The Edible red Alga, Gracilaria verrucosa, Inhibits Lipid Accumulation and ROS Production, but Improves Glucose Uptake in 3T3-L1 Cells

Gracilaria verrucosa is a red alga that is widely distributed in seaside areas of many countries. We examined the effect of G. verrucosa extract on adipogenesis, reactive oxygen species (ROS) production, and glucose uptake in 3T3-L1 cells. Oil red O staining and a nitroblue tetrazolium assay showed that G. verrucosa extract inhibited lipid accumulation and ROS production, respectively. mRNA levels of adipogenic transcription factors, peroxisome proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha, as well as of their target gene, adipocyte protein 2, were reduced upon treatment with G. verrucosa extract. However, G. verrucosa extract increased glucose uptake, glucose transporter-4 expression, and AMP-activated protein kinase (AMPK) phosphorylation compared to the control. Our results suggest that the anti-adipogenic and insulin-sensitive effects of G. verrucosa extract can be recapitulated to activation of AMPK. Copyright (c) 2012 John Wiley & Sons, Ltd.