• Title/Summary/Keyword: $LTB_4$

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Comparative study of the biological activities effect of Mentha arvensis L. extracts from water and 80% ethanol (열수 및 80% 에탄올로 추출한 박하의 생리활성 비교연구)

  • Choi, Dong-Hun;Seung, O-Tak;Lim, Mi-Hye
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.1
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    • pp.208-216
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    • 2019
  • The purpose of this study was to investigated the biological activities such as cytotoxic, anti-oxidant and anti-inflammatory using Mentha arvensis L. extracts. Mentha arvensis L. was prepared by extracting with DW and 80% ethanol, after cell viability was assessed by MTT assay using RAW 264.7 cells. Antioxidant activities, and Anti-inflammatory activities measured through changes in the levels of reactive oxygen species (ROS), nitric oxide (NO), leukotrien B4 (LTB4), and anti- or in-flammatory cytokines($IL-1{\beta}$, IL-6, tumor necrosis factor $(TNF)-{\alpha}$, and IL-10) on LPS-induced RAW 264.7 cells. All test measured by ELISA reader and Luminex. Mentha arvensis L. was no cytotoxic in water and 80% ethanol extracts, and Concentration of 100 ug/ml of 80% ethanol extract was suppressed the productions of ROS in LPS-induced RAW 264.7 cells. Also, Productions of NO, LTB4, inflammatory or anti-inflammatory cytokines showed efficacy change that dose-independent of all extracts. In other words, Mentha arvensis L. showed significant biological activities showing anti-inflammatory, and anti-oxidant. These results may be developed as a raw material for new health food and therapeutics to ease the symptoms mentioned above.

Molecular Dissection of the Interaction between hBLT2 and the G Protein Alpha Subunits

  • Vukoti, Krishna Moorthy;Lee, Won-Kyu;Kim, Ho-Jun;Kim, Ick-Young;Yang, Eun-Gyeong;Lee, Cheol-Ju;Yu, Yeon-Gyu
    • Bulletin of the Korean Chemical Society
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    • v.28 no.6
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    • pp.1005-1009
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    • 2007
  • Leukotriene B4 (LTB4) is a potent chemoattractant for leukocytes and considered to be an inflammatory mediator. Human BLT2 (hBLT2) is a low-affinity G-protein coupled receptor for LTB4 and mediates pertussis toxin-sensitive chemotactic cell movement. Here, we dissected the interaction between hBLT2 and G-protein alpha subunits using GST fusion proteins containing intracellular regions of hBLT2 and various Gα protein including Gα i1, Gα i2, Gα i3, Gα s1, Gα o1, and Gα z. Among the tested Gα subunits, Gα i3 showed the highest binding to the third intracellular loop region of hBLT2 with a dissociation constant (KD) of 5.0 × 10?6 M. These results suggest that Gα i3 has the highest affinity to hBLT2, and the third intracellular loop region of hBLT2 is the major component for the interaction with Gα i3.

Analytical Solutions for the Inelastic Lateral-Torsional Buckling of I-Beams Under Pure Bending via Plate-Beam Theory

  • Zhang, Wenfu;Gardner, Leroy;Wadee, M. Ahmer;Zhang, Minghao
    • International journal of steel structures
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    • v.18 no.4
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    • pp.1440-1463
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    • 2018
  • The Wagner coefficient is a key parameter used to describe the inelastic lateral-torsional buckling (LTB) behaviour of the I-beam, since even for a doubly-symmetric I-section with residual stress, it becomes a monosymmetric I-section due to the characteristics of the non-symmetrical distribution of plastic regions. However, so far no theoretical derivation on the energy equation and Wagner's coefficient have been presented due to the limitation of Vlasov's buckling theory. In order to simplify the nonlinear analysis and calculation, this paper presents a simplified mechanical model and an analytical solution for doubly-symmetric I-beams under pure bending, in which residual stresses and yielding are taken into account. According to the plate-beam theory proposed by the lead author, the energy equation for the inelastic LTB of an I-beam is derived in detail, using only the Euler-Bernoulli beam model and the Kirchhoff-plate model. In this derivation, the concept of the instantaneous shear centre is used and its position can be determined naturally by the condition that the coefficient of the cross-term in the strain energy should be zero; formulae for both the critical moment and the corresponding critical beam length are proposed based upon the analytical buckling equation. An analytical formula of the Wagner coefficient is obtained and the validity of Wagner hypothesis is reconfirmed. Finally, the accuracy of the analytical solution is verified by a FEM solution based upon a bi-modulus model of I-beams. It is found that the critical moments given by the analytical solution almost is identical to those given by Trahair's formulae, and hence the analytical solution can be used as a benchmark to verify the results obtained by other numerical algorithms for inelastic LTB behaviour.

Comparative Study of the Biological Activity Effects of Manjakani (Quercus infectoria Olivier) Extract using Water and 80% Ethanol (열수 및 80% 에탄올로 추출한 만자카니(Quercus infectoria Olivier)의 생리활성 비교연구)

  • Lee, Hea-Jin;Kim, Dong-Han;Lee, Eun-Jin;Lim, Mi-Hye
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.1
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    • pp.124-132
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    • 2020
  • The purpose of this study was to investigate the biological activities such as cytotoxicity and anti-inflammation using Manjakani (Quercus infectoria Olivier) extract. Manjakani was extracted from hot DW and 80% ethanol. Cell viability was assessed using MTT assay on RAW 264.7 cells. Also, anti-inflammatory activities were measured through changes in the levels of nitric oxide (NO), prostaglandin E2 (PGE2), leukotrien B4 (LTB4), pro-inflammatory cytokines (IL-1β, IL-6 and tumor necrosis factor (TNF)-α) and transcription factor on LPS-induced RAW264.7 cells. The results confirmed that significant cytotoxicity does not appear in the concentration range of 1, 5, and 10 ㎍/㎖ of both extracts of this study. The production of NO was slowed by approximately MDE 37.2% and MEE 43.7% at 10 ㎍/㎖ concentration. Also, level of PGE2 and LTB4 was decreased MDE 30.9%/MEE 43.7% and MDE 37.1%/MEE 43.7%. In the case of inflammatory cytokine was reduced to MDE 38.8%/MEE 50.8% for IL-1β, MDE 35.0%/MEE 44.2% for IL-6 and MDE 31.9%/MEE 36.6% for TNF-α at 10 ㎍/㎖ concentration. The mRNA expression of NF-κB, iNOS and COX-2 significantly decreased by MDE 44.0%/MEE 16.0%, MDE 44.0%/MEE 55.0% and MDE 45.0%/MEE 40.0%, respectively, following the 10 ㎍/mL sample treatment when compared to the control. Both extracts were effective in anti-inflammatory activity. In addition, both extracts showed efficient changes of production of NO, PGE2, LTB4, pro-inflammatory cytokines and transcription factor. But MEE was found to have a higher inhibitory effect than MDE. In other words, Manjakani was showed significant biological activities showing anti-inflammation without cytotoxicity. These results will be provided as fundamental data for further development of the new health food and therapeutics related to the results above.

The In Vitro and In Vivo Effect of Lipoxygenase Pathway Inhibitors Nordihydroguaiaretic Acid and Its Derivative Tetra-O-methyl Nordihydroguaiaretic Acid against Brucella abortus 544

  • Reyes, Alisha Wehdnesday Bernardo;Kim, Heejin;Huy, Tran Xuan Ngoc;Nguyen, Trang Thi;Min, Wongi;Lee, Dongho;Hur, Jin;Lee, John Hwa;Kim, Suk
    • Journal of Microbiology and Biotechnology
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    • v.32 no.9
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    • pp.1126-1133
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    • 2022
  • This study investigated the contribution of lipoxygenase (LOX) inhibitors, nordihydroguaiaretic acid (NDGA), tetra-O-methyl nordihydroguaiaretic acid (M4N) and zileuton (ZIL), and thromboxane A2 (TXA2) inhibitor 4,5-diphenylimidazole (DPI) in the proliferation of Brucella abortus infection. None of the compounds affected the uptake of Brucella into the macrophages. We determined the effect of neutralizing leukotriene B4 (LTB4) receptor and showed that the uptake of the bacteria was inhibited at 30 min post-infection. M4N treatment attenuated intracellular survival of Brucella at 2 h post-incubation but it was not observed in the succeeding time points. DPI treatment showed reduced survival of Brucella at 24 h post-incubation while blocking LTB4 receptor was observed to have a lower intracellular growth at 48 h post-incubation suggesting different action of the inhibitors in the course of the survival of Brucella within the cells. Reduced proliferation of the bacteria in the spleens of mice was observed in animals treated with ZIL or DPI. Increased serum cytokine level of TNF-α and MCP-1 was observed in mice treated with M4N or ZIL while a lower IFN-γ level in ZIL-treated mice and a higher IL-12 serum level in DPI-treated mice were observed at 7 d post-infection. At 14 d post-infection, ZIL-treated mice displayed reduced serum level of IL-12 and IL-10. Overall, inhibition of 5-LOX or TXA2 or a combination therapy promises a potential alternative therapy against B. abortus infection. Furthermore, strong ligands for LTB4 receptor could also be a good candidate for the control of Brucella infection.

Transepithelial Migration of Neutrophils in Response to Leukotriene $B_4$ is Mediated by a Reactive Oxygen Species-ERK-linked Cascade

  • Woo, Chang-Hoon;Kim, Jae-Hong
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.103-106
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    • 2003
  • The epithelial cells that form a barrier lining the lung airway are key regulators of neutrophil trafficking into the airway lumen in a variety of lung inflammatory diseases. Although the lipid mediator leukotriene B$_4$ (LTB$_4$) is known to be a principal chemoattractant for recruiting neutrophils to inflamed sites across the airway epithelium, the precise signaling mechanism involved remains largely unknown. (omitted)

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Effect of Conjugated Linoleic Acid on the Proliferation of the Human Colon Cancer Cell Line, HT-29 (Conjugated Linoleic Acid가 대장암 세포인 HT-29의 증식에 미치는 영향)

  • 김은지;조한진;김석종;강영희;하영래;윤정한
    • Journal of Nutrition and Health
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    • v.34 no.8
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    • pp.896-904
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    • 2001
  • Conjugated linoleic acid(CLA) is a group of positional and geometric isomers of linoleic acid(LA) and exhibits anticarcinogenic activity in multiple experimental animal models. Cis-9,trns-11(c9t11) and trans-10,cis-12(t10c12) CLA are the principal isomers found in foods. The present study was performed to determine whether CLA and the two isomers inhibits HT-29 cell proliferation and to assess whether such an effect was related to changes in secretion of eicosanoids. Cells were incubated in serum-free medium with various concentrations(0 to 20$\mu$M) of CLA or LA. CLA inhibited cell proliferation in a dose-dependent manner, with maximal inhibition(70 $\pm$ 1%) observed at 20$\mu$M concentration after 96 hours. However, LA had no effect at the same concentration range. To compare the ability of c9f11 and t10c12 to inhibit cell proliferation, cells were incubated with increasing concentrations(0 to 4$\mu$M) of these isomers. T10c12 inhibited cell proliferation in a dose-dependent manner. A 66 $\pm$ 2% decrease in cell number was observed within 96 hours after addition of 4$\mu$M t10c12. By contrast, c9t11 had no effect. The concentrations of CLA and the two isomers in the plasma membrane were increased when they were added to the incubation medium. However, they did not alter the levels of arachidonic acid in plasma membrane. To assess whether the proliferation inhibiting effect of CLA was related to changes in eicosanoid production, prostaglandin E$_2$(PGE$_2$) and leukotriene B$_4$(LTB$_4$) concentrations in conditioned media were estimated by a competitive enzyme immunoassay. Both CLA and t10c12 increased the production of materials reactive to PGE$_2$ and LTB$_4$ antibodies in a dose-dependent manner. By contrast, c9t11 had no effect. These results indicate that inhibition of HT-29 cell proliferation by CLA is attributed to the effect of the t10v12 isomer. The materials reactive to PGE$_2$ and LTB$_4$ antibodies may inhibit growth stimulatory effect of arachidonic acid-derived eicosanoids on HT-29 cell proliferation.

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Effect of DA-6034, a New Flavonoid Derivative, on TNBS-Induced Colitis in the Rats (새로운 플라보노이드 유도체인 DA-6034의 TNBS 유발성 염증성대장염 모델에서의 치료효과)

  • Son, Mi-Won;Ko, Jun-Il;Kim, Hee-Kee;Jang, Dong-Kyung;Yoo, Moo-Hi;Kim, Won-Bae;Lee, Kang-Chun;Song, In-Sung
    • YAKHAK HOEJI
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    • v.42 no.2
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    • pp.205-213
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    • 1998
  • The efficacy of DA-6034, a new flavonoid derivative, was investigated in comparison with sulfasalazine in a trinitrobenzene sulfonic acid (TNBS)-induced rat colitis. Under light anaesthesia with ether, rats were subjected to intracolonic administration of 30mg TNBS in 50% ethanol (0.5ml) and were then sacrificed at 7 or 21 days after colitis induction. The TNBS control group (the saline treated colitic rat) exhibited ulceration and inflammation of the distal colon with formation of granuloma and pathologic connections. Moreover, an increase in colonic myeloperoxidase (MPO) activity (investigated as an index of leukocyte adhesion and accumulation) and an elevated colonic leukotriene $B_4$ ($LTB_4$) level were observed. The colitic rats received DA6034 (0.3-30mg/kg) or sulfasalazine (50-100mg/kg), prednisolone (0.3-3mg/kg) after the induction of colitis until they were sacrificed. Oral treatment with DA-6034 resulted in significant reductions of macroscopic colonic damage, colonic inflammation. DA6034 had a more potent effect than sulfasalazine and prednisolone on macroscopic colonic damage, while it has similar effect with prednisolone on the reduction of colonic $LTB_4$ synthesis and MPO activity. This study show, therefore, that DA-6034 is effective m attenuating the colonic lesion in an TNBS-induced colitis model. Furthermore, the results suggest that the effect of DA-6034 is partially related to its action on $LTB_4$ synthesis and MPO inhibition.

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Long-term Bias of Internal Markers in Sheep and Goat Digestion Trials

  • De Carvalho, Gleidson Giordano Pinto;Garcia, Rasmo;Vieira Pires, Aureliano Jose;Silva, Roberio Rodrigues;Detmann, Edenio;Oliveira, Ronaldo Lopes;Ribeiro, Leandro Sampaio Oliveira
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.1
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    • pp.65-71
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    • 2013
  • Two digestion trials, one with sheep and another with goats, were conducted to evaluate the long-term bias (LTB) of the indigestible dry matter (iDM), indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) internal markers. The study used eight Santa In$\hat{e}$s castrated male sheep (average body weight of 16.6 kg) distributed in two $4{\times}4$ Latin squares and eight Saanen castrated male goats (average body weight of 22.6 kg) distributed in two $4{\times}4$ Latin squares. The experiments were conducted simultaneously, and the animals were housed in 1.2 $m^2$ individual pens with wood-battened floors equipped with individual feeders and drinkers. The animals received isonitrogenous diets that were offered ad libitum and contained 14% crude protein and 70% sugar cane (with 0, 0.75, 1.5 or 2.25% CaO, in natural matter percentage), corrected with 1% urea and 30% concentrate. The experiment consisted of four experimental periods of 14 d each, with the feed, leftovers and feces sampled on the last four days of each period. The marker concentrations in the feed, leftovers and fecal samples were estimated by an in situ ruminal incubation procedure with a duration 240 h. The relationship between the intake and excretion of the markers was obtained by adjusting a simple linear regression model, independently from the treatment (diets) fixed effects and Latin squares. For both the sheep and goats, a complete recovery of the iDM and iNDF markers was observed (p>0.05), indicating the absence of LTB for these markers. However, the iADF was not completely recovered, exhibiting an LTB of -9.12% (p<0.05) in the sheep evaluation and -3.02% (p<0.05) in the goat evaluation.