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Wang X, Luo X, Wang Z, Wang Y, Zhao J, Bian L. Identification of cancer stemness and M2 macrophage-associated biomarkers in lung adenocarcinoma. Heliyon 2023; 9:e19114. [PMID: 37662825 PMCID: PMC10472008 DOI: 10.1016/j.heliyon.2023.e19114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 08/06/2023] [Accepted: 08/10/2023] [Indexed: 09/05/2023] Open
Abstract
Objective Cancer stemness and M2 macrophages are intimately linked to the prognosis of lung adenocarcinoma (LUAD). For this reason, this investigation sought to identify the key genes relevant to cancer stemness and M2 macrophages, explore the relationship between these genes and clinical characteristics, and determine the potential mechanism. Methods LUAD transcriptomic data was analyzed from The Cancer Genome Atlas (TCGA) as well as the Gene Expression Omnibus databases. Differential expression analysis was performed to discern abnormally expressed genes between LUAD and control samples in TCGA cohort. The Cell type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm was applied to determine varyingly infiltrated immune cells in LUAD compared with the control samples in TCGA cohort. Weighted correlation network analysis (WGCNA) was performed to identify genes associated with mRNA expression-based stemness index (mRNAsi) and M2 macrophages. Least absolute shrinkage and selection operator (LASSO), RandomForest (RF) and support vector machine-recursive feature elimination (SVM-RFE) machine learning methods were conducted to detect gene signatures. Global survival evaluation (Kaplan-Meier curve) was applied to investigate the relationship between gene signatures and the survival time of LUAD patients. Receiver operating characteristic (ROC) curves were produced to define biomarkers relevant to diagnosis. Gene Set Enrichment Analysis (GSEA) was performed to probe the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to diagnostic biomarkers. The public single-cell dataset of LUAD (GSE123902) was used to investigate the expression differences of diagnostic biomarkers in various cell types in LUAD. Real-time quantitative PCR (qRT-PCR) was performed to confirm key genes in lung adenocarcinoma cells. Results A total of 5,410 differentialy expressed genes (DEGs) as well as 15 differentially infiltrated immune cells were identified between LUAD and control sepcimens in TCGA cohort. Thirty-seven DEGs were associated with both M2 macrophages and mRNAsi according to the WGCNA analysis. Sixteen common gene signatures were obtained using three diverse algorithms. CBFA2T3, DENND3 and FCAMR were correlated to overall and disease-free survival of LUAD patients. ROC curves revealed that CBFA2T3 and DENND3 expression accurately classified LUAD and control samples. The results of single cell related analysis showed that two diagnostic biomarkers expressions were differed between the different tissue sources in M2-like macrophages. QRT-PCR demonstrated the mRNA expressions of CBFA2T3 and DENND3 were upregulated in lung adenocarcinoma cells A549 and H2122. Conclusion Our study identified CBFA2T3 and DENND3 as key genes associated with mRNAsi and M2 macrophages in LUAD and investigated the potential molecular mechanisms underlying this relationship.
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Affiliation(s)
| | | | - ZhiYuan Wang
- The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - YangHao Wang
- The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Juan Zhao
- The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Li Bian
- The First Affiliated Hospital of Kunming Medical University, Kunming, China
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2
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Zhuo X, Luo H, Lei R, Lou X, Bian J, Guo J, Luo H, Zhang X, Jiao Q, Gong W. Association between Intestinal Microecological Changes and Atherothrombosis. Microorganisms 2023; 11:1223. [PMID: 37317197 DOI: 10.3390/microorganisms11051223] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 06/16/2023] Open
Abstract
Atherosclerosis (AS) is a chronic inflammatory disease of large- and medium-sized arteries that causes ischemic heart disease, strokes, and peripheral vascular disease, collectively called cardiovascular disease (CVD), and is the leading cause of CVD resulting in a high rate of mortality in the population. AS is pathological by plaque development, which is caused by lipid infiltration in the vessel wall, endothelial dysfunction, and chronic low-grade inflammation. Recently, more and more scholars have paid attention to the importance of intestinal microecological disorders in the occurrence and development of AS. Intestinal G-bacterial cell wall lipopolysaccharide (LPS) and bacterial metabolites, such as oxidized trimethylamine (TMAO) and short-chain fatty acids (SCFAs), are involved in the development of AS by affecting the inflammatory response, lipid metabolism, and blood pressure regulation of the body. Additionally, intestinal microecology promotes the progression of AS by interfering with the normal bile acid metabolism of the body. In this review, we summarize the research on the correlation between maintaining a dynamic balance of intestinal microecology and AS, which may be potentially helpful for the treatment of AS.
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Affiliation(s)
- Xinyu Zhuo
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Hui Luo
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
- Hangzhou Institute of Cardiovascular Disease, Hangzhou 310000, China
| | - Rumei Lei
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Xiaokun Lou
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Jing Bian
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Junfeng Guo
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Hao Luo
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Xingwei Zhang
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
- Hangzhou Institute of Cardiovascular Disease, Hangzhou 310000, China
| | - Qibin Jiao
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
| | - Wenyan Gong
- Department of Clinical Medicine, Affiliated Hospital of Hangzhou Normal University, Hangzhou Normal University, Wenzhou Road, Gongshu District, Hangzhou 310000, China
- Hangzhou Institute of Cardiovascular Disease, Hangzhou 310000, China
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3
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Page MJ, Kell DB, Pretorius E. The Role of Lipopolysaccharide-Induced Cell Signalling in Chronic Inflammation. CHRONIC STRESS (THOUSAND OAKS, CALIF.) 2022; 6:24705470221076390. [PMID: 35155966 PMCID: PMC8829728 DOI: 10.1177/24705470221076390] [Citation(s) in RCA: 79] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 01/11/2022] [Indexed: 12/20/2022]
Abstract
Lipopolysaccharide (LPS) is the main structural component of the outer membrane of most Gram-negative bacteria and has diverse immunostimulatory and procoagulant effects. Even though LPS is well described for its role in the pathology of sepsis, considerable evidence demonstrates that LPS-induced signalling and immune dysregulation are also relevant in the pathophysiology of many diseases, characteristically where endotoxaemia is less severe. These diseases are typically chronic and progressive in nature and span broad classifications, including neurodegenerative, metabolic, and cardiovascular diseases. This Review reappraises the mechanisms of LPS-induced signalling and emphasises the crucial contribution of LPS to the pathology of multiple chronic diseases, beyond conventional sepsis. This perspective asserts that new ways of approaching chronic diseases by targeting LPS-driven pathways may be of therapeutic benefit in a wide range of chronic inflammatory conditions.
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Affiliation(s)
| | - Douglas B Kell
- Stellenbosch University, Stellenbosch, South Africa.,Institute of Integrative Biology, University of Liverpool, Liverpool, UK.,The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
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4
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Önal MA, Fentoğlu Ö, Aksoy F, Calapoğlu M, Varol E, Orhan H. Salivary levels of last generation specific pro-resolving lipid mediators (SPMs) (protectin and maresin) in patients with cardiovascular and periodontal disease: A case-control study. J Periodontal Res 2021; 56:606-615. [PMID: 33650687 DOI: 10.1111/jre.12861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 01/15/2021] [Accepted: 01/27/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND AND OBJECTIVE Periodontal disease and cardiovascular disease (CVD), which are both deemed to be triggered by inflammation, are recognized as public health problems. Evidence of host modulation via pro-resolving lipid shown in previous studies supports a two-way relationship between periodontitis and CVD. Last generation endogenous specific pro-resolution lipid mediators (SPMs) such as protectins (PDs) and maresins (MaRs) may have potential effects on inflammatory pathogenesis via activation and resolution mechanisms. Currently, there are no data on SPM levels in patients with CVD and periodontal disease. We aimed to evaluate salivary levels of PD and MaR in patients with CVD and periodontal disease. MATERIALS AND METHODS At total of 181 individuals comprising of 79 healthy controls (C) and 102 patients with diagnosed CVD were included cross-sectionally. Unstimulated total salivary samples were obtained, and clinical periodontal parameters were determined. Salivary levels of PD and MaR were evaluated by ELISA. The periodontal status of the study population was classified as gingivitis (g) or periodontitis (p). RESULTS Patients with CVD showed lower sociodemographic characteristics, increased clinical periodontal parameters (p < .05), decreased salivary PD (p < .001), and increased salivary MaR levels (p > .05). In the CVDg group, leukocyte, hemoglobin, hematocrit, and high-density lipoprotein values were higher (p < .05). The CVDp group had a higher neutrophil-to-lymphocyte ratio (p < .05). While the PD level was highest in the Cg group, MaR was highest in the CVDp group. The salivary levels of PD and MaR were independent of other confounders in CVD and periodontal disease (p > .05). CONCLUSION(S) PDs and MaRs may play effective roles in pathogenesis associated with worsening cardiometabolic and periodontal status. These SPMs could also be predictors for conversion from a healthy (systemically and periodontally) to diseased state (CVD and/or periodontitis). Elucidation of the role of SPMs in the relationship between periodontal disease and CVD will enable the development of new host modulation strategies in the prevention and treatment of both diseases, and may also constitute an important public health step by increasing the quality of life of patients with CVD and periodontal disease.
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Affiliation(s)
- Mehmet Artuğ Önal
- Department of Periodontology, Faculty of Dentistry, Süleyman Demirel University, Isparta, Turkey
| | - Özlem Fentoğlu
- Department of Periodontology, Faculty of Dentistry, Süleyman Demirel University, Isparta, Turkey
| | - Fatih Aksoy
- Department of Cardiology, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
| | - Mustafa Calapoğlu
- Department of Biochemistry, Faculty of Science, Süleyman Demirel University, Isparta, Turkey
| | - Ercan Varol
- Department of Cardiology, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
| | - Hikmet Orhan
- Department of Biostatistics and Medical Informatics, Faculty of Medicine, Süleyman Demirel University, Isparta, Turkey
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5
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Gao X, Chan PKS, Lui GCY, Hui DSC, Chu IMT, Sun X, Tsang MSM, Chan BCL, Lam CWK, Wong CK. Interleukin-38 ameliorates poly(I:C) induced lung inflammation: therapeutic implications in respiratory viral infections. Cell Death Dis 2021; 12:53. [PMID: 33414457 PMCID: PMC7790341 DOI: 10.1038/s41419-020-03283-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/11/2022]
Abstract
Interleukin-38 has recently been shown to have anti-inflammatory properties in lung inflammatory diseases. However, the effects of IL-38 in viral pneumonia remains unknown. In the present study, we demonstrate that circulating IL-38 concentrations together with IL-36α increased significantly in influenza and COVID-19 patients, and the level of IL-38 and IL-36α correlated negatively and positively with disease severity and inflammation, respectively. In the co-cultured human respiratory epithelial cells with macrophages to mimic lung microenvironment in vitro, IL-38 was able to alleviate inflammatory responses by inhibiting poly(I:C)-induced overproduction of pro-inflammatory cytokines and chemokines through intracellular STAT1, STAT3, p38 MAPK, ERK1/2, MEK, and NF-κB signaling pathways. Intriguingly, transcriptomic profiling revealed that IL-38 targeted genes were associated with the host innate immune response to virus. We also found that IL-38 counteracts the biological processes induced by IL-36α in the co-culture. Furthermore, the administration of recombinant IL-38 could mitigate poly I:C-induced lung injury, with reduced early accumulation of neutrophils and macrophages in bronchoalveolar lavage fluid, activation of lymphocytes, production of pro-inflammatory cytokines and chemokines and permeability of the alveolar-epithelial barrier. Taken together, our study indicates that IL-38 plays a crucial role in protection from exaggerated pulmonary inflammation during poly(I:C)-induced pneumonia, thereby providing the basis of a novel therapeutic target for respiratory viral infections.
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Affiliation(s)
- Xun Gao
- Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Paul Kay Sheung Chan
- Department of Microbiology, The Chinese University of Hong Kong, Hong Kong, China.,Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong, China
| | - Grace Chung Yan Lui
- Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong, China.,Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - David Shu Cheong Hui
- Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong, China.,Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - Ida Miu-Ting Chu
- Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Xiaoyu Sun
- Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China
| | - Miranda Sin-Man Tsang
- Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China.,Institute of Chinese Medicine and State Key Laboratory of Research on Bioactivities and Clinical Applications of Medicinal Plants, The Chinese University of Hong Kong, Hong Kong, China
| | - Ben Chung Lap Chan
- Institute of Chinese Medicine and State Key Laboratory of Research on Bioactivities and Clinical Applications of Medicinal Plants, The Chinese University of Hong Kong, Hong Kong, China
| | - Christopher Wai-Kei Lam
- Faculty of Medicine and State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau, China
| | - Chun-Kwok Wong
- Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong, China. .,Institute of Chinese Medicine and State Key Laboratory of Research on Bioactivities and Clinical Applications of Medicinal Plants, The Chinese University of Hong Kong, Hong Kong, China. .,Li Dak Sum Yip Yio Chin R & D Centre for Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China.
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6
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Wang Z, Cao K, Wang D, Hua B, Zhang H, Xie X. Cadmium sulfate induces apoptosis in planarians. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:39308-39316. [PMID: 32648224 DOI: 10.1007/s11356-020-09991-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 07/01/2020] [Indexed: 06/11/2023]
Abstract
With rapid socio-economic development, heavy metal pollution in water has become common and affects both environment and human health. Cadmium (Cd) has been recognized as one of the heavy metals which cause acute or chronic toxic effects if ingested. Although its toxicity is undisputed, the underlying molecular mechanisms in vivo are not fully understood. Planarians, a model organism famous for their regenerative prowess, have long been utilized to study the effects of chemical exposure. In this study, we observed apoptosis with TUNEL assay in planarians induced by cadmium sulfate (CdSO4) in a dose-dependent manner. The apoptosis-related genes were detected with quantitative RT-PCR. Significant changes in c-Myc, P53, and BcL-2 were indicated, which may play a partial role in the regulation of the process of apoptosis in the planarians. H&E staining showed that Cd had obvious biological toxicity in the planarians. Here, new insights on metal toxicity mechanisms are provided, contributing to understand how CdSO4 induces the pathological and physiological processes of apoptosis in the living bodies. Meanwhile, planarians are proved to be a freshwater pollution indicator and toxicological research model.
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Affiliation(s)
- Zhiyang Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Keqing Cao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Dan Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Bingjie Hua
- GeWu Medical Research Institute (GMRI), Xi'an, China
| | - Haiyan Zhang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China.
- GeWu Medical Research Institute (GMRI), Xi'an, China.
| | - Xin Xie
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China.
- GeWu Medical Research Institute (GMRI), Xi'an, China.
- Department of Translational Medicine, Institute of Integrated Medical Information, Xi'an, China.
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7
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Franke K, Pillai SY, Hoogenboezem M, Gijbels MJJ, Matlung HL, Geissler J, Olsman H, Pottgens C, van Gorp PJ, Ozsvar-Kozma M, Saito Y, Matozaki T, Kuijpers TW, Hendriks RW, Kraal G, Binder CJ, de Winther MPJ, van den Berg TK. SIRPα on Mouse B1 Cells Restricts Lymphoid Tissue Migration and Natural Antibody Production. Front Immunol 2020; 11:570963. [PMID: 33162986 PMCID: PMC7581795 DOI: 10.3389/fimmu.2020.570963] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/17/2020] [Indexed: 01/19/2023] Open
Abstract
The inhibitory immunoreceptor SIRPα is expressed on myeloid and neuronal cells and interacts with the broadly expressed CD47. CD47-SIRPα interactions form an innate immune checkpoint and its targeting has shown promising results in cancer patients. Here, we report expression of SIRPα on B1 lymphocytes, a subpopulation of murine B cells responsible for the production of natural antibodies. Mice defective in SIRPα signaling (SIRPαΔCYT mice) displayed an enhanced CD11b/CD18 integrin-dependent B1 cell migration from the peritoneal cavity to the spleen, local B1 cell accumulation, and enhanced circulating natural antibody levels, which was further amplified upon immunization with T-independent type 2 antigen. As natural antibodies are atheroprotective, we investigated the involvement of SIRPα signaling in atherosclerosis development. Bone marrow (SIRPαΔCYT>LDLR−/−) chimaeric mice developed reduced atherosclerosis accompanied by increased natural antibody production. Collectively, our data identify SIRPα as a unique B1 cell inhibitory receptor acting to control B1 cell migration, and imply SIRPα as a potential therapeutic target in atherosclerosis.
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Affiliation(s)
- Katka Franke
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | | | - Mark Hoogenboezem
- Sanquin Research and Landsteiner Laboratory, Department of Plasma Protein, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Marion J J Gijbels
- Department of Medical Biochemistry, Experimental Vascular Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Pathology, CARIM, Cardiovascular Research Institute Maastricht, GROW-School for Oncology and Developmental Biology, Maastricht University, Maastricht, Netherlands
| | - Hanke L Matlung
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Judy Geissler
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Hugo Olsman
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Chantal Pottgens
- Department of Medical Biochemistry, Experimental Vascular Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Patrick J van Gorp
- Department of Medical Biochemistry, Experimental Vascular Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Maria Ozsvar-Kozma
- Department of Laboratory Diagnostics, Medical University of Vienna, Vienna, Austria
| | - Yasuyuki Saito
- Division of Molecular and Cellular Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takashi Matozaki
- Division of Molecular and Cellular Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Taco W Kuijpers
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Pediatric Hematology, Immunology and Infectious Disease, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, Netherlands
| | - Georg Kraal
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Infection and Immunity Institute, Amsterdam, Netherlands
| | - Christoph J Binder
- Department of Laboratory Diagnostics, Medical University of Vienna, Vienna, Austria
| | - Menno P J de Winther
- Department of Medical Biochemistry, Experimental Vascular Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Institute for Cardiovascular Prevention (IPEK), Munich, Germany
| | - Timo K van den Berg
- Sanquin Research and Landsteiner Laboratory, Department of Blood Cell Research, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands.,Department of Molecular Cell Biology and Immunology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Infection and Immunity Institute, Amsterdam, Netherlands
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8
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Chen L, Qin L, Liu X, Meng X. CTRP3 Alleviates Ox-LDL-Induced Inflammatory Response and Endothelial Dysfunction in Mouse Aortic Endothelial Cells by Activating the PI3K/Akt/eNOS Pathway. Inflammation 2020; 42:1350-1359. [PMID: 30887395 DOI: 10.1007/s10753-019-00996-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
C1q/tumor necrosis factor-related protein-3 (CTRP3) is a novel, certified, adipokine that beneficially regulates metabolism and inflammation in the cardiovascular system. Atherosclerotic plaque rupturing and secondary thrombosis cause vascular disorders, such as myocardial infarction and unstable angina. However, the underlying role of CTRP3 in atherosclerosis remains unclear. In this study, we aimed to elucidate whether and how CTRP3 ameliorates inflammation and endothelial dysfunction caused by oxidized low-density lipoprotein (ox-LDL). We first confirmed that CTRP3 expression was inhibited in ApoE-/- mice, compared to normal mice. Then, pcDNA-CTRP3 and siCTRP3 were transfected into mouse aortic endothelial cells after ox-LDL stimulation, and we observed that enhanced CTRP3 remarkably downregulated CRP, TNF-α, IL-6, CD40, and CD40L. We also observed that overexpression of CTRP3 elevated cell activity and decreased lactated hydrogenase release, accompanied by a marked reduction in cell apoptosis induced by ox-LDL. Meanwhile, overexpressed CTRP3 caused a decrease in Ang II, ICAM-1, and VCAM-1 expression, and it restored the balance between ET-1 and NO. Mechanism analysis confirmed that incremental CTRP3 upregulated p-PI3K, p-Akt, and p-eNOS expression, indicating that CTRP3 facilitated activation of the PI3K/Akt/eNOS pathway. On the contrary, siCTRP3 exerted the opposite effect to this activation. Blocking these pathways using LY294002 or L-NAME attenuated the protective role of CTRP3. Overall, these results suggest that CTRP3 can efficiently inhibit the inflammatory response and endothelial dysfunction induced by ox-LDL in mouse aortic endothelial cells, perhaps by activating the PI3K/Akt/eNOS pathway, indicating a promising strategy against atherosclerosis.
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Affiliation(s)
- Lei Chen
- Department of Critical Care Medicine, Gansu Provincial Hospital of TCM, No. 418, Guazhou Road, Qilihe District, Lanzhou City, 730050, Gansu, People's Republic of China.
| | - Lijun Qin
- Department of Cardiology, Lanzhou University Second Hospital, Lanzhou, 730030, Gansu, People's Republic of China
| | - Xin Liu
- Department of Rheumatic Osteopathology, Gansu Provincial Hospital of TCM, Lanzhou, 730050, Gansu, People's Republic of China
| | - Xiangyun Meng
- Central Laboratory, Gansu Provincial Hospital of TCM, Lanzhou, 730050, Gansu, People's Republic of China
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9
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Ling WL, Ng YL, Wipat A, Lane DP, Gan SKE. The quantification of antibody elements and receptors subunit expression using qPCR: The design of VH, VL, CH, CL, FcR subunits primers for a more holistic view of the immune system. J Immunol Methods 2019; 476:112683. [PMID: 31682797 DOI: 10.1016/j.jim.2019.112683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/20/2019] [Accepted: 10/09/2019] [Indexed: 12/18/2022]
Abstract
The expression levels of immunoglobulin elements and their receptors are important markers for health and disease. Within the immunoglobulin locus, the constant regions and the variable region families are associated with certain pathologies, yet a holistic view of the interaction between the expressions of the multiple genes remain to be fully characterized. There is thus an important need to quantify antibody elements, their receptors and the receptor subunits in blood (PBMC cDNA) for both screening and detailed studies of such associations. Leveraging on qPCR, we designed primers for all Vκ1-6, VH1-7, Vλ1-11, nine CH isotypes, Cκ, Cκ, Cλ1 &3, FcεRI α,β, and γ subunits, all three FcγR and their subunits, and FcαR. Validating this on a volunteer PBMC cDNA, we report a qPCR primer set repertoire that can quantify the relative expression of all the above genes to the GAPDH housekeeping gene, with implications and uses in both clinical monitoring and research.
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Affiliation(s)
- Wei-Li Ling
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), Singapore; Newcastle Research and Innovation Institute (NewRIIS), Singapore.
| | - Yuen-Ling Ng
- Newcastle Research and Innovation Institute (NewRIIS), Singapore.
| | - Anil Wipat
- School of Computing, Newcastle University, UK.
| | - David Philip Lane
- p53 Laboratory, Agency for Science, Technology and Research (A*STAR), Singapore.
| | - Samuel Ken-En Gan
- Bioinformatics Institute, Agency for Science, Technology and Research (A*STAR), Singapore; p53 Laboratory, Agency for Science, Technology and Research (A*STAR), Singapore.
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10
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Xu L, Zhang L, Wang Z, Li C, Li S, Li L, Fan Q, Zheng L. Melatonin Suppresses Estrogen Deficiency-Induced Osteoporosis and Promotes Osteoblastogenesis by Inactivating the NLRP3 Inflammasome. Calcif Tissue Int 2018; 103:400-410. [PMID: 29804160 DOI: 10.1007/s00223-018-0428-y] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 04/30/2018] [Indexed: 01/08/2023]
Abstract
Postmenopausal osteoporosis induced by estrogen deficiency causes inadequate new bone formation and affects millions of women worldwide. Melatonin can improve bone mineral density at the femoral neck in postmenopausal women with osteopenia. This study aimed to investigate the mechanism of melatonin in estrogen deficiency-induced osteoporosis by focusing on osteoblast differentiation. 12-week-old female C57BL/6J mice were ovariectomized (OVX) and intraperitoneally injected with 10 or 50 mg/kg of melatonin for 8 weeks. Micro-computerized tomography scanning demonstrated that melatonin alleviated OVX-induced bone loss in a dose-dependent manner. Serum levels of ALP and osteocalcin (OCN) were further increased, whereas tartrate-resistant acid phosphatase level was decreased by melatonin in OVX-treated mice. Melatonin promoted osteoblast differentiation in primary bone marrow mesenchymal stem cells from OVX mice. It also inhibited activation of NLRP3 inflammasome in femoral bone protein and in induced osteoblasts stimulated by OVX. Knockdown of NLRP3 attenuated OVX-induced repression of osteogenic differentiation. The NLRP3 inflammasome activator monosodium urate partly abrogated the effect of melatonin on the expression of osteoblastogenic markers, including Runx2 and OCN. Additionally, the results showed that melatonin suppressed NLRP3 inflammasome activation by regulating Wnt/β-catenin signaling, which was confirmed by the Wnt/β-catenin inhibitor recombinant DKK1. These results indicated that melatonin ameliorates estrogen deficiency-induced osteoporosis and impaired osteogenic differentiation potential by suppressing activation of the NLRP3 inflammasome via mediating the Wnt/β-catenin pathway.
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Affiliation(s)
- Lijun Xu
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Lixia Zhang
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China.
| | - Zhifang Wang
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Chong Li
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Shan Li
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Li Li
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Qianying Fan
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
| | - Lili Zheng
- Department of Endocrinology, The First Affiliated Hospital of Zhengzhou University, Jianshe Road No.1, Erqi District, Zhengzhou, 450052, China
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11
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Weinstein JR, Quan Y, Hanson JF, Colonna L, Iorga M, Honda SI, Shibuya K, Shibuya A, Elkon KB, Möller T. IgM-Dependent Phagocytosis in Microglia Is Mediated by Complement Receptor 3, Not Fcα/μ Receptor. THE JOURNAL OF IMMUNOLOGY 2015; 195:5309-17. [PMID: 26500348 DOI: 10.4049/jimmunol.1401195] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 09/29/2015] [Indexed: 12/11/2022]
Abstract
Microglia play an important role in receptor-mediated phagocytosis in the CNS. In brain abscess and other CNS infections, invading bacteria undergo opsonization with Igs or complement. Microglia recognize these opsonized pathogens by Fc or complement receptors triggering phagocytosis. In this study, we investigated the role of Fcα/μR, the less-studied receptor for IgM and IgA, in microglial phagocytosis. We showed that primary microglia, as well as N9 microglial cells, express Fcα/μR. We also showed that anti-Staphylococcus aureus IgM markedly increased the rate of microglial S. aureus phagocytosis. To unequivocally test the role of Fcα/μR in IgM-mediated phagocytosis, we performed experiments in microglia from Fcα/μR(-/-) mice. Surprisingly, we found that IgM-dependent phagocytosis of S. aureus was similar in microglia derived from wild-type or Fcα/μR(-/-) mice. We hypothesized that IgM-dependent activation of complement receptors might contribute to the IgM-mediated increase in phagocytosis. To test this, we used immunologic and genetic inactivation of complement receptor 3 components (CD11b and CD18) as well as C3. IgM-, but not IgG-mediated phagocytosis of S. aureus was reduced in wild-type microglia and macrophages following preincubation with an anti-CD11b blocking Ab. IgM-dependent phagocytosis of S. aureus was also reduced in microglia derived from CD18(-/-) and C3(-/-) mice. Taken together, our findings implicate complement receptor 3 and C3, but not Fcα/μR, in IgM-mediated phagocytosis of S. aureus by microglia.
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Affiliation(s)
- Jonathan R Weinstein
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA 98195;
| | - Yi Quan
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA 98195
| | - Josiah F Hanson
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA 98195
| | - Lucrezia Colonna
- Division of Rheumatology, Department of Medicine, School of Medicine, University of Washington, Seattle, WA 98195; and
| | - Michael Iorga
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA 98195
| | - Shin-ichiro Honda
- Department of Immunology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575, Japan
| | - Kazuko Shibuya
- Department of Immunology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575, Japan
| | - Akira Shibuya
- Department of Immunology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575, Japan
| | - Keith B Elkon
- Division of Rheumatology, Department of Medicine, School of Medicine, University of Washington, Seattle, WA 98195; and
| | - Thomas Möller
- Department of Neurology, School of Medicine, University of Washington, Seattle, WA 98195
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12
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Yuan M, Fu H, Ren L, Wang H, Guo W. Soluble CD40 ligand promotes macrophage foam cell formation in the etiology of atherosclerosis. Cardiology 2015; 131:1-12. [PMID: 25825037 DOI: 10.1159/000374105] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 01/08/2015] [Indexed: 11/19/2022]
Abstract
OBJECTIVE High levels of soluble CD40 ligand (sCD40L) in the circulation have been suggested as an important indicator of cardiovascular diseases such as atherosclerosis and acute coronary syndromes. In the present study, we explored the role of sCD40L in the formation of foam cells. METHODS Lipid deposition and foam cell formation was measured by high-performance liquid chromatography and Nile Red staining, respectively. Gene expressions were detected by quantitative real-time PCR and Western blot analysis. The interaction between CD40 and sCD40L were blocked by CD40 small interfering RNA or anti-CD40 antibody. RESULTS sCD40L significantly increased lipid deposition and foam cell formation associated with upregulation of scavenger receptor type A and CD36. Additionally, sCD40L increased adipocyte enhancer-binding protein 1 and cholesterol efflux, and activated NF-κB in macrophages. sCD40L promoted foam cell formation via CD40 ligation and disruption of the ligation between CD40 and CD40L either by small interfering RNA or by a blocking anti-CD40 antibody apparently inhibiting foam cell formation in response to sCD40L. CONCLUSION Our data suggests a novel insight into the role of sCD40L in foam cell formation during atherosclerosis, which further confirms the importance of sCD40L in atherosclerosis and as a target for the treatment of this disease.
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Affiliation(s)
- Ming Yuan
- Department of Cardiology, Xijing Hospital, Fourth Military Medical University, Xi'an, China
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13
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14
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Liu J, Ren Y, Kang L, Zhang L. Oxidized low-density lipoprotein increases the proliferation and migration of human coronary artery smooth muscle cells through the upregulation of osteopontin. Int J Mol Med 2014; 33:1341-7. [PMID: 24590381 DOI: 10.3892/ijmm.2014.1681] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 02/21/2014] [Indexed: 11/06/2022] Open
Abstract
Smooth muscle cell (SMC) proliferation and migration are known to play a critical role in the development of atherosclerosis. Oxidized low-density lipoprotein (oxLDL) is involved in the generation of atherosclerotic lesions. Recent studies have indicated that oxLDL is a well-established risk factor for atherosclerosis that induces vascular smooth muscle cell (VSMC) proliferation and migration; however, the exact mechanisms involved have not been fully elucidated. In this study, the proliferation of human coronary artery smooth muscle cells (HCASMCs) was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell migration was determined by Transwell assay. Osteopontin (OPN), matrix metaloproteinase-9 (MMP-9) and αvβ3 integrin expression were measured by mRNA and western blot analysis. OPN and MMP-9 knockdown cells were established through transfection with OPN siRNA or MMP-9 siRNA, respectively. Our results revealed that oxLDL makredly promoted HCASMC proliferation and migration in a dose-dependent manner. Further experiments demonstrated that oxLDL upregulated the expression of OPN and oxLDL. Cell proliferation and migration were markedly reduced following the knockdown of the OPN gene in the HCASMCs. We then found that treatment with oxLDL induced a concentration-dependent increase in MMP-9 mRNA and protein levels in the HCASMCs. These effects were partially abrogated by silencing OPN expression or blocking the αvβ3 integrin pathway. Moreover, cells treated with MMP-9 siRNA or αvβ3 antibody showed lower proliferation and migration rates. This study provides direct in vitro evidence that the exposure of HCASMCs to oxLDL induces the activation of OPN, leading to higher protein levels of MMP-9, and to an increased proliferation and migration of HCASMCs.
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Affiliation(s)
- Jun Liu
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Yingang Ren
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Li Kang
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Lihua Zhang
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
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DONG WENPENG, WANG XIANYUE, BI SHENGHUI, PAN ZHIGUO, LIU SHENXI, YU HAO, LU HUA, LIN XI, WANG XIAOWU, MA TAO, ZHANG WEIDA. Inhibitory effects of resveratrol on foam cell formation are mediated through monocyte chemotactic protein-1 and lipid metabolism-related proteins. Int J Mol Med 2014; 33:1161-8. [DOI: 10.3892/ijmm.2014.1680] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 02/03/2014] [Indexed: 11/06/2022] Open
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16
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Zheng L, Zhang D, Zhang Y, Wen Y, Wang Y. mTOR signal transduction pathways contribute to TN-C FNIII A1 overexpression by mechanical stress in osteosarcoma cells. Mol Cells 2014; 37:118-25. [PMID: 24598996 PMCID: PMC3935624 DOI: 10.14348/molcells.2014.2247] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 01/13/2014] [Accepted: 01/14/2014] [Indexed: 11/27/2022] Open
Abstract
Osteosarcoma is the most common primary malignant bone tumor with a very poor prognosis. Treating osteosarcoma remains a challenge due to its high transitivity. Tenascin-C, with large molecular weight variants including different combinations of its alternative spliced FNIII repeats, is specifically over expressed in tumor tissues. This study examined the expression of Tenascin-C FNIIIA1 in osteosarcoma tissues, and estimated the effect of mechanical stimulation on A1 expression in MG-63 cells. Through immunohistochemical analysis, we found that the A1 protein was expressed at a higher level in osteosarcoma tissues than in adjacent normal tissues. By cell migration assay, we observed that there was a significant correlation between A1 expression and MG-63 cell migra-tion. The relation is that Tenascin-C FNIIIA1 can promote MG-63 cell migration. According to our further study into the effect of mechanical stimulation on A1 expression in MG-63 cells, the mRNA and protein levels of A1 were significantly up-regulated under mechanical stress with the mTOR molecule proving indispensable. Meanwhile, 4E-BP1 and S6K1 (downstream molecule of mTOR) are necessary for A1 normal expression in MG-63 cells whether or not mechanical stress has been encountered. We found that Tenascin-C FNIIIA1 is over-expressed in osteosar-coma tissues and can promote MG-63 cell migration. Furthermore, mechanical stress can facilitate MG-63 cell migration though facilitating A1 overexpression with the necessary molecules (mTOR, 4E-BP1 and S6K1). In con-clusion, high expression of A1 may promote the meta-stasis of osteosarcoma by facilitating MG-63 cell migration. Tenascin-C FNIIIA1 could be used as an indicator in metastatic osteosarcoma patients.
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Affiliation(s)
- Lianhe Zheng
- Department of Orthopaedic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, 710032, Shaanxi Province,
China
| | - Dianzhong Zhang
- Department of Orthopaedic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, 710032, Shaanxi Province,
China
| | - Yunfei Zhang
- Department of Orthopaedic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, 710032, Shaanxi Province,
China
| | - Yanhua Wen
- Department of Orthopaedic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, 710032, Shaanxi Province,
China
| | - Yucai Wang
- Department of Orthopaedic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi’an, 710032, Shaanxi Province,
China
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17
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Sharifov OF, Nayyar G, Ternovoy VV, Palgunachari MN, Garber DW, Anantharamaiah G, Gupta H. Comparison of anti-endotoxin activity of apoE and apoA mimetic derivatives of a model amphipathic peptide 18A. Innate Immun 2013; 20:867-80. [PMID: 24323453 DOI: 10.1177/1753425913514621] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Endotoxemia is a major cause of chronic inflammation, and is an important pathogenic factor in the development of metabolic syndrome and atherosclerosis. Human apolipoprotein E (apoE) and apoA-I are protein components of high-density lipoprotein, which have strong anti-endotoxin activity. Here, we compared anti-endotoxin activity of Ac-hE18A-NH2 and 4F peptides, modified from model amphipathic helical 18A peptide, to mimic, respectively, apoE and apoA-I properties. Ac-hE18A-NH2, stronger than 4F, inhibited endotoxin activity and disaggregated Escherichia coli 055:B5 (wild smooth serotype). Ac-hE18A-NH2 and 4F inhibited endotoxin activity of E. coli 026:B6 (rough-like serotype) to a similar degree. This suggests that Ac-hE18A-NH2 as a dual-domain molecule might interact with both the lipid A and headgroup of smooth LPS, whereas 4F binds lipid A. In C57BL/6 mice, Ac-hE18A-NH2 was superior to 4F in inhibiting the inflammatory responses mediated by E. coli 055:B5, but not E. coli 026:B6. However, in THP-1 cells, isolated human primary leukocytes, and whole human blood, Ac-hE18A-NH2 reduced responses more strongly than 4F to both E. coli serotypes either when peptides were pre-incubated or co-incubated with LPS, indicating that Ac-hE18A-NH2 also has strong anti-inflammatory effects independent of endotoxin-neutralizing properties. In conclusion, Ac-hE18A-NH2 is more effective than 4F in inhibiting LPS-mediated inflammation, which opens prospective clinical applications for Ac-hE18A-NH2.
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Affiliation(s)
- Oleg F Sharifov
- Department of Medicine, University of Alabama at Birmingham, AL, USA
| | - Gaurav Nayyar
- Department of Medicine, University of Alabama at Birmingham, AL, USA
| | | | | | - David W Garber
- Department of Medicine, University of Alabama at Birmingham, AL, USA
| | - Gm Anantharamaiah
- Department of Medicine, University of Alabama at Birmingham, AL, USA Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, AL, USA
| | - Himanshu Gupta
- Department of Medicine, University of Alabama at Birmingham, AL, USA VA Medical Center, Birmingham, AL, USA
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18
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19
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Sharifov OF, Nayyar G, Ternovoy VV, Mishra VK, Litovsky SH, Palgunachari MN, Garber DW, Anantharamaiah GM, Gupta H. Cationic peptide mR18L with lipid lowering properties inhibits LPS-induced systemic and liver inflammation in rats. Biochem Biophys Res Commun 2013; 436:705-10. [PMID: 23791744 DOI: 10.1016/j.bbrc.2013.06.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 06/07/2013] [Indexed: 10/26/2022]
Abstract
The cationic single domain peptide mR18L has demonstrated lipid-lowering and anti-atherogenic properties in different dyslipidemic mouse models. Lipopolysaccharide (LPS)-mediated inflammation is considered as one of the potential triggers for atherosclerosis. Here, we evaluated anti-inflammatory effects of mR18L peptide against LPS-mediated inflammation. First, we tested the efficacy and tolerance of 1, 2.5 and 5mg/kg mR18L in normolipidemic rats stimulated with 5mg/kg LPS. LPS and then mR18L were injected in different intraperitoneal regions. By 2h post LPS, mR18L inhibited LPS-mediated plasma TNF-α elevation at all doses, with the effect being stronger for 2.5mg/kg (P<0.05 vs. 1mg/kg, non-significant vs. 5mg/kg). In a similar model, 2.5mg/kg mR18L reduced LPS-mediated inflammation in the liver, as assessed by microscopic examination of liver sections and measurements of iNOS expression in the liver tissue. In plasma, 2.5mg/kg mR18L decreased levels of TNF-α and IL-6, decreased endotoxin activity and enhanced HDL binding to LPS. In another similar experiment, mR18L administered 1h post LPS, prevented elevation of plasma triglycerides by 6h post LPS and increased plasma activity of anti-oxidant enzyme paraoxonase 1, along with noted trends in reducing plasma levels of endotoxin and IL-6. Surface plasmon resonance study revealed that mR18L readily binds LPS. We conclude that mR18L exerts anti-endotoxin activity at least in part due to direct LPS-binding and LPS-neutralizing effects. We suggest that anti-endotoxin activity of mR18L is an important anti-inflammatory property, which may increase anti-atherogenic potential of this promising orally active lipid-lowering peptide.
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Affiliation(s)
- Oleg F Sharifov
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35216, United States
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20
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Gu L, Bai W, Li S, Zhang Y, Han Y, Gu Y, Meng G, Xie L, Wang J, Xiao Y, Shan L, Zhou S, Wei L, Ferro A, Ji Y. Celastrol prevents atherosclerosis via inhibiting LOX-1 and oxidative stress. PLoS One 2013; 8:e65477. [PMID: 23799016 PMCID: PMC3684610 DOI: 10.1371/journal.pone.0065477] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 04/25/2013] [Indexed: 02/07/2023] Open
Abstract
Celastrol is a triterpenoid compound extracted from the Chinese herb Tripterygium wilfordii Hook F. Previous research has revealed its anti-oxidant, anti-inflammatory, anti-cancer and immunosuppressive properties. Here, we investigated whether celastrol inhibits oxidized low-density lipoprotein (oxLDL) induced oxidative stress in RAW 264.7 cells. In addition, the effect of celastrol on atherosclerosis in vivo was assessed in apolipoprotein E knockout (apoE−/−) mouse fed a high-fat/high-cholesterol diet (HFC). We found that celastrol significantly attenuated oxLDL-induced excessive expression of lectin-like oxidized low density lipoprotein receptor-1(LOX-1) and generation of reactive oxygen species (ROS) in cultured RAW264.7 macrophages. Celastrol also decreased IκB phosphorylation and degradation and reduced production of inducible nitric oxide synthase (iNOS), nitric oxide (NO) and proinflammatory cytokines such as tumor necrosis factor (TNF)-α and IL-6. Celastrol reduced atherosclerotic plaque size in apoE−/− mice. The expression of LOX-1 within the atherosclerotic lesions and generation of superoxide in mouse aorta were also significantly reduced by celastrol while the lipid profile was not improved. In conclusion, our results show that celastrol inhibits atherosclerotic plaque developing in apoE−/− mice via inhibiting LOX-1 and oxidative stress.
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Affiliation(s)
- Lei Gu
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Wenli Bai
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Sha Li
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Yuqing Zhang
- Department of Cardiology, the Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, China
| | - Yi Han
- Department of Geriatrics, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yue Gu
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Guoliang Meng
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Liping Xie
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Jing Wang
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Yujiao Xiao
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Liyang Shan
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
| | - Suming Zhou
- Department of Cardiology, the Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, China
| | - Lei Wei
- Department of Cardiothoracic Surgery, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Albert Ferro
- Department of Clinical Pharmacology, Cardiovascular Division, King's College London, London, United Kingdom
| | - Yong Ji
- State Key Laboratory of Reproductive Medicine, Laboratory of Cardiovascular Disease and Molecular Intervention, Atherosclerosis Research Centre, Nanjing Medical University, Nanjing, China
- * E-mail:
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Yang X, Zhao Q, Zhu L, Zhang W. The three complementarity-determining region-like loops in the second extracellular domain of human Fc alpha/mu receptor contribute to its binding of IgA and IgM. Immunobiology 2013. [DOI: 10.1016/j.imbio.2012.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Wang J, Si Y, Wu C, Sun L, Ma Y, Ge A, Li B. Lipopolysaccharide promotes lipid accumulation in human adventitial fibroblasts via TLR4-NF-κB pathway. Lipids Health Dis 2012; 11:139. [PMID: 23072373 PMCID: PMC3485618 DOI: 10.1186/1476-511x-11-139] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 09/30/2012] [Indexed: 12/23/2022] Open
Abstract
Background Atherosclerosis is a chronic degenerative disease of the arteries and is thought to be one of the most common causes of death globally. In recent years, the functions of adventitial fibroblasts in the development of atherosclerosis and tissue repair have gained increased interests. LPS can increase the morbidity and mortality of atherosclerosis-associated cardiovascular disease. Although LPS increases neointimal via TLR4 activation has been reported, how LPS augments atherogenesis through acting on adventitial fibroblasts is still unknown. Here we explored lipid deposition within adventitial fibroblasts mediated by lipopolysaccharide (LPS) to imitate inflammatory conditions. Results In our study, LPS enhanced lipid deposition by the up-regulated expression of adipose differentiation-related protein (ADRP) as the silencing of ADRP abrogated lipid deposition in LPS-activated adventitial fibroblasts. In addition, pre-treatment with anti-Toll-like receptor 4 (TLR4) antibody diminished the LPS-induced lipid deposition and ADRP expression. Moreover, LPS induced translocation of nuclear factor-κB (NF-κB), which could markedly up-regulate lipid deposition as pre-treatment with the NF-κB inhibitor, PDTC, significantly reduced lipid droplets. In addition, the lowering lipid accumulation was accompanied with the decreased ADRP expression. Furthermore, LPS-induced adventitial fibroblasts secreted more monocyte chemoattractant protein (MCP-1), compared with transforming growth factor-β1 (TGF-β1). Conclusions Taken together, these results suggest that LPS promotes lipid accumulation via the up-regulation of ADRP expression through TLR4 activated downstream of NF-κB in adventitial fibroblasts. Increased levels of MCP-1 released from LPS-activated adventitial fibroblasts and lipid accumulation may accelerate monocytes recruitment and lipid-laden macrophage foam cells formation. Here, our study provides a new explanation as to how bacterial infection contributes to the pathological process of atherosclerosis.
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Affiliation(s)
- Jun Wang
- Department of Neurosurgery, the General Hospital of PLA, Beijing, 100853, China
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23
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Liu R, He Y, Li B, Liu J, Ren Y, Han W, Wang X, Zhang L. Tenascin-C produced by oxidized LDL-stimulated macrophages increases foam cell formation through Toll-like receptor-4. Mol Cells 2012; 34:35-41. [PMID: 22699754 PMCID: PMC3887780 DOI: 10.1007/s10059-012-0054-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 05/02/2012] [Accepted: 05/10/2012] [Indexed: 10/28/2022] Open
Abstract
Atherosclerosis is a chronic inflammatory disease in which both innate and adaptive immunity are involved. Although there have been major advances in the involvement of toll-like receptor 4 (TLR4) and CD36 in the initiation and development of this disease, detailed mechanisms remain unknown. Here, we show that tenascin-C (TN-C) can stimulate foam cell formation and this can be inhibited by a TLR4-blocking antibody or CD36 gene silencing. Our results identify TN-C-TLR4 activation as a common molecular mechanism in oxLDL-stimulated foam cell formation and atherosclerosis. In addition, CD36 is the major scavenger receptor responsible for the TN-C-mediated foam cell formation. Taken together, we have identified that TNC produced by oxLDL-stimulated macrophages increases foam cell formation through TLR4 and scavenger receptor CD36.
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Affiliation(s)
- Rui Liu
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Yong He
- Department of Cardiology, Tangdu Hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Bo Li
- Department of Cardiology, Tangdu Hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Jun Liu
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Yingang Ren
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Wei Han
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Xing Wang
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
| | - Lihua Zhang
- Department of Geriatrics, Tangdu hospital, The Fourth Military Medical University, Xi’an,
P.R. China
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Lipopolysaccharide-induced proliferation of the vasa vasorum in a rabbit model of atherosclerosis as evaluated by contrast-enhanced ultrasound imaging and histology. Inflammation 2012; 35:1530-7. [PMID: 22538510 DOI: 10.1007/s10753-012-9468-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Whether lipopolysaccharide (LPS) can promote vasa vasorum (VV) proliferation for atherosclerosis in vivo is unclear. Eighteen rabbits with atherosclerosis were randomly assigned into one of three groups of six. Group A received biweekly injections of 10 mL saline after 2 weeks of balloon injury. Groups B and C received biweekly intravenous injections of 3.0 μg LPS in 10 mL saline at weeks 10 and 4, respectively, until study termination. LPS significantly increased the levels of triglycerides and C-reactive protein and decreased the level of high-density lipoprotein cholesterol. Group C had significant larger plaques and more macrophages than group A (p = 0.01 and p < 0.001, respectively). Contrast enhancement ultrasound imaging and histological detection demonstrated that plaques in group C had a significantly higher VV density than that in group A (p = 0.009 and p = 0.002, respectively). In summary, VV proliferation for plaque destabilization can be accelerated by LPS-induced systemic inflammation and changes in lipid profiles.
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Grönwall C, Vas J, Silverman GJ. Protective Roles of Natural IgM Antibodies. Front Immunol 2012; 3:66. [PMID: 22566947 PMCID: PMC3341951 DOI: 10.3389/fimmu.2012.00066] [Citation(s) in RCA: 241] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 03/16/2012] [Indexed: 12/16/2022] Open
Abstract
Antibodies are a vital part of the armamentarium of the adaptive immune system for the fine-tuning of the recognition and response to foreign threats. However, in health there are some types of antibodies that instead recognize self-antigens and these contribute to the enhancement of primitive innate functions. This repertoire of natural IgM antibodies is postulated to have been selected during immune evolution for their contributions to critical immunoregulatory and housekeeping properties. The clearance of dying cells is one of the most essential responsibilities of the immune system, which is required to prevent uncontrolled inflammation and autoimmunity. In the murine immune system, natural IgM antibodies that recognize apoptotic cells have been shown to enhance the phagocytic clearance of dead and dying cells and to suppress innate immune signaling pathways. In the mouse, natural IgM are often the products of B-1 cell clones that arise during immune development without an absolute requirement for exogenous antigenic stimulation. In patients with systemic lupus erythematosus, IgM autoantibodies, which bind to neo-epitopes on apoptotic cells, have been demonstrated to be present at significantly higher levels in patients with lower disease activity and with less severe organ damage. While certain specificities of IgM autoantibodies correlate with protection from lupus renal disease, others may convey protective properties from lupus-associated atherosclerotic cardiovascular disease. New and unexpected insights into the functional roles of IgM antibodies are still emerging, especially regarding the functions of natural antibodies. Herein, we review recent progress in our understanding of the potential roles of natural IgM autoantibodies in the regulation of immune homeostasis and for protection from autoimmune and inflammatory diseases.
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Xu R, Feng X, Xie X, Zhang J, Wu D, Xu L. HIV-1 Tat protein increases the permeability of brain endothelial cells by both inhibiting occludin expression and cleaving occludin via matrix metalloproteinase-9. Brain Res 2011; 1436:13-9. [PMID: 22197032 DOI: 10.1016/j.brainres.2011.11.052] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 11/22/2011] [Accepted: 11/28/2011] [Indexed: 02/01/2023]
Abstract
Brain homeostasis is maintained by the blood-brain barrier (BBB), which prevents the entrance of circulating molecules and immune cells into the central nervous system. The BBB is formed by specialized brain endothelial cells that are connected by tight junctions (TJ). Previous studies have proven that the Tat protein of human immunodeficiency virus type 1 (HIV-1) alters TJ protein expression. However, the mechanisms by which the alterations occur have not been characterized in detail. In this study, primary human brain microvascular endothelial cells (HBMEC) were exposed to recombinant HIV-1 Tat protein, and the effects on occludin were observed. Tat treatment decreased occludin mRNA and protein levels. This effect was partially abrogated by addition of the RhoA inhibitor C3 exoenzyme and the p160-Rho-associated coiled kinase (ROCK) inhibitor Y-27632. Meanwhile, Tat also induced MMP-9 expression. RNA interference targeting MMP-9 reduced both the paracellular permeability of Tat-treated HBMEC and the concentration of soluble occludin in supernatants from the cells. Taken together, these results show that the HIV-1 Tat protein disrupts BBB integrity, at least in part by decreasing the production of occludin.
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Affiliation(s)
- Ruifen Xu
- Key Laboratory of Biomedical Information Engineering of Education Ministry, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
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Jang YJ, Joo HJ, Yang JI, Seo CW, Chung KY, Lanza GM, Zhang H. A human monoclonal antibody Fabreactive to oxidized LDL and carbamylated LDL recognizes human and mouse atherosclerotic lesions. Anim Cells Syst (Seoul) 2011. [DOI: 10.1080/19768354.2011.603747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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28
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PPARγ agonist rosiglitazone ameliorates LPS-induced inflammation in vascular smooth muscle cells via the TLR4/TRIF/IRF3/IP-10 signaling pathway. Cytokine 2011; 55:409-19. [DOI: 10.1016/j.cyto.2011.05.020] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 05/18/2011] [Accepted: 05/26/2011] [Indexed: 02/06/2023]
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29
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Yoo EM, Trinh KR, Lim H, Wims LA, Morrison SL. Characterization of IgA and IgM binding and internalization by surface-expressed human Fcα/μ receptor. Mol Immunol 2011; 48:1818-26. [DOI: 10.1016/j.molimm.2011.05.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 05/09/2011] [Indexed: 10/18/2022]
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30
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Raveendran VV, Tan X, Sweeney ME, Levant B, Slusser J, Stechschulte DJ, Dileepan KN. Lipopolysaccharide induces H1 receptor expression and enhances histamine responsiveness in human coronary artery endothelial cells. Immunology 2011; 132:578-88. [PMID: 21255012 DOI: 10.1111/j.1365-2567.2010.03403.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Summary Histamine is a well-recognized modulator of vascular inflammation. We have shown that histamine, acting via H1 receptors (H1R), synergizes lipopolysaccharide (LPS)-induced production of prostaglandin I(2) (PGI(2)), PGE(2) and interleukin-6 (IL-6) by endothelial cells. The synergy between histamine and LPS was partly attributed to histamine -induced expression of Toll-like receptor 4 (TLR4). In this study, we examined whether LPS stimulates the H1R expression in human coronary artery endothelial cells (HCAEC) with resultant enhancement of histamine responsiveness. Incubation of HCAEC with LPS (10-1000 ng/ml) resulted in two-fold to fourfold increases in H1R mRNA expression in a time-dependent and concentration-dependent fashion. In contrast, LPS treatment did not affect H2R mRNA expression. The LPS-induced H1R mRNA expression peaked by 4 hr after LPS treatment and remained elevated above the basal level for 20-24 hr. Flow cytometric and Western blot analyses revealed increased expression of H1R protein in LPS-treated cells. The specific binding of [(3)H]pyrilamine to H1R in membrane proteins from LPS-treated HCAEC was threefold higher than the untreated cells. The LPS-induced H1R expression was mediated through TLR4 as gene silencing by TLR4-siRNA and treatment with a TLR4 antagonist inhibited the LPS effect. When HCAEC were pre-treated with LPS for 24 hr, washed and challenged with histamine, 17-, 10- and 15-fold increases in PGI(2), PGE(2) and IL-6 production, respectively, were noted. Histamine-induced enhancement of the synthesis of PGI(2), PGE(2) and IL-6 by LPS-primed HCAEC was completely blocked by an H1R antagonist. The results demonstrate that LPS, through TLR4 activation, up-regulates the expression and function of H1R and amplifies histamine-induced inflammatory responses in HCAEC.
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Affiliation(s)
- Vineesh V Raveendran
- Division of Allergy, Clinical Immunology and Rheumatology, Department of Medicine, University of Kansas Medical Center, Kansas City, KS 66160, USA
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31
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Abstract
PURPOSE OF REVIEW The differentiation of macrophages into lipid-laden foam cells is central to the development of atherosclerosis. Traditionally, it has been assumed that the uptake of oxidized low-density lipoprotein by macrophage scavenger receptors is largely responsible for this process. However, in light of recent evidence that these mechanisms may not play as large a role as previously thought, alternative mechanisms of foam cell formation are now being explored. RECENT FINDINGS The stimulation of Toll-like receptor (TLR) signalling by bacterial molecules has been shown to promote the accumulation of lipid in macrophages in the form of intracellular inclusions termed 'lipid bodies'. Interactions between TLR-signalling pathways and the liver-X receptor and peroxisome proliferator-activated receptor-γ signalling pathways modulate the formation of lipid bodies in macrophages and thereby cellular accumulation of cholesterol and triglyceride. These pathways appear to involve TLR-mediated regulation of lipid-binding proteins, cellular cholesterol sensors, lipid-body-associated proteins and secreted autocrine factors, but are independent of scavenger receptor or lipoprotein oxidation-dependent pathways. SUMMARY TLR stimulation promotes the accumulation of lipid bodies in macrophages and consequently foam cell formation. The pathways responsible for these processes may constitute novel therapeutic targets for atherosclerosis.
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Affiliation(s)
- Giovanna Nicolaou
- Department of Cardiovascular Sciences, Glenfield General Hospital, University of Leicester, Leicester, UK
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