Polydatin attenuates ipopolysaccharide-induced acute lung injury in rats

Anti-inflammatory and anti-apoptotic effects of polydatin (PD) have been demonstrated in our previous studies. Recently, we have found that PD treatment can ameliorate burn-induced acute lung injury (ALI). In the present study, we hypothesized that PD may provide protective effect against LPS-induced ALI through reducing inflammation and apoptosis. Rats were respectively pretreated with PD at doses of 15, 30 and 45 mg/kg weight, followed by intratracheal administration of lipopolysaccharide (LPS). LPS-challenged rats exhibited significant lung injury characterized by the deterioration of histopathology, pulmonary microvascular hyperpermeability, wet-to-dry weight ratio, and oxygenation index, which was attenuated by PD (30 and 45 mg/kg) treatment. Moreover, PD (30 and 45 mg/kg) treatment inhibited LPS-induced inflammatory response, as evidenced by the downregulation of lung myeloperoxidase activity, total cells and PMNs in bronchoalveolar lavage fluid, and the systemic levels of the pro-inflammatory cytokines. Furthermore, PD (30 and 45 mg/kg) treatment remarkably improved LPS-induced increase in TUNEL (deoxynucleotidyl transferase dUTP nick end labeling) staining-positive cells, caspase 3 activity, Bax over-expression and Bcl-2 down-expression. In conclusion, these results demonstrate that PD (30 and 45 mg/kg) treatment attenuates LPS-induced ALI through reducing lung inflammation and apoptosis.