The intrauterine programming of hypothalamic-pituitary-adrenal (HPA) axis hypersensitivity is associated with chronic adult diseases. Our previous studies demonstrated the HPA-axis hypersensitivity in offspring rats induced by prenatal nicotine exposure. The goal of the present study is to further investigate the intrauterine programming mechanism. Pregnant Wistar rats were subcutaneously administered with 2.0 mg/kg day of nicotine from gestational day (GD) 9-20. A group of the pregnant rats was euthanized at GD20, and the fetal rats were extracted. The remaining rats were left to come to term, and the adult offspring were exposed to chronic stress. For adult offspring rats, prenatal nicotine exposure induced HPA-axis hypersensitivity after chronic stress, accompanied by imbalanced glutamatergic/GABAergic afferent inputs. Moreover, prenatal nicotine exposure enhanced the expression of hippocampal glutamic acid decarboxylase 67 (GAD67), accompanied by a decreased methylation ratio within nt -1019 to -689 of the GAD67 promoter, decreased expression of Dnmt1, and an increased GABA content and density of GABAergic neurons. The fetal rats exhibited changes consistent with the adult rats. Similar effects were also observed by treating the fetal hippocampal cell line H19-7 with 1-100 μM nicotine, while dihydro-β-erythroidine hydrobromide (DHβE), the specific inhibitor of α4β2nAChR, can reverse the effects caused by nicotine. These results indicate that prenatal nicotine exposure can enhance the potential excitability of the hypothalamus via the intrauterine programming of up-regulation of hippocampal GAD67. All of these results contribute to the HPA-axis hypersensitivity in adult offspring.
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http://dx.doi.org/10.1007/s00204-017-1996-8 | DOI Listing |
JAMA Netw Open
December 2024
Department of Psychological and Brain Sciences, Washington University in St Louis, Missouri.
Importance: The extent to which neuroanatomical variability associated with early substance involvement, which is associated with subsequent risk for substance use disorder development, reflects preexisting risk and/or consequences of substance exposure remains poorly understood.
Objective: To examine neuroanatomical features associated with early substance use initiation and to what extent associations may reflect preexisting vulnerability.
Design, Setting, And Participants: Cohort study using data from baseline through 3-year follow-up assessments of the ongoing longitudinal Adolescent Brain Cognitive Development Study.
Children (Basel)
November 2024
Department of Radiology, University of Washington, Seattle, WA 98195, USA.
Pregnant women have limited information on the impact of prenatal cannabis exposure (PCE) alone. Our aim was to determine if PCE, without alcohol, tobacco, or illicit drug use, is associated with altered birth outcome measures in obstetrically low-risk women. In this observational cohort study, pregnant women were recruited between 2019 and 2022 from communities in Washington and Oregon, USA, and enrolled following their first trimester.
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December 2024
Addiction Research Group, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada.
Introduction: Prenatal nicotine exposure (PNE) from maternal smoking disrupts regulatory processes vital to fetal development. These changes result in long-term behavioral impairments, including mood and anxiety disorders, that manifest later in life. However, the relationship underlying PNE, and the underpinnings of mood and anxiety molecular and transcriptomic phenotypes remains elusive.
View Article and Find Full Text PDFFront Neural Circuits
January 2025
Department of Molecular and Cellular Physiology, Shinshu University School of Medicine, Matsumoto, Japan.
Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficits in social interaction and communication, along with restricted and repetitive behaviors. Both genetic and environmental factors contribute to ASD, with prenatal exposure to valproic acid (VPA) and nicotine being linked to increased risk. Impaired adult hippocampal neurogenesis, particularly in the ventral region, is thought to play a role in the social deficits observed in ASD.
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