title: Inhibition of glucose-induced vascular endothelial growth factor expression by Salvia miltiorrhiza hydrophilic extract in human microvascular endothelial cells: evidence for mitochondrial oxidative stress.
abstract: OBJECTIVE
  Diabetes mellitus is frequently combined with vascular diseases, which are associated with the expression of vascular endothelial growth factor (VEGF). An approach that can reverse the induction of VEGF by hyperglycemia may potentially benefit the outcome of diabetic patients. Therefore, in the present study, we investigated the effect of Salvia miltiorrhiza (S. miltiorrhiza) hydrophilic extract on the expression of VEGF induced by high concentration of glucose.
  
  
  METHODS
  Vector of VEGF promoter luc was transiently transfected into HMEC-1 cells, and luciferase activity was measured to determine the promoter activity. In order to investigate the mechanism of Salvia miltiorrhiza hydrophilic extract, mitochondrial uncoupling protein 2(UCP2) was knockdown by using UCP2 siRNA. The expression of VEGF was obtained by using quantitative RT-PCR and dot blot. The level of reactive oxygen species (ROS) was expressed by the level of 2',7'-dichlorfluorescein.
  
  
  RESULTS
  Exposure of HMEC-1 cells to 30 mM glucose resulted in a significant increase in the expression of VEGF mRNA (5.7 fold at 3mM glucose, P<0.005), and an increase of ROS formation (2.4 fold at 3mM glucose, P<0.005). These effects were completely antagonized by an inhibitor of electron transport chain complex II, thenoyltrifluoroacetone (TTFA) and an uncoupler of oxidative phosphorylation, carbonylcyanide-m-chlorophenylhydrazone (CCCP). Addition of Salvia miltiorrhiza hydrophilic extract (10 μg/ml) led to a significant decrease of VEGF mRNA and ROS formation in 30 mM glucose condition. Interestingly, knockdown of mitochondrial UCP-2 by UCP-2 siRNA abolished the reduction of VEGF expression and ROS formation by Salvia miltiorrhiza hydrophilic extract.
  
  
  CONCLUSIONS
  These findings indicated that Salvia miltiorrhiza hydrophilic extract effectively reversed induction of VEGF expression by high glucose via ameliorating mitochondrial oxidative stress. Salvia miltiorrhiza hydrophilic extract can potentially be an effective antioxidant therapy for the treatment of diabetic chronic vascular complication.
authors.affiliation: Department of Clinical Laboratory, 1st Affiliated Hospital, Zhengzhou University, Zhengzhou 450052, China.
authors.forename: Shuhong
authors.initials: S
authors.lastname: Qian
authors.forename: Dongxia
authors.initials: D
authors.lastname: Huo
authors.forename: Shijin
authors.initials: S
authors.lastname: Wang
authors.forename: Qingwen
authors.initials: Q
authors.lastname: Qian
mesh_terms: D001892:Camphanes; D018929:Cell Culture Techniques; D002460:Cell Line; D003925:Diabetic Angiopathies / Q000378:metabolism / Q000517:prevention & control; D004365:Drugs, Chinese Herbal / Q000302:isolation & purification / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007473:Ion Channels / Q000037:antagonists & inhibitors / Q000235:genetics; D055806:Microvessels / Q000166:cytology / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D010085:Oxidative Phosphorylation; D018384:Oxidative Stress / Q000187:drug effects*; D053723:Panax notoginseng; D034741:RNA, Small Interfering / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D027561:Salvia miltiorrhiza / Q000737:chemistry*; D014162:Transfection; D000071246:Uncoupling Protein 2; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors* / Q000235:genetics
chemical_list: D001892:Camphanes; D004365:Drugs, Chinese Herbal; D007473:Ion Channels; D024101:Mitochondrial Proteins; D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; C000604389:UCP2 protein, human; D000071246:Uncoupling Protein 2; D042461:Vascular Endothelial Growth Factor A; C000604051:danshen dripping pill; D005947:Glucose