Human coronaviruses: viral and cellular factors involved in neuroinvasiveness and neuropathogenesis

Distinct Replication Kinetics, Cytopathogenicity, and Immune Gene Regulation in Human Microglia Cells Infected with Asian and African Lineages of Zika Virus

Zika virus (ZIKV), a mosquito-borne flavivirus, is a significant global health concern due to its association with neurodevelopmental disorders such as congenital Zika syndrome (CZS). This study aimed to compare the replication kinetics, viral persistence, cytopathogenic effects, and immune gene expression in human microglia cells (CHME-3) infected with an Asian lineage ZIKV (PRVABC59, referred to as ZIKV-PRV) and an African lineage ZIKV (IBH30656, referred to as ZIKV-IBH). We found that ZIKV-PRV replicated more efficiently and persisted longer while inducing lower levels of cell death and inflammatory gene activation compared with ZIKV-IBH. These findings suggest that the enhanced replication and persistence of ZIKV-PRV, along with its ability to evade innate immune responses, may underlie its increased neuropathogenic potential, especially in the context of CZS. In contrast, ZIKV-IBH, with its stronger immune gene activation and higher cytopathogenicity, may lead to more acute infections with faster viral clearance, thereby reducing the likelihood of chronic central nervous system (CNS) infection. This study provides crucial insights into the molecular and cellular mechanisms driving the differential pathogenicity of ZIKV lineages and highlights the need for further research to pinpoint the viral factors responsible for these distinct clinical outcomes.

Gender Disparities in Neurological Symptoms of Long COVID: A Systematic Review and Meta-Analysis

BACKGROUND

Female gender is a known risk factor for long COVID. With the increasing number of COVID-19 cases, the corresponding number of survivors is also expected to rise. To the best of our knowledge, no systematic review has specifically addressed the gender differences in neurological symptoms of long COVID.

METHODS

We included studies on female individuals who presented with specific neurological symptoms at least 12 weeks after confirmed COVID-19 diagnosis from PubMed, Central, Scopus, and Web of Science. The search limit was put for after January 2020 until June 15, 2024. We excluded studies that did not provide sex-specific outcome data, those not in English, case reports, case series, and review articles Results: A total of 5,632 eligible articles were identified. This article provides relevant information from 12 studies involving 6,849 patients, of which 3,414 were female. The sample size ranged from 70 to 2,856, with a maximum follow-up period of 18 months. The earliest publication date was September 16, 2021, while the latest was June 11, 2024. The following neurological symptoms had a significant difference in the risk ratio (RR) for female gender: fatigue RR 1.40 (95% confidence interval [CI]: 1.22-1.60, p < 0.001), headache RR 1.37 (95% CI: 1.12-1.67, p = 0.002), brain-fog RR 1.38 (95% CI 1.08-1.76, p = 0.011) depression RR 1.49 (95% CI: 1.2-1.86, p < 0.001), and anosmia RR 1.61 (95% CI: 1.36-1.90, p < 0.001). High heterogenicity was found for fatigue, brain fog, and anxiety due to the diverse methodologies employed in the studies.

CONCLUSION

Our findings suggest that women are at a higher risk for long-COVID neurological symptoms, including fatigue, headaches, brain fog, depression, and anosmia, compared to men. The prevalence of these symptoms decreases after 1 year, based on limited data from the small number of studies available beyond this period.

Significance of Persistent Systemic Support in the Clinical Course of Delayed Post-hypoxic Leukoencephalopathy Following Severe Coronavirus Disease 2019

A 45-year-old woman was hospitalized with severe coronavirus disease 2019 pneumonia. Following cytokine storm-induced multiorgan failure and lethal arrhythmia, the patient developed a sustained coma with flaccid quadriplegia. A cerebrospinal fluid examination excluded infectious and immunogenic encephalopathies, and diffusion-weighted magnetic resonance imaging demonstrated high-intensity areas in the white matter with a cortex-sparing distribution, suggesting delayed post-hypoxic leukoencephalopathy. As a result of intensive cardiopulmonary support for a month, the neurological function gradually recovered. Based on the reversible clinical course noted in this patient, accurate diagnosis and persistent medical approaches are important for the management of coronavirus disease 2019-related delayed post-hypoxic leukoencephalopathy.

Long term outcomes of hyperbaric oxygen therapy in post covid condition: longitudinal follow-up of a randomized controlled trial

In our previous randomized controlled trial, we documented significant improvements in cognitive, psychiatric, fatigue, sleep, and pain symptoms among long Coronavirus disease 2019 (COVID) patients who underwent hyperbaric oxygen therapy (HBOT). The primary objective of the present study was to evaluate the enduring 1 year long term effects of HBOT on long COVID syndrome. This longitudinal long-term follow-up included 31 patients with reported post COVID-19 cognitive symptoms, who underwent 40 daily sessions of HBOT. Participants were recruited more than one year (486 ± 73) after completion of the last HBOT session. Quality of life, assessed using the short form-36 (SF-36) questionnaire revealed, that the long-term results exhibited a similar magnitude of improvement as the short-term outcomes following HBOT across most domains. Regarding sleep quality, improvements were observed in global score and across five sleep domains with effect sizes of moderate magnitude during the short-term evaluation, and these improvements persisted in the long-term assessment (effect size (ES1) = 0.47-0.79). In the realm of neuropsychiatric symptoms, as evaluated by the brief symptom inventory-18 (BSI-18), the short-term assessment following HBOT demonstrated a large effect size, and this effect persisted at the long-term evaluation. Both pain severity (ES1 = 0.69) and pain interference (ES1 = 0.83), had significant improvements during the short-term assessment post HBOT, which persisted at long term. The results indicate HBOT can improve the quality of life, quality of sleep, psychiatric and pain symptoms of patients suffering from long COVID. The clinical improvements gained by HBOT are persistent even 1 year after the last HBOT session.

Elevated matrix metalloproteinase‑9 expression is associated with COVID‑19 severity: A meta‑analysis

The present meta-analysis investigated the clinical value of serum matrix metalloproteinase (MMP)-9 levels in Coronavirus Disease 2019 (COVID-19) patients. Studies assessing the outcomes of patients with COVID-19 in correlation with the MMP-9 levels were retrieved from PubMed, Web of Science, EMBASE, Cochrane, WANFANG, and CNKI. A meta-analysis was performed to compare the serum MMP-9 levels between different patient groups: Severe vs. non-severe; acute respiratory distress syndrome (ARDS) vs. non-ARDS; non-survivors vs. survivors; neurologic syndrome vs. non-neurologic syndrome; and obese diabetic vs. non-obese diabetic. A total of 2,062 COVID-19-confirmed patients from 12 studies were included in this meta-analysis. The serum MMP-9 levels were significantly higher in patients with severe COVID-19 than in those with non-severe COVID-19 [weighted mean difference (WMD) 246.61 (95% confidence interval (CI), 115.86-377.36), P<0.001]. Patients with ARDS exhibited significantly higher MMP-9 levels than those without ARDS [WMD 248.55 (95% CI, 63.84-433.25), P<0.001]. The MMP-9 levels in the non-survivors did not significantly differ from those in the survivors [WMD 37.79 (95% CI, -18.08-93.65), P=0.185]. Patients with comorbidities, including neurological syndromes, and obese diabetic patients had significantly higher MMP-9 levels than those without comorbidities [WMD 170.73 (95% CI, 95.61-245.85), P<0.001]. Serum MMP-9 levels were associated with COVID-19 severity and may serve as a therapeutic target for improving the prognosis of patients with COVID-19.

COVID-19 and Alzheimer's Disease Share Common Neurological and Ophthalmological Manifestations: A Bidirectional Risk in the Post-Pandemic Future

A growing body of evidence indicates that a neuropathological cross-talk takes place between the coronavirus disease 2019 (COVID-19) -the pandemic severe pneumonia that has had a tremendous impact on the global economy and health since three years after its outbreak in December 2019- and Alzheimer's Disease (AD), the leading cause of dementia among human beings, reaching 139 million by the year 2050. Even though COVID-19 is a primary respiratory disease, its causative agent, the so-called Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), is also endowed with high neuro-invasive potential (Neurocovid). The neurological complications of COVID-19, resulting from the direct viral entry into the Central Nervous System (CNS) and/or indirect systemic inflammation and dysregulated activation of immune response, encompass memory decline and anosmia which are typically associated with AD symptomatology. In addition, patients diagnosed with AD are more vulnerable to SARS-CoV-2 infection and are inclined to more severe clinical outcomes. In the present review, we better elucidate the intimate connection between COVID-19 and AD by summarizing the involved risk factors/targets and the underlying biological mechanisms shared by these two disorders with a particular focus on the Angiotensin-Converting Enzyme 2 (ACE2) receptor, APOlipoprotein E (APOE), aging, neuroinflammation and cellular pathways associated with the Amyloid Precursor Protein (APP)/Amyloid beta (Aβ) and tau neuropathologies. Finally, the involvement of ophthalmological manifestations, including vitreo-retinal abnormalities and visual deficits, in both COVID-19 and AD are also discussed. Understanding the common physiopathological aspects linking COVID-19 and AD will pave the way to novel management and diagnostic/therapeutic approaches to cope with them in the post-pandemic future.

SARS-CoV-2 and Brain Health: New Challenges in the Era of the Pandemic

Respiratory viral infections have been found to have a negative impact on neurological functions, potentially leading to significant neurological impairment. The SARS-CoV-2 virus has precipitated a worldwide pandemic, posing a substantial threat to human lives. Growing evidence suggests that SARS-CoV-2 may severely affect the CNS and respiratory system. The current prevalence of clinical neurological issues associated with SARS-CoV-2 has raised significant concerns. However, there needs to be a more comprehensive understanding of the specific pathways by which SARS-CoV-2 enters the nervous system. Based on the available evidence, this review focuses on the clinical neurological manifestations of SARS-CoV-2 and the possible mechanisms by which SARS-CoV-2 invades the brain.

Complications of COVID-19 on the Central Nervous System: Mechanisms and Potential Treatment for Easing Long COVID

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invades human cells by binding to the angiotensin-converting-enzyme-2 (ACE-2) using a spike protein and leads to Coronavirus disease-2019 (COVID-19). COVID-19 primarily causes a respiratory infection that can lead to severe systemic inflammation. It is also common for some patients to develop significant neurological and psychiatric symptoms. The spread of SARS-CoV-2 to the CNS likely occurs through several pathways. Once spread in the CNS, many acute symptoms emerge, and such infections could also transpire into severe neurological complications, including encephalitis or ischemic stroke. After recovery from the acute infection, a significant percentage of patients develop "long COVID," a condition in which several symptoms of COVID-19 persist for prolonged periods. This review aims to discuss acute and chronic neurological problems after SARS-CoV-2 infection. The potential mechanisms by which SARS-CoV-2 enters the CNS and causes neuroinflammation, neuropathological changes observed in post-mortem brains of COVID-19 patients, and cognitive and mood problems in COVID-19 survivors are discussed in the initial part. The later part of the review deliberates the causes of long COVID, approaches for noninvasive tracking of neuroinflammation in long COVID patients, and the potential therapeutic strategies that could ease enduring CNS symptoms observed in long COVID.

Insights into COVID-19: Perspectives on Drug Remedies and Host Cell Responses

In light of the COVID-19 global pandemic caused by SARS-CoV-2, ongoing research has centered on minimizing viral spread either by stopping viral entry or inhibiting viral replication. Repurposing antiviral drugs, typically nucleoside analogs, has proven successful at inhibiting virus replication. This review summarizes current information regarding coronavirus classification and characterization and presents the broad clinical consequences of SARS-CoV-2 activation of the angiotensin-converting enzyme 2 (ACE2) receptor expressed in different human cell types. It provides publicly available knowledge on the chemical nature of proposed therapeutics and their target biomolecules to assist in the identification of potentially new drugs for the treatment of SARS-CoV-2 infection.

Relation between Guillain-Barré syndrome and Covid-19: Case-Series

Approximately two-thirds of the Guillain-Barré syndrome (GBS) cases are preceded by upper respiratory tract infection or enteritis. There has been previous documentation of a clear association between Covid-19 and GBS. Covid-19 can affect the nervous tissue either through direct damage or through triggering a host immune response with subsequent development of autoimmune diseases such as GBS. Covid-19 can affect the host`s immune system through the activation and interaction of the T-and B-lymphocytes with subsequent production of antibodies that cross-react with the gangliosides. Depending on the nature of the neuronal autoimmune destruction, the affected individual may have either a demyelinating or axonal subtype of GBS. These subtypes differ not only in symptoms but also in the likelihood of recovery. This report presents two cases of GBS that developed after the respiratory symptoms of Covid-19. Their neurological features indicated demyelination, axonal damage, irritation of spinal nerve roots, and impaired sensory and motor transmission with additional facial nerve palsy in the second-studied case. This case report highlights the relationship between GBS and Covid-19 infection.

Effect of famotidine on cognitive and behavioral dysfunctions induced in post-COVID-19 infection: A randomized, double-blind, and placebo-controlled study

OBJECTIVES

This is an investigation of the efficacy and safety of famotidine, a selective histamine H2 receptor antagonist, on improvement of cognitive impairment, depression and anxiety symptoms developing post-COVID-19, in a 12-week, randomized controlled trial.

METHODS

A total of 50 patients with a confirmed diagnosis of COVID-19 and a score ≤ 23 on the Mini-Mental State Examination (MMSE) test or a score ≤ 22 on the Montreal Cognitive Assessment (MoCA) were randomly assigned to either the famotidine (40 mg twice daily) or the placebo group. Changes in MMSE scores at weeks 6 and 12 were the primary outcome, while changes in other scales were the secondary outcomes. Participants and evaluators were blinded.

RESULTS

At weeks 6 and 12, patients in the famotidine group had significantly higher MMSE scores (p = 0.014, p < 0.001, respectively). Regarding the MoCA scale, the famotidine group had a significantly higher score at weeks 6 and 12 (p = 0.001, p < 0.001, respectively). Considering the HAM-D scale (Hamilton Depression Rating Scale), at weeks 6 and 12, the famotidine group experienced a larger reduction (p = 0.009, p = 0.02, respectively). Additionally, comparison of the HAM-A scale scores (Hamilton Anxiety Rating Scale) at weeks 6 and 12 showed a statistically significant larger reduction in the famotidine group (p = 0.04, p = 0.02, respectively). The two groups did not differ in the frequency of adverse effects.

CONCLUSION

Our study supports safety and efficacy of famotidine in treating cognitive impairment, depression and anxiety symptoms induced by COVID-19.

TRIAL REGISTRATION

This trial was registered at the Iranian registry of clinical trials (IRCT: www.irct.ir; registration number: IRCT20090117001556N138).

Recapitulation of pathophysiological features of AD in SARS-CoV-2-infected subjects

Infection with the etiological agent of COVID-19, SARS-CoV-2, appears capable of impacting cognition in some patients with post-acute sequelae of SARS-CoV-2 (PASC). To evaluate neuropathophysiological consequences of SARS-CoV-2 infection, we examine transcriptional and cellular signatures in the Brodmann area 9 (BA9) of the frontal cortex and the hippocampal formation (HF) in SARS-CoV-2, Alzheimer's disease (AD), and SARS-CoV-2-infected AD individuals compared to age- and gender-matched neurological cases. Here, we show similar alterations of neuroinflammation and blood-brain barrier integrity in SARS-CoV-2, AD, and SARS-CoV-2-infected AD individuals. Distribution of microglial changes reflected by the increase in Iba-1 reveals nodular morphological alterations in SARS-CoV-2-infected AD individuals. Similarly, HIF-1α is significantly upregulated in the context of SARS-CoV-2 infection in the same brain regions regardless of AD status. The finding may help in informing decision-making regarding therapeutic treatments in patients with neuro-PASC, especially those at increased risk of developing AD.

The Effects of Extrinsic and Intrinsic Factors on Neurogenesis

In the mammalian brain, neurogenesis is maintained throughout adulthood primarily in two typical niches, the subgranular zone (SGZ) of the dentate gyrus and the subventricular zone (SVZ) of the lateral ventricles and in other nonclassic neurogenic areas (e.g., the amygdala and striatum). During prenatal and early postnatal development, neural stem cells (NSCs) differentiate into neurons and migrate to appropriate areas such as the olfactory bulb where they integrate into existing neural networks; these phenomena constitute the multistep process of neurogenesis. Alterations in any of these processes impair neurogenesis and may even lead to brain dysfunction, including cognitive impairment and neurodegeneration. Here, we first summarize the main properties of mammalian neurogenic niches to describe the cellular and molecular mechanisms of neurogenesis. Accumulating evidence indicates that neurogenesis plays an integral role in neuronal plasticity in the brain and cognition in the postnatal period. Given that neurogenesis can be highly modulated by a number of extrinsic and intrinsic factors, we discuss the impact of extrinsic (e.g., alcohol) and intrinsic (e.g., hormones) modulators on neurogenesis. Additionally, we provide an overview of the contribution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to persistent neurological sequelae such as neurodegeneration, neurogenic defects and accelerated neuronal cell death. Together, our review provides a link between extrinsic/intrinsic factors and neurogenesis and explains the possible mechanisms of abnormal neurogenesis underlying neurological disorders.

Detection of SARS-CoV-2 viral proteins and genomic sequences in human brainstem nuclei

Neurological manifestations are common in COVID-19, the disease caused by SARS-CoV-2. Despite reports of SARS-CoV-2 detection in the brain and cerebrospinal fluid of COVID-19 patients, it is still unclear whether the virus can infect the central nervous system, and which neuropathological alterations can be ascribed to viral tropism, rather than immune-mediated mechanisms. Here, we assess neuropathological alterations in 24 COVID-19 patients and 18 matched controls who died due to pneumonia/respiratory failure. Aside from a wide spectrum of neuropathological alterations, SARS-CoV-2-immunoreactive neurons were detected in the dorsal medulla and in the substantia nigra of five COVID-19 subjects. Viral RNA was also detected by real-time RT-PCR. Quantification of reactive microglia revealed an anatomically segregated pattern of inflammation within affected brainstem regions, and was higher when compared to controls. While the results of this study support the neuroinvasive potential of SARS-CoV-2 and characterize the role of brainstem inflammation in COVID-19, its potential implications for neurodegeneration, especially in Parkinson's disease, require further investigations.

The value of chest X-ray and CT severity scoring systems in the diagnosis of COVID-19: A review

Coronavirus disease 2019 (COVID-19) is caused by a coronavirus family member known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The main laboratory test to confirm the quick diagnosis of COVID-19 infection is reverse transcription-polymerase chain reaction (RT-PCR) based on nasal or throat swab sampling. A small percentage of false-negative RT-PCR results have been reported. The RT-PCR test has a sensitivity of 50-72%, which could be attributed to a low viral load in test specimens or laboratory errors. In contrast, chest CT has shown 56-98% of sensitivity in diagnosing COVID-19 at initial presentation and has been suggested to be useful in correcting false negatives from RT-PCR. Chest X-rays and CT scans have been proposed to predict COVID-19 disease severity by displaying the score of lung involvement and thus providing information about the diagnosis and prognosis of COVID-19 infection. As a result, the current study provides a comprehensive overview of the utility of the severity score index using X-rays and CT scans in diagnosing patients with COVID-19 when compared to RT-PCR.

Short-term evaluation of motor and sensory nerve conduction parameters in COVID-19-associated peripheral neuropathy patients

Background

Severe acute respiratory syndrome coronavirus 2 (SARS‐COV‐2) is mostly associated with upper and lower respiratory tract manifestations. However, coronavirus disease 19 (COVID-19) can result in a wide range of other systemic symptomatology, including neuropsychiatric, psychological, and psychosocial impairments. Literature regarding neurological compromise, including neuropathy and sensory and motor affection associated with COVID-19, is still limited.

This study aims to evaluate the sensory, motor neuropathy, and secondary neurological impairment among patients with mild to moderate coronavirus disease associated with peripheral neuropathy within 1 month.

Methods

Forty participants, including 20 mild to moderate COVID-19 patients with peripheral neuropathy and 20 age and gender-matched healthy volunteers, were recruited in this case/control study. Laboratory evaluation focused on C-reactive protein (CRP) and D-dimer levels. Oxygen saturation for all participants was recorded. The neurophysiological study included motor nerve study, sensory nerve study, and F wave study for upper and lower limbs were done.

Results

The two groups were similar regarding baseline data. Neurological symptoms’ onset in the COVID-19 group ranged from 4 to 24 days. Levels of CRP and D-dimer levels were significantly higher in patients versus the control group. Motor nerve conduction (MNC) amplitude and latency for the median nerve were significantly compromised among the COVID-19 group. The MNC latency and F wave latency for the posterior tibial nerve were significantly higher in the COVID-19 group. The CRP and D-dimer levels were associated with a significant positive correlation with a latency of median nerve MNC, sensory nerve conduction (SNC), and f-wave; latency of MNC and F wave of the posterior tibial nerve; and SNC latency for sural nerve.

Conclusion

neurological involvement can occur in mild to moderate cases of SARS-COV-2 infection and add to the burden of the disease. Neurological symptoms in the course of COVID-19 disease should be interpreted cautiously, and appropriate diagnosis, including nerve conduction studies and management, should be considered.

Trial registration

ClinicalTrials.gov. NCT05721040.

Profiles of Independent-Comorbidity Groups in Senior COVID-19 Patients Reveal Low Fatality Associated with Standard Care and Low-Dose Hydroxychloroquine over Antivirals

Introduction

The lack of feasible therapies and comorbidities aggravate the COVID-19 case-fatality rate (CFR). However, reports examining CFR associations with diabetes, concomitant cardiovascular diseases, chronic kidney disease, and chronic liver disease (CLD) are limited. More studies assessing hydroxychloroquine (Hcq) and antivirals are needed.

Purpose

To examine associations of COVID-19 CFR in comorbid patient groups each with single comorbidities and after treatment with Hcq, favipiravir, and dexamethasone (Dex), either alone or in combination versus standard care.

Methods

Using statistical analysis, we descriptively determined these associations among 750 COVID-19 patient groups during the last quarter of 2021.

Results

A diabetes comorbidity (40%, n=299) showed twice the fatality (CFR 14%) of the others (CFR 7%; P=0.001). Hypertension (Htn) was the second-commonest comorbidity (29.5%, n=221), with similar CFR to diabetes (15% and 7% for Htn and non-Htn, respectively), but with higher significance (P=0.0006167). Although only 4% (n=30) heart failure (HF) was reported, the CFR (40%) was much higher than in those without it (8%). A similar rate (4%) for chronic kidney disease was reported, with CFRs of 33% and 9% among those with and without it, respectively (P=0.00048). Ischemic heart disease was 11% (n=74), followed by chronic liver disease (0.4%) and history of smoking (1%); however, these were not significant due to the sample sizes. Treatment indicated standard care and Hcq alone or in combination were superior (CFR of 4% and 0.5%, respectively) compared to favipiravir (25%) or Dex (38.5%) independently or in combination (35.4%). Furthermore, Hcq performed well (CFR 9%) when combined with Dex (9%; P=4.28-²⁶).

Conclusion

The dominance of diabetes and other comorbidities with significant association with CFR implied existence of a common virulence mechanism. The superiority of low-dose Hcq and standard care over antivirals warrants further studies.

Association of the matrix metalloproteinases (MMPs) family gene polymorphisms and the risk of coronavirus disease 2019 (COVID-19); implications of contribution for development of neurological symptoms in the COVID-19 patients

BACKGROUND

Seemingly, the Matrix metalloproteinases (MMPs) play a role in the etiopathogenesis of coronavirus disease 2019 (COVID-19). Here in this study, we determined the association of MMP9 rs3918242, MMP3 rs3025058, and MMP2 rs243865 polymorphisms with the risk of COVID-19, especially in those with neurological syndrome (NS).

METHODS

We enrolled 500 patients with COVID-19 and 500 healthy individuals. To genotype the target SNPs, the Real-time allelic discrimination technique was used. To determine serum levels of MMPs, Enzyme-linked immunosorbent assay (ELISA) was exerted.

RESULTS

The MMP9 gene rs3918242 and MMP3 gene rs3025058 SNP were significantly associated with increased COVID-19 risk and susceptibility to COVID-19 with NS. The serum level of MMP-9 and MMP-3 was significantly higher in COVID-19 cases compared with the healthy controls. Serum MMP-9 and MMP-3 levels were also higher in COVID-19 subjects with NS in comparison to the healthy controls. The polymorphisms in MMP genes were not associated with serum level of MMPs.

CONCLUSION

MMP9 and MMP3 gene polymorphisms increases the susceptibility to COVID-19 as well as COVID-19 with neurologic syndrome, but they probably have no role in the regulation of serum MMP-9 and MMP-3 levels.

A case of dysautonomia after COVID-19 infection in a patient with poorly controlled type I diabetes

COVID-19 has been linked to dysautonomia in the current literature, as has uncontrolled diabetes. Here, we present a case report of severe dysautonomia following a COVID-19 infection in a patient with pre-existing poorly controlled type-1 diabetes. This patient exhibited symptoms consistent with both postural orthostatic tachycardia syndrome (POTS), as well as orthostatic hypotension. His symptoms became so severe that he was unable to come to a standing position without experiencing syncope. Extensive workup was completed to identify an alternative cause of his dysautonomia with inconclusive results. Dysautonomia can have devastating consequences in regard to physical, social, and psychological health. Counseling individuals with poorly controlled diabetes about the importance of maintaining tight blood glucose control and avoiding COVID-19 infection should be primary interventions when treating patients with this DM1. Early detection and management of diabetes mellitus, COVID-19, and of possible resultant dysautonomia through medical interventions, as well as lifestyle changes, are extremely important measures to avoid development of dangerous and potentially life-threatening consequences.

Cardiac Autonomic Function in Long COVID-19 Using Heart Rate Variability: An Observational Cross-Sectional Study

BACKGROUND

Heart rate variability is a non-invasive, measurable, and established autonomic nervous system test. Long-term COVID-19 sequelae are unclear; however, acute symptoms have been studied.

OBJECTIVES

To determine autonomic cardiac differences between long COVID-19 patients and healthy controls and evaluate associations among symptoms, comorbidities, and laboratory findings.

METHODS

This single-center study included long COVID-19 patients and healthy controls. The heart rate variability (HRV), a quantitative marker of autonomic activity, was monitored for 24 h using an ambulatory electrocardiogram system. HRV indices were compared between case and control groups. Symptom frequency and inflammatory markers were evaluated. A significant statistical level of 5% (p-value 0.05) was adopted.

RESULTS

A total of 47 long COVID-19 patients were compared to 42 healthy controls. Patients averaged 43.8 (SD14.8) years old, and 60.3% were female. In total, 52.5% of patients had moderate illness. Post-exercise dyspnea was most common (71.6%), and 53.2% lacked comorbidities. CNP, D-dimer, and CRP levels were elevated (p-values of 0.0098, 0.0023, and 0.0015, respectively). The control group had greater SDNN24 and SDANNI (OR = 0.98 (0.97 to 0.99; p = 0.01)). Increased low-frequency (LF) indices in COVID-19 patients (OR = 1.002 (1.0001 to 1.004; p = 0.030)) and high-frequency (HF) indices in the control group (OR = 0.987 (0.98 to 0.995; p = 0.001)) were also associated.

CONCLUSIONS

Patients with long COVID-19 had lower HF values than healthy individuals. These variations are associated with increased parasympathetic activity, which may be related to long COVID-19 symptoms and inflammatory laboratory findings.

SARS-CoV-2 (COVID-19) as a possible risk factor for neurodevelopmental disorders

Pregnant women constitute one of the most vulnerable populations to be affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the cause of coronavirus disease 2019. SARS-CoV-2 infection during pregnancy could negatively impact fetal brain development via multiple mechanisms. Accumulating evidence indicates that mother to fetus transmission of SARS-CoV-2 does occur, albeit rarely. When it does occur, there is a potential for neuroinvasion via immune cells, retrograde axonal transport, and olfactory bulb and lymphatic pathways. In the absence of maternal to fetal transmission, there is still the potential for negative neurodevelopmental outcomes as a consequence of disrupted placental development and function leading to preeclampsia, preterm birth, and intrauterine growth restriction. In addition, maternal immune activation may lead to hypomyelination, microglial activation, white matter damage, and reduced neurogenesis in the developing fetus. Moreover, maternal immune activation can disrupt the maternal or fetal hypothalamic-pituitary-adrenal (HPA) axis leading to altered neurodevelopment. Finally, pro-inflammatory cytokines can potentially alter epigenetic processes within the developing brain. In this review, we address each of these potential mechanisms. We propose that SARS-CoV-2 could lead to neurodevelopmental disorders in a subset of pregnant women and that long-term studies are warranted.

The relationship between chronic immune response and neurodegenerative damage in long COVID-19

In the past two years, the world has faced the pandemic caused by the severe acute respiratory syndrome 2 coronavirus (SARS-CoV-2), which by August of 2022 has infected around 619 million people and caused the death of 6.55 million individuals globally. Although SARS-CoV-2 mainly affects the respiratory tract level, there are several reports, indicating that other organs such as the heart, kidney, pancreas, and brain can also be damaged. A characteristic observed in blood serum samples of patients suffering COVID-19 disease in moderate and severe stages, is a significant increase in proinflammatory cytokines such as interferon-α (IFN-α), interleukin-1β (IL-1β), interleukin-2 (IL-2), interleukin-6 (IL-6) and interleukin-18 (IL-18), as well as the presence of autoantibodies against interferon-α (IFN-α), interferon-λ (IFN-λ), C-C motif chemokine ligand 26 (CCL26), CXC motif chemokine ligand 12 (CXCL12), family with sequence similarity 19 (chemokine (C-C motif)-like) member A4 (FAM19A4), and C-C motif chemokine ligand 1 (CCL1). Interestingly, it has been described that the chronic cytokinemia is related to alterations of blood-brain barrier (BBB) permeability and induction of neurotoxicity. Furthermore, the generation of autoantibodies affects processes such as neurogenesis, neuronal repair, chemotaxis and the optimal microglia function. These observations support the notion that COVID-19 patients who survived the disease present neurological sequelae and neuropsychiatric disorders. The goal of this review is to explore the relationship between inflammatory and humoral immune markers and the major neurological damage manifested in post-COVID-19 patients.

Concomitant Guillain-Barré Syndrome and COVID-19: A Meta-Analysis of Cases

Background and Objectives: Recent findings demonstrate that the transmigration of severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) to the nervous system implicates severe neurotropic pathologies, including the onset of the rare disease called Guillain-Barré syndrome (GBS) which is characterized by immune-mediated polyneuropathy. This study aimed to identify the predisposing factors and the clinical features of coronavirus disease 2019 (COVID-19)-induced GBS. Materials and Methods: We have performed an analysis of 147 cases. A systematic review of the published research work was performed per the PRISMA statement to obtain individual participant data (IPD) for the meta-analysis. The search was conducted through PubMed, using the combined search terms "Guillain-Barré syndrome" and "COVID-19". All case reports and series in the English language with accessed full text were included in the search. Results: A systematic database search led to the retrieval of 112 peer-reviewed articles published between 1 April 2020, and 8 February 2022. The articles comprised 16 case series and 96 case reports containing IPD for 147 patients. Our findings showed that 77.6% of all cases were 40 years or older. Males comprised most of the cases (65.3%; n = 96). The intensive care unit (ICU) admission was 44.9%, and the need for mechanical ventilation (MV) was 38.1%. The patients presented with hyporeflexia or areflexia (84.4%; n = 124), lower limb strength and sensation impairment (93.2%; n = 138), upper limb strength and sensation impairment (85.7; n = 126), and somatic sensation impairment (72.8%; n = 107). The patients presented with increased cerebral spinal fluid (CSF) protein levels (92%; n = 92) and the presence of CSF albuminocytological dissociation (83.5%; n = 71). The most common variant of GBS observed was acute inflammatory demyelinating polyneuropathy (AIDP). We found that predisposing factors concomitant with COVID-19 and GBS were male gender and older age. Among the cases, patient mortality was 10.9%. Conclusions: A gap of knowledge exists regarding the complete spectrum of clinical characteristics of COVID-19-related GBS. Recent findings suggest that SARS-CoV-2 triggers GBS, as it follows a similar para-infectious pattern as the other viral agents contributing to the onset of GBS.

Citicoline and COVID-19: vis-à-vis conjectured

Coronavirus disease 2019 (COVID-19) is a current pandemic disease caused by a novel severe acute respiratory syndrome coronavirus virus respiratory type 2 (SARS-CoV-2). SARS-CoV-2 infection is linked with various neurological manifestations due to cytokine-induced disruption of the blood brain barrier (BBB), neuroinflammation, and peripheral neuronal injury, or due to direct SARS-CoV-2 neurotropism. Of note, many repurposed agents were included in different therapeutic protocols in the management of COVID-19. These agents did not produce an effective therapeutic eradication of SARS-CoV-2, and continuing searching for novel anti-SARS-CoV-2 agents is a type of challenge nowadays. Therefore, this study aimed to review the potential anti-inflammatory and antioxidant effects of citicoline in the management of COVID-19.

Molecular and cellular similarities in the brain of SARS-CoV-2 and Alzheimer's disease individuals

Infection with the etiological agent of COVID-19, SARS-CoV-2, appears capable of impacting cognition, which some patients with Post-acute Sequelae of SARS-CoV-2 (PASC). To evaluate neuro-pathophysiological consequences of SARS-CoV-2 infection, we examine transcriptional and cellular signatures in the Broadman area 9 (BA9) of the frontal cortex and the hippocampal formation (HF) in SARS-CoV-2, Alzheimer's disease (AD) and SARS-CoV-2 infected AD individuals, compared to age- and gender-matched neurological cases. Here we show similar alterations of neuroinflammation and blood-brain barrier integrity in SARS-CoV-2, AD, and SARS-CoV-2 infected AD individuals. Distribution of microglial changes reflected by the increase of Iba-1 reveal nodular morphological alterations in SARS-CoV-2 infected AD individuals. Similarly, HIF-1α is significantly upregulated in the context of SARS-CoV-2 infection in the same brain regions regardless of AD status. The finding may help to inform decision-making regarding therapeutic treatments in patients with neuro-PASC, especially those at increased risk of developing AD.

TEASER

SARS-CoV-2 and Alzheimer's disease share similar neuroinflammatory processes, which may help explain neuro-PASC.

Optic Perineuritis in an Asymptomatic SARS-CoV-2 Infection

INTRODUCTION

Optic perineuritis (OPN) is a previously undescribed sequela of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here we present a case of OPN that developed several weeks after initial confirmation of the presence of novel coronavirus RNA in the nasopharynx by polymerase chain reaction assay and subsequent confirmation of SARS-CoV-2 IgG seropositivity in the absence of other systemic inflammatory or infectious markers.

CASE REPORT

An asymptomatic 71-year-old man with noninsulin-dependent diabetes mellitus (NIDDM) tested RNA positive for SARS-CoV-2 during a routine screening of patients at a skilled nursing facility. ~3 weeks after the positive SARS-CoV-2 polymerase chain reaction test, the patient developed subacute ophthalmoparesis of the left eye, horizontal diplopia, retro-orbital pain, and frontal headache. An urgent magnetic resonance imaging of the head and orbits suggested OPN. Cerebrospinal fluid studies were without evidence of other infectious, inflammatory, neoplastic, or paraneoplastic processes. He was started on a 5-day course of high-dose intravenous steroids and later transitioned to oral steroid therapy. Sixteen days after the initiation of steroid therapy, the patient had no headache or retro-orbital pain and demonstrated a marked improvement in horizontal gaze.

CONCLUSION

SARS-CoV-2-associated neurological sequelae have been increasingly recognized during the current coronavirus disease 2019 pandemic. The present case suggests that patients with confirmed SARS-CoV-2 positivity, even without pulmonary or other classic manifestations of active infection, may manifest diverse clinical presentations including postinfectious OPN that could be related to an underlying autoimmune reactive inflammatory response.

Central hypersomnia and chronic insomnia: expanding the spectrum of sleep disorders in long COVID syndrome - a prospective cohort study

Introduction

Long-onset COVID syndrome has been described in patients with COVID-19 infection with persistence of symptoms or development of sequelae beyond 4 weeks after the onset of acute symptoms, a medium- and long-term consequence of COVID-19. This syndrome can affect up to 32% of affected individuals, with symptoms of fatigue, dyspnea, chest pain, cognitive disorders, insomnia, and psychiatric disorders. The present study aimed to characterize and evaluate the prevalence of sleep symptoms in patients with long COVID syndrome.

Methodology

A total of 207 patients with post-COVID symptoms were evaluated through clinical evaluation with a neurologist and specific exams in the subgroup complaining of excessive sleepiness.

Results

Among 189 patients included in the long COVID sample, 48 (25.3%) had sleep-related symptoms. Insomnia was reported by 42 patients (22.2%), and excessive sleepiness (ES) was reported by 6 patients (3.17%). Four patients with ES were evaluated with polysomnography and test, multiple sleep latencies test, and actigraphic data. Two patients had a diagnosis of central hypersomnia, and one had narcolepsy. A history of steroid use was related to sleep complaints (insomnia and excessive sleepiness), whereas depression was related to excessive sleepiness. We observed a high prevalence of cognitive complaints in these patients.

Conclusion

Complaints related to sleep, such as insomnia and excessive sleepiness, seem to be part of the clinical post-acute syndrome (long COVID syndrome), composing part of its clinical spectrum, relating to some clinical data.

SARS-CoV-2 mediated neurological disorders in COVID-19: Measuring the pathophysiology and immune response

The emergence of beta-coronavirus SARS-CoV-2 gets entry into its host cells by recognizing angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRESS2) receptors, which are responsible for coronavirus diseases-2019 (COVID-19). Global communities have been affected by COVID-19, especially caused the neurological complications and other critical medical issues. COVID-19 associated complications appear in aged people with underlying neurological states, especially in Parkinson's disease (PD) and Alzheimer's disease (AD). ACE2 receptors abundantly expressed in dopamine neurons may worsen the motor symptoms in PD and upregulates in SARS-CoV-2 infected aged patients' brain with AD. Immune-mediated cytokines released in SARS-CoV-2 infection lead to an indirect immune response that damages the central nervous system. Extreme cytokines release (cytokine storm) occurs due to aberrant immune pathways, and activation in microglial propagates CNS damage in COVID-19 patients. Here, we have explored the pathophysiology, immune responses, and long-term neurological impact on PD and AD patients with COVID-19. It is also a crucial step to understanding COVID-19 pathogenesis to reduce fatal outcomes of neurodegenerative diseases.

Pathophysiology of Post-COVID syndromes: a new perspective

Most COVID-19 patients recovered with low mortality; however, some patients experienced long-term symptoms described as "long-COVID" or "Post-COVID syndrome" (PCS). Patients may have persisting symptoms for weeks after acute SARS-CoV-2 infection, including dyspnea, fatigue, myalgia, insomnia, cognitive and olfactory disorders. These symptoms may last for months in some patients. PCS may progress in association with the development of mast cell activation syndrome (MCAS), which is a distinct kind of mast cell activation disorder, characterized by hyper-activation of mast cells with inappropriate and excessive release of chemical mediators. COVID-19 survivors, mainly women, and patients with persistent severe fatigue for 10 weeks after recovery with a history of neuropsychiatric disorders are more prone to develop PCS. High D-dimer levels and blood urea nitrogen were observed to be risk factors associated with pulmonary dysfunction in COVID-19 survivors 3 months post-hospital discharge with the development of PCS. PCS has systemic manifestations that resolve with time with no further complications. However, the final outcomes of PCS are chiefly unknown. Persistence of inflammatory reactions, autoimmune mimicry, and reactivation of pathogens together with host microbiome alterations may contribute to the development of PCS. The deregulated release of inflammatory mediators in MCAS produces extraordinary symptoms in patients with PCS. The development of MCAS during the course of SARS-CoV-2 infection is correlated to COVID-19 severity and the development of PCS. Therefore, MCAS is treated by antihistamines, inhibition of synthesis of mediators, inhibition of mediator release, and inhibition of degranulation of mast cells.

Post-COVID Headache: A Literature Review

Purpose of Review

Post-COVID headache may be unique in presentation and mechanism, often presenting as a new phenotype in patients with a history of a primary headache disorder or resulting in a new headache syndrome in those without history of headache. This review presents a description of the literature published focused on post-COVID headache. Additionally, we discuss potential mechanisms and considerations for treatment of post-COVID headache.

Recent Findings

Headache is one of the most common symptoms of COVID. Common characteristics are revealed when reviewing the phenotypes of headaches that have been described in patients with COVID-19, with most headache phenotypes resembling migraine and new persistent daily headache. Post-COVID headaches are often described as moderate to severe, persistent, and treatment refractory.

Summary

This review highlights the diversity of presentation of headaches that present as a complication of COVID-19. Treatment of post-COVID headache is challenging, especially in the setting of a pandemic where resources are limited.

Clinical Case

A 42-year-old woman with a history of episodic migraine without aura presents over video visit with a new headache type. Her typical headaches are predominantly left sided, throbbing in nature, and associated with photophobia and phonophobia. They are fully relieved by oral sumatriptan 2 h after treatment. She describes this new headache as a constant, pulsating, holocephalic pain with no other migrainous features that have been ongoing for 6 weeks. She notes that the headache has been persistent since that time. She has tried over-the-counter acetaminophen and ibuprofen and her typical migraine abortive therapy without relief. She is debilitated and wonders if there is anything that will take the pain away. She shares that she tested positive for COVID-19 about 2 days prior to headache onset and has associated rhinorrhea, anosmia, and ageusia.

Exploring the Paradox of COVID-19 in Neurological Complications with Emphasis on Parkinson’s and Alzheimer’s Disease

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a human coronavirus (HCoV) that has created a pandemic situation worldwide as COVID-19. This virus can invade human cells via angiotensin-converting enzyme 2 (ACE2) receptor-based mechanisms, affecting the human respiratory tract. However, several reports of neurological symptoms suggest a neuroinvasive development of coronavirus. SARS-CoV-2 can damage the brain via several routes, along with direct neural cell infection with the coronavirus. The chronic inflammatory reactions surge the brain with proinflammatory elements, damaging the neural cells, causing brain ischemia associated with other health issues. SARS-CoV-2 exhibited neuropsychiatric and neurological manifestations, including cognitive impairment, depression, dizziness, delirium, and disturbed sleep. These symptoms show nervous tissue damage that enhances the occurrence of neurodegenerative disorders and aids dementia. SARS-CoV-2 has been seen in brain necropsy and isolated from the cerebrospinal fluid of COVID-19 patients. The associated inflammatory reaction in some COVID-19 patients has increased proinflammatory cytokines, which have been investigated as a prognostic factor. Therefore, the immunogenic changes observed in Parkinson's and Alzheimer's patients include their pathogenetic role. Inflammatory events have been an important pathophysiological feature of neurodegenerative diseases (NDs) such as Parkinson's and Alzheimer's. The neuroinflammation observed in AD has exacerbated the Aβ burden and tau hyperphosphorylation. The resident microglia and other immune cells are responsible for the enhanced burden of Aβ and subsequently mediate tau phosphorylation and ultimately disease progression. Similarly, neuroinflammation also plays a key role in the progression of PD. Several studies have demonstrated an interplay between neuroinflammation and pathogenic mechanisms of PD. The dynamic proinflammation stage guides the accumulation of α-synuclein and neurodegenerative progression. Besides, few viruses may have a role as stimulators and generate a cross-autoimmune response for α-synuclein. Hence, neurological complications in patients suffering from COVID-19 cannot be ruled out. In this review article, our primary focus is on discussing the neuroinvasive effect of the SARS-CoV-2 virus, its impact on the blood-brain barrier, and ultimately its impact on the people affected with neurodegenerative disorders such as Parkinson's and Alzheimer's.

Olfactory impairment in psychiatric disorders: Does nasal inflammation impact disease psychophysiology?

Olfactory impairments contribute to the psychopathology of mental illnesses such as schizophrenia and depression. Recent neuroscience research has shed light on the previously underappreciated olfactory neural circuits involved in regulation of higher brain functions. Although environmental factors such as air pollutants and respiratory viral infections are known to contribute to the risk for psychiatric disorders, the role of nasal inflammation in neurobehavioral outcomes and disease pathophysiology remains poorly understood. Here, we will first provide an overview of published findings on the impact of nasal inflammation in the olfactory system. We will then summarize clinical studies on olfactory impairments in schizophrenia and depression, followed by preclinical evidence on the neurobehavioral outcomes produced by olfactory dysfunction. Lastly, we will discuss the potential impact of nasal inflammation on brain development and function, as well as how we can address the role of nasal inflammation in the pathophysiological mechanisms underlying psychiatric disorders. Considering the current outbreak of Coronavirus Disease 2019 (COVID-19), which often causes nasal inflammation and serious adverse effects for olfactory function that might result in long-lasting neuropsychiatric sequelae, this line of research is particularly critical to understanding of the potential significance of nasal inflammation in the pathophysiology of psychiatric disorders.

Acute Disseminated Encephalomyelitis with Prefrontal Cortex Involvement in a 9-Year-Old Child after COVID-19 Infection: A Case Report

The aim of the study was to present the rare co-occurring radiological findings of a child presenting with acute disseminated encephalomyelitis (ADEM) with a spinal cord and prefrontal cortex involvement after coronavirus disease 2019 (COVID-19) illness. The patient, who had COVID-19 a few weeks earlier, presented with progressive weakness in the right upper and lower extremities. Neurological examination of the patient was performed, and cranial magnetic resonance imaging (MRI) was taken on the same day. Serum severe acute respiratory syndrome coronavirus immunoglobulin M antibody testing was positive. MRI of the brain parenchyma and thoracic spine revealed fluid-attenuated inversion recovery and T2-weighted hyperintense lesions. Additionally, mild contrast enhancement was observed in both the prefrontal cortexes. The patient was discharged 10 days later with complete clinical recovery. Unlike other post-COVID-19 ADEM cases presenting in the literature, prefrontal cortex involvement makes our case rare.

An overview of the neurological aspects in COVID-19 infection

The Crown-shaped, severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) triggered the globally fatal illness of Coronavirus disease-2019 (COVID-19). This infection is known to be initially reported in bats and has been causing major respiratory challenges. The primary symptoms of COVID-19 include fever, fatigue and dry cough. As progressed the complications may lead to acute respiratory distress syndrome (ADRS), arrhythmia and shock. This review illustrates the neurological and neuropsychiatric impairments due to COVID-19 infection. The SARS-CoV-2 virus enters via the hematogenous or neural route, spreads to the Central Nervous System (CNS), causing a blood-brain barrier (BBB) dysfunction. Recent scientific articles have reported that SARS-CoV-2 causes several neurological issues such as encephalitis, seizures, acute stroke, delirium, meningoencephalitis and Guillain-Barré Syndrome (GBS). As a long-term effect of this disease certain neuropsychiatric conditions are witnessed such as depression and anxiety. Invasion into followed by degeneration takes place causing an uncontrolled immune response. Transcription factors like NF-κB (nuclear factor kappa light chain enhancer of activated B cells), which modulate genes responsible for inflammatory response gets over expressed. Nrf2 (nuclear factor erythroid 2- related factor 2) counterpoises the inflammation by antioxidant response towards COVID-19 infection. Like every other infection, the severity of this infection leads to deterioration of major organ systems and even leads to death. By the columns of this review, we elaborate on the neurological aspects of this life-threatening infection.

COVID-19 Worsens Chronic Lumbosacral Radicular Pain—Case Series Report

The knowledge of the COVID-19 symptomatology has increased since the beginning of the SARS-CoV-2 pandemic. The symptoms of nervous system involvement have been observed across the spectrum of COVID-19 severity. Reports describing difficulties of nerve roots are rare; the affection of brain and spinal cord by SARS-CoV-2 is of leading interest. Our aim therefore is to describe the radicular pain deterioration in the group of nine chronic lumbosacral radicular syndrome sufferers in acute COVID-19. The intensity of radicular pain was evaluated by the Visual Analogue Scale (VAS). The VAS score in acute infection increased from 5.6 ± 1.1 to 8.0 ± 1.3 (Cohen’s d = 1.99) over the course of COVID-19, indicating dramatic aggravation of pain intensity. However, the VAS score decreased spontaneously to pre-infection levels after 4 weeks of COVID-19 recovery (5.8 ± 1.1). The acute SARS-CoV-2 infection worsened the pre-existing neural root irritation symptomatology, which may be ascribed to SARS-CoV-2 radiculitis of neural roots already compressed by the previous disc herniation. These findings based on clinical observations indicate that the neurotropism of novel coronavirus infection can play an important role in the neural root irritation symptomatology deterioration in patients with chronic pre-existing lumbosacral radicular syndrome.

COVID-19 and Neurodegenerative Diseases: Prion-Like Spread and Long-Term Consequences

COVID-19 emerged as a global pandemic starting from Wuhan in China and spread at a lightning speed to the rest of the world. One of the potential long-term outcomes that we speculate is the development of neurodegenerative diseases as a long-term consequence of SARS-CoV-2 especially in people that have developed severe neurological symptoms. Severe inflammatory reactions and aging are two very strong common links between neurodegenerative diseases and COVID-19. Thus, patients that have very high viral load may be at high risk of developing long-term adverse neurological consequences such as dementia. We hypothesize that people with neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and aged people are at higher risk of getting the COVID-19 than normal adults. The basis of this hypothesis is the fact that SARS-CoV-2 uses as a receptor angiotensin-converting enzyme 2 to enter the host cell and that this interaction is calcium-dependent. This could then suggest a direct relationship between neurodegenerative diseases, ACE-2 expression, and the susceptibility to COVID-19. The analysis of the available literature showed that COVID-19 virus is neurotropic and was found in the brains of patients infected with this virus. Furthermore, that the risk of having the infection increases with dementia and that infected people with severe symptoms could develop dementia as a long-term consequence. Dementia could be developed following the acceleration of the spread of prion-like proteins. In the present review we discuss current reports concerning the prevalence of COVID-19 in dementia patients, the individuals that are at high risk of suffering from dementia and the potential acceleration of prion-like proteins spread following SARS-CoV-2 infection.

SARS-CoV-2 Infection and Possible Neonatal Neurological Outcomes: A Literature Review

The virus responsible for COVID-19 is designated "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2), a highly transmissible and pathogenic coronavirus. Although people of all ages are susceptible to SARS-CoV-2 infection, clinical manifestations may vary with age. The response of neonates to SARS-CoV-2 infection or exposure differs from that of children and adults. Encephalitis due to viral infections in the central nervous system (CNS) and childhood multisystem inflammatory syndrome (MIS-C) are some of the possible neonatal consequences of SARS-CoV-2 infection. This review aims to verify possible neonatal neurological outcomes after SARS-CoV-2 infection. Overall, the cellular and molecular basis of the neurological sequelae of SARS-CoV-2 in neonates remains unclear, and attempts to elucidate the pathophysiology of COVID-19 involve a comparison with the mechanism of other viral diseases. There are a considerable number of case reports in the literature exploring neurological outcomes in the neonatal period. In this review, we present possible effects of SARS-CoV-2 in neonates, emphasizing the importance of monitoring this group. The mechanisms of SARS-CoV-2 entry into the CNS have not yet been fully elucidated, and the potential severity of SARS-CoV-2 infection in neonates, as well as the possible short- and long-term neurological sequelae, remain unclear.

Selective COVID-19 Coinfections in Diabetic Patients with Concomitant Cardiovascular Comorbidities Are Associated with Increased Mortality

Coinfections and comorbidities add additional layers of difficulties into the challenges of COVID-19 patient management strategies. However, studies examining these clinical conditions are limited. We have independently investigated the significance of associations of specific bacterial species and different comorbidities in the outcome and case fatality rates among 129 hospitalized comorbid COVID-19 patients. For the first time, to best of our knowledge, we report on the predominance of Klebsiella pneumoniae and Acinetobacter baumannii in COVID-19 non-survival diabetic patients The two species were significantly associated to COVID-19 case fatality rates (p-value = 0.02186). Coinfection rates of Klebsiella pneumoniae and Acinetobacter baumannii in non-survivors were 93% and 73%, respectively. Based on standard definitions for antimicrobial resistance, Klebsiella pneumoniae and Acinetobacter baumannii were classified as multidrug resistant and extremely drug resistant, respectively. All patients died at ICU with similar clinical characterisitics. Of the 28 major coinfections, 24 (85.7%) were in non-survivor diabetic patients, implying aggravating and worsening the course of COVID-19. The rates of other comorbidities varied: asthma (47%), hypertension (79.4%), ischemic heart disease (71%), chronic kidney disease (35%), and chronic liver disease (32%); however, the rates were higher in K. pneumoniae and were all concomitantly associated to diabetes. Other bacterial species and comorbidities did not have significant correlation to the outcomes. These findings have highly significant clinical implications in the treatment strategies of COVID-19 patients. Future vertical genomic studies would reveal more insights into the molecular and immunological mechanisms of these frequent bacterial species. Future large cohort multicenter studies would reveal more insights into the mechanisms of infection in COVID-19.

An overview of post COVID sequelae

After healing from COVID-19, patients often experience a slew of symptoms known as post COVID-19 sequelae. Despite the fact that the SARS-CoV-2 pandemic is still ongoing, post-Covid-19 syndrome is already a difficult problem to address: long-term multiorgan sequelae, while frequently described, have yet to be systematized. As a result, post-Covid-19 syndrome can have a major influence on surviving patients' working capacity as well as their personal lives. The clinical spectrum and long-term course of this clinical entity must be better understood. Post-Covid syndrome affects a wide spectrum of individuals (16-87%), with pneumological and cognitive symptoms being the most common. Pulmonary fibrosis was the most common organic consequence seen in post-Covid patients. In conclusion, post-Covid-19 syndrome can have a major impact on the health of survivors. Working-age patients should seek rehabilitation and follow-up in interdisciplinary rehabilitation programmes. Given the pandemic's global extent, it's obvious that COVID-19-related healthcare demands will continue to climb for the foreseeable future. For COVID-19 survivors' long-term mental and physical health, present outpatient infrastructure will be utilised, scalable healthcare models will be built, and cross-disciplinary collaboration will be required.

COVID-19: Cellular and Molecular Mechanisms of Brain Damage

The most common clinical manifestation of COVID-19 is bilateral pneumonia, a diffuse, alveolar injury with severe microangiopathy. Systemic infection is accompanied by an increase in circulating chemokines and interleukins in the blood, which penetrate the blood–brain barrier (BBB) and enter the brain. Clinical materials indicate lesions of the brain and peripheral nervous system, as well as neurodegenerative and mental disorders. Due to violations of the cerebral endothelium system and changes in the balance of ACE2-coupled cytochemical processes, coagulopathy develops, leading to microthrombosis and vascular occlusion. The concept of SARS-CoV-2 “neurotropism” is discussed as a rationale for the penetration by the virus into the brain. Infection can occur as axonal transport through the bulbar zone and the olfactory area of the cerebral cortex. Even more common is the “hematogenous pathway” of viral transfection, which includes damage to the vascular endothelium and a violation of the protective role of the BBB. Another concept that explains the mechanism of brain damage relates to the phenomenon of neuroinflammation. Astrocytes and microglia are considered potential targets of the SARS-CoV-2 coronavirus. The dissonance of the biochemical processes of the axis ACE2/ACE and changes in the functions of angiotensin peptides leads to the activation of astroglia with the development of neurodestructive processes in COVID-19.

SARS-CoV-2 interacts with renin-angiotensin system: impact on the central nervous system in elderly patients

SARS-CoV-2 is a recently identified coronavirus that causes the current pandemic disease known as COVID-19. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as a receptor, suggesting that the initial steps of SARS-CoV-2 infection may have an impact on the renin-angiotensin system (RAS). Several processes are influenced by RAS in the brain. The neurological symptoms observed in COVID-19 patients, including reduced olfaction, meningitis, ischemic stroke, cerebral thrombosis, and delirium, could be associated with RAS imbalance. In this review, we focus on the potential role of disturbances in the RAS as a cause for central nervous system sequelae of SARS-CoV-2 infection in elderly patients.

Vascular Dysfunction of COVID-19 Is Partially Reverted in the Long-Term

Background:

COVID-19 is characterized by severe inflammation during the acute phase and increased aortic stiffness in the early postacute phase. In other models, aortic stiffness is improved after the reduction of inflammation. We aimed to evaluate the mid- and long-term effects of COVID-19 on vascular and cardiac autonomic function. The primary outcome was aortic pulse wave velocity (aPWV).

Methods:

The cross-sectional Study-1 included 90 individuals with a history of COVID-19 and 180 matched controls. The longitudinal Study-2 included 41 patients with COVID-19 randomly selected from Study-1 who were followed-up for 27 weeks.

Results:

Study-1: Compared with controls, patients with COVID-19 had higher aPWV and brachial PWV 12 to 24 (but not 25–48) weeks after COVID-19 onset, and they had higher carotid Young’s elastic modulus and lower distensibility 12 to 48 weeks after COVID-19 onset. In partial least squares structural equation modeling, the higher the hs-CRP (high-sensitivity C-reactive protein) at hospitalization was, the higher the aPWV 12 to 48 weeks from COVID-19 onset (path coefficient: 0.184; P =0.04). Moreover, aPWV (path coefficient: −0.186; P =0.003) decreased with time. Study-2: mean blood pressure and carotid intima-media thickness were comparable at the end of follow-up, whereas aPWV (−9%; P =0.01), incremental Young’s elastic modulus (−17%; P =0.03), baroreflex sensitivity (+28%; P =0.049), heart rate variability triangular index (+15%; P =0.01), and subendocardial viability ratio (+12%; P =0.01×10 −4 ) were significantly improved. There was a trend toward improvement in brachial PWV (−6%; P =0.14) and carotid distensibility (+18%; P =0.05). Finally, at the end of follow-up (48 weeks after the onset of COVID-19) aPWV (+6%; P =0.04) remained significantly higher in patients with COVID-19 than in control subjects.

Conclusions:

COVID-19-related arterial stiffening involves several arterial tree portions and is partially resolved in the long-term.

Epitope-based peptide vaccine design and elucidation of novel compounds against 3C like protein of SARS-CoV-2

Coronaviruses (CoVs) are positive-stranded RNA viruses with short clubs on their edges. CoVs are pathogenic viruses that infect several animals and plant organisms, as well as humans (lethal respiratory dysfunctions). A noval strain of CoV has been reported and named as SARS-CoV-2. Numerous COVID-19 cases were being reported all over the World. COVID-19 and has a high mortality rate. In the present study, immunoinformatics techniques were utilized to predict the antigenic epitopes against 3C like protein. B-cell epitopes and Cytotoxic T-lymphocyte (CTL) were designed computationally against SARS-CoV-2. Multiple Sequence Alignment (MSA) of seven complete strains (HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV, MERS-CoV, and SARS-CoV-2) was performed to elucidate the binding domain and interacting residues. MHC-I binding epitopes were evaluated by analyzing the binding affinity of the top-ranked peptides having HLA molecule. By utilizing the docked complexes of CTL epitopes with antigenic sites, the binding relationship and affinity of top-ranked predicted peptides with the MHC-I HLA protein were investigated. The molecular docking analyses were conducted on the ZINC database library and twelve compounds having least binding energy were scrutinized. In conclusion, twelve CTL epitopes (GTDLEGNFY, TVNVLAWLY, GSVGFNIDY, SEDMLNPNY, LSQTGIAV, VLDMCASLK, LTQDHVDIL, TTLNDFNLV, CTSEDMLNP, TTITVNVLA, YNGSPSGVY, and SMQNCVLKL) were identified against SARS-CoV-2.

Coronaviruses and their relationship with multiple sclerosis: is the prevalence of multiple sclerosis going to increase after the Covid-19 pandemia?

The purpose of this review is to examine whether there is a possible (etiological/triggering) relationship between infection with various Coronaviruses, including Severe Acute Respiratory Syndrome-related Coronavirus-2 (SARS-CoV-2), the virus responsible for the Coronavirus disease-19 (Covid-19) pandemia, and Multiple Sclerosis (MS), and whether an increase of the prevalence of MS after the current Covid-19 pandemia should be expected, examining new and preexisting data. Although the exact pathogenesis of MS remains unknown, environmental agents seem to greatly influence the onset of the disease, with viruses being the most popular candidate. Existing data support this possible etiological relationship between viruses and MS, and experimental studies show that Coronaviruses can actually induce an MS-like demyelinating disease in animal models. Findings in MS patients could also be compatible with this coronaviral MS hypothesis. More importantly, current data from the Covid-19 pandemia show that SARS-CoV-2 can trigger autoimmunity and possibly induce autoimmune diseases, in the Central Nervous System as well, strengthening the viral hypothesis of MS. If we accept that Coronaviruses can induce MS, it is reasonable to expect an increase in the prevalence of MS after the Covid-19 pandemia. This knowledge is of great importance in order to protect the aging groups that are more vulnerable against autoimmune diseases and MS specifically, and to establish proper vaccination and health policies.

Coronavirus Disease 2019, Eye Pain, Headache, and Beyond

BACKGROUND

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which causes Coronavirus Disease 2019 (COVID-19), emerged in December 2019 and became a devastating pandemic. Although its respiratory effects can be deadly and debilitating, it can lead to other systemic disorders, such as those causing eye pain and headache. This literature review aims to describe presentations of eye pain and headache in relation to COVID-19, with an emphasis on how these disorders help us to understand the pathophysiology of COVID-19.

EVIDENCE ACQUISITION

Literature was mined from the PubMed database using the key terms: "eye pain," "conjunctivitis," "episcleritis," "optic neuritis," "migraine," and "headache" in conjunction with "COVID-19" and "SARS-CoV-2." With the exception of general background pathology, articles that predated 2006 were excluded. Case reports, literature reviews, and meta-analyses were all included. Where SARS-CoV-2 research was deficient, pathology of other known viruses was considered. Reports of ocular manifestations of vision loss in the absence of eye pain were excluded. The primary search was conducted in June 2021.

RESULTS

The literature search led to a focused review of COVID-19 associated with conjunctivitis, episcleritis, scleritis, optic neuritis, and myelin oligodendrocyte glycoprotein-associated optic neuritis. Four distinct COVID-19-related headache phenotypes were identified and discussed.

CONCLUSIONS

Eye pain in the setting of COVID-19 presents as conjunctivitis, episcleritis, scleritis, or optic neuritis. These presentations add to a more complete picture of SARS-CoV-2 viral transmission and mechanism of host infection. Furthermore, eye pain during COVID-19 may provide evidence of hypersensitivity-type reactions, neurovirulence, and incitement of either novel or subclinical autoimmune processes. In addition, investigation of headaches associated with COVID-19 demonstrated 4 distinct phenotypes that follow third edition of the International Classification of Headache Disorders categories: headaches associated with personal protective equipment, migraine, tension-type headaches, and COVID-19-specific headache. Early identification of headache class could assist in predicting the clinical course of disease. Finally, investigation into the COVID-19-associated headache phenotype of those with a history of migraine may have broader implications, adding to a more general understanding of migraine pathology.

Neurological Associations of SARS-CoV-2 Infection: A Systematic Review

BACKGROUND

The current ongoing COVID-19 pandemic has compelled us to scrutinize major outbreaks in the past two decades, Severe Acute Respiratory Syndrome (SARS), in 2002, and Middle East Respiratory Syndrome (MERS), in 2012. We aimed to assess the associated neurological manifestations with SARS CoV-2 infection.

METHODS

In this systematic review, a search was carried out by key-electronic databases, controlled vocabulary, and indexing of trials to evaluate the available pertinent studies which included both medical subject headings (MeSH) and advanced electronic databases comprising PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL). Peer-reviewed studies published in English and Spanish were considered, which reported data on the neurological associations of individuals with suspected or laboratory-confirmed SARS-CoV-2 infection. Outcomes were nervous signs or symptoms, symptom severity, and diagnoses.

RESULTS

Our search identified 45 relevant studies, with 21 case reports, 3 case series, 9 observational studies, 1 retrospective study, 9 retrospective reviews, and 2 prospective reviews. This systematic review revealed that most commonly reported neuronal presentations involved headache, nausea, vomiting and muscular symptoms like fibromyalgia. Anosmia and ageusia, defects in clarity or sharpness of vision (error in visual acuity), and pain may occur in parallel. Notable afflictions in the form of anxiety, anger, confusion, post-traumatic stress symptoms, and post-intensive care syndrome were observed in individuals who were kept in quarantine and those with long-stay admissions in healthcare settings. SARS CoV-2 infection may result in cognitive impairment. Patients with more severe infection exhibited uncommon manifestations, such as acute cerebrovascular diseases (intracerebral haemorrhage, stroke), rhabdomyolysis, encephalopathy, and Guillain-Barré syndrome.

CONCLUSION

SARS-CoV-2 patients experience neuronal presentations varying with the progression of the infection. Healthcare professionals should be acquainted with the divergent neurological symptoms to curb misdiagnosis and limit long-term sequelae. Health-care planners and policymakers must prepare for this eventuality, while the ongoing studies increase our knowledge base on acute and chronic neurological associations of this pathogen.

Neurological manifestations and pathogenic mechanisms of COVID-19

Coronavirus disease (COVID-19) arising from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral infection has caused a worldwide pandemic, mainly owing to its highly virulent nature stemming from a very strong and highly efficacious binding to the angiotensin converting enzyme-2 (ACE2) receptor. As the pandemic developed, increasing numbers of COVID-19 patients with neurological manifestations were reported, strongly suggesting a causal relationship. Indeed, direct invasion of SARS-CoV-2 viral particles into the brain can occur through the cribriform plate via olfactory nerves, passage through a damaged blood-brain-barrier, or via haematogenic infiltration of infected leukocytes. Neurological complications range from potentially fatal encephalopathy and stroke, to the onset of headaches and dizziness, which despite their apparent innocuous presentation may still imply a more sinister pathology. Here, we summarize the most recent knowledge on the neurological presentations typically being associated with COVID-19, whilst providing potential pathophysiological mechanisms. The latter are centered upon hypoxic brain injury, generation of a cytokine storm with attendant immune-mediated damage, and a prothrombotic state. A better understanding of both the neuroinvasive properties of SARS-CoV-2 and the neurological complications of COVID-19 will be important to improve patient outcomes.