6-Gingerol, a Functional Polyphenol of Ginger, Promotes Browning through an AMPK-Dependent Pathway in 3T3-L1 Adipocytes

The main purpose of the present study was to investigate the browning effect of 6-gingerol (6G), one of the main functional compounds in the ethyl acetate extract of ginger (ginger ethyl acetate fraction, GEF), and its underlying mechanisms. In this study, we first discovered that GEF stimulated brown adipocyte differentiation by upregulating the expression levels of browning-specific transcription makers (UCP1, PRDM16, and PGC-1α), thereby reducing lipogenesis transcriptional regulator (C/EBPα) expression in 3T3-L1-differentiated adipocytes. Then, 6G (47.81 ± 0.62 mg/g) was identified as one of the main functional compounds in GEF using high-performance liquid chromatography. 6G promoted adipocyte browning, as evidenced by an increase in some brown/beige fat-specific genes (