Down-regulatory mechanism of mammea E/BB from Mammea siamensis seed extract on Wilms' Tumor 1 expression in K562 cells.

BackgroundWilms' tumor 1 (WT1) is a biological marker for predicting leukemia progression. In this study, mammea E/BB, an active compound from Saraphi (Mammea siamensis) seed extract was examined for its effect on down-regulatory mechanism of WT1 gene expression, WT1 protein and mRNA stability, and cell proliferation in K562 cell line.MethodsM. siamensis seeds were obtained from the region of Chiang Mai (North of Thailand). Mammea E/BB was extracted from seeds of M. siamensis. WT1 protein expression and stability were evaluated by Western blot analysis. WT1 mRNA stability was assessed by qRT-PCR. WT1-DNA binding and WT1 promoter activity were assayed by ChIP assay and luciferase-reporter assay, respectively. Cell cycle arrest was studied by flow cytometry.ResultsTreatment with mammea E/BB led to down-regulation of WT1 expression. The suppression of WT1 expression did not involve protein and mRNA degradation. Rather, WT1 protein was down-regulated through disruption of transcriptional auto-regulation of the WT1 gene. Mammea E/BB inhibited WT1-DNA binding at the WT1 promoter and decreased luciferase activity. It also disrupted c-Fos/AP-1 binding to the WT1 promoter via ERK1/2 signaling pathway and induced S phase cell cycle arrest in K562 cells.ConclusionMammea E/BB had pleotropic effects on kinase signaling pathways, resulting in inhibition of leukemia cell proliferation

A Novel Drug Modulator Diarylheptanoid (trans-1,7-Diphenyl-5-hydroxy-1-heptene) from Curcuma comosa Rhizomes for P-glycoprotein Function and Apoptosis Induction in K652/ADR Leukemic Cells

Curcuma comosa has been used in traditional Thai medicine to treat menstrual cycle-related symptoms in women. This study aims to evaluate the diarylheptanoid drug modulator, trans-1,7-diphenyl-5-hydroxy-1-heptene (DHH), in drug-resistant K562/ADR human leukemic cells. This compound was studied due to its effects on cell cytotoxicity, multidrug resistance (MDR) phenotype, P-glycoprotein (P-gp) expression, and P-gp function. We show that DHH itself is cytotoxic towards K562/ADR cells. However, DHH did not impact P-gp expression. The impact of DHH on the MDR phenotype in the K562/ADR cells was determined by co-treatment of cells with doxorubicin (Dox) and DHH using an MTT assay. The results showed that the DHH changed the MDR phenotype in the K562/ADR cells by decreasing the IC50 of Dox from 51.6 to 18.2 µM. Treating the cells with a nontoxic dose of DHH increased their sensitivity to Dox in P-gp expressing drug-resistant cells. The kinetics of P-gp mediated efflux of pirarubicin (THP) was used to monitor the P-gp function. DHH was shown to suppress THP efflux and resulted in enhanced apoptosis in the K562/ADR cells. These results demonstrate that DHH is a novel drug modulator of P-gp function and induces drug accumulation in the Dox-resistant K562 leukemic cell line

Suppression of inflammation-induced lung cancer cells proliferation and metastasis by exiguaflavanone A and exiguaflavanone B from Sophora exigua root extract through NLRP3 inflammasome pathway inhibition

Objective: Non-small cell lung cancer (NSCLC) is recognized for its aggressive nature and propensity for high rates of metastasis. The NLRP3 inflammasome pathway plays a vital role in the progression of NSCLC. This study aimed to investigate the effects of S. exigua extract and its active compounds on NLRP3 regulation in NSCLC using an in vitro model.Methods:S. exigua was extracted using hexane, ethyl acetate and ethanol to obtain S. exigua hexane fraction (SE-Hex), S. exigua ethyl acetate fraction (SE-EA), and S. exigua ethanol fraction (SE-EtOH) respectively. The active compounds were identified using column chromatography and NMR analysis. A549 cells were primed with lipopolysaccharide (LPS) and adenosine triphosphate (ATP) for activated NLRP3 inflammasome. The anti-inflammatory properties were determined using ELISA assay. The anti-proliferation and anti-metastasis properties against LPS-ATP-induced A549 cells were determined by colony formation, cell cycle, wound healing, and trans-well migration and invasion assays. The inflammatory gene expressions and molecular mechanism were determined using RT-qPCR and Western blot analysis, respectively.Results: SE-EA exhibited the greatest anti-inflammation properties compared with other two fractions as evidenced by the significant inhibition of IL-1β, IL-18, and IL-6, cytokine productions from LPS-ATP-induced A549 cells in a dose-dependent manner (p < 0.05). The analysis of active compounds revealed exiguaflavanone A (EGF-A) and exiguaflavanone B (EGF-B) as the major compounds present in SE-EA. Then, SE-EA and its major compound were investigated for the anti-proliferation and anti-metastasis properties. It was found that SE-EA, EGF-A, and EGF-B could inhibit the proliferation of LPS-ATP-induced A549 cells through cell cycle arrest induction at the G0/G1 phase and reducing the expression of cell cycle regulator proteins. Furthermore, SE-EA and its major compounds dose-dependently suppressed migration and invasion of LPS-ATP-induced A549 cells. At the molecular level, SE-EA, EGF-A, and EGF-B significantly downregulated the mRNA expression of IL-1β, IL-18, IL-6, and NLRP3 in LPS-ATP-induced A549 cells. Regarding the mechanistic study, SE-EA, EGF-A, and EGF-B inhibited NLRP3 inflammasome activation through suppressing NLRP3, ASC, pro-caspase-1(p50 form), and cleaved-caspase-1(p20 form) expressions.Conclusion: Targeting NLRP3 inflammasome pathway holds promise as a therapeutic approach to counteract pro-tumorigenic inflammation and develop novel treatments for NSCLC

Antibacterial tetraoxygenated xanthones from the immature fruits of Garcinia cowa

A phytochemical investigation of the acetone extract from the immature fruits of Garcinia cowa led to the isolation of two novel tetraoxygenated xanthones, garcicowanones A (1) and B (2), together with eight known tetraoxygeanted xanthones. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their antibacterial activity against Bacillus cereus TISTR 688, Bacillus subtilis TISTR 008, Micrococcus luteus TISTR 884, Staphylococcus aureus TISTR 1466, Escherichia coli TISTR 780, Pseudomonas aeruginosa TISTR 781, Salmonella typhimurium TISTR 292 and Staphylococcus epidermidis ATCC 12228. α-Mangostin showed potent activity (MIC 0.25-1 μg/mL) against three Gram-positive strains and garcicowanone A and β-mangostin exhibited strong antibacterial activity against B. cereus with the same MIC values of 0.25 μg/mL

PHYTOCHEMICAL AND CYTOTOXIC INVESTIGATIONS OF THE HEARTWOOD OF CAESALPINIA SAPPAN LINN

  Objective: The purpose of this study was to identify the chemical constituents in the dichloromethane extract by gas chromatography–mass spectrometry (GC–MS) analysis and evaluate the cytotoxic effects on leukemia cells of isolated compounds from Caesalpinia sappan Linn.Methods: Dichloromethane extract obtained from the heartwood of C. sappan was investigated by GC–MS and column chromatography. Cytotoxic effects on leukemia cells of the isolated compounds were examined using MTT assay.Results: The GC–MS analysis of dichloromethane extract from C. sappan revealed the presence of 14 compounds. Linoleic acid and β-sitosterol were found to be the major compounds presenting in 14% and 13%, respectively. The separation of the dichloromethane extract led to the isolation of brazilin (1) as a major compound, together with lupeol (2), and a mixture of β-sitosterol (3), and stigmasterol (4). Their structures were elucidated based on spectroscopic methods. Brazilin (1) showed a cytotoxic effect on human acute myeloid leukemia cell (KG1) and human acute myeloid leukemia stem cell (KG1a) with inhibitory concentration at 50% growth (IC50) values of 13.30 ± 0.49 and 12.24 ± 1.08 μg/ml, respectively. Conclusion: Many groups of phytochemical compounds in the dichloromethane extract of C. sappan were detected by GC–MS analysis. Some of them have been reported to possess various biological activities. Moreover, brazilin (1) isolated compound from C. sappan shows cytotoxicity on leukemia cells, which could be a potential anticancer property

Down-regulatory mechanism of mammea E/BB from Mammea siamensis seed extract on Wilms' Tumor 1 expression in K562 cells.

BackgroundWilms' tumor 1 (WT1) is a biological marker for predicting leukemia progression. In this study, mammea E/BB, an active compound from Saraphi (Mammea siamensis) seed extract was examined for its effect on down-regulatory mechanism of WT1 gene expression, WT1 protein and mRNA stability, and cell proliferation in K562 cell line.MethodsM. siamensis seeds were obtained from the region of Chiang Mai (North of Thailand). Mammea E/BB was extracted from seeds of M. siamensis. WT1 protein expression and stability were evaluated by Western blot analysis. WT1 mRNA stability was assessed by qRT-PCR. WT1-DNA binding and WT1 promoter activity were assayed by ChIP assay and luciferase-reporter assay, respectively. Cell cycle arrest was studied by flow cytometry.ResultsTreatment with mammea E/BB led to down-regulation of WT1 expression. The suppression of WT1 expression did not involve protein and mRNA degradation. Rather, WT1 protein was down-regulated through disruption of transcriptional auto-regulation of the WT1 gene. Mammea E/BB inhibited WT1-DNA binding at the WT1 promoter and decreased luciferase activity. It also disrupted c-Fos/AP-1 binding to the WT1 promoter via ERK1/2 signaling pathway and induced S phase cell cycle arrest in K562 cells.ConclusionMammea E/BB had pleotropic effects on kinase signaling pathways, resulting in inhibition of leukemia cell proliferation

Inhibitory effect of mammea E/BB from <i>Mammea siamensis</i> seed extract on Wilms' tumour 1 protein expression in a K562 leukaemic cell line

<div><p><i>Mammea siamensis</i> is used in traditional Thai medicine. This study was designed to extract and isolate an active compound from the <i>M. siamensis</i> seeds and to investigate its activity on Wilms' tumour 1 (WT1) protein expression in K562 cells. WT1 is a transcription factor that stimulates cell proliferation. The ethanol saraphi seed (ESS) extract was fractionated using <i>n</i>-hexane, ethyl acetate, <i>n</i>-butanol and water to obtain <i>n</i>-hexane saraphi seed (HSS), ethyl acetate saraphi seed (EASS), <i>n</i>-butanol saraphi seed (BSS), and water saraphi seed (WSS) extracts, respectively. The ESS, HSS and EASS extracts had strong cytotoxic effects on K562 cells in the MTT assay. All three fractions decreased WT1 protein levels and decreased total cell numbers. The HSS extract decreased the WT1 protein levels in a time- and dose-dependent manner. HPLC and NMR analyses indicated that the active compound of HSS was mammea E/BB. <i>M. siamensis</i> seeds are thus identified as a promising source of bioactive compounds for potential inhibition of WT1 protein expression.</p></div

Hydrophenalene-Cr(CO)(3) complexes as anti-inflammatory agents based on specific inhibition of NOD2 signalling: a SAR study

Small molecules, which specifically inhibit NOD2 signalling, are of high interest in the search for new anti-inflammatory drugs. In this context, the previously discovered hydrophenalene-Cr(CO)(3) complex 1 was taken as a lead and new structural analogues were prepared by means of chemical synthesis. The NOD2-inhibiting activity of the compounds was determined with cell-based reporter assays employing human embryonic kidney cells. As a result of the study, some clear structure activity relationships (SARs) could be identified. The best compounds were active at low mu M concentration

Reference gene selection for mRNA quantification in Haemonchus contortus

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Michaela Růžičková Supervisor: Ing. Petra Matoušková, Ph.D. Title of diploma thesis: Reference gene selection for mRNA quantification in Haemonchus contortus Haemonchus contortus is a parasitic nematode, whose multiresistance to ant- helmintics means global problem, threatening mostly small ruminants farming. Genom and transcriptom have been published in 2013, allowing gene expression studies to be conducted. Reference genes for this studies have not been validated yet. Use of suitable reference genes is essential for accurate normalization of gene expression levels. Aim of this work was to identify and validate potential reference genes for gene expression studies in H. contortus adults. Eleven genes were chosen, stability of their expression was assessed in males and females of two H. contortus strains, one drug-susceptible (ISE) and one multi-drug-resistant (WR). Total RNA was extracted and reverse trancribed to cDNA. cDNA was diluted and analyzed using quantitative real-time PCR with SYBR Green I detection. Expression stability was evaluated by computer programs BestKeeper, geNorm, NormFinder and the comparative CT method. Ncbp, ama, sodc, gapdh and farb were found to be most stable..