title: Pro-inflammatory chemokines CCL2, chemerin, IP-10 and RANTES in human serum during an oral lipid tolerance test.
abstract: BACKGROUND
  There is a strong coincidence of obesity and a chronic state of modest inflammation. Secretion of pro-inflammatory cytokines from adipocytes and immune cells represents a key mechanism in this process and is affected by fatty acids.
  
  
  METHODS
  A study cohort of 100 overnight fasted healthy volunteers underwent an oral lipid tolerance test (OLTT) by ingestion of 160ml of a protein- and sugar-free lipid emulsion of defined composition. Venal blood was drawn at 0h (fasting) and at 2, 4, and 6h after lipid ingestion. Subjects were characterized by anthropometric and standard laboratory parameters. Serum concentrations of CCL2, IP-10, chemerin, and RANTES were measured by enzyme-linked immunosorbent assay (ELISA). Murine 3T3-L1 adipocytes were stimulated with free fatty acids (FA) and with sex steroids and concentrations of CCL2 and chemerin in cell culture supernatants were measured by ELISA.
  
  
  RESULTS
  A significant reduction of circulating CCL2, IP-10, and chemerin concentrations was observed as a consequence of triglyceride ingestion whereas RANTES levels were increased. CCL2 serum concentrations were positively correlated with resistin and visfatin levels and with LDL/HDL ratio and negatively with adiponectin. There were significant differences in chemerin and RANTES serum concentrations in female and male subjects. CCL2 secretion from 3T3-L1 adipocytes was inhibited by treatment with linoleic (LA) and oleic acid (OA) whereas chemerin secretion was induced. Chemerin release from 3T3-L1 adipocytes was inhibited by testosterone.
  
  
  CONCLUSIONS
  Oral lipid loading is linked to reduced circulating pro-inflammatory chemokines CCL2, IP-10, and chemerin and to increased RANTES levels, suggesting that dietary lipids affect immune function.
authors.affiliation: Department of Internal Medicine III, Giessen University Hospital, Germany. Electronic address: andreas.schmid@innere.med.uni-giessen.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schmid
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Germany.
authors.forename: Margarita
authors.initials: M
authors.lastname: Bala
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Leszczak
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Germany.
authors.forename: Irene
authors.initials: I
authors.lastname: Ober
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Germany.
authors.forename: Christa
authors.initials: C
authors.lastname: Buechler
authors.affiliation: Department of Internal Medicine III, Giessen University Hospital, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Karrasch
mesh_terms: D017667:Adipocytes / Q000187:drug effects; D000293:Adolescent; D000328:Adult; D000818:Animals; D002460:Cell Line; D018932:Chemokine CCL2 / Q000037:antagonists & inhibitors / Q000097:blood*; D018946:Chemokine CCL5 / Q000097:blood*; D054357:Chemokine CXCL10 / Q000097:blood*; D018925:Chemokines / Q000097:blood*; D015331:Cohort Studies; D004041:Dietary Fats / Q000008:administration & dosage*; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D015228:Hypertriglyceridemia / Q000276:immunology; D007249:Inflammation / Q000209:etiology / Q000276:immunology; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D019787:Linoleic Acid / Q000494:pharmacology; D008297:Male; D051379:Mice; D008875:Middle Aged; D019301:Oleic Acid / Q000494:pharmacology; D012727:Sex Characteristics; D014280:Triglycerides / Q000008:administration & dosage*; D055815:Young Adult
chemical_list: C111835:CCL2 protein, human; C483024:CCL5 protein, human; C114753:CXCL10 protein, human; D018932:Chemokine CCL2; D018946:Chemokine CCL5; D054357:Chemokine CXCL10; D018925:Chemokines; D004041:Dietary Fats; D005230:Fatty Acids, Nonesterified; D036341:Intercellular Signaling Peptides and Proteins; C478630:RARRES2 protein, human; D014280:Triglycerides; D019301:Oleic Acid; D019787:Linoleic Acid
keywords: CCL2; Chemerin; Chemokine; Hypertriglyceridemia; IP-10; Inflammation; Oral lipid tolerance test; RANTES