Vitis Thunbergii Research Articles

Vitisin B, a resveratrol tetramer from Vitis thunbergii var. taiwaniana, ameliorates impaired glucose regulations in nicotinamide/streptozotocin-induced type 2 diabetic mice.

In Taiwan, Vitis thunbergii var. taiwaniana (VTT) is used in traditional medicine and as a local tea. VTT rich in resveratrol and resveratrol oligomers have been reported to exhibit anti-obesity and anti-hypertensive activities in animal models; however, no studies have investigated type 2 diabetes mellitus (T2DM) treatments. This study aimed to investigate the anti-T2DM effects of resveratrol tetramers isolated from the VTT in nicotinamide/streptozotocin (STZ)-induced Institute of Cancer Research (ICR) mice. The oral glucose tolerance test (OGTT) was used to imitate postprandial blood glucose (BG) regulations in mice by pre-treatment with VTT extracts, resveratrol tetramers of vitisin A, vitisin B, and hopeaphenol 30min before glucose loads. Vitisin B (50mg/kg) was administered to treat T2DM-ICR mice once daily for 28 days to investigate its hypoglycemic activity. Mice pre-treated with VTT-S-95EE, or vitisin B (100mg/kg) 30-min before glucose loading showed significant reductions (P<0.001) in the area under the curve at 120-min (BG-AUC0-120) than those without pre-treatment with VTT-S-95EE or vitisin B. Vitisin B-treated T2DM mice showed hypoglycemic activities via a reduction in plasma dipeptidyl peptidase (DPP)-IV activities to maintain insulin actions and differed significantly than those of untreated T2DM mice (P<0.05), and also reduced BG-AUC0-120 and insulin-AUC0-120 in the OGTT.These invivo results showed that VTT containing vitisin B would be beneficial for developing nutraceuticals and/or functional foods for glycemic control in patients with T2DM, which should be investigated further.

Anti-Inflammatory Effect of Resveratrol Derivatives via the Downregulation of Oxidative-Stress-Dependent and c-Src Transactivation EGFR Pathways on Rat Mesangial Cells.

In Taiwan, the root extract of Vitis thunbergii Sieb. et Zucc. (Vitaceae, VT) is rich in stilbenes, with resveratrol (Res) and its derivatives being the most abundant. Previously, we showed that the effect of Res derivatives against tumor necrosis factor-α (TNF-α)-stimulated inflammatory responses occurs via cPLA2/COX-2/PGE2 inhibition. This study compared and explored the underlying anti-inflammatory pharmacological mechanisms. Before stimulation with TNF-α, RMCs were treated with/without pharmacological inhibitors of specific protein kinases. The expression of inflammatory mediators was determined by Western blotting, gelatin zymography, real-time PCR, and luciferase assay. Cellular and mitochondrial ROS were measured by H2DHFDA or DHE and MitoSOX™ Red staining, respectively. The RNS level was indirectly measured by Griess reagent assay. Kinase activation and association were assayed by immunoprecipitation followed by Western blotting. TNF-α binding to TNFR recruited Rac1 and p47phox, thus activating the NAPDH oxidase-dependent MAPK and NF-κB pathways. The TNF-α-induced NF-κB activation via c-Src-driven ROS was independent from the EGFR signaling pathway. The anti-inflammatory effects of Res derivatives occurred via the inhibition of ROS derived from mitochondria and NADPH oxidase; RNS derived from iNOS; and the activation of the ERK1/2, JNK1/2, and NF-κB pathways. Overall, this study provides an understanding of the various activities of Res derivatives and their pharmacological mechanisms. In the future, the application of the active molecules of VT to health foods and medicine in Taiwan may increase.

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

Resveratrol has been reported to exhibit neuroprotective activities in vitro and in vivo. However, little is known about resveratrol tetramers of hopeaphenol, vitisin A, and vitisin B with the same molecular mass in the improvement of degenerative disorders. In this study, two 95% ethanol extracts (95EE) from stem parts of Vitis thunbergii Sieb. & Zucc. (VT-95EE) and from the root (R) parts of Vitis thunbergii var. taiwaniana (VTT-R-95EE) showed comparable acetylcholinesterase (AChE) inhibitory activities. It was found that VT-95EE and VTT-R-95EE showed different distribution patterns of identified resveratrol and resveratrol tetramers of hopeaphenol, vitisin A, and vitisin B based on the analyses of HPLC chromatographic profiles. The hopeaphenol, vitisin A, and vitisin B, showed AChE and monoamine oxidase-B inhibitions in a dose-dependent manner, among which vitisin B and vitisin A exhibited much better activities than those of resveratrol, and had neuroprotective activities against methylglyoxal-induced SH-SY5Y cell deaths. The scopolamine-induced amnesiac ICR mice treated with VT-95EE and its ethyl acetate-partitioned fraction (VT-95EE-EA) at doses of 200 and 400 mg/kg, or vitisin A at a dose of 40 mg/kg, but not vitisin B (40 mg/kg), were shown significantly to improve the impaired learning behaviors by passive avoidance tests compared to those in the control without drug treatments (p < 0.05). Compared to mice in the control group, the brain extracts in the vitisin A-treated mice or donepezil-treated mice showed significant reductions in AChE activities and malondialdehyde levels (p < 0.05), and elevated the reduced protein expressions of brain-derived neurotrophic factor (BDNF) and BDNF receptor, tropomyosin receptor kinase B (TrkB). These results revealed that vitisin A was the active constituent in the VT-95EE and VTT-95EE, and the VT medicinal plant and that the endemic variety of VTT has potential in developing functional foods for an unmet medical need for neurodegenerative disorders.

The anti-inflammatory effect of ε-viniferin by specifically targeting formyl peptide receptor 1 on human neutrophils

The uncontrol respiratory burst in neutrophils can lead to inflammation and tissue damage. This study investigates the effect and the underlying mechanism of ε-viniferin, a lignan from the root of Vitis thunbergii var. thunbergii, inhibits N-formyl-L-methionyl-L-leucyl-l-phenylalanine (fMLP) induced respiratory burst by antagonizing formyl peptide receptor 1 in human neutrophils. Briefly, ε-viniferin specifically inhibited fMLP (0.1 μM: formyl peptide receptor 1 agonist or 1 μM: formyl peptide receptor 1, 2 agonist)-induced superoxide anion production in a concentration-dependent manner (IC50 = 2.30 ± 0.96 or 9.80 ± 0.21 μM, respectively) without affecting this induced by formyl peptide receptor 2 agonist (WKYMVM). ε-viniferin inhibited fMLP (0.1 μM)-induced phosphorylation of ERK, Akt, Src or intracellular calcium mobilization without affecting these caused by WKYMVM. The synergistic suppression of fMLP (1 μM)-induced superoxide anion production was observed only in the combination of ε-viniferin and formyl peptide receptor 2 antagonist (WRW4) but not in combination of ε-viniferin and formyl peptide receptor 1 antagonist (cyclosporine H). ε-viniferin inhibited FITC-fMLP binding to formyl peptide receptors. Moreover, the synergistic suppression of FITC-fMLP binding was observation only in the combination of ε-viniferin and WRW4 but not in other combinations. ATPγS induced superoxide anion production through formyl peptide receptor 1 in fMLP desensitized neutrophils and this effect was inhibited by ε-viniferin. The concentration-response curve of fMLP-induced superoxide anion was not parallel shifted by ε-viniferin. Furthermore, the inhibiting effect of ε-viniferin on fMLP-induced superoxide anion production was reversible. These results suggest that ε-viniferin is an antagonist of formyl peptide receptor 1 in a reversible and non-competitive manner.

Antioxidant Properties of Extracts from Medicinal Plants Popularly Used in Taiwan

We have examined antioxidant activities of twenty-six medicinal herbal extracts that have been popularly used as folk medicines in Taiwan. The results of scavenging DPPH radical activity show that, among the 26 tested medicinal plants, Ludwigia octovalvis, Vitis thunbergii, Rubus parvifolius, Lindernia anagallis, and Zanthoxylum nitidum exhibited strong activities and their IC50 values for DPPH radicals were 4.6, 24, 27, 36, 50 g/mL, respectively. As for the su- peroxide anion scavenging activity (IC50, g/mL), the top five most significant activities were observed in plant extracts of Ludwigia octovalvis (26  g/mL), Vitis thunbergii (58  g/mL), Prunella vulgaris (113  g/mL), Saurauia oldhamii (124  g/mL), and Rubus parvifolius (151  g/mL). The IC50 values for DPPH and superoxide anion of catechin (positive control) were 2.5 and 7.2  g/mL, respectively. It was also observed in the present study that, at 1 mg/mL, Ludwigia octovalvis and Bombax malabaricum exhibited significant protection onψx174 supe r- coiled DNA against strand cleavage induced by UV irradiated H2O2 with a superior or compati- ble effect to that of catechin.

Simultaneous Determination of Resveratrol Derivatives in Vitis thunbergii Plant by High Performance Liquid Chromatography

The roots of Vitis thunbergii Sieb. Zucc. (Vt-R) are well-known bone-protective medicinal material and rich in active resveratrol derivatives, as revealed in our previous studies. The present study used five compounds, including four isolated ones, ampelopsin C, (+)-vitisin A, (-)-vitisin B, and (+)-e-viniferin, and one purchased resveratrol, as standards to establish an HPLC method in order to simultaneously determine these contents in the sample materials. The analyses method was validated and was performed by using a reverse-phase column (Cosmosil 5C18-AR-II) with absorbance detection at 280 nm. The results showed that ampelopsin C, (+)-vitisin A and (-)-vitisin B were the major three constituents in Vt-R and their contents were 3.57, 2.99, and 1.69 mg/g, respectively. Meanwhile, resveratrol gave a level of 0.33 mg/g, which was much lower than those three major constituents. To determined the contents of five standards in the stems and leaves of this plant, except for (+)-e-viniferin, the levels of ampelopsin C, (+)-vitisin A, (-)-vitisin B, and resveratrol were 1.13, 0.27, 0.57, and 0.14 mg/g, respectively, in the stems, which were much less than those in root part. However, five compounds were not detected in leaves. This analytic method was also employed to investigate the qualities of five piece-packed raw materials (Vt-1-Vt-5) of root of V. thunbergii collected from the herb market. The levels of ampelopsin C, (+)-vitisin A, and (-)-vitisin B were in the range of ND-0.35, ND-1.10, and ND-1.20 mg/g, respectively, which were markedly less than those in Vt-R. These five compounds in other six plants of Vitaceae were also investigated, including V. vinifera L., V. kelungensis Moriyama,Ampelopsis brevipedunculata (Maxim.) Traut., V. thunbergii var. taiwanianaLu, Cissus pteroclada Hayata, and C. repens Lam. As a result, the former three plants were found to contain all of five standards. Except for resveratrol, other four compounds were not detected in V. thunbergii var.taiwaniana and C. repens. None of five compounds was found in C. pteroclada.

Percutaneous absorption of resveratrol and its oligomers to relieve psoriasiform lesions: In silico, in vitro and in vivo evaluations.

Resveratrol was shown to exert anti-inflammatory effects in experimental models of psoriasis. Several natural oligomers of resveratrol have been extracted from plants. We investigated the antipsoriatic activity of topical administration of resveratrol oligomers and explored the effect of the number of resveratrol subunits on skin absorption to establish the structure-permeation relationship (SPR). Three oligomers, ε-viniferin (dimer), ampelopsin C (trimer) and vitisin A (tetramer), extracted from Vitis thunbergii root were compared to the resveratrol glycoside polydatin. Delivery to porcine skin was assessed in vitro using the Franz cell. Keratinocytes activated with imiquimod (IMQ) were utilized to evaluate cytokine/chemokine inhibition. Topical application of resveratrol and oligomers was characterized in vivo by assessing cutaneous absorption, skin physiology, proinflammatory mediator expression, and histopathology in IMQ-treated mice. Skin deposition decreased as the molecular size and lipophilicity of the permeants increased. Resveratrol exhibited highest absorption, followed by ε-viniferin. The monomers resveratrol and polydatin exhibited higher flux across skin than the larger oligomers. In silico modeling revealed the permeants that strongly interacted with stratum corneum (SC) lipids exhibited lower transport to viable skin and the receptor compartment. In vitro, resveratrol and its derivatives had comparable ability to inhibit IMQ-induced IL-1β, IL-6, and CXCL8 secretion in activated keratinocytes. In vivo, topically applied ε-viniferin accumulated at higher levels than resveratrol (0.067 versus 0.029nmol/mg) in psoriasis-like mouse skin with impaired barrier capacity. Topical ε-viniferin alleviated psoriasiform symptoms and reduced IL-23 secretion (by 58% vs. 37%) more effectively than resveratrol. ε-Viniferin has potential as an anti-inflammatory agent to prevent or treat psoriasis.

Ampelopsins A and C Induce Apoptosis and Metastasis through Downregulating AxL, TYRO3, and FYN Expressions in MDA-MB-231 Breast Cancer Cells.

Ampelopsins A and C are resveratrol oligostilbenes whose role in cancer development remains unknown. This study evaluated the antimetastatic and apoptosis-inducing properties of ampelopsins A and C in MDA-MB-231 cells. The IC50 values of ampelopsins A and C against MDA-MB-231 cells at 72 h were 38.75 ± 4.61 and 2.71 ± 0.21 μM, respectively. However, at 24 h, ampelopsins A and C decreased cell metastasis significantly. Among the 71 proteins present on the human phosphoreceptor tyrosin kinase array, ampelopsin C decreased the phosphorylated protein level of AXL, Dtk (TYRO3), EphA2, EphA6, Fyn, Hck, and SRMS. Additionally, antiproliferation effects of ampelopsin C were enhanced when combined with luteolin and chrysin compared to either two or a single agent in MDA-MB-231 cells. Overall, ampelopsins A and C extracted from Vitis thunbergii are both novel antimetastatic agents and potential therapeutic targets in patients with breast cancer.

Protective mechanisms of resveratrol derivatives against TNF-α-induced inflammatory responses in rat mesangial cells

IntroductionResveratrol has been reported to alleviate inflammatory responses and oxidative stress in mesangial cells and in several types of renal injury in animal models. Previously, the active resveratrol derivatives from the roots of Vitis thunbergii Sieb. & Zucc. (Vitaceae) were shown to have significant anti-platelet and anti-oxidative activities. However, the anti-inflammatory mechanisms of these resveratrol derivatives in rat mesangial cells (RMCs) have not been clarified fully. MethodsThe protective mechanisms of resveratrol derivatives involved in tumor necrosis factor-α (TNF-α)-induced inflammatory responses were assessed by Western blot analysis, real-time PCR, and RT–PCR. The involvement of various signaling molecules in these responses was investigated using selective pharmacological inhibitors. ResultsNontoxic concentrations of the resveratrol derivatives significantly attenuated cytosolic phospholipase A2 (cPLA2) and cyclooxygenase 2 (COX-2) expression in RMCs challenged by TNF-α. These resveratrol derivatives inhibited TNF-α-activated ERK1/2 and JNK1/2 without affecting p38 phosphorylation. Next, we demonstrated that TNF-α induced NF-κB activation, translocation, and promoter activity, which was inhibited by pretreatment with resveratrol derivatives in RMCs. ConclusionThe protective mechanisms of resveratrol derivatives against TNF-α-stimulated inflammatory responses via cPLA2/COX-2/PGE2 inhibition was caused by the attenuation of the JNK1/2, ERK1/2, and NF-κB signaling pathways in RMCs.

Ethyl acetate fraction from methanol extraction of Vitis thunbergii var. taiwaniana induced G0 /G1 phase arrest via inhibition of cyclins D and E and induction of apoptosis through caspase-dependent and -independent pathways in human prostate carcinoma DU145 cells.

Vitis thunbergii var. taiwaniana (VTT) is a wild grape native to Taiwan, belonging to the Vitaceae family and Vitis genus, and widely used as folk herbal medicine. It is traditionally used for the treatment of diarrhea, hypertension, neuroprotection, jaundice, and arthritis. We used the wild-collected VTT and sterilized them to establish the plant tissue culture, and then took the leaves for DNA sequencing to determine its original base. We use methanol to extract VTT in four different solvents: 1-butanol, n-hexane, ethyl acetate, and water. These four preliminary extracts were used to treat human prostate cancer DU145 cells in vitro. We use the flow cytometry to check the cell survival situation. Finally, we found the ethyl acetate layer roughing product (referred VTEA) in human prostate cancer apoptotic effects of cell line DU-145. In the present studies, we use the crude extract of VTT to examine whether or not it can induce apoptosis of DU145 cells in vitro. Viability assays for extracts of VTT treatment showed that it had dose-dependent effect on human prostate cancer DU145 cells. We also found that the extract of VTT induces time-dependent mitochondrial and intrinsic-dependent apoptosis pathways. The in vitro cytotoxic effects were investigated by cell cycle analysis and the determination of apoptotic DNA fragmentation in DU145 cells. The cell cycle analysis showed that extracts of VTT induced a significant increase in the number of cells in G0 /G1 phase. The extract of VTT induced chromatin changes and apoptosis of DU145 cells also were confirmed by DAPI and PI staining that were measured by fluorescence microscopy and flow cytometry, respectively. Finally, the expression of relevant proteins was analyzed by Western blot analysis. These results promoted us to further evaluate apoptosis associated proteins and elucidate the possible signal pathway in DU-145 cells after treated with the extract of VTT.

Association of Activation of Induced COX-2, iNOS and Cytokines with NF-kappa B Depression by Taiwan Wild Grape Ethanolic Extract in Mice.

Taiwan wild grape (Vitis thunbergii var. taiwaniana; VTT) is an important traditional herbal medicine used to treat muscle injuries and acute and chronic pain of the ligaments. Information on its bioactivity and the underlying mechanisms, which have not been elucidated thus far, is needed to demonstrate its value for pharmacological and clinical use. This study presents evidence to clarify the antinociceptive and anti-inflammatory activities of an ethanolic extract of VTT stem (VTTEtOH) and the possible molecular mechanisms involved in such biactivities. In the mice, VTTEtOH significantly reduced the acetic acid-induced writhing response (P < 0.01), formalin-induced licking time (P < 0.01), and edema paw volume at 4 and 5 h after λ-carrageenan injection. VTTEtOH obviously decreased the levels of tumor necrosis factor alpha (P < 0.01), interleukin (IL)-1β (P < 0.05), interleukin (IL)-6 (P < 0.001), nuclear factor-kappa B (P < 0.001), iNOS (P < 0.001), cyclooxygenase-2 (P < 0.001) and Nitric oxide (P < 0.001) in edema-paw tissue. The molecular mechanisms underlying these effects might involve significant inhibition of the activity of cyclooxygenase-2 through suppression of nuclear factor-kappa B and inducible nitric oxide synthase expression and reduction of the levels of various inflammatory mediators, including tumor necrosis factor alpha, interleukin (IL)-1β, IL-6, and nitric oxide. Our findings provided pharmacological and histopathological evidences that VTTEtOH alleviates inflammatory pain-related diseases.

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.

개머루와 까마귀머루의 유전적 유연관계 분석

포도과(Vitaceae) 포도속(Vitis) 식물들 19종의 intergenic spacer 1 및 intergenic spacer 2의 염기서열을 Genbank에서 수집하였다. 그러나 국내에서 흔하게 발견되는 포도과 포도속 식물인 까마귀머루(Vitis thunbergii var. sinuata)와 포도과 개머루속 식물인 개머루(Ampelopsis brevipedunculata var. heterophylla)의 염기서열은 Genbank에서 발견할 수 없었다. 따라서 개머루와 까마귀머루를 채집하고 genomic DNA를 분리하여서 18S rDNA, ITS1, 5.8S rDNA, ITS2 및 28S rDNA의 일부를 증폭하고, 그 염기서열을 분석하였다. 이렇게 얻어진 염기서열을 다른 포도속 식물들의 염기서열과 MUSCLE (Multiple sequence comparison by log-expectation) algorithm으로 서로 비교하여 neighbor-joining tree 및 pairwise distance (p-distance)를 계산해 보았다. 그 결과 국내 자생종인 개머루와 까마귀 머루는 서로 간에는 높은 상동성을 보이지만 외국의 포도속 식물들과는 유전적 상관관계가 상당히 멀다는 것을 발견할 수 있었다. 이것은 아마도 우리나라 자생종들의 경우에 오랜 시간 동안 외국의 포도속 식물들과 지리적으로 격리된 상태에서 독립적으로 진화한 결과가 아닌가 생각된다. 또한 개머루와 까마귀머루의 염기서열의 상동성이 높은 데에도 불구하고, 형태를 기준으로 하는 기존의 분류체계에 따라서 개머루는 개머루속으로 까마귀머루는 포도속으로 분류가 되고 있다. 형태를 기준으로 하는 기존의 분류체계와 염기서열을 기준으로 하는 유전적 분류체계간의 괴리를 본 연구에서 다시 한 번 확인할 수 있었다. DNA sequences of the intergenic spacer 1 and intergenic spacer 2 of the nineteen plants belonging Vitis genus were collected from the Genbank. DNA sequences of the same regions of Vitis thunbergii var. sinuata and Ampelopsis brevipedunculata var. heterophylla, both common plants in Korea, were not available in Genbank. Those two plants were collected, their genomic DNA encoding 18S rRNA, intergenic spacer 1, 5.8S rRNA, intergenic spacer 2 and part of 28S rRNA amplified and DNA sequence determined. DNA sequences of twenty-one plants including two Korean plants were aligned by the Multiple sequence comparison by log-expectation(MUSCLE) algorithm and the alignment was used to calculate neighbor-joining tree and pairwise distance. The results indicate DNA sequences of the two Korean plants are highly homologous with each other, but they are quite distantly related to the other Vitis plants. Distant relationship of the two Korean plants with the other Vitis plants might be due to independent evolution of those two plants in geographically isolated environment. Those two Korean plants are classified in different genera based on the morphology, one in Vitis genus and the other in Ampelopsis genus, providing another example of discrepancy between morphological and genetic classification.

Polyphenols isolated from leaves of Vitis thunbergii var. taiwaniana regulate APP related pathway.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. The major component of the plaques, amyloid-β (Aβ), is generated from amyloid-β precursor protein (APP) by β- and γ-secretase-mediated cleavages. Multiple lines of evidence demonstrate that overproduction/accumulation of Aβ in vulnerable brain regions is a primary cause of the pathogenesis of AD. Among the twelve polyphenols isolated from the leaf extracts of Vitis thunbergii var. taiwaniana (VTT), stenophyllol C, stenophyllol B, ampelopsin C, vitisin A, and davidiol A were shown to significantly reduce both Aβ40 and Aβ42 levels in N2a695 cells. Further studies revealed that ampelopsin C and vitisin A reduce Aβ production through inhibiting β-secretase activity, while the effects of the other active polyphenols on reducing Aβ generation are through different mechanisms. These results suggest that VTT extracts may be beneficial for AD prevention and treatment.

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.

Chemical constituents and cytotoxicity assay research in small polar substances from Vitis thunbergii var. taiwaniana

This article studied the chemical constituents from the aerial part of Vitis thunbergii var. taiwaniana. The 60% ethanol extract was eluted with 95% ethanol though HP-20 macroporous adsorption resin column. 12 compounds, including (1) betulinic acid, (2)2, 2, 2'-bis (4-hydroxyphenyl) propane bis (2, 3-epoxypropyl) ether, (3) eriodictyol, (4) trans-ε-viniferin, (5) (+)-cis-ε-viniferin, (6) kobophenol A, (7) ampelopsin A, (8) nepalensinol B, (9) cis-miyabenol C, (10) cis-vitisin B, (11) cis-gnetin H and (12) (+)-hopeaphenol, were separated by using normal phase silica gel, ODS, Sephdadex LH-20 column chromatographies and semi-preparative or preparative HPLC. Compounds 2, 5, 6, 8, 9, 10, 11 were separated from the genus Vitis for the first time and compounds 3, 7, 12 were separated from Vitis thunbergii var. taiwaniana for the first time. At a concentration of 50 μmol · L(-1), compound 6, 7 and 11 showed strong cytotoxicity against MCF-7 cell lines with the inhibition rate of 66.58%, 57.16%, 52.84%, respectively.

Anti-α-glucosidase and Anti-dipeptidyl Peptidase-IV Activities of Extracts and Purified Compounds from Vitis thunbergii var. taiwaniana.

Ethanol extracts (Et) from the stem (S) and leaf (L) of Vitis thunbergii var. taiwaniana (VTT) were used to investigate yeast α-glucosidase and porcine kidney dipeptidyl peptidase-IV (DPP-IV) inhibitory activities. Both VTT-Et showed complete α-glucosidase inhibition at 0.1 mg/mL; VTT-S-Et and VTT-L-Et showed 26 and 11% DPP-IV inhibition, respectively, at 0.5 mg/mL. The VTT-Et interventions (20 and 50 mg/kg) resulted in improvements in impaired glucose tolerance of diet-induced obese rats. (+)-Hopeaphenol, (+)-vitisin A, and (-)-vitisin B were isolated from the ethyl acetate fractions of S-Et and showed yeast α-glucosidase inhibition (IC50 = 18.30, 1.22, and 1.02 μM) and porcine kidney DPP-IV inhibition (IC50 = 401, 90.75, and 15.3 μM) compared to acarbose (6.39 mM) and sitagliptin (47.35 nM), respectively. Both (+)-vitisin A and (-)-vitisin B showed mixed noncompetitive inhibition against yeast α-glucosidase and porcine kidney DPP-IV, respectively. These results proposed that VTT extracts might through inhibitions against α-glucosidase and DPP-IV improve the impaired glucose tolerance in diet-induced obese rats.

Vitis thunbergii supplementation demonstrates an anti-obesity effect in developing obese mice

IntroductionVitis thunbergii (VTE), an indigenous wild grape of Taiwan, has been widely used as folk medicine in Taiwan. In this study, we investigated the anti-obesity effect and safety of VTE in high-fat diet-fed C57BL/6JNarl mice. Materials and methodsMale C57BL/6JNarl mice were randomly divided into three groups fed with diets for 7 weeks: a high-fat diet (control group), high-fat diet with 0.375% V. thunbergii extract (1× VTE group), and high-fat diet with 0.75% V. thunbergii extract (2× VTE group). Body weight and food intake were recorded. The resected epididymal fat, liver, and kidney were collected for further analysis. ResultsOur data suggested an anti-obesity effect of VTE in high-fat diet-fed C57BL/6JNarl mice, as evidenced by the decreased body weight gain, epididymal fat pads weight, adipocyte size, liver weight, and hepatic fat deposition. Moreover, VTE supplementation lowered the level of blood glucose and serum triglyceride. However, histological changes and parallel elevation of serum GOT and GPT level demonstrated a potential hepatotoxicity in 0.75% VTE-supplemented group. The augmented liver injury was accompanied by fibrotic change, possibly through activation of α-SMA-positive matrix-producing cells. ConclusionsThe findings suggest that VTE supplementation showed anti-obesity effect and preferentially ameliorated glucose and lipid dysregulation in C57BL/6JNarl mice fed with a high-fat diet. However, the long-term use of VTE should be cautioned because of a potential hepatotoxicity, especially at higher doses.

Supplementation of Vitis thunbergii root extract alleviated high-fat diet-induced obesity in C57BL/6J mice

Vitis thunbergii root, widely used as folk medicine in Taiwan, has been found to contain polyphenolic compounds and resveratrol derivatives, which have been implicated in the prevention and treatment of obesity. Thus, we hypothesized it might show beneficial effects against obesity. C57BL/6JNarl mice fed with a high fat diet for 14 weeks increased body weight and epididymal fat pad weight, and accompanied by fatty liver, hyperglycemia, hyperinsulinemia, insulin resistance, hyperleptinemia, hypercholesterolemia, hyper-LDL-cholesterol, and high level of serum GPT, GOT, creatinine, and BUN. Supplementation of VTE in the last 7 weeks remarkably decreased body weight and epididymal fat pad weight, implying a potential anti-obesity effect. Mechanistic study showed that VTE supplementation increased energy expenditure-related CPT1 mRNA expression and AMPK phosphorylation, and decreased lipogenesis-related SREBP-1 expression in liver. In conclusion, Vitis thunbergii roots could alleviate high fat diet-induced obesity and its related complications by enhancing hepatic fatty acid oxidation and inhibitng lipogenesis.

Anti-Inflammatory Effects of Vitis thunbergii var. taiwaniana on Knee Damage Associated with Arthritis

Vitis thunbergii Sieb. et Zucc. var. taiwaniana Lu (VT) is an indigenous plant in Taiwan that is traditionally used for promoting joint health. In this study, we used in vitro primary human chondrocytes (PHCs) and two in vivo animal models to evaluate the anti-inflammatory effects of VT on arthritis. Results showed that the water extract of the stems and roots from VT (VT-SR) was rich in flavones and phenols with 1.1 mg/g of resveratrol, 6.7 mg/g of hopeaphenol, and 5.1 mg/g of (+)-ɛ-viniferin. VT-SR significantly scavenged DPPH radicals and inhibited prostaglandin E2 (PGE2) production in lipopolysaccharide (LPS)-induced PHCs without exhibiting significant cytotoxicity. In in vivo models, the VT-SR (500 mg/kg) significantly decreased serum PGE2 and knee 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) levels in LPS-induced acute inflammatory arthritis in rabbits. In addition, dietary supplementation with VT-SR for 28 days significantly alleviated type II collagenase-induced rat osteoarthritis with improvements in weight bearing and range of motion tests. In conclusion, our results suggest that the VT-SR is a good candidate for developing dietary supplements to prevent joint deterioration and inhibit inflammation.