Delta-tocotrienol - The 21st Century Vitamin E?

[Guest guest]

1:6:2003

Delta-tocotrienol - The 21st Century Vitamin E?

 

Introduction

 

The vitamin E family consists of four tocopherols and four

tocotrienols each designated as alpha, beta, gamma, or delta based

upon slight differences in attached molecules. Of these naturally

occurring vitamin E compounds, alpha-tocopherol (alpha T) has

emerged has the most potent of these compounds in terms of vitamin E

activity. However, newer information indicates that for other

activities including antioxidant, cholesterol lowering, and anti-

cancer effects that the tocotrienols (T3s), especially delta-

tocotrienol (delta T3) exert more profound effects.1 So, while in

terms of vitamin E activity the order of potency would be:

 

alpha T > beta T > gamma T > alpha T3 > delta T > gamma T3 > delta T3

 

The order of potency for acting as an antioxidant, cholesterol-

lowering agent, and in cancer prevention may be just the opposite:

 

delta T3 > gamma T3 > delta T > gamma T > alpha T3 > beta T > alpha

T

 

What is the difference between a tocopherol and a tocotrienol?

 

The difference is that the tocotrienol has 3 double bonds within the

main body of the molecule. Just like as in polyunsaturated oils, the

presence of these double bonds give the tocotrienols greater

fluidity and make it much easier for the body to incorporate them

into cell membranes, especially delta-tocotrienol.2 Differences

between the various individual members of the tocopherol and

tocotrienol family are due to different molecules found at the R1,

R2, and R3 positions.

 

 

 

Compound R1 R2 R3

alpha-tocopherol

alpha-tocotrienol CH3 CH3 CH3

beta-tocopherol

beta-tocotrienol

CH3 H CH3

gamma-tocopherol

gamma-tocotrienol H CH3 CH3

delta-tocopherol

delta-tocotrienol H H CH3

 

What are the health benefits of tocotrienols?

 

In comparing the health benefits of the tocopherols vs. the

tocotrienols I will limit the discussion to the following areas:

antioxidant effects, anticancer effects, cholesterol lowering

effects, and effects on other aspects of cardiovascular disease. Do

not misunderstand me. I am NOT saying that vitamin E (alpha-

tocopherol) is not important. It possesses the greatest

physiological vitamin E activity and is an important component of

any nutritional supplementation plan. However, when some specific or

additional support is needed then the tocotrienols, especially delta-

tocotrienol, appears to offer even greater benefit.

 

Antioxidant activity

 

While vitamin E is generally regarded as the most important fat-

soluble antioxidant, alpha-tocotrienol has been shown to be 40 to 60

times more potent than alpha-tocopherol in the prevention of lipid

peroxidation. Even more potent is delta-tocotrienol - by far the

most powerful antioxidant of the entire vitamin E family.

Tocotrienols may prove more valuable in protecting the interior cell

membranes, such as those that surround the cell nucleus and

mitochondria, because of their greater ease in being incorporated

into cellular membranes.1,2

 

Cholesterol reduction

 

Tocopherols have virtually no cholesterol-lowering activity, but

numerous clinical studies have shown tocotrienols, specifically

gamma-tocotrienol and delta-tocotrienol, to inhibit the manufacture

of cholesterol within the liver.3 Specifically, these tocotrienols

inhibit the liver enzyme HMG-CoA reductase - the same enzyme

inhibited by the statin drugs and red yeast rice. Although clinical

studies have yielded inconsistent results with tocotrienol

preparations in lowering cholesterol, that is easily explained by

taking a closer look at the types of tocotrienols used in the study

and their dosage.

 

Commercial sources of tocotrienols

 

There are three commercial sources of tocotrienols - rice bran oil,

palm oil, and annatto bean (DeltaGOLD™). It is important to

understand the shortcomings of the first two to truly appreciate the

differences in the results achieved in the clinical trials on

lowering cholesterol.

 

Ratios of tocopherols and tocotrienols in commercial sources

 

Rice Palm DeltaGOLD™

Tocopherols

Alpha-tocopherol 41.7% 21.8% 0%

Other tocopherols 6.7% 0% 0%

Tocotrienols

Alpha-tocotrienol < 2% 22.1% 0%

Gamma-tocotrienol 51.6% 45.7% 10%

Delta-tocotrienol 0% 10.4% 90%

 

There are a couple of very important points to make when looking at

the results:

 

The higher the level of tocopherols in a tocotrienol preparation,

the less effective the product is at lowering cholesterol levels.

Tocopherols block the ability of delta- and gamma-tocotrienol to

inhibit HMG-CoA reductase.4

Proper dosage is also important. Since tocotrienols can be converted

to alpha-tocopherol in the body, taking too high a dosage of

tocotrienols actually reduces their ability to lower cholesterol

levels.5 Dosages of 25 to 100 mg may prove more effective than

dosages of 200 mg or more daily.

When these factors are taken into consideration it is easy to

explain why certain studies were positive and others were

negative.1,5-9 Tocotrienol concentrates with higher amounts of gamma-

and delta-tocotrienols, and lower alpha-tocopherol have produced

reductions of total cholesterol of 15% and an 8% reduction in LDL

levels within the first four weeks of use.

 

Additional cardiovascular benefits

 

Tocotrienols have been shown to exert additional benefits to the

cardiovascular system including an ability to decrease in the amount

of cholesterol plaque in arteries, lower the level of the extremely

damaging lipoprotein (a), prevent the aggregation of platelets, and

inhibit the expression of cellular adhesion molecules.1,10 All of

these factors are extremely important in the development and

progression of atherosclerotic plaque. Delta-tocotrienol has been

shown to be the most active of the tocotrienols.

 

Summary of benefits of delta-tocotrienol

 

Most powerful antioxidant of the vitamin E family.

The most potent tocotrienol to activate anticancer effects.

More effective at accumulating in cells compared to other

tocotrienols.

Most effective member of the vitamin E for reducing endothelial

expression of adhesion molecules, thereby preventing the

accumulation of inflammatory cells within the arterial wall.

Most potent tocotrienol in inducing apoptosis (cell deaths) of human

breast cancer cells. Delta-tocotrienol was twice as potent as of

gamma-tocotrienol.

Inhibits the excessive aggregation of blood platelets much more

effectively than vitamin E or other tocotrienols.

Anticancer effects of tocotrienols

 

The anticancer effects of tocotrienols have garnered a lot of

attention. In addition to their important antioxidant effects,

several other mechanisms have been proposed. For example, one of the

innate protectors against cancer is a process known as " apoptosis. "

Basically, apoptosis is an encoded suicide program designed to

protect cells from becoming cancerous. When this process does not

work cancer develops. Tocotrienols are effective promoters of

apoptosis with delta-tocotrienol being twice as potent as gamma-

tocotrienol.11 Another anticancer mechanism involves inhibiting

enzymes within cancer cells that stimulate them to replicate. Gamma-

tocotrienols was shown to be three times more potent in inhibiting

growth of human breast cancer cultured cells than chemotherapy drug

tamoxifen.12

 

What are the dosage, drug interactions, and safety information for

tocotrienols?

The effectiveness of tocotrienols for some specific indications

requires using tocopherol-free, high delta-tocotrienol products at a

proper dosage. For example, for lowering cholesterol, utilize the

90% delta-tocotrienol preparation and begin with a dosage of 50 mg

tocotrienols. Recheck cholesterol levels in four to six weeks and

alter dosage accordingly. If cholesterol levels drop into the normal

range, the dosage can be reduced. If cholesterol levels do not

change enough, the dosage can be increased to 100 mg per day. For

best results take the tocotrienols with food and at least one hour

away from any vitamin E.

 

Tocotrienols are extremely safe and no side effects have been

reported.13 Given the effects on platelet aggregation, you will need

to inform your physician of their use if you are going in for

surgery, or taking the blood thinning drug Coumadin® (warfarin) or

anti-platelet drugs like Ticlid® (ticlopidine).

 

Tocotrienols enhance the cholesterol-lowering effects of statin

drugs and, presumably, red yeast rice extract.7

 

 

 

References:

 

Theriault A, Chao JT, Wang Q, Gapor A, Adeli K. Tocotrienol: a

review of its therapeutic potential. Clin Biochem 1999;32:309-19.

Yap SP, Yuen KH, Wong JW. Pharmacokinetics and bioavailability of

alpha-, gamma- and delta-tocotrienols under different food status. J

Pharm Pharmacol 2001;53:67-71.

Pearce BC, Parker RA, Deason ME, Qureshi AA, Wright JJ.

Hypocholesterolemic activity of synthetic and natural tocotrienols.

J Med Chem 1992;35: 526-541 and 3595-606.

Qureshi AA, Pearce BC, Nor RM, et al. Dietary alpha-tocopherol

attenuates the impact of gamma-tocotrienol on hepatic 3-hydroxy-3-

methylglutaryl coenzyme A reductase activity in chickens. J Nutr

1996;126:389-94.

Qureshi AA, Sami SA, Salser WA, Khan FA. Dose-dependent suppression

of serum cholesterol by tocotrienol-rich fraction (TRF25) of rice

bran in hypercholesterolemic humans. Atherosclerosis 2002;161:199-

207.

Mustad VA, Smith CA, Ruey PP, Edens NK, DeMichele SJ.

Supplementation with 3 compositionally different tocotrienol

supplements does not improve cardiovascular disease risk factors in

men and women with hypercholesterolemia. Am J Clin Nutr 2002;76:1237-

43.

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;12:318-329.

Mensink RP, van Houwelingen AC, Kromhout D, Hornstra G. A vitamin E

concentrate rich in tocotrienols had no effect on serum lipids,

lipoproteins, or platelet function in men with mildly elevated serum

lipid concentrations. Am J Clin Nutr 1999;69:213-9.

Qureshi AA, Bradlow BA, Brace L, et al. Response of

hypercholesterolemic subjects to administration of tocotrienols.

Lipids 1995;30:1171-7.

Theriault A, Chao JT, Gapor A, et al. Tocotrienol is the most

effective vitamin E

 

www.doctormurray.com