Fig 1.
AS extract reduces HFD-induced obesity in rats.
Rats were randomly divided into five groups: normal control, HFD model, and HFD with AS extract (100, 300, or 900 mg/kg). The extract was intragastric administered for 6 weeks. (A) Food intake per rat was recorded six times a week. (B) Food efficiency ratio was calculated as body weight gain divided by food intake. (C) Change in body weight was measured six times a week. (D) Body weight gain measured in a given week was subtracted from the weight in the previous week. Values are expressed as mean ± SE (n = 30). Significant differences were observed between normal and HFD groups. *P < 0.05, **P < 0.01, ***P < 0.001 vs. normal group; #P < 0.05, ##P < 0.01, ###P < 0.001 vs. model group.
Fig 2.
AS extract reduces adipose tissue weight, white adipocyte size and liver accumulation in obese rats.
Coefficients of (A) epididymal adipose tissue and (B) liver were calculated after rats had fasted for 12 h at the end of experiment according to the following equation: coefficient = tissue (g/rat)/weight (g/rat). (C) Epididymal adipose tissue and (D) liver were stained with hematoxylin and eosin for histopathological examination. Images were acquired at 400× magnification on a light microscopy. Values are expressed as mean ± SE (n = 6). Significant differences were observed between normal and HFD groups. *P < 0.05, **P < 0.01, ***P < 0.001 vs. normal group; #P < 0.05, ##P < 0.01, ###P < 0.001 vs. model group.
Table 1.
Effect of acetylshikonin on biochemical parameters of serum in HFD induced obese rats.
Fig 3.
AS inhibits 3T3-L1 preadipocyte differentiation and fat accumulation.
(A) Cell viability was assessed with the MTT assay24 h after AS treatment. (B) Relative lipid content. (C) Inhibition of fat droplet formation by AS. 3T3-L1 cells were seeded and induced to differentiate for 8 days with or without AS in 6-well plates, then stained with Oil Red O and imaged by light microscopy (200×). Values are expressed as mean ± SEM. Significant differences were observed between the untreated and differentiated control cells. *P < 0.05, **P < 0.01, **P < 0.001 vs. AS-treated cells; #P < 0.05, ##P < 0.01, ###P < 0.001 vs. differentiated control cells.
Fig 4.
AS inhibits PPARγ, C/EBPα, HSL, and ATGL expression in adipocytes.
Protein levels were assessed by western blotting in 3T3-L1 cells cultured for 0, 2, 4, and 7 days in the presence or absence of 1.5 μM AS during adipogenesis. Immunoblots are representative of five independent experiments; β-actin served as a loading control. *P < 0.05, **P < 0.01, ***P < 0.001 vs. untreated adipocytes at the same time point.
Fig 5.
AS induces lipolysis in mature adipocytes.
Mature 3T3-L1 cells were incubated with various concentrations of AS (0, 0.5, 1.5, and 4.5 μM) for 24 h. Values are expressed as mean amount (± SE) of glycerol released per well as a percentage of the control value. Four replicates were carried out for each treatment. Means denoted with a different letter are significantly different (P < 0.05).
Fig 6.
AS induces lipolysis in mature adipocytes by activating the phosphorylation and activity of PKA and HSL.
Fully differentiated 3T3-L1 adipocytes were incubated in the absence and presence of various concentrations of AS (0, 0.5, 1.5, and 4.5 μM) for 3 h. Immunoblots are representative of seven independent experiments; β-actin served as a loading control. *P < 0.05, **P < 0.01, ***P < 0.001 vs. untreated adipocytes at the same time point.