关键词: 肥胖, 肠道菌群, 学龄前儿童

Abstract: Objective To investigate the changes in gut microbiota in preschool obese children and their association with body mass index (BMI),and help further study on prevention and therapy of obesity. Methods Twenty-nine obese preschool children aged 3~6 years old and 34 normal-weight children with similar age and sex ratio from 2 kindergartens in Beijing in 2014,were included in the study.Microbial DNA was extracted from the morning fecal samples and the V4-V5 region of the bacteria 16S ribosomal RNA gene were amplified by PCR.Then the Illumina MiSeq sequencing was used to examine the gut microbiota. Results Compared to the normal-weight children (6.42%±1.10%),the level of Proteobacteria (10.75%±2.00%) was significantly increased in obese children (P<0.05); whereas no changes were found in levels of Firmicutes (2.90%±10.79% vs.62.41%±11.59%),Bacteroidetes (19.19%±3.29% vs.16.36%±3.04%),Actinobacteria (9.69%±1.66% vs.9.28%±1.72%),Lactobacillus (0.08%±0.01% vs.0.07%±0.01%),Bacteroides (2.73%±0.47% vs.3.81%±0.71%),Bifidobacterium (8.09%±1.39% vs.8.25%±1.53%) and Escherichia-Shigella (3.94%±0.67% vs.5.78%±1.07%) between the normal-weight and obese groups (P>0.05).Correlative analysis showed that the level of Proteobacteria was positively associated with BMI,and other phyla and genera had no association with BMI (P>0.05). Conclusion The increased Proteobacteria level may play an important role in obesity of preschool children.

Key words: obesity, gut microbiota, preschool children