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Temporal and tissue-specific requirements for T-lymphocyte IL-6 signalling in obesity-associated inflammation and insulin resistance.

ABSTRACT: Low-grade inflammation links obesity to insulin resistance through the activation of tissue-infiltrating immune cells. Interleukin-6 (IL-6) is a crucial regulator of T cells and is increased in obesity. Here we report that classical IL-6 signalling in T cells promotes inflammation and insulin resistance during the first 8 weeks on a high-fat diet (HFD), but becomes dispensable at later stages (after 16 weeks). Mice with T cell-specific deficiency of IL-6 receptor-? (IL-6R?^T-KO) exposed to a HFD display improved glucose tolerance, insulin sensitivity and inflammation in liver and EWAT after 8 weeks. However, after 16 weeks, insulin resistance in IL-6R?^T-KO epididymal white adipose tissue (EWAT) is comparable to that of controls, whereas the inflammatory profile is significantly worse. This coincided with a shift from classical T cell IL-6 signalling at 8 weeks, to enhanced IL-6 trans-signalling at 16 weeks. Collectively, our studies reveal that IL-6 action in T cells through classical IL-6 signalling promotes inflammation and insulin resistance early during obesity development, which can be compensated for by enhanced IL-6 trans-signalling at later stages.

SUBMITTER: Xu E

PROVIDER: S-EPMC5418621 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Temporal and tissue-specific requirements for T-lymphocyte IL-6 signalling in obesity-associated inflammation and insulin resistance.

Xu Elaine E Pereira Mafalda M A MMA Karakasilioti Ismene I Theurich Sebastian S Al-Maarri Mona M Rappl Gunter G Waisman Ari A Wunderlich F Thomas FT Brüning Jens C JC

Nature communications 20170503

Low-grade inflammation links obesity to insulin resistance through the activation of tissue-infiltrating immune cells. Interleukin-6 (IL-6) is a crucial regulator of T cells and is increased in obesity. Here we report that classical IL-6 signalling in T cells promotes inflammation and insulin resistance during the first 8 weeks on a high-fat diet (HFD), but becomes dispensable at later stages (after 16 weeks). Mice with T cell-specific deficiency of IL-6 receptor-α (IL-6Rα<sup>T-KO</sup>) expose ...[more]

PMID: 28466852

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Dataset Information

Temporal and tissue-specific requirements for T-lymphocyte IL-6 signalling in obesity-associated inflammation and insulin resistance.

Publications

Temporal and tissue-specific requirements for T-lymphocyte IL-6 signalling in obesity-associated inflammation and insulin resistance.

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