Anti‐obesity Effects of Ecklonia stolonifera Extract in 3T3‐L1 Cells

Obesity is caused by excessive fat accumulation when energy intake exceeds energy expenditure. Recent studies have shown that dietary phytochemicals can suppress adipogenesis and promote lipolysis. Ecklonia stolonifera , which belongs to the family Laminariaceae, is a perennial brown marine alga that is rich in phlorotannins. Many studies have been reported that Ecklonia stolonifera has antioxidative, hepatoprotective, and anti‐inflammatory activities. However, it is not known yet whether Ecklonia stolonifera has an anti‐obesity property and improves lipid metabolism. In our study, the anti‐obesity effects of Ecklonia stolonifera Extract (ESE) were investigated in 3T3‐L1 cells. ESE reduced the expression levels of adipogenesis‐related genes such as CCAAT/enhancer‐binding protein alpha (C/EBPα) and fatty acid‐binding protein 4 (FABP4). In addition, ESE reduced the expression levels of lipogenesis‐related genes such as lysophosphatidic acid acyltransferase theta (LPAATθ), diacylglycerol acyltransferase 1 (DGAT1) and sterol regulatory element‐binding protein 1 (SREBP1). Moreover, ESE increased the expression of adipose triglyceride lipase (ATGL) and hormone‐sensitive lipase (HSL), which are related to lipolysis pathway. Lastly, ESE promoted lipolysis via protein kinase A (PKA) mediated pathway. In conclusion, ESE modulates adipocyte differentiation and lipid metabolism by reducing lipogenesis and stimulating lipolysis. These results suggest that ESE may have therapeutic implications for the development of new anti‐obesity agent.