Maternal rat with marginal iodine deficiency affects the expression of brain development related proteins of its offspring / 中华内分泌代谢杂志

ABSTRACT

ObjectiveTo investigate the effects of maternal rat with marginal iodine deficiency on the nerve and intelligence development in its offspring and the related mechanisms.MethodsThe rat model of marginal iodine deficiency was established on the basis of epidemiological characteristics and iodine metabolism characteristics of rats reported in literatures.Marginal iodine deficiency rats were given 3 μg iodine a day ; normal control rats were given 4 μg iodine daily ; iodine deficiency rats were given 1.2 μg iodine daily,respectively.Western blot was used to detect the protein levels of brain derived neurophic factor (BDNF) and early growth response factor 1 ( EGR1 ) in the hippocampus of 7 days newborn rats.Immunohistochemistry was used to measure c-jun and c-fos expressions in the hippocampal CA1 region of 40 days rats.Water maze method was used to measure the ability of learning and spatial memory.Results FT4 level in rats of marginal iodine deficiency group during pregnancy decreased by about 30％.Seven days after birth,the contents of EGR1 and BDNF proteins in the hippocampus of the offspring from marginal iodine deficiency group were significantly decreased compared with normal control group (both P ＜ 0.05 ).Forty-day-old newborn rats in marginal iodine deficiency group also showed significantly decreased c-jun and c-fos expressions in the hippocampal CA1 region ( both P＜0.05 ),along with a decreased trend of spatial learning and memory ability.Conclusions FT4 level will significantly decrease after pregnancy if rats have marginal iodine deficiency,affecting the expression of related proteins in the brain of newborn rats and having a negative impact on offspring brain development.