Researchers at Michigan State University have received a five-year $2.3 million grant to learn how the omega-3 fatty acid DHA can stop the development of systemic lupus erythematosus after exposure to silica.
The team’s earlier research showed that eating food rich in DHA acted to prevent silica from triggering lupus, but so far, they have not understood how the nutrient does so.
“When lupus is triggered by fine inhalable particles called crystalline silica in the lungs, our earlier research has shown that DHA essentially stopped the activation of the disease,” James Pestka, a distinguished professor of food science and human nutrition, said in a press release.
People at construction, agriculture, and mining sites are typically at risk of inhaling tiny particles of silica — a toxic mineral that triggers a devastating lung inflammation. Pestka, together with colleagues Jack Harkema, who is a pulmonary pathologist, and Jenifer Fenton, a nutritional biochemist, will lead the new study.
So far, the researchers envision certain possible scenarios. The DHA found in fatty, cold-water fish might, for example, change the way lung cells react to silica and stop the immune system from also launching an aggressive attack damaging healthy cells, according to Harkema.
“Cells in the lung can gobble up the silica, but it’s so toxic, it usually kills these cells,” Harkema said. “When they die, signals are sent out to the immune system that something is wrong. The body then produces such a strong response that it also starts killing healthy cells.”
In addition to the theory that DHA might prevent the immune system from overreacting, researchers consider the possibility that DHA allows cells to clear silica from the lungs without being damaged.
Their earlier work showed that in female mice genetically prone to develop lupus, DHA prevented a vast majority of lung lesions when the animals were exposed to silica.
“Ninety-six percent of the lung lesions were stopped with DHA after being triggered by the silica,” Harkema said.
While researchers believe that genetic factors are important contributors to the development of lupus, many other environmental factors, in addition to silica, are believed to trigger the disease.
“Lupus is the body’s immune system attacking itself and it can damage any part of the body including skin, joints and organs,” Pestka said. “This new research will let us see what happens at the cellular level in the triggering of lupus and how we can intervene nutritionally with DHA to prevent the flaring and progression of the disease.”
The grant, provided by the National Institutes of Health, will also allow researchers to study how other substances that enter the lungs, such as diesel exhaust, might trigger lupus.