Hormones and behavior
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Hormones and behavior · Sep 2020
Pubertal recalibration of cortisol-DHEA coupling in previously-institutionalized children.
As a period of heightened plasticity, puberty may provide a window of opportunity for recalibration of the hypothalamic-pituitary-adrenal (HPA) axis to current conditions. Our group has recently documented evidence for pubertal recalibration of HPA axis reactivity among children internationally adopted as infants from institutions into supportive, well-resourced homes. As a first step at examining potential mechanisms by which puberty may facilitate recalibration of the HPA axis, the current study assessed whether previously-institutionalized (PI) children differed from non-adopted (NA) comparison children in levels of the adrenal steroid hormone dehydroepiandrosterone (DHEA) and in its intra-individual covariation (coupling) with cortisol by adrenal pubertal stage. ⋯ For NA children, post-stressor cortisol and DHEA were positively coupled across sessions at all average adrenal pubertal stages. For PI children who were, on average, at earlier adrenal pubertal stages, post-stressor cortisol and DHEA were not coupled, but PI children who were at later pubertal stages demonstrated positive cortisol-DHEA coupling similar to that of the NA children. We suggest that these findings provide insights into processes which may underlie pubertal recalibration of the HPA axis.
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Hormones and behavior · May 2018
ReviewPrenatal paracetamol exposure and child neurodevelopment: A review.
The non-prescription medication paracetamol (acetaminophen, APAP) is currently recommended as a safe pain and fever treatment during pregnancy. However, recent studies suggest a possible association between APAP use in pregnancy and offspring neurodevelopment. ⋯ Together, these nine studies suggest an increased risk of adverse neurodevelopmental outcomes following prenatal APAP exposure. Further studies are urgently needed with; precise indication of use and exposure assessment of use both in utero and in early life. Given the current findings, pregnant women should be cautioned against indiscriminate use of APAP. These results have substantial public health implications.
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Hormones and behavior · Nov 2017
Progesterone improves neurocognitive outcomes following therapeutic cranial irradiation in mice.
Despite improved therapeutic methods, CNS toxicity resulting from cancer treatment remains a major cause of post-treatment morbidity. More than half of adult patients with cranial irradiation for brain cancer develop neurobehavioral/cognitive deficits that severely impact quality of life. We examined the neuroprotective effects of the neurosteroid progesterone (PROG) against ionizing radiation (IR)-induced neurobehavioral/cognitive deficits in mice. ⋯ Western blot analysis of hippocampal and cortical tissue showed that IR at both doses induced astrocytic activation (glial fibrillary acidic protein), reactive macrophages/microglia (CD68) and apoptosis (cleaved caspase-3) and PROG treatment inhibited these markers of brain injury. There was no significant difference in the degree of deficit in any test between the two dose regimens of IR at either time point. These findings could be important in the context of patients with brain tumors who may undergo radiotherapy and eventually develop cognitive deficits.
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Hormones and behavior · Jul 2017
Male song sparrows have elevated testosterone in response to neighbors versus strangers.
Upon hearing a conspecific signal, animals must assess their relationship with the signaller and respond appropriately. Territorial animals usually respond more aggressively to strangers than neighbors in a phenomenon known as the "dear enemy effect". This phenomenon likely evolved because strangers represent a threat to an animal's territory tenure and parentage, whereas neighbors only represent a threat to an animal's parentage because they already possess a territory (providing territory boundaries are established and stable). ⋯ Contrary to our prediction, we found that song sparrows had higher testosterone levels after exposure to neighbor playback compared to stranger playback. We discuss several explanations for our result, notably that corticosterone may regulate the dear enemy effect in male song sparrows and this may inhibit plasma testosterone. Future studies will benefit from examining corticosterone in addition to testosterone, to better understand the hormonal underpinnings of the dear enemy effect.