ABSTRACT
<p><b>OBJECTIVE</b>To explore effects of iron overload on hematopoiesis in mice with bone marrow injury and its possible mechanism (s).</p><p><b>METHODS</b>C57BL/6 mice were divided into control, iron, irradiation, irradiation+iron groups. The iron-overloaded model of bone marrow injury was set up after mice were exposed to the dose of 4 Gy total body irradiation and (or) were injected iron dextran intraperitoneally. Iron overload was confirmed by observing iron deposits in mice and bone marrow labile iron pool. Additionally, the number of peripheral blood and bone marrow mononuclear cells and the frequency of erythroid cells and myeloid cells were counted and hematopoietic function was assessed.</p><p><b>RESULTS</b>(1)Iron overload occurred by bone marrow biopsy and flow cytometry analysis. (2)Compared with control group, the number of platelets [(801.9±81.2)×10⁹/L vs (926.0±28.2)×10⁹/L] and BMMNC and the frequency of erythroid cells and myeloid cells decreased. Moreover, hematopoietic colony forming units and single-cell cloning counts decreased significantly in irradiation group (P<0.05). (3)Compared with irradiation group, the number of platelets [(619.0±60.9)×10⁹/L vs (801.9±81.2)×10⁹/L] and the frequency of erythroid cells and myeloid cells decreased; moreover, hematopoietic colony forming units and single-cell cloning counts decreased significantly in irradiation+iron group (P<0.05). (4)Compared with irradiation group, ROS level increased by 1.94 fold in BMMNC, 1.93 fold in erythroid cells and 2.70 fold in myeloid cells, respectively (P<0.05).</p><p><b>CONCLUSION</b>The dose of 4 Gy total body irradiation caused bone marrow damage and iron overload based on this injury model, which could damage bone marrow hematopoietic function aggravatingly. And further study found that iron overload was closely related to increased ROS level in BMMNC. The findings would be helpful to further study the injury mechanism of iron overload on the hematopoiesis of bone marrow.</p>
Subject(s)
Animals , Mice , Bone Marrow , Wounds and Injuries , Bone Marrow Cells , Cell Biology , Hematopoiesis , Iron Overload , Mice, Inbred C57BLABSTRACT
CYP2E1 enzyme encoded by cyp2e1 gene plays an important role in metabolism of heterogeneous organics in mammalian liver cells. The transgenic plant with cyp2e1 can metabolize various low molecular weight organic pollutants. However, it is unclear the mechanism of expression control of cyp2e1 in transgenic plant. In this study, plasmid pSLD50-6 with cyp2e1 and pKH200 with gus as control were transformed into Agrobacterium tumefaciens GV3101 separately. Then, the cyp2e1 or gus genes were transferred into tobacco (Nicotiana tabacum) and the transgenic plants were regenerated via Agrobacterium tumefaciens method. Real-time quantitative PCR (qRT-PCR) was used to analyze the cyp2e1 gene expression. The expression of cyp2e1 in transgenic tobacco with cyp2e1 decreased obviously treated by ethyl alcohol and reduced slightly by benzene and toluene, while it enhanced by acetone, formaldehyde and oxygen deficit in different levels. In addition, the gene expression of NADPH-P450 oxidoreductase and cytochrome b5 enzyme in the transgenic tobacco with cyp2e1 were increased significantly treated by benzene, which showed that NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic tobacco have relation with CYP2E1 detoxication process. It suggested that the NADPH-P450 oxidoreductase and cytochrome b5 enzyme in transgenic plant formed the requirement in mammalian and participated in the electron transport chain of CYP2E1 enzyme catalytic process.