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Electrophoretic mobility shift assay (EMSA) technology has been widely employed for the analysis of transcription factors such as Forkhead box protein M1 (FOXM1). However, the application of high-throughput screening (HTS) in performing, such analyses are limited as it uses time consuming electrophoresis procedure and radioisotopes. In this study, we developed a FOXM1-DNA binding domain (DBD) binding assay based on time-resolved fluorescence energy transfer (TR-FRET) that enables HTS for the inhibitors of FOXM1-DNA interaction. This assay was robust, highly reproducible and could be easily miniaturized into 384-well plate format. The signal-to-background (S/B) ratio and Z' factor were calculated as 7.46 and 0.74, respectively, via a series of optimization of the assay conditions. A pilot library screening of 1019 natural compounds was performed using the FOXM1-DBD binding assay. Five hit compounds, namely, AC1LXM, BRN5, gangaleoidin, leoidin, and roemerine were identified as the inhibitors of FOXM1. In a cell viability assay, it was demonstrated that cell proliferation of FOXM1 overexpressed cell lines was suppressed in cell lines such as MDA-MB-231 and MCF-7 by five hit compounds. These results indicate that developed FOXM1-DBD binding assay can be applied to highly efficiency HTS of compound libraries.

The popular screening method for urotensin (UT) receptor antagonists is to measure the intracellular calcium concentration with a calcium-sensitive fluorescent dye. This assay format has an inherent limitation on the problem related to the fluorescence interference as it involves fluorescent dyes. In the present study, a label-free assay for the screening of UT receptor antagonists was developed by using dynamic mass redistribution (DMR) assay based on label-free optical biosensor. The addition of urotensin II (UII) stimulated a DMR profile to HEK293 cells stably expressing the human UT receptor (HEK293UT cells) but not on parental cells. The EC50 value of UII in label-free assay was 4.58 nM, which is very similar to that in conventional calcium mobilization assay (4.15 nM). Compared with the calcium mobilization assay for UII (Z′ factor, 0.77), the current label-free assay presented improved Z′ factor (0.81), with a relatively similar S/B ratio (28.0 and 25.6, respectively). The known high-affinity UT receptor antagonists, SB657510, GSK562590, and urantide, exhibited comparable IC50 values but rather less potent in the DMR assay than in calcium mobilization. Our DMR assay was able to present various functional responses, including inverse agonism in SB657510 and GSK1562590 as well as partial agonism in urantide. Moreover, the DMR assay exerted the stable antagonist window upon the minimal agonist stimulus. These results suggest that the label-free cell-based UT receptor assay can be applicable to evaluate the various functional activities of UT receptor-related drug candidates.

PURPOSE: The purpose of this study was to investigate the effects of 3 dimensional exercises and Klapp’s exercise on parameters of scoliosis in subjects with non-structure scoliosis. METHOD: This study was performed on 24 subjects. Twenty-four subjects were divided into two groups; 3 dimensional exercise(n=12), Klapp’s exercise(n=12). Both of the group performed the exercise 3 times a week for 5 weeks. The data was analyzed by the Paired t-test for comparing before and after changes of factors in each group and the Independent t-test for comparing the between groups. RESULT: The result are as follows. There was statistically significant difference of before and after arthopometric parameters, trunk flexion, Cobb's angle in 3 dimensional exercise(p 0.05). CONCLUSION: As a result of this study, we found that the 3 dimensional exercise may be effective more than Klapp’s exercise.

Polymyxin B is widely used antibiotic in the clinic for resistant Gram-negative infections. In addition, polymyxin B-immobilized hemoperfusion cartridge has been used for endotoxin removal therapy in patients with septic shock. The aim of this study was to investigate the anti-fibrotic and anti-cellular hypertrophic effects of polymyxin B, and further to explore its possible mechanism. Polymyxin B (3, 10 μM) significantly inhibited stress fiber formation induced by angiotensin II (Ang II) in rat heart-derived H9c2 cells. Furthermore, polymyxin B (1 - 10 μM) showed a potent inhibitory effect on Ang II-induced cellular hypertrophy in H9c2 cells. Under the mechanism study, the inhibitory activities of polymyxin B against kinases involved in cellular hypertrophy such as AKT1, CAMK, GRK5, GSK3β, MLCK, PKC, PKD2, AMPK, ROCK2, p70S6K, SGK1were evaluated. Polymyxin B possesses a potent G protein related kinase 5 (GKR5) inhibitory activity with IC50 value of 1.1 μM, and has an ATP non-competitive inhibitory mode. Taken together, these results indicate that polymyxin B alleviates Ang II-induced stress fiber formation and cellular hypertrophy, and propose that one mechanism underlying these effects involves inhibition of the GRK5 pathway.

Recent advances in basic and clinical studies have identified Rho kinase (ROCK) as an important target potentially implicated in a variety of cardiovascular diseases and ROCK inhibitors were considered as a pharmacological strategy to prevent and treat cardiovascular diseases. To screen the small molecule compound library against ROCK, a high throughput screening (HTS) campaign was carried out using immobilized metal affinity for phosphochemicals (IMAP)-based time-resolved fluorescence resonance energy transfer (TR-FRET) assay. Z' value and signal to background (S/B) ratio were achieved at 0.76 and 5.27 for the pilot library screening of the most diverse set consisting of 15,040 compounds with a reasonable reconfirmation rate. From this screening campaign, four novel scaffolds, such as 3- nitropyridine, 4-methoxy-1,3,5,-triazine, naphthalene-1,4-dione, and 2,3-dihydro-1H-pyrrolo[2,3-b]quinoxaline, were yielded. Particularly, we found that 3-nitropyridine derivatives possess potent inhibitory activity and selectivity for ROCK. Our findings provide important information for the design of novel ROCK inhibitor.

Salvianolic acid A, an active compound present in Salvia miltiorrhiza, is a phenolic carboxylic acid derivative, ((2R)-3-(3,4-Dihydroxyphenyl)-2-[(E)-3-[2-[(E)-2-(3,4-dihydroxyphenyl) ethenyl]-3,4-dihydroxyphenyl] prop-2-enoyl]oxypropanoic acid). The present study was performed to investigate the underlying mechanisms of anti-inflammatory effects with salvianolic acid A, specially focused on nuclear factor κB (NF-κB) signaling pathway by targeting the IκB kinase β (IKKβ). The effect of salvianolic acid A for IKKβ activity was analyzed using an immobilized metal affinity for phosphochemicals (IMAP)-based time-resolved fluorescence resonance energy transfer (TR-FRET) assay. The underlying mechanisms of salvianolic acid A were examined using lipopolysaccharide (LPS)-stimulated RAW264.7 cells. IKKβ studies based on IMAP-TR-FRET showed that salvianolic acid A possesses a potent IKKβ inhibitory activity with Ki value of 3.63 μM in an ATP-noncompetitive manner. Pretreatment with salvianolic acid A (10, 30 μM) decreased LPS-induced expression of iNOS and COX-2, thereby inhibiting production of nitric oxide and prostaglandin E(2), respectively. In addition, salvianolic acid A (10, 30 μM) also attenuated the LPS-induced IκBα phosphorylation and degradation, and NF-κB translocation. These results suggest that salvianolic acid A modulates NF-κB-dependent inflammatory pathways through IKKβ inhibition and these anti-inflammatory effects will aid in understanding the pharmacology and mode of action of salvianolic acid A.

Aim of the study The present study was performed to investigate the underlying mechanisms of anti-inflammatory effects with the extract of Euonymus alatus (EEA), and specially focused on nuclear factor κB (NF-κB) signaling pathway by targeting the IκB kinase β (IKKβ). Materials and methods The effect of EEA for IKKβ activity was analyzed using an immobilized metal affinity for phosphochemicals (IMAP)-based time-resolved fluorescence resonance energy transfer (TR-FRET) assay. The effect of EEA on lipopolysaccharide (LPS)-induced NF-κB activation in murine macrophage RAW 264.7 cells with western blotting and immunofluorescent staining was evaluated. Results IKKβ studies based on IMAP-TR-FRET showed that EEA possesses a potent IKKβ inhibitory activity with IC 50 value of 11.83 μg/ml. EEA (10, 30 μg/ml) also attenuated the LPS-induced IκBα phosphorylation/degradation, NF-κB translocation and subsequent NO synthesis in RAW 264.7 cells. Conclusions These results suggest that EEA abrogates LPS-induced NF-κB signaling pathway by targeting the IKKβ in RAW 264.7 cells and these properties may provide a molecular basis for understanding the inhibitory effects of EEA on LPS-mediated inflammation.

Acute alcohol ingestion is well known to have deleterious effects on memory and also known to inhibit long-term potentiation, a putative cellular substrate of memory. In this study, we for the first time revealed that growth-associated protein 43 (GAP-43), which is well known as a presynaptic substrate of protein kinase C and one of the major synaptic plasticity-related genes, was down regulated by single ethanol administration (2.5 g/kg, 15% in saline, i.p.) in the rat hippocampus. Using real-time PCR, we confirmed that GAP-43 mRNA level is significantly decreased 2 h after ethanol administration. GAP-43 and p-GAP-43 (Ser41) immunoreactivities in the hippocampus were also reduced 4 h after ethanol administration. Immunohistochemical study showed that the reduction of GAP-43 and p-GAP-43 expression was associated with the perforant and mossy fibers pathways. These results suggest that the reduction of GAP-43 in the hippocampus might be, at least in part, a cause of memory impairment after acute ethanol ingestion.

Kamolonol (7-[[(1R,2R,4R,4aS,5R,8aS)-4-hydroxy-1,2,4a,5-tetramethyl-6-oxo-3,4,5,7,8,8a-hexahydro-2H-naphthalen-1-yl]methoxy]chromen-2-one) is a sesquiterpene coumarin and an active component of gum extracts from Ferula assafoetida. The aim of this study was to investigate the anti-fibrotic and anti-cellular hypertrophic effects of kamolonol, and further to explore its possible mechanism. Kamolonol (3–30 μM) significantly inhibited stress fiber formation induced by angiotensin II (Ang II) in rat heart-derived H9c2 cells. Furthermore, kamolonol (3–30 μM) showed a potent inhibitory effect on Ang II-induced cellular hypertrophy in H9c2 cells. Next, a Rho-associated kinase (ROCK) activity was measured because actin stress fiber formation and/or cellular hypertrophy are usually induced by the activation of ROCK. Rho-associated kinase 2 (ROCK2) studies using a time-resolved fluorescence resonance energy transfer (TR-FRET) showed that kamolonol possesses a potent ROCK2 inhibitory activity with IC50 values of 2.27 μM, and has an ATP-competitive inhibitory mode. In validation study, pretreatment of kamolonol (3–30 μM) for 2 h decreased the Ang II-induced phosphorylation of myosin phosphatase 1 (MYPT1) and myosin light chain 2 (MLC2). Taken together, these results indicate that kamolonol suppresses Ang II-induced stress fiber formation and cellular hypertrophy, and propose that one mechanism underlying these anti-fibrotic and anti-cellular hypertrophic effects involves inhibition of the ROCK-MLC pathway.

Baicalein is a flavonoid (5,6,7-trihydroxy-2-phenyl-4H-1-benzopyran4-one) and an active principle in Scutellaria baicalensis. The present study was performed to investigate the mechanisms underlying the anti-fibrotic effects of baicalein with a focus on Rho kinase (ROCK) inhibition. The effect of baicalein on ROCK activity was analyzed using an immobilized metal affinity for phosphochemicals (IMAP)-based time-resolved fluorescence resonance energy transfer (TR-FRET) assay. The underlying mechanisms of baicalein were examined using angiotensin II-stimulated H9c2 cells. Rho kinase (ROCK1 and ROCK2) studies using IMAP-TR-FRET showed that baicalein possesses potent ROCK inhibitory activity with IC50 values of 6.55 and 2.82 µM, respectively. Pretreatment with baicalein (for 2 h) concentration-dependently decreased the angiotensin II-induced phosphorylation of myosin phosphatase (MYPT) and myosin light chain (MLC). Furthermore, baicalein also concentration-dependently suppressed actin stress fiber formation in angiotensin II-stimulated H9c2 cells. These results suggest that baicalein potently inhibits ROCK and that by so doing it modulates actin stress fiber formation. These anti-fibrotic effects of baicalein explain, at least in part, its pharmacology and mode of action.

It has been known that ethanol causes neuronal cell death through oxidative stress. Ethanol itself and reactive oxygen species (ROS) produced by ethanol modulate intracellular signaling pathways including mitogen-activated protein kinase (MAPK) cascades. This study was conducted to examine the impact of ethanol on MAPK signaling in HT22 cells. Ethanol (100 and 400 mM) caused activation of ERK, p38 MAPK, and JNK. ERK activation occurred in early time and p38 MAPK activation was evident when ERK activation was diminished. Specific inhibitor of p38 MAPK (SB203580) protected HT22 cells against ethanol, which was accompanied by an inhibition of ROS accumulation. However, inhibitors of ERK (U0126) and JNK (SP600125) had no effects on ethanol-induced neuronal cell death when they are treated with ethanol for 24 h. These results suggest that p38 MAPK may have important roles in ROS accumulation during ethanol-induced oxidative stress in HT22 cells.

Ethanol has deleterious effects on neuronal cells both in vivo and in vitro, but the mechanisms are unknown. Here, treatment with increasing doses of ethanol (from 20 up to 600mM) decreased the viability of a mouse hippocampal neuroblastoma cell line, HT22. The glutathione concentration decreased and intracellular reactive oxygen species (ROS) increased in a dose-and time-dependent manner, suggesting that the neurotoxicity was due to oxidative stress. Expression of heme oxygenase (HO)-1, a redox regulator and heat shock protein, increased with time after ethanol treatment, but HO-2 was expressed constitutively. The addition of 5microM zinc protoporphyrin IX (ZnPP IX), a competitive HO inhibitor, with the ethanol further reduced cell viability and increased intracellular ROS, but these effects were reversed by co-treatment with 50nM bilirubin, a well-known antioxidant and a product of HO catalysis. These results suggest that HO has a protective role in hippocampal neurons as an intrinsic factor against ethanol-induced oxidative stress and the protection depends on the degree of oxidative stress.