Effects of vitamin E on the toxicity of oxidized LDL on endothelial cells in vitro in smokers vs nonsmokers on diets rich in fish

• Published in: European journal of clinical nutrition 2005-11, Vol.59 (11), p.1282-1290
• Main Authors: Seppo, L, Lahteenmaki, T, Tikkanen, M.J, Vanhanen, H, Korpela, R, Vapaatalo, H
• Format: Article
• Language: English
• Subjects: Adult; Antioxidants - pharmacology; Biocompatibility; Biological and medical sciences; blood lipids; blood plasma; Cell culture; Cells; Cells, Cultured - drug effects; Clinical Nutrition; Comparative studies; Copper sulfate; Cytotoxicity; Diet; Diet - methods; Dietary Supplements; Endothelial cells; Endothelium, Vascular - drug effects; Endothelium, Vascular - metabolism; Epidemiology; Epoprostenol - blood; Epoprostenol - metabolism; Fish; Fish diets; Fish Oils - metabolism; Humans; In Vitro Techniques; Incubation; Internal Medicine; Lag phase; Lipids - blood; Lipoproteins, LDL - adverse effects; Lipoproteins, LDL - blood; Lipoproteins, LDL - metabolism; Lipoproteins, LDL - toxicity; Low density lipoprotein; Male; Medical sciences; Medicine; Medicine & Public Health; men; Metabolic Diseases; Middle Aged; original-communication; Oxidation; Oxidation-Reduction - drug effects; Pharmacology; Pilot Projects; Prostacyclin; Public Health; Reference Values; seafoods; Smoking; smoking (habit); Smoking - adverse effects; Smoking - metabolism; Tocopherol; Toxicity; Trolox; Vitamin E; Vitamin E - pharmacology; vitamin supplements; water-soluble vitamins
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1602241

Objective: To clarify whether supplementation of vitamin E can alter the low density lipoprotein (LDL) oxidation properties and thereby affect endothelial cell function and prostacyclin production in smokers compared to nonsmokers on diets rich in fish in a pilot study. Design: The LDL of six smokers and six nonsmokers on habitual high fish diet was isolated before and after an 8-week supplementation of vitamin E (800 IU/day). LDL was oxidized by incubation with CuSO4. Cytotoxicity of LDL oxidized to different degrees on endothelial cells was investigated in vitro in these two groups. Setting: Helsinki University Central Hospital; Institute of Biomedicine, Pharmacology, University of Helsinki. Results: At baseline, the rate of oxidation was higher in nonsmokers than in smokers. The lag phase increased significantly after the supplementation of vitamin E both in smokers and nonsmokers. Native LDL dose dependently tended to reduce the viability of endothelial cells in vitro more markedly when isolated from smokers than from nonsmokers. Vitamin E supplementation had no beneficial effect on the cytotoxicity of oxidized LDLs in endothelial cell culture. On the other hand, simultaneous administration of Trolox, the water-soluble analogue of vitamin E, attenuated the LDL cytotoxicity on endothelial cells. The vitamin E supplementation to LDL donors attenuated the increase in prostacyclin production both in smokers and nonsmokers. Conclusion: Supplementation of LDL donors (healthy male volunteers on habitual fish diet) with vitamin E increased the lag phase of LDL oxidation, but, on the other hand, did not influence in vitro cytotoxicity of LDL, or prostacyclin production.