Increase of Prostaglandin E2 in Reversal of Ductal Constriction After Dietary Restriction of Polyphenols

INCREASE OF PROSTAGLANDIN E2 IN REVERSAL OF DUCTAL CONSTRICTION AFTER DIETARY RESTRICTION OF POLYPHENOLS.

Fetal ductal constriction is a clinical situation with high morbidity and potential mortality. Patency the fetal ductus arteriosus (DA) depends on circulating prostaglandin (PG), which is produced by the cyclooxygenase (COX) pathway during inflammatory response(1) and from the third trimester of pregnancy on, is physiologically released. COX-inhibiting substances, such as nonsteroidal anti-inflammatory drugs (NSAIDs), can interfere with PG metabolism and induce constriction of the DA. To treat or prevent DA constriction, it is therefore important to reduce fetal exposure to drugs that may interfere with prostaglandin biosynthesis, such as natural anti-inflammatory drugs and polyphenol-rich foods.

Polyphenols, the most abundant antioxidants present in the diet, are widely distributed in vegetable foods. One of the possible mechanisms to explain their activity is inhibition of synthesis and release of inflammatory mediators. However, clinical studies investigating the effect of polyphenols on inflammatory responses are inconclusive and, in most cases, only evaluate clinical outcomes. The role of polyphenols on the inflammatory response, and associated modifications of the plasma concentration of PGE2 in pregnant women, has not yet been studied.

Despite the potential benefits of a diet rich in polyphenols, a high consumption of these substances in the third trimester of pregnancy may reduce plasma levels of PGE2 and result in DA constriction,so that a restriction in their ingestion during this period is already recommended.This functional problem has high prevalence and may result in severe fetal and neonatal complications. These considerations raised the hypothesis that reversal of fetal ductal constriction after maternal restriction of polyphenol-rich foods is accompanied by increased in prostaglandin E2 levels. Demonstration of this effect would represent an advancement in knowledge and might result in changes in dietary guidance during pregnancy and prevention of perinatal complications, with potential impact in terms of public health.

The aim of this study was to test the hypothesis that reversal of fetal ductal constriction in the third trimester of pregnancy, after maternal restriction of polyphenol-rich foods, is accompanied by increased plasma levels of prostaglandin E2.

Inclusion criteria

• Pregnancy with diagnosis of fetal ductal constriction
• Single fetus
• gestational age from 28 weeks

Exclusion criteria

• cardiac malformations
• restricted intrauterine growth
• increased nuchal translucency
• present or suspected chromosomal disorders
• signs of any type of hydrops fetalis
• pregnancy
• hypertension
• diabetes mellitus
• structural or functional cardiac disorders
• current use of nonsteroidal anti-inflammatory drugs, steroids, antidepressants, illicit drugs, alcohol or smoking
• multiple pregnancy
• having received previous nutritional guidance in relation to restricted intake of polyphenol-rich foods