MedicalResearch: What are the main findings of the study?
Dr. Basaran: We designed a cross-sectional study to identify the relation between the gut microbiota composition and obesity and diabetes. 27 severely obese individuals (20 men and 7 women with mean BMI: 39.98±5.56 kg/m2), 26 patients with newly diagnosed type 2 diabetes (18 men and 8 women with mean BMI: 28.63±5.08 kg/m2) and 28 healthy control subjects (22 men and 6 women with mean BMI: 23.02±1.70 kg/m2), between 18-65 years of age, were included in the present study. None of the participants was undergoing chronic treatment and no antibiotics, probiotics or prebiotics were taken within 3 months before collecting fecal material. Fecal samples were self-collected in sterile boxes, stored at -80o until analysis, and analyzed by quantitative real-time PCR for the presence of the most common types of intestinal bacteria.
Although tended to increase, we observed no significant difference between the three groups in regards to fecal concentrations of Bacteroidetes. There was also no considerable difference in the fecal Bifidobacteria, Firmicutes and Clostridium Leptum levels among the obesity and diabetes groups. However, Bifidobacteria, Firmicutes and Clostridium Leptum counts were all significantly lower in obese and diabetic patients compared with healthy control individuals. Additionally, logistic regression analysis showed that parameters of adiposity (weight, BMI and waist circumference) and those of glucose control (FBG and HbA1c) were related to the altered gut microbiota composition. This suggests that alterations in the gut microbiota composition may influence metabolic profile in humans.
MedicalResearch: Were any of the findings unexpected?
Dr. Basaran: Studies in humans investigating the association between specific bacterial species and obesity and diabetes reported conflicting results. Some described a positive correlation, some demonstrated an inverse relationship, and others did not find any correlation between intestinal bacterial counts and obesity and diabetes. Thus, we tried to clarify the possible association between our microbial partners and these disorders.
However, further studies should be carried out to elucidate whether the gut microbial changes are a cause or effect of metabolic diseases.
MedicalResearch: What should clinicians and patients take away from your report?
Dr. Basaran: Obesity and diabetes are of the greatest public health challenges of the 21st century and the numbers of those affected continue to rise at an alarming rate. In addition to lifestyle changes (dietary habits and reduced physical activity level) and the genetic susceptibility, changes in the gut microbial composition may also be responsible for that increase. This ‘novel’ partner, named as gut microbiota, consists of at least 10 fold more cells than those in the human body and is predicted to affect the body weight and glucose metabolism.
MedicalResearch: What recommendations do you have for future research as a result of this study?
Dr. Basaran: The manipulation of the intestinal microbiota using probiotics, prebiotics or fecal transplantation may help prevent or even treat diseases such as obesity and type 2 diabetes.
Especially, fecal transplantation is an exciting area of research. Further prospective clinical investigations of fecal microbiota transplantation in patients with obesity and diabetes are needed to confirm this hypothesis.
Abstract presented at International Society of Endocrinology and the Endocrine Society: ICE/ENDO 2014 in Chicago
Gulhane Military Medical Academy School of Medicine
Department of Endocrinology
LB-PP02-1 Comparison of Gut Microbiota in Obese, Diabetic and Healthy Control Individuals