Clinical trial supports cardiovascular benefits of annatto tocotrienols
Scientists from the University of Missouri – Kansas City report that tocotrienol doses ranging from 125 – 750mg/day combined with the healthy diet decreased lipid levels significantly after only 4 weeks, with 250mg/day found to be the optimal dose.
The higher doses of annatto tocotrienol, which is mainly composed of delta-tocotrienol, did not reduce lipid levels, said the researchers. However, throughout the 30-week study period no adverse events were reported for any of the dosages, reflecting the safety of the supplement, according to clinical findings published in the British Journal of Medicine and Medical Research.
“The results confirm that consumption of delta-tocotrienol plus AHA Step-1 diet causes significant reduction in serum lipid parameters and several cytokines at a low optimal dose,” concluded the researchers, led by Dr Asaf Qureshi, a pioneer in vitamin E tocotrienol research.
Vitamin E is a family of eight separate but related molecules: four tocopherols (alpha, beta, gamma, delta) and four tocotrienols (alpha, beta, gamma, delta). While alpha-tocopherol is found in most multivitamins and is supplemented in foods, a growing base of evidence suggests that this popular vitamin E interferes with the uptake and function of tocotrienols. Tocotrienols are derived from three major sources, including rice, palm and annatto. Annatto is the only tocopherol-free source of tocotrienols.
The current study used the DeltaGold annatto tocotrienol ingredient supplied by American River Nutrition, and typically contains about 90% delta- and 10% gamma-tocotrienol.
The potential cholesterol lowering effects of tocotrienols are reported to involve post-transcriptional suppression of HMGR (3-hydroxy-3-methyl-glutaryl-CoA reductase - the enzyme/protein responsible for the body’s cholesterol production) via controlled degradation of the reductase protein. This protein degradation is reportedly only seen with delta- and gamma-tocotrienol.
In the current study, researchers tested the effects of annatto tocotrienol doses ranging from 125 – 750mg per day on 31 people with elevated cholesterol levels. Results showed that after only 4 weeks, the optimum daily dose of 250mg decreased total cholesterol by 15%, LDL cholesterol by 18%, and triglycerides by 14%.
Furthermore, cytokines associated with cardiovascular disease and their gene expression, including TNF-alpha, IL-2, IL-4, IL-6, and IL-8, were down-regulated 39-64%. Selected microRNAs that are typically down-regulated in hypercholesterolemic individuals were up-regulated by tocotrienol treatment, suggesting a beneficial effect on these biomarkers.
A lack of lipid-lowering effects with the smaller 125mg daily dose may have been remedied by extending the treatment period to 8 weeks, said the researchers. Higher doses of 500mg and 750mg, however, did not decrease lipids compared to baseline. None of the participants reported any adverse events throughout the course of the study, indicating the supplement’s safety across the range of dosages utilized.
Commenting on the research, Dr. Barrie Tan, president of American River Nutrition Inc. said: “Dr. Asaf Qureshi has pioneered tocotrienol research for nearly 35 years. His work continues to yield critical clinical studies, particularly in connection to delta- and gamma-tocotrienols.”
Source: British Journal of Medicine & Medical Research
Published online ahead of print, doi: 10.9734/BJMMR/2015/13820
“Dose-dependent modulation of lipid parameters, cytokines and RNA by delta-tocotrienol in hypercholesterolemic subjects restricted to AHA Step-1 diet”
Authors: A.A. Qureshi, D.A. Khan, W. Mahjabeen, N. Qureshi