Changes of Clara cell protein and interferon-γ in lungs with fetal growth retardation in fetal rats / 中华实用儿科临床杂志

ABSTRACT

Objective To determine the effects of intrauterine growth retardation(IUGR) caused by malnutrition during pregnancy on the lung structure and expression of Clara cell protein (CCSP) and interferon (IFN)-γ in the fetal lungs,and to explore their relation ship with pulmonary disease.Methods Fetal rats from maternal protein-malnutrition dams were studied on day 20(term 21.5 day).The lung pathology was examined by means of Hematoxylin and eosin(HE) stain.Plasma was collected to determine the CCSP and IFN-γ concentration.Lungs were harvested to measure the expression of CCSP and IFN-γ mRNA by using fluorescent quantization reverse transcription (RT)-PCR and the levels of CCSP and IFN-γ protein were assessed by using enzyme-linked immunosorbent assay.Results Malnutrition fetus body weight significantly less compared to control group,so did the lung weight.However,lung weight,expressed as a percentage of body weight between the 2 groups was not different.The IUGR group had significantly decreased alveolar number manifested by lower radial alveolar count,and significantly increased mean linear intercept of alveoli.Both the CCSP mRNA expression and protein level in lung of IUGR rats were decreased compared with control rats (all P ＜ 0.05).A decline in plasma CCSP protein concentration was also noted compared with control group (P ＜0.05).Furthermore,IUGR group fetus showed lower IFN-γ levels both in circulation and in the lung tissue (all P ＜ 0.05).Conclusions Intrauterine malnutrition significantly alters lung structure and cytokine IFN-γ level,and the latter may further inhibit the transcription of CCSP gene.These alterations may contribute to both early and late postnatal respiratory morbidity.