpha) as well as markers of lipid peroxidation were assessed. Chronic intake of 30% fructose solution caused a significant increase in hepatic steatosis and plasma ALT levels in wildtype animals in comparison to water controls. In fructose-fed TLR-4 mutant mice, hepatic triglyceride accumulation was significantly reduced by approximately 40% in comparison to fructose-fed wildtype mice and plasma ALT levels were at the level of water-fed controls. No difference in portal endotoxin concentration between fructose-fed wildtype and TLR-4-mutant animals was detected. In contrast, hepatic lipid peroxidation, MyD88, and TNFalpha levels were significantly decreased in fructose-fed TLR-4-mutant mice in comparison to fructose-fed wildtype mice, whereas IRF3 and IRF7 expression remained unchanged. Markers of insulin resistance (e.g., plasma TNFalpha, retinol binding protein 4, and hepatic phospho-AKT) were only altered in fructose-fed wildtype animals. Conclusion: Taken together, these data further support the hypothesis that in mice the onset of fructose-induced NAFLD is associated with intestinal bacterial overgrowth and increased intestinal permeability, subsequently leading to an endotoxin-dependent activation of hepatic Kupffer cells. (HEPATOLOGY 2009.).
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4.09Impact points
Cinnamon Extract Protects against Acute Alcohol-Induced Liver Steatosis in Mice.
The Journal of nutrition. 01/2009;
Acute and chronic consumption of alcohol can cause increased intestinal permeability and bacterial overgrowth, thereby increasing portal endotoxin levels. This barrier impairment subsequently leads to an activation of hepatic Kupffer cells and increased release of reactive oxygen species as well as ... [more] Acute and chronic consumption of alcohol can cause increased intestinal permeability and bacterial overgrowth, thereby increasing portal endotoxin levels. This barrier impairment subsequently leads to an activation of hepatic Kupffer cells and increased release of reactive oxygen species as well as of tumor necrosis factor-alpha (TNFalpha). Recent studies have suggested that cinnamon extract may have antiinflammatory effects. In the present study, the protective effects of an alcoholic extract of cinnamon bark was assessed in a mouse model of acute alcohol-induced steatosis and in RAW 264.7 macrophages, used here as a model of Kupffer cells. Acute alcohol ingestion caused a >20-fold increase in hepatic lipid accumulation. Pretreatment with cinnamon extract significantly reduced the hepatic lipid accumulation. This protective effect of cinnamon extract was associated with an inhibition of the induction of the myeloid differentiation primary response gene (MyD) 88, inducible nitric oxide (NO) synthase (iNOS), and plasminogen activator inhibitor 1 mRNA expression found in livers of alcohol-treated animals. In vitro prechallenge with cinnamon extract suppressed lipopolysaccharide (LPS)-induced MyD88, iNOS, and TNFalpha expression as well as NO formation almost completely. Furthermore, LPS treatment of RAW 264.7 macrophages further resulted in degradation of inhibitor kappaB; this effect was almost completely blocked by cinnamon extract. Taken together, our data show that an alcohol extract of cinnamon bark may protect the liver from acute alcohol-induced steatosis through mechanisms involving the inhibition of MyD88 expression.
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4.09Impact points
Nonalcoholic fatty liver disease in humans is associated with increased plasma endotoxin and plasminogen activator inhibitor 1 concentrations and with fructose intake.
The Journal of nutrition. 08/2008; 138(8):1452-5.
Results of animal experiments suggest that consumption of refined carbohydrates (e.g. fructose) can result in small intestinal bacterial overgrowth and increased intestinal permeability, thereby contributing to the development of nonalcoholic fatty liver disease (NAFLD). Furthermore, increased plasm... [more] Results of animal experiments suggest that consumption of refined carbohydrates (e.g. fructose) can result in small intestinal bacterial overgrowth and increased intestinal permeability, thereby contributing to the development of nonalcoholic fatty liver disease (NAFLD). Furthermore, increased plasminogen activator inhibitor (PAI)-1 has been linked to liver damage of various etiologies (e.g. alcohol, endotoxin, nonalcoholic). The aim of the present pilot study was to compare dietary factors, endotoxin, and PAI-1 concentrations between NAFLD patients and controls. We assessed the dietary intake of 12 patients with NAFLD and 6 control subjects. Plasma endotoxin and PAI-1 concentrations as well as hepatic expression of PAI-1 and toll-like receptor (TLR) 4 mRNA were determined. Despite similar total energy, fat, protein, and carbohydrate intakes, patients with NAFLD consumed significantly more fructose than controls. Endotoxin and PAI-1 plasma concentrations as well as hepatic TLR4 and PAI-1 mRNA expression of NAFLD patients were significantly higher than in controls. The plasma PAI-1 concentration was positively correlated with the plasma endotoxin concentration (Spearman r = 0.83; P < 0.005) and hepatic TLR4 mRNA expression (Spearman r = 0.54; P < 0.05). Hepatic mRNA expression of PAI-1 was positively associated with dietary intakes of carbohydrates (Spearman r = 0.67; P < 0.01), glucose (Spearman r = 0.58; P < 0.01), fructose (Spearman r = 0.58; P < 0.01), and sucrose (Spearman r = 0.70; P < 0.01). In conclusion, our results suggest that dietary fructose intake, increased intestinal translocation of bacterial endotoxin, and PAI-1 may contribute to the development of NAFLD in humans.
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7.82Impact points
Antibiotics protect against fructose-induced hepatic lipid accumulation in mice: role of endotoxin.
Journal of hepatology. 07/2008; 48(6):983-92.
BACKGROUND/AIMS: Consumption of refined carbohydrates in soft drinks has been postulated to be a key factor in the development of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to test the effects of ad libitum access to different sugars consumed in drinking water on hep... [more] BACKGROUND/AIMS: Consumption of refined carbohydrates in soft drinks has been postulated to be a key factor in the development of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to test the effects of ad libitum access to different sugars consumed in drinking water on hepatic fat accumulation. METHODS: For 8 weeks, C57BL/J6 mice had free access to solutions containing 30% glucose, fructose, sucrose, or water sweetened with artificial sweetener (AS) or plain water. Body weight, caloric intake, hepatic steatosis and lipid peroxidation were assessed. RESULTS: Total caloric intake and weight gain were highest in mice exposed to glucose. In contrast, hepatic lipid accumulation was significantly higher in mice consuming fructose compared to all other groups. Moreover, endotoxin levels in portal blood and lipid peroxidation as well as TNFalpha expression were significantly higher in fructose fed mice than in all other groups. Concomitant treatment of fructose fed mice with antibiotics (e.g., polymyxin B and neomycin) markedly reduced hepatic lipid accumulation in fructose fed mice. CONCLUSIONS: These data support the hypothesis that high fructose consumption may not only lead to liver damage through overfeeding but also may be directly pro-inflammatory by increasing intestinal translocation of endotoxin.
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12.90Impact points
Metformin prevents alcohol-induced liver injury in the mouse: Critical role of plasminogen activator inhibitor-1.
Gastroenterology. 07/2006; 130(7):2099-112.
BACKGROUND & AIMS: The biguanide drug metformin has recently been found to improve steatosis and liver damage in animal models and in humans with nonalcoholic steatohepatitis. METHODS: The aim of the present study was to determine whether metformin also prevents steatosis and liver damage in mou... [more] BACKGROUND & AIMS: The biguanide drug metformin has recently been found to improve steatosis and liver damage in animal models and in humans with nonalcoholic steatohepatitis. METHODS: The aim of the present study was to determine whether metformin also prevents steatosis and liver damage in mouse models of acute and chronic alcohol exposure. RESULTS: Acute ethanol exposure caused a >20-fold increase in hepatic lipids, peaking 12 hours after administration. Metformin treatment significantly blunted the ethanol effect by >60%. Although metformin is a known inducer of AMP kinase (AMPK) activity, the hepatoprotective property of metformin did not correlate with activation of AMPK or of AMPK-dependent pathways. Instead, the protective effects of metformin correlated with complete prevention of the upregulation of plasminogen activator inhibitor (PAI)-1 caused by ethanol. Indeed, a similar protective effect against acute alcohol-induced lipid accumulation was observed in PAI-1-/- mice. Hepatic fat accumulation caused by chronic enteral ethanol feeding was also prevented by metformin or by knocking out PAI-1. Under these conditions, necroinflammatory changes caused by ethanol were also significantly attenuated. CONCLUSIONS: Taken together, these findings suggest a novel mechanism of action for metformin and identify a new role of PAI-1 in hepatic injury caused by ethanol.
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4.09Impact points
Metformin prevents endotoxin-induced liver injury after partial hepatectomy.
The Journal of pharmacology and experimental therapeutics. 04/2006; 316(3):1053-61.
Metformin [2-(N,N-dimethylcarbamimidoyl)guanidine] is a drug used in the treatment of type 2 diabetes. Recent studies have suggested that metformin may have effects in addition to lowering serum glucose concentrations (e.g., anti-inflammatory). The aim of the present study was to determine whether m... [more] Metformin [2-(N,N-dimethylcarbamimidoyl)guanidine] is a drug used in the treatment of type 2 diabetes. Recent studies have suggested that metformin may have effects in addition to lowering serum glucose concentrations (e.g., anti-inflammatory). The aim of the present study was to determine whether metformin prevents the inflammatory reaction and liver damage in a model of postsurgical sepsis. Accordingly, rats underwent 2/3 partial hepatectomy (PH; or sham surgery); 48 h after surgery, animals were administered endotoxin (LPS; 1.5 mg/kg i.v.). Both PH and LPS alone caused some minor liver damage. However, their combined effect (PH/LPS) was synergistic, leading to robust hepatic damage, as indicated by plasma enzymes and histological assessment. Although metformin treatment did not alter changes caused by PH alone, it almost completely blunted the effects of LPS in the PH/LPS group. Increases in biomarkers of inflammation (e.g., interleukin 6, interferon gamma, and neutrophil number) were also blunted by metformin treatment. Furthermore, PH/LPS caused a >200x increase in hepatic plasminogen activator inhibitor 1 (PAI-1) mRNA expression and plasma PAI-1 protein. These increases were associated with inhibition of hepatic urokinase plasminogen activator activity and an increase in fibrin deposition, indicative of local thrombosis. These effects were markedly reduced by metformin treatment. In conclusion, these data demonstrate that metformin prevents liver damage in a model of postsurgical sepsis in rats by decreasing proinflammatory and hemostatic responses.
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4.09Impact points
Critical role of plasminogen activator inhibitor-1 in cholestatic liver injury and fibrosis.
The Journal of pharmacology and experimental therapeutics. 03/2006; 316(2):592-600.
Plasminogen activator inhibitor-1 (PAI-1) is an acute phase protein known to correlate with hepatic fibrosis. However, whether or not PAI-1 plays a causal role in this disease process had not been directly tested. Therefore, wild-type or PAI-1 knockout (PAI-1(-/-)) mice underwent bile duct ligation.... [more] Plasminogen activator inhibitor-1 (PAI-1) is an acute phase protein known to correlate with hepatic fibrosis. However, whether or not PAI-1 plays a causal role in this disease process had not been directly tested. Therefore, wild-type or PAI-1 knockout (PAI-1(-/-)) mice underwent bile duct ligation. Mice were sacrificed either 3 or 14 days after surgery for assessment of early (i.e., inflammation) and late (i.e., fibrosis) changes caused by bile duct ligation. Liver injury was determined by histopathology and plasma enzymes. Accumulation of extracellular matrix was evaluated by Sirius red staining and by measuring hydroxyproline content. Hepatic expression of PAI-1 was increased approximately 9-fold by bile duct ligation in wild-type mice. Furthermore, early liver injury and inflammation due to bile duct ligation was significantly blunted in PAI-1(-/-) mice in comparison with wild-type mice. Although PAI-1(-/-) mice were significantly protected against the accumulation of extracellular matrix caused by bile duct ligation, increases in expression of indices of stellate cell activation and collagen synthesis caused by bile duct ligation were not attenuated. Protection did, however, correlate with an elevation in hepatic activities of plasminogen activator and matrix metalloprotease activities. In contrast, the increase in tissue inhibitor of metalloproteases-1 protein, a major inhibitor of matrix metalloproteases, caused by bile duct ligation was not altered in PAI-1(-/-) mice compared with the wild-type strain. The increase in hepatic activity of urokinase-type plasminogen activator was also accompanied by more activation of the hepatocyte growth factor receptor c-Met. Taken together, these data suggest that PAI-1 plays a causal role in mediating fibrosis during cholestasis.
Following (3)
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Alfred Königsrainer
University Hospital Tuebinghen -
Kannappan Sriramajayam
Annamalai University -
Astrid Spruss
Universität Hohenheim
Topics (2)
