title: Free fatty acids and IL-6 induce adipocyte galectin-3 which is increased in white and brown adipose tissues of obese mice.
abstract: Galectin-3 regulates immune cell function and clearance of advanced glycation end products. Galectin-3 is increased in serum of obese humans and mice and most studies suggest that this protein protects from inflammation in metabolic diseases. Current data show that galectin-3 is markedly elevated in the liver, subcutaneous and intra-abdominal fat depots of mice fed a high fat diet and ob/ob mice. Galectin-3 is also increased in brown adipose tissues of these animals and immunohistochemistry confirms higher levels in adipocytes. Raised galectin-3 in obese white adipocytes has been described in the literature and regulation of adipocyte galectin-3 by metabolites with a role in obesity has been analyzed. Galectin-3 is expressed in 3T3-L1 fibroblasts and human preadipocytes and is modestly induced in mature adipocytes. In 3T3-L1 adipocytes galectin-3 is localized in the cytoplasm and is also detected in cell supernatants. Glucose does not alter soluble galectin-3. Lipopolysaccharide has no effect while TNF reduces and IL-6 raises this lectin in cell supernatants. Palmitate and oleate modestly elevate soluble galectin-3. Differentiation of 3T3-L1 cells in the presence of 100 μM and 200 μM linoleate induces soluble galectin-3 and cellular levels are upregulated by the higher concentration. Current data suggest that free fatty acids and IL-6 increase galectin-3 in adipocytes and thereby may contribute to higher levels in obesity.
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Krautbauer
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Eisinger
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Hader
authors.affiliation: Department of Internal Medicine I, Regensburg University Hospital, Regensburg, Germany. Electronic address: christa.buechler@klinik.uni-regensburg.de.
authors.forename: Christa
authors.initials: C
authors.lastname: Buechler
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000378:metabolism*; D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000378:metabolism*; D052436:Adipose Tissue, White / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D005230:Fatty Acids, Nonesterified / Q000494:pharmacology*; D005234:Fatty Liver / Q000378:metabolism / Q000473:pathology; D037502:Galectin 3 / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D007249:Inflammation / Q000473:pathology; D015850:Interleukin-6 / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D005230:Fatty Acids, Nonesterified; D037502:Galectin 3; D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D005947:Glucose
keywords: Brown fat; Free fatty acid; Lipopolysaccharide; Obesity