title: Hypoglycemic Effect of Aquatic Extract of Stevia in Pancreas of Diabetic Rats: PPARγ-dependent Regulation or Antioxidant Potential.
abstract: BACKGROUND
  Traditional medicines with anti-diabetic effects are considered suitable supplements to treat diabetes. Among medicinal herbs, Stevia Rebaudiana Bertoni is famous for its sweet taste and beneficial effect in regulation of glucose. However, little is known about the exact mechanism of stevia in pancreatic tissue. Therefore, this study investigated the possible effects of stevia on pancreas in managing hyperglycemia seen in streptozotocin-induced Sprague-Dawley rats.
  
  
  METHODS
  Sprague-Dawley rats were divided into four groups including normoglycemic, diabetic and two more diabetic groups in which, one was treated with aquatic extract of stevia (400 mg/kg) and the other with pioglitazone (10 mg/kg) for the period of 28 days. After completion of the experimental duration, rats were dissected; blood samples and pancreas were further used for detecting biochemical and histopathological changes. FBS, TG, cholestrol, HDL, LDL, ALT and AST levels were measured in sera. Moreover, MDA (malondialdehyde) level, catalase activity, levels of insulin and PPARγ mRNA expression were also measured in pancreatic tissue.
  
  
  RESULTS
  Aquatic extract of stevia significantly reduced the FBS, triglycerides, MDA, ALT, AST levels and normalized catalase activity in treated rats compared with diabetic rats (p<0.05). In addition to this, stevia surprisingly, increased PPARγ and insulin mRNA levels in treated rats (p<0.05). Furthermore, stevia compensated for the histopathological damage in diabetic rats.
  
  
  CONCLUSIONS
  It is concluded that stevia acts on pancreatic tissue to elevate the insulin level and exerts beneficial anti-hyperglycemic effects through the PPARγ-dependent mechanism and stevia's antioxidant properties.
authors.affiliation: Endocrinology and Metabolism Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Raheleh
authors.initials: R
authors.lastname: Assaei
authors.affiliation: Gasteroenterohepatology Research Center, Nemazee Hospital, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Biochemistry, Faculty of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Pooneh
authors.initials: P
authors.lastname: Mokarram
authors.affiliation: Endocrinology and Metabolism Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran; Department of Biochemistry, Faculty of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Sanaz
authors.initials: S
authors.lastname: Dastghaib
authors.affiliation: Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Darbandi
authors.affiliation: Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.
authors.forename: Mahsa
authors.initials: M
authors.lastname: Darbandi
authors.affiliation: Reproductive Biology Group, Graduate School of Biomedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Zal
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Akmali
authors.affiliation: Endocrinology and Metabolism Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Gholam Hossein
authors.initials: GH
authors.lastname: Ranjbar Omrani
keywords: Diabetes mellitus; Insulin; PPAR gamma; Pancreas; Stevia