The Health Benefits of Tocotrienols
a-Tocotrienol has been shown to be 40 to 60 times more potent than a-tocopherol in preventing lipid peroxidation and 6.5 times better at defending cytochrome P-450 against oxidative damage. The efficiency of a-tocotrienol in scavenging peroxyl radicals in liposomes is 1.5 fold increased over a-tocopherol. (Serbinova E.,L Packer, et al. Free radical recycling and intermembrane mobility in the antioxidant properties of alpha-tocopherol and alpha-tocotrienol. Radical Biology and Medicine, 1991;10:263-275)
d-Tocotrienol is the most powerful antioxidant of the entire vitamin E family in terms of quenching and scavenging free radicals. The superlative effect of d-tocotrienol is thought to be due to its molecular structure, which is uniformly distributed in cell membranes. This provides greater recycling activity and more effective collusion with free radicals. (Packer L, Weber SU, Rimbach G. Molecular aspects of alpha-tocotrienol antioxidant action and cell signaling. J Nutr 2001 Feb;131(2):369s-73S)
2-1. Cholesterol reduction
Tocopherols have virtually no cholesterol-lowering ability, but tocotrienols, specifically g-tocotrienol and d-tocotrienol, have been shown to inhibit the manufacture of cholesterol within the liver. (Pearce BC, Parker RA, Deason ME, Qureshi AA, Wright JJ. Hycholesterolemic activity of synthetic and natural tocotrienols. J Med Chem 1992;35:526-541 and 3595-606)
The combination of statin drug and tocotrienol creates synergistic effects in lowering total cholesterol and LDL cholesterol (20% and 25% respectively) in hypercholesterolemic subjects. (Qureshi AA, Sami SA, Salser WA, Khan FA. Synergistic effect of tocotrienol-rich fraction (TRF 25) of rice bran and lovastatin on lipid parameters in hypercholesterolemic humans. J Nutr Biochem. 2001 Jun;12(6):318-329)
2-2. Reduce platelet aggregation
As an anti-thrombic agent, tocotrienol has been shown to decrease platelet aggregation activity. d-tocotrienol is the most effective form of vitamin E in reducing the endothelial expression of adhesion molecules and adhesion to monocytes, thus reducing the risk of developing atherosclerotic plaque. (Theriault A, Chao JT, Gapor A, et al. Tocotrienol is the most effective vitamin E for reducing endothelial expression of adhesion molecules and adhesion to monocytes. Atherosclerosis 2002;160:21-30)
2-3. Reversing Artherosclerosis
One of the most striking discoveries in tocotrienols research is their ability to clear atherosclerotic blockages (stenosis) in the carotid artery, potentially reducing the risk of stroke.
Medical research suggested that patients with confirmed carotid atherosclerosis who consumed approximately 240mg of tocotrienols per day for 18-36 months had a decreased amount of cholesterol laden plaque in their carotid artery, while those receiving the placebo experienced an overall worsening of the disease. (Tomeo AC, Geller M, Watkins TR, Gapor A, Bierenbaum ML. Antioxidant effects of tocotrienols in patients with hyperlipidemia and carotid stenosis- 2 year experience.Lipid 1995 Dec;30(12):1179-83) (Kooyenga DK, Geller M, Watkins TR, Gapor A, and Bierenbaum M.Benefit of tocotrienols in patients with carotid stenosis over three years. Proc16th Inti congress on Nutr, Montreal Canada, 1997.)
2-4. Prevention of high blood pressure
Animal studies indicated that LLU-alpha is a metabolite of g-tocotrienol and is able to control the release of excess water (Wechter WJ, Kantoci D, Murray ED Jr, D’Amico DC, Jung ME, Wang WH. A new endogenous natriuretic factor : LLU-alpha. Proc Natl Acad Sci USA 1996 Jun 11;93(12):6002-7), thereby reducing high blood pressure and congestive heart failure.
In a study of tocotrienol in spontaneously hypertensive rats, it was demonstrated that treatment with g-tocotrienol prevented the development of age-related hypertension by scavenging free radicals and enhancing the body’s enzymatic antioxidant defense system. (Newaz MA, Nawal NN. Effect of gamma-tocotrienol on blood pressure, lipid peroxidation and total antioxidant status in spontaneously hypertensive rats (SHR). Clin Exp Hypertens 1999 Nov;21(8):1297-313)
Tocotrienols possess the ability to stimulate the selective destruction of cancer cells through programmed cell death (apoptosis) in order to reduce cancer cell proliferation, while leaving normal cells unaffected. (Kline K, Yu W, Sanders BG. Vitamin E : mechanisms of action as tumor cell growth inhibitors. J Nutr 2001 Jan; 131(1):161S-163S)
In vitro (cell culture) and in vivo (animal) studies concerning the effects of tocotrienols on cancer cells showed that tocotrienols had greater effects than tocopherols on inhibition of cancer cell growth. Studies have shown that tocotrienols are effective in preventing the proliferation of both estrogen responsive (MCF7,ZR-75-1) and estrogen non-responsive (MDA-MB-435) human breast cancer cells. (Nesaretnam K, Guthrie N, Chambers AF, Carroll KK. Effect Of tocotrienols on the growth of a human breast cancer cell line in culture.Lipids 1995 Dec;30(12):1139-43) (Nesasretnam K, Stephen R, Dils R, Darbre P. Tocotrienol inhibits the growth of human breast cancer cells irrespective of estrogen receptor status. Lipids 1998 May;33(5):461-9) (Nesaretnam K, Dorasamy S, Darbre PD. Tocotrienols inhibit growth of ZR-75-1 breast cancer cells. Int J Food Sci Nutr 2000;51 Suppl:S95-103)
Researchers have also demonstrated that g-tocotrienol is a more effective inhibitor of breast cancer cells than tamoxifen.
Researchers have determined that tocotrienols crosses the blood-brain barrier, and are potent protectors of neuron cells that may destroyed through stroke and other neurodegenerative diseases.
In a study of mouse hippocampal HT4 cells, tocotrienols from palm oil were more effective than tocopherols in preventing glutamate-induced cell death. (Chandan K. Sen, Savita Khanna, Sashwati Roy, and Lester Packer. Molecular Basis of Vitamin E Action J Biol Chem 2000, Vol.275, Issue 17,13049-13055) It is believed that tocotrienols are more uniformly distributed in the membrane bilayer, more efficiently recycled from its corresponding chromanoxyl radical form, and more able to strongly disorder membrane lipids, allowing for a better interaction of chromanols with lipid radicals.
Tocotrienols penetrate rapidly through skin, and topical application is an efficient means to enrich the skin with vitamin E. (Traber M. G., Rallis M., Podda M., Weber C., Maibach H.I., Packer L. Penetration and distribution of a-tocopherol, a- or g-tocotrienols applied individually onto murine skin. Lipids 1998;33:87-91) When taken orally or applied topically, tocotrienols significantly reduce the damaging effects of free radicals on the skin and help to maintain or restore a healthy skin barrier. (Thiele JJ, Schroeter C, Hsieh SN, Podda M, Packer L.The antioxidant network of the stratum corneum. Curr Probl Dermatol. 2001;29:26-42)
At the Life Science Research Center in Japan, palm-derived tocotrienols have demonstrated that tocotrienols, not alpha-tocopherol, significantly extends the average life span of organisms. (Adachi H, Ishii N. Effects of tocotrienols on life span and protein carbonylation in Caenorhabditis elegans. J Gerontol A Biol Sci Med Sci 2000 Jun;55(6):B280-5) The nematodes exposed to tocotrienols enriched (80ug/ml) growth medium lived 19% longer than the control group. A lower concentration (8ug/ml) of tocotrienols extended average lifespan by 9%. a-Tocopherol had no effect on lifespan.
This indicates that tocotrienols are more than simply ‘chain-breaking, antioxidants, and are in fact capable of repairing damage that has already occurred.