Cross-Talk Between Key Players in Patients with COVID-19 and Ischemic Stroke: A Review on Neurobiological Insight of the Pandemic

The Role of ACE2 in Neurological Disorders: From Underlying Mechanisms to the Neurological Impact of COVID-19

Angiotensin-converting enzyme 2 (ACE2) has become a hot topic in neuroscience research in recent years, especially in the context of the global COVID-19 pandemic, where its role in neurological diseases has received widespread attention. ACE2, as a multifunctional metalloprotease, not only plays a critical role in the cardiovascular system but also plays an important role in the protection, development, and inflammation regulation of the nervous system. The COVID-19 pandemic further highlights the importance of ACE2 in the nervous system. SARS-CoV-2 enters host cells by binding to ACE2, which may directly or indirectly affect the nervous system, leading to a range of neurological symptoms. This review aims to explore the function of ACE2 in the nervous system as well as its potential impact and therapeutic potential in various neurological diseases, providing a new perspective for the treatment of neurological disorders.

Brain Arteriovenous Malformation Hemorrhage and Pituitary Adenoma in a COVID-19-Positive Patient

Brain arteriovenous malformations (AVMs) are usually asymptomatic. They can cause intense pain or bleeding or lead to other serious medical problems. We present a rare case of a woman who presented with a severe headache and was brought to the emergency service for an intracerebral hemorrhage due to a ruptured AVM. During the surgery, a sellar mass was identified that was also resected. AVM showed vasculitis, endarteritis, endothelial damage, leukocyte plug, and damage to the vessel wall with fragmentation of the collagen and actin filaments. The sellar mass showed a non-functioning pituitary adenoma with hemorrhagic foci and necrosis as well as a proteinaceous vs. lipid material deposition with minimal vascular changes such as endothelial hyperplasia with minimal vasculitis and hyperplasia of reticular stellate cells, with positive glial fibrillary acidic protein (GFAP), which expressed low expression of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), IL6, IL10, IL17, tumor necrosis factor-alpha (TNFa), HIF1a, factor VIII (FVIII), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and VEGF receptor 2 (VEGFR2). The patient's polymerase chain reaction COVID-19 test was positive, and she died three days after the surgery procedure. In our knowledge of COVID-19 brain lesions and in the literature review, this was a rare case of a double pathology associated with COVID-19 infection characterized by rupture of the AVM with hemorrhages and brain infarcts associated with endarteritis, vessel wall injuries, and pituitary apoplexy.

Factors associated with SARS-CoV-2 vaccine hesitancy after stroke: a cross-sectional study

BACKGROUND

The vaccination status of post-stroke patients, who are at high risk of severe outcomes from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is a significant concern, yet it remains unclear. We aimed to explore the vaccination status, factors associated with vaccine hesitancy, and adverse effects after vaccination among post-stroke patients.

METHODS

This multi-center observational study enrolled hospitalized post-stroke patients from six Chinese hospitals (Oct 1, 2020 - Mar 31, 2021), examining vaccine uptake and self-reported reasons for vaccine hesitancy, utilizing logistic regression to investigate risk factors for vaccine hesitancy, and recording any adverse reactions post-vaccination.

RESULTS

Of the total 710 post-stroke patients included in the study, 430 (60.6%) had completed the recommended full-3 dose SARS-CoV-2 vaccination, with 176 (24.8%) remaining unvaccinated. The most common reasons for vaccine hesitancy were concerns about vaccine side effects (41.5%) and impaired mobility (33.9%). Logistic regression identified advanced age (aOR = 1.97, 95%CI: 1.36-2.85, P = 0.001), lower Barthel Index score (aOR = 0.88, 95%CI: 0.82-0.93, P = 0.018), higher Modified Rankin Scale score (aOR = 1.85, 95%CI: 1.32-2.56, P = 0.004), and poorer usual activity level of EuroQol 5-Dimension (aOR = 2.82, 95%CI: 1.51-5.28, P = 0.001) as independent risk factors for vaccine hesitancy. Approximately 14.8% reported minor adverse reactions, mainly pain at the injection site.

CONCLUSION

We found that post-stroke patients have insufficient SARS-CoV-2 vaccination rates, with key risk factors for vaccine hesitancy including concerns about side effects, advanced age, and functional impairments. No severe adverse reactions were observed among the vaccinated population.

Role of the renin-angiotensin system in the development of COVID-19-associated neurological manifestations

SARS-CoV-2 causes COVID-19, which has claimed millions of lives. This virus can infect various cells and tissues, including the brain, for which numerous neurological symptoms have been reported, ranging from mild and non-life-threatening (e.g., headaches, anosmia, dysgeusia, and disorientation) to severe and life-threatening symptoms (e.g., meningitis, ischemic stroke, and cerebral thrombosis). The cellular receptor for SARS-CoV-2 is angiotensin-converting enzyme 2 (ACE2), an enzyme that belongs to the renin-angiotensin system (RAS). RAS is an endocrine system that has been classically associated with regulating blood pressure and fluid and electrolyte balance; however, it is also involved in promoting inflammation, proliferation, fibrogenesis, and lipogenesis. Two pathways constitute the RAS with counter-balancing effects, which is the key to its regulation. The first axis (classical) is composed of angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and angiotensin type 1 receptor (AT1R) as the main effector, which -when activated- increases the production of aldosterone and antidiuretic hormone, sympathetic nervous system tone, blood pressure, vasoconstriction, fibrosis, inflammation, and reactive oxygen species (ROS) production. Both systemic and local classical RAS' within the brain are associated with cognitive impairment, cell death, and inflammation. The second axis (non-classical or alternative) includes ACE2, which converts Ang II to Ang-(1-7), a peptide molecule that activates Mas receptor (MasR) in charge of opposing Ang II/AT1R actions. Thus, the alternative RAS axis enhances cognition, synaptic remodeling, cell survival, cell signal transmission, and antioxidant/anti-inflammatory mechanisms in the brain. In a physiological state, both RAS axes remain balanced. However, some factors can dysregulate systemic and local RAS arms. The binding of SARS-CoV-2 to ACE2 causes the internalization and degradation of this enzyme, reducing its activity, and disrupting the balance of systemic and local RAS, which partially explain the appearance of some of the neurological symptoms associated with COVID-19. Therefore, this review aims to analyze the role of RAS in the development of the neurological effects due to SARS-CoV-2 infection. Moreover, we will discuss the RAS-molecular targets that could be used for therapeutic purposes to treat the short and long-term neurological COVID-19-related sequelae.

COVID-19-Associated Stroke

The COVID-19 pandemic has had significant influences on the incidence of acute cerebrovascular accidents and the structure of mortality. SARS-CoV-2 increases the risks of developing both ischemic and hemorrhagic stroke. The key pathogenetic element underlying the development of cerebral stroke in COVID-19 consists of impairments to the operation of angiotensin 2 receptors, which are accompanied by accumulation of excess quantities of angiotensin 2, endothelial dysfunction, hypercoagulation, overproduction of proinflammatory cytokines, and an oxidative storm. In patients with stroke and COVID-19, lesion severity is associated with dual mechanisms of ischemia - systemic and cerebral. The possibilities of medication-based correction of both systemic impairments associated with coronavirus infection and local impairments due to ischemic or hemorrhagic brain damage, are limited. Substances with antioxidant activity may potentially be effective in patients with stroke and COVID-19. Data from a number of clinical rials indicate that Mexidol significantly improves functional outcomes in ischemic stroke. Use of Mexidol in patients with stroke and COVID-19 is advised.

International Controlled Study of Revascularization and Outcomes Following COVID-Positive Mechanical Thrombectomy

Background and purpose

Previous studies suggest that mechanisms and outcomes in patients with COVID‐19‐associated stroke differ from those in patients with non‐COVID‐19‐associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID‐19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors.

Methods

A cross‐sectional, international multicenter retrospective study was conducted in consecutively admitted COVID‐19 patients with concomitant acute LVO, compared to a control group without COVID‐19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable‐adjusted analysis was conducted.

Results

In this cohort of 697 patients with acute LVO, 302 had COVID‐19 while 395 patients did not. There was a significant difference (p < 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID‐19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID‐19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23–0.48; p < 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12–0.77; p = 0.012). Moreover, endovascular complications, in‐hospital mortality, and length of hospital stay were significantly higher among COVID‐19 patients (p < 0.001).

Conclusion

COVID‐19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID‐19 patients with LVO were more often younger and had higher morbidity/mortality rates.

Incidence and predictors of organ failure among COVID-19 hospitalized adult patients in Eastern Ethiopia. Hospital-based retrospective cohort study

Background

Organ failure is incapability of at least one of the body organs to carry out a normal body functions. Identifying the predictors of the organ failure is crucial for improving COVID-19 patients’ survival. However, the evidence related to this information is not well-established in developing countries, including Ethiopia. Therefore, this study aimed to determine the incidence and predictors of organ failure among adult patients admitted to Hiwot Fana Specialized University Hospital (HFSUH) COVID-19 treatment center from 1st May 2020 to 20th August 2021, Eastern Ethiopia.

Methods

A hospital-based retrospective cohort study design was implemented. Descriptive measures such as mean with standard deviation (SD), median with interquartile range (IQR), percentages, and frequencies were computed. The binary logistic regression was used to identify the association between outcome variables (organ functional status) and independent variables with an adjusted odds ratio (AOR) at a 95% confidence interval. A significance level was declared at a p-value of less than 0.05.

Results

The mean age of study participants was 47.69 years with the standard deviation (SD) of ± 17.03. The study participants were followed for the median time of 8 days with IQR of 4, 14. The incidence of organ failure was 11.9 per 1000 person-day contribution (95% CI: 9.5, 14.9). Predictors such as age above 60 years (AOR = 1.71, 95% CI: 1.44, 4.53), smoking history (AOR = 5.07, 95% CI: 1.39, 8.15), cardiovascular disease (AOR = 5.00, 95% CI: (1.83, 11.72), and critical clinical stages of COVID-19 (AOR = 5.42, 95%: 1.47, 14. 84) were significantly associated with organ failure among COVID-19 hospitalized patients.

Conclusions

The incidence of organ failure was 11.9 per 1000 person-day contribution. Age, smoking, comorbidity, and clinical stages were significantly associated with organ failure among COVID-19 hospitalized cases. Therefore, clinicians should stringently follow the patients experiencing modifiable predictors of organ failure, especially patients with comorbidities and severe clinical stages. Moreover, the prevention programs that target elders and smokers should be strengthening to save this segment of populations before suffering from organ failure following COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07402-6.

Unhealthy Dieting During the COVID-19 Pandemic: An Opinion Regarding the Harmful Effects on Brain Health

Since 2020, the world has been suffering from a pandemic that has affected thousands of people regardless of socio-economic conditions, forcing the population to adopt different strategies to prevent and control the advance of the disease, one of which is social distancing. Even though social distancing is a safe strategy to reduce the spread of COVID-19, it is also the cause of a rising sedentary behavior. This behavior develops an excess of fat tissue that leads to metabolic and inflammatory disruption related to chronic diseases and mental health disorders, such as anxiety, depression, and sleep issues. Furthermore, the adoption of dietary patterns involving the consumption of ultra-processed foods, higher in fats and sugars, and the reduction of fresh and healthy foods may play a role in the progress of the disease. In this perspective, we will discuss how an unhealthy diet can affect brain function and, consequently, be a risk factor for mental health diseases.

Pathophysiology of Cardiac Injury in COVID-19 Patients with Acute Ischaemic Stroke: What Do We Know So Far?-A Review of the Current Literature

With the onset of the COVID-19 pandemic, it became apparent that, in addition to pulmonary infection, extrapulmonary manifestations such as cardiac injury and acute cerebrovascular events are frequent in patients infected with SARS-CoV-2, worsening clinical outcome. We reviewed the current literature on the pathophysiology of cardiac injury and its association with acute ischaemic stroke. Several hypotheses on heart and brain axis pathology in the context of stroke related to COVID-19 were identified. Taken together, a combination of disease-related coagulopathy and systemic inflammation might cause endothelial damage and microvascular thrombosis, which in turn leads to structural myocardial damage. Cardiac complications of this damage such as tachyarrhythmia, myocardial infarction or cardiomyopathy, together with changes in hemodynamics and the coagulation system, may play a causal role in the increased stroke risk observed in COVID-19 patients. These hypotheses are supported by a growing body of evidence, but further research is necessary to fully understand the underlying pathophysiology and allow for the design of cardioprotective and neuroprotective strategies in this at risk population.

Ischemic stroke in COVID-19 patients: Mechanisms, treatment, and outcomes in a consecutive Swiss Stroke Registry analysis

Background

Most case series of patients with ischemic stroke (IS) and COVID‐19 are limited to selected centers or lack 3‐month outcomes. The aim of this study was to describe the frequency, clinical and radiological features, and 3‐month outcomes of patients with IS and COVID‐19 in a nationwide stroke registry.

Methods

From the Swiss Stroke Registry (SSR), we included all consecutive IS patients ≥18 years admitted to Swiss Stroke Centers or Stroke Units during the first wave of COVID‐19 (25 February to 8 June 2020). We compared baseline features, etiology, and 3‐month outcome of SARS‐CoV‐2 polymerase chain reaction‐positive (PCR+) IS patients to SARS‐CoV‐2 PCR− and/or asymptomatic non‐tested IS patients.

Results

Of the 2341 IS patients registered in the SSR during the study period, 36 (1.5%) had confirmed COVID‐19 infection, of which 33 were within 1 month before or after stroke onset. In multivariate analysis, COVID+ patients had more lesions in multiple vascular territories (OR 2.35, 95% CI 1.08–5.14, p = 0.032) and fewer cryptogenic strokes (OR 0.37, 95% CI 0.14–0.99, p = 0.049). COVID‐19 was judged the likely principal cause of stroke in 8 patients (24%), a contributing/triggering factor in 12 (36%), and likely not contributing to stroke in 13 patients (40%).

There was a strong trend towards worse functional outcome in COVID+ patients after propensity score (PS) adjustment for age, stroke severity, and revascularization treatments (PS‐adjusted common OR for shift towards higher modified Rankin Scale (mRS) = 1.85, 95% CI 0.96–3.58, p = 0.07).

Conclusions

In this nationwide analysis of consecutive ischemic strokes, concomitant COVID‐19 was relatively rare. COVID+ patients more often had multi‐territory stroke and less often cryptogenic stroke, and their 3‐month functional outcome tended to be worse.

L, Kariyappa M, Devadas S, Kumble D, Sajjan SV, Rangegowda RK, Patel AS. Acute Ischemic Stroke in a Young Child and Its Association with SARS-CoV-2 Infection

The coronavirus disease 2019 (COVID-19) in children has been shown to have lower morbidity and mortality in children as compared with adults. The neurological complications related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are increasingly reported in children, yet the cerebrovascular complications are rare. We report a case of a toddler who presented with right-sided hemiparesis and motor aphasia, with an antecedent history suggestive of COVID-19 infection. The child tested negative on the nasopharyngeal swab for real-time reverse transcription-polymerase chain reaction (RT-PCR), but the serology for anti-SARS-CoV-2 IgG assay was positive. The neuroimaging showed an acute infarct in the left middle cerebral artery territory. A detailed evaluation for causes of childhood stroke was unrevealing, except for the presence of severe iron deficiency anemia (IDA). The child was diagnosed as acute ischemic stroke (AIS) most probably secondary to mild COVID-19 infection. The objective of this case report is to explain the possibility of AIS after a mild COVID-19 infection, complicated by the underlying severe IDA. Therefore, an association between COVID-19 and stroke in children needs to be emphasized and RT-PCR for SARS-CoV-2 as well as serological assay must be included in the workup of stroke in the young.

Neurological Manifestation of SARS-CoV-2 Induced Inflammation and Possible Therapeutic Strategies Against COVID-19

There are regular reports of extrapulmonary infections and manifestations related to the ongoing COVID-19 pandemic. Coronaviruses are potentially neurotropic, which renders neuronal tissue vulnerable to infection, especially in elderly individuals or in those with neuro-comorbid conditions. Complaints of ageusia, anosmia, myalgia, and headache; reports of diseases such as stroke, encephalopathy, seizure, and encephalitis; and loss of consciousness in patients with COVID-19 confirm the neuropathophysiological aspect of this disease. The brain is linked to pulmonary organs, physiologically through blood circulation, and functionally through the nervous system. The interdependence of these vital organs may further aggravate the pathophysiological aspects of COVID-19. The induction of a cytokine storm in systemic circulation can trigger a neuroinflammatory cascade, which can subsequently compromise the blood-brain barrier and activate microglia- and astrocyte-borne Toll-like receptors, thereby leading to neuronal tissue damage. Hence, a holistic approach should be adopted by healthcare professionals while treating COVID-19 patients with a history of neurodegenerative disorders, neuropsychological complications, or any other neuro-compromised conditions. Imperatively, vaccines are being developed at top priority to contain the spread of the severe acute respiratory syndrome coronavirus 2, and different vaccines are at different stages of development globally. This review discusses the concerns regarding the neuronal complications of COVID-19 and the possible mechanisms of amelioration.

Predicting COVID-19-Comorbidity Pathway Crosstalk-Based Targets and Drugs: Towards Personalized COVID-19 Management

It is well established that pre-existing comorbid conditions such as hypertension, diabetes, obesity, cardiovascular diseases (CVDs), chronic kidney diseases (CKDs), cancers, and chronic obstructive pulmonary disease (COPD) are associated with increased severity and fatality of COVID-19. The increased death from COVID-19 is due to the unavailability of a gold standard therapeutic and, more importantly, the lack of understanding of how the comorbid conditions and COVID-19 interact at the molecular level, so that personalized management strategies can be adopted. Here, using multi-omics data sets and bioinformatics strategy, we identified the pathway crosstalk between COVID-19 and diabetes, hypertension, CVDs, CKDs, and cancers. Further, shared pathways and hub gene-based targets for COVID-19 and its associated specific and combination of comorbid conditions are also predicted towards developing personalized management strategies. The approved drugs for most of these identified targets are also provided towards drug repurposing. Literature supports the involvement of our identified shared pathways in pathogenesis of COVID-19 and development of the specific comorbid condition of interest. Similarly, shared pathways- and hub gene-based targets are also found to have potential implementations in managing COVID-19 patients. However, the identified targets and drugs need further careful evaluation for their repurposing towards personalized treatment of COVID-19 cases having pre-existing specific comorbid conditions we have considered in this analysis. The method applied here may also be helpful in identifying common pathway components and targets in other disease-disease interactions too.

A Review on the Neurological Manifestations of COVID-19 Infection: a Mechanistic View

There is increasing evidence of neurological manifestations and complications in patients with coronavirus disease 19 (COVID-19). More than one-quarter of patients with COVID-19 developed various neurological symptoms, ranging from headache and dizziness to more serious medical conditions, such as seizures and stroke. The recent investigations introduced hyposmia as a potential early criterion of infection with COVID-19. Despite the high mortality and morbidity rate of COVID-19, its exact mechanism of action and pathogenesis is not well characterized. The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could interact with angiotensin-converting enzyme 2 (ACE2) in the endothelial, neural, and glial cells. In the present study, we reviewed the most common neurological manifestations and complications that emerged after infection with the SARS-CoV-2 and discussed their possible relation to the expression and function of ACE2. Comprehensive and detailed studies are required to uncover how this virus invades the neural system as well as other critical organs.

COVID-19 and cerebrovascular diseases: a comprehensive overview

Neurological manifestations are not uncommon during infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A clear association has been reported between cerebrovascular disease and coronavirus disease 2019 (COVID-19). However, whether this association is causal or incidental is still unknown. In this narrative review, we sought to present the possible pathophysiological mechanisms linking COVID-19 and cerebrovascular disease, describe the stroke syndromes and their prognosis and discuss several clinical, radiological, and laboratory characteristics that may aid in the prompt recognition of cerebrovascular disease during COVID-19. A systematic literature search was conducted, and relevant information was abstracted. Angiotensin-converting enzyme-2 receptor dysregulation, uncontrollable immune reaction and inflammation, coagulopathy, COVID-19-associated cardiac injury with subsequent cardio-embolism, complications due to critical illness and prolonged hospitalization can all contribute as potential etiopathogenic mechanisms leading to diverse cerebrovascular clinical manifestations. Acute ischemic stroke, intracerebral hemorrhage, and cerebral venous sinus thrombosis have been described in case reports and cohorts of COVID-19 patients with a prevalence ranging between 0.5% and 5%. SARS-CoV-2-positive stroke patients have higher mortality rates, worse functional outcomes at discharge and longer duration of hospitalization as compared with SARS-CoV-2-negative stroke patients in different cohort studies. Specific demographic, clinical, laboratory and radiological characteristics may be used as ‘red flags’ to alarm clinicians in recognizing COVID-19-related stroke.