# The Effects of Microgravity on Differentiation and Regeneration in Neural Stem Cells

## TL;DR

This paper reviews how microgravity affects neural stem cells, showing both promoting and inhibiting effects on their growth and regeneration.

## Contribution

It synthesizes conflicting findings on microgravity's impact on NSCs and explores underlying mechanisms for space and regenerative medicine.

## Key findings

- Real spaceflight increases NSC proliferation but reduces neurosphere volume.
- RWV systems promote neuron and astrocyte generation, while RCCSs inhibit differentiation.
- Phenotypic outcomes depend on experimental conditions, cell sources, and observation time.

## Abstract

What are the main findings?
In scientific research, perspectives diverge on microgravity’s impact on neural stem cell (NSC) development, with some studies indicating promotion and others inhibition.This review clarifies the key features of NSCs, examines the contrasting effects of microgravity on their development and regeneration (both promoting and inhibiting), and explores the underlying molecular and cellular mechanisms. These insights offer valuable guidance for NSC-based therapies in space and regenerative medicine.

In scientific research, perspectives diverge on microgravity’s impact on neural stem cell (NSC) development, with some studies indicating promotion and others inhibition.

This review clarifies the key features of NSCs, examines the contrasting effects of microgravity on their development and regeneration (both promoting and inhibiting), and explores the underlying molecular and cellular mechanisms. These insights offer valuable guidance for NSC-based therapies in space and regenerative medicine.

What are the implications of the main findings?
These findings are expected to inspire novel approaches for studying neural systems pertinent to space medicine while facilitating the optimization of NSC applications in regenerative medicine.

These findings are expected to inspire novel approaches for studying neural systems pertinent to space medicine while facilitating the optimization of NSC applications in regenerative medicine.

Neural stem cells (NSCs) are self-renewing, multipotent cells of the central nervous system (CNS) that can differentiate into a range of specialized cell types, including neurons, astrocytes, and oligodendrocytes (OLs). Due to their remarkable ability to self-renew and differentiate, NSCs hold immense potential for the treatment of neurodegenerative diseases (NDDs). However, clinical translation remains hindered by challenges such as expansion difficulties and phenotypic drift. This review synthesizes evidence on the divergent effects of microgravity on NSC biology. While real spaceflight has been shown to enhance NSC proliferation, it paradoxically reduces neurosphere volume. Microgravity simulations yield contrasting results: rotating wall vessel (RWV) systems promote neuron and astrocyte generation, whereas rotating cell culture systems (RCCSs) inhibit differentiation despite the use of pro-differentiation media. These phenotypic variations critically depend on experimental conditions, cell sources, and observation time. Future research should focus on elucidating cross-pathway interactions and optimizing culture parameters to enable clinical-scale NSC applications.