Glucose metabolism and DNA methylation of offspring are altered by maternal sodium restriction

Abstract

Objective: To evaluate glucose metabolism of adult offspring of dams fed low sodium diet during pregnancy. Methods: Female Wistar rats (n= 6 – 8/group) were fed low (LS- 0.15%) or normal (NS-1.3% NaCl) salt diet since the 1st day of gestation until delivery or LS during 1st (LS10) or 2 nd half of gestation (LS20). Body weight (BW), circulating glucose, insulin, leptin and C-peptide levels, glucose (GTT) and insulin tolerance test (ITT) and leptin receptor (LR) methylation were measured in male (M) and female (F) offspring at 12 weeks of age Results (mean±SEM, p< 0.05): BW, at birth (g, n=14 – 27/group) (M: NS = 6.5±0.1, LS = 5.5±0.1, LS10 = 6±0.1, LS20 = 4.8±0.1, F: NS = 6±0.2, LS = 5±0.1, LS10 = 6±0.1, LS20 = 4±0.1) was lower in LS, LS10 and LS20 than in NS, while at adulthood it was not different. Glucose was higher in LS (M=115±3; F=110±4) than in the other groups (M: NS=103±1; LS10=100±2; LS20=96±2; F:NS=101±2; LS10=100±2; 108±2). C-peptide was higher in LS (M=1117±152; F=509±27) than in NS (M=375±41; F=233±63) and lower in LS20 (M=97±15; F=76±9) compared to LS10 (M=528±112; F=378±45).Glucose was higher in LS M and F at 5 minutes of the GTT compared to NS offspring. Leptin, insulin, and ITT were not different. But LR methylation was increased in LS20. Conclusion: Sodium restriction during pregnancy leads to low birth weight and to modifications of glucose metabolism and LR methylation.