Dormivigilia

Today we had another job candidate seminar for the joint Biological Science/Psychology tenure-track faculty hire (and I still can’t resist the university food services cookies….I’ll have more tomorrow…..). The candidate, Dr. Patrick McGowan, was from the Douglas Institute at McGill University. He studies epigenetic  (environmental and genetic interactions) contributions to suicide risk in humans and to stress resiliency in rodents. Regarding his human research, his neuronal locus of interest is the hippocampus, obtained from a brain bank, of males who committed suicide and were additionally abused/neglected during childhood (test group). His control group was males who died of natural (heart attack) or tragic (car accident) causes and were not abused/neglected during childhood. Upon analysis of these brains using microarrays, McGowan found hyper DNA methylation in the victims who committed suicide and were previously abused. In follow-up experiments, McGowan and colleagues discovered that this DNA methylation association with suicide was specific for abused/neglected males, as suicidal males who were not abused/neglected did not possess this extent of DNA methylation. Therefore, upon further advancements in genetic/neurotechnology, we may soon be able to identify markers of DNA methylation that infer suicide risk, particularly in individuals who have a history of physical, emotional, sexual abuse/neglect.

As for McGowan’s rodent studies which investigated epigenetic contributions to stress resiliency (or lack thereof), he specifically focused on early-life maternal care. There is an extensive amount of rodent literature showing that anxious, ambivalent, and neglectful mothers (usually identified by low frequencies of licking young, which provides the litter with nourishment) have young that are less resilient to stress later in life. Knowing this, McGowan et al. illustrated that these low-licked offspring, whether raised by their biological or adopted low-licking mothers, had reduced expression of glucocorticoid receptors, which is positively correlated with physiological stress, and hyper DNA methylation at specific gene loci.

Here’s Dr. McGowan’s recent paper in Nature Neuroscience. Really cool work

He also mentioned that diet may influence the onset/severity of DNA methylation. Broccoli is one anti-methylation (and antioxidant) food. No wonder why I had the craving for broccoli and cavatelli (heavy pasta bathed in EVOO, garlic, fresh Parmaesan (emphasis on fresh) cheese,
and broccoli).

And…..his presentation was certainly NOT one of these……this video is hilarious but sadly true……

McGowan, P., Sasaki, A., D’Alessio, A., Dymov, S., Labonté, B., Szyf, M., Turecki, G., & Meaney, M. (2009). Epigenetic regulation of the glucocorticoid receptor in human brain associates with childhood abuse Nature Neuroscience, 12 (3), 342-348 DOI: 10.1038/nn.2270