<i>Lily bulb</i> Nectar Produces Expectorant and Anti-Tussive Activities, and Suppresses Cigarette Smoke-Induced Inflammatory Response in the Respiratory Tract in Mice

Air pollutants pose a major environmental threat to the respiratory system. Pathogen invasion and the exposure to particulate matters in atmospheric air, particularly, cigarette smoke (CS), have been found to be associated with acute and chronic respiratory diseases, including asthma. Therefore, the search for agents that can protect the respiratory system against potentially harmful substances is of interest in preventive health. Lily bulb Nectar (LBN), which contains Lily bulb, Pyrus pyrifolia N., Siraitia grosvenorii and Apricot kernel as its ingredients, is a health supplement intended to improve the wellness of the respiratory system in humans. Lily bulb, Pyrus pyrifolia N., Siraitia grosvenorii and Apricot kernel are commonly prescribed for the treatment of respiratory tract disorders such as bronchitis, pneumonia and cough in the practice of traditional Chinese medicine. Pharmacological studies have shown that these herbs can produce beneficial effects on the respiratory tract or even the lungs. In the present study, we investigated the effects of LBN on mouse respiratory tract function under normal and challenged conditions. LBN was first examined for its expectorant and anti-tussive activities in mice. The effect of LBN on long-term exposure to CS was also investigated. Our findings showed that long-term LBN treatment enhanced the expectorant activity and suppressed the SO2-induced coughing in mice. LBN treatment also suppressed the CS-induced inflammation in the respiratory tract, as assessed by differential cell count and cytokine production. In conclusion, long-term LBN consumption may produce beneficial effects on the respiratory tract function in humans, particularly in the face of challenge by irritants in the inhaling air