scholarly journals Stable Isotope-Labeled Lipidomics to Unravel the Heterogeneous Development Lipotoxicity

Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2862 ◽  
Author(s):  
Lu-Min Shih ◽  
Hsiang-Yu Tang ◽  
Ke-Shiuan Lynn ◽  
Cheng-Yu Huang ◽  
Hung-Yao Ho ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Lipid Metabolism ◽  
Stable Isotope ◽  
Fatty Liver ◽  
Lipid Droplet ◽  
De Novo ◽  
Clinical Manifestations ◽  
Lipid Profiles ◽  
Alcoholic Fatty Liver ◽  
Hepatic Lipotoxicity

Non-alcoholic fatty liver disease (NAFLD) as a global health problem has clinical manifestations ranging from simple non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH), cirrhosis, and cancer. The role of different types of fatty acids in driving the early progression of NAFL to NASH is not understood. Lipid overload causing lipotoxicity and inflammation has been considered as an essential pathogenic factor. To correlate the lipid profiles with cellular lipotoxicity, we utilized palmitic acid (C16:0)- and especially unprecedented palmitoleic acid (C16:1)-induced lipid overload HepG2 cell models coupled with lipidomic technology involving labeling with stable isotopes. C16:0 induced inflammation and cell death, whereas C16:1 induced significant lipid droplet accumulation. Moreover, inhibition of de novo sphingolipid synthesis by myriocin (Myr) aggravated C16:0 induced lipoapoptosis. Lipid profiles are different in C16:0 and C16:1-treated cells. Stable isotope-labeled lipidomics elucidates the roles of specific fatty acids that affect lipid metabolism and cause lipotoxicity or lipid droplet formation. It indicates that not only saturation or monounsaturation of fatty acids plays a role in hepatic lipotoxicity but also Myr inhibition exasperates lipoapoptosis through ceramide in-direct pathway. Using the techniques presented in this study, we can potentially investigate the mechanism of lipid metabolism and the heterogeneous development of NAFLD.

scholarly journals Metabolic and Genetic Determinants of Lipid Metabolism Disruption in Non-Alcoholic Fatty Liver Disease

2020 ◽  
Vol 30 (2) ◽  
pp. 15-25
Author(s):  
O. Yu. Kytikova ◽  
T. P. Novgorodtseva ◽  
Yu. K. Denisenko ◽  
D. A. Kovalevsky
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Fatty Acid Desaturases ◽  
Alcoholic Fatty Liver ◽  
Genetic Mechanisms ◽  
Alcoholic Fatty Liver Disease

Aim. To present literature data on the metabolic and genetic mechanisms of impaired fatty acid (FA) synthesis in the development and progression of non-alcoholic fatty liver disease (NAFLD).General findings. NAFLD is a widespread disease progressing from steatosis to non-alcoholic steatohepatitis (NASH), increasing the risk of cirrhosis, liver failure and hepatocellular carcinoma. Progression of NAFLD and the development of NASH are closely related to lipid metabolism disorders caused not only by insufficient alimentary intake of fatty acids, but also by a decrease in the efficiency of their endogenous processing. The regulation of fatty acid metabolism involves enzymes desaturase (FADS1, FADS2) and elongase (ELOVL2 and ELOVL5) fatty acids. Desaturases are encoded by the FADS1 and FADS2 genes for fatty acid desaturases. Polymorphisms in the genes of fatty acid desaturases determine the effectiveness of PUFA endogenous processing. Violations in the activity of FADS1 and FADS2 and their genes are accompanied by dysregulation of the metabolic pathway involved in the biosynthesis of fatty acids. This leads to the damage of cell membranes, whose main components are represented by phospholipids. The progression of NAFLD is associated with the powerful toxicity of lipids released in the liver parenchyma upon the loss of the cell biomembrane integrity.Conclusions. Further research into the NAFLD genetic mechanisms regulating the metabolism of fatty acids appears to be promising for a deeper understanding of the pathogenesis of this multifactorial disease.

scholarly journals Non-alcoholic fatty liver disease (NAFLD) – epidemic of the XXI century

2018 ◽  
Vol 72 ◽  
pp. 659-670 ◽  
Author(s):  
Dominika Maciejewska ◽  
Ewa Stachowska
Keyword(s):  
Insulin Resistance ◽  
Fatty Acids ◽  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
De Novo ◽  
Serum Insulin ◽  
De Novo Lipogenesis ◽  
Alcoholic Fatty Liver ◽  
Alcoholic Fatty Liver Disease

The term “non-alcoholic fatty liver disease” (NAFLD) was first introduced by Ludwig in 1980. He described NAFLD as a liver disease characterized by lipid accumulation in the hepatocytes of people who do not abuse alcohol (<20g/ethanol/day). NAFLD comprises of a range of disorders, including simple fatty liver without the symptoms of damaged hepatocytes, as well as complex fatty liver with an ongoing inflammation and developing fibrosis. It is estimated that 2-44% of adult Europeans will develop a fatty liver. The pathogenesis and development of NAFLD is a complicated process involving numerous factors, such as: dyslipidemia, insulin resistance, overweight, obesity, mitochondrial dysfunction, oxidative stress, the development of an inflammatory state, the disorders of the metabolism of fat tissue, dysbiosis and genetic factors. Because the mechanism of the illness is based on many factors, the multiple hits hypothesis serves as the new and generally standard approach to this pathological unit. The basis of this theory is the development of insulin resistance, which is one of the main causes of steatosis. The consequence of insulin resistance is an increased glucose level (associated with impaired insulin receptors) and excessive insulin production leading to elevated levels of this hormone in the serum. Insulin resistance causes continuous stimulation of gluconeogenesis and hyperglycemia. On the other hand, hyperinsulinemia stimulates the hepatic synthesis of the de novo lipogenesis and leads to steatosis. NAFLD is also closely connected to the metabolism disorders of fatty acids. The pathomechanism of the illness includes an increased concentration of FFA in blood, an increase in the biosynthesis of fatty acids in the liver, as well as disorders in the process of β-oxidation.

Withdrawn: Hepatoprotective effects of Tribulus terrestris L. (Zygophyllales: Zygophyllaceae) hydro-alcholic extract on non-alcoholic fatty liver-induced rats

2016 ◽  
Vol 3 (5) ◽  
pp. 143
Author(s):  
Fatemeh Almasi ◽  
Mozafar Khazaei ◽  
Shima Chehrei ◽  
Ali Ghanbari
Keyword(s):  
Fatty Liver ◽  
Liver Tissue ◽  
Serum Lipid ◽  
Histopathological Examination ◽  
Serum Levels ◽  
Lipid Profiles ◽  
Control Group ◽  
Tribulus Terrestris ◽  
Protective Effects ◽  
Alcoholic Fatty Liver

Non-alcoholic fatty liver induces many complications to the liver tissue and also serum related parameters. Medicinal plants are the safe therapeutic strategy for the treatment of diseases. In this regards, the present study was conducted to evaluate the effect of Tribulus terrestris L. (Zygophyllales: Zygophyllaceae) extract on non-alcoholic fatty liver in rats. In this experimental study, thirty male Wistar rats were divided into five groups (n = 6). Animals in experimental groups were received high fructose diet (70%) (HDF) daily alone or in combined with daily intraperitoneal injection of 500, 700 and 1,000 mg/kg extract of T. terrestris. Control group of rats was feed with standard chow. The serum levels of biomarkers of liver and serum lipid profiles were assessed, also histopathological examination of liver tissue done. Data were analyzed using One-way ANOVA method followed by Tukey’s post-hoc multiple comparison test and P < 0.05 was considered statistically significant. There were significant improvements for biomarkers of liver tissue (P < 0.05) and serum lipid profiles (P < 0.01) in the HFD-fed rats that were treated with T. terrestris extract compare to HFD-fed group. In addition, accumulation of lipids in hepatocytes was significantly reduced in the HFD-fed + extract administrated groups in comparison to HFD-fed rats (P < 0.01). T. terrestris extract has protective effects against non-alcoholic fatty liver by changing biomarkers of liver tissue, serum lipid profiles and histopathological anomalies of liver tissue, to normal range.

The correlation between lipid metabolism disorders and the prostate cancer

2020 ◽  
Vol 27 ◽  
Author(s):  
Justyna Dłubek ◽  
Jacek Rysz ◽  
Zbigniew Jabłonowski ◽  
Anna Gluba-Brzózka ◽  
Beata Franczyk
Keyword(s):  
Prostate Cancer ◽  
Fatty Acids ◽  
Lipid Metabolism ◽  
Cancer Progression ◽  
De Novo ◽  
Prostate Gland ◽  
Hdl Cholesterol ◽  
Atp Citrate Lyase ◽  
Male Population ◽  
Lipid Metabolism Disorders

: Prostate cancer is second most common cancer affecting male population all over the world. The existence of a correlation between lipid metabolism disorders and cancer of the prostate gland has been widely known for a long time. According to hypotheses, cholesterol may contribute to prostate cancer progression as a result of its participation as a signalling molecule in prostate growth and differentiation via numerous biologic mechanisms including Akt signalling and de novo steroidogenesis. The results of some studies suggest that increased cholesterol levels may be associated with higher risk of more aggressive course of disease. The aforementioned alterations in the synthesis of fatty acids are a unique feature of cancer and, therefore, it constitutes an attractive target for therapeutic intervention in the treatment of prostate cancer. Pharmacological or gene therapy aimed to reduce the activity of enzymes involved in de novo synthesis of fatty acids, FASN, ACLY (ATP citrate lyase) or SCD-1 (stearoyl-CoA desaturase) in particular, may result in cells growth arrest. Nevertheless, not all cancers are unequivocally associated with hypocholesterolaemia. It cannot be ruled out that the relationship between prostate cancer and lipid disorders is not a direct quantitative correlation between carcinogenesis and the amount of the circulating cholesterol. Perhaps the correspondence is more sophisticated and connected to the distribution of cholesterol fractions, or even sub-fractions of e.g. HDL cholesterol.

scholarly journals How does hepatic lipid accumulation lead to lipotoxicity in non-alcoholic fatty liver disease?

2021 ◽  
Vol 15 (1) ◽  
pp. 21-35
Author(s):  
Yana Geng ◽  
Klaas Nico Faber ◽  
Vincent E. de Meijer ◽  
Hans Blokzijl ◽  
Han Moshage
Keyword(s):  
Lipid Metabolism ◽  
Liver Disease ◽  
Fatty Liver ◽  
Lipid Accumulation ◽  
Fatty Liver Disease ◽  
Lipid Uptake ◽  
Cellular Mechanisms ◽  
Alcoholic Fatty Liver ◽  
Lipid Species ◽  
Alcoholic Fatty Liver Disease

Abstract Background Non-alcoholic fatty liver disease (NAFLD), characterized as excess lipid accumulation in the liver which is not due to alcohol use, has emerged as one of the major health problems around the world. The dysregulated lipid metabolism creates a lipotoxic environment which promotes the development of NAFLD, especially the progression from simple steatosis (NAFL) to non-alcoholic steatohepatitis (NASH). Purposeand Aim This review focuses on the mechanisms of lipid accumulation in the liver, with an emphasis on the metabolic fate of free fatty acids (FFAs) in NAFLD and presents an update on the relevant cellular processes/mechanisms that are involved in lipotoxicity. The changes in the levels of various lipid species that result from the imbalance between lipolysis/lipid uptake/lipogenesis and lipid oxidation/secretion can cause organellar dysfunction, e.g. ER stress, mitochondrial dysfunction, lysosomal dysfunction, JNK activation, secretion of extracellular vesicles (EVs) and aggravate (or be exacerbated by) hypoxia which ultimately lead to cell death. The aim of this review is to provide an overview of how abnormal lipid metabolism leads to lipotoxicity and the cellular mechanisms of lipotoxicity in the context of NAFLD.

scholarly journals A Narrative Review on the Role of AMPK on De Novo Lipogenesis in Non-Alcoholic Fatty Liver Disease: Evidence from Human Studies

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1822
Author(s):  
Christian von Loeffelholz ◽  
Sina M. Coldewey ◽  
Andreas L. Birkenfeld
Keyword(s):  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Mammalian Cells ◽  
De Novo ◽  
Adenosine Monophosphate ◽  
De Novo Lipogenesis ◽  
Alcoholic Fatty Liver ◽  
Alcoholic Fatty Liver Disease

5′AMP-activated protein kinase (AMPK) is known as metabolic sensor in mammalian cells that becomes activated by an increasing adenosine monophosphate (AMP)/adenosine triphosphate (ATP) ratio. The heterotrimeric AMPK protein comprises three subunits, each of which has multiple phosphorylation sites, playing an important role in the regulation of essential molecular pathways. By phosphorylation of downstream proteins and modulation of gene transcription AMPK functions as a master switch of energy homeostasis in tissues with high metabolic turnover, such as the liver, skeletal muscle, and adipose tissue. Regulation of AMPK under conditions of chronic caloric oversupply emerged as substantial research target to get deeper insight into the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Evidence supporting the role of AMPK in NAFLD is mainly derived from preclinical cell culture and animal studies. Dysbalanced de novo lipogenesis has been identified as one of the key processes in NAFLD pathogenesis. Thus, the scope of this review is to provide an integrative overview of evidence, in particular from clinical studies and human samples, on the role of AMPK in the regulation of primarily de novo lipogenesis in human NAFLD.

Sign in / Sign up

Export Citation Format

Share Document