Regulation of rhubarb on heat shock protein 70 expression and lung protection in rats with hyperoxia-induced new bronchopulmonary dysplasia

Abstract

Objective To investigate the effect of rhubarb on hyperoxia-induced new bronchopulmonary dysplasia (BPD) in rats. Methods Full-term Sprague-Dawley rats were exposed or not (control group) in 600 ml/L oxygen 4 days after birth and injected with normal saline (BPD group), rhubarb (BPD+ rhubarb group) or a combination of rhubarb with quercetin (BPD+ rhubarb+ quercetin group). Immunohistochemical staining was used to detect the pathological changes of the rat lungs.HSP70 expression level was quantified by western blot. Results Compared with control group, BPD group showed decreased radial alveolar 14 and 21 days after the drug treatment, which was rescued by the coexistence of rhubarb.Quercetin, as an inhibitor of HSP70, counteracted the effect of rhubarb.The lung of the BPD+ rhubarb+ quercetin group showed a similar phenotypic change with that of the BPD group.In addition, the expressions of HSP70 in lung tissues of rhubarb group at 14 days and 21 days after the treatment were higher than those of other groups, there were significant differences between rhubarb group and other groups(F=62.46, P<0.01; F=95.90, P<0.01). Conclusion Rhubarb may attenuate the hyperoxia-induced new bronchopulmonary dysplasia in rats by activating HSP70 expression. Key words: Heat shock protein 70; Bronchopulmonary dysplasia; Rhubarb; Hyperoxia