DHA omega-3 fatty acids reduce stroke damage
Stroke: less risk with omega-3 fatty acids
Confirmed benefits of the omega-3 fatty acid DHA (docosahexaenoic acid) against stroke. According to a study from Université Laval in Ville de Quebéc (Canada), this fatty acid can reduce damage from this brain event by 25 percent.
The news comes from the pages of the journal Stroke, where the authors point out that consumption of omega-3 DHA creates anti-inflammatory and neuroprotective conditions in the brain that counteract the damage caused by stroke. In this way, explains Jasna Kriz, study coordinator, omega-3 prevents the acute inflammatory response that would follow the event, which is very dangerous for nerve tissue.
The modulation of the immune response
The research authors came to these conclusions using mice genetically predisposed to develop a stroke as a model organism. The critters were divided into three groups, each of which was fed different amounts of DHA. While the control mice received a diet devoid of DHA, a second group received low doses of theomega-3 fatty acid. The remaining guinea pigs consumed about 0.7 grams of DHA per kg of body weight each day, corresponding to a massive dose of Omega-3. After three months, a reduction in the levels of inflammation-stimulating compounds was observed in the mice belonging to the third group.
These include COX2, one of the proteins responsible for the production of prostaglandins--factors involved in inflammatory processes--and interleukin-1beta (IL-1beta), a molecule that promotes inflammation--for example, during bacterial infections--promotes prostaglandin synthesis and stimulates immune system activation.In addition to reducing levels of inflammation-inducing molecules,DHA intake led to increased production of factors that counteract the activation of cell death phenomena. Not only that, the administration of high doses of DHA also caused an increase in the ratio of Omega-3 fatty acids to Omega-6 fatty acids. Specifically, Omega-3 fatty acid would at least partially replace another molecule, arachidonic acid, an omega-6 fatty acid known for its ability to induce inflammation.
Omega-3 benefits for the brain
According to the researchers, this is the first convincing demonstration of the powerful anti-inflammatory action exerted by DHA in the brain. And, reported to humans, it would indicate 42 grams of DHA as the amount of Omega-3 that a 60 kg man would need to take daily to achieve the same effects that the Canadian researchers showed in mice. However, Frédéric Calon, a co-author of the study, explained that mice have a faster metabolism than humans and, taking into account the 2,000 calories consumed, on average, by an adult, these 42 grams could be reduced to 2.5-3 grams of DHA or EPA (eicosapentaenoic acid, another important Omega-3) per day.
Source:
1. Lalancette-Hébert M, Julien C, Cordeau P, Bohacek I, Weng YC, Calon F, Kriz J, "Accumulation of Dietary Docosahexaenoic Acid in the Brain Attenuates Acute Immune Response and Development of Postischemic Neuronal Damage." Stroke. 2011 Aug 18. [Epub ahead of print].
