Developmental origin of abnormal dendritic growth in the mouse brain induced by in utero disruption of aryl hydrocarbon receptor signaling

作者：Kimura Eiki; Kubo Ken ichiro; Matsuyoshi Chieri; Benner Seico; Hosokawa Mayuko; Endo Toshihiro; Ling Wenting; Kohda Masanobu; Yokoyama Kazuhito; Nakajima Kazunori; Kakeyama Masaki; Tohyama Chiharu^*

来源：Neurotoxicology and Teratology, 2015, 52: 42-50.

DOI：10.1016/j.ntt.2015.10.005

• Aryl hydrocarbon receptor
• Dendrite
• Developmental neurotoxicity
• Dioxin
• Hippocampus
• Spine

Increased prevalence of mental disorders cannot be solely attributed to genetic factors and is considered at least partly attributable to chemical exposure. Among various environmental chemicals, in utero and lactational dioxin exposure has been extensively studied and is known to induce higher brain function abnormalities in both humans and laboratory animals. However, how the perinatal dioxin exposure affects neuromorphological alterations has remained largely unknown. Therefore, in this study, we initially studied whether and how the overexpression of aryl hydrocarbon receptor (AhR), a dioxin receptor, would affect the dendritic growth in the hippocampus of the developing brain. Transfecting a constitutively active AhR plasmid into the hippocampus via in utero electroporation on gestational day (GD) 14 induced abnormal dendritic branch growth. Further, we observed that 14-day-old mice born to dams administered with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD; dose: 0, 0.6, or 3.0 mu g/kg) on GD 125 exhibited disrupted dendritic branch growth in both the hippocampus and amygdala. Finally, we observed that 16-month-old mice born to dams exposed to perinatal TCDD as described above exhibited significantly reduced spine densities. These results indicated that abnormal micromorphology observed in the developing brain may persist until adulthood and may induce abnormal higher brain function later in life.

• 出版日期2015-12