Fig. 1: scRNAseq revealed differences between astrocytes from young and aged mice.

a Schematic of the approach to evaluate astrocytes within the striatum in young and aged mice (n = 4 mice per group, 8 total; 64,836 cells). The cartoons on the left side of (a) were created in Biorender (Linker, K. (2025) https://BioRender.com/4yka9a8). b UMAP split by age and molecular identity. c A violin plot of select markers for each major cell type (ASC astrocyte, MG microglia, OLG oligodendrocyte, NEU neuron, NSC neural stem cell, EC endothelial cell, OPC oligodendrocyte precursor cell, MC mural cell, EP ependyma cell) is shown (cross-referenced with dropviz.org) (c). The astrocyte cell class was subset from the larger dataset and analyzed further (d–f). d UMAP of astrocytes, which shows putative subtypes identified with Louvain clustering (resolution = 0.1), split by molecular identity and age. e The number of each cell type derived from young (green) or old (red) for each astrocyte subtype (A1–7) is shown to display the contribution of young or aged cells to each astrocyte subcluster. The relative percentage of each astrocyte subcluster commits to the total amount of astrocytes (e, inner pie) and if the subcluster is dominated by cells from aged, young, or neither (common) samples (e, outer pie). Astrocyte subclusters were determined to be young or aged dominant if >70% of the cells within that cluster came from young or aged mice. Expression of 10 distinct subtype-defining markers for each subcluster is shown (f). g FPKM from the Chai et al.²⁰ RNAseq dataset is shown in the grayscale heatmap. The average raw count values of cluster-defining genes in the Jin et al.⁴¹ single-cell sequencing of astrocytes are shown in the orange heatmap. h Astrocytes and endothelial cells contribute the highest amount of DEGs to the total aging DEGs across all cell types. i UMAP of subset endothelial cells have nine unique molecular subtypes that were identified with Louvain clustering (resolution = 0.1). j The number of each cell derived from young or old for each endothelial subtype (E1–9) is shown to display the contribution of young or aged cells to each endothelial subcluster. The relative percentage of each endothelial subcluster (j, inner pie) and if the subcluster is dominated by cells from aged, young, or neither (common) samples (j, outer pie).