The present work analyses in detail the published data on ChAdOx1 nCoV-19 vaccine and provides arguments for the involvement of anti-vector immunity and of SARS-CoV-2 variants on the efficacy of ChAdOx1 nCoV-19 vaccine. First, it is suggested that anti-vector immunity takes place as the regimen of homologous vaccination with ChAdOx1 nCoV-19 vaccine is applied and interferes with efficacy of the vaccine when the interval between prime and boost doses is less than three months. Second, longitudinal studies suggest that ChAdOx1 nCoV-19 vaccine provides sub-optimal efficacy against UK variant of SARS-CoV-2, which appears to have an increased transmissibility over the ancestral SARS-CoV-2 among vaccinated people. At the moment, ChAdOx1 nCoV-19 vaccine is able to reduce the severity of symptoms and transmissibility; however, if the vaccinated individuals do not maintain everyday preventive actions, they could turn into potential spreaders, thus accelerating the process of generation of new viral variants due to the selective pressure of immune response. Prediction and possible consequences of the SARS-CoV-2 evolution and repeated anti-SARS-CoV-2 vaccinations are discussed. Since the impact of emerging SARS-CoV-2 variants suggests that vaccines are unlikely to be effective in quickly solving the pandemic crisis, it is highlighted the need to keep searching for new and more efficacious pharmacotherapy for COVID-19, such as those targeting ACE2 and ADAM17 zinc-metalloprotease activities.
Background and Purpose Ca2+ influx via TRPV4 triggers Ca2+ release from the IP3-sensitive internal store to generate repetitive oscillations. While mitochondria are acknowledged regulators of IP3-mediated Ca2+ release, how TRPV4-mediated Ca2+ signals are regulated by mitochondria is unknown. We show that depolarised mitochondria switch TRPV4 signalling from relying on Ca2+-induced Ca2+ release at IP3 receptors, to being independent of Ca2+ influx and instead mediated by ATP release via pannexins. Experimental Approach TRPV4 evoked Ca2+ signals were individually examined in hundreds of cells in the endothelium of rat mesenteric resistance arteries using the indicator Cal520. Key ResultsTRPV4 activation with GSK1016790A(GSK) generated repetitive Ca2+ oscillations that required Ca2+ influx. However, when the mitochondrial membrane potential was depolarised, by the uncoupler CCCP or complex I inhibitor rotenone, TRPV4 activation generated large propagating, multicellular, Ca2+ waves in the absence of external Ca2+. The ATP synthase inhibitor oligomycin did not potentiate TRPV4 mediated Ca2+ signals. GSK-evoked Ca2+ waves, when mitochondria were depolarised, were blocked by the TRPV4 channel blocker HC067047, the SERCA inhibitor cyclopiazonic acid, the phospholipase C (PLC) blocker U73122 and the inositol triphosphate receptor (IP3 R) blocker caffeine. The Ca2+ waves were also inhibited by the extracellular ATP blockers suramin and apyrase and the pannexin blocker probenecid. Conclusion and Implications These results highlight a previously unknown role of mitochondria in shaping TRPV4 mediated Ca2+ signalling by facilitating ATP release. When mitochondria are depolarised, TRPV4-mediated release of ATP via pannexin channels activates plasma membrane purinergic receptors to trigger IP3 evoked Ca2+ release.
Since the start of the novel coronavirus SARS-Cov-2 pandemic, a disease that has become one of the world’s greatest global health challenges, the role of the immune system has been at the forefront of scientific studies. The pathophysiology of COVID-19 is complex, which is evident by those at higher risk for poor outcome. Multiple systems contribute to thrombosis and inflammation seen in COVID-19 patients, including neutrophil dysfunction, platelet activation, endothelial cell activation. Understanding how the immune system functions in different patient cohorts (particularly given recent emerging events with the Oxford/AstraZeneca vaccine) is vital to understanding the pathophysiology of this devastating disease and for subsequent development of novel therapeutic targets and expedite possible drug repurposing strategies that could benefit society on a global scale.
Pyroptosis, is a specialized form of inflammatory cell death which aids the defensive response against invading pathogens. Its tight regulation is lost during infection by the severe acute respiratory coronavirus 2 (SARS-CoV-2) and thus uncontrolled pyroptosis disrupts the immune system and the integrity of organs defining the critical conditions in patients with high viral load. Molecular pathways engaged downstream to the formation and stabilization of the inflammasome -required to execute the process- have been uncovered and drugs are available for their regulation. On the contrary, pharmacological inferring of the upstream events -which are critical to sense and interpret the initial damage by the pathogen- is far from being elucidated. This limits our capacity to identify early markers and targets to ameliorate SARS-CoV-2 linked pyroptosis. Here we aim to raise attention on mitochondria and pathways leading to its dysfunction with the goal to inform early steps of inflammasome and devise tools to interpret and counteract diseases by the SARS-CoV-2.
Cancer cachexia is one of the most common causes of death among cancer patients, no effective anti-cachectic treatment is currently available. In experimental cachectic animal models, aberrant activation of STAT3 in skeletal muscle has been found to contribute to muscle wasting. However, its clinical association, the factors regulating STAT3 activation, and the molecular mechanisms remain incompletely understood. Here, we show that an enhanced interaction between activated STAT3 and HSP90, which were observed in the skeletal muscle of cancer cachexia patients, is a crucial event for the development of cachectic muscle wasting. Administration of HSP90 inhibitors 17DMAG and PU-H71 alleviated the muscle wasting in C26 tumor-bearing cachectic mice or the myotube atrophy of C2C12 cells induced by C26 conditional medium. A mechanistic study indicated that in cachectic skeletal muscle, prolonged STAT3 activation transactivated FOXO1 by binding directly to its promoter and triggered the muscle wasting in a FOXO1-dependent manner; Our results demonstrate that the HSP90/STAT3/FOXO1 axis plays a critical role in the cachectic muscle wasting, which might serve as potential therapeutic target for the treatment of cancer cachexia.
Migraine is one of the most common of neurological disorders with a global prevalence of up to 15%. One in five migraineurs have frequent episodic or chronic migraine requiring prophylactic treatment. In recent years, specific pharmaceutical treatments targeting calcitonin gene-related peptide (CGRP) signalling molecules have provided safe and effective treatments; monoclonal antibodies for prophylaxis and gepants for acute therapy. Albeit the beneficious impact of these new drugs, it is important to understand the molecular mechanisms involved to better understand migraine pathophysiology and improve the therapy. Here we describe current views on the role of the CGRP family of peptides CGRP, calcitonin (CT), adrenomedullin (AM), amylin (AMY) and their receptors in the trigeminovascular system (TGV). All these molecules are present within the TGV system but differ in expression and localization. It is likely that they have different roles, which can be utilized in providing additional drug targets.
Sepsis causes multi-organ dysfunction and is a major cause of death in intensive care units, but there are no treatments that reverse the pathophysiological effects of sepsis. Vitamin C has antioxidant, anti-inflammatory, anticoagulant and immune modulatory actions, so is a potential treatment for sepsis. Recent clinical trials of high-doses of intravenous vitamin C (6-16 g/day) had variable effects. Since much higher doses are without side-effects in cancer and burns patients, we studied the effects of a mega-dose of intravenous sodium ascorbate (150 g/40 kg) in a clinically relevant ovine model of sepsis. This treatment dramatically improved the clinical state and over 3-7-h improved cardiovascular, pulmonary, hepatic and renal function and reduced body temperature. In a critically ill COVID-19 patient, intravenous sodium ascorbate (60 g) restored arterial pressure, improved renal function and increased arterial blood oxygen levels. Clinical trials are testing the effectiveness of mega-dose vitamin C in septic patients.
Alcohol use disorder (AUD) is one of the most common but still poorly treated psychiatric conditions. Developing new treatments requires a better understanding of the aetiology of symptoms and evaluation of novel therapeutic targets in preclinical studies. Recent developments in our understanding of the reinforcement-based cognitive biases (RBCBs) that contribute to the development of AUD and its treatment offer new opportunities for both clinical and preclinical research. In this review, we first briefly describe psychological and cognitive theories that implicate various aspects of reinforcement sensitivity in the development, maintenance, and recurrence of alcohol addiction. Furthermore, in separate sections, we describe studies investigating RBCBs and their neural, neurochemical, and pharmacological correlates, and we discuss possible interactions between RBCBs and trajectories of AUD. Finally, we describe how recent translational studies using state-of-the-art animal models can facilitate our understanding of the role of reinforcement sensitivity and RBCBs in various aspects of AUD.
Background and Purpose: Superoxide anions can reduce the bioavailability and actions of endothelium-derived NO. In human resistance-sized arteries, endothelium-dependent vasodilatation can be mediated by H2O2 instead of NO. We tested the hypotheses that in resistance arteries from patients with resistant cardiovascular disease (CVD), endothelium-dependent vasodilatation uses mechanisms that are either insensitive to oxidative stress or involve a reactive oxygen species. Experimental Approach: Small arteries were isolated from biopsies of the parietal pericardium of patients undergoing elective cardiothoracic surgery and were studied by immunohistochemical and organ chamber techniques. Key Results: NO-synthases 1, 2 and 3, superoxide dismutase 1 and catalase proteins were observed in the microvascular wall. Relaxing responses to bradykinin were endothelium dependent. During submaximal depolarization-induced contraction, these relaxations were inhibited by inhibitors of NO-synthases (NOS) and soluble guanylyl cyclase (sGC) but not by scavengers of NO or HNO, inhibitors of cyclooxygenases, neuronal NO-synthase, superoxide dismutase or catalase, or by exogenous catalase. During contraction stimulated by endothelin-1, these relaxations were not reduced by any of these interventions except DETCA which caused a small reduction. Conclusion and Implications: In resistance arteries from patients with resistant CVD, endothelium-dependent relaxations seem not to be mediated by NO, HNO or H2O2 although NOS and sGC can be involved. These vasodilator responses proceed during excessive oxidative stress.
Background and Purpose: Acute lung injury (ALI), acute respiratory distress syndrome (ARDS) and pulmonary fibrosis remain major causes of morbidity, mortality and healthcare burden in the critically ill patient. There is an urgent medical need for identifying factors of susceptibility and prognosis and for designing new therapeutic tools for treating these disorders. Here, we evaluate the capacity of the immunomodulatory neuropeptide cortistatin to regulate pulmonary inflammation and fibrosis in vivo. Experimental Approach: ALI/ARDS and pulmonary fibrosis were induced experimentally in wild-type and cortistatin-deficient mice by pulmonary infusion of the bacterial endotoxin LPS or the chemotherapeutic drug bleomycin, and the histopathological signs, pulmonary leukocyte infiltration and cytokines and fibrotic markers were evaluated. Key Results: Partially-deficient mice in cortistatin showed exacerbated pulmonary damage, pulmonary inflammation, alveolar oedema and fibrosis, and subsequent increased respiratory failure and mortality when challenged to LPS or bleomycin, even at low doses. Treatment with cortistatin reversed these aggravated phenotypes and protected from progression to severe ARDS and fibrosis after high-exposition to both injury agents. Moreover, cortistatin-deficient pulmonary macrophages and fibroblasts showed exaggerated ex vivo inflammatory and fibrotic responses. The anti-fibrotic protective effect of cortistatin was also observed in experimental scleroderma, in which lack of cortistatin predisposes to develop more severe dermal lesions and associated pulmonary fibrosis. Conclusion and Implications: We identify to cortistatin as an endogenous break of pulmonary inflammation and fibrosis. Deficiency in cortistatin could be a marker of poor-prognosis in inflammatory/fibrotic pulmonary disorders. Cortistatin-based therapies emerge as attractive candidates to treat severe ALI/ARDS, including SARS-Cov-2-associated ARDS.
Emerging data shows pregnant women with COVID-19 are at significantly higher risk of severe outcomes compared to non-pregnant women of similar age. This review discusses the invaluable insight revealed from vaccine clinical trials in women who were vaccinated and inadvertently became pregnant during the trial period. It further explores a number of clinical avenues in their management and proposes a drug development strategy in-line with clinical trials for vaccines and drug treatments for the drug development community. Little is known of the long-term effects of COVID-19 on the mother and the baby. We provide a rationale for our hypothesis that COVID-19 predisposes pregnant women to cardiovascular diseases later in life, in a similar way, to preeclampsia and may increase the risk of preeclampsia in their subsequent pregnancy. This is an ever-evolving landscape and early knowledge for healthcare providers and drug innovators is offered to ensure benefits outweigh the risks.
Background and Purpose: Many pain-triggering nociceptor neurons express TRPV1 or TRPA1, cation-selective channels with large pores that enable permeation of QX-314, a cationic analogue of lidocaine. Co-application of QX-314 with TRPV1 or TRPA1 activators can silence nociceptors. We now describe BW-031, a novel more potent cationic sodium channel inhibitor, test whether its application alone can inhibit the pain associated with tissue inflammation, and whether this strategy can also inhibit cough. Experimental Approach: We characterized BW-031 inhibition of sodium channels and tested BW-031 in three models of inflammatory pain: rat paw inflammation produced by Complete Freund’s Adjuvant injection or surgical incision and a mouse paw UV burn model. We also tested the ability of BW-031 to inhibit cough induced by inhalation of dilute citric acid in guinea pigs. Key Results: BW-031 inhibited Nav1.7 and Nav1.1 channels with ~6-fold greater potency than QX-314 when introduced inside cells and entered capsaicin-activated TRPV1 expressing sensory neurons. BW-031 inhibited inflammatory pain in all three models, producing more effective and longer-lasting inhibition of pain than QX-314 in the mouse UV burn model. BW-031 was also effective in reducing cough counts by 78-90% when applied intratracheally under isoflurane anesthesia or by aerosol inhalation in awake guinea pigs with airway inflammation produced by ovalbumin sensitization. Conclusion and Implications: BW-031 a novel cationic sodium channel inhibitor can be applied locally as a single agent to inhibit inflammatory pain and also effectively inhibits cough in a guinea pig model of nociceptor-activated cough, suggesting a new clinical approach to treating cough.
Background and Purpose: Individualized assessment of the activity of cytochrome P450 2D6 (CYP2D6), a highly variable drug-metabolizing enzyme, is performed through phenotyping during which a probe drug is administered to measure the enzyme’s activity. In order to avoid any iatrogenic harm (allergic drug reaction, dosing error) related to the probe drug, the development of non-invasive tools for real-time phenotyping of CYP2D6 could significantly contribute to the expansion of precision medicine in clinical practice. This study focuses on the identification of endogenous markers of the CYP2D6 enzyme in human biofluids using a liquid chromatography (LC)-high-resolution mass spectrometry (HRMS)-based metabolomics approach. Experimental Approach: Data from a control session were compared to data from an inhibition session. Before the latter, healthy volunteers (extensive and ultrarapid metabolizers) received a daily dose of paroxetine 20 mg over seven days. CYP2D6 genotyping and phenotyping, using single oral dose of dextromethorphan 5 mg, were also performed in all participants. Key Results: In CYP2D6 extensive and ultrarapid metabolizers (n = 37), mean relative intensities of five features were significantly reduced during the inhibition session compared to the control session (fold changes ≤ 0.67, FDR-adjusted P < 0.0001). Furthermore, mean relative intensities of these candidates were significantly higher in the CYP2D6 extensive-ultrarapid metabolizer group (n = 37) compared to the poor metabolizer group (n = 6) (fold changes ≤ 0.67, P < 0.0001). Conclusion and Implications: The applied untargeted metabolomics strategy was able to identify five CYP2D6 endogenous metabolites, a promising discovery for non-invasive phenotyping and personalised medicine.
Background and Purpose. Pseudomonas aeruginosa is a main cause of ventilator-associated pneumonia (VAP) with drug-resistant bacteria. Bacteriophage therapy has experienced resurgence to compensate for the limited development of novel antibiotics. However, phage therapy is limited to a compassionate use so far, resulting from lack of adequate studies in relevant pharmacological models. We used a pig model of VAP caused by P. aeruginosa that recapitulates essential features of human disease to study the antimicrobial efficacy of nebulized-phage therapy. Experimental Approach. (i) Lysis kinetic assays were performed to evaluate in vitro phage antibacterial efficacy against P. aeruginosa and select relevant combinations of lytic phages. (ii) The efficacy of the phage combinations was investigated in vivo (murine model of P. aeruginosa lung infection). (iii) We determined the optimal conditions to ensure efficient phage delivery by aerosol during mechanical ventilation. (iv) Lung antimicrobial efficacy of inhaled-phage therapy was evaluated in pigs, which were anesthetized, mechanically ventilated and infected with P. aeruginosa. Key Results. By selecting an active phage cocktail and optimizing aerosol delivery conditions, we were able to deliver high phage concentrations in the lungs, which resulted in a rapid and marked reduction in P. aeruginosa density (1.5 Log reduction, p<0.001). No phage was detected in the sera and urines throughout the experiment. Conclusion and Implications. Our findings demonstrated: (i) the feasibility of delivering large amounts of active phages by nebulization during mechanical ventilation, (ii) rapid control of in situ infection by inhaled bacteriophage in an experimental model of VAP with high translational value.
COVID-19 is a complex disease and many difficulties are faced today especially in the proper choice of pharmacological treatments. The role of antiviral agents for COVID-19 is still being investigated. The evidence for immunomodulatory and anti-inflammatory drugs is quite conflicting, while the use of corticosteroids is supported by robust evidence. The use of heparins in hospitalized critically ill patients is preferred over other anticoagulants. Lastly, conflicting data were found regarding to the use of convalescent plasma and vitamin D. According to data shared by the WHO, many vaccines are under phase 3 clinical trials and some of them already received the marketing approval in EU countries and in the US. In conclusion, drugs repurposing has represented the main approach recently used in the treatment of patients with COVID-19. At this moment, the analysis of efficacy and safety data of drugs and vaccines used in real life context is strongly needed.
Epilepsy is a common neurological disorder characterized by repeated and spontaneous epileptic seizures, which is not well controlled by current medication. Traditional theory supports that epilepsy results from the imbalance of excitatory glutamate neurons and inhibitory GABAergic neurons. Recently, shreds of evidence from available clinical and preclinical researches suggest that histamine in the central nervous system plays an important role in the modulation of neural excitability and pathogenesis of epilepsy. Many histamine receptor ligands show positive response in animal epilepsy models, among which the H3R antagonist pitolisant even has shown a good anti-epileptic effect in clinical trials. New insights are focusing on the potential action of histamine receptors to control and treat epilepsy. This review summarizes the findings from animal and clinical researches on the role of brain histamine and histamine receptor in epilepsy. Importantly, we further provide perspectives on some possible research directions for future studies.
Background and Purpose: The development of effective therapeutic strategies against Alzheimer’s disease (AD) remains a challenge. I2 Imidazoline receptors (I2-IR) ligands have a neuroprotective role in AD. While co-treatment of acetylcholinesterase inhibitors with neuroprotective agents have shown better effects on the prevention of dementia. Here, we assessed the potential therapeutic effect of the I2-IR ligand LSL60101, donepezil and their combination in 5XFAD mice. Experimental Approach: 5XFAD female mice were treated with low doses of LSL60101 (1mg/kg/day), donepezil (1mg/kg/day), and donepezil plus LSL60101 (1+1mg/kg/day), during 4 weeks per os. Novel object recognition, Morris water maze, open field, elevated plus maze and three-chamber tests were employed to evaluate the cognitive and behavioural status of the mice after treatment. The effects of the treatments on AD-like pathology were assessed with immunohistochemistry, Western blot and qPCR. Key results: Chronic low-dose treatment with LSL60101 and donepezil reversed cognitive deficits and impaired social behaviour. LSL60101 treatment did not affect anxiety-like behaviour in contrast to donepezil. In the 5XFAD brains, LSL60101 and donepezil/LSL60101 treatments decreased Aβ-pathology and Tau hyperphosphorylation, and these alterations were accompanied by decreased microglia marker Iba-1 levels and increased Trem2 gene expression. LSL60601 and donepezil decreased glial fibrillary acidic protein (GFAP) astrocytic marker reactivity. However, only LSL60601 treatment significantly increased the levels of the synaptic markers post-density 95 (PSD95) and synaptophysin (SYN). Conclusion and implications: Our results suggest that chronic low dose treatment with selective I2-IR ligands can be an effective treatment for AD and provide insights into combination treatments of symptomatic and disease-modifying drugs