Therapeutic effects of quercetin against smoke inhalation injury in rats

Objective To study the therapeutic effects of quercetin against smoke inhalation injury in rats. Methods Forty-two male SD rats were randomly divided into three groups: group A(n=6), group B(n=18), and group C(n=18). The latter two groups in accordance with 6 h, 24 h and 48 h after injury were each divided into three groups (B1, B2, B3, C1, C2, C3) (n=6). 3 h after smoke inhaled injured, the rats in group C were all injected intraperitoneally with quercetin(200 mg/kg), and the group B were injected the same volume normal saline. The control group received no treatment. At 6 h after injured in group A、 B1 and C1, 24 h after injured in group B2 and C2, and 48 h after injured in group B3 and C3, Collected the blood samples 5 mL form femoral artery and lung tissue in rats. The levels of tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6)and interleukin-10(IL-10) in serum and malondialdehyde (MDA),myeloperoxidase (MPO) and Superoxide dismutase(SOD) in lung tissue were determined. The lung tissues were examined under microscope. Results The levels of TNF-α、IL-6 and MDA at every phase in group C were lower than those in group B (P0.01),and the SOD and IL-10 were higher (P0.01). Pathology showed thickened alveolar space, inflammatory cells effusion, and local hemorrhage in group B, Inflammatory granulocytes were improved in group C. Conclusion Quercetin has a protective effect on smoke inhalation injured by scavenging free radical and inhibiting proinflammatory cytokines.