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1.
Am J Pathol ; 194(1): 30-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37827216

RESUMO

Benign prostate hyperplasia (BPH) is caused by the nonmalignant enlargement of the transition zone of the prostate gland, leading to lower urinary tract symptoms. Although current medical treatments are unsatisfactory in many patients, the limited understanding of the mechanisms driving disease progression prevents the development of alternative therapeutic strategies. The probasin-prolactin (Pb-PRL) transgenic mouse recapitulates many histopathological features of human BPH. Herein, these alterations parallel urodynamic disturbance reminiscent of lower urinary tract symptoms. Single-cell RNA-sequencing analysis of Pb-PRL mouse prostates revealed that their epithelium mainly includes low-androgen signaling cell populations analogous to Club/Hillock cells enriched in the aged human prostate. These intermediate cells are predicted to result from the reprogramming of androgen-dependent luminal cells. Pb-PRL mouse prostates exhibited increased vulnerability to oxidative stress due to reduction of antioxidant enzyme expression. One-month treatment of Pb-PRL mice with anethole trithione (ATT), a specific inhibitor of mitochondrial ROS production, reduced prostate weight and voiding frequency. In human BPH-1 epithelial cells, ATT decreased mitochondrial metabolism, cell proliferation, and stemness features. ATT prevented the growth of organoids generated by sorted Pb-PRL basal and LSCmed cells, the two major BPH-associated, androgen-independent epithelial cell compartments. Taken together, these results support cell plasticity as a driver of BPH progression and therapeutic resistance to androgen signaling inhibition, and identify antioxidant therapy as a promising treatment of BPH.


Assuntos
Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Masculino , Humanos , Camundongos , Animais , Idoso , Androgênios/farmacologia , Androgênios/metabolismo , Próstata/patologia , Hiperplasia Prostática/metabolismo , Antioxidantes/farmacologia , Plasticidade Celular , Hiperplasia/patologia , Chumbo/metabolismo , Chumbo/uso terapêutico , Camundongos Transgênicos , Prolactina/metabolismo , Prolactina/uso terapêutico , Células Epiteliais/metabolismo , Sintomas do Trato Urinário Inferior/metabolismo , Sintomas do Trato Urinário Inferior/patologia
2.
Future Med Chem ; 15(24): 2239-2255, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38014535

RESUMO

Background: Paracoccidioidomycosis (PCM) is a systemic infection caused by Paracoccidioides spp. (Pb). PCM can be associated or clinically confused with tuberculosis (TB), another pulmonary infection, caused by Mycobacterium tuberculosis (Mtb). Futhermore, the long treatment time of TB and PCM and the cases of TB drug resistance impose difficulties for the cure of these diseases. Results: New 1,3,4-oxadiazoles containing the 4-methoxynaphthalene ring were synthesized and their antimicrobial activity was evaluated against Pb and Mtb. The derivative 6n (with 2-hydroxy-5-nitrophenyl subunit) is the most promising of the series. Conclusion: The 1,3,4-oxadiazole 6n can be used as a prototype drug candidate, with anti-Pb and anti-MTb activities, showing a broad-spectrum profile for the treatment of both pulmonary infections.


Assuntos
Anti-Infecciosos , Mycobacterium tuberculosis , Paracoccidioidomicose , Tuberculose , Humanos , Oxidiazóis/farmacologia , Chumbo/uso terapêutico , Tuberculose/tratamento farmacológico , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/microbiologia , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico
3.
Mol Omics ; 19(5): 404-417, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-36938944

RESUMO

Abemaciclib (Ab) and palbociclib (Pb) are CDK4/6 inhibitors used to cure advanced breast cancer (BC). However, acquired resistance is a major challenge. The molecular mechanisms and signature proteins of therapy resistance for Ab and Pb drugs need to be explored. Here we developed resistant cells for Ab and Pb drugs in MCF-7 cell lines and explored the mechanisms and signature proteins of therapy resistance in BC. Proteome profiling was performed using the label-free proteome-orbitrap-fusion-MS-MS technique. Gene ontology (GO)-terms, KEGG pathways and network analysis were performed for the proteome data. Drug-resistant cells showed increased drug tolerance, enhanced colony formation potential and an increased gap-healing tendency for the respective drug. Up-regulation of survival genes (BCL-2 and MCL-1) and down-regulation of apoptosis inducers were observed. Drug-resistance markers (MDR-1 and ABCG2 (BCRP)) along with ESR-1, CDK4, CDK6, and cyclin-D1 genes were up-regulated in resistant cells. A total of 237 and 239 proteins were found to be differentially expressed in the Ab and Pb-resistant cells, respectively. Down-regulated proteins induce apoptosis signalling and nucleotide metabolisms and restrict EGFR signalling; however, up-regulated proteins induce Erk, wnt-ß-catenin, VEGFR-PI3K-AKT, glucose transportation, and hypoxia signalling pathways and regulate hydrogen peroxide signalling pathways. The panel of identified proteins associated with these pathways might have characteristics of molecular signature and new drug targets for overcoming drug resistance in breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Proteoma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/uso terapêutico , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Chumbo/metabolismo , Chumbo/uso terapêutico , Proteínas de Neoplasias/genética , Células MCF-7 , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/uso terapêutico
4.
J Med Chem ; 65(18): 12292-12318, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36084304

RESUMO

Drug development efforts that focused on single targets failed to provide effective treatment for Alzheimer's disease (AD). Therefore, we designed cholinesterase inhibition (ChEI)-based multi-target-directed ligands (MTDLs) to simultaneously target AD-related receptors. We built a library of 70 compounds, sequentially screened for ChEI, and determined σ1R, σ2R, NMDAR-GluN2B binding affinities, and P2X7R antagonistic activities. Nine fulfilled in silico drug-likeness criteria and did not display toxicity in three cell lines. Seven displayed cytoprotective activity in two stress-induced cellular models. Compared to donepezil, six showed equal/better synaptic protection in a zebrafish model of acute amyloidosis-induced synaptic degeneration. Two P2X7R antagonists alleviated the activation state of microglia in vivo. Permeability studies were performed, and four did not inhibit CYP450 3A4, 2D6, and 2C9. Therefore, four ChEI-based lead MTDLs are promising drug candidates for synaptic integrity protection and could serve as disease-modifying AD treatment. Our study also proposes zebrafish as a useful preclinical tool for drug discovery and development.


Assuntos
Doença de Alzheimer , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/uso terapêutico , Colinesterases , Donepezila/uso terapêutico , Chumbo/uso terapêutico , Ligantes , Peixe-Zebra/metabolismo
5.
Mol Omics ; 18(8): 716-730, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-35960011

RESUMO

BACKGROUND: cerebral malaria (CM) is an important complication of malaria with a high mortality rate. Artesunate is recommended as the first-line artemisinin compound treatment for severe malaria. Due to the difficulty of obtaining brain tissue samples clinically, the use of animals to research host responses to CM parasite infections is necessary. Rodent malaria models allow for detailed time series studies of host responses in multiple organs. To date, studies on the transcriptome of severe malaria are only limited to the parasites in the peripheral blood of patients, and there is little data on the transcriptional changes in brain tissue in mice with CM treated with artesunate. METHOD AND RESULT: in this study, fresh tissue samples (three biological replicates per mouse) from the same area of the brain in each animal were collected from the uninfected, Plasmodium berghei ANKA-infected and artesunate-treated C57BL/6 mice, and then transcriptome research was performed by the RNA-seq technique. Differentially expressed genes (DEGs) included Il-21, Tnf, Il-6, Il-1ß, Il-10, Ifng, and Icam-1. Among which, Il-6, Il-10, Tnf-α and Il-1ß were further verified and validated via qRT-PCR and ELISA. This revealed that Il-1ß (p < 0.0001), Il-10 (p < 0.05) and Tnf-α (p < 0.05) were significantly up-regulated in the Pb ANKA-infected versus uninfected group, while Il-1ß (p < 0.0001) and Tnf-α (p < 0.05) were significantly down-regulated after artesunate treatment. All DEGs were closely related to the top 3 artesunate treatment pathways, including the JAK-STAT signaling pathway, apoptosis, and Toll-like receptor signaling pathway. CONCLUSION: the mechanism of improving the prognosis of cerebral malaria by artesunate may not only involve the killing of plasmodium but also the inhibition of a cytokine storm in the host. This study provides new insights into the molecular mechanism by which artesunate improves the prognosis of cerebral malaria.


Assuntos
Antimaláricos , Artemisininas , Malária Cerebral , Animais , Anti-Inflamatórios/uso terapêutico , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Artesunato/farmacologia , Artesunato/uso terapêutico , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Molécula 1 de Adesão Intercelular/uso terapêutico , Interleucina-10/uso terapêutico , Interleucina-6/uso terapêutico , Chumbo/uso terapêutico , Malária Cerebral/tratamento farmacológico , Malária Cerebral/genética , Malária Cerebral/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , RNA-Seq , Receptores Toll-Like/uso terapêutico , Fator de Necrose Tumoral alfa/uso terapêutico
6.
Indian J Gastroenterol ; 41(2): 198-202, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35192187

RESUMO

In the last three decades, the use of herbal medications has been increasing for the treatment of various chronic disorders. Studies in the past have shown that many of these medicines could contain high levels of heavy metals, including lead. Therefore, we planned this study to evaluate the possibility of lead toxicity as the underlying cause in patients consuming these unnamed herbal medicines among patients presenting with significant abdominal pain. (Unexplained abdominal pain means pain in abdomen in which no etiology could be ascertained after all possible routine and specialized investigations including computerized axial tomography [CT] of the abdomen and upper gastrointestinal [UGI] endoscopy/colonoscopy). This is an observational case series of prospectively maintained data of all patients having unexplained abdominal pain and found to have an elevated blood lead level from 2011 to 2019. Lead toxicity was diagnosed when its blood lead level was >25 µg/dL. Total sixty-six patients with unexplained abdominal pain from 2011 to 2019 were recruited. Out of the sixty-six patients, seventeen had elevated blood lead levels. All seventeen patients had a history of ingestion of herbal medicines for more than 6 months. Among the seventeen patients, eight were taking it for infertility and sexual dysfunction, six for diabetes, two for arthritis and one for hypertension. Basophilic stippling was seen in one patient. Fourteen patients had low hemoglobin with a median value of 9.7 g/dL. Mean serum blood lead level was 87.1 µg/dL. None of them required anti-chelating agent. Lead toxicity owing to herbal medicine is not uncommon cause of unexplained abdominal pain. Most of these patients do not require a chelating agent for treatment. There is a need to bring these herbal medicines under strict regulations for displaying its constituents and their concentrations.


Assuntos
Intoxicação por Chumbo , Chumbo , Dor Abdominal/induzido quimicamente , Quelantes , Humanos , Chumbo/uso terapêutico , Intoxicação por Chumbo/diagnóstico , Intoxicação por Chumbo/tratamento farmacológico , Intoxicação por Chumbo/etiologia , Fitoterapia/efeitos adversos
7.
Br J Cancer ; 125(12): 1657-1665, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34671126

RESUMO

BACKGROUND: Despite therapeutic advances, Non-Hodgkin lymphoma (NHL) relapses can occur. The development of radioimmunotherapy (RIT) with α-emitters is an attractive alternative. In this study, we investigated the potential of α-RIT in conjunction with 212Pb-rituximab for the treatment of NHL. METHODS: EL4-hCD20-Luc cells (mouse lymphoma cell line) were used for in vitro and in vivo studies. Biodistribution and efficacy studies were performed on C57BL/6 mice injected intravenously with 25 × 103 cells. RESULTS: 212Pb-rituximab (0.925-7.4 kBq/mL) inhibit proliferation of EL4-hCD20-Luc cells in vitro. Biodistribution of 203/212Pb-rituximab in mice showed a significant tumour uptake and suggested that the liver, spleen, and kidneys were the organs at risk. For efficacy studies, mice were treated at either 11 days (early stage) or 20-30 days after injection of tumour cells (late stage). Treatment with 277.5 kBq 212Pb-rituximab significantly prolonged survival. Even at an advanced tumour stage, significant tumour regression occurred, with an increase in the median survival time to 28 days, compared with 9 days in the controls. CONCLUSIONS: These results show the efficacy of 212Pb-rituximab in a murine syngeneic lymphoma model, in terms of significant tumour regression and increased survival, thereby highlighting the potency of α-RIT for the treatment of NHL.


Assuntos
Antígenos CD20/metabolismo , Chumbo/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/radioterapia , Radioimunoterapia/métodos , Animais , Modelos Animais de Doenças , Humanos , Chumbo/farmacologia , Masculino , Camundongos
8.
BMC Gastroenterol ; 20(1): 263, 2020 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770948

RESUMO

BACKGROUND: Chronic exposure to lead causes lead to accumulate mainly in the liver. In vivo studies have shown that lead toxicity is related to alterations in the inflammatory response. We aimed to evaluate the association between lead poisoning and liver fibrosis as well as the change in the degree of liver fibrosis, levels of inflammatory mediators and glutathione (GSH) after chelation therapy. METHODS: Workers from a battery factory who were exposed to lead for > 12 months and had a blood lead level (BLL) > 70 µg/dL were enrolled (n = 86) in the study. Participants underwent chelation therapy with intravenous CaNa2EDTA for 2 days followed by treatment with oral D-penicillamine for 90 days. The primary outcome was the change in the degree of liver fibrosis, which was presented as liver stiffness (LS) measured by FibroScan®. Secondary outcomes were the changes in the levels of serum GSH and inflammatory mediators such as tumor necrosis factor-alpha (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) after chelation therapy. RESULTS: Among the 86 participants, there was a positive correlation between the duration of lead exposure and LS (r = 0.249, p = 0.021). To avoid the confounding effect of obesity-related steatosis, only 70 individuals who had controlled attenuation parameters < 296 dB/m, BMI < 25 kg/m2 and normal waist circumference were included in the interventional analysis. After chelation, the mean LS significantly decreased from 5.4 ± 0.9 to 4.8 ± 1.4 kPa (p = 0.001). Similarly, all of the inflammatory cytokines studied significantly decreased after chelation (p < 0.001); TNF-α decreased from 371.6 ± 211.3 to 215.8 ± 142.7; the levels of IL-1ß decreased from 29.8 ± 1.7 to 25.9 ± 4.3; and the levels of IL-6 decreased from 46.8 ± 10.2 to 35.0 ± 11.9. On the other hand, the mean GSH level increased significantly from 3.3 ± 3.3 to 13.1 ± 3.7 (p < 0.001) after chelation therapy. CONCLUSION: The duration of lead exposure was significantly correlated with the degree of liver fibrosis. Chelation treatment was associated with increased levels of GSH and decreased levels of proinflammatory cytokines and could potentially reduce the degree of LS. TRIAL REGISTRATION: This study was retrospectively registered and approved by the Thai Clinical Trial Registry (TCTR) on 2019-11-07. The TCTR identification number is TCTR20191108001 .


Assuntos
Intoxicação por Chumbo , Chumbo , Antioxidantes , Terapia por Quelação , Citocinas , Humanos , Chumbo/uso terapêutico , Intoxicação por Chumbo/complicações , Intoxicação por Chumbo/tratamento farmacológico , Fígado , Tailândia
9.
Mol Pharmacol ; 97(6): 409-422, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32241960

RESUMO

The microtubule-binding taxanes, docetaxel and cabazitaxel, are administered intravenously for the treatment of castration-resistant prostate cancer (CRPC) as the oral administration of these drugs is largely hampered by their low and highly variable bioavailabilities. Using a simple, rapid, and environmentally friendly microwave-assisted protocol, we have synthesized a number of 3,5-bis(styryl)pyrazoles 2a-l, thus allowing for their screening for antiproliferative activity in the androgen-independent PC3 prostate cancer cell line. Surprisingly, two of these structurally simple 3,5-bis(styryl)pyrazoles (2a and 2l) had concentrations which gave 50% of the maximal inhibition of cell proliferation (GI50) in the low micromolar range in the PC3 cell line and were thus selected for extensive further biologic evaluation (apoptosis and cell cycle analysis, and effects on tubulin and microtubules). Our findings from these studies show that 3,5-bis[(1E)-2(2,6-dichlorophenyl)ethenyl]-1H-pyrazole 2l 1) caused significant effects on the cell cycle in PC3 cells, with the vast majority of treated cells in the G2/M phase (89%); 2) induces cell death in PC3 cells even after the removal of the compound; 3) binds to tubulin [dissociation constant (Kd) 0.4 ± 0.1 µM] and inhibits tubulin polymerization in vitro; 4) had no effect upon the polymerization of the bacterial cell division protein FtsZ (a homolog of tubulin); 5) is competitive with paclitaxel for binding to tubulin but not with vinblastine, crocin, or colchicine; and 6) leads to microtubule depolymerization in PC3 cells. Taken together, these results suggest that 3,5-bis(styryl)pyrazoles warrant further investigation as lead compounds for the treatment of CRPC. SIGNIFICANCE STATEMENT: The taxanes are important components of prostate cancer chemotherapy regimens, but their oral administration is hampered by very low and highly variable oral bioavailabilities resulting from their poor absorption, poor solubility, high first-pass metabolism, and efficient efflux by P-glycoprotein. New chemical entities for the treatment of prostate cancer are thus required, and we report here the synthesis and investigation of the mechanism of action of some bis(styryl)pyrazoles, demonstrating their potential as lead compounds for the treatment of prostate cancer.


Assuntos
Antineoplásicos/uso terapêutico , Chumbo/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Pirazóis/uso terapêutico , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Sítios de Ligação , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Humanos , Chumbo/química , Masculino , Microtúbulos/efeitos dos fármacos , Modelos Moleculares , Células PC-3 , Pirazóis/síntese química , Pirazóis/química
10.
PLoS One ; 14(6): e0217757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216296

RESUMO

PURPOSE: Electron radiotherapy is a labor-intensive treatment option that is complicated by the need for field shaping blocks. These blocks are typically made from casting Cerrobend alloys containing lead and cadmium. This is a highly toxic process with limited precision. This work aims to provide streamlined and more precise electron radiotherapy by 3D using printing techniques. METHODS: The 3D printed electron cutout consists of plastic shells filled with 2 mm diameter tungsten ball bearings. Five clinical Cerrobend defined field were compared to the planned fields by measuring the light field edge when mounted in the electron applicator on a linear accelerator. The dose transmitted through the 3D printed and Cerrobend cutouts was measured using an IC profiler ion chamber array with 6 MeV and 16 MeV beams. Dose profiles from the treatment planning system were also compared to the measured dose profiles. Centering and full width half maximum (FWHM) metrics were taken directly from the profiler software. RESULTS: The transmission of a 16MeV beam through a 12 mm thick layer of tungsten ball bearings agreed within 1% of a 15 mm thick Cerrobend block (measured with an ion chamber array). The radiation fields shaped by ball bearing filled 3D printed cutout were centered within 0.4 mm of the planned outline, whereas the Cerrobend cutout fields had shift errors of 1-3 mm, and shape errors of 0.5-2 mm. The average shift of Cerrobend cutouts was 2.3 mm compared to the planned fields (n = 5). Beam penumbra of the 3D printed cutouts was found to be equivalent to the 15 mm thick Cerrobend cutout. The beam profiles agreed within 1.2% across the whole 30 cm profile widths. CONCLUSIONS: This study demonstrates that with a proper quality assurance procedure, 3D-printed cutouts can provide more accurate electron radiotherapy with reduced toxicity compared to traditional Cerrobend methods.


Assuntos
Neoplasias/radioterapia , Impressão Tridimensional , Tungstênio/uso terapêutico , Elétrons , Substâncias Perigosas/efeitos adversos , Substâncias Perigosas/uso terapêutico , Humanos , Chumbo/efeitos adversos , Chumbo/uso terapêutico , Método de Monte Carlo , Neoplasias/patologia , Aceleradores de Partículas , Cintilografia , Radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
12.
Dalton Trans ; 40(23): 6068-76, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21380408

RESUMO

Targeted α-particle therapy offers the potential for more specific tumor cell killing with less damage to surrounding normal tissue than ß-emitters because of the combination of short path length (50-80 µm) with the high linear energy transfer (100 keV µm(-1)) of this emission. These physical properties offer the real possibility of targeted (pre-targeted) α-therapy suitable for the elimination of minimal residual or micrometastatic disease. Targeted and pre-targeted radioimmunotherapy (RIT) using α-emitters such as (212)Bi (T(1/2) = 1.01 h) and (212)Pb (T(1/2) = 10.6 h) has demonstrated significant utility in both in vitro and in vivo model systems. (212)Pb, a promising α-particle emitting source, is the longer-lived parent nuclide of (212)Bi, and serves as an in vivo generator of (212)Bi. The radionuclide has been successfully used in RIT and pre-targeted RIT and demonstrated an enhanced therapeutic efficacy in combination with chemotherapeutics, such as gemcitabine and paclitaxel. The following perspective addresses the modes of radionuclide production, radiolabelling and chelation chemistry, as well as the application of (212)Pb to targeted and pre-targeted radiation therapy.


Assuntos
Chumbo/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Partículas alfa/uso terapêutico , Complexos de Coordenação/química , Complexos de Coordenação/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Compostos Heterocíclicos com 1 Anel/química , Humanos , Chumbo/química , Radioisótopos de Chumbo/química , Transferência Linear de Energia , Neoplasias/radioterapia , Radioimunoterapia , Tomografia Computadorizada de Emissão de Fóton Único
13.
Neurobiol Dis ; 37(3): 574-80, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19914377

RESUMO

Exposure to environmental lead (Pb) is a mild risk factor for amyotrophic lateral sclerosis (ALS), a paralytic disease characterized by progressive degeneration of motor neurons. However, recent evidence has paradoxically linked higher Pb levels in ALS patients with longer survival. We investigated the effects of low-level Pb exposure on survival of mice expressing the ALS-linked superoxide dismutase-1 G93A mutation (SOD1(G93A)). SOD1(G93A) mice exposed to Pb showed longer survival and increased expression of VEGF in the ventral horn associated with reduced astrocytosis. Pretreatment of cultured SOD1(G93A) astrocytes with low, non toxic Pb concentrations upregulated VEGF expression and significantly abrogated motor neuron loss in coculture, an effect prevented by neutralizing antibodies to VEGF. The actions of Pb on astrocytes might explain its paradoxical slowing of disease progression in SOD1(G93A) mice and the improved survival of ALS patients. Understanding how Pb stimulates astrocytic VEGF production and reduces neuroinflammation may yield a new therapeutic approach for treating ALS.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Astrócitos/efeitos dos fármacos , Chumbo/farmacologia , Medula Espinal/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Anticorpos Neutralizantes/farmacologia , Astrócitos/metabolismo , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Gliose/tratamento farmacológico , Gliose/etiologia , Gliose/fisiopatologia , Chumbo/uso terapêutico , Camundongos , Camundongos Transgênicos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Degeneração Neural/tratamento farmacológico , Degeneração Neural/etiologia , Degeneração Neural/fisiopatologia , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Medula Espinal/citologia , Medula Espinal/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase-1 , Taxa de Sobrevida , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
J Clin Periodontol ; 28(8): 776-81, 2001 Aug.
Artigo em Inglês, Francês, Alemão | MEDLINE | ID: mdl-11442738

RESUMO

BACKGROUND/AIM: Halitosis, mainly caused by bacteria located on the posterior dorsum of the tongue and in periodontal pockets, is due to formation of volatile sulfur compounds (VSC). The hypothesis to be tested was that the affinity of a metal for sulfur determines its anti-VSC activity. METHOD: Clinical tests were carried out on 12 subjects who rinsed with cysteine to induce halitosis (baseline) before rinsing with 7.34 mM ZnCl2, SnF2 and CuCl2. Mouth air VSC analyses were repeated following cysteine rinses at 1 h, 2 h and 3 h using a gas chromatograph. In vitro experiments tested toxic metals Hg2+, Pb2+ and Cd2+. 10-microl aliquots of metal salts were added to 1-ml aliquots of human whole saliva from 30 subjects. Samples were incubated overnight at 37oC and saliva headspace was analyzed for VSC in a gas chromatograph. CLINICAL RESULTS: Cu2+>Sn2+>Zn2+ (supports hypothesis). Zn2+ had significantly less anti-VSC effect compared with Cu2+ and Sn2+ at 1, 2 and 3 h. In vitro results indicated that Hg2+, Cu2+ and Cd2+ had close to 100% anti-VSC effect, and that Pb2+ was less effective and Cd2+ more effective than expected in inhibiting VSC. CONCLUSIONS: Apart from Hg2+ and Cu2+, the metals had a significantly greater effect on H2S than on CH3SH. Cu2+ and Hg2+ have well-known antibacterial activity and may presumably also operate by this mechanism.


Assuntos
Halitose/prevenção & controle , Sulfeto de Hidrogênio/análise , Metais/administração & dosagem , Antissépticos Bucais/administração & dosagem , Saliva/química , Compostos de Sulfidrila/análise , Adulto , Idoso , Análise de Variância , Testes Respiratórios , Cloreto de Cádmio/uso terapêutico , Cloretos/uso terapêutico , Cobre/uso terapêutico , Cisteína/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Halitose/induzido quimicamente , Humanos , Técnicas In Vitro , Chumbo/uso terapêutico , Masculino , Cloreto de Mercúrio/uso terapêutico , Metais/química , Pessoa de Meia-Idade , Saliva/efeitos dos fármacos , Compostos de Estanho/uso terapêutico , Resultado do Tratamento , Volatilização , Compostos de Zinco/uso terapêutico
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