In vivo models to study neurogenesis and associated neurodevelopmental disorders—Microcephaly and autism spectrum disorder

Abstract

The genesis and functioning of the central nervous system are one of the most intricate and intriguing aspects of embryogenesis. The big lacuna in the field of human CNS development is the lack of accessibility of the human brain for direct observation during embryonic and fetal development. Thus, it is imperative to establish alternative animal models to gain deep mechanistic insights into neurodevelopment, establishment of neural circuitry, and its function. Neurodevelopmental events such as neural specification, differentiation, and generation of neuronal and non-neuronal cell types have been comprehensively studied using a variety of animal models and in vitro model systems derived from human cells. The experimentations on animal models have revealed novel, mechanistic insights into neurogenesis, formation of neural networks, and function. The models, thus serve as indispensable tools to understand the molecular basis of neurodevelopmental disorders (NDDs) arising from aberrations during embryonic development. Here, we review the spectrum of in vivo models such as fruitfly, zebrafish, frog, mice, and nonhuman primates to study neurogenesis and NDDs like microcephaly and Autism Spectrum Disorder. We also discuss nonconventional models such as ascidians and the recent technological advances in the field to study neurogenesis, disease mechanisms, and pathophysiology of human NDDs.

Aberrant Hippocampal Neuroregenerative Plasticity in Schizophrenia: Reactive Neuroblostosis as a Possible Pathocellular Mechanism of Hallucination

“…During embryogenesis, the generation of neurons from embryonic NSCs-derived neuroblasts plays a key role in neurodevelopmental, whereas pathogenic processes in neurodevelopmental disorders and mental disturbances have been attributed to defects in the early neurogenic process [128,129]. Among various predictions, a potential link between schizophrenia and aberrant neurogenic events responsible for unrecognizable abnormal brain development in early life has been widely considered to have a negative impact in the latter adulthood stage leading to psychiatric disturbance and neurocognitive impairments [31,130,131].…”