Can SARS-CoV-2 Infection Exacerbate Alzheimer’s Disease? An Overview of Shared Risk Factors and Pathogenetic Mechanisms

The current coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2, is affecting every aspect of global society, including public healthcare systems, medical care access, and the economy. Although the respiratory tract is primarily affected by SARS-CoV-2, emerging evidence suggests that the virus may also reach the central nervous system (CNS), leading to several neurological issues. In particular, people with a diagnosis of Alzheimer’s disease (AD) are a vulnerable group at high risk of contracting COVID-19, and develop more severe forms and worse outcomes, including death. Therefore, understanding shared links between COVID-19 and AD could aid the development of therapeutic strategies against both. Herein, we reviewed common risk factors and potential pathogenetic mechanisms that might contribute to the acceleration of neurodegenerative processes in AD patients infected by SARS-CoV-2.

Pathogenetic mechanisms of sensorineural hearing loss in patients with COVID-19 and methods for their correction

The article describes the main pathogenetic mechanisms of acute sensorineural hearing loss, including that caused by infection. Possible risk factors and mechanisms of development of sensorineural hearing loss against the background of coronavirus infection caused by SARS-CoV-2 virus are consi-dered. Cases of hearing loss in patients with COVID-19 have been described. The pathogenetically substantiated therapeutic approach to the treatment of such patients is presented, it is based on the optimization of acetylcholine neurotransmission in the brain structures involved in the conduction and perception of the auditory impulse.

Perspectives and potential approaches for targeting neuropilin 1 in SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel type b coronavirus responsible for the COVID-19 pandemic. With over 224 million confirmed infections with this virus and more than 4.6 million people dead because of it, it is critically important to define the immunological processes occurring in the human response to this virus and pathogenetic mechanisms of its deadly manifestation. This perspective focuses on the contribution of the recently discovered interaction of SARS-CoV-2 Spike protein with neuropilin 1 (NRP1) receptor, NRP1 as a virus entry receptor for SARS-CoV-2, its role in different physiologic and pathologic conditions, and the potential to target the Spike–NRP1 interaction to combat virus infectivity and severe disease manifestations.

The link between atopic dermatitis and asthma- immunological imbalance and beyond

Atopic diseases are multifactorial chronic disturbances which may evolve one into another and have overlapping pathogenetic mechanisms. Atopic dermatitis is in most cases the first step towards the development of the atopic march and represents a major socio-economic burden in the industrialized countries. The treatment of atopic diseases is often long-lasting and in some cases with lower effectiveness than expected.In order to prevent the development of the atopic march, the links between the atopic diseases have to be understood. The aim of this review is to present some major points outlining the link between atopic dermatitis and asthma, through a research in the medical literature from recent years.Stratifying patient populations according to the clinical phenotype of their disease and according to specific measurable values (biomarkers) can help to establish the main etiopathogenetic mechanisms of the disease in these populations. This will add predictive value for the evolution of the disease, and will allow the use and research of more targeted therapy in order to stop this evolution and comorbidities.

Unusual Reactions to Hymenoptera Stings: Current Knowledge and Unmet Needs in the Pediatric Population

Hymenoptera stings are generally well-tolerated and usually cause limited local reactions, characterized by self-resolving erythema and edema associated with pain. However, Hymenoptera stings can induce immediate and delayed hypersensitivity reactions. In addition to these manifestations, unusual reactions to Hymenoptera stings have been reported. The latter are defined as unusual because of their atypical characteristics. They may differ from classical hypersensitivity reactions due to the stings' particular localization and the unusual involvement of one or more specific organs. Although unusual reactions to Hymenoptera stings are infrequent, it is essential for clinicians to know the possible related clinical manifestations. Here, we review the available literature and propose a diagnostic and management algorithm. At present, there are no defined guidelines for most of the unusual reactions to Hymenoptera stings, which should be managed in a tailored way according to the specifical clinical manifestations presented by the patients. Further studies are needed to better define these conditions and the underlying pathogenetic mechanisms to improve the diagnostic and therapeutic approach.

Genetics of familial amyotrophic lateral sclerosis

To analyze results of the studies covering modern scientific views on the genetics of familial amyotrophic lateral sclerosis (FALS).We searched for full-text publications containing the key words “amyotrophic lateral sclerosis”, “FALS”, and “genetics” in the literature for the past 10 years in both Russian and English in eLibrary, PubMed, Web of Science, and OMIM databases. In addition, the review includes earlier publications of historical interest.This review summarizes all existing information on four most widespread genes associated with FALS: SOD1, TARDBP, FUS, and C9ORF72. The review also describes the functions of these genes and possible pathogenetic mechanisms of motor neuron death in amyotrophic lateral sclerosis (ALS), such as mitochondrial dysfunction, oxidative stress, glutamate excitotoxicity, damage to axonal transport components, and pathological neurofilament aggregation.As modern methods of molecular genetic diagnostics evolve, our knowledge about multifactorial FALS genetics expands. This information should be taken into consideration in clinical practice of neurologists. Information about the genes associated with ALS and understanding of particular pathogenetic mechanisms of the disease play a key role in the development of effective therapeutic strategies.

AGGRESSIVE BEHAVIOR CORRECTION BY THE TRANSPLANTATION OF IN VITRO MODULATED IMMUNE CELLS

Aggression is a serious biomedical problem associated with a high percentage of patients and a lack of selective corrective agents. The most frequent increase in aggressiveness occurs in patients with depressive disorders, schizophrenia, reactive psychoses and adjustment disorders, which are known to be characterized by immunological dysfunction. Antipsychotics are widely used in the correction of psychomotor agitation; the antipsychotic effect of these drugs is manifested in the achievement of a sedative effect. However, like other psychoactive substances, they have a number of side effects that limit their long-term use and determines the need to search for new approaches to the correction of affective disorders. Experimental modeling of aggression is one of the main approaches for studying its pathogenetic mechanisms and searching for new effective therapeutic agents for the treatment. The study of the aggression pathogenetic mechanisms and the search for approaches to therapy within the framework of neuroimmune interaction is currently extremely promising. Currently, there is a large number of clinical and experimental data indicating interrelated changes in the functional activity of the nervous and immune systems during aggression. The leading links in the pathogenetic mechanism of aggression is the violation of the production and mutual regulation of cytokines, neurotransmitters, neuropeptides, growth factors, hormones, the effects of which are mediated by the cellular elements of the immune system. Given the immune cells essential role in the pathogenesis of aggression and the psychoactive substances unidirectional effect on the immune and nervous cells, make it possible to consider immune cells as model objects for influencing the intersystem functional relationship in order to edit the aggressive phenotype. The aim of the study was to investigate the effect of in vitro neuroleptic-modulated immune cells transplantation on behavioral phenotype and brain cytokines in aggressive syngeneic recipients. Aggressive behavior was formed in active male mice (CBA × C57Bl/6) F1 as a result of the experience of 20- fold victories in inter-male confrontations (distant sensory contact model). Aggressive mice splenocytes were treated in vitro with chlorpromazine and intravenously injected to syngeneic aggressive recipients. It has been demonstrated that modulated in vitro by chlorpromazine splenocytes of aggressive mice after transplantation edit the syngeneic aggressive recipient’s behavior against the background of a decrease in cytokines IL-1β, IL-2, IL-6, IFNγ and an increase in IL-4 in pathogenetically significant for aggression brain structures. The mechanisms of the aggressive behavior correcting effect of modulated immune cells are discussed.

Investigating Pathogenetic Mechanisms of Alzheimer’s Disease by Systems Biology Approaches for Drug Discovery

Alzheimer’s disease (AD) is the most common cause of dementia, characterized by progressive cognitive decline and neurodegenerative disorder. Abnormal aggregations of intracellular neurofibrillary tangles (NFTs) and unusual accumulations of extracellular amyloid-β (Aβ) peptides are two important pathological features in AD brains. However, in spite of large-scale clinical studies and computational simulations, the molecular mechanisms of AD development and progression are still unclear. In this study, we divided all of the samples into two groups: early stage (Braak score I-–III) and later stage (Braak score IV–VI). By big database mining, the candidate genetic and epigenetic networks (GEN) have been constructed. In order to find out the real GENs for two stages of AD, we performed systems identification and system order detection scheme to prune false positives with the help of corresponding microarray data. Applying the principal network projection (PNP) method, core GENs were extracted from real GENs based on the projection values. By the annotation of KEGG pathway, we could obtain core pathways from core GENs and investigate pathogenetic mechanisms for the early and later stage of AD, respectively. Consequently, according to pathogenetic mechanisms, several potential biomarkers are identified as drug targets for multiple-molecule drug design in the treatment of AD.

What Is in the Field for Genetics and Epigenetics of Diabetic Neuropathy: The Role of MicroRNAs

Despite the high prevalence of diabetic neuropathy, its early start, and its impact on quality of life and mortality, unresolved clinical issues persist in the field regarding its screening implementation, the understanding of its mechanisms, and the search for valid biomarkers, as well as disease-modifying treatment. Genetics may address these needs by providing genetic biomarkers of susceptibility, giving insights into pathogenesis, and shedding light on how to select possible responders to treatment. After a brief summary of recent studies on the genetics of diabetic neuropathy, the current review focused mainly on microRNAs (miRNAs), including the authors’ results in this field. It summarized the findings of animal and human studies that associate miRNAs with diabetic neuropathy and explored the possible pathogenetic meanings of these associations, in particular regarding miR-128a, miR-155a, and miR-499a, as well as their application for diabetic neuropathy screening. Moreover, from a genetic perspective, it examined new findings of polymorphisms of miRNA genes in diabetic neuropathy. It considered in more depth the pathogenetic implications for diabetic neuropathy of the polymorphism of MIR499A and the related changes in the downstream action of miR-499a, showing how epigenetic and genetic studies may provide insight into pathogenetic mechanisms like mitochondrial dysfunction. Finally, the concept and the data of genotype-phenotype association for polymorphism of miRNA genes were described. In conclusion, although at a very preliminary stage, the findings linking the genetics and epigenetics of miRNAs might contribute to the identification of exploratory risk biomarkers, a comprehensive definition of susceptibility to specific pathogenetic mechanisms, and the development of mechanism-based treatment of diabetic neuropathy, thus addressing the goals of genetic studies.