The human body doesn't age at a single, steady pace. Instead, each organ follows its own timeline, and organs that age quickly tend to have "aging partners" that speed up in sync, according to a new study that mapped structural aging across 40 types of tissue.
For the study, published in Nature Aging, researchers at Sanford Burnham Prebys Medical Discovery Institute built a deep-learning computer vision model called PathStAR to analyze more than 25,000 scanned tissue biopsy images from nearly 1,000 deceased donors. PathStAR segmented the images into more than 30 million smaller patches and extracted features reflecting underlying tissue structure to chart how each organ's structure changes over time—without needing to be told a sample's chronological age.
The team first tested the model on 250 ovarian tissue images from donors aged 21 to 70, finding that ovaries age in two accelerated bursts: one from ages 35 to 40, coinciding with fertility decline, and another from 55 to 60, corresponding to post-menopause.
After narrowing the broader dataset to 15 tissue types with enough samples across the lifespan, the researchers found tissues fell into three patterns. Vascular tissue aged fastest early, from ages 30 to 39, then slowed. Late-aging tissues, including the uterus and vagina, stayed relatively stable in early adulthood before aging rapidly from ages 50 to 55. Most tissues, however, followed the ovaries' biphasic pattern, aging in two distinct bursts.
Across all three patterns, periods of accelerated aging shared a common molecular signature: heightened expression of inflammation-related genes alongside suppressed genes governing energy production, cell growth and cellular quality control.
"Our goal is to understand how aging occurs at a structural level," said Sanju Sinha, assistant professor in the Center for Data Science and Artificial Intelligence at Sanford Burnham Prebys. "This is a public dataset used by hundreds of groups, but nearly everyone uses the molecular data. There are tens of terabytes of imaging data that have gone nearly untouched."
Because more than half of the tissues studied echoed the ovaries' aging pattern, the researchers believe the ovaries may act as a kind of pacemaker for aging throughout the body, hinting that hormonal signaling could help coordinate the process.
Sinha said the findings could lay the groundwork for a broader structural aging atlas to guide the design of organ-specific anti-aging treatments, and that therapies aimed at protecting reproductive aging might help extend the healthy lifespan of other organs as well.
Data from Sanford Burnham Prebys