• Bulletin of the Korean Chemical Society
• /
• 제34권8호
• /
• pp.2487-2490
• /
• 2013

SA51, a medium potency inhibitor of protein tyrosine phosphatase 1B (PTP1B), was identified to be a potent inhibitor of $I{\kappa}B$ kinase ${\beta}$ ($IKK{\beta}$). Consistent with this, SA51 prevented lipopolysaccharide (LPS)-induced breakdown of $I{\kappa}B{\alpha}$ in macrophages. The effects of SA51 in mice were compared with those of structurally related compounds, SA18 and SA32, which were previously reported as inhibitors of both enzymes - less potent against $IKK{\beta}$ but more potent against PTP1B compared to SA51. SA51 improved glucose tolerance and lipid parameters in mice, consistent with the results reported for $IKK{\beta}^{+/-}$ mice. In contrast, SA18 and SA32 showed anti-obesity effects without anti-diabetic effects. Collectively, the effects of SA51 could be due largely to the inhibition of $IKK{\beta}$, whereas SA18 and SA32 may be more likely to inhibit PTP1B, consistent with their relative in vitro inhibitory effects.

• 한국군사과학기술학회지
• /
• 제14권6호
• /
• pp.1018-1025
• /
• 2011

The improved properties of corrosion for 90Cu10NiFe alloy in natural seawater were explained by sodium diethyl dithio carbamate(NaDDC), namely organic compound, which is reagent for heavy metal extractions of waste water. The efficiency of NaDDC as corrosion inhibitor for 90Cu10NiFe alloy has been investigated in seawater after immersion in various concentrations of NaDDC solutions for 12~36hrs at pH 8.2 by weight loss test and electrochemical techniques including potentiodynamic polarization and SEM-EDS measurements. The results showed that the corrosion resistance of 90Cu10NiFe alloy improves with the increasing concentration of NaDDC but it did not improves with increasing time any more, so the highest inhibition efficiency was 93% at 100mg/L, 36hrs. The results obtained from weight losses and corrosion rates in polarization curve measurements were in good agreement. Therefore, it showed that NaDDC is a good inhibitor for copper corrosion of 90Cu10NiFe alloy.

• Clinical and Experimental Reproductive Medicine
• /
• 제34권4호
• /
• pp.239-252
• /
• 2007

목 적: 사람의 HAD와 HUC를 심근세포로 분화 유도하고자 하였다. 연구방법: 사람의 HAD와 HUC를 분리하여 5-azacytidine을 24시간 처리하고 여러 가지 BMP와 FGF을 첨가하여 배양하였다. 또한 HUC은 BMP와 FGF와 함께 activin A 또는 TGF-$\beta$1 또는 Wnt inhibitor를 첨가하여 배양한 후 심근세포 특이 유전자의 발현을 조사하였다. 결 과: HAD를 5-azacytidine 처리하고 기본배양액에서 4주 동안 배양하였을 때 TnT 유전자가 새로이 발현하였으며 Cmlc1과 kv4.3의 발현 양이 증가하였다. 5-azacytidine 처리 후에 BMP-4와 함께 FGF-4 (B4/F4) 또는 FGF-8 (B4/F8)을 첨가하여 배양하였을 때는 $\beta$-MHC 유전자 발현이 새로이 유도되었으며, Cmlc1, TnT, TnI 그리고 Kv4.3 유전자 발현 양이 더 많이 증가하였다. HUC은 5-azacytidine 및 BMP와 FGF 처리에 의해 유전자 발현 변화가 없었다. 그러나 BMP와 FGF와 함께 activin A 또는 TGF-$\beta$1을 첨가하여 배양하였을 때, BMP-2와 FGF-8 (B2/F8)을 첨가하여 배양한 세포에서 $\beta$-MHC 발현이 새로이 유도되었으며 $\alpha$-CA, TnT 그리고 Kv4.3 유전자의 발현이 증가하였다. 또한 BMP와 FGF와 함께 Wnt inhibitor를 처리하여 1주 동안 배양하였을 때 Cinlc1 유전자 발현이 새로이 유도되었으며 $\alpah$-CA, TnT, TnI 그리고 Kv4.3의 발현이 증가되었다. 결 론: HAD는 BMP와 FGF 처리에 의해 심근세포 특이 유전자의 발현증가를 유도할 수 있었으며 HUC는 BMP와 FGF와 함께 activin A 또는 TGF-$\beta$1 또는 Wnt inhibitor를 처리함으로써 심근세포 특이 유전자의 발현증가를 유도할 수 있었다. 따라서 HAD와 HUC는 심장질환 치료를 목적으로 하는 세포 치료에 이용될 수 있을 것으로 사료된다.

• Applied Biological Chemistry
• /
• 제39권2호
• /
• pp.104-111
• /
• 1996

감자의 genomic DNA library로 부터 분리한 proteinase inhibitor II (pin2) 유전자들의 제한효소 지도를 작성 하였던바 이미 분리된 상처 유발 (wound-inducible)pin2K 유전자의 것과 상이성이 있는 pin2T를 분리하여 염기서열을 결정하였다. 두 유전자의 염기서열은 전체적으로 약 86%의 동일성을 보였으며 특히 promoter 부위의 염기서열은 pin2K 유전자의 전사개시 부위의 상대적인 위치인 -714까지 네부분의 결손(20 내지 60bp)을 제외하던 약 91%수준의동일성을 보였다. 분리한 유전자들의 promoter 부위를 표지 유전자인 CAT와 GUS 유전자에 연결 시킨후 담배에서의 발현을 추적하였던바, pin2K 유전자의 promoter에 의한 표지유전자의 발현은 상처에 의해 발현 되었으나 pin2T 유전자의 promoter에 의한 표지유전자의 발현은 상처 유무와 관계없이 낮은 수준으로 나타났다. 또한 pin2T 유전자의 Promoter 내의 결손은 핵 단백질의 promoter에의 결합에 영향을 주지 않았으며 상처 유발pin2K 유전자의 promoter 염기서열과 비교하였을때 pin2T 유전자의 promoter 부위내에 5'-AGTAAA-3'라는 특별한 염기부위가 자연적으로 제거된것을 알수 있었다. 또한 5'-AGTAAh-3'의 염기부위가 다른 상처 유발 유전자들에서는 흔히 발견되고, 다른 식물 유전자들의 Promoter에서는 쉽게 발견이 되지 않았다. 따라서 상처 유발 pin2K 유전자의 Promoter내에 상처 유발과 관련있는 특별한 염기부위가 자연적으로 결실되어 pin2T 유전자의 발현이 상처 유발성을 잃은것으로 짐작된다.

• Molecules and Cells
• /
• 제44권1호
• /
• pp.38-49
• /
• 2021

Airway mucus secretion is an essential innate immune response for host protection. However, overproduction and hypersecretion of mucus, mainly composed of the gel-forming MUC5AC protein, are significant risk factors for patients with asthma and chronic obstructive pulmonary disease (COPD). The transforming growth factor β (TGFβ) signaling pathway negatively regulates MUC5AC expression; however, the underlying molecular mechanism is not fully understood. Here, we showed that TGFβ significantly reduces the expression of MUC5AC mRNA and its protein in NCI-H292 cells, a human mucoepidermoid carcinoma cell line. This reduced MUC5AC expression was restored by a TGFβ receptor inhibitor (SB431542), but not by the inhibition of NF-κB (BAY11-7082 or Triptolide) or PI3K (LY294002) activities. TGFβ-activated Smad3 dose-dependently bound to MUC5AC promoter. Notably, TGFβ-activated Smad3 recruited HDAC2 and facilitated nuclear translocation of HDAC2, thereby inducing the deacetylation of NF-κB at K310, which is essential for a reduction in NF-κB transcriptional activity. Both TGFβ-induced nuclear translocation of Smad3/HDAC2 and deacetylation of NF-κB at K310 were suppressed by a Smad3 inhibitor (SIS3). These results suggest that the TGFβ-activated Smad3/HDAC2 complex is an essential negative regulator for MUC5AC expression and an epigenetic regulator for NF-κB acetylation. Therefore, these results collectively suggest that modulation of the TGFβ1/Smad3/HDAC2/NF-κB pathway axis can be a promising way to improve lung function as a treatment strategy for asthma and COPD.

• Natural Product Sciences
• /
• 제11권3호
• /
• pp.145-149
• /
• 2005

A methanol soluble extract from the dried hooks and stems of Uncaria rhynchophylla showed a strong inhibitory activity against monoamine oxidase in mouse brain. Using a bioassay-guided purification of this extract, a known ${\beta}-carboline$ type alkaloid, harman (1), was obtained as an active constituent. In addition, five known indole alkaloids, isocorynoxeine (2), isorhynchophylline (3), corynoxeine (4), cadambine (5), and $3{\alpha}-dihydrocadambine$ (6), were isolated and found to be weakly active or inactive.

• Natural Product Sciences
• /
• 제10권5호
• /
• pp.223-227
• /
• 2004

This study was carried out to investigate inhibitory effect of extracts from the root of Paeonia lactiflora on postprandial hyperglycemia. Organic solvent (hexane, ethyl acetate, butanol, aqueous) extracts from the crude drug were fractionated by high performance liquid chromatography. These fractions were examined to evaluate ${\alpha}-glucosidase$ (EC 3. 2. 1. 20) inhibition by microplate colorimetric assay. Among the fractions examined, the ethyl acetate fraction from the roots of Paeonia lactiflora showed potent inhibitory effects on ${\alpha}-glucosidase$. Therefore, further fractionation of the fraction was carried out to isolate the active principles. Finally, we isolated and Purified 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) as a active principle by activity-guided fractionation. These results suggest that the extract from the root of Paeonia lactiflora can be used as a new nutraceutial for inhibition on postprandial hyperglycemia and PGG might be a candidate for developing an ${\alpha}-glucosidase$ inhibitor.

• Journal of Microbiology and Biotechnology
• /
• 제10권5호
• /
• pp.606-611
• /
• 2000

Dimorphic yeast Candida albicans reversibly switches between the form of yeast and hyphae depending on external conditions. We investigated possible roles of the myosin family in the growth and dimorphic switches of C. albicans with a general myosin ATPase inhibitor, 2,3-butanedione-2-monoxime (BDM). Transition to hyphae as well as proliferation by budding was completely inhibited by BDM at 16 mM. Presence of 16 mM BDM did not affect hyphae-to-bud transition but it blocked budding. The effects of BDM on yeast growth and dimorphic switches were reversible. More than 70% of the BDM-treated cells demonstrated defects in the amount and the polarized localization of F-actin as well as in the shape and migration of the nucleus, suggesting that myosin activities are needed in these cellular processes of C. albicans.

• Natural Product Sciences
• /
• 제5권1호
• /
• pp.48-53
• /
• 1999

There are epidemiological evidences that the population with high fecal ${\beta}-glucuronidase$ activity has greater risk of colon cancer than the population with low fecal ${\beta}-glucuronidase$. This relationship was investigated by using the mouse-dimethylhydrazine colon carcinogenesis model and the extract of antler which was a ${\beta}-glucuronidase$ inhibitor. Mice with low fecal ${\beta}-glucuronidase$ activity induced by administration of water and Folch's fraction of antler had significantly fewer aberrant crypts after injections of 1,2-dimethylhydrazine (DMH) than mice treated with DMH alone. The result supports the hypothesis that the inhibitor of ${\beta}-glucuronidase$ such as antler extract can protect an animal against the induction of colon cancer.

• Natural Product Sciences
• /
• 제18권4호
• /
• pp.211-214
• /
• 2012

Since 15-hydroxyprostaglandin dehydrogenase (15-PGDH) is the key metabolic enzyme of prostaglandin $E_2$ ($PGE_2$), inhibition of 15-PGDH is supposed to facilitate various physiological functions by increasing $PGE_2$. Methanol extract of Artemisia argyi (AAME) inhibited 15-PGDH ($IC_{50}$: $13.13{\mu}g/mL$) with relatively low cytotoxicity ($IC_{50}$: $415.00{\mu}g/mL$) and elevated extracellular $PGE_2$ levels in HaCaT cells. Real-time PCR analysis showed that AAME decreased significantly mRNA expression of PG transporter (PGT) in HaCaT cells. These results indicate that AAME could be applicable to functional materials as a 15-PGDH inhibitor and PGT expression inhibitor for the upregulation of extracellular $PGE_2$ level.