Fetuses and neonates are known to be high-risk groups for Methylmercury（MeHg）exposure.MeHg can be transferred to the fetus through the placenta and to newborn offspring through breast milk.The aim of the present stu...Fetuses and neonates are known to be high-risk groups for Methylmercury（MeHg）exposure.MeHg can be transferred to the fetus through the placenta and to newborn offspring through breast milk.The aim of the present study was to investigate the neurotoxic effects of low doses of MeHg（1 and 5 μg/m L in drinking water） administration,from gestational day 1 to postnatal day（PND） 21,on the neurobehavioral development of rats.The results showed that the no-observed-effect level of MeHg is somewhere in the range of 1-4 μg/mL.Neurobehavioral development analysis revealed a delayed appearance of cliff drop and negative geotaxis reflexes in the 5 μg/mL MeHg exposure group.Developmental exposure to MeHg affected locomotor activity functions for the females,but not for the males,implying that the female pups were more vulnerable than the male pups.All pups exposed to 5 μg/mL of MeHg showed a significant deficit in motor coordination in the rotarod test compared with controls,and the highest accumulated concentrations of Hg were found in the cerebellum,followed by the hippocampus and cerebral cortex,indicating that the cerebellum is a possible target for MeHg toxicity.We demonstrated adverse effects of developmental exposure to MeHg associated with tissue concentrations very close to the current human body burden of this persistent and bioaccumulative compound.展开更多
The developmental coordination disorder(DCD)is characterized by an impaired motor coordination skill for age impacting day-life motor activities and academic achievement of children.DCD has been classified as neurodev...The developmental coordination disorder(DCD)is characterized by an impaired motor coordination skill for age impacting day-life motor activities and academic achievement of children.DCD has been classified as neurodevelopmental disorder in DSM-5[1].DCD prevalence has been estimated ranging about 5–6%worldwide,but without a recognized causative hypothesis apart from the so-called“dual stream hypothesis”,which suggests a separation in cerebral pathways involved in perception and action,and the known relationship with executive functions(EF)impairments.In 2023,the systematic review by Fogel et al.provided an evidence of weak-to-strong relationships between motor skills and EFs among individuals with DCD[2].Moreover,the low birth weight and/or the preterm birth have been identified as the most relevant causative factors for DCD and probably for other neurological disorders included epilepsy and for neurodevelopmental disorders(NDDs).展开更多
基金financially supported by the National Natural Science Foundation of China (No.21177087)the National Program on Key Basic Research Project of China (973 Program) (No.2013CB430005)
文摘Fetuses and neonates are known to be high-risk groups for Methylmercury（MeHg）exposure.MeHg can be transferred to the fetus through the placenta and to newborn offspring through breast milk.The aim of the present study was to investigate the neurotoxic effects of low doses of MeHg（1 and 5 μg/m L in drinking water） administration,from gestational day 1 to postnatal day（PND） 21,on the neurobehavioral development of rats.The results showed that the no-observed-effect level of MeHg is somewhere in the range of 1-4 μg/mL.Neurobehavioral development analysis revealed a delayed appearance of cliff drop and negative geotaxis reflexes in the 5 μg/mL MeHg exposure group.Developmental exposure to MeHg affected locomotor activity functions for the females,but not for the males,implying that the female pups were more vulnerable than the male pups.All pups exposed to 5 μg/mL of MeHg showed a significant deficit in motor coordination in the rotarod test compared with controls,and the highest accumulated concentrations of Hg were found in the cerebellum,followed by the hippocampus and cerebral cortex,indicating that the cerebellum is a possible target for MeHg toxicity.We demonstrated adverse effects of developmental exposure to MeHg associated with tissue concentrations very close to the current human body burden of this persistent and bioaccumulative compound.
文摘The developmental coordination disorder(DCD)is characterized by an impaired motor coordination skill for age impacting day-life motor activities and academic achievement of children.DCD has been classified as neurodevelopmental disorder in DSM-5[1].DCD prevalence has been estimated ranging about 5–6%worldwide,but without a recognized causative hypothesis apart from the so-called“dual stream hypothesis”,which suggests a separation in cerebral pathways involved in perception and action,and the known relationship with executive functions(EF)impairments.In 2023,the systematic review by Fogel et al.provided an evidence of weak-to-strong relationships between motor skills and EFs among individuals with DCD[2].Moreover,the low birth weight and/or the preterm birth have been identified as the most relevant causative factors for DCD and probably for other neurological disorders included epilepsy and for neurodevelopmental disorders(NDDs).
