title: LPS response pattern of inflammatory adipokines in an in vitro 3T3-L1 murine adipocyte model.
abstract: OBJECTIVE
  In vitro 3T3-L1 mouse cells represent a reliable model to investigate the inflammatory phenotype of adipocytes activated by bacteria-derived lipopolysaccharide (LPS). In this study we have evaluated the differential expression of adipokines in response to increasing doses of LPS and various incubation times.
  
  
  METHODS
  3T3-L1 mouse adipocytes were treated with E. coli LPS (from 0 to 10 μg/ml) for a time course ranging from 4 to 24 h, 4 h each. A time point at 2 h was also included to highlight early activation by LPS. mRNA expression by RT-PCR on cell lysates and ELISA assays on cell culture supernatants were performed.
  
  
  RESULTS
  Cells activated by increasing doses of LPS upregulated TNF-α expression in the first 2 h, but this expression slowed down within 6-8 h, while IL-6 expression was increasing. This reduction was also observed for CXCL12/SDF1α. Unlike IL-10, IL-6 expression was constantly upregulated by prolonging incubation with LPS. TNF-α and CXCL12 gene expression occurred early in the time-course and exhibited a second increase following the first 4-6 h of incubation with LPS. Optimal expression of most adipokines needed 6-8 h of a prolonged treatment with LPS at 37 °C. The chemokines MIP-1α/CCL3 and MIP-1β/CCL4 were maximally expressed within the first 8 h, then significantly reduced in the following times. IL-10 expression was upregulated by low doses of LPS and downregulated by prolonging time with the bacterial endotoxin. ELISA analysis of released products generally confirmed the result from gene expression experiments.
  
  
  CONCLUSIONS
  These data, while assessing previously reported results, highlighted new evidence about the time-dependency in LPS-mediated adipokine production, thus contributing to the comprehension of the inflammatory response of adipocyte.
authors: Unit of Geriatry, Department of Medicine, University of Verona, Verona, Italy, salvatore.chirumbolo@univr.it.
authors: Salvatore
authors: S
authors: Chirumbolo
authors: Guido
authors: G
authors: Franceschetti
authors: Elena
authors: E
authors: Zoico
authors: Clara
authors: C
authors: Bambace
authors: Luciano
authors: L
authors: Cominacini
authors: Mauro
authors: M
authors: Zamboni
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000187:drug effects* / Q000276:immunology; D054392:Adipokines; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000235:genetics / Q000276:immunology*; D015870:Gene Expression / Q000187:drug effects; D008070:Lipopolysaccharides / Q000494:pharmacology*; D051379:Mice
chemical_list: D054392:Adipokines; D016207:Cytokines; D008070:Lipopolysaccharides