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1.
Bioorg Chem ; 147: 107412, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38696845

RESUMO

The development of novel topoisomerase I (TOP1) inhibitors is crucial for overcoming the drawbacks and limitations of current TOP1 poisons. Here, we identified two potential TOP1 inhibitors, namely, FTY720 (a sphingosine 1-phosphate antagonist) and COH29 (a ribonucleotide reductase inhibitor), through experimental screening of known active compounds. Biological experiments verified that FTY720 and COH29 were nonintercalative TOP1 catalytic inhibitors that did not induce the formation of DNA-TOP1 covalent complexes. Molecular docking revealed that FTY720 and COH29 interacted favorably with TOP1. Molecular dynamics simulations revealed that FTY720 and COH29 could affect the catalytic domain of TOP1, thus resulting in altered DNA-binding cavity size. The alanine scanning and interaction entropy identified Arg536 as a hotspot residue. In addition, the bioinformatics analysis predicted that FTY720 and COH29 could be effective in treating malignant breast tumors. Biological experiments verified their antitumor activities using MCF-7 breast cancer cells. Their combinatory effects with TOP1 poisons were also investigated. Further, FTY720 and COH29 were found to cause less DNA damage compared with TOP1 poisons. The findings provide reliable lead compounds for the development of novel TOP1 catalytic inhibitors and offer new insights into the potential clinical applications of FTY720 and COH29 in targeting TOP1.


Assuntos
Antineoplásicos , DNA Topoisomerases Tipo I , Cloridrato de Fingolimode , Simulação de Acoplamento Molecular , Inibidores da Topoisomerase I , Humanos , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/química , Cloridrato de Fingolimode/síntese química , DNA Topoisomerases Tipo I/metabolismo , DNA Topoisomerases Tipo I/química , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/síntese química , Estrutura Molecular , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Simulação de Dinâmica Molecular , Células MCF-7
2.
Eur J Med Chem ; 265: 116078, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38141286

RESUMO

In this study, ligands 2-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline (PIP), 2-(2-nitrophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (NPIP), 2-(2-nitronaphthalen-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (NNIP) and their iridium(III) metal compounds [Ir(ppy)2(PIP)](PF6) (ppy = 2-phenylpyridine, 1a), [Ir(ppy)2(NPIP)](PF6) (1b), [Ir(ppy)2(NNIP)](PF6) (1c) were designed and synthesized. The anti-cancer activities of 1a, 1b and 1c on BEL-7402, HepG2, SK-Hep1 and non-cancer LO2 were detected using MTT method. 1a shows moderate, 1b and 1c display low or no anti-cancer activities. To elevate the anti-cancer effectiveness, encapsulating the compounds 1a, 1b and 1c into the ordinary or targeted liposomes to produce 1alip, 1blip, 1clip, or targeted 1aTlip, 1bTlip and 1cTlip. The IC50 values of 1alip, 1blip, 1clip, 1aTlip, 1bTlip and 1cTlip against HepG2 cells are 7.9 ± 0.1, 8.6 ± 0.2, 16.9 ± 0.5, 5.9 ± 0.2, 7.3 ± 0.1 and 9.7 ± 0.7 µM, respectively. Specifically, the anti-tumor activity assays in vivo found that the inhibitory rates are 23.24 % for 1a, 61.27 % for 1alip, 76.06 % for 1aTlip. It is obvious that the targeted liposomes entrapped iridium(III) compound greatly enhance anti-cancer efficacy. Additionally, 1alip, 1blip and 1clip or targeted 1aTlip, 1bTlip and 1cTlip can effectively restrain the cell colony and proliferation in the G0/G1 period. 1alip, 1blip, 1clip, 1aTlip, 1bTlip and 1cTlip can increase reactive oxygen species (ROS) concentration, arouse a decline in the mitochondrial membrane potential and promote Ca2+ release. RNA-sequence was applied to examine the signaling pathways. Taken together, the liposomes or targeted liposomes encapsulated compounds trigger cell death by way of apoptosis, autophagy, ferroptosis, disruption of mitochondrial function and PI3K/AKT/mTOR signaling pathways.


Assuntos
Antineoplásicos , Complexos de Coordenação , Ferroptose , Fosfatos de Inositol , Humanos , Células Hep G2 , Lipossomos , Linhagem Celular Tumoral , Irídio/farmacologia , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Fenantrolinas/farmacologia , Fosfatidilinositol 3-Quinases/farmacologia , Complexos de Coordenação/farmacologia , Antineoplásicos/farmacologia , Apoptose , Espécies Reativas de Oxigênio/metabolismo
3.
EBioMedicine ; 96: 104798, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37713809

RESUMO

BACKGROUND: Asthenozoospermia is the primary cause of male infertility; however, its genetic aetiology remains poorly understood. Adenylate kinase 9 (AK9) is highly expressed in the testes of humans and mice and encodes a type of adenosine kinase that is functionally involved in cellular nucleotide homeostasis and energy metabolism. We aimed to assess whether AK9 is involved in asthenozoospermia. METHODS: One-hundred-and-sixty-five Chinese men with idiopathic asthenozoospermia were recruited. Whole-exome sequencing (WES) and Sanger sequencing were performed for genetic analyses. Papanicolaou staining, Haematoxylin and eosin staining, scanning electron microscopy, and transmission electron microscopy were used to observe the sperm morphology and structure. Ak9-knockout mice were generated using CRISPR-Cas9. Sperm adenosine was detected by liquid chromatography-mass spectrometry. Targeted sperm metabolomics was performed. Intracytoplasmic sperm injection (ICSI) was used to treat patients. FINDINGS: We identified five patients harbouring bi-allelic AK9 mutations. Spermatozoa from men harbouring bi-allelic AK9 mutations have a decreased ability to sustain nucleotide homeostasis. Moreover, bi-allelic AK9 mutations inhibit glycolysis in sperm. Ak9-knockout male mice also presented similar phenotypes of asthenozoospermia. Interestingly, ICSI was effective in bi-allelic AK9 mutant patients in achieving good pregnancy outcomes. INTERPRETATION: Defects in AK9 induce asthenozoospermia with defects in nucleotide homeostasis and energy metabolism. This sterile phenotype could be rescued by ICSI. FUNDING: The National Natural Science Foundation of China (82071697), Medical Innovation Project of Fujian Province (2020-CXB-051), open project of the NHC Key Laboratory of Male Reproduction and Genetics in Guangzhou (KF202004), Medical Research Foundation of Guangdong Province (A2021269), Guangdong Provincial Reproductive Science Institute Innovation Team grants (C-03), and Outstanding Young Talents Program of Capital Medical University (B2205).


Assuntos
Astenozoospermia , Infertilidade Masculina , Humanos , Gravidez , Feminino , Masculino , Animais , Camundongos , Astenozoospermia/genética , Astenozoospermia/metabolismo , Nucleotídeos/metabolismo , Sêmen , Espermatozoides , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo
4.
Bioorg Chem ; 139: 106734, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37473480

RESUMO

DNA topoisomerase I (TOP1) catalytic inhibitors are a promising class of antitumor agents. Oleanolic acid derivatives are potential TOP1 catalytic inhibitors. However, their inhibitory activity still needs to be enhanced, and the stability and hotspot residue sites of their interaction with TOP1 remain to be elucidated. Herein, a novel oleanolic acid derivative, OA4 (N-(3-(methyl(3-(orotic amido)propyl)amino)propyl)oleanolamide), was identified by rational design. Subsequently, molecular dynamics simulations were performed to explore the stability and conformational dynamics of the TOP1-OA4 complex. The molecular mechanics/generalized Born surface area method calculated the binding free energy and predicted Arg488, Ile535, and His632 to be hotspot residues. Biological experiments verified that OA4 is a nonintercalative TOP1 catalytic inhibitor. OA4 exhibits better proliferation inhibitory activity against tumor cells than normal cells. Furthermore, OA4 can induce apoptosis and effectively suppress the proliferation and migration of cancer cells. This work provides new insights for the development of novel TOP1 catalytic inhibitors.


Assuntos
Antineoplásicos , Ácido Oleanólico , Inibidores da Topoisomerase I/química , Simulação de Dinâmica Molecular , DNA Topoisomerases Tipo I/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química
5.
Chem Biodivers ; 20(3): e202201176, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36746759

RESUMO

Leonurus japonicus Houtt. has been traditionally used to treat many ailments. This study evaluated the activating blood circulation, anti-inflammatory, and diuretic effects of L. japonicus extract (LJ) and identified its phytochemicals. In this work, the phytochemicals in LJ were identified using liquid chromatography mass spectrometry. Rats were randomly assigned to three groups (n=8): Control group was treated with saline, while the Model group (saline) and LJ group (426 mg/kg) had induced traumatic injury. All rats were treated with once by daily oral gavage for one week. The biochemical indices and protein expression were measured. Herein, 79 constituents were identified in LJ, which were effective in elevating body weight, food consumption, water intake, and urinary excretion volume, as well as in ameliorating traumatic muscle tissues in model rats. In addition, LJ prominently decreased the contents of plasma viscosity, platelet aggregation rate, thrombin time, prothrombin time, activated partial thromboplastin time, fibrinogen, thromboxane B2 (TXB2), TXB2/6-keto-prostaglandin F1α (6-keto-PGF1α), urokinase-type plasminogen activator (u-PA), plasminogen activator inhibitor 1 (PAI-1), PAI-1/tissue-type PA (t-PA), and PAI-1/u-PA, while significantly increasing antithrombin III, 6-keto-PGF1α, and t-PA contents. Furthermore, LJ notably inhibited tumor necrosis factor alpha, interleukin 6 (IL-6), IL-8, angiotensin II, antidiuretic hormone, aldosterone, aquaporin 1 (AQP1), AQP2, and AQP3 levels, and markedly elevating IL-10 and natriuretic peptide levels. Finally, LJ markedly reduced the protein expression of AQP1, AQP2, and AQP3 compared to the model group. Collectively, LJ possessed prominent activating blood circulation, anti-inflammatory, and diuretic effects, thus supporting the clinical application of L. japonicus.


Assuntos
Medicamentos de Ervas Chinesas , Hemostasia , Leonurus , Animais , Ratos , Anti-Inflamatórios , Aquaporina 2 , Diuréticos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Leonurus/química , Leonurus/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ratos Sprague-Dawley , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Hemostasia/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
6.
Front Endocrinol (Lausanne) ; 13: 1058651, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36726469

RESUMO

Asthenozoospermia is the most common cause of male infertility. Dynein protein arms play a crucial role in the motility of sperm flagella and defects in these proteins generally impair the axoneme structure and affect sperm flagella function. In this study, we performed whole exome sequencing for a cohort of 126 infertile patients with asthenozoospermia and identified homozygous DNALI1 mutation in one patient from a consanguineous family. This identified homozygous mutation was verified by Sanger sequencing. In silico analysis showed that this homozygous mutation is very rare, highly pathogenic, and very conserved. Sperm routine analysis confirmed that the motility of the spermatozoa from the patient significantly decreased. Further sperm morphology analysis showed that the spermatozoa from the patient exhibited multiple flagella morphological defects and a specific loss in the inner dynein arms. Fortunately, the patient was able to have his child via intracytoplasmic sperm injection treatment. Our study is the first to demonstrate that homozygous DNALI1 mutation may impair the integration of axoneme structure, affect sperm motility and cause asthenoteratozoospermia in human beings.


Assuntos
Astenozoospermia , Dineínas , Humanos , Masculino , Astenozoospermia/genética , Axonema/genética , Axonema/patologia , Dineínas/genética , Mutação , Sêmen , Motilidade dos Espermatozoides/genética
7.
Biol Pharm Bull ; 44(7): 926-931, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33952795

RESUMO

Background Astragalus polysaccharide (APS) had shown great promise in anti-tumour activities in our previous studies. The present study was designed to investigate whether APS has synergistic effect with cisplatin on the growth-inhibitory of human nasopharyngeal carcinoma cell lines and the possible mechanism. Methods Here, nasopharyngeal carcinoma cell lines (CNE-1) were divided into CNE-1 group, Cisplatin treatment group (2 µg/mL Cisplatin), APS treatment group (200 µg/mL APS) and combination group (2 µg/mL Cisplatin and 200 µg/mL APS). The proliferation inhibition rate of CNE-1 cells was determined by Cell Counting Kit-8 (CCK-8) method after treatment with different concentrations of APS for 24, 48, and 72 h. Apoptosis rates and cell cycle retardation of cells were detected by flow cytometry. Cell migration and invasion was evaluated by transwell assay. Western blotting and quantitative (q)RT-PCR were performed to detect the expression of Bcl-2, Bax, caspase-3, matrix metalloproteinase-2 (MMP-2), p53 and matrix metalloproteinase-9 (MMP-9) proteins in CNE-1 cells. Results APS have an inhibition on the proliferation of CNE-1 cells with time and dose dependence manner. Both the APS and combination therapy could promote apoptosis of CNE-1 cells, with the count of cells increased in G0/G1 and S phase while decreased in G2/M phase, and inhibited the migration and invasion of CNE-1 cells. Moreover, co-administration of Cisplatin and APS was more efficacious for the antitumor effect than either agent alone, as evidenced by the significant decrease in MMP-9 level and increase in p53. Conclusion APS, in combination with cisplatin, had significantly synergistic growth-inhibitory effect on nasopharyngeal carcinoma cell lines, which may be related to cell cycle and migration induction.


Assuntos
Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cisplatino/farmacologia , Carcinoma Nasofaríngeo/tratamento farmacológico , Polissacarídeos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
Curr Med Sci ; 38(6): 1032-1037, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30536066

RESUMO

The risk factors associated with strangulated ovarian hernia (SOH) in female patients (<1 year old) were identified. A retrospective analysis was conducted regarding the data from 2006 to 2017. The patients were divided into 2 groups: SOH group (n=9) and non-SOH group (n=23). Patient demographics, clinical signs, preoperative examinations and intraoperative findings were compared between the two groups, and risk factors for SOH were tested using a binary logistic regression model. To explore whether greater ovary was more likely to be twisted, leading to SOH, all the patients were divided into ovary volume <5 cm3 and ≥5 cm3 groups and the association between ovarian volume and ovary torsion was assessed. Among a total of 32 female patients (<1 year old) with incarcerated ovarian herniation, 9 patients developed SOH. The single variate analysis revealed that times of manual reduction, ovarian volume, ovary with or without multiple cysts, ovary torsion or not and angle of ovary torsion were found to be significant factors associated with SOH. The multivariate analysis showed ovarian volume was evidenced as an independent risk factor for SOH. Furthermore, the incidence of ovary torsion was significantly higher in ovarian volume ≥5 cm3 group than in ovarian volume <5 cm3 group, indicating that larger ovary was more likely to result in ovary torsion, leading to SOH. Our study demonstrated that the odds of SOH increased with increasing ovarian volume in female patients (<1 year old) because the relatively greater ovary at this age was more likely to be incarcerated and twisted, leading to SOH.


Assuntos
Hérnia Inguinal/patologia , Tamanho do Órgão/fisiologia , Doenças Ovarianas/patologia , Ovário/patologia , Anormalidade Torcional/patologia , Feminino , Humanos , Lactente , Estudos Retrospectivos , Fatores de Risco
9.
Drug Deliv ; 23(4): 1282-90, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25417833

RESUMO

The purpose of this study is to synthesize a novel galactosylated cholesterol derivative, cholesterol-diethenyl decanedioate-lactitol (CHS-DD-LA) through lipase-catalyzed esterification in non-aqueous and to evaluate the preparation, pharmacokinetics and biodistribution of docetaxel (DOC) liposomes modified with CHS-DD-LA (G-DOC-L), which may actively gather at the liver compared with the conventional DOC liposomes (DOC-L) and commercial dosage form of DOC injection (DOC-i). A rapid and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed for the determination of the DOC concentration in plasma and tissues with Taxol as the internal standard (IS). To measure the liver-targeting effect of the G-DOC-L, relative uptake rate (Re), peak concentration ratio (Ce), targeting efficiency (Te) and relative targeting efficiency (RTe) were reduced as the evaluation parameters. The results showed that the entrapment efficiency, particle size and Zeta potential of G-DOC-L was 76.8 ± 3.5%, 95.6 nm and 27.19 mV, respectively. After i.v. administration at the dose of 2.5 mg/kg in rats, a decrease in the AUC, MRT and an increase in CL (p < 0.05) were observed in the G-DOC-L group compared with DOC-L. All these results suggested that galactose-anchored liposomes could rapidly be removed from the circulation in vivo. The tissue distribution of G-DOC-L was widely different from that of DOC-L. The Re of G-DOC-L, DOC-L on liver was 4.011, 0.102; Ce was 3.391, 0.111; Te was 55.01, 3.08, respectively, demonstrating that G-DOC-L had an excellent effect on liver-targeting, which may help to improve the therapeutic effect of hepatic diseases.


Assuntos
Colesterol/química , Lipase/metabolismo , Fígado/efeitos dos fármacos , Taxoides/farmacocinética , Animais , Catálise , Linhagem Celular Tumoral , Docetaxel , Sistemas de Liberação de Medicamentos , Esterificação , Lipase/química , Lipase/farmacocinética , Lipossomos , Fígado/química , Ratos , Espectrometria de Massas em Tandem , Taxoides/metabolismo
10.
Biopolymers ; 101(3): 272-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23828220

RESUMO

A novel heptapeptide comprising Ile-Gln-Ser-Pro-His-Phe-Phe (IQSPHFF) identified and found to undergo self-assembly into microparticles in solution. To understand the effects of ultraviolet (UV) irradiation on the self-assembly process, IQSPHFF solutions were exposed to the UV light of 365 nm at room temperature. This exposure was found to have a profound effect on the morphology of the self-assembled aggregates, converting the microparticles to nanorod shapes. Circular dichroism and FTIR studies indicated distinct structural differences in the arrangements of the peptide moieties before and after UV irradiation. However, Mass spectrum analysis and high performance liquid chromatography of the peptide molecules before and after UV irradiation demonstrated that the chemical structure of IQSPHFF was not changed. UV-visible spectroscopy and fluorescence spectroscopy studies showed that the absorption peak both increased after UV irradiation. Overall, our data show that the heptapeptide with UV-responsive properties.


Assuntos
Dicroísmo Circular , Peptídeos , Peptídeos/química , Soluções , Espectrometria de Fluorescência , Raios Ultravioleta
11.
Vet Parasitol ; 196(1-2): 179-83, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23523013

RESUMO

To analyse genetic variability and population structure, 84 isolates of Echinococcus granulosus (Cestoda: Taeniidae) collected from various host species at different sites of the Tibetan plateau in China were sequenced for the whole mitochondrial nad1 (894 bp) and atp6 (513 bp) genes. The vast majority were classified as G1 genotype (n=82), and two samples from human patients in Sichuan province were identified as G3 genotype. Based on the concatenated sequences of nad1+atp6, 28 different haplotypes (NA1-NA28) were identified. A parsimonious network of the concatenated sequence haplotypes showed star-like features in the overall population, with NA1 as the major haplotype in the population networks. By AMOVA it was shown that variation of E. granulosus within the overall population was the main pattern of the total genetic variability. Neutrality indexes of the concatenated sequence (nad1+atp6) were computed by Tajima's D and Fu's Fs tests and showed high negative values for E. granulosus, indicating significant deviations from neutrality. FST and Nm values suggested that the populations were not genetically differentiated.


Assuntos
DNA Mitocondrial/genética , Equinococose/veterinária , Echinococcus granulosus/genética , Variação Genética , Altitude , Animais , Demografia , Equinococose/epidemiologia , Equinococose/parasitologia , Echinococcus granulosus/fisiologia , Haplótipos , Humanos , Tibet/epidemiologia
12.
Korean J Parasitol ; 49(2): 145-51, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21738270

RESUMO

The comparative efficacy of 2 anthelmintics (ivermectin and levamisole) against Baylisascaris transfuga migrating and encapsulated larvae was studied in mice. A total of 60 BALB/c mice inoculated each with about 1,000 embryonated B. transfuga eggs were equally divided into 6 groups (A-F) randomly. Mice of groups A and B were treated with ivermectin and levamisole, respectively, on day 3 post-infection (PI). Mice of groups A-C were killed on day 13 PI. Similarly, groups D and E were treated with ivermectin and levamisole, respectively, on day 14 PI, and all mice of groups D-F were treated on day 24 PI. The groups C and F were controls. Microexamination was conducted to count the larvae recovering from each mouse. The percentages of reduction in the number of migrating larvae recovered from group A (ivermectin) and B (levamisole) were 88.3% and 81.1%, respectively. In addition, the reduction in encapsulated larvae counts achieved by ivermectin (group D) and levamisole (group E) was 75.0% and 49.2%, respectively. The results suggested that, to a certain extent, both anthelmintics appeared to be more effective against migrating larvae than encapsulated larvae. However, in the incipient stage of infection, ivermectin may be more competent than levamisole as a larvicidal drug for B. transfuga.


Assuntos
Anti-Helmínticos/administração & dosagem , Infecções por Ascaridida/tratamento farmacológico , Ascaridoidea/efeitos dos fármacos , Ivermectina/administração & dosagem , Levamisol/administração & dosagem , Animais , Infecções por Ascaridida/parasitologia , Modelos Animais de Doenças , Feminino , Larva/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Doenças dos Roedores/tratamento farmacológico , Doenças dos Roedores/parasitologia , Resultado do Tratamento
13.
Lab Invest ; 90(7): 997-1003, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20386537

RESUMO

Upregulation of transforming growth factor-beta (TGF-beta) signaling is interrelated with the development of airway remodeling. In this study, we examined the role of two E3 ubiquitin ligases, Arkadia and Smurf2, which are critically required for TGF-beta signaling in airway remodeling. Rats were immunized with ovalbumin (OVA) and then challenged with an OVA aerosol. In in vitro experiments, normal human bronchial epithelial cells were stimulated with TGF-beta(1) with or without the preincubation of Arkadia/Smurf2 small interfering RNA (siRNA) or lactacystin (an inhibitor of proteasomal degradation). In the lungs of OVA-treated rats, a large number of inflammatory cells were present near the airways. An increased subepithelial collagen deposition was associated with high expression levels of Smad7, SnoN and Ski mRNAs, Arkadia, Smurf2, and TGF-beta type I receptor (TbetaRI), but low expression levels of Smad7, SnoN and Ski proteins. Smad7, SnoN and Ski interacted with both Arkadia and Smurf2 while TbetaRI only interacted with Smurf2 but not with Arkadia. In in vitro experiments, the inhibitory effect of TGF-beta(1) on the expression of Smad7, SnoN and Ski was reversed by Arkadia siRNA and lactacystin, whereas the stimulatory effect of TGF-beta(1) on the expression of TbetaRI protein and Smad7/SnoN/Ski mRNAs was not affected. In contrast, Smurf2 siRNA did not influence the effects of TGF-beta(1) on the expression of the above proteins. Our results suggest that Arkadia may contribute to the pathogenesis of airway remodeling through enhancing TGF-beta signaling by inducing the reduction of Smad7, SnoN and Ski proteins in OVA-sensitized and -challenged rats.


Assuntos
Asma/metabolismo , Pulmão/patologia , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Asma/etiologia , Asma/patologia , Células Cultivadas , Células Epiteliais/metabolismo , Humanos , Masculino , Proteínas do Tecido Nervoso/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteína Smad7/metabolismo , Fatores de Transcrição/metabolismo
14.
Protein J ; 28(3-4): 182-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19507014

RESUMO

This investigation, in vitro, shows that ozagrel, an antithrombotic drug, inhibited both monophenolase and diphenolase activities of mushroom tyrosinase when L: -tyrosine and L: -DOPA were assayed spectrophotometrically, respectively. The IC(50) values, for monophenolase and diphenolase activities, were 1.35 and 3.45 mM, respectively. Ozagrel was estimated to be a reversible mixed-type inhibitor of diphenolase activity with the constants (K (S1), K (S2), K (i1), and K (i2)) determined to be 2.21, 3.89, 0.454, and 0.799 mM, repectively. Increasing ozagrel concentrations provoked longer lag periods as well as a concomitant decrease in the monophenolase activity. Inhibition experiment demonstrated that ozagrel bound the enzyme at a site distincted from the substrate active site, but it bound to either E (Enzyme) or ES (Enzyme-Substrate) complex.


Assuntos
Agaricales/enzimologia , Inibidores Enzimáticos/farmacologia , Metacrilatos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Agaricales/efeitos dos fármacos , Catecol Oxidase/antagonistas & inibidores , Catecol Oxidase/metabolismo , Concentração Inibidora 50 , Cinética , Levodopa/metabolismo , Modelos Lineares , Oxirredutases/antagonistas & inibidores , Oxirredutases/metabolismo , Tirosina/metabolismo
15.
Colloids Surf B Biointerfaces ; 69(1): 85-90, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19108995

RESUMO

Tamoxifen microcapsules and drug loaded medicated fabrics were investigated. The microcapsules were prepared using a complex coacervation procedure involving gelatin B and acacia gum. The morphology, particle size, drug loading capacity and in vitro release characteristics of the drug microcapsules were optimized for coating tamoxifen microcapsules onto the cotton fabrics. Infrared (IR) spectra and SEM were used to characterize the medicated fabrics and air permeability and laundering testing were undertaken to determine the efficiency and effectiveness of the system. Results showed that optimum condition for the microcapsules was at drug/polymer ratio 1:4, polymer concentration 3%, and rate of stirring 1000 rpm. In vitro release assays demonstrated that the tamoxifen was liberated over 10h after an initial bust rate period. SEM images illustrated that the tamoxifen microcapsules were spherical in shape and were also tightly fixed on to the cotton fabrics fast. These observations demonstrate that we have designed and fabricated a medicated system that potentially could be applied within a transdermal drug delivery system and so act in a system for the treatment of breast cancer.


Assuntos
Composição de Medicamentos/métodos , Gossypium/química , Tamoxifeno/química , Ar , Cápsulas/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Permeabilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
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