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1.
J Chromatogr Sci ; 61(10): 953-962, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36892162

RESUMO

This study was planned to develop a simple high-performance thin-layer chromatography method for qualitative and quantitative estimation of 3-acetyl-11-keto-ß-boswellic acid (AKBBA), ß-boswellic acid (BBA), 3-oxo-tirucallic acid (TCA) and serratol (SRT) with HPTLC-ESI-MS/MS for characterization in Boswellia serrata Roxb. oleo gum resin extract. The method was developed with hexane-ethyl acetate-toluene-chloroform-formic acid as mobile phase. RF values observed for AKBBA, BBA, TCA and SRT were 0.42, 0.39, 0.53 and 0.72, respectively. The method was validated according to International Council for Harmonisation guidelines. The concentration range for linearity was 100-500 ng/band for AKBBA and 200-700 ng/band for the other three markers with r2 > 0.99. The method resulted in good recoveries as 101.56, 100.68, 98.64 and 103.26%. The limit of detection was noticed as 25 , 37, 54 and 38 ng/band, with a limit of quantification as 76, 114, 116 and 115 ng/band, for AKBBA, BBA, TCA and SRT, respectively. The four markers were identified and confirmed in B. serrata extract using TLC-MS by indirect profiling by LC-ESI-MS/MS and were identified as terpenoids, TCA and cembranoids: AKBBA (mass/charge (m/z) = 513.00), BBA (m/z = 455.40), 3-oxo-tirucallic acid (m/z = 455.70) and SRT (m/z = 291.25), respectively.


Assuntos
Boswellia , Triterpenos , Espectrometria de Massas em Tandem , Boswellia/química , Extratos Vegetais/química , Triterpenos/química
2.
In Silico Pharmacol ; 10(1): 19, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36199809

RESUMO

The healing of wound is a tightly-regulated cascade of events, involving interplay of enormous factors. Now a days, pain alleviation and faster wound healing have attracted considerable attention. Several natural compounds have played crucial role in this intriguing process. The present study deals with five selected molecules from the plant Mallotus philippensis (Lam.) Mull. Arg. targeting the eight essential proteins involved in the wound healing and inflammatory process. Considering that various phytoconstituents of medicinal plant can simultaneously interacts with multiple targets, in current work multiligand and multitarget approach was employed instead of traditional one ligand-multitarget approach. Docking studies were performed using AutoDock Vina and molecular dynamics was performed using GROMACS 2019. The current study revealed the potential interactions of five selected constituents with multiple chronic wound healing targets. The wound healing effect of Mallotus philippensis (Lam.) Mull. Arg. fruits may be due to combined effect of all these compounds. Effective interactions with the amino acid residues present in the active site of some of the essential proteins involved in the wound healing process also suggests possible mechanism in the wound healing process. The current work thus provides a meaningful insight that Mallotus philippensis (Lam.) Mull. Arg. fruits could be used as potential candidate for faster healing of wound. Also, in silico studies depicting interaction with the targets and receptors provide a meaningful insight that this plant would be used as potential candidate for new drug development.

3.
Molecules ; 25(13)2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32630150

RESUMO

Tuberculosis (TB), caused by the bacterial organism Mycobacterium tuberculosis, pose a major threat to public health, especially in middle and low-income countries. Worldwide in 2018, approximately 10 million new cases of TB were reported to the World Health Organization (WHO). There are a limited number of medications available to treat TB; additionally, multi-drug resistant TB and extensively-drug resistant TB strains are becoming more prevalent. As a result of various factors, such as increased costs of developing new medications and adverse side effects from current medications, researchers continue to evaluate natural compounds for additional treatment options. These substances have the potential to target bacterial cell structures and may contribute to successful treatment. For example, a study reported that green and black tea, which contains epigallocatechin gallate (a phenolic antioxidant), may decrease the risk of contracting TB in experimental subjects; cumin (a seed from the parsley plant) has been demonstrated to improve the bioavailability of rifampicin, an important anti-TB medication, and propolis (a natural substance produced by honeybees) has been shown to improve the binding affinity of anti-TB medications to bacterial cell structures. In this article, we review the opportunistic pathogen M. tuberculosis, various potential therapeutic targets, available therapies, and natural compounds that may have anti-TB properties. In conclusion, different natural compounds alone as well as in combination with already approved medication regimens should continue to be investigated as treatment options for TB.


Assuntos
Antituberculosos/uso terapêutico , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/prevenção & controle , Antituberculosos/química , Humanos , Tuberculose/microbiologia
4.
Cells ; 9(7)2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32660081

RESUMO

To understand the mechanisms of disturbed differentiation and development by radiation, murine CGR8 embryonic stem cells (mESCs) were exposed to ionizing radiation and differentiated by forming embryoid bodies (EBs). The colony forming ability test was applied for survival and the MTT test for viability determination after X-irradiation. Cell cycle progression was determined by flow cytometry of propidium iodide-stained cells, and DNA double strand break (DSB) induction and repair by γH2AX immunofluorescence. The radiosensitivity of mESCs was slightly higher compared to the murine osteoblast cell line OCT-1. The viability 72 h after X-irradiation decreased dose-dependently and was higher in the presence of leukemia inhibitory factor (LIF). Cells exposed to 2 or 7 Gy underwent a transient G2 arrest. X-irradiation induced γH2AX foci and they disappeared within 72 h. After 72 h of X-ray exposure, RNA was isolated and analyzed using genome-wide microarrays. The gene expression analysis revealed amongst others a regulation of developmental genes (Ada, Baz1a, Calcoco2, Htra1, Nefh, S100a6 and Rassf6), downregulation of genes involved in glycolysis and pyruvate metabolism whereas upregulation of genes related to the p53 signaling pathway. X-irradiated mESCs formed EBs and differentiated toward cardiomyocytes but their beating frequencies were lower compared to EBs from unirradiated cells. These results suggest that X-irradiation of mESCs deregulate genes related to the developmental process. The most significant biological processes found to be altered by X-irradiation in mESCs were the development of cardiovascular, nervous, circulatory and renal system. These results may explain the X-irradiation induced-embryonic lethality and malformations observed in animal studies.


Assuntos
Células-Tronco Embrionárias Murinas/efeitos da radiação , Animais , Ciclo Celular , Diferenciação Celular , Linhagem Celular , Células Cultivadas , Quebras de DNA de Cadeia Dupla , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Miócitos Cardíacos/citologia , Transcriptoma , Raios X
5.
Acta Biomater ; 89: 180-192, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30862552

RESUMO

Pathophysiological conditions, such as myocardial infarction and mechanical overload affect the mammalian heart integrity, leading to a stiffened fibrotic tissue. With respect to the pathophysiology of cardiac fibrosis but also in the limelight of upcoming approaches of cardiac cell therapy it is of interest to decipher the interaction of cardiomyocytes with fibrotic matrix. Therefore, we designed a hydrogel-based model to engineer fibrotic tissue in vitro as an approach to predict the behavior of cardiomyocytes facing increased matrix rigidity. Here, we generated pure induced pluripotent stem cell-derived cardiomyocytes and cultured them on engineered polyacrylamide hydrogels matching the elasticities of healthy as well as fibrotic cardiac tissue. Only in cardiomyocytes cultured on matrices with fibrotic-like elasticity, transcriptional profiling revealed a substantial up-regulation of a whole panel of cardiac fibrosis-associated transcripts, including collagen I and III, decorin, lumican, and periostin. In addition, matrix metalloproteinases and their inhibitors, known to be essential in cardiac remodeling, were found to be elevated as well as insulin-like growth factor 2. Control experiments with primary cardiac fibroblasts were analyzed and did not show comparable behavior. In conclusion, we do not only present a snapshot on the transcriptomic fingerprint alterations in cardiomyocytes under pathological conditions but also provide a new reproducible approach to study the effects of fibrotic environments to various cell types. STATEMENT OF SIGNIFICANCE: The ageing population in many western countries is faced with an increasing burden of ageing-related diseases such as heart failure which is associated with cardiac fibrosis. A deeper understanding of the interaction of organotypic cells with altered extracellular matrix mechanical properties is of pivotal importance to understand the underlying mechanisms. Here, we present a strategy to combine hydrogel matrices with induced pluripotent stem cell derived cardiomyocytes to study the effect of matrix stiffening on these cells. Our findings suggest an active role of matrix stiffening on cardiomyocyte function and heart failure progression.


Assuntos
Proteínas da Matriz Extracelular/biossíntese , Matriz Extracelular/metabolismo , Hidrogéis/química , Miócitos Cardíacos/metabolismo , Regulação para Cima , Animais , Linhagem Celular , Fibrose , Camundongos , Miócitos Cardíacos/patologia
6.
Arch Toxicol ; 91(2): 839-864, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27188386

RESUMO

Stem cell-based in vitro test systems can recapitulate specific phases of human development. In the UKK test system, human pluripotent stem cells (hPSCs) randomly differentiate into cells of the three germ layers and their derivatives. In the UKN1 test system, hPSCs differentiate into early neural precursor cells. During the normal differentiation period (14 days) of the UKK system, 570 genes [849 probe sets (PSs)] were regulated >fivefold; in the UKN1 system (6 days), 879 genes (1238 PSs) were regulated. We refer to these genes as 'developmental genes'. In the present study, we used genome-wide expression data of 12 test substances in the UKK and UKN1 test systems to understand the basic principles of how chemicals interfere with the spontaneous transcriptional development in both test systems. The set of test compounds included six histone deacetylase inhibitors (HDACis), six mercury-containing compounds ('mercurials') and thalidomide. All compounds were tested at the maximum non-cytotoxic concentration, while valproic acid and thalidomide were additionally tested over a wide range of concentrations. In total, 242 genes (252 PSs) in the UKK test system and 793 genes (1092 PSs) in the UKN1 test system were deregulated by the 12 test compounds. We identified sets of 'diagnostic genes' appropriate for the identification of the influence of HDACis or mercurials. Test compounds that interfered with the expression of developmental genes usually antagonized their spontaneous development, meaning that up-regulated developmental genes were suppressed and developmental genes whose expression normally decreases were induced. The fraction of compromised developmental genes varied widely between the test compounds, and it reached up to 60 %. To quantitatively describe disturbed development on a genome-wide basis, we recommend a concept of two indices, 'developmental potency' (D p) and 'developmental index' (D i), whereby D p is the fraction of all developmental genes that are up- or down-regulated by a test compound, and D i is the ratio of overrepresentation of developmental genes among all genes deregulated by a test compound. The use of D i makes hazard identification more sensitive because some compounds compromise the expression of only a relatively small number of genes but have a high propensity to deregulate developmental genes specifically, resulting in a low D p but a high D i. In conclusion, the concept based on the indices D p and D i offers the possibility to quantitatively express the propensity of test compounds to interfere with normal development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Testes de Toxicidade/métodos , Transcriptoma/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Células-Tronco Embrionárias/efeitos dos fármacos , Humanos , Camundongos , Células-Tronco Pluripotentes/efeitos dos fármacos , Células-Tronco/fisiologia , Teratogênicos/toxicidade , Transcriptoma/genética
7.
Chem Res Toxicol ; 30(4): 905-922, 2017 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-28001369

RESUMO

Analysis of transcriptome changes has become an established method to characterize the reaction of cells to toxicants. Such experiments are mostly performed at compound concentrations close to the cytotoxicity threshold. At present, little information is available on concentration-dependent features of transcriptome changes, in particular, at the transition from noncytotoxic concentrations to conditions that are associated with cell death. Thus, it is unclear in how far cell death confounds the results of transcriptome studies. To explore this gap of knowledge, we treated pluripotent stem cells differentiating to human neuroepithelial cells (UKN1 assay) for short periods (48 h) with increasing concentrations of valproic acid (VPA) and methyl mercury (MeHg), two compounds with vastly different modes of action. We developed various visualization tools to describe cellular responses, and the overall response was classified as "tolerance" (minor transcriptome changes), "functional adaptation" (moderate/strong transcriptome responses, but no cytotoxicity), and "degeneration". The latter two conditions were compared, using various statistical approaches. We identified (i) genes regulated at cytotoxic, but not at noncytotoxic, concentrations and (ii) KEGG pathways, gene ontology term groups, and superordinate biological processes that were only regulated at cytotoxic concentrations. The consensus markers and processes found after 48 h treatment were then overlaid with those found after prolonged (6 days) treatment. The study highlights the importance of careful concentration selection and of controlling viability for transcriptome studies. Moreover, it allowed identification of 39 candidate "biomarkers of cytotoxicity". These could serve to provide alerts that data sets of interest may have been affected by cell death in the model system studied.


Assuntos
Compostos de Metilmercúrio/toxicidade , Transcriptoma/efeitos dos fármacos , Ácido Valproico/toxicidade , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Neurônios/citologia , Neurônios/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
J Glob Antimicrob Resist ; 5: 15-21, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27436460

RESUMO

Antimicrobial resistance severely limits the therapeutic options for many clinically important bacteria. In Gram-negative bacteria, multidrug resistance is commonly facilitated by plasmids that have the ability to accumulate and transfer refractory genes amongst bacterial populations. The aim of this study was to isolate and identify bioactive compounds from the medicinal plant Mallotus philippensis (Lam.) Mull. Arg. with both direct antibacterial properties and the capacity to inhibit plasmid conjugal transfer. A chloroform-soluble extract of M. philippensis was subjected to bioassay-guided fractionation using chromatographic and spectrometric techniques that led to the isolation of the known compounds rottlerin [5,7-dihydroxy-2,2-dimethyl-6-(2,4,6-trihydroxy-3-methyl-5-acetylbenzyl)-8-cinnamoyl-1,2-chromene] and the red compound (8-cinnamoyl-5,7-dihydroxy-2,2,6-trimethylchromene). Both compounds were characterised and elucidated using one-dimensional and two-dimensional nuclear magnetic resonance (NMR). Rottlerin and the red compound showed potent activities against a panel of clinically relevant Gram-positive bacteria, including meticillin-resistant Staphylococcus aureus (MRSA). No significant direct activities were observed against Gram-negative bacteria. However, both rottlerin and the red compound strongly inhibited conjugal transfer of the plasmids pKM101, TP114, pUB307 and R6K amongst Escherichia coli at a subinhibitory concentration of 100mg/L. Interestingly, despite the planar nature of the compounds, binding to plasmid DNA could not be demonstrated by a DNA electrophoretic mobility shift assay. These results show that rottlerin and the red compound are potential candidates for antibacterial drug lead development. Further studies are needed to elucidate the mode of inhibition of the conjugal transfer of plasmids.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Mallotus (Planta)/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenóis/farmacologia , Fatores R/genética , Acetofenonas/farmacologia , Benzopiranos/farmacologia , Escherichia coli/genética , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Extratos Vegetais
9.
Curr Med Chem ; 23(30): 3495-3509, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27356535

RESUMO

New drug discovery (NDD) is a fascinating discipline encompassing different facets of medicine, pharmacology, biotechnology and chemistry. NDD is very often restricted by efficacy or safety problems of the new clinical candidate in human patients. Drug regulatory authorities have provided various guidelines for advancement of safe new chemical entities (NCEs) in clinical trials which must be strictly followed. In spite of this, various drugs have failed in clinical trials or withdrawn from market because of human safety issues related to cardiotoxicity, hepatotoxicity, neurotoxicity and teratogenicity. The failure of safety prediction was pointed to species specificity issues, lack of mechanistic toxicity data and inadequate clinical trials. These drugs not only affect human health but also cause loss of resources and time. The species specificity issues are partially addressed by use of primary human cells but their availability is very limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) offer sources for generation of an unlimited number of human somatic cells. The emergence of mechanistic models for toxicity testing with transcriptomics, proteomics along with toxicokinetics readouts based on hESCs and hiPSCs is paving the way to design new human relevant testing strategies. Introduction of these models at the timeframe of lead selection and optimization in parallel with in vitro pharmacokinetic studies will significantly reduce compound attrition rate by selection of safer lead molecules. We focused on upcoming hESCs and hiPSCs based toxicity testing models and their future role to address safety gaps of present drug discovery and development.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Modelos Biológicos , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Pró-Fármacos/toxicidade , Testes de Toxicidade
10.
Cell Physiol Biochem ; 38(4): 1483-99, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27035921

RESUMO

BACKGROUND/AIMS: Embryonic developmental studies under microgravity conditions in space are very limited. To study the effects of altered gravity on the embryonic development processes we established an in vitro methodology allowing differentiation of mouse embryonic stem cells (mESCs) under simulated microgravity within a fast-rotating clinostat (clinorotation) and capture of microarray-based gene signatures. METHODS: The differentiating mESCs were cultured in a 2D pipette clinostat. The microarray and bioinformatics tools were used to capture genes that are deregulated by simulated microgravity and their impact on developmental biological processes. RESULTS: The data analysis demonstrated that differentiation of mESCs in pipettes for 3 days resultet to early germ layer differentiation and then to the different somatic cell types after further 7 days of differentiation in the Petri dishes. Clinorotation influences differentiation as well as non-differentiation related biological processes like cytoskeleton related 19 genes were modulated. Notably, simulated microgravity deregulated genes Cyr61, Thbs1, Parva, Dhrs3, Jun, Tpm1, Fzd2 and Dll1 are involved in heart morphogenesis as an acute response on day 3. If the stem cells were further cultivated under normal gravity conditions (1 g) after clinorotation, the expression of cardiomyocytes specific genes such as Tnnt2, Rbp4, Tnni1, Csrp3, Nppb and Mybpc3 on day 10 was inhibited. This correlated well with a decreasing beating activity of the 10-days old embryoid bodies (EBs). Finally, we captured Gadd45g, Jun, Thbs1, Cyr61and Dll1 genes whose expressions were modulated by simulated microgravity and by real microgravity in various reported studies. Simulated microgravity also deregulated genes belonging to the MAP kinase and focal dhesion signal transduction pathways. CONCLUSION: One of the most prominent biological processes affected by simulated microgravity was the process of cardiomyogenesis. The most significant simulated microgravity-affected genes, signal transduction pathways, and biological processes which are relevant for mESCs differentiation have been identified and discussed below.


Assuntos
Diferenciação Celular , Simulação de Ausência de Peso , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Animais , Proteínas de Ligação ao Cálcio , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Pontos de Checagem do Ciclo Celular , Proteína Rica em Cisteína 61/genética , Proteína Rica em Cisteína 61/metabolismo , Corpos Embrioides/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Miócitos Cardíacos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Plasmáticas de Ligação ao Retinol/genética , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Transcriptoma , Tropomiosina/genética , Tropomiosina/metabolismo , Troponina T/genética , Troponina T/metabolismo
11.
Stem Cell Res Ther ; 7(1): 190, 2016 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-28038682

RESUMO

BACKGROUND: Human embryonic stem cells (hESCs) partially recapitulate early embryonic three germ layer development, allowing testing of potential teratogenic hazards. Because use of hESCs is ethically debated, we investigated the potential for human induced pluripotent stem cells (hiPSCs) to replace hESCs in such tests. METHODS: Three cell lines, comprising hiPSCs (foreskin and IMR90) and hESCs (H9) were differentiated for 14 days. Their transcriptome profiles were obtained on day 0 and day 14 and analyzed by comprehensive bioinformatics tools. RESULTS: The transcriptomes on day 14 showed that more than 70% of the "developmental genes" (regulated genes with > 2-fold change on day 14 compared to day 0) exhibited variability among cell lines. The developmental genes belonging to all three cell lines captured biological processes and KEGG pathways related to all three germ layer embryonic development. In addition, transcriptome profiles were obtained after 14 days of exposure to teratogenic valproic acid (VPA) during differentiation. Although the differentially regulated genes between treated and untreated samples showed more than 90% variability among cell lines, VPA clearly antagonized the expression of developmental genes in all cell lines: suppressing upregulated developmental genes, while inducing downregulated ones. To quantify VPA-disturbed development based on developmental genes, we estimated the "developmental potency" (D p ) and "developmental index" (D i ). CONCLUSIONS: Despite differences in genes deregulated by VPA, uniform D i values were obtained for all three cell lines. Given that the D i values for VPA were similar for hESCs and hiPSCs, D i can be used for robust hazard identification, irrespective of whether hESCs or hiPSCs are used in the test systems.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Teratogênicos/farmacologia , Transcriptoma/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Camadas Germinativas/citologia , Camadas Germinativas/efeitos dos fármacos , Humanos , Regulação para Cima/efeitos dos fármacos
12.
ACS Med Chem Lett ; 6(12): 1190-4, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26713102

RESUMO

A new class of potent PI3Kα inhibitors is identified based on aryl substituted morpholino-triazine scaffold. The identified compounds showed not only a high level of enzymatic and cellular potency in nanomolar range but also high oral bioavailability. The three lead molecules (based on their in vitro potency) when evaluated further for in vitro metabolic stability as well as pharmacokinetic profile led to the identification of 26, as a candidate for further development. The IC50 and EC50 value of 26 is 60 and 500 nM, respectively, for PI3Kα enzyme inhibitory activity and ovarian cancer (A2780) cell line. The identified lead also showed a high level of microsomal stability and minimal inhibition activity for CYP3A4, CYP2C19, and CYP2D6 at 10 µM concentrations. The lead compound 26, demonstrated excellent oral bioavailability with an AUC of 5.2 µM at a dose of 3 mpk in mice and found to be well tolerated in mice when dosed at 30 mpk BID for 5 days.

13.
Methods Mol Biol ; 1250: 225-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26272146

RESUMO

Transcriptomics is a powerful tool for high-throughput gene expression profiling. Transcriptome microarray experiments conducted with RNA isolated from hepatocytes after exposure to toxicants enable a deep insight into the molecular mechanisms of hepatotoxicity. This understanding, along with structure-activity relationships underlying hepatotoxicity, will provide a novel strategy to design cost-effective and safer therapeutics. Transcriptomics studies conducted with established hepatotoxic drugs in various in vitro and in vivo hepatotoxicity test systems have contributed to the elucidation of the mechanistic basis of liver insults, which were later on substantiated at the proteomics and metabolomics levels. The present chapter is focused on comprehensive transcriptomics of cultured primary hepatocytes treated with chemicals by applying Affymetrix microarray technology. It also describes the detailed protocol for culturing of hepatocytes, their exposure to toxicants as well as sample collection, including RNA isolation, RNA target preparation and finally the hybridization to gene chips for microarray expression analysis.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Transcriptoma , Técnicas de Cultura de Células , Perfilação da Expressão Gênica/métodos , Humanos
14.
Arch Toxicol ; 89(9): 1599-618, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26272509

RESUMO

Test systems to identify developmental toxicants are urgently needed. A combination of human stem cell technology and transcriptome analysis was to provide a proof of concept that toxicants with a related mode of action can be identified and grouped for read-across. We chose a test system of developmental toxicity, related to the generation of neuroectoderm from pluripotent stem cells (UKN1), and exposed cells for 6 days to the histone deacetylase inhibitors (HDACi) valproic acid, trichostatin A, vorinostat, belinostat, panobinostat and entinostat. To provide insight into their toxic action, we identified HDACi consensus genes, assigned them to superordinate biological processes and mapped them to a human transcription factor network constructed from hundreds of transcriptome data sets. We also tested a heterogeneous group of 'mercurials' (methylmercury, thimerosal, mercury(II)chloride, mercury(II)bromide, 4-chloromercuribenzoic acid, phenylmercuric acid). Microarray data were compared at the highest non-cytotoxic concentration for all 12 toxicants. A support vector machine (SVM)-based classifier predicted all HDACi correctly. For validation, the classifier was applied to legacy data sets of HDACi, and for each exposure situation, the SVM predictions correlated with the developmental toxicity. Finally, optimization of the classifier based on 100 probe sets showed that eight genes (F2RL2, TFAP2B, EDNRA, FOXD3, SIX3, MT1E, ETS1 and LHX2) are sufficient to separate HDACi from mercurials. Our data demonstrate how human stem cells and transcriptome analysis can be combined for mechanistic grouping and prediction of toxicants. Extension of this concept to mechanisms beyond HDACi would allow prediction of human developmental toxicity hazard of unknown compounds with the UKN1 test system.


Assuntos
Inibidores de Histona Desacetilases/toxicidade , Placa Neural/efeitos dos fármacos , Células-Tronco Pluripotentes/efeitos dos fármacos , Transcriptoma , Perfilação da Expressão Gênica , Humanos , Placa Neural/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos
15.
J Vis Exp ; (100): e52333, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-26132533

RESUMO

Efficient protocols to differentiate human pluripotent stem cells to various tissues in combination with -omics technologies opened up new horizons for in vitro toxicity testing of potential drugs. To provide a solid scientific basis for such assays, it will be important to gain quantitative information on the time course of development and on the underlying regulatory mechanisms by systems biology approaches. Two assays have therefore been tuned here for these requirements. In the UKK test system, human embryonic stem cells (hESC) (or other pluripotent cells) are left to spontaneously differentiate for 14 days in embryoid bodies, to allow generation of cells of all three germ layers. This system recapitulates key steps of early human embryonic development, and it can predict human-specific early embryonic toxicity/teratogenicity, if cells are exposed to chemicals during differentiation. The UKN1 test system is based on hESC differentiating to a population of neuroectodermal progenitor (NEP) cells for 6 days. This system recapitulates early neural development and predicts early developmental neurotoxicity and epigenetic changes triggered by chemicals. Both systems, in combination with transcriptome microarray studies, are suitable for identifying toxicity biomarkers. Moreover, they may be used in combination to generate input data for systems biology analysis. These test systems have advantages over the traditional toxicological studies requiring large amounts of animals. The test systems may contribute to a reduction of the costs for drug development and chemical safety evaluation. Their combination sheds light especially on compounds that may influence neurodevelopment specifically.


Assuntos
Células-Tronco Pluripotentes/efeitos dos fármacos , Biologia de Sistemas/métodos , Testes de Toxicidade/métodos , Alternativas aos Testes com Animais/métodos , Humanos
16.
Cancer Sci ; 103(1): 88-99, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21943109

RESUMO

Alcoholic extract of Piper betle (Piper betle L.) leaves was recently found to induce apoptosis of CML cells expressing wild type and mutated Bcr-Abl with imatinib resistance phenotype. Hydroxy-chavicol (HCH), a constituent of the alcoholic extract of Piper betle leaves, was evaluated for anti-CML activity. Here, we report that HCH and its analogues induce killing of primary cells in CML patients and leukemic cell lines expressing wild type and mutated Bcr-Abl, including the T315I mutation, with minimal toxicity to normal human peripheral blood mononuclear cells. HCH causes early but transient increase of mitochondria-derived reactive oxygen species. Reactive oxygen species-dependent persistent activation of JNK leads to an increase in endothelial nitric oxide synthase-mediated nitric oxide generation. This causes loss of mitochondrial membrane potential, release of cytochrome c from mitochondria, cleavage of caspase 9, 3 and poly-adenosine diphosphate-ribose polymerase leading to apoptosis. One HCH analogue was also effective in vivo in SCID mice against grafts expressing the T315I mutation, although to a lesser extent than grafts expressing wild type Bcr-Abl, without showing significant bodyweight loss. Our data describe the role of JNK-dependent endothelial nitric oxide synthase-mediated nitric oxide for anti-CML activity of HCH and this molecule merits further testing in pre-clinical and clinical settings.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Eugenol/análogos & derivados , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , MAP Quinase Quinase 4/metabolismo , Mitocôndrias/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Piper betle/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/farmacologia , Benzamidas , Western Blotting , Eugenol/química , Eugenol/farmacologia , Citometria de Fluxo , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Camundongos SCID , Mitocôndrias/metabolismo , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Pirimidinas/farmacologia , Células Tumorais Cultivadas
17.
Front Biosci (Elite Ed) ; 3(4): 1349-64, 2011 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-21622141

RESUMO

Scientists are constantly searching for phytochemical compounds with anti-cancer activity. In this study, activity of plant extract NPB001-05 from Piper betle was tested on human chronic myelogenous leukemia (CML) xenograft models. NPB001-05 was active when dosed orally (500 mg/kg) once or twice a day in xenograft tumor models. NPB001-05 showed activity to T315I tumor xenograft, where imatinib failed to show antitumor activity. NPB001-05 showed no relevant toxicity in animal models during 2 weeks exposure to drug. Responsive tumor showed inhibition of tyrosine kinase activity with lowered Bcr-Abl protein levels and increased apoptosis. Microarray based transcription profiling studies demonstrated that both imatinib and NPB001-05 dysregulated imatinib- responsive genes. NPB001-05 showed additional genes selectively dysregulated from ER stress, PI3K/AKT, MAPK pathways. Additionally, we tested gene expression of PI3K, AKT1, JUN, CASP3 and DDIT3 in K562, BaF3P210(BCR-ABL) and BaF3 P210(BCR-ABLT315I) cell line treated for 6- and 12- hours with NPB001-05 and imatinib. The data indicates that NPB001-05 mediated cell death in K562 affects the function of ER stress. NPB001-05 shows antitumor activity with favorable toxicity profile.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Extratos Vegetais/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Sequência de Bases , Primers do DNA , Inibidores Enzimáticos/administração & dosagem , Humanos , Masculino , Camundongos , Camundongos SCID , Extratos Vegetais/administração & dosagem , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
J Chromatogr Sci ; 45(10): 706-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18078581

RESUMO

A simple, sensitive, and specific thin-layer chromatography densitometric method has been developed for the simultaneous quantitation of strychnine and brucine. These two marker compounds are quantitated in the seeds of Strychnos nux-vomica, Strychnos ignatii, and its formulations. The method involves densitometric evaluation of strychnine and brucine after resolving it by high-performance TLC on silica gel plate with toluene-ethyl acetate-diethyl amine-methanol (7:2:1:0.3 v/v) as the mobile phase. The method is validated for precision (interday and intraday), repeatability, and accuracy. The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 160 to 480 ng/spot for strychnine and 80 to 480 ng/spot for brucine. Instrumental precision is found to be 0.54 and 0.78 (% CV), and repeatability of the method is 1.01 and 1.06 (% CV) for strychnine and brucine, respectively. Accuracy of the method is checked by recovery study conducted at three different levels and the average percentage recovery is found to be 99.13% for strychnine and 100.16% for brucine. The proposed HPTLC method for the simultaneous quantitation of strychnine and brucine is found to be simple, precise, specific, sensitive, and accurate, and it can be used for routine quality control of raw material of Strychnos spp. It also can be applied in quantitating any of these marker compounds in other formulations.


Assuntos
Cromatografia em Camada Fina/métodos , Densitometria/métodos , Estricnina/análogos & derivados , Estricnina/análise , Strychnos/química , Padrões de Referência , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
19.
J Sep Sci ; 30(13): 2053-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17628870

RESUMO

The term 'phenolics' refers to a vast array of biologically active compounds ubiquitous in plants, many of which have been used in traditional medicine for thousands of years. Umbelliferone, psoralen, and eugenol are widely occurring phenolic compounds of plant origin, for which many biological activities against chronic diseases have been reported. A simple HPTLC method has been developed for the simultaneous quantification of umbelliferone, psoralen, and eugenol. These three compounds were quantified in the dried fruit pulp of Aegle marmelos and in the fruit of Trachyspermum ammi and Foeniculam vulgare. The technique enables rapid and sensitive simultaneous analysis in different samples. The method was validated for precision, repeatability, and accuracy in accordance with ICH guidelines. The accuracy of the method was checked by a recovery study conducted at three different levels and the average percentage recovery was found to be 98.88% for umbelliferone, 100.104% for psoralen, and 99.33% for eugenol. The proposed HPTLC method for the simultaneous quantification of umbelliferone, psoralen, and eugenol was found to be simple, precise, specific, sensitive, and accurate. It can be used for routine quality control of herbal raw materials as well as formulations containing any or all of these compounds.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Densitometria/métodos , Eugenol/análise , Ficusina/análise , Plantas Medicinais/química , Umbeliferonas/análise , Aegle/química , Foeniculum/química , Frutas/química , Teste de Materiais , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química
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