174 research outputs found
HelixComplex snail mucus as a potential technology against O3 induced skin damage
Mucus form H. aspersa muller has been reported to have several therapeutic proprieties, such as antimicrobial activity, skin protection and wound repair. In this study, we have analyzed H. aspersa mucus (Helixcomplex) bio-adhesive efficacy and its defensive properties against the ozone (O3) (0.5 ppm for 2 hours) exposure in human keratinocytes and reconstructed human epidermis models. Cytotoxicity, tissue morphology and cytokine levels were determined. We confirmed HelixComplex regenerative and bio-adhesive properties, the latter possibly via the characteristic mucopolysaccharide composition. In addition, HelixComplex was able to protect from O3 exposure by preventing oxidative damage and the consequent pro-inflammatory response in both 2D and 3D models. Based on this study, it is possible to suggest HelixComplex as a potentially new protective technology against pollution induced skin damage
Plasticity of the Anemonia viridis microbiota in response to different levels of combined anthropogenic and environmental stresses
Despite their recognized primary importance, marine coastal ecosystems around the globe are currently under threat, being subject to continuous local and global anthropogenic stressors. In this frame, understanding the response of coastal habitat-forming species to multiple stressors and their resilience is fundamental for the sustainable management of coastal ecosystems. In the present study, to provide some glimpses in this direction, we explored the response of the Anemonia viridis-associated microbiota to the combined anthropogenic stressors, which typically affect touristic hotspots at Mediterranean coastal sites. To this aim, two case studies have been carried out, the first in the Riccione coastal site (Italy, Center Mediterranean) and the second at Cap de Creus (Spain, North-western Mediterranean), where the A. viridis microbiota was assessed under the conditions of both high and low anthropogenic pressure. According to our findings, the A. viridis microbiota showed a relevant degree of plasticity in response to combined anthropogenic and environmental stressors, with changes that also mirrored variations in the surrounding seawater, thus indicating a close connection with the environment, from which potential symbiotic partners are selected. However, this potentially adaptive process also has a limitation, as observed in the highly anthropogenic impact site of Cap de Creus, where A. viridis-associated microbiota appeared completely unstructured, as demonstrated by an increased dispersion according to the Anna Karenina principle. This raises the question about the resilience of the A. viridis-associated microbiota under combined climate and anthropogenic threats, as well as of the anthropogenic factors driving the observed dysbiosis changes
Pharmacological modulation of mitochondrial calcium uniporter controls lung inflammation in cystic fibrosis
Mitochondria physically associate with the endoplasmic reticulum to coordinate interorganelle calcium transfer and regulate fundamental cellular processes, including inflammation. Deregulated endoplasmic reticulum–mitochondria cross-talk can occur in cystic fibrosis, contributing to hyperinflammation and disease progression. We demonstrate that Pseudomonasaeruginosainfection increases endoplasmic reticulum–mitochondria associations in cystic fibrosis bronchial cells by stabilizing VAPB-PTPIP51 (vesicle-associated membrane protein–associated protein B–protein tyrosine phosphatase interacting protein 51) tethers, affecting autophagy. Impaired autophagy induced mitochondrial unfolding protein response and NLRP3 inflammasome activation, contributing to hyperinflammation. The mechanism by which VAPB-PTPIP51 tethers regulate autophagy in cystic fibrosis involves calcium transfer via mitochondrial calcium uniporter. Mitochondrial calcium uniporter inhibition rectified autophagy and alleviated the inflammatory response in vitro and in vivo, resulting in a valid therapeutic strategy for cystic fibrosis pulmonary disease
Structure of the nociceptin/orphanin FQ receptor in complex with a peptide mimetic
Members of the Opioid Receptor (OR) family of G protein-coupled receptors (GPCRs) are found throughout the peripheral and central nervous system where they play key roles in nociception and analgesia. Unlike the classical ORs, δ–OR, κ–OR,1 and μ-OR,2 which were delineated by pharmacological criteria in the 1970’s and 1980’s, the nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP, aka ORL-1) was discovered relatively recently via molecular cloning and characterization of an orphan GPCR3. Despite its high sequence similarity (~60%) with ORs, NOP has a strikingly distinct pharmacology4,5. Despite high sequence similarity with classical opioid G protein-coupled receptor subtypes, the nociceptin/orphanin FQ (N/OFQ) peptide receptor (NOP) has a distinct biological and pharmacological role, featuring activation by the endogenous peptide N/OFQ, and unique selectivity for exogenous ligands. This study reports the crystal structure of human NOP solved in complex with the peptide mimetic antagonist Banyu Compound-24 (C-24), revealing atomic details of ligand-receptor recognition and selectivity. C-24 mimics the first four N-terminal residues of the NOP-selective peptide antagonist UFP-101, a close derivative of N/OFQ, and provides important clues to binding of these peptides. The X-ray structure also reveals substantial conformational differences in the pocket regions between NOP and the “classical” opioid receptors κ (Ref. 1) and μ (Ref. 2), which are likely due to a small number of residues that vary between the two receptors. The NOP/C-24 structure explains the divergent selectivity profile of NOP and provides a new structural template for the design of NOP ligands
The Fascinating Chemistry of α-Haloamides
The aim of this review is to highlight the rich chemistry of α-haloamides originally mainly used to discover new C−N, C−O and C−S bond forming reactions, and later widely employed in C−C cross-coupling reactions with C(sp3), C(sp2) and C(sp) coupling partners. Radical-mediated transformations of α-haloamides bearing a suitable located unsaturated bond has proven to be a straightforward alternative to access diverse cyclic compounds by means of either radical initiators, transition metal redox catalysis or visible light photoredox catalysis. On the other hand, cycloadditions with α-halohydroxamate-based azaoxyallyl cations have garnered significant attention. Moreover, in view of the important role in life and materials science of difluoroalkylated compounds, a wide range of catalysts has been developed for the efficient incorporation of difluoroacetamido moieties into activated as well as unactivated substrates
Studies of C-terminal naphthoquinone dipeptides as 20S proteasome inhibitors
The ubiquitin proteasome pathway is crucial in regulating many processes in the cell. Modulation of proteasome activities has emerged as a powerful strategy for potential therapies against much important pathologies. In particular, specific inhibitors may represent a useful tool for the treatment of tumors. Here, we report studies of a new series of peptide-based analogues bearing a naphthoquinone pharmacophoric unit at the C-terminal position. Some derivatives showed inhibition in the µM range of the post-acidic-like and chymotrypsin-like active sites of the proteasome
1-Benzyl-N-[3-[spiroisobenzofuran-1(3H), 4′-piperidin-1-yl]propyl]pyrrolidine-2-carboxamide (Compound 24) antagonizes NOP receptor-mediated potassium channel activation in rat periaqueductal gray slices
Nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor, the fourth member of opioid receptor family, shares
60–70% homology with traditional opioid receptors but displays little affinity for opioids. This receptor was
implicated in many neurological functions and its functional heterogeneity has been proposed. Therefore, it is
imperative to develop and characterize new ligands for NOP receptors. 1-Benzyl-N-[3-[spiroisobenzofuran-1
(3H),4′-piperidin-1-yl]propyl]pyrrolidine-2-carboxamide (Compound 24) is a new non-peptide ligand of
NOP receptor having antagonistic actions in cloned and peripheral NOP receptors. In this study, we
quantitatively characterized its effect on the native NOP receptors in the midbrain slices containing
ventrolateral periaqueductal gray (vlPAG), a region with dense NOP receptors and involved in pain regulation.
In vlPAG neurons, N/OFQ induced G-protein-coupled inwardly rectifying potassium (GIRK) current through
NOP receptors. Compound 24, at 0.3–10 μM, attenuated N/OFQ-induced GIRK current concentrationdependently.
The antagonistic potency of Compound 24 in vlPAG neurons (IC50: 2.6±0.6 μM) was, however,
lower than that obtained in mouse vas deferens preparations or expressed human NOP receptors. The
action kinetic of Compound 24 was slower than [Nphe1, Arg14, Lys15]N/OFQ-NH2 (UFP-101), a peptide
antagonist, in the same preparation. Compound 24 had no intrinsic agonistic activity at NOP receptors at the
concentration up to 10 μM. However, at concentrations higher than 3 μM, it also attenuated the GIRK current
induced by [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin, a mu-opioid receptor agonist. It is concluded that
Compound 24 acts as a pure antagonist at the native NOP receptors in the vlPAG with moderate potency and
selectivity
Enzymatic esterification as potential strategy to enhance the sorbic acid behavior as food and beverage preservative
Sorbic acid is the most commonly used preservative in the food industry. The antimicrobial inhibition of sorbic acid could be influenced by its lipophilic nature, which reduces its use in hydrophilic food formulations. Reactions between sorbic acid and glycerol catalyzed by lipases were studied in order to develop a novel sorbic acid derivate with a promising hydrophilic profile. The esterification reaction between sorbic acid and glycerol in a solvent-free system were performed with an immobilized lipase B from Candida antarctica (CALB). The glycerol sorbate product has been tested against S. griseus bacterium and Saccharomyces cerevisiae yeast. Results indicate that the esterification of sorbic acid with glycerol does improve its antimicrobial properties against Saccharomyces cerevisie. The reported results demonstrate that esterification can be used as a strategy to improve the antimicrobial activity of sorbic acid
Antinociceptive action of NOP and opioid receptor agonists in the mouse orofacial formalin test
Nociceptin/orphanin FQ (N/OFQ) modulates several biological functions, including pain transmission via selective activation of a specific receptor named NOP. The aim of this study was the investigation of the antinociceptive properties of NOP agonists and their interaction with opioids in the trigeminal territory. The orofacial formalin (OFF) test in mice was used to investigate the antinociceptive potential associated to the activation of NOP and opioid receptors. Mice subjected to OFF test displayed the typical biphasic nociceptive response and sensitivity to opioid and NSAID drugs. Mice knockout for the NOP gene displayed a robust pronociceptive phenotype. The NOP selective agonist Ro 65-6570 (0.1-1mgkg(-1)) and morphine (0.1-10mgkg(-1)) elicited dose dependent antinociceptive effects in the OFF with the alkaloid showing larger effects; the isobologram analysis of their actions demonstrated an additive type of interaction. The mixed NOP/opioid receptor agonist cebranopadol elicited potent (0.01-0.1mgkg(-1)) and robust antinociceptive effects. In the investigated dose range, all drugs did not modify the motor performance of the mice in the rotarod test. Collectively the results of this study demonstrated that selective NOP agonists and particularly mixed NOP/opioid agonists are worthy of development as innovative drugs to treat painful conditions of the trigeminal territory
Synthesis and biological properties of C-terminal vinyl ketone pseudotripeptides
The ubiquitin-proteasome pathway responsible for the turnover of many cellular proteins represents an attractive target in the development of new drug therapies: In particular, modulation of the proteasome activity by specific inhibitors may represent a useful tool for the treatment of tumours. Here, we report synthesis and activity of a new series of oligopseudopeptide analogues bearing a vinyl ketone pharmacophoric unit at the C-terminal position. Some derivatives showed inhibition in the mu M range of the trypsin-like (T-L) active site of the proteasome
- …