PPARA and diabetic kidney disease: In the DKD and HC groups, we selected five meaningful pathways, which were Alanine, Aspartate and glutamate metabolism, Pyrimidine metabolism, peroxisome proliferator‐activated receptor (PPAR) signaling pathway, Janus kinase‐signal transducer and activator of transcription (JAK‐STAT) signaling pathway and Histidine metabolism.