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Figueiredo CA, Düsedau HP, Steffen J, Ehrentraut S, Dunay MP, Toth G, Reglödi D, Heimesaat MM, Dunay IR. The neuropeptide PACAP alleviates T. gondii infection-induced neuroinflammation and neuronal impairment. J Neuroinflammation 2022; 19:274. [PMCID: PMC9675261 DOI: 10.1186/s12974-022-02639-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 10/23/2022] [Indexed: 11/21/2022] Open
Abstract
Background Cerebral infection with the protozoan Toxoplasma gondii (T. gondii) is responsible for inflammation of the central nervous system (CNS) contributing to subtle neuronal alterations. Albeit essential for brain parasite control, continuous microglia activation and recruitment of peripheral immune cells entail distinct neuronal impairment upon infection-induced neuroinflammation. PACAP is an endogenous neuropeptide known to inhibit inflammation and promote neuronal survival. Since PACAP is actively transported into the CNS, we aimed to assess the impact of PACAP on the T. gondii-induced neuroinflammation and subsequent effects on neuronal homeostasis. Methods Exogenous PACAP was administered intraperitoneally in the chronic stage of T. gondii infection, and brains were isolated for histopathological analysis and determination of pathogen levels. Immune cells from the brain, blood, and spleen were analyzed by flow cytometry, and the further production of inflammatory mediators was investigated by intracellular protein staining as well as expression levels by RT-qPCR. Neuronal and synaptic alterations were assessed on the transcriptional and protein level, focusing on neurotrophins, neurotrophin-receptors and signature synaptic markers. Results Here, we reveal that PACAP administration reduced the inflammatory foci and the number of apoptotic cells in the brain parenchyma and restrained the activation of microglia and recruitment of monocytes. The neuropeptide reduced the expression of inflammatory mediators such as IFN-γ, IL-6, iNOS, and IL-1β. Moreover, PACAP diminished IFN-γ production by recruited CD4+ T cells in the CNS. Importantly, PACAP promoted neuronal health via increased expression of the neurotrophin BDNF and reduction of p75NTR, a receptor related to neuronal cell death. In addition, PACAP administration was associated with increased expression of transporters involved in glutamatergic and GABAergic signaling that are particularly affected during cerebral toxoplasmosis. Conclusions Together, our findings unravel the beneficial effects of exogenous PACAP treatment upon infection-induced neuroinflammation, highlighting the potential implication of neuropeptides to promote neuronal survival and minimize synaptic prejudice. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02639-z.
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Affiliation(s)
- Caio Andreeta Figueiredo
- grid.5807.a0000 0001 1018 4307Institute of Inflammation and Neurodegeneration, Health Campus Immunology, Infectiology and Inflammation (GC-I3), Otto-Von-Guericke University, Magdeburg, Germany
| | - Henning Peter Düsedau
- grid.5807.a0000 0001 1018 4307Institute of Inflammation and Neurodegeneration, Health Campus Immunology, Infectiology and Inflammation (GC-I3), Otto-Von-Guericke University, Magdeburg, Germany
| | - Johannes Steffen
- grid.5807.a0000 0001 1018 4307Institute of Inflammation and Neurodegeneration, Health Campus Immunology, Infectiology and Inflammation (GC-I3), Otto-Von-Guericke University, Magdeburg, Germany
| | - Stefanie Ehrentraut
- grid.5807.a0000 0001 1018 4307Institute of Inflammation and Neurodegeneration, Health Campus Immunology, Infectiology and Inflammation (GC-I3), Otto-Von-Guericke University, Magdeburg, Germany
| | - Miklos P. Dunay
- grid.483037.b0000 0001 2226 5083Department and Clinic of Surgery and Ophthalmology, University of Veterinary Medicine, Budapest, Hungary
| | - Gabor Toth
- grid.9008.10000 0001 1016 9625Department of Medical Chemistry, University of Szeged, Budapest, Hungary
| | - Dora Reglödi
- grid.9679.10000 0001 0663 9479Department of Anatomy, MTA-PTE PACAP Research Team and Szentagothai Research Center, University of Pecs Medical School, Pecs, Hungary
| | - Markus M. Heimesaat
- grid.6363.00000 0001 2218 4662Institute of Microbiology, Infectious Diseases and Immunology, Charité - University Medicine Berlin, Berlin, Germany
| | - Ildiko Rita Dunay
- grid.5807.a0000 0001 1018 4307Institute of Inflammation and Neurodegeneration, Health Campus Immunology, Infectiology and Inflammation (GC-I3), Otto-Von-Guericke University, Magdeburg, Germany ,grid.418723.b0000 0001 2109 6265Center for Behavioral Brain Sciences – CBBS, Magdeburg, Germany
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VIP modulates human macrophages phenotype via FPRL1 via activation of RhoA-GTPase and PLC pathways. Inflamm Res 2021; 70:309-321. [PMID: 33502586 DOI: 10.1007/s00011-021-01436-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/26/2020] [Accepted: 01/11/2021] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE AND DESIGN This study is aimed at uncovering the signaling pathways activated by vasoactive intestinal peptide in human macrophages MATERIALS: Human peripheral blood mononuclear cell-derived macrophages were used for the in vitro investigation of the VIP-activated signaling pathways. METHODS AND TREATMENT Time-course and dose-response experiments and siRNA were used in human macrophages co-challenged with various concentrations of VIP and different MAPK pharmacologic inhibitors to investigate signaling pathways activated by VIP. Flow analysis was performed to assess the levels of CD11b, CD35 and CD66. Luminescence spectrometry was used to measure the levels of the released hydrogen peroxide and the intracellular calcium levels in the media. RESULTS Macrophages incubated with VIP showed increased phospho-AKT and phospho-ERK1/2 levels in a GTP-RhoA-GTPase-dependent manner. Similarly, VIP increased intracellular release of H2O2 and calcium via PLC and GTP-RhoA-GTPase, in addition to inducing the expression of CD11b, CD35, CD66 and MMP9. Furthermore, VIP activated P38 MAPK through the cAMP/PKA pathway but was independent of both PLC and RhoA signaling. The above-mentioned VIP effects were mediated via activation of the FPRL1 receptor. CONCLUSION VIP/FPRL1/VPAC/GTP-RhoA-GTPase signaling modulated macrophages phenotype through activation of multiple signaling pathways including ERK1/2, AKT, P38, ROS, cAMP and calcium.
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Delgado M. Immunobiology of the Pituitary Adenylate Cyclase-Activating Peptide. CURRENT TOPICS IN NEUROTOXICITY 2016:691-708. [DOI: 10.1007/978-3-319-35135-3_40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Pituitary Adenylate Cyclase-Activating Polypeptide Reverses Ammonium Metavanadate-Induced Airway Hyperresponsiveness in Rats. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015. [PMID: 26199679 PMCID: PMC4496651 DOI: 10.1155/2015/787561] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The rate of atmospheric vanadium is constantly increasing due to fossil fuel combustion. This environmental pollution favours vanadium exposure in particular to its vanadate form, causing occupational bronchial asthma and bronchitis. Based on the well admitted bronchodilator properties of the pituitary adenylate cyclase-activating polypeptide (PACAP), we investigated the ability of this neuropeptide to reverse the vanadate-induced airway hyperresponsiveness in rats. Exposure to ammonium metavanadate aerosols (5 mg/m3/h) for 15 minutes induced 4 hours later an array of pathophysiological events, including increase of bronchial resistance and histological alterations, activation of proinflammatory alveolar macrophages, and increased oxidative stress status. Powerfully, PACAP inhalation (0.1 mM) for 10 minutes alleviated many of these deleterious effects as demonstrated by a decrease of bronchial resistance and histological restoration. PACAP reduced the level of expression of mRNA encoding inflammatory chemokines (MIP-1α, MIP-2, and KC) and cytokines (IL-1α and TNF-α) in alveolar macrophages and improved the antioxidant status. PACAP reverses the vanadate-induced airway hyperresponsiveness not only through its bronchodilator activity but also by counteracting the proinflammatory and prooxidative effects of the metal. Then, the development of stable analogs of PACAP could represent a promising therapeutic alternative for the treatment of inflammatory respiratory disorders.
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Modulatory effects of vasoactive intestinal peptide on intestinal mucosal immunity and microbial community of weaned piglets challenged by an enterotoxigenic Escherichia coli (K88). PLoS One 2014; 9:e104183. [PMID: 25101851 PMCID: PMC4125177 DOI: 10.1371/journal.pone.0104183] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 07/11/2014] [Indexed: 01/08/2023] Open
Abstract
Toll-like receptors (TLRs) recognize microbial pathogens and trigger immune response, but their regulation by neuropeptide-vasoactive intestinal peptide (VIP) in weaned piglets infected by enterotoxigenic Escherichia coli (ETEC) K88 remains unexplored. Therefore, the study was conducted to investigate its role using a model of early weaned piglets infected by ETEC K88. Male Duroc×Landrace×Yorkshire piglets (n = 24) were randomly divided into control, ETEC K88, VIP, and ETEC K88+VIP groups. On the first three days, ETEC K88 and ETEC K88+VIP groups were orally administrated with ETEC K88, other two groups were given sterile medium. Then each piglet from VIP and ETEC K88+VIP group received 10 nmol VIP intraperitoneally (i.p.) once daily, on day four and six. On the seventh day, the piglets were sacrificed. The results indicated that administration of VIP improved the growth performance, reduced diarrhea incidence of ETEC K88 challenged pigs, and mitigated the histopathological changes of intestine. Serum levels of IL-2, IL-6, IL-12p40, IFN-γ and TNF-α in the ETEC K88+ VIP group were significantly reduced compared with those in the ETEC group. VIP significantly increased IL-4, IL-10, TGF-β and S-IgA production compared with the ETEC K88 group. Besides, VIP could inhibit the expression of TLR2, TLR4, MyD88, NF-κB p65 and the phosphorylation of IκB-α, p-ERK, p-JNK, and p-38 induced by ETEC K88. Moreover, VIP could upregulate the expression of occludin in the ileum mucosa compared with the ETEC K88 group. Colon and caecum content bacterial richness and diversity were lower for pigs in the ETEC group than the unchallenged groups. These results demonstrate that VIP is beneficial for the maturation of the intestinal mucosal immune system and elicited local immunomodulatory activities. The TLR2/4-MyD88 mediated NF-κB and MAPK signaling pathway may be critical to the mechanism underlying the modulatory effect of VIP on intestinal mucosal immune function and bacterial community.
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Vacas E, Muñoz-Moreno L, Fernández-Martínez AB, Bajo AM, Sánchez-Chapado M, Prieto JC, Carmena MJ. Signalling pathways involved in antitumoral effects of VIP in human renal cell carcinoma A498 cells: VIP induction of p53 expression. Int J Biochem Cell Biol 2014; 53:295-301. [PMID: 24905957 DOI: 10.1016/j.biocel.2014.05.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 05/21/2014] [Accepted: 05/26/2014] [Indexed: 01/04/2023]
Abstract
Vasoactive intestinal peptide (VIP) decreases cell proliferation through PI3K signalling and prevents tumour progression in clear renal cell carcinoma (RCC). Here we analyzed the signalling pathways that mediate such VIP effects by using human RCC A498 cells. The effects of treatment with 1 μM VIP and/or specific protein kinase inhibitors such as H89, Wortmannin and PD98059 were studied by cell adhesion assay, ELISA of VEGF165 and ROS production assays. Semiquantitative RT-PCR and western blot were performed to study p53 expression. VIP increased cell adhesion and ROS production, and decreased VEGF165 secretion through PI3K signalling. Moreover, VIP increased nuclear expression of tumour suppressor p53. VIP effects could be blocked by cell incubation with a specific p53 inhibitor, cyclin pifithrin-α hydrobromide (CPFT-αH). In conclusion, this study provides a p53-dependent mechanism by which VIP regulates cell proliferation in RCC development. It supports a potential usefulness of VIP in new therapies of RCC.
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Affiliation(s)
- Eva Vacas
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Laura Muñoz-Moreno
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Ana B Fernández-Martínez
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Ana M Bajo
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
| | - Manuel Sánchez-Chapado
- Department of Surgery and Medical and Social Sciences, Unit of Surgery, University of Alcalá, 28871 Alcalá de Henares, Spain; Department of Urology, Príncipe de Asturias Hospital, 28871 Alcalá de Henares, Spain
| | - Juan C Prieto
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain.
| | - María J Carmena
- Department of Systems Biology, Unit of Biochemistry and Molecular Biology, University of Alcalá, 28871 Alcalá de Henares, Spain
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Delgado M, Ganea D. Vasoactive intestinal peptide: a neuropeptide with pleiotropic immune functions. Amino Acids 2011; 45:25-39. [PMID: 22139413 DOI: 10.1007/s00726-011-1184-8] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 11/22/2011] [Indexed: 01/07/2023]
Abstract
Vasoactive intestinal peptide (VIP), a 28-amino acid neuropeptide/neurotransmitter, is widely distributed in both the central and peripheral nervous system. VIP is released by both neurons and immune cells. Various cell types, including immune cells, express VIP receptors. VIP has pleiotropic effects as a neurotransmitter, immune regulator, vasodilator and secretagogue. This review is focused on VIP production and effects on immune cells, VIP receptor signaling as related to immune functions, and the involvement of VIP in inflammatory and autoimmune disorders. The review addresses present clinical use of VIP and future therapeutic directions.
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Affiliation(s)
- Mario Delgado
- Instituto de Parasitologia y Biomedicina, IPBLN-CSIC, Granada, Spain
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8
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Vetrini F, Brunetti-Pierri N, Palmer DJ, Bertin T, Grove NC, Finegold MJ, Ng P. Vasoactive intestinal peptide increases hepatic transduction and reduces innate immune response following administration of helper-dependent Ad. Mol Ther 2010; 18:1339-45. [PMID: 20461064 PMCID: PMC2911263 DOI: 10.1038/mt.2010.84] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 04/14/2010] [Indexed: 01/27/2023] Open
Abstract
Helper-dependent adenoviral vectors (HDAd) are effective tools for liver-directed gene therapy because they can mediate long-term transgene expression in the absence of chronic toxicity. However, high vector doses required for efficient hepatocyte transduction by intravascular delivery result in systemic vector dissemination and dose-dependent activation of the innate immunity. Therefore, strategies to achieve high-efficiency hepatocyte transduction using low vector doses and/or to reduce the acute elevations of proinflammatory cytokines and chemokines may have significant clinical potential. Vasoactive intestinal peptide (VIP) is an endogenous neuropeptide involved in the regulation of hepatic blood flow and plays an important role as modulator of immune functions. Here, we show that VIP pretreatment in mice is able to increase hepatocyte transduction by HDAd, decrease vector uptake by the spleen, reduce elevation of proinflammatory serum cytokines interleukin (IL)-6 and IL-12, and reduce serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) following intravenous HDAd injection. VIP pretreatment also resulted in a reduction in the expression of the chemokines macrophage-inflammatory protein 2 (MIP-2), monocyte chemotactic protein 1 (MCP-1), and regulated on activation normal T-cell expressed and secreted (RANTES) in the livers of mice injected with HDAd. These results suggest that VIP can improve the therapeutic index of HDAd by increasing hepatocyte transduction efficiency while reducing cytokine and chemokine expression following intravascular delivery of HDAd.
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Affiliation(s)
- Francesco Vetrini
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030, USA
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9
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Vaudry D, Falluel-Morel A, Bourgault S, Basille M, Burel D, Wurtz O, Fournier A, Chow BKC, Hashimoto H, Galas L, Vaudry H. Pituitary Adenylate Cyclase-Activating Polypeptide and Its Receptors: 20 Years after the Discovery. Pharmacol Rev 2009; 61:283-357. [DOI: 10.1124/pr.109.001370] [Citation(s) in RCA: 829] [Impact Index Per Article: 55.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Smalley SGR, Barrow PA, Foster N. Immunomodulation of innate immune responses by vasoactive intestinal peptide (VIP): its therapeutic potential in inflammatory disease. Clin Exp Immunol 2009; 157:225-34. [PMID: 19604262 DOI: 10.1111/j.1365-2249.2009.03956.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Since the late 1970s a number of laboratories have studied the role of vasoactive intestinal peptide (VIP) in inflammation and immunity. These studies have highlighted the dramatic effect of VIP on immune cell activation and function, and studies using animal models of disease have indicated that VIP has significant therapeutic and prophylactic potential. This review will focus on the effects of VIP on innate immune cell function and discuss the therapeutic potential for VIP in inflammatory diseases of humans.
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Affiliation(s)
- S G R Smalley
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Leicestershire, UK
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11
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Lee H, Park K, Kim JS, Lee SJ. Vasoactive intestinal peptide inhibits toll-like receptor 3-induced nitric oxide production in Schwann cells and subsequent sensory neuronal cell death in vitro. J Neurosci Res 2009; 87:171-8. [PMID: 18683246 DOI: 10.1002/jnr.21820] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have previously reported that polyinosinic-polycytidylic acids [poly(I:C)], a synthetic toll-like receptor 3 (TLR3) agonist, induce Schwann cell activation, which exerts neurotoxic effects on sensory neurons. In this study, we investigated the effects of vasoactive intestinal peptide (VIP), a neuropeptide implicated in nerve regeneration, on TLR3-induced Schwann cell activation. VIP receptors VPAC1 and VPAC2 were constitutively expressed in rat Schwann cells. VIP pretreatment inhibited TLR3-induced inducible nitric oxide synthase (iNOS) gene expression and NO production in Schwann cells. Studies on the intracellular signal transduction pathways indicate that the VIP effect is mediated by protein kinase A activation. VIP also inhibited the poly(I:C)-induced p38 activation that is responsible for the iNOS gene expression in Schwann cells. Finally, VIP inhibited dorsal rooyt ganglion neuronal cell death caused by NO produced in activated Schwann cells. Taken together, our data suggest that VIP exerts a neuroprotective effect by inhibiting neurotoxic Schwann cell activation.
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Affiliation(s)
- Hyunkyoung Lee
- Program in Molecular and Cellular Neuroscience, DRI, and Department of Oral Physiology, School of Dentistry, Seoul National University, Seoul, Korea
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Abstract
Pharmaceutical companies are facing an increasing interest in new target identification and validation. In particular, extensive efforts are being made in the field of protein kinase inhibitors research and development, and the past ten years of effort in this field have altered our perception of the potential of kinases as drug targets. Therefore, in the drug discovery process, the selection of relevant, susceptible protein kinase targets combined with searches for leads and candidates have become a crucial approach. The success of recent launches of protein kinase inhibitors (Gleevec, Imatinib, Sutent, Iressa, Nexavar, Sprycel) gave another push to this field. Numerous other kinase inhibitors are currently undergoing clinical trials or clinical development. Some questions are nevertheless unanswered, mostly related to the great number of known kinases in the human genome, to their similarity with each other, to the existence of functionally redundant kinases for specific pathways, and also because the connection between particular pathways and diseases is not always clear. The review is leading the reader through a panoramic view of protein kinase inhibition with a major focus on MAPK, successful examples and clinical candidates.
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Affiliation(s)
- Simona Margutti
- Institute of Pharmacy, Department of Pharmaceutical and Medicinal Chemistry; Eberhard Karls University of Tuebingen, Auf der Morgenstelle 8, 72076 Tuebingen, Germany
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Suppression of T-lymphocyte activation and chemotaxis by the adenylate cyclase toxin of Bordetella pertussis. Infect Immun 2008; 76:2822-32. [PMID: 18426886 DOI: 10.1128/iai.00200-08] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The adenylate cyclase toxin (CyaA) released by Bordetella pertussis is an essential virulence factor for colonization of the host. This toxin inhibits migration and activation of phagocytes, thereby preventing bacterial killing. In addition, CyaA interferes with the initiation of adaptive immunity by misdirecting dendritic cell differentiation to a suppressive rather than stimulatory phenotype. Here we show that CyaA directly affects adaptive responses by catalyzing cyclic AMP (cAMP) production in peripheral blood lymphocytes. Treatment with CyaA resulted in profound impairment of T-lymphocyte activation and chemotaxis. These effects resulted from inhibition of T-cell antigen receptor and chemokine receptor signaling via a cAMP/protein kinase A (PKA)-dependent pathway. A comparison of the activities of CyaA on T-cell and macrophage activation and migration revealed that the biological effects of the toxin were paralleled by inhibition of the activation of mitogen-activated protein (MAP) kinases, highlighting the conclusion that the ubiquitous and evolutionarily conserved MAP kinase modules are common targets of the PKA-mediated immunosuppressant activities of CyaA and underlining the potential of cAMP-elevating toxins as a means of evasion of immunity by bacterial pathogens.
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POZO DAVID, GONZALEZ-REY ELENA, CHORNY ALEJO, ANDERSON PER, VARELA NIEVES, DELGADO MARIO. Tuning immune tolerance with vasoactive intestinal peptide: a new therapeutic approach for immune disorders. Peptides 2007; 28:1833-46. [PMID: 17521775 PMCID: PMC2071927 DOI: 10.1016/j.peptides.2007.04.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 03/25/2007] [Accepted: 04/10/2007] [Indexed: 01/09/2023]
Abstract
The induction of immune tolerance is essential for the maintenance of immune homeostasis and to limit the occurrence of exacerbated inflammatory and autoimmune conditions. Multiple mechanisms act together to ensure self-tolerance, including central clonal deletion, cytokine deviation and induction of regulatory T cells. Identifying the factors that regulate these processes is crucial for the development of new therapies of autoimmune diseases and transplantation. The vasoactive intestinal peptide (VIP) is a well-characterized endogenous anti-inflammatory neuropeptide with therapeutic potential for a variety of immune disorders. Here, we examine the latest research findings, which indicate that VIP participates in maintaining immune tolerance in two distinct ways: by regulating the balance between pro-inflammatory and anti-inflammatory factors, and by inducing the emergence of regulatory T cells with suppressive activity against autoreactive T-cell effectors.
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Affiliation(s)
- DAVID POZO
- Departamento de Bioquimica Medica y Biologia Molecular, Universidad de Sevilla, Sevilla 41009, Spain
| | - ELENA GONZALEZ-REY
- Departamento de Bioquimica Medica y Biologia Molecular, Universidad de Sevilla, Sevilla 41009, Spain
| | - ALEJO CHORNY
- Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas, Granada 18100, Spain
| | - PER ANDERSON
- Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas, Granada 18100, Spain
| | - NIEVES VARELA
- Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas, Granada 18100, Spain
| | - MARIO DELGADO
- Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas, Granada 18100, Spain
- *Corresponding Author: Mario Delgado, Instituto de Parasitologia y Biomedicina, CSIC, Avd. Conocimiento, PT Ciencias de la Salud, Granada 18100, Spain. Phone: 34-958-181665. Fax: 34-958-181632.
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Varela N, Chorny A, Gonzalez-Rey E, Delgado M. Tuning inflammation with anti-inflammatory neuropeptides. Expert Opin Biol Ther 2007; 7:461-78. [PMID: 17373898 DOI: 10.1517/14712598.7.4.461] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The immune system is confronted with the daunting task of defending the organism against invading pathogens while at the same time remaining self-tolerant to the body's own constituents and preserving its integrity. The loss of immune tolerance stemming from an unbalance in pro-inflammatory factors versus anti-inflammatory cytokines, or of autoreactive/inflammatory T helper 1 cells versus regulatory/suppressive T cells, results in the breakdown of immune homeostasis and the subsidiary appearance of exacerbated inflammatory and autoimmune diseases. Some neuropeptides have been shown to have anti-inflammatory properties and to participate in maintaining immune tolerance. Here the authors examine the most recent developments in this field and highlight the effectiveness of using neuropeptides in treating several inflammatory and autoimmune disorders.
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Affiliation(s)
- Nieves Varela
- Instituto de Parasitologia y Biomedicina, Consejo Superior de Investigaciones Cientificas (CSIC), Avd. Conocimiento, PT Ciencias de la Salud, Granada 18100, Spain.
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Abstract
Infectious microbes face an unwelcoming environment in their mammalian hosts, which have evolved elaborate multicelluar systems for recognition and elimination of invading pathogens. A common strategy used by pathogenic bacteria to establish infection is to secrete protein factors that block intracellular signalling pathways essential for host defence. Some of these proteins also act as toxins, directly causing pathology associated with disease. Bacillus anthracis, the bacterium that causes anthrax, secretes two plasmid-encoded enzymes, LF (lethal factor) and EF (oedema factor), that are delivered into host cells by a third bacterial protein, PA (protective antigen). The two toxins act on a variety of cell types, disabling the immune system and inevitably killing the host. LF is an extraordinarily selective metalloproteinase that site-specifically cleaves MKKs (mitogen-activated protein kinase kinases). Cleavage of MKKs by LF prevents them from activating their downstream MAPK (mitogen-activated protein kinase) substrates by disrupting a critical docking interaction. Blockade of MAPK signalling functionally impairs cells of both the innate and adaptive immune systems and induces cell death in macrophages. EF is an adenylate cyclase that is activated by calmodulin through a non-canonical mechanism. EF causes sustained and potent activation of host cAMP-dependent signalling pathways, which disables phagocytes. Here I review recent progress in elucidating the mechanisms by which LF and EF influence host signalling and thereby contribute to disease.
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Affiliation(s)
- Benjamin E Turk
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
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Chorny A, Gonzalez-Rey E, Varela N, Robledo G, Delgado M. Signaling mechanisms of vasoactive intestinal peptide in inflammatory conditions. ACTA ACUST UNITED AC 2006; 137:67-74. [PMID: 16949684 DOI: 10.1016/j.regpep.2006.04.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 04/25/2006] [Accepted: 04/28/2006] [Indexed: 11/20/2022]
Abstract
The vasoactive intestinal peptide (VIP) is a neuropeptide belonging to the secretin/glucagon family of peptides, which exerts a wide spectrum of immunological functions controlling the homeostasis of immune system through different receptors expressed in various immunocompetent cells. In the last decade, VIP has emerged as a potent anti-inflammatory factor, which exerts its function by regulating the production of both anti- and pro-inflammatory mediators. In this sense, VIP has been proposed as a promising candidate, alternative to other existing treatments, for treating acute and chronic inflammatory and autoimmune diseases, such as septic shock, rheumatoid arthritis, multiple sclerosis and Crohn's disease. The present work reviews the involvement of the specific receptors and or different transduction pathways and transcription factors in the anti-inflammatory action of VIP, and their implication on its therapeutic effect on inflammatory/autoimmune disorders.
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Affiliation(s)
- Alejo Chorny
- Instituto de Parasitologia y Biomedicina, CSIC, Avd. Conocimiento, PT Ciencias de la Salud, Granada 18100, Spain
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Juarranz Y, Abad C, Martinez C, Arranz A, Gutierrez-Cañas I, Rosignoli F, Gomariz RP, Leceta J. Protective effect of vasoactive intestinal peptide on bone destruction in the collagen-induced arthritis model of rheumatoid arthritis. Arthritis Res Ther 2005; 7:R1034-45. [PMID: 16207319 PMCID: PMC1257432 DOI: 10.1186/ar1779] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 05/17/2005] [Accepted: 06/02/2005] [Indexed: 12/04/2022] Open
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology, characterized by the presence of inflammatory synovitis accompanied by destruction of joint cartilage and bone. Treatment with vasoactive intestinal peptide (VIP) prevents experimental arthritis in animal models by downregulation of both autoimmune and inflammatory components of the disease. The aim of this study was to characterize the protective effect of VIP on bone erosion in collagen-induced arthritis (CIA) in mice. We have studied the expression of different mediators implicated in bone homeostasis, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), receptor activator of nuclear factor-κB (RANK), receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), IL-1, IL-4, IL-6, IL-10, IL-11 and IL-17. Circulating cytokine levels were assessed by ELISA and the local expression of mediators were determined by RT-PCR in mRNA extracts from joints. VIP treatment resulted in decreased levels of circulating IL-6, IL-1β and TNFα, and increased levels of IL-4 and IL-10. CIA-mice treated with VIP presented a decrease in mRNA expression of IL-17, IL-11 in the joints. The ratio of RANKL to OPG decreased drastically in the joint after VIP treatment, which correlated with an increase in levels of circulating OPG in CIA mice treated with VIP. In addition, VIP treatment decreased the expression of mRNA for RANK, iNOS and COX-2. To investigate the molecular mechanisms involved, we tested the activity of NFκB and AP-1, two transcriptional factors closely related to joint erosion, by EMSA in synovial cells from CIA mice. VIP treatment in vivo was able to affect the transcriptional activity of both factors. Our data indicate that VIP is a viable candidate for the development of treatments for RA.
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MESH Headings
- Animals
- Arthritis, Experimental/drug therapy
- Arthritis, Experimental/genetics
- Arthritis, Experimental/metabolism
- Bone and Bones/drug effects
- Bone and Bones/metabolism
- Cyclooxygenase 2/metabolism
- Cytokines/biosynthesis
- Cytokines/blood
- Cytokines/genetics
- Disease Models, Animal
- Drug Evaluation
- Gene Expression Profiling
- Glycoproteins/blood
- I-kappa B Proteins/blood
- Inflammation Mediators/blood
- JNK Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Male
- Mice
- Mice, Inbred DBA
- NF-KappaB Inhibitor alpha
- NF-kappa B/antagonists & inhibitors
- Nitric Oxide Synthase Type II/metabolism
- Osteoclasts/drug effects
- Osteoclasts/metabolism
- Osteolysis/etiology
- Osteolysis/metabolism
- Osteolysis/prevention & control
- Osteoprotegerin
- Protein Transport/drug effects
- Proto-Oncogene Proteins c-jun/blood
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Receptors, Cytoplasmic and Nuclear/blood
- Receptors, Tumor Necrosis Factor/blood
- Transcription Factor AP-1/metabolism
- Transcription, Genetic/drug effects
- Vasoactive Intestinal Peptide/pharmacology
- Vasoactive Intestinal Peptide/therapeutic use
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Affiliation(s)
- Yasmina Juarranz
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
| | - Catalina Abad
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
| | - Carmen Martinez
- Departamento Biología Celular, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain
| | - Alicia Arranz
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
| | - Irene Gutierrez-Cañas
- Servicio de Reumatología y Unidad de Investigación, Hospital 12 de Octubre, Madrid, Spain
| | - Florencia Rosignoli
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
| | - Rosa P Gomariz
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
| | - Javier Leceta
- Departamento Biología Celular, Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
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19
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Hsiao CJJ, Stapleton SR. Characterization of Cd-induced molecular events prior to cellular damage in primary rat hepatocytes in culture: activation of the stress activated signal protein JNK and transcription factor AP-1. J Biochem Mol Toxicol 2005; 18:133-42. [PMID: 15252869 DOI: 10.1002/jbt.20018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The effect of Cadmium (Cd) on the expression of c-Jun N-terminal kinase (JNK), c-jun, and activator protein-1 (AP-1) has been investigated. We previously reported that Cd causes cell damage as indicated by increases in the cytotoxic parameters, lactate dehydrogenase and lipid peroxidation, and this damage was mediated by decreases in cellular concentration of glutathione. In the present study, we investigate the molecular events involved prior to the Cd-induced cellular toxicity and damage in primary rat hepatocytes. We propose that Cd, through the generation of reactive oxygen species (ROS) and prior to significant cellular damage, activates the stress activated signal protein JNK, regulates c-jun expression, and promotes the binding of a redox sensitive transcription factor AP-1. We show JNK activity and c-jun mRNA level significantly increased at 1 h and AP-1 DNA binding activity significantly enhanced at 3 h in the presence of 4 microM cadmium chloride. Blocking the Cd induction of JNK activity, c-jun mRNA level, and AP-1 binding activity using the antioxidants N-acetyl cysteine (10 mM) or carnosol (0.5 microg/mL) suggests a role for ROS. Blocking JNK activity and c-jun mRNA by SP600125 (20 microM), a JNK inhibitor, supports the role of JNK in transmission of signals induced by Cd.
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Affiliation(s)
- Chin-ju J Hsiao
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
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20
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Hur KC. Protein Kinase a functions as a negative regulator of c‐jun n‐terminal kinase but not of p38 mitogen‐activated protein Kinase in PC12 cells. ACTA ACUST UNITED AC 2005. [DOI: 10.1080/17386357.2005.9647268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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21
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Nonaka N, Shioda S, Banks WA. Effect of lipopolysaccharide on the transport of pituitary adenylate cyclase activating polypeptide across the blood–brain barrier. Exp Neurol 2005; 191:137-44. [PMID: 15589520 DOI: 10.1016/j.expneurol.2004.09.013] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Revised: 09/13/2004] [Accepted: 09/27/2004] [Indexed: 11/16/2022]
Abstract
Pituitary adenylate cyclase activating polypeptide (PACAP) has neuroprotective effects against ischemia, even when given by intravenous (iv) administration 24 h after stroke. Transport of PACAP across the blood-brain barrier (BBB) by peptide transport system (PTS)-6 underlies its effectiveness after iv administration. However, PACAP transport is modified after central nervous system (CNS) injury, raising the question of whether cytokines or BBB disruption affects PTS-6 activity. Lipopolysaccharide (LPS) is derived from bacterial cell walls and affects the passage of other proteins across the BBB through its release of cytokines and disruption of the BBB. Here, we examined by several methods the transport of radioactively labeled PACAP (I-PACAP) across the BBB after intraperitoneal (ip) injection of LPS. After three doses of LPS, studies at a single time point found a differential effect of LPS on the brain/serum ratio for I-PACAP and radioactively labeled albumin (I-Albumin). Whereas LPS increased the ratio for I-Albumin, demonstrating BBB disruption, it decreased the ratio for I-PACAP. Multiple-time regression analysis, capillary depletion, and brain perfusion showed that this decrease was fully explained by a decrease in the initial, reversible binding of I-PACAP to brain endothelium, while the rate of transport of PACAP into the brain was not altered. These methods also showed that the LPS-treated mice were volume contracted. This volume contraction concentrated the amount of I-PACAP in the blood and so increased the amount of I-PACAP presented to the BBB. Lack of change in transport rate combined with volume contraction resulted in a net increase of about 30% of the iv dose of I-PACAP entering the brain. LPS did not alter the efflux of I-PACAP from the CNS. In conclusion, PTS-6 remains active and should be able to deliver therapeutic amounts of PACAP to the CNS in brain injuries involving cytokine release and BBB disruption.
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Affiliation(s)
- Naoko Nonaka
- Department of Oral Anatomy, Showa University School of Dentistry, Tokyo, Japan.
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22
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Delgado M, Pozo D, Ganea D. The significance of vasoactive intestinal peptide in immunomodulation. Pharmacol Rev 2004; 56:249-90. [PMID: 15169929 DOI: 10.1124/pr.56.2.7] [Citation(s) in RCA: 295] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
First identified by Said and Mutt some 30 years ago, the vasoactive intestinal peptide (VIP) was originally isolated as a vasodilator peptide. Subsequently, its biochemistry was elucidated, and within the 1st decade, their signature features as a neuropeptide became consolidated. It did not take long for these insights to permeate the field of immunology, out of which surprising new attributes for VIP were found in the last years. VIP is rapidly transforming into something more than a mere hormone. In evolving scientifically from a hormone to a novel agent for modifying immune function and possibly a cytokine-like molecule, VIP research has engaged many physiologists, molecular biologists, biochemists, endocrinologists, and pharmacologists and it is a paradigm to explore mutual interactions between neural and neuroendocrine links in health and disease. The aim of this review is firstly to update our knowledge of the cellular and molecular events relevant to VIP function on the immune system and secondly to gather together recent data that support its role as a type 2 cytokine. Recognition of the central functions VIP plays in cellular processes is focusing our attention on this "very important peptide" as exciting new candidates for therapeutic intervention and drug development.
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Affiliation(s)
- Mario Delgado
- Instituto de Parasitologia y Biomedicina "Lopez Neyra," Calle Ventanilla 11, Granada 18001, Spain.
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23
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Delgado M, Abad C, Martinez C, Juarranz MG, Leceta J, Ganea D, Gomariz RP. PACAP in immunity and inflammation. Ann N Y Acad Sci 2003; 992:141-57. [PMID: 12794054 DOI: 10.1111/j.1749-6632.2003.tb03145.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide belonging to the VIP/secretin/glucagon family of peptides, produced by the lymphoid cells, which exerts a wide spectrum of immunological functions controlling the homeostasis of immune system through different receptors expressed in various immunocompetent cells. In the last decade, PACAP has been clearly identified as a potent anti-inflammatory factor that exerts its function by regulating the production of both anti- and proinflammatory mediators. In this sense, PACAP prevents death by septic shock, an acute inflammatory disease with a high mortality. In addition, PACAP regulates the expression of costimulatory molecules, inasmuch as this related to the modulation in the shift from Th1 towards Th2 differentiation. We recently reported that PACAP prevents the deleterious effects of arthritis by downregulating both inflammatory and autoimmune components of the disease. Therefore, PACAP and analogs have been proposed as very promising candidates, alternative to other existing treatments, for treating acute and chronic inflammatory and autoimmune diseases, such as septic shock, arthritis, multiple sclerosis, Crohn's disease, or autoimmune diabetes.
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Affiliation(s)
- Mario Delgado
- Department of Cell Biology, School of Biology, Complutense University, Madrid 28040, Spain.
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24
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Ganea D, Delgado M. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) as modulators of both innate and adaptive immunity. CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 2002; 13:229-37. [PMID: 12090463 DOI: 10.1177/154411130201300303] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The structurally related neuropeptides VIP and PACAP are released within the lymphoid organs following antigenic stimulation, and modulate the function of inflammatory cells through specific receptors. In activated macrophages, VIP and PACAP inhibit the production of pro-inflammatory agents (cytokines, chemokines, and nitric oxide), and stimulate the production of the anti-inflammatory cytokine IL-10. These events are mediated through the VIP/PACAP effects on de novo expression or nuclear translocation of several transcription factors, i.e., NFkappaB, CREB, c-Jun, JunB, and IRF-1. The in vivo administration of VIP/PACAP results in a similar pattern of cytokine and chemokine modulation, which presumably mediates the protective effect of VIP/PACAP in septic shock. In addition, VIP/PACAP reduce the expression of the co-stimulatory molecules B7.1/B7.2, and the subsequent stimulatory activity of macrophages for T-helper cells. In T-cells expressing specific VIP/PACAP receptors, VIP and PACAP inhibit the expression of FasL through effects on NFkappaB, NFAT, and Egr2/3. The reduction of FasL expression has several biological consequences: inhibition of antigen-induced cell death in CD4 T-cells, inhibition of the FasL-mediated cytotoxicity of CD8 and CD4 effectors against direct and bystander targets, and promotion of long-term memory Th2 cells, through a positive effect on the survival of Th2, but not Th1, effectors. The various biological effects of VIP and PACAP are discussed within the range of a general anti-inflammatory model.
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Affiliation(s)
- Doina Ganea
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA.
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25
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Lonergan PE, Martin DSD, Horrobin DF, Lynch MA. Neuroprotective effect of eicosapentaenoic acid in hippocampus of rats exposed to gamma-irradiation. J Biol Chem 2002; 277:20804-11. [PMID: 11912218 DOI: 10.1074/jbc.m202387200] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Exposure to irradiation leads to detrimental changes in several cell types. In this study we assessed the changes induced in hippocampus by exposure of rats to whole body irradiation; the findings reveal that irradiation leads to apoptotic cell death in hippocampus, and as a consequence, long term potentiation in perforant path-granule cell synapses is markedly impaired. The evidence is consistent with the view that irradiation induced an increase in reactive oxygen species and that this leads to stimulation of the stress-activated protein kinase, JNK, and activation of the transcription factor, c-Jun. Consequent upon activation of JNK, a cascade of cell signaling events was stimulated that ultimately resulted in apoptosis, as suggested by parallel increases in cytochrome c translocation, caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and terminal dUTP nick-end labeling staining. Treatment of rats with eicosapentaenoic acid inhibited the irradiation-induced increase in reactive oxygen species production and the subsequent cellular signaling events, suggesting that oxidative stress triggered apoptotic cell death in the hippocampus of rats exposed to irradiation. Significantly, when the compromise in cell viability induced by irradiation was prevented by eicosapentaenoic acid, long term potentiation was sustained in a manner similar to that in the sham-treated control group.
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Affiliation(s)
- Peter E Lonergan
- Trinity College Institute of Neuroscience, Department of Physiology, Trinity College, Dublin 2, Ireland
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26
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Lynch AM, Lynch MA. The age-related increase in IL-1 type I receptor in rat hippocampus is coupled with an increase in caspase-3 activation. Eur J Neurosci 2002; 15:1779-88. [PMID: 12081657 DOI: 10.1046/j.1460-9568.2002.02012.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Evidence from several studies indicates that expression of interleukin-1beta (IL-1beta) and IL-1 type I receptor is particularly high in hippocampus, and it has recently been shown that the concentration of IL-1beta is increased in the hippocampus of the aged rat. Here we report that this increase is coupled with an increase in expression of IL-1 type I receptor and increased activity of IL-1 receptor-associated kinase. The evidence presented indicates that the age-related increase in activity of the mitogen-activated protein kinases, Jun N-terminal kinase (JNK) and p38, was accompanied by enhanced caspase-3 activity. Analysis of colocalization of activated caspase-3 with activated p38 (p-p38) suggested that p-p38 was necessary for activation of caspase-3; while in vitro analysis indicated that the IL-1beta-induced increase in caspase-3 activity was abrogated by the p38 inhibitor, SB203580. The IL-1beta-induced increase in caspase-3 activity in vitro was also abrogated by vasoactive intestinal peptide, which is a JNK inhibitor; however, colocalization of activated JNK (p-JNK) and activated caspase-3 did not clearly identify JNK as an upstream activator of caspase-3. We propose that these changes are indicative of cell death in aged hippocampus and suggest that they contribute to the age-related decrease in long-term potentiation in perforant path granule cell synapses.
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Affiliation(s)
- Aileen M Lynch
- Trinity College Institute of Neuroscience, Department of Physiology, Trinity College, Dublin 2, Ireland.
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27
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Delgado M. Vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide inhibit the MEKK1/MEK4/JNK signaling pathway in endotoxin-activated microglia. Biochem Biophys Res Commun 2002; 293:771-6. [PMID: 12054537 DOI: 10.1016/s0006-291x(02)00283-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The vasoactive intestinal peptide (VIP) and the pituitary adenylate cyclase-activating polypeptide (PACAP), two immunomodulatory neuropeptides, act as anti-inflammatory factors for activated microglia, by inhibiting the production of proinflammatory factors. In the present study the effects of VIP/PACAP on the MEKK1/MEK4/JNK transduction pathway and on the subsequent changes in Jun family members, a transduction pathway clearly involved in the activation of microglia cells were examined. VIP/PACAP inhibit MEKK1 activity and the subsequent phosphorylations of MEK4, JNK, and c-Jun, which result in a decrease in the AP-1 binding and a marked change in the composition of AP-1 complexes from c-Jun/c-Fos to JunB/c-Fos. Furthermore, VIP stimulates JunB production in LPS-stimulated microglia. Both inhibition of the MEKK1/MEK4/JNK pathway, leading to a reduction in phosphorylated c-Jun, and the stimulation of JunB are mediated through the specific VPAC1 receptor and cAMP/PKA pathway. The VIP/PACAP interference with the stress-induced SAPK/JNK pathway in activated microglia may represent a significant element in the regulation of inflammatory response in the CNS by endogenous neuropeptides.
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Affiliation(s)
- Mario Delgado
- Departamento Biologia Celular, Facultad de Biologia, Universidad Complutense, Madrid 28040, Spain.
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28
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Kelly A, Lynch A, Vereker E, Nolan Y, Queenan P, Whittaker E, O'Neill LA, Lynch MA. The anti-inflammatory cytokine, interleukin (IL)-10, blocks the inhibitory effect of IL-1 beta on long term potentiation. A role for JNK. J Biol Chem 2001; 276:45564-72. [PMID: 11581275 DOI: 10.1074/jbc.m108757200] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Several effects of the proinflammatory cytokine, interleukin-1 beta (IL-1 beta), have been described in the central nervous system, and one area of the brain where marked changes have been reported is the hippocampus. Among these changes are an IL-1 beta-induced inhibition of long term potentiation (LTP) in perforant path-granule cell synapses and an attenuation of glutamate release in synaptosomes prepared from the hippocampus. Evidence suggests that, at least in circulating cells, the anti-inflammatory cytokine, IL-10, antagonizes certain effects of IL-1. We investigated the effect of IL-10 on IL-1 beta-induced inhibition of LTP and glutamate release. The evidence presented indicates that IL-1 beta stimulates the stress-activated protein kinase, c-Jun-activated protein kinase (JNK), and IL-1 receptor-associated kinase, which may explain its inhibitory effect on release and LTP, and that IL-10 reversed the IL-1 beta-induced stimulation of JNK activity and inhibition of release and LTP. We observed that IL-10 abrogated the stimulatory effect of IL-1 beta on superoxide dismutase activity and reactive oxygen species production, whereas the H(2)O(2)-induced inhibition of LTP was also blocked by IL-10. We present evidence that suggests that the action of IL-10 may be mediated by its ability to induce shedding of the IL-1 type I receptor.
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Affiliation(s)
- A Kelly
- Trinity College Institute of Neuroscience, Department of Physiology and Department of Biochemistry, Trinity College, Dublin 2, Ireland
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29
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Vereker E, O'Donnell E, Lynch A, Kelly A, Nolan Y, Lynch MA. Evidence that interleukin-1beta and reactive oxygen species production play a pivotal role in stress-induced impairment of LTP in the rat dentate gyrus. Eur J Neurosci 2001; 14:1809-19. [PMID: 11860476 DOI: 10.1046/j.0953-816x.2001.01809.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Long-term potentiation (LTP) in both area CA1 and the dentate gyrus is attenuated by stress and the evidence is consistent with the view that this is a consequence of increased activation of glucocorticoid receptors, in the hippocampus, following the stress-induced increase in circulating corticosterone. It has been shown that expression of the pro-inflammatory cytokine, interleukin-1beta (IL-1beta), is increased in hippocampus in response to stress; this finding together with the observation that IL-1beta exerts an inhibitory effect on LTP, suggests that IL-1beta may play a key role in mediating this inhibitory effect of stress on LTP. In this study, we explore this possibility and report that stress is also associated with increased reactive oxygen species production. The evidence presented supports the view that this is secondary to the stress-induced increase in IL-1beta concentration, as IL-1beta increased activity of superoxide dismutase and increased reactive oxygen species accumulation in hippocampus in vitro. We report that the inhibitory effect of stress on LTP is mimicked by H2O2, which increases reactive oxygen species accumulation, and by IL-1beta, the effect of which is overcome by the antioxidant, phenylarsine oxide. The hypothesis that the stress-induced increase in reactive oxygen species production may underlie the suppression of LTP is further supported by the finding that the effect of stress is abrogated by dietary manipulation with antioxidant vitamins E and C.
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Affiliation(s)
- E Vereker
- Trinity College Institute of Neuroscience, Department of Physiology, Trinity College, Dublin 2, Ireland
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30
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Leceta J, Gomariz RP, Martinez C, Abad C, Ganea D, Delgado M. Receptors and transcriptional factors involved in the anti-inflammatory activity of VIP and PACAP. Ann N Y Acad Sci 2001; 921:92-102. [PMID: 11193883 DOI: 10.1111/j.1749-6632.2000.tb06954.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
VIP and PACAP modulate the function of inflammatory cells through specific receptors. VIP/PACAP inhibit the production of TNF alpha, IL-6, IL-12, and nitric oxide (NO), and stimulate IL-10 in peritoneal macrophages and Raw 264.7 cells. Here we report on the specific VIP/PACAP receptors, transduction pathways, and transcriptional factors involved in the regulation of these macrophage factors by VIP and PACAP. Both neuropeptides inhibit IL-6 production mainly through PAC1 binding, PKC activation, and the subsequent shedding of the LPS receptor CD14 in macrophages. However, the effects on TNF alpha, IL-10, IL-12, and NO are mostly mediated through the constitutively expressed VPAC1 receptor, although the inducible expressed VPAC2 may also participate. VIP/PACAP binding to VPAC1 induces both a cAMP-dependent and a cAMP-independent pathways that regulate cytokine and NO production at the transcriptional level. VIP/PACAP inhibit TNF alpha through reduction in NFkB binding and changes in the composition of CRE-binding complexes; they inhibit IL-12 through reduction in NFkB binding and changes in the composition of the ets-2 complexes. VIP/PACAP inhibit iNOS expression through reduction in NFkB and IRF-1 binding, and augment IL-10 by increasing CREB-binding. Whereas the inhibition of IRF-1 and CRE-binding complexes seems to be mediated through the cAMP-dependent pathway, VIP/PACAP inhibition of NFkB nuclear translocation is mediated through a reduction in IkB alpha degradation mediated by the cAMP-independent pathway. This study provides new evidence for the understanding of the molecular mechanism by means of which VIP and PACAP attenuate the inflammatory response.
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MESH Headings
- Animals
- Cytokines/biosynthesis
- Gene Expression
- Inflammation/immunology
- Inflammation/metabolism
- Inflammation/prevention & control
- Interleukin-10/genetics
- Interleukin-12/genetics
- Lipopolysaccharide Receptors/genetics
- Macrophages/drug effects
- Macrophages/immunology
- Macrophages/metabolism
- Mice
- Models, Biological
- Neuropeptides/pharmacology
- Nitric Oxide/biosynthesis
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type II
- Pituitary Adenylate Cyclase-Activating Polypeptide
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
- Receptors, Pituitary Hormone/drug effects
- Receptors, Pituitary Hormone/genetics
- Receptors, Pituitary Hormone/metabolism
- Receptors, Vasoactive Intestinal Peptide/drug effects
- Receptors, Vasoactive Intestinal Peptide/genetics
- Receptors, Vasoactive Intestinal Peptide/metabolism
- Receptors, Vasoactive Intestinal Peptide, Type II
- Receptors, Vasoactive Intestinal Polypeptide, Type I
- Signal Transduction
- Transcription Factors/metabolism
- Tumor Necrosis Factor-alpha/genetics
- Vasoactive Intestinal Peptide/pharmacology
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Affiliation(s)
- J Leceta
- Departamento Biologia Celular, Universidad Complutense, Madrid 28040, Spain
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31
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Abstract
The immune response, both in innate and adaptive immunity, is controlled at several levels, including signaling from the central nervous system. Neuropeptides released within the lymphoid organs modulate the immune response, either as stimulators or inhibitors. The subject of this review is the description of macrophage-expressed receptors of inhibitory neuropeptides. We describe the inhibitory effects on macrophage function for several neuropeptides, the receptors that mediate those activities, and the molecular mechanisms initiated by some of these receptors in terms of transduction pathways and transcriptional factors.
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Affiliation(s)
- D Ganea
- Department of Biological Sciences, Rutgers University, 101 Warren Street, Newark, NJ 07102, USA.
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32
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Delgado M, Ganea D. Vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide inhibit expression of Fas ligand in activated T lymphocytes by regulating c-Myc, NF-kappa B, NF-AT, and early growth factors 2/3. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:1028-40. [PMID: 11145682 DOI: 10.4049/jimmunol.166.2.1028] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Activation-induced cell death in T cells, a major mechanism for limiting an ongoing immune response, is initiated by Ag reengagement and mediated through Fas/Fas ligand interactions. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP), two multifunctional neuropeptides, modulate innate and adaptive immunity. We reported previously that VIP/PACAP protect T cells from activation-induced cell death through down-regulation of Fas ligand (FasL). In this study, we investigate the molecular mechanisms involved in the protective effect of VIP and PACAP. VIP/PACAP reduce in a dose-dependent manner anti-CD3-induced apoptosis in 2B4.11 T cell hybridomas. The protective effect is mediated through the specific type 2 VIP receptor, and the cAMP/protein kinase A pathway. A functional study demonstrates that VIP/PACAP inhibit activation-induced FasL expression. VIP/PACAP inhibit the expression and/or DNA-binding activity of several transcriptional factors involved in FasL expression, i.e., c-myc, NF-kappaB, NF-ATp, and early growth factors (Egr) 2/3. The inhibition of NF-kappaB binding is due to the stabilization of I-kappaB (inhibitory protein that dissociates from NF-kappaB), through the inhibition of I-kappaB kinase alpha activity. Subsequently, p65 nuclear translocation is significantly reduced. The inhibition in NF-ATp binding results from a calcineurin-independent reduction in NF-ATp nuclear translocation. VIP/PACAP inhibit the expression of Egr2 and 3, but not of Egr1. The effects on the transcriptional factors are mediated through type 2 VIP receptor with cAMP as secondary messenger.
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Affiliation(s)
- M Delgado
- Department of Biological Sciences, Rutgers University, Newark, NJ 07102, USA
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