Damage Effects Of High Iodine On Endothelial Cells From The Rat Aorta Segments

ObjectivesTo research the high iodine effects on endothelial cells from the rat aorta segments via observing the proliferation or apoptosis of iodine with different concentration on them cultured in vitro.MethodsRat aorta segments endothelial cells were cultured under the condition of37℃,5%CO2, saturation humidity. When cells lied in logarithm growth, we divided them into control group and iodized salt group. The latter was divided into8groups with iodine at different concentrations(3506mg/L、4076mg/L、4647mg/L、5218mg/L、5789mg/L、6360mg/L、6931mg/L、7512mg/L). Cells and cell-culture medium were collected after the continuous cultivation of48h. The activity of cells were measured by MTT; the morphologic changes of cells were observed by Wrigh-Giema staining and Acridine Orang staining; the apoptotic percent of cells were measured by the method of flow cytometry; the activity of SOD、GSH-Px and the content of MDA、 GSH and Protein carbonyls in culture were tested; the activity of eNOS and iNOS in the culture were tested; the expression of eNOS-mRNA and iNOS-mRNA were analyzed by RT-PCRICAM-1and VCAM-1productions were measured by ICAM-1ELISA and VCAM-1ELISA. The results were analyzed by one way AN OVA using the SPSS software17.0.Results1the effect of iodine on cell activityCompared with the control group, the results shew that at the dose of3506mg/L-4076mg/L, cells of the iodized salt group grew normally (P>0.05); at the dose of4647mg/L-7512mg/L, cells of the iodized salt group were obviously restrained (P<0.01), and the inhibitory action was positively correlated with the iodine concentration.2Cell Morphology Observation2.1The effect of iodine on cell morphology by Wrigh-Giema stainingCompared with the control group, the results shew that at the dose of3506mg/L-5218mg/L, the amount of cell was normal and no obvious changes of cell morphology could be found. At the dose of5789mg/L-7512mg/L, the amount of cells discreased with iodine contration increasing and cell shrinkage, distortion occurred, even bare nucleus were obersved.2.2The effect of iodine on cell apoptosis morphology by Acridine Orang stainingCompared with the control group, the results shew that at the dose of3506mg/L-4647mg/L, the amount of cell was normal and no obvious changes of cell morphology could be found. At the dose of5218mg/L-7512mg/L, the amount of cells discreased with iodine contration increasing; the nucleoli of cells were distorted and fluorescence fragments gradually increased.3Apoptotic percent of Cells by the method of Flow CytometryCompared with the control group, the results shew that at the dose of4076mg/L or higher, survival rate of cells of the iodized salt group decreased obviously(P<0.01) and survival rate of cells decreased gradually with the iodine concentration increasing. The apoptosis rate of iodized salt group with the iodine concentration of4076mg/L increased obviously (P<0.01).4the effect of iodine on SOD、GSH-Px activity and MDA、GSH and Protein carbonyls contentCompared with the control group, the results shew that at the dose of4076mg/L or higher, the activity of SOD changed significantly(P<0.05or P<0.01); at the dose of3506mg/L or higher, the activity of GSH-Px changed significantly(.P<0.05or P<0.01); at the dose of5789mg/L or higher, the content of MDA increased significantly(P<0.05or P<0.01); at the dose of3506mg/L or higher, the content of GSH discreased significantly(P<0.05or P<0.01), and Protein carbonyls increased significantly(P<0.05or P<0.01).5the effect of iodine on the content of NOS and NOS-mRNA Compared with the control group, the results shew that at the dose of5218mg/L or higher, the activity of eNOS discreased and the expression of eNOS-mRNA were down-regalated significantly(P<0.05or P<0.01). At the dose of3506mg/L or higher, the activity of iNOS increased significantly(P<0.01) and at the dose of3506mg/L or higher, the expression of iNOS-mRNA were up-regalated significantly(P<0.05or P<0.01).6the effect of iodine on the expression of I CAM-1and VCAM-1Compared with the control group, the results shew that at the dose of5789mg/L or higher, the expression of VCAM-1were up-regulated significantly(P<0.05or P<0.01); And at the dose of4076mg/L or higher, the expression of ICAM-1were up-regulated significantly(P<0.05or P<0.01).Conclusion1. Certain concentration of iodine restrains the growth of endothelial cells from the rat aorta segments and it shows a dose-effect relationship.2. High concentration of iodine can change morphology of endothelial cells and lead to cell apoptosis.3. High concentration of iodine can decrease the activity of SOD and GSH-Px, increase the content of MDA and Protein carbonyls and decrease the concent of GSH.4. High concentration of iodine can inhibit the expression of eNOS-mRNA and decease the activity of eNOS. It also can induce the expression of iNOS-mRNA and increase the activity of iNOS.In short, high concentration of iodine can damage endothelial cells and that may be one of mechanisms leading to arterial sclerosis.