Severe Depression Affects Men & Women Differently? New Study Explains Why

A team of researchers from the Université Laval may have discovered why severe depression affects men and women differently.

Representational images (Source: Getty)

New Delhi: A team of researchers may have discovered why severe depression affects men and women differently. The study conducted by scientists from the Université Laval in Québec City, Canada, was recently published in the Nature Communications journal. 

The researchers studied the brains of people suffering from depression at the time of death. They found alterations located in different parts of the brain for each sex, the study said.

The researchers also identified a potential depression biomarker in women. 

In a statement issued by the Université Laval, Caroline Ménard, the lead author of the study, and professor at Université Laval, said that depression is very different between men and women. 

Depression Symptoms & Antidepressant Response Different In Men & Women

Ménard explained that the disease is twice as common in women, the symptoms are different, and the response to antidepressants is not the same as in men. The scientists' goal was to find out the reason behind this.

Caroline Ménard's team had shown in a previous study that prolonged social stress in male mice weakened the blood-brain barrier separating the brain from peripheral blood circulation. The loss of a protein called claudin-5 is responsible for these changes. 

Also, the changes were evident in the nucleus accumbens, a part of the brain associated with reward and the control of emotions. 

The same thing was observed in the brains of men suffering from depression at the time of their death.

Professor Ménard and her team repeated the same experiment in female mice, and found that the brain barrier alterations caused by claudin-5 loss were located in the prefrontal cortex. 

The scientists' findings were the same when they examined the brains of women suffering from depression at the time of their death.

However, in men, the blood-brain barrier of the prefrontal cortex was not affected, the study found.

Professor Ménard said that the prefrontal cortex is involved in mood regulation, but also in anxiety and self-perception. 

This part of the brain was unaltered in chronically stressed male mice and in men with depression, she added.

The findings suggest that chronic stress alters the brain barrier differently according to gender, she explained.

Blood-Marker Linked To Brain Health At Higher Concentrations In Stressed Women

The researchers investigated further and discovered a blood marker linked to brain barrier health. They found the marker at higher concentrations in the blood of stressed female mice.

The marker, called soluble E-selectin, is an inflammatory molecule and is also present in blood samples of women with depression, but not in men, according to the study.

Ménard said that depression is still diagnosed through questionnaires, and that their group is the first to show the importance of neurovascular health in depression and to suggest soluble E-selectin as a depression biomarker.

She explained that it could potentially be used to screen for and diagnose depression, and could also be used to measure the efficacy of existing treatments or treatments in development.

She said that large-cohort clinical studies must be conducted to confirm the biomarker's reliability. 

She said the breakthroughs would not have been possible without the individuals and families who donate to the Douglas Bell Canada Brain Bank and the Signature Bank in Montréal. The Douglas Bell Canada Brain Bank has 3,500 human brain specimens.