Preventive effect of quercetin in smoke inhalation injury in rats

Objective: To explore the protective effects of quercetin on smoke inhalation injury in rats.Methods: Forty male SD rats were randomly divided into four groups.Group A: control group(n=10),Group B: injured group(n=10),Group C: quercetin treated group(n=10) and Group D:quercetin prevented group(n=10).Three hours after smoke inhaled injured,the rats in group C were all injected intraperitoneally with quercetin(200 mg/kg).Ten minutes before smoke inhaled injured,the rats in group D were all injected intraperitoneally with quercetin(200 mg/kg),at the same time the group B were injected the same volume normal saline.The rats were treated by no measures in control group.At the time of 72 hours after smoke inhaled injured,the blood samples 5 mL were collected from abdominal aorta and the lung tissue.The levels of tumor necrosis factor-α(TNF-α),interleukin-6(IL-6) in serum as well as the levels of malondialdehyde(MDA),inducible nitric oxide synthase(iNOS) and superoxide dismutase(SOD) in lung tissue were tested.Lung tissues were checked for moisture and examined under microscope.Results: The levels of TNF-α,IL-6,iNOS and MDA in group C were lower than those in group B(P 0.01),and the SOD were higher(P 0.01).The above changes were more evident in group D(P0.01).Pathology showed thickened alveolar space,inflammatory cells effusion,and local hemorrhage in group B,inflammatory granulocytes were improved in group C and group D.Compared with group C,pulmonary edema was found to be lower in the group D.Conclusion: Quercetin has protective effects on smoke inhalation injury by relieve pulmonary edema,scavenging free radical and inhibiting proinflammatory cytokines.The effects of quercetin on smoke inhalation injury is better in prevention.