The expression of kidney injury molecule-1 (KIM1, p < 0.05) and leucine-rich alpha-2-glycoprotein 1 (LRG1, p < 0.01) was significantly higher in the preterm control group than in the preterm IGF-1 and term groups on PND5 (Fig. 4a, b), suggesting potential protective effects of IGF-1 against preterm birth-related kidney injury. This evidence concerns the gene HAVCR1 and kidney injury.