When given to mice, omega-3 fatty acids were found to reduce the inflammation and oxidative stress caused by air pollution.
“We discovered that fine particulate matter not only accumulates in the lungs but can also penetrate the pulmonary barrier and travel into other organs, including the brain, liver, spleen, kidney, and testis. These particles induced both pulmonary and systemic inflammation and increased oxidative stress,” the study authors said.
“We also show that elevating tissue levels of omega-3 fatty acids was effective in reducing fine particle-induced inflammation, whether as a preventive method (prior to exposure) or as an intervention (after exposure).”
Increasing tissue OFA levels may be a promising nutritional means for reducing the risk of diseases caused by particle exposure.
Previous human studies have showed that omega-3 polyunsaturated fatty acid supplementation has beneficial effects on particle-induced increases in heart rate. In addition, research using human cells appears to offer additional support.
Study procedure
In the study, lead study author Dr Jing Kang, director of the Laboratory for Lipid Medicine and Technology at Massachusetts General Hospital, used synthetic, non-toxic, fluorescent fine particles to investigate the distribution of inhaled fine particles and their effects on pulmonary and systemic inflammation in mice.
After fine particle exposure, the control and fine particle exposure (PM) groups were placed on a Western diet for two months.
One group of mice (PM2.5), which were exposed to fine particles lower than 2.5 micrometres (μm) in diameter that are considered especially harmful to health, received a modified Western Diet enriched with OFAs.
“Our study was able to address a fundamental and universal question on the impact and distribution of fine particulate matter in general, not just a specific or localised type of fine particulate matter,” the authors concluded.
“As foreign particles in the body, fine particles can trigger inflammatory responses and oxidative stress pathways in affected organs.”
The deficiency of OFA is a modern nutritional problem and has been linked to the increase in chronic disease cases. This has given rise to nutritional strategies based on OFAs that could have a great impact on public health.
According to Dr Kang, the doses administered to the mice would be equivalent to 2-4 grammes (g) per day in humans – approximately two 85 g portions a day of oily fish such as mackerel or salmon.
Back in 2012, EFSA stated that daily supplemental intakes of 5 g of OFA types, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) combined, up to 1.8 g/day of EPA alone and 1 g/day of DHA alone, were not considered a safety concern for adults.
EFSA said actual intakes of EPA and DHA from food and food supplements in Europe were generally below these amounts.
Study highlights
A strength of the study centres on its use of specific mouse models that give further weight to the anti-inflammatory effects of OFAs rather than other nutrients in the diet.
Its well-documented anti-inflammatory and antioxidant properties act through multiple pathways and have been used in the prevention and treatment of inflammation-related chronic illnesses.
“Omega-3 fatty acids could ameliorate the adverse health effects of fine air pollution by suppressing the body's inflammatory response to fine particulate matter, and thereby reduce the risk for chronic disease development,” the team theorised.
Dr Kang and his team also proposed the existence of another mechanism by which OFAs could reduce fine particle-induced inflammation.
By minimising the penetration of fine particles from the lungs into other organs, the team opened up another avenue of research. However, the present study could not address this due to technical limitations.
Source: Biochimica et Biophysica Acta (BBA)
Published online ahead of print: doi.org/10.1016/j.bbagen.2016.12.018
“Protection against fine particle-induced pulmonary and systemic inflammation by omega-3 polyunsaturated fatty acids.”
Authors: Jing Kang et al