Researchers explain why depression, stress and overeating might have close association

Stress and chronic overeating since a long time has been linked with an increased risk of developing anxiety and depression. Now, a research team at the Yale University has explained why these conditions are linked closely; the researchers have also provided a possible solution to these problems.

During the study, researchers found that anesthetic ketamine is capable of reversing depression symptoms in rats kept on a high-fat diet in a similar way it fights chronic stress-induced synaptic damage and depression in humans.

Three researchers are conducting the said study House Jameson, Ronald S. Duman, the Elizabeth Mears & House Jameson Professor of Psychiatry and Neurology and one the study’s senior author, said that researchers noticed that effects of high fat diet overlap with the impact of chronic stress. Duman added that these effects can act as strong contributing factors for depression and different metabolic disorders like type 2 diabetes.

Through this new study, scientists at Yale have successfully shown that Special K (a widely used pet name for ketamine), which is often abused as a recreational drug, can promptly and dramatically diminish chronic depression symptoms in individuals resistant to the standard antidepressants.

Subsequent research revealed that ketamine works by activating the mTORC pathway. For those who don’t know: the mTORC pathway is responsible for regulating protein synthesis involved in production of our brain’s synaptic connections that get damaged due to depression and stress.

The mTORC pathway also has a role to play in cellular responses to metabolism and energy. Patients with metabolic disorders such as type 2-diabetes also have much higher risk of developing depression.

A team of Yale researchers under the leadership of Sophie Duthell carried out experiments in Duman’s laboratory to find out whether diet can influence the behavior of rodents fed fat, 6 times the normal quantity. The team found that after being on the said diet for four months, pathways responsible for both metabolism and synaptic plasticity got disrupted in the rats. Additionally, the rats started exhibiting signs of anxiety and depression.

The researchers found that all those symptoms got reversed quickly with just a single dosage of ketamine. Ketamine also reversed the disruptions caused in the mTORC pathways.

Duman has, however, cautioned that effects of Special K on metabolism require further research and the dosage of the drug and its use as treatment for depression are still subject to clinical trials.