Protein restriction during pregnancy affects lung development and promotes oxidative stress and inflammation in C57 BL/6 mice offspring.

Abstract

Objectives: The present study aimed to evaluate the effects of maternal protein restriction during pregnancy on the lungs of 1-d and 31-d old offspring of C57BL/6 mice. Methods: The C57BL/6 mice (810 wk) were used for breeding. After pregnancy confirmation, female mice

were randomly divided into a control group (CG) receiving a standard diet (22% protein) and a protein- restriction group (PRG) receiving a low-protein diet (6% protein). In the low-protein diet, protein was

replaced by carbohydrate. After parturition, female mice that received the low-protein diet were fed the standard diet. Male offspring were euthanized 1 d and 31 d after birth for subsequent analysis. We evaluated the effects of a protein-restricted diet during gestation in pulmonary organogenesis, lung oxidative stress, and pulmonary inflammatory response of the offspring. Results: PRG mice 1 d after birth showed lower body and lung mass, length, relative mass, lung density, and erythrocyte count compared with CG mice. There was an increase in alveolar airspace density and a higher mean linear intercept (Lm), greater oxidative damage, and inflammation in PRG mice compared with CG mice. At 31 d after birth, PRG mice had lower body mass, length, and lung mass values compared with CG mice. PRG mice showed greater recruitment of inflammatory cells to the airways. In addition, there was increased collagen deposition in the lungs, altered inflammatory mediators, and greater oxidative damage compared with CG mice.

Conclusions: Protein restriction during pregnancy reduces the body weight of offspring and promotes inflam- mation and oxidative stress, resulting in a simplification of the lung structure.