AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological s...AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological saline(saline group) or H2-dissolved saline(H2 group) was instilled continuously on the cornea for 5 min before and after alkali exposure. Inflammatory cells, neovascularization, and cytoplasmic SOD1 levels were evaluated immunohistochemically in enucleated eyes from both groups. Three-dimensional ultrastructural tissue changes in the eyes were analyzed using low-vacuum scanning electron microscopy.RESULTS: The numbers of both inflammatory and vascular endothelial cells were significantly reduced in the corneas of the H2 group(P<0.01). Furthermore, H2 treatment increased both cytoplasmic SOD1 levels(P<0.01) and activity in corneal epithelial cells(P<0.01). Notably, the SOD1 activity level in the H2 group was approximately 2.5-fold greater than that in the saline group.CONCLUSION: H2 treatment suppresses inflammation and neovascularization in the injured cornea and indirectly suppresses oxidative insult to the cornea by upregulating the SOD1 enzyme protein level and activity.展开更多
The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive ex...The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive expression was detected by constructing the expression vector transferred Cu/Zn-SOD gene into wild-type S. cerevisiae. Transcription and expression of the Cu/Zn-SOD gene in S. cerevisiawere were confirmed by northern blot and SDS-PAGE, respectively, and activity of the Cu/Zn-SOD from crude extracts was enzymatically detected based on the effect of nitroblue tetrazolium （NBT） after running a native polyacrylamide gel. The GSH synthesis was also tested by DTNB （5, 5＇-Dithiobis （2-nitrobenzoic acid）） method. Results showed that GSH synthesis was evidently suppressed by the expression of Cu/Zn-SOD gene in both control and heat shock strains. It implied that the expression of the Cu/Zn-SOD gene in S. cerevisiae has more potential facility in response to oxidative exposure than that of endogenous GSH, although Cu/Zn-SOD and GSH were both contributed to the function of oxygen radical oxidoreduction.展开更多
Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels o...Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels of Cu/Zn-SOD are higher in the serum of hemodialysis patients than in serum of healthy volunteers. The increase of serum Cu/Zn-SOD levels is related to the decrease of kidney function with aging and arteriosclerosis in hemodialysis patients. Moreover, infection, vascular puncture, and hemostasis may be related to the increase in serum Cu/Zn-SOD levels. As it is associated with numerous factors in hemodialysis patients, Cu/Zn-SOD may serve as a complex marker for arteriosclerosis, vascular, and inflammatory conditions. It is important to investigate various agents that decrease serum Cu/Zn-SOD levels to improve the life-span of hemodialysis patients.展开更多
Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of...Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.展开更多
When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic...When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.展开更多
文摘AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological saline(saline group) or H2-dissolved saline(H2 group) was instilled continuously on the cornea for 5 min before and after alkali exposure. Inflammatory cells, neovascularization, and cytoplasmic SOD1 levels were evaluated immunohistochemically in enucleated eyes from both groups. Three-dimensional ultrastructural tissue changes in the eyes were analyzed using low-vacuum scanning electron microscopy.RESULTS: The numbers of both inflammatory and vascular endothelial cells were significantly reduced in the corneas of the H2 group(P<0.01). Furthermore, H2 treatment increased both cytoplasmic SOD1 levels(P<0.01) and activity in corneal epithelial cells(P<0.01). Notably, the SOD1 activity level in the H2 group was approximately 2.5-fold greater than that in the saline group.CONCLUSION: H2 treatment suppresses inflammation and neovascularization in the injured cornea and indirectly suppresses oxidative insult to the cornea by upregulating the SOD1 enzyme protein level and activity.
基金overseas returned scholars’ starting working grants to AN Zhi-gang (Northeast Forestry University)
文摘The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive expression was detected by constructing the expression vector transferred Cu/Zn-SOD gene into wild-type S. cerevisiae. Transcription and expression of the Cu/Zn-SOD gene in S. cerevisiawere were confirmed by northern blot and SDS-PAGE, respectively, and activity of the Cu/Zn-SOD from crude extracts was enzymatically detected based on the effect of nitroblue tetrazolium （NBT） after running a native polyacrylamide gel. The GSH synthesis was also tested by DTNB （5, 5＇-Dithiobis （2-nitrobenzoic acid）） method. Results showed that GSH synthesis was evidently suppressed by the expression of Cu/Zn-SOD gene in both control and heat shock strains. It implied that the expression of the Cu/Zn-SOD gene in S. cerevisiae has more potential facility in response to oxidative exposure than that of endogenous GSH, although Cu/Zn-SOD and GSH were both contributed to the function of oxygen radical oxidoreduction.
文摘Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels of Cu/Zn-SOD are higher in the serum of hemodialysis patients than in serum of healthy volunteers. The increase of serum Cu/Zn-SOD levels is related to the decrease of kidney function with aging and arteriosclerosis in hemodialysis patients. Moreover, infection, vascular puncture, and hemostasis may be related to the increase in serum Cu/Zn-SOD levels. As it is associated with numerous factors in hemodialysis patients, Cu/Zn-SOD may serve as a complex marker for arteriosclerosis, vascular, and inflammatory conditions. It is important to investigate various agents that decrease serum Cu/Zn-SOD levels to improve the life-span of hemodialysis patients.
基金Supported by University Grants Commission,New Delhi(F.403(M/S)/2009(SA-Ⅲ/MANF)
文摘Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.
文摘When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.
