Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lawsone is an active naphthoquinone derivative isolated from henna (Lawsonia inermis L.), a widely used hair dye. Previous study on the toxicity of lawsone remains unclear since the involvement of oxidative stress and the kind of ROS (reactive oxygen species) involved have not been fully resolved yet. This present study reports the cytotoxic effects of lawsone and henna. We carried out CAT assay (a zone of inhibition test of bacterial growth and colony-forming efficiency test of transformant Escherichia coli strains that express mammalian catalase gene derived from normal catalase mice (Cs(a)) and catalase-deficient mutant mice (Cs(b))), Ames mutagenicity assay and H(2)O(2) generation assay. Lawsone generated H(2)O(2) slightly in phosphate buffer system and was not mutagenic in Ames assay using TA 98, TA 100 and TA 102, both in the absence and presence of metabolic activation. Lawsone exposure inhibited the growth of both Cs(a) and Cs(b) strains in a dose-dependent manner. Mean zone diameter for Cs(a) was 9.75+/-0.96 mm and 12.75+/-1.5 mm for Cs(b). Natural henna leaves did not show toxic effects, whereas two out of four samples of marketed henna products were shown toxicity effects. Catalase abolished zone of inhibition (ZOI) of marketed henna products, eliminated ZOI of lawsone in a dose-dependent manner and low concentration of exogenous MnSOD and Cu/ZnSOD eliminated the toxicity. Histidine and DTPA, the metal chelator; BHA and low concentration of capsaicin, the inducer of NADH-quinone reductase, effectively protected Cs(a) and Cs(b) against lawsone in this study. We suggest that lawsone cytotoxicity is probably mediated, at least in part, by the release of O(2)(-), H(2)O(2) and OH(-).
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PMID:Cytotoxicity of lawsone and cytoprotective activity of antioxidants in catalase mutant Escherichia coli. 1744 76

Manganese superoxide dismutase (Mn-SOD or SOD2) is a key antioxidant enzyme and was assigned several roles in tumor biology. Working on medulloblastoma cell line DAOY, we identified two spots as Mn-SODs. Because of the proposed pivotal role of this enzyme in oncobiology, we decided to completely sequence the proteins and to determine PTMs. Proteins extracted from DAOY cells were run on 2-DE, multienzyme digestions were carried out and peptides were analyzed by MALDI-TOF/TOF, Qq-TOF and the ion trap using both the CID and ETD principles. Both protein expression forms were completely sequenced and revealed identical protein sequences. Histidines His30 and His31 were oxidized in one protein, whereas tryptophan oxidation (Trp-186) was observed in both. Histidine oxidation was not only indicated by the mass shift of the peptide but also by specific spectra of 2-oxo-histidine and a previously described intermediate (His+14). Complete sequencing of the two Mn-SOD expression forms unambiguously characterizes this enzyme from a tumor cell line providing evidence that can be used for generation of antibodies and allowing conformational studies. The findings of different PTMs in the same gel represent Mn-SOD oxidative states, while oxidative modification of His30 and 31 may even reflect decreased Mn-SOD activity.
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PMID:Complete sequencing and oxidative modification of manganese superoxide dismutase in medulloblastoma cells. 1967 86