# Single-cell omics reveals arg-1 as a key regulator of age-dependent macrophage-mediated cartilage repair

## TL;DR

This study shows that Arg-1 helps control inflammation in aged macrophages, improving cartilage repair in older animals.

## Contribution

The study identifies Arg-1 as a novel regulator of macrophage function in age-related cartilage repair.

## Key findings

- Aged animals show reduced anti-inflammatory macrophage subsets in cartilage injury.
- Overexpression of Arg-1 rescues impaired cartilage repair in aged animals.
- Arg-1 is a potential therapeutic target for age-related tissue regeneration.

## Abstract

Aging impairs cartilage repair, with young animals exhibiting superior regenerative capacity due to enhanced tissue repairing and reduced inflammation compared to aged counterparts. This study employed single-cell omics to dissect age-dependent immune cell heterogeneity in cartilage injury, revealing a critical deficiency in anti-inflammation macrophage subsets in aged animals. We identified Arg-1 as a central regulator of macrophage polarization, demonstrating that its overexpression rescues impaired repair in aged animals. These findings establish Arg-1 as a novel therapeutic target to counteract age-related declines in cartilage regeneration, offering new insights into macrophage-driven tissue repair mechanisms. The integration of single-cell analysis with functional validation provides a framework for developing precision interventions for age-impaired tissue regeneration.