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Champagne, F. A.

Publications and source records attributed to Champagne, F. A..

6 recordsLinked to original sources

Postnatal maternal care impacts hypothalamic Esrrg gene expression, co-expression profiles, and the DNA methylome in prenatal bisphenol-exposed rats

BackgroundEnvironmental exposures co-occurring during early life have a profound influence on neurodevelopment. Our previous work in rats suggests that postnatal maternal care modulates the effects of prenatal exposure to bisphenols, an estrogenic endocrine disrupting chemical, on offspring neurodevelopment. Elevated maternal licking/grooming and prenatal bisphenol exposure have opposing effects on estrogen receptor expression in the medial preoptic area (MPOA), which could impact expression of estrogen-responsive genes. We hypothesized that maternal licking/grooming would mitigate the effects of prenatal bisphenol exposure on estrogen receptor signaling in the developing MPOA. In addition, we hypothesized that there would be interactive effects of prenatal bisphenol exposure and maternal licking/grooming on DNA methylation nearby estrogen responsive elements. ResultsOur results suggest that maternal licking/grooming normalized prenatal bisphenol-induced upregulation of estrogen-related receptor gamma (Esrrg) expression in female pups. These mitigating impacts were also evident in co-expression gene profiles that were enriched for estrogen-responsive genes. DNA methylation analyses indicated that maternal licking/grooming levels influenced the number of differentially methylated regions for prenatal bisphenol-exposed pups. These differentially methylated regions were enriched for binding sites for transcription factors that are known to interact with estrogen receptors. Finally, supplemental "licking-like" tactile stimulation normalized the DNA methylome in prenatal bisphenol-exposed female pups, with an increase and normalization of ESRRG binding to ESRRG-responsive genes. ConclusionsThese results identify a novel biological mechanism in which maternal licking/grooming can mitigate the negative neurodevelopmental impacts of prenatal bisphenol exposure and provides a proof-of-concept for postnatal tactile stimulation as a potential intervention strategy to improve neurodevelopmental outcomes.

genomics↗

Postnatal maternal care moderates the effects of prenatal bisphenol exposure on offspring neurodevelopmental, behavioral, and transcriptomic outcomes

Bisphenols (BPs), including BPA and "BPA-free" structural analogs, are commonly used plasticizers that are present in many plastics and are known endocrine disrupting chemicals. Prenatal exposure to BPA has been associated with negative neurodevelopmental and behavioral outcomes in children and rodent models. Prenatal BPA exposure has also been shown to impair postnatal maternal care provisioning, which can also affect offspring neurodevelopment and behavior. However, there is limited knowledge regarding the biological effects of prenatal exposure to bisphenols other than BPA and the interplay between prenatal BP exposure and postnatal maternal care on adult behavior. The purpose of the current study was to determine the interactive impact of prenatal BP exposure and postnatal maternal care on neurodevelopment and behavior. Our findings suggest that the effects of prenatal BP exposure on eye-opening, adult attentional set shifting and anxiety-like behavior in the open field are dependent on maternal care in the first five days of life. Interestingly, maternal care might also attenuate the effects of prenatal BP exposure on eye opening and adult attentional set shifting. Finally, transcriptomic profiles in male and female medial prefrontal cortex and amygdala suggest that the interactive effects of prenatal BP exposure and postnatal maternal care converge on estrogen receptor signaling and are involved in biological processes related to gene expression and protein translation and synthesis. Overall, these findings indicate that postnatal maternal care plays a critical role in the expression of the effects of prenatal BP exposure on neurodevelopment and adult behavior. Understanding the underlying biological mechanisms involved might allow us to identify potential avenues to mitigate the adverse effects of prenatal BP exposure and improve health and well-being in human populations.

neuroscience↗

Automated Maternal Behavior during Early life in Rodents (AMBER) pipeline

Mother-infant interactions during the early postnatal period are critical for infant survival and the scaffolding of infant development. Rodent models are used extensively to understand how these early social experiences influence neurobiology across the lifespan. However, methods for measuring postnatal dam-pup interactions typically involve time-consuming manual scoring, vary widely between research groups, and produce low density data that limits downstream analytical applications. To address these methodological issues, we developed the Automated Maternal Behavior during Early life in Rodents (AMBER) pipeline for quantifying home-cage maternal and mother-pup interactions using open-source machine learning tools. DeepLabCut was used to track key points on rat dams (32 points) and individual pups (9 points per pup) in postnatal day 1-10 video recordings. Pose estimation models reached key point test errors of approximately 4.1-10 mm (14.39 pixels) and 3.44-7.87 mm (11.81 pixels) depending on depth of animal in the frame averaged across all key points for dam and pups respectively. Pose estimation data and human-annotated behavior labels from 38 videos were used with Simple Behavioral Analysis (SimBA) to generate behavior classifiers for dam active nursing, passive nursing, nest attendance, licking and grooming, self-directed grooming, eating, and drinking using random forest algorithms. All classifiers had excellent performance on test frames, with F1 scores above .886. Performance on hold-out videos remained high for nest attendance (F1=.990), active nursing (F1 =.828), and licking and grooming (F1=.766) but was lower for eating, drinking, and self-directed grooming (F1=.534-.554). A set of 242 videos was used with AMBER and produced behavior measures in the expected range from postnatal 1-10 home-cage videos. This pipeline is a major advancement in assessing home-cage dam-pup interactions in a way that reduces experimenter burden while increasing reproducibility, reliability, and detail of data for use in developmental studies without the need for special housing systems or proprietary software.

animal behavior and cognition↗

Sex-specific effects of chronic paternal stress on offspring development are partially mediated via mothers.

Paternal stress exposure is known to impact the development of stress-related behaviors in offspring. Previous work has highlighted the importance of sperm mediated factors, such as RNAs, in transmitting the effects of parental stress. However, a key unanswered question is whether mothers behavior could drive or modulate the transmission of paternal stress effects on offspring development. Here we investigate how chronic variable stress in Balb/C mice influences the sex-specific development of anxiety- and depression-like neural and behavioral development in offspring. Moreover, we examined how stressed fathers influenced mate maternal investment towards their offspring and how this may modulate the transmission of paternal stress effects on offspring. We show that paternal stress leads to sex-specific effects on offspring behavior. Males that are chronically stressed sire female offspring that show increased anxiety and depression-like behaviors. However, male offspring of stressed fathers show reductions in anxiety- and depression-behaviors and are generally more exploratory. Moreover, we show that females mated with stressed males gain less weight during pregnancy and provide less care towards their offspring which additionally influenced offspring development. These data indicate that paternal stress can influence offspring development directly and indirectly via changes in mothers, with implications for divergent development between male and female offspring.

neuroscience↗

Distinct inflammatory and transcriptomic profiles in dominant versus subordinate males in mouse social hierarchies

Social status is a critical factor determining health outcomes in human and nonhuman social species. In social hierarchies with reproductive skew, individuals compete to monopolize resources and increase mating opportunities. This can come at a significant energetic cost leading to trade-offs between different physiological systems. Particularly, changes in energetic investment in the immune system can have significant short and long-term effects on fitness and health. We have previously found that dominant alpha male mice living in social hierarchies have increased metabolic demands related to territorial defense. In this study, we tested the hypothesis that high-ranking male mice favor energetically inexpensive adaptive immunity, while subordinate mice show higher investment in innate immunity. We housed 12 groups of 10 outbred CD-1 male mice in a social housing system. All formed linear social hierarchies and subordinate mice had higher concentrations of plasma corticosterone (CORT) than alpha males. This difference was heightened in highly despotic hierarchies. Using flow cytometry, we found that dominant status was associated with a significant shift in immunophenotypes towards favoring adaptive versus innate immunity. Using Tag-Seq to profile hepatic and splenic transcriptomes of alpha and subordinate males, we identified genes that regulate metabolic and immune defense pathways that are associated with status and/or CORT concentration. In the liver, dominant animals showed an up-regulation of specific genes involved in major urinary production and catabolic processes, whereas subordinate animals showed an up-regulation of genes promoting biosynthetic processes, wound healing, and proinflammatory responses. In spleen, subordinate mice showed up-regulation of genes facilitating oxidative phosphorylation and DNA repair and CORT was negatively associated with genes involved in lymphocyte proliferation and activation. Together, our findings suggest that dominant and subordinate animals adaptively shift energy investment in immune functioning and gene expression to match their contextual energetic demands. HighlightsO_LIImmunity is shaped by stress and energetic pressures associated with social status C_LIO_LIDominant and subordinate mice favor adaptive and innate immunity, respectively C_LIO_LIDominants increase expression of genes involved in energy production C_LIO_LIWound healing and DNA repair genes are upregulated in subordinates C_LIO_LIGenes related to maintaining and signaling social status are upregulated in dominants C_LI

immunology↗

Robust range of auditory periphery development, eye opening, and brain gene expression in Wistar rat pups that experience variation in maternal backgrounds

The experience of variation in maternal licking and grooming (LG) is considered a critical influence in neurodevelopment related to stress and cognition, but little is known about its relationship to early sensory development. In this study, we used a maternal selection approach to test the hypothesis that differences in LG during the first week of life influence the timing of hearing onset in Wistar rat pups. We performed a range of tests, including auditory brainstem responses (ABR), tracking of eye opening (EO), micro-CT X-ray tomography, and qRT-PCR to monitor neurodevelopmental changes in the female and male progeny of low-LG and high-LG dams. Our results show that variation in maternal LG is not overtly associated with different timing of ABR onset and EO in the progeny. However, the data provide insight on the delay between hearing onset and EO, on key functional and structural properties that define hearing onset at the auditory periphery, and on changes in brain gene expression that include the first evidence that: a) the hypoxia-sensitive pathway is regulated in subcortical and cortical auditory brain regions before hearing onset, and b) implicates maternal LG in regulation of Bdnf signaling in auditory cortex after hearing onset. Altogether, these findings provide a baseline to evaluate how factors that severely disrupt the early maternal environment may affect the expression of robust developmental sensory programs. SIGNIFICANCE STATEMENTEarly life experience during sensitive developmental periods can induce long-term effects on the neurobiological development of the offspring. In the present work we tested the hypothesis that variation in maternal licking and grooming (LG) affects the timing of hearing onset in Wistar rat pups. To our surprise the results did not support the hypothesis. Instead, we found a robust range of early and late auditory development that was independent of maternal LG. Nevertheless, the study provides new findings on the delay between hearing onset and eye opening, on key functional and structural properties that define hearing onset at the auditory periphery, and the first evidence that a) the hypoxia-sensitive pathway is regulated in the central auditory system during the sensitive period before hearing onset, and b) maternal LG is implicated in regulation of Bdnf signaling during the sensitive period after hearing onset. These findings provide a baseline to evaluate how factors that severely disrupt the early maternal environment may affect the expression of robust developmental sensory programs.

neuroscience↗