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Induction of microRNA hsa-let-7d-5p, and repression of HMGA2, contribute protection against lipid accumulation in macrophage 'foam' cells. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159005. [PMID: 34274506 DOI: 10.1016/j.bbalip.2021.159005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/08/2021] [Accepted: 07/13/2021] [Indexed: 12/14/2022]
Abstract
Accumulation of excess cholesterol and cholesteryl ester in macrophage 'foam' cells within the arterial intima characterises early 'fatty streak' atherosclerotic lesions, and is accompanied by epigenetic changes, including altered expression of microRNA sequences which determine of gene and protein expression. This study established that exposure to lipoproteins, including acetylated LDL, induced macrophage expression of microRNA hsa-let-7d-5p, a sequence previously linked with tumour suppression, and repressed expression of one of its target genes, high mobility group AT hook 2 (HMGA2). A let-7d-5p mimic repressed expression of HMGA2 (18%; p < 0.05) while a marked increase (2.9-fold; p < 0.05) in expression of HMGA2 was noted in the presence of let-7d-5p inhibitor. Under these conditions, let-7d-5p mimic significantly (p < 0.05) decreased total (10%), free (8%) and cholesteryl ester (21%) mass, while the inhibitor significantly (p < 0.05) increased total (29%) and free cholesterol (29%) mass, compared with the relevant controls. Let-7d-5p inhibition significantly (p < 0.05) increased endogenous biosynthesis of cholesterol (38%) and cholesteryl ester (39%) pools in macrophage 'foam' cells, without altering the cholesterol efflux pathway, or esterification of exogenous radiolabelled oleate. Let-7d-5p inhibition in sterol-loaded cells increased the level of HMGA2 protein (32%; p < 0.05), while SiRNA knockdown of this protein (29%; p < 0.05) resulted in a (21%, p < 0.05) reduction in free cholesterol mass. Thus, induction of let-7d-5p, and repression of its target HMGA2, in macrophages is a protective response to the challenge of increased cholesterol influx into these cells; dysregulation of this response may contribute to atherosclerosis and other disorders such as cancer.
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Lightbody RJ, Taylor JMW, Dempsie Y, Graham A. MicroRNA sequences modulating inflammation and lipid accumulation in macrophage “foam” cells: Implications for atherosclerosis. World J Cardiol 2020; 12:303-333. [PMID: 32843934 PMCID: PMC7415235 DOI: 10.4330/wjc.v12.i7.303] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/03/2020] [Accepted: 06/10/2020] [Indexed: 02/06/2023] Open
Abstract
Accumulation of macrophage “foam” cells, laden with cholesterol and cholesteryl ester, within the intima of large arteries, is a hallmark of early “fatty streak” lesions which can progress to complex, multicellular atheromatous plaques, involving lipoproteins from the bloodstream and cells of the innate and adaptive immune response. Sterol accumulation triggers induction of genes encoding proteins mediating the atheroprotective cholesterol efflux pathway. Within the arterial intima, however, this mechanism is overwhelmed, leading to distinct changes in macrophage phenotype and inflammatory status. Over the last decade marked gains have been made in understanding of the epigenetic landscape which influence macrophage function, and in particular the importance of small non-coding micro-RNA (miRNA) sequences in this context. This review identifies some of the miRNA sequences which play a key role in regulating “foam” cell formation and atherogenesis, highlighting sequences involved in cholesterol accumulation, those influencing inflammation in sterol-loaded cells, and novel sequences and pathways which may offer new strategies to influence macrophage function within atherosclerotic lesions.
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Affiliation(s)
- Richard James Lightbody
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, United Kingdom
| | - Janice Marie Walsh Taylor
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, United Kingdom
| | - Yvonne Dempsie
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, United Kingdom
| | - Annette Graham
- Department of Biological and Biomedical Sciences, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, United Kingdom
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Zhao Z, He D, Ling F, Chu T, Huang D, Wu H, Ge J. CD4 + T cells and TGFβ1/MAPK signal pathway involved in the valvular hyperblastosis and fibrosis in patients with rheumatic heart disease. Exp Mol Pathol 2020; 114:104402. [PMID: 32061942 DOI: 10.1016/j.yexmp.2020.104402] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/07/2020] [Accepted: 02/12/2020] [Indexed: 12/20/2022]
Abstract
The aim of this study was to investigate the roles of CD4+ T cells and transforming growth factor beta (TGFβ1) in the pathological process of valvular hyperblastosis and fibrosis of patients with rheumatic heart disease (RHD). A total of 151 patients were enrolled, among whom, 78 patients were with RHD, and 73 were age and gender matched RHD negative patients. Blood samples and valve specimens were collected for analysis. Pathological changes and collagen fibers contents of valves were analyzed using HE and Masson staining. Percentage of peripheral blood CD4+ T cells was tested through flow cytometry. TGFβ1 level in serum were identified by ELISA. CD4+ T cells infiltration and expression of TGFβ1, p-p38, p-JNK, p-ERK in valves were detected by immunohistochemistry. The mRNA and protein levels of p38, JNK, ERK, TGFβ1, I-collagen and α-SMA were detected by qRT-PCR and western blotting, respectively. The heart valve tissues of RHD patients showed higher degrees of fibrosis, calcification and lymphocytes infiltration, which were mainly CD4+ T cells. In addition, compared with control group, RHD patients had more total CD4+ T cells in peripheral blood and valve tissues. Expression of TGFβ1, phosphorylation of JNK and p38, and synthesis of I-collagen in valve tissues of RHD patients were also significantly increased. Furthermore, we found a strong positive correlation between TGFβ1 expression and phosphorylation of JNK and p38. CD4+ T cells, and fibrogenic cytokine TGFβ1, which activate the intracellular MAPK signaling pathway may participate in the fibrosis of heart valve in RHD patients.
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Affiliation(s)
- Zhiwei Zhao
- Department of Cardiovascular Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China (USTC), Hefei, Anhui 230001, China.
| | - Danqing He
- Department of Ultrasound, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230022, China
| | - Fei Ling
- Department of Cardiovascular Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China (USTC), Hefei, Anhui 230001, China
| | - Tianshu Chu
- Department of Cardiovascular Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China (USTC), Hefei, Anhui 230001, China
| | - Dake Huang
- Comperhensive Laboratory of Anhui Medical University, Hefei, Anhui 230032, China
| | - Huaxun Wu
- Institute of Clinical Pharmacology, Anhui Medical University, Hefei, Anhui 230032, China
| | - Jianjun Ge
- Department of Cardiovascular Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China (USTC), Hefei, Anhui 230001, China.
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Yu H, Ma S, Sun L, Gao J, Zhao C. TGF‑β1 upregulates the expression of lncRNA‑ATB to promote atherosclerosis. Mol Med Rep 2019; 19:4222-4228. [PMID: 30942415 PMCID: PMC6471400 DOI: 10.3892/mmr.2019.10109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 10/17/2018] [Indexed: 02/01/2023] Open
Abstract
Transforming growth factor (TGF)-β1 is reported to be associated with the occurrence of atherosclerosis, although the mechanism remains unclear. Therefore, the present study aimed to investigate the involvement of TGF-β1 signaling in atherosclerosis. A total of 56 patients with atherosclerosis and 44 healthy volunteers were involved in this study. Serum expression of TGF-β1 and long non-coding RNA-ATB was detected by ELISA and quantitative polymerase chain reaction (qPCR). Receiver operating characteristic curve analysis was performed to analyze the diagnostic value of serum TGF-β1 and lncRNA-ATB for atherosclerosis. A human umbilical vein endothelial cell (HUVEC) line overexpressing lncRNA-ATB was constructed. The effects of TGF-β1 treatment and lncRNA-ATB overexpression on HUVEC cell proliferation and viability was detected with Cell Counting Kit-8 and MTT assays, respectively. Expression of TGF-β1 and pro-apoptotic Caspase-3 in lncRNA-ATB-overexpressing HUVECs was detected by western blotting. In addition, the expression of lncRNA-ATB in TGF-β1-treated HUVECs was detected by qPCR. It was demonstrated that serum TGF-β1 and lncRNA-ATB expression was significantly higher in atherosclerosis patients, compared with controls, and could be used to effectively distinguish patients from healthy individuals. TGF-β1 treatment and lncRNA-ATB overexpression reduced HUVEC viability and proliferation. TGF-β1 treatment increased the expression of lncRNA-ATB in HUVECs, while lncRNA-ATB overexpression had no significant effect on TGF-β1 expression. LncRNA-ATB silencing with small interfering RNA significantly reduced the effects of TGF-β1 treatment on the proliferation and viability of HUVECs. Furthermore, LncRNA-ATB overexpression upregulated the expression of caspase-3 in HUVECs. Therefore, it was concluded that TGF-β1 may have upregulated the expression of lncRNA-ATB to promote atherosclerosis, and lncRNA-ATB may serve as a potential therapeutic target for atherosclerosis. However, the mechanism remains to be further investigated.
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Affiliation(s)
- Huapeng Yu
- Department of Cardiovascular Medicine, The Fourth People's Hospital of Jinan, Jinan Research Institute of Cardiovascular Diseases, Jinan, Shandong 250031, P.R. China
| | - Shengting Ma
- Department of Cardiovascular Medicine, The Fourth People's Hospital of Jinan, Jinan Research Institute of Cardiovascular Diseases, Jinan, Shandong 250031, P.R. China
| | - Ling Sun
- Department of Cardiovascular Medicine, The Fourth People's Hospital of Jinan, Jinan Research Institute of Cardiovascular Diseases, Jinan, Shandong 250031, P.R. China
| | - Jing Gao
- Department of Cardiovascular Medicine, The Fourth People's Hospital of Jinan, Jinan Research Institute of Cardiovascular Diseases, Jinan, Shandong 250031, P.R. China
| | - Chengjun Zhao
- Department of Cardiovascular Medicine, The Fourth People's Hospital of Jinan, Jinan Research Institute of Cardiovascular Diseases, Jinan, Shandong 250031, P.R. China
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Testa G, Rossin D, Poli G, Biasi F, Leonarduzzi G. Implication of oxysterols in chronic inflammatory human diseases. Biochimie 2018; 153:220-231. [DOI: 10.1016/j.biochi.2018.06.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 06/07/2018] [Indexed: 12/18/2022]
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Mechanism of cyclosporine A nephrotoxicity: Oxidative stress, autophagy, and signalings. Food Chem Toxicol 2018; 118:889-907. [DOI: 10.1016/j.fct.2018.06.054] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/21/2018] [Accepted: 06/22/2018] [Indexed: 12/16/2022]
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Hypercholesterolemia Is Associated with the Subjective Evaluation of Postoperative Outcomes in Patients with Idiopathic Carpal Tunnel Syndrome Who Undergo Surgery: A Multivariate Analysis. Plast Reconstr Surg 2018; 141:941-948. [PMID: 29465486 DOI: 10.1097/prs.0000000000004228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Carpal tunnel syndrome is a compression neuropathy of the median nerve at the wrist; its symptoms include neuropathic pain and sensory and motor disturbance distributed by the median nerve. Carpal tunnel syndrome and hypercholesterolemia have similar backgrounds, but the effect of these similarities on postoperative outcomes has not been reported. Using multivariate analysis, the authors analyzed the relationship between prognostic factors, including the presence of hypercholesterolemia, and subjective postoperative outcomes of patients with idiopathic carpal tunnel syndrome. METHODS Of 168 hands with carpal tunnel syndrome that were treated surgically, 141 that were followed up and assessed 1 year postoperatively or thereafter were included. The mean postoperative follow-up period was 40.8 months. Surgery was performed through a small palmar skin incision under local anesthesia. The outcomes were postoperative symptoms, including pain and numbness, and overall Kelly assessment. RESULTS Preoperative numbness and pain resolved and alleviated in 94 of 141 hands and was diminished in 59 of 64 hands. Univariate analysis showed that postoperative numbness and Kelly assessment were significantly associated with hypercholesterolemia. Multivariate analysis showed that postoperative numbness was significantly associated with smoking and hypercholesterolemia, and Kelly assessment was significantly associated with smoking (adjusted OR, 3.3; 95 percent CI, 1.1 to 10; p = 0.04) and hypercholesterolemia (adjusted OR, 2.9; 95 percent CI, 1.4 to 6.3; p = 0.01). CONCLUSION Hypercholesterolemia, usually a systemic condition in sites other than the hand, is associated with the subjective evaluation of postoperative symptoms in patients with idiopathic carpal tunnel syndrome. CLINICAL QUESTION/LEVEL OF EVIDENCE Risk, III.
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Rutkowska A, Shimshek DR, Sailer AW, Dev KK. EBI2 regulates pro-inflammatory signalling and cytokine release in astrocytes. Neuropharmacology 2018; 133:121-128. [PMID: 29374507 DOI: 10.1016/j.neuropharm.2018.01.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/28/2017] [Accepted: 01/22/2018] [Indexed: 12/16/2022]
Abstract
The endogenous oxysterol 7α, 25-dihydroxycholesterol (7α25HC) ligand activates the G protein-coupled receptor EBI2 to regulate T cell-dependant antibody response and B cell migration. We have demonstrated that EBI2 is expressed in human and mouse astrocytes, that 7α25HC induces intracellular signalling and astrocyte migration, and that EBI2 plays a role in the crosstalk between astrocytes and macrophages. Recently, we demonstrate that EBI2 regulates myelin development and inhibits LPC-induced demyelination. Here, we show that 7α25HC inhibits LPS- and IL17/TNF-induced pro-inflammatory cytokine release in astrocytes. We observe the following: 1. Human astrocytes treated with IL17/TNF increases the nuclear translocation of NFκB, which is attenuated by pre-treatment with 7α25HC; 2. IL17/TNF increases cell impedance in human astrocytes, which is also attenuated by pre-treatment with 7α25HC; 3. The EBI2 antagonist NIBR189 inhibits these effects of 7α25HC, supporting the role of EBI2; 4. in vivo data corroborate these in vitro findings, showing that EBI2 knock-out (KO) animals display enhanced pro-inflammatory cytokine in response to LPS challenge, in the brain. These results demonstrate a role for oxysterol/EBI2 signalling in attenuating the response of astrocytes to pro-inflammatory signals as well as limiting the levels of pro-inflammatory cytokines in the brain.
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Affiliation(s)
- Aleksandra Rutkowska
- Drug Development, School of Medicine, Trinity College, Dublin, Ireland; Department of Laboratory Medicine, Medical University of Gdańsk, Poland.
| | - Derya R Shimshek
- Neuroscience, Novartis Institutes for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Andreas W Sailer
- Chemical Biology & Therapeutics, Novartis Institutes for BioMedical Research, Novartis Pharma AG, Basel, Switzerland
| | - Kumlesh K Dev
- Drug Development, School of Medicine, Trinity College, Dublin, Ireland
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Serra G, Deiana M, Spencer JPE, Corona G. Olive Oil Phenolics Prevent Oxysterol-Induced Proinflammatory Cytokine Secretion and Reactive Oxygen Species Production in Human Peripheral Blood Mononuclear Cells, Through Modulation of p38 and JNK Pathways. Mol Nutr Food Res 2017; 61. [PMID: 28815947 PMCID: PMC5765427 DOI: 10.1002/mnfr.201700283] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/25/2017] [Indexed: 01/28/2023]
Abstract
Scope The aim of the present study was to investigate the ability of extra virgin olive oil (EVOO) polyphenols to counteract the proinflammatory effects induced by dietary and endogenous oxysterols in ex vivo immune cells. Methods and results Peripheral blood mononuclear cells (PBMCs), separated from the whole blood of healthy donors, were utilized and were stimulated with an oxysterols mixture, in the presence of physiologically relevant concentrations of the EVOO polyphenols, hydroxytyrosol, tyrosol, and homovanillic alcohol. Oxysterols significantly increased the production of proinflammatory cytokines, interleukin‐1β, regulated on activation, normal T‐cell expressed and secreted and macrophage migration inhibitory factor in ex vivo cultured PBMCs. Increased levels of reactive oxygen species (ROS) were also detected along with increased phosphorylation of the p38 and JNK. All phenolic compounds significantly reduced cytokine secretion induced by the oxysterols and inhibited ROS production and mitogen activated protein kinase phosphorylation. Conclusions These results suggest that extra virgin olive oil polyphenols modulate the immune response induced by dietary and endogenous cholesterol oxidation products in human immune cells and may hold benefit in controlling chronic immune and/or inflammatory processes.
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Affiliation(s)
- Gessica Serra
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Monica Deiana
- Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy
| | - Jeremy P E Spencer
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Giulia Corona
- Health Sciences Research Centre, University of Roehampton, London, UK
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Gargiulo S, Testa G, Gamba P, Staurenghi E, Poli G, Leonarduzzi G. Oxysterols and 4-hydroxy-2-nonenal contribute to atherosclerotic plaque destabilization. Free Radic Biol Med 2017; 111:140-150. [PMID: 28057601 DOI: 10.1016/j.freeradbiomed.2016.12.037] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 12/22/2016] [Accepted: 12/24/2016] [Indexed: 12/31/2022]
Abstract
A growing bulk of evidence suggests that cholesterol oxidation products, known as oxysterols, and 4-hydroxy-2-nonenal (HNE), the major proatherogenic components of oxidized low density lipoproteins (oxLDLs), significantly contribute to atherosclerotic plaque progression and destabilization, with eventual plaque rupture. These oxidized lipids are involved in various key steps of this complex process, mainly thanks to their ability to induce inflammation, oxidative stress, and apoptosis. This review summarizes the current knowledge of the effects induced by these compounds on vascular cells, after their accumulation in the arterial wall and in the atherosclerotic plaque.
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Affiliation(s)
- Simona Gargiulo
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Gabriella Testa
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Paola Gamba
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Erica Staurenghi
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Giuseppe Poli
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy.
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O'sullivan AJ, O'callaghan YC, O'brien NM. Differential Effects of Mixtures of Cholesterol Oxidation Products on Bovine Aortic Endothelial Cells and Human Monocytic U937 Cells. Int J Toxicol 2016; 24:173-9. [PMID: 16040570 DOI: 10.1080/10915810590952951] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cholesterol oxidation products or oxysterols are of interest due to their hypothesized role in the development of atherosclerosis. The objective of the present study was to assess the cytotoxic effects of mixtures of oxysterols: 25-hydroxycholesterol (25-OHC), 7 β-hydroxycholesterol (7 β-OHC), and cholesterol-5 β,6 β-epoxide ( β-epox) on two cell types associated with the atherosclerotic process, bovine aortic endothelial (BAE) cells and human monocytic U937 cells. Cells were exposed to 25-OHC, 7 β-OHC, or β-epox, or equimolar mixtures (30 μM) of 25-OHC and 7 β-OHC, 25-OHC and β-epox, or 7 β-OHC and β-epox for 48 h. Cell viability was assessed using the fluorescein diacetate/ethidium bromide (FDA/ EtBr) assay and nuclear morphology following staining with Hoechst 33342. 25-OHC was the least toxic of the oxysterols and did not induce apoptosis in either cell line. Both 7 β-OHC and β-epox treatments were cytotoxic and induced apoptosis in the cells. Cotreatment with 25-OHC did not alter the toxicity of 7 β-OHC and β-epox in U937 cells but did decrease the percentage apoptotic cell death. In contrast, in the BAE cells cotreatment with 25-OHC had a slight protective effect on 7 β-OHC and β-epox–induced toxicities and a marked decrease in apoptotic cell death. The 7 β-OHC and β-epox mixture induced a significant increase in apoptotic cell death in U937 cells but decreased this mode of cell death in the BAE cells. The effects of oxysterols on glutathione levels also differed between the cells with changes noted in U937 and not in BAE cells. Results demonstrate interactive effects when oxysterols are studied as mixtures rather than single compounds in vitro.
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Affiliation(s)
- Aaron J O'sullivan
- Department of Food and Nutritional Sciences, University College Cork, Ireland
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Chen CL, Wu DC, Liu MY, Lin MW, Huang HT, Huang YB, Chen LC, Chen YY, Chen JJ, Yang PH, Kao YC, Chen PY. Cholest-4-en-3-one attenuates TGF-β responsiveness by inducing TGF-β receptors degradation in Mv1Lu cells and colorectal adenocarcinoma cells. J Recept Signal Transduct Res 2016; 37:189-199. [DOI: 10.1080/10799893.2016.1203944] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Chun-Lin Chen
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung, Taiwan, ROC
- Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
| | - Deng-Chyang Wu
- Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
- Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, ROC
| | - Min-Yun Liu
- Taiwan Ocean Research Institute, National Applied Research Laboratories, Kaohsiung, Taiwan, ROC
| | - Ming-Wei Lin
- Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
- Department of Pharmacy, School of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
| | - Hung-Tu Huang
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
- Division of Pathology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, ROC
| | - Yaw-Bin Huang
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
- Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
- Taiwan Ocean Research Institute, National Applied Research Laboratories, Kaohsiung, Taiwan, ROC
- Faculty of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan, ROC
| | - Li-Chai Chen
- Department of Pharmacy, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan, ROC
- Department of Pharmacy and Graduate Institute of Pharmaceutical Technology, Tajen University, Taiwan, ROC
| | - Yu-Yu Chen
- Department of Pharmacy, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan, ROC
| | - Jih-Jung Chen
- Department of Pharmacy, Zuoying Branch of Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan, ROC
- Department of Pharmacy and Graduate Institute of Pharmaceutical Technology, Tajen University, Taiwan, ROC
- Department of Medical Research, China Medical University Hospital, Taichung 404, Taiwan
| | - Pei-Hua Yang
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
| | - Yu-Chen Kao
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
| | - Pei-Yu Chen
- Department of Biological Sciences, National Sun Yat-Sen University, Kaohsiung Taiwan, ROC
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Gargiulo S, Gamba P, Testa G, Leonarduzzi G, Poli G. The role of oxysterols in vascular ageing. J Physiol 2016; 594:2095-113. [PMID: 26648329 DOI: 10.1113/jp271168] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 11/06/2015] [Indexed: 12/24/2022] Open
Abstract
The ageing endothelium progressively loses its remarkable and crucial ability to maintain homeostasis of the vasculature, as it acquires a proinflammatory phenotype. Cellular and structural changes gradually accumulate in the blood vessels, and markedly in artery walls. Most changes in aged arteries are comparable to those occurring during the atherogenic process, the latter being more marked: pro-oxidant and proinflammatory molecules, mainly deriving from or triggered by oxidized low density lipoproteins (oxLDLs), are undoubtedly a major driving force of this process. Oxysterols, quantitatively relevant components of oxLDLs, are likely candidate molecules in the pathogenesis of vascular ageing, because of their marked pro-oxidant, proinflammatory and proapoptotic properties. An increasing bulk of experimental data point to the contribution of a variety of oxysterols of pathophysiological interest, also in the age-related genesis of endothelium dysfunction, intimal thickening due to lipid accumulation, and smooth muscle cell migration and arterial stiffness due to increasing collagen deposition and calcification. This review provides an updated analysis of the molecular mechanisms whereby oxysterols accumulating in the wall of ageing blood vessels may 'activate' endothelial and monocytic cells, through expression of an inflammatory phenotype, and 'convince' smooth muscle cells to proliferate, migrate and, above all, to act as fibroblast-like cells.
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Affiliation(s)
- Simona Gargiulo
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Paola Gamba
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Gabriella Testa
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
| | - Giuseppe Poli
- Department of Clinical and Biological Sciences, University of Torino, San Luigi Hospital, 10043 Orbassano, Torino, Italy
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Agarwal I, Arnold A, Glazer NL, Barasch E, Djousse L, Fitzpatrick AL, Gottdiener JS, Ix JH, Jensen RA, Kizer JR, Rimm EB, Siscovick DS, Tracy RP, Wong TY, Mukamal KJ. Fibrosis-related biomarkers and large and small vessel disease: the Cardiovascular Health Study. Atherosclerosis 2015; 239:539-46. [PMID: 25725316 PMCID: PMC4517825 DOI: 10.1016/j.atherosclerosis.2015.02.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Revised: 02/07/2015] [Accepted: 02/10/2015] [Indexed: 01/14/2023]
Abstract
OBJECTIVE Fibrosis has been implicated in a number of pathological, organ-based conditions of the liver, kidney, heart, and lungs. The objective of this study was to determine whether biomarkers of fibrosis are associated with vascular disease in the large and/or small vessels. METHODS We evaluated the associations of two circulating biomarkers of fibrosis, transforming growth factor-β (TGF-β) and procollagen type III N-terminal propeptide (PIIINP), with incident peripheral artery disease (PAD) and subclinical macrovascular (carotid intima-media thickness, flow-mediated vasodilation, ankle-brachial index, retinal vein diameter), and microvascular (retinal artery diameter and retinopathy) disease among older adults in the Cardiovascular Health Study. We measured TGF-β and PIIINP from samples collected in 1996 and ascertained clinical PAD through 2011. Measurements of large and small vessels were collected between 1996 and 1998. RESULTS After adjustment for sociodemographic, clinical, and biochemical risk factors, TGF-β was associated with incident PAD (hazard ratio [HR] = 1.36 per doubling of TGF-β, 95% confidence interval [CI] = 1.04, 1.78) and retinal venular diameter (1.63 μm per doubling of TGF-β, CI = 0.23, 3.02). PIIINP was not associated with incident PAD, but was associated with carotid intima-media thickness (0.102 mm per doubling of PIIINP, CI = 0.029, 0.174) and impaired brachial artery reactivity (-0.20% change per doubling of PIIINP, CI = -0.39, -0.02). Neither TGF-β nor PIIINP were associated with retinal arteriolar diameter or retinopathy. CONCLUSIONS Serum concentrations of fibrosis-related biomarkers were associated with several measures of large vessel disease, including incident PAD, but not with small vessel disease. Fibrosis may contribute to large vessel atherosclerosis in older adults.
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Affiliation(s)
- Isha Agarwal
- Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA.
| | - Alice Arnold
- Department of Biostatistics, University of Washington, Seattle, WA, USA
| | | | - Eddy Barasch
- Department of Research and Education, St. Francis Hospital/SUNY at Stony Brook, Stony Brook, NY, USA
| | - Luc Djousse
- Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA; Boston Veterans Healthcare System, Boston, MA, USA
| | | | - John S Gottdiener
- Department of Medicine, University of Maryland Medical School, Baltimore, MD, USA
| | - Joachim H Ix
- Department of Medicine, University of California San Diego and Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Richard A Jensen
- Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Jorge R Kizer
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Eric B Rimm
- Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA; Department of Nutrition, Harvard School of Public Health, Boston, MA, USA; Channing Division of Network Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - David S Siscovick
- Department of Epidemiology, University of Washington, Seattle, WA, USA; Cardiovascular Health Research Unit, Department of Medicine, University of Washington, Seattle, WA, USA
| | - Russell P Tracy
- Department of Biochemistry, University of Vermont, Burlington, VT, USA
| | - Tien Y Wong
- Department of Ophthalmology, Singapore Eye Research Institute, National University of Singapore, Singapore
| | - Kenneth J Mukamal
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
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15
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Spickett C, Fedorova M, Hoffmann R, Forman H. An Introduction to Redox Balance and Lipid Oxidation. OXIDATIVE STRESS AND DISEASE 2015. [DOI: 10.1201/b18138-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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16
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Alemany L, Barbera R, Alegría A, Laparra JM. Plant sterols from foods in inflammation and risk of cardiovascular disease: a real threat? Food Chem Toxicol 2014; 69:140-9. [PMID: 24747512 DOI: 10.1016/j.fct.2014.03.038] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 03/25/2014] [Accepted: 03/28/2014] [Indexed: 12/11/2022]
Abstract
High dietary intakes of cholesterol together with sedentary habits have been identified as major contributors to atherosclerosis. The latter has long been considered a cholesterol storage disease; however, today atherosclerosis is considered a more complex disease in which both innate and adaptive immune-inflammatory mechanisms as well as bacteria play a major role, in addition to interactions between the arterial wall and blood components. This scenario has promoted nutritional recommendations to enrich different type of foods with plant sterols (PS) because of their cholesterol-lowering effects. In addition to cholesterol, PS can also be oxidized during food processing or storage, and the oxidized derivatives, known as phytosterol oxidation products (POPs), can make an important contribution to the negative effects of both cholesterol and cholesterol oxidation oxides (COPs) in relation to inflammatory disease onset and the development of atherosclerosis. Most current research efforts have focused on COPs, and evaluations of the particular role and physiopathological implications of specific POPs have been only inferential. Appreciation of the inflammatory role described for both COPs and POPs derived from foods also provides additional reasons for safety studies after long-term consumption of PS. The balance and relevance for health of all these effects deserves further studies in humans. This review summarizes current knowledge about the presence of sterol oxidation products (SOPs) in foods and their potential role in inflammatory process and cardiovascular disease.
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Affiliation(s)
- L Alemany
- Nutrition and Food Chemistry, Faculty of Pharmacy, University of Valencia, Avda. Vicente Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - R Barbera
- Nutrition and Food Chemistry, Faculty of Pharmacy, University of Valencia, Avda. Vicente Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - A Alegría
- Nutrition and Food Chemistry, Faculty of Pharmacy, University of Valencia, Avda. Vicente Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
| | - J M Laparra
- Microbial Ecology and Nutrition Research Group, Institute of Agrochemistry and Food Technology, National Research Council (IATA-CSIC), Avda. Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
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17
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Using a large-scale knowledge database on reactions and regulations to propose key upstream regulators of various sets of molecules participating in cell metabolism. BMC SYSTEMS BIOLOGY 2014; 8:32. [PMID: 24635915 PMCID: PMC4004165 DOI: 10.1186/1752-0509-8-32] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 03/03/2014] [Indexed: 12/21/2022]
Abstract
Background Most of the existing methods to analyze high-throughput data are based on gene ontology principles, providing information on the main functions and biological processes. However, these methods do not indicate the regulations behind the biological pathways. A critical point in this context is the extraction of information from many possible relationships between the regulated genes, and its combination with biochemical regulations. This study aimed at developing an automatic method to propose a reasonable number of upstream regulatory candidates from lists of various regulated molecules by confronting experimental data with encyclopedic information. Results A new formalism of regulated reactions combining biochemical transformations and regulatory effects was proposed to unify the different mechanisms contained in knowledge libraries. Based on a related causality graph, an algorithm was developed to propose a reasonable set of upstream regulators from lists of target molecules. Scores were added to candidates according to their ability to explain the greatest number of targets or only few specific ones. By testing 250 lists of target genes as inputs, each with a known solution, the success of the method to provide the expected transcription factor among 50 or 100 proposed regulatory candidates, was evaluated to 62.6% and 72.5% of the situations, respectively. An additional prioritization among candidates might be further realized by adding functional ontology information. The benefit of this strategy was proved by identifying PPAR isotypes and their partners as the upstream regulators of a list of experimentally-identified targets of PPARA, a pivotal transcriptional factor in lipid oxidation. The proposed candidates participated in various biological functions that further enriched the original information. The efficiency of the method in merging reactions and regulations was also illustrated by identifying gene candidates participating in glucose homeostasis from an input list of metabolites involved in cell glycolysis. Conclusion This method proposes a reasonable number of regulatory candidates for lists of input molecules that may include transcripts of genes and metabolites. The proposed upstream regulators are the transcription factors themselves and protein complexes, so that a multi-level description of how cell metabolism is regulated is obtained.
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18
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Alemany L, Laparra JM, Barberá R, Alegría A. Relative expression of cholesterol transport-related proteins and inflammation markers through the induction of 7-ketosterol-mediated stress in Caco-2 cells. Food Chem Toxicol 2013; 56:247-53. [PMID: 23454145 DOI: 10.1016/j.fct.2013.02.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 02/14/2013] [Accepted: 02/20/2013] [Indexed: 01/30/2023]
Abstract
Human diets contain sterol oxidation products that can induce cytotoxic effects, mainly caused by cholesterol oxides. However, phytosterol oxides effects have been less extensively investigated. This study evaluates the production of inflammatory biomarkers (IL-1β, IL-8, IL-10, TNFα) and the influence of gene expression transporters and enzymes related to cholesterol absorption and metabolism (NPC1L1, ABCG5/8, HMGCoA, ACAT) produced by 7-ketosterols (stigmasterol/cholesterol) in Caco-2 cells. These effects were linked to intracellular signaling pathways by using several inhibitors. Results showed 7-ketostigmasterol to have a greater proinflammatory potential than 7-ketocholesterol. In non-pre-treated cells, only efflux transporters were down-regulated by 7-ketosterols, showing a greater influence upon ABCG5 expression. Cell-pre-incubation with bradykinin induced changes in ABCG expression levels after 7-ketostigmasterol-incubation; however, the energetic metabolism inhibition reduced NPC1L1 expression only in 7-ketocholesterol-incubated cells. In non-pre-treated cells, HMG-CoA was up-regulated by both 7-ketosterols. However, exposure to inhibitors down-regulated the expression levels, mainly in 7-ketocholesterol-incubated cells. While ACAT expression values in non-pre-treated cells were unchanged, exposure to inhibitors caused down-regulation of mRNA levels. These results suggest that internalization and excretion of 7-ketostigmasterol is probably influenced by [Ca]i, which also could mediate HMGCoA activity in POPs metabolism. However, energetic metabolism and reducing equivalents exert different influences upon the 7-ketosterol internalization.
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Affiliation(s)
- L Alemany
- Nutrition and Food Chemistry, Faculty of Pharmacy, University of Valencia, Avda. Vicente Andrés Estellés s/n, 46100 Burjassot, Valencia, Spain
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19
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Vaya J. The association between biomarkers in the blood and carotid plaque composition-focusing on oxidized lipids, oxysterols and plaque status. Biochem Pharmacol 2013; 86:15-8. [PMID: 23395697 DOI: 10.1016/j.bcp.2013.01.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 01/24/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
Abstract
Human atherosclerotic plaque is composed of a large mixture of elements, predominantly lipids and oxidized lipids, lipid-loaded macrophages and smooth muscle cells, forming foam cells. Plaque contents undergo dynamic changes during the plaque's progression, being in a constant interaction with the circulating blood. During the mutual interaction between blood and plaque and the specific biochemical processes occurring in both, specific molecules can be generated in the serum which might provide information on plaque status. This information, mostly on plaque vulnerability, is highly important for making appropriate treatment decisions before neurological symptoms appear. The present review summarizes plaque contents, mostly lipids, oxidized lipids, oxidized products of cholesterol (oxysterols), and covers the recent literature on their association with biomarkers in the blood and on the possibility of using them for providing information on plaque status.
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Affiliation(s)
- Jacob Vaya
- Department of Oxidative Stress and Human Diseases, MIGAL - Galilee Research Institute, Kiryat Shmona 11016, Israel; Tel Hai College, Israel.
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20
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Gargiulo S, Gamba P, Testa G, Sottero B, Maina M, Guina T, Biasi F, Poli G, Leonarduzzi G. Molecular signaling involved in oxysterol-induced β₁-integrin over-expression in human macrophages. Int J Mol Sci 2012. [PMID: 23203064 PMCID: PMC3509580 DOI: 10.3390/ijms131114278] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The hypercholesterolemia-atherosclerosis association is now established; hypercholesterolemia may induce vascular-cell activation, subsequently increasing expression of adhesion molecules, cytokines, chemokines, growth factors, and other key inflammatory molecules. Among inflammatory molecules expressed by vascular cells, integrins play a critical role in regulating macrophage activation and migration to the site of inflammation, by mediating cell-cell and cell-extracellular matrix interactions. The main lipid oxidation products present in oxidized LDL that may be responsible for inflammatory processes in atherogenesis, are cholesterol oxidation products, known as oxysterols. This study demonstrates the effect of an oxysterol mixture, compatible with that detectable in human hypercholesterolemic plasma, on the expression and synthesis of β1-integrin in cells of the macrophage lineage. The molecular signaling whereby oxysterols induce β1-integrin up-regulation is also comprehensively investigated. Over-expression of β1-integrin depends on activation of classic and novel members of protein kinase C and extracellular signal-regulated kinases 1 and 2, as well as of the up-stream G-protein (Gq and G13), c-Src, and phospholipase C. In addition, the localization of β1-integrin in advanced human carotid plaques is highlighted, marking its importance in atherosclerotic plaque progression.
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Affiliation(s)
- Simona Gargiulo
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Hospital, Regione Gonzole 10, Orbassano 10043, Turin, Italy.
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21
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Evidence of cell damage induced by major components of a diet-compatible mixture of oxysterols in human colon cancer CaCo-2 cell line. Biochimie 2012; 95:632-40. [PMID: 23092829 DOI: 10.1016/j.biochi.2012.10.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Accepted: 10/15/2012] [Indexed: 01/29/2023]
Abstract
Cholesterol oxidation products, termed oxysterols, have been shown to be more reactive than unoxidized cholesterol, possessing marked pro-inflammatory and cytotoxic effects in a number of cells and tissues. Oxysterols, absorbed with the diet as products of cholesterol auto-oxidation, have recently been suggested to potentially interfere with homeostasis of the mucosal intestinal epithelium, by promoting and sustaining irreversible damage. However, the treatment of colon cancer cells with a diet-compatible mixture of oxysterols does not elicit the same responses than individual components added to the cells at the same concentrations at which they are present in the mixture. Sixty μM oxysterol mixture showed a slight pro-apoptotic effect on human colon cancer CaCo-2 cell line, evaluated in terms of caspase-3 and caspase-7 activation; conversely, 7α-hydroxycholesterol, 7β-hydroxycholesterol and 5α,6α-epoxycholesterol were identified to be able to induce a significant pro-apoptotic effect if added to cell culture singly; 7β-hydroxycholesterol had stronger action than other compounds. The enhanced production of reactive oxygen species through up-regulation of the colonic NADPH-oxidase isoform NOX1 appeared to be the key event in oxysterol-induced apoptosis in these colon cancer cells. As regards pro-inflammatory effects of oxysterols, IL-8 and MCP-1 were evaluated for their chemotactic activity. Only MCP-1 production was significantly induced by 7β-hydroxycholesterol, as well as by cholesterol and oxysterol mixture. However, oxysterol-induced inflammation appeared to be NOX1-independent, suggesting a secondary role of this enzyme in inducing inflammation in colon cancer cells. A selective cell death induced by specific oxysterols against colon cancer cells, mainly exploiting their ability to activate NOX1 in generating oxidative reactions, might represent a promising field of investigation in colorectal cancer, and might bring new insights on strategies in anticancer therapy.
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22
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Leonarduzzi G, Gamba P, Gargiulo S, Biasi F, Poli G. Inflammation-related gene expression by lipid oxidation-derived products in the progression of atherosclerosis. Free Radic Biol Med 2012; 52:19-34. [PMID: 22037514 DOI: 10.1016/j.freeradbiomed.2011.09.031] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/16/2011] [Accepted: 09/24/2011] [Indexed: 12/31/2022]
Abstract
Vascular areas of atherosclerotic development persist in a state of inflammation, and any further inflammatory stimulus in the subintimal area elicits a proatherogenic response; this alters the behavior of the artery wall cells and recruits further inflammatory cells. In association with the inflammatory response, oxidative events are also involved in the development of atherosclerotic plaques. It is now unanimously recognized that lipid oxidation-derived products are key players in the initiation and progression of atherosclerotic lesions. Oxidized lipids, derived from oxidatively modified low-density lipoproteins (LDLs), which accumulate in the intima, strongly modulate inflammation-related gene expression, through involvement of various signaling pathways. In addition, considerable evidence supports a proatherogenic role of a large group of potent bioactive lipids called eicosanoids, which derive from oxidation of arachidonic acid, a component of membrane phospholipids. Of note, LDL lipid oxidation products might regulate eicosanoid production, modulating the enzymatic degradation of arachidonic acid by cyclooxygenases and lipoxygenases; these enzymes might also directly contribute to LDL oxidation. This review provides a comprehensive overview of current knowledge on signal transduction pathways and inflammatory gene expression, modulated by lipid oxidation-derived products, in the progression of atherosclerosis.
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23
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Pardali E, Ten Dijke P. TGFβ signaling and cardiovascular diseases. Int J Biol Sci 2012; 8:195-213. [PMID: 22253564 PMCID: PMC3258560 DOI: 10.7150/ijbs.3805] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Accepted: 12/01/2011] [Indexed: 12/19/2022] Open
Abstract
Transforming growth factor β (TGFβ) family members are involved in a wide range of diverse functions and play key roles in embryogenesis, development and tissue homeostasis. Perturbation of TGFβ signaling may lead to vascular and other diseases. In vitro studies have provided evidence that TGFβ family members have a wide range of diverse effects on vascular cells, which are highly dependent on cellular context. Consistent with these observations genetic studies in mice and humans showed that TGFβ family members have ambiguous effects on the function of the cardiovascular system. In this review we discuss the recent advances on TGFβ signaling in (cardio)vascular diseases, and describe the value of TGFβ signaling as both a disease marker and therapeutic target for (cardio)vascular diseases.
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Affiliation(s)
- Evangelia Pardali
- Department of Cardiology and Angiology, University Hospital Münster, Münster, Germany.
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24
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Anti-atherogenic and anti-angiogenic activities of polyphenols from propolis. J Nutr Biochem 2011; 23:557-66. [PMID: 21764281 DOI: 10.1016/j.jnutbio.2011.02.012] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 01/10/2011] [Accepted: 02/22/2011] [Indexed: 11/21/2022]
Abstract
Propolis is a polyphenol-rich resinous substance extensively used to improve health and prevent diseases. The effects of polyphenols from different sources of propolis on atherosclerotic lesions and inflammatory and angiogenic factors were investigated in LDL receptor gene (LDLr-/-) knockout mice. The animals received a cholesterol-enriched diet to induce the initial atherosclerotic lesions (IALs) or advanced atherosclerotic lesions (AALs). The IAL or AAL animals were divided into three groups, each receiving polyphenols from either the green, red or brown propolis (250 mg/kg per day) by gavage. After 4 weeks of polyphenol treatment, the animals were sacrificed and their blood was collected for lipid profile analysis. The atheromatous lesions at the aortic root were also analyzed for gene expression of inflammatory and angiogenic factors by quantitative real-time polymerase chain reaction and immunohistochemistry. All three polyphenol extracts improved the lipid profile and decreased the atherosclerotic lesion area in IAL animals. However, only polyphenols from the red propolis induced favorable changes in the lipid profiles and reduced the lesion areas in AAL mice. In IAL groups, VCAM, MCP-1, FGF, PDGF, VEGF, PECAM and MMP-9 gene expression was down-regulated, while the metalloproteinase inhibitor TIMP-1 gene was up-regulated by all polyphenol extracts. In contrast, for advanced lesions, only the polyphenols from red propolis induced the down-regulation of CD36 and the up-regulation of HO-1 and TIMP-1 when compared to polyphenols from the other two types of propolis. In conclusion, polyphenols from propolis, particularly red propolis, are able to reduce atherosclerotic lesions through mechanisms including the modulation of inflammatory and angiogenic factors.
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25
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Red wine prevents the postprandial increase in plasma cholesterol oxidation products: a pilot study. Br J Nutr 2011; 105:1718-23. [DOI: 10.1017/s0007114510005544] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Moderate wine consumption has been shown to lower cardiovascular risk. One of the mechanisms could involve the control of postprandial hyperlipaemia, a well-defined risk factor for atherosclerosis, reasonably by reducing the absorption of lipid oxidised species from the meal. The objective of the present study was to investigate whether wine consumption with the meal is able to reduce the postprandial increase in plasma lipid hydroperoxides and cholesterol oxidation products, in human subjects. In two different study sessions, twelve healthy volunteers consumed the same test meal rich in oxidised and oxidisable lipids (a double cheeseburger), with 300 ml of water (control) or with 300 ml of red wine (wine). The postprandial plasma concentration of cholesterol oxidation products was measured by GC–MS. The control meal induced a significant increase in the plasma concentration of lipid hydroperoxides and of two cholesterol oxidation products, 7-β-hydroxycholesterol and 7-ketocholesterol. The postprandial increase in lipid hydroperoxides and cholesterol oxidation products was fully prevented by wine when consumed with the meal. In conclusion, the present study provides evidence that consumption of wine with the meal could prevent the postprandial increase in plasma cholesterol oxidation products.
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26
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Negre-Salvayre A, Auge N, Ayala V, Basaga H, Boada J, Brenke R, Chapple S, Cohen G, Feher J, Grune T, Lengyel G, Mann GE, Pamplona R, Poli G, Portero-Otin M, Riahi Y, Salvayre R, Sasson S, Serrano J, Shamni O, Siems W, Siow RCM, Wiswedel I, Zarkovic K, Zarkovic N. Pathological aspects of lipid peroxidation. Free Radic Res 2010; 44:1125-71. [PMID: 20836660 DOI: 10.3109/10715762.2010.498478] [Citation(s) in RCA: 474] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Lipid peroxidation (LPO) product accumulation in human tissues is a major cause of tissular and cellular dysfunction that plays a major role in ageing and most age-related and oxidative stress-related diseases. The current evidence for the implication of LPO in pathological processes is discussed in this review. New data and literature review are provided evaluating the role of LPO in the pathophysiology of ageing and classically oxidative stress-linked diseases, such as neurodegenerative diseases, diabetes and atherosclerosis (the main cause of cardiovascular complications). Striking evidences implicating LPO in foetal vascular dysfunction occurring in pre-eclampsia, in renal and liver diseases, as well as their role as cause and consequence to cancer development are addressed.
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Otaegui-Arrazola A, Menéndez-Carreño M, Ansorena D, Astiasarán I. Oxysterols: A world to explore. Food Chem Toxicol 2010; 48:3289-303. [PMID: 20870006 DOI: 10.1016/j.fct.2010.09.023] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Revised: 09/15/2010] [Accepted: 09/16/2010] [Indexed: 11/25/2022]
Abstract
Oxysterols (oxidized derivatives of cholesterol and phytosterols) can be generated in the human organism through different oxidation processes, some requiring enzymes. Furthermore, oxysterols are also present in food due to lipid oxidation reactions caused by heating treatments, contact with oxygen, exposure to sunlight, etc., and they could be absorbed from the diet, at different rates depending on their side chain length. In the organism, oxysterols can follow different routes: secreted into the intestinal lumen, esterified and distributed by lipoproteins to different tissues or degraded, mainly in the liver. Cholesterol oxidation products (COPs) have shown cytotoxicity, apoptotic and pro-inflammatory effects and they have also been linked with chronic diseases including atherosclerotic and neurodegenerative processess. In the case of phytosterol oxidation products (POPs), more research is needed on toxic effects. Nevertheless, current knowledge suggests they may also cause cytotoxic and pro-apoptotic effects, although at higher concentrations than COPs. Recently, new beneficial biological activities of oxysterols are being investigated. Whereas COPs are associated with cholesterol homeostasis mediated by different mechanisms, the implication of POPs is not clear yet. Available literature on sources of oxysterols in the organism, metabolism, toxicity and potential beneficial effects of these compounds are reviewed in this paper.
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Affiliation(s)
- A Otaegui-Arrazola
- Department of Food Science and Nutrition, Physiology and Toxicology, Faculty of Pharmacy, University of Navarra, Pamplona, Spain
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28
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Kulach A, Dabek J, Wilczok T, Gasior Z. Changes in transforming growth factor β and its receptors' mRNA expression in monocytes from patients with acute coronary syndromes. Arch Med Sci 2010; 6:526-32. [PMID: 22371795 PMCID: PMC3284066 DOI: 10.5114/aoms.2010.14463] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 01/05/2010] [Accepted: 01/24/2010] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION Transforming growth factor β (TGF-β) is thought to be a vasoprotective cytokine. Numerous reports confirm its significance in blood and plaques. There is, however, a lack of information on the molecular mechanisms involving TGF-β in circulating inflammatory cells in atherogenesis. sThe aim of the study was to assess gene expression of TGF-β and its receptors in monocytes from patients with acute coronary syndromes (ACS) and the effect of standard treatment on the studied genes. MATERIAL AND METHODS The study was carried out in 32 patients with ACS and 15 healthy subjects. Gene expression of TGF-β and receptors TGF-βRI and TGF-βRII was evaluated on day 1 and 5 in the study group and once in controls. The number of mRNA copies isolated from monocytes was assessed by QRT-PCR. RESULTS Monocytes of ACS patients showed slightly elevated transcriptional activity of TGF-β1 and its receptors RI and RII genes (0.29 ±0.043 vs. 0.08 ±0.020, p = 0.05; 0.071 ±0.022 vs. 0.036 ±0.023, p < 0.05; 0.134 ±0.020 vs. 0.048 ±0.016, p < 0.05, respectively). After 5-day standard treatment modest reduction of TGF-βRI expression was observed. The studied genes' expression was unrelated to ejection fraction, myocardial necrosis markers, GRACE score, time from the onset of pain to percutaneous coronary intervention and angiographic findings. Among risk factors family history of CAD was associated with increased TGF-βRI expression. Moreover, the presence of 4 or more classic risk factors correlated with higher TGF-βRI expression. CONCLUSIONS Monocytes of ACS patients demonstrate overexpression of TGF-β1 and its receptors' genes. Five-day standard treatment downregulated the TGF-βRI gene but did not affect TGF-β1 and TGF-βRII.
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Affiliation(s)
- Andrzej Kulach
- Department of Cardiology, Medical University of Silesia, Katowice, Poland
| | - Jozefa Dabek
- Department of Cardiology, Medical University of Silesia, Katowice, Poland
| | - Tadeusz Wilczok
- Department of Molecular Biology and Medical Genetics, Medical University of Silesia, Sosnowiec, Poland
| | - Zbigniew Gasior
- Department of Cardiology, Medical University of Silesia, Katowice, Poland
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Leonarduzzi G, Gargiulo S, Gamba P, Perrelli MG, Castellano I, Sapino A, Sottero B, Poli G. Molecular signaling operated by a diet-compatible mixture of oxysterols in up-regulating CD36 receptor in CD68 positive cells. Mol Nutr Food Res 2010; 54 Suppl 1:S31-41. [DOI: 10.1002/mnfr.200900493] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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30
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Gargiulo S, Gamba P, Sottero B, Biasi F, Chiarpotto E, Serviddio G, Vendemiale G, Poli G, Leonarduzzi G. The core-aldehyde 9-oxononanoyl cholesterol increases the level of transforming growth factor beta1-specific receptors on promonocytic U937 cell membranes. Aging Cell 2009; 8:77-87. [PMID: 19302374 DOI: 10.1111/j.1474-9726.2009.00454.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Among the broad variety of compounds generated via oxidative reactions in low-density lipoproteins (LDL) and subsequently found in the atherosclerotic plaque are aldehydes that are still esterified to the parent lipid, termed core aldehydes. The most represented cholesterol core aldehyde in LDL is 9-oxononanoyl cholesterol (9-ONC), an oxidation product of cholesteryl linoleate. 9-ONC, at a concentration detectable in biological material, markedly up-regulates mRNA expression and protein level of both the pro-fibrogenic and pro-apoptotic cytokine transforming growth factor beta1 (TGF-beta1) and the TGF-beta receptor type I (TbetaRI) in human U937 promonocytic cells. We also observed increased membrane presentation of TGF-beta receptor type II (TbetaRII). Experiments employing the TbetaRI inhibitor SB431542, or the TGFbeta antagonist DANFc chimera, have shown that the effect on TbetaRI is directly induced by 9-ONC, while TbetaRII up-regulation seems stimulated by its specific ligand, i.e. TGFbeta1, over-secreted meanwhile by treated cells. Increased levels of the cytokine and of its specific receptors in 9-ONC-treated cells clearly occurs through stimulation of extracellular signal-regulated kinase 1 and 2 (ERK1/2), as demonstrated by ERK1/2 knockdown experiments using mitogen-activated protein kinase/extracellular signal-regulated kinase 1 and 2 (MEK1 and MEK2) siRNAs, or PD98059, a selective MEK1/2 inhibitor. 9-ONC might thus sustain further vascular remodeling due to atherosclerosis, not simply by stimulating synthesis of the pro-fibrogenic cytokine TGF-beta1 in vascular cells, but also and chiefly by enhancing the TGF-beta1 autocrine loop, because of the marked up-regulation of the cytokine's specific receptors TbetaRI and TbetaRII.
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Affiliation(s)
- Simona Gargiulo
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy
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31
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Schwartz YS, Dushkin MI, Komarova NI, Vorontsova EV, Kuznetsova IS. Cholesterol-induced stimulation of postinflammatory liver fibrosis. Bull Exp Biol Med 2009; 145:692-5. [PMID: 19110552 DOI: 10.1007/s10517-008-0175-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We studied the effect of high-cholesterol diet and factors inhibiting 3-hydroxy-3-methylglutaryl coenzyme A reductase on the development of liver fibrosis in C57Bl/6 mice with CCl4- or zymosan-induced hepatitis. Feeding a high-cholesterol diet led to a sharp increase in collagen content in the liver tissue of animals with CCl4-induced or zymosan-induced hepatitis. Atorvastatin and calcitriol produced less pronounced fibrogenic effects. Mevalonate partially prevented the development of cholesterol-induced fibrogenesis. High-cholesterol diet led to accumulation of oxysterols, cholesterol esters, and triglycerides and increased the expression of transforming growth factor-beta1 mRNA in liver tissue. Cholesterol-induced potentiation of the fibrogenic response is probably associated with transforming growth factor-beta1 induction due to accumulation of lipids and oxysterols in the liver.
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Affiliation(s)
- Y Sh Schwartz
- Institute of Therapy, Siberian Division of the Russian Academy of Medical Sciences, Novosibirsk. Russia.
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Tavori H, Aviram M, Khatib S, Musa R, Nitecki S, Hoffman A, Vaya J. Human carotid atherosclerotic plaque increases oxidative state of macrophages and low-density lipoproteins, whereas paraoxonase 1 (PON1) decreases such atherogenic effects. Free Radic Biol Med 2009; 46:607-15. [PMID: 19103284 DOI: 10.1016/j.freeradbiomed.2008.11.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 11/13/2008] [Accepted: 11/16/2008] [Indexed: 02/06/2023]
Abstract
Human atherosclerotic plaque contains a variety of oxidized lipids, which can facilitate further oxidation. Paraoxonase 1 (PON1) is a high-density lipoprotein (HDL)-associated esterase (lipolactonase), exhibiting antiatherogenic properties. The aims of the present study were to examine the oxidizing potency of the human carotid plaque lipid extract (LE), and the antiatherogenic role of PON1 on LE oxidation competence. Human carotid plaques were extracted by organic solvent, and the extract was incubated with lipoprotein particles, with macrophages, or with probes sensitive to oxidative stress, with or without preincubation with PON1, followed by oxidative-stress assessment. Our findings imply that the LE oxidized LDL, macrophages, and exogenous probes and decreases HDL-mediated cholesterol efflux from macrophages, in a dose-dependent manner. Incubation of PON1 with LE significantly affects LE composition, reduces LE atherogenic properties, and decreases the extract's total peroxide concentration by 44%, macrophage oxidation by 25%, and probe oxidation by up to 52%. We conclude that these results expand our understanding of how the plaque itself accelerates atherogenesis and provides an important mechanism for attenuation of atherosclerosis development by the antioxidant action of PON1 on the atherosclerotic plaque.
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Affiliation(s)
- Hagai Tavori
- MIGAL - Galilee Technology Center, Kiryat Shmona, Tel Hai College, Israel
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33
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Ferré N, Martínez-Clemente M, López-Parra M, González-Périz A, Horrillo R, Planagumà A, Camps J, Joven J, Tres A, Guardiola F, Bataller R, Arroyo V, Clària J. Increased susceptibility to exacerbated liver injury in hypercholesterolemic ApoE-deficient mice: potential involvement of oxysterols. Am J Physiol Gastrointest Liver Physiol 2009; 296:G553-62. [PMID: 19136384 DOI: 10.1152/ajpgi.00547.2007] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The contribution of metabolic factors to the severity of liver disease is not completely understood. In this study, apolipoprotein E-deficient (ApoE-/-) mice were evaluated to define potential effects of hypercholesterolemia on the severity of carbon tetrachloride (CCl4)-induced liver injury. Under baseline conditions, hypercholesterolemic ApoE-/- mice showed increased hepatic oxidative stress (SOD activity/4-hydroxy-2-nonenal immunostaining) and higher hepatic TGF-beta1, MCP-1, and TIMP-1 expression than wild-type control mice. After CCl4 challenge, ApoE-/- mice exhibited exacerbated steatosis (Oil Red O staining), necroinflammation (hematoxylin-eosin staining), macrophage infiltration (F4/80 immunohistochemistry), and fibrosis (Sirius red staining and alpha-smooth muscle actin immunohistochemistry) and more severe liver injury [alanine aminotransferase (ALT) and aspartate aminotransferase] than wild-type controls. Direct correlations were identified between serum cholesterol and hepatic steatosis, fibrosis, and ALT levels. These changes did not reflect the usual progression of the disease in ApoE-/- mice, since exacerbated liver injury was not present in untreated age-paired ApoE-/- mice. Moreover, hepatic cytochrome P-450 expression was unchanged in ApoE-/- mice. To explore potential mechanisms, cell types relevant to liver pathophysiology were exposed to selected cholesterol-oxidized products. Incubation of hepatocytes with a mixture of oxysterols representative of those detected by GC-MS in livers from ApoE-/- mice resulted in a concentration-dependent increase in total lipoperoxides and SOD activity. In hepatic stellate cells, oxysterols increased IL-8 secretion through a NF-kappaB-independent mechanism and upregulated TIMP-1 expression. In macrophages, oxysterols increased TGF-beta1 secretion and MCP-1 expression in a concentration-dependent manner. Oxysterols did not compromise cell viability. Taken together, these findings demonstrate that hypercholesterolemic mice are sensitized to liver injury and that cholesterol-derived products (i.e., oxysterols) are able to induce proinflammatory and profibrogenic mechanisms in liver cells.
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Affiliation(s)
- Natàlia Ferré
- Department of Biochemistry and Molecular Genetics, Liver Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Universitat de Barcelona, Barcelona, Spain
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Vejux A, Malvitte L, Lizard G. Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis. Braz J Med Biol Res 2008; 41:545-56. [DOI: 10.1590/s0100-879x2008000700001] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2008] [Accepted: 07/04/2008] [Indexed: 02/01/2023] Open
Affiliation(s)
- A. Vejux
- Université de Nice Sophia Antipolis, France
| | - L. Malvitte
- Hôpital Général, France; Faculté des Sciences Gabriel, France
| | - G. Lizard
- Faculté des Sciences Gabriel, France
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Biasi F, Mascia C, Poli G. The contribution of animal fat oxidation products to colon carcinogenesis, through modulation of TGF-beta1 signaling. Carcinogenesis 2008; 29:890-4. [PMID: 18453540 DOI: 10.1093/carcin/bgn106] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
It is now unanimously accepted that neoplastic cells tend to become less susceptible to the growth regulatory effects of transforming growth factor-beta1 (TGF-beta1), mainly because of reduced expression and/or activity of TGF-beta1-specific receptors, as reported for many human cancers including colon cancer. Consequently, a sustained increase of TGF-beta1 in the intestinal mucosa, like that caused by inflammatory processes and/or high dietary intake of animal fat, might become crucial for the progression of a neoplastic clone. In fact, this proapoptotic and prodifferentiating cytokine could eliminate neoplastic cells still susceptible to TGF-beta1's antiproliferative action (TGF-beta1 receptor-positive cells), indirectly favoring the expansion of TGF-beta1 resistant ones (TGF-beta1 receptors deficient or negative cells). The actual concentration of TGF-beta1 in the colonic mucosa undergoing neoplastic transformation is still debated, and the phase of the relevant carcinogenetic process in which a reduced susceptibility to this antiproliferative molecule first occurs has not been precisely established yet. However, no doubt that TGF-beta1 level and activity may be upregulated in cells of the macrophage lineage by animal fat oxidation products, such as oxysterols and aldehydes, as reviewed here. But phagocytes as well as fibroblasts constitutively express TGF-beta1 and are accumulating in tumor-associated stroma. Thus, upregulation of this cytokine system within colonic tumor-associated stroma by excess dietary intake of cholesterol and n-6 polyunsaturated fatty acids appears as a primary mechanism of cancer progression at least in neoplastic lesions of the digestive tract.
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Affiliation(s)
- Fiorella Biasi
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Regione Gonzole 10, 10043 Orbassano, Torino, Italy
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TGFbeta1 expression in colonic mucosa: modulation by dietary lipids. GENES AND NUTRITION 2007; 2:233-43. [PMID: 18850178 DOI: 10.1007/s12263-007-0053-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Accepted: 06/10/2007] [Indexed: 12/22/2022]
Abstract
Transforming growth factor beta1 (TGFbeta1) is fundamental to maintain the intestinal epithelial cell homeostasis through its control action on cell proliferation, differentiation and apoptosis. TGFbeta1 dysregulation has been observed in several chronic human diseases, including ulcerative colitis, Crohn's disease and colon carcinoma. In the first two conditions, a marked oxidative stress is consistently present, while in the third one, levels of reactive oxygen species tend to be significantly lower than in the surrounding normal tissue. Lipid-derived compounds such as the aldehyde 4-hydroxynonenal (HNE) or cholesterol oxidation products (oxysterols) were shown able to induce expression and synthesis of TGFbeta1, an event which can be detrimental or beneficial, essentially depending on its actual intensity. Understanding how specific dietary lipids may influence the complex molecular signaling underlying this cytokine expression, may provide new indications for therapeutic and preventive strategies in inflammatory bowel diseases and colon carcinoma.
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37
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Redondo S, Santos-Gallego CG, Tejerina T. TGF-β1: a novel target for cardiovascular pharmacology. Cytokine Growth Factor Rev 2007; 18:279-86. [PMID: 17485238 DOI: 10.1016/j.cytogfr.2007.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Transforming growth factor beta-1 (TGF-beta1) plays a key role in cardiovascular disease by a process which allows the loss of its protective properties. The first therapeutic attempt to restore its function by selectively designed novel drugs are being made. In addition, it has been recognized that the TGF-beta1 pathway is involved in the vascular mechanism of action of some current clinical drugs, such as acetylsalicylic acid, thiazolidinediones and statins. The aim of this paper is to review the possible value of TGF-beta1 as both a disease marker and a therapeutical target for cardiovascular disease.
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Affiliation(s)
- Santiago Redondo
- Department of Pharmacology, School of Medicine, Universidad Complutense de Madrid Av Complutense s/n, Madrid, Spain
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38
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Carter CJ. Convergence of genes implicated in Alzheimer's disease on the cerebral cholesterol shuttle: APP, cholesterol, lipoproteins, and atherosclerosis. Neurochem Int 2006; 50:12-38. [PMID: 16973241 DOI: 10.1016/j.neuint.2006.07.007] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 06/30/2006] [Accepted: 07/11/2006] [Indexed: 11/24/2022]
Abstract
Polymorphic genes associated with Alzheimer's disease (see ) delineate a clearly defined pathway related to cerebral and peripheral cholesterol and lipoprotein homoeostasis. They include all of the key components of a glia/neurone cholesterol shuttle including cholesterol binding lipoproteins APOA1, APOA4, APOC1, APOC2, APOC3, APOD, APOE and LPA, cholesterol transporters ABCA1, ABCA2, lipoprotein receptors LDLR, LRP1, LRP8 and VLDLR, and the cholesterol metabolising enzymes CYP46A1 and CH25H, whose oxysterol products activate the liver X receptor NR1H2 and are metabolised to esters by SOAT1. LIPA metabolises cholesterol esters, which are transported by the cholesteryl ester transport protein CETP. The transcription factor SREBF1 controls the expression of most enzymes of cholesterol synthesis. APP is involved in this shuttle as it metabolises cholesterol to 7-betahydroxycholesterol, a substrate of SOAT1 and HSD11B1, binds to APOE and is tethered to LRP1 via APPB1, APBB2 and APBB3 at the cytoplasmic domain and via LRPAP1 at the extracellular domain. APP cleavage products are also able to prevent cholesterol binding to APOE. BACE cleaves both APP and LRP1. Gamma-secretase (PSEN1, PSEN2, NCSTN) cleaves LRP1 and LRP8 as well as APP and their degradation products control transcription factor TFCP2, which regulates thymidylate synthase (TS) and GSK3B expression. GSK3B is known to phosphorylate the microtubule protein tau (MAPT). Dysfunction of this cascade, carved out by genes implicated in Alzheimer's disease, may play a major role in its pathology. Many other genes associated with Alzheimer's disease affect cholesterol or lipoprotein function and/or have also been implicated in atherosclerosis, a feature of Alzheimer's disease, and this duality may well explain the close links between vascular and cerebral pathology in Alzheimer's disease. The definition of many of these genes as risk factors is highly contested. However, when polymorphic susceptibility genes belong to the same signaling pathway, the risk associated with multigenic disease is better related to the integrated effects of multiple polymorphisms of genes within the same pathway than to variants in any single gene [Wu, X., Gu, J., Grossman, H.B., Amos, C.I., Etzel, C., Huang, M., Zhang, Q., Millikan, R.E., Lerner, S., Dinney, C.P., Spitz, M.R., 2006. Bladder cancer predisposition: a multigenic approach to DNA-repair and cell-cycle-control genes. Am. J. Hum. Genet. 78, 464-479.]. Thus, the fact that Alzheimer's disease susceptibility genes converge on a clearly defined signaling network has important implications for genetic association studies.
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39
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Ares MPS, Stollenwerk MM. Inflammatory effects of very low-density lipoprotein and fatty acids. Future Cardiol 2006; 2:315-23. [PMID: 19804089 DOI: 10.2217/14796678.2.3.315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
High plasma triacylglycerol (triglyceride, TG) levels is a risk factor for atherosclerosis. Very large lipoproteins, such as chylomicrons, alone are not considered atherogenic, but TG-rich remnant lipoproteins can penetrate into the vascular wall. Importantly, accumulating evidence suggests that all TG-rich lipoproteins stimulate cytokine expression in circulating monocytes. Very low-density lipoprotein (VLDL) stimulates monocyte adhesion to endothelial cells and expression of inflammatory genes in macrophages. Furthermore, fatty acids released from large lipoproteins can stimulate both vascular cells and circulating monocytes. It is likely that fatty acids released from TG-rich lipoproteins contribute to atherogenesis, but the role of fatty acids in ischemic heart disease is not as direct as that of cholesterol. Fatty acids influence plasma lipoprotein levels and either stimulate or suppress numerous cellular functions relevant to atherogenesis. While certain n-3 fatty acids are good for health, most other medium- to long-chain fatty acids appear to promote inflammation in cell culture studies and need to be studied further. Nevertheless, the existing evidence supports the general conclusion that TG-rich lipoproteins and fatty acids greatly accelerate the progression of atherosclerosis. This may be because of their inflammatory effects.
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Affiliation(s)
- Mikko P S Ares
- Department of Clinical Sciences, Malmö University Hospital, Lund University, Sweden.
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40
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Leonarduzzi G, Gamba P, Sottero B, Kadl A, Robbesyn F, Calogero RA, Biasi F, Chiarpotto E, Leitinger N, Sevanian A, Poli G. Oxysterol-induced up-regulation of MCP-1 expression and synthesis in macrophage cells. Free Radic Biol Med 2005; 39:1152-61. [PMID: 16214031 DOI: 10.1016/j.freeradbiomed.2005.06.024] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Revised: 06/10/2005] [Accepted: 06/13/2005] [Indexed: 11/22/2022]
Abstract
To investigate the proinflammatory potential of cholesterol and cholesterol oxidation products (oxysterols), which are present in oxidized low-density lipoproteins, foam cells, and fibrotic plaque, we used an in vitro model mimicking the challenge of macrophage cells by the cholesterol accumulating within the central core of atheroma. A biologically representative oxysterol mixture was shown to be potentially able to sustain a chronic inflammatory process within the vascular wall by up-regulating the expression of defined proinflammatory genes. In particular, expression and synthesis of the major chemokine for monocytes/macrophages, namely monocyte chemotactic protein-1 (MCP-1), were consistently increased when cells of the macrophage lineage (U937 cell line) were incubated with this mixture. On the contrary, an identical concentration of unoxidized cholesterol in no case modified expression or synthesis of the chemokine. Up-regulated expression and synthesis of MCP-1 by the oxysterol mixture was clearly dependent on a net increment of phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and nuclear factor kappaB (NF-kappaB) nuclear binding. The results indicate that cholesterol may contribute to the progression of atherosclerotic lesions by strongly up-regulating crucial proinflammatory factors like MCP-1, but only after having been oxidized to oxysterols.
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Affiliation(s)
- Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, University of Turin, S. Luigi Hospital, 10043 Orbassano (Turin), Italy
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41
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Leonarduzzi G, Chiarpotto E, Biasi F, Poli G. 4-Hydroxynonenal and cholesterol oxidation products in atherosclerosis. Mol Nutr Food Res 2005; 49:1044-9. [PMID: 16270277 DOI: 10.1002/mnfr.200500090] [Citation(s) in RCA: 306] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
4-Hydroxynonenal (HNE) is by far the most investigated aldehydic end-product of oxidative breakdown of membrane n-6 polyunsaturated fatty acids. Its potential involvement in the pathogenesis of atherosclerosis has been corroborated by its consistent detection in both oxidized LDL and fibrotic plaque in humans. HNE has been shown to activate both macrophage and smooth muscle cells, i.e. the two key cell types in chronic inflammatory processes characterized by excessive fibrogenesis. By signalling to the nucleus, the aldehyde may up-regulate in these cells both expression and synthesis of monocyte chemotactic protein 1 (MCP-1) and transforming growth factor beta1 (TGFbeta1). Oxysterols, namely 27 carbon atoms oxidation products of cholesterol, are found in relatively high amount in LDL from hypercholesterolemic individuals and are consistently detectable in foam cells and necrotic core of human atherosclerotic lesion. As for HNE, the challenge of cells of the macrophage lineage with a mixture of oxysterols like that detectable in hypercholesterolemic individuals led to a marked overexpression of TGFbeta1 and MCP-1. Both HNE and oxysterols then appear to be candidates for a primary role in the progression of the atherosclerotic process.
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42
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Abstract
Nutritional, or dietary oxidative stress denotes a disturbance of the redox state resulting from excess oxidative load or from inadequate nutrient supply favoring prooxidant reactions. Low intake or impaired availability of dietary antioxidants including vitamins E and C, carotenoids, polyphenols, and other micronutrients (e.g., selenium) weakens the antioxidant network. Postprandial oxidative stress, as a subform of nutritional oxidative stress, ensues from sustained postprandial hyperlipidemia and/or hyperglycemia and is associated with a higher risk for atherosclerosis, diabetes, and obesity. In Western societies, a significant part of the day is spent in the postprandial state. Unsaturated fatty acids incorporated into LDL and oxidized LDL are an atherogenic factor. Lipid hydroperoxides present in the diet are absorbed, contributing to the prooxidant load. In hyperlipidemic and hyperglycemic subjects, endothelium-dependent vasodilation is impaired in the postprandial state, making postprandial oxidative stress an important factor modulating cardiovascular risk. Postprandial oxidative stress is attenuated when dietary antioxidants are supplied together with a meal rich in oxidized or oxidizable lipids. Ingestion of dietary polyphenols, e.g., from wine, cocoa, or tea, improves endothelial dysfunction and lowers the susceptibility of LDL lipids to oxidation. Polyphenols affect endothelial function not solely as antioxidants but also as modulatory signaling molecules.
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Affiliation(s)
- Helmut Sies
- Institut für Biochemie und Molekularbiologie I, Universität Düsseldorf, Postfach 101007, D-40001 Düsseldorf, Germany.
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43
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Hansson M, Wikvall K, Babiker A. Regulation of sterol 27-hydroxylase in human monocyte-derived macrophages: up-regulation by transforming growth factor β1. Biochim Biophys Acta Mol Cell Biol Lipids 2005; 1687:44-51. [PMID: 15708352 DOI: 10.1016/j.bbalip.2004.11.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2004] [Revised: 10/04/2004] [Accepted: 11/03/2004] [Indexed: 01/22/2023]
Abstract
Regulatory mechanisms for human CYP27A1 enzyme have not yet been fully investigated. Our approach was to add different hormones and cytokines to cultured human monocyte-derived macrophages, and assess the effects on the CYP27A1 by measuring the production of 27-hydroxylated cholesterol in the media. Of the different hormones and cytokines tested, only transforming growth factor beta1 (TGF-beta1) had a clear effect on CYP27A1. Further experiments showed a significant increase in 27-hydroxylated cholesterol products (27-hydroxycholesterol and 3beta-hydroxy-5-cholestenoic acid). A concomitant increase in CYP27A1 mRNA levels was also seen and this positive effect was confirmed using a human CYP27A1 luciferase reporter gene expressed in HepG2 cells. Experiments with progressive deletion/luciferase reporter gene constructs indicated that a TGF-beta1 responsive sequence might be localized in a region about 400 bp upstream of the CYP27A1 translation start. The possibility is discussed that induction of CYP27A1 by TGF-beta1 may be responsible for some of the anti-atherogenic properties of this cytokine.
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Affiliation(s)
- Magnus Hansson
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska University Hospital at Huddinge, SE-141 86 Stockholm, Sweden
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44
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Sottero B, Gamba P, Longhi M, Robbesyn F, Abuja PM, Schaur RJ, Poli G, Leonarduzzi G. Expression and synthesis of TGFbeta1 is induced in macrophages by 9-oxononanoyl cholesterol, a major cholesteryl ester oxidation product. Biofactors 2005; 24:209-16. [PMID: 16403982 DOI: 10.1002/biof.5520240125] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Within the broad variety of compounds generated via oxidative reactions in low density lipoproteins (LDL) and subsequently found in the atherosclerotic plaque, are aldehydes still esterified to the parent lipid and termed core-aldehydes. The most represented cholesterol core-aldehyde in LDL is 9-oxononanoyl cholesterol (9-ONC), an oxidation product of cholesteryl linoleate. Here we report that 9-ONC, at concentration actually detectable in biological material, significantly up-regulates the expression and the synthesis of the pro-fibrogenic cytokine transforming growth factor beta1 (TGFbeta1) by cultured macrophages. As previously demonstrated for other lipid oxidation products present in LDL, namely a biologically representative mixture of oxysterols and the unesterified aldehyde 4-hydroxynonenal, these effects on TGFbeta1 by 9-ONC further points to LDL lipid oxidation as a powerful source of pro-fibrogenic stimuli.
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Affiliation(s)
- Barbara Sottero
- Department of Clinical and Biological Sciences, University of Torino, S. Luigi Hospital, Orbassano, Torino, Italy
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45
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Leonarduzzi G, Biasi F, Chiarpotto E, Poli G. Trojan horse-like behavior of a biologically representative mixture of oxysterols. Mol Aspects Med 2004; 25:155-67. [PMID: 15051324 DOI: 10.1016/j.mam.2004.02.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Oxysterols, 27-carbon atoms cholesterol oxidation products, are consistently detectable in minimally oxidized low density lipoproteins (oxLDLs) and accumulate in the core of fibrotic plaques. Several oxysterols of pathophysiological interest have been shown to possess many and diverse biochemical activities. In particular, 7-ketocholesterol (7K), a major cholesterol oxide both in oxLDLs and in atherosclerotic lesions, is able to lead vascular cells to apoptosis. Indeed, when 7K is added to cells of the macrophage lineage, in a concentration range actually detectable in hypercholesterolemic patients, a marked apoptotic effect was observed. However, when identical concentrations of 7K are given to the same cells in a mixture with other oxysterols, also detectable in human low density lipoprotein (LDL), cell apoptosis was dramatically reduced. Of note, identical amounts of unoxidized cholesterol did not show any significant pro-apoptotic effect. With the aim to investigate the mechanisms underlying the quenching of 7K-dependent apoptosis by the oxysterol mixture, we found that the combined oxysterol mixture counteracted the ability of 7K given alone to strongly increase the steady-state level of reactive oxygen species (ROS) in macrophages as well as the up-regulation of the pro-apoptotic factor p21 and the triggering of the mitochondria-dependent pathway of apoptosis. Competition among oxysterols, apparently at NADPH oxidase level, diminishes the macrophage ROS production and direct toxicity that is evoked by defined oxysterols, as for instance, 7-ketocholesterol.
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Affiliation(s)
- Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Regione Gonzole, 10, 10043 Orbassano, Torino, Italy
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Souidi M, Dubrac S, Parquet M, Volle DH, Lobaccaro JMA, Mathé D, Combes O, Scanff P, Lutton C, Aigueperse J. Les oxystérols : métabolisme, rôles biologiques et pathologies associées. ACTA ACUST UNITED AC 2004; 28:279-93. [PMID: 15094678 DOI: 10.1016/s0399-8320(04)94919-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Maâmar Souidi
- Département de Protection de la santé de l'Homme et de Dosimétrie, Section Autonome de Radiobiologie Appliquée à la Médecine, Institut de Radioprotection et de Sûreté Nucléaire, IRSN, B.P No 17, 92262 Fontenay-aux-roses Cedex
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47
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Biasi F, Leonarduzzi G, Vizio B, Zanetti D, Sevanian A, Sottero B, Verde V, Zingaro B, Chiarpotto E, Poli G. Oxysterol mixtures prevent proapoptotic effects of 7-ketocholesterol in macrophages: implications for proatherogenic gene modulation. FASEB J 2004; 18:693-5. [PMID: 14977888 DOI: 10.1096/fj.03-0401fje] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Oxysterols are common components of oxidized low-density lipoprotein and accumulate in the core of fibrotic plaques as a mixture of cholesterol and cholesteryl ester oxidation products. The proapoptotic effects of a biologically representative mixture of oxysterols was compared with equimolar amounts of 7-ketocholesterol and unoxidized cholesterol. The oxysterol mixture in a concentration range actually detectable in hypercholesterolemic patients did not stimulate programmed cell death in cultivated murine macrophages. Unoxidized cholesterol also produced no effect. By contrast, when given alone, 7-ketocholesterol strongly stimulated the mitochondrial pathway of apoptosis with cytochrome c release, caspase-9 activation, and eventually caspase-3 activation. Subsequent experiments showed that when 7-ketocholesterol was administered to cells together with another oxysterol, namely 7betaOH-cholesterol, the strong proapoptotic effect of 7-ketocholesterol was markedly attenuated. As regards the mechanism underlying this quenching, we found that the combined oxysterol treatment counteracted the ability of 7-ketocholesterol, when administered alone, to strongly up-regulate the steady-state levels of reactive oxygen species (ROS) without interfering with sterol uptake. Furthermore, this increase in intracellular ROS appeared to be responsible for the up-regulation of proapoptotic factor, p21, after treatment with 7-ketocholesterol but not in cells challenged with the oxysterol mixture. Competition among oxysterols, apparently at the level of NADPH oxidase, diminishes the ROS induction and direct toxicity that is evoked by specific oxysterols. As a consequence, a more subtle gene modulation by oxysterols becomes facilitated in vascular cells.
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Affiliation(s)
- Fiorella Biasi
- Department of Clinical and Biological Sciences, University of Torino, S. Luigi Gonzaga Hospital, Torino, Italy
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Maguire L, Konoplyannikov M, Ford A, Maguire AR, O'Brien NM. Comparison of the cytotoxic effects of beta-sitosterol oxides and a cholesterol oxide, 7beta-hydroxycholesterol, in cultured mammalian cells. Br J Nutr 2003; 90:767-75. [PMID: 13129445 DOI: 10.1079/bjn2003956] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Phytosterols are plant sterols found in foods such as oils, nuts and vegetables. Phytosterols, in the same way as cholesterol, contain a double bond and are susceptible to oxidation. The objective of the present study was to assess the potential toxic effects of beta-sitosterol oxides on U937 cells. The effects of increasing concentrations (0-120 microm) of beta-sitosterol oxides on cellular cytotoxicity, apoptosis, antioxidant status and genotoxicity was assessed over 12, 24 and 48 h exposure periods. Following 12 h, the viability of cells treated with 120 microm-beta-sitosterol oxides was reduced to 51.7 % relative to control. At 24 and 48 h, both 60 and 120 microm-beta-sitosterol oxides caused a significant decrease in cell viability. For comparison, a decrease in viability of cells treated with a cholesterol oxide, 7beta-hydroxycholesterol (7beta-OH, 30 microm), was evident at 24 h. An increase in apoptotic cells, assessed using Hoechst 33342, indicates that the mode of cell death in U937 cells following exposure to 7beta-OH (30 microm) and beta-sitosterol oxides (60 and 120 microm) was by apoptosis. The increase in apoptotic cells after 12 h following treatment with 120 microm-beta-sitosterol oxides was accompanied by a decrease in cellular glutathione. Similarly, 7beta-OH (30 microm) treatment resulted in decreased glutathione at 12 h. Catalase activity was not affected by any of the treatments. beta-Sitosterol oxides had no genotoxic effects on U937 and V79 cells as assessed by the comet and sister chromatid exchange assays respectively. In general, the results indicate that thermally oxidised derivatives of beta-sitosterol demonstrate similar biological effects as 7beta-OH in U937 cells, but at higher concentrations.
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Affiliation(s)
- Lindsay Maguire
- Department of Food and Nutritional Sciences, University College, Cork, Republic of Ireland
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49
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Leonarduzzi G, Sottero B, Poli G. Oxidized products of cholesterol: dietary and metabolic origin, and proatherosclerotic effects (review). J Nutr Biochem 2002; 13:700-710. [PMID: 12550054 DOI: 10.1016/s0955-2863(02)00222-x] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Cholesterol oxidation products, termed oxysterols, are increasingly considered of potential interest in the pathogenesis of atherosclerotic lesions. Of dietary or endogenous origin, oxysterols may occur in significant amounts in low density lipoprotein (LDL) particles, especially in hypercholesterolemic subjects. They likely contribute to the uptake of modified LDL by scavenger receptors and some of them finally accumulate in the subintimal space of major arteries; here cholesterol oxides may favor the perpetuation of a chronic inflammatory state, through their ability to trigger irreversible damage of vascular cells with consequent activation of phagocytes. Furthermore, practically all oxysterols of major pathophysiologic interest have been shown to markedly up-regulate expression and synthesis of adhesion molecules, inflammatory cytokines and chemokines. Cholesterol oxidation thus appears to be an important biochemical pathway through which it exerts toxic, inflammatory and finally atherogenic effects.
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Affiliation(s)
- Gabriella Leonarduzzi
- Department of Clinical and Biological Sciences, University of Turin, S. Luigi Gonzaga Hospital, 10043 (Turin), Orbassano, Italy
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50
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Ares MPS. Atherosclerosis: cell biology and lipoproteins. Curr Opin Lipidol 2002; 13:581-3. [PMID: 12352023 DOI: 10.1097/00041433-200210000-00016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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