Tributyltin and triphenyltin exposure promotes in vitro adipogenic differentiation but alters the adipocyte phenotype in rainbow trout

Aquat Toxicol. 2017 Jul:188:148-158. doi: 10.1016/j.aquatox.2017.05.001. Epub 2017 May 8.

Abstract

Numerous environmental pollutants have been identified as potential obesogenic compounds affecting endocrine signaling and lipid homeostasis. Among them, well-known organotins such as tributyltin (TBT) and triphenyltin (TPT), can be found in significant concentrations in aquatic environments. The aim of the present study was to investigate in vitro the effects of TBT and TPT on the development and lipid metabolism of rainbow trout (Onchorynchus mykiss) primary cultured adipocytes. Results showed that TBT and TPT induced lipid accumulation and slightly enhanced peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT enhancer binding protein alpha (C/EBPα) protein expression when compared to a control, both in the presence or absence of lipid mixture. However, the effects were higher when combined with lipid, and in the absence of it, the organotins did not cause complete mature adipocyte morphology. Regarding gene expression analyses, exposure to TBT and TPT caused an increase in fatty acid synthase (fasn) mRNA levels confirming the pro-adipogenic properties of these compounds. In addition, when added together with lipid, TBT and TPT significantly increased cebpa, tumor necrosis factor alpha (tnfa) and ATP-binding cassette transporter 1 (abca1) mRNA levels suggesting a synergistic effect. Overall, our data highlighted that TBT and TPT activate adipocyte differentiation in rainbow trout supporting an obesogenic role for these compounds, although by themselves they are not able to induce complete adipocyte development and maturation suggesting that these adipocytes might not be properly functional.

Keywords: Adipocyte culture; Fish; Obesogens; Organotins; PPARγ; TBT; TPT.

MeSH terms

  • ATP-Binding Cassette Transporters / genetics
  • Adipocytes / drug effects*
  • Adipogenesis / drug effects*
  • Animals
  • CCAAT-Enhancer-Binding Protein-alpha / metabolism
  • Lipid Metabolism / drug effects
  • Oncorhynchus mykiss / metabolism
  • Organotin Compounds / toxicity*
  • PPAR gamma / metabolism
  • Phenotype
  • Trialkyltin Compounds / toxicity*
  • Tumor Necrosis Factor-alpha / genetics
  • Water Pollutants, Chemical / toxicity*

Substances

  • ATP-Binding Cassette Transporters
  • CCAAT-Enhancer-Binding Protein-alpha
  • Organotin Compounds
  • PPAR gamma
  • Trialkyltin Compounds
  • Tumor Necrosis Factor-alpha
  • Water Pollutants, Chemical
  • tributyltin
  • triphenyltin