Comparison Of Oxidative Stress Between Iodine Deficiency And Iodine Deficiency On Iodine Deficiency In NOD.H-2 ^H4 Mice

Objective: To compare the effect of iodine excess and herbs with iodine excesson the oxidative injury and the antioxidation effect in iodine-deficiency andautoimmune thyroiditis-susceptible mice and to investigate its mechanism.Method:8-week-old NOD.H-2h4female mice were made into common animal model ofsusceptible autoimmune thyroiditis and iodine deficiency induced goiter byfeeding a low iodine diet and double distilled water within90days. Then theywere randomly divided into four groups: the normal control group (NC), the modelcontrol group (MC), herbs with iodine excess group (HIE) and the iodine excessgroup (IE). After90days of treatment, the morphology of thyroid cells wereobserved under optical microscopy. The contents of serum glutathione peroxidase(GSH-Px), superoxide dismutase (SOD), malondialdehyde (MDA) and hydrogenperoxide (H2O2) were measured by the biochemical method. The expression of4-hydroxynonenal (4-HNE) in the thyroid was detected by the immunohistochemistrymethod. The expression of peroxide oxidation reduction enzyme5(PRDX5) in thethyroid was detected by the Western blotting and immunohistochemistry method.Result:1.Compared with the NC group, the activity of serum GSH-Px in the IE groupdecreased significantly,that in the MC group also decreased (P<0.05) while nosignificant difference was seen in the HIE group(P>0.05). There was nosignificant difference among each group about the activity of serum SOD (P>0.05).2.Compared with the NC group, the contents of serum MDA and H2O2in the IE groupincreased significantly (P<0.01) while no significant difference was seen inthe HIE group(P>0.05). The contents of serum MDA in the HIE group were lowerthan that in the IE group (P<0.05). Compared with the NC group, the contentsof serum MDA and H2O2in the MC group significantly decreased (P<0.05).3.Compared with the NC group, the expression of4-HNE in the HIE group and the IE group increased obviously (P<0.001,). The expression of PRDX5in the thyroidin the HIE group increased more significantly than that in the NC group and theIE group(P<0.05).Conclusions：1.Iodine excess caused oxidative injury to NOD.H-2h4and induced autoimmunethyroiditis.2.Compared with iodine excess, herbs with iodine excess caused more slightoxidative injury and obviously enhanced antioxidant capacity in NOD.H-2h4mice.