Nitraria tangutorum Bobr.-derived polysaccharides protect against LPS-induced lung injury.

Nitraria tangutorum Bobr. is suggested to be active in immunoregulation and antioxidation. However, the in vivo bioactivity of N. tangutorum Bobr.-derived polysaccharides (NTP) and their anti-inflammatory activity have not been addressed. In the present study, we extracted and purified polysaccharides from N. tangutorum Bobr. and determined their anti-inflammatory activities in vivo. HPGPC, UHPLC/DAD, and NMR analyses identified that the monosaccharide components of NTP were Man, Rha, GalUA, Glu, Gal, and Ara, with relative contents of 3.52%, 15.08%, 10.00%, 26.73%, 38.08%, and 6.59%, respectively. In mice with lipopolysaccharide (LPS)-induced Acute Lung Injury (ALI), NTP treatment attenuated tissue damage, inhibited the production of inflammatory cytokines, and promoted the anti-oxidative response. The supposed mechanism may be via suppressing the Toll-like receptor 4 (TLR4) signaling pathway. In conclusion, our study suggests a protective role of NTP in LPS-induced ALI by inhibiting inflammatory damage.