Effect Of Perinatal Iron Deficiency On Behavioral Developments And Myelination Around Hippocampus In Rat Pups

ObjectiveIron deficiency is one of the most common nutritional disorders. Pregnant women and young children are particularly vulnerable to iron deficiency. This study is designed to determine the consequences of perinatal iron deficiency on behavioral developments and on myelination of specific brain region after dietary iron treatment in rats.MethodsSixteen female SD rats were randomly assigned to iron-sufficient (CN) or low-iron (ID) diets during gestation and lactation [postnatal days (PND) 1-21]. Thereafter, all offspring including 86 CN pups and 70 ID pups were fed the iron-sufficient diet. They were assessed for cognitive and behavioral development and myelination around the hippocampus. Behavioral assessments included general motor function; sensorimotor function (surface righting reflex, negative geotaxis reflex and vibrissae-evoked forelimb placing test); recognition memory task (novel object recognition task); and spatial memory task (T maze alteration task). The density of myelination around hippocampus was visualized with immunohistochemical staining for 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase, marker of oligodendrocyte ) and quantified by analysis of mean optical density (MOD) . The regions of interest included the corpus callosum andthe fimbria of hippocampus.ResultsCompared with control rats, iron-deficient rats showed behavioral deficits in bar-hang test;sensorimotor function and recognition memory (novel object recognition task), while nosignificant differences were found in the spatial memory task (T maze test) performed atPND 70. Iron-deficient animals showed an overall weaker definition in white matterformation compared with controls at 25 days of age. Significantly reduced density ofmyelination was found in iron-deficient rats(MOD: 0.2689 ± 0.0470) compared withcontrol rats (MOD: 0.4811±0.0810) in the corpus callosum, but no difference wasshowed in the fimbria of hippocampus relative to control rats.ConclusionThese studies show that perinatal iron deficiency can significantly alter the behavioraloutcomes in rat pups. Perinatal iron deficiency in early life can profoundly influences thedevelopment of myelination in the corpus callosum around hippocampus region.Hypomyelination may partly be responsible for the abnormal behavioral outcomes.