Research Paper Advance Articles

Figure 4. Age-specific plasma exosome protein signatures in old and young cohorts. (A) Partial least squares-discriminant analysis (PLS-DA) clustered old and young cohorts based on 1356 protein groups. The two variates explaining the most significant variations are shown. (B) Volcano plot showing significantly altered age-specific plasma exosome proteins (q-value < 0.05 and ≥ 1.5-fold). Red, upregulated; Blue, downregulated; and Gray, No significant change. A few selected differentially abundant proteins are labeled. (C) Heatmap displaying the plasma exosome protein fold change averaged across replicates, showing the top 26 altered proteins increased (red) and decreased (blue) due to Aging. The intensities averaged for young plasma exosomes were used as the baseline. ClueGO biological pathways and cell compartments are presented. BP; Biological process, CC; Cellular compartment. P-value * ≤ 0.05, ** ≤ 0.01, *** ≤ 0.001. (D) The most significant age-related exosome protein pathways are (i) upregulated and (ii) downregulated. (E) Enrichment analysis of gene-ontology/cellular compartments overrepresented among aging exosome proteins. (F) Three examples of individual protein MS intensities and how the intensity changes with age.