GCG and type 2 diabetes mellitus: The DEPs between the T2DM and normal groups were significantly enriched in pathways involved in the insulin signaling pathway, glucagon signaling pathway, cholesterol metabolism, fat digestion and absorption, carbon metabolism, AMPK signaling pathway, glutathione metabolism, vitamin digestion and absorption, tryptophan metabolism, etc. (Fig. 7C). And the DEPs between the MLE and T2DM groups were highly enriched in pathways involved in PPAR signaling pathway, cholesterol metabolism, fat digestion and absorption, vitamin digestion and absorption, and so on (Fig. 7D).