Vitis thunbergii var. taiwaniana Extracts and Purified Compounds Ameliorate Obesity in High-Fat Diet-Induced Obese Mice

Abstract

The increasing prevalence of obesity continues to gain more attention worldwide. In this study, diet-induced obese mice were used to evaluate the antiobesity effects of extracts, fractions, and purified compounds from Vitis thunbergii var. taiwaniana (VTT). The C57BL/6J mice were fed a 5-week high-fat diet (HF) concurrently with ethanol extracts (Et-ext, 80 mg/kg) from roots (R), stems (S), and leaves (L) by oral gavage daily. Only R-Et-ext interventions showed significant weight reduction in mice compared with those in the HF group; however, mouse plasma contents of total cholesterols (TC), total triglycerides (TG) and low-density lipoproteins (LDL) of all three Et-ext intervened groups showed significant reductions compared with those in the HF group. Furthermore, intervention with the ethyl acetate-partitioned fraction (EA-fra, 60 mg/kg) from R-Et-ext but not the n-butanol-partitioned fraction or water fraction from R-Et-ext showed significant weight reduction in mice compared with those in the HF group. The same molecular weights of three resveratrol tetramers, (+)-hopeaphenol, (+)-vitisin A, and (-)-vitisin B, were isolated from the EA-fra of VTT-R. The (+)-vitisin A and fenofibrate (25 mg/kg) but not the (+)-hopeaphenol and (-)-vitisin B interventions showed significant weight reduction in mice compared with those in the HF group. The total feed intake among the HF groups with or without interventions showed no significant differences. The mouse plasma contents of TC, TG, LDL, free fatty acid, and plasma lipase activity of the three resveratrol tetramer-intervened groups showed reductions in the mice compared with those in the HF group. It was proposed that the lipase inhibitory activities of VTT extracts and purified resveratrol tetramers might contribute in part to the antiobesity effect, and these results suggested that VTT may be developed as functional food for achieving antiobesity objectives and requires further investigation.

Vitisin A, a Resveratrol Tetramer, Improves Scopolamine-Induced Impaired Learning and Memory Functions in Amnesiac ICR Mice

“…For the VT-95EE fraction preparations, the 412.3 g VT-95EE was partitioned successively with ethyl acetate (EA) and n -butanol (BuOH) to obtain VT-95EE-EA (83.5 g), VT-95EE-BuOH (117.7 g), and VT-95EE-H 2 O (195.2 g). For crude extracts of different parts of VTT herbal plants, the root (R), stem (S), and leaf (L), were prepared according the previous report [ 32 ]. In brief, the different parts of VTT were dried in an oven at 50 °C for 3 days, powdered, and passed through a 10 mesh sieve (May Chun Co. Ltd., Taichung, Taiwan).…”

“…The isolation and purification of resveratrol tetramers with the same molecular mass of (+)-hopeaphenol, (+)-vitisin A, and (−)-vitisin B from VTT-R-95EE-EA were according to the previous reports [ 32 ]. Briefly, the VTT-R-95EE-EA was separated by a silica gel column (150 cm × 12 cm) and then eluted with increasing polarity of solvent mixtures of n -hexane and EA to obtain twenty-five fractions.…”

“…The (+)-hopeaphenol and (+)-vitisin A were obtained by semi-preparative HPLC from fraction 24E, and (−)-vitisin B was obtained by semi-preparative HPLC from fraction 24F. These three resveratrol tetramers could also be isolated and purified from VTT-R-95EE-EA [ 32 ] or VTT-S-95EE-EA [ 33 ]. The HPLC fingerprinting analysis included two extracts, VT-95EE and VTT-R-95EE, and two partitioned fractions, VT-95EE-EA and VTT-R-95EE-EA.…”

“…The column temperature was kept at room temperature, and the wavelength was set at 280 nm for monitoring. The identified compounds included resveratrol (35.63 min), (+)-hopeaphenol (resveratrol tetramer, 42.07 min), (+)-ampelopsin C (resveratrol trimer, 42.71 min), (+)-ε-viniferin (resveratrol dimer, 46.85 min), (+)-vitisin A (resveratrol tetramer, 50.83 min), and (−)-vitisin B (resveratrol tetramer, 61.01 min) based on the elution sequence [ 31 , 32 , 33 , 34 ].…”

“…The oral administration of VTT-R was shown to reduce the weight gains in one-month high-fat diet-induced obese mice under the same feed intakes. Isolated resveratrol tetramers of (+)-vitisin A might be the active components to reduce the weight gains in 36-day high-fat diet-induced obese mice [ 32 ]. The VTT-S treatments were shown to improve the impaired blood glucose in obese Wistar rats by pre-induction of high-fat diet, which might be via inhibitions against dipeptidyl peptidase IV and α-glucosidase activities [ 33 ].…”