The results revealed that a circulating and abundant modified glycated human serum albumin protein in diabetic patients induced a sustained reactive oxygen species production in human endothelial cells. This effect may have been due to an up-regulation of Nox4, the main subunit of NADPH oxidase in the endothelium.

Endothelial dysfunction has been linked to reactive oxygen species (ROS) production by nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase. Angiotensin II (ANG), which levels are elevated in some cardiovascular diseases, can stimulate this enzyme, whereas statins have been demonstrated pleiotropic effects related with the restoration of endothelial function. Therefore, our purpose was to study the mechanism of the possible beneficial effects of pravastatin on ANG-activated human umbilical vein endothelial cells (HUVEC). ANG induced an increase in the extracellular superoxide anion produced by NADPH oxidase but had no effect in the intracellular ROS production. Pravastatin, which alone did not have any effect on ROS production, totally blocked the stimulating effects of ANG when combined with it. These effects were not due to a direct action of ANG or pravastatin on the activity of NADPH oxidase measured in HUVEC lisates. On the contrary, the results correlated well with other effects of ANG: a Nox4 and p22phox upregulated expression and an enhanced Nox4 translocation to the cell membrane. All these effects were inhibited by pravastatin, which had no effect when incubated alone. These data reveal for the first time that pravastatin interrupts the signaling pathway activated by ANG that leads to an enhanced NADPH oxidase activity at the cell membrane of HUVEC. For that, pravastatin inhibits ANG-induced upregulation of catalytic NADPH oxidase subunits and blocks the migration of them to the endothelial cell membrane.

Procyanidins have been associated with a reduced risk of cardiovascular diseases such as atherosclerosis. However, the molecular mechanisms underlying this benefit are not fully understood. Increased reactive oxygen species (ROS) production generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is a common problem in different cardiovascular diseases. Our objective was to evaluate the effects of procyanidin-rich fractions from distilled grape pomace on NADPH oxidase activity in human umbilical vein endothelial cells (HUVEC). Three differently polymerized and galloylated procyanidin fractions were analyzed for their NADPH oxidase inhibitory activity in cell lysates and in HUVEC cultures. All of the three fractions, up to 1 µg/ml, equally inhibited isolated NADPH oxidase in HUVEC lysates in a concentration-dependent manner and independently of any superoxide anion scavenging activities. The procyanidin fractions even blocked NADPH oxidase activity in intact HUVEC, inhibiting ROS production at both extra- and intracellular levels. The fractions achieved the same effects that known NADPH oxidase inhibitors, such as diphenylene iodonium and apocynin, but they presented better hydrosolubility. Our results demonstrated that procyanidin from grape pomace inhibit human endothelial NADPH oxidase regardless of their polymerization degree and galloylation percentage. Therefore, procyanidins are suitable NADPH oxidase inhibitors which could serve as models for therapeutic alternatives for cardiovascular diseases.

We report the case of a fetus aborted at gestation week 20 because of hydranencephalic-hydrocephalic syndrome. The fetus was the third pregnancy of a nonconsanguineous couple whose first child exhibited congenital hydranencephalic-hydrocephalic syndrome associated with muscle histology findings consistent with mitochondrial cytopathy and deficiency of complexes III and IV of the respiratory chain and whose second pregnancy had terminated in an elective abortion on detection of progressive hydrocephalus at gestation week 19. The third pregnancy had a normal course according to obstetric and ultrasonography examinations performed at gestation weeks 5, 10, and 15, and negative results were obtained in standard serologic and polymerase chain reaction (PCR) tests for prenatal infections of the mother. However, the ultrasonography examination at gestation week 18 revealed hydrocephalus, in response to which the parents requested an abortion, which was performed at gestation week 20; the fetus was male and with no evident external malformations. Histopathologic studies of the brain and medulla oblongata revealed proliferative vasculopathy (glomeruloid vessels, intracytoplasmic inclusions, and microcalcifications) and intracytoplasmic inclusions in the voluntary muscle. Microbiologic and PCR tests of hepatic and spleen tissue were negative for prenatal infections. In view of the precedent of a sister with mitochondrial dysfunction, these findings raise the pos sibility that at least some cases of familial syndrome of congenital hydranencephalic-hydrocephalic syndrome with proliferative vasculopathy can be attributed to alterations in the mitochondrial respiratory chain.