A whole-genome expression screen on the postmortem brains of 6 individuals who had posttraumatic stress disorder (PTSD) and 6 healthy controls revealed that a particular protein, serum and glucocorticoid regulated kinase 1 (SGK1), was reduced in expression by more than 80% in the prefrontal cortices (PFC) of PTSD-affected brains relative to healthy controls (Licznerski P et al. PLoS Biol. 2015;13:e1002282).
When investigators at Yale University School of Medicine and their colleagues experimentally reduced the protein’s activity in the PFC of rats, the animals exhibited PTSD-like behavior, including decreased avoidance of discomfort (ie, helpless-like behavior) and enhanced memory of conditioned contextual fear responses (ie, impaired fear inhibition).
Hampton T. Low Levels of Brain Protein Linked to PTSD. JAMA. 2015;314(21):2226. doi:10.1001/jama.2015.16091