title: N-n-butyl Haloperidol Iodide Protects against Hypoxia/Reoxygenation Injury in Cardiac Microvascular Endothelial Cells by Regulating the ROS/MAPK/Egr-1 Pathway.
abstract: Endothelium dysfunction induced by reactive oxygen species (ROS) is an important initial event at the onset of myocardial ischemia/reperfusion in which the Egr-1 transcription factor often serves as a master switch for various damage pathways following reperfusion injury. We hypothesized that an intracellular ROS/MAPK/Egr-1 signaling pathway is activated in cardiac microvascular endothelial cells (CMECs) following hypoxia/reoxygenation (H/R). ROS generation, by either H/R or the ROS donor xanthine oxidase-hypoxanthine (XO/HX) activated all three MAPKs (ERK1/2, JNK, p38), and induced Egr-1 expression and Egr-1 DNA-binding activity in CMECs, whereas ROS scavengers (EDA and NAC) had the opposite effect following H/R. Inhibitors of all three MAPKs individually inhibited induction of Egr-1 expression by H/R in CMECs. Moreover,N-n-butyl haloperidol (F2), previously shown to protect cardiomyocytes subjected to I/R, dose-dependently downregulated H/R-induced ROS generation, MAPK activation, and Egr-1 expression and activity in CMECs, whereas XO/HX and MAPK activators (EGF, anisomycin) antagonized the effects of F2. Inhibition of the ROS/MAPK/Egr-1 signaling pathway, by either F2, NAC, or inhibition of MAPK, increased CMEC viability and the GSH/GSSG ratio, and decreased Egr-1 nuclear translocation. These results show that the ROS/MAPK/Egr-1 signaling pathway mediates H/R injury in CMECs, and F2blocks this pathway to protect against H/R injury and further alleviate myocardial I/R injury.
authors.affiliation: Department of Pharmacy, the First Affiliated Hospital, Shantou University Medical College Shantou, China.
authors.forename: Shishi
authors.initials: S
authors.lastname: Lu
authors.affiliation: Department of Pharmacology, Shantou University Medical College Shantou, China.
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Southern California Los Angeles, CA, USA.
authors.forename: Shuping
authors.initials: S
authors.lastname: Zhong
authors.affiliation: Department of Pharmacology, Shantou University Medical College Shantou, China.
authors.forename: Fenfei
authors.initials: F
authors.lastname: Gao
authors.affiliation: Department of Pharmacology, Shantou University Medical College Shantou, China.
authors.forename: Yicun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Analytical Cytology Laboratory, Shantou University Medical College Shantou, China.
authors.forename: Weiqiu
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Clinical Pharmacology Laboratory, the First Affiliated Hospital, Shantou University Medical College Shantou, China.
authors.forename: Fuchun
authors.initials: F
authors.lastname: Zheng
authors.affiliation: Department of Pharmacology, Shantou University Medical CollegeShantou, China; Department of Cardiovascular Diseases, the First Affiliated Hospital, Shantou University Medical CollegeShantou, China.
authors.forename: Ganggang
authors.initials: G
authors.lastname: Shi
keywords: Egr-1; N-n-butyl haloperidol; cardiac microvascular endothelial cell; hypoxia/reoxygenation; mitogen-activated protein kinase; reactive oxygen species