The protective effects of sodium butyrate on acute lung injury induced by lipopolysaccharide in rats

Abstract

Objective To investigate the protective effects of sodium butyrate on acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats.Methods Totally forty male SD rats were randomly divided into control group,SB group,LPS group and SB+LPS group.In control and SB group,the rats were given normal saline (2 ml/kg) intravenously and SB (500 mg/kg)intraperitoneally.The LPS group were injected LPS (6 mg/kg) intravenously,while the SB+LPS group received intraperitoneally injection of SB (500 mg/kg) at 0 h and 4 h after LPS administration.The animals in each group were sacrificed after the models were completed successfully for six hours.Pulmonary histological changes were evaluated by hematoxylin-eosin stain and lung wet/dry weight ratios were observed.Concentrations of tumor necrosis factor (TNF-α) and interleukin (IL)-1β and IL-8 and IL-10 and high mobility group box 1 (HMGB-1)in plasma and concentrations of nitric oxide (NO) and myeloperoxidase (MPO) activity and malonaldehyde (MDA) in lung tissue homogenates were measured by enzyme-linked immunosorbent assay (ELISA).Results LPS induced marked lung histological injury and a significant increase in W/D ratio and MPO activity as well as MDA and NO levels in lung tissue homogenates (4.48 ±0.23) vs (4.20 ±0.11),(0.84 ±0.05)vs (0.68 ±0.03),(5.75 ±0.19) vs (2.74 ±0.20),(41 ±4)vs (33 ±7) (P＜0.01).Compared with LPS group,TNF-α,IL-1β,IL-8 and HMGB-1 showed a decreasing trend in LPS+SB group(2350.23±120.76)vs (1150.45 ±153.78),(395.13 ±20.39)vs (202.69 ±18.21),(89.34 ±7.32)vs (49.65 ±5.09),(115.28 ±12.37)vs (62.18 ±15.89) (P＜0.05),while IL-10 showed a rising trend (281.23±24.56)vs(100.78±14.47)(P＜0.05).However all of these changes were significantly attenuated by posttreatment with SB (P＜0.05).Conclusions Sodium butyrate exert protective effects by inhibiting neutrophil aggregation and cytokine production as well as lung lipid peroxidation and nitro effect.Sodium butyrate can also attenuated pulmonary edema and cell damage. Key words: Lipopolysaccharide; Acute lung injury; Sodium butyrate