生物化学技术

4-Hydroxynonenal (4-hydroxy-2,3-trans-nonenal; 4-HNE) is the best known and thoroughly studied aldehydic product originating in biological samples during the process of lipid peroxidation (Fig. 1) (1). The latter is an autocatalytic, self-propagating sequence of free radical r ...

Neurons in widely disparate regions of the central nervous system (CNS), regions not intimately associated with reproductive behaviors, express the estrogen gene. Recent in situ hybridization (ISH) studies have documented the widespread distribution of estrogen receptor mRNA ...

The pleiotropic cytokine, tumor necrosis factor-α (TNF-α), has been shown to affect not only pathological and inflammatory conditions, but also plays a seminal role in the maintenance of physiological homeostasis. Due to these diverse activities, TNF-α is widely studied using various a ...

Advanced glycation endproducts (AGEs) are stable end-stage adducts formed by the nonenzymatic reaction of saccharide derivatives with proteins, nucleotides, and phospholipids. They are formed in physiological systems by glycation reactions of glucose and physiological α- ...

Lipid peroxidation alters membrane structure-function relationships by disrupting chemical bonds associated with phospholipid acyl chains (1). Fluorescence polarization techniques have been used previously to demonstrate changes in membrane fluidity, one of the cons ...

Fluorescence generated in living cells has been referred to as an age-related lipofuscin-like substances and also an index of aging (1,2). Cells and tissues contain three kinds of fluorescence: yellow, green, and blue. Among them, yellow fluorescence that fluoresced at around 620 nm is regard ...

Diabetes mellitus is associated with increased reactive oxygen species (ROS) generation by mononuclear cells (MNC) and an increased oxidative load, which causes oxidative damage to proteins, lipids and DNA (1–3). Recently, we have demonstrated that glucose challenge causes an incre ...

The transcription factor NF-κB was first identified as a regulator of the expression of the kappa light-chain gene in murine B lymphocytes (1). It has a central role in the immunological processes and regulates a wide range of genes in a rapid fashion (2). NF-κB interacts with its inhibitor protein IκB a ...

Stimulation of neutrophils induces oxidative burst. The generations of oxygen radicals play a central role in host defense against bacteria. Once neutrophils are stimulated by inflammatory or bacterial stimuli, they produce superoxide anion in order to kill phagocytosed microo ...

Electrophoretic mobility shift assay (EMSA) provides a fast and sensitive method for detecting sequence-specific DNA-binding proteins (see Fig. 1). Using an end-labeled DNA oligonucleotide as probe, proteins that specifically bind to these DNA sequence retard the mobility of the fr ...

Stress response is nearly universal. Living organisms respond to the changes in their chemical, physical, and biological environments by synthesizing a group of proteins called stress or heat-shock proteins (1). The preferential synthesis of these proteins appears to be involved in in ...

One major source of reactive oxygen species (ROS) is the Fenton reaction: Fe2+ + H2O2 Fe3 + HO- + HO� Mass action implies that ROS generated by the Fenton reaction depend on the intracellular concentration of ferrous ions () although other metabolic fluxes make it difficult to capture this concentrat ...

Gene expression plays an important role in many biological processes. During development, for example, early developmental genes are turned on first to guide embryonic pattern formation (1–3). A stress, either a physiological/ pathophysiological or an environmental one, can also re ...

The modulation of gene expression by cellular stress is a universal phenomena that has been described in organisms ranging from bacteria to animals to plants, and in response to a wide range of stress agents including heat shock, glucose deprivation, oxidants, radiation, and heavy metals (1). F ...

Oxygen radicals are chemical species that have an unpaired electron in their outer orbits. The unpaired electron gives the radical instability and it reacts easily with inorganic or organic chemicals. The three most important species are superoxide, hydrogen peroxide, and hydroxyl io ...

Oxidative stress evokes various cellular responses including alteration of gene expression to preserve cellular homeostasis (1,2). Thioredoxin (TRX) is a small ubiquitous protein with protein thiol-reducing activity and has been shown to function as a cellular antioxidant buf ...

Phospholipid hydroperoxide glutathione peroxidase (PHGPX or GPX4, E.C. 1.11.1.12) is one of the four identified selenium-dependent glutathione peroxidases (GPX) in mammals (1). Both of the pig (2.8 kb) and the mouse (4.0 kb) GPX4 genes contain seven exons and six introns, with putative regulat ...

Among lipid peroxides and related free radicals in the process of lipid peroxidation, the first stable products, lipid hydroperoxides, are unique from the viewpoint of pathogenicity. Because of their stability, these hydroperoxides can migrate throughout the body via the bloodstr ...

It is well known that the superoxide anion radical (O-2) is produced in the body as a result of biochemical activities of many cells, such as neutrophils, macrophages, and Kupffer cells (1). Production of O-2 is detectable by various methods, including cytochrome-c oxidation (1), nitroblue tetra ...

Cellular redox environment is a critical determinant of stress-induced cellular responses and the progression of disease (1). Under normal (nonstress) conditions, the cell maintains a strong reducing environment that favors reductive over highly compartmentalized oxidat ...