Composition of the whole transcriptome in the human plasma: Cellular source and modification by aging

Area of Science:

• Molecular Biology
• Genomics
• Aging Research

Background:

• Plasma extracellular vesicles (EVs) contain bioactive molecules like RNA, DNA, proteins, lipids, and metabolites.
• These molecules mediate cell-to-cell communication and influence recipient cell functions.
• Extracellular RNA (exRNA) in plasma is a potential biomarker for biological processes.

Purpose of the Study:

• To investigate the cellular origin of mRNA transcripts found in human plasma exRNA.
• To analyze aging-associated changes in plasma exRNA composition and their functional implications.

Main Methods:

• RNA-sequencing of plasma exRNA from healthy individuals.
• Comparison of plasma exRNA profiles with peripheral blood mononuclear cells (PBMCs) from the same individuals.
• Gene ontology enrichment analysis and differential expression analysis to assess aging effects.

Main Results:

• A substantial proportion of plasma exRNA transcripts originate from non-PBMC cell types.
• Gene ontology analysis revealed age-related functional decline in biological processes.
• Differential expression analysis identified 10 transcripts with significant aging-associated changes in plasma.

Conclusions:

• Plasma exRNA is not solely derived from PBMCs; other cell types contribute significantly to its composition.
• Aging induces notable alterations in plasma exRNA content, affecting critical biological pathways.
• Plasma exRNA serves as a valuable indicator of both cellular origin and age-related biological changes.