Stroke is one of the main causes of death and disability worldwide. The great impact on the quality of life of the population and on the health system justifies that we seek relevant alternatives to ...reduce the incidence and improve the treatment and recovery of patients affected by this disease. Physical exercise appears as an important tool in this scenario, being already pointed out as a possible therapeutic approach for the prevention of non-contagious chronic diseases. In this context, biomarkers such as miRNAs that respond to physical exercise and are directly related to several epigenetic mechanisms appear. Therefore, explaining the molecular mechanisms involved during physical exercise will lead to a better understanding of each stimulus and the dose to be used to better respond to each situation, thus being a promising approach for the evolution of prescription and control of training and processes recovery from various diseases, including stroke. Forty-eight Wistar rats were used, divided into four experimental groups: control group, ischemia group, physical exercise group and exercise + ischemia group. Real-time PCR methodology was used to analyze the expression of miRNAs: miR-126, miR-133b and miR-221. In our study we observed a significant difference in the expression of miR- 221 between the control group and the others groups. However, microRNAs: miR-126 and miR-133b do not show significant differences in expression between groups.
This study aimed to investigate the morphometric and the pattern of protein and gene expression related to the extrinsic apoptotic pathway in experimental focal cerebral ischemia and the hole of ...neuroprotection with hypothermia and ketoprofen. For this analysis, 120 rats were randomly divided into 3 groups (20 animals each): control - no surgery (20 animals); sham - simulation of surgery (20 animals); ischemic - focal ischemia for 1 hour, without reperfusion (80 animals) and divided into four subgroups with 20 animals each: ischemic + intraischemic hypothermia; ischemic + previous intravenous ketoprofen, and ischemic + hypothermia and ketoprofen. The infarct volume was measured using morphometric analysis of infarct areas defined by triphenyl tetrazolium chloride and the patterns of expression of the apoptosis genes (Fas, c-Flip, caspase-8 and caspase-3) and the apoptosis protein caspase-3 were evaluated by quantitative real-time PCR and immunohistochemistry, respectively. Hypo expression of genes of extrinsic pathway of apoptosis was observed: Fas receptor, c-Flip and caspase-8 in the ischemics areas. Increases in the gene and protein caspase-3 in the ischemic areas were also observed, and these increases were reduced by hypothermia and ketoprofen, also noted in the morphometric study. The caspases-3 increase suggests that this gene plays an important role in apoptosis, probably culminating in cell death and that the neuroprotective effect of hypothermia and ketoprofen is involved. KEY WORDS: Apoptosis; Gene expression; Caspase-3; Cerebral ischemia; Neuroprotection; Hypothermia; Ketoprofen.
The chronic consumption of alcohol causes a worsening of the events that follow the cerebral ischemia. These events are regulated through the expression of several genes and microRNAs. The aimof this ...work was To analyze and describe the expression profile of PARP and AIF and miRNA-9 proteins in rats submitted to focal cerebral ischemia, associated or not with chronic alcoholism model. Methods: Twenty adult Wistar rats, subdivided into: control; ischemic; alcoholic and ischemic / alcoholized for immunohistochemical analysis and miRNA-9 gene expression. Results: There was a reduction in the protein expression of PARP-1 and a positive marking for AIF in the ischemic / alcoholized group. The miRNA-9 did not obtain significant expression. The association of ischemia with chronic alcohol use promoted a tendency to low expression of miRNA-9, low expression of PARP-1 and high expression of AIF, indicating an interference in the protective effect of miRNA-9 be observed in the other groups. KEY WORDS: PARP-1; AIF; miRNA-9; Cerebral ischemia; Alcoholism.
INTRODUÇÃO: A isquemia cerebral é uma das principais causas de morte no Brasil, segundo levantamento da Sociedade Brasileira de Neurologia em 2000, sendo a terceira causa de morte após doenças ...cardiovasculares e o câncer, além de ser uma das maiores causas de sequela permanente capaz de gerar incapacidade. Nas últimas décadas, estudos experimentais tem demonstrado efeitos benéficos do exercício físico associado à isquemia cerebral. Vários mecanismos moleculares estão envolvidos na fisiopatologia da isquemia cerebral, entre eles as alterações nos perfis de expressão de neurotransmissores. Pesquisas atuais também destacam o papel dos microRNAs na isquemia cerebral quanto na regulação dos neurotransmissores. Portanto, analisar a expressão de neurotransmissores e microRNAs associados à isquemia cerebral, assim como o papel dos benefícios promovidos pelo exercício físico poderá contribuir na elucidação de possíveis vias moleculares com efeito neuroprotetor. MATERIAIS E MÉTODOS: Foram utilizados 48 animais divididos em quatro grupos experimentais: controle, submetido à isquemia cerebral, submetido ao exercício físico e submetido ao exercício físico associado à isquemia cerebral. A metodologia de PCR em tempo real foi utilizada para analisar a expressão dos miRNAs; miR15b, miR29b, miR-219 e miR-222. RESULTADOS E CONCLUSÃO: não observamos diferenças estatísticas significativas na expressão dos miRNAs miR-15b, miR- 12 29b, miR-219 e miR-222 no tecido cerebral dos grupos submetidos à isquemia cerebral, submetidos ao exercício físico e na associação dos dois grupos quando comparados ao grupo controle. Entretanto, os miRNAs miR-15b e miR222 apresentaram maior expressão no grupo com a associação da isquemia cerebral e exercício físico
INTRODUCTION: Cerebral ischemia is one of the main causes of death in Brazil, according to a survey by the Brazilian Society of Neurology in 2000, being the third cause of death after cardiovascular diseases and cancer, besides being one of the major causes of permanent sequela capable of generate disability. In the last decades, experimental studies have shown beneficial effects of physical exercise associated with cerebral ischemia. Several molecular mechanisms are involved in the pathophysiology of cerebral ischemia, including changes in neurotransmitter expression profiles. Current research also highlights the role of microRNAs both in the process of cerebral ischemia and in the regulation of neurotransmitters. Therefore, analyzing the expression of neurotransmitters and microRNAs associated with cerebral ischemia, as well as the role of the benefits promoted by physical exercise may contribute to the elucidation of possible molecular pathways with neuroprotective effect. MATERIALS AND METHODS: 48 animals were divided into 4 experimental groups: control, cerebral ischemia, physical exercise and physical exercise associated with cerebral ischemia. The real-time PCR methodology was used to analyze miRNA expression: miR15b, miR-29b, miR219 and miR-222. RESULTS AND CONCLUSION: We did not observe statistically significant differences in the miRNA expression of miRNAs: miR 15b, miR-29b, miR-219 and miR-222 in brain tissue groups submitted to 15 cerebral ischemia, physical exercise and in the association of the two groups when compared to the group control. However, the miR-15b and miR-222 levels of expression increased in the group of cerebral ischemia associated with physical exercise