CLA fights inflammatory disease

October 19, 2005

CLA (conjugated linoleic acid), found naturally in dairy products and

meat, and also available as a supplement (Tonalin CLA), may be a COX-2

inhibitor.

Dave

++++++++++++++++++++++++++++

Link and full text:

http://www.nutraingredients.com/news/printNewsBis.asp?id=63313

How CLA fights inflammatory disease

19/10/2005- US scientists have explained how one of the forms of

conjugated linoleic acid (CLA), a fatty acid found in dairy products,

could reduce inflammatory disease.

The team from the University of Wisconsin-Madison say that one of the

CLA isomers is a natural regulator of the COX-2 protein, which plays a

significant role in diseases like arthritis and cancer.

" It's clear from previous research that conjugated linoleic acid, or

CLA, prevents inflammatory damage resulting from immune response, "

said Mark Cook, a professor of animal science.

" We've identified the biochemical mechanism by which this occurs. "

The new work will be welcomed by firms marketing the fatty acid for

health foods and supplements. While a number of studies have pointed

to CLA's benefits in the area of cancer prevention, experts have

warned that there is not enough evidence yet to support increasing

intake of the fat.

CLA exists naturally in a number of structural forms. Cook's team

tested both the 10trans,12cis-CLA and 9cis,11trans-CLA on COX-2

protein expression and prostaglandin production. They found the first

of these to have a significant inhibitory effect on COX-2 expression

in both the lab and an animal test.

The researchers report in this month's issue of the Journal of Lipid

Research (vol 46, issue 10, pp2134-42) that COX-2 protein expression

was inhibited 80 per cent by 10t, 12c-CLA and only 26 per cent by

9c,11t-CLA in an in vitro test.

The 10t,12c-CLA also decreased prostaglandin production more than the

other CLA form.

The mice tests confirmed the results. Animals fed this form of CLA but

not 9c,11t-CLA were found to have a 34 per cent decrease in COX-2

protein and a 43 per cent reduction of PGE(2) release in the lung.

The COX-2 protein is known to play a significant role in many

inflammatory diseases and is an important drug target for treating

arthritis and cancer.

After further analysis, the researchers found that the reduced COX-2

protein and prostaglandin release was probably caused by 10t,12c-CLA

blocking a key cellular pathway, the nuclear factor kappaB (NF-kappaB).

While the amount of the anti-inflammatory isomer of CLA in milk is

small relative to other fatty acids in milk, there may still be enough

to elicit an effect if someone consumes dairy products every day, said

Cook.

He believest that CLA could be used as a natural way to prevent

'collateral damage' from the immune system's response to invading

pathogens.

" The ideal solution is to let the immune system fight bacteria, but at

the same time to maintain the overall health of the system, " he said.

The researcher is planning a study to determine whether the amount of

anti-inflammatory CLA in milk can be increased by changing dairy cow

diets.

The current study was partially funded by BASF and Natural Lipids.

October 19, 2005

Hi Dave:

Just so that you know there is another side to this argument,

regarding conjugated linoleic acid, the conclusion of the following

study was:

" CONCLUSIONS/INTERPRETATION: In obese men, t10c12CLA induces

hyperproinsulinaemia that is related to impaired insulin sensitivity,

independently of changes in insulin concentrations. These results are

of clinical interest, as hyperproinsulinaemia predicts diabetes and

cardiovascular disease. The use of weight-loss supplements containing

this fatty acid is worrying. "

Here is the abstract:

" Supplementation with trans10cis12-conjugated linoleic acid induces

hyperproinsulinaemia in obese men: close association with impaired

insulin sensitivity.

Riserus U, Vessby B, Arner P, Zethelius B.

Department of Public Health and Caring Sciences/Geriatrics, Uppsala

University, Uppsala, Sweden. ulf.riserus@...

AIMS/HYPOTHESIS: Hyperproinsulinaemia reflects both beta cell

dysfunction and insulin resistance in cross-sectional studies, but it

is not known whether changes in proinsulin concentrations are related

to insulin resistance over time. As trans10cis12 (t10c12)-conjugated

linoleic acid (CLA) supplementation induces insulin resistance in

obese men, we used this fatty acid to investigate the effects on

plasma proinsulin, insulin, C-peptide and adiponectin concentrations,

including their associations with change in insulin sensitivity.

METHODS: We randomised (double-blind) 57 non-diabetic abdominally

obese men to receive either 3.4 g t10c12CLA, CLA-isomer mixture or

control oil for 12 weeks. Insulin sensitivity (hyperinsulinaemic-

euglycaemic clamp), intact proinsulin, insulin, the proinsulin :

insulin ratio, C-peptide, glucose and adiponectin were assessed

before and after supplementation. RESULTS: Supplementation with

t10c12CLA increased proinsulin (p<0.01), the proinsulin : insulin

ratio (p<0.05) and C-peptide concentrations (p<0.001) in comparison

with control subjects. Adiponectin, however, did not change

significantly. The change in proinsulin, but not the proinsulin :

insulin ratio, was related to impaired insulin sensitivity (r= -0.58,

p<0.0001), independently of changes in insulin, C-peptide, glucose,

adiponectin and BMI. Conversely, the correlation between insulin

sensitivity and specific insulin (r=-0.46, p<0.001) did not remain

significant after adjustment for proinsulin. Induced

hyperproinsulinaemia was also correlated to adiponectin

concentrations ( r= -0.34, p<0.01). CONCLUSIONS/INTERPRETATION: In

obese men, t10c12CLA induces hyperproinsulinaemia that is related to

impaired insulin sensitivity, independently of changes in insulin

concentrations. These results are of clinical interest, as

hyperproinsulinaemia predicts diabetes and cardiovascular disease.

The use of weight-loss supplements containing this fatty acid is

worrying.

PMID: 15168020 "

Rodney.

>

> CLA (conjugated linoleic acid), found naturally in dairy products

and

> meat, and also available as a supplement (Tonalin CLA), may be a

COX-2

> inhibitor.

>

> Dave

>

> ++++++++++++++++++++++++++++

>

> Link and full text:

>

> http://www.nutraingredients.com/news/printNewsBis.asp?id=63313

>

> How CLA fights inflammatory disease

>

> 19/10/2005- US scientists have explained how one of the forms of

> conjugated linoleic acid (CLA), a fatty acid found in dairy

products,

> could reduce inflammatory disease.

>

> The team from the University of Wisconsin-Madison say that one of

the

> CLA isomers is a natural regulator of the COX-2 protein, which

plays a

> significant role in diseases like arthritis and cancer.

>

> " It's clear from previous research that conjugated linoleic acid, or

> CLA, prevents inflammatory damage resulting from immune response, "

> said Mark Cook, a professor of animal science.

>

> " We've identified the biochemical mechanism by which this occurs. "

>

> The new work will be welcomed by firms marketing the fatty acid for

> health foods and supplements. While a number of studies have pointed

> to CLA's benefits in the area of cancer prevention, experts have

> warned that there is not enough evidence yet to support increasing

> intake of the fat.

>

> CLA exists naturally in a number of structural forms. Cook's team

> tested both the 10trans,12cis-CLA and 9cis,11trans-CLA on COX-2

> protein expression and prostaglandin production. They found the

first

> of these to have a significant inhibitory effect on COX-2 expression

> in both the lab and an animal test.

>

> The researchers report in this month's issue of the Journal of Lipid

> Research (vol 46, issue 10, pp2134-42) that COX-2 protein expression

> was inhibited 80 per cent by 10t, 12c-CLA and only 26 per cent by

> 9c,11t-CLA in an in vitro test.

>

> The 10t,12c-CLA also decreased prostaglandin production more than

the

> other CLA form.

>

> The mice tests confirmed the results. Animals fed this form of CLA

but

> not 9c,11t-CLA were found to have a 34 per cent decrease in COX-2

> protein and a 43 per cent reduction of PGE(2) release in the lung.

>

> The COX-2 protein is known to play a significant role in many

> inflammatory diseases and is an important drug target for treating

> arthritis and cancer.

>

> After further analysis, the researchers found that the reduced COX-2

> protein and prostaglandin release was probably caused by 10t,12c-CLA

> blocking a key cellular pathway, the nuclear factor kappaB (NF-

kappaB).

>

> While the amount of the anti-inflammatory isomer of CLA in milk is

> small relative to other fatty acids in milk, there may still be

enough

> to elicit an effect if someone consumes dairy products every day,

said

> Cook.

>

> He believest that CLA could be used as a natural way to prevent

> 'collateral damage' from the immune system's response to invading

> pathogens.

>

> " The ideal solution is to let the immune system fight bacteria, but

at

> the same time to maintain the overall health of the system, " he

said.

>

> The researcher is planning a study to determine whether the amount

of

> anti-inflammatory CLA in milk can be increased by changing dairy cow

> diets.

>

> The current study was partially funded by BASF and Natural Lipids.

>

October 19, 2005