Polyphenol-rich food general and on pregnancy effects: a review.

This review aimed to investigate possible protective or deleterious effects of polyphenol-rich foods (PRF) on chronic diseases, e.g. cardiovascular, and in pregnant women, along with their antioxidant and anti-inflammatory action. A great variety of foods and beverages, such as herbal teas, grape and orange derivatives, dark chocolate, and many others contain high concentrations of flavonoids and are freely consumed by the general population. In humans, PRF consumption reduces lipid peroxidation, and several studies have shown a positive correlation between an increased consumption of PRF and a decrease in the incidence of cardiovascular disease. On the other hand, current studies have suggested that maternal ingestion of PRF, especially during the third trimester of pregnancy, could be associated to fetal ductal constriction (DC). Fetuses exposed to this type of diet show higher ductal velocities and lower pulsatility indexes, as well as larger right ventricles than those exposed to minimal amounts of these substances. The underlying mechanism involved in these conditions has not been entirely elucidated, but it seems to be a result of the antioxidant and anti-inflammatory effects of polyphenols by some pathway. Furthermore, taking into account the deleterious effect in late-pregnancy against the numerous positive effects associated to polyphenols, this dual behavior deserves attention particularly to control the dietary ingestion of PRF during gestation. In this line, same PRF, natural constituents of human diet, may represent risk to fetal in late pregnancy compared to the use of nonsteroidal anti-inflammatory drugs.

Effects of bone disease and calcium supplementation on antioxidant enzymes in postmenopausal women.

OBJECTIVES: The study was aimed at investigating the effects of osteopenia and calcium supplementation on antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; and glutathione peroxidase, GPx) in postmenopausal women. DESIGN AND METHODS: Postmenopausal women (n=75) were divided into two groups, control (no bone disease) and osteopenia, according to their bone mineral density. Each group was still divided into calcium-supplemented and nonsupplemented sub-groups. Antioxidant enzyme activities were determined in whole blood using spectrophotometric methods. RESULTS: CAT and SOD activities were not different among the studied groups. However, GPx activity was significantly higher in osteopenia groups as compared to control groups. Calcium supplementation had no effect on the parameters evaluated. Bone mineral density was negatively correlated with GPx activity (p<0.05). CONCLUSIONS: Increased GPx activity could be interpreted as a defense response to counteract the overproduction of reactive oxygen species in women with osteopenia, and this effect was not prevented by calcium supplementation.