FOXO1 and diabetic kidney disease: Since PGRN induced the expression of Sirt1 and reduced the acetylation levels of PGC-1α and FoxO1 in HG-treated podocytes, it suggests that PGRN modulates mitochondrial biogenesis and mitophagy through Sirt1-PGC-1α/FoxO1 signaling and thus protects against podocyte injury in DKD (Zhou et al., 2019).