Table 1.
Sequences of the primers used in real-time PCR.
Figure 1.
The ethanol extract of kuding tea inhibits 3T3-L1 adipocyte differentiation.
The water extract and the ethanol extract were added into the medium at the concentration of 20 µg/ml. DMSO was used as the vehicle control. The cells were stained with oil red O at day 6 of differentiation. GM: growth medium; DM: differentiation medium.
Figure 2.
EK inhibits 3T3-L1 adipocyte differentiation induced by DM.
(A): EK was used at the beginning of DM induction of 3T3-L1 cells and was removed during differentiation. (B): EK was only used during the differentiation of 3T3-L1 cells. The cells were stained with oil red O at day 6 of differentiation. (C): Real-time RT-PCR results of gene expression levels in 3T3-L1 adipocyte. The cell was differentiated for 6 days and then the cell was treated with EK at 20 µg/ml for 24 hours. DM: differentiation medium. β-actin was used as an internal control. Data are presented as means ± SE for 4 treatments. *P<0.05.
Figure 3.
EK ameliorates metabolic disorders in high-fat diet-induced obesity C57BL/6 mice.
(A): Body weight gain. (B): Food intake amount. (C): Fecal TG contents. (D): Images of white and brown adipocytes under a scanning electron microscope. (E): Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c) levels. (F): Effects of EK on glucose tolerance in HFD fed mice as determined by the glucose tolerance test (GTT). NS: No significance. The data were shown as mean ± SE. N = 7 for all groups. * P<0.05.
Figure 4.
EK improves lipid accumulation in the liver of high-fat diet-induced C57BL/6 mice.
(A-C): H&E staining (×200) of livers from the standard diet (A), HF diet (B) and HF+EK mice (C). (D-F): Oil red O staining (×400) of the liver sections from the standard diet (D), HF diet (E) and HF+EK mice (F). The sections were counterstained with hematoxylin. The quantitative results of TG (G) and TC (H) content in livers are shown. The mice were fed with a high-fat diet for 5 weeks and EK was powdered and mixed into the diet at 0.05% (wt/wt). The data were presented as mean ± SE. N = 7 for all groups. * P<0.05.
Figure 5.
EK improves metabolic disorders in obese C57BL/6 mice.
(A): Body weights before and after treatment. (B): Food intake amount. (C): Images of white adipocytes using scanning electron microscopy. (D): Serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c) levels. (E): Glucose tolerance in HFD fed mice as determined by glucose tolerance test (GTT). The mice were injected glucose at 1 mg/kg for the intra-peritoneal glucose tolerance test, and glucose levels were tested at regular intervals of 15, 30, 60, and 90 minutes. NS: No significance. The data were shown as mean ± SE. N = 7 for all groups. * P<0.05.
Figure 6.
EK inhibits the expression of lipogenic genes in the mouse liver.
3T3-L1 adipocyte differentiation induced by DM. Real-time RT-PCR results of gene expression levels of PPARγ, PPARα, PPARδ/ß, C/EBPα, C/EBPß, UCP2, ACO, ACC and aP2 in liver of EK treated mice were compared to that of HF control mice from preventive treatment. β-actin was used as an internal control. Data are presented as means ± SE for 5 mice per group. *P<0.05.
Figure 7.
EK Nuclear receptor transcription activity assay.
(A, B): LXRα and LXRβ trans-activities. The expression plasmids of pCMXGal-mouse LXRα and LXRβ-LBD were co-transfected with Gal4 reporter vector MH100 × 4-TK-Luc to 293T cell for 24 hours. Then the cell was treated with 10 µM of LXR agonist GW3965 and/or 5–20 µg/ml of EK for another 24 hours. DMSO was used as the vehicle control. The relative luciferase activities were measured by comparison to rellina luciferase activities. The results represent at least three independent experiments and data are presented as means ± SE. *P<0.05. (C) Gene expression levels of LXR target genes in livers of EK treated mice were compared to that of HF control mice from preventive treatment, and β-actin was used as an internal control. Data are presented as means ± SE for 5 mice per group. *P<0.05.