4-hydroxy-2-nonenal and thiobarbituric-acid

To clarify whether there is oxidative stress in Kashin-Beck disease (KBD) and if cartilage damage from reactive oxygen species (ROS) and oxidative stress mediate the chondral necrosis in articular cartilage of KBD.. We recruited 64 KBD patients, 46 healthy children from severely affected KBD regions, 81 healthy children from a non-severely affected KBD endemic regions, and 91 healthy control children from a non-KBD region. Ten patients with KBD from the non-severely affected KBD regions were included in the experiment. The 2,3-DAN fluorescence technique was used to test selenium in the hair and blood. The biochemical techniques used to test the indicators of oxidative stress included thiobarbituric acid reactive substances (TBARS) levels, and antioxidant enzyme activities in serum samples. Histochemical staining was used to detect proteoglycans in cartilage sections. The 4-hydroxy-2-nonenal (4-HNE) and 8-hydroxydeoxyguanisine (8-OHdG) were localized by immunohistochemistry.. The levels of TBARS in serum were significantly increased in KBD children. The levels of antioxidants in serum were significantly higher in both KBD and normal children from KBD regions than in the normal children from non-KBD regions. The percentage of chondrocytes staining for 4-HNE and 8-OHdG in KBD patients was significantly higher than in controls. Staining for 4-HNE and 8-OHdG in KBD patients was prominent in all zones of articular cartilage, especially in the necrotic chondrocytes of the deep zone.. KBD is an oxidative stress-related disease, and the oxidative stress in cartilage contributes to the pathology of cartilage damage in KBD.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Antioxidants; Cartilage, Articular; Case-Control Studies; Child; Child, Preschool; Chondrocytes; Deoxyguanosine; Female; Hair; Humans; Kashin-Beck Disease; Lipid Peroxidation; Male; Oxidative Stress; Proteoglycans; Selenium; Thiobarbiturates

Several functional differences have been reported among the three human e2, e3, and e4 alleles of apolipoprotein E (apoE). One functional difference lies in the antioxidant potential of these alleles; e4 has the poorest potential. Interestingly, e4 also correlates with increased oxidative damage in the Alzheimer's disease (AD) brain, which may explain why the inheritance of the e4 allele is a risk factor for the onset of AD. Beta-amyloid (Abeta) is also intimately involved in AD and promotes oxidative damage in vitro; therefore, we have examined the role of the different apoE alleles in modulating Abeta(1-42)-induced oxidation to synaptosomes. Measurement of specific markers of oxidation in synaptosomes isolated from mice that express one of the human apoE alleles indicates that Abeta-induced increases of these markers can be modulated by apoE in an allele-dependent manner (e2>e3>e4). Increases in reactive oxygen species formation and protein and lipid oxidation were always greatest in e4 synaptosomes as compared to e2 and e3 synaptosomes. Our data support the role of apoE as a modulator of Abeta toxicity and, consistent with the antioxidant potentials of the three alleles, suggest that the e4 allele may not be as effective in this role as the e2 or e3 alleles of apoE. These results are discussed with reference to mechanistic implications for neurodegeneration in the AD brain.

Topics: Aldehydes; Alleles; Alzheimer Disease; Amyloid beta-Peptides; Animals; Apolipoproteins E; Brain; Cyclic N-Oxides; Lipid Peroxidation; Mice; Mice, Transgenic; Nerve Tissue Proteins; Neurons; Oxidative Stress; Peptide Fragments; Reactive Oxygen Species; Synaptosomes; Thiobarbiturates

The study investigated the relationship between lipid peroxidation and enzyme inactivation in rat hepatic microsomes and whether prior inactivation of aldehyde dehydrogenase (ALDH) exacerbated inactivation of other enzymes. In microsomes incubated with 2.5 microM iron as ferric sulfate and 50 microM ascorbate, ALDH, glucose-6-phosphatase (G6Pase) and cytochrome P450 (Cyt-P450) levels decreased rapidly and concurrently with increased levels of thiobarbituric acid-reactive substances. Microsomal glutathione S-transferase and nicotinamide adenine dinucleotide phosphate-cytochrome c reductase were little affected during 1 hr of incubation. Addition of reduced glutathione partially protected and N,N'-diphenyl-p-phenylenediamine and butylated hydroxytoluene completely protected microsomes against inactivation of ALDH, G6Pase and Cyt-P450, as well as lipid peroxidation induced by iron and ascorbate. ALDH was more susceptible than G6Pase to inactivation by iron and ascorbate, and was thus an excellent marker for oxidative stress. Inhibition of ALDH by cyanamide injection of rats exacerbated the inactivation of G6Pase in microsomes incubated with 0.1 mM, but not 25 microM 4-hydroxynonenal (4-HN). 4-HN did not stimulate lipid peroxidation. Thus, 4-HN may play a minor role in microsomal enzyme inactivation. In contrast, lipid peroxyl radicals play an important role in microsomal enzyme inactivation, as evidenced by the prevention of both lipid peroxidation and enzyme inactivation by chain-breaking antioxidants.

Topics: Aldehyde Dehydrogenase; Aldehydes; Animals; Antioxidants; Butylated Hydroxytoluene; Cyanamide; Enzymes; Glutathione; Intracellular Membranes; Lipid Peroxidation; Microsomes, Liver; Phenylenediamines; Rats; Thiobarbiturates

In hepatic iron overload, iron-catalyzed lipid peroxidation has been implicated in the mechanisms of hepatocellular injury. Lipid peroxidation may produce reactive aldehydes such as malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), which may form aldehyde-protein adducts. We investigated whether lipid peroxidation occurred in rats fed a diet containing 3% carbonyl iron for 5-13 wk, and if this resulted in the formation of MDA- and 4-HNE- protein adducts. Chronic iron feeding resulted in hepatic iron overload (greater than 10-fold) and concomitantly induced a 2-fold increase in hepatic lipid peroxidation. Using an antiserum specific for MDA-lysine protein adducts, we demonstrated by immunohistochemistry the presence of aldehyde-protein adducts in the cytosol of periportal hepatocytes, which co-localized with iron. In addition, MDA- and 4-HNE-lysine adducts were found in plasma proteins of animals with iron overload. Only MDA adducts were detected in albumin, while other plasma proteins including a approximately 120-kD protein had both MDA and 4-HNE adducts. In this animal model of hepatic iron overload, injury occurs primarily in periportal hepatocytes, where MDA-lysine protein adducts and excess iron co-localized.

Topics: Aldehydes; Animals; Body Weight; Electrophoresis, Gel, Two-Dimensional; Fluorescence; Iron; Lipid Peroxides; Liver; Lysine; Male; Malondialdehyde; Molecular Weight; Proteins; Rats; Rats, Inbred Strains; Thiobarbiturates

Topics: Aldehydes; Chromatography, High Pressure Liquid; Colorimetry; Fatty Acids, Nonesterified; Gas Chromatography-Mass Spectrometry; Indicators and Reagents; Lipid Peroxides; Malondialdehyde; Oxidation-Reduction; Thiobarbiturates

Topics: Aldehydes; Animals; Disease Models, Animal; Dogs; Free Radicals; Hydrogen Peroxide; Hypoxanthine; Hypoxanthines; Lactates; Lactic Acid; Lipid Peroxidation; Malondialdehyde; Shock, Traumatic; Spectrometry, Fluorescence; Superoxides; Thiobarbiturates