The January issue of the journal Neuron outlines a new neurologic research method that has uncovered a novel mechanism for stress adaptation. This has allowed researchers at the Weizmann Institute of Science (Israel) to better understand how chronic stress can lead to psychiatric disorders like depression and anxiety.
Exposure to a stressful stimulus typically initiates a cascade of neurochemical effects. The release of corticotropin-releasing hormone (CRH) triggers CRH genes to produce even more, creating a self-reinforcing loop. Coupled with the adaptive nature of this mechanism, over time, normal CRH function will give way to chronic dysfunction.
CRH is a well-known player in the "fight-or-flight" stress reflex, but little is known about how the hormone regulates its own gene expression. The Israeli team used mice and zerbafish to identify the protein Orthopedia (Otp) as the key molecular regulatory mechnism for CRH genes. In fact, long-term adaptation to stress cannot occur without the presence of Otp. The protein amounts to an "On/Off switch" for CRH, said researchers.
Proper regulation of the stress response is a delicate balancing act. Over- and under-activation can be equally damaging over time, so for the Weizmann group to advance our understanding of the chemical chain reactions taking place in times of stress means we are one step closer to safe, effective interventions, undertaken before stress-related psychiatric problems become pronounced or irreversible.
Source: The Weizmann Institute of Science, Israel
