title: Role and function of macrophages in the metabolic syndrome.
abstract: Macrophages are key innate immune effector cells best known for their role as professional phagocytes, which also include neutrophils and dendritic cells. Recent evidence indicates that macrophages are also key players in metabolic homoeostasis. Macrophages can be found in many tissues, where they respond to metabolic cues and produce pro- and/or anti-inflammatory mediators to modulate metabolite programmes. Certain metabolites, such as fatty acids, ceramides and cholesterol crystals, elicit inflammatory responses through pathogen-sensing signalling pathways, implicating a maladaptation of macrophages and the innate immune system to elevated metabolic stress associated with overnutrition in modern societies. The outcome of this maladaptation is a feedforward inflammatory response leading to a state of unresolved inflammation and a collection of metabolic pathologies, including insulin resistance, fatty liver, atherosclerosis and dyslipidaemia. The present review summarizes what is known about the contributions of macrophages to metabolic diseases and the signalling pathways that are involved in metabolic stress-induced macrophage activation. Understanding the role of macrophages in these processes will help us to develop therapies against detrimental effects of the metabolic syndrome.
authors.affiliation: Department of Genetics and Complex Diseases, Department of Nutrition, Division of Biological Sciences, Harvard School of Public Health, 665 Huntington Ave, Boston, MA 02115, U.S.A.
authors.forename: Prerna
authors.initials: P
authors.lastname: Bhargava
authors.forename: Chih-Hao
authors.initials: CH
authors.lastname: Lee
mesh_terms: D016207:Cytokines / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D007249:Inflammation / Q000209:etiology / Q000276:immunology / Q000378:metabolism; D018836:Inflammation Mediators / Q000378:metabolism; D007333:Insulin Resistance; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D024821:Metabolic Syndrome / Q000209:etiology / Q000276:immunology / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators