N-acetylcysteine inhibits kinase phosphorylation during 3T3-L1 adipocyte differentiation

ABSTRACT

Objectives: Reports investigating the effects of antioxidants on obesity have provided contradictory results. We have previously demonstrated that treatment with the antioxidant N-acetylcysteine (NAC) inhibits cellular triglyceride (Tg) accumulation as well as total cellular monoamine oxidase A (MAOA) expression in 3T3-L1 mature adipocytes (Calzadilla et al., Redox Rep. 2013;210–218). Here we analyzed the role of NAC on adipogenic differentiation pathway.

Methods: Assays were conducted using 3T3-L1 preadipocytes (undifferentiated cells: CC), which are capable of differentiating into mature adipocytes (differentiated cells: DC). We studied the effects of different doses of NAC (0.01 or 1 mM) on DC, to evaluate cellular expression of phospho-JNK½ (pJNK½), phospho-ERK½ (pERK½) and, mitochondrial expression of citrate synthase, fumarate hydratase and MAOA.

Results: Following the differentiation of preadipocytes, an increase in the expression levels of pJNK½ and pERK½ was observed, together with mitotic clonal expansion (MCE). We found that both doses of NAC decreased the expression of pJNK½ and pERK½. Consistent with these results, NAC significantly inhibited MCE and modified the expression of different mitochondrial proteins.

Discussion: Our results suggested that NAC could inhibit Tg and mitochondrial protein expression by preventing both MCE and kinase phosphorylation.

KEYWORDS:

• Antioxidant
• obesity
• 3T3-L1
• adipocyte differentiation
• MAPK
• mitocondria
• kinase phosphorylation
• monoamine oxidase A

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes on contributors

Daniela Soto is a student in Biological Science, University of Buenos Aires (2008–present). Current research: Adipocyte differentiation. Scientific articles (last 5 years): 2.

Ms Gómez-Serrano studied Biology at the University of Alcalá, Spain (2006–2011), and received her MsD degree in Molecular Biomedicine from the Autonomous University of Madrid, Spain (2012). In 2012, she moved to Instituto de Investigaciones Biomédicas ‘Alberto Sols’ (IIB) in Madrid, where she started her PhD project in Dr Peral's lab. Her major field of research concerns the application of high-throughput proteomic techniques on the study biology of human adipose tissue in relation to obesity and obesity-related complications. Scientific articles (in the last 5 years): 9.

Azul Victoria Pieralisi is a student in Biological Science, University of Buenos Aires (2011–present). Current research: Antioxidants. Scientific articles (last 5 years): 1.

Juan Carlos Calvo, PhD and full professor of Biological Chemistry, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires. Senior scientist at the Institute of Biology and Experimental Medicine (IBYME), CONICET. Current research: Human reproduction and mammary and prostate cancer.

Belen Peral, PhD and scientific researcher at the Spanish Research Council, Instituto de Investigaciones Biomédicas, Alberto Sols, Madrid. Principal researcher of eight projects. Current research: Obesity. Scientific articles: 52.

Liliana N. Guerra, PhD of Chemical Sciences, University of Buenos Aires. Professor of Pharmacology, University of Lujan. Vice-president of Argentine Cell Bank Association. Laboratory head at Facultad de Ciencias Exactas y Naturales, University of Buenos Aires. Principal researcher of nine projects. Current research: Antioxidants and obesity. Scientific articles and books (last 5 years): 7.

ORCiD

María Gomez-Serrano http://orcid.org/0000-0002-9669-091X

Juan C. Calvo http://orcid.org/0000-0001-7632-611X

Additional information

Funding

This study was supported by the grant UBACYT 20020130200160BA (Universidad de Buenos Aires, Argentina), OAT N°42/2013 (Universidad de Buenos Aires, Argentina) and, the grant SAF-2009-10461 (Ministerio de Ciencia e Innovación Tecnológica, España). Juan Carlos Calvo and Liliana N. Guerra are researchers funded by CONICET (Ministerio de Ciencia y Técnica, Argentina) and Universidad de Buenos Aires.