Synthesis, Cytotoxicity Evaluation, and Computational Insights of Novel 1,4-Diazepane-Based Sigma Ligands.

Among several potential applications, sigma receptor ligands can be used as antipsychotics, antiamnesics, and against other neurodegenerative disorders as well as neuroprotective agents. We present herein a new series of diazepane-containing derivatives as σR ligands obtained by a conformational expansion approach of our previously synthesized piperidine-based compounds. The best results were reached by benzofurane , and quinoline , -substituted diazepane derivatives, which showed the highest σR affinity.

Effect of methylene blue photodynamic therapy on human neutrophil functional responses.

Photodynamic therapy (PDT) has become an emerging novel therapeutic approach for treating localized microbial infections, particularly those sustained by multidrug-resistant strains. Given the irreplaceable role played by professional phagocytes in limiting infections, such as polymorphonuclear neutrophils, any newly designed antimicrobial therapeutic approach must not interfere with their function. The present investigation presents a detailed analysis of the effect of PDT on the viability and several functional responses of human polymorphonuclear neutrophils loaded with methylene blue (MB), one of the more commonly used photosensitizers in antimicrobial PDT.

Discovery of new potent dual sigma receptor/GluN2b ligands with antioxidant property as neuroprotective agents.

Among several potential applications, sigma receptors (σRs) can be used as neuroprotective agents, antiamnesic, antipsychotics and against other neurodegenerative disorders. On the other hands, antagonists of the GluN2b-subunit-containing-N-methyl-D-aspartate (NMDA) receptors are of major interest for the same purpose, being this subunit expressed in specific areas of the central nervous system and responsible for the excitatory regulation of nerve cells. Under these premises, we have synthesized and biologically tested novel hybrid derivatives obtained from the combination of phenyloxadiazolone and dihydroquinolinone scaffolds with different amine moieties, peculiar of σ2R ligands.

Transcriptomics and Immunological Analyses Reveal a Pro-Angiogenic and Anti-Inflammatory Phenotype for Decidual Endothelial Cells.

Background: In pregnancy, excessive inflammation and break down of immunologic tolerance can contribute to miscarriage. Endothelial cells (ECs) are able to orchestrate the inflammatory processes by secreting pro-inflammatory mediators and bactericidal factors by modulating leakiness and leukocyte trafficking, via the expression of adhesion molecules and chemokines. The aim of this study was to analyse the differences in the phenotype between microvascular ECs isolated from decidua (DECs) and ECs isolated from human skin (ADMECs).

Chitosan Acetylation Degree Influences the Physical Properties of Polysaccharide Nanoparticles: Implication for the Innate Immune Cells Response.

The aim of the present contribution is twofold as it reports (i) on the role played by chitosan acetylation degree for the stability of nanoparticles (NPs) formed with hyaluronan and (ii) on the effect of the interaction of such NPs with immune cells. Chitosans with similar viscosity-average molecular weight, [Formula: see text], (i.e.

Complex Coacervates between a Lactose-Modified Chitosan and Hyaluronic Acid as Radical-Scavenging Drug Carriers.

Complex coacervation of two oppositely charged polysaccharides, namely a lactose-modified chitosan (CTL) and hyaluronan (HA), was investigated in this study. Coacervates of the two polysaccharides were prepared by drop-by-drop injection of HA into CTL. Transmittance and dynamic light scattering (DLS) measurements in combination with TEM analyses demonstrated the formation of spheroidal colloids in the nano-/microsize range showing good homogeneity.

New piperidine-based derivatives as sigma receptor ligands. Synthesis and pharmacological evaluation.

The sigma receptor (σR) family has been considered mysterious for a long time. In fact, the σ2R subtype has been cloned only recently, revealing its identity as TMEM97, a NPC1-binding protein involved in cholesterol biosynthesis and implicated in the pathogenesis of cancer and neurologic disorders. With the aim of developing new chemical entities gifted with σR affinity, herein we report the design and synthesis of new piperidine-based alkylacetamide derivatives with mixed affinity towards both σ1 and σ2R subtypes.

Butyrate-Loaded Chitosan/Hyaluronan Nanoparticles: A Suitable Tool for Sustained Inhibition of ROS Release by Activated Neutrophils.

Tissue damage caused by excessive amounts of neutrophil-derived reactive oxygen species (ROS) occurs in many inflammatory diseases. Butyrate is a short-chain fatty acid (SCFA) with known anti-inflammatory properties, able to modulate several neutrophil functions. Evidence is provided here that butyrate inhibits neutrophil ROS release in a dose and time-dependent fashion.

Intracellular shunting of O2(-) contributes to charge compensation and preservation of neutrophil respiratory burst in the absence of voltage-gated proton channel activity.

Proton efflux via voltage-gated proton channels (Hv1) is considered to mediate the charge compensation necessary to preserve NADPH oxidase activity during the respiratory burst. Using the Hv1 inhibitor Zn(2+), we found that the PMA-induced respiratory burst of human neutrophils is inhibited when assessed as extracellular production of O2(-) and H2O2, in accordance with literature studies, but, surprisingly, unaffected when measured as oxygen consumption or total (extracellular plus intracellular) H2O2 production. Furthermore, we show that inhibiting Hv1 with Zn(2+) results in an increased production of intracellular ROS.

Killing by neutrophil extracellular traps: fact or folklore?

Neutrophil extracellular traps (NETs) are DNA structures released by dying neutrophils and claimed to constitute a new microbicidal mechanism. Killing by NET-forming cells is ascribed to these structures because it is prevented by preincubation with DNase, which has been shown to dismantle NETs, before addition of the target microorganisms. Curiously, the possibility that the microorganisms ensnared in NETs are alive has not been considered.

Chloride movements in human neutrophils during phagocytosis: characterization and relationship to granule release.

Chloride ion efflux is an early event occurring after exposure of human neutrophils to several soluble agonists. Under these circumstances, a rapid and reversible fall in the high basal intracellular chloride (Cl-i) levels is observed. This event is thought to play a crucial role in the modulation of several critical neutrophil responses including activation and up-regulation of adhesion molecules, cell attachment and spreading, cytoplasmic alkalinization, and activation of the respiratory burst.

Common methodology is inadequate for studies on the microbicidal activity of neutrophils.

Microbicidal activity of neutrophils is usually measured by colony-counting techniques after cell lysis in distilled water. While studying the effect of the reduced nicotinamide adenine dinucleotide phosphate-oxidase inhibitor diphenyleneiodonium (DPI) on the staphylocidal activity of neutrophils, we obtained inconsistent results: various degrees of inhibition in some experiments and no effect in others. The lysis step, i.

A single-step, sensitive flow cytofluorometric assay for the simultaneous assessment of membrane-bound and ingested Candida albicans in phagocytosing neutrophils.

Background: Distinguishing ingested particles from those attached to the cell surface is an essential requirement when performing quantitative studies of phagocytosis. In the present report, we describe a simple, sensitive and reliable flow cytofluorometric method that achieves this goal in a Candida albicans-human neutrophils (PMN) system.

Methods: The assay is based on the observation that the vital dye trypan blue (TB), while quenching the green fluorescence of fluorescein-labeled C.

Evidence that elastase is the TNF-R75 shedding enzyme in resting human polymorphonuclear leukocytes.

We previously showed that a metalloprotease and a serine protease mediate shedding of the TNF-R75 (75-kDa tumor necrosis factor receptor) in neutrophils. Here we show that elastase is the TNF-R75 solubilizing serine protease. Release of the TNF-R75 by resting cells was almost totally inhibited by the serine protease inhibitor diisopropylfluorophosphate (DFP), by two synthetic, chemically unrelated, elastase-specific inhibitors and by alpha1-protease inhibitor.

Evidence that TNF-induced respiratory burst of adherent PMN is mediated by integrin alpha(L)beta(2).

Polymorphonuclear leukocytes (PMN) respond to tumor necrosis factor (TNF) with a respiratory burst (RB) only after adherence to surfaces coated with extracellular matrix proteins such as fibronectin and fibrinogen (permissive substrates) but not with others such as laminin or collagen (nonpermissive substrates). As PMN adherence to both types of surfaces is dependent on beta(2) integrins, we investigated the molecular basis of the different metabolic response to TNF. In particular, we evaluated the relative role of each beta(2) integrin (alpha(L)beta(2), alpha(M)beta(2), and alpha(X)beta(2)) in adherence and O(2)(-) production of PMN residing on fibronectin- and laminin-coated surfaces, which were considered as models of permissive and nonpermissive surfaces, respectively.