The Brain-Like Enteric Nervous System

Understanding the autonomic supply at the gastrointestinal tract is one of the significant challenges for science. Its complex network of neurons exists on a broad evolutionary scale, from Hydra to mammals, and in a higher number than those found in the vertebrate spinal cord. Inside the gastrointestinal tract, enteric neurons regulate several functions with intrinsic processes and communicate with the other complex known as the microbiome. Outside the gastrointestinal tract, the enteric neurons project to the brain stem and spinal cord via the gut–brain axis. Furthermore, this enteric system has close functional relationships with the immune system for a rapid response to unhealthy food. The present chapter focuses on the structure, function, and pathologies of the enteric nervous system

Multiunit Recording of Cerebellar Cortex in Autistic Male Rats during Social Interaction in Enriched Environments

Autism in humans is a lifelong behavioral disorder that typically manifests in early infancy, primarily affecting boys. It arises from neurodevelopmental changes that significantly impact social behavior, with the cerebellum being one of the principal affected regions. In this study, we investigated the cerebellum in an autism animal model, recording the multiunit activity of cerebellar vermis lobules 6 and 7 (L6 and L7) in male rats with autism-like behavior induced by postnatal valproate treatment. Two groups were formed: control (Ctrl) and experimental (VPA) males, which were further divided based on their living conditions into standard (Std) or enriched environments (EE). Social arenas were used for recording purposes. Both groups and lobules showed increased multiunit amplitude during social interaction (SI) and vertical exploration (VE), with higher amplitudes observed in VPA males. Interestingly, the EE significantly reduced the amplitude during SI, suggesting that EE promotes neural plasticity, resulting in improved social responses with fewer activated neurons, meaning improved activity with less energy consumption. Consequently, EE proves to be a valuable strategy for addressing the challenges associated with autism behavior

Nigral degeneration correlates with persistent activation of cerebellar Purkinje cells in MPTP-treated monkeys

In the present work we analyze the cerebellum of chronic parkinsonian monkeys in order to clarify whether chronic mesencephalic depletion is associated with long term activation of the cerebellar neurons in chronic Parkinsonism. In our study, we observed a persistent activation of Purkinje cells in the cerebellum of chronic parkinsonian macaques, characterized by the expression of c-Fos, which correlated with dopaminergic degeneration. These results are compatible with the results observed in fMRI in Parkinson’s disease patients, and may contribute to the understanding of additional alterations in the brain circuitry in Parkinsonis

Effect of Enriched Environment on Cerebellum and Social Behavior of Valproic Zebrafish

The etiology of autism spectrum disorder (ASD) has been linked to both genetic and epigenetic factors. Among the epigenetic factors, exposure to valproic acid (VPA), an antiepileptic and mood-modulating drug, has been shown to induce characteristic traits of ASD when exposed to during embryogenesis. Conversely, in animal models, enriched environment (EE) has demonstrated positive behavioral and neural effects, suggesting its potential as a complementary treatment to pharmacological approaches in central nervous system disorders. In this study, we utilized zebrafish to model ASD characteristics induced by VPA and hypothesized that sensory stimulation through EE could ameliorate the behavioral and neuroanatomical features associated with ASD. To test this hypothesis, we assessed social behavior, cerebellar volume, and Purkinje cell populations via histology and immunohistochemistry after exposing the fish to EE. The results revealed that zebrafish exposed to VPA exhibited social deficits, reduced cerebellar cortex volume, and a decrease in c-Fos-positive cells in the Purkinje layer. In contrast, VPA-exposed fish treated with EE showed increased socialization, augmented cerebellar cortex volume, and an elevation in c-Fos-positive Purkinje cells. These findings suggest that alterations induced by VPA may be ameliorated through EE treatment, highlighting the potential therapeutic impact of sensory stimulation in conditions related to ASD