• Journal of Ginseng Research
• /
• v.38 no.1
• /
• pp.28-33
• /
• 2014

Background: Panax notoginseng has been used as a general tonic agent to invigorate human body for millennia in China and continued to be used until present. Methods: Some chromatographic methods were performed to isolate pure triterpenoids, and their structures were determined by nuclear magnetic resonance (NMR) experiments. Anti-diabetes activities of isolated compounds were evaluated through their inhibitory activity of protein tyrosine phosphatase 1B (PTP1B) enzyme. Results and Conclusion: Three new dammarane-type triterpenoids, notoginsenoside-LX (1), notoginsenoside-LY (2), and notoginsenoside-FZ (3) together with eighteen known compounds were isolated from the Panax notoginseng leaves. The structure-activity relationship of the compounds with dammaranetype triterpenoids and their PTP1B inhibitory activity were also reported. Results showed that compounds 2, 15, 20, and 21 can significantly inhibit the enzyme activity of PTP1B in a dose-dependent manner, with inhibitory concentration 50 ($IC_{50}$) values of $29.08{\mu}M$, $21.27{\mu}M$, $28.12{\mu}M$, and $26.59{\mu}M$, respectively. The results suggested that Panax notoginseng leaves might have potential as a new therapeutic agent for the treatment of diabetes.

• Natural Product Sciences
• /
• v.13 no.4
• /
• pp.311-316
• /
• 2007

In this study, the twenty-four ethyl acetate extracts of twenty-two medicinal plants, traditionally used in Vietnam as anti-diabetes agents, were investigated for ${\alpha}$-amylase and protein tyrosine phosphatase 1B (PTP1B) enzymes inhibitory activity in vitro. The results indicated that, twelve materials (50.0%) showed moderate to strong inhibitory activity in ${\alpha}$-amylase inhibitory activity with $IC_{50}$ values ranging from 2.5 to $48.8{\mu}g/mL$; meanwhile, ten extracts (41.6%) could demonstrate PTP1B activity with $IC_{50}$ values less than $30.5{\mu}g/mL$. Some plants presented interesting activities against both of ${\alpha}$-amylase and PTP1B enzymes such as Catharanthus roseus, Carthamus tinctorius, Momordica charantia, Gynostemma pentaphyllum, Glycyrrhiza glabra, Smilax glabra, Psidium guajava (leave), and Rehmannia glutinosa. The study may provide a proof, at least in a part, for the ethno-medical use in diabetes disease of these plants.

• Bulletin of the Korean Chemical Society
• /
• v.24 no.10
• /
• pp.1455-1464
• /
• 2003

Several series of compounds (benzoic acids, pyrazolecarboxylic acids, phenoxyacetic acids, and quinolinoxyacetic acids) were prepared and evaluated for their inhibitory activity against PTP-1B. Several compounds showed submicromolar inhibitory activity.

• BMB Reports
• /
• v.46 no.11
• /
• pp.533-538
• /
• 2013

The expression of matrix metalloproteinases (MMPs) produced by cancer cells has been associated with the high potential of metastasis in several human carcinomas, including breast cancer. Several pieces of evidence demonstrate that protein tyrosine phosphatases (PTP) have functions that promote cell migration and metastasis in breast cancer. We analyzed whether PTP inhibitor might control breast cancer invasion through MMP expression. Herein, we investigate the effect of 4-hydroxy- 3,3-dimethyl-2H benzo[g]indole-2,5(3H)-dione (BVT948), a novel PTP inhibitor, on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion in MCF-7 cells. The expression of MMP-9 and cell invasion increased after TPA treatment, whereas TPA-induced MMP-9 expression and cell invasion were decreased by BVT948 pretreatment. Also, BVT948 suppressed NF-${\kappa}B$ activation in TPA-treated MCF-7 cells. However, BVT948 didn't block TPA-induced AP-1 activation in MCF-7 cells. Our results suggest that the PTP inhibitor blocks breast cancer invasion via suppression of the expression of MMP-9.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.11
• /
• pp.3359-3365
• /
• 2010

The incorporation of microwave irradiation with the prevalent "click chemistry" is currently of considerable synthetic interest. We describe here the introduction of such laboratorial shortcut into carbohydrate-based drug discovery, resulting in the rapid formation of a series of triazole-linked salicylic $\beta$-D-O-glycosides with biological activities. All "clicked" products were achieved in excellent yields ($\approx$ 90%) within only a quarter. In addition, based on the structural characteristics of the afforded glycomimetics, their inhibitory activities were evaluated toward protein tyrosine phosphatases 1B (PTP1B) and a panel of homologous protein tyrosine phosphatases (PTPs). Docking simulation was also conducted to plausibly propose binding modes of this glycosyl salicylate series with the enzymatic target.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.10
• /
• pp.2861-2862
• /
• 2013

• Bulletin of the Korean Chemical Society
• /
• v.25 no.9
• /
• pp.1303-1304
• /
• 2004

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.2
• /
• pp.175-181
• /
• 2013

This study investigated the ability of extracts from Lentinus edodes (LE) and rice with Lentinus edodes mycelium (LEM) to inhibit diabetes and obesity. Lipid accumulation significantly decreased by 78% and 74% upon treatment with 300 ${\mu}g/mL$ of LE and LEM, respectively (p<0.01). Cholesteryl ester transfer protein (CETP) inhibition activity increased by 94% and 99% upon treatment with 300 ${\mu}g/mL$ of LE and LEM, respectively. In order to investigate the effect of LE and LEM on diabetes, the inhibition of protein tyrosine phosphate 1B (PTP1B) activity from the LE and LEM extracts at various concentrations (1, 3, 10, 30, 100, 300 ${\mu}g/mL$) was assessed. PTP1B activity by treatment with 10, 30, and 100 ${\mu}g/mL$ of LE, was inhibited at a rate of 7, 9, and 7% respectively. Also, PTP1B activity from treatment with increasing concentration of LEM led to a significant concentration-dependent inhibition of PTP1B activity (p<0.01). LE and LEM were orally administered for 28 days after a high fat diet (HFD). LE and LEM significantly reduced triglyceride, cholesterol, HDL-cholesterol and LDL-cholesterol levels. GOT and GPT were not significantly effected. These results indicate that extracts of LE and rice with LEM have potent activities useful in the treatment of obesity and diabetes mellitus.

• Journal of the Korean Chemical Society
• /
• v.46 no.3
• /
• pp.296-300
• /
• 2002

• Proceedings of the PSK Conference
• /
• 2005.11a
• /
• pp.208-209
• /
• 2005