Compounds that inhibit triglyceride accumulation and TNFα secretion in adipocytes

Naofumi Shiomi, Miwako Maeda, Minori Mimura
DOI: 10.4236/jbise.2011.411085                

Abstract

Obese subjects show both a fatty predisposition and a higher risk of metabolic syndrome. This characteristic depends on adipocytes. However, the roles of adipocytes in metabolic syndrome have been insufficiently investigated, because few pure adipocyte cell lines have been isolated. The present study had two objectives: the isolation of a pure adipocyte cell line and clarification of the differences between adipocytes and preadipocytes, and screening for compounds that can potentially prevent metabolic syndrome. We isolated a novel adipocyte cell line, 3T3-L24. In the 3T3-L24 cells, the gene expression levels (of C/EBPα and β, PPARγ and AP2) and the production of triglyceride and TNFα were much higher than those in the preadipocyte 3T3-L1 cells. We used the 3T3-L24 adipocytes to screen for compounds that could inhibit triglyceride accumulation and TNFα secretion. Fatty acids enhanced the triglyceride accumulation. Sodium carboxylate, taurine and carnitine not only inhibited triglyceride accumulation, but also inhibited TNFα secretion. Therefore, these compounds might be effective to decrease the risk of metabolic syndrome in obese subjects.

Keywords

Adipocyte; Metabolic Syndrome; Triglyceride; TNFα; Fatty Acid; Carboxylate; Taurine; Carnitine

Conflicts of Interest

The authors declare no conflicts of interest.

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