title: Amlodipine protects rat ventricular cardiomyoblast H9c2 From hypoxia-induced apoptosis and restores oxidative balance by Akt-1-dependent manner.
abstract: BACKGROUND
  Hypoxia-induced rise in intracellular calcium concentration is a causative agent of apoptosis and oxidative damage in cardiomyocytes. We examined the efficacy of calcium channel blocker amlodipine in preventing hypoxia-induced apoptosis in H9c2 cells and restoring oxidative balance.
  
  
  METHODS
  H9c2 cells were exposed to hypoxia (0.5% oxygen) to evaluate the efficacy of amlodipine in restoring cellular calcium levels. Cellular markers of apoptosis (Bax/Bcl2 and caspase-3, -7, and -9) and pro-survival markers (Akt/p-Akt levels) were evaluated under hypoxia. Redox damage was evaluated by assessing markers of oxidative damage, that is, glutathione reduced, glutathione oxidized, lipid peroxidation, reactive oxygen species, and manganese superoxide dismutase activity. Cellular adenosine triphosphate (ATP) pool and AMPKα levels were measured to evaluate regulation of metabolism under hypoxia.
  
  
  RESULTS
  Amlodipine treatment at 25 nM prevented apoptosis and restored cellular calcium levels and oxidative damage in cardiomyocytes. Stabilization of caspase-3, -7, and -9 along with restoration of Akt/p-Akt levels depicted pro-survival efficacy of amlodipine. Also, restoration of cellular ATP and AMPKα levels indicates that amlodipine prevents cardiomyocytes from hypoxia-induced metabolic stress.
  
  
  CONCLUSIONS
  Amlodipine thus protects H9c2 cells from hypoxia-induced apoptosis by regulating Akt/p-Akt-mediated caspase-3, -7, and -9 activation and restoring cellular ATP and redox status.
authors.affiliation: *Defence Research and Development Organization, New Delhi, India; and †Department of Experimental Biology, Defence Institute of Physiology and Allied Science.
authors.forename: Sarita
authors.initials: S
authors.lastname: Nehra
authors.forename: Varun
authors.initials: V
authors.lastname: Bhardwaj
authors.forename: Deepika
authors.initials: D
authors.lastname: Saraswat
mesh_terms: D017311:Amlodipine / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015687:Cell Hypoxia / Q000187:drug effects; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D015227:Lipid Peroxidation / Q000187:drug effects; D032386:Myoblasts, Cardiac / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats
chemical_list: D002121:Calcium Channel Blockers; D017311:Amlodipine; D051057:Proto-Oncogene Proteins c-akt; D002118:Calcium