The effects of altered neurogenic microRNA levels and their involvement in the aggressiveness of periventricular glioblastoma.

INTRODUCTION: Glioblastoma multiforme is the most common primary brain tumour, with the least favourable prognosis. Despite numerous studies and medical advances, it continues to be lethal, with an average life expectancy of 15 months after chemo-radiotherapy. DEVELOPMENT: Recent research has addressed several factors associated with the diagnosis and prognosis of glioblastoma; one significant factor is tumour localisation, particularly the subventricular zone, which represents one of the most active neurogenic niches of the adult human brain. Glioblastomas in this area are generally more aggressive, resulting in unfavourable prognosis and a shorter life expectancy. Currently, the research into microRNAs (miRNA) has intensified, revealing different expression patterns under physiological and pathophysiological conditions. It has been reported that the expression levels of certain miRNAs, mainly those related to neurogenic processes, are dysregulated in oncogenic events, thus favouring gliomagenesis and greater tumour aggressiveness. This review discusses some of the most important miRNAs involved in subventricular neurogenic processes and their association with glioblastoma aggressiveness. CONCLUSIONS: MiRNA regulation and function play an important role in the development and progression of glioblastoma; understanding the alterations of certain miRNAs involved in both differentiation and neural and glial maturation could help us to better understand the malignant characteristics of glioblastoma.

Behavioral changes in models of chemoconvulsant-induced epilepsy: A review.

Epilepsy is one of the most common neurological disorders in the general population and affects over 50 million people worldwide. Epilepsy is characterized by the presence of spontaneous recurrent seizures as a result of sudden and abnormal electrical activity in specific areas of the cerebral cortex. However, this condition encompasses much more than simply the presence of seizures. Cognitive problems and behavioral impairments are also frequent actors, as well as mood disorders. These must be precisely described in order to develop more successful pharmacological, or even behavioral, treatments. We review some of the fundamental behavioral experimental rodent protocols that have recently been applied to the study of behavioral impairments in epilepsy, particularly in epilepsy modeled by different chemoconvulsants, such as pilocarpine or kainic acid. These experimental protocols are classified into two categories: Tests designed for studying emotional factors, and those designed for studying cognitive impairments and social behavior. Behavioral impairments and adaptations identified by the use of these procedures are described.