title: Macrophage polarization: the answer to the diet/inflammation conundrum?
abstract: Macrophages, a heterogeneous and ubiquitous cell population representing up to 15% of the cellular content of different types of tissue, are the principal cell mediators in response to pathogens, inflammation process, tissue homeostasis and repair and play a pivotal role in atherosclerosis and insulin resistance because of their capacity to be the major source of inflammatory cytokines, which can function through paracrine and endocrine mechanisms. Recently, differently activated macrophage populations have been described, depending on a large variety of microenvironmental signals, and it is now recognized that their activation plays a crucial role in the development and progression of atherosclerosis. There is good evidence of the ability of conjugated linoleic acids and polyphenolic compounds to modulate inflammation in experimental models involving macrophages. This observation leaves room to the intriguing hypothesis that macrophage polarization could represent one of the unifying mechanisms through which specific food components can exert anti-inflammatory effects in humans, contributing to the prevention of chronic diseases strongly linked to inflammation, such as atherosclerosis. Future studies should be addressed to substantiate this hypothesis, investigating whether or not physiological concentrations of food-derived metabolites can perturb macrophage activation in vitro. On the in vivo side, the evaluation of macrophage populations in tissues, however complex, should be included among the analyses performed in observational and intervention studies, in order to understand if macrophage activation is involved in the anti-inflammatory activity of a specific dietary regimen.
authors.affiliation: The φ² Laboratory of Phytochemicals in Physiology, Human Nutrition Unit, Department of Public Health, University of Parma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Dall'Asta
authors.forename: E
authors.initials: E
authors.lastname: Derlindati
authors.forename: D
authors.initials: D
authors.lastname: Ardigò
authors.forename: I
authors.initials: I
authors.lastname: Zavaroni
authors.forename: F
authors.initials: F
authors.lastname: Brighenti
authors.forename: D
authors.initials: D
authors.lastname: Del Rio
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D050197:Atherosclerosis / Q000209:etiology / Q000276:immunology* / Q000378:metabolism / Q000517:prevention & control*; D016207:Cytokines / Q000378:metabolism*; D004032:Diet / Q000009:adverse effects; D005419:Flavonoids / Q000627:therapeutic use; D006801:Humans; D007333:Insulin Resistance; D044243:Linoleic Acids, Conjugated / Q000627:therapeutic use; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology* / Q000378:metabolism; D009369:Neoplasms / Q000276:immunology / Q000378:metabolism; D009765:Obesity / Q000276:immunology / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016207:Cytokines; D005419:Flavonoids; D044243:Linoleic Acids, Conjugated