13 research outputs found

    Substance P induces gastric mucosal protection at supraspinal level via increasing the level of endomorphin-2 in rats.

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    The aim of the present study was to analyze the potential role of substance P (SP) in gastric mucosal defense and to clarify the receptors and mechanisms that may be involved in it. Gastric ulceration was induced by oral administration of acidified ethanol in male Wistar rats. Mucosal levels of calcitonin gene-related peptide (CGRP) and somatostatin were determined by radioimmunoassay. For analysis of gastric motor activity the rubber balloon method was used. We found that central (intracerebroventricular) injection of SP (9.3-74pmol) dose-dependently inhibited the formation of ethanol-induced ulcers, while intravenously injected SP (0.37-7.4nmol/kg) had no effect. The mucosal protective effect of SP was inhibited by pretreatment with neurokinin 1-, neurokinin 2-, neurokinin 3- and mu-opioid receptor antagonists, while delta- and kappa-opioid receptor antagonists had no effect. Endomorphin-2 antiserum also antagonized the SP-induced mucosal protection. In the gastroprotective dose range SP failed to influence the gastric motor activity. Inhibition of muscarinic cholinergic receptors, or the synthesis of nitric oxide or prostaglandins significantly reduced the effect of SP. In addition, centrally injected SP reversed the ethanol-induced reduction of gastric mucosal CGRP content. It can be concluded, that SP may induce gastric mucosal protection initiated centrally. Its protective effect is likely to be mediated by endomorphin-2, and vagal nerve may convey the centrally initiated protection to the periphery, where both prostaglandins, nitric oxide and CGRP are involved in mediating this effect

    An explainable model of host genetic interactions linked to COVID-19 severity

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    We employed a multifaceted computational strategy to identify the genetic factors contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing (WES) dataset of a cohort of 2000 Italian patients. We coupled a stratified k-fold screening, to rank variants more associated with severity, with the training of multiple supervised classifiers, to predict severity based on screened features. Feature importance analysis from tree-based models allowed us to identify 16 variants with the highest support which, together with age and gender covariates, were found to be most predictive of COVID-19 severity. When tested on a follow-up cohort, our ensemble of models predicted severity with high accuracy (ACC = 81.88%; AUCROC = 96%; MCC = 61.55%). Our model recapitulated a vast literature of emerging molecular mechanisms and genetic factors linked to COVID-19 response and extends previous landmark Genome-Wide Association Studies (GWAS). It revealed a network of interplaying genetic signatures converging on established immune system and inflammatory processes linked to viral infection response. It also identified additional processes cross-talking with immune pathways, such as GPCR signaling, which might offer additional opportunities for therapeutic intervention and patient stratification. Publicly available PheWAS datasets revealed that several variants were significantly associated with phenotypic traits such as "Respiratory or thoracic disease", supporting their link with COVID-19 severity outcome.A multifaceted computational strategy identifies 16 genetic variants contributing to increased risk of severe COVID-19 infection from a Whole Exome Sequencing dataset of a cohort of Italian patients

    Carriers of ADAMTS13 Rare Variants Are at High Risk of Life-Threatening COVID-19

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    Thrombosis of small and large vessels is reported as a key player in COVID-19 severity. However, host genetic determinants of this susceptibility are still unclear. Congenital Thrombotic Thrombocytopenic Purpura is a severe autosomal recessive disorder characterized by uncleaved ultra-large vWF and thrombotic microangiopathy, frequently triggered by infections. Carriers are reported to be asymptomatic. Exome analysis of about 3000 SARS-CoV-2 infected subjects of different severities, belonging to the GEN-COVID cohort, revealed the specific role of vWF cleaving enzyme ADAMTS13 (A disintegrin-like and metalloprotease with thrombospondin type 1 motif, 13). We report here that ultra-rare variants in a heterozygous state lead to a rare form of COVID-19 characterized by hyper-inflammation signs, which segregates in families as an autosomal dominant disorder conditioned by SARS-CoV-2 infection, sex, and age. This has clinical relevance due to the availability of drugs such as Caplacizumab, which inhibits vWF-platelet interaction, and Crizanlizumab, which, by inhibiting P-selectin binding to its ligands, prevents leukocyte recruitment and platelet aggregation at the site of vascular damage

    Gain- and Loss-of-Function CFTR Alleles Are Associated with COVID-19 Clinical Outcomes

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    Carriers of single pathogenic variants of the CFTR (cystic fibrosis transmembrane conductance regulator) gene have a higher risk of severe COVID-19 and 14-day death. The machine learning post-Mendelian model pinpointed CFTR as a bidirectional modulator of COVID-19 outcomes. Here, we demonstrate that the rare complex allele [G576V;R668C] is associated with a milder disease via a gain-of-function mechanism. Conversely, CFTR ultra-rare alleles with reduced function are associated with disease severity either alone (dominant disorder) or with another hypomorphic allele in the second chromosome (recessive disorder) with a global residual CFTR activity between 50 to 91%. Furthermore, we characterized novel CFTR complex alleles, including [A238V;F508del], [R74W;D1270N;V201M], [I1027T;F508del], [I506V;D1168G], and simple alleles, including R347C, F1052V, Y625N, I328V, K68E, A309D, A252T, G542*, V562I, R1066H, I506V, I807M, which lead to a reduced CFTR function and thus, to more severe COVID-19. In conclusion, CFTR genetic analysis is an important tool in identifying patients at risk of severe COVID-19

    The polymorphism L412F in TLR3 inhibits autophagy and is a marker of severe COVID-19 in males

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    The polymorphism L412F in TLR3 has been associated with several infectious diseases. However, the mechanism underlying this association is still unexplored. Here, we show that the L412F polymorphism in TLR3 is a marker of severity in COVID-19. This association increases in the sub-cohort of males. Impaired macroautophagy/autophagy and reduced TNF/TNFα production was demonstrated in HEK293 cells transfected with TLR3L412F-encoding plasmid and stimulated with specific agonist poly(I:C). A statistically significant reduced survival at 28 days was shown in L412F COVID-19 patients treated with the autophagy-inhibitor hydroxychloroquine (p = 0.038). An increased frequency of autoimmune disorders such as co-morbidity was found in L412F COVID-19 males with specific class II HLA haplotypes prone to autoantigen presentation. Our analyses indicate that L412F polymorphism makes males at risk of severe COVID-19 and provides a rationale for reinterpreting clinical trials considering autophagy pathways. Abbreviations: AP: autophagosome; AUC: area under the curve; BafA1: bafilomycin A1; COVID-19: coronavirus disease-2019; HCQ: hydroxychloroquine; RAP: rapamycin; ROC: receiver operating characteristic; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; TLR: toll like receptor; TNF/TNF-α: tumor necrosis factor

    Imidazoline versus alpha₂-adrenoceptors in the control of gastric motility in mice.

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    Several lines of evidence suggest that imidazoline receptors mediate various physiological processes. It is rather difficult, however, to distinguish the imidazoline receptor-mediated effects from the alpha₂-adrenoceptor-mediated ones due to the reasonable affinity of most imidazoline ligands for the alpha₂-adrenoceptors. In the present study the effects of different imidazoline ligands were tested on the electrical field stimulation (EFS)-induced gastric contractions in wild-type (WT), alpha₂A-, alpha₂B- and alpha₂C-adrenoceptor knockout (KO) mice in order to analyze, whether imidazoline I₁ and I₂ receptors take part in the regulation of gastric motor activity. Clonidine, moxonidine and rilmenidine inhibited the EFS-induced gastric contractions in a concentration dependent manner in WT, alpha₂B- and alpha₂C-adrenoceptor KO mice, whereas they had no or only weak effect in alpha₂A-adrenoceptor KO mice. Their effects in WT mice were inhibited by idazoxan and BRL 44408, but not by ARC 239, AGN 192403 and BU 224. The endogenous imidazoline receptor ligand agmatine failed to affect the EFS-induced contractions, while harmane (an other endogenous imidazoline receptor ligand) and 2-BFI (a selective imidazoline I2 receptor agonist) exerted a slight effect in both WT and alpha2A-adrenoceptor KO mice, but this was not reversible by idazoxan, AGN 192403 and BU 224. It can be concluded, that the inhibitory effect of the tested imidazoline compounds on cholinergic gastric contractions is mediated mainly by alpha₂A-adrenoceptors. Although at higher concentrations other receptors may also contribute to their effects, the lack of inhibition by AGN 192403 and BU 224 suggests that these are not imidazoline I₁ and I₂ receptors

    Venetoclax in Relapsed/Refractory Acute Myeloid Leukemia: Are Supporting Evidences Enough?

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    Despite the progress in the development of new therapeutic strategies, relapsed/refractory (R/R) acute myeloid leukemia (AML) still represents a high unmet medical need. Treatment options in this setting include enrollment into clinical trials, allogeneic stem cell transplantation and/or targeted therapy. Nevertheless, it is associated with poor outcomes. Thus, the development of new treatments, which could ameliorate the prognosis of these patients with a good safety profile are highly demanded. Recently, venetoclax (VEN) has been approved for naïve AML patients unfit for intensive chemotherapy. In this regard, regimens including VEN could represent a valuable treatment option even in those with R/R disease and several studies have been conducted to demonstrate its role in this clinical setting. This review aims to summarize the current evidence on the use of VEN regimens in the treatment of R/R AML

    Molecular Genetics of Niemann-Pick Type C Disease in Italy: An Update on 105 Patients and Description of 18 NPC1 Novel Variants

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    Niemann-Pick type C (NPC) disease is an autosomal recessive lysosomal storage disorder caused by mutations in NPC1 or NPC2 genes. In 2009, the molecular characterization of 44 NPC Italian patients has been published. Here, we present an update of the genetic findings in 105 Italian NPC patients belonging to 83 unrelated families (77 NPC1 and 6 NPC2). NPC1 and NPC2 genes were studied following an algorithm recently published. Eighty-four different NPC1 and five NPC2 alleles were identified. Only two NPC1 alleles remained non detected. Sixty-two percent of NPC1 alleles were due to missense variants. The most frequent NPC1 mutation was the p.F284Lfs*26 (5.8% of the alleles). All NPC2 mutations were found in the homozygous state, and all but one was severe. Among newly diagnosed patients, 18 novel NPC1 mutations were identified. The pathogenic nature of 7/9 missense alleles and 3/4 intronic variants was confirmed by filipin staining and NPC1 protein analysis or mRNA expression in patient's fibroblasts. Taken together, our previous published data and new results provide an overall picture of the molecular characteristics of NPC patients diagnosed so far in Italy

    Low dose aspirin and clinical outcomes in patients with SARS-CoV-2 pneumonia: a propensity score-matched cohort analysis from the National SIMI‑COVID‑19 Registry

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    Background: SARS- CoV-2 virus has had dramatic consequences worldwide being able to cause acute respiratory distress syndrome (ARDS), massive thrombosis and pulmonary embolism and, finally, patients' death. In COVID-19 infection, platelets have a procoagulant phenotype that can cause thrombosis in the pulmonary and systemic vascular network. Aspirin is a well-known anti-platelet drug widely used for the prevention of cardiovascular events and systematic reviews suggest a possible benefit of low-dose aspirin (LDA) use in the prevention and treatment of ARDS in patients with COVID-19 infection. However, several studies are available in the literature which do not support any benefits and no association with the patients' outcome. Therefore, currently available data are inconclusive. Materials and patients: Data from the nationwide cohort multicenter study of the Italian Society of Internal Medicine (SIMI) were analyzed. We conducted a propensity score-matched cohort analysis to investigate the impact of chronic assumption of LDA on mortality of adult COVID-19 patients admitted in Internal Medicine Units (IMU). Data from 3044 COVID-19 patients who referred to 41 Italian hospitals between February 3rd to May 8th 2020 were analyzed. A propensity score-matched analysis was conducted using the following variables: age, sex, hypertension, hyperlipidemia diabetes, atrial fibrillation, cerebrovascular disease, COPD, CKD and stratified upon LDA usage, excluding anticoagulant treatment. After matching, 380 patients were included in the final analysis (190 in LDA group and 190 in no-LDA group). Results: 66.2% were male, median age was 77 [70-83]. 34.8% of the population died during the hospitalization. Cardiovascular diseases were not significantly different between the groups. After comparison of LDA and no-LDA subgroups, we didn't record a significant difference in mortality rate (35.7% vs 33.7%) duration of hospital stay and ICU admission. In a logistic regression model, age (OR 1.05; 95% CI 1.01-1.09), FiO2 (OR 1.024; 95% CI 1.03-1.04) and days between symptoms onset and hospitalization (OR 0.93; 95% CI 0.87-0.99) were the only variables independently associated with death

    Corpus callosum abnormalities: neuroimaging, cytogenetics and clinical characterization of a very large multicenter Italian series

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    Corpus callosum abnormalities (CCA) have an estimated prevalence ranging from 0.3% up to 0.7% in patients undergoing brain imaging. CCA can be identified incidentally, or can be part of a developmental disease. We performed a retrospective study of 551 patients, identified non-syndromic (NS) CCA and syndromic (S) CCA, reviewing clinical features, neuroradiological aspects, genetic etiology, and chromosomal microarray (CMA) results. Syndromic CCA subjects were prevalent (60%) and they showed the most severe clinical features. Cortical malformations and cerebellar anomalies were 23% of cerebral malformation associated to CCA (plus), 23 and 14% respectively in syndromic forms. A clinical and/or genetic diagnosis was obtained in 37% of syndromic CCA including chromosomal rearrangements on high-resolution karyotype (18%), microdeletion/microduplication syndromes (31%) and monogenic diseases (51%). Non-syndromic CCA anomalies had mildest clinical features, although intellectual disability was present in 49% of cases and epilepsy in 13%. CMA diagnostic rate in our cohort of patients ranged from 11 to 23% (NS to S). A high percentage of patients (76% 422/551) remain without a diagnosis. Combined high resolution CMA studies and next-generation sequencing (NGS) strategies will increase the probability to identify new causative genes of CCA and to redefine genotype–phenotype correlation
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