Anti-inflammatory lipid
Researchers at the US National Institute of Allergy and Infectious Diseases have identified a natural lipid – a wax–like fatty acid - used by tularemia-causing bacteria to suppress the immune response of an infected organism and increase the likelihood of developing the disease. This finding may form the basis of a new powerful anti-inflammatory therapy designed to treat diseases of bacterial and viral nature.
Tularemia is a life–threatening disease caused by the bacteria Francisella tularensis and transmitted to humans through the bites of infected animals, mosquitoes, ticks or deer flies. The disease is cured with the help of antibiotics, but is very poorly diagnosed, mainly due to the ability of the pathogen to suppress the immune response of the body.
It is known that lipids are necessary for F.tularensis bacteria to suppress inflammation that develops when cells are infected. The authors found that a special form of phosphatidylethanoloamine lipid is responsible for this, the composition of which differs from the composition of lipids of other bacteria.
After identifying phosphatidylethanoloamine as an immune-suppressing factor, the researchers decided to evaluate its potential therapeutic significance. Since live F.tularensis are very contagious and working with them is dangerous to health, they developed and synthesized artificial analogues of the compound – lipids PE2410 and PEPC2410. Their ability to suppress the immune response during infection of the body has been demonstrated in experiments on human and mouse cells.
An image obtained using a fluorescent microscope showing the accumulation of phosphatidylethanoloamine (red) in human dendritic cells after introduction into culture of liposomes containing a synthetic analog of phosphatidylethanoloamine Francisella tularensis. The cell nuclei are colored blue.
Considering that some types of viral infections are accompanied by the development of a strong inflammatory reaction, the authors tested natural and synthetic forms of lipid on human cells infected with the dengue virus. All variants of the compound suppressed the immune response compared to the immune response developing in the culture of infected cells without the addition of phosphatidylethanoloamine. (The dengue virus is spread by Aedes aegypti mosquitoes and is rarely fatal. However, the disease is accompanied by severe fever, severe headaches and generalized pain syndrome. There is no specific therapy for dengue fever.)
Scientists plan to continue studying the mechanisms that allow F.tularensis to suppress the immune response of the infected organism. They hope that the data they have obtained will allow the development of a powerful broad-spectrum anti-inflammatory drug in the future.
Article by Ireland et al. Unique Francisella phosphatidylethanolamine acts as a potent anti-inflammatory lipid published in the Journal of Innate Immunity.
Evgenia Ryabtseva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the National Institutes of Health: Natural Lipid Acts as a Potential Anti-Inflammatory.