Preventive and Therapeutic Effects of Quercetin on Experimental Radiation Induced Lung Injury in Mice

Objective: To investigate the protective effect of quercetin on radiation induced lung injury (RILI) andrelated mechanisms. Materials and
Methods: Mice treated with radiation and/or quercetin were sacrificedat 1-8 weeks after irradiation under anesthesia. Lung tissues were collected for histological examination.Immunohistochemistry (IHC) and Western blotting were performed to detect the protein expression of nuclearfactor-κB (NF-κB) and Mitogen-activated protein kinases (MAPK) pathway.
Results: Hematoxylin and eosin (HE)staining showed that radiation controls displayed more severe lung damage than quercetin groups, either highor low dose. Results of IHC and Western blotting demonstrated the expression level of NF-κB to be decreasedand that of an inhibitor of NF-κB (Iκb–α) to be increased by the quercetin intervention compared with theradiation control group. Numbers of JNK/SAPK, p38 and p44/p42 positive inflammatory cells were decreasedin the radiation+quercetin injection group (P<0.05).
Conclusions: Quercetin may play a radio-protective rolein mice lung via suppression of NF-κB and MAPK pathways.