Dehydroepiandrosterone protects hippocampal neurons against neurotoxin-induced cell death: mechanism of action.

Dehydroepiandrosterone (DHEA), an adrenal cortex hormone secreted in large quantities in humans, protects cells of the clonal mouse hippocampal cell line HT-22 against the excitatory amino acid glutamate (5 mM), and amyloid beta-protein (2 microM) toxicity in a dose-dependent manner with optimum protection obtained at 5 microM concentration of DHEA. The protective effects of DHEA appear to be specific in that other related steroids and metabolites of DHEA, such as 5-androstene-3beta,17beta-diol, etiocholan-3alpha-ol-17-one, etiocholan-3beta-ol-17-one, testosterone, and 5alpha-androstane-3, 17-dione, offered no protection even at 50 microM concentrations. In addition, using immunocytochemical techniques, we observed that 20 hr of treatment with 5 mM glutamate remarkably increased glucocorticoid receptor (GR) nuclear localization in neuronal cells.

Antibacterial and immunostimulating casein-derived substances from milk: casecidin, isracidin peptides.

Apart from immunoglobulin A and G antibodies and plasma cells, milk also contains antibiotic/host protective peptides that are of value not only for maintenance of its nutritional integrity but also for protection of the newborn and, possibly, protection of the lactating mother. Among the first such peptides identified with casecidin; following chymosin digestion of casein at pH 6 or 7, casecidin inhibited in vitro staphylococci, sarcina, Bacillus subtilis, Diplococcus pneumoniae and Streptococcus pyogenes. Inhibition occurred at high concentrations, in vitro, compared with commercial antibiotics, and thus interest in casecidin languished.

Review of the biology of Quercetin and related bioflavonoids.

The French paradox is a dietary anomaly which has focused attention on the Mediterranean diet. Epidemiological studies revealed that this diet, replete in flavonoid-rich foods (Allium and Brassica vegetables, and red wine), correlated with the increased longevity and decreased incidence of cardiovascular disease seen in these populations. The most frequently studied flavonoid, quercetin, has been shown to have biological properties consistent with its sparing effect on the cardiovascular system.