Reducing Effect of a Combination of Phaseolus vulgaris and Cynara scolymus Extracts on Food Intake and Glycemia in Rats

Extracts from Phaseolus vulgaris and Cynara scolymus may reduce food intake and/or postprandial glycemia. This study investigated the effect of standardized extracts of P. vulgaris and C. scolymus and their combination on food intake and glycemia in rats. P. vulgaris and C. scolymus extracts, and their 1:2 combination, were administered acutely to rats (a) given access to regular food and water, (b) given access to regular food, water, and a chocolate‐flavored beverage, or (c) infused with a starch bolus. P. vulgaris extract and the combination produced comparable reductions in intake of regular food and chocolate‐flavored beverage; conversely, C. scolymus extract was ineffective on both parameters. P. vulgaris and C. scolymus extracts additively contributed to the reducing effect of the combination on glycemic rise. These results suggest that a mixture of P. vulgaris and C. scolymus extracts is preferable over each single extract, as it combines the anorectic effect of the P. vulgaris extract with the hypoglycemic effect of both extracts. These data support the recent clinical use of the combination of P. vulgaris and C. scolymus extracts in the control of appetite, food intake, and postprandial glycemia and represent a successful example of translational research in the nutraceutical field. Copyright © 2012 John Wiley & Sons, Ltd.     

Appetite Control and Glycaemia Reduction in Overweight Subjects treated with a Combination of Two Highly Standardized Extracts from Phaseolus vulgaris and Cynara scolymus

The management of overweight may include the use of dietary supplements targeted to favour the increase of the satiation associated with a decrease in blood glucose and lipid levels. The aim of this study was to evaluate the efficacy of a dietary supplementation with an extract from Phaseolus vulgaris and Cynara scolymus, on satiation, the glucose and lipid pattern. A randomized, double‐blind, placebo‐controlled clinical trial was performed in 39 overweight subjects (20 supplemented group, 19 placebo group) for 2 months. The modification of satiation, by Haber's scale, was the primary end‐point, and the variation of the glucose and lipid pattern, of the anthropometric parameters and of the psychodynamic tests score were the secondary end‐points. At the end of treatment, the net change of the Haber's mean score increased significantly in the intervention group. The net change of the glycaemia and of the dietary restriction score of the three factor eating questionnaire (TFEQ), were reduced significantly only in the intervention group. Moreover, in the supplemented group, the homeostasis model assessment, the body mass index and the susceptibility‐to‐hunger score of the TFEQ, decreased significantly after intervention; these parameters did not change in the controls. This treatment appears potentially useful in the management of overweight and dysglycaemia. Copyright © 2011 John Wiley & Sons, Ltd.     

Evidence of glycemia‐lowering effect by a Cynara scolymus L. extract in normal and obese rats

Several recent preliminary clinical studies have suggested that artichoke (Cynara scolymus L., Asteraceae family) preparations may be capable of lowering post‐prandial glycemia. The present study was designed to test this hypothesis in laboratory rats. To this aim, non‐selected Wistar and genetically obese Zucker rats were treated acutely with a purified extract of Cynara scolymus flowering heads (500–1500 mg/kg by gavage) immediately prior to 1 h access to a fixed amount of food. Glycemia was recorded 60, 120 and 360 min after food presentation. Treatment with Cynara scolymus flowering head extract resulted in a significant decrease of post‐prandial glycemia in both rat strains. The lack of any fiber content in this Cynara scolymus flowering head extract excludes the involvement of dietary fibers in glycemia reduction. The results obtained constitute the first evidence of a hypoglycemic effect of an artichoke preparation in laboratory rodents and confirm previous observations made in humans. Copyright © 2010 John Wiley & Sons, Ltd.     

Effect of Fucoxanthin Alone and in Combination with D‐glucosamine Hydrochloride on Carrageenan/kaolin‐induced Experimental Arthritis in Rats

The objective of the present study was to investigate the effect of the fucoxanthin (FUCO) alone and in combination with glucosamine hydrochloride (GAH) on carrageenan/kaolin‐induced inflammatory arthritis model in rats and to explore its underlying mechanisms. Joint swelling, muscle weight ratio (%), histopathological examination and scoring, and proteoglycan degradation were examined. Pro‐inflammatory interleukin (IL‐1β) and tumor necrosis (TNF‐α) levels, cyclooxygenase‐2 (COX‐2), and inducible nitric oxide synthase(iNOS) protein expression and nitric oxide (NO) level in knee synovial tissue extract were analyzed using enzyme‐linked immunosorbent assay, western blotting analysis, and Griess reagent assay, respectively. FUCO and FUCO + GAH not only may significantly reduce degrees of knee joint swelling and prevent against muscle atrophy, but also may significantly attenuate inflammation in synovial tissue, cartilage erosion, and proteoglycan loss. The efficacies of FUCO + GAH were stronger than that of GAH or FUCO. FUCO alone and FUCO + GAH can significantly inhibit upregulation of COX‐2 and iNOS protein expressions, decrease of IL‐1β and TNF‐α levels, and reduce NO production in knee synovial tissue extract. These results indicated that FUCO is an effective anti‐arthritis agent through an antiinflammation mechanism. FUCO may enhance therapeutic effect of GAH on rat arthritis through mechanism of antiinflammation. Copyright © 2013 John Wiley & Sons, Ltd.