High-resolution proteomic profiling of spider venom: expanding the toxin diversity of Phoneutria nigriventer venom.

Here we present a proteomic characterization of Phoneutria nigriventer venom. A shotgun proteomic approach allowed the identification, for the first time, of O-glycosyl hydrolases (chitinases) in P. nigriventer venom. The electrophoretic profiles under nonreducing and reducing conditions, and protein identification by mass spectrometry, indicated the presence of oligomeric toxin structures in the venom. Complementary proteomic approaches allowed for a qualitative and semi-quantitative profiling of P. nigriventer venom complexity, expanding its known venom proteome diversity.

Suture-Mediated Patent Foramen Ovale Closure Using the NobleStitch EL: Results from a Hospital-Based HTA.

(1) Background: Patent foramen ovale (PFO) is a congenital abnormality present in up to 25% of the general population, and it is a relevant cause of cryptogenic stroke. We applied the hospital-based HTA model (AdHopHTA) to conduct a multidimensional assessment of NobleStitch EL, an innovative suture-mediated PFO closure device. We compared it to Amplatzer PFO Occluder (APO) to provide evidence to inform technologies' governance in hospital settings. (2) Methods: For each AdHopHTA dimension we: systematically retrieved available evidence from the literature applying the PRISMA guidelines and then analyzed original clinical and cost data of a NobleStitch EL device at San Raffaele research hospital in Milan (Italy). The economic dimension was analyzed through activity-based costing and a cost analysis. We conducted semi-structured interviews with selected healthcare professionals to explore the organizational, legal, social, and ethical impact. (3) Results: A single study was included for the NobleStitch EL, with 10 for APO. Both literature data and original data showed comparable safety. Efficacy data analysis found that the PFO closure was at 89% for NobleStitch EL vs. 89-97% for APO. APO has a better impact on the budget and minor process costs. Consulted experts reported that the organizational impact of NobleStitch EL in the short and the long run as null, albeit a better impact under the social and the ethical aspects. (4) Conclusion: We suggest that there is inadequate evidence to conclude the relative efficacy of NobleStitch EL as compared to APO. Nevertheless, this report shows a good safety profile and higher costs for NobleStitch EL, with no organizational or legal impact. Further studies in selected population are recommended.

A virtual reality home-based training for the management of stress and anxiety among healthcare workers during the COVID-19 pandemic: study protocol for a randomized controlled trial.

BACKGROUND: Healthcare workers represent one of the most affected categories by the adverse effects of the COVID-19 pandemic on mental health. Excessive stress and anxiety are critical factors that could compromise work performance. Besides, high levels of stress and anxiety may have long-term physical and psychological consequences. Recent studies investigated virtual reality to reduce stress and anxiety among healthcare workers during the COVID-19 pandemic. However, the proposed virtual reality interventions have important limitations related to their location (i.e., research lab and hospitals) and content (i.e., virtual experiences only for relaxation). Within this context, this randomized controlled trial aims to investigate the efficacy and acceptability of a brief home-based virtual reality training for managing stress and anxiety during the COVID-19 crisis in a sample of Italian healthcare workers. METHODS: The study is a randomized controlled trial. It includes two groups of 30 individuals recruited from healthcare workers: (1) the experimental group and (2) the control group. Participants in the experimental group will receive a training consisting of three home sessions performed in a week. In each session, participants will try through an immersive virtual reality standalone system (i.e., Oculus Quest 2) a virtual psychoeducation experience on stress and anxiety (i.e., MIND-VR). Subsequently, they will try the virtual relaxation content (i.e., The Secret Garden). The control group will receive no training and will be reassessed one week and one month after the initial evaluation. DISCUSSION: If the proposed brief home-based virtual reality training will result helpful and easy to use, it could become an empirically assessed viable option for protecting healthcare workers' mental health both during the COVID-19 pandemic and once it will be over. Furthermore, the intervention might be easily adapted for other categories of people who need support in managing stress and anxiety. TRIAL REGISTRATION: ClinicalTrials.gov NCT04611399 .

Glycine stimulates the release of labeled acetylcholine but not dopamine nor glutamate from superfused rat striatal tissue.

Glycine is known as an inhibitory neurotransmitter in the spinal cord and forebrain but its precise role in the forebrain is largely overlooked. This investigation evaluated whether glycine alters acetylcholine, glutamate or dopamine release from striatal tissue using an in vitro approach. We observed that while glycine induced a robust (3)H-acetylcholine release ((3)H-ACh) from superfused striatal tissue, it failed at releasing (3)H-glutamate or (3)H-dopamine. Glycine stimulated (3)H-ACh release in a dose- and calcium-dependent manner (EC(50)=69 microM). Tetrodotoxin (1 microM) inhibited about 75% of the release demonstrating a predominant dendritic and cell body location of glycine receptors. The prototypical glycine receptor antagonist strychnine at 10 microM completely abolished (3)H-ACh release. To further characterize the role of striatal glycine receptors in (3)H-ACh release we examined glycine effects after in vivo treatment with Haloperidol-decanoate (HD). Treatment for 30 days or more with HD decreased maximal glycine-stimulated release of (3)H-ACh suggesting a non-competitive inhibition. After 30 days of washout release parameters did not return to vehicle-treated levels. The glutamate agonist NMDA also stimulated acetylcholine release but showed slightly different behavior in HD-treated striatal tissue. These effects could be attributed to changes in chloride transporters expressed in the giant striatal cholinergic cell as well as glycine receptor subunit composition and finally, GABA/glycine co-release in this tissue.

Phoneutria nigriventer spider toxin Tx2-6 induces priapism in mice even after cavernosal denervation.

The Phoneutria nigriventer spider toxin Tx2-6 causes priapism in humans and mice. This toxin produces a delay in Sodium channel inactivation, generalized vascular congestion and death by respiratory failure. NO-Synthase inhibitors seem to abolish toxin-induced priapism. The understanding of the ultimate molecular mechanism involved in toxin-induced priapism may shed light on aspects of erectile function/dysfunction. This study investigates if cavernosal denervation can abolish the toxin-induced priapism. Surgical cavernosal nerve excision/denervation was performed in mice and confirmed by infertility, histological assessment of fibrosis and immunohistochemical staining for synaptophysin. Denervated mice showed intense fibrosis of the cavernosal tissue as well as absence of synaptophysin IHC staining; surprisingly mice showed toxin-induced priapism when tested 15, 30 or 60 days after denervation. While sham-operated mice presented full priapism, denervated animals showed only partial priapism possibly due to the fibrosis. These results reveal that erection caused by Tx2-6 toxin may not depend on cavernosal nerves integrity. The effect of this toxin on sodium channels seem not directly involved in priapism as many toxins have identical effects but do not induce priapism. Discussion approaches the many different potential sites of intervention listed in the signaling cascades of NO/cGMP, RhoA/Rho-Kinase, as well as the emerging new gasotransmitter H2S. The pharmacological inhibition of Rho-kinase and toxin Tx2-6 have similar effects in vivo.

1-[(2,3-Dihydro-1-benzofuran-2-yl) methyl]piperazines as novel anti-inflammatory compounds: Synthesis and evaluation on H3 R/H4 R.

The histamine receptors (HRs) are members of G-protein-coupled receptor superfamily and traditional targets of huge therapeutic interests. Recently, H3 R and H4 R have been explored as targets for drug discovery, including in the search for dual-acting H3 R/H4 R ligands. The H4 R, the most recent histamine receptor, is a promising target for novel anti-inflammatory agents in several conditions such as asthma and other chronic inflammatory diseases. Due to similarity with previously reported ligands of HRs, a set of 1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazines were synthesized and evaluated in competitive binding assays as H3 R/H4 R ligands herein. The results showed the compounds presented affinity (Ki ) for H3 R/H4 R in micromolar range, and they are more selective to H3 R. All the compounds showed no important cytotoxicity to mammalian cells. The phenyl-substituted compound LINS01005 has shown the higher affinity of the set for H4 R, but no considerable selectivity toward this receptor over H3 R. LINS01005 showed interesting anti-inflammatory activity in murine asthma model, reducing the eosinophil counts in bronchoalveolar lavage fluid, as well as the COX-2 expression. The presented compounds are valuable prototypes for further improvements to achieve better anti-inflammatory agents.

Drug-induced suppression of ACTH secretion does not promote anti-depressive or anxiolytic effects.

Mammals respond to a real or perceived stress in an integrated physiological and psychological fashion. Psychiatric disorders like major depression and anxiety have been associated to stressful events. In a previous study we demonstrated that the stress-induced ACTH secretion can be robustly inhibited by the concurrent use of CRF1 (CP154,526 - Pfizer) and V1B (SSR149415 - Sanofi-Aventis) non-peptide antagonists. A proof of mechanism was offered by substituting CP154,526 by SSR125543 and obtaining the same results on three stress models: forced swimming, ether vapor inhalation and restraint. SSR125543 effectively blocked only restraint stress-induced ACTH secretion. We then challenged the hypothesis that the concurrent use of both antagonists would have a potent effect on behavioral models of anxiety and depression. Decreasing doses (30-0.1 mg/kg s.c.) of both drugs were tested in three behavioral models: Porsolt forced swimming test, elevated plus maze and social interaction. Results showed that these drugs had no effect on anxiety models (plus maze and social interaction) but significantly reduced immobility time in the forced swimming test, suggesting anti-depressive action in a dose-range from 1 to 30 mg/kg, not different from the reported in the literature referring to one drug or the other. This negates the proposed hypothesis of summation/potentiation of effects as observed in stress-induced ACTH secretion. These results point toward the involvement of extra-hypothalamic sites for the anti-depressive effects. Recent Phase II clinical research on anti-depressive effects of these drugs has failed rising strong criticisms against the predictive value of behavioral tests currently employed.

Phoneutria nigriventer spider toxin Tx2-6 induces priapism in mice even after cavernosal denervation

The Phoneutria nigriventer spider toxin Tx2-6 causes priapism in humans and mice. This toxin produces a delay in Sodium channel inactivation, generalized vascular congestion and death by respiratory failure. NO-Synthase inhibitors seem to abolish toxin-induced priapism. The understanding of the ultimate molecular mechanism involved in toxin-induced priapism may shed light on aspects of erectile function/dysfunction. This study investigates if cavernosal denervation can abolish the toxin-induced priapism. Surgical cavernosal nerve excision/denervation was performed in mice and confirmed by infertility, histological assessment of fibrosis and immunohistochemical staining for synaptophysin. Denervated mice showed intense fibrosis of the cavernosal tissue as well as absence of synaptophysin IHC staining; surprisingly mice showed toxin induced priapism when tested 15, 30 or 60 days after denervation. While sham-operated mice presented full priapism, denervated animals showed only partial priapism possibly due to the fibrosis. These results reveal that erection caused by Tx2-6 toxin may not depend on cavernosal nerves integrity. The effect of this toxin on sodium channels seem not directly involved in priapism as many toxins have identical effects but do not induce priapism. Discussion approaches the many different potential sites of intervention listed in the signaling cascades of NO/cCMP, RhoA/Rho-Kinase, as well as the emerging new gasotransmitter H2S. The pharmacological inhibition of Rho-kinase and toxin Tx2-6 have similar effects in vivo.

1-[(2,3-Dihydro-1-benzofuran-2-yl) methyl]piperazines as novel anti-inflammatory compounds: synthesis and evaluation on H3R/H4R

The histamine receptors (HRs) are members of G-protein-coupled receptor superfamily and traditional targets of huge therapeutic interests. Recently, H3R and H4R have been explored as targets for drug discovery, including in the search for dual-acting H3R/H4R ligands. The H4R, the most recent histamine receptor, is a promising target for novel anti-inflammatory agents in several conditions such as asthma and other chronic inflammatory diseases. Due to similarity with previously reported ligands of HRs, a set of 1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazines were synthesized and evaluated in competitive binding assays as H3R/H4R ligands herein. The results showed the compounds presented affinity (K-i) for H3R/H4R in micromolar range, and they are more selective to H3R. All the compounds showed no important cytotoxicity to mammalian cells. The phenyl-substituted compound LINS01005 has shown the higher affinity of the set for H4R, but no considerable selectivity toward this receptor over H3R. LINS01005 showed interesting anti-inflammatory activity in murine asthma model, reducing the eosinophil counts in bronchoalveolar lavage fluid, as well as the COX-2 expression. The presented compounds are valuable prototypes for further improvements to achieve better anti-inflammatory agents.

Control of Stress-Induced ACTH Secretion by Vasopressin and CRH: Additional Evidence

Vasopressin and CRH have complementary roles in the secretion of ACTH following different stress modalities. The concomitant use of V-1b and CRF1 receptor antagonists completely inhibits ACTH secretion in response to different stress modalities. The combination of the CRF1 antagonist SSR125543 with the V-1b antagonist SSR149415 effectively suppressed plasma ACTH 1.30 h after injection in rats stressed by ether vapor inhalation for 1 min, restraint stress for 1 h or forced swimming for 5 min. The duration of the effect was also studied. The CRF1 antagonist effectively suppressed ACTH secretion in restraint stress, while the V-1b antagonist was effective against ether inhalation. Both antagonists were necessary to block the forced swimming stress response. SSR125543 induced a prolonged effect and can be used in a model of prolonged HPA axis blockade. (C) 2016 S. Karger AG, Basel

High-resolution proteomic profiling of spider venom: expanding the toxin diversity of Phoneutria nigriventer venom

Here we present a proteomic characterization of Phoneutria nigriventer venom. A shotgun proteomic approach allowed the identification, for the first time, of O-glycosyl hydrolases (chitinases) in P. nigriventer venom. The electrophoretic profiles under nonreducing and reducing conditions, and protein identification by mass spectrometry, indicated the presence of oligomeric toxin structures in the venom. Complementary proteomic approaches allowed for a qualitative and semi-quantitative profiling of P. nigriventer venom complexity, expanding its known venom proteome diversity