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Lu J, Chen Z, Bu X, Chen S, Guan S. Elaidic acid induced hepatocyte pyroptosis via autophagy-CTSB-NLRP3 pathway. Food Chem Toxicol 2023; 181:114060. [PMID: 37748573 DOI: 10.1016/j.fct.2023.114060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 09/27/2023]
Abstract
Elaidic acid (EA, C18:1 trans) is a kind of principal Trans fatty acid (TFA) and is widely found in processed food. Pyroptosis is a form of programmed cell death, distinct from apoptosis and traditional necrosis. Excessive pyroptosis could induce body injury and serious inflammation. However, the effect of EA on pyroptosis has not been reported. In the study, we found that EA exposure caused liver damage and hepatocyte pyroptosis by testing GSDMD-N, Caspase 1, IL-18, and IL-1β in mice and HepG2 cells. Further exploring the mechanisms, we found that EA-induced pyroptosis depended on Cathepsin B (CTSB)-mediated NLRP3 inflammasome activation. Cell autophagy was closely related to lysosomes. Our study revealed that EA promoted hepatocyte autophagy, and activated autophagy induced lysosomal membrane permeabilization (LMP) and CTSB leakage. Inhibition of autophagy by 3-MA mitigated the CTSB leak, reduced the activation of the NLRP3 inflammasome, and then attenuated the EA-induced pyroptosis. In summary, these results indicated that EA induced hepatocyte pyroptosis via autophagy-CTSB-NLRP3 inflammasome pathway. The study revealed new insights into the toxicity mechanism of EA.
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Affiliation(s)
- Jing Lu
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, 130062, People's Republic of China
| | - Ziheng Chen
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, 130062, People's Republic of China
| | - Xiujuan Bu
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, 130062, People's Republic of China
| | - Shanshan Chen
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, 130062, People's Republic of China
| | - Shuang Guan
- College of Food Science and Engineering, Jilin University, Changchun, Jilin, 130062, People's Republic of China; Key Laboratory of Zoonosis, Ministry of Education College of Veterinary Medicine, Jilin University, Changchun, Jilin, 130062, People's Republic of China.
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Maternal conjugated linoleic acid consumption prevented TAG alterations induced by a high-fat diet in male adult rat offspring. Br J Nutr 2020; 124:286-295. [PMID: 32234086 DOI: 10.1017/s0007114520001166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Maternal nutritional programming by a high-fat (HF) diet is related to hepatic lipid accumulation and steatosis in offspring. Conjugated linoleic acid (CLA) might ameliorate impaired hepatic lipid homoeostasis; therefore, the aim was to investigate the potential preventive effect of maternal CLA consumption on TAG metabolism alterations induced by HF diets in adult male rat offspring receiving or not receiving CLA. Female Wistar rats were fed a control (C) diet, HF diet or HF diet supplemented with CLA (HF+CLA) for 4 weeks before mating and throughout pregnancy and lactation. After weaning, for 9 weeks, male offspring of C or HF rats continued with the same diets as their mothers (C/C or HF/HF groups, respectively) and male offspring of HF+CLA rats were fed HF or HF+CLA diets (HF+CLA/HF or HF+CLA/HF+CLA groups, respectively). Nutritional parameters, serum and liver TAG levels, the TAG secretion rate (TAG-SR) and the activities as well as gene expression of key hepatic enzymes involved in TAG regulation were assessed. The most interesting results were that maternal CLA decreased epididymal white adipose tissue weight and prevented serum and liver TAG accumulation induced by a HF diet in adult male offspring receiving or not receiving CLA. The prevention of liver steatosis in HF+CLA/HF+CLA and HF+CLA/HF offspring was associated with an increased hepatic TAG-SR. Overall, this study provides evidence that maternal CLA consumption programmes TAG regulation and in this way contributes to lowering lipid levels in tissues and preventing liver steatosis in particular.
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Drescher HK, Weiskirchen R, Fülöp A, Hopf C, de San Román EG, Huesgen PF, de Bruin A, Bongiovanni L, Christ A, Tolba R, Trautwein C, Kroy DC. The Influence of Different Fat Sources on Steatohepatitis and Fibrosis Development in the Western Diet Mouse Model of Non-alcoholic Steatohepatitis (NASH). Front Physiol 2019; 10:770. [PMID: 31293441 PMCID: PMC6603084 DOI: 10.3389/fphys.2019.00770] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 06/03/2019] [Indexed: 12/19/2022] Open
Abstract
Non-alcoholic steatohepatitis (NASH) is the leading cause of chronic liver injury and the third most common reason for liver transplantations in Western countries. It is unclear so far how different fat sources in Western diets (WD) influence the development of NASH. Our study investigates the impact of non-trans fat (NTF) and corn oil (Corn) as fat source in a WD mouse model of steatohepatitis on disease development and progression. C57BL/6J wildtype (WT) mice were fed “standard” WD (WD-Std), WD-NTF or WD-Corn for 24 weeks. WT animals treated with WD-NTF exhibit distinct features of the metabolic syndrome compared to WD-Std and WD-Corn. This becomes evident by a worsened insulin resistance and elevated serum ALT, cholesterol and triglyceride (TG) levels compared to WD-Corn. Animals fed WD-Corn on the contrary tend to a weakened disease progression in the described parameters. After 24 weeks feeding with WD-NTF and WD-Std, WD-Corn lead to a comparable steatohepatitis initiation by histomorphological changes and immune cell infiltration compared to WD-Std. Immune cell infiltration results in a significant increase in mRNA expression of the pro-inflammatory cytokines IL-6 and TNF-α, which is more pronounced in WD-NTF compared to WD-Std and WD-Corn. Interestingly the fat source has no impact on the composition of accumulating fat within liver tissue as determined by matrix-assisted laser desorption/ionization mass spectrometry imaging of multiple lipid classes. The described effects of different fat sources on the development of steatohepatitis finally resulted in variations in fibrosis development. Animals treated with WD-NTF displayed massive collagen accumulation, whereas WD-Corn even seems to protect from extracellular matrix deposition. Noteworthy, WD-Corn provokes massive histomorphological modifications in epididymal white adipose tissue (eWAT) and severe accumulation of extracellular matrix which are not apparent in WD-Std and WD-NTF treatment. Different fat sources in WD-Std contribute to strong steatohepatitis development in WT mice after 24 weeks treatment. Surprisingly, corn oil provokes histomorphological changes in eWAT tissue. Accordingly, both WD-NTF and WD-Corn appear suitable as alternative dietary treatment to replace “standard” WD-Std as a diet mouse model of steatohepatitis whereas WD-Corn leads to strong changes in eWAT morphology.
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Affiliation(s)
- Hannah K Drescher
- Department of Internal Medicine III, University Hospital RWTH Aachen, Aachen, Germany
| | - Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), University Hospital RWTH Aachen, Aachen, Germany
| | - Annabelle Fülöp
- Center for Biomedical Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany
| | - Carsten Hopf
- Center for Biomedical Mass Spectrometry and Optical Spectroscopy (CeMOS), Mannheim University of Applied Sciences, Mannheim, Germany
| | | | - Pitter F Huesgen
- Central Institute for Engineering, Electronics and Analytics, ZEA-3 - Forschungszentrum Jülich, Jülich, Germany
| | - Alain de Bruin
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Laura Bongiovanni
- Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Annette Christ
- Institute of Innate Immunity, University Hospital Bonn, Bonn, Germany.,Department of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, United States
| | - René Tolba
- Institute of Laboratory Animal Science and Experimental Surgery and Central Laboratory for Laboratory Animal Science, University Hospital RWTH Aachen, Aachen, Germany
| | - Christian Trautwein
- Department of Internal Medicine III, University Hospital RWTH Aachen, Aachen, Germany
| | - Daniela C Kroy
- Department of Internal Medicine III, University Hospital RWTH Aachen, Aachen, Germany
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The effects of trans-fatty acids on TAG regulation in mice depend on dietary unsaturated fatty acids. Br J Nutr 2017; 116:611-20. [PMID: 27464460 DOI: 10.1017/s0007114516002415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The aim of this study was to investigate the effects of trans-fatty acids (TFA) on liver and serum TAG regulation in mice fed diets containing different proportions of n-3, n-6 and n-9 unsaturated fatty acids (UFA) from olive (O), maize (C) or rapeseed (R) oils partially substituted or not with TFA (Ot, Ct and Rt, respectively). Male CF1 mice were fed (30 d) one of these diets. The effects of the partial substitution (1 %, w/w) of different UFA with TFA on the activity and expression of hepatic enzymes involved in lipogenesis and fatty acids oxidation were evaluated, as well as their transcription factor expressions. Some of the mechanisms involved in the serum TAG regulation, hepatic VLDL rich in TAG (VLDL-TAG) secretion rate and lipoprotein lipase (LPL) activity were assessed. In liver, TFA induced an increase in TAG content in the Ot and Rt groups, and this effect was associated with an imbalance between lipogenesis and β-oxidation. In the Ot group, exacerbated lipogenesis may be one of the mechanisms responsible for the liver steatosis induced by TFA, whereas in Rt it has been related to a decreased β-oxidation, compared with their respective controls. The enhanced hepatic VLDL-TAG secretion in the Ot and Rt groups was compensated with a differential removal of TAG by LPL enzyme in extrahepatic tissues, leading to unchanged serum TAG levels. In brief, the effects of low levels of TFA on liver and serum TAG regulation in mice depend on the dietary proportions of n-3, n-6 and n-9 UFA.
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Rodrigues HG, Vinolo MAR, Sato FT, Magdalon J, Kuhl CMC, Yamagata AS, Pessoa AFM, Malheiros G, dos Santos MF, Lima C, Farsky SH, Camara NOS, Williner MR, Bernal CA, Calder PC, Curi R. Oral Administration of Linoleic Acid Induces New Vessel Formation and Improves Skin Wound Healing in Diabetic Rats. PLoS One 2016; 11:e0165115. [PMID: 27764229 PMCID: PMC5072690 DOI: 10.1371/journal.pone.0165115] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 10/06/2016] [Indexed: 12/28/2022] Open
Abstract
Introduction Impaired wound healing has been widely reported in diabetes. Linoleic acid (LA) accelerates the skin wound healing process in non-diabetic rats. However, LA has not been tested in diabetic animals. Objectives We investigated whether oral administration of pure LA improves wound healing in streptozotocin-induced diabetic rats. Methods Dorsal wounds were induced in streptozotocin-induced type-1 diabetic rats treated or not with LA (0.22 g/kg b.w.) for 10 days. Wound closure was daily assessed for two weeks. Wound tissues were collected at specific time-points and used to measure fatty acid composition, and contents of cytokines, growth factors and eicosanoids. Histological and qPCR analyses were employed to examine the dynamics of cell migration during the healing process. Results LA reduced the wound area 14 days after wound induction. LA also increased the concentrations of cytokine-induced neutrophil chemotaxis (CINC-2αβ), tumor necrosis factor-α (TNF-α) and leukotriene B4 (LTB4), and reduced the expression of macrophage chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1 (MIP-1). These results together with the histological analysis, which showed accumulation of leukocytes in the wound early in the healing process, indicate that LA brought forward the inflammatory phase and improved wound healing in diabetic rats. Angiogenesis was induced by LA through elevation in tissue content of key mediators of this process: vascular-endothelial growth factor (VEGF) and angiopoietin-2 (ANGPT-2). Conclusions Oral administration of LA hastened wound closure in diabetic rats by improving the inflammatory phase and angiogenesis.
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Affiliation(s)
- Hosana G. Rodrigues
- School of Applied Sciences, University of Campinas, Limeira, Brazil
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
- * E-mail:
| | - Marco A. R. Vinolo
- Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Fabio T. Sato
- Department of Genetics, Evolution and Bioagents, Institute of Biology, University of Campinas, Campinas, Brazil
| | - Juliana Magdalon
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | | | - Ana S. Yamagata
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Ana Flávia M. Pessoa
- Cell and Developmental Biology Department, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Gabriella Malheiros
- Cell and Developmental Biology Department, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Marinilce F. dos Santos
- Cell and Developmental Biology Department, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Camila Lima
- Department of Clinical and Toxicology Analyses, School of Pharmaceutical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Sandra H. Farsky
- Department of Clinical and Toxicology Analyses, School of Pharmaceutical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Niels O. S. Camara
- Department of Immunology, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
| | - Maria R. Williner
- Food Sciences and Nutrition, School of Biochemistry and Biological Sciences, National University of Litoral, Santa Fé, Argentina
| | - Claudio A. Bernal
- Food Sciences and Nutrition, School of Biochemistry and Biological Sciences, National University of Litoral, Santa Fé, Argentina
| | - Philip C. Calder
- Human Development and Health Academic Unit, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust and University of Southampton, Southampton, United Kingdom
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, Sao Paulo University, Sao Paulo, Brazil
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Lavandera JV, Saín J, Fariña AC, Bernal CA, González MA. N-3 fatty acids reduced trans fatty acids retention and increased docosahexaenoic acid levels in the brain. Nutr Neurosci 2016; 20:424-435. [PMID: 27098669 DOI: 10.1080/1028415x.2016.1173343] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION The levels of docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are critical for the normal structure and function of the brain. Trans fatty acids (TFA) and the source of the dietary fatty acids (FA) interfere with long-chain polyunsaturated fatty acids (LC-PUFA) biosynthesis. OBJECTIVES The aim of this study was to investigate the effect of TFA supplementation in diets containing different proportions of n-9, n-6, and n-3 FA on the brain FA profile, including the retention of TFA, LC-PUFA levels, and n-6/n-3 PUFA ratios. These parameters were also investigated in the liver, considering that LC-PUFA are mainly bioconverted from their dietary precursors in this tissue and transported by serum to the brain. Also, stearoyl-CoA desaturase-1 (SCD1) and sterol regulatory element-binding protein-1c (SREBP-1c) gene expressions were evaluated. METHODS Male CF1 mice were fed (16 weeks) diets containing different oils (olive, corn, and rapeseed) with distinct proportions of n-9, n-6, and n-3 FA (55.2/17.2/0.7, 32.0/51.3/0.9, and 61.1/18.4/8.6), respectively, substituted or not with 0.75% of TFA. FA composition of the brain, liver, and serum was assessed by gas chromatography. RESULTS TFA were incorporated into, and therefore retained in the brain, liver, and serum. However, the magnitude of retention was dependent on the tissue and type of isomer. In the brain, total TFA retention was lower than 1% in all diets. DISCUSSION Dietary n-3 PUFA decreased TFA retention and increased DHA accretion in the brain. The results underscore the importance of the type of dietary FA on the retention of TFA in the brain and also on the changes of the FA profile.
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Affiliation(s)
- Jimena Verónica Lavandera
- a Cátedra de Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas , Universidad Nacional del Litoral , Santa Fe , Argentina.,b Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) , Santa Fe , Argentina
| | - Juliana Saín
- a Cátedra de Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas , Universidad Nacional del Litoral , Santa Fe , Argentina.,b Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) , Santa Fe , Argentina
| | - Ana Clara Fariña
- a Cátedra de Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas , Universidad Nacional del Litoral , Santa Fe , Argentina
| | - Claudio Adrián Bernal
- a Cátedra de Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas , Universidad Nacional del Litoral , Santa Fe , Argentina.,b Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) , Santa Fe , Argentina
| | - Marcela Aída González
- a Cátedra de Bromatología y Nutrición, Facultad de Bioquímica y Ciencias Biológicas , Universidad Nacional del Litoral , Santa Fe , Argentina
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Effect of a trans fatty acid-enriched diet on biochemical and inflammatory parameters in Wistar rats. Eur J Nutr 2016; 56:1003-1016. [PMID: 26754301 DOI: 10.1007/s00394-015-1148-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 12/22/2015] [Indexed: 12/17/2022]
Abstract
PURPOSE Recent data regarding trans fatty acids (TFAs) have implicated these lipids as particularly deleterious to human health, causing systemic inflammation, endothelial dysfunction and possibly inflammation in the central nervous system (CNS). We aimed to clarify the impact of partially hydrogenated soybean oil (PHSO) with different TFA concentrations on cerebrospinal fluid (CSF), serum and hepatic parameters in adult Wistar rats. METHODS Wistar rats (n = 15/group) were fed either a normolipidic diet or a hyperlipidic diet for 90 days. The normolipidic and hyperlipidic diets had the same ingredients except for fat compositions, concentrations and calories. We used lard in the cis fatty acid group and PHSO in the trans fatty acid group. The intervention groups were as follows: (1) low lard (LL), (2) high lard (HL), (3) low partially hydrogenated soybean oil (LPHSO) and (4) high partially hydrogenated soybean oil (HPHSO). Body weight, lipid profiles and the inflammatory responses in the CSF, serum and liver tissue were analyzed. RESULTS Surprisingly, with the PHSO diet we observed a worse metabolic response that was associated with oxidative stress in hepatic tissue as well as impaired serum and CSF fluid parameters at both PHSO concentrations. In many analyses, there were no significant differences between the LPHSO and HPHSO diets. CONCLUSIONS Dietary supplementation with PHSO impaired inflammatory parameters in CSF and blood, induced insulin resistance, altered lipid profiles and caused hepatic damage. Overall, these findings suggest that fat composition is more important than the quantity of fat consumed in terms of cis and trans fatty acid diets.
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Saín J, González MA, Lavandera JV, Scalerandi MV, Bernal CA. Trans
fatty acid retention and conversion rates of fatty acids in tissues depend on dietary fat in mice. EUR J LIPID SCI TECH 2015. [DOI: 10.1002/ejlt.201400287] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Juliana Saín
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
| | - Marcela Aída González
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
| | - Jimena Verónica Lavandera
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
| | - María Victoria Scalerandi
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
| | - Claudio Adrián Bernal
- Cátedra de Bromatología y NutriciónFacultad de Bioquímica y Ciencias BiológicasUniversidad Nacional del LitoralSanta FeArgentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Santa FeArgentina
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Zámbó V, Simon-Szabó L, Szelényi P, Kereszturi &E, Bánhegyi G, Csala M. Lipotoxicity in the liver. World J Hepatol 2013; 5:550-557. [PMID: 24179614 PMCID: PMC3812457 DOI: 10.4254/wjh.v5.i10.550] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 09/27/2013] [Accepted: 10/16/2013] [Indexed: 02/06/2023] Open
Abstract
Obesity due to excessive food intake and the lack of physical activity is becoming one of the most serious public health problems of the 21st century. With the increasing prevalence of obesity, non-alcoholic fatty liver disease is also emerging as a pandemic. While previously this pathophysiological condition was mainly attributed to triglyceride accumulation in hepatocytes, recent data show that the development of oxidative stress, lipid peroxidation, cell death, inflammation and fibrosis are mostly due to accumulation of fatty acids, and the altered composition of membrane phospholipids. In fact, triglyceride accumulation might play a protective role, and the higher toxicity of saturated or trans fatty acids seems to be the consequence of a blockade in triglyceride synthesis. Increased membrane saturation can profoundly disturb cellular homeostasis by impairing the function of membrane receptors, channels and transporters. However, it also induces endoplasmic reticulum stress via novel sensing mechanisms of the organelle’s stress receptors. The triggered signaling pathways in turn largely contribute to the development of insulin resistance and apoptosis. These findings have substantiated the lipotoxic liver injury hypothesis for the pathomechanism of hepatosteatosis. This minireview focuses on the metabolic and redox aspects of lipotoxicity and lipoapoptosis, with special regards on the involvement of endoplasmic reticulum stress responses.
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