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1.
Support Care Cancer ; 29(1): 533-534, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32940769

RESUMO

This article has been retracted. Please see the retraction notice for more detail: https://doi.org/10.1007/s00520-020-05770-w.

2.
Support Care Cancer ; 25(4): 1279-1289, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27966023

RESUMO

PURPOSE: High-dose chemotherapy prior to autologous stem cell transplantation (ASCT) leads to adverse effects including mucositis, neutropenia and bacteremia. To reduce the toxicity, we treated myeloma and lymphoma patients with peroral bismuth as an adjuvant to chemotherapy to convey cytoprotection in non-malignant cells. METHODS: This trial was a prospective, randomised, double-blind, placebo-controlled pilot study of hematological inpatients (n = 50) receiving bismuth or placebo tablets, in order to identify any potential superiority of bismuth on toxicity from chemotherapy. RESULTS: We show for the first time that bismuth significantly reduces grade 2 stomatitis, febrile neutropenia and infections caused by melphalan in multiple myeloma, where adverse effects also were significantly linked to gender. In lymphoma patients, bismuth significantly reduces diarrhoea relative to placebo. Also, lymphoma patients' adverse effects were linked to gender. For the first time, bismuth is demonstrated as a safe strategy against chemotherapy's toxicity without interfering with intentional anti-cancer efficiency. Also, we show how gender significantly influences various adverse effects and response to treatment in both multiple myeloma and malignant lymphomas. CONCLUSION: These results may impact clinical prevention of chemotherapy's cytotoxicity in certain patient groups, and also, this study may direct further attention towards the impact of gender during the course and treatment outcome of malignant disorders.


Assuntos
Bismuto/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Linfoma/tratamento farmacológico , Mieloma Múltiplo/tratamento farmacológico , Condicionamento Pré-Transplante/métodos , Transplante Autólogo/métodos , Idoso , Bismuto/administração & dosagem , Bismuto/farmacologia , Método Duplo-Cego , Feminino , Humanos , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
3.
Histochem Cell Biol ; 138(5): 787-802, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22820857

RESUMO

Multiple sclerosis (MS) is the most common neurodegenerative disease in the Western world affecting younger, otherwise healthy individuals. Today no curative treatment exists. Patients suffer from recurring attacks caused by demyelination and underlying neuroinflammation, ultimately leading to loss of neurons. Recent research shows that bio-liberation of gold ions from metallic gold implants can ameliorate inflammation, reduce apoptosis and promote proliferation of neuronal stem cells (NSCs) in a mouse model of focal brain injury. Based on these findings, the present study investigates whether metallic gold implants affect the clinical signs of disease progression and the pathological findings in experimental autoimmune encephalomyelitis (EAE), a rodent model of MS. Gold particles 20-45 µm suspended in hyaluronic acid were bilaterally injected into the lateral ventricles (LV) of young Lewis rats prior to EAE induction. Comparing gold-treated animals to untreated and vehicle-treated ones, a statistically significant slowing of disease progression in terms of reduced weight loss was seen. Despite massive inflammatory infiltration, terminal deoxynucleotidyl transferase dUTP nick end labeling staining revealed reduced apoptotic cell death in disease foci in the brain stem of gold-treated animals, alongside an up-regulation of glial fibrillary acidic protein-positive reactive astrocytes near the LV and in the brain stem. Cell counting of frizzled-9 and nestin-stained cells showed statistically significant up-regulation of NSCs migrating from the subventricular zone. Additionally, the neuroprotective proteins Metallothionein-1 and -2 were up-regulated in the corpus callosum. In conclusion, this study is the first to show that the presence of small gold implants affect disease progression in a rat model of MS, increasing the neurogenic response and reducing the loss of cells in disease foci. Gold implants might thus improve clinical outcome for MS patients and further research into the long-term effects of such localized gold treatment is warranted.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Gliose/induzido quimicamente , Ouro/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Animais , Tronco Encefálico/química , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/patologia , Movimento Celular/efeitos dos fármacos , Corpo Caloso/química , Corpo Caloso/efeitos dos fármacos , Corpo Caloso/patologia , Modelos Animais de Doenças , Progressão da Doença , Encefalomielite Autoimune Experimental/patologia , Feminino , Proteína Glial Fibrilar Ácida/análise , Gliose/patologia , Proteínas de Filamentos Intermediários/análise , Ventrículos Laterais/efeitos dos fármacos , Ventrículos Laterais/patologia , Metalotioneína/análise , Esclerose Múltipla/patologia , Proteínas do Tecido Nervoso/análise , Nestina , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/patologia , Ratos , Ratos Endogâmicos Lew , Receptores de Neurotransmissores/análise , Regulação para Cima/efeitos dos fármacos
4.
Exp Parasitol ; 127(2): 500-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21044627

RESUMO

Cerebral malaria (CM) causes substantial mortality and neurological sequelae in survivors, and no neuroprotective regimens are currently available for this condition. Erythropoietin (EPO) reduces neuropathology and improves survival in murine CM. Using the Plasmodium berghei model of CM, we investigated if EPO's neuroprotective effects include activation of endogenous neural stem cells (NSC). By using immunohistochemical markers of different NSC maturation stages, we show that EPO increased the number of nestin(+) cells in the dentate gyrus and in the sub-ventricular zone of the lateral ventricles, relative to control-treatment. 75% of the EPO-treated CM mice displayed migration as nestin(+) NSC. The NSC showed differentiation towards a neural cell lineage as shown by PSA-NCAM binding and NSC maturation and lineage commitment was significantly affected by exogenous EPO and by CM in the sub ventricular zone. These results indicate a rapid, EPO-dependent activation of NSC during CM pathology.


Assuntos
Eritropoetina/uso terapêutico , Malária Cerebral/tratamento farmacológico , Células-Tronco Neurais/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Plasmodium berghei , Análise de Variância , Animais , Modelos Animais de Doenças , Eritropoetina/farmacologia , Feminino , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/análise , Malária Cerebral/patologia , Malária Cerebral/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/análise , Nestina , Molécula L1 de Adesão de Célula Nervosa/análise , Células-Tronco Neurais/química , Células-Tronco Neurais/citologia , Neuritos/fisiologia , Fármacos Neuroprotetores/farmacologia , Ácidos Siálicos/análise , Organismos Livres de Patógenos Específicos
5.
Glia ; 58(10): 1220-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20544857

RESUMO

Neuroglobin (Ngb) is proposed to be a neuron-specific, hypoxia-responsive, neuroprotective protein. However, results are conflicting concerning both Ngb's physiological and pathological significance. This study was designed to investigate the in vivo localization and regulation of Ngb in different neuropathological models representing traumatic injury, infectious, autoimmune, and excitotoxic pathogeneses. We profiled Ngb immunohistochemistry in murine models of traumatic brain injury, cerebral malaria, experimental autoimmune encephalitis, and kainic acid (KA)-mediated epileptic seizures that, to our knowledge, have not been studied in the context of Ngb. In control mice Ngb was expressed exclusively in neurons. In all pathological models except KA, in addition to neurons Ngb was present in reactive astrocytes. Ngb positive astrocytes were found within regions associated with most severe pathology and the astroglial scar. This is the first report of Ngb present in reactive astroglia and in scar-forming astrocytes in response to different pathological conditions relevant to human disease. In light of previously reported cyto-protective properties of Ngb, further insight may result in therapeutic ramifications.


Assuntos
Astrócitos/metabolismo , Doenças Autoimunes do Sistema Nervoso/metabolismo , Lesões Encefálicas/metabolismo , Encefalite/metabolismo , Globinas/metabolismo , Malária Cerebral/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Astrócitos/patologia , Doenças Autoimunes do Sistema Nervoso/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Encefalite/patologia , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Epilepsia/patologia , Feminino , Imuno-Histoquímica , Ácido Caínico , Malária Cerebral/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuroglobina , Neurônios/metabolismo , Neurônios/patologia
6.
Cerebrospinal Fluid Res ; 7: 20, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-21054845

RESUMO

BACKGROUND: The water channel protein aquaporin-4 (AQP4) is reported to be of possible major importance for accessory cerebrospinal fluid (CSF) circulation pathways. We hypothesized that changes in AQP4 expression in specific brain regions correspond to the severity and duration of hydrocephalus. METHODS: Hydrocephalus was induced in adult rats (~8 weeks) by intracisternal kaolin injection and evaluated after two days, one week and two weeks. Using magnetic resonance imaging (MRI) we quantified lateral ventricular volume, water diffusion and blood-brain barrier properties in hydrocephalic and control animals. The brains were analysed for AQP4 density by western blotting and localisation by immunohistochemistry. Double fluorescence labelling was used to study cell specific origin of AQP4. RESULTS: Lateral ventricular volume was significantly increased over control at all time points after induction and the periventricular apparent diffusion coefficient (ADC) value significantly increased after one and two weeks of hydrocephalus. Relative AQP4 density was significantly decreased in both cortex and periventricular region after two days and normalized after one week. After two weeks, periventricular AQP4 expression was significantly increased. Relative periventricular AQP4 density was significantly correlated to lateral ventricular volume. AQP4 immunohistochemical analysis demonstrated the morphological expression pattern of AQP4 in hydrocephalus in astrocytes and ventricular ependyma. AQP4 co-localized with astrocytic glial fibrillary acidic protein (GFAP) in glia limitans. In vascular structures, AQP4 co-localized to astroglia but not to microglia or endothelial cells. CONCLUSIONS: AQP4 levels are significantly altered in a time and region dependent manner in kaolin-induced hydrocephalus. The presented data suggest that AQP4 could play an important neurodefensive role, and may be a promising future pharmaceutical target in hydrocephalus and CSF disorders.

7.
Prog Histochem Cytochem ; 44(1): 1-27, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19348909

RESUMO

In traumatic brain injury (TBI), the primary, irreversible damage associated with the moment of impact consists of cells dying from necrosis. This contributes to fuelling a chronic central nervous system (CNS) inflammation with increased formation of proinflammatory cytokines, enzymes and reactive oxygen species (ROS). ROS promote oxidative stress, which leads to neurodegeneration and ultimately results in programmed cell death (secondary injury). Since this delayed, secondary tissue loss occurs days to months following the primary injury it provides a therapeutic window where potential neuroprotective treatment could alleviate ongoing neurodegeneration, cell death and neurological impairment following TBI. Various neuroprotective drug candidates have been described, tested and proven effective in pre-clinical studies, including glutamate receptor antagonists, calcium-channel blockers, and caspase inhibitors. However, most of the scientific efforts have failed in translating the experimental results into clinical trials. Despite intensive research, effective neuroprotective therapies are lacking in the clinic, and TBI continues to be a major cause of morbidity and mortality. This paper provides an overview of the TBI pathophysiology leading to cell death and neurological impairment. We also discuss endogenously expressed neuroprotectants and drug candidates, which at this stage may still hold the potential for treating brain injured patients.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Metalotioneína/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Lesões Encefálicas/fisiopatologia , Morte Celular , Humanos
8.
Prog Histochem Cytochem ; 44(1): 29-64, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19348910

RESUMO

The antiapoptotic, antioxidant, proliferative, and angiogenic effects of metallothionein (MT)-I+II has resulted in increased focus on their role in oncogenesis, tumor progression, therapy response, and patient prognosis. Studies have reported increased expression of MT-I+II mRNA and protein in various human cancers; such as breast, kidney, lung, nasopharynx, ovary, prostate, salivary gland, testes, urinary bladder, cervical, endometrial, skin carcinoma, melanoma, acute lymphoblastic leukemia (ALL), and pancreatic cancers, where MT-I+II expression is sometimes correlated to higher tumor grade/stage, chemotherapy/radiation resistance, and poor prognosis. However, MT-I+II are downregulated in other types of tumors (e.g. hepatocellular, gastric, colorectal, central nervous system (CNS), and thyroid cancers) where MT-I+II is either inversely correlated or unrelated to mortality. Large discrepancies exist between different tumor types, and no distinct and reliable association exists between MT-I+II expression in tumor tissues and prognosis and therapy resistance. Furthermore, a parallel has been drawn between MT-I+II expression as a potential marker for prognosis, and MT-I+II's role as oncogenic factors, without any direct evidence supporting such a parallel. This review aims at discussing the role of MT-I+II both as a prognostic marker for survival and therapy response, as well as for the hypothesized role of MT-I+II as causal oncogenes.


Assuntos
Biomarcadores Tumorais , Metalotioneína/fisiologia , Neoplasias/diagnóstico , Neoplasias/fisiopatologia , Biomarcadores Tumorais/química , Humanos , Metalotioneína/química , Metalotioneína/classificação , Neoplasias/mortalidade , Prognóstico
9.
J Neurosci Res ; 87(13): 2926-36, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19405100

RESUMO

Metallothionein (MT) belongs to a family of metal-binding cysteine-rich proteins comprising several structurally related proteins implicated in tissue protection and regeneration after injuries and functioning as antiapoptotic antioxidants in neurological disorders. This has been demonstrated in animals receiving MT treatment and in mice with endogenous MT overexpression or null mutation during various experimental models of neuropathology, and also in patients with Alzheimer's disease and amyotrophic lateral sclerosis. Exogenously applied MT increases neurite outgrowth and neuronal survival in rat cerebellar, hippocampal, dopaminergic, and cortical neurons in vitro. In this study, the intraneuronal signaling involved in MT-mediated neuritogenesis was examined. The MT-induced neurite outgrowth in cultures of cerebellar granule neurons was dependent on activation of a heterotrimeric G-protein-coupled pathway but not on protein tyrosine kinases or on receptor tyrosine kinases. Activation of phospholipase C was necessary for MT-induced neurite outgrowth, and furthermore it was shown that inhibition of several intracellular protein kinases, such as protein kinase A, protein kinase C, phosphatidylinositol 3-kinase, Ca(2+)/calmodulin kinase-II, and mitogen-activated protein kinase kinase, abrogated the MT-mediated neuritogenic response. In addition, exogenously applied MT resulted in a decrease in phosphorylation of intraneuronal kinases implicated in proinflammatory reactions and apoptotic cell death, such as glycogen synthase-serine kinase 3alpha, Jun, and signal transducer and activator of transcription 3. This paper elucidates the intraneuronal molecular signaling involved in neuroprotective effects of MT.


Assuntos
Metalotioneína/farmacologia , Proteínas do Tecido Nervoso/fisiologia , Neuritos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas/efeitos dos fármacos , Cerebelo/citologia , Avaliação Pré-Clínica de Medicamentos , Proteínas Heterotriméricas de Ligação ao GTP/fisiologia , Metalotioneína/administração & dosagem , Metalotioneína/fisiologia , Fármacos Neuroprotetores/administração & dosagem , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/fisiologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/fisiologia , Coelhos , Ratos , Ratos Wistar , Fator de Transcrição STAT3/fisiologia , Transdução de Sinais/fisiologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/fisiologia
10.
J Neurochem ; 104(1): 21-37, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17986228

RESUMO

Accumulating evidence suggests that metallothionein (MT)-I and -II promote neuronal survival and regeneration in vivo. The present study investigated the molecular mechanisms underlying the differentiation and survival-promoting effects of MT and a peptide modeled after MT, EmtinB. Both MT and EmtinB directly stimulated neurite outgrowth and promoted survival in vitro using primary cultures of cerebellar granule neurons. In addition, expression and surface localization of megalin, a known MT receptor, and the related lipoprotein receptor-related protein-1 (LRP) are demonstrated in cerebellar granule neurons. By means of surface plasmon resonance MT and EmtinB were found to bind to both megalin and LRP. The bindings were abrogated in the presence of receptor-associated protein-1, an antagonist of the low-density lipoprotein receptor family, which also inhibited MT- and EmtinB-induced neurite outgrowth and survival. MT-mediated neurite outgrowth was furthermore inhibited by an anti-megalin serum. EmtinB-mediated inhibition of apoptosis occurred without a reduction of caspase-3 activity, but was associated with reduced expression of the pro-apoptotic B-cell leukemia/lymphoma-2 interacting member of cell death (Bim(S)). Finally, evidence is provided that MT and EmtinB activate extracellular signal-regulated kinase, protein kinase B, and cAMP response element binding protein. Altogether, these results strongly suggest that MT and EmtinB induce their neuronal effects through direct binding to surface receptors belonging to the low-density lipoprotein receptor family, such as megalin and LRP, thereby activating signal transduction pathways resulting in neurite outgrowth and survival.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Metalotioneína/farmacologia , Neurônios/efeitos dos fármacos , Peptídeos/farmacologia , Receptores de LDL/fisiologia , Análise de Variância , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cerebelo/citologia , Relação Dose-Resposta a Droga , Marcação In Situ das Extremidades Cortadas/métodos , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Associada a Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Metalotioneína/química , Modelos Biológicos , Neuritos/efeitos dos fármacos , Peptídeos/química , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia , Ressonância de Plasmônio de Superfície/métodos
11.
Neurosci Lett ; 437(2): 148-53, 2008 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18436381

RESUMO

Cerebral responses to traumatic brain injury (TBI) include up- and downregulation of a vast number of proteins involved in endogenous inflammatory responses and defense mechanisms developing postinjury. The present study analyzed the global gene expression profile in response to cryo-induced TBI by means of microarray analysis. Adolescent rats were subjected to TBI and treated with either placebo or a neural cell adhesion molecule (NCAM)-derived fibroblast growth factor receptor (FGFR) agonist, FGL peptide, which has been demonstrated to have neuroprotective effects. mRNA levels were measured at various time-points postlesion (6 h, 1 day and 4 days). The effects of injury, treatment, and injury-treatment interaction were observed. TBI alone rendered a large number of genes affected. Analysis of lesion and treatment interactions resulted in a clear effect of the interaction between injury and FGL-treatment compared to injury and placebo-treatment. Genes affected by TBI alone included inflammation markers, protein kinases, ion channel members and growth factors. Genes encoding regulators of apoptosis, signal transduction and metabolism were altered by the interaction between FGL-treatment and TBI. FGL-treatment in non-injured animals rendered genes regulating signaling, transport and cytoskeleton maintenance significantly increased. Thus, the hypothesis of a putative neuroprotective role of FGL was supported by our findings.


Assuntos
Lesões Encefálicas/genética , Lesões Encefálicas/fisiopatologia , Encéfalo/fisiologia , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Ativação Transcricional/fisiologia , Animais , Regulação para Baixo/fisiologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Wistar , Regulação para Cima/fisiologia
12.
Malar J ; 7: 3, 2008 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-18179698

RESUMO

BACKGROUND: Cerebral malaria (CM) is an acute encephalopathy with increased pro-inflammatory cytokines, sequestration of parasitized erythrocytes and localized ischaemia. In children CM induces cognitive impairment in about 10% of the survivors. Erythropoietin (Epo) has - besides of its well known haematopoietic properties - significant anti-inflammatory, antioxidant and anti-apoptotic effects in various brain disorders. The neurobiological responses to exogenously injected Epo during murine CM were examined. METHODS: Female C57BL/6j mice (4-6 weeks), infected with Plasmodium berghei ANKA, were treated with recombinant human Epo (rhEpo; 50-5000 U/kg/OD, i.p.) at different time points. The effect on survival was measured. Brain pathology was investigated by TUNEL (Terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-digoxigenin nick end labelling), as a marker of apoptosis. Gene expression in brain tissue was measured by real time PCR. RESULTS: Treatment with rhEpo increased survival in mice with CM in a dose- and time-dependent manner and reduced apoptotic cell death of neurons as well as the expression of pro-inflammatory cytokines in the brain. This neuroprotective effect appeared to be independent of the haematopoietic effect. CONCLUSION: These results and its excellent safety profile in humans makes rhEpo a potential candidate for adjunct treatment of CM.


Assuntos
Apoptose/efeitos dos fármacos , Eritropoetina/uso terapêutico , Malária Cerebral/tratamento farmacológico , Neurônios/efeitos dos fármacos , Plasmodium berghei/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Encéfalo/parasitologia , Encéfalo/patologia , Citocinas/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eritropoetina/administração & dosagem , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Malária Cerebral/mortalidade , Malária Cerebral/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/parasitologia , Neurônios/patologia , Plasmodium berghei/crescimento & desenvolvimento , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Fatores de Tempo
13.
Int J Biochem Cell Biol ; 39(3): 484-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17097331

RESUMO

Metallothioneins (MTs) constitutes a superfamily of highly conserved, low molecular weight polypeptides, which are characterized by high contents of cysteine (sulphur) and metals. As intracellular metal-binding proteins they play a significant role in the regulation of essential metals. The major isoforms of the protein (MT-I and MT-II) are induced by numerous stimuli and pathogens but most importantly their induction by metals is closely linked to the physiological metabolism of zinc and protection from the toxic affects following heavy metal exposure. Although the preservation of their genetic expression across animal phyla suggests that MTs may play an important physiological role, MT-I, II knock out (KO) mice survive to adulthood. In both central and peripheral nervous tissues, MT-I, II have neuroprotective roles, which are also induced by exogenous MT-I and/or MT-II treatment. Hence, MT-I, II may provide neurotherapeutic targets offering protection against neuronal injury and degeneration.


Assuntos
Sistema Nervoso Central/metabolismo , Metalotioneína/metabolismo , Animais , Sistema Nervoso Central/lesões , Sistema Nervoso Central/patologia , Humanos , Metalotioneína/química , Metalotioneína/deficiência , Metalotioneína/genética , Camundongos , Camundongos Knockout , Modelos Biológicos , Modelos Moleculares , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/deficiência , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos
14.
Stroke ; 38(3): 1025-30, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17272771

RESUMO

BACKGROUND AND PURPOSE: Exposure of animals for a few hours to moderate hypoxia confers relative protection against subsequent ischemic brain damage. This phenomenon, known as hypoxic preconditioning, depends on new RNA and protein synthesis, but its molecular mechanisms are poorly understood. Increased expression of IL-6 is evident, particularly in the lungs of animals subjected to hypoxic preconditioning. Stanniocalcin-1 (STC-1) is a 56-kDa homodimeric glycoprotein originally discovered in bony fish, where it regulates calcium/phosphate homeostasis and protects against toxic hypercalcemia. We originally reported expression of mammalian STC-1 in brain neurons and showed that STC-1 guards neurons against hypercalcemic and hypoxic damage. METHODS: We treated neural Paju cells with IL-6 and measured the induction of STC-1 mRNA. In addition, we quantified the effect of hypoxic preconditioning on Stc-1 mRNA levels in brains of wild-type and IL-6 deficient mice. Furthermore, we monitored the Stc-1 response in brains of wild-type and transgenic mice, overexpressing IL-6 in the astroglia, before and after induced brain injury. RESULTS: Hypoxic preconditioning induced an upregulated expression of Stc-1 in brains of wild-type but not of IL-6-deficient mice. Induced brain injury elicited a stronger STC-1 response in brains of transgenic mice, with targeted astroglial IL-6 expression, than in brains of wild-type mice. Moreover, IL-6 induced STC-1 expression via MAPK signaling in neural Paju cells. CONCLUSIONS: These findings indicate that IL-6-mediated expression of STC-1 is one molecular mechanism of hypoxic preconditioning-induced tolerance to brain ischemia.


Assuntos
Encéfalo/metabolismo , Glicoproteínas/biossíntese , Interleucina-6/fisiologia , Precondicionamento Isquêmico/métodos , Sistema de Sinalização das MAP Quinases/fisiologia , Fármacos Neuroprotetores/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Células Cultivadas , Glicoproteínas/genética , Humanos , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Interleucina-6/deficiência , Interleucina-6/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia
15.
Diabetes ; 54(11): 3089-94, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16249430

RESUMO

Oxidative stress is implicated in diabetes complications, during which endogenous antioxidant defenses have important pathophysiological consequences. To date, the significance of endogenous antioxidants such as metallothioneins I and II (MT-I+II) in type 2 diabetes remains unclear. To examine the MT-I+II-mediated antioxidant capacity and its response to exercise training in the skeletal muscle of patients with type 2 diabetes, biopsies and blood samples were taken from 13 matched subjects (type 2 diabetes n = 8, control subjects n = 5) both before and after 8 weeks of exercise training. Immunohistochemical analysis revealed reduced MT-I+II levels in the skeletal muscle of type 2 diabetic subjects compared with control subjects. Control subjects produced a robust increase of MT-I+II in response to training; however, in type 2 diabetes, MT-I+II levels remained essentially unchanged. Significantly lower levels of MT-I+II were also detected in the plasma of type 2 diabetic subjects compared with control subjects. These results suggest that, in control subjects, the MT-I+II defense system is active and inducible within skeletal muscle tissue and plasma. In type 2 diabetes, reduced levels of MT-I+II in muscle and plasma, as well as the deficient MT-I+II response to exercise, indicate that this antioxidant defense is impaired. This study presents a novel candidate in the pathogenesis of complications related to oxidative stress in type 2 diabetes.


Assuntos
Antioxidantes/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Exercício Físico/fisiologia , Metalotioneína/metabolismo , Estudos de Casos e Controles , Regulação da Expressão Gênica , Humanos , Masculino , Metalotioneína/genética , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Estresse Oxidativo , RNA Mensageiro/metabolismo
16.
FEBS J ; 273(9): 1857-70, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16640552

RESUMO

Metallothioneins (MTs) constitute a family of cysteine-rich metalloproteins involved in cytoprotection during pathology. In mammals there are four isoforms (MT-I - IV), of which MT-I and -II (MT-I + II) are the best characterized MT proteins in the brain. Accumulating studies have demonstrated MT-I + II as multipurpose factors important for host defense responses, immunoregulation, cell survival and brain repair. This review will focus on expression and roles of MT-I + II in the disordered brain. Initially, studies of genetically modified mice with MT-I + II deficiency or endogenous MT-I overexpression demonstrated the importance of MT-I + II for coping with brain pathology. In addition, exogenous MT-I or MT-II injected intraperitoneally is able to promote similar effects as those of endogenous MT-I + II, which indicates that MT-I + II have both extra- and intracellular actions. In injured brain, MT-I + II inhibit macrophages, T lymphocytes and their formation of interleukins, tumor necrosis factor-alpha, matrix metalloproteinases, and reactive oxygen species. In addition, MT-I + II enhance cell cycle progression, mitosis and cell survival, while neuronal apoptosis is inhibited. The precise mechanisms downstream of MT-I + II have not been fully established, but convincing data show that MT-I + II are essential for coping with neuropathology and for brain recovery. As MT-I and/or MT-II compounds are well tolerated, they may provide a potential therapy for a range of brain disorders.


Assuntos
Química Encefálica/fisiologia , Encéfalo/patologia , Metalotioneína/fisiologia , Fármacos Neuroprotetores/metabolismo , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/fisiologia , Humanos
17.
FASEB J ; 19(9): 1181-3, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15837717

RESUMO

Contracting muscle fibers produce and release IL-6, and plasma levels of this cytokine are markedly elevated in response to physical exercise. We recently showed autocrine regulation of IL-6 in human skeletal muscle in vivo and hypothesized that this may involve up-regulation of the IL-6 receptor. Therefore, we investigated IL-6 receptor regulation in response to exercise and IL-6 infusion in humans. Furthermore, using IL-6-deficient mice, we investigated the role of IL-6 in the IL-6 receptor response to exercise. Human skeletal muscle biopsies were obtained in relation to: 3 h of bicycle exercise and rest (n=6+5), or recombinant human IL-6 infusion (rhIL-6) or saline infusion (n=6+6). We further obtained skeletal muscle samples from IL-6 knockout (KO) mice and wild-type C57/BL-6 mice in response to a 1-h bout of exercise. In exercising human skeletal muscle, IL-6 receptor mRNA increased sixfold with a peak at 6 h postexercise. Detection of the IL-6 receptor protein by immunohistochemistry revealed a pronounced staining following exercise that was primarily located at the cell membrane of the muscle fibers, whereas muscle gp130 expression and plasma levels of soluble IL-6 receptor were unaffected. Infusion of rhIL-6 to humans had no effect on the mRNA level of the IL-6 receptor, whereas there was an increase at the protein level. IL-6 receptor mRNA increased similarly in muscle of both IL-6 KO mice and wild-type mice in response to exercise. In conclusion, exercise increases IL-6 receptor production in human skeletal muscle. This effect is most prominent 6 h after the end of the exercise bout, suggesting a postexercise-sensitizing mechanism to IL-6 when plasma IL-6 is concomitantly low. Exercise-induced increases in IL-6 receptor mRNA most likely occurs via an IL-6 independent mechanism as shown in IL-6 KO mice and the human rhIL-6 infusion study, whereas IL-6 receptor protein levels are responsive to elevated plasma IL-6 levels.


Assuntos
Exercício Físico , Interleucina-6/fisiologia , Músculo Esquelético/metabolismo , Receptores de Interleucina-6/genética , Adulto , Animais , Receptor gp130 de Citocina/fisiologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/análise
18.
J Appl Physiol (1985) ; 101(3): 817-25, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16794029

RESUMO

The metabolic profile of rodent muscle is generally reflected in the myosin heavy chain (MHC) fiber-type composition. The present study was conducted to test the hypothesis that metabolic gene expression is not tightly coupled with MHC fiber-type composition for all genes in human skeletal muscle. Triceps brachii, vastus lateralis quadriceps, and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers, because these muscles are characterized by different fiber-type compositions. As expected, citrate synthase and 3-hydroxyacyl dehydrogenase activity was more than twofold higher in soleus and vastus than in triceps. Contrary, phosphofructokinase and total lactate dehydrogenase (LDH) activity was approximately three- and twofold higher in triceps than in both soleus and vastus. Expression of metabolic genes was assessed by determining the mRNA content of a broad range of metabolic genes. The triceps muscle had two- to fivefold higher MHC IIa, phosphofructokinase, and LDH A mRNA content and two- to fourfold lower MHC I, lipoprotein lipase, CD36, hormone-sensitive lipase, and LDH B and hexokinase II mRNA than vastus lateralis or soleus. Interestingly, such mRNA differences were not evident for any of the genes encoding mitochondrial oxidative proteins, 3-hydroxyacyl dehydrogenase, carnitine palmitoyl transferase I, citrate synthase, alpha-ketogluterate dehydrogenase, and cytochrome c, nor for the transcriptional regulators peroxisome proliferator activator receptor gamma coactivator-1alpha, forkhead box O1, or peroxisome proliferator activator receptor-alpha. Thus the mRNA expression of genes encoding mitochondrial proteins and transcriptional regulators does not seem to be fiber type specific as the genes encoding glycolytic and lipid metabolism genes, which suggests that basal mRNA regulation of genes encoding mitochondrial proteins does not match the wide differences in mitochondrial content of these muscles.


Assuntos
Metabolismo Energético/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/metabolismo , RNA Mensageiro/metabolismo , Adulto , Células Cultivadas , Expressão Gênica/fisiologia , Perfilação da Expressão Gênica , Humanos , Masculino , Proteínas Musculares/genética , Cadeias Pesadas de Miosina/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Distribuição Tecidual
19.
Exp Biol Med (Maywood) ; 231(9): 1450-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17018866

RESUMO

In recent years it has become increasingly clear that the metallothionein (MT) family of proteins is important in neurobiology. MT-I and MT-II are normally dramatically up-regulated by neuroinflammation. Results for MT-III are less clear. MTs could also be relevant in human neuropathology. In Alzheimer disease (AD), a major neurodegenerative disease, clear signs of inflammation and oxidative stress were detected associated with amyloid plaques. Furthermore, the number of cells expressing apoptotic markers was also significantly increased in these plaques. As expected, MT-I and MT-II immunostaining was dramatically increased in cells surrounding the plaques, consistent with astrocytosis and microgliosis, as well as the increased oxidative stress elicited by the amyloid deposits. MT-III, in contrast, remained essentially unaltered, which agrees with some but not all studies, of AD. In situ hybridization results in a transgenic mouse model of AD amyloid deposits, the Tg2576 mouse, which expresses human Abeta precursor protein harboring the Swedish K670N/M671L mutations, are in accordance with results in human brains. Overall, these and other studies strongly suggest specific roles for MT-I, MT-II, and MT-III in brain physiology.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Inflamação/metabolismo , Metalotioneína/metabolismo , Modelos Animais , Animais , Encéfalo/patologia , Humanos , Hibridização In Situ , Masculino , Metalotioneína/genética , Camundongos , Estresse Oxidativo , RNA Mensageiro/genética
20.
FASEB J ; 17(14): 2166-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12958150

RESUMO

Interleukin-6 (IL-6) is produced by many different cell types. Human skeletal muscles produce and release high amounts of IL-6 during exercise; however, the cell source of origin in the muscle is not known. Therefore, we studied the protein expression of IL-6 by immunohistochemistry in human muscle tissue from biopsies obtained at time points 0, 3, 4.5, 6, 9, and 24 h in relation to 3 h of bicycle exercise performed by healthy young males (n=12) and in resting controls (n=6). The IL-6 expression was clearly increased after exercise and remained high even by 24 h, relative to pre-exercise or resting individuals. The IL-6 immunostainings of skeletal muscle cells were homogeneous and without difference between muscle fiber types. The IL-6 mRNA peaked immediately after the exercise, and, in accordance, the IL-6 protein expression within muscle cells was most pronounced around 3 h post-exercise. However, the finding that plasma IL-6 concentration peaked in the end of exercise indicates a high turnover of muscle-derived IL-6. In conclusion, the finding of marked IL-6 protein expression exclusively within skeletal muscle fibers following exercise demonstrates that skeletal muscle fibers of all types are the dominant cell source of exercise-induced release of IL-6 from working muscle.


Assuntos
Exercício Físico , Interleucina-6/análise , Fibras Musculares Esqueléticas/química , Músculo Esquelético/química , Humanos , Imuno-Histoquímica , Interleucina-6/genética , Interleucina-6/imunologia , Masculino , Modelos Biológicos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismo , RNA Mensageiro/metabolismo
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