title: TLR9 regulates adipose tissue inflammation and obesity-related metabolic disorders.
abstract: OBJECTIVE
  Recent studies have revealed a link between Toll-like receptor (TLR) signaling and the adipose tissue inflammation associated with obesity. Although TLR9 is known to play an important role in inflammation and innate immunity, its role in mediating adipose tissue inflammation has not yet been investigated. Thus, the objective of this study was to determine the role of TLR9 in regulating immune cells in visceral adipose tissue and maintaining the metabolic homeostasis.
  
  
  METHODS
  Wild-type and TLR9-deficient mice were fed with a high-fat diet, and the body weight gain, glucose tolerance, insulin sensitivity, and adipose tissue inflammation were examined.
  
  
  RESULTS
  TLR9-deficient mice gained significantly more weight and body fat under a high-fat diet than wild-type mice and exhibited more severe glucose intolerance and insulin resistance. We also found a dramatic increase of M1 macrophages as well as TH 1 cells in the adipose tissue of TLR9-deficient mice compared to wild-type mice. Furthermore, the levels of various proinflammatory cytokines and chemokines were higher in TLR9-deficient mice.
  
  
  CONCLUSIONS
  TLR9 signaling is involved in regulating adipose tissue inflammation and controlling obesity and the metabolic syndrome.
authors.affiliation: Academy of Immunology and Microbiology, Institute for Basic Science, Pohang, Republic of Korea.|Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, POSTECH Biotech Center 244, Pohang, Republic of Korea.
authors.forename: Chun-Pyo
authors.initials: CP
authors.lastname: Hong
authors.affiliation: Academy of Immunology and Microbiology, Institute for Basic Science, Pohang, Republic of Korea.
authors.forename: Chang Ho
authors.initials: CH
authors.lastname: Yun
authors.affiliation: Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, POSTECH Biotech Center 244, Pohang, Republic of Korea.
authors.forename: Gil-Woo
authors.initials: GW
authors.lastname: Lee
authors.affiliation: Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, POSTECH Biotech Center 244, Pohang, Republic of Korea.
authors.forename: Areum
authors.initials: A
authors.lastname: Park
authors.affiliation: Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, POSTECH Biotech Center 244, Pohang, Republic of Korea.|Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea.
authors.forename: You-Me
authors.initials: YM
authors.lastname: Kim
authors.affiliation: Academy of Immunology and Microbiology, Institute for Basic Science, Pohang, Republic of Korea.
authors.forename: Myoung Ho
authors.initials: MH
authors.lastname: Jang
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D059305:Diet, High-Fat; D018149:Glucose Intolerance / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D007249:Inflammation / Q000235:genetics / Q000378:metabolism; D007333:Insulin Resistance / Q000235:genetics*; D050152:Intra-Abdominal Fat / Q000378:metabolism / Q000473:pathology; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D008297:Male; D024821:Metabolic Syndrome / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009765:Obesity / Q000235:genetics*; D015434:Panniculitis / Q000235:genetics* / Q000473:pathology; D051217:Toll-Like Receptor 9 / Q000235:genetics / Q000502:physiology*; D015430:Weight Gain
chemical_list: D016207:Cytokines; C495370:Tlr9 protein, mouse; D051217:Toll-Like Receptor 9