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1.
Med Gas Res ; 8(3): 103-110, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30319765

RESUMO

Oxygen-ozone (O3) therapy serves as an alternative medical technique that increases the oxygen in the body along with the introduction of O3. O3 therapy has finally reached a level where the biological mechanisms of action have been understood, showing that they are in the domain of physiology, biochemistry, and pharmacology. Few clinical applications have been reviewed here as well as exemplifying that O3 therapy is particularly useful in musculoskeletal disorders. In the therapeutic range, O3 can be used as a more effective and safe substitute of standard medications. O3 therapy has been used for many years for its ability to inactivate various viruses, cancer, and acquired immune deficiency syndrome but is now making strides in the treatment of musculoskeletal disorders such as rheumatoid arthritis, lumbar facet joint syndrome, subacromial bursitis, carpal tunnel syndrome, osteoarthritis, hip bursitis, shoulder adhesive capsulitis, herniated disc, and temporomandibular joint disorder.

2.
J Cell Biol ; 211(2): 273-86, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26483556

RESUMO

Lethal giant larvae (Lgl) plays essential and conserved functions in regulating both cell polarity and tumorigenesis in Drosophila melanogaster and vertebrates. It is well recognized that plasma membrane (PM) or cell cortex localization is crucial for Lgl function in vivo, but its membrane-targeting mechanisms remain poorly understood. Here, we discovered that hypoxia acutely and reversibly inhibits Lgl PM targeting through a posttranslational mechanism that is independent of the well-characterized atypical protein kinase C (aPKC) or Aurora kinase-mediated phosphorylations. Instead, we identified an evolutionarily conserved polybasic (PB) domain that targets Lgl to the PM via electrostatic binding to membrane phosphatidylinositol phosphates. Such PB domain-mediated PM targeting is inhibited by hypoxia, which reduces inositol phospholipid levels on the PM through adenosine triphosphate depletion. Moreover, Lgl PB domain contains all the identified phosphorylation sites of aPKC and Aurora kinases, providing a molecular mechanism by which phosphorylations neutralize the positive charges on the PB domain to inhibit Lgl PM targeting.


Assuntos
Hipóxia Celular/fisiologia , Membrana Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Processamento de Proteína Pós-Traducional/genética , Proteínas Supressoras de Tumor/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Aurora Quinases/metabolismo , Proteínas de Drosophila/genética , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Dados de Sequência Molecular , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Estrutura Terciária de Proteína , Alinhamento de Sequência , Eletricidade Estática , Proteínas Supressoras de Tumor/genética
3.
Neuroscience ; 270: 168-176, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24747018

RESUMO

We have shown that intravenous immunoglobulin (IVIG) contains anti-Aß autoantibodies and IVIG could induce beta amyloid (Aß) efflux from cerebrospinal fluid (CSF) to blood in both Multiple Sclerosis (MS) and Alzheimer disease (AD) patients. However, the molecular mechanism underlying IVIG-induced Aß efflux remains unclear. In this study, we used amyloid precursor protein (AßPP) transgenic mice to investigate if the IVIG could induce efflux of Aß from the brain and whether low-density lipoprotein receptor-related protein-1 (LRP1), a hypothetic Aß transporter in blood-CSF barrier (BCB); could mediate this clearance process. We currently provide strong evidence to demonstrate that IVIG could reduce brain Aß levels by pulling Aß into the blood system in AßPP transgenic mice. In the mechanistic study, IVIG could induce Aß efflux through the in vitro BCB membrane formed by cultured BCB epithelial cells. Both receptor-associated protein (RAP; a functional inhibitor of LRP1), and LRP1 siRNA were able to significantly inhibit the Aß efflux. Should Aß prove to be the underlying cause of AD, our results strongly suggest that IVIG could be beneficial in the therapy for AD by inducing efflux of Aß from the brain through the LRP1 in the BCB.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Plexo Corióideo/efeitos dos fármacos , Plexo Corióideo/metabolismo , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Western Blotting , Técnicas de Cultura de Células , Linhagem Celular , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Técnicas de Silenciamento de Genes , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Interferente Pequeno/metabolismo , Ratos , Receptores de LDL/genética , Receptores de LDL/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
4.
Toxicol Sci ; 139(2): 432-51, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24614235

RESUMO

Regulation of cellular copper (Cu) homeostasis involves Cu-transporting ATPases (Cu-ATPases), i.e., ATP7A and ATP7B. The question as to how these Cu-ATPases in brain barrier systems transport Cu, i.e., toward brain parenchyma, cerebrospinal fluid (CSF), or blood, remained unanswered. This study was designed to characterize roles of Cu-ATPases in regulating Cu transport at the blood-brain barrier (BBB) and blood-CSF barrier (BCB) and to investigate how exposure to toxic manganese (Mn) altered the function of Cu-ATPases, thereby contributing to the etiology of Mn-induced parkinsonian disorder. Studies by quantitative real-time RT-PCR (qPCR), Western blot, and immunocytochemistry revealed that both Cu-ATPases expressed abundantly in BBB and BCB. Transport kinetic studies by in situ brain infusion and ventriculo-cisternal (VC) perfusion in Sprague Dawley rat suggested that the BBB was a major site for Cu entry into brain, whereas the BCB was a predominant route for Cu efflux from the CSF to blood. Confocal evidence showed that the presence of excess Cu or Mn in the choroid plexus cells led to ATP7A relocating toward the apical microvilli facing the CSF, but ATP7B toward the basolateral membrane facing blood. Mn exposure inhibited the production of both Cu-ATPases. Collectively, these data suggest that Cu is transported by the BBB from the blood to brain, which is mediated by ATP7A in brain capillary. By diffusion, Cu ions move from the interstitial fluid into the CSF, where they are taken up by the BCB. Within the choroidal epithelial cells, Cu ions are transported by ATP7B back to the blood. Mn exposure alters these processes, leading to Cu dyshomeostasis-associated neuronal injury.


Assuntos
Adenosina Trifosfatases/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Proteínas de Transporte de Cátions/metabolismo , Cloretos/toxicidade , Cobre/líquido cefalorraquidiano , Cobre/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/genética , Animais , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Proteínas de Transporte de Cátions/antagonistas & inibidores , Proteínas de Transporte de Cátions/genética , Cobre/farmacocinética , ATPases Transportadoras de Cobre , Técnicas de Silenciamento de Genes , Homeostase , Imuno-Histoquímica , Masculino , Compostos de Manganês , Microscopia Confocal , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Espectrofotometria Atômica
5.
PLoS One ; 7(11): e48899, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23185282

RESUMO

The neurotoxic effect of manganese (Mn) establishes itself in a condition known as manganism or Mn induced parkinsonism. While this condition was first diagnosed about 170 years ago, the mechanism of the neurotoxic action of Mn remains unknown. Moreover, the possibility that Mn exposure combined with other genetic and environmental factors can contribute to the development of Parkinson's disease has been discussed in the literature and several epidemiological studies have demonstrated a correlation between Mn exposure and an elevated risk of Parkinson's disease. Here, we introduce X-ray fluorescence imaging as a new quantitative tool for analysis of the Mn distribution in the brain with high spatial resolution. The animal model employed mimics deficits observed in affected human subjects. The obtained maps of Mn distribution in the brain demonstrate the highest Mn content in the globus pallidus, the thalamus, and the substantia nigra pars compacta. To test the hypothesis that Mn transport into/distribution within brain cells mimics that of other biologically relevant metal ions, such as iron, copper, or zinc, their distributions were compared. It was demonstrated that the Mn distribution does not follow the distributions of any of these metals in the brain. The majority of Mn in the brain was shown to occur in the mobile state, confirming the relevance of the chelation therapy currently used to treat Mn intoxication. In cells with accumulated Mn, it can cause neurotoxic action by affecting the mitochondrial respiratory chain. This can result in increased susceptibility of the neurons of the globus pallidus, thalamus, and substantia nigra pars compacta to various environmental or genetic insults. The obtained data is the first demonstration of Mn accumulation in the substantia nigra pars compacta, and thus, can represent a link between Mn exposure and its potential effects for development of Parkinson's disease.


Assuntos
Diagnóstico por Imagem/métodos , Manganês/toxicidade , Neurotoxinas/toxicidade , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Cobre/metabolismo , Modelos Animais de Doenças , Fluorescência , Humanos , Ferro/metabolismo , Ratos , Raios X , Zinco/metabolismo
6.
J Toxicol ; 2011: 628151, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21776263

RESUMO

Harmane, a potent neurotoxin linked with several neurological disorders, is present in many foods, coffee, and cigarettes. We assessed whether morning food/coffee consumption and smoking were reflected in blood harmane concentrations (BHCs) we obtained in an epidemiologic sample (n = 497). Participants who smoked on the morning of phlebotomy had similar logBHCs to those who had not smoked (P = .57); there was no correlation between logBHCs and number of cigarettes (P = .59). Among the coffee drinkers, there was no correlation between number of cups and logBHCs (P = .98). Participants who had eaten on the morning of phlebotomy had similar logBHCs to those who had not (P = .49); logBHCs did not correlate with the time latency between last food consumption and phlebotomy (P = .74). BHCs in this sample of ~500 individuals did not covary with recent smoking, coffee, or food consumption, suggesting that our inability to withhold these exposures on the morning of phlebotomy was not reflected in the BHCs we measured.

7.
Toxicol Appl Pharmacol ; 240(2): 245-54, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19501112

RESUMO

The choroid plexus, a barrier between the blood and cerebrospinal fluid (CSF), is known to accumulate lead (Pb) and also possibly function to maintain brain's homeostasis of Abeta, an important peptide in the etiology of Alzheimer's disease. This study was designed to investigate if Pb exposure altered Abeta levels at the blood-CSF barrier in the choroid plexus. Rats received ip injection of 27 mg Pb/kg. Twenty-four hours later, a FAM-labeled Abeta (200 pmol) was infused into the lateral ventricle and the plexus tissues were removed to quantify Abeta accumulation. Results revealed a significant increase in intracellular Abeta accumulation in the Pb-exposed animals compared to controls (p<0.001). When choroidal epithelial Z310 cells were treated with 10 microM Pb for 24 h and 48 h, Abeta (2 microM in culture medium) accumulation was significantly increased by 1.5 fold (p<0.05) and 1.8 fold (p<0.05), respectively. To explore the mechanism, we examined the effect of Pb on low-density lipoprotein receptor protein-1 (LRP1), an intracellular Abeta transport protein. Following acute Pb exposure with the aforementioned dose regimen, levels of LRP1 mRNA and proteins in the choroid plexus were decreased by 35% (p<0.05) and 31.8% (p<0.05), respectively, in comparison to those of controls. In Z310 cells exposed to 10 microM Pb for 24 h and 48 h, a 33.1% and 33.4% decrease in the protein expression of LRP1 was observed (p<0.05), respectively. Knocking down LRP1 resulted in even more substantial increases of cellular accumulation of Abeta, from 31% in cells without knockdown to 72% in cells with LRP1 knockdown (p<0.05). Taken together, these results suggest that the acute exposure to Pb results in an increased accumulation of intracellular Abeta in the choroid plexus; the effect appears to be mediated, at least in part, via suppression of LRP1 production following Pb exposure.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Plexo Corióideo/efeitos dos fármacos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Compostos Organometálicos/toxicidade , Fragmentos de Peptídeos/metabolismo , Peptídeos beta-Amiloides/administração & dosagem , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Plexo Corióideo/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Injeções Intraperitoneais , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Masculino , Compostos Organometálicos/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Perfusão , Interferência de RNA , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Regulação para Cima
9.
Mov Disord ; 23(12): 1747-51, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18709680

RESUMO

Blood concentrations of harmane, a tremor-producing neurotoxin, are elevated in essential tremor (ET). Harmane is also a comutagen. Using a case-control design, we compared the prevalence of cancer in ET cases vs. controls, and determined whether blood harmane concentrations are elevated among ET cases with cancer. 66/267 (24.7%) ET cases vs. 55/331 (16.6%) controls had cancer (adjusted OR 1.52, 95% CI 1.01-2.30, P = 0.04). Among specific cancer types, colon cancer was more prevalent in ET cases than controls (2.6% vs. 0.6%, P = 0.04). Log blood harmane concentration was higher in ET cases vs. controls (P = 0.02) and in participants with vs. without cancer (P = 0.02). Log blood harmane concentration was highest in ET cases with cancer when compared with other groups (P = 0.009). These links between cancer and ET and between high blood harmane and cancer in ET deserve further study.


Assuntos
Tremor Essencial/sangue , Tremor Essencial/genética , Harmina/análogos & derivados , Neoplasias/sangue , Neoplasias/genética , Idoso , Distribuição de Qui-Quadrado , Feminino , Harmina/sangue , Harmina/genética , Humanos , Masculino , Pessoa de Meia-Idade
10.
Neurotoxicology ; 29(3): 466-70, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18400301

RESUMO

Manganese (Mn) is known to pass across the blood-brain barrier and interact with dopaminergic neurons. However, the knowledge on the subcellular distribution of Mn in these cell types upon exposure to Mn remained incomplete. This study was designed to investigate the subcellular distribution of Mn in blood-brain barrier endothelial RBE4 cells, blood-cerebrospinal fluid barrier choroidal epithelial Z310 cells, mesencephalic dopaminergic neuronal N27 cells, and pheochromocytoma dopaminergic PC12 cells. The cells were incubated with 100 microM MnCl(2) with radioactive tracer (54)Mn in the culture media for 24h. The subcellular organelles, i.e., nuclei, mitochondria, microsomes, and cytoplasm, were isolated by centrifugation and verified for their authenticity by determining the markers specific to cellular organelles. Data indicated that maximum Mn accumulation was observed in PC12 cells, which was 2.8, 5.2- and 5.9-fold higher than that in N27, Z310 and RBE4 cells, respectively. Within cells, about 92%, 72%, and 52% of intracellular (54)Mn were found to be present in nuclei of RBE4, Z310, and N27 cells, respectively. The recovery of (54)Mn in nuclei and cytoplasm of PC12 cells were 27% and 69%, respectively. Surprisingly, less than 0.5% and 2.5% of cellular (54)Mn was found in mitochondrial and microsomal fractions, respectively. This study suggests that the nuclei may serve as the primary pool for intracellular Mn; mitochondria and microsomes may play an insignificant role in Mn subcellular distribution.


Assuntos
Encéfalo/citologia , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Manganês/metabolismo , Encéfalo/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Humanos , Mitocôndrias/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/isolamento & purificação , Radioisótopos , Frações Subcelulares/metabolismo
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