A correlation study of intestinal microflora and first-episode depression in Chinese patients and healthy volunteers

This research examines the intestinal-associated flora of patients with depression compared with healthy volunteers to identify the characteristics and differences of flora associated with depression. It provides a theoretical basis for the prevention and treatment of depression through intestinal micro-ecological regulation.

We recruited 30 patients with depression to participate in the patient group (PG), and 30 volunteers were recruited for the healthy control group (HG) from the Beijing Hui-long-guan Hospital. Thereafter, the 16S rRNA high-throughput sequencing method, using the Hamilton Depression Scale, was applied to analyze patient and healthy groups.

PG and HG microflora were different regarding phylum, Family, Genus, and Order. The results showed that Barnesiella was the dominant flora in depression patients, while Lachnospiraceae and Alloprevotella were the dominant bacteria in healthy participants. The proportion of Betaproteobateria (Proteobacteria), Alcaligenaceae (proinflammatory), Peptostreptococcaceae, Catenibacterium, Romboutsia, Sutterella, and Burkholderiales in the anxiety-negative depressed group was significantly higher than in the anxiety-positive group; and the proportion of Anaerostipes (inflammation) and Faecalibacterium (anti-inflammatory) bacteria was significantly lower than that of patients with anxiety.

Results showed there were differences in intestinal micro-ecology between patients with depression and healthy volunteers. We found that the level of inflammation-related bacteria in anxiety-positive patients was lower than that in anxiety-negative patients. These results enrich the knowledge of relationships between depression and intestinal flora and provide a theoretical basis for probiotics to assist in the treatment of depression.