Cortical nNOS neurons co-express the NK1 receptor and are depolarized by Substance P in multiple mammalian species

We have previously demonstrated that Type I neuronal nitric oxide synthase (nNOS)-expressing neurons are sleep-active in the cortex of mice, rats, and hamsters. These neurons are known to be GABAergic, to express Neuropeptide Y (NPY) and, in rats, to co-express the Substance P (SP) receptor NK1, suggesting a possible role for SP in sleep/wake regulation. To evaluate the degree of co-expression of nNOS and NK1 in the cortex among mammals, we used double immunofluorescence for nNOS and NK1 and determined the anatomical distribution in mouse, rat, and squirrel monkey cortex. Type I nNOS neurons co-expressed NK1 in all three species although the anatomical distribution within the cortex was species-specific. We then performed in vitro patch clamp recordings in cortical neurons in mouse and rat slices using the SP conjugate tetramethylrhodamine-SP (TMR-SP) to identify NK1-expressing cells and evaluated the effects of SP on these neurons. Bath application of SP (0.03–1 μM) resulted in a sustained increase in firing rate of these neurons; depolarization persisted in the presence of tetrodotoxin. These results suggest a conserved role for SP in the regulation of cortical sleep-active neurons in mammals

A blood atlas of COVID-19 defines hallmarks of disease severity and specificity.

Treatment of severe COVID-19 is currently limited by clinical heterogeneity and incomplete description of specific immune biomarkers. We present here a comprehensive multi-omic blood atlas for patients with varying COVID-19 severity in an integrated comparison with influenza and sepsis patients versus healthy volunteers. We identify immune signatures and correlates of host response. Hallmarks of disease severity involved cells, their inflammatory mediators and networks, including progenitor cells and specific myeloid and lymphocyte subsets, features of the immune repertoire, acute phase response, metabolism, and coagulation. Persisting immune activation involving AP-1/p38MAPK was a specific feature of COVID-19. The plasma proteome enabled sub-phenotyping into patient clusters, predictive of severity and outcome. Systems-based integrative analyses including tensor and matrix decomposition of all modalities revealed feature groupings linked with severity and specificity compared to influenza and sepsis. Our approach and blood atlas will support future drug development, clinical trial design, and personalized medicine approaches for COVID-19

α6β2* and α4β2* Nicotinic Receptors Both Regulate Dopamine Signaling with Increased Nigrostriatal Damage: Relevance to Parkinson's Disease

Nicotinic receptors (nAChRs) are important modulators of dopaminergic transmission in striatum, a region critical to Parkinson's disease. The nAChRs mainly involved are the α6β2* and α4β2* subtypes. Lesion studies show that the α6β2* receptor is decreased to a much greater extent with nigrostriatal damage than the α4β2* subtype raising the question whether this latter nAChR population is more important with increased nigrostriatal damage. To address this, we investigated the effect of varying nigrostriatal damage on α6β2* and α4β2* receptor-modulated dopamine signaling using cyclic voltammetry. This approach offers the advantage that changes in dopamine release can be observed under different neuronal firing conditions. Total single-pulse-evoked dopamine release decreased in direct proportion to declines in the dopamine transporter and dopamine uptake. We next used α-conotoxinMII and mecamylamine to understand the role of the α4β2* and α6β2* subtypes in release. Single-pulse–stimulated α6β2* and α4β2* receptor dopamine release decreased to a similar extent with increasing nigrostriatal damage, indicating that both subtypes contribute to the control of dopaminergic transmission with lesioning. Total burst-stimulated dopamine release also decreased proportionately with nigrostriatal damage. However, the role of the α4β2* and α6β2* nAChRs varied with different degrees of lesioning, suggesting that the two subtypes play a unique function with burst firing, with a somewhat more prominent and possibly more selective role for the α6β2* subtype. These data have important therapeutic implications because they suggest that drugs directed to both α4β2* and α6β2* nAChRs may be useful in the treatment of neurological disorders such as Parkinson's disease

Comprehensive virtual screening of 4.8 k flavonoids reveals novel insights into allosteric inhibition of SARS-CoV-2 M^PRO

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado.SARS-CoV-2 main protease is a common target for inhibition assays due to its high conservation among coronaviruses. Since flavonoids show antiviral activity, several in silico works have proposed them as potential SARS-CoV-2 main protease inhibitors. Nonetheless, there is reason to doubt certain results given the lack of consideration for flavonoid promiscuity or main protease plasticity, usage of short library sizes, absence of control molecules and/or the limitation of the methodology to a single target site. Here, we report a virtual screening study where dorsilurin E, euchrenone a11, sanggenol O and CHEMBL2171598 are proposed to inhibit main protease through different pathways. Remarkably, novel structural mechanisms were observed after sanggenol O and CHEMBL2171598 bound to experimentally proven allosteric sites. The former drastically affected the active site, while the latter triggered a hinge movement which has been previously reported for an inactive SARS-CoV main protease mutant. The use of a curated database of 4.8 k flavonoids, combining two well-known docking software (AutoDock Vina and AutoDock4.2), molecular dynamics and MMPBSA, guaranteed an adequate analysis and robust interpretation. These criteria can be considered for future screening campaigns against SARS-CoV-2 main protease.Consejo Nacional de Ciencia, Tecnología e Innovación TecnológicaRevisión por pare