Shen-su-yin, a Traditional Herbal Medicine, Attenuates Lipopolysaccharide-induced Acute Lung Injury in Rats Through Its Anti-inflammatory and Anti-oxidative Effects

Abstract

Most components of Shen-su-yin (SSY), an herbal formula, have anti-inflammatory and antioxidant activities. The present study was designed to investigate potential effects and mechanisms of SSY on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats. 48 rats were randomly divided into 4 groups: control (Ctrl) group, LPS-induced ALI group, low- (SSY-LD) and high- (SSY-HD) dose SSY-treated ALI group. SSY was administered to SSY-treated rats immediately after LPS induction. After 24 hours, blood gas analysis and lactate determination were performed; and bronchoalveolar lavage fluid was collected for detecting protein concentration and levels of cytokines. Lung tissues were obtained for Western blot analysis, histopathological analysis, wet-to-dry weight ratio calculation and measurement of oxidative stress levels. SSY improved oxygenation index and mean arterial pressure, decreased levels of lactate and heart rate, alleviated lung histopathology indexes including lung injury score, wet-to-dry weight ratio and exudation of protein as well as inflammatory cells in ALI rats. Furthermore, SSY reduced levels of pro-inflammatory and oxidative mediums, while increasing levels of anti-inflammatory cytokine and anti-oxidative activity in lung tissues. SSY also suppressed NF-κB signalling pathway and further activated Keap1-Nrf2-ARE signalling pathway activated by LPS. Moreover, all the effects caused by SSY in the SSY-HD group were more encouraging than those in the SSY-LD group. The results indicate that the preventive use of SSY can alleviate ALI through the anti-inflammatory and antioxidant effects mediated by inhibition of NF-κB signalling pathway and activation of Keap1-Nrf2-ARE signalling pathway, and the effect of high dose is better.