Activation and regulation of the pattern recognition receptors in obesity-induced adipose tissue inflammation and insulin resistance.
Obesity-associated chronic tissue inflammation is a key contributing factor to type 2 diabetes mellitus, and a number of studies have clearly demonstrated that the immune system and metabolism are highly integrated. Recent advances in deciphering the various immune cells and signaling networks that link the immune and metabolic systems have contributed to our understanding of the pathogenesis of obesity-associated inflammation. Other recent studies have suggested that pattern recognition receptors in the innate immune system recognize various kinds of endogenous and exogenous ligands, and have a crucial role in initiating or promoting obesity-associated chronic inflammation. Importantly, these mediators act on insulin target cells or on insulin-producing cells impairing insulin sensitivity and its secretion. Here, we discuss how various pattern recognition receptors in the immune system underlie the etiology of obesity-associated inflammation and insulin resistance, with a particular focus on the TLR (Toll-like receptor) family protein Radioprotective 105 (RP105)/myeloid differentiation protein-1 (MD-1).
Department of Immunobiology and Pharmacological Genetics, Graduate School of Medicine and Pharmaceutical Science for Research, University of Toyama, 2630 Sugitani, Toyama-shi, Toyama 930-0194, Japan. ynagai@med.u-toyama.ac.jp.
Yasuharu
Y
Watanabe
Yoshinori
Y
Nagai
Kiyoshi
K
Takatsu
D000273:Adipose Tissue / Q000473:pathology*; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D000954:Antigens, Surface / Q000378:metabolism; D004195:Disease Models, Animal; D006801:Humans; D007107:Immune System / Q000378:metabolism; D007249:Inflammation / Q000209:etiology / Q000473:pathology*; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D053474:Nod1 Signaling Adaptor Protein / Q000378:metabolism; D053473:Nod2 Signaling Adaptor Protein / Q000378:metabolism; D009765:Obesity / Q000150:complications / Q000473:pathology*; D051192:Receptors, Pattern Recognition / Q000378:metabolism*; D015398:Signal Transduction; D051197:Toll-Like Receptor 4
D015703:Antigens, CD; D000954:Antigens, Surface; C092722:CD180 protein, human; D007328:Insulin; C115213:LY86 protein, human; C119067:NOD1 protein, human; C429018:NOD2 protein, human; D053474:Nod1 Signaling Adaptor Protein; D053473:Nod2 Signaling Adaptor Protein; D051192:Receptors, Pattern Recognition; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4