Journal of free radicals in biology & medicine最新文献

{"title":"Announcements and calendar","authors":"","doi":"10.1016/0748-5514(85)90126-6","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90126-6","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 3","pages":"Pages 241-242"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90126-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136933011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Charge transfer and oxy radicals in antimalarial action. Quinones, dapsone metabolites, metal complexes, imunium ions, and peroxides","authors":"James R. Ames ,&nbsp;Michael D. Ryan ,&nbsp;Daniel L. Klyman ,&nbsp;Peter Kovacic","doi":"10.1016/0748-5514(85)90147-3","DOIUrl":"10.1016/0748-5514(85)90147-3","url":null,"abstract":"<div><p>A mechanism of action is proposed that encompasses almost all of the main categories of antimalarial agents: quinones and precursors, dapsone metabolites, metal complexes of thisemicarbazones and biguanides, imunium-type ions from acridines and quinolines, and peroxides. The toxic effect of the drugs is believed to result from the generation of reactive oxygen oxygen radicals that usually arise via charge transfer. Electrochemical studies (reduction potential and reversibility) were performed on a number of these agents. Reduction potentials range from −0.23 to −1.52 V. It is likely that the in vivo values are aprreciably more positive in certain cases.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 5","pages":"Pages 353-361"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90147-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14955084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enzymatic determination of membrane lipid peroxidation","authors":"Matilde Maiorino,&nbsp;Antonella Roveri,&nbsp;Fulvio Ursini,&nbsp;Carlo Gregolin","doi":"10.1016/0748-5514(85)90119-9","DOIUrl":"10.1016/0748-5514(85)90119-9","url":null,"abstract":"<div><p>The recently purified “phospholipid hydroperoxide glutathione peroxidase” has been used to measure the membrane hydroperoxides formed during lipid peroxidation that are not substrates for the “classical” glutathione peroxidase. A spectrophotometric test in the presence of glutathione, glutathione reductase and NADPH has been used. The peroxidized membranes were added directly to the reaction mixture and the reaction was started by the addition of the enzyme. Triton X-100 exerted a stimulatory effect. Phospholipid hydroperoxide glutathione peroxidase allows a rapid, sensitive, accurate and specific determination of membrane hydroperoxides, the most quantitative index of lipid peroxidation. Glutathione peroxidase can be used in the same test to measure other hydroperoxides such as the cumene hydroperoxide used to induce the peroxidation.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 3","pages":"Pages 203-207"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90119-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14952581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Announcements and calendar","authors":"","doi":"10.1016/0748-5514(85)90164-3","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90164-3","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 5","pages":"Pages 475-476"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90164-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134686133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Announcements and calendar","authors":"","doi":"10.1016/0748-5514(85)90033-9","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90033-9","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 1","pages":"Page 83"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90033-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136938094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Superoxide radical from xanthine oxidase acting upon lumazine","authors":"Tetsuo Nagano,&nbsp;Irwin Fridovich","doi":"10.1016/0748-5514(85)90027-3","DOIUrl":"10.1016/0748-5514(85)90027-3","url":null,"abstract":"<div><p>The univalent and divalent reductions of dioxygen were measured using lumazine as a low turnover substrate and both xanthine and acetaldehyde as high turnover substrates. These measurements were made in solutions equilibrated with air and with 100% O₂. The univalent route of dioxygen reduction predominated with the low turnover substrate and was increased by raising pO₂ and by lowering substrate concentration. These results support the view that electron egress from heavily reduced xanthine oxidase occurs by divalent transfers, while that from the partially reduced enzyme is by univalent transfers. Xanthine oxidase, acting as lumazine, is a convenient source of O₂^⨪.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 1","pages":"Pages 39-42"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90027-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14146650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consecutive action of phospholipase A2 and glutathione peroxidase is required for reduction of phospholipid hydroperoxides and provides a convenient method to determine peroxide values in membranes","authors":"Frederik J.G.M. van Kuijk ,&nbsp;Garry J. Handelman,&nbsp;Edward A. Dratz","doi":"10.1016/0748-5514(85)90156-4","DOIUrl":"10.1016/0748-5514(85)90156-4","url":null,"abstract":"<div><p>The purpose of this study was to investigate the ability of selenium-dependent glutathione peroxidase to reduce phospholipid hydroperoxides in membrane bilayers and to develop a method to measure the peroxide content of phospholipids. Phospholipid hydroperoxides were synthesized by photooxidation of 1-palmitoyl 2-linoleoyl phosphatidylcholine and characterized by gas chromatography-mass spectrometry. Phospholipid hydroperoxides in phosphatidylcholine bilayers showed no detectable reactivity with Se-dependent glutathione peroxidase (the reaction is at least 65,000 times slower than with an available hydroperoxide). However, after the phospholipid hydroperoxides were preincubated with phospholipase A2, the free fatty acid hydroperoxides became available as a substrate for Se-dependent glutathione peroxidase. The enzyme assay can be used for convenient determination of peroxide values in phospholipids at the 1 nmole level and free fatty acid hydroperoxides can be distinguised from phospholipid hydroperoxides by omitting phospholipase A2. The accuracy of the enzymatic method was confirmed using an improved colorimetric chemical assay to measure peroxide values of phospholipid hydroperoxides to the same sensitivity. The chemical assay was not linear in the presence of high levels of lipid, but at low levels of lipid the peroxide values of phospholipid hydroperoxides measured by both methods agreed to within 1%. Since high levels of lipid inhibited the chemical assay, the enzyme assay is more accurate for determination of peroxides in membranes and tissues. The possible role of phospholipase deficiencies as a causal factor in degenerative diseases thought to be due to lipid peroxidation, such as Neuronal Ceroid Lipofuscinosis (Battens disease), is discussed.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 5","pages":"Pages 421-427"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90156-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14955087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antioxidant enzyme content of pulmonary artery endothelial cells: Effects of subculture","authors":"David H.L. Hart,&nbsp;Jane E. Hobson,&nbsp;David C. Walker,&nbsp;Anne P. Autor","doi":"10.1016/0748-5514(85)90157-6","DOIUrl":"10.1016/0748-5514(85)90157-6","url":null,"abstract":"<div><p>The activities of glutathione peroxide, superoxide dismutase and catalase, enzymes which play a critical role in protection of the vascular endothelium from oxygen free-radical injury, were determined in large vessel endothelial cells obtained under three different growth conditions: (1) from freshly isolated from bovine pulmonary arteries, (2) in the first (primary) subculture and (3) after six serial subcultures (6.5 population doublings). The endothelium was obtained by mechanically scraping the vascular lumen. Endothelial cell monolayers were detached mechanically from the substratum prior to passage. No proteolytic enzymes were used in either procedure. The activities of catalase, superoxide dismutase and glutathione peroxidase determined in freshly isolated endothelial cells were, respectively, 39.9 ± 10.3, 2.2 ± 0.8 and 3.0 ± 0.5 × 10⁻² units per mg protein. After primacy culture there was no change in superoxide dismutase activity, but a significant decrease in glutathione peroxidase activity to 1.4 ± 0.4 × 10⁻² was observed, and catalase activity dropped significantly to 18.6 ± 5.0 units per mg protein. After 6.5 population doublings, the activity of all three enzymes returned to values similar to those of the freshly isolated cells. A fourfold increase in the protein to DNA ratio occurred in cells in primary culture and was maintained in sixth-passage cells. This increase in endothelial cell size upon culture was reflected in the electron microscopic evidence of cellular hypertrophy. Measurement of the rate of transport of 5-hydroxytryptamine by endothelial cell monolayers revealed a substantial loss upon multiple passage. Transport in the sixth-passage cells was decreased to one-half the rate of primary cells. Comparison of the ultrastructural characteristics of cells from the three groups showed more endomembrane structure and higher numbers of mitochondria in the passaged cells, suggesting that passaged cells were more metabolically and synthetically active than in situ cells. In contrast, in situ cells showed more elaborate cell junction complexes than the passaged cells. The observed differences in antioxidant enzyme content, function and morphology between endothelial cells in situ and in culture underscore the need for careful characterization of cultured cells before their use as in vitro models for the vascular endothelium.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 5","pages":"Pages 429-435"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90157-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14955088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Doxorubicin-dependent lipid peroxidation at low partial pressures of O2","authors":"Christine C. Winterbourn ,&nbsp;John M.C. Gutteridge ,&nbsp;Barry Halliwell","doi":"10.1016/0748-5514(85)90028-5","DOIUrl":"10.1016/0748-5514(85)90028-5","url":null,"abstract":"<div><p>Doxorubicin semiquinone, produced by reduction of doxorubicin with xanthine oxidase or ferredoxin reductase, reacted with H₂O₂ to cause deoxyribose oxidation that was catalysed by sub-micromolar concentrations of complexed iron. Both the mechanism of deoxyribose oxidation and the yield of oxidation products depended on the chelator. With EDTA or diethylenetriamine penta-acetic acid (DTPA), the reactive species behaved like free ·OH. However, when ADP or no chelator was present, oxidation of deoxyribose was inhibited by mannitol but not benzoate or formate and was apparently not due to free ·OH. Doxorubicin semiquinone and H₂O₂ caused peroxidation of phospholipid lipsomes when ADP or no chelator was present, but not in the presence of EDTA or DTPA. Lipid peroxidation was iron dependent over a 0.1 to 1 μM range and was maximal with a pO₂ of approximately 1.5 mm Hg, when the inhibitory effect of O₂ on initiation is balanced by its stimulatory effects on propagation. The results imply that H₂O₂ and the doxorubicin semiquinone at low iron and O₂ concentrations are very effective at initiating lipid peroxidation.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 1","pages":"Pages 43-49"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90028-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15053191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interactions of lipid hydroperoxides with eicosanoid biosynthesis","authors":"William E.M. Lands","doi":"10.1016/0748-5514(85)90012-1","DOIUrl":"10.1016/0748-5514(85)90012-1","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 2","pages":"Pages 97-101"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90012-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"15053963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}