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Xie Z, Jiang N, Lin M, He X, Li B, Dong Y, Chen S, Lv G. The Mechanisms of Polysaccharides from Tonic Chinese Herbal Medicine on the Enhancement Immune Function: A Review. Molecules 2023; 28:7355. [PMID: 37959774 PMCID: PMC10648855 DOI: 10.3390/molecules28217355] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/19/2023] [Accepted: 10/23/2023] [Indexed: 11/15/2023] Open
Abstract
Tonic Chinese herbal medicine is a type of traditional Chinese medicine, and its primary function is to restore the body's lost nutrients, improve activity levels, increase disease resistance, and alleviate physical exhaustion. The body's immunity can be strengthened by its polysaccharide components, which also have a potent immune-system-protecting effect. Several studies have demonstrated that tonic Chinese herbal medicine polysaccharides can improve the body's immune response to tumor cells, viruses, bacteria, and other harmful substances. However, the regulatory mechanisms by which various polysaccharides used in tonic Chinese herbal medicine enhance immune function vary. This study examines the regulatory effects of different tonic Chinese herbal medicine polysaccharides on immune organs, immune cells, and immune-related cytokines. It explores the immune response mechanism to understand the similarities and differences in the effects of tonic Chinese herbal medicine polysaccharides on immune function and to lay the foundation for the future development of tonic Chinese herbal medicine polysaccharide products.
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Affiliation(s)
- Zhiyi Xie
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Ninghua Jiang
- The Second Affiliated Hospital of Jiaxing University, Jiaxing 314000, China;
| | - Minqiu Lin
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Xinglishang He
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Bo Li
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Yingjie Dong
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Suhong Chen
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou 313200, China
- Zhejiang Provincial Key Laboratory of TCM for Innovative R & D and Digital Intelligent Manufacturing of TCM Great Health Products, Huzhou 313200, China
| | - Guiyuan Lv
- College of Pharmaceutical Science, Zhejiang Chinese Medical University, Hangzhou 310053, China
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2
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Guo W, Cui S, Tang X, Zhang Q, Zhao J, Mao B, Zhang H. Intestinal Microbiomics and Metabolomics Insights into the Hepatoprotective Effects of Lactobacillus paracasei CCFM1222 Against the Acute Liver Injury in Mice. Probiotics Antimicrob Proteins 2023; 15:1063-1077. [PMID: 36056292 DOI: 10.1007/s12602-022-09986-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2022] [Indexed: 11/25/2022]
Abstract
In recent years, acute liver injury (ALI) has received wide-range attention in the world due to its relatively high morbidity and mortality. This study aimed to explore the hepatoprotective effect of Lactobacillus paracasei CCFM1222 against lipopolysaccharide (LPS)-induced ALI mice and further elaborate its mechanism of action from the perspective of intestinal microbiomics and metabolomics. The results displayed that L. paracasei CCFM1222 pretreatment significantly decreased the serum ALT, and AST levels, inhibited the releases of hepatic TNF-α, IL-1β, and IL-6 levels, and activated the SOD, CAT, and GSH-Px activities in LPS-treated mice. The cecal short-chain fatty acid (SCFAs) levels were increased in LPS-treated mice with L. paracasei CCFM1222 pretreatment. In addition, L. paracasei CCFM1222 pretreatment remarkably shifted the intestinal microbiota composition, including the higher abundance of Faecalibaculum, Bifidobacterium, and lower abundance of the Prevotellaceae NK3B31 group, which is positively associated with the cecal propionic, butyric, valeric, isobutyric, and isovaleric acids. The metabolomics based on UPLC-QTOF/MS revealed that L. paracasei CCFM1222 pretreatment significantly regulated the composition of feces metabolites in LPS-treated mice, especially the potential biomarker-related butanoate metabolism, vitamin B6 metabolism, D-glutamine and D-glutamate metabolism, tryptophan metabolism, caffeine metabolism, arginine biosynthesis, arginine, and proline metabolism. Moreover, L. paracasei CCFM1222 pretreatment remarkably regulated the expression of gene-associated ALI (including Tlr4, Myd88, Nf-kβ, iNOS, Cox2, Iκ-Bα, Nrf2, and Sirt-1). In conclusion, these results suggest the possibility that L. paracasei CCFM1222 supplementation has beneficial effects on preventing the occurrence and development of ALI by inhibiting the inflammatory responses and altering intestinal microbiota composition and their metabolites.
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Affiliation(s)
- Weiling Guo
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
| | - Shumao Cui
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
| | - Xin Tang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
| | - Qiuxiang Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
| | - Bingyong Mao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China.
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China.
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, China
- School of Food Science and Technology, Jiangnan University, Lihu Avenue 1800, Wuxi, 214122, China
- National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, 214122, China
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3
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Kim BS. Critical role of TLR activation in viral replication, persistence, and pathogenicity of Theiler's virus. Front Immunol 2023; 14:1167972. [PMID: 37153539 PMCID: PMC10157096 DOI: 10.3389/fimmu.2023.1167972] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 04/11/2023] [Indexed: 05/09/2023] Open
Abstract
Theiler's murine encephalomyelitis virus (TMEV) establishes persistent viral infections in the central nervous system and induces chronic inflammatory demyelinating disease in susceptible mice. TMEV infects dendritic cells, macrophages, B cells, and glial cells. The state of TLR activation in the host plays a critical role in initial viral replication and persistence. The further activation of TLRs enhances viral replication and persistence, leading to the pathogenicity of TMEV-induced demyelinating disease. Various cytokines are produced via TLRs, and MDA-5 signals linked with NF-κB activation following TMEV infection. In turn, these signals further amplify TMEV replication and the persistence of virus-infected cells. The signals further elevate cytokine production, promoting the development of Th17 responses and preventing cellular apoptosis, which enables viral persistence. Excessive levels of cytokines, particularly IL-6 and IL-1β, facilitate the generation of pathogenic Th17 immune responses to viral antigens and autoantigens, leading to TMEV-induced demyelinating disease. These cytokines, together with TLR2 may prematurely generate functionally deficient CD25-FoxP3+ CD4+ T cells, which are subsequently converted to Th17 cells. Furthermore, IL-6 and IL-17 synergistically inhibit the apoptosis of virus-infected cells and the cytolytic function of CD8+ T lymphocytes, prolonging the survival of virus-infected cells. The inhibition of apoptosis leads to the persistent activation of NF-κB and TLRs, which continuously provides an environment of excessive cytokines and consequently promotes autoimmune responses. Persistent or repeated infections of other viruses such as COVID-19 may result in similar continuous TLR activation and cytokine production, leading to autoimmune diseases.
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4
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Excessive Innate Immunity Steers Pathogenic Adaptive Immunity in the Development of Theiler's Virus-Induced Demyelinating Disease. Int J Mol Sci 2021; 22:ijms22105254. [PMID: 34067536 PMCID: PMC8156427 DOI: 10.3390/ijms22105254] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/06/2021] [Accepted: 05/13/2021] [Indexed: 01/05/2023] Open
Abstract
Several virus-induced models were used to study the underlying mechanisms of multiple sclerosis (MS). The infection of susceptible mice with Theiler’s murine encephalomyelitis virus (TMEV) establishes persistent viral infections and induces chronic inflammatory demyelinating disease. In this review, the innate and adaptive immune responses to TMEV are discussed to better understand the pathogenic mechanisms of viral infections. Professional (dendritic cells (DCs), macrophages, and B cells) and non-professional (microglia, astrocytes, and oligodendrocytes) antigen-presenting cells (APCs) are the major cell populations permissive to viral infection and involved in cytokine production. The levels of viral loads and cytokine production in the APCs correspond to the degrees of susceptibility of the mice to the TMEV-induced demyelinating diseases. TMEV infection leads to the activation of cytokine production via TLRs and MDA-5 coupled with NF-κB activation, which is required for TMEV replication. These activation signals further amplify the cytokine production and viral loads, promote the differentiation of pathogenic Th17 responses, and prevent cellular apoptosis, enabling viral persistence. Among the many chemokines and cytokines induced after viral infection, IFN α/β plays an essential role in the downstream expression of costimulatory molecules in APCs. The excessive levels of cytokine production after viral infection facilitate the pathogenesis of TMEV-induced demyelinating disease. In particular, IL-6 and IL-1β play critical roles in the development of pathogenic Th17 responses to viral antigens and autoantigens. These cytokines, together with TLR2, may preferentially generate deficient FoxP3+CD25- regulatory cells converting to Th17. These cytokines also inhibit the apoptosis of TMEV-infected cells and cytolytic function of CD8+ T lymphocytes (CTLs) and prolong the survival of B cells reactive to viral and self-antigens, which preferentially stimulate Th17 responses.
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5
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Li T, Hai L, Liu B, Mao W, Liu K, Li Q, Guo Y, Jia Y, Bao H, Cao J. TLR2/4 promotes PGE 2 production to increase tissue damage in Escherichia coli-infected bovine endometrial explants via MyD88/p38 MAPK pathway. Theriogenology 2020; 152:129-138. [PMID: 32408026 DOI: 10.1016/j.theriogenology.2020.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 03/31/2020] [Accepted: 04/04/2020] [Indexed: 01/22/2023]
Abstract
Prostaglandin E2 (PGE2), a lipid mediator, is released by several cell types including endometrial cells and plays a central role in bacterial infection of the endometrium during inflammation. PGE2 production accumulated in Escherichia coli (E. coli) -infected bovine endometrial tissue, which increased E. coli-infected endometrial tissue damage. However, the mechanisms of PGE2 accumulation in the E. coli-infected endometrium during inflammation-associated endometrial tissue damage remain unclear. This study was conducted to investigate the role of Toll-like receptors (TLRs) 2 and 4 in increased PGE2 production in E. coli-infected endometrial tissue. E. coli and TLR2/4 agonists significantly induced cyclooxygenase-2 and microsomal prostaglandin E synthase-1 expression and PGE2 synthesis detected by RT-PCR, Western blot, and ELISA in the endometrial tissue. The expression and synthesis were dramatically decreased by TLR4, myeloid differentiation factor88 (MyD88), and p38 mitogen-activated protein kinase (MAPK) inhibitors in E. coli-infected endometrial tissue. These inhibitors also significantly decreased proinflammatory factor (interleukin-6 and tumor necrosis factor-α) and damage-associated molecular pattern (high mobility group box-1 and hyaluronan-binding protein-1) release and tissue damage measured by double-label immunofluorescence in E. coli-infected endometrial explants. Our work provides in vitro evidence that TLR2/4-MyD88/p38 MAPK promotes PGE2 synthesis and E. coli-infected endometrial tissue damage, which may be useful for improving PGE2-based therapies for endometritis.
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Affiliation(s)
- Tingting Li
- College of Veterinary Medicine, China Agricultural University, Beijing, China; Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Lili Hai
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Bo Liu
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Wei Mao
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Kun Liu
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Qianru Li
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Yuli Guo
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Yan Jia
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Haixia Bao
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China
| | - Jinshan Cao
- Key Laboratory of Clinical Diagnosis and Treatment Techniques of Animal Disease for Ministry of Agriculture, College of Veterinary Medicine, Inner Mongolia Agricultural University, Huhhot, China.
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6
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Kong Q, Li N, Cheng H, Zhang X, Cao X, Qi T, Dai L, Zhang Z, Chen X, Li C, Li Y, Xue B, Fang L, Liu L, Ding Z. HSPA12A Is a Novel Player in Nonalcoholic Steatohepatitis via Promoting Nuclear PKM2-Mediated M1 Macrophage Polarization. Diabetes 2019; 68:361-376. [PMID: 30455376 DOI: 10.2337/db18-0035] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 10/23/2018] [Indexed: 11/13/2022]
Abstract
Nonalcoholic steatohepatitis (NASH) is the most prevalent cause of chronic liver disease worldwide. Macrophage-mediated inflammation plays a critical role in NASH pathogenesis; however, optimum therapies for macrophage activation and NASH remain elusive. HSPA12A encodes a novel member of the HSP70 family. Here, we report that NASH patients showed increased hepatic HSPA12A expression and serum HSPA12A contents. Intriguingly, knockout of HSPA12A (Hspa12a-/- ) in mice attenuated high-fat diet (HFD)-induced hepatic steatosis and injury. HFD-induced macrophage polarization toward an M1 phenotype and inflammatory responses in the liver of Hspa12a-/- mice were also attenuated. Loss- and gain-of-function studies revealed that the de novo lipogenesis in hepatocytes was regulated by the paracrine effects of macrophage HSPA12A rather than by hepatocyte HSPA12A. In-depth molecular analysis revealed that HSPA12A interacted with the M2 isoform of pyruvate kinase (PKM2) in macrophages and increased its nuclear translocation, thereby promoting M1 polarization and secretion of proinflammatory M1 cytokines; this led, ultimately, to hepatocyte steatosis via paracrine effects. Taken together, these findings show that HSPA12A acts as a novel regulator of M1 macrophage polarization and NASH pathogenesis by increasing nuclear PKM2. Strategies that inhibit macrophage HSPA12A might be a potential therapeutic intervention for NASH.
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Affiliation(s)
- Qiuyue Kong
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Nan Li
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hao Cheng
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaojin Zhang
- Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xiaofei Cao
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Tao Qi
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Leyang Dai
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Zhihong Zhang
- Department of Pathology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xuan Chen
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Chuanfu Li
- Department of Surgery, East Tennessee State University, Johnson City, TN
| | - Yuehua Li
- Department of Pathophysiology, Nanjing Medical University, Nanjing, China
| | - Bin Xue
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine and School of Medicine, Nanjing University, Nanjing, China
| | - Lei Fang
- Medical School of Nanjing University, Nanjing, China
| | - Li Liu
- Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Zhengnian Ding
- Department of Anesthesiology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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7
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Yan G, Zhao H, Zhang Q, Zhou Y, Wu L, Lei J, Wang X, Zhang J, Zhang X, Zheng L, Du G, Xiao W, Tang B, Miao H, Li Y. A RIPK3-PGE 2 Circuit Mediates Myeloid-Derived Suppressor Cell-Potentiated Colorectal Carcinogenesis. Cancer Res 2018; 78:5586-5599. [PMID: 30012671 DOI: 10.1158/0008-5472.can-17-3962] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/09/2018] [Accepted: 07/10/2018] [Indexed: 11/16/2022]
Abstract
Receptor-interacting protein kinase 3 (RIPK3) is essential for mucosal repair in inflammatory bowel diseases (IBD) and colorectal cancer. However, its role in tumor immunity is unknown. Here, we report that decreased RIPK3 in colorectal cancer correlates with the accumulation of myeloid-derived suppressor cells (MDSC). Deficiency of RIPK3 boosted tumorigenesis via accumulation and immunosuppressive activity of MDSCs. Reduction of RIPK3 in MDSC and colorectal cancer cells elicited NFκB-transcribed COX-2, which catalyzed the synthesis of prostaglandin E2 (PGE2). PGE2 exacerbated the immunosuppressive activity of MDSCs and accelerated tumor growth. Moreover, PGE2 suppressed RIPK3 expression while enhancing expression of NFκB and COX-2 in MDSCs and colorectal cancer cells. Inhibition of COX-2 or PGE2 receptors reversed the immunosuppressive activity of MDSCs and dampened tumorigenesis. Patient databases also delineated the correlation of RIPK3 and COX-2 expression with colorectal cancer survival. Our findings demonstrate a novel signaling circuit by which RIPK3 and PGE2 regulate tumor immunity, providing potential ideas for immunotherapy against colorectal cancer.Significance: A novel signaling circuit involving RIPK3 and PGE2 enhances accumulation and immunosuppressive activity of MDSCs, implicating its potential as a therapeutic target in anticancer immunotherapy.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/19/5586/F1.large.jpg Cancer Res; 78(19); 5586-99. ©2018 AACR.
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Affiliation(s)
- Guifang Yan
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Huakan Zhao
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Qi Zhang
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Yu Zhou
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Lei Wu
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Juan Lei
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiang Wang
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Jiangang Zhang
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Xiao Zhang
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China.,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Lu Zheng
- Department of Hepatobiliary Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Guangsheng Du
- Department of General Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Weidong Xiao
- Department of General Surgery, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Bo Tang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Hongming Miao
- Department of Biochemistry and Molecular Biology, Third Military Medical University, Chongqing, China.
| | - Yongsheng Li
- Institute of Cancer, Xinqiao Hospital, Third Military Medical University, Chongqing, China. .,Clinical Medicine Research Center, Xinqiao Hospital, Third Military Medical University, Chongqing, China
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8
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Robichaux WG, Cheng X. Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development. Physiol Rev 2018; 98:919-1053. [PMID: 29537337 PMCID: PMC6050347 DOI: 10.1152/physrev.00025.2017] [Citation(s) in RCA: 131] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
This review focuses on one family of the known cAMP receptors, the exchange proteins directly activated by cAMP (EPACs), also known as the cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFs). Although EPAC proteins are fairly new additions to the growing list of cAMP effectors, and relatively "young" in the cAMP discovery timeline, the significance of an EPAC presence in different cell systems is extraordinary. The study of EPACs has considerably expanded the diversity and adaptive nature of cAMP signaling associated with numerous physiological and pathophysiological responses. This review comprehensively covers EPAC protein functions at the molecular, cellular, physiological, and pathophysiological levels; and in turn, the applications of employing EPAC-based biosensors as detection tools for dissecting cAMP signaling and the implications for targeting EPAC proteins for therapeutic development are also discussed.
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Affiliation(s)
- William G Robichaux
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
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9
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Hock BD, McKenzie JL, Keenan JI. Helicobacter pylori outer membrane vesicles inhibit human T cell responses via induction of monocyte COX-2 expression. Pathog Dis 2018; 75:3738186. [PMID: 28430970 DOI: 10.1093/femspd/ftx034] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 03/16/2017] [Indexed: 12/30/2022] Open
Abstract
The modulation of T cell responses by Helicobacter pylori is thought to potentiate both H. pylori persistence and development of gastric pathologies including cancer. Release of outer membrane vesicles (OMV) by H. pylori provides a potential vehicle for modulation of the immune system. Although OMV are thought to have T cell suppressive activity, this has not yet been demonstrated. Their suppressive activity was investigated in this study using the responses of peripheral blood mononuclear cells (PBMC) to T cell stimuli as a readout. We demonstrate that addition of OMV to PBMC significantly inhibits subsequent T cell proliferation in a cyclo-oxygenase-2 (COX-2)-dependent manner. Addition of OMV did not significantly modulate PBMC apoptosis, but induced strong expression of COX-2 by the monocytes present and significantly increased levels of PGE2 and IL-10. These effects were independent of vacuolating cytotoxin expression. Together, these findings demonstrate that OMV can suppress human T cell responses and that the predominant mechanism is not through a direct effect on the T cells but results from the induction of COX-2 expression in monocytes. This increased COX-2 activity may modulate not only H. pylori-directed immune responses but also wider immune responses.
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Affiliation(s)
- Barry D Hock
- Haematology Research Group, Christchurch Hospital and Department of Pathology, University of Otago, Christchurch 8140, New Zealand
| | - Judith L McKenzie
- Haematology Research Group, Christchurch Hospital and Department of Pathology, University of Otago, Christchurch 8140, New Zealand
| | - Jacqueline I Keenan
- Department of Surgery, University of Otago Christchurch, Christchurch 8140, New Zealand
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10
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Tian JJ, Lei CX, Ji H, Jin A. Role of cyclooxygenase-mediated metabolites in lipid metabolism and expression of some immune-related genes in juvenile grass carp (Ctenopharyngodon idellus) fed arachidonic acid. FISH PHYSIOLOGY AND BIOCHEMISTRY 2017; 43:703-717. [PMID: 28012026 DOI: 10.1007/s10695-016-0326-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 12/11/2016] [Indexed: 06/06/2023]
Abstract
Cyclooxygenase (COX) catalyzes the conversion of arachidonic acid (ARA) to prostaglandins, and COX-mediated metabolites play important roles in the regulation of lipid metabolism and immunity in mammals. However, such roles of COX in fish remain largely unknown. In this study, we designed three semi-purified diets, namely ARA-free (control), ARA, and ARA + acetylsalicylic acid (ASA; a COX inhibitor), and used them to feed grass carp (27.65 ± 3.05 g) for 8 weeks. The results showed that dietary ARA significantly increased the amount of ARA in the hepatopancreas, muscle, and kidney (P < 0.05), whereas this increase was reduced by dietary ASA. The hepatopancreatic prostaglandin E2 content increased in the ARA group, and this increase was inhibited by ASA (P < 0.05). ARA decreased the lipid content in the hepatopancreas, whereas ASA recovered lipid content to a significant level (P < 0.05). ARA significantly decreased the messenger RNA (mRNA) expression levels of fatty acid synthase and stearoyl-CoA desaturase in the hepatopancreas (P < 0.05). However, ASA did not rescue the mRNA expression of these genes (P > 0.05). Interestingly, ARA significantly enhanced the level of peroxisome proliferator-activated receptor α gene expression, and this increase was attenuated by ASA (P < 0.05). Finally, ARA significantly enhanced the mRNA expression of myeloid differentiation factor 88 (MyD88) in the kidney, and ASA attenuated the expression of toll-like receptor 22 and MyD88 (P < 0.05). In conclusion, our findings suggest that COX metabolites play important roles in the inhibition of lipid accumulation in the hepatopancreas of grass carp fed with ARA and that regulation of gene expression promotes lipid catabolism rather than lipogenic activities. Additionally, these eicosanoids might participate in the upregulation of immunity-related genes in the kidney.
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Affiliation(s)
- Jing-Jing Tian
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, People's Republic of China
| | - Cai-Xia Lei
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, People's Republic of China
| | - Hong Ji
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, People's Republic of China.
| | - Ai Jin
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, People's Republic of China
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11
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Kim SJ, Jin YH, Kim BS. Prostaglandin E2 produced following infection with Theiler's virus promotes the pathogenesis of demyelinating disease. PLoS One 2017; 12:e0176406. [PMID: 28445497 PMCID: PMC5406002 DOI: 10.1371/journal.pone.0176406] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 04/09/2017] [Indexed: 12/11/2022] Open
Abstract
Infection of various cells with Theiler’s murine encephalomyelitis virus (TMEV) activates the TLR- and melanoma differentiation-associated gene 5 (MDA5)-dependent pathways, resulting in the production of IL-1β via the activation of caspase-1 upon assembly of the node-like receptor protein 3 (NLRP3) inflammasome. The role of IL-1β in the pathogenesis of TMEV-induced demyelinating disease was previously investigated. However, the signaling effects of prostaglandin E2 (PGE2) downstream of the NLRP3 inflammasome on the immune responses to viral determinants and the pathogenesis of demyelinating disease are unknown. In this study, we investigated the levels of intermediate molecules leading to PGE2 signaling and the effects of blocking PGE2 signaling on the immune response to TMEV infection, viral persistence and the development of demyelinating disease. We demonstrate here that TMEV infection activates the NLRP3 inflammasome and PGE2 signaling much more vigorously in dendritic cells (DCs) and CD11b+ cells from susceptible SJL mice than in cells from resistant B6 mice. Inhibition of virus-induced PGE2 signaling using AH23848 resulted in decreased pathogenesis of demyelinating disease and viral loads in the central nervous system (CNS). In addition, AH23848 treatment caused the elevation of protective early IFN-γ-producing CD4+ and CD8+ T cell responses. Because the levels of IFN-β were lower in AH23848-treated mice but the level of IL-6 was similar, over-production of pathogenic IFN-β was modulated and the generation of IFN-γ-producing T cell responses was enhanced by the inhibition of PGE2 signaling. These results strongly suggest that excessive activation of the NLRP3 inflammasome and downstream PGE2 signaling contribute to the pathogenesis of TMEV-induced demyelinating disease.
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Affiliation(s)
- Seung Jae Kim
- Department of Microbiology-Immunology, Northwestern University Medical School, Chicago, Illinois
| | - Young-Hee Jin
- Department of Microbiology-Immunology, Northwestern University Medical School, Chicago, Illinois
| | - Byung S. Kim
- Department of Microbiology-Immunology, Northwestern University Medical School, Chicago, Illinois
- * E-mail:
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12
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Buzzo CDL, Medina T, Branco LM, Lage SL, Ferreira LCDS, Amarante-Mendes GP, Hottiger MO, De Carvalho DD, Bortoluci KR. Epigenetic regulation of nitric oxide synthase 2, inducible (Nos2) by NLRC4 inflammasomes involves PARP1 cleavage. Sci Rep 2017; 7:41686. [PMID: 28150715 PMCID: PMC5288713 DOI: 10.1038/srep41686] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/21/2016] [Indexed: 12/11/2022] Open
Abstract
Nitric oxide synthase 2, inducible (Nos2) expression is necessary for the microbicidal activity of macrophages. However, NOS2 over-activation causes multiple inflammatory disorders, suggesting a tight gene regulation is necessary. Using cytosolic flagellin as a model for inflammasome-dependent NOS2 activation, we discovered a surprising new role for NLRC4/caspase-1 axis in regulating chromatin accessibility of the Nos2 promoter. We found that activation of two independent mechanisms is necessary for NOS2 expression by cytosolic flagellin: caspase-1 and NF-κB activation. NF-κB activation was necessary, but not sufficient, for NOS2 expression. Conversely, caspase-1 was necessary for NOS2 expression, but dispensable for NF-κB activation, indicating that this protease acts downstream NF-κB activation. We demonstrated that epigenetic regulation of Nos2 by caspase-1 involves cleavage of the chromatin regulator PARP1 (also known as ARTD1) and chromatin accessibility of the NF-κB binding sites located at the Nos2 promoter. Remarkably, caspase-1-mediated Nos2 transcription and NO production contribute to the resistance of macrophages to Salmonella typhimurium infection. Our results uncover the molecular mechanism behind the constricted regulation of Nos2 expression and open new therapeutic opportunities based on epigenetic activities of caspase-1 against infectious and inflammatory diseases.
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Affiliation(s)
- Carina de Lima Buzzo
- Centro de Terapia Celular e Molecular (CTC-Mol) e Departamento de Ciências Biológicas - Universidade Federal de São Paulo, São Paulo, Brazil.,Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Tiago Medina
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, M5G 2M9, Canada
| | - Laura M Branco
- Centro de Terapia Celular e Molecular (CTC-Mol) e Departamento de Ciências Biológicas - Universidade Federal de São Paulo, São Paulo, Brazil.,Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo and Instituto de Investigação em Imunologia, Instituto Nacional de Ciência e Tecnologia (INCT-iii), Brazil
| | - Silvia L Lage
- Centro de Terapia Celular e Molecular (CTC-Mol) e Departamento de Ciências Biológicas - Universidade Federal de São Paulo, São Paulo, Brazil.,Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo and Instituto de Investigação em Imunologia, Instituto Nacional de Ciência e Tecnologia (INCT-iii), Brazil
| | | | - Gustavo P Amarante-Mendes
- Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo and Instituto de Investigação em Imunologia, Instituto Nacional de Ciência e Tecnologia (INCT-iii), Brazil
| | - Michael O Hottiger
- Department of Molecular Mechanisms of Disease, University of Zurich, Zurich, Switzerland
| | - Daniel D De Carvalho
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON, M5G 2M9, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 2M9, Canada
| | - Karina R Bortoluci
- Centro de Terapia Celular e Molecular (CTC-Mol) e Departamento de Ciências Biológicas - Universidade Federal de São Paulo, São Paulo, Brazil
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13
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Speth JM, Bourdonnay E, Penke LRK, Mancuso P, Moore BB, Weinberg JB, Peters-Golden M. Alveolar Epithelial Cell-Derived Prostaglandin E2 Serves as a Request Signal for Macrophage Secretion of Suppressor of Cytokine Signaling 3 during Innate Inflammation. THE JOURNAL OF IMMUNOLOGY 2016; 196:5112-20. [PMID: 27183597 DOI: 10.4049/jimmunol.1502153] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 04/15/2016] [Indexed: 01/22/2023]
Abstract
Preservation of gas exchange mandates that the pulmonary alveolar surface restrain unnecessarily harmful inflammatory responses to the many challenges to which it is exposed. These responses reflect the cross-talk between alveolar epithelial cells (AECs) and resident alveolar macrophages (AMs). We recently determined that AMs can secrete suppressor of cytokine signaling (SOCS) proteins within microparticles. Uptake of these SOCS-containing vesicles by epithelial cells inhibits cytokine-induced STAT activation. However, the ability of epithelial cells to direct AM release of SOCS-containing vesicles in response to inflammatory insults has not been studied. In this study, we report that SOCS3 protein was elevated in bronchoalveolar lavage fluid of both virus- and bacteria-infected mice, as well as in an in vivo LPS model of acute inflammation. In vitro studies revealed that AEC-conditioned medium (AEC-CM) enhanced AM SOCS3 secretion above basal levels. Increased amounts of PGE2 were present in AEC-CM after LPS challenge, and both pharmacologic inhibition of PGE2 synthesis in AECs and neutralization of PGE2 in AEC-CM implicated this prostanoid as the major AEC-derived factor mediating enhanced AM SOCS3 secretion. Moreover, pharmacologic blockade of PGE2 synthesis or genetic deletion of a PGE2 synthase similarly attenuated the increase in bronchoalveolar lavage fluid SOCS3 noted in lungs of mice challenged with LPS in vivo. These results demonstrate a novel tunable form of cross-talk in which AECs use PGE2 as a signal to request SOCS3 from AMs to dampen their endogenous inflammatory responses during infection.
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Affiliation(s)
- Jennifer M Speth
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Emilie Bourdonnay
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Loka Raghu Kumar Penke
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Peter Mancuso
- Department of Nutritional Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109; Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Bethany B Moore
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109; Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI 48109; Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109; and
| | - Jason B Weinberg
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109; and Division of Infectious Diseases, Department of Pediatrics and Communicable Diseases, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Marc Peters-Golden
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109; Graduate Program in Immunology, University of Michigan Medical School, Ann Arbor, MI 48109;
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14
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de Punder K, Pruimboom L. Stress induces endotoxemia and low-grade inflammation by increasing barrier permeability. Front Immunol 2015; 6:223. [PMID: 26029209 PMCID: PMC4432792 DOI: 10.3389/fimmu.2015.00223] [Citation(s) in RCA: 165] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 04/24/2015] [Indexed: 12/17/2022] Open
Abstract
Chronic non-communicable diseases (NCDs) are the leading causes of work absence, disability, and mortality worldwide. Most of these diseases are associated with low-grade inflammation. Here, we hypothesize that stresses (defined as homeostatic disturbances) can induce low-grade inflammation by increasing the availability of water, sodium, and energy-rich substances to meet the increased metabolic demand induced by the stressor. One way of triggering low-grade inflammation is by increasing intestinal barrier permeability through activation of various components of the stress system. Although beneficial to meet the demands necessary during stress, increased intestinal barrier permeability also raises the possibility of the translocation of bacteria and their toxins across the intestinal lumen into the blood circulation. In combination with modern life-style factors, the increase in bacteria/bacterial toxin translocation arising from a more permeable intestinal wall causes a low-grade inflammatory state. We support this hypothesis with numerous studies finding associations with NCDs and markers of endotoxemia, suggesting that this process plays a pivotal and perhaps even a causal role in the development of low-grade inflammation and its related diseases.
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Affiliation(s)
- Karin de Punder
- Institute of Medical Psychology, Charité University Medicine , Berlin , Germany ; Natura Foundation , Numansdorp , Netherlands
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15
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Wang Z, Brandt S, Medeiros A, Wang S, Wu H, Dent A, Serezani CH. MicroRNA 21 is a homeostatic regulator of macrophage polarization and prevents prostaglandin E2-mediated M2 generation. PLoS One 2015; 10:e0115855. [PMID: 25706647 PMCID: PMC4338261 DOI: 10.1371/journal.pone.0115855] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 12/02/2014] [Indexed: 12/17/2022] Open
Abstract
Macrophages dictate both initiation and resolution of inflammation. During acute inflammation classically activated macrophages (M1) predominate, and during the resolution phase alternative macrophages (M2) are dominant. The molecular mechanisms involved in macrophage polarization are understudied. MicroRNAs are differentially expressed in M1 and M2 macrophages that influence macrophage polarization. We identified a role of miR-21 in macrophage polarization, and found that cross-talk between miR-21 and the lipid mediator prostaglandin E2 (PGE2) is a determining factor in macrophage polarization. miR-21 inhibition impairs expression of M2 signature genes but not M1 genes. PGE2 and its downstream effectors PKA and Epac inhibit miR-21 expression and enhance expression of M2 genes, and this effect is more pronounced in miR-21-/- cells. Among potential targets involved in macrophage polarization, we found that STAT3 and SOCS1 were enhanced in miR-21-/- cells and further enhanced by PGE2. We found that STAT3 was a direct target of miR-21 in macrophages. Silencing the STAT3 gene abolished PGE2-mediated expression of M2 genes in miR-21-/- macrophages. These data shed light on the molecular brakes involved in homeostatic macrophage polarization and suggest new therapeutic strategies to prevent inflammatory responses.
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Affiliation(s)
- Zhuo Wang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Stephanie Brandt
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Alexandra Medeiros
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista “Júlio de Mesquita Filho,” 14801–902 Araraquara, São Paulo, Brazil
| | - Soujuan Wang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Hao Wu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Alexander Dent
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - C. Henrique Serezani
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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16
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Zoccal KF, Bitencourt CDS, Paula-Silva FWG, Sorgi CA, de Castro Figueiredo Bordon K, Arantes EC, Faccioli LH. TLR2, TLR4 and CD14 recognize venom-associated molecular patterns from Tityus serrulatus to induce macrophage-derived inflammatory mediators. PLoS One 2014; 9:e88174. [PMID: 24516606 PMCID: PMC3917877 DOI: 10.1371/journal.pone.0088174] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 01/06/2014] [Indexed: 12/12/2022] Open
Abstract
Scorpion sting-induced human envenomation provokes an intense inflammatory reaction. However, the mechanisms behind the recognition of scorpion venom and the induction of mediator release in mammalian cells are unknown. We demonstrated that TLR2, TLR4 and CD14 receptors sense Tityus serrulatus venom (TsV) and its major component, toxin 1 (Ts1), to mediate cytokine and lipid mediator production. Additionally, we demonstrated that TsV induces TLR2- and TLR4/MyD88-dependent NF-κB activation and TLR4-dependent and TLR2/MyD88-independent c-Jun activation. Similar to TsV, Ts1 induces MyD88-dependent NF-κB phosphorylation via TLR2 and TLR4 receptors, while c-Jun activation is dependent on neither TLR2 nor TLR4/MyD88. Therefore, we propose the term venom-associated molecular pattern (VAMP) to refer to molecules that are introduced into the host by stings and are recognized by PRRs, resulting in inflammation.
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Affiliation(s)
- Karina Furlani Zoccal
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Claudia da Silva Bitencourt
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Francisco Wanderley Garcia Paula-Silva
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Carlos Artério Sorgi
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Karla de Castro Figueiredo Bordon
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Eliane Candiani Arantes
- Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Lúcia Helena Faccioli
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
- * E-mail:
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17
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Koga MM, Bizzarro B, Sá-Nunes A, Rios FJO, Jancar S. Activation of PAF-receptor induces regulatory dendritic cells through PGE2 and IL-10. Prostaglandins Leukot Essent Fatty Acids 2013; 89:319-26. [PMID: 24120121 DOI: 10.1016/j.plefa.2013.09.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 08/15/2013] [Accepted: 09/06/2013] [Indexed: 11/20/2022]
Abstract
Activation of the platelet-activating factor receptor (PAFR) in macrophages is associated with suppressor phenotype. Here, we investigated the PAFR in murine dendritic cells (DC). Bone marrow-derived dendritic cells (BALB/c) were cultured with GM-CSF and maturation was induced by LPS. The PAFR antagonists (WEB2086, WEB2170, PCA4248) and the prostaglandin (PG) synthesis inhibitors (indomethacin, nimesulide and NS-398) were added before LPS. Mature and immature DCs expressed PAFR. LPS increased MHCII, CD40, CD80, CD86, CCR7 and induced IL-10, IL-12, COX-2 and PGE2 expression. IL-10, COX-2 and PGE2 levels were reduced by PAFR antagonists and increased by cPAF. The IL-10 production was independent of PGs. Mature DCs induced antigen-specific lymphocyte proliferation. PAFR antagonists or PG-synthesis inhibitors significantly increased lymphocyte proliferation. It is proposed that PAF has a central role in regulatory DC differentiation through potentiation of IL-10 and PGE2 production.
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Affiliation(s)
- Marianna M Koga
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo 05508-900, SP, Brazil
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18
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Yin H, Zhou Y, Zhu M, Hou S, Li Z, Zhong H, Lu J, Meng T, Wang J, Xia L, Xu Y, Wu Y. Role of mitochondria in programmed cell death mediated by arachidonic acid-derived eicosanoids. Mitochondrion 2012; 13:209-24. [PMID: 23063711 DOI: 10.1016/j.mito.2012.10.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 09/24/2012] [Accepted: 10/02/2012] [Indexed: 01/28/2023]
Abstract
Arachidonic acid-derived eicosanoids from cyclooxygenases, lipoxygenases, and cytochrome P450 are important lipid mediators involved in numerous homeostatic and pathophysiological processes. Most eicosanoids act primarily on their respective cell surface G-protein coupled receptors to elicit downstream signaling in an autocrine and paracrine fashion. Emerging evidence indicates that these hormones are also critical in apoptosis in a cell/tissue specific manner. In this review, we summarize the formation of eicosanoids and their roles as mediators in apoptosis, specifically on the roles of mitochondria in mediating these events and the signaling pathways involved. The biological relevance of eicosanoid-mediated apoptosis is also discussed.
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Affiliation(s)
- Huiyong Yin
- Laboratory of Lipid Metabolism in Human Nutrition and Related Diseases, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
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19
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Kaul V, Bhattacharya D, Singh Y, Van Kaer L, Peters-Golden M, Bishai WR, Das G. An important role of prostanoid receptor EP2 in host resistance to Mycobacterium tuberculosis infection in mice. J Infect Dis 2012; 206:1816-25. [PMID: 23033144 DOI: 10.1093/infdis/jis609] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mycobacterium tuberculosis, the causative agent of tuberculosis, resides and replicates within susceptible hosts by inhibiting host antimicrobial mechanisms. Prostaglandin E(2) (PGE(2)), produced by M. tuberculosis-infected macrophages, exerts a variety of immunomodulatory functions via 4 receptors (EP1-EP4), each mediating distinct PGE(2) functions. Here, we show that M. tuberculosis infection selectively upregulates EP2 messenger RNA expression in CD4(+) T cells. We found that EP2 deficiency in mice increases susceptibility to M. tuberculosis infection, which correlated with reduced antigen-specific T-cell responses and increased levels of CD4(+)CD25(+)Foxp3(+) T-regulatory cells. These findings have revealed an important role for EP2 in host immune defense against tuberculosis. As a G protein-coupled receptor, EP2 could serve as a target for immunotherapy of tuberculosis.
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Affiliation(s)
- Vandana Kaul
- Immunology Group, International Center for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
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20
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Long-term leptin treatment exerts a pro-apoptotic effect on renal tubular cells via prostaglandin E2 augmentation. Eur J Pharmacol 2012; 689:65-71. [DOI: 10.1016/j.ejphar.2012.06.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 06/01/2012] [Accepted: 06/08/2012] [Indexed: 01/01/2023]
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21
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Singh-Jasuja H, Thiolat A, Ribon M, Boissier MC, Bessis N, Rammensee HG, Decker P. The mouse dendritic cell marker CD11c is down-regulated upon cell activation through Toll-like receptor triggering. Immunobiology 2012; 218:28-39. [PMID: 22445076 DOI: 10.1016/j.imbio.2012.01.021] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 12/22/2011] [Accepted: 01/27/2012] [Indexed: 02/06/2023]
Abstract
Dendritic cells (DC) play a key role in regulating immune responses and are the best professional antigen-presenting cells. Two major DC populations are defined in part according to cell surface CD11c expression levels. Unexpectedly, we observed that mouse DC strongly down-regulate the typical DC marker CD11c upon activation. To better characterize DC responses, we have analyzed CD11c expression on mouse and human myeloid DC after Toll-like receptor (TLR) triggering. Here we show that mouse bone marrow-derived DC (BMDC) as well as spleen DC down-regulate cell surface CD11c upon activation by TLR3/4/9 agonists. In all cases, full DC activation was reached, as determined by cytokine secretion, cell stimulation in mixed leukocyte reactions (MLR), and CD40/CD86/major histocompatibility complex (MHC) up-regulation. Interestingly, membrane CD11c down-regulation correlated with increased cytoplasmic pools of CD11c. In contrast to the up-regulation of CD40 and MHC class II molecules, lipopolysaccharide (LPS)-induced CD11c down-regulation was MyD88-dependent. Polyinosinic-polycytidylic acid (poly I:C), which does not signal through MyD88, also induced cell surface CD11c down-regulation. Notably, CD11c down-regulation was not observed upon activation of human DC, either through TLR-dependent or -independent cell activation. Thus, activated mouse DC may be transiently CD11c-negative in vivo, hampering the identification of those cells. On the other hand, cell surface CD11c down-regulation may serve as a new activation marker for mouse DC.
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Affiliation(s)
- Harpreet Singh-Jasuja
- Institute for Cell Biology, Department of Immunology, University of Tübingen, Tübingen, Germany
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22
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Liberman AC, Refojo D, Antunica-Noguerol M, Holsboer F, Arzt E. Underlying mechanisms of cAMP- and glucocorticoid-mediated inhibition of FasL expression in activation-induced cell death. Mol Immunol 2012; 50:220-35. [PMID: 22341864 DOI: 10.1016/j.molimm.2012.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Revised: 01/04/2012] [Accepted: 01/21/2012] [Indexed: 11/19/2022]
Abstract
Glucocorticoids (GCs) and cAMP-dependent signaling pathways exert diverse and relevant immune regulatory functions, including a tight control of T cell death and homeostasis. Both of these signaling molecules inhibit TCR-induced cell death and FasL expression, but the underlying mechanisms are still poorly understood. Therefore, to address this question, we performed a comprehensive screening of signaling pathways downstream of the TCR, in order to define which of them are targets of cAMP- and GC-mediated inhibition. We found that cAMP inhibited NF-κB and ERK pathways through a PKA-dependent mechanism, while Dexamethasone blocked TCR-induced NF-κB signaling. Although GCs and cAMP inhibited the induction of endogenous FasL mRNA expression triggered by TCR activation, they potentiated TCR-mediated induction of FasL promoter activity in transient transfection assays. However, when the same FasL promoter was stably transfected, the facilitatory effect of GCs and cAMP became inhibitory, thus resembling the effects on endogenous FasL mRNA expression. Hence, the endogenous chromatinization status known to occur in integrated or genomic vs. episomic DNA might be critical for proper regulation of FasL expression by cAMP and GCs. Our results suggest that the chromatinization status of the FasL promoter may function as a molecular switch, controlling cAMP and GC responsiveness and explaining why these agents inhibit FasL expression in T cells but induce FasL in other cell types.
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Affiliation(s)
- Ana C Liberman
- Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología y Biología Molecular y Celular, Universidad de Buenos Aires and IBioBA-CONICET, 1428 Buenos Aires, Argentina
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Serezani CH, Kane S, Medeiros AI, Cornett AM, Kim SH, Marques MM, Lee SP, Lewis C, Bourdonnay E, Ballinger MN, White ES, Peters-Golden M. PTEN directly activates the actin depolymerization factor cofilin-1 during PGE2-mediated inhibition of phagocytosis of fungi. Sci Signal 2012; 5:ra12. [PMID: 22317922 DOI: 10.1126/scisignal.2002448] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Macrophage ingestion of the yeast Candida albicans requires its recognition by multiple receptors and the activation of diverse signaling programs. Synthesis of the lipid mediator prostaglandin E(2) (PGE(2)) and generation of cyclic adenosine monophosphate (cAMP) also accompany this process. Here, we characterized the mechanisms underlying PGE(2)-mediated inhibition of phagocytosis and filamentous actin (F-actin) polymerization in response to ingestion of C. albicans by alveolar macrophages. PGE(2) suppressed phagocytosis and F-actin formation through the PGE(2) receptors EP2 and EP4, cAMP, and activation of types I and II protein kinase A. Dephosphorylation and activation of the actin depolymerizing factor cofilin-1 were necessary for these inhibitory effects of PGE(2). PGE(2)-dependent activation of cofilin-1 was mediated by the protein phosphatase activity of PTEN (phosphatase and tensin homolog deleted on chromosome 10), with which it directly associated. Because enhanced production of PGE(2) accompanies many immunosuppressed states, the PTEN-dependent pathway described here may contribute to impaired antifungal defenses.
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Affiliation(s)
- C Henrique Serezani
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI 48109, USA
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Myeloid-derived suppressor cells express the death receptor Fas and apoptose in response to T cell-expressed FasL. Blood 2011; 117:5381-90. [PMID: 21450901 DOI: 10.1182/blood-2010-11-321752] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Myeloid-derived suppressor cells (MDSCs) inhibit adaptive and innate immunity and accumulate in the blood of persons with cancer, chronic inflammation, trauma, infection, and stress. Some of the factors inducing their accumulation are known; however, mechanisms regulating their turnover have not been identified. Mass spectrometry showed prominent expression of apoptosis pathway proteins, suggesting that MDSC turnover may be regulated by Fas-FasL-mediated apoptosis. This hypothesis was confirmed by showing that blood MDSCs induced by 3 mouse tumors were Fas(+) and apoptosed in response to Fas agonist in vitro and to activated FasL(+) T cells in vivo. FasL-deficient mice contained significantly more blood MDSCs than FasL(+/+) mice, and after removal of primary tumors MDSCs regressed in STAT6(-/-) and CD1(-/-) mice but not in STAT6(-/-)FasL(-/-) or CD1(-/-)FasL(-/-) mice. Fas(+) macrophages and dendritic cells did not apoptose in response to activated T cells, indicating that Fas-FasL regulation of myeloid cells was restricted to MDSCs. These results identify a new mechanism regulating MDSC levels in vivo and show a retaliatory relationship between T cells and MDSCs in that MDSCs suppress T-cell activation; however, once activated, T cells mediate MDSC apoptosis.
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Kopfnagel V, Werfel T, Wittmann M. Resting but not CpG stimulated keratinocytes suppress autologous T-helper cell proliferation--importance of PGE2 and T regulatory function. Exp Dermatol 2011; 20:394-400. [PMID: 21426407 DOI: 10.1111/j.1600-0625.2010.01220.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In the last decade, keratinocytes have increasingly been recognized to actively participate in the skin immune response. However, their influence on infiltrating lymphocytes - abundantly found in e.g. atopic and psoriatic inflammation - is still controversial. In this study, we aimed to investigate the influence of keratinocytes on T-cell proliferation by use of an autologous co-culture model. Because the skin has an important function with regard to detecting invading pathogens, we also investigated the influence of pathogen-associated molecular pattern on keratinocyte - T-cell interaction. We observed a clear inhibition of T-cell proliferation by co-cultured keratinocytes. This effect was found to be mediated by PGE2, as T-cell proliferation was recovered in the presence of the PGE2 inhibitor indometacin. Furthermore, presence of keratinocytes led to enhanced expression of the T regulatory cell-specific transcription factor Foxp3 in the CD4+CD25+ T-cell population which also showed regulatory function. Interestingly, the presence of the TLR9 ligand CpG was able to prevent the inhibition of T-cell proliferation. This was paralleled by a reduced PGE2 production by keratinocytes and a down-regulated T regulatory cell function. Our results indicate that the inhibitory capacity of keratinocytes in the skin is strongly influenced by the surrounding micromillieu.
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Affiliation(s)
- Verena Kopfnagel
- Department of Dermatology and Allergy, Division of Immunodermatology and Allergy Research, Hannover Medical School, Hannover, Germany.
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26
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Buzzo CL, Campopiano JC, Massis LM, Lage SL, Cassado AA, Leme-Souza R, Cunha LD, Russo M, Zamboni DS, Amarante-Mendes GP, Bortoluci KR. A novel pathway for inducible nitric-oxide synthase activation through inflammasomes. J Biol Chem 2010; 285:32087-95. [PMID: 20702413 DOI: 10.1074/jbc.m110.124297] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Innate immune recognition of flagellin is shared by transmembrane TLR5 and cytosolic Nlrc4 (NOD-like receptor family CARD (caspase activation recruitment domain) domain containing 4)/Naip5 (neuronal apoptosis inhibitory protein 5). TLR5 activates inflammatory genes through MYD88 pathway, whereas Nlrc4 and Naip5 assemble multiprotein complexes called inflammasomes, culminating in caspase-1 activation, IL-1β/IL-18 secretion, and pyroptosis. Although both TLR5 and Naip5/Nlrc4 pathways cooperate to clear infections, little is known about the relative anti-pathogen effector mechanisms operating through each of them. Here we show that the cytosolic flagellin (FLA-BSDot) was able to activate iNOS, an enzyme previously associated with TLR5 pathway. Using Nlrc4- or Naip5-deficient macrophages, we found that both receptors are involved in iNOS activation by FLA-BSDot. Moreover, distinct from extracellular flagellin (FLA-BS), iNOS activation by intracellular flagellin is completely abrogated in the absence of caspase-1. Interestingly, IL-1β and IL-18 do not seem to be important for FLA-BSDot-mediated iNOS production. Together, our data defined an additional anti-pathogen effector mechanism operated through Naip5 and Nlrc4 inflammasomes and illustrated a novel signaling transduction pathway that activates iNOS.
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Affiliation(s)
- Carina L Buzzo
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo 05508-900, Brazil
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27
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Pedrosa AMDC, Weinlich R, Mognol GP, Robbs BK, Viola JPDB, Campa A, Amarante-Mendes GP. Melatonin protects CD4+ T cells from activation-induced cell death by blocking NFAT-mediated CD95 ligand upregulation. THE JOURNAL OF IMMUNOLOGY 2010; 184:3487-94. [PMID: 20181888 DOI: 10.4049/jimmunol.0902961] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Over the past 20 y, the hormone melatonin was found to be produced in extrapineal sites, including cells of the immune system. Despite the increasing data regarding the biological effects of melatonin on the regulation of the immune system, the effect of this molecule on T cell survival remains largely unknown. Activation-induced cell death plays a critical role in the maintenance of the homeostasis of the immune system by eliminating self-reactive or chronically stimulated T cells. Because activated T cells not only synthesize melatonin but also respond to it, we investigated whether melatonin could modulate activation-induced cell death. We found that melatonin protects human and murine CD4(+) T cells from apoptosis by inhibiting CD95 ligand mRNA and protein upregulation in response to TCR/CD3 stimulation. This inhibition is a result of the interference with calmodulin/calcineurin activation of NFAT that prevents the translocation of NFAT to the nucleus. Accordingly, melatonin has no effect on T cells transfected with a constitutively active form of NFAT capable of migrating to the nucleus and transactivating target genes in the absence of calcineurin activity. Our results revealed a novel biochemical pathway that regulates the expression of CD95 ligand and potentially other downstream targets of NFAT activation.
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Affiliation(s)
- Alziana Moreno da Cunha Pedrosa
- Departamento de Análises Clínica e Toxicológica, Faculdade de Ciências Farmacêuticas, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo Brazil
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Huang SK, White ES, Wettlaufer SH, Grifka H, Hogaboam CM, Thannickal VJ, Horowitz JC, Peters-Golden M. Prostaglandin E(2) induces fibroblast apoptosis by modulating multiple survival pathways. FASEB J 2009; 23:4317-26. [PMID: 19671668 DOI: 10.1096/fj.08-128801] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Although the lipid mediator prostaglandin E(2) (PGE(2)) exerts antifibrotic effects by inhibiting multiple fibroblast functions, its ability to regulate fibroblast survival is unknown. Here, we examined the effects of this prostanoid on apoptosis and apoptosis pathways in normal and fibrotic lung fibroblasts. As compared to medium alone, 24 h of treatment with PGE(2) increased apoptosis of normal lung fibroblasts in a dose-dependent manner (EC(50) approximately 50 nM), as measured by annexin V staining, caspase 3 activity, cleavage of poly-ADP-ribose polymerase, and single-stranded DNA levels. PGE(2) also potentiated apoptosis elicited by Fas ligand plus cycloheximide. These proapoptotic actions were dependent on signaling through the EP2/EP4 receptors and by downstream activation of both caspases 8 and 9. Silencing and gene deletion of PTEN demonstrated that the effects of PGE(2) involved decreased activity of the prosurvival molecule Akt. PGE(2) also down-regulated expression of survivin, an inhibitor of apoptosis, and increased expression of Fas. Fibroblasts from patients with pulmonary fibrosis exhibited resistance to the apoptotic effects of PGE(2). These findings show for the first time that, in contrast to its effects on many other cell types, PGE(2) promotes apoptosis in lung fibroblasts through diverse pathways. They provide another dimension by which PGE(2) may inhibit, and perhaps even reverse, fibrogenesis in patients with interstitial lung disease.
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Affiliation(s)
- Steven K Huang
- Pulmonary and Critical Care Medicine, University of Michigan, 6301 MSRB III, 1150 W. Medical Center Dr., Ann Arbor, MI 48109-5642, USA
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