A possible beneficial effect of selenium administration in antiarrhythmic therapy

Quibus cor palpitet: Hyena cor

The search for a genuine thought in ancient times makes medical archeology part of our contemporary knowledge, not to say a patrimony to be harbored. A Roman encyclopedia is a compilation of the prevailing knowledge of scientific and medical matters at the time. In this paper an original Roman prescription for a specific cardiac complaint is analyzed for its activity and efficaciousness. Further investigation of the effect of Selenium administration is warranted.

Antioxidant levels in the cord blood of term fetus

The aim of this study was to compare the differences in the total antioxidant levels in the cord blood after a normal vaginal delivery and after an elective caesarean section. This was a prospective study approved by the Wirral Hospital ethical research committee. The study was carried out in a district general hospital. We investigated 96 healthy pregnant women who had normal antenatal period with singleton pregnancies between 37 and 42 completed weeks of gestation. Sixty-five women had a spontaneous normal vaginal delivery and 31 underwent elective caesarean section. Umbilical cord blood was obtained immediately after delivery. Antioxidants such as glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured and compared between the normal vaginal delivery and elective ceasarean sections. The mean values for GPx in umbilical cord arterial blood (95; 86-103, n=74) was found to be significantly higher (P=0.0133) than that found in umbilical cord venous blood (84; 80-88, n=95). The arterial SOD values were found to be significantly higher (P=0.0337) in infants who had been delivered by caesarean section (1188; 1065-1311, n=22) than by vaginal delivery (1021;958-1083, n=39). The differences in the levels of GPX between the arterial and venous systems is not well documented but may be due to differences in the level of selenium, hydroperoxides or glutathione. In addition, why infants delivered by ceasarian section have a higher level of arterial SOD than those delivered by vaginal delivery remains unclear, but it may be a reflection of a relatively low level in infants subjected to the stress of labour.

Oral nutritional supplements and heart disease: a review

The use of nutritional supplements in the treatment of cardiovascular disease is rapidly growing in the United States. Many substances are marketed with anecdotal claims of efficacy. Most have not been scientifically studied. Excitement exists in the lay press about the homocysteine hypothesis of coronary artery disease and vitamin cures. A MEDLINE search and review of papers covering the study of popular nutritional supplements were undertaken. The papers were limited to peer-review journals using patient series reports, double-blinded prospective studies, and population studies. A compendium of the available data was obtained and an analysis of each paper's methodology was done. A review of the most popular and most studied oral nutritional supplements for the treatment of heart disease demonstrated relatively few well-founded indications for the widespread application of substances with the exception of the bioflavonoids. Some modest effects for endothelial dysfunction were noted for vitamins C and E. Red wines and beers were also noted to be beneficial. The majority of substances either had no effect or were deleterious.

Protective effect of gamma-glutamylcysteinylethyl ester on dysfunction of the selenium-deficient rat heart

We investigated the protective effect of intracellular GSH against cardiac dysfunction in selenium (Se)-deficient neonatal rats and cultured fetal rat myocytes. A Se-deficient diet with or without daily subcutaneous injections of gamma-glutamylcysteinylethyl ester (gammay-GCE) (a membrane-permeating GSH precursor) was given to rats from gestation day 4 via the dam to postnatal day 14. Se deficiency induced a 62% incidence of electrocardiographic abnormalities such as sinus arrhythmias or extrasystole, a 63% reduction in dP/dt in the left ventricle, and an increase in thiobarbituric acid reacting substances (TBARS), but no ultrastructural cardiac lesions were observed. Administration of gamma-GCE increased the intracellular GSH concentration ([GSH]i) of both neonatal rat hearts and cultured fetal rat cardiac myocytes. gamma-GCE-like sodium selenite prevented the cardiac dysfunction and the TBARS increment. gamma-GCE also prevented H2O2 toxicity in the cultured myocytes. The Vmax, but not the Km, for GSH of Se-dependent GSH peroxidase (Se-Gpx) activity in Se-deficient rat heart homogenates was one-third that of normal rat heart homogenates. Although gamma-GCE did not affect the Se-Gpx Vmax and Km for GSH, it did induce a substantial and significant increase in [GSH]i, which was postulated to increase the velocity of H2O2 decomposition by Se-Gpx activity 1.6-fold. These data suggest that the increase in [GSH]i may have played a role in preventing the TBARS increase and cardiac dysfunction in Se-deficient rats.

Isolation, characterization, and chromosomal mapping of a novel cDNA clone encoding human selenium binding protein

We have isolated the full-length human 56 kDa selenium binding protein (hSP56) cDNA clone, which is the human homolog of mouse 56 kDa selenium binding protein. The cDNA is 1,668 bp long and has an open reading frame encoding 472 amino acids. The calculated molecular weight is 52.25 kDa and the estimated isoelectric point is 6.13. Using Northern blot hybridization, we found that this 56 kDa selenium binding protein is expressed in mouse heart with an intermediate level between those found in liver/lung/kidney and intestine. We have also successfully expressed hSP56 in Escherichia coli using the expression vector-pAED4. The hSP56 gene is located at human chromosome 1q21-22).