Studies were performed to determine the extent of nuclear DNA degradation induced by iron, iron-ascorbate, or iron-bleomycin under aerobic conditions in a model system using isolated rat liver nuclei. The effects of f...Studies were performed to determine the extent of nuclear DNA degradation induced by iron, iron-ascorbate, or iron-bleomycin under aerobic conditions in a model system using isolated rat liver nuclei. The effects of five antioxidants (catalase, superoxide dismutase, dimethyl sulfoxide, glutathione and diallyl sulfide) on this oxidative nuclear damage were also investigated. At the 0.05 level for statistical significance, iron induced concentration-dependent DNA degradation, and this effect was enhanced by ascorbate and bleomycin. The antioxidants catalase, dimethyl sulfoxide, and diallyl sulfide significantly reduced the iron-ascorbate-induced DNA damage, whereas superoxide dismutase and dimethyl sulfoxide significantly reduced iron-bleomycin-induced damage. Glutathione significantly increased the iron-bleomycin-induced DNA damage. These results suggest that the reactive oxygen species generated by iron, iron-ascorbate, and iron-bleomycin are responsible for the DNA strand breaks in isolated rat liver nuclei.展开更多
Background: Although a large number of studies have confirmed that the different levels of reactive oxygen species (ROS) in cytoplasm and nucleus have effects on cell growth, proliferation, differentiation and apoptos...Background: Although a large number of studies have confirmed that the different levels of reactive oxygen species (ROS) in cytoplasm and nucleus have effects on cell growth, proliferation, differentiation and apoptosis, the exact mechanism of ROS action is unclear. An important reason is that the production and degradation time of ROS in cells is very short, and therefore it’s difficult to understand the mechanism of action based on the traditional molecular action process through the ROS diffusion and target binding. Methods: The fresh liver tissue slices were prepared and the nuclei of hepatocytes were separated from Kunming mice according to the reported method. Liver tissue slices and hepatocyte nuclei were perfused with extracellular or intracellular fluids containing different concentrations of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), and real-time imaging monitoring of biophotonic emission was carried out using an ultra-weak biophoton imaging system. Results: The results showed that the continuous perfusion with different concentrations of H<sub>2</sub>O<sub>2</sub> (300, 400 and 500 μM, respectively) resulted in significant increase of biophotonic emissions, presenting a concentration-dependent effect in liver tissue slices and achieving the maximum effect at 400 μM, while the significant enhancement was found after 500 μM treatment on the hepatocyte nuclei. Conclusion: This study suggests that ROS generated in cells may achieve its physiological and pathological effects via biophotonic emissions, which provides a new quantum biological mechanism of ROS, while the detailed clarification requires further research.展开更多
Spindle fiber attachments (SFAs) were enriched in a fraction of nuclei isolated from mouselivers. The enrichment method combines sonication, treatment with 2 mol/L NaCl and highspeed centrifugation. SFA was enriched 2...Spindle fiber attachments (SFAs) were enriched in a fraction of nuclei isolated from mouselivers. The enrichment method combines sonication, treatment with 2 mol/L NaCl and highspeed centrifugation. SFA was enriched 27-fold on the average (n = 4) when measured byradioimmunoassay. The basic method offers opportunities for further increases of yield andfor the enrichment of SFA uf other vertebrates.展开更多
The liver proteome can serve as a reference to better understand both disease mechanisms and possible therapeutics,since the liver is an important organ in the body that performs a large number of tasks.Here we identi...The liver proteome can serve as a reference to better understand both disease mechanisms and possible therapeutics,since the liver is an important organ in the body that performs a large number of tasks.Here we identify the organelle proteome of C57BL/6J mouse liver nuclei as a promising strategy to enrich low abundance proteins,in the sense that analysis of whole liver cells is rather complex for current techniques and may not be suitable for proteins with low abundance.Evaluation of nucleus integrity and purity was performed to demonstrate the effectiveness of the optimized isolation procedure.The extracted nuclear proteins were identified by 2-DE MS analyses,and a total of 748 proteins were identified.Bioinformatic analyses were performed to demonstrate the physicochemical properties,cellular locations and functions of the proteins.展开更多
文摘Studies were performed to determine the extent of nuclear DNA degradation induced by iron, iron-ascorbate, or iron-bleomycin under aerobic conditions in a model system using isolated rat liver nuclei. The effects of five antioxidants (catalase, superoxide dismutase, dimethyl sulfoxide, glutathione and diallyl sulfide) on this oxidative nuclear damage were also investigated. At the 0.05 level for statistical significance, iron induced concentration-dependent DNA degradation, and this effect was enhanced by ascorbate and bleomycin. The antioxidants catalase, dimethyl sulfoxide, and diallyl sulfide significantly reduced the iron-ascorbate-induced DNA damage, whereas superoxide dismutase and dimethyl sulfoxide significantly reduced iron-bleomycin-induced damage. Glutathione significantly increased the iron-bleomycin-induced DNA damage. These results suggest that the reactive oxygen species generated by iron, iron-ascorbate, and iron-bleomycin are responsible for the DNA strand breaks in isolated rat liver nuclei.
文摘Background: Although a large number of studies have confirmed that the different levels of reactive oxygen species (ROS) in cytoplasm and nucleus have effects on cell growth, proliferation, differentiation and apoptosis, the exact mechanism of ROS action is unclear. An important reason is that the production and degradation time of ROS in cells is very short, and therefore it’s difficult to understand the mechanism of action based on the traditional molecular action process through the ROS diffusion and target binding. Methods: The fresh liver tissue slices were prepared and the nuclei of hepatocytes were separated from Kunming mice according to the reported method. Liver tissue slices and hepatocyte nuclei were perfused with extracellular or intracellular fluids containing different concentrations of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), and real-time imaging monitoring of biophotonic emission was carried out using an ultra-weak biophoton imaging system. Results: The results showed that the continuous perfusion with different concentrations of H<sub>2</sub>O<sub>2</sub> (300, 400 and 500 μM, respectively) resulted in significant increase of biophotonic emissions, presenting a concentration-dependent effect in liver tissue slices and achieving the maximum effect at 400 μM, while the significant enhancement was found after 500 μM treatment on the hepatocyte nuclei. Conclusion: This study suggests that ROS generated in cells may achieve its physiological and pathological effects via biophotonic emissions, which provides a new quantum biological mechanism of ROS, while the detailed clarification requires further research.
文摘Spindle fiber attachments (SFAs) were enriched in a fraction of nuclei isolated from mouselivers. The enrichment method combines sonication, treatment with 2 mol/L NaCl and highspeed centrifugation. SFA was enriched 27-fold on the average (n = 4) when measured byradioimmunoassay. The basic method offers opportunities for further increases of yield andfor the enrichment of SFA uf other vertebrates.
基金supported by the National Basic Research Program of China(2013CB910802,2012CB910602,2010CB912704)National High Technology Research and Development Program of China (2012AA020201,2012AA020202)+1 种基金State Key Project Specialized for Infectious Diseases of China (2012ZX10002-012)National Natural Science Foundation of China (30700990,20975024,31000379)
文摘The liver proteome can serve as a reference to better understand both disease mechanisms and possible therapeutics,since the liver is an important organ in the body that performs a large number of tasks.Here we identify the organelle proteome of C57BL/6J mouse liver nuclei as a promising strategy to enrich low abundance proteins,in the sense that analysis of whole liver cells is rather complex for current techniques and may not be suitable for proteins with low abundance.Evaluation of nucleus integrity and purity was performed to demonstrate the effectiveness of the optimized isolation procedure.The extracted nuclear proteins were identified by 2-DE MS analyses,and a total of 748 proteins were identified.Bioinformatic analyses were performed to demonstrate the physicochemical properties,cellular locations and functions of the proteins.
