Anti-oxidants correct disturbance of redox enzymes in the hearts of rat fetuses with congenital diaphragmatic hernia

Abstract

Aim: To evaluate if the redox system is unbalanced in the hearts of nitrofen-induced congenital diaphragmatic hernia (CDH) animals and to study the possible preventive effects of two anti-oxidant treatments, apocynin and epigallocatechin-3-gallate (EGCG).

Methods: Adult rats were divided into four groups. Group 1: rats received only vehicle on day E9.5. Group 2: rats received 100 mg nitrofen on day E9.5. Group 3: 1 month before mating rats received apocynin 1.5 mM and, when pregnant, 100 mg nitrofen on day E9.5. Group 4: same than group 3 but with EGCG 30 mg/kg. All fetuses were recovered at term and the hearts were processed. Nox activity and mRNA levels of Nox1, Nox2, Nox4, SOD1, SOD2, SOD3, catalase, and GPX1 were analyzed. Nox, SOD, and Catalase activity and H2O2 production were also evaluated.

Results: Nox activity, H₂O₂ production and Nox1, Nox2, and Nox4 mRNA levels were increased in the hearts of fetuses with CDH. There were no changes in SOD1 levels, whereas those of SOD2, SOD3, catalase, and GPX1 mRNA were decreased. Apocynin and EGCG treatments attenuated the increment of Nox and SOD activities and H₂O₂ production was only decreased by apocynin.

Conclusion: These findings suggest a possible preventive effect on the abnormal redox metabolism of anti-oxidant treatments in the hearts from rat fetuses with CDH. If the same occurs in humans, it could represent a potential tool in future prenatal treatment.

Keywords: Anti-oxidants; Apocynin; Cardiac malformations; Congenital diaphragmatic hernia; Epigallocatechin-3-gallate; Nitrofen; Pulmonary hypertension; Redox metabolism.