title: Tongxinluo inhibits cyclooxygenase-2, inducible nitric oxide synthase, hypoxia-inducible factor-2α/vascular endothelial growth factor to antagonize injury in hypoxia-stimulated cardiac microvascular endothelial cells.
abstract: BACKGROUND
  Endothelial dysfunction is considered as the initiating process and pathological basis of cardiovascular disease. Cyclooxygenase-2 (COX-2) and prostacyclin synthase (PGIS), inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) are key enzymes with opposing actions in inflammation and oxidative stress, which are believed to be the major driver of endothelial dysfunction. And in hypoxia (Hx), Hx-inducible factor (HIF)-1α and HIF-2α are predominantly induced to activate vascular endothelial growth factor (VEGF), resulting in abnormal proliferation. Whether and how Tongxinluo (TXL) modulates COX-2, PGIS, iNOS, eNOS, HIF-1α, HIF-2α, and VEGF in Hx-stimulated human cardiac microvascular endothelial cells (HCMECs) have not been clarified.
  
  
  METHODS
  HCMEC were treated with CoCl 2 to mimic Hx and the mRNA expressions of COX-2, PGIS, iNOS, eNOS, HIF-1α, HIF-2α, and VEGF were first confirmed, and then their mRNA expression and protein content as well as the cell pathological alterations were evaluated for TXL treatment with different concentrations. In addition, the effector molecular of inflammation prostaglandin E 2 (PGE 2 ) and the oxidative marker nitrotyrosine (NT) was adopted to reflect HCMEC injury.
  
  
  RESULTS
  Hx could induce time-dependent increase of COX-2, iNOS, HIF-2α, and VEGF in HCMEC. Based on the Hx-induced increase, TXL could mainly decrease COX-2, iNOS, HIF-2α, and VEGF in a concentration-dependent manner, with limited effect on the increase of PGIS and eNOS. Their protein contents verified the mRNA expression changes, which was consistent with the cell morphological alterations. Furthermore, high dose TXL could inhibit the Hx-induced increase of PGE 2 and NT contents, attenuating the inflammatory and oxidative injury.
  
  
  CONCLUSIONS
  TXL could inhibit inflammation-related COX-2, oxidative stress-related iNOS, and HIF-2α/VEGF to antagonize Hx-induced HCMEC injury.
authors.forename: Yan-Ning
authors.initials: YN
authors.lastname: Li
authors.forename: Xiu-Juan
authors.initials: XJ
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Kun
authors.initials: K
authors.lastname: Liu
authors.affiliation: Department of Molecular Biology, Hebei Key Laboratory of Laboratory Animal, Hebei Medical University, Shijiazhuang, Hebei 050017, China.
authors.forename: Jin-Sheng
authors.initials: JS
authors.lastname: Qi
authors.forename: Bing-Hui
authors.initials: BH
authors.lastname: Liu
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
mesh_terms: D015153:Blotting, Western; D015687:Cell Hypoxia / Q000187:drug effects*; D002460:Cell Line; D003035:Cobalt / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
chemical_list: D004365:Drugs, Chinese Herbal; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; C513941:tongxinluo; D003035:Cobalt; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II