Congenital diaphragmatic hernia and retinoids: searching for an etiology

Congenital diaphragmatic hernia (CDH) is a major life-threatening cause of respiratory failure in the newborn. Recent data reveal the role of a retinoid-signaling pathway disruption in the pathogenesis of CDH. We describe the epidemiology and pathophysiology of human CDH, the metabolism of retinoids and the implications of retinoids in the development of the diaphragm and lung. Finally, we describe the existing evidence of a disruption of the retinoid-signaling pathway in CDH

Effect of nitrofen in the final stages of development of the diaphragm muscle in rats

PURPOSE: To evaluate the expression of myosin in muscle fibers of the diaphragm in experimental congenital diaphragmatic hernia (CDH). METHODS: Fetuses of pregnant rats were divided into four groups: External Control (EC), composed of non-manipulated rats; Nitrofen, composed of pregnant rats that received 100 mg of nitrofen (2,4-dichloro-4'nitrodiphenyl ether) diluted in olive oil on gestational day (GD) 9.5, whose fetuses developed CDH (N+) or not (N-), and Olive Oil Placebo (OO), composed of pregnant rats that received the oil on the same GD. The fetuses were collected on GD 18.5, 19.5, 20.5 and 21.5 (term = 22 days). We obtained body weight (BW) and photographed the diaphragm area (DA), hernia area (HA) and subsequent calculated the HA/DA ratio in N+ group. Samples of Diaphragm muscle were processed for histological staining with H/E and immunohistochemistry (IHQ) for myosin.} RESULTS: The fetuses of N- and N+ groups had decreased BW and DA compared to EC and OO groups (p <0.001). HA was decreased on GD 18.5 compared to 21.5 (p <0.001) and the HA/DA ratio showed no difference. IHQ showed decreased expression of myosin in nitrofen groups. CONCLUSION: CDH induced by nitrofen model contributes to the understanding of muscularization in the formation of the diaphragm where the myosin expression is decreased