Flaxseed could reduce oxidative damage / inflammation

[Guest guest]

Hi all,

Mouse study shows supplemental flaxseed could reduce oxidative tissue damage and inflammation in the lung.

link and full text of article copied below.

Dave

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http://www.nutraingredients.com/news/ng.asp?n=67942 & m=1NIE524 & c=lqeudkujayvvlpc

Flaxseed could boost lung health, animal study

24/05/2006-

A dietary

supplement of flaxseed, a rich source of lignans and omega-3 fatty

acids, could prove useful to receive lung inflammation and oxidative

stress, if results from a mice study can be expanded to humans.

Flaxseed contains high concentrations of both omega-3 fatty acids and

lignans, particularly secoisolariciresinol diglucoside (SDG), which is

converted into enterodiol and enterolactone in the colon. There is some

evidence that enterolactone, a phytoestrogen, may have a beneficial

effect on bone health, breast health, heart health, hair loss, acne,

inflammation, with the main focus being for prostate and menopause

health, and as an antioxidant.

If the preliminary results from the mice studies can be applied to

humans, this could be open up a new outlet for flaxseed. The North

American market for flax lignan-containing specialty supplements saw

growth of 8.1 per cent overall in 2004 over over the previous year, and

annual sales were over $2.9bn.

"To our knowledge, our study shows here the first supporting

evidence to indicate that dietary supplementation with flaxseed can

ameliorate oxidative tissue damage and inflammation in certain forms of

experimental acute lung injury," wrote lead author Kinniry in the Journal of Nutrition (Vol 136, pp 1545-1551).

The researchers, from the University of Pennsylvania and North Dakota

State University, supplemented the diet of female mice with five and

ten per cent flaxseed (Purina Mills) for up to ten weeks. The mice were

divided into two groups; one group received the supplemented diet (test

group) while the other received only the standard AIN-93G diet (control

group).

Vitamin E was removed from the diet mix and, because flaxseed contains

a small amount of the vitamin, each diet was standardised to contain a

constant 3.35 mg per kg, attained by adding appropriate amounts of

dl-alpha-tocopheryl acetate.

The mice were further divided into four different groups; three groups

had induced lung damage by acid aspiration, administration of

lipopolysaccharide solution (LPS), or hyperoxic (excess oxygen in the

tissues) conditions. The fourth group was untouched and used as

control. The degree of lung damage was evaluated by measuring

malondialdehyde (MDA) concentrations, a reactive carbonyl compound.

The researchers, led by Professor Melpo Christofidou-Solomidou, found

that both doses of flaxseed supplementation resulted in decreased

levels of MDA after acid aspiration and hyperoxia, but not LPS

conditions.

Supplementation with ten per cent flaxseed, for example, reduced MDA

levels by a significant three micromoles per gram of lung tissue,

compared to unsupplemented mice exposed to acid aspiration.

MDA levels also decreased in lung tissue of mice eating the ten per

cent flaxseed diet after hyperoxia, falling from 7.5 micromoles per

gram of lung tissue in the untouched mice, to 5 micromoles per gram of

lung tissue in the hyperoxia mice.

"Acid aspiration results in a dramatic increase in lung permeability," explained the authors. "Aspiration

of gastric contents [which are acidic] is one of the most common causes

of acute injury or acute respiratory distress syndrome (ARDS), and is

reported to be associated with a 25 to 35 per cent incidence of ARDS."

Over 150000 Americans are diagnosed with ARDS every year, which is

equivalent to 17 people per hour, according to the ARDS Foundation. The

syndrome is defined as an acute process that leads to moderate to

severe loss of lung function.

Since flaxseed contains both omega-3 fatty acids and flax lignans the

authors were unable to determine which were the bioactive components.

But the researchers did suggest that the possible protective mechanism

could be due to the antioxidant activity of the flax lignans.

"The flaxseed lignan SDG and its metabolites (enterodiol and

enterolactone) have known antioxidant activities, shown both in vitro

and in vivo systems, that are exerted mainly through the inhibition of

lipid peroxidation," said Kinniry.

Lipid peroxides can then undergo further decomposition to produce

compounds like MDA, said the researchers, adding to the oxidative

stress on the tissues. This by inhibiting the lipid peroxidation

process, oxidative stress on the lungs may be reduced.

Further study should focus on determining tissue lignan levels. Prof

Christofidou-Solomidou told NutraIngredients.com that work was

continuing in this field with "even more exciting data with dietary flaxseed in additional, clinically relevant disease models (in mice)," already generated.

"We are very excited to pioneer the work of flaxseed in the context of acute lung disease," she said.