Deciphering Age‐Dependent <scp>ECM</scp> Remodelling in Liver: Proteomic Profiling and Its Implications for Aging and Therapeutic Targets

Aging is characterised by progressive structural and functional changes in the liver, with the extracellular matrix (ECM) playing a key role in modulating these changes. Our study presents a comprehensive proteomic analysis of the liver ECM across different age stages, uncovering significant age-related changes. Through the identification of 158 ECM proteins in decellularised rat liver scaffolds, we reveal the intricate relationship between ECM composition and liver maturation, as well as the decrease in regenerative capacity. Lumican was identified as a critical regulator with heightened expression in neonatal livers, which is associated with enhanced hepatocyte proliferation and maintenance of stem cell characteristics. Temporal expression analysis distinguished four distinct clusters of ECM proteins, each reflecting the liver's functional evolution from early development to old age. Early developmental stages were marked by proteins essential for liver growth, while adulthood was characterised by a robust ECM supporting metabolic functions. Middle age showed a regulatory shift towards protease balance, and later life was associated with haemostasis-related processes. Our findings underscore the multifaceted role of the ECM in liver health and aging, offering potential opportunities for therapeutic intervention to counteract age-induced liver dysfunction. This study provides a foundational understanding of ECM dynamics in liver aging and sets the stage for the development of innovative strategies to mitigate the effects of age-related liver decline.