• Korean Journal of Pharmacognosy
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• v.44 no.2
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• pp.176-181
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• 2013

In order to search for protein tyrosine phosphatase 1B (PTP1B) inhibitors as therapy of type 2 diabetes and obesity from Korean traditional prescriptions, we selected 58 traditional prescriptions based on a review of the Korean traditional medicine books. The hot water extracts of Korean traditional prescriptions were screened for the inhibitory activity against PTP1B. Among the tested extracts, water extracts of Jakgamhwangsinbu-tang, Seonbanghwalmyung-eum, and Takreeonjoong-tang showed relatively good inhibitory activity against PTP1B at the concentration of $30{\mu}g/ml$. Additionally, we evaluated PTP1B inhibitory effect for each herbal ingredient and composition in Jakgamhwangsinbu-tang (芍甘黃辛附湯). Of the tested ingredients from this herbal medicine, water extracts of Paeoniae Radix rubra and Rhei Rhizoma, and ethanol extracts of Paeoniae Radix alba, Rhei Rhizoma, Asiasari Radix, and Aconiti Tuber showed good PTP1B inhibitory effect. Herbal compositions composed of these active herbal ingredients exhibited significant activity for PTP1B inhibition over 70% at $7.5{\mu}g/ml$.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.16-21
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• 2004

Protein tyrosine phosphatase 1B(PTP1B) is thought to be a negative regulator in insulin signal-transduction pathway. Insulin-resistance by the activation of PTP1B is a hallmark of both type 2 diabetes and obesity. Thus, the compounds inhibiting PTP1B can improve insulin resistance and can be effective in treating type 2 diabetes and obesity. The methanol extracts of 160 herbal medicines were screened for the inhibitory activity against PTP1B. Among the tested extracts, methanol extracts of Amsonia elliptica, Areca catechu, Benincasa hispida, Morus alba, Salvia miltiorrhiza, Siegesbeckia orientalis, and Trichosanthes kirilowii showed relatively strong inhibitory activity against PTP1B.

• Natural Product Sciences
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• v.14 no.2
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• pp.143-146
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• 2008

Protein tyrosine phosphatase 1B (PTP1B) is emerging as a potential therapeutic target for the treatment of type-2 diabetes and obesity. To search for new types of PTP1B inhibitors, we have undertaken in vitro enzyme assay for some anthraquinones and stilbenes isolated from plants. Of the anthraquinones tested, physcion (1), 1-O-methylemodin (2), and emodin (3) showed high activities, with $IC_{50}$ values of 7.6, 7.0, and $3.8{\mu}g/mL$, respectively, while the anthraquinone glycosides, physcion-8-O-${\beta}$-D-glucopyranoside (4) and emodin-8- O-${\beta}$-D-glucopyranoside (5), were less active than their aglycones. All the stilbenens (6 - 15) slightly inhibited PTP1B activity at high concentration of $30{\mu}g/mL$. Our findings suggest that the hypoglycemic effect of anthraquinones may be associated with their PTP1B inhibitory activity.

• Natural Product Sciences
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• v.16 no.4
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• pp.239-244
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• 2010

Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signaling, has served as a potential drug target for the treatment of type 2 diabetes. The MeOH extracts of twenty-nine medicinal plants, traditionally used in Vietnam as anti-diabetes agents, were investigated for PTP1B inhibitory activity in vitro. The results indicated that, most materials showed moderate to strong inhibitory activity with $IC_{50}$ values ranging from $3.4\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$; meanwhile, eleven extracts (37.9%) could demonstrate PTP1B activity with $IC_{50}$ values less than $15.5\;{\mu}g/mL$; sixteen extracts (55.2%) could demonstrate PTP1B activity with $IC_{50}$ values ranging from $15.5\;{\mu}g/mL$ to $35.1\;{\mu}g/mL$. The study may provide a proof, at least in a part, for the ethno-medical use in diabetes disease of these plants.

• ALGAE
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• v.19 no.3
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• pp.271-276
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• 2004

One hundred and fifty four micro algal strains, newly isolated from nationwide freshwaters in Korea, were screened for their anticancer, ant diabetic, and antibiotic activities. The micro algal strains were cultured with different nutritional conditions that were divided into 4 groups as follows; a normal Allen medium, nitrogen (N)-limited medium, phosphorus (P)-limited medium, and N and P-limited medium. Algal biomass was extracted with a mixture of acetone:H₂O (1:1, v:v) and the extracts were used for the screening of bioactive materials. Anticancer, ant diabetic, and antibiotic materials were screened by the methods of vaccinia Hl-related protein tyrosine phosphates (VHR DS-PTPase) inhibition, protein tyrosine phosphates 1B (PTP1B) inhibition, and paper disk. The inhibition activity of VHR DS-PTPase was observed in 18 strains, having a maximum 79% inhibition from Anabaena affinis and the inhibition activity of PTP1B was observed in 9 strains, having a maximum 97% from Sphaerocystis schroeteri. Microcystis aeruginosa incubated in an N and P-limited medium showed antibiotic activity in 8 species out of 13 pathogenic bacteria. As a whole, it seemed that the stressed condition such as N and/or P limitation increased the production of bioactive materials in micro algae.

• Bulletin of the Korean Chemical Society
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• v.26 no.7
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• pp.1138-1140
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• 2005

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.1029-1033
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• 2012

A number of evidence have been accumulated that the regulation of reversible tyrosine phosphorylation, which can be regulated by the combinatorial activity of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs), plays crucial roles in various biological processes including differentiation. There are a total of 107 PTP genes in the human genome, collectively referred to as the "PTPome." In this study, we performed PTP profiling analysis of the HIB-1B cell line, a brown preadipocyte cell line, during brown adipogenesis. Through RT-PCR and real-time PCR, several PTPs showing differential expression pattern during brown adipogenesis were identified. In the case of PTP-RE, it was shown to decrease significantly until 4 days after brown adipogenic differentiation, followed by a dramatic increase at 6 days. The overexpression of PTP-RE led to decreased brown adipogenic differentiation via reducing the tyrosine phosphorylation of the insulin receptor, indicating that PTP-RE functions as a negative regulator at the early stage of brown adipogenesis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1532-1536
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• 2008

Quercetin which isolated form the roots of Houttuynia cordata. was determined on the basis of IR, ID and 2D NMR specta by direct comparison with authentic compounds. Protein tyrosine phophatase 1B (PTP1B) is thought to be a negative regulator in insulin signal-transduction pathway. Insulin-resistance by the activation of PTP1B is a hallmark of both type 2 diabetes and obesity. Thus, the compound inhibiting PTP1B can improve insulin resistance and can be effective in treating type 2 diabetes and obesity. Quercetin which measured the inhibitory activity against PTP1B was 92.1% inhibition in the 30 ${\mu}g$/mL, 83.4% inhibition in the 6 ${\mu}g$/mL and 76.5% inhibition in the 3 ${\mu}g$/mL. These results suggest that quercetin retains a potential PTP1B activity.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.275-277
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• 2012

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1505-1508
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• 2012

Protein tyrosine phosphatase 1B (PTP1B) is a key factor in negative regulation of the insulin pathway, and is a promising target for the treatment of type-II diabetes, obesity and cancer. Herein, compound ($\mathbf{4}$) was first observed to have moderate inhibitory activity against PTP1B with an $IC_{50}$ value of $13.72{\pm}1.53{\mu}M$. To obtain more potent PTP1B inhibitors, we synthesized a series of chalcone derivatives using compound ($\mathbf{4}$) as the lead compound. Compound $\mathbf{4l}$ ($IC_{50}=3.12{\pm}0.18{\mu}M$) was 4.4-fold more potent than the lead compound $\mathbf{4}$ ($IC_{50}=13.72{\pm}1.53{\mu}M$), and more potent than the positive control, ursolic acid ($IC_{50}=3.40{\pm}0.21{\mu}M$). These results may help to provide suitable drug-like lead compounds for the design of inhibitors of PTP1B as well as other PTPs.