Adipose Natural Killer Cells regulate Adipose Tissue Macrophages to Promote Insulin Resistance in Obesity

Lee et al. Cell Metabolism (2016) 23, 685-98.

Speaker: Yi-Sheng Jiang (江翊生)                               Time: 14:00~15:00, Oct. 19, 2016

Commentator: Dr. Yau-Sheng Tsai (蔡曜聲老師)       Place: Room 601

Abstract:

Many diseases are associated with obesity. Recent studies suggest that obesity-induced inflammation underlies the development of insulin resistance. This notion is supported by the observation that obesity increases inflammation in adipose tissue by elevating pro-inflammatory gene expression.¹ Previous studies have shown that obesity-induced inflammation and insulin resistance are reduced in genetically altered mouse models in which pro-inflammatory pathways are suppressed. These results suggest that obesity-induced inflammation in adipose tissue is mediated by interaction of resident immune cells.² In this study, the authors show that natural killer (NK) cells play a critical role in the development of obesity-induced insulin resistance and inflammation, which is indicated by increasing glucose and insulin concentrations in the blood and enhancement of the production of pro-inflammatory cytokines, notably TNFα. Furthermore, adipose tissue macrophages that comprise 40%-60% of the immune cells in adipose tissue are thought to be the primary effector cells in obesity is partly regulated by NK cells.³ Collectively, these results indicate that adipose NK cells affect obesity-induced inflammation by producing pro-inflammatory mediators and contribute to the development of obesity-induced insulin resistance.

References:

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