Effects of quercetin on bleomycin-induced lung injury: a preliminary study
To investigate the effects of quercetin in a model of bleomycin-induced pulmonary inflammation and fibrosis.



Seventynine adult male hamsters were randomized to receive intratracheal (IT) instillations and intraperitoneal (IP) injections in four configurations: IP vehicle/IT saline (VS group, n = 16); IP quercetin/IT saline (QS group, n = 16); IP vehicle/IT bleomycin (VB group, n = 27); and IP quercetin/ IT bleomycin (QB group, n = 20). Quercetin and bleomycin were administered at 30 mg/kg/day and 10 U/kg, respectively. Quercetin was started/discontinued 3 days before/14 days after the IT instillations.



The mortality rate was significantly higher in the VB group than in the other groups (44% vs. VS: 0%; QS: 0%; and QB: 15%). Lung levels of thiobarbituric acid reactive substances (× 10−2 nmol/mg) were significantly higher in the VB group (6.6 ± 1.3 vs. VS: 5.5 ± 0.8; QS: 2.5 ± 0.6; and QB: 5.8 ± 0.6). Lung levels of reduced glutathione (× 10−2 nmol/mg) were significantly lower in the VB/QB groups than in the VS/QS groups (28.9 ± 13.8/28.6 ± 14.8 vs. 43.9 ± 16.0/51.1 ± 20.3), whereas those of hydroxyproline (mg/g) were significantly higher (201.6 ± 37.3/177.6 ± 20.3 vs. 109.6 ± 26.1/117.5 ± 32.0).Mean lung septal thickness (µm) was greatest in the VB group (16.9 ± 3.2 vs. VS: 3.0 ± 0.3; QS: 3.3 ± 0.2; and QB: 5.2 ± 1.1).



In a hamster model of lung injury, quercetin exhibited anti-inflammatory effects that are related, at least in part, to its antioxidant properties. Keywords: Pulmonary fibrosis; Bleomycin; Flavonoids; Lipid peroxidation.
Martinez
José Antônio Baddini
JA
Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil. jabmarti@fmrp.usp.br
Ramos
Simone Gusmão
SG
Meirelles
Mônica Souza
MS
Verceze
Adalberto Valladas
AV
Arantes
Maurício Rodrigues de
MR
Vannucchi
Hélio
H
D000704:Analysis of Variance; D000818:Animals; D000903:Antibiotics, Antineoplastic; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D001761:Bleomycin; D003094:Collagen / Q000378:metabolism; D006224:Cricetinae; D004195:Disease Models, Animal; D015227:Lipid Peroxidation / Q000187:drug effects; D008168:Lung / Q000187:drug effects / Q000473:pathology; D055370:Lung Injury / Q000139:chemically induced / Q000517:prevention & control*; D008297:Male; D008647:Mesocricetus; D018384:Oxidative Stress / Q000187:drug effects*; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D011794:Quercetin / Q000008:administration & dosage / Q000627:therapeutic use*; D011897:Random Allocation
D000903:Antibiotics, Antineoplastic; D000975:Antioxidants; D001761:Bleomycin; D003094:Collagen; D011794:Quercetin