Protective effect of quercetin on acute lung injury in rats with sepsis and its influence on ICAM-1 and MIP-2 expression

This study aimed to explore the protective effect of quercetin on acute lung injury (ALI) in rats with sepsis and the related mechanism. Rats were administered different doses of quercetin intraperitoneally, and blood samples and lung tissue were collected at 24 h after treatment. Arterial blood gases, lung water content, protein content, and cell counts in bronchoalveolar lavage fluid (BALF) were measured. Morphological changes in lung tissue pathology were observed under a light microscope. Serum intercellular adhesion molecule (ICAM)-1 and macrophage inflammatory protein 2 (MIP-2) levels were detected and ICAM-1 and MIP-2 mRNA expression in lung tissue was determined. Compared with that in the control model group, arterial blood gases, lung water content, protein content, and cell counts in BALF improved in the high- and low-dose quercetin groups (P < 0.05), with maximal improvement observed for the high-dose quercetin (P < 0.05). Lesions on the lungs improved in the high- and low-dose quercetin groups than those in the control model group, and the high-dose quercetin group showed better improvement than the low-dose group (P < 0.05). Compared with that in the sham-operated group, both serum and lung tissue ICAM-1 and MIP-2 expression increased significantly in the model group (P < 0.05). The quercetin groups presented lower ICAM-1 and MIP-2 expression than the control model group, with the lowest expression observed in the high-dose group (P < 0.05). Quercetin may protect against ALI in rats with sepsis by inhibiting ICAM-1 and MIP-2 expression.