RUDN University Geneticist Name Possible Active Components of “Antidepressant Bacteria”
RUDN University geneticist summarized the results of research on probiotics, which in the future can be used to treat depression. The analysis helps identify the problems due to which probiotic-based antidepressants have not yet been created, and to identify possible components that explain the therapeutic effect of probiotics. The results are published in Nutrients.
Most antidepressants have side effects: from insomnia to digestive problems. One of the possible solutions is probiotic microorganisms. They are used as medicines, dietary supplements, and food products. Some studies show that probiotics can be used to treat depression. Even though only a few strains have been proved effective and their clinical effect has not yet been proven, probiotics are considered a promising direction for the treatment of depression. It is assumed that they will have no side effects that classical antidepressants have. The geneticist of RUDN University summarized the research data and identified existing problems in this direction. The results will help make new anti-depression drugs available. This is especially true in the era of the COVID-19 pandemic, when the number of depressions is increasing.
"Since antidepressants are effective only in a subset of patients and are also plagued by their infamous side effects—insomnia, fatigue, anxiety, confusion, gastrointestinal symptoms, dry mouth, skin redness, itch and photophobia—there is an ever-increasing demand for safer drugs. In addition, COVID-19 pandemic poses a great threat to public health, mainly due to a panoply of troubling side effects observed in millions of people recovering from the disease including depression. Thus, there is an urgent need for adequate rehabilitation programs. This problem could be solved with the help of probiotics. We have summarized the data of clinical studies of probiotics that have antidepressant properties and identified potential genes and proteins that underlie these mechanisms", Professor Valery Danilenko from RUDN University.
Geneticists have studied about a hundred of papers on the use of probiotics for the treatment of depressive disorders and have identified several problems that require attention. First, all clinical studies that confirmed the effectiveness of probiotics in the fight against depression were conducted on an insufficiently large sample. Secondly, most studies are aimed at only a small number of probiotics, mainly bacteria of the genus Lactobacillus and Bifidobacterium. In addition, most of the research is carried out only on animals.
The main problem as the RUDN University genetics concluded, is lack of studies that determine the mechanism of the antidepressant effect of probiotics. The existing data is inconclusive and fragmented. At the same time, the active components of bacterial cells make up a large and diverse set, which has not been sufficiently studied. It includes compounds secreted by bacteria and components of their cell walls. For example, c-aminobutyric acid, which is produced by intestinal bacteria, alleviates the symptoms of depression and anxiety—this has been proven in several animal studies. RUDN geneticists are developing an antidepressant based on strains that produce γ-aminobutyric acid. Another possible mechanism is the release of hydrogen peroxide by some microorganisms. This is probably how the L. Reuteri bacterium causes an antidepressant effect. Another possible active component is the enzyme carboxylesterase, the 5-kDa protein, the STP peptide and other compounds.
"Despite the disparity between studies attempting to pinpoint the bacterial putative genes and proteins accounting for these mechanisms, they ultimately show that bacteria are a potential source of metabiotics—microbial metabolites or structural components. Since the constituents of cells—namely, secreted proteins, peptides and cell wall components—are most likely to be entangled in the gut–brain axis, they can serve as starting point in the search for probiotics with concrete properties", Professor Valery Danilenko from RUDN University.
More information:
Elena Poluektova et al, The Putative Antidepressant Mechanisms of Probiotic Bacteria: Relevant Genes and Proteins, Nutrients (2021). DOI: 10.3390/nu13051591
Provided by RUDN University
