Preventive and therapeutic effects of suramin on lipopolysaccharide-induced mouse model of acute lung injury and its molecular mechanism / 中华急诊医学杂志

ABSTRACT

Objective The purpose of this research is to study the preventive and therapeutic effects of suramin on lipopolysaccharide (LPS)-induced mouse model of acute lung injury and its molecular mechanism.Methods A total of 24 healthy male C57BL/6 mice were randomly divided into two groups Control group and suramin group.LPS (5 mg/kg, iv) induced acute lung injury model was used in this study.The severity of lung injury was evaluated using haematoxylin-eosin (HE) staining after the injection of LPS for 0, 24 and 72 hours.The expression of TNF-α and IL-6 mRNA levels were also detected by RT-PCR.In vitro, THP-1 cells were stimulated by LPS (100 ng/mL) with saline or suramin pre-treatment.The expressions of p-ERK1/2, p-JNK and p-P38 were analyzed by Western blot at 10 min, 20 min and 30 min after LPS insult.A 2-tailed Student's t test was used to compare difference between two independent groups.Results Compared with the saline group, the lung tissues injury were significantly decreased in the suramin group of 72 hours after the injection of LPS (saline 3.90 ±0.35;suramin 2.50 ±0.12) (t =7.668, P ＜ 0.01).The expressions of TNF-α (saline 8.35 ± 1.63;suramin 4.62 ± 0.70) (t =4.187, P＜0.01) andIL-6 (saline10.53 ± 2.10;suramin5.53±1.10) (t=4.224, P＜0.01) mRNA were also obviously reduced in suramin group after the injection of LPS for 24 hours.The expression levels of pERK1/2, p-JNK and p-P38 were obviously down-regulated by suramin at 10 min, 20 min and 30 min after LPS stimulation.Conclusion Suramin protected LPS-induced acute lung injury through down-regulating the expression of pro-inflammatory factors, which was closely relative to the inhibition of the MAPK pathway.