Propentofylline decreases hypothalamic astrogliosis induced by hypercaloric diet in the rat / A propentofilina diminui a astrogliose hipotalâmica induzida pela dieta hipercalórica no rato

ABSTRACT Obesity is associated with a chronic and low-grade inflammatory response in the hypothalamus, where astrogliosis occurs with the upregulation of the astrocyte structural protein GFAP. As propentofylline (PPF) has inhibitory effects on astrocyte and microglial activation during inflammation, this study aimed to investigate if this xanthine derivative could decrease the astrocyte reaction induced by a hypercaloric diet (HD). Male Wistar rats were divided into four groups: NDS - rats receiving a normocaloric diet (ND) and daily saline solution; NDP - rats receiving ND and daily PPF (12.5 mg/kg/day, intraperitoneal route); HDS - rats receiving HD and saline solution, HDP - rats receiving HD and PPF. On the 21st day, rats were anesthetized, and perfused, and brains were collected for GFAP immunohistochemical study in the hypothalamus. Results showed that HD induced increased weight gain and hypothalamic astrogliosis. Propentofylline decreased the expression of GFAP in the HDP group, although it did not affect the weight gain induced by this diet.

RESUMO A obesidade está associada com uma resposta inflamatória crônica e de baixo grau no hipotálamo, onde ocorre astrogliose com a superexpressão da proteína astrocitária GFAP. Como a propentofilina (PPF) possui efeitos inibitórios sobre a ativação astrocitária e microglial durante a inflamação, este estudo visou a investigar se esta xantina podia diminuir a reação astrocitária induzida pela dieta hipercalórica (HD). Ratos Wistar machos foram divididos em 4 grupos: NDS- ratos recebendo dieta normocalórica (ND) e solução salina diária; NDP- ratos recebendo ND e PPF diária (12.5 mg/kg/dia, via intraperitoneal); HDS- ratos recebendo HD e solução salina, HDP- ratos recebendo HD e PPF. No 21° dia, os ratos foram perfundidos e os encéfalos, coletados para estudo imuno-histoquímico para a GFAP no hipotálamo. Os resultados mostram que a HD induziu aumento do ganho de peso e astrogliose no hipotálamo. A PPF diminuiu a expressão de GFAP no grupo HD, embora não tenha afetado o ganho de peso induzido por esta dieta.

Glial scar-modulation as therapeutic tool in spinal cord injury in animal models

Abstract Purpose: Spinal Cord injury represents, in veterinary medicine, most of the neurological attendances and may result in permanent disability, death or euthanasia. Due to inflammation resulting from trauma, it originates the glial scar, which is a cell interaction complex system. Its function is to preserve the healthy circuits, however, it creates a physical and molecular barrier that prevents cell migration and restricts the neuroregeneration ability. Methods: This review aims to present innovations in the scene of treatment of spinal cord injury, approaching cell therapy, administration of enzyme, anti-inflammatory, and other active principles capable of modulating the inflammatory response, resulting in glial scar reduction and subsequent functional improvement of animals. Results: Some innovative therapies as cell therapy, administration of enzymes, immunosuppressant or other drugs cause the modulation of inflammatory response proved to be a promising tool for the reduction of gliosis. Conclusion: Those tools promise to reduce gliosis and promote locomotor recovery in animals with spinal cord injury.

effect of bioGlue on cerebral cortex in experimental rats

BioGlue is a newly introduced sealant applied by several cardiovascular surgeons to seal graft anastomoses. This study was carried out to determine the effect of a synthetic BioGlue on the repair of meninges in comparison with contemporary bioadhesives. A synthetic BioGlue was provided by combining 45% human serum albumin and 10% glutaraldehyde. Forty Wistar female rats were randomly divided into 4 equal groups [Two case and two control groups]. After craniotomy, dural incision was performed and the motor cortex was exposed. In the case group, the motor cortex was exposed to BioGlue and in the control group, the incision was closed without application of BioGlue. The rats were studied histpathologically after 5 and 14 days postcraniotomy. Synthetic BioGlue caused an acute inflammatory response that resulted in a delayed gliosis in the superficial cerebral cortex, but the deep layers and adjacent areas of cortex were spared. Inflammatory changes and gliosis did not cause cell apoptosis or necrosis. Histopathological changes did not have any clinical significance as they were not accompanied by any neurological deficit or motor weaknesses and exposure to synthetic BioGlue could not cause any clinically significant neurological deficit either. The simplicity of producing this new synthetic BioGlue and its relative low cost, compared to other similar glues, opens a new horizon to the use of this synthetic BioGlue in the neurosurgical field

Local exposure of 849 MHz and 1763 MHz radiofrequency radiation to mouse heads does not induce cell death or cell proliferation in brain

Even though there is no direct evidence to prove the cellular and molecular changes induced by radiofrequency (RF) radiation itself, we cannot completely exclude the possibility of any biological effect of mobile phone frequency radiation. We established a carousel-type exposure chamber for 849 MHz or 1763 MHz of mobile phone RF radiation to expose RF to the heads of C57BL mice. In this chamber, animals were irradiated intermittently at 7.8 W/kg for a maximum of 12 months. During this period, the body weights of 3 groups-sham, 849 MHz RF, and 1763 MHz RF-did not show any differences between groups. The brain tissues were obtained from 3 groups at 6 months and 12 months to examine the differences in histology and cell proliferation between control and RF exposure groups, but we could not find any change upon RF radiation. Likewise, we could not find changes in the expression and distribution of NeuN and GFAP in hippocampus and cerebellum, or in cell death by TUNEL assay in RF exposure groups. From these data, we conclude that the chronic exposure to 849 MHz and 1763 MHz RF radiation at a 7.8 W/kg specific absorption rate (SAR) could not induce cellular alterations such as proliferation, death, and reactive gliosis.

Gliosis masiva de la retina / Massive retinal gliosis

En un período de cuatro años se revisan 80 casos de leucocoria, encontrándose dos casos anatomopatológicos de gliosis masiva de retina. Se efectúa estudios de microscopía electrónica y estudio inmunohistoquímico. Los hallazgos demostraron que la masa pseudotumoral se debía a proliferación de células fusiformes de citoplasma eosinofílico fibrilar y que el método de la peroxidasa antiperoxidasa confirmó como tejido glial. La microscopía electrónica demostró un patrón similar al presentado por las células de Muller