Frequency of Firmicutes and Bacteroidetes in gut microbiota in obese and normal weight Egyptian children and adults

Abstract

IntroductionObesity and associated metabolic disorders are a worldwide epidemic. Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. The aim of this study was to assess the differences in the composition of the intestinal microbiota between obese and normal weight Egyptian children and adults.Material and methodsThe study included 79 subjects among whom 51 were obese (23 children and 28 adults), and 28 were subjects of normal weight (17 children and 11 adults). Faecal samples were collected from all subjects. Total DNA was extracted from collected stool samples and submitted to conventional PCR for detection of Firmicutes and Bacteroidetes. All the studied group was subjected to clinical and anthropometric evaluation. Laboratory assessment of fasting glucose, high-sensitivity C-reactive protein (hsCRP) and lipid profile was performed.ResultsThe proportions of the phyla Firmicutes and Bacteroidetes were statistically significantly increased in the obese group compared to the normal weight group (p < 0.001, p = 0.003 respectively). The study also found a statistically significant positive trend for higher hsCRP in subjects with positive Firmicutes (p = 0.004). However, no associations were found between positive Bacteroidetes and hsCRP.ConclusionsThe results of this study indicate that obesity in Egyptian children and adults is associated with compositional changes in faecal microbiota with increase in the phyla Firmicutes and Bacteroidetes. This could be considered when developing strategies to control obesity and its associated diseases by modifying the gut microbiota.

Pediatric obesity is associated with an altered gut microbiota and discordant shifts in Firmicutes populations

“…A recent meta-analysis concluded that there were no statistically significant differences across multiple studies in the Firmicutes/Bacteroidetes ratio between obese and normal-weight adults (Walters et al, 2014). In agreement with this meta-analysis, some pediatric studies have Ismail et al, 2011;Payne et al, 2011). Although in our study the Firmicutes/Bacteroidetes ratio was significantly elevated in obese individuals, we observed large variation in the ratio, particularly within the obese group.…”

Pediatric obesity is associated with an altered gut microbiota and discordant shifts in Firmicutes populations

“…A recent meta‐analysis concluded that there were no statistically significant differences across multiple studies in the Firmicutes / Bacteroidetes ratio between obese and normal‐weight adults (Walters et al ., 2014). In agreement with this meta‐analysis, some pediatric studies have found an increase in Firmicutes and a decrease in Bacteroidetes (Bervoets et al ., 2013; Ferrer et al ., 2013) while others have not (Abdallah Ismail et al ., 2011; Payne et al ., 2011). Although in our study the Firmicutes / Bacteroidetes ratio was significantly elevated in obese individuals, we observed large variation in the ratio, particularly within the obese group.…”

High relative abundance of firmicutes and increased TNF-α levels correlate with obesity in children

“…18,19 Similar to our results, an increase in the proportion of these phyla was observed in European and African OW/W children compared to NW children. 9,10,20 However, several studies in adults have found an increase of Bacteroidetes, 21,22 less proportion of Firmicutes, unaltered Bacteroidetes ratio, 23 or no differences in the proportions between these two phyla with the obesity degree. 24,25 In the present study, we found a high relation of Firmicutes/Bacteroidetes in obese children which is consistent with other studies.…”

“…6,8 Recent studies including ours have shown similar findings in obese children. [9][10][11] The risk of OW/O is associated with the high abundance of Firmicutes that is dependent on the high consumption of simple carbohydrates and saturated fats, and low ingestion of micronutrients and fiber. Pro-inflammatory cytokines are known to be increased in serum of subjects with OW/O; particularly, IL-6 and TNF-α (which are also referred as adipokines released by adipocytes), that favor insulin resistance and hypertension.…”