28 research outputs found
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 naĂŻve 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 dellâIstruzione, dellâUniversitĂ e della Ricerca
(PRIN grant 2010â2011) to M.M., and by Ministero della Salute (RF-2011-
02346771) and FISM (grant 2013/R/2) to L.B
Changes in the expression of extracellular regulated kinase (ERK 1/2) in the R6/2 mouse model of Huntington's disease after phosphodiesterase IV inhibition
The mitogen-activated protein kinases (MAPKs) superfamily comprises three major signaling pathways: the extracellular signal-regulated protein kinases (ERKs), the c-Jun N-terminal kinases or stress-activated protein kinases (JNKs/SAPKs) and the p38 family of kinases.ERK 1/2 signaling has been implicated in a number of neurodegenerative disorders, including Huntington's disease (HD). Phosphorylation patterns of ERK 1/2 and JNK are altered in cell models of HD. In this study, we aimed at studying the correlations between ERK 1/2 and the neuronal vulnerability to HD degeneration in the R6/2 transgenic mouse model of HD. Single and double-label immunofluorescence for phospho-ERK (pERK, the activated form of ERK) and for each of the striatal neuronal markers were employed on perfusion-fixed brain sections from R6/2 and wild-type mice. Moreover, Phosphodiesterase 4 inhibition through rolipram was used to study the effects on pERK expression in the different types of striatal neurons. We completed our study with western blot analysis. Our study shows that pERK levels increase with age in the medium spiny striatal neurons and in the parvalbumin interneurons, and that rolipram counteracts such increase in pERK. Conversely, cholinergic and somatostatinergic interneurons of the striatum contain higher levels of pERK in the R6/2 mice compared to the controls. Rolipram induces an increase in pERK expression in these interneurons. Thus, our study confirms and extends the concept that the expression of phosphorylated ERK 1/2 is related to neuronal vulnerability and is implicated in the pathophysiology of cell death in HD. (C) 2012 Elsevier Inc. All rights reserved
Effects of Rare Phytocannabinoids on the Endocannabinoid System of Human Keratinocytes
The decriminalization and legalization of cannabis has paved the way for investigations into the potential of the use of phytocannabinoids (pCBs) as natural therapeutics for the treatment of human diseases. This growing interest has recently focused on rare (less abundant) pCBs that are non-psychotropic compounds, such as cannabigerol (CBG), cannabichromene (CBC), Î9-tetrahydrocannabivarin (THCV) and cannabigerolic acid (CBGA). Notably, pCBs can act via the endocannabinoid system (ECS), which is involved in the regulation of key pathophysiological processes, and also in the skin. In this study, we used human keratinocytes (HaCaT cells) as an in vitro model that expresses all major ECS elements in order to systematically investigate the effects of CBG, CBC, THCV and CBGA. To this end, we analyzed the gene and protein expression of ECS components (receptors: CB1, CB2, GPR55, TRPV1 and PPARα/Îł/ÎŽ; enzymes: NAPE-PLD, FAAH, DAGLα/ÎČ and MAGL) using qRT-PCR and Western blotting, along with assessments of their functionality using radioligand binding and activity assays. In addition, we quantified the content of endocannabinoid(-like) compounds (AEA, 2-AG, PEA, etc.) using UHPLC-MS/MS. Our results demonstrated that rare pCBs modulate the gene and protein expression of distinct ECS elements differently, as well as the content of endocannabinoid(-like) compounds. Notably, they all increased CB1/2 binding, TRPV1 channel stimulation and FAAH and MAGL catalytic activity. These unprecedented observations should be considered when exploring the therapeutic potential of cannabis extracts for the treatment of human skin diseases
Lipid signalling in human immune response and bone remodelling under microgravity
Since the first Apollo mission in 1969, microgravity has been linked to many alterations of astronauts' physiology, among which immunosuppression, altered inflammation and bone loss represent relevant examples. In the past 40 years, extensive investigations have been conducted in order to characterize the molecular mechanisms driving the alterations caused by prolonged weightlessness on human health. However, almost all studies eluded the role played by bioactive lipids, a vastly heterogeneous class of endogenous molecules, which, under normal conditions, control immune and bone homeostasis. This is somewhat surprising, because it is widely accepted that pathological derangement of the production or signalling of these endogenous compounds leads to the onset and/or progression of numerous diseases. In particular, eicosanoids and endocannabinoids are known to play a role in immune responses and bone remodelling. Both classes represent the only lipids as yet investigated in Space, and are increasingly recognised as promising therapeutic candidates to combat different human disorders. This review summarizes evidence gathered in the past two decades on the changes in these two pivotal lipid signalling systems, through both simulated and authentic weightlessness (i.e., on board the International Space Station and in parabolic flights)
Role of Specialized Pro-Resolving Mediators in Neuropathic Pain
Inflammation and neuroinflammation are critical mechanisms in the generation of neuropathic pain that is experienced in several chronic diseases. The aberrant inflammation that triggers this pathophysiologic process can be tracked down to an exacerbated immune response, which establishes a vicious cycle and continuously recruits inflammatory cells by inducing chronic tissue damage. Recently, impairment of the cellular and molecular machinery orchestrated by specialized pro-resolving mediators (SPMs)âi.e., endogenous lipids termed resolvins, protectins, maresins, and lipoxins that confine the inflammatory cascades in space and time during the âresolution of inflammationââhas emerged as a crucial event in the derangement of the inflammatory homeostasis and the onset of chronic inflammation and pain. Indeed, a deviant inflammatory response that is not adequately controlled by the resolution network leads to the overproduction of pro-inflammatory eicosanoids that, opposite to SPMs, lead to neuropathic pain. Interestingly, in the last two decades convincing evidence has demonstrated that SPMs antagonize the in vivo activity of pro-inflammatory eicosanoids and, overall, exert potent anti-hyperalgesic effects in a number of pain-associated paradigms of disease, such as arthritis and chemotherapy-induced peripheral neuropathy, as well as in many experimental models of pain like mechanical allodynia, chemical pain, heat hypersensitivity and phase 1 and 2 inflammatory pain. Of note, accumulated evidence supports a synergy between SPMs and other signalling pathways, such as those mediated by transient receptor potential (TRP) channels and those triggered by opioid receptors, suggesting that the cascade of events where inflammation and pain perception take part might be ways more intricated than originally expected. Here, we aim at presenting a state-of-the-art view of SPMs, their metabolism and signalling, in the context of cellular and molecular pathways associated to neuropathic pain
A metabolic investigation of arterialized venous flaps in rabbits using mass spectrometryâbased metabolomics
Bioactive lipids, inflammation and chronic diseases
Endogenous bioactive lipids are part of a complex network that modulates a plethora of cellular and molecular processes involved in health and disease, of which inflammation represents one of the most prominent examples. Inflammation serves as a well-conserved defence mechanism, triggered in the event of chemical, mechanical or microbial damage, that is meant to eradicate the source of damage and restore tissue function. However, excessive inflammatory signals, or impairment of pro-resolving/anti-inflammatory pathways leads to chronic inflammation, which is a hallmark of chronic pathologies. All main classes of endogenous bioactive lipids â namely eicosanoids, specialized pro-resolving lipid mediators, lysoglycerophopsholipids and endocannabinoids â have been consistently involved in the chronic inflammation that characterises pathologies such as cancer, diabetes, atherosclerosis, asthma, as well as autoimmune and neurodegenerative disorders and inflammatory bowel diseases. This review gathers the current knowledge concerning the involvement of endogenous bioactive lipids in the pathogenic processes of chronic inflammatory pathologies
A web platform for integrated vulnerability assessment and cyber risk management
Cyber risk management is a very important problem for every company connected to the internet. Usually, risk management is done considering only Risk Analysis without connecting it with Vulnerability Assessment, using external and expensive tools. In this paper we present CYber Risk Vulnerability Management (CYRVM)-a custom-made software platform devised to simplify and improve automation and continuity in cyber security assessment. CYRVM's main novelties are the combination, in a single and easy-to-use Web-based software platform, of an online Vulnerability Assessment tool within a Risk Analysis framework following the NIST 800-30 Risk Management guidelines and the integration of predictive solutions able to suggest to the user the risk rating and classification
Systemic delivery of recombinant Brain Derived Neurotrophic Factor (BDNF) in the R6/2 mouse model of Huntington's disease
Loss of huntingtin-mediated BDNF gene transcription has been shown to occur in HD and thus contribute to the degeneration of the striatum. Several studies have indicated that an increase in BDNF levels is associated with neuroprotection and amelioration of neurological signs in animal models of HD. In a recent study, an increase in BDNF mRNA and protein levels was recorded in mice administered recombinant BDNF peripherally. Chronic, indwelling osmotic mini-pumps containing either recombinant BDNF or saline were surgically placed in R6/2 or wild-type mice from 4 weeks of age until euthanasia. Neurological evaluation (paw clasping, rotarod performance, locomotor activity in an open field) was performed. After transcardial perfusion, histological and immunohistochemical studies were performed. We found that BDNF- treated R6/2 mice survived longer and displayed less severe signs of neurological dysfunction than the vehicle treated ones. Primary outcome measures such as brain volume, striatal atrophy, size and morphology of striatal neurons, neuronal intranuclear inclusions and microglial reaction confirmed a neuroprotective effect of the compound. BDNF was effective in increasing significantly the levels of activated CREB and of BDNF the striatal spiny neurons. Moreover, systemically administered BDNF increased the synthesis of BDNF as demonstrated by RT-PCR, and this might account for the beneficial effects observed in this model
Nuclear localization of phosphodiesterase 10A (PDE10A) in the R6/2 mouse striatal interneurons
Introduction: Cyclic nucleotides play an important role as second messengers in the CNS. Intracellular concentrations of cAMP and cGMP are modulated by the rate of degradation by a variety of phosphodiesterases (PDEs). PDE10A is the single member of one of the newest PDE gene families. PDE10A has been observed in the brain mostly in the striatal projec- tion neurons [1]. However, we have previously observed [unpublished data], in the striatum, a number of PDE10 immunoreactive neurons that were not projection neurons. Methods: R6/2 mice and their wild type littermates were sacrificed at 5,
9, 13 weeks of age, and single and double label immunohistochemis- try were performed to identify the different neuronal subtypes of the striatum (medium spiny, choliner- gic, parvalbuminergic, somatos- tatinergic). Results: PDE10A was observed in all subtypes of striatal neurons. In the spiny projection neurons, PDE10A localized in the cytoplasm, whereas in the striatal interneurons, regardless of the sub- type, PDE10A displayed a clearly nuclear localization. This was true both for the wild type and for the R6/2 mice. Conclusions: Our study demonstrates that PDE10A is con- tained not only in the medium spiny neurons, but also in the striatal in- terneurons. Moreover, the different compartmentalization might be ex- plained by a different activity exert- ed by PDE10A between projection neurons and interneurons.
Reference
[1] Seeger TF, Bartlett B, Coskran TM, Culp JS, James LC, Krull DL, Lanfear J, Ryan AM, Schmidt CJ, Strick CA, Var- ghese AH, Williams RD, Wylie PG, Men- niti FS. Immunohistochemical localiza- tion of PDE10A in the rat brain. Brain Res. 2003; 985: 113-126