The gut microbiota and its relationship with obese children

Sammanfattning: Background: It’s decelerated that childhood obesity is a global epidemic since 21st century. General obesity has doubled since 1980 and comes with a distinct increase of mobility and mortality. Obesity also correlate with future consequences in form of different diseases such as metabolic syndrome, cancer and increased risk of chronic diseases and not to mention the increased cost for the society. The condition is undoubtable multifactored and the precise mechanism behind are still incomplete. Previous studies have suggested an indirect pathogenicity of methanogens, favouring other microbes’ growth and in that way correlate in obesity. In this work the aim was to further investigate this possible correlation by analysing levels of methanogens in obsese and lean children. The analysis was made directly in faecal samples and after incubation of feaces in a nutrient solution. The hypothesis was that a small but important difference in methanogenic levels between lean and obese children exist but might be too low to be statistically proven and that an incubation allowing growth of the methanogens would ease the detection and result in a stronger signal. Methods: The participants in the study was assigned to lean- or obese group depending on S-BMI, a total of 29 participants. Faecal samples and anthropometrical data were collected from the two groups. Levels of methanogens in feaces, non-incubated and after 48h anaerobic incubation in a nutrient solution, was determined by quantitative PCR targeting the 16S-ribosomal RNA. Methanogen groups included in the analysis was Methanobacteriales (MBT), Methanosaetaceae (MST), Methanosarcinaceae (MSC) and Methanomicrobiales (MMB). Results and conclusion: The results showed a general low abundance of methanogen quantification in the different groups, except for the MBT group. The abundance of MSC, MMB and MST were at the point for detection, making the results quite uncertain. MBT however, were well detected and specific for its selected primers. Furthermore, a correlation between BMI and MBT was significantly lower in the obese group compared to the lean group in the non-incubated samples, and an even greater significance was seen in the incubated samples. The incubation aspect is unique for this study and according to hypothesis highlighted a significant correlation between levels of MBT and BMI. Further studies are needed to understand the importance of methanogens and their activity on effects of diet and obesity in childhood.