7 research outputs found
Characterization and modulation of microglial phenotypes in an animal model of severe sepsis
Get PDFWe aim to characterize the kinetics of early and late microglial phenotypes after systemic inflammation in an animal model of severe sepsis and the effects of minocycline on these phenotypes. Rats were subjected to CLP, and some animals were treated with minocycline (10 ug/kg) by i.c.v. administration. Animals were killed 24 hours, 5, 10 and 30 days after sepsis induction, and serum and hippocampus were collected for subsequent analyses. Real-time PCR was performed for M1 and M2 markers. TNF-α, IL-1β, IL-6, IL-10, CCL-22 and nitrite/nitrate levels were measured. Immunofluorescence for IBA-1, CD11b and arginase was also performed. We demonstrated that early after sepsis, there was a preponderant up-regulation of M1 markers, and this was not switched to M2 phenotype markers later on. We found that up-regulation of both M1 and M2 markers co-existed up to 30 days after sepsis induction. In addition, minocycline induced a down-regulation, predominantly, of M1 markers. Our results suggest early activation of M1 microglia that is followed by an overlap of both M1 and M2 phenotypes and that the beneficial effects of minocycline on sepsis-associated brain dysfunction may be related to its effects predominantly on the M1 phenotype
Caracterização dos fenótipos microgliais na sepse e sua modulação fenotípica com minociclina
No full textArtigo apresentado como requisito parcial para obtenção do grau de Bacharel, no Curso de Medicina, da Universidade do Extremo Sul Catarinense- UNESCCom as taxas de mortalidade decorrentes de sepse em declínio, as sequelas causadas pelos seus mecanismos patológicos tornam-se cada vez mais relevantes no contexto clínico dos sobreviventes. A estratégia de modulação fenotípica M1/M2 da microglia neuronal parece promissora em reduzir os danos neuroinflamatórios implicados nesta disfunção orgânica. O estudo analisou o uso do antibiótico minociclina e sua interferência em níveis de marcadores microgliais como possível alternativa na regulação da expressão dos fenótipos pró-inflamatórios ou anti-inflamatórios. Utilizou-se um modelo animal de sepse em ratos machos wistar, induzida através da técnica de ligação e perfuração cecal (CLP), os animais foram divididos em dois subgrupos, os submetidos a CLP e tratados com minociclina e os submetidos a CLP e não tratados com minociclina, por administração em dose única intracerebroventricular de 100μg/kg de minociclina ou de soro fisiológico 0,9%. Os ratos foram mortos imediatamente após o procedimento CLP ou 24 horas, 3, 5, 10 e 30 dias após a cirurgia e seu hipocampo fora removido e analisado bioquimicamente por marcadores de CD11, CD16, CD32, CD206, CCL22, IL1, IL6, IL10, iNOS, TNF-α, TGF, Arginase e Nitrito/Nitrato. Comparamos os grupos através da análise de variância (ANOVA) de duas vias seguido pelo tesde de post-hoc de Tukey. A minociclina atuou, de maneira geral, reduzindo significativamente a expressão dos marcadores e citocinas de microglia M1 – descrita como pró-inflamatória e indutora dano neuronal - no hipocampo dos ratos submetidos a sepse, sem suprimir os marcadores de migroglial M2 – considerada anti-inflamatória, imunoreguladora e imunossupressora – através da análise por RT-qPCR, razão de nitrito e nitrato, método ELISA sanduíche ou ainda por imuno-histoquímica. Esse achado, associado ao conhecimento da neurotoxicidade de fatores pró inflamatórios ao SNC, aventa a possibilidade de eventuais abordagens terapêuticas afim de se reduzir o comprometimento neuronal nos sobreviventes de sepse
Characterization and modulation of microglial phenotypes in an animal model of severe sepsis
Get PDFWe aim to characterize the kinetics of early and late microglial phenotypes after systemic inflammation in an animal model of severe sepsis and the effects of minocycline on these phenotypes. Rats were subjected to CLP, and some animals were treated with minocycline (10 ug/kg) by i.c.v. administration. Animals were killed 24 hours, 5, 10 and 30 days after sepsis induction, and serum and hippocampus were collected for subsequent analyses. Real-time PCR was performed for M1 and M2 markers. TNF-α, IL-1β, IL-6, IL-10, CCL-22 and nitrite/nitrate levels were measured. Immunofluorescence for IBA-1, CD11b and arginase was also performed. We demonstrated that early after sepsis, there was a preponderant up-regulation of M1 markers, and this was not switched to M2 phenotype markers later on. We found that up-regulation of both M1 and M2 markers co-existed up to 30 days after sepsis induction. In addition, minocycline induced a down-regulation, predominantly, of M1 markers. Our results suggest early activation of M1 microglia that is followed by an overlap of both M1 and M2 phenotypes and that the beneficial effects of minocycline on sepsis-associated brain dysfunction may be related to its effects predominantly on the M1 phenotype
