Intestinal flora structure of obese Mongolian children based on DGGE and real-time PCR

Objective To compare the intestinal flora of Mongolian children with different body mass index (BMI) in a certain area of Baotou city.Methods A cluster sampling method was used to investigate 410 Mongolian children aged 7 to 12 years old in Baotou City.Each weight category group (obesity, overweight and normal weight) included 30 cases and age-, sex-matched30 control children.The fecal genomic DNA was extracted by the kit method.The diversity of intestinal flora of Mongolian children with different BMI groups was analyzed by PCR-DGGE.The real-time PCR was used to detect the dominant bacteria in intestinal tract, including Bacteroides, Clostridium, Bifidobacterium and Lactobacillus.Results PCR-DGGE electrophores showed that there were differences in the composition of intestinal flora of Mongolian children with different BMI groups.The species richness of obesity group (7.40± 0.55) was significantly lower than that of normal body weight group (11.00 ± 1.22) and overweight group (12.40±2.51) (P<0.05); the Shannon diversity index of obese group (1.92±0.07) was lower than that of normal body weight group (2.29±0.10) and overweight group (2.33± 0.21) (P< 0.05).Results of real-time PCR showed that with the increase of BMI, the number of Bifidobacterium and Bacteroidesin in different BMI groups of Mongolian children decreased (P<0.05), while the number of Clostridium increased (P<0.05).There was no significant difference in the number of Lactobacillus among the three groups (P>0.05).Conclusion There are differences in the composition of intestinal fiora of Mongolian children with different BMI groups.It suggests that intestinal flora may be involved in the occurrence and development of obesity in Mongolian children.