Interplay of oxidative stress and nitric oxide synthase gene expression on cardiovascular responses in preeclampsia

Abstract

Background: Pre-eclampsia (PE) is a major complication of pregnancy that could lead to maternal and fetal morbidity and mortality. There are possible genetic, immune, and vasoactive factors implicated in the vascular dysfunction associated with PE, which may thereby cause cardiovascular and renal pathology. Aim: To determine NOS gene expression in circulation and its relationship with cardiovascular and renal functions and anti-oxidant status. Methods: This was a case-control study conducted in a tertiary care centre of North Karnataka, India. Institutional Ethics committee clearance was obtained and informed consent was obtained from all the participants. Thirty cases of pre-eclampsia and thirty normal pregnancy controls were included. Blood pressure, heart rate and heart rate variability were recorded. Whole blood was analyzed for NOS 3 gene expression by RT-PCR and serum for total antioxidant capacity. Data was analyzed using the Student's t test. P-value < 0.05 will be considered statistically significant. Results: The total antioxidant capacity of cases with pre-eclampsia was reduced significantly. NOS 3 gene expression was reduced in these cases. The mean arterial blood pressure and also LF/HF ratio of heart rate variability analysis increased in the cases. Conclusion: Oxidative stress with consecutive reduced antioxidant capacity may lead to down-regulation of NOS3 gene expression, which in turn, may affect systemic cardiovascular functions in preeclampsia.

Keywords

• oxidative stress
• endothelial nitric oxide synthase
• gene expression