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Orapin Insuan Phornphimon Janchai Benchaluk Thongchuai Rujirek Chaiwongsa Supaporn Khamchun Somphot Saoin Wimonrut Insuan Peraphan Pothacharoen Waraporn Apiwatanapiwat Antika Boondaeng Pilanee Vaithanomsat 《Current issues in molecular biology》2021,43(1):93
Bromelain is a mixture of proteolytic enzymes derived from pineapple (Ananas comosus) fruit and stem possessing several beneficial properties, particularly anti-inflammatory activity. However, the molecular mechanisms underlying the anti-inflammatory effects of bromelain are unclear. This study investigated the anti-inflammatory effects and inhibitory molecular mechanisms of crude and purified rhizome bromelains on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells. RAW264.7 cells were pre-treated with various concentrations of crude bromelain (CB) or purified bromelain (PB), and then treated with LPS. The production levels of pro-inflammatory cytokines and mediators, including nitric oxide (NO), interleukin (IL)-6, and tumor necrosis factor (TNF)-α were determined by Griess and ELISA assays. The expressions of inducible nitric oxide synthetase (iNOS), cyclooxygenase (COX)-2, nuclear factor kappa B (NF-κB), and mitogen-activated protein kinases (MAPKs)-signaling pathway-related proteins were examined by western blot analysis. The pre-treatment of bromelain dose-dependently reduced LPS-induced pro-inflammatory cytokines and mediators, which correlated with downregulation of iNOS and COX-2 expressions. The inhibitory potency of PB was stronger than that of CB. PB also suppressed phosphorylated NF-κB (p65), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha, extracellular signal-regulated kinases, c-Jun amino-terminal kinases, and p38 proteins in LPS-treated cells. PB then exhibited potent anti-inflammatory effects on LPS-induced inflammatory responses in RAW264.7 cells by inhibiting the NF-κB and MAPKs-signaling pathways. 相似文献
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Maitarad P Saparpakorn P Hannongbua S Kamchonwongpaisan S Tarnchompoo B Yuthavong Y 《Journal of enzyme inhibition and medicinal chemistry》2009,24(2):471-479
Comparative molecular field analysis (CoMFA) was performed on twenty-three pyrimethamine (pyr) derivatives active against quadruple mutant type (Asn51Ile, Cys59Arg, Ser108Asn, Ile164Leu) dihydrofolate reductase of Plasmodium falcipaarum (PfDHFR). The represented CoMFA models were evaluated based on the various three different probe atoms, C(sp3) (+1), O(sp3) (-1) and H (+1), resulting in the best model with combined three types of probe atoms. The statistical results were r(2)(cv) = 0.702, S(press) = 0.608, r(2)(nv) = 0.980, s = 0.156, and r(2)(test-set) = 0.698 which can explain steric contribution of about 50%. In addition, an understanding of particular interaction energy between inhibitor and surrounding residues in the binding pocket was performed by using MP2/6-31G(d,p) quantum chemical calculations. The obtained results clearly demonstrate that Asn108 is the cause of pyr resistance with the highest repulsive interaction energy. Therefore, CoMFA and particular interaction energy analyses can be useful for identifying the structural features of potent pyr derivatives active against quadruple mutant type PfDHFR. 相似文献
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Phornphimon Maitarad Jin Han Liyi Shi Chirawat Chitpakdee Jittima Meeprasert 《Molecular simulation》2017,43(13-16):1240-1246
AbstractHerein, we demonstrate that the degrees of catalytic performance of M-CeO2-based catalysts (M=Mn, Cu, Ru or Zr) for an ammonia selective catalytic reduction (NH3-SCR) of nitric-oxide (NO) can be estimated using three theoretical terms; (i) an oxygen vacancy formation energy of a catalyst, (ii) an adsorption energy of NO and (iii) an adsorption energy of NH3. Those terms predict the trend of the catalytic performance as the order; Mn–CeO2 > Cu–CeO2 > Ru–CeO2 > Zr–CeO2 > CeO2. To verify the theoretical prediction, the catalysts were synthesized and tested their performances on the NH3-SCR of NO reaction. The normalized NO conversion rates at low temperatures (100–200 °C) were measured for Mn–CeO2, Cu–CeO2, Ru–CeO2, Zr–CeO2 and CeO2 as 2.61–7.46, 1.30–6.82, 0.73–3.02, 0.81–3.31 and 1.55–2.33 mol s?1 m?2, respectively. In addition, a concept of a structure-activity relationship analysis shows a strong relationship between theoretical and experimental results. Consequently, an application of predicting the catalytic performance of catalysts from theoretical calculations prior the catalyst synthesis is useful in catalyst design and screening that can reduce time and cost. 相似文献
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Phornphimon Maitarad Patchreenart Saparpakorn Sumalee Kamchonwongpaisan Bongkoch Tarnchompoo Yongyuth Yuthavong 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):471-479
Comparative molecular field analysis (CoMFA) was performed on twenty-three pyrimethamine (pyr) derivatives active against quadruple mutant type (Asn51Ile, Cys59Arg, Ser108Asn, Ile164Leu) dihydrofolate reductase of Plasmodium falcipaarum (PfDHFR). The represented CoMFA models were evaluated based on the various three different probe atoms, Csp3 (+1), Osp3 ( ? 1) and H (+1), resulting in the best model with combined three types of probe atoms. The statistical results were = 0.702, Spress = 0.608, = 0.980, s = 0.156, and = 0.698 which can explain steric contribution of about 50%. In addition, an understanding of particular interaction energy between inhibitor and surrounding residues in the binding pocket was performed by using MP2/6-31G(d,p) quantum chemical calculations. The obtained results clearly demonstrate that Asn108 is the cause of pyr resistance with the highest repulsive interaction energy. Therefore, CoMFA and particular interaction energy analyses can be useful for identifying the structural features of potent pyr derivatives active against quadruple mutant type PfDHFR. 相似文献
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