DNA methylation, and the stress response in the anterior cingulate cortex of abused suicide completers
Bibliographic record
Abstract
Suicide is a major health problem in Canada and around the globe. Studies have shown that individuals with a history of childhood abuse are more likely to commit suicide and neurobiological correlates have been identified in these individuals. Some of these biological changes have included over-activity of stress response pathways in the brain such as the neuroendocrine, hypothalamic pituitary adrenal axis (HPA) and connected networks in the prefrontal cortex like the anterior cingulate cortex (ACC), which affect behaviour. Prior investigations have also shown that epigenetic changes in genes that regulate the HPA can be observed in subjects with a history of child abuse. We investigated DNA methylation in regulatory sites of HPA and related genes, including the corticotrophin releasing hormone (CRH) and its receptors 1 and 2 (CRHR1 and CRHR2), arginine vasopressin (AVP), proopiomelanocortin (POMC), and an intergenic region between AVP and oxytocin, in individuals who died by suicide and had histories of child abuse as compared with controls without histories of abuse. Our findings within the ACC have shown no DNA methylation changes in the areas of the genes we examined; however there was an increase in the expression of CRH and a down regulation of its receptor, CRHR1. These results suggest possible HPA perturbations in our cases, but not through methylation changes in the sequences investigated. These results point to the complexity of epigenetic regulation of genes as an interface with the environment and behaviour and further studies are necessary to explore the role of these genes in the prefrontal cortex and how the environment might affect their molecular regulation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".