ABSTRACT
The immune system is comprised of lymph glands, lymph nodes, thymus gland, spleen, bone marrow, lymphocytes, and molecules such as antibodies and cytokines. It has a vast array of functionally different cells such as T and B lymphocytes, macrophages, neutrophils and mast cells. The ontogenesis of the immune system is comprised of the innate immune cells and the adaptive immune cells, where innate immune cells are the first defense mechanisms to respond to pathogenic environmental factors. There are multiple components of the adaptive immune cells, including immunoglobulins (Igs), T-cell receptors (TCR), and major histocompatibility complex (MHC) responsible for adaptive immunity. However, many elements of both the innate and adaptive immune systems are conserved in our bodies. The adaptive immunity is a type of immunity that develops when a person’s immune cells respond to a pathogen such as microorganism or vaccination. Environmental factors such as pathogenic bacteria or viruses, solar exposure, age, exercise, stress, diet, sleep quality and air pollutants can influence the immune system. There may be marked decline in the immune function due to attack of COVID-19. Most patients with mild COVID-19 develop an appropriate immune response that culminates with viral clearance. However, severe disease manifestations have been linked to lymphopenia and immune hyper-responsiveness leading to cytokine storm. It has been observed that in COVID-19, alveolar macrophages are epigenetically altered after inflammation, leading to long-term lung immune-paralysis. Western diets are known to have adverse effects on the immune function. However, Mediterranean-type diets rich in short-and long-chain polyunsaturated fatty acids (PUFA), vegetables, nuts and fruits, dairy products and fish and red wine, due to high content of vitamins, minerals and flavonoids may be useful in boosting immunity. Moderate physical activity may also cause an extensive increase in numerous and varied lipid super-pathway metabolites, including oxidized derivatives called oxylipins. Emerging evidence suggests that dietary supplements containing flavonoids, carotenoids, coenzyme Q10 (CoQ10), vitamins, minerals and antioxidants modulate gene and protein expression and thereby modify endogenous metabolic pathways, and consequently enhance the immunity. Mediterranean-type diet and multiple bioactive nutrients, fatty acids, amino acids, vitamins and minerals as well as moderate physical activity may be crucial for enhancing immunomodulation.
ABSTRACT
Novel Coronavirus disease 2019 (COVID-19) represents an emergent global health burden that has challenged the health systems worldwide. Since its sudden upsurge in 2019, many COVID-19 patients have exhibited neurological symptoms and complications. Till now, there is no known effective established drug against the highly contagious COVID-19 infection despite the frightening associated mortality rate. This article aims to present the mechanism of action of coronavirus-2 (SARS-CoV-2), the clinical neurological manifestations displayed by COVID-19 patients, and present polyphenols with neuroprotective ability that can offer beneficial effects against COVID-19-mediated neuropathology. Reports from COVID-19 clinical studies, case reports, and other related literature were evaluated for this review. Neurological complications of COVID-19 include anosmia, acute cerebrovascular disease, acute disseminated post-infectious encephalomyelitis, encephalitis, etc. Also, SARS-CoV-2 could be a neurotropic virus455;due to its iolation from cerebrospinal fluid. Multiple neurological damages displayed by COVID-19 patients might be due to hyperinflammation associated with SARS-CoV-2 infections. Resveratrol, kolaviron, quercetin and apigenin are polyphenols with proven anti-inflammatory and therapeutic properties that can extenuate the adverse effects of COVID-19. These polyphenols have been documented to suppress c-Jun N-terminal kinase (JNK), phosphoinositide-3-kinase (PI3-K), extracellular-signal-regulated kinase (ERK), nuclear factor kappa-light-chain-enhancer of activated B-cells (NF-kB) and mitogen-activated protein kinase (MAPK) pathways which are essential in the pathogenesis of COVID-19. They also showed significant inhibitory activities against SARS-CoV-2 proteins. Taken together, these polyphenols may offer neuroprotective benefits against COVID-19 mediated neuropathology via modulation of the pathogenic pathways.
ABSTRACT
OBJECTIVES: The aim of this study was to seek potential natural compounds that can resist COVID-19 using computer virtual screening technology through molecular docking of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) 3CL hydrolytic enzyme (3CLpro) and angiotensin-converting enzyme 2 (ACE2). METHODS: Molecular docking was achieved by using the Autodock Vina software. The natural phytocompounds acting on 3CLpro and ACE2 were then selected from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform. This was followed by speculation on the mechanism of action of phytocompounds. RESULTS: Six potential natural anti-COVID-19 phytocompounds were selected and were evaluated for absorption, distribution, metabolism and excretion (ADME) and Lipinski rules. The content of the six phytocompounds in various fruits and vegetables was determined via a literature search. Red wine, Chinese hawthorn, and blackberry were recommended as supplements because they contained antiviral phytocompounds. CONCLUSION: Red wine, Chinese hawthorn, and blackberry show promise for resisting COVID-19 and are thus recommended as supplements to prevent the infection of COVID-19 during its outbreak period.