Epigallocatechin Gallate Attenuates Hip Fracture-Induced Acute Lung Injury by Limiting Mitochondrial DNA (mtDNA) Release

Abstract

BackgroundThe aim of this study was to assess the protective effects and explore the mechanism of epigallocatechin gallate (EGCG) in hip fracture-induced acute lung injury.Material/MethodsThirty male Sprague-Dawley (SD) rats were randomly divided into the control group, hip fracture group, and hip fracture + EGCG (10 mg/Kg) group. After 24 h, blood samples, bronchoalveolar lavage fluid (BALF), and lung tissue were collected. Serum mitochondrial DNA (mtDNA) was measured by RT-PCR and BALF was used to perform cytological analysis and enzyme-linked immunosorbent assay (ELISA) assay. Lung tissue was used to evaluate the injury level.ResultsEGCG significantly reduced the hip fracture-induced high level of serum mtDNA (p<0.05). HE staining showed protective effects of EGCG. Lower lung injury score and wet/dry ratio were identified in the hip fracture + EGCG group than in the hip fracture group (p<0.05). We found significantly lower levels of infiltration of inflammatory cells and production of inflammatory cytokines in the BALF of the hip fracture + EGCG group than in the hip fracture group (p<0.05).ConclusionsOur study found that EGCG had protective effects on hip fracture-induced acute lung injury and suggests that EGCG exerts its protective effects through limiting the release of mtDNA. Our results provide a novel pharmacological agent to attenuate hip fracture-induced acute lung injury, as well as a potential theory to better explain the anti-inflammatory property of EGCG.