Dynamic p53 protein expression and phosphorylation in the kidneys of rats that experienced intrauterine growth restriction

Abstract

Aim: This study investigated the mechanisms involved in intrauterine growth restriction (IUGR). Methods: The IUGR model was established by feeding pregnant SD rats a low-protein diet. Protein expression and phosphorylation were detected using Western blot and/or immunohistochemistry. Cell apoptosis was detected by TUNEL staining. The MDM2 mRNA expression was measured by real-time PCR. Results: Pups from the IUGR group had significantly lower body (7th day, 2 months) and kidney weights (1st day, 7th day, 2 months) compared to pups from the control group (p < 0.01). The glomeruli number in IUGR pups was significantly less than that in the control pups at 2 and 3 months after birth (p < 0.01). p53 protein level and p53 phosphorylation at Ser¹⁵ were time-dependently decreased in the kidney at 1st day, 7th day, 21st day, 2 months and 3 months, but their levels in the kidney of the IUGR pups was significantly higher than that in control pups at each time point (p < 0.05, p < 0.01, or p < 0.001). Significantly more positive p21 staining was observed in IUGR pups than in control pups at each time point. Real-time PCR of MDM2 mRNA expression showed no significant difference between IUGR and control pups (p > 0.05). Significant apoptosis was observed in the kidneys of IUGR pups compared to control pups. Conclusion: Malnutrition-induced IUGR may be associated with the activation of p53–p21 signaling in the kidney.

• Glomerular number
• intrauterine growth restriction
• kidney
• p53
• phosphorylation

Declaration of interest

The authors have declared that no conflict of interest exists.

This work was supported by the Second Xiangya Hospital of Endocrinology and Metabolism Research Center, Central South University.