Creutzfeldt-Jakob disease after COVID-19: infection-induced prion protein misfolding? A case report

The molecular fingerprint of neuroinflammation in COVID-19: A comprehensive discussion on molecular mechanisms of neuroinflammation due to SARS-COV2 antigens

BACKGROUND AND OBJECTIVE

Severe acute respiratory syndrome coronavirus 2 attacks the neural system directly and indirectly via various systems, such as the nasal cavity, olfactory system, and facial nerves. Considering the high energy requirement, lack of antioxidant defenses, and high amounts of metal ions in the brain, oxidative damage is very harmful to the brain. Various neuropathic pain conditions, neurological disorders, and neuropsychiatric complications were reported in Coronavirus disease 2019, prolonged Coronavirus disease 2019, and after Coronavirus disease 2019 immunization. This manuscript offers a distinctive outlook on the interconnectedness between neurology and neuropsychiatry through its meticulous analysis of complications.

DISCUSSION

After recovering from Coronavirus disease 2019, approximately half of the patients reported developing Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Long Coronavirus disease 2019 imaging reports illustrated the hypometabolism in various parts of the brain, such as olfactory bulbs, limbic/paralimbic domains, the brainstem, and the cerebellum. Ninety imaging and neuropathological studies of Coronavirus disease 2019 have shown evidence of white matter, brainstem, frontotemporal, and oculofrontal lesions. Emotional functions, such as pleasant, long/short-term memory, movement, cognition and cognition in decision-making are controlled by these regions. The neuroinflammation and the mechanisms of defense are well presented in the discussion. The role of microglia activation, Inducible NO synthase, Cyclooxygenases ½, Reactive oxygen species, neurotoxic toxins and pro-inflammatory cytokines, such as Interleukin-1 beta, Interleukin-6 and Tumor Necrosis Factor-alpha are highlighted in neuronal dysfunction and death. Nuclear factor kappa-light-chain-enhancer of activated B cells, Mitogen-activated protein kinase, Activator Protein 1, and Interferon regulatory factors are the main pathways involved in microglia activation in Coronavirus disease 2019 neuroinflammation.

CONCLUSION

The neurological aspect of Coronavirus disease 2019 should be highlighted. Neurological, psychological, and behavioral aspects of Coronavirus disease 2019, prolonged Coronavirus disease 2019, and Coronavirus disease 2019 vaccines can be the upcoming issues. We need a global awareness where this aspect of the disease should be more considered in health research.

Extracellular Vesicles: The Invisible Heroes and Villains of COVID-19 Central Neuropathology

Acknowledging the neurological symptoms of COVID-19 and the long-lasting neurological damage even after the epidemic ends are common, necessitating ongoing vigilance. Initial investigations suggest that extracellular vesicles (EVs), which assist in the evasion of the host's immune response and achieve immune evasion in SARS-CoV-2 systemic spreading, contribute to the virus's attack on the central nervous system (CNS). The pro-inflammatory, pro-coagulant, and immunomodulatory properties of EVs contents may directly drive neuroinflammation and cerebral thrombosis in COVID-19. Additionally, EVs have attracted attention as potential candidates for targeted therapy in COVID-19 due to their innate homing properties, low immunogenicity, and ability to cross the blood-brain barrier (BBB) freely. Mesenchymal stromal/stem cell (MSCs) secreted EVs are widely applied and evaluated in patients with COVID-19 for their therapeutic effect, considering the limited antiviral treatment. This review summarizes the involvement of EVs in COVID-19 neuropathology as carriers of SARS-CoV-2 or other pathogenic contents, as predictors of COVID-19 neuropathology by transporting brain-derived substances, and as therapeutic agents by delivering biotherapeutic substances or drugs. Understanding the diverse roles of EVs in the neuropathological aspects of COVID-19 provides a comprehensive framework for developing, treating, and preventing central neuropathology and the severe consequences associated with the disease.

Rapid progression of probable Creutzfeldt-Jakob disease with concomitant COVID-19 infection

A previously healthy man in his 80s was admitted to a district general hospital with rapidly progressing dementia, gait abnormalities and myoclonus alongside COVID-19 infection. Investigations showed mild elevation of C-reactive protein and neutrophils, unremarkable CT head and mildly raised protein in cerebrospinal spinal fluid (CSF). Brain MRI revealed bilateral cortical and striatal diffusion restriction and electroencephalogram (EEG) findings showed diffuse activity slowing with high amplitude sharp/slow-wave complexes. He was diagnosed with probable sporadic Creutzfeldt-Jakob disease (CJD) and management prioritised comfort and care. He passed away two weeks following admission and a mere 8 weeks after the first onset of symptoms.We present the first documented case of probable CJD with concomitant COVID-19 infection in the UK. We identified six other cases worldwide identified in our literature review. These cases suggest a role of COVID-19 in the rapid progression of CJD and add to the growing evidence of its neuroinflammatory role in other forms of neurodegenerative diseases.

Prion Disease After COVID-19: A Case Report

BACKGROUND Prion disease (PrD) is one of the rapidly progressive dementias. It typically requires several diagnostic criteria to fulfill a probable diagnosis, as definite diagnosis is based on isolated brain biopsy. There has been much debate on a possible infectious etiology of PrD. Viral infections are commonly pathologic in most neurodegenerative conditions. In PrD, misfolded proteins can be contagious and act as infective proteins, regardless of the pathologic agent. There is evidence that COVID-19 can result in neurologic manifestations, and neurodegeneration has been reported in the literature. There are several case reports describing parkinsonism after COVID-19, with Parkinson's disease in particular noted in COVID-19. Few cases of PrD were reported after COVID-19 infection. We identified 1 case of PrD in the setting of COVID-19 at our hospital. CASE REPORT We report the case of a 62-year-old man admitted to Mount Sinai Queens Hospital Center, who presented with rapidly progressive dementia along with difficulty walking and myoclonus. All workup results were negative. He underwent MRI brain, but results were not revealing. Due to the high clinical suspicion, CSF protein 14-3-3 testing was ordered and was positive. Clinically, he experienced worsening neurological function after having been COVID-19-positive on admission. The case fulfilled the probable diagnostic criteria for diagnosing PrD. The patient continued to deteriorate and died due to the rapid progression of his condition. CONCLUSIONS Our case demonstrates the potential correlation of COVID with neurodegenerative conditions, especially prion disorders. While such cases are highly likely to be due to COVID-19, there is no definite evidence beyond coincidental findings. Future studies might be required to establish this correlation.

Sporadic Creutzfeldt-Jakob Disease With COVID-19 Infection: A Case Report

Creutzfeldt-Jakob disease (CJD) is a rare and rapidly fatal neurological disease. Diagnosis is made through clinical features, imaging, electroencephalography, and cerebrospinal fluid analysis. Sporadic CJD accounts for the majority of cases and occurs due to somatic mutation in the gene or random structural change in the prion protein. Coronavirus disease 2019 (COVID-19) is known to cause neurodegeneration, and CJD acceleration is hypothesized due to systemic inflammatory response and prion misfolding. We present a 70-year-old lady with rapidly progressing dementia diagnosed as CJD, with the onset coinciding with COVID-19 infection.

Case report: Creutzfeldt-Jakob disease presenting with anxiety symptoms in a COVID-19 post-infection patient

Creutzfeldt-Jakob Disease (CJD) is a rare, rapidly progressive, and fatal neurodegenerative disorder. We describe a man whose initial manifestations of CJD occurred shortly after contracting Coronavirus disease 2019 (COVID-19). He first developed anxiety and short-term memory loss a few weeks after a mild COVID-19 infection. He subsequently developed parkinsonism, eventually progressed to akinetic mutism, and passed away 5 months after symptom onset. This case highlights a potential temporal relationship between COVID-19 infection and the onset of neurodegenerative symptoms. Microglia and astrocytes in the central nervous system (CNS) and 'S1' spike proteins on SARS-CoV-2 are potential mediators in neuroinflammation and neurodegeneration.

A Theoretical Framework on the Biology of Prion Diseases

Background

Prion diseases or TSE diseases are a group of neurodegenerative disorders that manifest in several forms in humans, such as Kuru disease, Creutzfeldt‒Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS) and fatal familial insomnia.

Objective

In this study, we propose a multimodular hypothesis of prion diseases. According to this hypothesis, a prion disease manifests because of the interaction of two genetic modules, such as the PRNP gene module and that of the gene or genes responsible for one or more chaperones, with one or some chemical module on whose structure the products of the genes or genetic modules interact.

Methods

This study presents the perspective that modular thinking can allow us to overcome conceptual obstacles in the understanding and interpretation of prion diseases.

Results and Discussion

The structure of the chemical module or modules is directly responsible for the folding or misfolding of the PrPC protein. The etiology of acquired prion diseases is explained based on this hypothesis. Hence, it has been proposed that (g) CJD involves the PRNP gene mutant and one or more mutant genes for one or more chaperone genes. In contrast, sCJD has one or more mutant chaperone genes. When does iCJD occur? Healthy individuals manifest acquired prion disease through contamination when infected with one or more mutant chaperones. The mutant chaperones interact with the prion protein, and PrPC is converted to its isoform PrPSc. In a recent study, there was a case of an individual with CJD after COVID-19 infection.

Conclusion

This case emphasizes the link between neuroinflammation and protein misfolding and provides proof that chemical module formation is a necessary condition for the manifestation of prion diseases.

NLRP3 Inflammasome’s Activation in Acute and Chronic Brain Diseases—An Update on Pathogenetic Mechanisms and Therapeutic Perspectives with Respect to Other Inflammasomes

Increasingly prevalent acute and chronic human brain diseases are scourges for the elderly. Besides the lack of therapies, these ailments share a neuroinflammation that is triggered/sustained by different innate immunity-related protein oligomers called inflammasomes. Relevant neuroinflammation players such as microglia/monocytes typically exhibit a strong NLRP3 inflammasome activation. Hence the idea that NLRP3 suppression might solve neurodegenerative ailments. Here we review the recent Literature about this topic. First, we update conditions and mechanisms, including RNAs, extracellular vesicles/exosomes, endogenous compounds, and ethnic/pharmacological agents/extracts regulating NLRP3 function. Second, we pinpoint NLRP3-activating mechanisms and known NLRP3 inhibition effects in acute (ischemia, stroke, hemorrhage), chronic (Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, MS, ALS), and virus-induced (Zika, SARS-CoV-2, and others) human brain diseases. The available data show that (i) disease-specific divergent mechanisms activate the (mainly animal) brains NLRP3; (ii) no evidence proves that NLRP3 inhibition modifies human brain diseases (yet ad hoc trials are ongoing); and (iii) no findings exclude that concurrently activated other-than-NLRP3 inflammasomes might functionally replace the inhibited NLRP3. Finally, we highlight that among the causes of the persistent lack of therapies are the species difference problem in disease models and a preference for symptomatic over etiologic therapeutic approaches. Therefore, we posit that human neural cell-based disease models could drive etiological, pathogenetic, and therapeutic advances, including NLRP3’s and other inflammasomes’ regulation, while minimizing failure risks in candidate drug trials.

miRNAs as a Potential Biomarker in the COVID-19 Infection and Complications Course, Severity, and Outcome

During the last three years, since the emergence of the COVID-19 pandemic, a significant number of scientific publications have focused on resolving susceptibility to the infection, as well as the course of the disease and potential long-term complications. COVID-19 is widely considered as a multisystem disease and a variety of socioeconomic, medical, and genetic/epigenetic factors may contribute to the disease severity and outcome. Furthermore, the SARS-COV-2 infection may trigger pathological processes and accelerate underlying conditions to clinical entities. The development of specific and sensitive biomarkers that are easy to obtain will allow for patient stratification, prevention, prognosis, and more individualized treatments for COVID-19. miRNAs are proposed as promising biomarkers for different aspects of COVID-19 disease (susceptibility, severity, complication course, outcome, and therapeutic possibilities). This review summarizes the most relevant findings concerning miRNA involvement in COVID-19 pathology. Additionally, the role of miRNAs in wide range of complications due to accompanied and/or underlying health conditions is discussed. The importance of understanding the functional relationships between different conditions, such as pregnancy, obesity, or neurological diseases, with COVID-19 is also highlighted.

Creutzfeldt-Jakob Disease in a Patient with Previous COVID-19 Infection: "The Virus Caused the Derangement in My Brain"

Recent studies have speculated a link between Creutzfeldt-Jakob disease (CJD) and COVID-19, following the description of CJD cases after COVID-19 infection. We report the case of a 71-year-old female patient who developed neuropsychiatric and neurological symptoms after COVID-19 infection and was later diagnosed with CJD. Cerebrospinal fluid (CSF) total tau levels were slightly increased. She resulted prion protein gene (PRNP) M129V heterozygous. We aim to emphasize the role of the polymorphism at codon 129 of PRNP gene on the clinical phenotype and duration of CJD, and the CSF total tau levels that likely correlate with the rate of disease progression.

SARS-CoV-2 Invasion and Pathological Links to Prion Disease

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 disease, is a highly infectious and transmissible viral pathogen that continues to impact human health globally. Nearly ~600 million people have been infected with SARS-CoV-2, and about half exhibit some degree of continuing health complication, generically referred to as long COVID. Lingering and often serious neurological problems for patients in the post-COVID-19 recovery period include brain fog, behavioral changes, confusion, delirium, deficits in intellect, cognition and memory issues, loss of balance and coordination, problems with vision, visual processing and hallucinations, encephalopathy, encephalitis, neurovascular or cerebrovascular insufficiency, and/or impaired consciousness. Depending upon the patient’s age at the onset of COVID-19 and other factors, up to ~35% of all elderly COVID-19 patients develop a mild-to-severe encephalopathy due to complications arising from a SARS-CoV-2-induced cytokine storm and a surge in cytokine-mediated pro-inflammatory and immune signaling. In fact, this cytokine storm syndrome: (i) appears to predispose aged COVID-19 patients to the development of other neurological complications, especially those who have experienced a more serious grade of COVID-19 infection; (ii) lies along highly interactive and pathological pathways involving SARS-CoV-2 infection that promotes the parallel development and/or intensification of progressive and often lethal neurological conditions, and (iii) is strongly associated with the symptomology, onset, and development of human prion disease (PrD) and other insidious and incurable neurological syndromes. This commentary paper will evaluate some recent peer-reviewed studies in this intriguing area of human SARS-CoV-2-associated neuropathology and will assess how chronic, viral-mediated changes to the brain and CNS contribute to cognitive decline in PrD and other progressive, age-related neurodegenerative disorders.