Dietary New Zealand propolis supplementation reduced proinflammatory cytokines in an acute mouse model of air pollution exposure, without impacting on immune cell infiltration or lung function

Air pollution is estimated to cause 7 million annual deaths globally. Our aim was to determine if dietary propolis consumption could prevent the immune and functional damage in a mouse model of acute urban dust exposure. Female C57BL/6J mice were challenged three times with intranasal urban dust over seven days which significantly increased proinflammatory cytokines and immune cells in the lung 24 h post final challenge. Dietary New Zealand propolis (2%) with gamma cyclodextrin supplementation reduced urban dust-induced lung TNF alpha, IL-4, and IL-6 cytokine production; but did not alter immune cell infiltration into the lung, or lung function outcomes. This suggests that daily consumption of 8% propolis with gamma cyclodextrin supplemented food was sufficient to reduce urban dust pollution-induced proinflammatory cytokine production but was not sufficient to prevent immune cell recruitment into the lung or lung function decline in a murine model of lung inflammation.