Maternal nutrient restriction alters renal development and blood pressure regulation of the offspring

Abstract

Studies have shown that the risk of hypertension in adulthood can be affected by the in utero environment. It is established that hypertension is linked to compromised kidney function and that factors affecting organogenesis can increase the risk of later disease. Prostaglandins (PG) and growth factors are known to play an important role in regulating kidney function and renal organogenesis. The extent, however, to which global energy restriction (where all nutrients are reduced) of the mother can programme later blood pressure control or renal PG and growth factor status is unknown. A study is described that aimed to examine the long-term effects of maternal nutrient restriction (NR) and elucidate their relationship with compromised kidney development. First, it was necessary to establish animal models. A sheep model of 50% NR during specific stages of gestation was used to investigate fetal renal development, whilst a rat model of 50% NR throughout pregnancy was used to investigate postnatal kidney development and adult functioning. Molecular analysis has shown that expression of the growth hormone-insulin-like growth factor (GH-IGF) axis is affected by NR in the fetal sheep kidneys, and that changes are dependent on the timing of NR and whether the fetus is a singleton or a twin. Analysis of the kidneys from the rat model has shown nutritional differences in the expression of PG receptors and the enzymes responsible for PG synthesis and degradation that persist into adulthood. In conclusion, NR does affect the GH-IGF and PG axes, and these changes may be important in the nutritional programming of renal functioning and adult blood pressure control.