Showing 2 results for Carbonyl Group
Hadi Ansarihadipour, Maryamsadat Alhoseini, Soheila Rostami , Narges Farahani, Mahya Hashemi ,
Volume 15, Issue 2 (6-2012)
Abstract
Background: The aim of this study is to assess antioxidative and pro-oxidative efficacy of ascorbate on serum albumin during iron-induced oxidative stress. Materials and Methods: In this experimental study, albumin was placed in the oxidative system containing iron ions and different concentrations of ascorbate. To monitor albumin degradation, sodium dodecyl sulfate polyacrylamide gel electrophoresis was performed according to Laemmli procedure. Oxidative modification of albumin was demonstrated using a method for determination of carbonyl groups by 2,4-dinitrophenylhydrazine. Results: By applying the carbonyl assay, ascorbate showed a dual effect: initial pro-oxidative effect on albumin changed to an antioxidant one in a dose-dependent manner. Our findings showed prooxidant effects for ascorbate in low concentrations (0-100 µM) and antioxidant effects in higher concentrations (100-300 µM). Also, electrophoretic pattern of plasma proteins showed significant protein aggregations in the range of 35 to 45 kDa of MW and protein degradations in the range of 115 to 180 kDa. Conclusion: Ascorbate can produce reactive oxygen species and can also inhibit the production of these oxidants in the presence of iron ions as well. These findings may be directly applicable to oxidative states during the administration of ascorbate and may be important in preventing oxidative modifications of proteins in blood circulation and other biological fluids.
Hadi Ansarihadipour, Ali Bahadori Vatankhah, Saeed Ziraki, Mohamad Saiadi,
Volume 15, Issue 8 (1-2013)
Abstract
Background: The presence of oxidant agents yields higher levels of free radical reaction products in erythrocyte membrane proteins and serum proteins. The aim of this study is to investigate the oxidative modifications of recombinant human coagulation factor VIII (rHFVIII) by spectrophotometric analysis. Materials and Methods: In this experimental study, rHFVIII was incubated aerobically with vitamin C and ferro ions in metal catalyzed oxidation (MCO) system for 4 to 28 hr. Carbonyl assay was used as an index of protein oxidation. For this purpose, 2,4dinitrophenyl hydrazine (DNPH) was used. Reaction of this reagent with carbonyl groups produces dinitrophenylhydrazone derivatives that their concentration was estimated by spectrophotometry. Results: Carbonyl groups in rHFVIII changed in the presence of vitamin C and ferro ions. Dose-dependent effects of vitamin C showed a decrease in carbonyl groups of rHFVIII whileferro ions increased oxidation and carbonyl group formation in this protein. Conclusion: These findings indicate that changes in carbonyl groups in rHFVIII are related to the generation of reactive oxygen species. Also, antioxidant mechanisms are activated in a dose- and time-dependent manner.
