Research led by the State University of Campinas (Unicamp) identified a set of proteins linked to late depression, a disease that affects the elderly. Molecules have been determined that may contribute to more effective diagnoses and treatments. The study, which was published in the European Journal of Proteomics, also involves scientists from the universities of Connecticut (USA) and Toronto (Canada), in addition to the Federal University of Minas Gerais (UFMG).
Daniel Martins-de-Souza, a professor at Unicamp and coordinator of the work, highlights that one of the objectives is to understand the similarity with depression. “We still have no idea how similar, from a molecular point of view, this depression is to major depression, which affects almost 10% of the population. And, in the same way as [ocorre] for major depression, we don’t have biomarkers that can identify or predict that someone will develop it in the future”, he points out.
One of the differences between the two manifestations of the disease may be linked to the environmental aspect. “That is, people go through life experiences that end up driving biological changes that lead to depression. This is also true for major depression, but these features may be more prominent in people with late-term depression. According to the World Health Organization (WHO), at least six out of every 100 people between the ages of 65 and 74 will be diagnosed with depression.
analysis
Blood samples from 50 people were studied, 19 of whom were diagnosed with late-term depression. The analysis showed significant differences in the concentration of 96 proteins. Among them, 75 are candidates for determining a molecular identity for geriatric disease.
“We managed to find what we call a molecular signature. In other words, we identified some molecules in the blood that would have this power to distinguish who has depression and who does not”, pointed out Martins-de-Souza.
The next steps of the study involve collecting new samples from this population. The idea is to “specifically quantify these 75 proteins to see if we can replicate these data”, explains the coordinator.
In addition, doctoral student Lícia Silva-Costa, from the Neuroproteomics Laboratory at Unicamp and one of the authors of the study, identified six proteins that have a correlation with the severity of symptoms. “It can also be a marker to predict that a person will have a very large worsening of symptoms, which could be previously treated”, adds the professor. The proposal now is also to validate this information with new samples.