A new study, published in Nature Communications, shows how gut bacteria may play a role in depression through the production of neurotransmitters, such as serotonin and glutamate.
Depression is a chronic feeling of sadness, emptiness, or an inability to feel pleasure. The causes of depression are still not fully understood, however, it is likely that various factors are involved, such as:
- genetics
- changes to neurotransmitter levels in the brain
- environmental factors such as exposure to trauma
- psychological and social factors.
What did the study find?
In this study, researchers at Oxford Population Health, working with colleagues in the Netherlands, investigated the relationship between the composition and diversity of the gut microbiota with symptoms of depression.
They examined data from 1,133 participants in the Rotterdam Study. As part of their analysis, they made sure to control for lifestyle factors and medication use. For example, they only included individuals who were not taking antidepressants.
This was to avoid measuring changes in the gut microbiota that are a consequence of the depression — or the medication — rather than a cause.
Various bacteria identified showed a potential involvement in the way people produce neurotransmitters, particularly those linked to depression such as glutamate.
The researchers then replicated and validated these findings using data from another observational study, called the HELIUS study.
The results of this research may one day lead to the development of novel treatments for conditions such as depression.
The role of bacteria
Dr. Najaf Amin, study author and senior research associate at Oxford Population Health, highlighted the key findings to Medical News Today, saying that the research team has “identified 13 types of bacteria [12 genera and one family] associated with depression.”
“Eggerthella, Hungatella, Sellimonas, and Lachnoclostridium are more abundantly found, while Coprococcus, Lachnospiraceae UCG001, Ruminococcusgauvreauii group, Eubacterium ventriosum, Subdoligranulum, Ruminococcaceae (UCG002, UCG003, UCG005), and [the] family Ruminococcaceae were less abundant in individuals with higher symptoms of depression,” she specified.
