RESUMEN
The World Health Organization declared the novel coronavirus, named as SARS-CoV-2, as a global pandemic in early 2020 after the disease spread to more than 180 countries leading to tens of thousands of cases and many deaths within a couple of months. Consequently, this paper aims to summarize the evidence for the relationships between nutrition and the boosting of the immune system in the fight against the disease caused by SARS-CoV-2. This review, in particular, assesses the impact of vitamin and mineral supplements on the body's defence mechanisms against SARS-CoV-2. The results revealed that there is a strong relationship between the ingestion of biological ingredients like vitamins C-E, and minerals such as zinc, and a reduction in the effects of coronavirus infection. These can be received from either nutrition rich food sources or from vitamin supplements. Furthermore, these macromolecules might have roles to play in boosting the immune response, in the healing process and the recovery time. Hence, we recommend that eating healthy foods rich in vitamins C-E with zinc and flavonoids could boost the immune system and consequently protect the body from serious infections.
RESUMEN
Polyethylene glycol (PEG) coating has been frequently used to improve the pharmacokinetic behavior of nanoparticles. Studies that contribute to better unravel the effects of PEGylation on the toxicity of nanoparticle formulation are therefore highly relevant. In the present study, reduced graphene oxide (rGO) was functionalized with PEG, and its effects on key components of the blood-brain barrier, such as astrocytes and endothelial cells, were analyzed in culture and in an in vivo rat model. The in vitro studies demonstrated concentration-dependent toxicity. The highest concentration (100 µg/mL) of non-PEGylated rGO had a lower toxic influence on cell viability in primary cultures of astrocytes and rat brain endothelial cells, while PEGylated rGO induced deleterious effects and cell death. We assessed hippocampal BBB integrity in vivo by evaluating astrocyte activation and the expression of the endothelial tight and adherens junctions proteins. From 1 h to 7 days post-rGO-PEG systemic injection, a notable and progressive down-regulation of protein markers of astrocytes (GFAP, connexin-43), the endothelial tight (occludin), and adherens (ß-catenin) junctions and basal lamina (laminin) were observed. The formation of intracellular reactive oxygen species demonstrated by increases in the enzymatic antioxidant system in the PEGylated rGO samples was indicative of oxidative stress-mediated damage. Under the experimental conditions and design of the present study the PEGylation of rGO did not improve interaction with components of the blood-brain barrier. In contrast, the attachment of PEG to rGO induced deleterious effects in comparison with the effects caused by non-PEGylated rGO.