Oxidative stress and lipid per-oxidation with repeatedly heated mix vegetable oils in different doses in comparison with single time heated vegetable oils.

Cardiovascular diseases and cancer are the leading cause of death worldwide, changed lifestyle and eating habits are the major contributing factors. Daily consumption cooking oils is one of the nutritional sources in today's life. Oils are available in market in the blend of two or more oils to get the maximum health benefits. There are number of factors which decide the pathogenic or protective effects of these oils, like fatty acids(FAs) composition, duration and extent of thermal exposure, daily intake and consumption duration. While processing the food cooking oils are thermally oxidized, that exert deleterious health effects, when taken for long time. The present study designed to evaluate the lipid peroxidation and level of oxidative stress in rabbits treated with repeatedly heated mix vegetable oils, in low (L-RHMVO) and high doses (H-RHMVO) in comparison with single time heated olive (STH-OO), canola (STH-CO), sunflower (STH-SO) oils individually and in mixture (STH-MVO) collected from Karachi (Pakistan).Six groups of animals treated with all these processed oils for 16 weeks along with normal diet .Control group was kept on normal rabbit diet. Animal body and organ weight was recorded. Blood samples were collected to measure plasma Malondialdehyde (MDA), Homocysteine(H-Cys), Creatine phosphokinase (CPK), Lactate dehydrogenase (LDH),C-reactive protein (CRP) and lipid profile (TGs, Total-cholesterol, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol).Statistically highly significant (p<0.005) increased body and organ weight along with Total-cholesterol, TGs, LDL-cholesterol, VDLD-Cholesterol, H-Cys, MDA,CPK,LDH & CRP and decreased HDL-cholesterol was found in H-RHMVO and L-RHMVO groups in dose dependent manner compared to control and single time heated oils groups. Among the single time heated oils STH-SO fed animals had significant (p<0.05) increase in lipid periodization and oxidative stress parameters. STH-OO showed least variation from control with significant increase in HDL-cholesterol level. The finding of this study not only confirms health deleterious effect of vegetable oils when used in thermally oxidized condition but also suggests induced-metabolic changes with oxidative stress. So more advance studies simulating real-life exposure to multiple hazardous substances is required.