Abstract:

Abstract:Objective To study  the effects of low dose radiation (LDR) on the expressions of intercellular adhesion molecule-1 (ICAM-1) mRNA and protein in kidney of diabetes mellitus (DM) mice and  illuminate that anti-inflammation of LDR is a main mechanism for diabetic therapy.Methods The healthy and right age C57BL/6J mice were divided into 4 groups including control,DM,LDR and DM/LDR.The mice in DM and DM/LDR groups were injected intraperitoneally with streptozocin (STZ) to set up DM models.The mice in DM/LDR and LDR groups were irradiated with 25 mGy every other day for 4 weeks.The expressions of ICAM-1 mRNA and protein in kidney were detected with RT-PCR and Western blotting 2,4,8,12 and 16 weeks after irradiation.Results The expressions of ICAM-1 mRNA and protein in kidney had no significant difference among 4 groups before LDR (P>0.05).The expressions of ICAM-1 mRNA and protein 2 weeks after irradiation with LDR were higher than those in the other 3 groups (P<0.05).The expressions of ICAM-1 mRNA and protein in the DM/LDR group 4 weeks after irradiation were also  significantly  higher than those in non-DM groups (P<0.05),but still
 significantly  lower than those in DM group (P<0.05),and the significant differences were kept to 16 weeks after irradiation.But the expressions of ICAM-1 mRNA and protein in LDR group were significantly higher than those in  control group(P<0.05).IHC assay showed that the glomerular and tubular in DM and DM/LDR groups were abnormal and the quantities of the positive staining cells were significantly increased compared with non-DM groups.However the damage of glomerular and tubular in DM/LDR was significantly supressed compared with DM gorup and the positive staining cells were also decreased.Conclusion  Under the circumstance of DM,LDR can significantly decrease the expressions of ICAM-1 mRNA and protein in mouse kidney to relief the inflammation reaction in kidney;but in normal condition,LDR can improve the immunity and promote the release of immune-related factors.It means that LDR can play different roles under different circumstance.

Key words: low dose radiation;intercellular adhesion molecule-1;diabetes mellitus;diabetic nephropathy;inflammation