Re: Re: Question about resveratrol...

[Guest guest]

Hi Diane,

Sorry but I personally don't buy this argument.

Most beneficial drugs you take are metabolized by your body to other forms

such as glucuronides. Some of these circulating forms are actually *more*

bioactive than the parent form. So its possible the resveratrol

metabolites are possibly less or possibly more bioactive/potent.

Unfortunately, synthesizing these metabolites in any meaningful amounts to

do the appropriate studies to see how good they might be is pretty outrageous.

The main fact remains that red wine shows positive health effects.

Something in it (or its metabolites) is " good " for us.

-W

> Scientists question power of resveratrol supplements

>

> 4/22/2004 - Supplements of resveratrol, the compound found in red wine

> that is thought to fight heart disease, is unlikely to have any effect

> on preventing most cancers, said researchers this week.

>

> The antioxidant compound found in grapes, peanuts and several berries

> has been proposed as an explanation for the low incidence of

> cardiovascular disease in wine-drinking southern European countries.

>

> It has also been shown to possess anti-inflammatory and anti-cancer

> activity in cell-based experiments and is currently in clinical trials

> for its ability to treat oral herpes and cancer.

>

> But new research shows, that taken in supplements, the ingredient does

> not reach the circulating blood in sufficient amounts to have

> therapeutic effects.

>

> Dr Walle and colleagues from the Medical University of South

> Carolina gave resveratrol to six healthy adults aged between 23 and

> 29. The chemical was tagged with a radioactive marker known as

> Carbon-14, which allows researchers to later detect it in tissues and

> blood. It was also given intravenously to the volunteers.

>

> They found that the 25 mg doses of resveratrol were very well absorbed

> after oral dosing with most of the dose appearing in the urine in the

> first 12 hours. However, the urine contained resveratrol only as

> sulphate and glucuronic acid conjugates, none as the free, presumably

> active, form.

>

> Likewise, the only blood samples containing free resveratrol were

> those drawn within 30 minutes after the intravenous injection. No free

> resveratrol was present in blood samples drawn after oral doses.

>

> It is therefore highly unlikely that resveratrol supplements can have

> any effect on cardiovascular disease or cancer of such organs as the

> breast or prostate gland without entering the bloodstream, said Dr

> Walle, presenting the results at this week's Experimental Biology

> meeting in Washington.

>

> However, he adds, it is still possible that orally administered

> resveratrol can prevent cancers along the aerodigestive tract. It is

> also possible that a resveratrol sulphate conjugate detected in the

> circulating blood may exert the preventive activities claimed for

> resveratrol but these questions remain to be answered.

>

> Sinclair, assistant professor at the Department of Pathology at

> Harvard Medical School, claims that such supplements are biologically

> inactive since " they don't duplicate the airless environment like a

> bottle of wine " .

>

> A new supplement that claims to do this, called Longevinex, uses

> Capsugel's airtight capsule Licap to preserve resveratrol the way it

> is found in a corked bottle of wine and is said to be the first to

> provide stabilised resveratrol, according to the US scientist.=20

>

> http://tinyurl.com/m49eu

>

>

>

>

>

Jewell, Ph.D.

Campus Mass Spectrometry Facilities

UC

cmsf.ucdavis.edu

[Guest guest]

Hi All and Willianm,

That the product works when injected into the blood

indicates quite well, I would say, that when injested

something happens to the compound such that it is not

active in the blood steam, where it should be. It

works when injected and who injects it?

--- Jewell <wtjewell@...> wrote:

> Most beneficial drugs you take are metabolized by

> your body to other forms

> such as glucuronides. Some of these circulating

> forms are actually *more*

> bioactive than the parent form. So its possible

> the resveratrol

> metabolites are possibly less or possibly more

> bioactive/potent.

>

> Unfortunately, synthesizing these metabolites in

> any meaningful amounts to

> do the appropriate studies to see how good they

> might be is pretty outrageous.

>

> The main fact remains that red wine shows positive

> health effects.

> Something in it (or its metabolites) is " good " for

> us.

-- Al Pater, PhD; email: old542000@...

__________________________________________________

[Guest guest]

This is an older study that presumed that only free resveratrol could be

of any utility. Later studies have suggested that the sulphate and

glucuronic acid conjugates might in fact enable a greater bioavailability

of resveratrol in the system and in fact protect the resveratrol from

degradation or excretion, thereby _enhancing_ its biological usefulness

in the body after its having passed into the bloodstream from the

digestive tract.

Maco

Scientists question power of

resveratrol supplements

4/22/2004 - Supplements of resveratrol, the compound found in red

wine

that is thought to fight heart disease, is unlikely to have any

effect

on preventing most cancers, said researchers this week.

The antioxidant compound found in grapes, peanuts and several

berries

has been proposed as an explanation for the low incidence of

cardiovascular disease in wine-drinking southern European

countries.

It has also been shown to possess anti-inflammatory and anti-cancer

activity in cell-based experiments and is currently in clinical

trials

for its ability to treat oral herpes and cancer.

But new research shows, that taken in supplements, the ingredient

does

not reach the circulating blood in sufficient amounts to have

therapeutic effects.

Dr Walle and colleagues from the Medical University of South

Carolina gave resveratrol to six healthy adults aged between 23 and

29. The chemical was tagged with a radioactive marker known as

Carbon-14, which allows researchers to later detect it in tissues

and

blood. It was also given intravenously to the volunteers.

They found that the 25 mg doses of resveratrol were very well

absorbed

after oral dosing with most of the dose appearing in the urine in

the

first 12 hours. However, the urine contained resveratrol only as

sulphate and glucuronic acid conjugates, none as the free,

presumably

active, form.

Likewise, the only blood samples containing free resveratrol were

those drawn within 30 minutes after the intravenous injection. No

free

resveratrol was present in blood samples drawn after oral doses.

It is therefore highly unlikely that resveratrol supplements can

have

any effect on cardiovascular disease or cancer of such organs as the

breast or prostate gland without entering the bloodstream, said Dr

Walle, presenting the results at this week's Experimental Biology

meeting in Washington.

However, he adds, it is still possible that orally administered

resveratrol can prevent cancers along the aerodigestive tract. It is

also possible that a resveratrol sulphate conjugate detected in the

circulating blood may exert the preventive activities claimed for

resveratrol but these questions remain to be answered.

Sinclair, assistant professor at the Department of Pathology

at

Harvard Medical School, claims that such supplements are

biologically

inactive since " they don't duplicate the airless environment like

a

bottle of wine " .

A new supplement that claims to do this, called Longevinex, uses

Capsugel's airtight capsule Licap to preserve resveratrol the way it

is found in a corked bottle of wine and is said to be the first to

provide stabilised resveratrol, according to the US scientist.

http://tinyurl.com/m49eu