PURPOSE Reactive oxygen intermediates have been implicated in the aging process and degenerative diseases of the eye, including retinopathy of prematurity, cataractogenesis, and macular degeneration. The purpose of this study was to investigate the effect of phagocytosis of photoreceptor outer segments and the addition of exogenous H2O2 on catalase and metallothionein expression in human retina...

Lobsters were fed cadmium-rich oysters for 28 days, and the induction of cadmium metallothionein and its relation to concentrations of cadmium, copper, and zinc in the digestive gland and gills was determined. A portion of the tissues also was retained for determining the cytosolic distribution of these metals by gel filtration and ion-exchange chromatography. The digestive gland contained a ma...

This summary examines some of the known and hypothesized roles of metallothionein and related proteins in mediating the metal metabolism and toxicity from a chemical perspective. It attempts to examine in kinetic terms how such molecules may exert homeostatic control over the intracellular bioavailability of metal ions to essential enzymatic or other molecular systems. The concept of ongoing co...

many studies have proved that the dietary micronutrient has an inhibitory effect against experimentally induced rat hepatocarcinogenesis. the present work is an attempt to understand combined effect of selenium (se) and vitamin d3 (vit d3) on some potential protein expression markers of carcinogenesis, such as metallothionein (mt), p53 and antioxidant levels during diethyl nitrosamine (den) ind...

Escherichia coli strains were genetically engineered to express an Hg2+ transport system and metallothionein. Overexpression of a glutathione S-transferase fusion protein of Saccharomyces cerevisiae or pea metallothionein significantly increased the bioaccumulation of Hg2+ transported by MerT and MerP and protected the cells from the accumulated Hg2+. The recombinant strains have excellent prop...

Metallothioneins are a group of low-molecular-weight intracellular proteins present in high levels in fetal mammalian livers, bound to zinc and copper. They are also present in two major isoforms in low basal levels in various organs of adults in several species. Although a number of functions have been proposed for metallothioneins, their major biological roles may be in the storage of zinc an...

The objective of this work was to quantify metallothioneins (MT’s) in tissues of rats fed different concentrations of zinc, in order to observe the animal response to the metal in relation to different types of diets, and to assess the nutritional status relating to zinc in the diets. Thirty-two Wistar newly-weaned male rats were distributed into four experimental groups and housed in individua...

The objective was to discover whether the oxygen-regulated protein, metallothionein, is expressed in the hypoxic cells of squamous cell carcinomas. Twenty patients with squamous cell carcinoma of the uterine cervix or head and neck were infused with a solution of the hypoxia marker, pimonidazole hydrochloride, at a dose of 0.5 g/m2. The following day, biopsies were collected, formalin fixed, pa...

This study was undertaken to further establish the nature of the low molecular weight metal-binding proteins in rat testes. In all cases, control testes were compared to livers of zinc-treated rats, which are known to contain high concentrations of metallothionein. Gel filtration of testicular and hepatic cytosol revealed a major zinc- and/or cadmium-binding protein in the low molecular weight ...

Polymerization of metallothioneins is one of the usually encountered puzzles during the research process of metallothioneins' structure and function. Our work focuses on the cysteine independently occurred polymerization from metallothioneins monomers in different milieus, while it leaves out the aggregation caused by the oxidation of cysteine, because the latter circumstance is the result of p...