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1.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473980

RESUMO

Liver fibrosis poses a significant global health risk due to its association with hepatocellular carcinoma (HCC) and the lack of effective treatments. Thus, the need to discover additional novel therapeutic targets to attenuate liver diseases is urgent. Leucine-rich repeat containing 1 (LRRC1) reportedly promotes HCC development. Previously, we found that LRRC1 was significantly upregulated in rat fibrotic liver according to the transcriptome sequencing data. Herein, in the current work, we aimed to explore the role of LRRC1 in liver fibrosis and the underlying mechanisms involved. LRRC1 expression was positively correlated with liver fibrosis severity and significantly elevated in both human and murine fibrotic liver tissues. LRRC1 knockdown or overexpression inhibited or enhanced the proliferation, migration, and expression of fibrogenic genes in the human hepatic stellate cell line LX-2. More importantly, LRRC1 inhibition in vivo significantly alleviated CCl4-induced liver fibrosis by reducing collagen accumulation and hepatic stellate cells' (HSCs) activation in mice. Mechanistically, LRRC1 promoted HSC activation and liver fibrogenesis by preventing the ubiquitin-mediated degradation of phosphorylated mothers against decapentaplegic homolog (Smad) 2/3 (p-Smad2/3), thereby activating the TGF-ß1/Smad pathway. Collectively, these results clarify a novel role for LRRC1 as a regulator of liver fibrosis and indicate that LRRC1 is a promising target for antifibrotic therapies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratos , Humanos , Camundongos , Animais , Células Estreladas do Fígado/metabolismo , Leucina/metabolismo , Regulação para Cima , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Cirrose Hepática/metabolismo , Fígado/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Smad/metabolismo
2.
Toxicol Appl Pharmacol ; 327: 1-12, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28438631

RESUMO

It is well known that liver cancer is a highly aggressive malignancy with poor prognosis. Andrographolide (AD), a major bioactive component of Andrographis paniculata (Burm. F.), is a potential anti-cancer pharmacophore and the synthesis of AD derivatives with better cytotoxicity to cancer cells has attracted considerable attentions. In the present study, we evaluated the in vivo inhibitory effects of ADN-9, a 15-benzylidene substituted derivative of AD, on the growth and metastasis of murine hepatoma H22 using an orthotopic xenograft model and a subcutaneous xenograft model, and we further studied the anti-angiogenic action and the related mechanisms of ADN-9 in vivo and in vitro. Importantly, ADN-9 remarkably suppressed the growth and metastasis of both orthotopic and subcutaneous xenograft tumors, and the serum AFP level in orthotopic hepatoma-bearing mice treated with 100mg/kg ADN-9 (ig.) was decreased to the normal level. We also found that ADN-9 showed stronger abilities than AD in shrinking tumors, suppressing the invasion and metastasis of H22 cells, decreasing the MVD and promoting tumor cell apoptosis in subcutaneous xenograft of mice. Additionally, ADN-9 exhibited stronger inhibitory activity than AD against the migration and VEGF-induced capillary-like tube formation in HUVECs, which was further proved to be associated with attenuating VEGF/VEGFR2/AKT signaling pathway. The present research provides the first evidence that a 15-substituted AD derivative is more promising than the parent compound in therapeutic treatment of liver cancer.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/farmacologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Andrographis/química , Animais , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Circulação Hepática/efeitos dos fármacos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas Experimentais/irrigação sanguínea , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica/patologia , Metástase Neoplásica , Neovascularização Patológica/patologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Cicatrização/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Chem Biodivers ; 12(5): 813-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26010668

RESUMO

The synthesis of [(2',5'-dihydrofuran-2-yl)oxy]methyl-phosphonate nucleosides with a 2-substituted adenine base moiety starting from 2-deoxy-3,5-bis-O-(4-methylbenzoyl)-α-L-ribofuranosyl chloride and 2,6-dichloropurine is described. The key step is the regiospecific and stereoselective introduction of a phosphonate synthon at C(2) of the furan ring. None of the synthesized compounds showed significant in vitro activity against HIV, BVDV, and HBV.


Assuntos
Adenina/química , Antivirais/síntese química , Antivirais/farmacologia , Organofosfonatos/química , Organofosfonatos/farmacologia , Nucleosídeos de Purina/química , Nucleosídeos de Purina/farmacologia , Antivirais/química , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Relação Dose-Resposta a Droga , HIV/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Organofosfonatos/síntese química , Nucleosídeos de Purina/síntese química
4.
Bioorg Med Chem Lett ; 24(10): 2388-91, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24745970

RESUMO

In this study we report the synthesis and activity against bovine viral diarrhea virus (BVDV) of a novel series of bicycle δ-sultones containing γ-lactones. BVDV is responsible for major losses in cattle. Some of the synthesized δ-sultones showed pronounced anti-BVDV activity with EC50 values of 0.12-1.0µM and no significant cytotoxicity. Among them, the ortho bromosubstituted derivative 4f (EC50=0.12µM) showed better antiviral activity than other derivatives and was 10 fold more that of than positive control ribavirin (EC50=1.3µM). BVDV is also considered to be a valuable surrogate for the hepatitis C virus (HCV) in antiviral drug studies. The above results provided a novel candidate for the development of anti-HCV agents.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Animais , Bovinos , Modelos Animais de Doenças , Desenho de Fármacos
5.
Biochim Biophys Acta Mol Basis Dis ; 1870(4): 167054, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38360074

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors and is a serious threat to human health; thus, early diagnosis and adequate treatment are essential. However, there are still great challenges in identifying the tipping point and detecting early warning signals of early HCC. In this study, we aimed to identify the tipping point (critical state) of and key molecules involved in hepatocarcinogenesis based on time series transcriptome expression data of HCC patients. The phase from veHCC (very early HCC) to eHCC (early HCC) was identified as the critical state in HCC progression, with 143 genes identified as key candidate molecules by combining the DDRTree (dimensionality reduction via graph structure learning) and DNB (dynamic network biomarker) methods. Then, we ranked the candidate genes to verify their mRNA levels using the diethylnitrosamine (DEN)-induced HCC mouse model and identified five early warning signals, namely, CCT3, DSTYK, EIF3E, IARS2 and TXNRD1; these signals can be regarded as the potential early warning signals for the critical state of HCC. We identified CCT3 as an independent prognostic factor for HCC, and functions of CCT3 involving in the "MYCtargets_V1" and "E2F-Targets" are closely related to the progression of HCC. The predictive method combining the DDRTree and DNB methods can not only identify the key critical state before cancer but also determine candidate molecules of critical state, thus providing new insight into the early diagnosis and preemptive treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Carcinogênese/genética , Carcinogênese/patologia , Biomarcadores , Transcriptoma , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Chaperonina com TCP-1/genética , Chaperonina com TCP-1/metabolismo
6.
Bioorg Med Chem Lett ; 23(23): 6421-6, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24120543

RESUMO

In the present study, andrographolide (Andro, 1) derivatives were screened to identify potent inhibitors against tumor-cell migration and invasion, and associated structure-activity relationships were studied. Compared to 1, compounds 8a-8d exhibited more potent activities against migration in SGC-7901, PC-3, A549, HT-29 and Ec109 cell lines. Improved activities against tumor-cell migration and invasion were proved to be associated with the down-regulation of MMPs.


Assuntos
Movimento Celular/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacologia , Neoplasias/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Diterpenos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Neoplasias/patologia , Relação Estrutura-Atividade
7.
Front Pharmacol ; 13: 1079566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36569318

RESUMO

Background: Although immune microenvironment-related chemokines, extracellular matrix (ECM), and intrahepatic immune cells are reported to be highly involved in hepatitis B virus (HBV)-related diseases, their roles in diagnosis, prognosis, and drug sensitivity evaluation remain unclear. Here, we aimed to study their clinical use to provide a basis for precision medicine in hepatocellular carcinoma (HCC) via the amalgamation of artificial intelligence. Methods: High-throughput liver transcriptomes from Gene Expression Omnibus (GEO), NODE (https://www.bio.sino.org/node), the Cancer Genome Atlas (TCGA), and our in-house hepatocellular carcinoma patients were collected in this study. Core immunosignals that participated in the entire diseases course of hepatitis B were explored using the "Gene set variation analysis" R package. Using ROC curve analysis, the impact of core immunosignals and amino acid utilization related gene on hepatocellular carcinoma patient's clinical outcome were calculated. The utility of core immunosignals as a classifier for hepatocellular carcinoma tumor tissue was evaluated using explainable machine-learning methods. A novel deep residual neural network model based on immunosignals was constructed for the long-term overall survival (LS) analysis. In vivo drug sensitivity was calculated by the "oncoPredict" R package. Results: We identified nine genes comprising chemokines and ECM related to hepatitis B virus-induced inflammation and fibrosis as CLST signals. Moreover, CLST was co-enriched with activated CD4+ T cells bearing harmful factors (aCD4) during all stages of hepatitis B virus pathogenesis, which was also verified by our hepatocellular carcinoma data. Unexpectedly, we found that hepatitis B virus-hepatocellular carcinoma patients in the CLSThighaCD4high subgroup had the shortest overall survival (OS) and were characterized by a risk gene signature associated with amino acids utilization. Importantly, characteristic genes specific to CLST/aCD4 showed promising clinical relevance in identifying patients with early-stage hepatocellular carcinoma via explainable machine learning. In addition, the 5-year long-term overall survival of hepatocellular carcinoma patients can be effectively classified by CLST/aCD4 based GeneSet-ResNet model. Subgroups defined by CLST and aCD4 were significantly involved in the sensitivity of hepatitis B virus-hepatocellular carcinoma patients to chemotherapy treatments. Conclusion: CLST and aCD4 are hepatitis B virus pathogenesis-relevant immunosignals that are highly involved in hepatitis B virus-induced inflammation, fibrosis, and hepatocellular carcinoma. Gene set variation analysis derived immunogenomic signatures enabled efficient diagnostic and prognostic model construction. The clinical application of CLST and aCD4 as indicators would be beneficial for the precision management of hepatocellular carcinoma.

8.
Int Immunopharmacol ; 112: 109201, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36067652

RESUMO

Tubulointerstitial fibrosis (TIF) is a prominent pathological manifestation for the progression of almost all chronic kidney diseases (CKDs) to end-stage renal failure. However, there exist few efficient therapies to cure TIF. Our recent results showed that (8R, 12S)-isoandrographolide (ISA), a diterpenoid lactone ingredient of traditional Chinese herbal Andrographis paniculata (Burm.f.) Nees, exhibited anti-pulmonary fibrosis in silica-induced mice. Herein, we investigated the therapeutic effect of ISA on TIF, using mice subjected to unilateral ureteral obstruction (UUO) and human kidney proximal tubular epithelial (HK-2) cells treated with transforming growth factor-ß1 (TGF-ß1) or tumor necrosis factor-α (TNF-α). The pathological changes and collagen deposition results displayed that ISA administration significantly attenuated inflammatory response, ameliorated TIF, and protected the kidney injury. Interestingly, ISA revealed much lower cytotoxicity on HK-2 cells, but exhibited stronger inhibitory effect on tubular epithelial mesenchymal transformation (EMT) and inflammation, as compared to andrographolide (AD), the major ingredient of A. paniculata extract that has been reported to ameliorate TIF in diabetic nephropathy mice. It was further clarified that the amelioration of TIF by ISA was associated with suppressing the aberrant activation of AKT/GSK-3ß/ß-catenin pathway through network pharmacology analysis and experimental validation. Taken together, these findings indicate that ISA is a promising lead compound for development of anti-TIF, and even broad-spectrum anti-fibrotic drugs.


Assuntos
Nefropatias Diabéticas , Diterpenos , Obstrução Ureteral , Animais , Humanos , Camundongos , Andrographis paniculata , beta Catenina/metabolismo , Nefropatias Diabéticas/metabolismo , Diterpenos/uso terapêutico , Diterpenos/farmacologia , Transição Epitelial-Mesenquimal , Fibrose , Glicogênio Sintase Quinase 3 beta/metabolismo , Lactonas/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Dióxido de Silício , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/complicações
9.
Int Immunopharmacol ; 105: 108539, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35063750

RESUMO

Silicosis is an irreversible occupational disease caused by silica particle exposure. Abundant evidences suggest that NLRP3-mediated inflammation acts an essential role in fibrogenesis and the pathogenesis of silicosis. In the current work, we firstly reported that (8R-12S)-isoandrographolide (ISA), a diterpenoid lactone ingredient of Chinese traditional medicinal plant Andrographis paniculata (Burm.f.) Nees, could reduce pulmonary inflammation and fibrosis by inhibiting NLRP3, and thereby ameliorate silicosis. ISA administration significantly alleviated lung injury, and attenuated inflammatory response, EMT, as well as collagen deposition in the lung of silica-induced mice. Further studies verified that ISA inhibited the expressions of NLRP3 inflammasome-related proteins NLRP3, ASC and caspase-1 in vivo and in vitro, leading to the attenuation of inflammation and EMT. Additionally, the molecular docking assay indicated that ISA possibly interacted with the residues of LYS26 and GLU47 of NLRP3, implying that ISA might directly bond to protein NLRP3. Of note, ISA revealed a lower cytotoxicity but more potent therapeutic effect than andrographolide (AD), the major active extract of A. paniculata, which has been traditionally used to treat inflammation-related diseases. Taken together, our study clarified a novel role of ISA in attenuating inflammation and fibrosis in silicosis, and indicated a bright future of ISA as a lead compound for developing therapeutic drug for silicosis.


Assuntos
Diterpenos , Silicose , Animais , Diterpenos/farmacologia , Diterpenos/uso terapêutico , Inflamassomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Silicose/tratamento farmacológico
10.
Bioorg Med Chem Lett ; 19(23): 6637-9, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19864129

RESUMO

A series of novel 3beta, 7alpha, 11alpha-trihydroxy-pregn-21-benzylidene-5-en-20-one derivatives were synthesized and characterized by NMR, HRMS. The pregnenolone (1) was first biotransformed by Mucor circinelloides var lusitanicus to 3beta, 7alpha, 11alpha-trihydroxy-pregn-5-en-20-one (3), then 3 was treated with various benzaldehydes to produce 3beta, 7alpha, 11alpha-trihydroxy-pregn-21-benzylidene-5-en-20-one derivatives. These derivatives showed remarkable activity against EC109 cells. The absolute configuration of 3 was also confirmed by signal-crystal X-ray analysis.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Pregnenolona/análogos & derivados , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Mucor/metabolismo , Pregnenolona/síntese química , Pregnenolona/química , Pregnenolona/farmacologia , Relação Estrutura-Atividade
11.
Bioorg Med Chem Lett ; 19(6): 1818-21, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19223180

RESUMO

By means of functional interconversions in ring D of the tetracyclic diterpene isosteviol (ent-16-ketobeyeran-19-oic acid 1), various 15- and 16-substituted isosteviol derivatives were stereoselectively prepared. The cytotoxic activities in vitro of these new isosteviol derivatives were investigated, and some of them showed noteworthy activities against B16-F10 melanoma cells.


Assuntos
Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/farmacologia , Animais , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Simulação por Computador , Cristalografia por Raios X/métodos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Melanoma Experimental/tratamento farmacológico , Camundongos , Modelos Químicos , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
12.
Bioorg Med Chem ; 17(4): 1464-73, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19167896

RESUMO

Considerable interest has been attracted in isosteviol and its derivatives because of their large variety of pharmacological activities. In this project, a series of novel compounds containing hydroxyl, hydroxymethyl group and heteroatom-containing frameworks fused with isosteviol structure were synthesized and evaluated as alpha-glucosidase inhibitors, aimed at clarifying the structure-activity correlation. The results indicated that these isosteviol derivatives were capable of inhibiting in vitro alpha-glucosidase with moderate to good activities. Among them, indole derivative 15b exhibited the highest activities and thus may be exploitable as a lead compound for the development of potent alpha-glucosidase inhibitors.


Assuntos
Diterpenos do Tipo Caurano/síntese química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Cristalografia por Raios X , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Inibidores Enzimáticos/química , Hidroxilação , Indóis/síntese química , Indóis/química , Indóis/farmacologia , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Relação Estrutura-Atividade
13.
Bioresour Technol ; 193: 331-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26143000

RESUMO

To prepare fermentable hydrolysate from corncob residue (CCR), Trichoderma strain G26 was cultured on medium containing CCR for production of cellulolytic enzymes through solid-state fermentation (SSF), resulting in 71.3 IU/g (FPA), 136.2 IU/g (CMCase), 85.1 IU/g (ß-glucosidase) and 11,344 IU/g (xylanase), respectively. Through a three-stage saccharification strategy, CCR was hydrolyzed by the enzymatic solution (6.5 FPU/ml) into fermentable hydrolysate containing 60.1g/l glucose (81.2% cellulose was converted at solid loading of 12.5%), 21.4% higher than that by the one-stage method. And then the hydrolysate was used to produce L-lactic acid by a previous screened strain Bacillus coagulans ZX25 in the submerged fermentation. 52.0 g/l L-lactic acid was obtained after fermentation for 44 h, with 86.5% glucose being converted to L-lactic acid. The results indicate that the strains and the hydrolysis strategy are promising for commercial production of L-lactic acid from CCR and other biomass.


Assuntos
Celulase/metabolismo , Celulose/metabolismo , Ácido Láctico/biossíntese , Trichoderma/enzimologia , Resíduos/análise , Zea mays/química , Metabolismo dos Carboidratos/efeitos dos fármacos , Fermentação/efeitos dos fármacos , Hidrólise/efeitos dos fármacos , Tensoativos/farmacologia , Fatores de Tempo
14.
Int Immunopharmacol ; 11(12): 2144-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21983643

RESUMO

Andrographolide (1) is a major diterpene lactone exhibiting anti-inflammatory effects and is found in the plant Andrographis paniculata (Burm. f) Nees, which is widely used in Traditional Chinese Medicine. Synthesis of more effective drugs from andrographolide is very interesting and can prove to be highly useful. In this study, we investigated the anti-inflammatory effects of andrographolide and its derivatives (compounds 2-6) through dimethylbenzene-induced ear edema in mice. Substances under study were administrated intragastrically and the structure-activity relationship was analyzed. Results showed that compounds 5 and 6 significantly inhibited ear edema compared with compound 1 (p<0.05), indicating that the introduction of p-Chlorobenzylidene to C-15 of compound 2 enhances the anti-inflammatory effect. Moreover, compound 6 exhibited the strongest anti-inflammatory effect against ear edema in mice (79.4%; 1.35 mmol/kg, ig) and paw edema in rats (50.4%; 0.90 mmol/kg, ig). In addition, compound 6 significantly (p<0.05) inhibited granuloma formation and reduced the increase in vascular permeability induced by peritoneal injection of 0.6% acetic acid solution in mice. Findings indicate that compound 6 exerts its enhanced anti-inflammatory effects by decreasing serum iNOS activity, NO production, and PGE(2) production.


Assuntos
Anti-Inflamatórios/farmacologia , Dinoprostona/biossíntese , Diterpenos/química , Diterpenos/farmacologia , Otopatias/tratamento farmacológico , Edema/tratamento farmacológico , Óxido Nítrico/biossíntese , Animais , Compostos de Benzilideno , Otopatias/induzido quimicamente , Edema/induzido quimicamente , Granuloma/tratamento farmacológico , Masculino , Camundongos , Óxido Nítrico Sintase Tipo II/sangue , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Xilenos/toxicidade
15.
Sheng Wu Gong Cheng Xue Bao ; 25(4): 626-31, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19637642

RESUMO

A recombinant strain Escherichia coli DH5alpha(pMD19-glnA) including Bacillus subtilis glnA gene was constructed. Capillary electrophoresis and nuclear magnetic resonance were used to determine qualitatively the product of transformation by recombinant strain, and the relative level of mRNA expression of glnA was also determined by fluorescence quantitative RT-PCR. Subsequently, SDS-PAGE (polyacrylamide gel electrophoresis) was used to analysis the relative level of protein. Surprisingly, there was no increase of glutamine production in this recombinant strain, but an obvious increase in the GABA (gamma-aminobutyric acid ) production. It was showed in the experiment that protein expression of the glutamine synthetase did not increase, although glnA gene can be transcribed normally in this recombined strain. The phenomenon of exogenous glnA gene interfering metabolism of Escherichia coli was worthy of further study.


Assuntos
Bacillus subtilis/genética , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Glutamato-Amônia Ligase/genética , Proteínas de Bactérias/metabolismo , Glutamato-Amônia Ligase/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recombinação Genética , Ácido gama-Aminobutírico/biossíntese
16.
Bioorg Med Chem Lett ; 17(12): 3454-7, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17462891

RESUMO

Condensation of a new unnatural sugar 1 with 1,3-dicarbonyl compounds in the presence of anhydrous zinc chloride gave the polyhydroxyalkyl-furans in excellent yields. Further modification afforded the corresponding furanosyl alpha-C-glycoside derivatives. The absolute configuration of 3-acetyl-2-methyl-5-(2'-chloro-D-galacto-tetritol-1-yl)-furan was confirmed by single-crystal X-ray analysis. The in vitro cytotoxic activities of these furanosyl C-glycosides were also investigated.


Assuntos
Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Fucose/análogos & derivados , Furanos/química , Glicosídeos/farmacologia , Neoplasias Pulmonares/patologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral/efeitos dos fármacos , Cloretos/química , Fucose/química , Glicosídeos/síntese química , Humanos , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade , Compostos de Zinco/química
18.
Bioorg Med Chem Lett ; 17(3): 609-12, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17110108

RESUMO

A novel and efficient method for the synthesis of quinoxaline derivatives has been developed. Isopropylidenation of 4-chloro-4-deoxy-alpha-D-galactose with 2,2-dimethoxypropane, followed by selective hydrolysis, afforded 2,3-O-isopropylidene-4-chloro-4-deoxy-D-galactose di-methyl acetal (3) as a sole product. Oxidation of compound 3 with (Bu3Sn)2O-Br2 gave corresponding hex-5-ulose derivative in high yields. The hex-5-ulose derivative reacted with o-phenylenediamines under neutral conditions to afford quinoxaline derivatives in reasonable yields. The in vitro cytotoxic activities of these quinoxaline derivatives were investigated.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Fucose/análogos & derivados , Quinoxalinas/síntese química , Quinoxalinas/farmacologia , Carboidratos/química , Linhagem Celular Tumoral , Fucose/síntese química , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Relação Estrutura-Atividade , Sais de Tetrazólio , Tiazóis
19.
Bioorg Med Chem ; 15(12): 4247-55, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17428667

RESUMO

Andrographolide (1), the cytotoxic agent of the plant Andrographis paniculata, was subjected to semi-synthetic studies leading to a series of new derivatives, a novel family of glucosidase inhibitors. Nicotination of 3,19-hydroxyls in 15-alkylidene andrographolide derivatives (9) was favorable to alpha-glucosidase inhibition activity. Among them, 15-p-chlorobenzylidene-14-deoxy-11,12-didehydro-3,19-dinicotinateandrographolide (11c) was a very potent inhibitor against alpha-glucosidase with an IC50 value of 6 microM. However, all compounds concerned for beta-glucosidase showed no inhibition. All compounds synthesized were characterized by the analysis of NMR, IR, HRMS spectra and the stereochemistry of 2 was confirmed by X-ray analysis.


Assuntos
Diterpenos/síntese química , Inibidores Enzimáticos/síntese química , Inibidores de Glicosídeo Hidrolases , Andrographis/química , Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Modelos Moleculares , Espectrofotometria Infravermelho , Estereoisomerismo
20.
Bioorg Med Chem Lett ; 16(10): 2710-3, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16504503

RESUMO

A series of analogues of andrographolide were synthesized and evaluated as novel alpha-glucosidase inhibitors. Among them compound 23, 15-p-methoxylbenzylidene 14-deoxy-11,12-didehydroandrographolide, was a potent inhibitor against alpha-glucosidase whose IC(50) value was 16microM. The structure-activity relationships were also discussed.


Assuntos
Diterpenos/química , Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores de Glicosídeo Hidrolases , Animais , Ratos , Relação Estrutura-Atividade
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