Acacetin, a
flavone that can be isolated from the Saussurea involucrata plant, has anti-
tumor and anti-inflammatory properties that ameliorate
airway hyperresponsiveness in asthmatic mice. This study investigated whether
acacetin has anti-adipogenic effects in 3T3-L1 adipocytes and whether it regulates the inflammatory response in adipocytes and macrophages. It also investigated whether
acacetin ameliorates
lipid accumulation in high-fat diet- (HFD) induced obese mice. Differentiated 3T3-L1 cells were treated with
acacetin. The
glycerol levels in the culture medium were measured, and the expression of
proteins and genes involved in adipogenesis and lipolysis were assayed by Western blot and real-time PCR, respectively. Inflammatory
cytokine signaling pathway activity was assessed in macrophages that were treated with
acacetin and cultured with differentiated medium from 3T3-L1 cells.
Intraperitoneal injections of
acacetin were administered to HFD-induced obese mice twice a week for 10 weeks.
Acacetin significantly increased the levels of
glycerol in the culture medium and significantly inhibited
lipid accumulation in adipocytes.
Acacetin reduced the expression of adipogenesis-related
transcription factors, including the expression of the
CCAAT/enhancer-binding protein; it also increased
sirtuin 1 expression and AMPK phosphorylation in adipocytes. In macrophages cultured with differentiated media from 3T3-L1 adipocytes,
acacetin reduced the levels of inflammatory mediators and the activity of the
mitogen-activated protein kinase and NF-κB pathways. In obese mice,
acacetin reduced both
body weight and visceral adipose tissue weight. These results demonstrate that
acacetin inhibited adipogenesis in adipocytes and in obese mice.
Acacetin also reduced the inflammatory response of macrophages that were stimulated with differentiated media from 3T3-L1 cells.