Brain organoid model shows molecular signs of Alzheimer’s before birth

In a model of human fetal brain development, Emory researchers can see perturbations of epigenetic markers in cells derived from people with familial early-onset Alzheimer’s disease, which takes decades to appear. This suggests that in people who inherit mutations linked to early-onset Alzheimer’s, it would be possible to detect molecular changes in their brains before birth. The results were published in the journal Cell Reports. “The beauty of using organoids is that they allow us to Read more

The earliest spot for Alzheimer's blues

How the most common genetic risk factor in AD interacts with the earliest site of neurodegeneration Read more

Make ‘em fight: redirecting neutrophils in CF

Why do people with cystic fibrosis (CF) have such trouble with lung infections? The conventional view is that people with CF are at greater risk for lung infections because thick, sticky mucus builds up in their lungs, allowing bacteria to thrive. CF is caused by a mutation that affects the composition of the mucus. Rabindra Tirouvanziam, an immunologist at Emory, says a better question is: what type of cell is supposed to be fighting the Read more

FKBP5

Striking graph showing gene-stress interactions in PTSD

This graph, from a recent paper in Nature Neuroscience, describes how variations in the gene FKBP5 make individuals more susceptible to physical and sexual abuse, and thus more likely to develop PTSD (post-traumatic stress disorder).nn.3275-F1

The paper is the result of a collaboration between Elisabeth Binder and her colleagues at the Max Planck Institute of Psychiatry in Munich, and Emory psychiatrists Kerry Ressler and Bekh Bradley. The population under study is made up of inner-city Atlanta residents, part of the Grady Trauma Project overseen by Ressler and Bradley. This paper analyzes samples from a group of individuals that is more than twice as large as the original 2008 paper defining the effect of FKBP5, and adds mechanistic understanding: how regulation of the FKBP5 gene is perturbed.

Back to the graph — in addition to the effects of the different forms of the gene, it is striking how high the rate of PTSD is for both individuals with the protective and risk forms of FKBP5. Also, for individuals who did not experience abuse, the PTSD rate is actually higher for the “protective” form of the gene. On this point, the authors write:

It is, however, possible that the described polymorphisms Gafas Ray Ban outlet define not only risk versus resilience, but possibly environmentally reactive versus less reactive individuals. This would imply that the so-called risk-allele carriers may also profit more from positive environmental change.

The FKBP5 gene encodes a protein that regulates responses to the stress hormone cortisol. Thus, it acts in blood and immune system cells, not only the brain, and is involved in terminating the stress response after the end of a threat. In the paper’s discussion, the authors propose that FKBP5 may have a role in sensitivity to other immune and metabolic diseases, in addition to PTSD and depression.

Max Planck press release on Binder paper

Recent post on Shannon Gourley’s related work (how stress hormone exposure leads to depression)

 

 

Posted on by Quinn Eastman in Neuro Leave a comment