PT  - JOURNAL ARTICLE
AU  - Lucas Massier
AU  - Rima Chakaroun
AU  - Shirin Tabei
AU  - Alyce Crane
AU  - Konrad David Didt
AU  - Jörg Fallmann
AU  - Martin von Bergen
AU  - Sven-Bastiaan Haange
AU  - Henrike Heyne
AU  - Michael Stumvoll
AU  - Martin Gericke
AU  - Arne Dietrich
AU  - Matthias Blüher
AU  - Niculina Musat
AU  - Peter Kovacs
TI  - Adipose tissue derived bacteria are associated with inflammation in obesity and type 2 diabetes
AID  - 10.1136/gutjnl-2019-320118
DP  - 2020 Oct 01
TA  - Gut
PG  - 1796--1806
VI  - 69
IP  - 10
4099  - http://gut.bmj.com/content/69/10/1796.short
4100  - http://gut.bmj.com/content/69/10/1796.full
SO  - Gut2020 Oct 01; 69
AB  - Objective Bacterial translocation to various organs including human adipose tissue (AT) due to increased intestinal permeability remains poorly understood. We hypothesised that: (1) bacterial presence is highly tissue specific and (2) related in composition and quantity to immune inflammatory and metabolic burden.Design We quantified and sequenced the bacterial 16S rRNA gene in blood and AT samples (omental, mesenteric and subcutaneous) of 75 subjects with obesity with or without type 2 diabetes (T2D) and used catalysed reporter deposition (CARD) – fluorescence in situ hybridisation (FISH) to detect bacteria in AT.Results Under stringent experimental and bioinformatic control for contaminants, bacterial DNA was detected in blood and omental, subcutaneous and mesenteric AT samples in the range of 0.1 to 5 pg/µg DNA isolate. Moreover, CARD-FISH allowed the detection of living, AT-borne bacteria. Proteobacteria and Firmicutes were the predominant phyla, and bacterial quantity was associated with immune cell infiltration, inflammatory and metabolic parameters in a tissue-specific manner. Bacterial composition differed between subjects with and without T2D and was associated with related clinical measures, including systemic and tissues-specific inflammatory markers. Finally, treatment of adipocytes with bacterial DNA in vitro stimulated the expression of TNFA and IL6.Conclusions Our study provides contaminant aware evidence for the presence of bacteria and bacterial DNA in several ATs in obesity and T2D and suggests an important role of bacteria in initiating and sustaining local AT subclinical inflammation and therefore impacting metabolic sequelae of obesity.