Unlocking Neural Function with 3D In Vitro Models: A Technical Review of Self-Assembled, Guided, and Bioprinted Brain Organoids and Their Applications in the Study of Neurodevelopmental and Neurodegenerative Disorders

Abstract

Understanding the complexities of the human brain and its associated disorders poses a significant challenge in neuroscience. Traditional research methods have limitations in replicating its intricacies, necessitating the development of in vitro models that can simulate its structure and function. Three-dimensional in vitro models, including organoids, cerebral organoids, bioprinted brain models, and functionalized brain organoids, offer promising platforms for studying human brain development, physiology, and disease. These models accurately replicate key aspects of human brain anatomy, gene expression, and cellular behavior, enabling drug discovery and toxicology studies while providing insights into human-specific phenomena not easily studied in animal models. The use of human-induced pluripotent stem cells has revolutionized the generation of 3D brain structures, with various techniques developed to generate specific brain regions. These advancements facilitate the study of brain structure development and function, overcoming previous limitations due to the scarcity of human brain samples. This technical review provides an overview of current 3D in vitro models of the human cortex, their development, characterization, and limitations, and explores the state of the art and future directions in the field, with a specific focus on their applications in studying neurodevelopmental and neurodegenerative disorders.

Metabolic dynamics in astrocytes and microglia during post-natal development and their implications for autism spectrum disorders

“…Additionally, investigating the impact of environmental factors, such as nutrition and inflammation, on glial cell function and metabolism during critical developmental periods may offer insights into preventive strategies. In the realm of future perspectives, leveraging evolving model systems, particularly those derived from human-induced pluripotent stem cells (hiPSC), holds tremendous promise in advancing our comprehension of the intricate relationship between astrocytes, microglia ( Bezzi, 2022 ; Cordella et al, 2022 ; D’Antoni et al, 2023 ), and metabolic pathways in the context of ASDs. The development and integration of hiPSC-derived microglia and astrocytes into experimental frameworks offers an unprecedented opportunity to investigate the dynamic interplay of these glial cells in a human-specific context.…”

Human-Organoid-Based In Vitro Modeling for Environmental Toxicology

“…This becomes particularly concerning when PSCs undergo guided differentiation, where differentiation factors, including small molecules, produce off-target effects that ultimately affect cell fate. − Consequently, epigenetic modifications are often overlooked but have the potential to significantly affect downstream cellular responses . To precisely identify epigenetic changes, one of the most widely performed routine monitoring methods is karyotyping the PSCs every certain number of passages . In addition, the use of chromatin immunoprecipitation (ChIP-seq) allows the identification of certain transcription factors occupying various regions of the genome.…”

“…17 To precisely identify epigenetic changes, one of the most widely performed routine monitoring methods is karyotyping the PSCs every certain number of passages. 31 In addition, the use of chromatin immunoprecipitation (ChIPseq) allows the identification of certain transcription factors occupying various regions of the genome. This analysis, in conjunction with other multiomics approaches, enables a more sensitive determination of specific transcriptional regions of interest.…”

Methoxyfuranocoumarins of Natural Origin–Updating Biological Activity Research and Searching for New Directions—A Review

“…Unfortunately, three-dimensional (3D) cell models/organoids for assessing the bioactivity of MFCs are still not available, and it should be emphasized that this may be a new approach worth trying, as the test model seems to be similar to in vivo tests. Threedimensional organoids and organs on a chip are rapidly evolving, and these techniques have been widely characterized [40,41]. For example, three-dimensional (3D) in vitro models of the human brain, such as organoids, bioprinted three-dimensional models of brain tissues or functionalized organoids, may be important in the study of both stages of development and pathological changes within this organ [42], taking into account specific aspects such as anatomy, interactions at the cellular level and gene expression.…”