Neuroscience, Behavioral Neuroscience, Cellular and Molecular Neuroscience, Developmental Neuroscience
9
Scopus Publications
Scopus Publications
Environmental signals on microglial function during brain development, neuroplasticity, and disease Luana da Silva Chagas, Poliana Capucho Sandre, Natalia Cristina Aparecida Ribeiro e Ribeiro, Henrique Marcondes, Priscilla Oliveira Silva, et al. International Journal of Molecular Sciences, 2020 Recent discoveries on the neurobiology of the immunocompetent cells of the central nervous system (CNS), microglia, have been recognized as a growing field of investigation on the interactions between the brain and the immune system. Several environmental contexts such as stress, lesions, infectious diseases, and nutritional and hormonal disorders can interfere with CNS homeostasis, directly impacting microglial physiology. Despite many encouraging discoveries in this field, there are still some controversies that raise issues to be discussed, especially regarding the relationship between the microglial phenotype assumed in distinct contexts and respective consequences in different neurobiological processes, such as disorders of brain development and neuroplasticity. Also, there is an increasing interest in discussing microglial–immune system cross-talk in health and in pathological conditions. In this review, we discuss recent literature concerning microglial function during development and homeostasis. In addition, we explore the contribution of microglia to synaptic disorders mediated by different neuroinflammatory outcomes during pre- and postnatal development, with long-term consequences impacting on the risk and vulnerability to the emergence of neurodevelopmental, neurodegenerative, and neuropsychiatric disorders.
Intravitreous injection of interleukin-6 leads to a sprouting in the retinotectal pathway at different stages of development Grasielle D. Menezes, Vanessa G. Goulart, Sheila Espírito-Santo, Priscilla Oliveira-Silva, Claudio Alberto Serfaty, et al. Neuroimmunomodulation, 2016 Objective: The development of retinotectal pathways form precise topographical maps is usually completed by the third postnatal week. Cytokines participate in the development and plasticity of the nervous system. We have previously shown that in vivo treatment with interleukin 2 disrupts the retinocollicular topographical order in early stages of development. Therefore, we decided to study the effect of a single intravitreous injection of IL-6 upon retinotectal circuitry in neonates and juvenile rats. Materials and Methods: Lister Hooded rats received an intravitreous injection of IL-6 (50 ng/ml) or vehicle (PBS) at either postnatal day (PND)10 or PND30 and the ipsilateral retinotectal pathway was evaluated 4 or 8 days later, respectively. Results: Our data showed that, at different stages of development, a single IL-6 intravitreous treatment did not produce an inflammatory response and increased retinal axon innervation throughout the visual layers of the superior colliculus. Conclusions: Taken together, our data provide the first evidence that a single intravitreous injection with IL-6 leads to sprouting in the subcortical visual connections and suggest that small changes in IL-6 levels might be sufficient to impair the correct neuronal circuitry fine-tuning during brain development.
Nutritional tryptophan restriction and the role of serotonin in development and plasticity of central visual connections Claudio A. Serfaty, Priscilla Oliveira-Silva, Adriana da Cunha Faria Melibeu, Paula Campello-Costa Neuroimmunomodulation, 2008 Tryptophan is an essential amino acid and metabolic precursor of serotonin. Serotonin is both a classical neurotransmitter and a signaling molecule that plays crucial roles in the development of neural circuits and plasticity. The specification of neural circuits in rodents occurs during the postnatal period with conspicuous influence of environmental factors including the nutritional status. Sensory, motor and cognitive systems develop during a critical period, a time window that is crucial to the use-dependent organization of neuronal circuits. This review presents recent experimental findings that disclose some mechanism of tryptophan- and serotonin-dependent plasticity in the developing and adult brain.
Matrix metalloproteinase-9 is involved in the development and plasticity of retinotectal projections in rats Priscilla Oliveira-Silva, Patricia B. Jurgilas, Pablo Trindade, Paula Campello-Costa, Jonas Perales, et al. Neuroimmunomodulation, 2007 <i>Objective:</i> During postnatal development, retinotectal projections undergo a process of misplaced axon elimination, leading to a topographical matching between the retinal surface and the superior colliculus. Matrix metalloproteinases (MMPs) have been implicated in the development and plasticity of the nervous system. We studied the expression and role of MMPs during normal development of retinotectal projections and after monocular enucleation-induced plasticity. <i>Material and Methods:</i> Lister hooded rats at different postnatal ages received subpial ethylene vinyl acetate 40W implants to deliver an MMP inhibitor or vehicle to the superior colliculus. Animals received intraocular injections of horseradish peroxidase for anterograde tracing of ipsilateral projections. For immunoblotting and zymography, colliculi were removed without fixation. <i>Results:</i> We observed the highest MMP activity in the first postnatal week, with decreasing activity thereafter. Monocular enucleation at postnatal day 10 yielded a rapid increase in MMP activity, 24 h following denervation of the contralateral colliculus. Importantly, inhibition of MMP activity in vivo induced a marked delay of axonal clustering along the medial aspect of colliculus. <i>Conclusions:</i> Our data indicate that MMPs are crucial in retinotectal development concurring to the fine tuning of topographical order and synaptic specificity of these connections.
