title: Effects and relationship of intermittent hypoxia on serum lipid levels, hepatic low-density lipoprotein receptor-related protein 1, and hypoxia-inducible factor 1α.
abstract: OBJECTIVE
  This study investigated the influence of intermittent hypoxia on serum lipid level, hepatic low-density lipoprotein receptor-related protein (LRP)1, and hepatic hypoxia-inducible factor (HIF)-1α and the underlying mechanisms of action.
  
  
  METHODS
  Male Sprague Dawley rats were subjected to different levels of hypoxia. After 1-4 weeks hypoxemia, routine blood tests were performed and the levels of LRP1 and HIF-1α in liver were examined. Intermittent hypoxia (IH) was induced in HepG2 cells with or without HIF-1α inhibitor YC-1 pretreatment, and the levels of LRP1 and HIF-1α in cells were examined.
  
  
  RESULTS
  IH caused elevated serum triglyceride, cholesterol, low-density lipoprotein, and high-density lipoprotein in rats. IH caused elevated hepatic levels of LRP1 and HIF-1α. After pretreatment with YC-1, HIF-1α protein expression decreased but mRNA expression did not change in HepG2 cells.
  
  
  CONCLUSIONS
  IH caused dyslipidemia and elevated LRP1 and HIF-1α. Elevated LRP1 expression was caused by HIF-1α.
authors.affiliation: Department of Respiratory Medicine, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Anesthesiology, Shengjing Hospital, China Medical University, Shenyang, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Respiratory Medicine, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Respiratory Medicine, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Heping District, Shenyang, China. iziatnas@163.com.
authors.forename: Xue-Wei
authors.initials: XW
authors.lastname: Feng
mesh_terms: D000818:Animals; D015687:Cell Hypoxia / Q000502:physiology*; D056945:Hep G2 Cells; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000097:blood*; D026563:LDL-Receptor Related Protein-Associated Protein / Q000097:blood*; D008055:Lipids / Q000097:blood*; D008099:Liver / Q000503:physiopathology*; D008297:Male; D051381:Rats; D020181:Sleep Apnea, Obstructive / Q000097:blood*
chemical_list: C497444:Hif1a protein, rat; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D026563:LDL-Receptor Related Protein-Associated Protein; D008055:Lipids
keywords: Dyslipidemia; Hypoxia-inducible factor-1α; Intermittent hypoxia; Low-density lipoprotein receptor- related protein 1; YC-1