Dr. Muhammad Torequl Islam :
Vitamin E (vit E) (other names: alpha-tocopherol, alpha-tocopherol, tocotrienol, 5,7,8 trimethyl-tocotrienol), a group of eight fat soluble compounds, including four tocopherols and four tocotrienols. Vit E is a strong antioxidant that protects cell membranes from oxidative stress caused by reactive oxygen/nitrogen species. Although vit E acetate is evident to cause lung disease, but vit E plays many important functions in our immune system, including cell-mediated microorganism destruction and antibody production.
Generally, deficiency in healthy adults is rare, even among people living on relatively poor diets, both T- and B-cell functions are impaired by vit E deficiency. While immune cells are particularly enriched by vit E because of their high polyunsaturated fatty acid content, therefore, they are at high risk of oxidative damage as besides immunomodulatory effects, vit E at high levels may cause carcinogenesis due to its pro-oxidative effect.
However, newborn infants may be deficient in this vitamin as their serum levels depend on the body vit E levels of their mothers. Deficiency of this vitamin occurs in peoples having an abnormality in dietary fat absorption or metabolism. Mutations of genes encoding to alpha-tocopherol transfer protein may result deficiency of this vitamin, which is associated with the progressive neurodegenerative disorder (e.g., dementia) in certain people. Vit E deficiency can impair immunological functions and cause nerve problems, peripheral neuropathy, myopathies, retinopathy and cardiovascular diseases (e.g., atherosclerosis, heart attacks, coronary heart disease, ischaemic stroke, haemorrhagic stroke, pulmonary embolism). Although the contribution of its deficiency in cancer is still controversial, but some studies indicate that its deficiency may associate with some cancers (e.g., kidney, bladder, lung, prostate, colorectal). It can be used for reducing the risk of stillbirth, neonatal death, preterm birth, preeclampsia and to treat nonalcoholic fatty liver disease, Parkinson’s disease, wound, scar tissue, cystic fibrosis, breast disease, leg muscle pains, sexual dysfunction, and athletic malperformance.
Dietary supplements containing more than 300 mg/day may interact with some drugs, including aspirin, warfarin, tamoxifen and cyclosporine A. Major side effects of high dose of this vitamin includes – fatigue, weakness, nausea, blurred vision, gas and diarrhea. Vit E is evident to increase the effects of oral anti-coagulants, which may increase clotting and bleeding time. It should be mentioned that large doses of this vitamin may decrease serum vitamin A reserves in human.
Supplementation of vit E significantly enhances both cell mediated and humoral immune functions in humans, especially in the elderly. Deficiency of this vitamin boosted the myocardial injury in mice infected by the RNA virus, coxsackievirus B3. Moreover, a decrease in this vitamin status significantly increased the risk of bovine coronavirus infection in calves. Vit E widens the blood vessels and helps to keep clots from forming in them. Vit E plus other antioxidants and some minerals (e.g., zinc, copper) resulted good outcomes in vision loss. It should be mentioned that high mortality rates in novel coronavirus disease 2019 (COVID-19) have been seen in patients with cardiovascular diseases. Therefore, correction of vit E deficiency during the pandemic COVID-19 should be taken into account.
(Dr. Muhammad Torequl Islam is Assistant Professor, Department of Pharmacy, Life Science Faculty, Bangabandhu Sheikh Mujibur Rahman Science and Technology University.
E-mail: [email protected])
