Top Brand Vitamins at Wholesale Cost

Search products:
Vitamins & Supplements | Weight Management | Herbs | Sports Nutrition | Bath & Beauty


NSI Mega EFA® Omega-3 EPA & DHA -- 2126 mg - 240 Softgels

NSI Mega EFA® Omega-3 EPA & DHA72% off
Retail price:
$79.99

Our price:
$21.99


View details for NSI Mega EFA® Omega-3 EPA & DHA

NSI Probiotic 15 - 35 -- 120 Vegetarian Capsules

NSI Probiotic 15 - 3560% off
Retail price:
$69.99

Our price:
$27.77


View details for NSI Probiotic 15 - 35

NSI Synergy Once Daily Multi-Vitamin Version 3 -- 60 Capsules

NSI Synergy Once Daily Multi-Vitamin Version 350% off
Retail price:
$39.99

Our price:
$19.99


View details for NSI Synergy Once Daily Multi-Vitamin Version 3

NSI Hyaluronic Acid with BioCell Collagen II® -- 100 mg - 240 Capsules

NSI Hyaluronic Acid with BioCell Collagen II®50% off
Retail price:
$79.99

Our price:
$39.99


View details for NSI Hyaluronic Acid with BioCell Collagen II®

NSI ToCoQ10 -- 100 mg - 120 Softgels

NSI ToCoQ1081% off
Retail price:
$108.99

Our price:
$19.99


View details for NSI ToCoQ10

« Give Your Health a Boost with Pure Cranberry Juice | Main | NSI Brand for Purity, Strength and Wellbeing »

February 10, 2009

Comments

Bart

Pharmacokinetic and safety profile of trans-resveratrol in a rising multiple-dose study in healthy volunteers: This was a double-blind, randomised, placebo-controlled study to investigate the pharmacokinetics and safety of trans-resveratrol. In four groups of ten healthy adult subjects (five males and five females), two subjects were randomized to receive placebo and eight subjects to receive trans-resveratrol 25, 50, 100 or 150 mg, six times/day, for thirteen doses. Peak plasma concentrations of trans-resveratrol were reached at 0.8-1.5 h postdose. Following the 13th dose of trans-resveratrol 25, 50, 100 and 150 mg, mean peak plasma concentration (C(max)) was 3.89, 7.39, 23.1 and 63.8 ng/mL and mean area under the plasma concentration-time curve (AUC(0-tau)) was 3.1, 11.2, 33.0 and 78.9 ng.h/mL. Interindividual variability was high, with coefficients of variation >40%. Trans-resveratrol half-life was 1-3 h following single-doses and 2-5 h following repeated dosing. Trough (C(min)) concentrations were less, not double equals1 ng/mL following 25 and 50 mg, 3 ng/mL following 100 mg and < 10 ng/mL following 150 mg. Trans-resveratrol pharmacokinetics showed circadian variation. Adverse events were mild in severity and similar between all groups. In conclusion, repeated administration was well-tolerated but produced relatively low plasma concentrations of trans-resveratrol, despite the high doses and short dosing interval used. Bioavailability was higher after morning administration.

In previous studies the same bioavailability problem was showed :

HIGH ABSORPTION BUT VERY LOW BIOAVAILABILITY OF ORAL RESVERATROL IN HUMANS

Department of Cell and Molecular Pharmacology and Experimental Therapeutics (T.W., J.E.O., U.K.W.) and Digestive Disease Center (M.H.D.), Medical University of South Carolina, Charleston, South Carolina; and Amgen, Inc., Thousand Oaks, California (F.H.)

The dietary polyphenol resveratrol has been shown to have chemopreventive activity against cardiovascular disease and a variety of cancers in model systems, but it is not clear whether the drug reaches the proposed sites of action in vivo after oral ingestion, especially in humans. In this study, we examined the absorption, bioavailability, and metabolism of 14C-resveratrol after oral and i.v. doses in six human volunteers. The absorption of a dietary relevant 25-mg oral dose was at least 70%, with peak plasma levels of resveratrol and metabolites of 491 ± 90 ng/ml (about 2 µM) and a plasma half-life of 9.2 ± 0.6 h. However, only trace amounts of unchanged resveratrol (<5 ng/ml) could be detected in plasma. Most of the oral dose was recovered in urine, and liquid chromatography/mass spectrometry analysis identified three metabolic pathways, i.e., sulfate and glucuronic acid conjugation of the phenolic groups and, interestingly, hydrogenation of the aliphatic double bond, the latter likely produced by the intestinal microflora. Extremely rapid sulfate conjugation by the intestine/liver appears to be the rate-limiting step in resveratrol's bioavailability. Although the systemic bioavailability of resveratrol is very low, accumulation of resveratrol in epithelial cells along the aerodigestive tract and potentially active resveratrol metabolites may still produce cancer-preventive and other effects.

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been saved. Comments are moderated and will not appear until approved by the author. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Comments are moderated, and will not appear until the author has approved them.

Copyright ©2005 Vitacost.com. All rights reserved • Designated trademarks and brands are the property of their respective owners.