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The COVID-19 pandemic, caused by infection with the SARS-CoV-2 virus, is associated with cognitive impairment and Alzheimer's disease (AD) progression. Once it enters the brain, the SARS-CoV-2 virus stimulates accumulation of amyloids in the brain that are highly toxic to neural cells. These amyloids may trigger neurological symptoms in COVID-19. The meningeal lymphatic vessels (MLVs) play an important role in removal of toxins and mediate viral drainage from the brain. MLVs are considered a promising target to prevent COVID-19-exacerbated dementia. However, there are limited methods for augmentation of MLV function. This review highlights new discoveries in the field of COVID-19-mediated amyloid accumulation in the brain associated with the neurological symptoms and the development of promising strategies to stimulate clearance of amyloids from the brain through lymphatic and other pathways. These strategies are based on innovative methods of treating brain dysfunction induced by COVID-19 infection, including the use of photobiomodulation, plasmalogens, and medicinal herbs, which offer hope for addressing the challenges posed by the SARS-CoV-2 virus.
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The blood-brain barrier (BBB) poses a significant challenge for drug delivery to the brain. Therefore, the development of safe methods for an effective delivery of medications to the brain can be a revolutionary step in overcoming this limitation. Using a quantum-dot-based 1267 nm laser (photosensitiser-free generation of singlet oxygen), we clearly show the photostimulation of lymphatic delivery of bevacizumab (BMZ) to the brain tissues and the meninges. These pilot findings open promising perspectives for photomodulation of a lymphatic brain drug delivery bypassing the BBB, and potentially enabling a breakthrough strategy in therapy of glioma using BMZ and other chemotherapy drugs.
Assuntos
Vasos Linfáticos , Oxigênio Singlete , Bevacizumab , Encéfalo , Barreira Hematoencefálica , Sistemas de Liberação de MedicamentosRESUMO
Background: The development of new methods for modulation of drug distribution across to the brain is a crucial step in the effective therapies for glioblastoma (GBM). In our previous work, we discovered the phenomenon of music-induced opening of the blood-brain barrier (OBBB) in healthy rodents. In this pilot study on rats, we clearly demonstrate that music-induced BBB opening improves the therapeutic effects of bevacizumab (BZM) in rats with GBM via increasing BZM distribution to the brain along the cerebral vessels. Methods: The experiments were performed on Wistar male rats (200-250 g, n=161) using transfected C6-TagRFP cell line and the loud rock music for OBBB. The OBBB was assessed by spectrofluorometric assay of Evans Blue (EB) extravasation and confocal imaging of fluorescent BZM (fBZM) delivery into the brain. Additionally, distribution of fBZM and Omniscan in the brain was studied using fluorescent and magnetic resonance imaging (MRI), respectively. To analyze the therapeutic effects of BZM on the GBM growth in rats without and with OBBB, the GBM volume (MRI scans), as well as immunohistochemistry assay of proliferation (Ki67 marker) and apoptosis (Bax marker) in the GBM cells were studied. The Mann-Whitney-Wilcoxon test was used for all analysis, the significance level was p < 0.05, n=7 in each group. Results: Our finding clearly demonstrates that music-induced OBBB increases the delivery of EB into the brain tissues and the extravasation of BZM into the brain around the cerebral vessels of rats with GBM. Music significantly increases distribution of tracers (fBZM and Omniscan) in the rat brain through the pathways of brain drainage system (perivascular and lymphatic), which are an important route of drug delivery into the brain. The music-induced OBBB improves the suppressive effects of BZM on the GBM volume and the cellular mechanisms of tumor progression that was accompanied by higher survival among rats in the GBM+BZM+Music group vs. other groups. Conclusion: We hypothesized that music improves the therapeutic effects of BZM via OBBB in the normal cerebral vessels and lymphatic drainage of the brain tissues. This contributes better distribution of BZM in the brain fluids and among the normal cerebral vessels, which are used by GBM for invasion and co-opt existing vessels as a satellite tumor form. These results open the new perspectives for an improvement of therapeutic effects of BZM via the music-induced OBBB for BZM in the normal cerebral vessels, which are used by GBM for migration and progression.
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The genetic structure of EBV LMP1 alleles isolated from tumor, blood, and throat washing samples of 22 nasopharyngeal carcinoma patients, 17 patients with other non-EBV-related tumors of the oral cavity, and 19 blood donors have been studied in representatives of Central Russia and the Republics of Northern Caucasus, regions which are non-endemic for nasopharyngeal carcinoma. The analysis of the LMP1 alleles collected revealed that they practically matched previously described LMP1 variants; however, some characteristic features were also detected. In particular, the G212S substitution in LMP1 isolates investigated was not observed at all. Tumor samples obtained from nasopharyngeal carcinoma and other tumors of the oral cavity did not differ significantly either in the frequency of "high oncogenic" LMP1 alleles with 10 aa and/or 23 aa deletions (LMP1(China1) and/or LMP1(Med+)), nor in the number of 11 aa repeats and the frequency of 5 aa motif insertions. No differences in the frequency of amino acid substitutions between LMP1 alleles obtained from tumor and throat washing samples of both patient groups were also detected. The data obtained may indicate that in both nasopharyngeal carcinoma patients and patients with other tumors of the oral cavity, the EBV strains with similar LMP1 variants are found to persist. This observation allows us to suggest that in non-endemic areas, EBV strains with any LMP1 alleles can initiate the nasopharyngeal carcinoma development but only in those individuals who have a genetic predisposition to the disease and are subjected to specific environmental, and/or dietary factors present in certain geographic areas.
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Variação Genética , Herpesvirus Humano 4/classificação , Herpesvirus Humano 4/genética , Neoplasias Bucais/virologia , Neoplasias Nasofaríngeas/virologia , Proteínas da Matriz Viral/genética , Sequência de Aminoácidos , Doadores de Sangue , Carcinoma , Análise por Conglomerados , Feminino , Voluntários Saudáveis , Herpesvirus Humano 4/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Carcinoma Nasofaríngeo , Filogenia , Federação Russa , Alinhamento de SequênciaRESUMO
Multiple sclerosis (MS) is a widespread neurodegenerative autoimmune disease with unknown etiology. It is increasingly evident that, together with pathogenic T cells, autoreactive B cells are among the major players in MS development. The analysis of myelin neuroantigen-specific antibody repertoires and their possible cross-reactivity against environmental antigens, including viral proteins, could shed light on the mechanism of MS induction and progression. A phage display library of single-chain variable fragments (scFvs) was constructed from blood lymphocytes of patients with MS as a potential source of representative MS autoantibodies. Structural alignment of 13 clones selected toward myelin basic protein (MBP), one of the major myelin antigens, showed high homology within variable regions with cerebrospinal fluid MS-associated antibodies as well as with antibodies toward Epstein-Barr latent membrane protein 1 (LMP1). Three scFv clones showed pronounced specificity to MBP fragments 65-92 and 130-156, similar to the serum MS antibodies. One of these clones, designated E2, in both scFv and full-size human antibody constructs, was shown to react with both MBP and LMP1 proteins in vitro, suggesting natural cross-reactivity. Thus, antibodies induced against LMP1 during Epstein-Barr virus infection might act as inflammatory trigger by reacting with MBP, suggesting molecular mimicry in the mechanism of MS pathogenesis.