Superoxide and lipid free-radical generation in cultured endothelial cells treated with menadione or nitrazepam were measured using electron paramagnetic resonance spectroscopy. Superoxide was detected both intracellularly and extracellularly. Extracellular generation of superoxide and hydrogen peroxide was also measured, either by spectrophotometric measurement of succinoylated cytochrome c re...

Cultured macrophages exhibit spreading in response to external stimuli. It is relevant to in vivo morphologic changes of macrophages during extravasation, migration, and differentiation. The present study was performed to elucidate molecular mechanisms that regulate spreading of macrophages. Redox is a crucial factor that modulates a wide range of cell function. We found that macrophages underg...

Most of the research concerning the biological role of vitamin Kr (2methyl-3-phytyl-l , 4naphthoquinone) has been concerned with its function in blood clotting (1) ; however, substances which possess vitamin K activity are found in organisms such as bacteria and higher plants (1,2) which have no blood-clotting system. The role of the vitamin in these organisms has not been established but may b...

Mechanisms of estrogen-induced tumorigenesis in the target organ are not well understood. It has been suggested that oxidative stress resulting from metabolic activation of carcinogenic estrogens plays a critical role in estrogen-induced carcinogenesis. We tested this hypothesis by using an estrogen-induced hamster renal tumor model, a well established animal model of hormonal carcinogenesis. H...

Gene expression of three antioxidant enzymes, Mn superoxide dismutase (MnSOD), Cu,Zn superoxide dismutase (Cu,ZnSOD), and glutathione reductase (GR) was investigated in stationary phase Saccharomyces cerevisiae during menadione-induced oxidative stress. Both GR and Cu,ZnSOD mRNA steady state levels increased, reaching a plateau at about 90 min exposure to menadione. GR mRNA induction was higher...

Bacterial wilt and grey mould in tomato plants are economically destructive bacterial and fungal diseases caused by Ralstonia solanacearum and Botrytis cinerea, respectively. Various approaches including chemical and biological controls have been attempted to arrest the tomato diseases so far. In this study, in vitro growths of bacterial R. solanacearum and fungal B. cinerea were evaluated usin...

8th Day superoxide dismutase (SOD)-Like Supreme (SOD-Like Supreme, a free radical scavenging health product) is an antioxidant-enriched fermentation preparation with free radical scavenging properties. In the present study, the cellular/tissue protective actions of SOD-Like Supreme against menadione toxicity in cultured H9c2 cardiomyocytes and in AML12 hepatocytes as well as oxidant-induced inj...

Following previous work, we investigated in more detail the relationship between apoptosis and delayed luminescence (DL) in human leukemia Jurkat T cells under a wide variety of treatments. We used menadione and hydrogen peroxide to induce oxidative stress and two flavonoids, quercetin, and epigallocatechin gallate, applied alone or in combination with menadione or H(2)O(2). 62 MeV proton beams...

By CHARLES W. MUSHErF, KANE L. KELLEY AND RALPH HLRSCHMANN H YPOPROTHROMBINEMIA, resulting from simple vitamin K lack such as occurs in dietary deficiency in the chick or in absorptive difficulties in man, responds almost equally well to treatment with vitamin K1 (2-methyl3-phytyl-1,4-naphthoquinone) or Menadione (2-methyl-1,4-naphthoquinone) and water-soluble Menadione analogues.13 That this m...

Wosilait and Nason (1) demonstrated that quinones could serve as electron acceptors for the enzymatic oxidation of reduced pyridine nucleotides, and their survey of plant, animal, and microorganism extracts (2) revealed the general occurrence of reduced pyridine nucleotide-quinone reductase activity. This finding and Dam’s (3) earlier report, which indicated that vitamin K was a common constitu...