A Suggested Method for the Prediction of the Oxidation Resistance of Low Density Lipoprotein by Determination of the Lag Time

Abstract

A simple clinical blood test, which measures the total antioxidant status of Low Density Lipoprotein (LDL) and therefore its vulnerability to oxidative stress is suggested, and as a first stage this was tried on a small sample of eight healthy adult males.

The body's natural defence and repair systems try to handle all free radicals, but these systems are not hundred percent effective. Thereby, the role of antioxidants (particularly natural antioxidants) becomes evident and vitamins such as Vitamin C, Vitamin E, and compounds like beta-carotene are under especially extensive study. Vitamin C is the most abundant water-soluble antioxidant acting in extracellular fluid, while Vitamin E is the most abundant fat-soluble antioxidant, and it protects the polyunsaturated fatty acids within the LDL from oxidation and helps to prevent the process of atherogenesis.

The determination of ‘lag-phase’ during continuous monitoring of oxidation of LDL in vitro is a convenient and objective procedure for determining the susceptibility of LDL from different donors towards oxidation as well as of pro- and anti-oxidants. The Lag-time for LDL samples, obtained from eight healthy adult males was found to be between 40–50 minutes. The measurement of this Lag-phase could be a highly promising routine method for measuring the total antioxidant status of LDL.

Keywords

Antioxidants LDL Oxidation Lag-time

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References

Whitney

E.N.

Rolfes

S.R.

Cataldo

C.B.

(1998). Antioxidant nutrients and non-nutrients in disease prevention. In: Understanding Normal and Clinical Nutrition. 7th Edition. New York, West Publishing Company, 400–407.

Burton

G.W.

Traber

M.G.

(1990). Vitamin E: Antioxidant activity, biokinetics and bioavailability. Ann. Rev. Nutr., 10, 357–382.

Packer

(1990). Protective role of Vitamin E in biological systems. Am. J. Clint. Nutr., 53, 1050S–1055S.

Tangney

C.C.

(1997). Vitamin E and cardiovascular disease. Nutrition Today, Jan/Feb, 13–22.

Esterbauer

et al. (1989). Continuous monitoring of in vitro oxidation of human low-density lipoprotein. Free Rad. Res. Comm., 6, 67–75.

Gatto

L.M.

Samman

(1995). The effect of zinc supplementation on plasma lipids and LDL oxidation in males. Free Rad. Biol. Med, 19, 517–521.

Markwell

M.A.

et al. (1978). A modification of the Lowry procedure to simplify protein determination in membrane and lipoprotein samples. Anal. Biochem., 87, 206–210.

Esterbauer

et al. (1992). The role of lipid peroxidation and antioxidants in oxidative modification of LDL. Free Rad Biol. Med., 13, 341–390.

Abbey

Nestel

P.J.

Baghurst

P.A.

(1993). Antioxidant vitamins and low-density lipoprotein oxidation. Am. J. Clin. Nutr., 58, 525–532.

10.

Wilcox

J.G.

et al. (1997). Cardioprotective effects of individual conjugated equine-estrogens through their possible modulation of insulin resistance and oxidation of low-density lipoprotein. Fertil. Steril., 67, 57–62.

11.

Kritchevsky

(1992). Antioxidant vitamins in the prevention of cardiovascular disease. Nutrition Today, Jan/Feb, 30–33.

12.

Riemersma

R.A.

(1994). Epidemiology and the role of antioxidants in preventing coronary heart disease: a brief over-view. Proc. Nut. Soc. 53, 59–65.