Fig. 2

The identification of differential metabolites. Volcano plot shows the differential metabolites between old and control groups (A), DOR and control groups (B), scPOI and control groups (C), POI and control groups (D). Comparing to the control group, the up-regulated and down-regulated metabolites were marked in red and blue, respectively. (E) The heatmap analyzes hierarchical clustering of the top 10 differential metabolites in all groups