title: [Quercetin protects against lipopolysaccharide-induced cardiac injury in mice].
abstract: OBJECTIVE
  To evaluate the protective effect of quercetin against lipopolysaccharide (LPS)-induced cardiac injury in mice.
  
  
  METHODS
  C57BL/6J mice were randomized into 4 groups to receive intraperitoneal injection of saline (negative control) or LPS (20 mg/kg), or fed with quercetin (100 mg/kg for 7 days) with or without subsequent LPS injection (quercetin+LPS group and quercetin control group, respectively). Six hour after LPS injection, the mice were tested for cardiac function with an echocardiograph, and the protein expressions of Bax, Bcl-2, iNOS, and eNOS in the myocardium were evaluated with Western blotting; serum NO concentration was also measured. The survival of the mice within 5 days after LPS injection was recorded to draw the survival curve.
  
  
  RESULTS
  Quercetin pretreatment significantly improved the cardiac function of LPS-challenged mice (P<0.05), and attenuated LPS-induced increment in myocardial iNOS expression and decrement in eNOS level. LPS significantly increased the myocardial Bax expression and slightly decreased Bcl-2 expression; quercetin pretreatment decreased Bax expression to the control level and significantly lowered Bax/Bcl-2 ratio as compared with the LPS group. Serum NO level was significantly increased by nearly 2.5 folds in LPS-challenged mice, but was markedly decreased with quercetin pretreatment (P<0.05). The 5-day survival rate of LPS-treated mice was 10%, which was increased to 45% in quercetin- pretreated mice (P<0.05).
  
  
  CONCLUSIONS
  Quercetin can alleviate LPS-induced cardiac dysfunctions in mice to increase their survival rate following LPS challenge.
authors.affiliation: Department of Basic Medicine, Xiangnan College of Medicine, Hunan Province, Chenzhou 423000, China.E-mail: okleonlj@163.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Xinmin
authors.initials: X
authors.lastname: Dong
authors.forename: Huafei
authors.initials: H
authors.lastname: Deng
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
mesh_terms: D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D008070:Lipopolysaccharides / Q000009:adverse effects; D051379:Mice; D008810:Mice, Inbred C57BL; D009206:Myocardium / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011794:Quercetin / Q000494:pharmacology*
chemical_list: D002316:Cardiotonic Agents; D008070:Lipopolysaccharides; D019253:Proto-Oncogene Proteins c-bcl-2; C052617:Bcl2 protein, mouse; D011794:Quercetin; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496317:Nos2 protein, mouse; C496315:Nos3 protein, mouse