mRNA Expression and Methylation of the RAD51, ATM, ATR, BRCA1, and BRCA2 Genes in Gastric Adenocarcinoma.

Background: Immunohistochemical prognostic significance of the homologous recombination-related proteins RAD51, ATM, BRCA1, and BRCA2 is known in gastric adenocarcinoma, one of the deadliest cancers. Objective and design: This retrospective cohort study aimed to evaluate mRNA expression and promoter methylation of some homologous recombination-related genes in this neoplasm. Methods: We evaluated mRNA expression and methylation of RAD51, ATM, ATR, BRCA1, and BRCA2 in tumor and non-tumor frozen samples from gastrectomy specimens by RT-qPCR and MS-HRM, correlating our results with previous immunohistochemistry data and prognostic features. Results: RAD51, ATR, BRCA1, BRCA2, and ATM mRNA expression was detected in 93.75% (45/48), 93.75% (45/48), 91.67% (44/48), 83.33% (40/48), and 89.58% (43/48) of the tumors; partial or complete methylation, in 94.87% (37/39), 0 (0/42), 97.56% (40/41), 100% (41/41), and 0 (0/40), respectively. Most gene pairs showed significant weak to moderate positive correlations of tumoral mRNA expression with each other: RAD51 with ATR (P = .027), BRCA1 (P < .001), and BRCA2 (P < .001); ATR with BRCA1 (P = .007), and ATM (P = .001); BRCA1 with BRCA2 (P = 0.001). BRCA1 mRNA was reduced in tumors compared with non-neoplastic mucosa (0.345 vs 1.272, P = .015) and, excluding neoadjuvant therapy cases, in T3 to T4 tumors compared with T2 (0.414 vs 0.954, P = .035). Greater tumoral RAD51 mRNA levels correlated with perineural invasion (1.822 vs 0.725, P = .010) and death (1.664 vs 0.929, P = .036), but not with survival time. There was an inverse association between nuclear immunohistochemical positivity for ATR and its mRNA levels (0.487 vs 0.907, P = .032), and no significant correlation for the other markers. Conclusions: Our results suggest RAD51, BRCA1, and BRCA2 methylation as a frequent epigenetic mechanism in gastric cancer, support the hypothesis that reduced BRCA1 expression participates in disease progression, and show an association between RAD51 mRNA and perineural invasion and mortality that may be considered unexpected, considering the former immunohistochemical studies. The lack of correlation between immunohistochemistry and mRNA, and even the inverse association, for ATR, can be seen as indicative of action of post-transcriptional or post-translational regulatory mechanisms, to be better investigated.

Expression of microRNAs miR-21 and miR-326 associated with HIF-1α regulation in neurospheres of glioblastoma submitted to ionizing radiation treatment.

Background: Glioblastoma is an incurable neoplasm. Its hypoxia mechanism associated with cancer stem cells (CSCs) demonstrates hypoxia-inducible factor 1α (HIF-1α) expression regulation, which is directly related to tumor malignancy. The aim of this study was to identify a possible tumor malignancy signature associated with regulation of HIF-1α by microRNAs miR-21 and miR-326 in the subpopulation of tumor stem cells which were irradiated by ion in primary culture of patients diagnosed with glioblastoma. Materials and methods: We used cellular cultures from surgery biopsies of ten patients with glioblastoma. MicroRNA expressions were analyzed through real-time polymerase chain reaction (PCR ) and correlated with mortality and recurrence. The ROC curve displayed the cutoff point of the respective microRNAs in relation to the clinical prognosis, separating them by group. Results: The miR-21 addressed high level of expression in the irradiated neurosphere group (p = 0.0028). However, miR-21 was not associated with recurrence and mortality. miR-326 can be associated with tumoral recurrence (p = 0.032) in both groups; every 0.5 units of miR-326 increased the chances of recurrence by 1,024 (2.4%). Conclusion: The high expression of miR-21 in the irradiated group suggests its role in the regulation of HIF-1α and in the radioresistant neurospheres. miR-326 increased the chances of recurrence in both groups, also demonstrating that positive regulation from miR-326 does not depend on ionizing radiation treatment.

Expression of pluripotency-related genes in human glioblastoma.

Background: Cancer is a group of heterogeneous diseases characterized by several disruptions of the genetic and epigenetic components of cell biology. Some types of cancer have been shown to be constituted by a mosaic of cells with variable differentiation states, with more aggressive tumors being more undifferentiated. In most cases, undifferentiated tumor cells express associated embryonic markers such as the OCT4, NANOG, SOX2, and CARM1 genes. The ectopic or reminiscent expression of some master regulator genes of pluripotency has been indicated as the cause of the poorly differentiated state of tumors, and based on the evidence of some reports, can be used as a possible therapeutic target. Considering this information, a more detailed investigation of the expression of pluripotency-associated genes is necessary to evaluate the roles of these genes in the etiology of some tumors and their use targets of therapy. Methods: The expression of four pluripotency-related genes was investigated (OCT4, NANOG, SOX2, and CARM1) in the most malignant primary human brain tumor, glioblastoma (GBM). Results and Conclusion: The results demonstrated a signature of OCT4/SOX2/CARM1 genes and a significant increase of CARM1 expression in GBM cases.

Prognostic Value of the Immunohistochemical Expression of RAD51 and BRCA2 in Gastric Adenocarcinoma.

Current scientific literature lacks data on the prognostic value of the expression of RAD51 and BRCA2 in gastric adenocarcinoma. Therefore, we aimed to evaluate those and other homologous recombination-related proteins (ATM, ATR, BRCA1, CHK2, γH2AX, p53) in gastric cancer, assessing their correlation with clinical prognosis. Paraffin-embedded samples were obtained from surgical specimens collected in total or subtotal gastrectomy procedures. Between 2008 and 2017, 121 patients with advanced gastric adenocarcinoma underwent surgical resection and were included in this study. Negativity for nuclear RAD51 correlated with vascular invasion, lymph node metastasis, larger tumor size, and lower overall survival and disease-free survival in univariate analysis. However, nuclear RAD51-negative cases presented better response rates to adjuvant therapy than the positive ones. Nuclear ATR negativity correlated with larger tumor size and a higher histological grade. Positivity for ATM was associated with more prolonged disease-free survival. Positivity for nuclear BRCA2 correlated with lower overall survival and diffuse histological type, whereas its high expression was associated with vascular invasion. Nevertheless, tumors positive for nuclear BRCA2 were more frequently low grade in the intestinal histological type. Our findings indicate that RAD51 and BRCA2 are valuable immunohistochemical prognostic markers in gastric adenocarcinoma.

Caffeine consumption attenuates ethanol-induced inflammation through the regulation of adenosinergic receptors in the UChB rats cerebellum.

Caffeine consumption is able to interfere in cellular processes related to inflammatory mechanisms by acting through the adenosinergic system. This study aimed to recognize alterations related to adenosinergic system and inflammatory process in the cerebellum of University of Chile Bibulous (UChB) rats after the consumption of ethanol and caffeine. UChB and Wistar rats, males at 5 months old, were divided into the groups (n = 15/group): (i) Control (Wistar rats receiving water); (ii) Ethanol group (UChB rats receiving ethanol solution at 10%) and (iii) Ethanol+caffeine group (UChB rats receiving ethanol solution at 10% added of 3 g/L of caffeine). The cerebellar tissue was collected and processed for immunohistochemistry, Reverse transcription polymerase chain reaction (RT-PCR) and western blotting techniques for the adenosinergic receptors A1 and A2a and inflammatory markers, including Nuclear factor kappa B (NFkB), TLR4, TLR2, MyD88, TNF-α, COX-2, iNOS and microglial marker Iba-1. Results showed ethanol and caffeine consumption differentially altering the immunolocalization of adenosinergic receptors and inflammatory markers in the cerebellar tissue. The A2a receptor was overexpressed in the Ethanol group and was evident in the glial cells. The Ethanol group had increased protein levels for NFκB and TLR4, expressively in Bergmann glia and Purkinje cells. Caffeine reduced the expression of these markers to levels similar to those found in the Control group. The A1 gene was upregulated the Ethanol group, but not its protein levels, suggesting post-transcriptional interference. In conclusion, caffeine seems to attenuate ethanol-induced inflammation in the cerebellum of UChB rats through the A1 and A2a modulation, playing a neuroprotective role in the chronic context of ethanol consumption.

The role of circulating miRNAs and CA19-9 in pancreatic cancer diagnosis.

Diagnosis and treatment of pancreatic ductal adenocarcinoma (PA) remains a challenge in clinical practice. The aim of this study was to assess the role of microRNAs (miRNAs-21, -23a, -100, -107, -181c, -210) in plasma and tissue as possible biomarkers in the diagnosis of PA. Samples of plasma (PAp-n = 13), pancreatic tumors (PAt-n = 18), peritumoral regions (PPT-n = 9) were collected from patients during the surgical procedure. The control group consisted of samples from patients submitted to pancreatic surgery for trauma or cadaveric organs (PC-n = 7) and healthy volunteers donated blood (PCp-n = 6). The expression profile of microRNAs was measured in all groups using RT-PCR, serum CA19-9 levels were determined in PA and PC. In tissue samples, there was a difference in the expression of miRNAs-21, -210 (p < 0.05) across the PAt, PC and PPT groups. The PAp showed overexpression of miRNAs-181c, -210 (p < 0.05) when compared to PCp. The combination of miRNAs-21, -210 tissue expression and serum CA19-9 showed 100% accuracy in the diagnosis of PA, as well as miR-181c expression in the plasma (PApxPCp). The expression of microRNAs in plasma proved to be a promising tool for a noninvasive detection test for PA, as well as further studies will evaluate the utility of microRNAs expression as biomarkers for prognostic and response to therapy in PA.

MicroRNA-27b expression in rats submitted to physical exercise and experimental cerebral ischemia / Expresión de MicroRNA-27b en ratas sometidas a ejercicio físico e isquemia cerebral experimental

SUMMARY: Cerebral ischemia has not only a high mortality rate, which is the second leading cause of death worldwide, but is also responsible for severe disabilities in working age individuals, generating enormous public expending for treatment and rehabilitation of the affected individuals. The role of microRNAs in the pathophysiology of cerebral ischemia has been highlighted in current investigations. In addition, recent studies have also highlighted physical exercise as a possible protective factor both in the prevention and in the effects of cerebral ischemia, placing it as an important study resource. Thus, we investigated the role of physical exercise in experimental cerebral ischemia associated with the expression of microRNA-27b. 16 animals were used, divided into four experimental groups: Control, Physical Exercise, Cerebral Ischemia and Cerebral Ischemia associated with Physical Exercise. The real-time PCR methodology was used to analyze the expression of microRNA-27b. Although there were no statistically significant differences in the expression of microRNA-27b between the groups studied, the increased expression of microRNA-27b in the Physical Exercise group indicates its neuroprotective role in the pathophysiology of cerebral ischemia.

RESUMEN: La isquemia cerebral no solo tiene una alta tasa de mortalidad y es la segunda causa principal de muerte en todo el mundo, sino también es la causa de enfermedades invalidantes en personas en edad laboral, lo que genera un gasto público enorme para el tratamiento y la rehabilitación de las personas afectadas. El papel de los microARN en la fisiopatología de la isquemia cerebral se ha destacado en las investigaciones actuales. Además, estudios recientes también han destacado el ejercicio físico como un posible factor protector tanto en la prevención como en los efectos de la isquemia cerebral, situándolo como un importante recurso de estudio. Por lo tanto, investigamos el papel del ejercicio físico en la isquemia cerebral experimental asociada con la expresión del microARN-27b. Se utilizaron 16 animales, divididos en cuatro grupos experimentales: Control, Ejercicio Físico, Isquemia Cerebral e Isquemia Cerebral asociada al Ejercicio Físico. Se utili- zó la metodología de PCR en tiempo real para analizar la expresión de microARN-27b. Aunque no se observaron diferencias estadísticamente significativas en la expresión de microARN-27b entre los grupos estudiados, la mayor expresión de microARN-27b en el grupo de Ejercicio Físico indica su papel neuroprotector en la fisiopatología de la isquemia cerebral.

Expression of AIF, PARP, and miRNAs MIR-145, MIR-210, and MIR-486 associated with apoptosis in the corpus cavernosum of rats subjected to chronic alcoholism model / Expresión de AIF, PARP y miRNAs MIR-145, MIR-210 y MIR-486 asociados con apoptosis en el cuerpo cavernoso de ratas sometidas a modelo de alcoholismo crónico

SUMMARY: Previous studies from our group described the consequences of using ethanol on penile erection. Nevertheless, the molecular mechanisms surrounding microRNAs, apoptosis process and their relationship with erectile dysfunction associated with alcohol consumption are still poorly understood. The objective of this analysis was to evaluate the mechanism of apoptosis by the expression of AIF and PARP, as well as their regulatory microRNAs: miR-145, miR-210 and miR-486, in the corpus cavernosum of rats submitted to a semivoluntary alcoholism model. For this study 24 Wistar rats were divided into two groups: control (C) and treated with 20 % ethanol (A) for seven weeks. The corpus cavernosum samples were prepared for immunohistochemical analysis of AIF and PARP protein expression, and microRNAs miR-145, miR-210, miR-486 gene expression in cavernous tissue was performed by real time PCR. The immunohistochemical analysis showed little nuclear positive labeling for the protein PARP and AIF in the corpus cavernosum of control and ethanol treated animals. After analysis of miR-145, -210 and -486 microRNA expression in the 12 animals studied, no results were found with significant statistical difference between the control and alcoholized groups. The expression of AIF and PARP and their regulatory microRNAs involved in apoptotic process (miR-145, miR-210 and miR-486) were not altered in the corpus cavernosum of rats submitted to semivoluntary alcoholism.

RESUMEN: Estudios previos de nuestro grupo describieron las consecuencias del uso de etanol en la erección del pene. Sin embargo, los mecanismos moleculares que rodean a los microARN, el proceso de apoptosis y su relación con la disfunción eréctil asociada con el consumo de alcohol aún no se conocen bien. El objetivo de este análisis fue evaluar el mecanismo de apoptosis mediante la expresión de AIF y PARP, así como sus microARN reguladores: miR-145, miR-210 y miR-486, en el cuerpo cavernoso de ratas sometidas a un modelo de alcoholismo semivoluntario. Se dividieron 24 ratas Wistar en dos grupos: control (C) grupo de ratas tratadas con etanol al 20 % (A) durante siete semanas. Las muestras del cuerpo cavernoso se prepararon para el análisis inmunohistoquímico de la expresión de la proteína AIF y PARP, y la expresión del gen microRNAs miR-145, miR-210, miR-486 en tejido cavernoso se realizó por PCR en tiempo real. El análisis inmunohistoquímico mostró escaso etiquetado nuclear positivo para la proteína PARP y AIF en el cuerpo cavernoso de los animales de control y tratados con etanol. Después del análisis de la expresión de microARN miR-145, -210 y -486 no se encontraron resultados con diferencias estadísticas significativas entre los grupos control y alcoholizados. La expresión de AIF y PARP y sus microARN reguladores involucrados en el proceso apoptótico (miR-145, miR-210 y miR-486) no se alteraron en el cuerpo cavernoso de las ratas sometidas a alcoholismo semivoluntario.

Chronic alcoholism associated with diabetes induced apoptosis in the corpus cavernosum of rats.

PURPOSE: To evaluate the effects of alcohol exposure and diabetes on apoptotic process in the corpus cavernosum. METHODS: Forty eight male Wistar rats were divided into four groups: control, diabetic, alcoholic and diabetic-alcoholic. Samples of the corpus cavernosum were prepared to study protein expression of apoptotic genes (Caspases-3 and 9) by immunohistochemistry and Real-Time PCR. RESULTS: The immunoreactivity of Caspases-3 and -9 was diffuse and higher in the treated groups though there was no significant difference between the experimental groups, only when compared with the control group. An increase was observed in the gene expression of Caspases-9 in the diabetic and ethanol-diabetic groups when compared with control and ethanol groups. CONCLUSIONS: The association of these factors (ethanol and diabetes) probably can affect the apoptosis mechanism in lesions of the cavernous tissue in the rat penis. Both gene and protein expression of Caspase-9 in diabetic and ethanol-diabetic groups suggest the involvement of the apoptosis cascade from this study model.

PPARG expression in colorectal cancer and its association with staging and clinical evolution.

Purpose To evaluate the gene expression of peroxisome proliferator activated receptors gamma (PPARG) in colorectal tumors and to correlate this data with clinical variables of the patients. Methods We analyzed the gene expression of PPARG in 50 samples of colorectal tumors using real-time reverse transcription polymerase chain reaction, and 20 adjacent normal tissue samples as control. The results of these quantifications were correlated with the respective patients' medical records' clinical information. Results PPARG expression was not different in the tumor tissue compared to the control tissue. Patients older than 60 years, histological type with mucinous differentiation, more advanced staging at the time of diagnosis, and patients who evolved with recurrence of the disease or death did not present higher PPARG expression. Conclusion Expression of PPARGD was not associated with worse prognosis.

Apoptosis related microRNAs and MGMT in glioblastoma cell lines submitted to treatments with ionizing radiation and temozolomide.

AIM: To evaluate the effect of radiotherapy and temozolomide on the expression of miRNAs apoptotic (miRNAs-21, -221, -222 (anti-apoptotic) and miRNAs-15a, -16 (pro-apoptotic)) and the gene MGMT in glioblastoma cell lines. BACKGROUND: The limited knowledge of the molecular biology of malignant gliomas may hinder the development of therapeutic modalities. In this scenario, one of the greatest advances of recent years was the identification of microRNAs. These molecules have an important role in biological processes involving cancer, including glioblastoma. MATERIALS AND METHODS: Trypan blue was used to verify the cell viability, and real time PCR to quantify the expression of microRNAs and gene 24, 48 and 120 h after exposure to treatments. RESULTS: There was a statistically significant decrease of expression of miR-15a between 48 and 120 h in line T98 G treated with radiation, increased expression of miR-15a between 24 and 120 h in line U251 treated with radiation and temozolomide, and increased expression of miR-16 between 24 and 120 h in line U251 treated with radiation alone and when combined with temozolomide. There was a decrease in MGMT gene expression, between 24 and 48 h in U343 cells treated with temozolomide. CONCLUSIONS: Ionizing radiation and temozolomide modified the expression of miRNAs studied and MGMT.

Morphological and molecular analysis of apoptosis in the corpus cavernosum of rats submitted to a chronic alcoholism model.

PURPOSE: To evaluate the effect of chronic alcoholism on morphometry and apoptosis mechanism and correlate with miRNA-21 expression in the corpus cavernosum of rats. METHODS: Twenty-four rats were divided into two experimental groups: Control (C) and Alcoholic group (A). After two weeks of an adaptive phase, rats from group A received only ethanol solution (20%) during 7 weeks. The morphometric and caspase-3 immunohistochemistry analysis were performed in the corpus cavernosum. The miRNA-21 expression was analyzed in blood and cavernous tissue. RESULTS: Chronic ethanol consumption decreased cavernosal smooth muscle area of alcoholic rats. The protein expression of caspase 3 in the corpus cavernosum was higher in A compared to the C group. There was no difference in the expression of miRNA-21 in serum and cavernous tissue between the groups. CONCLUSION: Chronic ethanol consumption reduced smooth muscle area and increased caspase 3 in the corpus cavernosum of rats, without altered serum and cavernosal miR-21 gene expression.

AIF, PARP-1 and MicroRNA-9 expression in cerebral ischemia associated to alcoholism experimental model / Expresión de AIF, PARP-1 y MicroRNA-9 de isquemia cerebral asociado a un modelo experimental de alcoholismo

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.

El consumo crónico de alcohol provoca un empeoramiento de los eventos que siguen a la isquemia cerebral. Estos eventos están regulados a través de la expresión de varios genes y microRNA. El objetivo de este trabajo fue analizar y describir el perfil de expresión de las proteínas PARP y AIF y microRNA-9 en ratas sometidas a isquemia cerebral focal, asociadas o no, con el modelo de alcoholismo crónico. Veinte ratas Wistar adultas se dividieron en: grupo control, isquémico alcohólico, e isquémico / alcoholizado para análisis inmunohistoquímico y expresión de genes microRNA-9. Resultados: Hubo una reducción en la expresión de proteínas de PARP-1 y un marcado positivo para AIF en el grupo isquémico / alcoholizado. No se observó una expresión significativa en el microRNA-9. La asociación de la isquemia con el consumo crónico de alcohol promovió una tendencia a la baja expresión de microRNA-9, baja expresión de PARP1 y alta expresión de AIF, lo que indica una interferencia en el efecto protector de microRNA-9 en los otros grupos.

Modulation of NMDA receptor by miR-219 in the amygdala and hippocampus of patients with mesial temporal lobe epilepsy.

Mesial temporal lobe epilepsy with hippocampal sclerosis is the most frequent form of focal epilepsy in adults, and it is often refractory to drug treatment. Regardless of the efforts on developing new antiepileptic drugs for refractory cases, studies suggest a need for better understanding the molecular bases of epilepsy. The microRNAs have been progressively investigated as potential targets for both epilepsy mechanisms elucidation and treatment. Therefore, the goal of this study was to evaluate the differential expression of miR-219, miR-181b, and miR-195, previously described as regulators of the excitatory neurotransmitter receptors NMDA-R1 and AMPA-GluR2 and inhibitory neurotransmitter GABAA (α2, ß3, and γ2 subunits) in the amygdala and hippocampus of patients with mesial temporal lobe epilepsy. Based on genes and miRNAs' quantitative Polymerase Chain Reaction (qPCR) from 18 patients with epilepsy, our results showed an inverse relationship between miR-219 and NMDA-NR1 expression in both the amygdala and hippocampus in comparison to their expression in controls. NR1 and GluR2 were upregulated in the amygdala of epileptic patients. Low miR-195 expression was observed in the amygdala of patients with epilepsy. Our findings indicate that miR-219 has a possible regulatory role in excitatory neurotransmission in patients with epilepsy, contributing to the new avenue of miRNA biology in drug-resistant epilepsy, reserving huge potential for future applications and clinical interventions in conjunction with existing therapies.

Analysis of Caspase-9 protein and microRNAs miR-21, miR-126 and miR-155 related to the apoptosis mechanism in the cerebellum of rats submitted to focal cerebral ischemia associated with an alcoholism model.

OBJECTIVE: This study aimed to analyze the cerebellum of rats submitted to an experimental focal cerebral ischemia, by middle cerebral artery occlusion for 90 minutes, followed by reperfusion for 48 hours, associated with an alcoholism model. METHODS: Fifty adult Wistar rats were used, subdivided into five experimental groups: control group (C): animals submitted to anesthesia only; sham group (S): animals submitted to complete simulation of the surgical procedure; ischemic group (I): animals submitted to focal cerebral ischemia for 90 minutes followed by reperfusion for 48 hours; alcoholic group (A): animals that received daily absolute ethanol diluted 20% in water for four weeks; and, ischemic and alcoholic group (I + A): animals receiving the same treatment as group A and, after four weeks, submitted to focal cerebral ischemia for 90 minutes, followed by reperfusion for 48 hours. The cerebellum samples were collected and immunohistochemical analysis of Caspase-9 protein and serum analysis by RT-PCR of microRNAs miR-21, miR-126 and miR155 were performed. RESULTS: The expression of Caspase-9 was higher in groups I, A and I + A. In the microRNAs analyses, miR-126 was higher in groups A and I + A, miR-155 was higher in groups I and I + A. CONCLUSIONS: We conclude that apoptosis occurs in the cerebellar cortex, even if it is distant from the ischemic focus, and that microRNAs 126 and 155 show a correlation with cellular apoptosis in ischemic rats and those submitted to the chronic alcohol model.

Analysis of Caspase-9 protein and microRNAs miR-21, miR-126 and miR-155 related to the apoptosis mechanism in the cerebellum of rats submitted to focal cerebral ischemia associated with an alcoholism model / Análise da proteína Caspase-9 e dos microRNAs miR-21, miR-126 e miR-155 relacionados ao mecanismo de apoptose no cerebelo de ratos submetidos à isquemia cerebral focal associada ao modelo de alcoolismo

ABSTRACT This study aimed to analyze the cerebellum of rats submitted to an experimental focal cerebral ischemia, by middle cerebral artery occlusion for 90 minutes, followed by reperfusion for 48 hours, associated with an alcoholism model. Methods Fifty adult Wistar rats were used, subdivided into five experimental groups: control group (C): animals submitted to anesthesia only; sham group (S): animals submitted to complete simulation of the surgical procedure; ischemic group (I): animals submitted to focal cerebral ischemia for 90 minutes followed by reperfusion for 48 hours; alcoholic group (A): animals that received daily absolute ethanol diluted 20% in water for four weeks; and, ischemic and alcoholic group (I + A): animals receiving the same treatment as group A and, after four weeks, submitted to focal cerebral ischemia for 90 minutes, followed by reperfusion for 48 hours. The cerebellum samples were collected and immunohistochemical analysis of Caspase-9 protein and serum analysis by RT-PCR of microRNAs miR-21, miR-126 and miR155 were performed. Results The expression of Caspase-9 was higher in groups I, A and I + A. In the microRNAs analyses, miR-126 was higher in groups A and I + A, miR-155 was higher in groups I and I + A. Conclusions We conclude that apoptosis occurs in the cerebellar cortex, even if it is distant from the ischemic focus, and that microRNAs 126 and 155 show a correlation with cellular apoptosis in ischemic rats and those submitted to the chronic alcohol model.

RESUMO O objetivo deste estudo foi analisar o cerebelo de ratos submetidos à isquemia cerebral focal experimental, por oclusão da artéria cerebral média por 90 minutos, seguida de reperfusão por 48 horas, associada a um modelo de alcoolismo. Métodos Foram utilizados 50 ratos Wistar adultos, subdivididos em cinco grupos experimentais: grupo controle (C): animais submetidos apenas à anestesia; grupo sham (S): animais submetidos à simulação completa do procedimento cirúrgico; grupo isquêmico (I): animais submetidos à isquemia cerebral focal por 90 minutos, seguidos de reperfusão por 48 horas; grupo alcoólico (A): animais que receberam etanol absoluto diário diluído em 20% em água por quatro semanas; e grupo isquêmico e alcoólico (I + A): animais que recebem o mesmo tratamento do grupo A e, após quatro semanas, submetidos à isquemia cerebral focal por 90 minutos, seguidos de reperfusão por 48 horas. As amostras de cerebelo foram coletadas e a análise imuno-histoquímica da proteína Caspase-9 e a análise sérica por RT-PCR dos microRNAs miR-21, miR-126 e miR155 foram realizadas. Resultados A expressão de Caspase-9 foi maior nos grupos I, A e I + A. Nas análises de microRNAs, o miR-126 foi maior nos grupos A e I + A, o miR-155 foi maior nos grupos I e I + A. Conclusões Concluímos que a apoptose ocorre no córtex cerebelar, mesmo distante do foco isquêmico, e que os microRNAs 126 e 155 mostram uma correlação com a apoptose celular em ratos isquêmicos e submetidos ao modelo crônico de álcool.

Expression of MicroRNAs miR-145, miR-181c, miR-199a and miR-1183 in the Blood and Hippocampus of Patients with Mesial Temporal Lobe Epilepsy.

The aim of this study was to analyze the expression profiles of the microRNAs (miRNAs) miR-145, miR-181c, miR-199a and miR-1183 in the hippocampus and blood of patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and to investigate whether these can be used as diagnosis and prognosis biomarkers for epilepsy. Hippocampus and blood samples were collected from 20 patients with MTLE-HS, ten of whom had a favorable surgical outcome (Engel I) and ten with an unfavorable surgical outcome (Engel III-IV). Hippocampus samples from autopsied individuals with no neurological or psychiatric medical history (necropsy samples) and blood samples from healthy individuals were used as controls. Real-time quantitative PCR (RQ-PCR) was used to analyze miRNA expression. The results showed that the expressions of these miRNAs differed quantitatively in the hippocampus and blood of patients with MTLE-HS in comparison to the respective control. This difference was most pronounced for miR-145, which was hypo-expressed in the hippocampus and hyper-expressed in the blood of MTLE-HS patients. MiRNAs miR-145, miR-181c, miR-199a and miR-1183 were hyper-expressed in the blood of patients with MTLE-HS. No statistical differences in the levels of these miRNAs in the blood or hippocampus were found between Engel I patients and Engel III-IV patients. These results suggest that the analyzed microRNAs are potential circulating biomarkers for epilepsy diagnosis.

microRNA-181d associated with the methylation status of the MGMT gene in Glioblastoma multiforme cancer stem cells submitted to treatments with ionizing radiation and temozolomide.

Despite the increased understanding of the oncological mechanisms underlying Glioblastoma multiforme (GBM) pathophysiology, and recent advances in therapeutic strategies such as maximal surgical resection and post-operative radiotherapy with concomitant and adjuvant temozolomide chemotherapy, the prognosis for patients with brain tumors remains limited. Evidences indicate that the assessment of DNA methylation status in cancer stem cells would allow identifying molecules expressed in these cells, to lead to targeted elimination of this critical population from brain tumors, making the glioblastoma treatment more effective. This study aimed to analyze the role of microRNA-181d associated with the methylation status of the O6-methylguanine methyl transferase (MGMT) gene in Glioblastoma multiforme cancer stem cells subjected to treatment with temozolomide and ionizing radiation. Such responses were analyzed in terms of cell survival, evaluation of the MGMT gene methylation status by MS-HRM (Methylation-Sensitive High Resolution Melting), and analysis of miRNA-181d and MGMT gene expression by relative quantification of mRNA levels in cancer stem cells subjected to treatment with temozolomide and ionizing radiation, isolated or combined. We showed that ionizing radiation and temozolomide reduced the viability of cancer stem cells from GBM patients, as well as modified MGMT gene and miRNA-181d expression in cancer stem cells, suggesting that miRNA-181d interferes in the glioblastoma cancer stem cell response to treatment with temozolomide and ionizing radiation.

Spontaneous subdural hematoma associated with microcystic meningioma: first case report in the literature.

Background: Non traumatic subdural hematomas are rare, especially those associated with intracranial meningiomas. Among the most common meningiomas associated with spontaneous bleeding are angioblastic and malignant meningioma variants. The pathophysiological mechanisms of this association are not yet fully understood. The association of chronic subdural hematoma with microcystic meningioma histological subtype has not yet been described in the literature. Case report: The authors present a case report of a patient with a spontaneous non traumatic chronic subdural hematoma associated with a microcystic subtype grade I meningioma of the parietal convexity. Epidemiological, etiology, natural history, pathophysiology, risk factors of bleeding and treatment options are reviewed. Conclusion: Spontaneous subdural hematomas associated with meningiomas are rare, specially related to the microcystic variant of meningioma. Careful pre-operative consideration of specific anatomy and pathophysiological features are paramount to their full treatment.

Morphological and immunohistochemical analysis of proteins CASPASE 3 and XIAP in rats subjected to cerebral ischemia and chronic alcoholism.

PURPOSE: To evaluate histopathological and ultrastructural changes and expression of proteins related to apoptosis CASPASE 3 and XIAP after experimental induction of temporary focal cerebral ischemia (90 minutes) due to obstruction of the middle cerebral artery in alcoholism model. METHODS: Forty adult Wistar rats were used, subdivided into 5 experimental groups: control group (C); Sham group (S); Ischemic group (I); Alcoholic group (A); and Ischemic and Alcoholized group (I+A): animals submitted to the same treatment of group A and after four weeks were submitted to focal cerebral ischemia during 90 minutes, followed by reperfusion of 48 hours. Were processed for histopathological analysis and immunohistochemistry (for the protein expression of CASPASE -3 and XIAP). RESULTS: Greater histopathological changes were observed in the animals of groups I and I+A in the three areas analyzed. The neuronal loss was higher in the medial striatum region of the animals of groups I and I + A. The protein expression of CASPASE -3 was higher than that of XIAP in the groups I and I + A for both proteins. CONCLUSION: The expression of XIAP was slightly higher where the histopathological changes and expression of CASPASE -3 was less evident.