SUBJECTS/METHODS: We used a cross-over designed feeding trial in 53 healthy Asian men and women (20-50 years) to test this hypothesis by exchanging 20% energy of palm olein (PO; control) with randomly interesterified PO (IPO) or high oleic acid sunflower oil (HOS). After a 2-week run-in period on PO, participants were fed PO, IPO and HOS for 6 week consecutively in randomly allocated sequences. Fasting (midpoint and endpoint) and postprandial blood at the endpoint following a test meal (3.54 MJ, 14 g protein, 85 g carbohydrate and 50 g fat as PO) were collected for the measurement of C-peptide, insulin, glucose, plasma glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1, lipids and apolipoproteins; pre-specified primary and secondary outcomes were postprandial changes in C-peptide and plasma glucose.

RESULTS: Low density lipoprotein cholesterol was 0.3 mmol/l (95% confidence interval (95% CI)) 0.1, 0.5; P<0.001) lower on HOS than on PO or IPO as predicted, indicating good compliance to the dietary intervention. There were no significant differences (P=0.58) between diets among the 10 male and 31 female completers in the incremental area under the curve (0-2 h) for C-peptide in nmol.120 min/l: GM (95% CI) were PO 220 (196, 245), IPO 212 (190, 235) and HOS 224 (204, 244). Plasma glucose was 8% lower at 2 h on IPO vs PO and HOS (both P<0.05).

METHODS: The petroleum ether, chloroform and methanol extracts of F. deltoidea were prepared and subjected to standardization using preliminary phytochemical and HPLC analysis. Dose selection was made on the basis of acute oral toxicity study (50-5000 mg/kg b. w.) as per OECD guidelines. Diabetes mellitus was induced with streptozotocin and rats found diabetic were orally administered with the extract (250, 500 and 1000 mg/kg) for 14 days. Levels of blood glucose and insulin were measured in control as well as diabetic rats on 0, 7 and 14th day. In addition, glucose metabolism regulating gene expression was assessed using RT-PCR.