Fig. 2. Aberrant levels of lipid species are involved in CKD.

a Heatmap clustering analysis based on 50 lipid species between the two groups. b Dendrogram of hierarchical clustering analysis of 50 lipid species between the two groups. c PCA of 50 lipid species between the two groups. d OPLS-DA of 50 lipid species between the two groups. e Summary of ingenuity pathway analysis with lipidomics pathway analysis. f Lipid species set enrichment overview. The size and colour of each circle are based on the enrichment ratio and P values, respectively. The enrichment ratio was calculated by hits/expected, where hits = observed hits and expected = expected hits.