title: Effective antidiabetic and antioxidant fractions of Otostegia persica extract and their constituents.
abstract: BACKGROUND
  Otostegia persica (Burm.) Boiss. (Lamiaceae), "Goldar" in Persian, is widely used in the folk medicine of south Iran for control of diabetes mellitus.
  
  
  OBJECTIVE
  In the present study, hypoglycemic and antioxidant effects of different fractions of the O. persica extract were investigated and constituents of effective fractions were elucidated.
  
  
  METHODS
  Different concentrations (100-400 mg/kg) of aqueous infusion (AI) of flowering aerial parts of the plant (traditional preparation) and all fractions of the O. persica extract (i.p. injection) were tested for antidiabetic activity in streptozocin-induced diabetic NMRI mice. Blood glucose level was measured at time 0 and intervals of 1, 2, 4, and 6 h later. Antioxidant activities of different fractions of the plant extract and pure compounds (0.1, 0.5, and 1 mg/ml) were determined with the DPPH method. Four compounds were isolated and identified from potent fractions.
  
  
  CONCLUSIONS
  Antidiabetic activity demonstrated that the effect of the methanol fraction at a dose of 300 mg/kg was equivalent with glibenclamide, and at a dose of 400 mg/kg was comparable with glibenclamide and insulin (p > 0.05). The EC50 of the methanol fraction was 307.12 mg. Methanol and ethyl acetate fractions showed antioxidant activities (both IC50 equal to 0.49 mg/ml), so these fractions were selected for the purification of compounds. Chrysoeriol from ethyl acetate and three apigenin derivatives (6-methylapigenin, apigenin-7-O-glucoside, and echinaticin) from the methanol fraction were isolated and identified (new for the species). Chrysoeriol exhibited potent antioxidant activity comparable with vitamin E and BHT (p > 0.05).
  
  
  CONCLUSIONS
  The present study confirmed the folklore usage of O. persica for antidiabetic properties.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Medicinal Plant Research Center, Tehran University of Medical Sciences , Tehran , Iran and.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Tofighi
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Alipour
authors.forename: Hormoz
authors.initials: H
authors.lastname: Hadavinia
authors.forename: Mohammad
authors.initials: M
authors.lastname: Abdollahi
authors.forename: Abbas
authors.initials: A
authors.lastname: Hadjiakhoondi
authors.forename: Narguess
authors.initials: N
authors.lastname: Yassa
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D019686:Lamiaceae; D008297:Male; D051379:Mice; D035261:Plant Components, Aerial; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D007004:Hypoglycemic Agents; D010936:Plant Extracts
keywords: Apigenin derivatives; chrysoeriol; hypoglycemic effect; radical scavenging activity