This 2019 McGill review discussed long-lasting effects of perinatal stress: “Epigenetic processes are involved in embedding the impact of early-life experience in the genome and mediating between social environments and later behavioral phenotypes. Since these phenotypes are apparent a long time after early experience, changes in gene expression programming must be stable. Although loss of … Continue reading The epigenetics of perinatal stress
This 2019 Singapore human study used Diffusion Tensor Imaging on 5-to-17-day old infants to find: “Our findings showed evidence for region-specific effects of genotype and GxE on individual differences in human fetal development of the hippocampus and amygdala. Gene x Environment models outcompeted models containing genotype or environment only, to best explain the majority of … Continue reading Do genes or maternal environments shape fetal brains?
This 2019 Germany/Canada human fetal cell study was a Proceedings of the National Academy of Sciences of the United States of America direct submission: “In a human hippocampal progenitor cell line, we assessed the short- and long-term effects of GC [glucocorticoid] exposure during neurogenesis on messenger RNA expression and DNA methylation profiles. Our data suggest … Continue reading PNAS politics in the name of science
This 2019 US human study attempted to replicate findings of animal studies that associated caregiver behavior with infant DNA methylation of the glucocorticoid receptor gene: “Greater levels of maternal responsiveness and appropriate touch were related to less DNA methylation of specific regions in NR3c1 exon 1F, but only for females. There was no association with … Continue reading Infant DNA methylation and caregiving
I have high expectations of natural science researchers. I assume that their studies will improve over time, and develop methods and experiments that produce reliable evidence to inform us of human conditions. My confidence is often unrealistic. Scientists are people, after all, and have the same foibles as the rest of us. I anticipate that … Continue reading The Not-Invented-Here syndrome
Two items before getting to the review: 94% of rodent genera are naturally uniparental; The Rattus and Mus genera used in almost all rodent research aren’t part of the 6% in which fathers also provide offspring care. This 2018 Australian review subject was paternal intergenerational and transgenerational transmission of biological and behavioral phenotypes per this … Continue reading How well do single-mother rodent studies inform us about human fathers?
This 2018 German human study found: “DNA methylation in a biologically relevant region of NR3C1-1F [glucocorticoid receptor gene] moderates the specific direction of HPA-axis dysregulation (hypo- vs. hyperreactivity) in adults exposed to moderate-severe CT [childhood trauma]. In contrast, unexposed and mildly-moderately exposed individuals displayed moderately sized cortisol stress responses irrespective of NR3C1-1F DNA methylation. Contrary … Continue reading What will it take for childhood trauma research to change paradigms?
This 2017 Georgia human review covered: “Recent studies, primarily focused on the findings from human studies, to indicate the role of DNA methylation in the associations between childhood adversity and cardiometabolic disease in adulthood. In particular, we focused on DNA methylation modifications in genes regulating the hypothalamus-pituitary-adrenal axis as well as the immune system.” Recommendations … Continue reading DNA methylation and childhood adversity
Imagine that you were a parent who puzzled over the mystery of your pre-teen daughter’s hyperactive behavior. Without detailed family medical histories, would anyone recognize this as a preprogammed phenotype? Could anyone trace the daughter’s behavior back to her maternal great-grandmother being treated with glucocorticoids near the end of the second trimester of carrying her … Continue reading Do you have your family’s detailed medical histories?
This 2016 German human study with one subject found: “The hypothalamus to be the primary generator of migraine attacks which, due to specific interactions with specific areas in the higher and lower brainstem, could alter the activity levels of the key regions of migraine pathophysiology.” The subject underwent daily fMRI scans, and procedures to evoke … Continue reading The hypothalamus couples with the brainstem to cause migraines
The subject of this 2016 Italian/New York review was the stress response: “The stress response, involving the activation of the hypothalamic-pituitary-adrenocortical [HPA] axis and the consequent release of corticosteroid hormones, is indeed aimed at promoting metabolic, functional, and behavioral adaptations. However, behavioral stress is also associated with fast and long-lasting neurochemical, structural, and behavioral changes, … Continue reading A one-sided review of stress
This 2016 review by Eric Nestler, a well-known and well-funded researcher, entitled Transgenerational Epigenetic Contributions to Stress Responses: Fact or Fiction? concluded: “Further work is needed to understand whether and to what extent true epigenetic inheritance of stress vulnerability adds to the well-established and powerful influence of genetics and environmental exposures in determining an individual’s … Continue reading What is epigenetic inheritance?
A 2016 commentary A trilogy of glucocorticoid receptor actions that included two 2015 French rodent studies started out: “Glucocorticoids (GCs) belong to a class of endogenous, stress-stimulated steroid hormones. They have wide ranging physiologic effects capable of impacting metabolism, immunity, development, stress, cognition, and arousal. GCs exert their cellular effects by binding to the GC … Continue reading Lifelong effects of stress
This 2015 French/Italian rodent study found: “Chronic systemic treatment with carbetocin [unavailable in the US] in PRS [prenatally restraint stressed] rats corrected: the defect in glutamate release, anxiety– and depressive-like behavior, and abnormalities: in social behavior, in the HPA response to stress, and in the expression of stress-related genes in the hippocampus and amygdala. These … Continue reading Treating prenatal stress-related disorders with an oxytocin receptor agonist
This 2015 UK human review discussed: “The progress that has been made by studies that have investigated the relationship between depression, early trauma, the HPA axis and the NR3C1 [glucocorticoid receptor] (GR) gene. Gene linkage studies for depression, as well as for other common complex disorders, have been perceived by some to be of only … Continue reading Epigenetic consequences of early-life trauma: What are we waiting for?