Integrative Omics Reveal Female-Specific Benefits of p16

Aging is marked by the accumulation of cells expressing the cyclin-dependent kinase inhibitor p16Ink4a. These p16⁺ cells, largely senescent, contribute to inflammation and tissue dysfunction. While eliminating p16⁺ cells improves healthspan, sex-specific differences in their burden and clearance remain unclear. Through combined transcriptomic, proteomic, and functional analyses, we reveal distinct sex-dependent dynamics of p16⁺ cells during aging. Female mice accumulate significantly more p16⁺ cells across multiple tissues, particularly in the liver. In the p16-3MR model, selective ablation of these cells enhances grip strength, promotes skin regeneration, and reduces liver damage exclusively in females. Multi-omics profiling shows that p16⁺ cell removal shifts female liver expression toward youthful, health-associated profiles, marked by improved mitochondrial activity and reduced inflammatory signaling-molecular patterns resembling those induced by longevity interventions such as calorie restriction, rapamycin, and acarbose. Integrative analysis of our and independent datasets identifies a conserved transcriptional network involving Srm, Cd36, and Lrrfip1, suggesting shared mitochondrial-immune regulatory mechanisms. Overall, our findings establish p16⁺ cells as critical yet heterogeneous drivers of tissue aging, uncover sex-specific differences in their abundance and senolytic responsiveness, and support the development of precision senotherapeutics that consider sex as a key biological variable in aging and rejuvenation.