Research reveals the role of genetics in stress and immunity

A new study, carried out by a joint effort between UK and Italian researchers, provides new insights into the biological mechanisms that cause major depressive disorder (MDD), particularly in the role of the immune system.

The study looked specifically at gene expression, the way in which the instructions carried in our genes are expressed, which influence the body’s functions. The work is published in the newspaper Molecular Psychiatry.

About 1 in 3 people with depression have elevated levels of inflammation, immune system function, our body’s defense against potentially harmful substances, such as infections. During stress, inflammation is used to effectively fight off threats, and it is likely that this is the reason why the immune system works in depression, which is a chronic stress condition.

People with depression and inflammation have a higher risk of not responding to standard antidepressants, and may benefit from additional treatments that target the immune system, such as anti-inflammatories. Therefore, understanding the biological mechanisms that support increased inflammation may also shed light on ways to help people with depression, especially those who do not respond to conventional antidepressants.

“Depression, like almost every medical condition, is one size does not fit all. Understanding the diversity of people with depression also means recognizing patterns. As the field of precision medicine advances, psychiatry must keep pace,” says Dr. Luca Sforzini, IoPPN of the King.

The researchers used a technology called “mRNA sequencing” to measure the activity of all the genes in the blood. This study found that people with depression who had increased levels of inflammation showed increased activation of genes related to the immune system and metabolic function.

The study found that even with moderately increased inflammation, there is significant activation of genes associated with the immune system. People with stress and very high levels of increased inflammation have increased activity of genes involved in metabolic processes, that is, related to the process that we produce, in which use and store energy, which is important, for example, in the functions of fat and sugar in the body.

Professor Annamaria Cattaneo says: “When we use genetics, we can find something different from what doctors see, something ‘in between’ between what is in our genes and what finally appears. .

In that study, the researchers also found a specific genetic profile in people who responded successfully to antidepressants, with changes in biological processes that do not only inhibit immune function. but also brain protection, suggesting that these viruses. programs may play a role in helping these people recover from stress and the way antidepressants work.

Overall, the present study demonstrates the importance of gene expression in understanding the biology of depression and antidepressant action. Our genes and their associated biological processes may explain the differences between different types of depression, such as those who do or do not respond to conventional antidepressants, or those who do or do not. tend to have medical consequences such as diabetes and heart problems.

Professor Carmine Pariante says: “Our study highlights the need to understand the biological basis of different types of stress, to leave the traditional approach, to approaches that are aimed at the individual.”