TRPV1 channels are critical brain inflammation detectors and neuropathic pain biomarkers in mice.

The capsaicin receptor TRPV1 has been widely characterized in the sensory system as a key component of pain and inflammation. A large amount of evidence shows that TRPV1 is also functional in the brain although its role is still debated. Here we report that TRPV1 is highly expressed in microglial cells rather than neurons of the anterior cingulate cortex and other brain areas.

Extracellular proteasome-osteopontin circuit regulates cell migration with implications in multiple sclerosis.

Osteopontin is a pleiotropic cytokine that is involved in several diseases including multiple sclerosis. Secreted osteopontin is cleaved by few known proteases, modulating its pro-inflammatory activities. Here we show by in vitro experiments that secreted osteopontin can be processed by extracellular proteasomes, thereby producing fragments with novel chemotactic activity.

Sphingosine-1-Phosphate (S1P) Impacts Presynaptic Functions by Regulating Synapsin I Localization in the Presynaptic Compartment.

Unlabelled: Growing evidence indicates that sphingosine-1-P (S1P) upregulates glutamate secretion in hippocampal neurons. However, the molecular mechanisms through which S1P enhances excitatory activity remain largely undefined. The aim of this study was to identify presynaptic targets of S1P action controlling exocytosis.

Bone marrow mesenchymal stromal cells drive protective M2 microglia polarization after brain trauma.

Microglia/macrophages (M) are major contributors to postinjury inflammation, but they may also promote brain repair in response to specific environmental signals that drive classic (M1) or alternative (M2) polarization. We investigated the activation and functional changes of M in mice with traumatic brain injuries and receiving intracerebroventricular human bone marrow mesenchymal stromal cells (MSCs) or saline infusion. MSCs upregulated Ym1 and Arginase-1 mRNA (p < 0.

Myeloid microvesicles are a marker and therapeutic target for neuroinflammation.

Objective: Microvesicles (MVs) have been indicated as important mediators of intercellular communication and are emerging as new biomarkers of tissue damage. Our previous data indicate that reactive microglia/macrophages release MVs in vitro. The aim of the study was to evaluate whether MVs are released by microglia/macrophages in vivo and whether their number varies in brain inflammatory conditions, such as multiple sclerosis (MS).

Kainate induces mobilization of synaptic vesicles at the growth cone through the activation of protein kinase A.

Activation of protein kinase A (PKA) pathway at presynaptic terminals plays a crucial role in the supply of synaptic vesicles (SVs) from the reserve pool, affecting the steady-state level of activity and the reconstitution of the readily releasable pool after intense stimulation. However, the identity of the stimuli activating this pathway is undefined. Using fluorescence resonance energy transfer and molecular genetic, we show that kainate, through the activation of presynaptic kainate receptors, induces PKA activation and enhances synapsin I phosphorylation at PKA-specific residues.

Microvesicles released from microglia stimulate synaptic activity via enhanced sphingolipid metabolism.

Microvesicles (MVs) released into the brain microenvironment are emerging as a novel way of cell-to-cell communication. We have recently shown that microglia, the immune cells of the brain, shed MVs upon activation but their possible role in microglia-to-neuron communication has never been explored. To investigate whether MVs affect neurotransmission, we analysed spontaneous release of glutamate in neurons exposed to MVs and found a dose-dependent increase in miniature excitatory postsynaptic current (mEPSC) frequency without changes in mEPSC amplitude.

TI-VAMP/VAMP7 is the SNARE of secretory lysosomes contributing to ATP secretion from astrocytes.

Background Information: ATP is the main transmitter stored and released from astrocytes under physiological and pathological conditions. Morphological and functional evidence suggest that besides secretory granules, secretory lysosomes release ATP. However, the molecular mechanisms involved in astrocytic lysosome fusion remain still unknown.

Synthesis of novel chiral Δ2-isoxazoline derivatives related to ABT-418 and estimation of their affinity at neuronal nicotinic acetylcholine receptor subtypes.

The enantiopure diastereomeric Δ2-isoxazoline derivatives (2S,5'R)-5a-10a and (2S,5'S)-5b, (2S,5'S)-9b, (2S,5'S)-11b, which are structural analogues of both ABT-418 2 and oxyimino ethers (S)-3 and (Z)-(S)-4, were synthesized through cycloaddition reactions involving nitrile oxides as 1,3-dipoles and (S)-N-Boc-2-vinylpyrrolidine-13 as the dipolarophile. The absolute configuration was unequivocally assigned to target compounds by means of an X-ray analysis. The derivatives under study were assayed at neuronal acetylcholine nicotinic receptors (nAChRs), where they showed a meaningful reduction in affinity at the heteromeric α4β2 subtype when compared to the reference molecules.

Synthesis, binding, and modeling studies of new cytisine derivatives, as ligands for neuronal nicotinic acetylcholine receptor subtypes.

The availability of drug affecting neuronal nicotinic acetylcholine receptors (nAChRs) may have important therapeutic potential for the treatment of several CNS pathologies. Pursuing our efforts on the systematic structural modification of cytisine and N-arylalkyl and N-aroylalkyl cytisines were synthesized and tested for the displacement of [(3)H]-epibatidine and [(125)I]-alpha-bungarotoxin from the most widespread brain nAChRs subtypes alpha(4)beta(2) and alpha(7), respectively. While the affinity for alpha(7) subtype was rather poor (K(i) from 0.

Acid sphingomyelinase activity triggers microparticle release from glial cells.

We have earlier shown that microglia, the immune cells of the CNS, release microparticles from cell plasma membrane after ATP stimulation. These vesicles contain and release IL-1beta, a crucial cytokine in CNS inflammatory events. In this study, we show that microparticles are also released by astrocytes and we get insights into the mechanism of their shedding.

New analogues of epiboxidine incorporating the 4,5-dihydroisoxazole nucleus: synthesis, binding affinity at neuronal nicotinic acetylcholine receptors, and molecular modeling investigations.

A group of novel 4,5-dihydro-3-methylisoxazolyl derivatives, structurally related to epiboxidine (=(1R,4S,6S)-6-(3-methylisoxazol-5-yl)-7-azabicyclo[2.2.1]heptane), was prepared via 1,3-dipolar cycloaddition of acetonitrile oxide to different olefins.

Regulation of neuronal nicotinic receptor traffic and expression.

Neuronal nicotinic acetylcholine receptors (nAChRs) are a family of cation channels widely distributed in the brain, whose subunit composition and biophysical properties vary depending on the subtype and the area of the brain in which they are found. Brain nAChRs are also the target of nicotine, the most widespread drug of abuse. Chronic nicotine exposure differentially affects the number, subunit composition, stoichiometry and functional state of some nAChR subtypes, leaving others substantially unaffected.

Synthesis and alpha4beta2 nicotinic affinity of unichiral 5-(2-pyrrolidinyl)oxazolidinones and 2-(2-pyrrolidinyl)benzodioxanes.

The RS and SR enantiomers of 2-oxazolidinone and 1,4-benzodioxane bearing a 2-pyrrolidinyl substituent at the 5- and 2-position, respectively, were synthesized as candidate nicotinoids. One of the two benzodioxane stereoisomers reasonably fits the pharmacophore elements of (S)-nicotine and binds at alpha4beta2 nicotinic acetylcholine receptor with submicromolar affinity. Interestingly, both the synthesized pyrrolidinylbenzodioxanes exhibit analogous affinity at alpha(2) adrenergic receptor resembling the behaviour of some known alpha(2)-AR ligands recently proved to possess neuronal nicotinic affinity.

Selective nicotinic acetylcholine receptor subunit deficits identified in Alzheimer's disease, Parkinson's disease and dementia with Lewy bodies by immunoprecipitation.

Antibodies raised against human alpha2-6 and beta2-4 nicotinic receptor subunits were utilized to fractionate (3)H-epibatidine binding in human temporal cortex and striatum. The predominant receptor subtypes in both regions contained alpha4 and beta2 subunits. In normal cortex, 10% of binding was also associated with alpha2 subunits, whereas in the striatum, contributions by alpha6 (17%) and beta3 (23%) were observed.

Long-term exposure to the new nicotinic antagonist 1,2-bisN-cytisinylethane upregulates nicotinic receptor subtypes of SH-SY5Y human neuroblastoma cells.

Nicotinic drug treatment can affect the expression of neuronal nicotinic acetylcholine receptors (nAChR) both in vivo and in vitro through molecular mechanisms not fully understood. The present study investigated the effect of the novel cytisine dimer 1,2-bisN-cytisinylethane (CC4) on nAChR natively expressed by SH-SY5Y neuroblastoma cells in culture. CC4 lacked the agonist properties of cytisine and was a potent antagonist (IC50=220 nM) on nAChRs.

Expression of nigrostriatal alpha 6-containing nicotinic acetylcholine receptors is selectively reduced, but not eliminated, by beta 3 subunit gene deletion.

mRNAs for the neuronal nicotinic acetylcholine receptor (nAChR) alpha6 and beta3 subunits are abundantly expressed and colocalized in dopaminergic cells of the substantia nigra and ventral tegmental area. Studies using subunit-null mutant mice have shown that alpha6- or beta3-dependent nAChRs bind alpha-conotoxin MII (alpha-CtxMII) with high affinity and modulate striatal dopamine release. This study explores the effects of beta3 subunit-null mutation on striatal and midbrain nAChR expression, composition, and pharmacology.

Nicotinic acetylcholine receptor subtypes expression during rat retina development and their regulation by visual experience.

By acting through retinal nicotinic acetylcholine receptors (nAChRs), acetylcholine plays an important role in the development of both the retina and central visual pathways. Ligand binding and immunoprecipitation studies with subunit-specific antibodies showed that the expression of alphaBungarotoxin (alphaBgtx) and high-affinity epibatidine (Epi) receptors is regulated developmentally and increases until postnatal day 21 (P21). The increase in Epi receptors is caused by a selective increase in the subtypes containing the alpha2, alpha4, alpha6, beta2, and beta3 subunits.

Molecular determinants of intrinsic resistance to doxorubicin in human cancer cell lines.

Intrinsic or acquired drug resistance poses a major challenge to the success of chemotherapy in the clinical management of human cancers. While acquired multidrug resistance (MDR), whereby cells become refractory to multiple drugs, has been extensively investigated, the mechanistic basis for intrinsic resistance remains elusive, so that this condition is largely unmanageable in the clinical setting. To address this issue, we have assessed the effects of the anticancer agent doxorubicin (DX) on a panel of human tumor cell lines originally derived from untreated patients and tried to establish a correlation between cell response and a number of parameters, including drug accumulation and/or drug efflux; differences in expression and/or subcellular distribution of proteins involved in the apoptotic process (e.