In line with the observation in the T2DM contexts, FGF21 treatment also significantly improved the blood perfusion in the ischaemic mouse tissues of compared with that in the PBS‐treated control mice since day 14 post‐HLI surgery (Figure 2A,B), which was accompanied by significantly higher CD31‐positive capillary staining (Figure 2C,D), and an apparent increase in CD31 protein expression (Figure 2E,F) in the ischaemic muscle of FGF21‐treated mice. The gene discussed is PECAM1; the disease is type 2 diabetes mellitus.