Mechanism of gambogenic acid in resisting angiogenesis of lung cancer in vitro / 中国中药杂志

The aim of this paper was to observe the effect of gambogenic acid on angiogenesis of lung cancer and its preliminary mechanism. After culturing lung adenocarcinoma A549 cells, the conditioned medium was treated with gambogenic acid and then used to culture human umbilical vein endothelial cells (HUVECs) to establish the indirect contact cell co-culture system. A two-dimensional culture model of HUVEC was established with matrigel to observe the effect of gambogenic acid on angiogenesis. DAPI staining was used to observe the morphological changes in HUVEC cells after treatment with gambogenic acid under the fluorescence microscope. Annexin V-FITC/PI staining and flow cytometry analysis were used to determine gambogenic acid's effect on HUVEC cell apoptosis rate. The protein expressions of PI3K, p-PI3K, Akt, p-Akt were measured by Western blot. PTEN-siRNA was transfected into cells, and RT-PCR was used to detect the expression levels of PI3K and Akt genes. Gambogenic acid can significantly inhibit angiogenesis, and its inhibitory effect was dose-dependent. DAPI staining showed apoptotic morphological features of HUVEC cells under fluorescence microscope. Annexin V-FITC/PI staining showed that gambogenic acid induced apoptosis in HUVECs. The results of Western blot showed that the expressions of p-PI3K and p-Akt protein were down-regulated with gambogenic acid, while the expressions of PI3K and Akt protein was insignificant. The results of RT-PCR indicated that the expressions of PI3K and Akt protein were up-regulated by PTEN siRNA. Gambogenic acid can inhibit angiogenesis in lung cancer in vitro, and the mechanism of inhibiting angiogenesis may be related to the PI3K/Akt signaling pathway.

Inhibiting effects of gambogenic acid in combination withmiR-218 on cervival cancer HeLa cells and its mechanisms / 中国药理学通报

Aim To study the inhibitory effects of gambogenic acid in combination with miR-218 on cervical cancer HeLa cells and its mechanisms.Methods Eukaryotic expression vector of miR-218(pmi8-218) was transfected into HeLa cells.Transcript levels of miR-218 were quantified by real-time quantitative PCR.HeLa cells were incubated with different concentrations of gambogenic acid alone or in combination with pmiR-218.The cell growth inhibiting ratio of HeLa cells was assessed by MTT assay.Cell apoptosis was measured by fluorescence activated cell sorting.The expression levels of Bcl-2, Bax and E-cadherin were measured by Western blot and qRT-PCR.Results Levels of miR-218 transcript significantly increased in pmiR-218 transfected HeLa cells.Overexpression of miR-218 may enhance the sensitivity of HeLa cells to gambogenic acid.Over expression of miR-218 could enhance the effect of gambogenic acid on inhibition cell proliferation, promoting apoptosis of HeLa cells.pmiR-218 could enhance the regulation of Bax expression and decrease the expression of Bcl-2 in HeLa cells.Conclusions Over expression of miR-218 may enhance the sensitivity of HeLa cells to gambogenic acid;miR-218 can enhance the effect of gambogenic acid on inhibition cell proliferation and promote the apoptosis of HeLa cells, and the mechanism may be related to down-regulation of Bcl-2/Bax expression.

Effects of gambogenic acid on proliferation and apoptosis of A 549 lung cancer cells / 国际检验医学杂志

Objective To investigate the effects of gambogenic acid(GNA) on the proliferation and apoptosis of A549 lung canc‐er cells and its possible mechanism of regulation .Methods A549 cells were treated with different concentrations of GNA ,which di‐vided into control group and GNA group(0 .5 ,1 .5 ,20 mg/L) .The cell proliferation and apoptosis of A549 was analyzed by MTT , Hoechst staining ;The expression of apoptosis‐related protein caspase3 ,caspase9 ,p53 and NF‐κB were studied by Western blot .Re‐sults GNA could inhibit growth of A549 cells ;Moreover GNA could also induce apoptosis with the concentration increased more obviously ;Western blot showed that GNA down‐regulate NF‐κB ,increased caspase3 ,caspase9 and p53 expression(P<0 .05) .Con‐clusion GNA can efficiently promote the cell proliferation inhibition and the apoptosis of A 549 cells .

Preparation of gambogenic acid loaded nanostructured lipid carriers and its pharmaceutical properties / 中草药

Objective: To prepare and characterize gambogenic acid loaded nanostuctured lipid carrier (GNA-NLC). Methods: GNA-NLC was prepared by emulsion evaporation-low temperature solidification method, and its optimal prescription was selected by orthogonal test design. The characteristics, such as encapsulation efficiency (EE), average diameter, and Zeta potential, were studied. Results: GNA-NLC had a spherical shape with smooth surface with the average diameter of (144.07 ± 1.44) nm, polydispersity index (PI) of 0.24 ± 0.01, Zeta potential of (-28.03 ± 0.29) mV. The EE and drug loading were (84.65 ± 0.98)% and (4.21 ± 0.05)%, respectively. DSC indicated that GNA was dispersed as non-crystalline in matrix. Conclusion: Emulsion evaporation-low temperature solidification method is easy, simple, and feasible to prepare GNA-NLC.

Preparation and process optimization of gambogenic acid inclusion complex of freeze-dried powder injection / 中草药

Objective To optimize the preparation of gambogenic acid hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex of freeze-dried powder injection. Methods Gambogenic acid HP-β-CD inclusion complex of freeze-dried powder injection was prepared by freeze-drying method, gambogenic acid content was determined by HPLC, and the preparation was optimized by orthogonal design taking inclusion rate as index. Results The optimized preparation process for inclusion was that the reaction mass charge ratio (HP-β-CD-gambogenic acid) was 10 : 1, for 5 h at 20°C. The inclusion rate of prepared inclusion complex was higher; The freeze-dried powder was with color uniformity, fluffy texture, and good solubility. Conclusion The process is reasonable and with good reproducibility.

Study on the mechanism of gambogenic acid-induced apoptosis of human colon cancer HCT116 cells / 肿瘤

Objective: To investigate the pro-apoptotic effect of gambogenic acid (GNA) on human colonic carcinoma HCT116 cells, and to explore the possible molecular mechanism. Methods: MTT assay was performed to detect proliferation inhibition effect of GNA on HCT116 cells. After staining with DAPI, the pro-apoptotic effect of GNA on HCT116 cells was observed under a fluorescence microscope. The changes in cell cycle distribution of HCT116 cells induced by GNA were examined by FCM. The expressions of cyclin D1, cyclin E, P21, P27 and poly (ADP-ribose) polymerase (PARP) proteins in HCT116 cells were detected by Western blotting. Results: GNA exerted an significant inhibitory effect on HCT116 cell proliferation in a time-and dose-dependent manner, and it could induce the typical nuclear apoptotic morphology. Under a fluorescence microscope, DAPI staining results showed that GNA could obviously induce the apoptosis of HCT116 cells. FCM showed that GNA could significantly increase the percentage of cells at G0/G1 phase, whereas obviously decrease the percentage of cells at S phase, which indicated that the cell cycle was arrested at G 0/G1 phase. Western blotting analysis showed that GNA could efficiently down-regulate the expression levels of cyclin D1 and cyclin E proteins, whereas up-regulate the expression levels of P21 and P27 proteins, and also promote the cleavage of PARP. Conclusion: GNA can induce the cell cycle arrest at G0/G1 phase by down-regulating the expression levels of cyclin D1 and cyclin E, and up-regulating the expression levels of P21 and P27. Therefore, GNA can efficiently promote the cell proliferation inhibition and the apoptosis of HCT116 cells. Copyright© 2011 by TUMOR.