1
|
Tang C, Wang Y, Chen D, Zhang M, Xu J, Xu C, Liu J, Kan J, Jin C. Natural polysaccharides protect against diet-induced obesity by improving lipid metabolism and regulating the immune system. Food Res Int 2023; 172:113192. [PMID: 37689942 DOI: 10.1016/j.foodres.2023.113192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/25/2023] [Accepted: 06/27/2023] [Indexed: 09/11/2023]
Abstract
Unhealthy dietary patterns-induced obesity and obesity-related complications pose a great threat to human health all over the world. Accumulating evidence suggests that the pathophysiology of obesity and obesity-associated metabolic disorders is closely associated with dysregulation of lipid and energy metabolism, and metabolic inflammation. In this review, three potential anti-obesity mechanisms of natural polysaccharides are introduced. Firstly, natural polysaccharides protect against diet-induced obesity directly by improving lipid and cholesterol metabolism. Since the immunity also affects lipid and energy metabolism, natural polysaccharides improve lipid and energy metabolism by regulating host immunity. Moreover, diet-induced mitochondrial dysfunction, prolonged endoplasmic reticulum stress, defective autophagy and microbial dysbiosis can disrupt lipid and/or energy metabolism in a direct and/or inflammation-induced manner. Therefore, natural polysaccharides also improve lipid and energy metabolism and suppress inflammation by alleviating mitochondrial dysfunction and endoplasmic reticulum stress, promoting autophagy and regulating gut microbiota composition. Specifically, this review comprehensively summarizes underlying anti-obesity mechanisms of natural polysaccharides and provides a theoretical basis for the development of functional foods. For the first time, this review elucidates anti-obesity mechanisms of natural polysaccharides from the perspectives of their hypolipidemic, energy-regulating and immune-regulating mechanisms.
Collapse
Affiliation(s)
- Chao Tang
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Yuxin Wang
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Dan Chen
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Man Zhang
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Jingguo Xu
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Chen Xu
- Nanjing Key Laboratory of Quality and safety of agricultural product, Nanjing Xiaozhuang University, Nanjing 211171, China.
| | - Jun Liu
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Juan Kan
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Changhai Jin
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| |
Collapse
|
2
|
Abstract
Despite enduring diverse insults, mitochondria maintain normal functions through mitochondrial quality control. However, the failure of mitochondrial quality control resulting from excess damage and mechanical defects causes mitochondrial dysfunction, leading to various human diseases. Recent studies have reported that mitochondrial defects are found in Alzheimer’s disease (AD) and worsen AD symptoms. In AD pathogenesis, mitochondrial dysfunction-driven generation of reactive oxygen species (ROS) and their contribution to neuronal damage has been widely studied. In contrast, studies on mitochondrial dysfunction-associated inflammatory responses have been relatively scarce. Moreover, ROS produced upon failure of mitochondrial quality control may be linked to the inflammatory response and influence the progression of AD. Thus, this review will focus on inflammatory pathways that are associated with and initiated through defective mitochondria and will summarize recent progress on the role of mitochondria-mediated inflammation in AD. We will also discuss how reducing mitochondrial dysfunction-mediated inflammation could affect AD.
Collapse
Affiliation(s)
- Seung-Min Yoo
- School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Jisu Park
- School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Seo-Hyun Kim
- School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Yong-Keun Jung
- School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| |
Collapse
|
3
|
Chen Y, Lu S, Zhang Y, Yu J, Deng L, Chen H, Zhang Y, Zhou N, Yuan K, Yu L, Xiong Z, Gui X, Yu Y, Min W. TLR2 agonist Pam3CSK4 enhances the antibacterial functions of GM-CSF induced neutrophils to methicillin-resistant Staphylococcus aureus. Microb Pathog 2019; 130:204-12. [PMID: 30885749 DOI: 10.1016/j.micpath.2019.02.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 01/21/2019] [Accepted: 02/25/2019] [Indexed: 01/15/2023]
Abstract
A proliferation of studies have demonstrated that the toll-like receptor 2 (TLR2) pathway affects the chemotaxis, phagocytosis, and cytokine release of neutrophils when pathogens invade. Our previous studies have demonstrated that pretreatment with high doses of Pam3CSK4 (>25 μg/ml) improves the antimicrobial activity of neutrophils, however, short-lived neutrophils limit their therapeutic functions. Here, we used granulocyte macrophage-colony stimulating factor (GM-CSF) to generate neutrophils from murine bone marrow, and assessed their effect on the immune response against methicillin-resistant Staphylococcus aureus. As comparing with classical method of generating neutrophils directly from murine bone marrow, our findings show that pretreatment with Pam3CSK4 enhanced the phagocytic and killing activities against MRSA by the GM-CSF induced neutrophils (GM-CSF neutrophils). Chemotaxis of GM-CSF induced neutrophils was significantly increased after the pretreatment with Pam3CSK4. Furthermore, Pam3CSK4 pretreatment enhanced iNOS, CRAMP, TNF-α, IL-1β, IL-10, and IL-6 expression. Finally, we observed that p38MAPK and Akt phosphorylation kinases were increased significantly in GM-CSF neutrophils pretreatment with Pam3CSK4 in a dose- and time-dependent manner, whereas p38MAPK inhibitor (SB2021190) and PI3K inhibitor (LY294002) attenuated the antimicrobial activities including phagocytosis, killing activity, respiratory burst, and the release of lactoferrin(LTF) by the GM-CSF induced neutrophils. Together, these findings suggest that pretreatment with Pam3CSK4 enhances the antibacterial function of GM-CSF neutrophils against MRSA, and this could be related to the p38MAPK and PI3K signaling pathways.
Collapse
|
4
|
Faour WH, Fayyad-Kazan H, El Zein N. fMLP-dependent activation of Akt and ERK1/2 through ROS/Rho A pathways is mediated through restricted activation of the FPRL1 (FPR2) receptor. Inflamm Res 2018; 67:711-22. [PMID: 29922854 DOI: 10.1007/s00011-018-1163-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 05/02/2018] [Accepted: 06/12/2018] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVE AND DESIGN The objective of this study is to uncover the signal transduction pathways of N-formyl methionyl-leucyl-phenylalanine (fMLP) in monocyte. MATERIALS OR SUBJECTS Freshly isolated human peripheral blood monocytes (PBMC) were used for in vitro assessment of signal transduction pathways activated by fMLP. TREATMENT Time-course and dose-response experiments were used to evaluate the effect of fMLP along with the specific inhibitors/stimulators on the activation of downstream signaling kinases. METHODS Freshly isolated human PBMC were stimulated with fMLP for the desired time. Western blot and siRNA analysis were used to evaluate the activated intracellular signaling kinases, and flow analysis was performed to assess the levels of CD11b. Furthermore, luminescence spectrometry was performed to measure the levels of released hydrogen peroxide in the media. RESULTS fMLP strongly stimulated the activation of AKT and ERK1/2 through a RhoA-GTPase-dependent manner and also induced H2O2 release by monocytes. Furthermore, fMLP mediated its effects through restricted activation of formylpeptide receptor-like 1 (FPRL1/FPR2), but independently of either EGFR transactivation or intracellular calcium release. In addition, NAC reversed fMLP- and H2O2-induced activation of Akt and RhoA-GTPase. CONCLUSION Collectively, these data suggested that fMLP-activated ERK1/2 and Akt pathways through specific activation of the FPRL1/ROS/RoA-GTPase pathway.
Collapse
|
5
|
Pan Y, Xu C, Pan ZK. MKP-1 negative regulates Staphylococcus aureus induced inflammatory responses in Raw264.7 cells: roles of PKA-MKP-1 pathway and enhanced by rolipram. Sci Rep 2017; 7:12366. [PMID: 28959039 PMCID: PMC5620070 DOI: 10.1038/s41598-017-10187-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 08/02/2017] [Indexed: 11/22/2022] Open
Abstract
MAP phosphatases (MKP)-1 acts as an important regulator of innate immune response through a mechanism of control and attention both MAPK and NF-κB molecules during bacterial infection. However, the regulatory role of MKP-1 in the interplay between MAPK and NFκB pathway molecules is still not fully understood. In present study, we showed a direct interactions of p38, ERK or IκBα with MKP-1, and demonstrated that MKP-1 was a pivotal feedback control for both MAP kinases and NF-κB pathway in response to S. aureus. In addition, we found that rolipram had anti-inflammatory activity and repressed IκBα activation induced by S. aureus via PKA-MKP-1 pathway. Our report also demonstrated that PKA-cα can directly bind to IκBα upon S. aureus stimulation, which influenced the downstream signaling of PKA pathway, including altered the expression of MKP-1. These results presented a novel mechanism of PKA and IκB pathway, which may be targeted for treating S. aureus infection.
Collapse
Affiliation(s)
- Yiqing Pan
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine, Toledo, OH, 43614, USA
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai, 200025, China
| | - Chen Xu
- Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai, 200025, China.
| | - Zhixing K Pan
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine, Toledo, OH, 43614, USA.
| |
Collapse
|
6
|
Wilkins HM, Weidling IW, Ji Y, Swerdlow RH. Mitochondria-Derived Damage-Associated Molecular Patterns in Neurodegeneration. Front Immunol 2017; 8:508. [PMID: 28491064 PMCID: PMC5405073 DOI: 10.3389/fimmu.2017.00508] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 04/12/2017] [Indexed: 12/21/2022] Open
Abstract
Inflammation is increasingly implicated in neurodegenerative disease pathology. As no acquired pathogen appears to drive this inflammation, the question of what does remains. Recent advances indicate damage-associated molecular pattern (DAMP) molecules, which are released by injured and dying cells, can cause specific inflammatory cascades. Inflammation, therefore, can be endogenously induced. Mitochondrial components induce inflammatory responses in several pathological conditions. Due to evidence such as this, a number of mitochondrial components, including mitochondrial DNA, have been labeled as DAMP molecules. In this review, we consider the contributions of mitochondrial-derived DAMPs to inflammation observed in neurodegenerative diseases.
Collapse
Affiliation(s)
- Heather M Wilkins
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA
| | - Ian W Weidling
- University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Yan Ji
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA
| | - Russell H Swerdlow
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA.,University of Kansas Alzheimer's Disease Center, Kansas City, KS, USA.,Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, USA.,Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, USA
| |
Collapse
|
7
|
Halligan DN, Murphy SJE, Taylor CT. The hypoxia-inducible factor (HIF) couples immunity with metabolism. Semin Immunol 2016; 28:469-477. [PMID: 27717536 DOI: 10.1016/j.smim.2016.09.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 09/23/2016] [Accepted: 09/30/2016] [Indexed: 12/16/2022]
Abstract
Crosstalk between metabolic and immune pathways has recently become appreciated to be key to the regulation of host defence. The hypoxia-inducible factor (HIF) is a transcription factor which was initially described as a ubiquitous master regulator of the transcriptional response to hypoxia. In this role, HIF regulates genes promoting adaptation to hypoxia including a number which influence the cellular metabolic strategy of a cell. It has more recently been appreciated that the regulation of HIF is not restricted to oxygen-dependent pathways, and is now known to be mediated by a number of additional metabolic and immune cues including metabolites and cytokines respectively. Furthermore, our understanding of the functional role of HIF has expanded to it now being appreciated as a major regulator of host immunity. This places HIF in an ideal position to act as a regulatory hub which links metabolic activity with immunity. In this review we synthesise recent data which identifies HIF as both a target and effector for metabolic and immune processes. Developing our understanding of the role of HIF in this context will uncover new therapeutic targets for inflammatory and infectious disease.
Collapse
Affiliation(s)
- Doug N Halligan
- Conway Institute, Charles Institute & Systems Biology Ireland, University College Dublin, Belfield Dublin 4, Ireland; Sigmoid Pharma, Invent Centre, Dublin City University, Dublin 9, Ireland
| | - Stephen J E Murphy
- Conway Institute, Charles Institute & Systems Biology Ireland, University College Dublin, Belfield Dublin 4, Ireland
| | - Cormac T Taylor
- Conway Institute, Charles Institute & Systems Biology Ireland, University College Dublin, Belfield Dublin 4, Ireland; IRCAN, Centre A. Lacassagne, University of Nice-Sophia Antipolis, 33 Avenue Valombrose, 06107 Nice, France; Centre Scientifique de Monaco (CSM), 8, Quai Antoine Premier, Monaco.
| |
Collapse
|
8
|
Nosworthy MG, Brunton JA. Cysteinyl-glycine reduces mucosal proinflammatory cytokine response to fMLP in a parenterally-fed piglet model. Pediatr Res 2016; 80:293-8. [PMID: 27055186 DOI: 10.1038/pr.2016.69] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 02/02/2016] [Indexed: 11/09/2022]
Abstract
BACKGROUND PepT1 transports dietary and bacterial peptides in the gut. We hypothesized that cysteinyl-glycine would ameliorate the inflammatory effect of a bacterial peptide, formyl-methionyl-leucyl-phenylalanine (fMLP), in both sow-fed and parenterally-fed piglets. METHODS An intestinal perfusion experiment was performed in piglets (N = 12) that were sow-reared or provided with parenteral nutrition (PN) for 4 d. In each piglet, five segments of isolated intestine were perfused with five treatments including cysteine and glycine, cysteinyl-glycine, fMLP, free cysteine and glycine with fMLP, or cysteinyl-glycine with fMLP. Mucosal cytokine responses and intestinal morphology was assessed in each gut segment. RESULTS PN piglets had lower mucosal IL-10 by approximately 20% (P < 0.01). Cysteinyl-glycine lowered TNF-α response to fMLP in PN-fed animals and IFN-γ response to fMLP in both groups (P < 0.05). The free cysteine and glycine treatment reduced TNF-α in sow-fed animals (P < 0.05). fMLP affected villus height in parenterally (P < 0.05), but not sow-fed animals. CONCLUSION Parenteral feeding conferred a susceptibility to mucosal damage by fMLP. The dipeptide was more effective at attenuating the inflammatory response to a bacterial peptide than free amino acids. This may be due to competitive inhibition of fMLP transport or a greater efficiency of transport of dipeptides.
Collapse
Affiliation(s)
- Matthew G Nosworthy
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Janet A Brunton
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| |
Collapse
|
9
|
Wilkins HM, Carl SM, Greenlief ACS, Festoff BW, Swerdlow RH. Bioenergetic dysfunction and inflammation in Alzheimer's disease: a possible connection. Front Aging Neurosci 2014; 6:311. [PMID: 25426068 PMCID: PMC4226164 DOI: 10.3389/fnagi.2014.00311] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 10/23/2014] [Indexed: 11/29/2022] Open
Abstract
Inflammation is observed in Alzheimer’s disease (AD) subject brains. Inflammation-relevant genes are increasingly implicated in AD genetic studies, and inflammatory cytokines to some extent even function as peripheral biomarkers. What underlies AD inflammation is unclear, but no “foreign” agent has been implicated. This suggests that internally produced damage-associated molecular pattern (DAMPs) molecules may drive inflammation in AD. A more complete characterization and understanding of AD-relevant DAMPs could advance our understanding of AD and suggest novel therapeutic strategies. In this review, we consider the possibility that mitochondria, intracellular organelles that resemble bacteria in many ways, trigger and maintain chronic inflammation in AD subjects. Data supporting the possible nexus between AD-associated bioenergetic dysfunction are discussed.
Collapse
Affiliation(s)
- Heather M Wilkins
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Steven M Carl
- University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Alison C S Greenlief
- University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA
| | - Barry W Festoff
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Pharmacology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Molecular and Integrative Physiology, University of Kansas Medical Center , Kansas City, KS , USA ; pHLOGISTIX Neurodiagnostics , Lenexa, KS , USA
| | - Russell H Swerdlow
- Department of Neurology, University of Kansas Medical Center , Kansas City, KS , USA ; University of Kansas Alzheimer's Disease Center, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Molecular and Integrative Physiology, University of Kansas Medical Center , Kansas City, KS , USA ; Department of Biochemistry and Molecular Biology, University of Kansas Medical Center , Kansas City, KS , USA
| |
Collapse
|
10
|
Pan ZK, Fisher C, Li JD, Jiang Y, Huang S, Chen LY. Bacterial LPS up-regulated TLR3 expression is critical for antiviral response in human monocytes: evidence for negative regulation by CYLD. Int Immunol 2011; 23:357-64. [PMID: 21498625 DOI: 10.1093/intimm/dxr019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the host immune system, the leukocytes are often exposed to multiple pathogens including bacteria and viruses. The principal challenge for the host is to efficiently detect the invading pathogen and mount a rapid defensive response. Leukocytes recognize invading pathogens by directly interacting with pathogen-associated molecular patterns via Toll-like receptors (TLRs) expressed on the leukocyte surfaces. In this study, we provide direct evidence that bacterial LPS enhances the host antiviral response by up-regulating TLR3 expression in human peripheral blood monocytes and monocytic cell lines, THP1 cells. Moreover, LPS induces TLR3 expression via a TLR4-MyD88-IRAK-TRAF6-NF-κB-dependent signaling pathway. Interestingly, CYLD, an important deubiquitinase, acts as a negative regulator of TLR3 induction by LPS. Our study thus provides new insights into a novel role for bacterial infection in enhancing host antiviral response; furthermore, it identifies CYLD for the first time as a critical negative regulator of bacterial LPS-induced response.
Collapse
Affiliation(s)
- Zhixing K Pan
- Department of Medical Microbiology and Immunology and Medicine, University of Toledo Medical Center, Toledo, OH 43614, USA
| | | | | | | | | | | |
Collapse
|
11
|
Pan WW, Li JD, Huang S, Papadimos TJ, Pan ZK, Chen LY. Synergistic activation of NF-{kappa}B by bacterial chemoattractant and TNF{alpha} is mediated by p38 MAPK-dependent RelA acetylation. J Biol Chem 2010; 285:34348-54. [PMID: 20729202 DOI: 10.1074/jbc.m110.109165] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the host immune system, leukocytes are often exposed to multiple inflammation inducers. NF-κB is of considerable importance in leukocyte function because of its ability to activate the transcription of many proinflammatory immediate-early genes. Tremendous efforts have been made toward understanding how NF-κB is activated by various inducers. However, most research on NF-κB regulation has been focused on understanding how NF-κB is activated by a single inducer. This is unlike the situation in the human immune system where multiple inflammation inducers, including both exogenous and endogenous mediators, are present concurrently. We now present evidence that the formylated peptide f-Met-Leu-Phe (fMLP), a bacterial chemoattractant, synergizes with TNFα to induce NF-κB activation and the resultant inflammatory response in vitro and in vivo. The mechanism of synergistic activation of NF-κB by bacterial fMLP and TNFα may be involved in the induction of RelA acetylation, which is regulated by p38 MAPK. Thus, this study provides direct evidence for the synergistic induction of NF-κB-dependent inflammatory responses by both exogenous and endogenous inducers. The ability of fMLP to synergize with TNFα and activate NF-κB represents a novel and potentially important mechanism through which bacterial fMLP not only attracts leukocytes but also directly contributes to inflammation by synergizing with the endogenous mediator TNFα.
Collapse
Affiliation(s)
- Warren W Pan
- Department of Medicine, University of Toledo Medical Center, Toledo, Ohio 43614, USA
| | | | | | | | | | | |
Collapse
|
12
|
Komoda H, Inoue T, Node K. Anti-Inflammatory Properties of Azelnidipine, a Dihydropyridine-Based Calcium Channel Blocker. Clin Exp Hypertens 2010; 32:121-8. [DOI: 10.3109/10641960903254414] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
13
|
Cui Y, Hou X, Chen J, Xie L, Yang L, Le Y. Sesamin inhibits bacterial formylpeptide-induced inflammatory responses in a murine air-pouch model and in THP-1 human monocytes. J Nutr 2010; 140:377-81. [PMID: 20032476 DOI: 10.3945/jn.109.117804] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The reaction of human leukocytes to chemoattractants is an important component of the host immune response and also plays a crucial role in the development of inflammation. Sesamin has been shown to inhibit lipid peroxidation and regulate cytokine production. In this study, we examined the effect of sesamin on inflammatory responses elicited by the bacterial chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (fMLF) in vitro and in vivo and explored the mechanisms involved. fMLF is recognized by a human G protein-coupled receptor formyl peptide receptor (FPR) on phagocytic leukocytes. Sesamin at concentrations between 12.5 and 50 micromol/L inhibited fMLF-induced chemotaxis of human monocyte cell line THP-1 differentiated with dibutyryl cyclic AMP (P < 0.01). Similarly, sesamin inhibited FPR-transfected rat basophilic leukemia cell [epitope-tagged human FPR (ETFR) cell] migration toward fMLF (P < 0.01). In fMLF-induced inflammation in a murine air-pouch model, intraperitoneal administration of sesamin (12 mgkg(-1)d(-1) for 2 d) suppressed leukocyte infiltration into the air pouch induced by fMLF [(62.89 +/- 7.93) x 10(4) vs. (19.67 +/- 4.43) x 10(4) cells/air pouch; n = 9; P < 0.001]. Ca(2+) mobilization and mitogen-activated protein kinase extracellular signal-regulated kinase (ERK1/2) activation are involved in fMLF-induced leukocyte migration. Pretreatment of ETFR cells with sesamin inhibited fMLF-induced ERK1/2 phosphorylation in a dose-dependent manner but did not affect fMLF-induced Ca(2+) flux. Electrophoretic mobility shift assay showed that pretreatment of THP-1 cells with sesamin dose dependently inhibited fMLF-induced nuclear factor-kappaB (NF-kappaB) activation. These results suggest that sesamin inhibits leukocyte activation by fMLF through ERK1/2- and NF-kappaB-related signaling pathways and thus is a potential compound for the management of inflammatory diseases.
Collapse
Affiliation(s)
- Youhong Cui
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Shanghai, 200031, China
| | | | | | | | | | | |
Collapse
|
14
|
Huang X, Chen LY, Doerner AM, Pan WW, Smith L, Huang S, Papadimos TJ, Pan ZK. An Atypical Protein Kinase C (PKCζ) Plays a Critical Role in Lipopolysaccharide-Activated NF-κB in Human Peripheral Blood Monocytes and Macrophages. J Immunol 2009; 182:5810-5. [DOI: 10.4049/jimmunol.0804073] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
15
|
Chen LY, Pan WW, Chen M, Li JD, Liu W, Chen G, Huang S, Papadimos TJ, Pan ZK. Synergistic induction of inflammation by bacterial products lipopolysaccharide and fMLP: an important microbial pathogenic mechanism. J Immunol 2009; 182:2518-24. [PMID: 19201908 DOI: 10.4049/jimmunol.0713933] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A wide variety of stimuli have been shown to induce inflammation, but bacteria products/components are considered the major inducers during bacterial infections. We previously demonstrated that bacterial products/components such as LPS, a glycolipid component of the bacterial outer membrane, and formylated peptides (fMLP), a bacterial-derived peptide, induced proinflammatory cytokine gene expression in human peripheral blood monocytes. We now present evidence that mixtures of bacterial products/components LPS and fMLP behave synergistically in the induction of inflammation in vitro and in vivo. Furthermore, our results indicate that the TLR4 and the IKKbeta-IkappaBalpha signaling pathways are involved in the synergistic induction of inflammatory cytokines. The mechanism of synergistic activation of NF-kappaB is depended on nuclear translocation of p65 and phosphorylation of p65 at both Ser536 and Ser276 sites. These results demonstrate an important role for bacterial products/components from lysed bacteria in the pathogenesis of infectious diseases. We believe that this synergistic induction of inflammation by bacterial products LPS and fMLP represents an important pathogenic mechanism during bacterial infection, which may suggest novel therapeutic strategies or targets to minimize host injury following bacterial infection.
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Medical Microbiology and Immunology, Medical University of Ohio, Toledo, OH 43614, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Cheung R, Ravyn V, Wang L, Ptasznik A, Collman RG. Signaling mechanism of HIV-1 gp120 and virion-induced IL-1beta release in primary human macrophages. J Immunol 2008; 180:6675-84. [PMID: 18453587 DOI: 10.4049/jimmunol.180.10.6675] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HIV-1 envelope glycoprotein gp120 induces, independently of infection, the release of proinflammatory cytokines, including IL-1beta from macrophages, that are implicated in the pathogenesis of HIV-associated dementia. However, the signal transduction pathways involved have not been fully defined. Previously, our laboratory reported that soluble gp120 activates multiple protein kinases in primary human monocyte-derived macrophages, including the Src family kinase Lyn, PI3K, and the focal adhesion-related proline-rich tyrosine kinase Pyk2. In this study we showed that gp120 induces IL-1beta release from macrophages in a time- and concentration-dependent manner through binding to the chemokine receptor CCR5 and coupling to G(i)alpha protein. Using pharmacological inhibitors and small interfering RNA gene knockdown, we demonstrated that concomitant activation of Lyn, Pyk2, and class IA PI3K are required for gp120-induced IL-1beta production. By coimmunoprecipitation and immunofluorescence confocal microscopy, we showed that CCR5 activation by gp120 triggered the assembly of a signaling complex involving endogenous Lyn, PI3K, and Pyk2 and is associated with PI3K and Pyk2 translocation from the cytoplasm to the membrane where they colocalized with Lyn. Finally, we demonstrated that virion-associated gp120 induced similar response, as structurally intact whole virions also triggered IL-1beta release and re-localization of PI3K and Pyk2. This study identifies a novel signaling mechanism for HIV-1-induced IL-1beta production by primary human macrophages that may be involved in the neuropathogenesis of HIV-associated dementia.
Collapse
Affiliation(s)
- Ricky Cheung
- Pulmonary, Allergy, and Critical Care, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | | | | | | | | |
Collapse
|
17
|
Huang J, Chen K, Gong W, Zhou Y, Le Y, Bian X, Wang JM. Receptor "hijacking" by malignant glioma cells: a tactic for tumor progression. Cancer Lett 2008; 267:254-61. [PMID: 18433988 DOI: 10.1016/j.canlet.2008.03.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 02/26/2008] [Accepted: 03/11/2008] [Indexed: 01/25/2023]
Abstract
Gliomas are the most common and deadly tumors in the central nervous system (CNS). In the course of studying the role of chemoattractant receptors in tumor growth and metastasis, we discovered that highly malignant human glioblastoma and anaplastic astrocytoma specimens were stained positively for the formylpeptide receptor (FPR), which is normally expressed in myeloid cells and accounts for their chemotaxis and activation induced by bacterial peptides. Screening of human glioma cell lines revealed that FPR was expressed selectively in glioma cell lines with a more highly malignant phenotype. FPR expressed in glioblastoma cell lines mediates cell chemotaxis, proliferation and production of an angiogenic factor, vascular endothelial growth factor (VEGF), in response to agonists released by necrotic tumor cells. Furthermore, FPR in glioblastoma cells activates the receptor for epidermal growth factor (EGFR) by increasing the phosphorylation of a selected tyrosine residue in the intracellular tail of EGFR. Thus, FPR hijacked by human glioblastoma cells exploits the function of EGFR to promote rapid tumor progression.
Collapse
Affiliation(s)
- Jian Huang
- Laboratory of Molecular Immunoregulation, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute at Frederick, Building 560, Room 31-76, Frederick, MD 21702-1201, USA
| | | | | | | | | | | | | |
Collapse
|
18
|
Kam AYF, Liu AMF, Wong YH. Formyl peptide-receptor like-1 requires lipid raft and extracellular signal-regulated protein kinase to activate inhibitor-κB kinase in human U87 astrocytoma cells. J Neurochem 2007; 103:1553-66. [PMID: 17727628 DOI: 10.1111/j.1471-4159.2007.04876.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Formyl peptide-receptor like-1 (FPRL-1) may possess critical roles in Alzheimer's diseases, chemotaxis and release of neurotoxins, possibly through its regulation of nuclear factor-kappaB (NFkappaB). Here we illustrate that activation of FPRL-1 in human U87 astrocytoma or Chinese hamster ovary cells stably expressing the receptor resulted in the phosphorylations of inhibitor-kappaB kinase (IKK), an onset kinase for NFkappaB signaling cascade. FPRL-1 selective hexapeptide Trp-Lys-Tyr-Met-Val-Met (WKYMVM) promoted IKK phosphorylations in time- and dose-dependent manners while pre-treatment of pertussis toxin abrogated the Galpha(i/o)-dependent stimulations. The FPRL-1-mediated IKK phosphorylation required extracellular signal-regulated protein kinase (ERK), phosphatidylinositol 3-kinase and cellular Src (c-Src), but not c-Jun N-terminal kinase and p38 mitogen-activated protein kinase. Despite its ability to mobilize Ca(2+), WKYMVM did not require Ca(2+) for the modulation of IKK phosphorylation. Activation of FPRL-1 also induced NFkappaB-driven luciferase expression. Interestingly, cholesterol depletion from plasma membrane by methyl-beta-cyclodextrin abolished the FPRL-1-stimulated IKK phosphorylation, denoting the important role of lipid raft integrity in the FPRL-1 to IKK signaling. Furthermore, we demonstrated that in U87 cells, several signaling intermediates in the FPRL-1-IKK pathway including Galpha(i2), c-Src and ERK were constitutively localized at the raft microdomains. WKYMVM administration not only resulted in higher amount of ERK recruitment to the raft region, but also specifically stimulated raft-associated c-Src and ERK phosphorylations. Taken together, these results demonstrate that FPRL-1 is capable of activating NFkappaB signaling through IKK phosphorylation and this may serve as a useful therapeutical target for FPRL-1-related diseases.
Collapse
Affiliation(s)
- Angel Y F Kam
- Department of Biochemistry, the Molecular Neuroscience Center, and the Biotechnology Research Institute, Hong Kong University of Science and Technology, Hong Kong, China
| | | | | |
Collapse
|
19
|
Gauthier JF, Fortin A, Bergeron Y, Dumas MC, Champagne ME, Bergeron MG. Differential contribution of bacterial N-formyl-methionyl-leucyl- phenylalanine and host-derived CXC chemokines to neutrophil infiltration into pulmonary alveoli during murine pneumococcal pneumonia. Infect Immun 2007; 75:5361-7. [PMID: 17709413 PMCID: PMC2168265 DOI: 10.1128/iai.02008-06] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Despite the development of new potent antibiotics, Streptococcus pneumoniae remains the leading cause of death from bacterial pneumonia. Polymorphonuclear neutrophil (PMN) recruitment into the lungs is a primordial step towards host survival. Bacterium-derived N-formyl peptides (N-formyl-methionyl-leucyl-phenylalanine [fMLP]) and host-derived chemokines (KC and macrophage inflammatory protein 2 [MIP-2]) are likely candidates among chemoattractants to coordinate PMN infiltration into alveolar spaces. To investigate the contribution of each in the context of pneumococcal pneumonia, CD1, BALB/c, CBA/ca, C57BL/6, and formyl peptide receptor (FPR)-knockout C57BL/6 mice were infected with 10(6) or 10(7) CFU of penicillin/erythromycin-susceptible or -resistant serotype 3 or 14 S. pneumoniae strains. Antagonists to the FPR, such as cyclosporine H (CsH) and chenodeoxycholic acid, or neutralizing antibodies to KC and MIP-2 were injected either 1 h before or 30 min after infection, and then bronchoalveolar lavage fluids were obtained for quantification of bacteria, leukocytes, and chemokines. CsH was effective over a short period after infection with a high inoculum, while anti-CXC chemokine antibodies were effective after challenge with a low inoculum. CsH prevented PMN infiltration in CD1 mice infected with either serotype 3 or 14, whereas antichemokine antibodies showed better efficacy against the serotype 3 strain. When different mouse strains were challenged with serotype 3 bacteria, CsH prevented PMN migration in the CD1 mice only, whereas the antibodies were effective against CD1 and C57BL/6 mice. Our results suggest that fMLP and chemokines play important roles in pneumococcal pneumonia and that these roles vary according to bacterial and host genetic backgrounds, implying redundancy among chemoattractant molecules.
Collapse
|
20
|
Abstract
Ligation of N-formyl-methionyl-leucyl-phenylalanine (fMLP) to its specific cell surface receptors triggers different cascades of biochemical events, eventually leading to cellular activation. The formyl peptide receptors (FPRs) are members of the seven-transmembrane, G-protein coupled receptors superfamily, expressed at high levels on polymorphonuclear and mononuclear phagocytes. The main responses elicited upon ligation of formylated peptides, referred to as cellular activation, are those of morphological polarization, locomotion, production of reactive-oxygen species and release of proteolytic enzymes. FPRs have in recent years been shown to be expressed also in several non myelocytic populations, suggesting other unidentified functions for this receptor family, independent of the inflammatory response. Finally, a number of ligands acting as exogenous or host-derived agonists for FPRs, as well as ligands acting as FPRs antagonists, have been described, indicating that these receptors may be differentially modulated by distinct molecules.
Collapse
Affiliation(s)
- M A Panaro
- Department of Human Anatomy and Histology, University of Bari, Italy.
| | | | | | | | | | | |
Collapse
|
21
|
Harokopakis E, Albzreh MH, Martin MH, Hajishengallis G. TLR2 transmodulates monocyte adhesion and transmigration via Rac1- and PI3K-mediated inside-out signaling in response to Porphyromonas gingivalis fimbriae. J Immunol 2006; 176:7645-56. [PMID: 16751412 DOI: 10.4049/jimmunol.176.12.7645] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We present evidence for a novel TLR2 function in transmodulating the adhesive activities of human monocytes in response to the fimbriae of Porphyromonas gingivalis, a pathogen implicated in chronic periodontitis and atherosclerosis. Monocyte recruitment into the subendothelium is a crucial step in atherosclerosis, and we investigated the role of P. gingivalis fimbriae in stimulating monocyte adhesion to endothelial cells and transendothelial migration. Fimbriae induced CD11b/CD18-dependent adhesion of human monocytes or mouse macrophages to endothelial receptor ICAM-1; these activities were inhibited by TLR2 blockade or deficiency or by pharmacological inhibitors of PI3K. Moreover, this inducible adhesive activity was sensitive to the action of Clostridium difficile toxin B, but was not affected by Clostridium botulinum C3 exoenzyme, pertussis toxin, or cholera toxin. Accordingly, we subsequently showed through the use of dominant negative signaling mutants of small GTPases, that Rac1 mediates the ability of fimbria-stimulated monocytes to bind ICAM-1. A dominant negative mutant of Rac1 also inhibited the lipid kinase activity of PI3K suggesting that Rac1 acts upstream of PI3K in this proadhesive pathway. Furthermore, fimbriae stimulated monocyte adhesion to HUVEC and transmigration across HUVEC monolayers; both activities required TLR2 and Rac1 signaling and were dependent upon ICAM-1 and the high-affinity state of CD11b/CD18. P. gingivalis-stimulated monocytes displayed enhanced transendothelial migration compared with monocytes stimulated with nonfimbriated isogenic mutants. Thus, P. gingivalis fimbriae activate a novel proadhesive pathway in human monocytes, involving TLR2, Rac1, PI3K, and CD11b/CD18, which may constitute a mechanistic basis linking P. gingivalis to inflammatory atherosclerotic processes.
Collapse
Affiliation(s)
- Evlambia Harokopakis
- Center for Oral Health and Systemic Disease, University of Louisville Health Sciences Center, KY 40292, USA
| | | | | | | |
Collapse
|
22
|
Liu AMF, Wong YH. Mu-opioid receptor-mediated phosphorylation of IkappaB kinase in human neuroblastoma SH-SY5Y cells. Neurosignals 2005; 14:136-42. [PMID: 16088228 DOI: 10.1159/000086296] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Accepted: 04/11/2005] [Indexed: 01/23/2023] Open
Abstract
Opioid receptors are involved in regulating neuronal survival. Here we demonstrate that activation of the mu-opioid receptor in human neuroblastoma SH-SY5Y cells led to the phosphorylations of IkappaB kinase (IKK) and p65, denoting the stimulation of the nuclear factor-kappaB (NFkappaB) transcription factor. This response was mediated through pertussis toxin-sensitive G proteins. The mu-opioid-induced IKK phosphorylation required extracellular signal-regulated protein kinase, phosphatidylinositol 3-kinase and c-Src. Moreover, c-Jun N-terminal kinase and calmodulin-dependent kinase II also participated in the IKK activation, despite the lack of involvement of phospholipase Cbeta and protein kinase C. These data suggest that the mu-opioid receptor is capable of simulating NFkappaB signaling via the phosphorylation of IKK and p65 in human neuroblastoma SH-SY5Y cells.
Collapse
Affiliation(s)
- Andrew M F Liu
- Department of Biochemistry, Molecular Neuroscience Center, and Biotechnology Research Institute, Hong Kong University of Science and Technology, Kowloon, SAR, China
| | | |
Collapse
|
23
|
Weinberger B, Hanna N, Laskin JD, Heck DE, Gardner CR, Gerecke DR, Laskin DL. Mechanisms mediating the biologic activity of synthetic proline, glycine, and hydroxyproline polypeptides in human neutrophils. Mediators Inflamm 2005; 2005:31-8. [PMID: 15770064 PMCID: PMC1513057 DOI: 10.1155/mi.2005.31] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The accumulation of neutrophils at sites of tissue injury or
infection is mediated by chemotactic factors released as part of
the inflammatory process. Some of these factors are generated as
a direct consequence of tissue injury or infection, including
degradation fragments of connective tissue collagen and
bacterial- or viral-derived peptides containing collagen-related
structural motifs. In these studies, we examined biochemical
mechanisms mediating the biologic activity of synthetic
polypeptides consisting of repeated units of proline (Pro),
glycine (Gly), and hydroxyproline (Hyp), major amino acids found
within mammalian and bacterial collagens. We found that the
peptides were chemoattractants for neutrophils. Moreover, their
chemotactic potency was directly related to their size and
composition. Thus, the pentameric peptides (Pro-Pro-Gly)5 and
(Pro-Hyp-Gly)5 were more active in inducing chemotaxis than
the corresponding decameric peptides (Pro-Pro-Gly)10 and
(Pro-Hyp-Gly)10. In addition, the presence of Hyp in
peptides reduced chemotactic activity. The synthetic peptides
were also found to reduce neutrophil apoptosis. In contrast to
chemotaxis, this activity was independent of peptide size or
composition. The effects of the peptides on both chemotaxis and
apoptosis were blocked by inhibitors of phosphatidylinositol
3-kinase (PI3-K) and p38 mitogen-activated protein (MAP) kinase.
However, only (Pro-Pro-Gly)5 and (Pro-Pro-Gly)10 induced
expression of PI3-K and phosphorylation of p38 MAP kinase,
suggesting a potential mechanism underlying reduced chemotactic
activity of Hyp-containing peptides. Although none of the
synthetic peptides tested had any effect on intracellular calcium
mobilization, each induced nuclear binding activity of the
transcription factor NF-κB. These findings indicate that
polymeric polypeptides containing Gly-X-Y collagen-related
structural motifs promote inflammation by inducing chemotaxis and
blocking apoptosis. However, distinct calcium-independent
signaling pathways appear to be involved in these activities.
Collapse
Affiliation(s)
- Barry Weinberger
- Division of Neonatology, Department of Pediatrics, UMDNJ Robert Wood
Johnson Medical School, New Brunswick, NJ 08903, USA
- * Barry Weinberger;
| | - Nazeeh Hanna
- Division of Neonatology, Department of Pediatrics, UMDNJ Robert Wood
Johnson Medical School, New Brunswick, NJ 08903, USA
| | - Jeffrey D. Laskin
- Department of Environmental and Occupational Medicine, UMDNJ Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Diane E. Heck
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854, USA
| | - Carol R. Gardner
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854, USA
| | - Donald R. Gerecke
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854, USA
| | - Debra L. Laskin
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854, USA
| |
Collapse
|
24
|
Chen LY, Doerner A, Lehmann PF, Huang S, Zhong G, Pan ZK. A novel protein kinase C (PKCepsilon) is required for fMet-Leu-Phe-induced activation of NF-kappaB in human peripheral blood monocytes. J Biol Chem 2005; 280:22497-501. [PMID: 15809302 DOI: 10.1074/jbc.m413033200] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have reported that the chemoattractant, fMet-Leu-Phe (fMLP), induces the activation of NF-kappaB in human peripheral blood monocytes and that this requires the activity of small GTPase, RhoA (Huang, S., Chen, L.-Y., Zuraw, B. L., Ye, R. D., and Pan, Z. K. (2001) J. Biol. Chem. 276, 40977-40981). Here we showed that the novel protein kinase C isozyme, PKCepsilon, associates functionally with RhoA in fMLP-stimulated monocytes and that PKCepsilon acted as a signaling component downstream of the GTPase RhoA during fMLP-induced activation of NF-kappaB. Stimulation of monocytes with fMLP resulted in activation of both PKCepsilon and NF-kappaB. This latter activation was largely blocked by specific inhibitors of PKCepsilon by transient expression of a dominant-negative form of PKCepsilon and by PKCepsilon-specific short interfering RNA. These findings demonstrate, for the first time, that fMLP-induced activation of NF-kappaB utilizes a signaling pathway, which requires activity of PKCepsilon, and that PKCepsilon acts as a signaling component downstream of RhoA in cytokine gene transcription stimulated by a chemoattractant. The specificity of this response suggests an important role for the Rho GTPase-PKCepsilon-NF-kappaB pathway in host defense and represents a novel and potentially important mechanism through which fMLP not only attracts leukocytes but may also contribute directly to inflammation.
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Medicine, and Department of Medical Microbiology and Immunology, Medical College of Ohio, 3055 Arlington Avenue, Toledo, OH 43614, USA
| | | | | | | | | | | |
Collapse
|
25
|
Fu H, Björkman L, Janmey P, Karlsson A, Karlsson J, Movitz C, Dahlgren C. The two neutrophil members of the formylpeptide receptor family activate the NADPH-oxidase through signals that differ in sensitivity to a gelsolin derived phosphoinositide-binding peptide. BMC Cell Biol 2004; 5:50. [PMID: 15625007 PMCID: PMC545074 DOI: 10.1186/1471-2121-5-50] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2004] [Accepted: 12/29/2004] [Indexed: 11/29/2022] Open
Abstract
Background The formylpeptide receptor family members FPR and FPRL1, expressed in myeloid phagocytes, belong to the G-protein coupled seven transmembrane receptor family (GPCRs). They share a high degree of sequence similarity, particularly in the cytoplasmic domains involved in intracellular signaling. The established model of cell activation through GPCRs states that the receptors isomerize from an inactive to an active state upon ligand binding, and this receptor transformation subsequently activates the signal transducing G-protein. Accordingly, the activation of human neutrophil FPR and FPRL1 induces identical, pertussis toxin-sensitive functional responses and a transient increase in intracellular calcium is followed by a secretory response leading to mobilization of receptors from intracellular stores, as well as a release of reactive oxygen metabolites. Results We report that a cell permeable ten amino acid peptide (PBP10) derived from the phosphatidylinositol 4,5-bisphosphate (PIP2) binding region of gelsolin (an uncapper of actin filaments) blocks granule mobilization as well as secretion of oxygen radicals. The inhibitory effect of PBP10 is, however, receptor specific and affects the FPRL1-, but not the FPR-, induced cellular response. The transient rise in intracellular calcium induced by the active receptors is not affected by PBP10, suggesting that the blockage occurs in a parallel, novel signaling pathway used by FPRL1 to induce oxygen radical production and secretion. Also the FPR can activate neutrophils through a PBP10-sensitive signaling pathway, but this signal is normally blocked by the cytoskeleton. Conclusions This study demonstrates that the two very closely related chemoattractant receptors, FPR and FPRL1, use distinct signaling pathways in activation of human neutrophils. The PIP2-binding peptide PBP10 selectively inhibits FPRL1-mediated superoxide production and granule mobilization. Furthermore, the activity of this novel PBP10 sensitive pathway in neutrophils is modulated by the actin cytoskeleton network.
Collapse
Affiliation(s)
- Huamei Fu
- Department of Rheumatology and Inflammation Research, University of Göteborg, Sweden
| | - Lena Björkman
- Department of Rheumatology and Inflammation Research, University of Göteborg, Sweden
| | - Paul Janmey
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19063 USA
| | - Anna Karlsson
- Department of Rheumatology and Inflammation Research, University of Göteborg, Sweden
| | - Jennie Karlsson
- Department of Rheumatology and Inflammation Research, University of Göteborg, Sweden
| | | | - Claes Dahlgren
- Department of Rheumatology and Inflammation Research, University of Göteborg, Sweden
| |
Collapse
|
26
|
Liu AMF, Wong YH. G16-mediated activation of nuclear factor kappaB by the adenosine A1 receptor involves c-Src, protein kinase C, and ERK signaling. J Biol Chem 2004; 279:53196-204. [PMID: 15485865 DOI: 10.1074/jbc.m410196200] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The G(i)-linked adenosine A1 receptor has been shown to mediate anti-inflammatory actions, possibly via modulation of the transcription factor nuclear factor-kappaB (NFkappaB). Here we demonstrate that an adenosine A1 agonist, N(6)-cyclohexyladenosine (CHA), activated IKKalpha/beta phosphorylation through PTX-insensitive G proteins in human lymphoblastoma Reh cells. To delineate the mechanism of action, different PTX-insensitive G proteins were expressed in human embryonic kidney 293 cells. Only Galpha(16) supported the CHA-induced IKK phosphorylation and NFkappaB-driven luciferase activity in time-dependent, dose-dependent, and PTX-insensitive manners. Gbetagamma subunits also modulated IKK/NFkappaB, as indicated by the stimulatory actions of Gbeta(1)gamma(2) and the abrogation of CHA-induced response by transducin. The participation of phospholipase Cbeta, protein kinase C, and calmodulin-dependent kinase II in CHA-induced IKK/NFkappaB activation were demonstrated by employing specific inhibitors and dominant-negative mutants. Inhibition of c-Src and numerous intermediates along the extracellular signal-regulated (ERK) kinase cascade including Ras, Raf-1 kinase, and MEK1/2 abolished the CHA-induced IKK/NFkappaB activation. Although c-Jun N-terminal kinase and p38 MAPK were also activated by CHA, they were not required for the IKK/NFkappaB regulation. Similar results were obtained using Reh cells. These data suggest that the G(16)-mediated activation of IKK/NFkappaB by CHA required a complex signaling network composed of multiple intermediates.
Collapse
Affiliation(s)
- Andrew M F Liu
- Department of Biochemistry, Molecular Neuroscience Center, and Biotechnology Research Institute, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | | |
Collapse
|
27
|
Abstract
GTPase RhoA is required for fMet-Leu-Phe (fMLP)-stimulated NF-kappaB activation in human peripheral blood monocytes. Here we have investigated different members of the Rho family of GTPases Rac1, Cdc42, and RhoA in regulating the transcription factor nuclear factor-kappaB (NF-kappaB) in human peripheral blood monocytes. Stimulation of monocytes with fMLP rapidly activated Rac1, Cdc42, and RhoA and cotransfection of the monocytic THP1 cells with dominant negative forms of Rho GTPases, we found that Rac1 and RhoA, but not Cdc42, involved fMLP-stimulated kappaB reporter gene expression. These results indicate that fMLP stimulates three members of the Rho family of GTPases Rac1, Cdc42, and RhoA activity in monocytes, and that Rac1 and RhoA, but not Cdc42, is required for fMLP-induced NF-kappaB activation. Furthermore, our data also suggest that RhoA is mediated by signals independent of Rac1 in NF-kappaB activation in human peripheral blood monocytes stimulated with bacterial products.
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Microbiology and Immunology, Medical College of Ohio, Toledo, OH 43614, USA
| | | | | |
Collapse
|
28
|
Chen LY, Zuraw BL, Ye RD, Pan ZK. A Rho exchange factor mediates fMet-Leu-Phe-induced NF-kappaB activation in human peripheral blood monocytes. J Biol Chem 2003; 279:7208-12. [PMID: 14660653 DOI: 10.1074/jbc.m309542200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We reported previously that fMLP stimulates NF-kappaB activation, and this function of fMLP requires small GTPase RhoA in human peripheral blood monocytes (Huang, S., Chen, L.-Y., Zuraw, B. L., Ye, R. D., and Pan, Z. K. (2001) J. Biol. Chem. 276, 40977-40981). Here we present evidence that RhoA associates specifically with the guanine nucleotide exchange factor Lbc in human peripheral blood monocytes stimulated with fMLP and that Lbc specifically catalyzes the guanine nucleotide exchange activity of RhoA in human peripheral blood monocytes. Cotransfection of the monocytic THP1 cells with lbc with a kappaB promoter reporter plasmid results in a marked increase in NF-kappaB-mediated reporter gene expression. Finally, Lbc-enhanced NF-kappaB activation is inhibited by a RhoA inhibitor, C3 transferase from Clostridium botulinum. A dominant-negative form of RhoA (T19N) also inhibited Lbc-enhanced reporter gene expression in a kappaB-dependent manner. These results indicate that guanine nucleotide exchange factor Lbc is a novel signal transducer for RhoA-mediated NF-kappaB activation in human peripheral blood monocytes stimulated with bacterial products.
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Microbiology and Immunology, Medical College of Ohio, Toledo, Ohio 43614, USA
| | | | | | | |
Collapse
|
29
|
Abstract
Phospholipase A(2) plays a key role in phagocytic cell functions. By screening a synthetic hexapeptide combinatorial library, we identified 24 novel peptides based on their ability to stimulate arachidonic acid release associated with cytosolic phospholipase A(2) activity in differentiated HL60 cells. The identified peptides, that contain the consensus sequence (K/R/M)KYY(P/V/Y)M, also induce intracellular calcium release in a pertussis toxin-sensitive manner showing specific action on phagocytic leukocytes, but not on other cells. Functionally, the peptides stimulate superoxide generation and chemotactic migration in human neutrophils and monocytes. Four of the tested active peptides were ligands for formyl peptide receptor like 1. Among these, two peptides with the consensus sequence (R/M)KYYYM can induce intracellular calcium release in undifferentiated HL60 cells that do not express formyl peptide receptor like 1, indicating usage of other receptor(s). A study of intracellular signaling in differentiated HL60 cells induced by the peptides has revealed that four of the novel peptides can induce extracellular signal-regulated protein kinase activation via shared and distinct signaling pathways, based on their dependence of phospatidylinositol-3-kinase, protein kinase C, and MEK. These peptides provide previously unavailable tools for study of differential signaling in leukocytes.
Collapse
Affiliation(s)
- Yoe-Sik Bae
- Department of Biochemistry, College of Medicine, Medical Research Center for Cancer Molecular Therapy, Dong-A University, Busan 02-714, South Korea
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Bae YS, Park JC, He R, Ye RD, Kwak JY, Suh PG, Ho Ryu S. Differential signaling of formyl peptide receptor-like 1 by Trp-Lys-Tyr-Met-Val-Met-CONH2 or lipoxin A4 in human neutrophils. Mol Pharmacol 2003; 64:721-30. [PMID: 12920210 DOI: 10.1124/mol.64.3.721] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Classical chemoattractant receptors are of fundamental importance to immune responses. The two major roles of such receptors are the modulation of chemotaxis and the generation of reactive oxygen species. The formyl peptide receptor-like 1 (FPRL1) can be stimulated by two different ligands, Trp-Lys-Tyr-Met-Val-Met-CONH2 (WKYMVM) and lipoxin A4 (LXA4). Although leukocyte chemotaxis mediated by activated FPRL1 has been reported, the role of FPRL1 in superoxide generation remains to be studied. In this study, we examined the effect of WKYMVM or LXA4 on chemotactic migration and superoxide generation in human neutrophils. WKYMVM and LXA4 stimulated neutrophil chemotaxis via tyrosine phosphorylation events. In terms of reactive oxygen species generation, WKYMVM but not LXA4 stimulated superoxide generation in neutrophils. To understand this difference on superoxide generation via the same receptor, FPRL1, we compared the signaling pathways downstream of FPRL1 by the two different ligands. At first, we confirmed that both WKYMVM and LXA4 caused intracellular calcium ([Ca2+]i) increase in a pertussis toxin-sensitive manner and that these ligands competitively inhibited each other with respect to [Ca2+]i increase in neutrophils. This result suggests that WKYMVM and LXA4 share the same receptor, FPRL1. By investigating cellular signaling by WKYMVM and LXA4, we found that WKYMVM but not LXA4 induced extracellular signal-regulated protein kinases (ERKs), c-Jun NH2-terminal kinase, and phospholipase A2 (PLA2) activation. We also found that ERK-mediated cytosolic PLA2 activity is essential for superoxide generation. These results indicate that the activation of FPRL1 by the two different ligands can induce differential cellular signaling and unique functional consequences in human neutrophils.
Collapse
Affiliation(s)
- Yoe-Sik Bae
- Division of Molecular and Life Sciences, Pohang University of Science and Technology, San 31, Hyojadong, Pohang, 790-784, Korea.
| | | | | | | | | | | | | |
Collapse
|
31
|
Yang M, Zhang H, Voyno-Yasenetskaya T, Ye RD. Requirement of Gbetagamma and c-Src in D2 dopamine receptor-mediated nuclear factor-kappaB activation. Mol Pharmacol 2003; 64:447-55. [PMID: 12869650 DOI: 10.1124/mol.64.2.447] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The D2 dopamine receptor (D2R) was examined for its ability to mediate nuclear factor-kappaB (NF-kappaB) activation through G proteins. Stimulation of D2R-transfected HeLa cells with its agonist quinpirole induced the expression of a NF-kappaB luciferase reporter and formation of NF-kappaB-DNA complex. This response was blocked by pertussis toxin, and by the Gbetagamma scavengers transducin and beta-adrenergic receptor kinase 1 carboxyl-terminal fragment. Unlike Gi-coupled chemoattractant receptors, D2R activated NF-kappaB without an increase in phospholipase C-beta activity, and the response was only slightly affected by the phosphoinositide 3-kinase inhibitor 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002). In contrast, treatment with genistein and 4-amino-1-tert-butyl-3-(p-methylphenyl)pyrazolo[3,4-d] pyrimidine abolished the induced NF-kappaB activation, suggesting involvement of protein tyrosine kinases. Activation of D2R led to phosphorylation of c-Src at Tyr-418, and expression of a kinase-deficient c-Src inhibited D2R-mediated NF-kappaB activation. The D2R-mediated NF-kappaB activation was not dependent on epidermal growth factor (EGF) receptor transactivation since 4-(3'-chloroanilino)-6,7-dimethoxyquinazoline (AG1478), an EGF receptor-selective tyrphostin used at 1 microM, blocked EGF-induced NF-kappaB activation but not the quinpirole-induced response. In addition, the D2R-mediated NF-kappaB activation was enhanced by over-expression of beta-arrestin 1. These results suggest that D2R-mediated NF-kappaB activation requires Gbetagamma and c-Src, and possibly involves beta-arrestin 1.
Collapse
Affiliation(s)
- Ming Yang
- Department of Pharmacology, M/C 868, University of Illinois at Chicago, 835 S. Wolcott Avenue, Chicago, IL 60612, USA
| | | | | | | |
Collapse
|
32
|
Chen LY, Zuraw BL, Zhao M, Liu FT, Huang S, Pan ZK. Involvement of protein tyrosine kinase in Toll-like receptor 4-mediated NF-kappa B activation in human peripheral blood monocytes. Am J Physiol Lung Cell Mol Physiol 2003; 284:L607-13. [PMID: 12495941 DOI: 10.1152/ajplung.00116.2002] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Bacterial lipopolysaccharide (LPS) is a powerful activator of the innate immune system. Exposure to LPS induces an inflammatory reaction in the lung mediated primarily by human blood monocytes and alveolar macrophages, which release an array of inflammatory chemokines and cytokines including IL-8, TNF-alpha, IL-1beta, and IL-6. The signaling mechanisms utilized by LPS to stimulate the release of cytokines and chemokines are still incompletely understood. Pretreatment with the protein tyrosine kinase-specific inhibitors genistein and herbimycin A effectively blocked LPS-induced NF-kappaB activation as well as IL-8 gene expression in human peripheral blood monocytes. However, when genistein was added 2 min after the addition of LPS, no inhibition was observed. Utilizing a coimmunoprecipitation assay, we further showed that LPS-stimulated tyrosine phosphorylation of Toll-like receptor 4 (TLR4) may be involved in downstream signaling events induced by LPS. These findings provide evidence that LPS-induced NF-kappaB activation and IL-8 gene expression use a signaling pathway requiring protein tyrosine kinase and that such regulation may occur through tyrosine phosphorylation of TLR4.
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla 92037, California 92121, USA
| | | | | | | | | | | |
Collapse
|
33
|
Pereira A, del Valle Onorato M, Sanz C. DDAVP enhances the ability of blood monocytes to form rosettes with activated platelets by increasing the expression of P-selectin sialylated ligands on the monocyte surface. Br J Haematol 2003; 120:814-20. [PMID: 12614215 DOI: 10.1046/j.1365-2141.2003.04180.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The mechanism through which DDAVP (1-deamino-8-d-arginine vasopressin) promotes blood coagulation is not completely understood. As blood monocytes have been identified as a target for DDAVP, we investigated whether this drug increased monocyte adhesion to activated platelets, which would result in the close intercellular contact that is necessary for a juxtacrine effect on platelets and/or endothelium at sites of vascular injury. Monolayers of non-confluent monocytes adhered to glass slides were incubated with thrombin-activated, formaldehyde-fixed platelets before and after the adherent monocytes were stimulated with DDAVP or n-formyl-methyl-leucyl-phenylalanine (fMLP). The number of platelets involved in rosettes with monocytes was quantified, and the effect of DDAVP or fMLP on the monocyte surface expression of P-selectin ligands and CD11b/CD18 was assessed. DDAVP or fMLP increased the number of activated platelets involved in rosettes with monocytes by 2.8- and 4.9-fold respectively. EDTA and inhibitors of the P-selectin/counter-receptor interaction decreased the platelet numbers in rosettes by 80-90%, whereas inhibitors of the integrin-mediated adhesion reduced rosettes by 40-50%. Blocking the P-selectin glycoprotein ligand-1 (PSGL-1) with the monoclonal antibody, Pl-1, decreased the platelet numbers in rosettes by only 50%. In contrast, surface expression of the sialylated ligands of P-selectin and, to a lesser extent, of CD11b/CD18 increased upon monocyte activation with DDAVP or fMLP, whereas it decreased slightly with PSGL-1. These results indicate that DDAVP enhanced the ability of blood monocytes to bind activated platelets, mainly by increasing the expression of P-selectin sialylated ligands on the monocyte surface. A similar effect was achieved with fMLP.
Collapse
Affiliation(s)
- Arturo Pereira
- Service of Haemotherapy, Haemostasis, and the Blood Bank, Hospital Clinic, Barcelona, Spain.
| | | | | |
Collapse
|
34
|
Chen LY, Zuraw BL, Liu FT, Huang S, Pan ZK. IL-1 receptor-associated kinase and low molecular weight GTPase RhoA signal molecules are required for bacterial lipopolysaccharide-induced cytokine gene transcription. J Immunol 2002; 169:3934-9. [PMID: 12244193 DOI: 10.4049/jimmunol.169.7.3934] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Proinflammatory cytokines such as IL-1, TNF, IL-6, and IL-8 are produced by leukocytes in response to bacteria or bacterial components. A great deal has been learned during the past few years about the synthesis and release of proinflammatory cytokines by leukocytes; however, relatively little is known about the intracellular events that lead to leukocyte proinflammatory cytokine gene transcription. This study examined the signal transduction pathway of IL-8 induction by bacterial LPS. Stimulation of monocytes with LPS rapidly activated RhoA, and pretreatment of monocytes with a RhoA inhibitor, C3 transferase exoenzyme, effectively blocked LPS-induced IL-8 gene expression. Overexpression of dominant negative RhoA (T19N) or IL-1R-associated kinase completely inhibited LPS-stimulated reporter gene expression. Induction of IL-8 was also inhibited by dominant negative IkappaB kinase and myeloid differentiation protein (MyD88). These results indicate that RhoA and IL-1R-associated kinase are novel signal transducers for LPS-induced Toll-like receptor 4-mediated proinflammatory cytokine synthesis in human monocytes.
Collapse
MESH Headings
- Adaptor Proteins, Signal Transducing
- Antigens, Differentiation/genetics
- Antigens, Differentiation/physiology
- Cell Line
- Cells, Cultured
- Cytokines/genetics
- Cytokines/metabolism
- Drosophila Proteins
- Enzyme Activation/immunology
- Gene Expression Regulation, Enzymologic/immunology
- Humans
- Interleukin-1 Receptor-Associated Kinases
- Lipopolysaccharides/pharmacology
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/physiology
- Molecular Weight
- Monocytes/enzymology
- Monocytes/immunology
- Myeloid Differentiation Factor 88
- Protein Kinases/genetics
- Protein Kinases/physiology
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/physiology
- Receptors, Immunologic/genetics
- Receptors, Immunologic/physiology
- Receptors, Interleukin-1/metabolism
- Signal Transduction/genetics
- Signal Transduction/immunology
- Toll-Like Receptor 4
- Toll-Like Receptors
- Transcription, Genetic/immunology
- Transfection
- Tumor Cells, Cultured
- rhoA GTP-Binding Protein/genetics
- rhoA GTP-Binding Protein/metabolism
- rhoA GTP-Binding Protein/physiology
Collapse
Affiliation(s)
- Ling-Yu Chen
- Department of Molecular and Experimental Medicine and Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | | | | | | |
Collapse
|
35
|
Chen X, Howard OMZ, Yang X, Wang L, Oppenheim JJ, Krakauer T. Effects of Shuanghuanglian and Qingkailing, two multi-components of traditional Chinese medicinal preparations, on human leukocyte function. Life Sci 2002; 70:2897-913. [PMID: 12269401 DOI: 10.1016/s0024-3205(02)01541-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Qingkailing (QKL) and Shuanghuanglian (SHHL) are two commonly used Chinese herbal preparations with reported antiinflammatory activity. The effects of these two preparations on the capacity of staphylococcal toxic shock syndrome toxin 1 (TSST-1) to stimulate the production of cytokines (IL-1beta, IL-6, TNF-alpha, IFN-gamma) and chemokines (MIP-1alpha, MIP-1beta and MCP-1) by peripheral blood mononuclear cell (PBMC) was tested. We also evaluated their effect on LPS-stimulated NF-kappaB transcriptional activity in a THP-1 cell line, and on human monocyte chemotactic response to chemoattractants. Non-cytotoxic concentrations of QKL (0.1 to approximately 2%) and SHHL (6 to approximately 120 microg) significantly inhibited production of cytokines and chemokines in a dose-dependent manner (P < 0.05). Both, QKL at 1:100 and SHHL at 60 microg/ml, markedly inhibited RANTES, MIP-1alpha, SDF-1alpha and fMLP induced human monocyte migration (P < 0.05 or 0.01). QKL (1%) did not inhibit monocyte chemotaxis induced by super-or sub-optimal concentrations of fMLP (10(-5), 10(-6) and 10(-10) M), but only inhibited chemotaxis induced by optimal concentrations of fMLP at 10(-7), 10(-8) and 10(-9) M. QKL (0.1% or 1%) and SHHL (6 or 60 microg/ml) markedly inhibited LPS-induced NF-kappaB activity in THP-1 cells. The results suggested that the pharmacological basis for the antiinflammatory effects of QKL and SHHL is the result of suppression of NF-kappaB regulated gene transcription, leading to suppressed production of proinflammatory cytokine and chemokine. Interference with leukocyte chemotaxis also contributes to the antiinflammatory and immunomodulating effects of these medicinals. Identification of the responsible components in these two herbal preparations may yield compounds suitable for structural modification into potent novel drugs.
Collapse
Affiliation(s)
- Xin Chen
- Laboratory of Molecular Immunoregulation, Center for Cancer Research, National Cancer Institute-Frederick, Fort Detrick, MD, 21702-1201, USA.
| | | | | | | | | | | |
Collapse
|
36
|
Abstract
UNLABELLED Humic acid (HA), a fluorescent allomelanin, has been implicated as an etiological agent of Blackfoot disease (BFD), a peripheral vascular disease prevailing in the southwest of Taiwan. Clinical and pathological studies reveal that it is similar to atherosclerosis. In this report, the effect of HA on human neutrophils is studied because prolonged and enhanced activation of neutrophils adhered on endothelium may damage the endothelium and initiate the process of thrombosis and vasculitis. METHODS Neutrophils, treated with various concentrations of HA, were added to culture plates, cultured human umbilical vein endothelial cells (HUVECs), or human umbilical vein endothelium tissue culture for 15 or 30 min. The adhesion of neutrophils was measured qualitatively and quantitatively. The mechanism of neutrophil activation was studied with free radical production and various kinase measurements and their activities' assays. RESULTS HA was shown to enhance, in a dose-dependent manner, the adhesion of neutrophils on the culture plates, cultured human umbilical vein endothelial cells, and human umbilical vein endothelium tissue culture. The adhesion-enhancing ability of HA is elicited through activation of ERK, P38 mitogen-activated kinase (P38MAPK), and phosphoinositide 3 kinase (PI3K) in neutrophils. HA also induces the NF-kappaB activation in neutrophils. CONCLUSION HA treatment markedly enhanced adhesion and superoxide radical production of neutrophils, the characteristics of activated neutrophils; and all these stimulation effects were blocked by several kinase inhibitors, reflecting the involvement of the ERK, P38MAPK, and PI3K on the activation of neutrophils. The induction of NF-kappaB implied that the consequence of neutrophil activation by HA were similar to other stimulants. The prolonged neutrophil activation will further damage endothelium cell and cause thrombosis, vaculitis, as well as arteriosclerosis. This may partially explain why HA consumption will cause BFD.
Collapse
Affiliation(s)
- Chong-Hua Chen
- Graduate Institute of Biochemistry and Molecular Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | | | | | | | | | | |
Collapse
|
37
|
Chen BC, Wu WT, Ho FM, Lin WW. Inhibition of interleukin-1beta -induced NF-kappa B activation by calcium/calmodulin-dependent protein kinase kinase occurs through Akt activation associated with interleukin-1 receptor-associated kinase phosphorylation and uncoupling of MyD88. J Biol Chem 2002; 277:24169-79. [PMID: 11976320 DOI: 10.1074/jbc.m106014200] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Calcium/calmodulin-dependent protein kinase kinase (CaMKK) and Akt are two multifunctional kinases involved in many cellular responses. Although Akt and Ca(2+) signals have been implicated in NF-kappaB activation in response to certain stimuli, these results are still controversial, and the mechanism(s) involved remains unknown. In this study, we show the roles that CaMKK and Akt play in regulating interleukin-1beta (IL-1beta)-induced NF-kappaB signaling. In human embryonic kidney 293 cells, IL-1beta induces IkappaB kinase beta (IKKbeta) activation, IkappaBalpha degradation, NF-kappaB transactivation, and weak Akt activation. A CaMKK inhibitor (KN-93) and phosphatidylinositol 3-kinase inhibitors (wortmannin and LY294002) do not inhibit IL-1beta-induced NF-kappaB activation. However, IL-1beta-induced NF-kappaB activity is attenuated by increased intracellular calcium in response to ionomycin, UTP, or thapsigargin or by overexpression of CaMKKc and/or Akt. Ionomycin and CaMKKc overexpression increases Akt phosphorylation on Thr(308) and enzyme activity. Under these conditions or upon overexpression of wild type Akt, IL-1beta-induced IKKbeta activity is diminished. Furthermore, a dominant negative mutant of Akt abolishes IKKbeta inhibition by CaMKKc and ionomycin, suggesting that Akt acts as a mediator of CaMKK signaling to inhibit IL-1beta-induced IKK activity at an upstream target site. We have also identified a novel interaction between CaMKK-stimulated Akt and interleukin-1 receptor-associated kinase 1 (IRAK1), which plays a key role in IL-1beta-induced NF-kappaB activation. CaMKKc and Akt overexpression decreases IRAK1-mediated NF-kappaB activity and its association with MyD88 in response to IL-1beta stimulation. Furthermore, CaMKKc and Akt overexpression increases IRAK1 phosphorylation at Thr(100), and point mutation of this site abrogates the inhibitory effect of Akt on IRAK1-mediated NF-kappaB activation. Taken together, these results indicate a novel regulatory mechanism for IL-1beta signaling and suggest that CaMKK-dependent Akt activation inhibits IL-1beta-induced NF-kappaB activation through interference with the coupling of IRAK1 to MyD88.
Collapse
Affiliation(s)
- Bing-Chang Chen
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | | | | | | |
Collapse
|
38
|
Ahamed J, Ali H. Distinct roles of receptor phosphorylation, G protein usage, and mitogen-activated protein kinase activation on platelet activating factor-induced leukotriene C(4) generation and chemokine production. J Biol Chem 2002; 277:22685-91. [PMID: 11934880 DOI: 10.1074/jbc.m110210200] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Platelet activating factor (PAF) interacts with cell surface G protein-coupled receptors on leukocytes to induce degranulation, leukotriene C(4) (LTC(4)) generation, and chemokine CCL2 production. Using a basophilic leukemia RBL-2H3 cell line expressing wild-type PAF receptor (PAFR) and a phosphorylation-deficient mutant (mPAFR), we have previously demonstrated that receptor phosphorylation mediates desensitization of PAF-induced degranulation. Here, we sought to determine the role of receptor phosphorylation on PAF-induced LTC(4) generation and CCL2 production. We found that PAF caused a significantly enhanced LTC(4) generation in cells expressing mPAFR when compared with PAFR cells. In contrast, PAF-induced CCL2 production was greatly reduced in mPAFR cells. Pertussis toxin and U0126, which inhibit G(i) and p44/42 mitogen-activated protein kinase (ERK) activation, respectively, caused very little inhibition of PAF-induced CCL2 production (approximately 20% inhibition). In contrast, these inhibitors almost completely blocked both PAF-induced ERK phosphorylation and LTC(4) generation in PAFR cells. However, in mPAFR cells pertussis toxin only partially inhibited PAF-induced ERK phosphorylation. A Ca(2+)/calmodulin inhibitor had no effect on PAF-induced ERK phosphorylation in PAFR cells but completely blocked the response in mPAFR cells. These data demonstrate that receptor phosphorylation, which serves to desensitize PAF-induced LTC(4) generation, is required for chemokine CCL2 production. They also indicate a previously unrecognized selectivity in G protein usage and ERK activation for PAF-induced responses. Whereas PAF-induced CCL2 production is, in large part, mediated independently of G(i) activation or ERK phosphorylation, LTC(4) generation requires ERK phosphorylation, which is mediated by different G proteins depending on the phosphorylation status of the receptor.
Collapse
Affiliation(s)
- Jasimuddin Ahamed
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, Pennsylvania 19104, USA
| | | |
Collapse
|
39
|
Chen X, Mellon RD, Yang L, Dong H, Oppenheim JJ, Howard OMZ. Regulatory effects of deoxycholic acid, a component of the anti-inflammatory traditional Chinese medicine Niuhuang, on human leukocyte response to chemoattractants. Biochem Pharmacol 2002; 63:533-41. [PMID: 11853704 DOI: 10.1016/s0006-2952(01)00917-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Niuhuang is a commonly used Chinese traditional medicine with immunoregulatory and anti-inflammatory properties. Deoxycholic acid (DCA) is a major active constituent of Niuhuang. The reaction of human leukocytes to chemoattractants is an important part of the host immune response and also plays a crucial role in the development of inflammation. We, therefore, investigated the in vitro effects of DCA on human monocyte and neutrophil responses to classic chemoattractants [fMet-Leu-Phe (fMLP), complement fraction 5a (C5a)], CC chemokine [monocyte chemoattractant protein-1 (MCP-1/CCL2)], and/or CXC chemokines [stromal cell-derived factor-1 (SDF-1alpha/CXCL12), interleukin-8 (IL-8/CXCL8)]. The results showed that DCA significantly inhibited fMLP-induced monocyte and neutrophil chemotaxis and calcium mobilization, and also blocked the binding of [3H]fMLP and anti-formyl peptide receptor (FPR) monoclonal antibodies (mAb) to the cells. The inhibitory effects of DCA on calcium mobilization and anti-FPR-mAb binding to the receptor could be abrogated by washing DCA out of the cell suspension, suggesting that DCA blocked fMLP receptors via a steric hindrance mechanism, not via receptor internalization. DCA had no significant inhibitory effects on MCP-1-, SDF-1alpha-, or C5a-induced monocyte function, or C5a- or IL-8-induced neutrophil function. Taken together, our experimental results suggest that blockade of fMLP receptors may contribute to the anti-inflammatory effects of traditional medicine containing DCA.
Collapse
MESH Headings
- Anti-Inflammatory Agents/pharmacology
- Antibodies/immunology
- Calcium/metabolism
- Cell Movement/drug effects
- Cell Respiration/drug effects
- Chemokines/pharmacology
- Chemotactic Factors/pharmacology
- Deoxycholic Acid/pharmacology
- Drug Interactions
- Humans
- In Vitro Techniques
- Interleukin-8/metabolism
- Leukocytes/drug effects
- Leukocytes/physiology
- Medicine, Chinese Traditional
- N-Formylmethionine Leucyl-Phenylalanine/metabolism
- Receptors, Formyl Peptide
- Receptors, Immunologic/immunology
- Receptors, Immunologic/metabolism
- Receptors, Interleukin-8A/immunology
- Receptors, Interleukin-8A/metabolism
- Receptors, Interleukin-8B/immunology
- Receptors, Interleukin-8B/metabolism
- Receptors, Peptide/immunology
- Receptors, Peptide/metabolism
- Tritium
Collapse
Affiliation(s)
- Xin Chen
- The Laboratory of Molecular Immunoregulation, Center for Cancer Research, National Cancer Institute-Frederick, Bldg. 560, Rm. 31-19, Frederick, MD 21702-1201, USA
| | | | | | | | | | | |
Collapse
|
40
|
Sodhi A, Biswas SK. fMLP‐induced in vitro nitric oxide production and its regulation in murine peritoneal macrophages. J Leukoc Biol 2002. [DOI: 10.1189/jlb.71.2.262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Ajit Sodhi
- School of Biotechnology, Banaras Hindu University, Varanasi, India
| | - Subhra K. Biswas
- School of Biotechnology, Banaras Hindu University, Varanasi, India
| |
Collapse
|
41
|
Abstract
Leukocytes accumulate at sites of inflammation and immunological reaction in response to locally existing chemotactic mediators. N-formyl peptides, such as fMet-Leu-Phe (fMLF), are some of the first identified and most potent chemoattractants for phagocytic leukocytes. In addition to the bacterial peptide fMLF and the putative endogenously produced formylated peptides, a number of novel peptide agonists have recently been identified that selectively activate the high-affinity fMLF receptor FPR and/or its low-affinity variant FPRL1, both of which belong to the seven-transmembrane (STM), G protein-coupled receptor (GPCR) superfamily. These agonists include peptide domains derived from the envelope proteins of human immunodeficiency virus type 1 (HIV-1) and at least three amyloidogenic polypeptides, the human acute phase protein serum amyloid A, the 42 amino acid form of beta amyloid peptide and a 21 amino acid fragment of human prion. Furthermore, a cleavage fragment of neutrophil granule-derived bactericidal cathelicidin, LL-37, is also a chemotactic agonist for FPRL1. Activation of formyl peptide receptors results in increased cell migration, phagocytosis, release of proinflammatory mediators, and the signaling cascade culminates in heterologous desensitization of other STM receptors including chemokine receptors CCR5 and CXCR4, two coreceptors for HIV-1. Thus, by interacting with a variety of exogenous and host-derived agonists, formyl peptide receptors may play important roles in proinflammatory and immunological diseases and constitute a novel group of pharmacological targets.
Collapse
Affiliation(s)
- Yingying Le
- Laboratory of Molecular Immunoregulation, Center for Cancer Research, National Cancer Institute at Frederick, MD 21702, USA.
| | | | | | | | | | | | | |
Collapse
|
42
|
Affiliation(s)
- Richard D. Ye
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois
| |
Collapse
|
43
|
Yum HK, Arcaroli J, Kupfner J, Shenkar R, Penninger JM, Sasaki T, Yang KY, Park JS, Abraham E. Involvement of phosphoinositide 3-kinases in neutrophil activation and the development of acute lung injury. J Immunol 2001; 167:6601-8. [PMID: 11714830 DOI: 10.4049/jimmunol.167.11.6601] [Citation(s) in RCA: 167] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Activated neutrophils contribute to the development and severity of acute lung injury (ALI). Phosphoinositide 3-kinases (PI3-K) and the downstream serine/threonine kinase Akt/protein kinase B have a central role in modulating neutrophil function, including respiratory burst, chemotaxis, and apoptosis. In the present study, we found that exposure of neutrophils to endotoxin resulted in phosphorylation of Akt, activation of NF-kappaB, and expression of the proinflammatory cytokines IL-1beta and TNF-alpha through PI3-K-dependent pathways. In vivo, endotoxin administration to mice resulted in activation of PI3-K and Akt in neutrophils that accumulated in the lungs. The severity of endotoxemia-induced ALI was significantly diminished in mice lacking the p110gamma catalytic subunit of PI3-K. In PI3-Kgamma(-/-) mice, lung edema, neutrophil recruitment, nuclear translocation of NF-kappaB, and pulmonary levels of IL-1beta and TNF-alpha were significantly lower after endotoxemia as compared with PI3-Kgamma(+/+) controls. Among neutrophils that did accumulate in the lungs of the PI3-Kgamma(-/-) mice after endotoxin administration, activation of NF-kappaB and expression of proinflammatory cytokines was diminished compared with levels present in lung neutrophils from PI3-Kgamma(+/+) mice. These results show that PI3-K, and particularly PI3-Kgamma, occupies a central position in regulating endotoxin-induced neutrophil activation, including that involved in ALI.
Collapse
Affiliation(s)
- H K Yum
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Huang S, Chen LY, Zuraw BL, Ye RD, Pan ZK. Chemoattractant-stimulated NF-kappaB activation is dependent on the low molecular weight GTPase RhoA. J Biol Chem 2001; 276:40977-81. [PMID: 11533055 DOI: 10.1074/jbc.m105242200] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chemoattractants bind to seven transmembrane-spanning, G-protein-coupled receptors on monocytes and neutrophils and induce a variety of functional responses, including activation of the transcription factor NF-kappaB. The signaling mechanisms utilized by chemoattractants to activate NF-kappaB in human peripheral blood monocytes are poorly defined. We previously demonstrated that fMet-Leu-Phe (fMLP) stimulates NF-kappaB activation, and this function of fMLP requires phosphatidylinositol 3-kinase (PI3K). Here we present evidence that fMLP activates RhoA and that fMLP-induced NF-kappaB activation requires this small GTPase. Stimulation of monocytes with fMLP rapidly activated RhoA as well as NF-kappaB, and their activation was markedly reduced by pertussis toxin treatment. Pretreatment of monocyte with a RhoA inhibitor, C3 transferase from Clostridium botulinum, effectively blocked fMLP-induced NF-kappaB activation as well as interleukin-1beta gene expression. A dominant negative form of RhoA (T19N) also inhibited fMLP-stimulated reporter gene expression in a kappaB-dependent manner. Cotransfection of the monocytic THP1 cells with a constitutively active form of RhoA (Q63L) with the promoter reporter plasmid results in a marked increase in NF-kappaB-mediated reporter gene expression. Furthermore, the PI3K inhibitors wortmannin and LY294002 block RhoA activation induced by fMLP. These results demonstrate that low molecular weight GTPase RhoA is a novel signal transducer for fMLP-induced NF-kappaB activation and Galpha(i) or Galpha(o) class of heterotrimeric G proteins likely mediate RhoA activation via PI3K in human peripheral blood monocytes.
Collapse
Affiliation(s)
- S Huang
- Department of Molecular and Experimental Medicine, Department of Immunology, The Scripps Research Institute, La Jolla, California 92037, USA
| | | | | | | | | |
Collapse
|
45
|
Chen S, Bacon KB, Garcia G, Liao R, Pan ZK, Sullivan SK, Nakano H, Matsuzawa A, Brinkmann V, Feng L. FTY720, a novel transplantation drug, modulates lymphocyte migratory responses to chemokines. Transplant Proc 2001; 33:3057-63. [PMID: 11750317 DOI: 10.1016/s0041-1345(01)02306-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- S Chen
- Department of Immunology, The Scripps Research Institute, La Jolla, California, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
García‐García E, Sánchez‐Mejorada G, Rosales C. Phosphatidylinositol 3‐kinase and ERK are required for NF‐κB activation but not for phagocytosis. J Leukoc Biol 2001. [DOI: 10.1189/jlb.70.4.649] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Erick García‐García
- Immunology Department, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City
| | - Gabriela Sánchez‐Mejorada
- Immunology Department, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City
| | - Carlos Rosales
- Immunology Department, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City
| |
Collapse
|
47
|
Abstract
Superoxide is the most important armory on the primary defense line of monocytes against invading pathogens, and the identification of new stimuli and the characterization of the regulatory mechanism of superoxide generation are of paramount importance. In this study, we identified 3 novel peptides by screening a synthetic hexapeptide combinatorial library and modification of 1 of the peptides. The isolated peptides that can induce superoxide generation in human monocytes are His-Phe-Tyr-Leu-Pro-Met-CONH(2) (HFYLPM), Met-Phe-Tyr-Leu-Pro-Met-CONH(2) (MFYLPM), and His-Phe-Tyr-Leu-Pro-D-Met-CONH(2) (HFYLPm). All 3 peptides also caused intracellular calcium ([Ca(++)](i)) rise. We tested the specificities of the peptides on cells of different origin by looking at [Ca(++)](i) rise. All 3 peptides acted specifically on leukocytes and not on nonimmune cells. Among leukocytes, HL60 and Jurkat T cells were stimulated specifically by MFYLPM or HFYLPM, respectively. As a physiologic characteristic of the peptides, we observed that all 3 peptides induced chemotactic migration of monocytes. Studying receptor specificity, we concluded that the 3 peptides might act on some shared and some distinct receptor(s) on leukocytes. Studying intracellular signaling set in motion by the peptides revealed that HFYLPM, but not MFYLPM or HFYLPm, induced chemotaxis via phosphatidylinositol-3 kinase and protein kinase C. Because HFYLPM, MFYLPM, and HFYLPm not only exhibit different specificities depending on cell type and status of differentiation but also stimulate cells via distinct receptors and signaling, the 3 novel peptides might be useful tools to study leukocyte activation.
Collapse
Affiliation(s)
- Y S Bae
- Division of Molecular and Life Sciences, Pohang University of Science and Technology, Korea
| | | | | | | | | | | |
Collapse
|
48
|
Ceponis PJ, Botelho F, Richards CD, McKay DM. Interleukins 4 and 13 increase intestinal epithelial permeability by a phosphatidylinositol 3-kinase pathway. Lack of evidence for STAT 6 involvement. J Biol Chem 2000; 275:29132-7. [PMID: 10871612 DOI: 10.1074/jbc.m003516200] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Interleukins 4 and 13 can affect their target cells by activation of signal transducer and activator of transcription 6 (STAT 6) or phosphatidylinositol 3-kinase (PI3K). We examined the signal transduction events involved in IL-4 and IL-13 regulation of epithelial paracellular permeability using T84 cells, a model human colonic epithelium. T84 cells treated with IL-4 or IL-13 displayed virtually identical dose- and time-dependent STAT 6 activation as assessed by electrophoretic mobility shift assay (EMSA) and decreases in transepithelial resistance (TER). STAT 6 DNA binding activity was maximal in nuclear extracts 30 min after exposure to IL-4 or IL-13, and TER was maximally reduced by 24 h post-treatment. Pretreatment of epithelia with transcription factor decoys (phosphorothioated DNA oligonucleotides containing the STAT 6 binding site) dramatically reduced STAT 6 activation as detected by EMSA, but did not attenuate the TER reduction by IL-4 or IL-13. In contrast, although the PI3K inhibitors wortmannin and LY294002 did not affect IL-4 or IL-13 STAT 6 activation, they significantly inhibited the ability of either cytokine to lower TER. Thus, we provide evidence for PI3K as the major proximal signaling event in IL-4 and IL-13 regulation of TER and speculate that pharmacological targeting of enterocytic PI3K activity may represent a means to manipulate epithelial permeability.
Collapse
Affiliation(s)
- P J Ceponis
- Intestinal Disease Research Programme and Infection and Immunity Programme, McMaster University, Hamilton, Ontario L8N 3Z5, Canada
| | | | | | | |
Collapse
|
49
|
Condliffe AM, Cadwallader KA, Walker TR, Rintoul RC, Cowburn AS, Chilvers ER. Phosphoinositide 3-kinase: a critical signalling event in pulmonary cells. Respir Res 2000; 1:24-9. [PMID: 11667961 PMCID: PMC59538 DOI: 10.1186/rr8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2000] [Revised: 05/23/2000] [Accepted: 05/23/2000] [Indexed: 11/10/2022] Open
Abstract
Phosphoinositide 3-kinases (PI-3Ks) are enzymes that generate lipid second messenger molecules, resulting in the activation of multiple intracellular signalling cascades. These events regulate a broad array of cellular responses including survival, activation, differentiation and proliferation and are now recognised to have a key role in a number of physiological and pathophysiological processes in the lung. PI-3Ks contribute to the pathogenesis of asthma by influencing the proliferation of airways smooth muscle and the recruitment of eosinophils, and affect the balance between the harmful and protective responses in pulmonary inflammation and infection by the modulation of granulocyte recruitment, activation and apoptosis. In addition they also seem to exert a critical influence on the malignant phenotype of small cell lung cancer. PI-3K isoforms and their downstream targets thus provide novel therapeutic targets for intervention in a broad spectrum of respiratory diseases.
Collapse
Affiliation(s)
- Alison M Condliffe
- University of Cambridge School of Clinical Medicine, Addenbrooke's and Papworth Hospitals, Cambridge, UK
| | - Karen A Cadwallader
- University of Cambridge School of Clinical Medicine, Addenbrooke's and Papworth Hospitals, Cambridge, UK
| | | | | | - Andrew S Cowburn
- University of Cambridge School of Clinical Medicine, Addenbrooke's and Papworth Hospitals, Cambridge, UK
| | - Edwin R Chilvers
- University of Cambridge School of Clinical Medicine, Addenbrooke's and Papworth Hospitals, Cambridge, UK
| |
Collapse
|