# Sex-dependent plasticity of adult neural tissue in response to damage

## TL;DR

This study uses fruit flies to show that adult neural tissue in the gut can grow in response to damage, but this ability is specific to females and influenced by sex-related factors.

## Contribution

The paper introduces a simplified model using the fly gut to study sex-dependent neural plasticity and its role in recovery from damage.

## Key findings

- Females show reversible neural tissue growth in response to gut damage, while males do not.
- Antioxidants can suppress damage-induced neural growth, suggesting a role for reactive oxygen species.
- Masculinizing female neurons reduces plasticity, but feminizing male neurons does not induce it.

## Abstract

The plasticity of intact adult neural tissue in the vicinity of neural damage helps restore circuit function. Much remains to be learned about the mechanisms regulating this process and the reported sex differences in recovery outcomes. Here, we present the fly gut and its innervation as a simplified model to address these questions. We show that ingestion of damaging agents triggers a reversible increase in adult enteric neural tissue in females, consistent with growth rather than neurogenesis. This growth can be influenced by gut-derived reactive oxygen species, as suggested by suppression with an antioxidant. Interestingly, males do not display neural plasticity, and masculinization of neurons in females suppresses damage-dependent neural growth. Conversely, feminizing male neurons does not confer plasticity, suggesting that sex-specific cues from surrounding tissues may be required for this response. Blocking plasticity reduces the dextran sulfate sodium-induced increase in defecation and further shortens survival, indicating that female-specific neural plasticity supports both gut function and viability. Together, these findings establish a physiological model to dissect cellular, molecular and sex-dependent regulators of adult neural plasticity relevant to circuit repair.

Summary: The Drosophila gut can be used as a simple system to explore how adult neural tissues differ between sexes in their capacity for plasticity.