Impact of Oxidative Stress on Maternal Serum Apelin 13 and Endothelial Nitric Oxide Synthase in Preeclampsia.

Abstract

Preeclampsia (PE) is the most common hypertensive disease of pregnancy, leads to maternal, perinatal morbidity and mortality, which accounts for 2-8% of pregnancies. Preeclampsia is characterized by new onset of hypertension and proteinuria after 20 weeks of gestation.The exact cause of preeclampsia is not clear. Aim of this study is to investigate the association between maternal serum apelin13, endothelial nitric oxide synthase, markers of oxidative stress in healthypregnant womenand preeclamptic women. This prospective studycomprises 140 pregnant womenconsists of 70 preeclamptic women treated as cases and 70 normotensive healthy pregnant women as controls. Five mL blood sample was collected, centrifuged to obtain serum/plasma and was stored at -80°C for further testing. Plasma was used for Ferric reducing antioxidant power (FRAP) assay and complete blood countwas done. Routine parameters like random blood sugar, renal profile, liver enzymes, lactate dehydrogenase (LDH), malondialdehyde (MDA), nitric oxide (NO), apelin 13 and endothelial nitric oxide synthase (eNOS)were also analyzed. Corresponding urine sample was tested for protein. Study results showed lower gestational age (36.99±3.48 weeks) and demographic details such as elevated blood pressure [systolic (156.80±13.71 mmHg),diastolic (101.97±10.70 mmHg),and mean arterial pressure (120.88±11.02 mmHg)], BMI (27.42±3.80 kg/m2) and pulse rate (87.68±5.74 bpm) were observed in cases than controls. The biological markers namely serum MDA (18.57±7.52ìmoles/L) levels were significantly increased and nitric oxide (6.47±1.22ìmoles/L), FRAP (1292.10±525.38 mmol/L), apelin 13(312.42±189.00pg/ml) andeNOS(5.07±2.30 ng/ml)levels were significantly decreased in cases.Mean arterial pressure was negatively correlatedwithApelin 13 (r=-0.179), NO (r=-0.065), FRAP (r=-0.169), and birth weight (r=-0.281) and eNOS (r= 0.013), MDA (r= 0.022) were positively correlated with mean arterial pressure. The study concludes that reduced levels of apelin 13, eNOS, FRAP,NO and high oxidative stress, contribute to pathogenesis of preeclampsia and adverse perinatal outcome. It also demandssufficient evidence for the functional role of apelin 13 as a target in hypertension regulation.