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Melton HJ, Zhang Z, Deng HW, Wu L, Wu C. MIMOSA: a resource consisting of improved methylome prediction models increases power to identify DNA methylation-phenotype associations. Epigenetics 2024; 19:2370542. [PMID: 38963888 PMCID: PMC11225927 DOI: 10.1080/15592294.2024.2370542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 06/12/2024] [Indexed: 07/06/2024] Open
Abstract
Although DNA methylation (DNAm) has been implicated in the pathogenesis of numerous complex diseases, from cancer to cardiovascular disease to autoimmune disease, the exact methylation sites that play key roles in these processes remain elusive. One strategy to identify putative causal CpG sites and enhance disease etiology understanding is to conduct methylome-wide association studies (MWASs), in which predicted DNA methylation that is associated with complex diseases can be identified. However, current MWAS models are primarily trained using the data from single studies, thereby limiting the methylation prediction accuracy and the power of subsequent association studies. Here, we introduce a new resource, MWAS Imputing Methylome Obliging Summary-level mQTLs and Associated LD matrices (MIMOSA), a set of models that substantially improve the prediction accuracy of DNA methylation and subsequent MWAS power through the use of a large summary-level mQTL dataset provided by the Genetics of DNA Methylation Consortium (GoDMC). Through the analyses of GWAS (genome-wide association study) summary statistics for 28 complex traits and diseases, we demonstrate that MIMOSA considerably increases the accuracy of DNA methylation prediction in whole blood, crafts fruitful prediction models for low heritability CpG sites, and determines markedly more CpG site-phenotype associations than preceding methods. Finally, we use MIMOSA to conduct a case study on high cholesterol, pinpointing 146 putatively causal CpG sites.
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Affiliation(s)
- Hunter J. Melton
- Department of Statistics, Florida State University, Tallahassee, FL, USA
| | - Zichen Zhang
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Hong-Wen Deng
- Center of Bioinformatics and Genomics, Tulane University, New Orleans, LA, USA
| | - Lang Wu
- Center of Bioinformatics and Genomics, Tulane University, New Orleans, LA, USA
| | - Chong Wu
- Cancer Epidemiology Division, University of Hawaii Cancer Center, Honolulu, HI, USA
- Institute for Data Science in Oncology, The UT MD Anderson Cancer Center
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2
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Melton HJ, Zhang Z, Deng HW, Wu L, Wu C. MIMOSA: A resource consisting of improved methylome imputation models increases power to identify DNA methylation-phenotype associations. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.03.20.23287418. [PMID: 36993614 PMCID: PMC10055581 DOI: 10.1101/2023.03.20.23287418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Although DNA methylation has been implicated in the pathogenesis of numerous complex diseases, the exact methylation sites that play key roles in these processes remain elusive. One strategy to identify putative causal CpG sites and enhance disease etiology understanding is to conduct methylome-wide association studies (MWASs), in which predicted DNA methylation that is associated with complex diseases can be identified.However, current MWAS models are primarily trained by using the data from single studies, thereby limiting the methylation prediction accuracy and the power of subsequent association studies. Here, we introduce a new resource, MWAS Imputing Methylome Obliging Summary-level mQTLs and Associated LD matrices (MIMOSA), a set of models that substantially improve the prediction accuracy of DNA methylation and subsequent MWAS power through the use of a large, summary-level mQTL dataset provided by the Genetics of DNA Methylation Consortium (GoDMC). With the analyses of GWAS (genome-wide association study) summary statistics for 28 complex traits and diseases, we demonstrate that MIMOSA considerably increases the accuracy of DNA methylation prediction in whole blood, crafts fruitful prediction models for low heritability CpG sites, and determines markedly more CpG site-phenotype associations than preceding methods. Finally, we use MIMOSA to conduct a case study in high cholesterol, pinpointing 146 putatively causal CpG sites.
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Affiliation(s)
| | - Zichen Zhang
- Department of Statistics, Florida State University
| | - Hong-Wen Deng
- Cancer Epidemiology Division, University of Hawaii Cancer Center
| | - Lang Wu
- Center of Bioinformatics and Genomics, Tulane University
| | - Chong Wu
- Department of Biostatistics, University of Texas MD Anderson Cancer Center
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3
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Yokoyama S. HDL Receptor in Schistosoma japonicum Mediating Egg Embryonation: Potential Molecular Basis for High Prevalence of Cholesteryl Ester Transfer Protein Deficiency in East Asia. Front Cell Dev Biol 2022; 10:807289. [PMID: 35372338 PMCID: PMC8968628 DOI: 10.3389/fcell.2022.807289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/21/2022] [Indexed: 12/03/2022] Open
Abstract
Schistosomiasis is a life-threatening parasitic disease caused by blood flukes, Schistosomes. In its intestinal type, the parasites reside in visceral/portal veins of the human hosts and lay eggs to excrete in feces via intestinal tracts, and some of the aberrant eggs plug into the liver via the portal blood flow. Ectopic growth of these eggs causes fatal granulomatosis and cirrhosis of the liver. The parasites ingest nutrients from the host blood plasma by using nonspecific and specific transport via their body surface and alimentary tracts. It is especially important for the female adults to obtain lipid molecules because they synthesize neither fatty acids nor sterols and yet produce egg yolk. Low-density lipoprotein receptors have been identified in the body of the Schistosomes but their functions in the parasite life cycle have not clearly been characterized. On the other hand, CD36-related protein was identified in the body and the eggs of Asian blood fluke, Schistosoma japonicum, and characterized as a molecule that mediates selective uptake of cholesteryl ester from the host plasma high-density lipoproteins (HDLs). This reaction was shown crucial for their eggs to grow to miracidia. Interestingly, abnormal large HDL generated in lack of cholesteryl ester transfer protein (CETP) is a poor substrate for this reaction, and, therefore, CETP deficiency resists pathogenic ectopic growth of the aberrant parasite eggs in the liver. This genetic mutation is exclusively found in East Asia, overlapping with the current and historic regions of Schistosoma japonicum epidemic, so that this infection could be related to high prevalence of CETP deficiency in East Asia.
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Affiliation(s)
- Shinji Yokoyama
- Food and Nutritional Sciences, Chubu University, Kasugai, Japan
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Qiao L, Wang HF, Xiang L, Ma J, Zhu Q, Xu D, Zheng H, Peng JQ, Zhang S, Lu HX, Chen WQ, Zhang Y. Deficient Chaperone-Mediated Autophagy Promotes Lipid Accumulation in Macrophage. J Cardiovasc Transl Res 2021; 14:661-669. [PMID: 32285315 PMCID: PMC8397667 DOI: 10.1007/s12265-020-09986-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/06/2020] [Indexed: 01/22/2023]
Abstract
Chaperone-mediated autophagy (CMA) serves as a critical upstream regulator of lipophagy and lipid metabolism in hepatocyte. However, the role of CMA in lipid metabolism of macrophage, the typical component of atherosclerotic plaque, remains unclear. In our study, LAMP-2A (L2A, a CMA marker) was reduced in macrophages exposed to high dose of oleate, and lipophagy was impaired in advanced atherosclerosis in ApoE (-/-) mice. Primary peritoneal macrophages isolated from macrophage-specific L2A-deficient mice exhibited pronounced intracellular lipid accumulation. Lipid regulatory enzymes, including long-chain-fatty-acid-CoA ligase 1 (ACSL1) and lysosomal acid lipase (LAL), were increased and reduced in L2A-KO macrophage, respectively. Other lipid-related proteins, such as SR-A, SR-B (CD36), ABCA1, or PLIN2, were not associated with increased lipid content in L2A-KO macrophage. In conclusion, deficient CMA promotes lipid accumulation in macrophage probably by regulating enzymes involved in lipid metabolism. CMA may represent a novel therapeutic target to alleviate atherosclerosis by promoting lipid metabolism. Graphical abstract.
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Affiliation(s)
- Lei Qiao
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
| | - He-Feng Wang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
- Qilu Hospital of Shandong University (Qingdao), No. 758 Hefei Road, Qingdao, 266035, China
| | - Lei Xiang
- Department of Cardiology, Sishui County People's Hospital, Sishui, 273200, Shandong, China
| | - Jing Ma
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
| | - Qiang Zhu
- Department of clinical laboratory, Sishui County People's Hospital, Sishui, 273200, Shandong, China
| | - Dan Xu
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
| | - Hui Zheng
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
| | - Jie-Qiong Peng
- School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan, China
| | - Sen Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
- Qilu Hospital of Shandong University (Qingdao), No. 758 Hefei Road, Qingdao, 266035, China
| | - Hui-Xia Lu
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China
| | - Wen-Qiang Chen
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China.
| | - Yun Zhang
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, 250012, Jinan, China.
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Herrero-Fernandez B, Gomez-Bris R, Somovilla-Crespo B, Gonzalez-Granado JM. Immunobiology of Atherosclerosis: A Complex Net of Interactions. Int J Mol Sci 2019; 20:E5293. [PMID: 31653058 PMCID: PMC6862594 DOI: 10.3390/ijms20215293] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/21/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
Cardiovascular disease is the leading cause of mortality worldwide, and atherosclerosis the principal factor underlying cardiovascular events. Atherosclerosis is a chronic inflammatory disease characterized by endothelial dysfunction, intimal lipid deposition, smooth muscle cell proliferation, cell apoptosis and necrosis, and local and systemic inflammation, involving key contributions to from innate and adaptive immunity. The balance between proatherogenic inflammatory and atheroprotective anti-inflammatory responses is modulated by a complex network of interactions among vascular components and immune cells, including monocytes, macrophages, dendritic cells, and T, B, and foam cells; these interactions modulate the further progression and stability of the atherosclerotic lesion. In this review, we take a global perspective on existing knowledge about the pathogenesis of immune responses in the atherosclerotic microenvironment and the interplay between the major innate and adaptive immune factors in atherosclerosis. Studies such as this are the basis for the development of new therapies against atherosclerosis.
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Affiliation(s)
- Beatriz Herrero-Fernandez
- LamImSys Lab. Instituto de Investigación Hospital 12 de Octubre (imas12), 28041 Madrid, Spain.
- Departamento de Fisiología. Facultad de Medicina. Universidad Autónoma de Madrid (UAM), 28029 Madrid, Spain.
| | - Raquel Gomez-Bris
- LamImSys Lab. Instituto de Investigación Hospital 12 de Octubre (imas12), 28041 Madrid, Spain.
| | | | - Jose Maria Gonzalez-Granado
- LamImSys Lab. Instituto de Investigación Hospital 12 de Octubre (imas12), 28041 Madrid, Spain.
- Departamento de Fisiología. Facultad de Medicina. Universidad Autónoma de Madrid (UAM), 28029 Madrid, Spain.
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain.
- CIBER de Enfermedades Cardiovasculares, 28029 Madrid, Spain.
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6
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Korber M, Klein I, Daum G. Steryl ester synthesis, storage and hydrolysis: A contribution to sterol homeostasis. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:1534-1545. [DOI: 10.1016/j.bbalip.2017.09.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 08/25/2017] [Accepted: 09/05/2017] [Indexed: 02/01/2023]
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Abstract
High-density lipoprotein (HDL) and low-density lipoprotein (LDL), as human endogenous lipoprotein particles, have low toxicity, high selectivity, and good safety. They can avoid the recognition and clearance of human reticuloendothelial system. These synthetic lipoproteins (sLPs) have been attracted extensive attention as the nanovectors for tumor-targeted drug and gene delivery. Herein, recent advances in the field of anticancer based on these two lipid proteins and recombinant lipoproteins (rLPs) as target delivery vectors were analyzed and discussed.
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Affiliation(s)
- Xueqin Zhang
- Active Carbohydrate Research Center, College of Chemistry, Chongqing Normal University, Chongqing, PR China
| | - Gangliang Huang
- Active Carbohydrate Research Center, College of Chemistry, Chongqing Normal University, Chongqing, PR China
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8
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Chistiakov DA, Melnichenko AA, Myasoedova VA, Grechko AV, Orekhov AN. Mechanisms of foam cell formation in atherosclerosis. J Mol Med (Berl) 2017; 95:1153-1165. [DOI: 10.1007/s00109-017-1575-8] [Citation(s) in RCA: 287] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 07/04/2017] [Accepted: 07/28/2017] [Indexed: 12/21/2022]
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9
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Mimura J, Itoh K. Role of Nrf2 in the pathogenesis of atherosclerosis. Free Radic Biol Med 2015; 88:221-232. [PMID: 26117321 DOI: 10.1016/j.freeradbiomed.2015.06.019] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 06/03/2015] [Accepted: 06/06/2015] [Indexed: 01/01/2023]
Abstract
Atherosclerosis is a chronic inflammatory disease of the vascular arterial walls. A number of studies have revealed the biological and genetic bases of atherosclerosis, and over 100 genes influence atherosclerosis development. Nrf2 plays an important role in oxidative stress response and drug metabolism, but the Nrf2 signaling pathway is closely associated with atherosclerosis development. During atherosclerosis progression, Nrf2 signaling modulates many physiological and pathophysiological processes, such as lipid homeostasis regulation, foam cell formation, macrophage polarization, redox regulation and inflammation. Interestingly, Nrf2 exhibits both pro- and anti-atherogenic effects in experimental animal models. These observations make the Nrf2 pathway a promising target to prevent atherosclerosis.
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Affiliation(s)
- Junsei Mimura
- Department of Stress Response Science, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan.
| | - Ken Itoh
- Department of Stress Response Science, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
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10
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Chistiakov DA, Bobryshev YV, Orekhov AN. Macrophage-mediated cholesterol handling in atherosclerosis. J Cell Mol Med 2015; 20:17-28. [PMID: 26493158 PMCID: PMC4717859 DOI: 10.1111/jcmm.12689] [Citation(s) in RCA: 321] [Impact Index Per Article: 35.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 08/19/2015] [Indexed: 02/06/2023] Open
Abstract
Formation of foam cells is a hallmark at the initial stages of atherosclerosis. Monocytes attracted by pro-inflammatory stimuli attach to the inflamed vascular endothelium and penetrate to the arterial intima where they differentiate to macrophages. Intimal macrophages phagocytize oxidized low-density lipoproteins (oxLDL). Several scavenger receptors (SR), including CD36, SR-A1 and lectin-like oxLDL receptor-1 (LOX-1), mediate oxLDL uptake. In late endosomes/lysosomes of macrophages, oxLDL are catabolysed. Lysosomal acid lipase (LAL) hydrolyses cholesterol esters that are enriched in LDL to free cholesterol and free fatty acids. In the endoplasmic reticulum (ER), acyl coenzyme A: cholesterol acyltransferase-1 (ACAT1) in turn catalyses esterification of cholesterol to store cholesterol esters as lipid droplets in the ER of macrophages. Neutral cholesteryl ester hydrolases nCEH and NCEH1 are involved in a secondary hydrolysis of cholesterol esters to liberate free cholesterol that could be then out-flowed from macrophages by cholesterol ATP-binding cassette (ABC) transporters ABCA1 and ABCG1 and SR-BI. In atherosclerosis, disruption of lipid homoeostasis in macrophages leads to cholesterol accumulation and formation of foam cells.
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Affiliation(s)
- Dimitry A Chistiakov
- Division of Laboratory Medicine, Department of Molecular Genetic Diagnostics and Cell Biology, Institute of Pediatrics, Research Center for Children's Health, Moscow, Russia
| | - Yuri V Bobryshev
- Faculty of Medicine and St Vincent's Centre for Applied Medical Research, University of New South Wales, Sydney, NSW, Australia.,School of Medicine, University of Western Sydney, Campbelltown, NSW, Australia.,Institute for Atherosclerosis Research, Skolkovo Innovative Center, Moscow, Russia
| | - Alexander N Orekhov
- Institute for Atherosclerosis Research, Skolkovo Innovative Center, Moscow, Russia.,Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, Russian Academy of Sciences, Moscow, Russia.,Department of Biophysics, Biological Faculty, Moscow State University, Moscow, Russia
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11
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Hamamoto J, Soejima K, Naoki K, Yasuda H, Hayashi Y, Yoda S, Nakayama S, Satomi R, Terai H, Ikemura S, Sato T, Arai D, Ishioka K, Ohgino K, Betsuyaku T. Methylation-induced downregulation of TFPI-2 causes TMPRSS4 overexpression and contributes to oncogenesis in a subset of non-small-cell lung carcinoma. Cancer Sci 2014; 106:34-42. [PMID: 25414083 PMCID: PMC4317784 DOI: 10.1111/cas.12569] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 10/14/2014] [Accepted: 11/04/2014] [Indexed: 12/13/2022] Open
Abstract
We identified transmembrane protease, serine 4 (TMPRSS4) as a putative, druggable target by screening surgically resected samples from 90 Japanese non-small-cell lung cancer (NSCLC) patients using cDNA microarray. TMPRSS4 has two druggable domains and was upregulated in 94.5% of the lung cancer specimens. Interestingly, we found that TMPRSS4 expression was associated with tissue factor pathway inhibitor 2 (TFPI-2) expression in these clinical samples. In contrast to TMPRSS4, TFPI-2 expression was downregulated in NSCLC samples. The in vitro induction of TFPI-2 in lung cancer cell lines decreased the expression of TMPRSS4mRNA levels. Reporter assay showed that TFPI-2 inhibited transcription of TMPRSS4, although partially. Knockdown of TMPRSS4 reduced the proliferation rate in several lung cancer cell lines. When lung cancer cell lines were treated with 5-aza-2′-deoxycytidine or trichostatin A, their proliferation rate and TMPRSS4mRNA expression levels were also reduced through the upregulation of TFPI-2 by decreasing its methylation in vitro. The TFPI-2 methylation level in the low TMPRSS4 group appeared to be significantly low in NSCLC samples (P = 0.02). We found a novel molecular mechanism that TFPI-2 negatively regulates cell growth by inhibiting transcription of TMPRSS4. We suggest that TMPRSS4 is upregulated by silencing of TFPI-2 through aberrant DNA methylation and contributes to oncogenesis in NSCLC.
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Affiliation(s)
- Junko Hamamoto
- Department of Pulmonary Medicine, School of Medicine, Keio University, Tokyo, Japan
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12
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Gabriel BM, Pugh J, Pruneta-Deloche V, Moulin P, Ratkevicius A, Gray SR. The effect of high intensity interval exercise on postprandial triacylglycerol and leukocyte activation--monitored for 48 h post exercise. PLoS One 2013; 8:e82669. [PMID: 24349333 PMCID: PMC3857256 DOI: 10.1371/journal.pone.0082669] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 10/26/2013] [Indexed: 01/20/2023] Open
Abstract
Postprandial phenomenon are thought to contribute to atherogenesis alongside activation of the immune system. A single bout of high intensity interval exercise attenuates postprandial triacylglycerol (TG), although the longevity and mechanisms underlying this observation are unknown. The aims of this study were to determine whether this attenuation in postprandial TG remained 2 days after high intensity interval exercise, to monitor markers of leukocyte activation and investigate the underlying mechanisms. Eight young men each completed two three day trials. On day 1: subjects rested (Control) or performed 5 x 30 s maximal sprints (high intensity interval exercise). On day 2 and 3 subjects consumed high fat meals for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TG, glucose and TG-rich lipoprotein (TRL)-bound LPL-dependent TRL-TG hydrolysis (LTTH). Flow cytometry was used to evaluate granulocyte, monocyte and lymphocyte CD11b and CD36 expression. On day 2 after high intensity interval exercise TG area under the curve was lower (P<0.05) (7.46±1.53 mmol/l/7h) compared to the control trial (9.47±3.04 mmol/l/7h) with no differences during day 3 of the trial. LTTH activity was higher (P<0.05) after high intensity interval exercise, at 2 hours of day 2, compared to control. Granulocyte, monocyte and lymphocyte CD11b expression increased with time over day 2 and 3 of the study (P<0.0001). Lymphocyte and monocyte CD36 expression decreased with time over day 2 and 3 (P<0.05). There were no differences between trials in CD11b and CD36 expression on any leukocytes. A single session of high intensity interval exercise attenuated postprandial TG on day 2 of the study, with this effect abolished by day 3.The reduction in postprandial TG was associated with an increase in LTTH. High intensity interval exercise had no effect on postprandial responses of CD11b or CD36.
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Affiliation(s)
| | - Jamie Pugh
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, United Kingdom
| | | | - Philippe Moulin
- Endocrinology Department, Hopital Louis Pradel, University Lyon, Lyon, France
| | - Aivaras Ratkevicius
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Stuart Robert Gray
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- * E-mail:
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13
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Dai Y, Su W, Ding Z, Wang X, Mercanti F, Chen M, Raina S, Mehta JL. Regulation of MSR-1 and CD36 in macrophages by LOX-1 mediated through PPAR-γ. Biochem Biophys Res Commun 2013; 431:496-500. [DOI: 10.1016/j.bbrc.2013.01.029] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 01/09/2013] [Indexed: 12/20/2022]
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14
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Tong M, Han BB, Holpuch AS, Pei P, He L, Mallery SR. Inherent phenotypic plasticity facilitates progression of head and neck cancer: endotheliod characteristics enable angiogenesis and invasion. Exp Cell Res 2013; 319:1028-42. [PMID: 23370231 DOI: 10.1016/j.yexcr.2013.01.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 01/15/2013] [Accepted: 01/18/2013] [Indexed: 10/27/2022]
Abstract
The presence of the EMT (epithelial-mesenchymal transition), EndMT (endothelial-mesenchymal transition) and VM (vasculogenic mimicry) demonstrates the multidirectional extent of phenotypic plasticity in cancers. Previous findings demonstrating the crosstalk between head and neck squamous cell carcinoma (HNSCC) and vascular endothelial growth factor (VEGF) imply that HNSCC cells share some functional commonalities with endothelial cells. Our current results reveal that cultured HNSCC cells not only possess endothelial-specific markers, but also display endotheliod functional features including low density lipoprotein uptake, formation of tube-like structures on Matrigel and growth state responsiveness to VEGF and endostatin. HNSCC cell subpopulations are also highly responsive to transforming growth factor-β1 and express its auxiliary receptor, endoglin. Furthermore, the endotheliod characteristics observed in vitro recapitulate phenotypic features observed in human HNSCC tumors. Conversely, cultured normal human oral keratinocytes and intact or ulcerated human oral epithelia do not express comparable endotheliod characteristics, which imply that assumption of endotheliod features is restricted to transformed keratinocytes. In addition, this phenotypic state reciprocity facilitates HNSCC progression by increasing production of factors that are concurrently pro-proliferative and pro-angiogenic, conserving cell energy stores by LDL internalization and enhancing cell mobility. Finally, recognition of this endotheliod phenotypic transition provides a solid rationale to evaluate the antitumorigenic potential of therapeutic agents formerly regarded as exclusively angiostatic in scope.
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Affiliation(s)
- Meng Tong
- Division of Oral Pathology and Radiology, The Ohio State University College of Dentistry, Columbus, OH 43210, USA.
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15
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Genomic DNA methylation changes in NYGGF4-overexpression 3T3-L1 adipocytes. Int J Mol Sci 2012; 13:15575-87. [PMID: 23443082 PMCID: PMC3546650 DOI: 10.3390/ijms131215575] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 11/06/2012] [Accepted: 11/16/2012] [Indexed: 12/21/2022] Open
Abstract
NYGGF4, an obesity-related gene, is proposed to be involved in the development of insulin resistance; however, the underlying molecular mechanisms remain unclear. In the present analysis, NimbleGen tiling arrays were used to determine the patterns of genomic DNA methylation at CpG islands and promoters in NYGGF4-overexpression adipocytes. A total of 2352 CpG dinucleotides in 2018 genes and 3490 CpG dinucleotides in 3064 genes were found to be hypermethylated or hypomethylated, respectively, in NYGGF4-overexpression adipocytes. Furthermore, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis revealed enrichment of biological processes associated with energy metabolism and signal transduction events, including the peroxisome proliferator-activated receptor gamma (PPARγ) signaling pathway, and mitogen-activated protein kinases(MAPK) and Ras homolog gene family, member A (RhoA) signaling. These data demonstrate that differentially methylated genes are significantly overrepresented in NYGGF4-overexpression adipocytes, providing valuable clues for further exploration of the role of NYGGF4 in insulin sensitivity regulation.
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16
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Su T, Zhao L, Ruan X, Zuo G, Gong J. Synergistic effect of scavenger receptor A and low-density lipoprotein receptor on macrophage foam cell formation under inflammatory stress. Mol Med Rep 2012; 7:37-42. [PMID: 23139052 DOI: 10.3892/mmr.2012.1170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Accepted: 03/19/2012] [Indexed: 11/06/2022] Open
Abstract
To provide experimental evidence for the effect of inflammation on cholesterol accumulation in macrophages, we investigated the expression of low-density lipoprotein receptor (LDL-R) and scavenger receptor A (SR-A) genes and proteins in the lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cell line. RAW264.7 cells were incubated in serum-free medium in the absence or presence of LDL alone, LDL+LPS and LPS alone. Intracellular cholesterol content, tumor necrosis factor α levels in the supernatants, mRNA and protein expression of LDL-R and SR-A in the treated cells were assessed by Oil Red O staining cholesterol enzymatic assay, enzyme-linked immunosorbent assay, semi-quantitative polymerase chain reaction and western blot analysis, respectively. Our results demonstrated that LPS was able to upregulate SR-A mRNA and protein expression, override LDL-R suppression induced by a high dose of LDL and increase LDL uptake by enhancing receptor expression, leading to foam cell formation in RAW264.7 cells. These findings suggest that the synergy of the upregulation of SR-A and dysregulation of LDL-R under inflammatory stress may contribute to macrophage-derived foam cell formation.
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Affiliation(s)
- Tianyi Su
- Chongqing Key Laboratory of Hepatobiliary Surgery and Department of Hepatobiliary Surgery, Second Affiliated Hospital to Chongqing Medical University, Chongqing, PR China
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17
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Vollmar B, Menger MD. The hepatic microcirculation: mechanistic contributions and therapeutic targets in liver injury and repair. Physiol Rev 2009; 89:1269-339. [PMID: 19789382 DOI: 10.1152/physrev.00027.2008] [Citation(s) in RCA: 352] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The complex functions of the liver in biosynthesis, metabolism, clearance, and host defense are tightly dependent on an adequate microcirculation. To guarantee hepatic homeostasis, this requires not only a sufficient nutritive perfusion and oxygen supply, but also a balanced vasomotor control and an appropriate cell-cell communication. Deteriorations of the hepatic homeostasis, as observed in ischemia/reperfusion, cold preservation and transplantation, septic organ failure, and hepatic resection-induced hyperperfusion, are associated with a high morbidity and mortality. During the last two decades, experimental studies have demonstrated that microcirculatory disorders are determinants for organ failure in these disease states. Disorders include 1) a dysregulation of the vasomotor control with a deterioration of the endothelin-nitric oxide balance, an arterial and sinusoidal constriction, and a shutdown of the microcirculation as well as 2) an overwhelming inflammatory response with microvascular leukocyte accumulation, platelet adherence, and Kupffer cell activation. Within the sequelae of events, proinflammatory mediators, such as reactive oxygen species and tumor necrosis factor-alpha, are the key players, causing the microvascular dysfunction and perfusion failure. This review covers the morphological and functional characterization of the hepatic microcirculation, the mechanistic contributions in surgical disease states, and the therapeutic targets to attenuate tissue injury and organ dysfunction. It also indicates future directions to translate the knowledge achieved from experimental studies into clinical practice. By this, the use of the recently introduced techniques to monitor the hepatic microcirculation in humans, such as near-infrared spectroscopy or orthogonal polarized spectral imaging, may allow an early initiation of treatment, which should benefit the final outcome of these critically ill patients.
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Affiliation(s)
- Brigitte Vollmar
- Institute for Experimental Surgery, University of Rostock, Rostock, Germany.
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18
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Beckmann N, Cannet C, Babin AL, Blé F, Zurbruegg S, Kneuer R, Dousset V. In vivo
visualization of macrophage infiltration and activity in inflammation using magnetic resonance imaging. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2009; 1:272-98. [DOI: 10.1002/wnan.16] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Nicolau Beckmann
- Global Imaging Group, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
| | - Catherine Cannet
- Global Imaging Group, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
| | - Anna Louise Babin
- Global Imaging Group, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
- Respiratory Diseases Department, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
- Sackler Institute of Pulmonary Pharmacology, King's College, London SE1 1UL, UK
| | - François‐Xavier Blé
- Respiratory Diseases Department, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
- Mouse Imaging Centre, Toronto Centre for Phenogenomics, Toronto, Canada M5T 3H7
| | - Stefan Zurbruegg
- Global Imaging Group, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
| | - Rainer Kneuer
- Global Imaging Group, Novartis Institutes for BioMedical Research, CH‐4056 Basel, Switzerland
| | - Vincent Dousset
- University Victor Segalen Bordeaux 2, EA 2966 Neurobiology of Myelin Disease Laboratory, CHU de Bordeaux, F‐33076 Bordeaux, France
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19
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Murao K, Yu X, Imachi H, Cao WM, Chen K, Matsumoto K, Nishiuchi T, Wong NCW, Ishida T. Hyperglycemia suppresses hepatic scavenger receptor class B type I expression. Am J Physiol Endocrinol Metab 2008; 294:E78-87. [PMID: 17957039 DOI: 10.1152/ajpendo.00023.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hyperglycemia is a major risk factor for atherosclerotic disease. Hepatic scavenger receptor class B type I (SR-BI) binds HDL particles that mediate reverse cholesterol transport and thus lowers the risk of atherosclerosis. Here we examined glucose regulation of SR-BI gene expression in both HepG2 cells and whole animals. Results showed that hepatic SR-BI mRNA, protein, and uptake of cholesterol from HDL were halved following 48 h of exposure to 22.4 vs. 5.6 mM glucose. As in the case of the cell culture model, hepatic expression of SR-BI was lower in diabetic rats than in euglycemic rats. Transcriptional activity of the human SR-BI promoter paralleled endogenous expression of the gene, and this activity was dependent upon the dose of glucose. Next, we used inhibitors of select signal transduction pathways to demonstrate that glucose suppression of SR-BI was sensitive to the p38 MAPK inhibitor. Expression of a constitutively active p38 MAPK inhibited SR-BI promoter activity in the presence or absence of glucose. A dominant-negative p38 MAPK abolished the inhibitory effect of glucose on promoter activity. Deletional analysis located a 50-bp fragment of the promoter that mediated the effects of glucose. Within this DNA fragment there were several specificity protein-1 (Sp1) binding sites, and cellular knockdown of Sp1 abrogated its suppression by glucose. Together, these results indicate that the glucose suppression of SR-B1 expression is partially mediated by the activation of the p38 MAPK-Sp1 pathway and raise the possibility that the inhibition of hepatic SR-BI expression under high-glucose conditions provides a mechanism for accelerated atherosclerosis in diabetics.
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Affiliation(s)
- Koji Murao
- Div. of Endocrinology and Metabolism, Dept. of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan.
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20
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Gustafsson B, Youens S, Louie AY. Development of contrast agents targeted to macrophage scavenger receptors for MRI of vascular inflammation. Bioconjug Chem 2006; 17:538-47. [PMID: 16536488 PMCID: PMC2556229 DOI: 10.1021/bc060018k] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Atherosclerosis is a leading cause of death in the U.S. Because there is a potential to prevent coronary and arterial disease through early diagnosis, there is a need for methods to image arteries in the subclinical stage as well as clinical stage using various noninvasive techniques, including magnetic resonance imaging (MRI). We describe a development of a novel MRI contrast agent targeted to plaques that will allow imaging of lesion formation. The contrast agent is directed to macrophages, one of the earliest components of developing plaques. Macrophages are labeled through the macrophage scavenger receptor A, a macrophage specific cell surface protein, using an MRI contrast agent derived from scavenger receptor ligands. We have synthesized and characterized these contrast agents with a range of relaxivities. In vitro studies show that the targeted contrast agent accumulates in macrophages, and solution studies indicate that micromolar concentrations are sufficient to produce contrast in an MR image. Cell toxicity and initial biodistribution studies indicate low toxicity, no detectable retention in normal blood vessels, and rapid clearance from blood. The promising performance of this contrast agent targeted toward vascular inflammation opens doors to tracking of other inflammatory diseases such as tumor immunotherapy and transplant acceptance using MRI.
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Affiliation(s)
| | | | - Angelique Y. Louie
- Department of Biomedical Engineering, University of California, Davis, CA 95616
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21
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Nahmias Y, Casali M, Barbe L, Berthiaume F, Yarmush ML. Liver endothelial cells promote LDL-R expression and the uptake of HCV-like particles in primary rat and human hepatocytes. Hepatology 2006; 43:257-65. [PMID: 16440337 DOI: 10.1002/hep.21016] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Low-density lipoprotein (LDL) is an important carrier of plasma cholesterol and triglycerides whose concentration is regulated by the liver parenchymal cells. Abnormal LDL regulation is thought to cause atherosclerosis, while viral binding to LDL has been suggested to facilitate hepatitis C infection. Primary hepatocytes quickly lose the ability to clear LDL during in vitro culture. Here we show that the coculture of hepatocytes with liver sinusoidal endothelial cells (LSEC) significantly increases the ability of hepatocytes to uptake LDL in vitro. LDL uptake does not increase when hepatocytes are cocultured with other cell types such as fibroblasts or umbilical vein endothelial cells. We find that LSECs induce the hepatic expression of the LDL receptor and the epidermal growth factor receptor. In addition, while hepatocytes in single culture did not take up hepatitis C virus (HCV)-like particles, the hepatocytes cocultured with LSECs showed a high level of HCV-like particle uptake. We suggest that coculture with LSECs induces the emergence of a sinusoidal surface in primary hepatocytes conducive to the uptake of HCV-like particles. In conclusion, our findings describe a novel model of polarized hepatocytes in vitro that can be used for the study of LDL metabolism and hepatitis C infection.
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Affiliation(s)
- Yaakov Nahmias
- Center for Engineering in Medicine/Department of Surgery, Massachusetts General Hospital, Shriners Burns Hospital, Harvard Medical School, Boston, MA 02114, USA
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22
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Pedro-Botet J, Jericó C. Etiopatogenia de la arteriosclerosis. Aspectos celulares y moleculares del daño vascular. Aten Primaria 2005. [DOI: 10.1016/s0212-6567(05)70579-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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23
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Greaves DR, Gordon S. Thematic review series: the immune system and atherogenesis. Recent insights into the biology of macrophage scavenger receptors. J Lipid Res 2004; 46:11-20. [PMID: 15548472 DOI: 10.1194/jlr.r400011-jlr200] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Scavenger receptors were originally defined by their ability to bind and internalize modified lipoproteins. Macrophages express at least six structurally different cell surface receptors for modified forms of LDL that contribute to foam cell formation in atherosclerosis. In addition to their role in the pathology of atherosclerosis, macrophage scavenger receptors, especially SR-A, play critical roles in innate immunity, apoptotic cell clearance, and tissue homeostasis. In this review, we highlight recent advances in understanding the biology of macrophage scavenger receptors as pattern recognition receptors for both infectious nonself (pathogens) and modified self (apoptotic cells and modified LDL). We critically evaluate the potential of scavenger receptors and their ligands as targets for therapeutic intervention in human disease.
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Affiliation(s)
- David R Greaves
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom.
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24
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Tietge UJF, Cichon G, Büttner C, Genschel J, Heeren J, Gielow P, Grewe N, Dogar M, Beisiegel U, Manns MP, Lochs H, Burchert W, Schmidt HHJ. A sensitive noninvasive method for monitoring successful liver-directed gene transfer of the low-density lipoprotein receptor in Watanabe hyperlipidemic rabbits in vivo. Gene Ther 2004; 11:574-80. [PMID: 14724675 DOI: 10.1038/sj.gt.3302206] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Noninvasive tools to quantitate transgene expression directly are a prerequisite for clinical gene therapy. We established a method to determine location, magnitude, and duration of low-density lipoprotein (LDL) receptor (LDLR) transgene expression after adenoviral gene transfer into LDLR-deficient Watanabe hypercholesterolemic rabbits by following tissue uptake of intravenously injected (111)In-labeled LDL using a scintillation camera. Liver-specific tracer uptake was calculated by normalizing the counts measured over the liver to counts measured over the heart that represent the circulating blood pool of the tracer (liver/heart (L/H) ratio). Our results indicate that the optimal time point for transgene imaging is 4 h after the tracer injection. Compared with control virus-injected rabbits, animals treated with the LDLR-expressing adenovirus showed seven-fold higher L/H ratios on day 6 after gene transfer, and had still 4.5-fold higher L/H ratios on day 30. This imaging method might be a useful strategy to obtain reliable data on functional transgene expression in clinical gene therapy trials of familial hypercholesterolemia.
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Affiliation(s)
- U J F Tietge
- Department of Medicine and NWFZ, Charité Campus Mitte, Humboldt University, Berlin, Germany
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25
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Sampson MJ, Davies IR, Braschi S, Ivory K, Hughes DA. Increased expression of a scavenger receptor (CD36) in monocytes from subjects with Type 2 diabetes. Atherosclerosis 2003; 167:129-34. [PMID: 12618277 DOI: 10.1016/s0021-9150(02)00421-5] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Uptake of modified low density lipoprotein (LDL) by monocyte-macrophages is mediated by the scavenger receptor CD36, which is upregulated in vitro by high glucose concentrations and oxidatively modified LDL. We hypothesised that monocyte CD36 expression would be higher in Type 2 diabetes, and would increase during acute hyperglycaemia. Sixteen subjects with Type 2 diabetes and 11 controls underwent a 75 g oral glucose load. Monocyte CD36 expression (by laser flow cytometry), plasma LDL diene conjugates, plasma LDL hydroxyoctadecadienoic acid-13 (a peroxisome proliferator activator receptor gamma agonist) were measured at 0, 2 and 4 h. Mean monocyte CD36 expression at baseline was 34% higher in the diabetes group (P=0.01), did not change during acute hyperglycaemia and plasma LDL conjugated diene concentration was the only variable directly related to CD36 expression (F=4.53; P=0.05; r=0.51). Higher baseline CD36 expression in Type 2 diabetes could reflect increased post-transcriptional efficiency of CD36 mRNA in response to chronic hyperglycaemia and could be a proatherogenic mechanism in Type 2 diabetes.
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MESH Headings
- Adult
- Aged
- Blood Glucose/analysis
- CD36 Antigens/genetics
- CD36 Antigens/metabolism
- Case-Control Studies
- Cohort Studies
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/physiopathology
- Female
- Gene Expression Regulation
- Glucose Tolerance Test
- Humans
- Lipoproteins, LDL/genetics
- Lipoproteins, LDL/metabolism
- Male
- Membrane Proteins
- Middle Aged
- Monocytes
- Probability
- RNA, Messenger/analysis
- Receptors, Immunologic/genetics
- Receptors, Immunologic/metabolism
- Receptors, Lipoprotein
- Receptors, Scavenger
- Reference Values
- Scavenger Receptors, Class B
- Sensitivity and Specificity
- Up-Regulation/genetics
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Affiliation(s)
- Michael J Sampson
- Bertram Diabetes Research Unit, Department of Endocrinology and Diabetes, Norfolk and Norwich University Hospital NHS Trust, UK.
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26
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Urano F, Calfon M, Yoneda T, Yun C, Kiraly M, Clark SG, Ron D. A survival pathway for Caenorhabditis elegans with a blocked unfolded protein response. J Cell Biol 2002; 158:639-46. [PMID: 12186849 PMCID: PMC2174003 DOI: 10.1083/jcb.200203086] [Citation(s) in RCA: 163] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The unfolded protein response (UPR) counteracts stress caused by unprocessed ER client proteins. A genome-wide survey showed impaired induction of many UPR target genes in xbp-1 mutant Caenorhabditis elegans that are unable to signal in the highly conserved IRE1-dependent UPR pathway. However a family of genes, abu (activated in blocked UPR), was induced to higher levels in ER-stressed xbp-1 mutant animals than in ER-stressed wild-type animals. RNA-mediated interference (RNAi) inactivation of a representative abu family member, abu-1 (AC3.3), activated the ER stress marker hsp-4::gfp in otherwise normal animals and killed 50% of ER-stressed ire-1 and xbp-1 mutant animals. Abu-1(RNAi) also enhanced the effect of inactivation of sel-1, an ER-associated protein degradation gene. The nine abu genes encode highly related type I transmembrane proteins whose lumenal domains have sequence similarity to a mammalian cell surface scavenger receptor of endothelial cells that binds chemically modified extracellular proteins and directs their lysosomal degradation. Our findings that ABU-1 is an intracellular protein located within the endomembrane system that is induced by ER stress in xbp-1 mutant animals suggest that ABU proteins may interact with abnormal ER client proteins and this function may be particularly important in animals with an impaired UPR.
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Affiliation(s)
- Fumihiko Urano
- Skirball Institute, New York University School of Medicine, 540 First Avenue, New York, NY 10016, USA
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27
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Tsuneyama K, Harada K, Kono N, Sasaki M, Saito T, Gershwin ME, Ikemoto M, Arai H, Nakanuma Y. Damaged interlobular bile ducts in primary biliary cirrhosis show reduced expression of glutathione-S-transferase-pi and aberrant expression of 4-hydroxynonenal. J Hepatol 2002; 37:176-83. [PMID: 12127421 DOI: 10.1016/s0168-8278(02)00105-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS Chronic inflammation induces oxidative stress by producing reactive oxygen species. We investigated how the oxidative stress associated with chronic cholangitis induce bile duct damages in primary biliary cirrhosis. METHODS The intracellular status of lipid peroxidation due to oxidative stress and that of glutathione, an endogenous cytoprotective molecule, were examined in primary biliary cirrhosis and controls by immunostaining of 4-hydroxynonenal and glutathione-S-transferase-pi. The former is a by-product of lipid peroxidation, and the latter is involved in the formation of intracellular glutathione. RESULTS In the damaged bile ducts of primary biliary cirrhosis, glutathione-S-transferase-pi expression was markedly reduced, reflecting reduction of intracellular glutathione, and perinuclear expression of 4-hydroxynonenal was frequent, reflecting active lipid peroxidation associated with biliary epithelial damages. There was diffuse/luminal expression of 4-hydroxynonenal in the bile ducts frequent in primary biliary cirrhosis and controls, likely reflecting absorption of 4-hydroxynonenal, also a component of oxidized low-density lipoprotein, from bile via scavenger receptor class B type 1 on biliary epithelium. CONCLUSIONS The data suggest that lipid peroxidation in the bile ducts with reduced expression of glutathione-S-transferase-pi, may be an important pathologic process leading to the bile duct damage of primary biliary cirrhosis.
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Affiliation(s)
- Koichi Tsuneyama
- Department of Human Pathology, Kanazawa University Graduate School of Medicine, Japan
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28
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Tailleux A, Torpier G, Bonnefont-Rousselot D, Lestavel S, Lemdani M, Caudeville B, Furman C, Foricher R, Gardes-Albert M, Lesieur D, Rolando C, Teissier E, Fruchart JC, Clavey V, Fievet C, Duriez P. Daily melatonin supplementation in mice increases atherosclerosis in proximal aorta. Biochem Biophys Res Commun 2002; 293:1114-23. [PMID: 12051775 DOI: 10.1016/s0006-291x(02)00336-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Considerable evidence supports the hypothesis that LDL oxidation plays an important role in atherosclerosis. Even though high melatonin doses inhibit LDL oxidation in vitro, the effect of melatonin on atherosclerosis has never been studied. We have demonstrated that the feeding of hypercholesterolemic mice with an atherogenic diet supplemented with melatonin highly increases the surface of atherosclerotic lesions in the proximal aorta. These observations occur without detectable lipidic or glucidic phenotype alteration. Melatonin treatment increased highly the sensitivity of atherogenic lipoprotein to Cu(2+) and gamma-radiolysis generated oxyradical ex vivo oxidation during the fasting period. Moreover, these altered lipoproteins were less recognized by the LDL receptor metabolic pathway of murine fibroblasts while they transferred many more cholesteryl esters to murine macrophages. This study suggests that caution should be taken as regards high melatonin dosage in hypercholesterolemic patients.
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Affiliation(s)
- Anne Tailleux
- Département d'Athérosclérose, Inserm U545, Institut Pasteur, 1 rue du Pr Calmette, 59019 Lille, France
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29
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Hegele RA. Monogenic dyslipidemias: window on determinants of plasma lipoprotein metabolism. Am J Hum Genet 2001; 69:1161-77. [PMID: 11704922 PMCID: PMC1235529 DOI: 10.1086/324647] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2001] [Accepted: 09/27/2001] [Indexed: 12/19/2022] Open
Affiliation(s)
- R A Hegele
- John P. Robarts Research Institute, London, Ontario, Canada.
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30
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Dent SB, Peterson CT, Brace LD, Swain JH, Reddy MB, Hanson KB, Robinson JG, Alekel DL. Soy protein intake by perimenopausal women does not affect circulating lipids and lipoproteins or coagulation and fibrinolytic factors. J Nutr 2001; 131:2280-7. [PMID: 11533267 DOI: 10.1093/jn/131.9.2280] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Soy protein favorably alters serum lipids and lipoproteins in hypercholesterolemic individuals, thereby reducing cardiovascular disease risk. The primary purpose was to determine the effect of soy protein (40 g/d) on circulating lipids and lipoproteins or coagulation and fibrinolytic factors in normocholesterolemic and mildly hypercholesterolemic perimenopausal women. We also determined the contribution of coagulation and fibrinolytic and other factors (e.g., body size and composition; serum estrogens, ferritin, iron; dietary intake) to lipid profiles. Subjects were randomly assigned to treatment: isoflavone-rich soy (n = 24), isoflavone-poor soy (n = 24), or whey control (n = 21) protein. We measured circulating lipids and lipoproteins at baseline, wk 12 and wk 24, and coagulation/fibrinolytic factors at baseline and wk 24. Coagulation and fibrinolytic factors were not adversely affected by treatment. Treatment did not alter lipid profiles in mildly hypercholesterolemic (n = 30) or in all subjects combined. Time significantly (P < 0.001) affected serum total cholesterol, triacylglycerol, LDL cholesterol and HDL cholesterol concentrations. We could not attribute changes over time to various factors, but at baseline accounted for 57% of the variability in HDL cholesterol (P < or = 0.0001) and for 50% in the total to HDL cholesterol ratio (P < or = 0.0001). Dietary vitamin E and % energy from fat had positive effects, whereas plasma plasminogen activator inhibitor-1, fibrinogen, body weight and serum ferritin had negative effects on HDL and total to HDL cholesterol. Isoflavone-rich or isoflavone-poor soy protein had no effect on lipid profiles or coagulation and fibrinolytic factors, whereas the effect of time suggested that the hormonal milieu during the menopausal transition may have overridden any detectable treatment effect on lipids. The relationship between coagulation factors and serum lipids should be examined further as indices of cardiovascular disease risk in midlife women.
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Affiliation(s)
- S B Dent
- Department of Food Science and Human Nutrition, Human Metabolic Unit, Center for Designing Foods to Improve Nutrition, Iowa State University, Ames, IA 50011, USA
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31
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Kharbanda R, Vallance P. Coronary artery disease--from bench to bedside. J R Soc Med 2001; 94:61-4. [PMID: 11234200 PMCID: PMC1297907 DOI: 10.1177/014107680109400203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- R Kharbanda
- Centre for Clinical Pharmacology & Therapeutics, University College London, Rayne Institute, 5 University Street, London WC1E 6JJ, UK
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