Senescent cells exhibit higher expression levels of the p16 protein compared to non-senescent cells.

Study: p16 deficiency attenuates intervertebral disc degeneration by adjusting oxidative stress and nucleus pulposus cell cycle

The study shows that when cells are old and worn out (senescent), they have more p16 protein, and when scientists remove p16, the cells act younger and healthier. This means p16 is a sign of old, tired cells.

Study: Decreased number of p16-positive senescent cells in human endometrium as a marker of miscarriage

The study found that women who had successful pregnancies had more p16 protein in their womb cells than women who had miscarriages. Since p16 is a marker of aging cells, this means more aging cells had more p16 — supporting the idea that senescent cells contain more p16.

Study: Impact of ER stress-regulated ATF4/p16 signaling on the premature senescence of renal tubular epithelial cells in diabetic nephropathy.

Scientists found that when kidney cells become old and stop working properly (senescent), they make a lot more of a protein called p16. This happened in both diabetic patients and lab-grown cells, so it’s a clear sign that senescent cells have more p16.

Study: Chronic social stress induces p16-mediated senescent cell accumulation in mice

The study found that when mice are stressed for a long time, their aging cells produce much more p16 protein — a sign those cells are worn out. This means senescent cells really do have more p16 than healthy cells.