scholarly journals The Influence of Trehalose on Atherosclerosis and Hepatic Steatosis in Apolipoprotein E Knockout Mice

2019 ◽  
Vol 20 (7) ◽  
pp. 1552 ◽  
Author(s):  
Aneta Stachowicz ◽  
Anna Wiśniewska ◽  
Katarzyna Kuś ◽  
Anna Kiepura ◽  
Anna Gębska ◽  
...  
Keyword(s):  
Apolipoprotein E ◽  
Hepatic Steatosis ◽  
Molecular Mechanisms ◽  
Plasma Cholesterol ◽  
Liver Steatosis ◽  
Therapeutic Interventions ◽  
Prolonged Treatment ◽  
High Density Lipoproteins ◽  
Chow Diet ◽  
Apolipoprotein E Knockout Mice

Atherosclerosis and nonalcoholic fatty liver disease (NAFLD) are frequent causes of death in the Western countries. Recently, it has been shown that autophagy dysfunction plays an important role in the pathogenesis of both atherosclerosis and NAFLD; thus, activators of autophagy might be useful for novel therapeutic interventions. Trehalose—a naturally occuring disaccharide present in plants, bacteria, fungi, insects, and certain types of shrimps—is a known inducer of autophagy. However, according to the literature, its anti-atherosclerotic and anti-steatotic potential seem to depend on the experimental setting. The aim of our study was to comprehensively describe the influence of a prolonged treatment with orally administered trehalose on the development of atherosclerotic lesions and hepatic steatosis in apolipoprotein E knockout (apoE−/−) mice in an experimental set up reflecting both moderate and severe proatherogenic conditions: male apoE−/− mice on a chow diet (CD) and female apoE−/− mice fed with a high-fat diet (HFD). We found that exogenous trehalose inhibited atherosclerosis and attenuated hepatic steatosis in apoE−/− mice. Such effects of trehalose were not associated with changes of plasma cholesterol, low-density lipoproteins (LDL), or high-density lipoproteins (HDL). Moreover, the anti-steatotic action of trehalose in the liver was associated with the induction of autophagy. The exact molecular mechanisms of both the anti-atherosclerotic action of trehalose and its inhibitory effect on liver steatosis require further clarification.

scholarly journals Vitamin A-Deficient Diet Accelerated Atherogenesis in Apolipoprotein E−/−Mice and Dietaryβ-Carotene Prevents This Consequence

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Noa Zolberg Relevy ◽  
Dror Harats ◽  
Ayelet Harari ◽  
Ami Ben-Amotz ◽  
Rafael Bitzur ◽  
...  
Keyword(s):  
Vitamin A ◽  
Apolipoprotein E ◽  
Vitamin A Deficiency ◽  
Plasma Cholesterol ◽  
Atherosclerotic Lesion ◽  
Dietary Vitamin ◽  
Control Group ◽  
Chow Diet ◽  
Deficient Diet ◽  
Aortic Sinus

Vitamin A is involved in regulation of glucose concentrations, lipid metabolism, and inflammation, which are major risk factors for atherogenesis. However, the effect of vitamin A deficiency on atherogenesis has not been investigated. Therefore, the objective of the current study was to examine whether vitamin A deficiency accelerates atherogenesis in apolipoprotein E-deficient mice (apoE−/−). ApoE−/−mice were allocated into the following groups: control, fed vitamin A-containing chow diet; BC, fed chow diet fortified withDunaliellapowder containingβc isomers; VAD, fed vitamin A-deficient diet; and VAD-BC group, fed vitamin A-deficient diet fortified with aDunaliellapowder. Following 15 weeks of treatment, liver retinol concentration had decreased significantly in the VAD group to about 30% that of control group. Vitamin A-deficient diet significantly increased both plasma cholesterol concentrations and the atherosclerotic lesion area at the aortic sinus (+61%) compared to the control group. Dietaryβc fortification inhibited the elevation in plasma cholesterol and retarded atherogenesis in mice fed the vitamin A-deficient diet. The results imply that dietary vitamin A deficiency should be examined as a risk factor for atherosclerosis and that dietaryβc, as a sole source of retinoids, can compensate for vitamin A deficiency.

scholarly journals Disruption of hepatic small heterodimer partner induces dissociation of steatosis and inflammation in experimental nonalcoholic steatohepatitis

2019 ◽  
Vol 295 (4) ◽  
pp. 994-1008 ◽  
Author(s):  
Nancy Magee ◽  
An Zou ◽  
Priyanka Ghosh ◽  
Forkan Ahamed ◽  
Don Delker ◽  
...  
Keyword(s):  
Nonalcoholic Steatohepatitis ◽  
Molecular Mechanisms ◽  
Liver Steatosis ◽  
Chow Diet ◽  
Peroxisome Proliferator ◽  
Rna Seq ◽  
Hepatic Inflammation ◽  
Peroxisome Proliferator Activated Receptor ◽  
Small Heterodimer Partner

Nonalcoholic steatohepatitis (NASH) is a leading cause of chronic liver disease worldwide and is characterized by steatosis, inflammation, and fibrosis. The molecular mechanisms underlying NASH development remain obscure. The nuclear receptor small heterodimer partner (Shp) plays a complex role in lipid metabolism and inflammation. Here, we sought to determine SHP's role in regulating steatosis and inflammation in NASH. Shp deletion in murine hepatocytes (ShpHep−/−) resulted in massive infiltration of macrophages and CD4+ T cells in the liver. ShpHep−/− mice developed reduced steatosis, but surprisingly increased hepatic inflammation and fibrosis after being fed a high-fat, -cholesterol, and -fructose (HFCF) diet. RNA-Seq analysis revealed that pathways involved in inflammation and fibrosis are significantly activated in the liver of ShpHep−/− mice fed a chow diet. After having been fed the HFCF diet, WT mice displayed up-regulated peroxisome proliferator-activated receptor γ (Pparg) signaling in the liver; however, this response was completely abolished in the ShpHep−/− mice. In contrast, livers of ShpHep−/− mice had consistent NF-κB activation. To further characterize the role of Shp specifically in the transition of steatosis to NASH, mice were fed the HFCF diet for 4 weeks, followed by Shp deletion. Surprisingly, Shp deletion after steatosis development exacerbated hepatic inflammation and fibrosis without affecting liver steatosis. Together, our results indicate that, depending on NASH stage, hepatic Shp plays an opposing role in steatosis and inflammation. Mechanistically, Shp deletion in hepatocytes activated NF-κB and impaired Pparg activation, leading to the dissociation of steatosis, inflammation, and fibrosis in NASH development.

scholarly journals The peroxisome-proliferator-activated receptor alpha agonist ciprofibrate severely aggravates hypercholesterolaemia and accelerates the development of atherosclerosis in mice lacking apolipoprotein E

2003 ◽  
Vol 373 (3) ◽  
pp. 941-947 ◽  
Author(s):  
Tao FU ◽  
Papreddy KASHIREDDY ◽  
Jayme BORENSZTAJN
Keyword(s):  
Apolipoprotein E ◽  
Plasma Cholesterol ◽  
Acid Oxidation ◽  
Chow Diet ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
Very Low Density Lipoproteins ◽  
Peroxisome Proliferator Activated Receptor ◽  
Atherosclerotic Lesions ◽  
Deficient Mice

Mice lacking apolipoprotein E (apoE) are characterized by severe hypercholesterolaemia, caused by an abnormal accumulation of apolipoprotein B-48 (apoB-48)-carrying remnants of chylomicrons and very-low-density lipoproteins (VLDL) in the plasma, and by the spontaneous development of atherosclerotic lesions. Ciprofibrate is a hypolipidaemic compound that acts primarily by enhancing the oxidation of fatty acids in the liver and, consequently, decreasing the production of hepatic VLDL. In the present study, homozygous apoE-deficient mice were fed with a normal chow diet, supplemented with ciprofibrate. We report that, as anticipated, ciprofibrate treatment (a) stimulated hepatic fatty acid oxidation, as indicated by an increase in the mRNA levels of peroxisomal fatty acyl-CoA oxidase (AOX) and peroxisomal bifunctional enzyme, and (b) decreased the hepatic secretion of VLDL into the plasma, as determined by treating the animals with Triton WR-1339. Paradoxically, the apoE-deficient mice developed a 3–4-fold increase in their plasma cholesterol levels. A similar effect was observed in apoE-deficient mice treated with other peroxisome-proliferator-activated receptor α agonists (fenofibrate, bezafibrate and WY14,643). By FPLC of the plasma and Western-blot analysis, we determined that the enhanced hypercholesterolaemia was due to an increased accumulation of apoB-48-carrying lipoprotein remnants in the plasma. Consistent with this finding, atherosclerotic lesions in animals treated with ciprofibrate for 90 days were considerably more advanced than in untreated animals. These results indicate that the ciprofibrate-induced accumulation of apoB-48-carrying remnants in apoE-deficient mice is caused by the inhibition of an as yet uncharacterized apoE-independent mechanism of removal of remnant from the circulation by the liver.

scholarly journals Dietary Flaxseed Oil Prevents Western-Type Diet-Induced Nonalcoholic Fatty Liver Disease in Apolipoprotein-E Knockout Mice

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Hao Han ◽  
Fubin Qiu ◽  
Haifeng Zhao ◽  
Haiying Tang ◽  
Xiuhua Li ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Disease ◽  
Fatty Liver ◽  
Apolipoprotein E ◽  
Nonalcoholic Fatty Liver Disease ◽  
Fatty Liver Disease ◽  
Flaxseed Oil ◽  
Chow Diet ◽  
Nonalcoholic Fatty Liver ◽  
Apolipoprotein E Knockout Mice

The prevalence of nonalcoholic fatty liver disease (NAFLD) has dramatically increased globally during recent decades. Intake of n-3 polyunsaturated fatty acids (PUFAs), mainly eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3), is believed to be beneficial to the development of NAFLD. However, little information is available with regard to the effect of flaxseed oil rich in α-linolenic acid (ALA, C18:3n-3), a plant-derived n-3 PUFA, in improving NAFLD. This study was to gain the effect of flaxseed oil on NAFLD and further investigate the underlying mechanisms. Apolipoprotein-E knockout (apoE-KO) mice were given a normal chow diet, a western-type high-fat and high-cholesterol diet (WTD), or a WTD diet containing 10% flaxseed oil (WTD + FO) for 12 weeks. Our data showed that consumption of flaxseed oil significantly improved WTD-induced NAFLD, as well as ameliorated impaired lipid homeostasis, attenuated oxidative stress, and inhibited inflammation. These data were associated with the modification effects on expression levels of genes involved in de novo fat synthesis (SREBP-1c, ACC), triacylglycerol catabolism (PPARα, CPT1A, and ACOX1), inflammation (NF-κB, IL-6, TNF-α, and MCP-1), and oxidative stress (ROS, MDA, GSH, and SOD).

scholarly journals Diminazene Aceturate Stabilizes Atherosclerotic Plaque and Attenuates Hepatic Steatosis in apoE-Knockout Mice by Influencing Macrophages Polarization and Taurine Biosynthesis

2021 ◽  
Vol 22 (11) ◽  
pp. 5861
Author(s):  
Aneta Stachowicz ◽  
Anna Wiśniewska ◽  
Katarzyna Kuś ◽  
Magdalena Białas ◽  
Magdalena Łomnicka ◽  
...  
Keyword(s):  
Hepatic Steatosis ◽  
Molecular Mechanisms ◽  
Smooth Muscle Actin ◽  
Renin Angiotensin System ◽  
Prolonged Treatment ◽  
Ang Ii ◽  
Diminazene Aceturate ◽  
Nonalcoholic Fatty Liver ◽  
Atherosclerotic Lesions ◽  
Apoe Knockout Mice

Atherosclerosis and nonalcoholic fatty liver disease are leading causes of morbidity and mortality in the Western countries. The renin–angiotensin system (RAS) with its two main opposing effectors, i.e., angiotensin II (Ang II) and Ang-(1–7), is widely recognized as a major regulator of cardiovascular function and body metabolic processes. Angiotensin-converting enzyme 2 (ACE2) by breaking-down Ang II forms Ang-(1–7) and thus favors Ang-(1–7) actions. Therefore, the aim of our study was to comprehensively evaluate the influence of prolonged treatment with ACE2 activator, diminazene aceturate (DIZE) on the development of atherosclerotic lesions and hepatic steatosis in apoE−/− mice fed a high-fat diet (HFD). We have shown that DIZE stabilized atherosclerotic lesions and attenuated hepatic steatosis in apoE−/− mice fed an HFD. Such effects were associated with decreased total macrophages content and increased α-smooth muscle actin levels in atherosclerotic plaques. Moreover, DIZE changed polarization of macrophages towards increased amount of anti-inflammatory M2 macrophages in the atherosclerotic lesions. Interestingly, the anti-steatotic action of DIZE in the liver was related to the elevated levels of HDL in the plasma, decreased levels of triglycerides, and increased biosynthesis and concentration of taurine in the liver of apoE−/− mice. However, exact molecular mechanisms of both anti-atherosclerotic and anti-steatotic actions of DIZE require further investigations.

scholarly journals Fat Mass and Obesity–Associated Protein Promotes Liver Steatosis By Targeting PPARα

2022 ◽  
Author(s):  
Xiaohui Wei ◽  
Jielei Zhang ◽  
Min Tang ◽  
Xuejiao Wang ◽  
Nengguang Fan ◽  
...  
Keyword(s):  
Liver Disease ◽  
Hepatic Steatosis ◽  
Fat Mass ◽  
Lipid Accumulation ◽  
Molecular Mechanisms ◽  
Liver Steatosis ◽  
Peroxisome Proliferator ◽  
Cellular Models ◽  
Triglyceride Accumulation

Abstract Background: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. The fat mass and obesity–associated protein (FTO) has been shown to be involved in obesity; however, its role in NAFLD and the underlying molecular mechanisms remain largely unknown. Methods: FTO expression was first examined in the livers of patients with NAFLD and animal and cellular models of NAFLD using quantitative real-time polymerase chain reaction and western blotting. Next, its role in lipid accumulation in hepatocytes was assessed both in vitro and in vivo via gene overexpression and knockdown studies. Results: FTO expression was increased in the livers of mice and humans with hepatic steatosis, probably due to its decreased ubiquitination. FTO overexpression in HepG2 cells induced triglyceride accumulation, whereas FTO knockdown exerted an opposing effect. Consistent with the findings of in vitro studies, adeno-associated viruses 8 (AAV8)-mediated FTO overexpression in the liver promoted hepatic steatosis in C57BL/6J mice. Mechanistically, FTO inhibited the mRNA expression of peroxisome proliferator-activated receptor α (PPARα) in hepatocytes. Activation of PPARα by the PPARα agonist GW7647 reversed lipid accumulation in hepatocytes induced by FTO overexpression.Conclusions: Overall, FTO expression is increased in NAFLD, and it promotes hepatic steatosis by targeting PPARα.

Sign in / Sign up

Export Citation Format

Share Document