802 research outputs found
Identification and structure elucidation of the pro-resolving mediators provides novel leads for resolution pharmacology
"This is the pre-peer reviewed version of the following article: Jesmond, D. and S. C. N "Identification and structure elucidation of the proresolving mediators provides novel leads for resolution pharmacology." British Journal of Pharmacology 0(ja)., which has been published in final form at https://doi.org/10.1111/bph.14336. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."Studies reviewed here from the authorsβ laboratories were supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (Grant number: 107613/Z/15/Z) and the European Research Council (ERC) under the European Unionβs Horizon 2020 research and innovation programme (Grant number: 677542) to JD. Studies reviewed from the CN Serhan laboratories were supported by National Institutes of Health (grant numbers R01GM38765 and P01GM095467)
Pro-Resolving Mediators in Regulating and Conferring Macrophage Function.
Macrophages are central in coordinating the host response to both sterile and infective insults. Clearance of apoptotic cells and cellular debris is a key biological action preformed by macrophages that paves the way to the resolution of local inflammation, repair and regeneration of damaged tissues, and re-establishment of function. The essential fatty acid-derived autacoids termed specialized pro-resolving mediators (SPM) play central roles in promoting these processes. In the present article, we will review the role of microvesicles in controlling macrophage efferocytosis and SPM production. We will also discuss the role of both apoptotic cells and microvesicles in providing substrate for transcellular biosynthesis of several SPM families during efferocyotsis. In addition, this article will discuss the biological actions of the recently uncovered macrophage-derived SPM termed maresins. These mediators are produced via 14-lipoxygenation of docosahexaenoic acid that is either enzymatically converted to mediators carrying two hydroxyl groups or to autacoids that are peptide-lipid conjugates, coined maresin conjugates in tissue regeneration. The formation of these mediators is temporally regulated during acute self-limited infectious-inflammation where they promote the uptake and clearance of apoptotic cells, regulate several aspects of the tissue repair and regeneration, and display potent anti-nociceptive actions.Studies in the authorsβ laboratories were supported by a Sir Henry
Dale Fellowship jointly funded by the Wellcome Trust and the
Royal Society (Grant number: 107613/Z/15/Z), funding from the
European Research Council (ERC) under the European Unionβs
Horizon 2020 research and innovation program (Grant number:
677542), the Barts Charity (Grant number: MGU0343) to JD, and
National Institutes of Health (grant numbers R01GM38765 and
P01GM095467) to CNS
Novel n-3 Docosapentaneoic Acid-Derived Pro-resolving Mediators Are Vasculoprotective and Mediate the Actions of Statins in Controlling Inflammation
βThis is a post-peer-review, pre-copyedit version of a chapter published in Advances in Experimental Medicine and Biology book series (AEMB, volume 1161). The final publication is available athttps://doi.org/10.1007/978-3-030-21735-8_7
Proresolving lipid mediators resolvin D1, resolvin D2, and maresin 1 are critical in modulating T cell responses.
Resolution of inflammation is a finely regulated process mediated by specialized proresolving lipid mediators (SPMs), including docosahexaenoic acid (DHA)-derived resolvins and maresins. The immunomodulatory role of SPMs in adaptive immune cells is of interest. We report that D-series resolvins (resolvin D1 and resolvin D2) and maresin 1 modulate adaptive immune responses in human peripheral blood lymphocytes. These lipid mediators reduce cytokine production by activated CD8(+) T cells and CD4(+) T helper 1 (TH1) and TH17 cells but do not modulate T cell inhibitory receptors or abrogate their capacity to proliferate. Moreover, these SPMs prevented naΓ―ve CD4(+) T cell differentiation into TH1 and TH17 by down-regulating their signature transcription factors, T-bet and Rorc, in a mechanism mediated by the GPR32 and ALX/FPR2 receptors; they concomitantly enhanced de novo generation and function of Foxp3(+) regulatory T (Treg) cells via the GPR32 receptor. These results were also supported in vivo in a mouse deficient for DHA synthesis (Elovl2(-/-)) that showed an increase in TH1/TH17 cells and a decrease in Treg cells compared to wild-type mice. Additionally, either DHA supplementation in Elovl2(-/-) mice or in vivo administration of resolvin D1 significantly reduced cytokine production upon specific stimulation of T cells. These findings demonstrate actions of specific SPMs on adaptive immunity and provide a new avenue for SPM-based approaches to modulate chronic inflammation.This work was supported by Fondazione Italiana Sclerosi Multipla (FISM) to V.C.
(grant 2015/R/8) and in part by National Institutes of Health (P01095467 and
GM38765) to C.N.S, by Ministero dellβIstruzione, dellβUniversitΓ e della Ricerca
(PRIN grant 2010β2011) to M.M., and by Ministero della Salute (RF-2011-
02346771) and FISM (grant 2013/R/2) to L.B
Lipid Mediator Metabolomics Via LC-MS/MS Profiling and Analysis.
protocolSolid-phase extraction coupled with liquid chromatography tandem mass spectrometry provides a robust and sensitive approach for the identification and quantitation of specialized pro-resolving mediators (lipoxins, resolvins, protectins, and maresins), their pathway markers and the classic eicosanoids. Here, we provide a detailed description of the methodologies employed for the extraction of these mediators from biological systems, setup of the instrumentation, sample processing, and then the procedures followed for their identification and quantitation
Anesthetics Impact the Resolution of Inflammation
Local and volatile anesthetics are widely used for surgery. It is not known whether anesthetics impinge on the orchestrated events in spontaneous resolution of acute inflammation. Here we investigated whether a commonly used local anesthetic (lidocaine) and a widely used inhaled anesthetic (isoflurane) impact the active process of resolution of inflammation.Using murine peritonitis induced by zymosan and a systems approach, we report that lidocaine delayed and blocked key events in resolution of inflammation. Lidocaine inhibited both PMN apoptosis and macrophage uptake of apoptotic PMN, events that contributed to impaired PMN removal from exudates and thereby delayed the onset of resolution of acute inflammation and return to homeostasis. Lidocaine did not alter the levels of specific lipid mediators, including pro-inflammatory leukotriene B(4), prostaglandin E(2) and anti-inflammatory lipoxin A(4), in the cell-free peritoneal lavages. Addition of a lipoxin A(4) stable analog, partially rescued lidocaine-delayed resolution of inflammation. To identify protein components underlying lidocaine's actions in resolution, systematic proteomics was carried out using nanospray-liquid chromatography-tandem mass spectrometry. Lidocaine selectively up-regulated pro-inflammatory proteins including S100A8/9 and CRAMP/LL-37, and down-regulated anti-inflammatory and some pro-resolution peptides and proteins including IL-4, IL-13, TGF-Γ’ and Galectin-1. In contrast, the volatile anesthetic isoflurane promoted resolution in this system, diminishing the amplitude of PMN infiltration and shortening the resolution interval (Ri) approximately 50%. In addition, isoflurane down-regulated a panel of pro-inflammatory chemokines and cytokines, as well as proteins known to be active in cell migration and chemotaxis (i.e., CRAMP and cofilin-1). The distinct impact of lidocaine and isoflurane on selective molecules may underlie their opposite actions in resolution of inflammation, namely lidocaine delayed the onset of resolution (T(max)), while isoflurane shortened resolution interval (Ri).Taken together, both local and volatile anesthetics impact endogenous resolution program(s), altering specific resolution indices and selective cellular/molecular components in inflammation-resolution. Isoflurane enhances whereas lidocaine impairs timely resolution of acute inflammation
Impaired Phagocytosis in Localized Aggressive Periodontitis: Rescue by Resolvin E1
Resolution of inflammation is an active temporally orchestrated process demonstrated by the biosynthesis of novel proresolving mediators. Dysregulation of resolution pathways may underlie prevalent human inflammatory diseases such as cardiovascular diseases and periodontitis. Localized Aggressive Periodontitis (LAP) is an early onset, rapidly progressing form of inflammatory periodontal disease. Here, we report increased surface P-selectin on circulating LAP platelets, and elevated integrin (CD18) surface expression on neutrophils and monocytes compared to healthy, asymptomatic controls. Significantly more platelet-neutrophil and platelet-monocyte aggregates were identified in circulating whole blood of LAP patients compared with asymptomatic controls. LAP whole blood generates increased pro-inflammatory LTB4 with addition of divalent cation ionophore A23187 (5 Β΅M) and significantly less, 15-HETE, 12-HETE, 14-HDHA, and lipoxin A4. Macrophages from LAP subjects exhibit reduced phagocytosis. The pro-resolving lipid mediator, Resolvin E1 (0.1β100 nM), rescues the impaired phagocytic activity in LAP macrophages. These abnormalities suggest compromised resolution pathways, which may contribute to persistent inflammation resulting in establishment of a chronic inflammatory lesion and periodontal disease progression
Microscale arrays for the profiling of start and stop signals coordinating human-neutrophil swarming.
Neutrophil swarms protect healthy tissues by sealing off sites of infection. In the absence of swarming, microbial invasion of surrounding tissues can result in severe infections. Recent observations in animal models have shown that swarming requires rapid neutrophil responses and well-choreographed neutrophil migration patterns. However, in animal models physical access to the molecular signals coordinating neutrophil activities during swarming is limited. Here, we report the development and validation of large microscale arrays of zymosan-particle clusters for the study of human neutrophils during swarming ex vivo. We characterized the synchronized swarming of human neutrophils under the guidance of neutrophil-released chemokines, and measured the mediators released at different phases of human-neutrophil swarming against targets simulating infections. We found that the network of mediators coordinating human-neutrophil swarming includes start and stop signals, proteolytic enzymes and enzyme inhibitors, as well as modulators of activation of other immune and non-immune cells. We also show that the swarming behavior of neutrophils from patients following major trauma is deficient and gives rise to smaller swarms than those of neutrophils from healthy individuals
Increased 15-PGDH expression leads to dysregulated resolution responses in stromal cells from patients with chronic tendinopathy
S.G.D. is a recipient of an Oxford UCB Prize Fellowship in Biomedical Research and also received funding from Arthritis Research UK (grant no: 20506). Arthritis Research UK also supported UO (program grant 20522). J.D. received funding from the European Research Council (ERC) under the European Unionβs Horizon 2020 research and innovation programme (grant no: 677542) and the Barts Charity (grant no: MGU0343). J.D. is also supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (grant 107613/Z/15/Z). Research at NDORMS, University of Oxford is supported through the National Institute for Health Research (NIHR) Oxford Musculoskeletal Biomedical Research Centre (BRC)
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