To investigate whether, and by what mechanisms, luminal (dietary) cholesterol regulates cholesterol synthesis in human intestinal cells, HMG-CoA reductase activity, gene expression, synthesis, and degradation were investigated in CaCo-2 cells exposed to taurocholate micelles containing cholesterol. In cells incubated with cholesterol solubilized in 5 mM taurocholate and 30 microM monoolein, HMG...

The two compounds compactin and ML-236B are identical fungal metabolites isolated from strains of Penicilliunz brevicompactum and Penicillium citrinum, respectively. ML-236B has been shown to be a potent competitive inhibitor of rat liver microsomal 3-hydroxy-3-methylgluiaryl coenzyme A reductase (HMG-CoA reductase), the rate-controlling enzyme in cholesterol biosynthesis (Endo, A., Kuroda, M.,...

Introduction: Environmental pollution with heavy metals such as mercury is a major health problem. Growing studies on the field have shown the deleterious effects of mercury on human and nonhuman nervous system, especially in infants, however the effects of prenatal exposure to mercuricchloride on cortical development are not yet well understood. The aim of this study was to investigate the eff...

Thioredoxin reductase and thioredoxin constitute the cellular thioredoxin system, which provides reducing equivalents to numerous intracellular target disulfides. Mammalian thioredoxin reductase contains the rare amino acid selenocysteine. Known as the "21st" amino acid, selenocysteine is inserted into proteins by recoding UGA stop codons. Some model eukaryotic organisms lack the ability to ins...

One of the important abiotic stresses that negatively affect cereals such as wheat is heavy metals. Soil pollution with heavy metals has become one of the major environmental concerns resulting from the industrial development and use of fertilizers containing heavy metals. One way to counteract the negative effects of heavy metals in plants which produce reactive oxygen species is the activatio...

PURPOSE Increased flux of glucose via the polyol pathway, oxidative stress and ischaemia lead to the upregulation of the aldose reductase (AR), the key enzyme of the polyol pathway. This adversely affects the organism and can in part be reduced by inhibition of the enzyme. METHODS In this study, we examined the effect of the HMG-CoA-reductase inhibitor atorvastatin on the expression of aldose...

Most phytoremediation studies utilize merA or merB genes to modify plants via the nuclear or chloroplast genome, expressing organomercurial lyase and/or mercuric ion reductase in the cytoplasm, endoplasmic reticulum or within plastids. Several plant species including Arabidopsis, tobacco, poplar, rice, Eastern cottonwood, peanut, salt marsh grass and Chlorella have been transformed with these g...

The partial purification of the enzyme, aromatic aldehydeketone reductase (aromatic A-K reductase), from rabbit kidney cortex is described. Aromatic A-K reductase utilizes TPNH but not DPNH as a cosubstrate. Substituted benzaldehydes and acetophenones are readily reduced to carbinols. Aromatic A-K reductase does not, however, catalyze the reverse reaction, the dehydrogenation of carbinols under...