Neuroinvasive potential of a primary respiratory pathogen SARS- CoV2: Summarizing the evidences

Neuromuscular defects after infection with a beta coronavirus in mice

COVID-19 affects primarily the lung. However, several other systemic alterations, including muscle weakness, fatigue and myalgia have been reported and may contribute to the disease outcome. We hypothesize that changes in the neuromuscular system may contribute to the latter symptoms observed in COVID-19 patients. Here, we showed that C57BL/6J mice inoculated intranasally with the murine betacoronavirus hepatitis coronavirus 3 (MHV-3), a model for studying COVID-19 in BSL-2 conditions that emulates severe COVID-19, developed robust motor alterations in muscle strength and locomotor activity. The latter changes were accompanied by degeneration and loss of motoneurons that were associated with the presence of virus-like particles inside the motoneuron. At the neuromuscular junction level, there were signs of atrophy and fragmentation in synaptic elements of MHV-3-infected mice. Furthermore, there was muscle atrophy and fiber type switch with alteration in myokines levels in muscles of MHV-3-infected mice. Collectively, our results show that acute infection with a betacoronavirus leads to robust motor impairment accompanied by neuromuscular system alteration.

The integrative process promoted by EMDR in dissociative disorders: neurobiological mechanisms, psychometric tools, and intervention efficacy on the psychological impact of the COVID-19 pandemic

Dissociative disorders (DDs) are characterized by a discontinuity in the normal integration of consciousness, memory, identity, emotion, perception, bodily representation, motor control, and action. The life-threatening coronavirus disease 2019 (COVID-19) pandemic has been identified as a potentially traumatic event and may produce a wide range of mental health problems, such as depression, anxiety disorders, sleep disorders, and DD, stemming from pandemic-related events, such as sickness, isolation, losing loved ones, and fear for one's life. In our conceptual analysis, we introduce the contribution of the structural dissociation of personality (SDP) theory and polyvagal theory to the conceptualization of the COVID-19 pandemic-triggered DD and the importance of assessing perceived safety in DD through neurophysiologically informed psychometric tools. In addition, we analyzed the contribution of eye movement desensitization and reprocessing (EMDR) to the treatment of the COVID-19 pandemic-triggered DD and suggest possible neurobiological mechanisms of action of the EMDR. In particular, we propose that, through slow eye movements, the EMDR may promote an initial non-rapid-eye-movement sleep stage 1-like activity, a subsequent access to a slow-wave sleep activity, and an oxytocinergic neurotransmission that, in turn, may foster the functional coupling between paraventricular nucleus and both sympathetic and parasympathetic cardioinhibitory nuclei. Neurophysiologically informed psychometric tools for safety evaluation in DDs are discussed. Furthermore, clinical and public health implications are considered, combining the EMDR, SDP theory, and polyvagal conceptualizations in light of the potential dissociative symptomatology triggered by the COVID-19 pandemic.

Correlation of covid-19 and Guillain-Barré syndrome: A Mechanistic Perspective

Aims

Coronaviruses, SARS-CoV-2 particles are spherical and have proteins called spikes that stick out on the surface. COVID-19 most commonly affects the respiratory system, but various clinical manifestations on coronavirus have revealed their potential neurotropism. The neuroinvasive affinity of Coronavirus infections has been reported nearly for all the β Coronavirus infections, including MERS-CoV, SARS-CoV, HCoV-OC43 and HEV. Coronavirus invasion occurs through hypoxia injury, immune injury, ACE2, and direct infection. The pathophysiology of SARS-CoV-2 and other human Coronaviruses reveals the possible mechanisms of neurodegeneration.

Methods

A systematic literature review carried out from various search engines like Scopus, PubMed, Medline, and Elsevier for investigating the therapeutic perspective of association between Covid-19 and Guillain-Barré syndrome.

Results

SARS-CoV-2 uses angiotensin-converting enzyme 2 as its entry receptor and enters the central nervous system through a Blood-brain barrier constituted of inflammatory mediators, direct infection of the endothelial cells, or endothelial injury. Guillain-Barré syndrome is an autoimmune disease that injures and attacks the nerves in the peripheral nervous system. Studies suggest that the virus can infect peripheral neurons to cause direct damage through various mechanisms, including direct damage by cytokine-related injury, ACE2 receptors, and the sequelae of hypoxia.

Conclusion

we have discussed the possible mechanisms between neuroinvasion of SARs-cov2 and Guillain-barre syndrome.

Emerging role of microRNAs and long non-coding RNAs in COVID-19 with implications to therapeutics

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection which is commonly known as COVID-19 (COronaVIrus Disease 2019) has creeped into the human population taking tolls of life and causing tremendous economic crisis. It is indeed crucial to gain knowledge about their characteristics and interactions with human host cells. It has been shown that the majority of our genome consists of non-coding RNAs. Non-coding RNAs including micro RNAs (miRNAs) and long non-coding RNAs (lncRNAs) display significant roles in regulating gene expression in almost all cancers and viral diseases. It is intriguing that miRNAs and lncRNAs remarkably regulate the function and expression of major immune components of SARS-CoV-2. MiRNAs act via RNA interference mechanism in which they bind to the complementary sequences of the viral RNA strand, inducing the formation of silencing complex that eventually degrades or inhibits the viral RNA and viral protein expression. LncRNAs have been extensively shown to regulate gene expression in cytokine storm and thus emerges as a critical target for COVID-19 treatment. These lncRNAs also act as competing endogenous RNAs (ceRNAs) by sponging miRNAs and thus affecting the expression of downstream targets during SARS-CoV-2 infection. In this review, we extensively discuss the role of miRNAs and lncRNAs, describe their mechanism of action and their different interacting human targets cells during SARS-CoV-2 infection. Finally, we discuss possible ways how an interference with their molecular function could be exploited for new therapies against SARS-CoV-2.

Suppression of porcine hemagglutinating encephalomyelitis virus replication by resveratrol

BACKGROUND

Porcine hemagglutinating encephalomyelitis virus (PHEV), a member of the genus Betacoronavirus, is the causative agent of neurological disease in pigs. No effective therapeutics are currently available for PHEV infection. Resveratrol has been shown to exert neuroprotective and antiviral effects. Here resveratrol was investigated for its ability to inhibit PHEV replication in nerve cells and central nervous system tissues.

METHODS

Anti-PHEV effect of resveratrol was evaluated using an in vitro cell-based PHEV infection model and employing a mouse PHEV infection model. The collected cells or tissues were used for quantitative PCR analysis, western blot analysis, or indirect immunofluorescence assay. The supernatants were collected to quantify viral loads by TCID₅₀ assay in vitro. EC50 and CC50 were determined by dose-response experiments, and the ratio (EC50/CC50) was used as a selectivity index (SI) to measure the antiviral versus cytotoxic activity.

RESULTS

Our results showed that resveratrol treatment reduced PHEV titer in a dose-dependent manner, with a 50% inhibition concentration of 6.24 μM. A reduction of > 70% of viral protein expression and mRNA copy number and a 19-fold reduction of virus titer were achieved when infected cells were treated with 10 µM resveratrol in a pre-treatment assay. Quantitative PCR analysis and TCID₅₀ assay results revealed that the addition of 10 μM resveratrol to cells after adsorption of PHEV significantly reduced 56% PHEV mRNA copy number and eightfold virus titer. 10 µM resveratrol treatment reduced 46% PHEV mRNA copy number and fourfold virus titer in virus inactivation assay. Moreover, the in vivo data obtained in this work also demonstrated that resveratrol inhibited PHEV replication, and anti-PHEV activities of resveratrol treatment via intranasal installation displayed better than oral gavage.

CONCLUSION

These results indicated that resveratrol exerted antiviral effects under various drug treatment and virus infection conditions in vitro and holds promise as a treatment for PHEV infection in vivo.

Antiviral effect of lysosomotropic disaccharide trehalose on porcine hemagglutinating encephalomyelitis virus, a highly neurotropic betacoronavirus

Many members of the genus Betacoronavirus are neurotropic viruses that frequently cause serious harm to humans or animals, including highly neurotropic porcine hemagglutinating encephalomyelitis virus (PHEV). Nevertheless, very few approved treatments exist to combat these viruses. Lysosomotropic trehalose, a widely used, nontoxic, natural disaccharide that can traverse the blood-brain barrier, has been proposed as a potential antiviral agent for use in prevention or treatment of betacoronavirus-associated infections. The purpose of this study was to determine if trehalose could inhibit PHEV infection of cells of a mouse central nervous system-derived neuroblastoma cell line in vitro or brain cells in vivo. Our results demonstrated that treatment of PHEV-infected mouse neuroblastoma cells and mice with trehalose reduced viral replication and that these trehalose antiviral effects were dependent on expression of lysosomal protein progranulin. Collectively, these results indicated that trehalose holds promise as a new antiviral agent for use in controlling neurotropic betacoronavirus infections.

Molecular signaling pathways, pathophysiological features in various organs, and treatment strategies in SARS-CoV2 infection

Cytokine storms and extra-activated cytokine signaling pathways can lead to severe tissue damage and patient death. Activation of inflammatory signaling pathways during Cytokine storms are an important factor in the development of acute respiratory syndrome (SARS-CoV-2), which is the major health problem today, causing systemic and local inflammation. Cytokine storms attract many inflammatory cells that attack the lungs and other organs and cause tissue damage. Angiotensin-converting enzyme 2 (ACE2) are expressed in a different type of tissues. inhibition of ACE2 activity impairs renin-angiotensin (RAS) function, which is related to the severity of symptoms and mortality rate in COVID-19 patients. Different signaling cascades are activated, affecting various organs during SARS-CoV-2 infection. Nowadays, there is no specific treatment for COVID-19, but scientists have recognized and proposed several treatment alternatives, including applying cytokine inhibitors, immunomodulators, and plasma therapy. Herein, we have provided the detailed mechanism of SARS-CoV-2 induced cytokine signaling and its connection with pathophysiological features in different organs. Possible treatment options to cope with the severe clinical manifestations of COVID-19 are also discussed.

Nitric Oxide in the Management of Respiratory Consequences in COVID-19: A Scoping Review of a Different Treatment Approach

The severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) virus causing COVID-19 significantly affects the respiratory functions of infected individuals by massively disrupting the pulmonary oxygenation and activating the synthesis of proinflammatory cytokines, inducing severe oxidative stress, enhanced vascular permeability, and endothelial dysfunction which have rendered researchers and clinicians to depend on prophylactic treatment due to the unavailability of proper disease management approaches. Previous studies have indicated that nitric oxide (NO) application appears to be significant concerning the antiviral activities, antioxidant, and anti-inflammatory properties in relieving disease-related symptoms. To identify, explore, and map the literature on the role of nitric oxide in the management of respiratory consequences in COVID-19 through this scoping review, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed during the search to answer the focal question: "What are the potential uses of nitric oxide in the management of respiratory failure in COVID-19?" Administering exogenous NO in the form of inhaled gas or stimulating the system to produce NO appears to be a suitable option to manage COVID-19-induced pneumonia and respiratory illness. This treatment modality seems to attenuate respiratory distress among patients suffering from severe infections or patients with comorbidities. Exogenous NO at different doses effectively reduces systemic hyperinflammation and oxidative stress, improves arterial oxygenation, and restores pulmonary alveolar cellular integrity to prevent the lungs and other organs from further damage. This therapy could pave the way for better management of COVID-19 before the onset of disease-related complications.

Central nervous system outcomes of COVID-19

The worldwide pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected an estimated 200 million people with over 4 million deaths. Although COVID-19, the disease caused by the SARS-CoV-2 virus, is primarily a respiratory disease, an increasing number of neurologic symptoms have been reported. Some of these symptoms, such as loss of smell or taste, are mild and non-life threatening, while others, such as stroke or seizure, are more critical. Many of these symptoms remain long after the acute illness has passed, a phenomenon known as "long COVID" or postacute sequelae of SARS-CoV-2 infection (PASC). Neurological symptoms can be difficult to study due to the complexity of the central and peripheral nervous system. These neurologic symptoms can be difficult to identify and quantitate. This narrative review will describe approaches for assessing neurologic manifestations of COVID-19, with examples of the data they provide, as well as some directions for future research to aid in understanding the pathophysiology of COVID-19-related neurological implications.

Neurological manifestations of COVID-19 in patients: from path physiology to therapy

Coronavirus is a family of ARN positive single-stranded belonging to the family of Coronaviridae. There are several families of coronavirus that transmit more or less serious diseases. However, the so-called coronavirus-19 (SARS-CoV2) is the one that is currently causing most of the problems; in fact, biological dysfunctions that this virus causes provoke damage in various organs, from the lung to the heart, the kidney, the circulatory system, and even the brain. The neurological manifestations caused by viral infection, as well as the hypercoagulopathy and systemic inflammation, have been reported in several studies. In this review, we update the neurological mechanisms by which coronavirus-19 causes neurological manifestation in patients such as encephalomyelitis, Guillain-Barré syndrome, lacunars infarcts, neuropsychiatry disorders such as anxiety and depression, and vascular alterations. This review explains (a) the possible pathways by which coronavirus-19 can induce the different neurological manifestations, (b) the strategies used by the virus to cross the barrier system, (c) how the immune system responds to the infection, and (d) the treatment than can be administered to the COVID-19 patients.

The furin-S2' site in avian coronavirus plays a key role in central nervous system damage progression

The furin cleavage site plays an important role in virus pathogenicity. The spike protein of SARS-CoV-2 harbors a furin cleavage site insertion in contrast to SARS-CoV, which may be related to its stronger communicability. An avian coronavirus with an extra furin cleavage site upstream of the fusion peptide (S2' site) infected monocyte cells and neuron cells leading to viremia or encephalitis, respectively. Immunohistochemistry and real-time quantitative polymerase chain reaction were used to follow disease progression and demonstrated differences between the parent avian coronavirus and mutated avian coronavirus with a furin-S2' site. Magnetic resonance imaging and biological dye to evaluate the blood-brain barrier permeability showed that avian coronavirus with a furin-S2' site had increased permeability compared with parent avian coronavirus. Immunohistochemistry of brains after intracerebral injection of avian coronavirus and immunofluorescence staining of primary neuron cells demonstrated the furin-S2' site expanded the cell tropism of the mutant avian coronavirus to neuron cells. TNF-α, which has a key role in blood-brain barrier permeability, was highly induced by avian coronavirus with a furin-S2' site compared with the parent avian coronavirus. We demonstrated the process involved in mutant avian coronavirus-induced disease and that the addition of a furin-S2' site changed the virus cell tropism.IMPORTANCECoronaviruses have broken out three times in two decades. Spike (S) protein plays a key role in the process of infection. To clarify importance of furin cleavage site in spike protein for coronavirus, we investigated the pathogenesis of neurotropic avian coronavirus whose spike protein contains an extra furin cleavage site (furin-S2' site). By combining real-time quantitative polymerase chain reaction and immunohistochemistry we demonstrated that infectious bronchitis virus (IBV) infects brain instead of trachea when its S protein contains furin-S2' site. Moreover, the virus was shown to increase the permeability of blood-brain barrier, infect neuron cells and induce high expression of TNF-α. Based on these results we further show that furin cleavage site in S protein plays an important role in coronavirus pathogenicity and cell tropism. Our study extends previous publications on function of S protein of coronavirus, increasing the understanding of researchers to coronavirus.

Optic Nerve Head Parameters and Peripapillary Retinal Nerve Fiber Layer Thickness in Patients with Coronavirus Disease 2019

Purpose: To quantify the optic nerve head (ONH) and peripapillary retinal nerve fiber layer (pRNFL) thickness in patients with Coronavirus Disease-2019 (COVID-19) and compare the measurements with a healthy control group.Methods: In a comparative cross-sectional observational study, ONH and pRNFL thickness were evaluated in patients with a history of COVID-19, at least 2 weeks after recovery from the systemic disease, and compared with an age-matched, normal control group.Results: Thirty COVID-19 patients along with 60 age- and gender-matched healthy controls were studied. Mean average pRNFL thickness was 105.0 ± 16.3 µm in the COVID-19 patients, compared to 99.0 ± 9.0 µm in the controls (p = .31). The pRNFL thicknesses in all sectors was higher in patients with a history of COVID-19; however, this did not reach statistical significance. Similarly, ONH parameters were not significantly different between the groups.Conclusion: Patients recovered from COVID-19 had unremarkable alterations in the peripapillary RNFL thickness.Abbreviations: ONH: Optic Nerve HeadRNFL: Retinal Nerve Fiber LayerSD-OCT: Spectral-Domain Optical Coherence TomographyCOVID-19: Coronavirus Disease 2019SARS-CoV-2: Severe Acute Respiratory Syndrome Coronavirus 2CNS: Central Nervous SystemACE: Angiotensin-Converting EnzymeRT-PCR: Reverse Transcription-Polymerase Chain Reaction.

Neurocognitive deficits in severe COVID-19 infection: Case series and proposed model

Objective: To date, very few studies investigating neurocognitive deficits in COVID-19 have been published. This case series addresses cognition in post-COVID-19 patient by describing three patients in acute rehabilitation to inform a model of cognitive sequelae of COVID-19. Methods: Three English-speaking inpatients with severe symptoms and long-term intensive care unit (ICU) treatment are described. All patients had a premorbid history of hypertension and hyperlipidemia and experienced delirium and hypoxemia when hospitalized. Patient 1 is a 62-year-old male with 15 years of education with additional history of obstructive sleep apnea and type 2 diabetes. Patient 2 is a 73-year-old female with 12 years of education with a premorbid medical history of alcohol use disorder and Guillain-Barre syndrome. Patient 3 is a 75-year-old male with 14 years of education. No patients had premorbid psychiatric histories. Results: The three patients demonstrated deficits on formal neuropsychological testing, particularly with encoding and verbal fluency. Memory measures improved with a more structured story memory task compared to a less-structured verbal list-learning task, suggesting executive dysfunction impacted learning. None of the patients demonstrated rapid forgetting of information. Two patients endorsed new depressive and/or anxiety symptoms. Conclusions: The results suggest evidence for neurocognitive deficits after severe COVID-19 infection, particularly in encoding and verbal fluency. These results were interpreted with caution given the limited number of patients and the telephone-based battery. The specific mechanism that caused these cognitive deficits in these individuals remains unclear. A proposed three-stage model of cognitive dysfunction is described to help guide future research.

Identification of Novel Hypothalamic MicroRNAs as Promising Therapeutics for SARS-CoV-2 by Regulating ACE2 and TMPRSS2 Expression: An In Silico Analysis

BACKGROUND

Neuroinvasion of severe acute respiratory syndrome coronavirus (SARS-CoV) is well documented and, given the similarities between this virus and SARS-CoV-2, it seems that the neurological impairment that is associated with coronavirus disease 2019 (COVID-19) is due to SARS-CoV-2 neuroinvasion. Hypothalamic circuits are exposed to the entry of the virus via the olfactory bulb and interact centrally with crucial respiratory nuclei. Hypothalamic microRNAs are considered as potential biomarkers and modulators for various diseases and future therapeutic targets. The present study aims to investigate the microRNAs that regulate the expression of hypothalamic angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), essential elements for SARS-CoV-2 cell entry.

METHODS

To determine potential hypothalamic miRNAs that can directly bind to ACE2 and TMPRSS2, multiple target bioinformatics prediction algorithms were used, including miRBase, Target scan, and miRWalk2.029.

RESULTS

Our in silico analysis has revealed that, although there are over 5000 hypothalamic miRNAs, around 31 miRNAs and 29 miRNAs have shown binding sites and strong binding capacity against ACE2 and TMPRSS2, respectively.

CONCLUSION

These novel potential hypothalamic miRNAs can be used to identify new therapeutic targets to treat neurological symptoms in COVID-19 patients via regulation of ACE2 and TMPRSS2 expression.

SARS-CoV-2-Associated Acute Hemorrhagic, Necrotizing Encephalitis (AHNE) Presenting with Cognitive Impairment in a 44-Year-Old Woman without Comorbidities: A Case Report

Patient: Female, 44-year-old

Final Diagnosis: COVID-19

Symptoms: Confusion

Medication:—

Clinical Procedure: —

Specialty: Neurology