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1.
Sci Rep ; 11(1): 1347, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33446747

RESUMO

Iron deficiency anemia (IDA) is a common micronutrient deficiency among pregnant women with severe consequences including impaired immuno-inflammatory system, premature birth, fetal death etc. The present study aimed to investigate the effects of three iron supplements on IDA female rats and their offspring. The IDA female rat model was established with low iron diet and the rats were then mated. After pregnancy, rats were fed diets containing different iron supplements (iron polysaccharide complex, iron protein succinylate and ferrous sulfate) until their offspring were 42 days old. Pregnancy outcomes, haematological, iron metabolism, physical and neurological development indexes were determined. The results showed that all three iron supplements improved the levels of hematological parameters of both mother and offspring rats. After iron supplementation, serum iron, transferrin saturation and serum ferritin levels were increased compared with the IDA group. The level of ferritin light chain in the liver and spleen of both mother and offspring rats in iron supplemented groups was significantly higher than that of the IDA group. The average number of born alive per litter in the iron treatment groups was significantly higher than that in the IDA group. Iron supplements also improved the physical growth and neurobehavioral development of offspring rats. It was also found that iron supplementation improved the expression of ferritin light chain and the synaptic growth associated proteins in the brain and hippocampus. No significant difference was found in the efficacy of three iron supplements. These results suggest that pregnant and postpartum IDA affects pregnancy outcomes, offspring physical development and causes neural impairment. Sufficient iron supplementation can significantly improve IDA and its adverse effects on both mother and offspring.


Assuntos
Anemia Ferropriva , Compostos Ferrosos/farmacologia , Metaloproteínas/farmacologia , Complicações Hematológicas na Gravidez , Resultado da Gravidez , Succinatos/farmacologia , Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Animais , Feminino , Ferro/farmacologia , Gravidez , Complicações Hematológicas na Gravidez/sangue , Complicações Hematológicas na Gravidez/tratamento farmacológico , Ratos , Ratos Wistar
2.
J Nanobiotechnology ; 18(1): 48, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183823

RESUMO

BACKGROUND: Specific targeting ability and good cell penetration are two critical requirements of tumor-targeted delivery systems. In the present work, we developed a novel matrix metalloprotein-triggered, cell-penetrating, peptide-modified, star-shaped nanoparticle (NP) based on a functionalized copolymer (MePEG-Peptide-Tri-CL), with the peptide composed of GPLGIAG (matrix metalloprotein-triggered peptide for targeted delivery) and r9 (cell-penetrating peptide for penetration improvement) to enhance its biological specificity and therapeutic effect. RESULTS: Based on the in vitro release study, a sustained release profile was achieved for curcumin (Cur) release from the Cur-P-NPs at pH 7.4. Furthermore, the release rate of Cur was accelerated in the enzymatic reaction. MTT assay results indicated that the biocompatibility of polymer NPs (P-NPs) was inversely related to the NP concentration, while the efficiency toward tumor cell inhibition was positively related to the Cur-P-NP concentration. In addition, Cur-P-NPs showed higher fluorescence intensity than Cur-NPs in tumor cells, indicating improved penetration of tumor cells. An in vivo biodistribution study further demonstrated that Cur-P-NPs exhibited stronger targeting to A549 xenografts than to normal tissue. Furthermore, the strongest tumor growth inhibition (76.95%) was observed in Cur-P-NP-treated A549 tumor xenograft nude mice, with slight pulmonary toxicity. CONCLUSION: All results demonstrated that Cur-P-NP is a promising drug delivery system that possesses specific enzyme responsiveness for use in anti-tumor therapy.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Metaloproteínas/farmacologia , Nanopartículas/administração & dosagem , Animais , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/química , Curcumina/farmacologia , Portadores de Fármacos , Liberação Controlada de Fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Tamanho da Partícula , Polímeros/química , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Angew Chem Int Ed Engl ; 57(1): 287-291, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29144008

RESUMO

The breast cancer stem cell (CSC) and bulk breast cancer cell potency of a series of metallopeptides containing dichloro(1,10-phenanthroline)copper(II) and various organelle-targeting peptide sequences is reported. The mitochondria-targeting metallopeptide 1 exploits the higher mitochondrial load in breast CSCs over the corresponding non-CSCs and the vulnerability of breast CSCs to mitochondrial damage to potently and selectively kill breast CSCs. Strikingly, 1 reduces the formation and size of mammospheres to a greater extent than salinomycin, an established CSC-potent agent. Mechanistic studies show that 1 enters CSC mitochondria, induces mitochondrial dysfunction, generates reactive oxygen species (ROS), activates JNK and p38 pathways, and prompts apoptosis. To the best of our knowledge, 1 is the first metallopeptide to selectivity kill breast CSCs in vitro.


Assuntos
Neoplasias da Mama/patologia , Complexos de Coordenação/farmacologia , Metaloproteínas/farmacologia , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Peptídeos/farmacologia , Fenantrolinas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Concentração Inibidora 50 , MAP Quinase Quinase 4/metabolismo , Metaloproteínas/química , Piranos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Free Radic Res ; 49(10): 1259-1268, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26110460

RESUMO

BACKGROUND: The objective of the present study was to determine whether single administration of the antioxidant enzyme bovine superoxide dismutase (bSOD) after radiation therapy (RT) mitigates development of pulmonary toxicity in rats. METHODS: Female F344 rats (n = 60) were divided among six experimental groups: (1) RT, single dose of 21 Gy to the right hemithorax; (2) RT + 5 mg/kg bSOD; (3) RT + 15 mg/kg bSOD; (4) No RT; (5) sham RT + 5 mg/kg bSOD; and (6) sham RT + 15 mg/kg bSOD. A single subcutaneous injection of bSOD (5 or 15 mg/kg) was administered 24 h post-radiation. The effects of bSOD on radiation-induced lung injury were assessed by measurement of body weight, breathing frequency, and histopathological changes. Immunohistochemistry was used to evaluate oxidative stress (8-OHdG(+), NOX4(+), nitrotyrosine(+), and 4HNE(+) cells), macrophage activation (ED1(+)), and expression of profibrotic transforming growth factor-ß or TGF-ß in irradiated tissue. RESULTS: Radiation led to an increase in all the evaluated parameters. Treatment with 15 mg/kg bSOD significantly decreased levels of all the evaluated parameters including tissue damage and breathing frequency starting 6 weeks post-radiation. Animals treated with 5 mg/kg bSOD trended toward a suppression of radiation-induced lung damage but did not reach statistical significance. CONCLUSIONS: The single application of bSOD (15 mg/kg) ameliorates radiation-induced lung injury through suppression of reactive oxygen species/reactive nitrogen species or ROS/RNS-dependent tissue damage.


Assuntos
Antioxidantes/uso terapêutico , Pulmão/efeitos da radiação , Metaloproteínas/uso terapêutico , Lesões Experimentais por Radiação/prevenção & controle , Pneumonite por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Superóxido Dismutase/uso terapêutico , Animais , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/efeitos da radiação , Bovinos , Colágeno/análise , Feminino , Fibrose , Injeções Subcutâneas , Pulmão/química , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/efeitos da radiação , Metaloproteínas/administração & dosagem , Metaloproteínas/farmacologia , Pneumonite por Radiação/patologia , Protetores contra Radiação/administração & dosagem , Protetores contra Radiação/farmacologia , Ratos , Ratos Endogâmicos F344 , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Taxa Respiratória/efeitos dos fármacos , Taxa Respiratória/efeitos da radiação , Superóxido Dismutase/administração & dosagem , Superóxido Dismutase/farmacologia
5.
J Biol Inorg Chem ; 19(6): 839-51, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24557708

RESUMO

Conversion of prion protein (PrP) to an altered conformer, the scrapie PrP (PrP(Sc)), is a critical step in the development of transmissible spongiform encephalopathies. Both Cu(II) and nucleic acid molecules have been implicated in this conversion. Full-length PrP can bind up to six copper ions; four Cu(II) binding sites are located in the octarepeat domain (residues 60-91), and His-96 and His-111 coordinate two additional copper ions. Experimental evidence shows that PrP binds different molecules, resulting in diverse cellular signaling events. However, there is little information about the interaction of macromolecular ligands with Cu(II)-bound PrP. Both RNA and DNA sequences can bind PrP, and this interaction results in reciprocal conformational changes. Here, we investigated the interaction of Cu(II) and nucleic acids with amyloidogenic non-octarepeat PrP peptide models (comprising human PrP residues 106-126 and hamster PrP residues 109-149) that retain His-111 as the copper-anchoring residue. The effect of Cu(II) and DNA or RNA sequences in the aggregation, conformation, and toxicity of PrP domains was investigated at low and neutral pH. Circular dichroism and EPR spectroscopy data indicate that interaction of the PrP peptides with Cu(II) and DNA occurs at pH 7. This dual interaction induces conformational changes in the peptides, modulating their aggregation, and affecting the morphology of the aggregated species, resulting in different cytotoxic effects. These results provide new insights into the role of Cu(II) and nucleic acid sequences in the structural conversion and aggregation of PrP, which are both critical events related to prion pathogenesis.


Assuntos
Cobre/química , Metaloproteínas/farmacologia , Ácidos Nucleicos/química , Peptídeos/química , Príons/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Metaloproteínas/química , Camundongos , Relação Estrutura-Atividade
6.
Chemistry ; 19(39): 13017-29, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23934861

RESUMO

The synthesis and stereochemical assignment of two classes of iron-containing nucleoside analogues, both of which contain a butadiene-Fe(CO)3 substructure, is described. The first type of compounds are Fe(CO)3-complexed 3'-alkenyl-2',3'-dideoxy-2',3'-dehydro nucleosides (2,5-dihydrofuran derivatives), from which the second class of compounds is derived by formal replacement of the ring oxygen atom by a CH2 group (carbocyclic nucleoside analogues). These compounds were prepared in a stereoselective manner through the metal-assisted introduction of the nucleobase. Whilst the furanoid intermediates were prepared from carbohydrates (such as methyl-glucopyranoside), the carbocyclic compounds were obtained by using an intramolecular Pauson-Khand reaction. Stereochemical assignments based on NMR and CD spectroscopy were confirmed by X-ray structural analysis. Biological investigations revealed that several of the complexes exhibited pronounced apoptosis-inducing properties (through an unusual caspase 3-independent but ROS-dependent pathway). Furthermore, some structure-activity relationships were identified, also as a precondition for the design and synthesis of fluorescent and biotin-labeled conjugates.


Assuntos
Biotina/síntese química , Corantes Fluorescentes/síntese química , Ferro/química , Metaloproteínas/síntese química , Metaloproteínas/farmacologia , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Apoptose/efeitos dos fármacos , Biotina/química , Corantes Fluorescentes/química , Espectroscopia de Ressonância Magnética , Metaloproteínas/química , Estrutura Molecular , Nucleosídeos/química , Relação Estrutura-Atividade , Difração de Raios X
7.
Toxicon ; 60(3): 302-11, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22579637

RESUMO

As one of the major protein (enzyme) components of snake venom (SV), L-amino acid oxidase (LAAO) plays an important role in the toxicities and biological activities for SV. Accumulated researches in the past decade gradually revealed that SV-LAAOs induce platelet aggregation, cell apoptosis and cytotoxicity, and have anti-microbial, anti-leishmaniasis, anti-tumor and anti-HIV activity. Except for the enzymatic and structural characteristics of SV-LAAOs, the biological functions of SV-LAAOs and relevant action mechanisms are also summarized and discussed in the review. This work might provide useful inputs for future studies on SV-LAAOs.


Assuntos
Descoberta de Drogas , L-Aminoácido Oxidase/metabolismo , Proteínas de Répteis/metabolismo , Venenos de Serpentes/enzimologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Coagulantes/química , Coagulantes/metabolismo , Coagulantes/farmacologia , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicoproteínas/farmacologia , Humanos , L-Aminoácido Oxidase/química , L-Aminoácido Oxidase/farmacologia , Metaloproteínas/química , Metaloproteínas/metabolismo , Metaloproteínas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Conformação Proteica , Proteínas de Répteis/química , Proteínas de Répteis/farmacologia
8.
Clin Lymphoma Myeloma Leuk ; 11(6): 490-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21889435

RESUMO

INTRODUCTION: It was demonstrated that metallopanstimulin-1 (MPS-1, RPS27) inhibited the growth of tumors formed by head and neck squamous cell carcinoma cells and reduced paxillin gene expression. METHODS: The present study examined whether and how MPS-1 affects another type of cancer, multiple myeloma (CAG). Enhanced expression of MPS-1 dramatically inhibited CAG in vitro and in vivo. RESULTS: Overexpression of MPS-1 resulted in decreased fibroblast growth factor (FGF2) receptor 3 and impaired endogenous MAPK/ErK signaling. MAPK/ErK signaling was not stimulated by adding recombinant FGF2 to myeloma cells overexpressing MPS-1. CONCLUSIONS: These data suggest that MPS-1 suppresses CAG growth and that weakened FGF2 signaling may contribute to this effect.


Assuntos
Metaloproteínas/biossíntese , Mieloma Múltiplo/metabolismo , Proteínas Nucleares/biossíntese , Proteínas de Ligação a RNA/biossíntese , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Proteínas Ribossômicas/biossíntese , Animais , Apoptose/fisiologia , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Meios de Cultivo Condicionados , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Metaloproteínas/genética , Metaloproteínas/farmacologia , Camundongos , Camundongos Nus , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/farmacologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/farmacologia , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/biossíntese , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/farmacologia , Transdução de Sinais , Transfecção , Transplante Heterólogo
9.
J Pharm Pharmacol ; 57(2): 213-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15720785

RESUMO

The metalloantibiotic bacitracin is a known inhibitor of protein disulfide isomerase (PDI). The disulfide-linked interleukin-12 (IL-12) alphabeta-heterodimer and beta2-homodimer forms are crucial mediators of cell-mediated immune responses and inflammatory reactions. Bacitracin was found to potently block secretion of both the alphabeta- and beta2-dimer forms of IL-12, while it did not affect secretion of the beta-monomer. This inhibition coincided with a reduction in the intracellular amount of PDI found in complex with the beta-chain during intracellular transit. Bacitracin did not affect mRNA levels of the alphabeta- and beta-chain. Similar to bacitracin, N-acetylcysteine blocked alphabeta- and beta2-secretion as well as PDI-beta-chain complex formation. Thus, blocking PDI or shifting the endoplasmic reticulum towards a more reduced status disrupts the oxidative folding pathway or assembly of IL-12 dimer forms. The assembly stage of cytokines in the endoplasmic reticulum may represent a novel target for pharmacological intervention.


Assuntos
Bacitracina/farmacologia , Interleucina-12/antagonistas & inibidores , Interleucina-12/metabolismo , Acetilcisteína/farmacologia , Animais , Bacitracina/química , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/enzimologia , Humanos , Interleucina-12/genética , Metaloproteínas/química , Metaloproteínas/farmacologia , Isomerases de Dissulfetos de Proteínas/antagonistas & inibidores , Isomerases de Dissulfetos de Proteínas/fisiologia , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Kidney Int ; 64(6): 1968-77, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14633119

RESUMO

BACKGROUND: The ureteric buds and metanephric mesenchymal cells reciprocally induce each other's maturation during kidney development, and implicated transcription factors, secreted growth factors, and cell surface signaling peptides are critical regulators of renal branching morphogenesis. Protein kinase C (PKC) is a key enzyme in the signal transduction mechanisms in various biologic processes, including development, because it regulates growth and differentiation. Inhibition of PKC by the sphingolipid product ceramide interferes with nephron formation in the developing kidney, but the molecule that controls ureteric bud branching downstream of PKC is still unknown. METHODS: Differential display polymerase chain reaction (PCR) of metanephroi cultured with a PKC activator and inhibitor was performed. We also examined the role of a novel gene in kidney development with organ culture system. RESULTS: A novel gene encoding a 759 bp mRNA was identified, and we named it metanephros-derived tubulogenic factor (MTF)/L47. Inhibition of MTF with antisense oligonucleotide impaired ureteric bud branching by cultured metanephroi, and addition of recombinant MTF protein promoted ureteric bud branching in cultured metanephroi and increased cell proliferation. CONCLUSION: We identified a novel molecule in developing kidney that is capable of modulating ureteric bud branching and kidney differentiation.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Rim/embriologia , Proteínas de Membrana/genética , Metaloproteínas/genética , Proteínas de Neoplasias/genética , Proteínas Ribossômicas/genética , Ureter/embriologia , Envelhecimento/genética , Envelhecimento/metabolismo , Sequência de Aminoácidos , Animais , Apoptose , Divisão Celular/efeitos dos fármacos , Clonagem Molecular , Embrião de Mamíferos/citologia , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/fisiologia , Desenvolvimento Embrionário e Fetal/genética , Ativação Enzimática/fisiologia , Proteínas Ligadas por GPI , Rim/crescimento & desenvolvimento , Rim/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/farmacologia , Proteínas de Membrana/fisiologia , Metaloproteínas/metabolismo , Metaloproteínas/farmacologia , Metaloproteínas/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Dados de Sequência Molecular , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/farmacologia , Proteínas de Neoplasias/fisiologia , Técnicas de Cultura de Órgãos , Proteína Quinase C/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/farmacologia , Proteínas Ribossômicas/fisiologia , Distribuição Tecidual
11.
J Biochem ; 131(2): 233-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11820937

RESUMO

The apoptotic cell death of Jurkat cells due to Cd(2+) toxicity was studied by fluorescence microscopic observation and DNA fragmentation assaying. It was suggested that the apoptotic response to Cd(2+) was less clear than that to a typical apoptosis inducer, ultraviolet light (254 nm). Examination of MAP kinase phosphorylation (p38, JNKs, and c-Jun) due to Cd(2+) toxicity indicated that the phosphorylation was very slowly activated (4 h after stimulation), while UV light could activate the phosphorylation immediately. Therefore, it was suggested that Cd(2+) may not be a typical apoptosis inducer. Antioxidants [glutathione (GSH) and N-acetylcysteine (NAC)] could detoxify Cd(2+), indicating that the toxicity is a kind of oxidative stress. The detoxification effect of antioxidants showed cooperation with Bcl-2, suggesting that Cd(2+)-treatment causes diversified toxic signals including oxidative stress. On the addition of a plant-specific peptide, phytochelatin [PC(7), (gammaGlu-Cys)(7)-Gly], to the medium, the detoxification of Cd(2+) and cooperation with Bcl-2 were more intense than in the cases of GSH and NAC. Using an appropriate vector, a PC synthase gene was transferred from Arabidopsis thaliana to the Jurkat cell. The transfectant exhibited resistance to Cd(2+) and production of plant-specific PC (PC(2-6)).


Assuntos
Apoptose/efeitos dos fármacos , Cádmio/toxicidade , Quelantes/farmacologia , Células Jurkat/efeitos dos fármacos , Metaloproteínas/farmacologia , Acetilcisteína/metabolismo , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Aminoaciltransferases/farmacologia , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Quelantes/metabolismo , Primers do DNA/química , Resistência a Medicamentos , Sequestradores de Radicais Livres/metabolismo , Glutationa/metabolismo , Humanos , Inativação Metabólica , Proteínas Quinases JNK Ativadas por Mitógeno , MAP Quinase Quinase 4 , Metaloproteínas/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estresse Oxidativo , Fitoquelatinas , Plantas/química , Plasmídeos , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Fatores de Tempo , Transfecção , Proteínas Quinases p38 Ativadas por Mitógeno
12.
J Inorg Biochem ; 86(2-3): 595-602, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11566332

RESUMO

Phytochelatins (PCs, (gamma Glu-Cys)(n)-Gly, n=2-11) are produced by higher plants, algae and some fungi in order to detoxify Cd(2+) by sequestration to form Cd-PCs complexes. In order to investigate what chemical structures of PCs are responsible for their metal-binding ability, various cysteine-rich peptides ((X-Cys)(7)-Gly, X=Glu, Asp, Lys, Gly, Ser and Gln) were chemically synthesized. Water-solubility, metal-binding property, and detoxification effect toward Cd(2+) were analyzed and compared with those of (gamma EC)(7)G. (SC)(7)G and (QC)(7)G were insoluble at pH below 10, and (GC)(7)G was not soluble at any pH between 1 and 12, indicating that charged side chains were at least required for the molecules to be solubilized in aqueous solution. By spectroscopic analyses using DTNB method and UV method, we found that (EC)(7)G and (DC)(7)G had almost equivalent abilities of Cd(2+)-binding as PC ((gamma EC)(7)G), indicating that the distance between each thiol group was not a major factor for the binding to Cd(2+). (beta DC)(7)G and (KC)(7)G interacted to Cd(2+) with fourth coordination as in the case of other soluble PC-related peptides. However, compared to (gamma EC)(7)G, (beta DC)(7)G displayed a slightly weaker binding to Cd(2+), and (KC)(7)G showed a drastic decrease in binding ability. The affinities of PC-related peptides toward Cd(2+) were evaluated as below; (gamma EC)(7)G=(EC)(7)G=(DC)(7)G>(beta DC)(7)G>>(KC)(7)G=weak binding. The results of Cd(2+)-detoxification assays were consistent with the affinity between Cd(2+) and the peptides. We concluded that the structure consisting of thiol and carboxyl groups were essential for the formation of a tight Cd-peptides complex such as Cd-PCs.


Assuntos
Quelantes/metabolismo , Quelantes/farmacologia , Metaloproteínas/metabolismo , Metaloproteínas/farmacologia , Metais/metabolismo , Peptídeos/metabolismo , Peptídeos/farmacologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacologia , Cádmio/metabolismo , Quelantes/química , Poluentes Ambientais/metabolismo , Glutationa , Técnicas In Vitro , Inativação Metabólica , Metaloproteínas/química , Peptídeos/síntese química , Peptídeos/química , Fitoquelatinas , Proteínas de Plantas/química , Ligação Proteica , Solubilidade
13.
Biochem Biophys Res Commun ; 284(3): 704-6, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11396959

RESUMO

Degradation of bisphenol A (BPA), an endocrine-disrupting chemical, was studied with a purified laccase from the basidiomycete Trametes villosa. SDS--polyacrylamide gel electrophoresis of the purified laccase gave one single band with a mobility corresponding to MW 65 kDa. The absorption spectrum showed the characteristics of a blue copper protein with a maximum peak at 600 nm. HPLC analysis revealed that 2.2 micromol BPA were degraded by incubation with 1.5 units of the purified laccase in a total volume of 1.0 ml at pH 6.0 and 60 degrees C for 3 h. The enzyme reaction proceeded rapidly without requirement of mediators for the electron transfer. Isolation and identification of several reaction products are in progress, in which one product was identified as 4-isopropenylphenol by a gas chromatography--mass spectrophotometer.


Assuntos
Oxirredutases/farmacologia , Fenóis/metabolismo , Polyporales/enzimologia , Compostos Benzidrílicos , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/farmacologia , Lacase , Espectrometria de Massas , Metaloproteínas/isolamento & purificação , Metaloproteínas/farmacologia , Microespectrofotometria , Oxirredutases/isolamento & purificação
14.
Ann N Y Acad Sci ; 886: 58-66, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10667203

RESUMO

The growth of solid tumors has been shown to depend on neovascularization. By understanding the mechanisms that control the neovascular response, it may be possible to design therapeutic strategies to selectively prevent or halt pathologic vascular growth and restrain cancer progression. Thrombospondin-1 is an extracellular matrix protein that among several functions suppresses capillary growth in angiogenesis assays. We have demonstrated that within the context of the mammary gland TSP1 can modulate normal development of blood vessels. Expression of TSP1 in transgenic animals under the control of the MMTV promoter was associated with a 50-72% reduction in capillary growth. In addition, TSP1 reduced tumor size in transgenic overexpressors. The data suggest an important role for TSP1 in modulating vascular growth in both normal and pathologic tissues. The antiangiogenic region of TSP1 has been mapped to the type I (properdin) repeats. To identify novel proteins with such a domain, we have cloned two cDNAs (METH-1 and METH-2) which also have antiangiogenic properties. In addition to carboxyterminal thrombospondin-like domains they also contain metalloproteinase and disintegrin sequences. Expression of both proteins is broad but nonoverlapping. Recombinant fragments from these sequences have strong antiangiogenic potential in the CAM and cornea pocket assays. At the same molar ratio, METH-1 and METH-2 are about 20-fold more potent than TSP1. We predict that these proteins are likely endogenous modulators of vascular growth with relevant therapeutic potential in cancer and other disease states.


Assuntos
Inibidores da Angiogênese/farmacologia , Metaloproteínas/farmacologia , Trombospondinas/farmacologia , Sequência de Aminoácidos , Inibidores da Angiogênese/química , Animais , Animais Geneticamente Modificados , Metaloproteínas/química , Dados de Sequência Molecular , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/patologia , Homologia de Sequência de Aminoácidos , Trombospondinas/química
15.
Comp Biochem Physiol A Physiol ; 116(4): 369-77, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9125688

RESUMO

The present study investigated the ability of uteroferrin to modulate the myelosuppressive effects of 5-fluorouracil (5-FU) in young pigs (Sus scrofa). Pigs (28-35 days of age; n = 6 per treatment) were infused with equal amounts of 5-FU on days 0 and 1 of the experimental period (37.5 mg/kg cumulative dose). Uteroferrin (100 micrograms/kg in 0.9% NaCl) or control (equivalent volume of 0.9% NaCl) was administered to pigs as intramuscular injections twice daily (08:00 and 20:00 hr) on days 1 through 21. Peripheral blood cell number, composition and progenitor cells were determined over 28 days. Treatment of pigs with 5-FU resulted in a rapid dose-dependent (P < 0.05) leukocytopenia. Concurrent treatment of pigs with uteroferrin reduced (P < 0.05) the rate of 5-FU-induced leukocytopenia (44 vs 77 +/- 7% decline from baseline on day 3) and enhanced (P < 0.05), the recovery from 5-FU on days 10 and 12 postinfusion. The positive effect of uteroferrin on leukocytes resulted primarily from a protection and/or enhanced recovery of neutrophils and monocytes. In addition, uteroferrin attenuated (P < 0.05) the suppression of red blood cell numbers after 5-FU administration (6.9 vs 6.1 +/- 0.2 x 10(6) cells/microliter on day 3), an affect reflected in increased hematocrit and hemoglobin concentrations. The effects of uteroferrin appeared to result from enhancement of the proliferation and/or differentiation of primitive pluripotent stem cells resistant to 5-FU, as concurrent treatment of pigs with uteroferrin resulted in a protection and/or enhanced recovery (P < 0.05) of CFU-GEMM, CFU-GM and BFU-E progenitor cells in the peripheral blood. These results are the first to demonstrate that uteroferrin can reduce the myelosuppressive effects of 5-FU in the pig and suggest that uteroferrin has hematopoietic growth factor activity in vivo.


Assuntos
Antimetabólitos Antineoplásicos/toxicidade , Medula Óssea/efeitos dos fármacos , Fluoruracila/antagonistas & inibidores , Fluoruracila/toxicidade , Leucopenia/prevenção & controle , Metaloproteínas/farmacologia , Fosfatase Ácida , Animais , Células da Medula Óssea , Relação Dose-Resposta a Droga , Contagem de Eritrócitos/efeitos dos fármacos , Células Precursoras Eritroides/efeitos dos fármacos , Hematócrito , Células-Tronco Hematopoéticas/efeitos dos fármacos , Isoenzimas , Contagem de Leucócitos/efeitos dos fármacos , Leucopenia/induzido quimicamente , Masculino , Suínos , Fosfatase Ácida Resistente a Tartarato
16.
Comp Biochem Physiol B Biochem Mol Biol ; 118(3): 569-77, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9467870

RESUMO

The present study investigated the ability of uteroferrin and recombinant bovine granulocyte monocyte/macrophage-colony stimulating factor (rbGM-CSF) to modulate the myelosuppressive effects of 5-fluorouracil (5-FU) in young female pigs (Sus scrofa). Pigs (N = 3/treatment) were infused with 5-FU (32.5 mg/kg) on days 0 and 1 of the experimental period. Uteroferrin (100 micrograms/kg in 0.9% NaCl), rbGM-CSF (10 micrograms/kg in 0.9% NaCl), uteroferrin + rbGM-CSF (as above) or control (0.9% NaCl) were administered as intramuscular injections twice daily (0800 and 2000 hr). Peripheral blood cell number, composition, and progenitor cells were determined over 28 days. Treatment of pigs with 5-FU resulted in a rapid leukocytopenia and thrombocytopenia (nadirs on days 5 and 7, respectively) and a modest decrease (P < 0.05) in red blood cell (RBC) number (nadir on day 14). Although nor affecting RBC and thrombocytes, treatment of pigs with uteroferrin had an initial protective effect (P < 0.05) on the 5-FU-induced leukocytopenia (63 and 64 vs 48 and 39 +/- 6% of baseline on days 3 and 5, respectively). In contrast, rbGM-CSF enhanced (P < 0.05) the rate of the leukocytopenia and had only minor effects on thrombocyte numbers relative to controls. These effects appeared to be additive, as pigs treated with uteroferrin + rbGM-CSF had a reduced rate of leukocytopenia compared to pigs treated with rbGM-CSF alone. Uteroferrin + rbGM-CSF also attenuated (P < 0.05) the suppression and enhanced (P < 0.05) recovery of RBC and thrombocyte numbers following 5-FU treatment. In control pigs, a modest rebound leukocytosis (122 +/- 6% of baseline) and thrombocytosis (141 +/- 9% of baseline) was evident. Uteroferrin enhanced (P < 0.05) the rebound leukocytosis (135 +/- 6% of baseline), but attenuated (P < 0.05) the thrombocytosis. In contrast, rbGM-CSF enhanced (P < 0.05) the duration of the leukocytosis during the recovery phase, an effect augmented by the combination of uteroferrin + rbGM-CSF. In addition, treatment with uteroferrin + rbGM-CSF resulted in a sustained thrombocytosis (days 12 to 21). As indicated by changes in CFU-GM, BFU-E, and CFU-GEMM progenitor cells in peripheral blood, the effects of uteroferrin and rbGM-CSF appeared to reflect their ability to enhance the proliferation and/or differentiation of both similar and distinct hematopoietic progenitor cells.


Assuntos
Fluoruracila/efeitos adversos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Leucócitos/efeitos dos fármacos , Metaloproteínas/farmacologia , Fosfatase Ácida , Fatores Etários , Animais , Plaquetas/efeitos dos fármacos , Bovinos , Ensaio de Unidades Formadoras de Colônias , Contagem de Eritrócitos/efeitos dos fármacos , Feminino , Fluoruracila/farmacologia , Isoenzimas , Proteínas Recombinantes/farmacologia , Fosfatase Ácida Resistente a Tartarato
17.
Comp Biochem Physiol B Biochem Mol Biol ; 118(3): 579-86, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9467871

RESUMO

The present study investigated the effect of uteroferrin and recombinant bovine granulocyte-monocyte/macrophage colony stimulating factor (rbGM-CSF) on hematopoiesis in young female pigs. Uteroferrin (100 micrograms/kg in 0.9% NaCl), rbGM-CSF (10 micrograms/kg in 0.9% NaCl), uteroferrin + rbGM-CSF (as above), or control (0.9% NaCl) were administered as intramuscular injections twice daily (0800 and 2000 hr). Peripheral blood cell number, composition, and progenitor cells were determined over 28 days. Uteroferrin had minimal effects on white blood cell (WBC) number, while rbGM-CSF caused both a rapid (days 2-7; maximum 122 +/- 8% of baseline) and late (days 16-28; maximum 133 +/- 8% of baseline) increase in WBC. Combination treatment with uteroferrin + rbGM-CSF abolished the initial increase in WBC number,but resulted in a prolonged increase in WBC number (days 14-28) relative to control. The rbGM-CSF-induced increase in WBC number resulted from rapid increases (P < 0.05) in monocytes and neutrophils. The addition of uteroferrin + rbGM-CSF enhanced (P < 0.05) the initial increase in the monocyte population and augmented the neutrophilia. In addition, uteroferrin + rbGM-CSF resulted in a dramatic eosinophilia (days 2-28), which was not detected in either the uteroferrin or rbGM-CSF treatments. Although not substantially affected by uteroferrin alone, rbGM-CSF caused an increase (P < 0.05) in thrombocyte numbers from days 1 through 9 (maximum 133 +/- 11% of baseline), an effect augmented by cotreatment with uteroferrin. The ability of these cytokines to modulate blood cell number and composition appeared to result from their effects on hematopoietic progenitor cells. Treatment of pigs with uteroferrin increased (P < 0.05) CFU-GEMM, CFU-GM, and BFU-E progenitor cells in peripheral blood, while rbGM-CSF caused increases (P < 0.05) relative to control in CFU-GM and CFU-GEMM. These effects were additive, as uteroferrin + GM-CSF augmented the increases in CFU-GM, BFU-E, and CFU-GEMM. Collectively, these results indicate that uteroferrin and rbGM-CSF can modulate hematopoiesis in young pigs. These effects were both additive and, in the case of neutrophils and eosinophils, synergistic. Hence, the mechanism(s) by which uteroferrin and rbGM-CSF modulate hematopoiesis appear to be different.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Sistema Hematopoético/efeitos dos fármacos , Metaloproteínas/farmacologia , Fosfatase Ácida , Animais , Plaquetas/efeitos dos fármacos , Bovinos , Ensaio de Unidades Formadoras de Colônias , Contagem de Eritrócitos/efeitos dos fármacos , Feminino , Isoenzimas , Contagem de Leucócitos/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia , Fosfatase Ácida Resistente a Tartarato
18.
Biol Reprod ; 53(6): 1436-45, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8562701

RESUMO

Iron-containing proteins catalyze lipid peroxidation when combined with either H2O2 or ascorbic acid (ASC). Microsomal membranes were prepared from Day 13 endometrial and conceptus tissues (5 pigs) and from Day 30 endometrial, placental, fetal liver, and fetus minus fetal liver tissues (5 pigs). Microsomal membranes were subjected to the following in vitro treatments: 1) no treatment, 2) 50 microM ASC, 3) 100 microM uteroferrin (UF), 4) 50 microM ASC + 100 microM UF, 5) 50 microM ASC + 100 microM UF + 10 microM apotransferrin (transferrin with no iron bound; ATF), and 6) 50 microM ASC + 100 microM UF + 10 microM holotransferrin (transferrin saturated with iron; HTF). For treatments 7 through 10, membranes were preincubated (0 degrees C, 3 h) with either 7) no treatment, 8) 50 microM fetuin, 9) 50 microM holoretinol binding protein (holoRBP: retinol binding protein [HoloRBP] with retinol bound), or 10) 50 microM apoRBP (RBP with no retinol bound) followed by incubation with 50 microM ASC + 100 microM UF. Lipid peroxidation was measured in the samples as thiobarbituric acid reactive substances (TBARS). Endogenous TBARS were greater (p < 0.05) in Day 13 conceptus than in Day 13 endometrium and were highest (p < 0.05) on Day 30 in fetal liver. Combined ASC and UF caused a large increase (p < 0.05) in TBARS in all membranes except Day 30 placental membranes. Addition of ATF, but not HTF, decreased TBARS production in all membrane preparations. HoloRBP, but not fetuin or apoRBP, decreased (p < 0.05) TBARS production in all but Day 30 endometrial membranes. In other experiments, when combined with ASC, UF/UF-associated protein complex induced less (p < 0.01) lipid peroxidation in fetal liver microsomal membranes than did free UF. Catalase and superoxide dismutase had no effect on UF-induced lipid peroxidation in fetal liver membranes. These results indicate that 1) UF combined with ASC induces lipid peroxidation in Day 13 endometrial and conceptus and Day 30 endometrial, fetal liver, and fetus minus liver microsomal membranes, and 2) ATF, holoRBP, and the UF-associated proteins, but not catalase or superoxide dismutase, inhibit this reaction.


Assuntos
Apoproteínas/farmacologia , Endométrio/metabolismo , Feto/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Metaloproteínas/farmacologia , Proteínas de Ligação ao Retinol/farmacologia , Transferrina/farmacologia , Fosfatase Ácida , Animais , Ácido Ascórbico/farmacologia , Catalase/farmacologia , Endométrio/efeitos dos fármacos , Feminino , Feto/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Ferro/farmacologia , Isoenzimas , Microssomos/metabolismo , Microssomos/ultraestrutura , Gravidez , Superóxido Dismutase/farmacologia , Suínos , Fosfatase Ácida Resistente a Tartarato , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
J Biol Chem ; 268(10): 6896-902, 1993 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-8463220

RESUMO

Uteroferrin (Uf) is a purple acid phosphatase with a bi-iron center. It is the major secretory product of the porcine uterus under the influence of progesterone and supplies iron to the developing fetuses during pregnancy. Tartrate-resistant acid phosphatases (TRAP) are clearly similar to Uf in many of their properties but are generally located intracellularly in lysosomes. To determine whether Uf and intracellular TRAP are distinct gene products, cDNA for the TRAP from pig spleen were compared with Uf cDNA. Although no full-length cDNA for the former were isolated, a TRAP cDNA of 1.1 kilobases was identical in nucleotide sequence to a Uf cDNA (1.42 kilobases) in the region of overlap, which included the entire 3'-end of the transcript and most of the open reading frame. TRAP purified from porcine spleen also had an NH2-terminal amino acid sequence that corresponded to that of Uf purified from uterine secretions and was also similar in sequence to intracellular TRAP isolated from tissues of other species, including ones from human osteoclastomas and spleen. Finally, Southern hybridization analysis with two probes specific for exons 1 and 2 of the Uf gene strongly suggested the presence of only a single gene for acid phosphatases of this class in the pig. A similar analysis performed on human DNA with an exon-specific probe for human TRAP was also consistent with a single gene. It is concluded that the difference in trafficking between a secreted TRAP, such as Uf, and TRAP located in lysosomes is not the result of distinctive primary sequence of the polypeptides and that the variability within species ascribed to such enzymes is most likely the result of minor posttranslational changes.


Assuntos
Fosfatase Ácida/genética , Metaloproteínas/farmacologia , Tartaratos/farmacologia , Fosfatase Ácida/efeitos dos fármacos , Fosfatase Ácida/isolamento & purificação , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA , Éxons , Feminino , Humanos , Isoenzimas , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Baço/enzimologia , Suínos , Fosfatase Ácida Resistente a Tartarato , Útero/enzimologia
20.
Exp Hematol ; 19(9): 910-5, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1893968

RESUMO

Uteroferrin is a purple progesterone-induced glycoprotein containing two molecules of iron per 35,000 molecular weight polypeptide, which has high amino acid sequence homology with Type 5 acid phosphatases from normal human placentae, from sera of patients with hairy cell leukemia, Gaucher's disease, and osteoporosis, as well as from normal spleens of pigs, cattle, rats, and mice. Results of the present study indicate that uteroferrin also has colony-forming unit (CFU) activity for committed erythroid (BFU-E) and granulocyte-monocyte/macrophage (CFU-GM) cell lines and exists as far back as the granulocyte, erythrocyte, monocyte/macrophage, megakaryocyte (CFU-GEMM) committed lineage. Uteroferrin exerts maximum CFU activities at 1 microgram/ml in serum-free culture medium with no supplemental iron (90 micrograms/ml ferric iron). However, when ferric iron concentration in medium was increased to 200 micrograms/ml, uteroferrin had maximum CFU activities at 100 pg/ml. Preincubation of uteroferrin with polyclonal antiserum or monoclonal antibody to uteroferrin effectively eliminated its CFU activities. Uteroferrin derived from human term placentae also exhibits BFU-E, CFU-GM, and CFU-GEMM activities. The mechanism by which uteroferrin stimulates proliferation and differentiation of primitive hematopoietic stem cells is unclear.


Assuntos
Ensaio de Unidades Formadoras de Colônias , Metaloproteínas/farmacologia , Fosfatase Ácida , Animais , Células Precursoras Eritroides , Feminino , Granulócitos , Humanos , Ferro/farmacologia , Isoenzimas , Macrófagos , Megacariócitos , Metaloproteínas/isolamento & purificação , Monócitos , Placenta/química , Suínos , Fosfatase Ácida Resistente a Tartarato
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