Sinapic acid prevents adipogenesis by regulating transcription factors and exerts an anti-ROS effect by modifying the intracellular anti-oxidant system in 3T3-L1 adipocytes

In this study, we tested the hypothesis that sinapic acid (SA), a naturally occurring hydroxycinnamic acid found in vegetables, cereal grains, and oilseed crops with various biological activities suppresses adipogenesis in 3T3-L1 adipocytes by down-regulating adipogenesis transcription factor. 

3T3-L1 adipocytes were treated with SA and evaluated by Oil Red O staining, triglyceride estimation, lipolysis, and reverse transcription-polymerase chain reaction. 3T3-L1 adipocytes were treated with various concentrations of SA (100 to 1000 μmol) during differentiation. 

SA prevented an increase in adipocytes by reducing preadipocyte clonal expansion. ORO staining analyses revealed that SA reduced cytoplasmic lipid droplet accumulation in 3T3-L1 by 57% at the highest concentration of 1000 μmol without affecting cell viability. Furthermore, SA down-regulated the expression of peroxisome proliferator-activated receptor-gamma, CCAAT/enhancer-binding protein alpha, sterol regulatory element-binding protein 1c, and fatty acid synthase. ROS generated during adipogenesis was also attenuated by SA treatment by increasing antioxidant enzymes superoxide dismutase, catalase, and the cellular antioxidant glutathione. SA demonstrated no in vivo toxicity in the Drosophila melanogaster model. 

These results suggest that SA exerts anti-oxidant and anti-adipogenic effects and could be used as a functional nutraceutical ingredient in combatting obesity-related diseases.