TY - JOUR
T1 - Mild mitochondrial uncoupling induces 3T3-L1 adipocyte de-differenciation by a PPAEγ-independent mechanism, whereas TNFα-induced de-differentiation is PPARγ dependent
AU - Tejerina Vargas, Silvia Veronica
AU - De Pauw, Aurélia
AU - Vankoningsloo, Sebastien
AU - Houbion, Andrée
AU - Renard, Patricia
AU - De Longueville, Françoise
AU - Raes, Martine
AU - Arnould, Thierry
N1 - Publication code : RES. ACAD.
PY - 2009
Y1 - 2009
N2 - Impairment of mitochondrial activity affects lipid-metabolizing tissues and mild mitochondrial uncoupling has been proposed as a possible strategy to fight obesity and associated diseases. In this report, we characterized the 3T3-L1-adipocyte 'de-differentiation' induced by carbonyl cyanide (p-trifluoromethoxy)-phenylhydrazone (FCCP), a mitochondrial uncoupler. We found a decrease in triglyceride (TG) content in adipocytes incubated with this molecule. We next analyzed the expression of genes encoding adipogenic markers and effectors and compared the differentially expressed genes in adipocytes treated with FCCP or TNF{alpha} (a cytokine known to induce adipocyte de-differentiation). Furthermore, a significant decrease in the transcriptional activity of PPAR{gamma} and C/EBP{alpha} transcription factors was found in adipocytes with impaired mitochondrial activity. However, although these modifications were also found in TNF{alpha}-treated adipocytes, rosiglitazone and 9-cis retinoic acid (PPAR{gamma} and RXR ligands) were unable to prevent triglyceride loss in FCCP-treated cells. Metabolic assays also revealed that TG reduction could be mediated by a downregulation of lipid synthesis rather than an upregulation of fatty acid oxidation. Finally, lipolysis stimulated by the uncoupler also seems to contribute to the TG reduction, a process associated with perilipin A downregulation. These results highlight some new mechanisms that might potentially be involved in adipocyte de-differentiation initiated by a mitochondrial uncoupling.
AB - Impairment of mitochondrial activity affects lipid-metabolizing tissues and mild mitochondrial uncoupling has been proposed as a possible strategy to fight obesity and associated diseases. In this report, we characterized the 3T3-L1-adipocyte 'de-differentiation' induced by carbonyl cyanide (p-trifluoromethoxy)-phenylhydrazone (FCCP), a mitochondrial uncoupler. We found a decrease in triglyceride (TG) content in adipocytes incubated with this molecule. We next analyzed the expression of genes encoding adipogenic markers and effectors and compared the differentially expressed genes in adipocytes treated with FCCP or TNF{alpha} (a cytokine known to induce adipocyte de-differentiation). Furthermore, a significant decrease in the transcriptional activity of PPAR{gamma} and C/EBP{alpha} transcription factors was found in adipocytes with impaired mitochondrial activity. However, although these modifications were also found in TNF{alpha}-treated adipocytes, rosiglitazone and 9-cis retinoic acid (PPAR{gamma} and RXR ligands) were unable to prevent triglyceride loss in FCCP-treated cells. Metabolic assays also revealed that TG reduction could be mediated by a downregulation of lipid synthesis rather than an upregulation of fatty acid oxidation. Finally, lipolysis stimulated by the uncoupler also seems to contribute to the TG reduction, a process associated with perilipin A downregulation. These results highlight some new mechanisms that might potentially be involved in adipocyte de-differentiation initiated by a mitochondrial uncoupling.
KW - Adipocyte de-diffenciation
KW - Mitochondrial dysfunction
KW - Gene expression
UR - http://www.scopus.com/inward/record.url?scp=62149139816&partnerID=8YFLogxK
M3 - Article
SN - 1477-9137
VL - 122
SP - 145
EP - 155
JO - Journal of Cell Science
JF - Journal of Cell Science
ER -