Role of PERK-eIF2α signaling pathway in fetal male rats with hypospadias induced by di-n-butyl phthalate

Abstract

This study aims to explore the role of PERK-eIF2α signaling pathway in fetal male rats with hypospadias induced by maternal exposure to di-n-butyl phthalate (DBP). DBP was used to treat pregnant SD rats by gastric intubation from gestation day (GD) 14–18 to construct a hypospadias rat model. The amount, weight, anogenital distance (AGD), and hypospadias incidence of rats were recorded and the genital tubercle (GT) of fetal male rats was collected on GD 19. Western blotting was performed to detect the expressions of PERK-eIF2α pathway- and autophagy-related proteins, and cell apoptosis was detected using TUNEL method. Then, GT fibroblasts of fetal rats were obtained and transfected with PERK-siRNA to detect cell apoptosis and autophagy in each transfected group. The incidence of hypospadias was 43.49% in fetal male rats induced by DBP. The fetal rats in DBP group presented the decreased birth weight and anogenital distance (AGD)/body weight ratio than the Control group (all P < 0.05). Further, p-PERK, p-eIF2α and ATF4 protein expressions and the ratio of LC3-II/LC3-I were greatly increased in the GTs of fetal rats, while apoptosis index (AI) and P62 protein expression were evidently decreased (all P < 0.05). In addition, the apoptosis rate was increased in GT fibroblasts after transfection of PERK-siRNA with the increased P62 and reduced LC3-II/LC3-I ratio (all P < 0.05). Activation of PERK-eIF2α signaling pathway can influence the GT development of fetal male rats with hypospadias induced by DBP through activation of autophagy and inhibition of apoptosis.