Pushpanathan Premalatha, Srikanth Padma, Seshadri Krishna G, Selvarajan Sribal, Pitani Ravi Shankar, Kumar Thomas David, Janarthanan R
Department of Microbiology, Sri Ramachandra Medical College and Research Institute, Sri Ramachandra University, Porur, Chennai, Tamil Nadu, India.
Department of Endocrinology, Sri Ramachandra Medical College and Research Institute, Sri Ramachandra University, Porur, Chennai, Tamil Nadu, India.
Indian J Endocrinol Metab. 2016 Jul-Aug;20(4):523-30. doi: 10.4103/2230-8210.183474.
Type 2 diabetes mellitus (T2DM) and obesity are associated with changes in gut microbiota and characterized by chronic low-grade inflammation. Monocyte chemoattractant protein-1 (MCP-1) and interferon gamma (IFNγ) are proinflammatory cytokines which play an important role in the development of T2DM. We undertook this study to analyze the gut microbiota of T2DM and nondiabetic subjects and to determine the profile of MCP 1 and IFNγ in the same subjects attending a tertiary care center in Chennai, Tamil Nadu, India.
The study included 30 subjects with clinical details. Stool and blood samples were collected from all the subjects. DNA was extracted from fecal samples and polymerase chain reaction was done using fusion primers. Metagenomic analysis was performed using ion torrent sequencing. The reads obtained were in FASTA format and reported as operational taxonomic units. Human MCP 1 and IFNγ enzyme linked immunosorbent assay (ELISA) were performed for 23 serum samples.
The study consisted of 30 subjects; 17 were T2DM and 13 were nondiabetics. The gut microbiota among T2DM consisted predominantly of Gram negative bacteria; Escherichia and Prevotella, when compared with the nondiabetic group with predominantly Gram positive organisms suchas Faecalibacterium, Eubacterium, and Bifidobacterium. The mean MCP-1 values in the diabetic group were 232.8 pg/ml and in the nondiabetic group 170.84 pg/ml. IFNγ (mean 385.5 pg/ml) was raised in glycated hemoglobin (HbA1c) group of 6.5-7.5% which was statistically significant. Association of Escherichia with T2DM and association of Bifidobacteria in the nondiabetics were also statistically significant.
Escherichia counts were elevated in T2DM with HbA1c of 6.5-8.5% which was statistically significant suggesting that lipopolysaccharides present in the cell wall of Gram-negative bacteria may be responsible for low-grade inflammation as evidenced by elevated MCP-1 and IFNγ levels in T2DM with the same HbA1c levels.
2型糖尿病（T2DM）和肥胖与肠道微生物群的变化相关，并以慢性低度炎症为特征。单核细胞趋化蛋白-1（MCP-1）和干扰素γ（IFNγ）是促炎细胞因子，在T2DM的发生发展中起重要作用。我们开展这项研究，以分析T2DM患者和非糖尿病患者的肠道微生物群，并确定在印度泰米尔纳德邦金奈一家三级医疗中心就诊的同一批患者中MCP-1和IFNγ的情况。
该研究纳入30名有临床详细资料的受试者。采集所有受试者的粪便和血液样本。从粪便样本中提取DNA，并使用融合引物进行聚合酶链反应。使用离子激流测序进行宏基因组分析。获得的读数为FASTA格式，并报告为操作分类单元。对23份血清样本进行人MCP-1和IFNγ酶联免疫吸附测定（ELISA）。
该研究包括30名受试者；17名是T2DM患者，13名是非糖尿病患者。与主要为革兰氏阳性菌（如粪杆菌、真杆菌和双歧杆菌）的非糖尿病组相比，T2DM患者的肠道微生物群主要由革兰氏阴性菌组成，如大肠杆菌和普雷沃氏菌。糖尿病组的平均MCP-1值为232.8 pg/ml，非糖尿病组为170.84 pg/ml。糖化血红蛋白（HbA1c）为6.5 - 7.5%组的IFNγ（平均385.5 pg/ml）升高，具有统计学意义。大肠杆菌与T2DM的关联以及双歧杆菌在非糖尿病患者中的关联也具有统计学意义。
HbA1c为6.5 - 8.5%的T2DM患者中大肠杆菌计数升高，具有统计学意义，这表明革兰氏阴性菌细胞壁中存在的脂多糖可能是低度炎症的原因，同一HbA1c水平的T2DM患者中MCP-1和IFNγ水平升高证明了这一点。
