Transcriptome States Reflect Imaging of Aging States.

Area of Science:

• Gerontology
• Developmental Biology
• Molecular Biology

Background:

• Aging is a complex process with variations in lifespan and health.
• Understanding age-related changes at a molecular and morphological level is crucial.
• Previous research has linked transcriptome profiles to age-matched animals in different states.

Purpose of the Study:

• To describe a novel morphological biomarker for identifying distinct age-states in Caenorhabditis elegans.
• To characterize the transitions between these age-states across the lifespan.
• To investigate the relationship between age-states, lifespan, and gene expression.

Main Methods:

• Utilized a morphological biomarker to classify nematodes into discrete age-states.
• Analyzed state frequencies and transition timing across the lifespan in short-lived and long-lived strains.
• Performed microarray analysis on animals isolated at different stages of identified age-states.
• Applied principal component analysis, distance measurements, and gene set enrichment analysis.

Main Results:

• Identified three healthy adult age-states with distinct transition timings.
• Revealed that long-lived strains favor healthy states, while short-lived strains transition rapidly.
• Demonstrated that age-states provide a novel assessment of aging, distinct from chronological age.
• Observed later expression of hsp70 and small heat shock protein genes, aligning with proteostasis collapse models.

Conclusions:

• A morphological biomarker can effectively distinguish age-states in Caenorhabditis elegans, offering a new perspective on aging.
• Age-states are associated with differences in lifespan and gene expression, particularly concerning heat shock proteins.
• This approach complements chronological age, providing a more nuanced understanding of the aging process.