Lycium barbarum polysaccharide attenuates Pseudomonas-aeruginosa pyocyanin-induced cellular injury in mice airway epithelial cells

BACKGROUND: Lycium barbarum berries have been utilized in Asia for many years. However, the mechanisms of its lung-defensive properties are indeterminate. OBJECTIVE: We investigate whether L. barbarum polysaccharide (LBP) could weaken Pseudomonas aeruginosa infection-induced lung injury. DESIGN: Mice primary air-liquid interface epithelial cultures were pretreated with LBP and subsequently treated with pyocyanin (PCN). Lung injury, including apoptosis, inflammation, and oxidative stress, was estimated by western blot, enzyme-linked immunosorbent assay, and real-time quantitative polymerase chain reaction, Real-time qPCR (Q-PCR). Flow cytometry was used to test cell apoptosis. Moreover, Balb/c mice were used to evaluate the tissue injury. We used hematoxylin-eosin staining and immunofluorescence to detect the expression of related proteins and tissue damage in mouse lungs and spleen. RESULTS: The flow cytometric analysis shows the potential of LBP to reduce time-dependent cell death by PCN. Mechanistically, LBP reduces PCN-induced expression of proapoptotic proteins and caspase3 and induces the activation of Bcl-2 in mice bronchial epithelial cells. Similarly, LBP reduces PCN-induced intracellular reactive oxygen species (ROS) production. Moreover, LBP inhibits the production of inflammatory cytokines, Interleukin (IL-1β), Tumor Necrosis Factor (TNF), IL-6, and IL-8. Our study confirms the ability of LBP to retard PCN-induced injury in mice lung and spleen. CONCLUSIONS: The inhibition of PCN-induced lung injury by LBP is capable of protecting mice cells from injury.