Effects Of Different Iodine Nutritional Status On P38 MAPK-mediated Inflammation In Thyroid Cells

ObjectiveTo investigate the effects of different iodine nutritional status on the inflammatory response mediated by P38/MAPK pathway in human normal thyroid cells and the role of endoplasmic reticulum stress in this process.MethodsCultivate the human normal thyroid cells(Nthy-ori-3-1)in logarithmic growth period in six-well plate.In this study,take it as the object of experimental study when the cells contact with each other and the melting degree up to 100%.They were intervened with different concentrations of iodine and endoplasmic reticulum stress inhibitor 4-PBA,P38/MAPK pathway blocker SB203580.Detecting the expressions of p-P38 PERK,IER1,ATF6 protein by Western-blot.Detecting the expression of MCP-1 mRNA by Real Time PCR.Results1.(1)Relative to the appropriate iodine state.The expression of p-P38 protein and MCP-1 mRNA in ill iodine status(high iodine,low iodine,iodine fluctuating state)was significantly increased(P<0.05).(2)Relative to low iodine state,the expression of p-P38 protein and MCP-1 mRNA in high iodine state increased significantly(P<0.05),(3)There was no significant difference in the expression of p-P38 protein and MCP-1 mRNA between high iodine state and iodine fluctuating state,low iodine state and iodine fluctuating state(P>0.05).(4)The expression of endoplasmic reticulum stress-related proteins(PERK,IER1,ATF6)was roughly the same as that of p-P38 protein in each group.2.(1)Compared with the high iodine group and high iodine +4-PBA group,the iodine fluctuation group and the iodine fluctuation +4-PBA group,the low iodine group and the low iodine +4-PBA group,the expression of endoplasmic reticulum stress-related proteins(PERK,IRE1,ATF6)increased significantly(P<0.05).(2)Compared with the high iodine group and high iodine +4-PBA group,iodine fluctuation group and iodine fluctuation +4-PBA group,low iodine group and low iodine +4-PBA group,the expression of p-P38 protein and MCP-1 mRNA increased significantly(P<0.05).3.(1)Compared with the high iodine group and high iodine +SB203580 group,iodine fluctuation group and iodine fluctuation +SB203580 group,low iodine group and low iodine +SB203580 group,the expression of p-P38 protein and MCP-1 mRNA increased significantly(P<0.05).(2)Compared with the high iodine group and high iodine +SB203580 group,iodine fluctuation group and iodine fluctuation +SB203580 group,low iodine group and low iodine +SB203580 group,the expression of PERK and IRE1 protein increased significantly(P<0.05).Compared with the low iodine group and low iodine +SB203580 group,the expression of ATF6 protein increased significantly(P<0.05),while there was no significant difference in the expression of ATF6 protein between high iodine group and high iodine +SB203580 group,iodine fluctuation group and iodine fluctuation +SB203580 group(P>0.05).Conclusions1.Relative to the appropriate iodine state,the ill iodine status(high iodine,low iodine,iodine fluctuating state)is more likely to up-regulate P38/MAPK pathway,up-regulated the expression of MCP-1,and lead to inflammatory reaction and endoplasmic reticulum stress.The above reactions were more significant in high iodine state than in low iodine state,but there was no significant difference between high iodine state and iodine fluctuating state,low iodine state and iodine fluctuating state.2.Ⅲ iodine status(high iodine,low iodine,iodine fluctuating state)can lead to endoplasmic reticulum stress through the PERK,IRE1 and ATF6 signaling pathways in human normal thyroid cells and the P38/MAPK-mediated inflammatory response pathway can be upregulated by endoplasmic reticulum stress signaling pathway.3.Ⅲ iodine status(high iodine,low iodine,iodine fluctuating state)can up-regulate P38/MAPK in normal human thyroid cells.There are two signal pathways of endoplasmic reticulum stress(PERK and IRE1)could be activated by P38/MAPK pathway,but the endoplasmic reticulum stress ATF6 could not activated by P38/MAPK pathway.(see figure 4.1 for details)...