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1.
Biochem Pharmacol ; 189: 114396, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33359364

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, with a poor 5-year survival rate of approximately 6%, mostly due to poor treatment response and early progression. The S100 gene family participates in various pathophysiological processes in various malignancies. S100A16 is a member of the S100 family, which is abnormally expressed in PDAC; however, its biological functions and mechanisms of action remain unclear. We analysed the Gene Expression Omnibus (GEO) public database and the gene ChIP data collected in our previous study of human PDAC cell line PANC-1 cocultured with M2 macrophages to identify differentially expressed genes (DEGs). Twenty-three overexpressed genes were identified by screening. Then, the selected genes were analysed using The Cancer Genome Atlas (TCGA) database to assess whether they have significant impact on the overall survival (OS) of PDAC patients. Of the 14 DEGs identified, S100A16 was associated with poor prognosis and was selected for further investigation; the results indicate that S100A16 is positively correlated with epithelial-mesenchymal transition (EMT)-related genes in the TCGA dataset. Subsequent in vitro and in vivo experiments demonstrated that S100A16 induces the EMT to promote the metastasis of human PDAC cells and that the effect is mediated by the enhanced expression of TWIST1 and activation of the STAT3 signalling pathway. The antitumour effect of gemcitabine (GEM) was enhanced in combination with S100A16 downregulation. In conclusion, our findings suggest that S100A16 is a novel potential therapeutic target for human PDAC treatment.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Carcinoma Ductal Pancreático/metabolismo , Desoxicitidina/análogos & derivados , Transição Epitelial-Mesenquimal/fisiologia , Neoplasias Pancreáticas/metabolismo , Proteínas S100/administração & dosagem , Proteínas S100/biossíntese , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Técnicas de Cocultura , Terapia Combinada/métodos , Desoxicitidina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Marcação de Genes/métodos , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Proteínas S100/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Gencitabina
2.
Fish Shellfish Immunol ; 92: 480-488, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207301

RESUMO

Antibacterial peptides (AMPs) are expected to replace some or all of the antibiotics and become a new feed additive. However, the high production cost and unclear mechanism limited the application of AMPs. In this research, the effects of a commercial polypeptide (Polypeptide S100) whose main components are AMPs on the growth, antibacterial immune and intestinal microbial of Litopenaeus vannamei were study. L. vannamei (initial weight of 0.16 ±â€¯0.03 g) were fed for 123 days with basal diet added Polypeptide S100 at two levels each (0.5% and 1%) as experimental groups, and a basal diet as control. Dietary inclusion of Polypeptide S100 at 1% level significantly increased the weight gain (WG) and specific growth rate (SGR) of L. vannamei. The survival rates of L. vannamei in 0.5% and 1% Polypeptide S100 groups were significantly higher than the control when infected by Vibrio harveyi but not Vibrio parahaemolyticus. The activities of total superoxide dismutase (T-SOD) and lysozyme (LZM) in the two experimental groups were all significantly higher than the control. Differently, the activities of amylase (AMS) and lipase (LPS) were significantly higher in 0.5% Polypeptide S100 group but lower in 1.0% Polypeptide S100 group. Illumina MiSeq high-throughput sequencing showed that the dominant phyla in the intestine of L. vannamei were Proteobacteria, followed by Actinobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Fusobacteria and Tenericutes, and the abundance of predominant phyla Cyanobacteria were upregulated significantly in the experimental groups. At the family level, significant increase was observed in Pseudomonadaceae and Xanthomonadaceae but decrease in Vibrionaceae in the 1.0% Polypeptide S100 group. The abundance of predominant genus Photobacterium were obviously downregulated in the two experimental groups. Unlikely, the abundance of Pseudomonas and Stenotrophomonas were distinctly increased in the 1.0% Polypeptide S100 group but not significantly different from the control in 0.5% Polypeptide S100 group. All these results suggested that Polypeptide S100 could improve the growth performance, antibacterial immune and intestinal microbiota structure of L. vannamei.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Penaeidae/efeitos dos fármacos , Penaeidae/imunologia , Peptídeos/metabolismo , Proteínas S100/metabolismo , Ração Animal/análise , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Dieta , Suplementos Nutricionais/análise , Penaeidae/crescimento & desenvolvimento , Penaeidae/microbiologia , Peptídeos/administração & dosagem , Proteínas S100/administração & dosagem
3.
Cell Rep ; 25(11): 3074-3085.e5, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30540940

RESUMO

Intratumoral (IT) STING activation results in tumor regression in preclinical models, yet factors dictating the balance between innate and adaptive anti-tumor immunity are unclear. Here, clinical candidate STING agonist ADU-S100 (S100) is used in an IT dosing regimen optimized for adaptive immunity to uncover requirements for a T cell-driven response compatible with checkpoint inhibitors (CPIs). In contrast to high-dose tumor ablative regimens that result in systemic S100 distribution, low-dose immunogenic regimens induce local activation of tumor-specific CD8+ effector T cells that are responsible for durable anti-tumor immunity and can be enhanced with CPIs. Both hematopoietic cell STING expression and signaling through IFNAR are required for tumor-specific T cell activation, and in the context of optimized T cell responses, TNFα is dispensable for tumor control. In a poorly immunogenic model, S100 combined with CPIs generates a survival benefit and durable protection. These results provide fundamental mechanistic insights into STING-induced anti-tumor immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunidade , Proteínas de Membrana/metabolismo , Neoplasias/imunologia , Animais , Antígeno CTLA-4/metabolismo , Linhagem Celular Tumoral , Citocinas/metabolismo , Relação Dose-Resposta Imunológica , Resistencia a Medicamentos Antineoplásicos , Hematopoese , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/patologia , Receptor de Morte Celular Programada 1/metabolismo , Proteínas S100/administração & dosagem , Proteínas S100/imunologia
4.
Cell Death Dis ; 9(6): 657, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844306

RESUMO

The subcellular location of annexin A1 (ANXA1) determines the ultimate fate of neurons after ischemic stroke. ANXA1 nuclear translocation is involved in neuronal apoptosis after cerebral ischemia, and extracellular ANXA1 is also associated with regulation of inflammatory responses. As the factors and mechanism that influence ANXA1 subcellular translocation remain unclear, studies aiming to determine and clarify the role of ANXA1 as a cell fate 'regulator' within cells are critically needed. In this study, we found that intracerebroventricular injection of the recombinant adenovirus vector Ad-S100A11 (carrying S100A11) strongly improved cognitive function and induced robust neuroprotective effects after ischemic stroke in vivo. Furthermore, upregulation of S100A11 protected against neuronal apoptosis induced by oxygen-glucose deprivation and reoxygenation (OGD/R) in vitro. Surprisingly, S100A11 overexpression markedly decreased ANXA1 nuclear translocation and subsequently alleviated OGD/R-induced neuronal apoptosis. Notably, S100A11 exerted its neuroprotective effect by directly binding ANXA1. Importantly, S100A11 directly interacted with ANXA1 through the nuclear translocation signal (NTS) of ANXA1, which is essential for ANXA1 to import into the nucleus. Consistent with our previous studies, ANXA1 nuclear translocation after OGD/R promoted p53 transcriptional activity, induced mRNA expression of the pro-apoptotic Bid gene, and activated the caspase-3 apoptotic pathway, which was almost completely reversed by S100A11 overexpression. Thus, S100A11 protects against cell apoptosis by inhibiting OGD/R-induced ANXA1 nuclear translocation. This study provides a novel mechanism whereby S100A11 protects against neuronal cells apoptosis, suggesting the potential for a previously unidentified treatment strategy in minimizing apoptosis after ischemic stroke.


Assuntos
Anexina A1/metabolismo , Apoptose , Isquemia Encefálica/terapia , Núcleo Celular/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Proteínas S100/uso terapêutico , Animais , Comportamento Animal/efeitos dos fármacos , Isquemia Encefálica/complicações , Isquemia Encefálica/fisiopatologia , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glucose/deficiência , Masculino , Proteínas de Membrana/metabolismo , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Atividade Motora/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oxigênio , Ligação Proteica , Transporte Proteico , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/fisiopatologia , Proteínas Repressoras/metabolismo , Proteínas S100/administração & dosagem , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia
5.
An. pediatr. (2003. Ed. impr.) ; 84(5): 254-259, mayo 2016. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-151592

RESUMO

INTRODUCCIÓN: La proteína S100β se ha propuesto como posible biomarcador en patología neurológica, tanto crónica como aguda. Los valores normales de esta proteína están bien definidos en adultos, no así en niños, en los que los valores séricos parecen variar con la edad. Nuestro objetivo es describir valores de referencia de S100β sérica en niños de 0 a 14 años. MATERIAL Y MÉTODOS: Estudio prospectivo en 257 niños sanos. Se establecieron 3 grupos por edad (menores de 12 meses, de 12 a 24 meses y mayores de 24 meses). RESULTADOS: Se incluyó a 179 niños y 78 niñas. La edad media ± DE fue de 5,5 ± 3,75 años. La concentración sérica media de la proteína S100β en todo el grupo fue 0,156 (0,140-0,172) μg/l. En los menores de 12 meses, la concentración sérica de S100β fue de 0,350 (0,280-0,421) μg/l; 0,165 (0,139-0,190) μg/l en el grupo entre 12 y 24 meses y 0,121 (0,109-0,133) μg/l en el grupo de niños mayores de 24 meses. Se observó una relación inversa entre la edad y la concentración sérica de S100β, que desciende conforme se incrementa la edad. No se observaron diferencias en cuanto al sexo. CONCLUSIONES: La concentración de S100β permanece estable a partir de los 2 años de edad, siendo posible establecer unos valores de referencia de S100β para mayores de 2 años. En los 2 primeros años de vida, la concentración de S100β sérica es más elevada cuanto menor es la edad del niño. No se observan diferencias en el valor de S100β sérica entre ambos sexos


INTRODUCTION: S100β protein has been proposed as a potential biomarker for both chronic and acute neurological disorders. Reference values of this protein are well defined in adults but not in children, in whom serum levels appear to vary with age. Reference values for serum S100β in children from 0 to 14 years are presented. MATERIALS AND METHODS: A prospective study was conducted on 257 healthy children, who were divided into three age groups (under 12 months, 12 to 24 months and over 24 months). RESULTS: The study included179 boys and 78 girls, with a mean age of 5.5 (3.75) years. The mean serum concentration of protein S100β was 0.156 (0.140-0.172) μg/l. In children under 12 months, serum S100β concentration was 0.350 (0.280-0.421) μg/l; 0.165 (0.139-0.190) μg/l in the group between 12 and 24 months and 0.121 (0.109-0.133) μg/l in children older than 24 months. An inverse relationship was observed between age and serum S100β, which declines as age increases. No differences were observed between sexes. CONCLUSIONS: The concentration of S100β remains stable after two years of age, being possible to establish a baseline of S100β for over two years. During the first two years of life, S100β serum concentration is higher, the lower the age of the child. No differences in serum S100β levels between sexes are observed


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Proteínas S100/administração & dosagem , Proteínas S100/farmacologia , Proteínas S100/uso terapêutico , Biomarcadores/análise , Biomarcadores/metabolismo , Pediatria/instrumentação , Pediatria/métodos , Diagnóstico Clínico , Valores de Referência , Proteínas Sanguíneas/farmacologia , Proteínas Sanguíneas/uso terapêutico , Estudos Prospectivos , Epidemiologia Descritiva , Espanha
6.
Plast Reconstr Surg ; 123(6): 1688-1696, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19483567

RESUMO

BACKGROUND: Immunological demyelination is a proposed strategy to improve nerve regeneration in the peripheral nervous system. To investigate the remyelinating potential of Schwann cells in vivo in the peripheral nervous system, the authors have reproduced and expanded upon a novel model of immunological demyelination in the adult rat sciatic nerve. The authors demonstrate (1) the peripheral nervous system's quantitative, regenerative response to immunological demyelination and (2) whether Schwann cells within a region of demyelination are induced to divide in the presence of demyelinated axons. METHODS: The sciatic nerves of female Sprague-Dawley rats were exposed and injected with demyelinating agent bilaterally. At 3 days (n = 3), 7 days (n = 3), and 14 days (n = 3), the animals were euthanized for histological evaluation. A second group of animals (n = 3) was similarly injected with demyelinating agent and then exposed to bromodeoxyuridine between 48 and 72 hours after the onset of demyelination. These animals were euthanized soon after the last injection of bromodeoxyuridine. The tissue was analyzed for Schwann cells (labeled with antibodies to S100) and bromodeoxyuridine assay. RESULTS: A single epineural injection of complement proteins plus antibodies to galactocerebroside resulted in demyelination followed by Schwann cell remyelination. At 3 days after injection, peripheral nerve demyelination and Schwann cell proliferation were evident. Maximum demyelination was seen at 7 days; however, Schwann cell proliferation and remyelination peaked at 14 days after injection. CONCLUSIONS: These studies demonstrate an immunological model of demyelination and remyelination in the peripheral nervous system and quantitatively measure regenerative potential. This model will be used to isolate nerve segments and to measure their regenerative potential when given demyelinating agent after acute contusion and transection injuries.


Assuntos
Antimetabólitos/efeitos adversos , Bromodesoxiuridina/efeitos adversos , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/terapia , Bainha de Mielina/fisiologia , Regeneração Nervosa/fisiologia , Sistema Nervoso Periférico/fisiologia , Regeneração/fisiologia , Proteínas S100/uso terapêutico , Nervo Isquiático/efeitos dos fármacos , Animais , Antimetabólitos/administração & dosagem , Bromodesoxiuridina/administração & dosagem , Movimento Celular , Doenças Desmielinizantes/patologia , Feminino , Ratos , Ratos Sprague-Dawley , Proteínas S100/administração & dosagem , Células de Schwann/efeitos dos fármacos , Células de Schwann/patologia
7.
Vestn Oftalmol ; 125(2): 3-7, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19517821

RESUMO

The effects of two 5-membered (SP5, SP6) endogenous synthetic peptide fragments of protein S100b on the course of regenerative-reparative processes in the corneas of Wistar rats were morphologically studied after making a graduated injury. Conjunctival or endonasal injection of the peptides was made at two concentrations of 10(-6) and 10(-8) M. The study peptides were found to have a modulating effect on regenerative-reparative processes regardless of the route of administration and to induce accelerated and qualitative corneal wound healing as compared with the controls. The specific feature of SP5 was the formation of a fibroblastic membrane. When SP5 was injected at a concentration of 10(-6) M, the membrane was more pronounced and occupied the whole area of keratectomy whereas when this peptide was administered at a concentration of 10(-8) M, its formation was observed in the deep and middle corneal layers. The most marked effect of SP6 revealed during the study was the formation of newly-formed vessels over the entire wound surface independently of the concentration of the injected substance. Of the two study peptide fragments, SP5 is, in the authors' opinion, promising for clinical application. Significant keratocytic proliferation noted in the use of SP5 at a concentration of 10(-6) M may be used to accelerate scarring when the sclera and cutaneous covering are damaged. The effects detected with administration of SP6 at two concentrations were regarded as negative as they did not answer the purpose set during the study performed.


Assuntos
Córnea/fisiologia , Doenças da Córnea/fisiopatologia , Fatores de Crescimento Neural/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Regeneração/fisiologia , Proteínas S100/administração & dosagem , Animais , Autoantígenos , Doenças da Córnea/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Soluções Oftálmicas , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100 , Resultado do Tratamento
8.
Bull Exp Biol Med ; 146(2): 172-5, 2008 Aug.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-19145309

RESUMO

We compared activity of synthetic complexes of angiotensin II and functionally different proteins (transport protein, serum albumin and neurospecific Ca2+-binding protein S100b) as analogues of endogenous protein-peptide complexes. Physiological activity of angiotensin II was specifically modified by these proteins. It was hypothesized that the complex of angiotensin II and S100b is primarily involved in the regulation of hemodynamics, whereas the complex of angiotensin II and bovine serum albumin plays a role in the formation and realization of drinking behavior.


Assuntos
Angiotensina II/metabolismo , Proteínas de Transporte/metabolismo , Comportamento de Ingestão de Líquido/fisiologia , Hemodinâmica/fisiologia , Fatores de Crescimento Neural/metabolismo , Proteínas S100/metabolismo , Soroalbumina Bovina/metabolismo , Angiotensina II/administração & dosagem , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Captopril/farmacologia , Proteínas de Transporte/administração & dosagem , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Hemodinâmica/efeitos dos fármacos , Masculino , Fatores de Crescimento Neural/administração & dosagem , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/administração & dosagem , Saralasina/farmacologia , Soroalbumina Bovina/administração & dosagem
9.
Biochem Biophys Res Commun ; 343(2): 555-63, 2006 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-16554030

RESUMO

Cardiomyogenesis is influenced by factors secreted by anterior-lateral and extra-embryonic endoderm. Differentiation of embryonic stem cells in embryoid bodies allows to study the influence of growth factors on cardiomyogenesis. By these means SPARC was identified as a new factor enhancing cardiomyogenesis [M. Stary, W. Pasteiner, A. Summer, A. Hrdina, A. Eger, G. Weitzer, Parietal endoderm secreted SPARC promotes early cardiomyogenesis in vitro, Exp. Cell Res. 310 (2005) 331-341]. Here we report a similar and new function for S100A4, a calcium-binding protein of the EF-hand type. S100A4 is secreted by parietal endoderm and promotes early differentiation and proliferation of cardiomyocytes. Oligomeric S100A4 supports cardiomyogenesis in a concentration-dependent manner, whereas inhibition of autocrine S100A4 severely attenuates cardiomyogenesis. S100A4 specifically influences transcription in differentiating cardiomyocytes, as evident from increased expression of cardiac transcription factor genes nkx2.5 and mef2C. These data suggest that S100A4, like SPARC, plays a supportive role in early in vitro cardiomyogenesis.


Assuntos
Embrião de Mamíferos/citologia , Embrião de Mamíferos/fisiologia , Endoderma/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Proteínas S100/administração & dosagem , Proteínas S100/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células , Relação Dose-Resposta a Droga , Embrião de Mamíferos/efeitos dos fármacos , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/metabolismo , Humanos , Proteínas de Domínio MADS/metabolismo , Fatores de Transcrição MEF2 , Miócitos Cardíacos/efeitos dos fármacos , Fatores de Regulação Miogênica/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100 , Fatores de Transcrição/metabolismo
10.
J Neurochem ; 91(6): 1284-91, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15584905

RESUMO

S100B protein in brain is produced primarily by astrocytes, has been used as a marker for brain injury and has also been shown to be neurotrophic and neuroprotective. Using a well characterized in vitro model of brain cell trauma, we examined the potential role of exogenous S100B in preventing delayed neuronal injury. Neuronal plus glial cultures were grown on a deformable Silastic membrane and then subjected to strain (stretch) injury produced by a 50 ms displacement of the membrane. We have previously shown that this injury causes an immediate, but transient, nuclear uptake of the fluorescent dye propidium iodide by astrocytes and a 24-48 h delayed uptake by neurons. Strain injury caused immediate release of S100-beta with further release by 24 and 48 h. Adding 10 or 100 nm S100B to injured cultures at 15 s, 6 h or 24 h after injury reduced delayed neuronal injury measured at 48 h. Exogenous S100B was present in the cultures through 48 h. These studies directly demonstrate the release and neuroprotective role of S100B after traumatic injury and that, unlike most receptor antagonists used for the treatment of trauma, S100B is neuroprotective when given at later, more therapeutically relevant time points.


Assuntos
Fatores de Crescimento Neural/metabolismo , Neurônios/metabolismo , Fármacos Neuroprotetores/metabolismo , Proteínas S100/metabolismo , Animais , Contagem de Células , Células Cultivadas , Técnicas de Cocultura , Esquema de Medicação , Fatores de Crescimento Neural/administração & dosagem , Fatores de Crescimento Neural/farmacocinética , Fatores de Crescimento Neural/farmacologia , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacocinética , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/administração & dosagem , Proteínas S100/farmacocinética , Proteínas S100/farmacologia , Estresse Mecânico , Fatores de Tempo
11.
J Neurotrauma ; 21(5): 541-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15165362

RESUMO

Elevated serum S100B levels have been shown to be a predictor of poor outcome after traumatic brain injury (TBI). Experimental data, on the other hand, demonstrate a neuroprotective and neurotrophic effect of this calcium-binding protein. The purpose of this study was to examine the role of increased S100B levels on functional outcome after TBI. Following lateral fluid percussion or sham injury in male Sprague Dawley rats (n = 56), we infused S100B (50 ng/h) or vehicle into the cerebrospinal fluid of the ipsilateral ventricle for 7 days using an osmotic mini-pump. Assessment of cognitive performance by the Morris water maze on days 30-34 after injury revealed an improved performance of injured animals after S100B infusion (p < 0.05), when compared to vehicle infusion. Blood samples for analysis of clinical markers of brain damage, S100B and neuron specific enolase, taken at 30 min, 3 h, 4 h, 2 days, or 5 days showed a typical peak 3 h after injury (p < 0.01), and higher serum levels correlated significantly with an impaired cognitive recovery (p < 0.01). The correlation of higher serum S100B levels with poor water maze performance may result from injury induced opening of the blood-brain barrier, allowing the passage of S100B into serum. Thus while higher serum levels of S100B seem to reflect the degree of blood-brain barrier opening and severity of injury, a beneficial effect of intraventricular S100B administration on long-term functional recovery after TBI has been demonstrated for the first time. The exact mechanism by which S100B exerts its neuroprotective or neurotrophic influence remains unknown and needs to be elucidated by further investigation.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Cognição/efeitos dos fármacos , Fatores de Crescimento Neural/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Proteínas S100/administração & dosagem , Animais , Lesões Encefálicas/sangue , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Fatores de Crescimento Neural/sangue , Fosfopiruvato Hidratase/sangue , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/sangue
12.
Physiol Behav ; 71(1-2): 29-33, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11134682

RESUMO

Adult male Wistar rats were bilaterally implanted with indwelling cannulae in the hippocampus. Forty-eight hours after surgery, animals were habituated to an open-field box during 2 min, being tested 24 h later; next they were trained in a step-down inhibitory avoidance task (3.0 s, 0.4 mA foot-shock), being tested again 24 h later. Immediately after the training session of each task, animals received a 0.5-microl infusion of calcium-phosphate-buffered saline (PBS) and S100B (20, 200, 2000, or 20,000 nM). In the inhibitory avoidance task, animals infused with the two highest concentrations of S100B, 2 and 20 microM, obtained higher scores of retention relative to controls in the test session (p<0.05), and a trend toward an increase was observed in animals infused with 200 nM (p<0. 10). In both sessions of the habituation task, groups were not different regarding crossings, rearings, and time for leaving the first square (p>0.10). These results indicate that, in rats, post-training increased hippocampal levels of S100B right after training facilitate, in a dose-dependent way, long-term memory for an inhibitory avoidance task, but not for an open-field habituation.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/farmacologia , Habituação Psicofisiológica/efeitos dos fármacos , Hipocampo/fisiologia , Memória/efeitos dos fármacos , Proteínas S100/farmacologia , Animais , Proteínas de Ligação ao Cálcio/administração & dosagem , Relação Dose-Resposta a Droga , Injeções , Masculino , Fatores de Crescimento Neural , Ratos , Ratos Wistar , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/administração & dosagem
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