Abstract:

Objective: To investigate the gut microbiota distribution and antibiotic resistant genes (ARGs) carrying- status in the girls with precocious puberty (PP). Methods: A total of 29 girls were enrolled in the study, including 21 girls with precocious puberty (PP) [11 girls with central precocious puberty (CPP group), 10 girls with premature thelarche (PT group)], and 8 age-matched healthy girls (NC group). The fecal samples were analyzed to explore difference in composition of gut microbiota and ARGs numbers between the PP (CPP+PT) and NC groups using shotgun metagenomic sequencing. Results: The composition and abundance of gut microbiota in the PP girls were different from the NC girls. The relative abundances of top three gut microbiota in CPP, PT and NC girls were 50.03%, 37.73% and 67.61% for Firmicutes, 33.00%, 43.26% and 10.32% for Bacteroidetes, and 4.26%, 4.22% and 11.16% for Actinobacteria. Compared with the NC girls, the PP girls had a significantly higher abundance of Bacteroidetes (P=0.034) and much lower abundance of Firmicutes (P=0.006) and Actinobacteria (P<0.000 1). It revealed that there were 257, 273 and 240 species of ARGs identified in the CPP, PT and NC girls, respectively. The PP girls had more ARGs types and higher abundance of tetracyclines and macrolide ARGs than the NC girls. Conclusions: Compared with the NC girls, the PP girls have a different distribution of gut microbiota and more species of ARGs enriching in tetracyclines and macrolides. It indicates that the dietary and environmental antibiotic exposure may influence the gut microbiota distribution in children, which may be associated with the pathogenesis of PP.

Key words: Central precocious puberty, Premature thelarche, Gut microbiota, Metagenomics, Antibiotic resistant genes