Probiotic Bifidobacterium lactis, anti-oxidant vitamin E/C and anti-inflammatory dha attenuate lung inflammation due to pm2.5 exposure in mice

Abstract

The incidence of asthma and allergic diseases of the airways is constantly increasing, both in the industrialised and developing countries, due to harmful and excessive quantities of air pollution. Although some studies have shown an effect of dietary supplementation of specific nutrients (especially with anti-oxidant and anti-inflammatory properties) in reducing airways inflammatory response, the results are not yet conclusive and the science is still at its infancy. Our hypothesis is that combining such nutrients could provide more benefits than using them alone. The aim of the research project proposed here is to investigate whether specific combinations of nutrients (docosahexanoic acid, vitamin C and E, and Bifidobacterium lactis strain BB-12®, included in an engineered diet) can act synergistically to reduce inflammation given by high level of air pollution. Beside the role of docosahexanoic acid, vitamins C and E on airways inflammatory disease, no study examined the effect of the supplementation of this probiotic strain in pathological conditions caused by air pollution so far. Herein we used a well-established in vivo model for the study of pollution effects, which consists in female BALB/c mice receiving by pharyngeal aspiration either a sham or a particulate matter with diameter <2.5 μm (PM 2.5) containing aerosol. Before treatment, mice were fed either a chow or a supplemented diet. By performing histological analyses and gene expression profiles on lung sections and serum measurement of the cytokine interleukin 10, we found that a specific combination of all the aforementioned nutrients rather than nutrients alone had a synergistic protective effect against PM2.5-induced inflammation. In conclusion, our study support that a supplemental nutritional intervention based on a combination of the probiotic B. lactis BB-12, the anti-oxidant vitamin C and E, and the anti-inflammatory docosahexanoic acid represents a rational option for alleviating air pollution-related lung inflammation.