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Background and purpose Recent biochemical and pharmacological studies have reported that in several tissues and cell types, microsomal PGE2 synthase (mPGES) and PPAR-γ expression are modulated by a variety of inflammatory factors and stimuli. Considering that very little is known about the biological effects promoted by IL-17 in the context of mPGES-1/PPAR-γ modulation, we sought to investigate the contribution of this unique cytokine on this integrated pathway during the onset of inflammation. Experimental approach We evaluated effects of PF 9184 (mPGES-1 inhibitor) and troglitazone (PPAR-γ agonist) in vitro, using the mouse macrophage cell line J774A.1. In vivo, the dorsal air pouch model in CD1 mice was used, and inflammatory infiltrates were analysed by flow cytometry. Locally produced cyto-chemokines and PGs were assessed using elisa assays. Western blots were also employed to determine the activity of various enzymes involved in downstream signalling pathways. Key results PF 9184 and troglitazone, in a time- and dose-dependent manner, modulated leukocyte infiltration, myeloperoxidase activity, and the expression of COX-2/mPGES-1, NF-кB/IкB-α, and mPTGDS-1/PPAR-γ, induced by IL-17. Moreover, both PF 9184 and troglitazone modulated PG (PGE2 , PGD2 , and PGJ2 ) production, the expression of different pro-inflammatory cyto-chemokines, and the recruitment of inflammatory monocytes, in response to IL-17. Conclusions and implications Our data suggest that IL-17 may constitute a specific modulator of inflammatory monocytes during later phases of the inflammatory response. The results of this study show, for the first time, that the IL-17/mPGES-1/PPAR-γ pathway could represent a potential therapeutic target for inflammatory-based and immune-mediated diseases.

Inflammation plays a key role in the pathogenesis of several chronic diseases. The urokinase plasminogen activator receptor (uPAR) exerts a plethora of functions in both physiological and pathological processes, including inflammation. In this study, we evaluated the anti-inflammatory effect of a novel peptide ligand of uPAR, UPARANT, in different animal models of inflammation. Rats and mice were divided in different groups (n = 5) for single or repeated administration of vehicle (9% DMSO in 0.9% NaCl), UPARANT (6, 12 and 24 mg/kg) or dexamethasone (2 mg/kg). Animals were subjected to carrageenan-induced paw oedema or zymosan-induced peritonitis. UPARANT effects were tested on: (1) the carrageenan-induced paw oedema volume, (2) the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the nitrite/nitrate (NOx) levels in the paw exudates, (3) cells recruitment into the peritoneal cavity after zymosan injection and (4) NOx levels in the peritoneal lavage. UPARANT (12 and 24 mg/kg) reduced inflammation in both experimental paradigms. Analysis of pro-inflammatory enzymes revealed that administration of UPARANT reduced iNOS, COX2 and NO over-production. Our study provides a solid evidence that UPARANT reduces the severity of inflammation in diverse animal models, thus representing a novel anti-inflammatory drug with potential advantages with respect to the typical steroidal agents.

Nociceptors are receptors specifically involved in detecting a tissue damage and transducing it in an electrical signal. Nociceptor activation provoked by any kind of acute lesion is related to the release of several mediators of inflammation, within the framework of a process defined as "peripheral sensitization". This results in an exaggerated response to the painful stimulus, clinically defined as "primary hyperalgesia". The concept of "neuroplasticity" may explain the adaptive mechanisms carried out by the Nervous System in relation to a "harmful" damage; also, neuroplasticity mechanisms are also fundamental for rehabilitative intervention protocols. Here we review several studies that addressed the role of different receptors and ionic channels discovered on nociceptor surface and their role in pain perception. The changes in expression, distribution and functioning of receptors and ionic channels are thought to be a part of the neuroplasticity property, through which the Nervous System constantly adapts to external stimuli. Moreover, some of the reviewed mediators are also been associated to "central sensitization", a process that results in pain chronicization when the painful stimulation is particularly prolonged or intense, and lastly leads to the memorization of the uncomfortable painful perception. This article is protected by copyright. All rights reserved.

// Elisabetta Panza 1, * , Paola De Cicco 1, * , Giuseppe Ercolano 1 , Chiara Armogida 1 , Giosue Scognamiglio 2 , Anna Maria Anniciello 2 , Gerardo Botti 2 , Giuseppe Cirino 1 , Angela Ianaro 1 1 Department of Pharmacy, University of Naples Federico II, Naples Italy 2 Department of Experimental Oncology, National Cancer Institute, G. Pascale, Naples, Italy * These authors have contributed equally to this work Correspondence to: Giuseppe Cirino, email: cirino@unina.it Keywords: malignant melanoma, cyclooxygenase-2, COX-2 -/- mice, progression free survival, metastasis Received: April 11, 2016 Accepted: July 19, 2016 Published: August 01, 2016 ABSTRACT The possible correlation between cyclooxygenase-2 (COX-2) expression and disease progression in melanoma is still a matter of debate. Analysis of COX-2 expression in 45 lymph node melanoma metastases demonstrates a significant correlation between the percent of expression and progression free survival (PFS). A positive COX-2 expression ≥10% (COX-2 high ), as opposite to a positive expression ≤9% (COX-2 low ), translated into a striking significant reduction of PFS of about 3 years. The reduction in PFS correlated neither with BRAF V600E nor with NRAS Q61 expression in the analyzed samples. This concept was reinforced by the finding that tumour development in COX-2 -/- mice was almost blunted. Similarly, inhibition of COX-2 protein expression in human melanoma cell lines, by using siRNAs technology as well as selective inhibition of COX-2 activity by celecoxib, reduced cellular proliferation and invasiveness. In conclusion we show that COX-2 high is a negative prognostic factor in metastatic melanoma. Our study also clarifies that the uncertainty about the role of COX-2 in metastatic malignant melanoma, found in the current relevant literature, is probably due to the fact that a threshold in COX-2 expression has to be reached in order to impact on cancer malignancy. Our findings suggest that COX-2 expression may become an useful diagnostic tool in defining melanoma malignancy as well as argue for a possible therapeutic use of NSAID as add on therapy in selected cases.

In humans, two main metabolic enzymes synthesize hydrogen sulfide (H2 S): cystathionine γ lyase (CSE) and cystathionine β synthase (CBS). A third enzyme, 3-mercaptopyruvate sulfurtransferase (3-MST), synthesizes H2 S in the presence of the substrate 3-mercaptopyruvate (3-MP). The immunohistochemistry analysis performed on human melanoma samples demonstrated that CSE expression was highest in primary tumors, decreased in the metastatic lesions and was almost silent in non-lymph node metastases. The primary role played by CSE was confirmed by the finding that the overexpression of CSE induced spontaneous apoptosis of human melanoma cells. The same effect was achieved using different H2 S donors, the most active of which was diallyl trisulfide (DATS). The main pro-apoptotic mechanisms involved were suppression of nuclear factor-κB activity and inhibition of AKT and extracellular signal-regulated kinase pathways. A proof of concept was obtained in vivo using a murine melanoma model. In fact, either l-cysteine, the CSE substrate, or DATS inhibited tumor growth in mice. In conclusion, we have determined that the l-cysteine/CSE/H2 S pathway is involved in melanoma progression.

Nutritional research has shifted recently from alleviating nutrient deficiencies to chronic disease prevention. We investigated the activity of indicaxanthin, a bioavailable phytochemical of the betalain class from the edible fruit of Opuntia ficus-indica (L. Miller) in a rat model of acute inflammation. Rat pleurisy was achieved by injection of 0.2 mL of l-carrageenin in the pleural cavity, and rats were killed 4, 24, and 48 h later; exudates were collected to analyze inflammatory parameters, such as nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1b (IL-1b), and tumor necrosis factor-a (TNF-a); cells recruited in pleura were analyzed for cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) expression, and nuclear factor k-light-chain-enhancer of activated B cells (NF-kB) activation. Indicaxanthin (0.5, 1, or 2 mmol/kg), given orally before carrageenin, time- and dose-dependently, reduced the exudate volume (up to 70%) and the number of leukocytes recruited in the pleural cavity (up to 95%) at 24 h. Pretreatment with indicaxanthin at 2 mmol/kg inhibited the carrageenin-induced release of PGE2 (91.4%), NO (67.7%), IL-1b (53.6%), and TNF-a (71.1%), and caused a decrease of IL-1b (34.5%), TNF-a (81.6%), iNOS (75.2%), and COX2 (87.7%) mRNA, as well as iNOS (71.9%) and COX-2 (65.9%) protein expression, in the recruited leukocytes. Indicaxanthin inhibited time- and dose- dependently the activation of NFkB, a key transcription factor in the whole inflammatory cascade. A pharmacokinetic study with a single 2 mmol/kg oral administration showed a maximum 0.22 6 0.02 mmol/L (n = 15) plasma concentration of indicaxanthin, with a half-life of 1.15 6 0.11 h. When considering the high bioavailability of indicaxanthin in humans, our findings suggest that this dietary pigment has the potential to improve health and prevent inflammation-based disorders. J. Nutr. 144: 185–192, 2014.

Here we have characterized perthamide C, a cyclopeptide from a Solomon Lithistid sponge Theonella swinhoei, which displays an anti-inflammatory/immunomodulatory activity. The study has been performed using the carragenan-induced mouse paw edema that displays an early (0–6 h) and a late phase (24–96 h). Perthamide C significantly inhibits neutrophils infiltration in tissue both in the early and late phases. This effect was coupled to a reduced expression of the endothelial nitric oxide synthase (eNOS) in the early phase while cyclooxygenase-1 and 2 (COX-1, COX-2), and inducible NOS (iNOS) expression were unaffected. In the late phase perthamide C reduced expression of both NOS isoforms without affecting COXs expression. This peculiar selectivity toward the two enzymes deputed to produce NO lead us to investigate on a possible action of perthamide C on lymphocytes infiltration and activation. We found that perthamide C inhibited the proliferation of peripheral lymphocytes, and that this effect was secondary to its metabolic activation in vivo. Indeed, in vitro perthamide C did not inhibit proliferation as opposite to its metabolite perthamide H. In conclusion, perthamide C selectively interferes with NO generation triggered by either eNOS or iNOS without affecting either COX-1 or COX-2. This in turn leads to modulation of the inflammatory response through a reduction of vascular permeability, neutrophil infiltration as well as lymphocyte proliferation.

Ring strain causes planar chirality in tedarenes A and B, two cyclic diarylheptanoids isolated from the marine sponge Tedania ignis. In both molecules, the chiral plane is an olefinic system, which is very rare among natural products. In tedarene A (1), interconversion is too fast to allow isolation of the enantiomeric atropisomers but still slow enough to cause coalescence of some (1)H and (13)C NMR signals at room temperature. In tedarene B (2), which also shows stable central and axial chirality, the two planar diastereomers are in slow equilibrium. Tedarene B is the smallest natural product with central, axial, and planar chirality in the same simple molecule. The identification of planar chirality as the difference between its conformational isomers allowed the use of theoretical prediction of the CD spectrum to determine the absolute configuration of the stereogenic carbon C-9 as well as of the biphenyl chiral axis.

Chemical analysis of the Indonesian soft coral Sinularia sp. (order Alcyonacea, family Alcyoniidae) afforded a known glucosylcerebroside of the sarcoehrenoside-type and sinularioside (2), a new naturally triacetylated glycolipid containing two α-D-arabinopyranosyl residues and a myristyl alcohol unit. Their complete stereostructures were solved by interpretation of MS and NMR data along with CD analysis of degradation products. Sinularioside proved to moderately inhibit LPS-induced NO release, providing interesting clues into the poorly understood structure-activity relationships for anti-inflammatory glycolipids.

Changes in the expression of potassium channels regulate skeletal muscle development. The purpose of this study was to investigate the expression profile and pharmacological role of K(v)7 voltage-gated potassium channels in skeletal muscle differentiation, proliferation, and survival after myotoxic insults. Transcripts for all K(v)7 genes (K(v)7.1-K(v)7.5) were detected by polymerase chain reaction (PCR) and/or real-time PCR in murine C(2)C(12) myoblasts; K(v)7.1, K(v)7.3, and K(v)7.4 transcripts were up-regulated after myotube formation. Western blot experiments confirmed K(v)7.2, K(v)7.3, and K(v)7.4 subunit expression, and the up-regulation of K(v)7.3 and K(v)7.4 subunits during in vitro differentiation. In adult skeletal muscles from mice and humans, K(v)7.2 and K(v)7.3 immunoreactivity was mainly localized at the level of intracellular striations positioned between ankyrinG-positive triads, whereas that of K(v)7.4 subunits was largely restricted to the sarcolemmal membrane. In C(2)C(12) cells, retigabine (10 microM), a specific activator of neuronally expressed K(v)7.2 to K(v)7.5 subunits, reduced proliferation, accelerated myogenin expression, and inhibited the myotoxic effect of mevastatin (IC(50) approximately 7 microM); all these effects of retigabine were prevented by the K(v)7 channel blocker 10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone (XE-991) (10 muM). These data collectively highlight neural K(v)7 channels as significant pharmacological targets to regulate skeletal muscle proliferation, differentiation, and myotoxic effects of drugs.

In this study, the functional consequences of the pharmacological modulation of the M-current (I(KM)) on cytoplasmic Ca(2+) intracellular Ca(2+)concentration ([Ca(2+)](i)) changes and excitatory neurotransmitter release triggered by various stimuli from isolated rat cortical synaptosomes have been investigated. K(v)7.2 immunoreactivity was identified in pre-synaptic elements in cortical slices and isolated glutamatergic cortical synaptosomes. In cerebrocortical synaptosomes exposed to 20 mM [K(+)](e), the I(KM) activator retigabine (RT, 10 microM) inhibited [(3)H]D-aspartate ([(3)H]D-Asp) release and caused membrane hyperpolarization; both these effects were prevented by the I(KM) blocker XE-991 (20 microM). The I(KM) activators RT (0.1-30 microM), flupirtine (10 microM) and BMS-204352 (10 microM) inhibited 20 mM [K(+)](e)-induced synaptosomal [Ca(2+)](i) increases; XE-991 (20 microM) abolished RT-induced inhibition of depolarization-triggered [Ca(2+)](i) transients. The P/Q-type voltage-sensitive Ca(2+)channel (VSCC) blocker omega-agatoxin IVA prevented RT-induced inhibition of depolarization-induced [Ca(2+)](i) increase and [(3)H]D-Asp release, whereas the N-type blocker omega-conotoxin GVIA failed to do so. Finally, 10 microM RT did not modify the increase of [Ca(2+)](i) and the resulting enhancement of [(3)H]D-Asp release induced by [Ca(2+)](i) mobilization from intracellular stores, or by store-operated Ca(2+)channel activation. Collectively, the present data reveal that the pharmacological activation of I(KM) regulates depolarization-induced [(3)H]D-Asp release from cerebrocortical synaptosomes by selectively controlling the changes of [Ca(2+)](i) occurring through P/Q-type VSCCs.

KCNQ2 and KCNQ3 subunits encode for the muscarinic-regulated current (I(KM)), a sub-threshold voltage-dependent K+ current regulating neuronal excitability. In this study, we have investigated the involvement of I(KM) in dopamine (DA) release from rat striatal synaptosomes evoked by elevated extracellular K+ concentrations ([K+]e) and by muscarinic receptor activation. [3H]dopamine ([3H]DA) release triggered by 9 mmol/L [K+]e was inhibited by the I(KM) activator retigabine (0.01-30 micromol/L; Emax = 54.80 +/- 3.85%; IC50 = 0.50 +/- 0.36 micromol/L). The I(KM) blockers tetraethylammonium (0.1-3 mmol/L) and XE-991 (0.1-30 micromol/L) enhanced K+-evoked [3H]DA release and prevented retigabine-induced inhibition of depolarization-evoked [3H]DA release. Retigabine-induced inhibition of K+-evoked [3H]DA release was also abolished by synaptosomal entrapment of blocking anti-KCNQ2 polyclonal antibodies, an effect prevented by antibody pre-absorption with the KCNQ2 immunizing peptide. Furthermore, the cholinergic agonist oxotremorine (OXO) (1-300 micromol/L) potentiated 9 mmol/L [K+]e-evoked [3H]DA release (Emax = 155 +/- 9.50%; EC50 = 25 +/- 1.80 micromol/L). OXO (100 micromol/L)-induced [3H]DA release enhancement was competitively inhibited by pirenzepine (1-10 nmol/L) and abolished by the M3-preferring antagonist 4-diphenylacetoxy N-methylpiperidine methiodide (1 micromol/L), but was unaffected by the M1-selective antagonist MT-7 (10-100 nmol/L) or by Pertussis toxin (1.5-3 microg/mL), which uncouples M2- and M4-mediated responses. Finally, OXO-induced potentiation of depolarization-induced [3H]DA release was not additive to that produced by XE-991 (10 micromol/L), was unaffected by retigabine (10 micromol/L), and was abolished by synaptosomal entrapment of anti-KCNQ2 antibodies. Collectively, these findings indicate that, in rat striatal nerve endings, I(KM) channels containing KCNQ2 subunits regulate depolarization-induced DA release and that I(KM) suppression is involved in the reinforcement of depolarization-induced DA release triggered by the activation of pre-synaptic muscarinic heteroreceptors.