Oligosaccharides from Asparagus cochinchinensis for ameliorating LPS-induced acute lung injury in mice

Asparagi radix is an edible herb with medicinal properties and is now widely used in clinical applications for improving pulmonary inflammation. However, the lung-protective effect and the active constituents of Asparagi radix are yet to be elucidated. Herein, the potential pulmonary protective effect of the oligosaccharides of Asparagi radix was investigated. We firstly identified eighteen oligosaccharides with different degrees of polymerization from Asparagi radix using HPLC-QTOF MS. Oligosaccharides were analysed for 20 samples of Asparagi radix collected from various regions in China using HILIC-ELSD and were found to stably exist in this herb. In this study, we found that AROS significantly reduced NO production and effectively down-regulated the mRNA expression of IL-6, IL-1 beta and TNF-alpha in RAW 264.7 cells, thereby reducing the inflammatory response induced by LPS. AROS also inhibited LPS-stimulated intracellular ROS production. A murine model of lipopolysaccharide (LPS)-induced acute lung injury was used to evaluate the in vivo anti-inflammatory and lung protective efficacies of AROS. AROS ameliorated the damage to the pulmonary cellular architecture pathological injury and lung edema. AROS significantly decreased the levels of cytokines IL-6, TNF-alpha and IL-1 beta; the levels of MPO and MDA; and superoxide dismutase consumption in vivo. This effect of oligosaccharides can explain the traditional usage of Asparagus cochinchinensis as a tonic medicine for respiratory problems, and oligosaccharides from Asparagi radix used as a natural ingredient can play an important role in protecting lung injury.