Acetylcholinesterase inhibitory activity and neuroprotection in vitro, molecular docking, and improved learning and memory functions of demethylcurcumin in scopolamine-induced amnesia ICR mice.

In this study, demethylcurcumin (DC), a minor constituent in curcuminoids, showed better anti-acetylcholinesterase (anti-AChE) activities, anti-amyloid ß peptide aggregation, neuroprotective activities in 6-hydroxydopamine-treated SH-SY5Y cell models, and anti-nitric oxide production in lipopolysaccharide-treated RAW 264.7 macrophages than those of curcumin. Based on molecular docking analyses with AChE, the meta-hydroxyl group in DC, nonexistent in curcumin, showed the formation of hydrogen bonds with Ser293 and Tyr341 in the binding sites of AChE. For animal experiments, scopolamine-induced amnesia ICR mice were used to analyze the learning and memory functions of DC in comparison with the positive control donepezil. Mice fed with DC (50 mg kg-1) or donepezil (5 mg kg-1) showed improvement and a significant difference compared to those in the control group (P < 0.05, 0.01, or 0.001) in a passive avoidance test and in a water maze probe test. The brain extracts of the mice in the DC or donepezil group showed reduced AChE activities and higher ORAC activities and also showed a significant difference compared to those in the control group (P < 0.05, 0.01, or 0.001). DC might be beneficial for developing functional foods or as a lead compound for the treatment of degenerative disorders.

Hot-Water Extracts from Roots of Vitis thunbergii var. taiwaniana and Identified ε-Viniferin Improve Obesity in High-Fat Diet-Induced Mice.

In this study, hot-water extracts (HW) from roots of Vitis thunbergii var. taiwaniana (VTT-R) were shown to lower levels of lipid accumulation significantly (P < 0.01 or 0.001) compared to the control in 3T3-L1 adipocytes. The VTT-R-HW (40 mg/kg) interventions concurrent with a high-fat (HF) diet in C57BL/6 mice over a 5 eek period were shown to reduce body weights significantly (P < 0.05) compared to those of mice fed a HF diet under the same food-intake regimen. The (+)-ε-viniferin isolated from VTT-R-HW was shown to reduce the size of lipid deposits significantly compared to the control (P < 0.05 or 0.001) in 3T3-L1 adipocytes, and dose-dependent 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitions showed that the 50% inhibitory concentration was calculated to be 96 µM. The two-stage (+)-ε-viniferin interventions (10 mg/kg, day 1 to day 38; 25 mg/kg, day 39 to day 58) were shown to lower mice body weights significantly (P < 0.05 or 0.001), the weight ratio of mesenteric fat, blood glucose, total cholesterol, and low-density lipoprotein compared to that of the HF group under the same food-intake regimen but without concurrent VTT-R-HW interventions. It might be possible to use VTT-R-HW or (+)-ε-viniferin as an ingredient in the development of functional foods for weight management, and this will need to be investigated further.

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

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.