Effects of Tanreqing injection on the gut microbiota in healthy volunteers.

Objectives: Many studies have confirmed that antibacterial agents can disrupt the human gut microbiota. In China, Tanreqing injection (TRQ) is a drug with antibacterial activity that is widely used in the treatment of respiratory infections. However, its specific influence on gut microbiota remains unclear. This study aimed to investigate the effect of TRQ on the gut microbiota of healthy volunteers.

Methods: Twelve healthy adults received 20 ml of TRQ intravenously daily for 7 consecutive days. At six timepoints (Pre, on D1, D3, D5, D7 and follow-up visit) fecal samples were collected and analyzed using 16S rRNA gene sequencing.

Results: Eleven people were included in the analysis finally. TRQ did not significantly alter gut microbiota diversity or richness (Shannon and Simpson and Chao1 index) in healthy people during the intervention. Gut microbial structure was stable (weighted and unweighted Unifrac). Using a machine learning method based on PLS-DA analysis, the separation trend on D7 at the genus level was found, returning to baseline two days after discontinuation. The abundance of major genus fluctuated on D7 compared with that prior to treatment, including an increase of unclassified_f_Enterobacteriaceae (13.0611%), a decrease of Bifidobacterium and Escherichia-Shigella (6.887%, 10.487%). Functional prediction analysis did not reveal any significant difference.

Conclusions: Our study showed short-term use of TRQ at conventional doses may not cause perturbations to the gut microbiota in healthy adults. This finding provides some useful information for the safe use of TRQ in the treatment of respiratory infections.

Clinical trial registration: https://www.medicalresearch.org.cn/, identifier MR-31-24-014367.