• 제목/요약/키워드: $K^+-Dependent$ phosphatase

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Characteristics of the Inhibitory Action of Protease Inhibitors on the Glucose-6-phosphate Transporter

  • Choi, Joon-Sig;Shin, Jeong-Sook;Choi, Hong-Sug;Park, Jong-Sang
    • BMB Reports
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    • 제30권2호
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    • pp.157-161
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    • 1997
  • The present paper reports characteristics and specificity of the inhibitory action of $N^{\alpha}-tosyl-L-lysine-chloromethyl\;ketone$ (TLCK) and $N^{\alpha}-tosyl-L-phenylalanine-chloromethyl\;ketone$ (TPCK) on the glucose6-phosphate transporter of rat liver microsomes. The TLCK-induced inhibition was pH dependent. The inhibition constants for TPCK were determined by following pseudo-Lst order reaction mechanism. The inhibition was protected by preincubation with excess amount of glucose-6-phosphate. The results proved that (a) TLCK inactivates the microsomal glucose-6-phosphate transporter, (b) the inhibition results from the modification of sulfhydryl groups of the transporter.

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MC3T3-E1 세포주에서 황기.계지.황백 처방(BHH10)의 골형성 촉진 효능 연구 (Effects of Astragalus Membranaceus, Innamomum Cassia, Phellodendron Amurensis(BHH10) on MC3T3-E1 Cells Proliferation, Differntiation and Bone Mineralized Formation)

  • 이미림;허정은;남동우;선종인;강중원;김성훈;최도영;이재동
    • Journal of Acupuncture Research
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    • 제29권6호
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    • pp.11-21
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    • 2012
  • Objectives : BHH10 is traditional medicine herb used for enhancing body resistance against various diseases. The aim of this study was to identify BHH10 extract induces osteogenic activity in human osteoblast-like MC3T3-E1 cells. Methods : MC3T3-E1, pre-osteoblast cell line, were treated with BHH10 of various concentrations($0.1{\mu}g/mL$, $1{\mu}g/mL$, $10{\mu}g/mL$). And then, the effect of BHH10 on osteoblast differentiation was examined by alkaline phosphatase(ALP) activity, von Kossa staining and RT-PCR for osteoblast differentiation markers such as osteocalcin(OCN), osteopontin(OPN). Results : BHH10 had dose-dependent effect on the viability of osteoblastic cells, and dose-dependently increased alkaline phosphatase(ALP) activity. BHH10 markedly increased mRNA expression for OCN, OPN in MC3T3-E1 cells. Also, BHH10 significantly induced mineralization in the culture of MC3T3-E1 cells. Conclusions : In conclusion, these results propose that BHH10 can play an important role in osteoblastic bone formation, osteogenesis, and may possibly lead to the development of bone-forming drugs.

법랑기질유도체가 탈회 치근표면에서 치주인대섬유아세포의 생물학적 성상에 미치는 영향 (Effects of enamel matrix derivatives on biologic activities of human periodontal fibloblasts to demineralized root surface)

  • 이강운;김태일;설양조;이용무;구영;류인철;정종평;한수부
    • Journal of Periodontal and Implant Science
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    • 제38권4호
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    • pp.679-690
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    • 2008
  • Purpose: The aim of this study was to investigate the effects of EMD on demineralized root surface using human periodontal ligament cells and compare the effects of root conditioning materials(tetracycline(TCN), EDTA). Material and Methods: Dentin slices were prepared from the extracted teeth and demineralized with TCN and EDTA. Demineralized dentin slices were incubated at culture plate with 25, 50 and $100{\mu}g/ml$ concentration of EMD. Cell attachment, alkaline phosphatase activity test, protein synthesis assay and scanning electronic microscopic examination were done. Results: Cells were attached significantly higher in EMD treated group at 7 and 14 days. Cell numbers were significantly higher in EMD treated group. Alkaline phosphatase activity was significantly higher in EMD treated group at 7 and 14 days. Protein synthesis was significantly higher in EMD treated group at 7 and 14 days. Conclusion: Enamel matrix derivatives enhance the biologic activities of human periodontal ligament cells on demineralized root surface and its effects are dependent on the concentration of EMD.

Ceramide is Involved in $MPP^+-induced$ Cytotoxicity in Human Neuroblastoma Cells

  • Nam, Eun-Joo;Lee, Hye-Sook;Lee, Young-Jae;Joo, Wan-Seok;Maeng, Sung-Ho;Im, Hye-In;Park, Chan-Woong;Kim, Yong-Sik
    • The Korean Journal of Physiology and Pharmacology
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    • 제6권6호
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    • pp.281-286
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    • 2002
  • To understand the cytotoxic mechanism of $MPP^+,$ we examined the involvement of ceramide in $MPP^+-induced$ cytotoxicity to human neuroblastoma SH-SY5Y cells. When SH-SY5Y cells were exposed to $MPP^+,\;MPP^+$ induced dose-dependent cytotoxicity accompanied by 2-fold elevation of intracellular ceramide levels in SH-SY5Y cells. Three methods were used to test the hypothesis that the elevated intracellular ceramide is related to $MPP^+-induced$ cytotoxicity: $C_2-ceramide$ was directly applied to cells, sphingomyelinase (SMase) was exogenously added, and oleoylethanolamine (OE) was used to inhibit degradation of ceramide. Furthermore, inhibition of ceramide-activated protein phosphatase (CAPP), the effector of ceramide, using okadaic acid (OA) attenuated cell death but treatment of fumonisin $B_1,$ the ceramide synthase inhibitor, did not alter the cytotoxic effect of $MPP^+.$ Based on these, we suggest that the elevation of intracellular ceramide is one of the important mediators in $MPP^+-induced$ cell death.

Endothelium Independent Effect of Pelargonidin on Vasoconstriction in Rat Aorta

  • Min, Young Sil;Yoon, Hyuk-Jun;Je, Hyun Dong;Lee, Jong Hyuk;Yoo, Seong Su;Shim, Hyun Sub;Lee, Hak Yeong;La, Hyen-Oh;Sohn, Uy Dong
    • Biomolecules & Therapeutics
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    • 제26권4호
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    • pp.374-379
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    • 2018
  • In this study, we investigated the effects of pelargonidin, an anthocyanidin found in many fruits and vegetables, on endothelium-independent vascular contractility to determine the underlying mechanism of relaxation. Isometric contractions of denuded aortic muscles from male rats were recorded, and the data were combined with those obtained in western blot analysis. Pelargonidin significantly inhibited fluoride-, thromboxane A2-, and phorbol ester-induced vascular contractions, regardless of the presence or absence of endothelium, suggesting a direct effect of the compound on vascular smooth muscles via a different pathway. Pelargonidin significantly inhibited the fluoride-dependent increase in the level of myosin phosphatase target subunit 1 (MYPT1) phosphorylation at Thr-855 and the phorbol 12,13-dibutyrate-dependent increase in the level of extracellular signal-regulated kinase (ERK) 1/2 phosphorylation at Thr202/Tyr204, suggesting the inhibition of Rho-kinase and mitogen-activated protein kinase kinase (MEK) activities and subsequent phosphorylation of MYPT1 and ERK1/2. These results suggest that the relaxation effect of pelargonidin on agonist-dependent vascular contractions includes inhibition of Rho-kinase and MEK activities, independent of the endothelial function.

Hepatoprotective Effect and Antioxidant Role of Caesalpinia bonducella on Paracetamol-induced Hepatic Damage in Rats

  • Gupta, Malaya;Mazumder, Upal Kanti;Kumar, Ramanathan Sambath
    • Natural Product Sciences
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    • 제9권3호
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    • pp.186-191
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    • 2003
  • The hepatoprotective effect of methanol extract of leaves of Caesalpinia bonducella was studied by means of paracetamol induced liver damage in rats. The degree of protection was measured by using biochemical parameters such as serum transaminase (SGPT and SGOT), alkaline phosphatase (ALP), bilirubin, and total protein. Further, the effects of the extract on lipid peroxidation (LPO), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) were estimated. The methanol extract of C. bonducella (MECB) (50,100 and 200 mg/kg) produced significant (P<0.01) hepatoprotective effect by decreasing the activity of serum enzymes, bilirubin, and lipid peroxidation, while it significantly increased increased the levels of GSH, SOD, CAT, and protein in a dose dependent manner. The effects of MECB were comparable to that of standard drug Silymarin. However, at a lower dose (25 mg/kg) it could not restore the deleterious effect produced by paracetamol. The results indicate that Caesalpinia bonducella had antioxidant and hepatoprotective effects.

Regulation of the Hepatic Antioxidative System by Astaxanthin in the Rats

  • Kang, Ji-One;Kim, Sung-Jin;Kim, Harriet
    • Preventive Nutrition and Food Science
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    • 제4권4호
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    • pp.251-254
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    • 1999
  • Astaxanthin is one of many carotenoids present in marine animals, vegetables and fruits. Since carotenoids are known to exert antioxidant actions, we explored to determine if astaxnathin could have such regulatory actions in normal-and $CCl_4$-treated rat liver. Astaxanthin treatment caused a slight increase in $\alpha$-tocopherol levels in the control rat liver. Glucose-6-phosphatase activity was significantly increased by astaxanthin in a dose-dependent manner and its activity decreased in response to $CCl_4$treatment was slightly inhibited by astaxanthin. These results suggest that astaxanthin could protect liver damages induced by $CCl_4$via inhibiting lipid peroxidation and it may have a potential to activate the anti-oxidant system of normal liver by stimulating $\alpha$-tocopherol production.

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일측성 신장 무형성을 동반한 제 1형 비타민 D 의존성 구룻병 1례 (A Case of Type I Vitamin D-dependent Rickets with Unilateral Aplasia of Kidney)

  • 임동희;정지인;임형은;은백린;유기환;홍영숙;이주원
    • Childhood Kidney Diseases
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    • 제12권1호
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    • pp.111-115
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    • 2008
  • 저자들은 특별한 가족력이 없으면서 저칼슘혈증, 저인산혈증, 경련, 혈청 알칼리성 인산분해효소의 증가, 1,25-$(OH)_2$ 비타민 D3 농도의 감소, 혈청 부갑상선 호르몬 농도의 증가 및 방사선 소견상 전형적인 구룻병 병소의 소견을 보인 제 1형 비타민 의존성 구룻병 환아에서 일측성 신장 무형성증이 동반되어 있었던 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다.

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참두릅 잎의 Protein Tyrosine Phosphatase 1B와 α-Glucosidase 저해 활성 (Inhibitory Activity of Aralia elata Leaves on Protein Tyrosine Phosphatase 1B and α-Glucosidase)

  • 조윤숙;성수희;바크타 히만수 쿠마르;정희진;문경호;최재수
    • 생약학회지
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    • 제47권1호
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    • pp.29-37
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    • 2016
  • Anti-diabetic potential of the leaves of A. elata through the inhibitory activity on PTP1B and ${\alpha}$-glucosidase has not been reported. In this study, the EtOAc fraction of methanolic extract from the leaves of A. elata showed potent inhibitory activity against the PTP1B and ${\alpha}$-glucosidase with $IC_{50}$ value of $96.29{\pm}0.3$ and $264.71{\pm}14.87{\mu}g/mL$, respectively. Three known triterpenoids, oleanolic acid, oleanolic acid-28-O-${\beta}$-D-glucopyranoside and oleanolic acid-3-O-${\beta}$-D-glucopyranoside were isolated from the most active EtOAc fraction. We determined the chemical structure of these triterpenoids through comparisons of published nuclear magnetic resonance (NMR) spectroscopic data. Furthermore, we screened these triterpenoids for their ability to inhibit PTP1B and ${\alpha}$-glucosidase over a range of concentrations ($12.5-50{\mu}M$). All three terpenoids significantly inhibited PTP1B in a concentration dependent manner and oleanolic acid effectively inhibited ${\alpha}$-glucosidase. In addition, these compounds revealed potent inhibitory activity with negative binding energies toward PTP1B, showing high affinity and tight binding capacity in the molecular docking studies. Therefore, the results of the present study clearly demonstrate that A. elata leaves and its triterpenoid constituents might be beneficial in the prevention or treatment of diabetic disease.

Isopsoralen Induces Differentiation of Prechondrogenic ATDC5 Cells via Activation of MAP Kinases and BMP-2 Signaling Pathways

  • Li, Liang;Eun, Jae-Soon;Nepal, Manoj;Ryu, Jae-Ha;Cho, Hyoung-Kwon;Choi, Bo-Yun;Soh, Yun-Jo
    • Biomolecules & Therapeutics
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    • 제20권3호
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    • pp.299-305
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    • 2012
  • Endochondral bone formation is the process by which mesenchymal cells condense to become chondrocytes, which ultimately form new bone. The process of chondrogenic differentiation and hypertrophy is critical for bone formation and as such is regulated by many factors. In this study, we aimed to indentify novel factors that regulate chondrogenesis. We investigated the possible role of isopsoralen in induction of chondrogenic differentiation in clonal mouse chondrogenic ATDC5 cells. Isopsoralen treatment stimulated the accumulation of cartilage nodules in a dose-dependent manner. Further, ATDC5 cells treated with isopsoralen were stained more intensely with Alcian blue than control cells, suggesting that isopsoralen increases the synthesis of matrix proteoglycans. Similarly, isopsoralen markedly induced the activation of alkaline phosphatase activity compared with control cells. Isopsoralen enhanced the expressions of chondrogenic marker genes such as collagen II, collagen X, OCN, Smad4 and Sox9 in a time-dependent manner. Furthermore, isopsoralen induced the activation of extracellular signal-regulated kinase (ERK) and p38 MAP kinase, but not that of c-jun N-terminal kinase (JNK). Isopsoralen significantly enhanced the protein expression of BMP-2 in a time-dependent manner. PD98059 and SB 203580, inhibitors of ERK and p38 MAPK, respectively, decreased the number of stained cells treated with isopsoralen. Taken together, these results suggest that isopsoralen mediates a chondromodulating effect by BMP-2 or MAPK signaling pathways, and is therefore a possible therapeutic agent for bone growth disorders.