title: Extract from Mimosa pigra attenuates chronic experimental pulmonary hypertension.
abstract: BACKGROUND
  Different parts of Mimosa pigra (MPG) are used in traditional medicine in Madagascar, tropical Africa, South America and Indonesia for various troubles including cardiovascular disorders.
  
  
  OBJECTIVE
  To investigate the mechanisms underlying the vascular effects of MPG by assessing in vitro its antioxidant and anti-inflammatory properties, and its vascular relaxing effects, and in vivo, its action on hypoxic pulmonary hypertension (PAH) in rats.
  
  
  METHODS
  The antioxidant activity of MPG leaf hydromethanolic extract was determined by using both the 1,1-diphenyl-2-picrylhydrazyl radical scavenging and the oxygen radical absorbance capacity in vitro assays. Anti-inflammatory properties were assayed on TNFα-induced VCAM-1 expression in endothelial cells. The vasorelaxant effect of MPG extract was studied on rat arterial rings pre-contracted with phenylephrine (1μM) in the presence or absence of the endothelium. In vivo MPG extract effects were analyzed in chronic hypoxic PAH, obtained by housing male Wistar rats, orally treated or not with MPG extract (400mg/kg/d), in a hypobaric chamber for 21 days.
  
  
  RESULTS
  MPG leaf extract had antioxidant and anti-inflammatory properties. It induced endothelium-dependent, NO-mediated relaxation of rat aorta and pulmonary artery. In vivo, chronic MPG treatment reduced hypoxic PAH in rat by decreasing by 22.3% the pulmonary arterial pressure and by 20.0% and 23.9% the pulmonary artery and cardiac remodelling, respectively. This effect was associated with a restoration of endothelium function and a 2.3-fold increase in endothelial NO synthase phosphorylation. MPG leaf hydromethanolic extract contained tryptophan and flavonoids, including quercetin glycosides. Both compounds also efficiently limit hypoxia-induced PAH.
  
  
  CONCLUSIONS
  Our results show endothelial protective action of MPG leaf hydromethanolic extract which is likely to be due to its antioxidant action. MPG successfully attenuated the development of PAH, thus demonstrating the protective effect of MPG on cardiovascular diseases.
authors.affiliation: INSERM, UMR_S1087-CNRS UMR_C6291, Nantes, F-44000 France; Université de Nantes, Nantes, F-44000 France.
authors.forename: G
authors.initials: G
authors.lastname: Rakotomalala
authors.forename: C
authors.initials: C
authors.lastname: Agard
authors.forename: P
authors.initials: P
authors.lastname: Tonnerre
authors.forename: A
authors.initials: A
authors.lastname: Tesse
authors.forename: S
authors.initials: S
authors.lastname: Derbré
authors.forename: S
authors.initials: S
authors.lastname: Michalet
authors.forename: J
authors.initials: J
authors.lastname: Hamzaoui
authors.forename: M
authors.initials: M
authors.lastname: Rio
authors.forename: C
authors.initials: C
authors.lastname: Cario-Toumaniantz
authors.forename: P
authors.initials: P
authors.lastname: Richomme
authors.forename: B
authors.initials: B
authors.lastname: Charreau
authors.forename: G
authors.initials: G
authors.lastname: Loirand
authors.forename: P
authors.initials: P
authors.lastname: Pacaud
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D002316:Cardiotonic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002478:Cells, Cultured; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D017380:Hypertrophy, Right Ventricular / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D000860:Hypoxia / Q000150:complications; D066298:In Vitro Techniques; D008297:Male; D031298:Mimosa; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018515:Plant Leaves; D011651:Pulmonary Artery / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D014665:Vasodilator Agents / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D002316:Cardiotonic Agents; D010936:Plant Extracts; D014665:Vasodilator Agents