Food Industry Research & Development Institute | Date: 2011-04-29
Chao P.-M.,China Medical University at Taichung |
Kuo Y.-H.,China Medical University at Taichung |
Kuo Y.-H.,National Taiwan University |
Kuo Y.-H.,Academia Sinica, Taiwan |
And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
Inhibition of acetyl-CoA carboxylase (ACC) is one approach used for treating metabolic syndrome. Using partially purified ACC to screen herbs commonly used in Taiwanese folk medicine, we previously showed that an ethanol extract of Polygonum hypoleucum Ohwi (EP) had potent ACC inhibitory activity and partially alleviated metabolic disorders induced by a high fat diet. Since ACC plays a crucial role in de novo lipogenesis, the favorable effects of EP on metabolism were tested under lipogenic conditions in the present study. On incubating high glucose (30 mM)-stimulated HepG2 cells with EP (72.5 or 145 μg/mL), ACC and fatty acid synthase activity, triacylglycerol content, and microsomal triacylglycerol transfer protein mRNA levels were all significantly reduced (P < 0.05, vs vehicle). When EP was given at low, medium, and high dosages (94, 188, and 470 mg/kg) to sucrose water-treated Wistar rats for four weeks, alleviation of symptoms associated with metabolic syndrome, including obesity, insulin resistance, hypertriglyceridemia, and hypertension, accompanied by hepatic ACC inactivation, was seen in the low dosage group. Four compounds (emodin, emodin-8-O-β-d-glucopyranoside, (+)-catechin, and (-)-epicatechin) isolated from EP were identified as ACC inhibitors. These results confirm that P. hypoleucum Ohwi, acting partly through ACC inhibition, has favorable effects in alleviating metabolic disturbances occurring under lipogenic conditions. © 2010 American Chemical Society.
Wang R.,National Taiwan University of Science and Technology |
Lin P.-Y.,Joint Center for Instruments and Researches |
Huang S.-T.,Food Industry Research Development Institute |
Chiu C.-H.,National Taiwan University of Science and Technology |
And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2015
Bacteria and fungi can secrete extracellular enzymes to convert macromolecules into smaller units. Hyperproduction of extracellular enzymes is often associated with alterations in cell wall structure in fungi. Recently, we identified that Saccharomyces cerevisiae kre6Δ mutants can efficiently convert mogroside V into mogroside III E, which has antidiabetic properties. However, the underlying efficient bioconversion mechanism is unclear. In the present study, the mogroside (MG) bioconversion properties of several cell wall structure defective mutants were analyzed. We also compared the cell walls of these mutants by transmission electron microscopy, a zymolyase sensitivity test, and a mannoprotein release assay. We found zymolyase-sensitive mutants (including kre1Δ, las21Δ, gas1Δ, and kre6Δ), with defects in mannoprotein deposition, exhibit efficient MG conversion and excessive leakage of Exg1; such defects were not observed in wild-type cells, or mutants with abnormal levels of glucans in the cell wall. Thus, yeast mutants defective in mannoprotein deposition may be employed to convert glycosylated bioactive compounds. © 2015 American Chemical Society.
Chen G.-C.,China Medical University at Taichung |
Huang C.-Y.,China Medical University at Taichung |
Chang M.-Y.,China Medical University at Taichung |
Chen C.-H.,Food Industry Research Development Institute |
And 3 more authors.
Metabolism: Clinical and Experimental | Year: 2011
To establish animal models with diet-induced metabolic disorders similar to human metabolic syndrome, 2 unhealthy dietary habits featuring a high fat content and a sucrose-containing beverage intake, alone or in combination, were tested on Wistar rats and C57BL/6J mice. The 2 dietary habits were, respectively, simulated by feeding a high-fat diet (regimen A) or additionally providing 30% sucrose (wt/vol) in the drinking water (regimen B). Using a 2 × 2 factorial design, 4 groups of animals were fed chow diet plus plain water (group C), high-fat diet (30% [wt/wt] fat) plus plain water (group A), chow diet plus sucrose in drinking water (group B), and high-fat diet plus sucrose in drinking water (group AB) for 26 weeks. In Wistar rats, regimen B caused a significant increase in visceral fat; serum levels of lipids, glucose, insulin, and uric acid; insulin resistance; and blood pressure, whereas regimen A only caused a significant increase in visceral fat and serum insulin levels (P < .05). In contrast, regimen A induced a full array of metabolic syndrome in C57BL/6J mice; but regimen B only caused slight obesity and hyperlipidemia. In both Wistar rats and C57BL/6J mice, there were no additive effects of the 2 regimens, indicated by significant interactions between regimens A and B on the metabolic indexes measured. These results show that, in terms of inducing metabolic syndrome, Wistar rats are more responsive to sucrose water regimen, whereas C57BL/6J mice are more responsive to the high-fat diet regimen. © 2011 Elsevier Inc. All rights reserved.