Extracellular vesicles derived from SARS-CoV-2 infected cells induces neuroplastic changes in neuron-glia enriched cultures derived from human olfactory neuroepithelium.

• Grant number: 24/18340-7
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: February 17, 2025
• End date: August 16, 2025
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Alline Cristina de Campos
• Grantee: Bruno Lemes Marques
• Supervisor: Leyre Uriguen Echeverria
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: Universidad del País Vasco, Bizkaia (UPV), Spain
• Associated to the scholarship: 23/05979-7 - Cannabidiol mitigates the long-term cognitive effects produced by the signaling pathway mediated by exosomes derived from neural cells infected with SARS-CoV-2: standardization of a cognitive model for long COVID., BP.DR

Abstract

As the incidence of new Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infections has decreased, the World Health Organization has declared the SARS-CoV-2 pandemic to be over. However, the impact of this viral outbreak may last longer with the occurrence of neurological and psychiatric symptoms in those infected with SARS-CoV-2 several months after the display of primary respiratory symptoms. A significant mechanism for the dissemination of viral particles is the production and distribution of extracellular vesicles (EVs). EVs are nanoparticles secreted by several cell types that plays a fundamental role in intercellular communication. Recent studies have revealed compositional changes in circulating EV cargo, both over the longitudinal course of the disease and at different stages of COVID-19 severity. SARS-CoV-2-induced changes in EV composition could be associated with increased neuroinvasiveness and the production of pro-inflammatory factors, which may lead to neurological alterations linked to neuroinflammatory processes. Interestingly, studies have demonstrated that cannabidiol (CBD), a non-psychotomimetic phytocannabinoid derived from Cannabis sativa, attenuates neuroinflammatory processes and alleviates cognitive impairments in animal models of neurodegenerative diseases. Considering that persistent inflammatory mediators and neuroinflammation may explain neurological and psychiatric symptoms in long COVID, CBD treatment may offer neuroprotective effects and alleviate these symptoms. In this way, we hypothesize that extracellular vesicles are pivotal in the mechanisms of neuroinvasiveness and cognitive impairments linked to long COVID, and that CBD treatment may mitigate these effects by reducing the pro-inflammatory cargo of these vesicles. To investigate this, we plan to employ a translational in vitro model using primary cultures derived from biopsies of the olfactory neuroepithelium. Extracellular vesicles isolated from SH-SY5Y cells (neuroblastoma cells) infected with SARS-CoV-2 or MOCK will be administered to neuron-enriched and glia-enriched cells derived from human olfactory neuroepithelium for 24 hours. After this period, cells will be treated with CBD (0.3 and 3 µM) for 24h. Then, BrdU incorporation and MTT assays for cell viability will be conducted Moreover, cellular senescence will be evaluated using immunofluorescence techniques. The number of SA-¿-gal+ cells will be quantified to determine cellular senescence. Normality of distribution will be assessed using the Shapiro-Wilk test. Kurtosis and skewness coefficients will be calculated to verify if numerical variables follow a normal distribution. Chi-square or Fisher's exact tests will be used to analyze categorical variables, while Mann-Whitney and One-way ANOVA tests will be employed to compare numerical variables. P-values less than 0.05 will be considered significant, with a 95% confidence interval. All data will be presented as mean ± standard error of mean and analyzed using R (Version 4.4.1).