Lipid peroxidation in rat tissue slices: Effect of dietary vitamin E, corn oil‐lard and menhaden oil

Abstract

Rats were fed for 5 weeks either 10% (w/w) menhaden oil (MO) or a 10% corn oil-lard (COL) mixture (1:1) in diets with less than or equal to 5 IU or less than or equal to 2 IU/kg vitamin E, respectively, or the same diets supplemented with d-alpha-tocopheryl succinate to a total of 35 and 180 IU vitamin E/kg, respectively. Slices of liver and heart from these rats were used to study lipid peroxidation in vitro. Thiobarbituric acid-reactive substances (TBARS) were measured in the medium after incubation of the slices at 37 degrees C for 1 hr in the absence (uninduced) and presence of 0.5 mM tert-butyl hydroperoxide (induced). The release of TBARS from slices of heart and liver from rats fed either lipid decreased with increasing levels of dietary vitamin E. At the same level of dietary vitamin E, TBARS release was greater for slices of liver and heart from the MO-fed rats than from the COL-fed rats. Application of the TBARS data to a model simulating the experimental conditions showed a good correlation (r = 0.95, p less than 0.001) between experimental and simulated values. Of the 16:0-22:6 fatty acids measured in liver from MO-fed rats, 15.4% was n-6 fatty acids and 29.9% was n-3 fatty acids; in liver from COL-fed rats, the respective values were 37.4% and 3.7%. Liver and kidney vitamin E levels were unaffected by the dietary lipid.(ABSTRACT TRUNCATED AT 250 WORDS)

Technological challenges to assess n-3 polyunsaturated fatty acids from marine oils for nutritional and pharmacological use

“…By eating fish or fish oils we load our phospholipids with EPA and DHA at the expense of their content of arachidonic acid, increasing the susceptibility of lipid membranes to oxidative damage. This effect has been observed in experimental animals by several authors (Mails et al 1990, Garrido et al 1989, Leibovitz et al 1990). Moreover, age appears as an important factor in the development of these susceptibility.…”

The effect of a diet fortified with polyunsaturated fatty acids on the level of selected elements in the myocardium of growing pigs

“…PUFAs, which are not protected from oxidation, may promote lipid peroxidation and degradation of cellular membranes, which can lead to an excessive inflow of Ca into the cell. In the discussed experiment, vitamin E was supplied in considerable amounts, therefore we may suppose that the obtained results were only a consequence of PUFA n-3 activity (Leibovitz et al, 1990) and not of their oxidized derivatives.…”

Role of dietary lipids and butylated hydroxy anisol (BHA) administration on albino rats. Part II. Liver and heart unsaturated fatty acids

“…These results were in agreement with the finding reported by JOHNSON et al [17], who proved that the use of different doses of BHA mixed with lard for six weeks, had no effect on PUFA composition of rats liver. Also, LEIBOVITZ et al [20], revealed that different doses of vitamin E in groups of rats fed the same lipid did not affect the fatty acids of liver composition.…”