PathStAR, a framework quantifying tissue structural aging from routine histopathology images without being trained to predict chronological age, reveals that organ structural aging progresses via distinct, nonlinear temporal trajectories and coordinated deterioration within individuals across 40 tissues in 970 donors.
Key Findings
Methods
PathStAR successfully quantifies tissue structural aging from routine histopathology images across 40 tissues without being trained to predict chronological age.
The framework was applied to 25,306 post-mortem biopsies from 970 donors aged 21–70 years.
PathStAR analyzes histopathology images to capture changes in cell organization, vasculature, and extracellular matrix.
The approach does not rely on supervised training on chronological age labels, distinguishing it from conventional aging clocks.
Coverage spanned 40 distinct tissue types across the human body.
Results
Vascular tissue structural aging accelerates early in the human lifespan.
Vascular tissues showed early-onset acceleration in structural aging trajectories compared to other organ systems.
This pattern was identified through nonlinear trajectory modeling of structural aging scores across the 21–70 year age range.
The finding suggests vascular structural deterioration begins relatively early in adulthood.
Results
Uterus and vagina structural aging accelerates late, approximately around the time of menopause.
Structural aging in uterus and vagina showed a late-onset acceleration pattern.
The acceleration timing corresponds roughly to menopausal transition.
This late acceleration distinguishes reproductive tissues from other organ systems examined.
Results
Digestive and male reproductive organs exhibit biphasic accelerations in structural aging.
Certain tissues including digestive and male reproductive organs show two distinct phases of accelerated structural aging.
This biphasic pattern was identified as a distinct trajectory type among the nonlinear aging patterns observed.
The pattern suggests these tissues undergo two separate periods of heightened structural change across the adult lifespan.
Results
Accelerations of structural aging are characterized across organs by increased inflammation alongside reduced energy production, repair, and quality control.
Molecular characterization of structural aging acceleration phases revealed consistent biological signatures across multiple organ systems.
Increased inflammation was identified as a universal feature of structural aging acceleration.
Reduced energy production, repair mechanisms, and quality control processes accompanied structural aging accelerations.
These molecular features were identified across organs, suggesting shared biological underpinnings of structural deterioration.
Results
Cross-organ analysis reveals coordinated structural deterioration within individuals, particularly linking digestive and male reproductive tissues through sex hormones.
Structural aging was not independent across organs within the same individual; coordinated deterioration patterns were detected.
Digestive and male reproductive tissues showed a particularly notable coordinated aging relationship.
Sex hormones were implicated as a linking mechanism underlying the coordinated deterioration between these tissue groups.
This finding suggests systemic or hormonal factors contribute to multi-organ aging coordination.
Results
Organ structural aging progresses via distinct, nonlinear temporal trajectories rather than uniform linear decline.
Analysis of 40 tissues revealed multiple distinct trajectory types, including early acceleration, late acceleration, and biphasic acceleration.
The nonlinear nature of trajectories was identified across the donor age range of 21–70 years.
Different organs follow fundamentally different aging timelines, rejecting a one-size-fits-all model of structural aging.
The systematic mapping provides what the authors describe as 'a systematic map of structural aging across the human body.'
What This Means
This research suggests that the physical structure of our organs — how cells are arranged, how blood vessels are organized, and how the scaffolding between cells is maintained — changes with age in very different ways depending on which organ you look at. The researchers developed a computer-based tool called PathStAR that can measure how 'structurally old' a tissue looks by analyzing standard microscope images of tissue samples, without simply being taught to guess a person's age. They applied this tool to over 25,000 tissue samples from nearly 1,000 people aged 21 to 70 across 40 different organ types.
The findings reveal that structural aging does not happen at the same pace or at the same time across all organs. Blood vessel tissues begin deteriorating structurally relatively early in adult life, while the uterus and vagina show a sharp acceleration in structural aging around midlife, coinciding with menopause. The digestive system and male reproductive organs show an unusual pattern with two separate bursts of accelerated aging across the lifespan. When the researchers looked at the biology underlying these acceleration periods, they consistently found signs of increased inflammation and decreased ability to produce energy, repair damage, and remove waste — regardless of which organ was examined. They also found that aging in some organs is coordinated with aging in other organs within the same person, particularly between the digestive system and male reproductive organs, with sex hormones appearing to play a connecting role.
This research matters because it provides the first large-scale, systematic picture of how tissue structure deteriorates across the entire human body over time. Understanding that different organs age at different rates and through different patterns could help explain why some age-related diseases emerge earlier or later in life, and why some people seem to age faster in certain organ systems than others. The tool developed here could eventually help identify individuals whose organs are aging unusually quickly, opening the door to earlier intervention strategies.
Yadav A, Alvarez K, Chechenina A, Yip K, Ruppin E, Colas A, et al.. (2026). Mapping structural aging across human tissues reveals tissue-specific trajectories and coordinated deterioration.. Nature aging. https://doi.org/10.1038/s43587-026-01200-4