Browsing by Author "Dietrich, Danielle"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Cardioprotective and anti-hypertensive effects of Prosopis glandulosa in rat models of pre-diabetes
    (Clinics Cardive Publishing, 2013) Huisamen, B.; George, C.; Dietrich, Danielle; Genade, S.
    AIM: Obesity and type 2 diabetes present with two debilitating complications, namely, hypertension and heart disease. The dried and ground pods of Prosopis glandulosa (commonly known as the Honey mesquite tree) which is part of the Fabaceae (or legume) family are currently marketed in South Africa as a food supplement with blood glucose-stabilising and anti-hypertensive properties. We previously determined its hypoglycaemic effects, and in the current study we determined the efficacy of P glandulosa as anti-hypertensive agent and its myocardial protective ability. METHODS: Male Wistar rats were rendered either pre-diabetic (diet-induced obesity: DIO) or hypertensive (high-fat diet: HFD). DIO animals were treated with P glandulosa (100 mg/kg/day for the last eight weeks of a 16-week period) and compared to age-matched controls. Hearts were perfused ex vivo to determine infarct size. Biometric parameters were determined at the time of sacrifice. Cardiac-specific insulin receptor knock-out (CIRKO) mice were similarly treated with P glandulosa and infarct size was determined. HFD animals were treated with P glandulosa from the onset of the diet or from weeks 12–16, using captopril (50 mg/kg/day) as the positive control. Blood pressure was monitored weekly. RESULTS: DIO rats and CIRKO mice: P glandulosa ingestion significantly reduced infarct size after ischaemia–reperfusion. Proteins of the PI-3-kinase/PKB/Akt survival pathway were affected in a manner supporting cardioprotection. HFD model: P glandulosa treatment both prevented and corrected the development of hypertension, which was also reflected in alleviation of water retention. CONCLUSION: P glandulosa was cardioprotective and infarct sparing as well as anti-hypertensive without affecting the body weight or the intra-peritoneal fat depots of the animals. Changes in the PI-3-kinase/PKB/Akt pathway may be causal to protection. Results indicated water retention, possibly coupled to vasoconstriction in the HFD animals, while ingestion of P glandulosa alleviated both. We concluded that treatment of pre-diabetes, type 2 diabetes or hypertension with P glandulosa poses possible beneficial health effects.
  • Thumbnail Image
    Item
    Cardiovascular effects of Leonotis leonurus extracts in normotensive rats and in isolated perfused rat heart
    (University of the Western Cape, 2004) Obikeze, Kenechukwu; Dietrich, Danielle; Green, Ivan; Burger, Andreas; School of Pharmacy; Faculty of Science
    This thesis discussed the cardiovascular effects of the aqueous leaf extract and a fraction of the methanol extract of Leonotis leonurus, a plant commonly used in traditional medicine in South Africa for the treatment of hypertension and other cardiac problems. The cardiovascular effects was tested on anaesthetized normotensive male Wistar rats and isolated perfused rat hearts.
  • Thumbnail Image
    Item
    Cardiovascular effects of the alkaloid hippadine on the isolated perfused rat heart
    (Open Access Science Research Publisher, 2012) Mugabo, Pierre; Obikeze, Kenechukwu; Njagi, Angela; Burger, Andries; Dietrich, Danielle; Green, Ivan
    Crinum macowanii has been used extensively in traditional medicines for treatment of various illnesses such as oedema and ‘heart disease’. Previous studies of the crude bulb extracts on Langendorff perfused isolated rat hearts indicated a positive inotropic effect. The aim of this study was to isolate and characterize compound(s) from C. macowanii with cardiovascular effects similar to that observed with the crude extracts of the plant. The methanol extract of dried bulbs was extracted for alkaloids, and structural elucidation of the isolated alkaloid identified it as hippadine. The cardiovascular effects of hippadine was evaluated in vitro in isolated perfused rat hearts using the “double sided” working heart system. Perfusion with 0.5 μg/ml and 5.0 μg/ml hippadine in Krebs-Hanseleit buffer led to significant decreases in coronary flow, aortic output, cardiac output, systolic pressure, and heart rate, accompanied by increases in diastolic pressure. Hippadine exhibited a negative chronotropic and inotropic effect on the isolated rat heart and is responsible either partly or fully for the cardiovascular effects of C. macowanii.