Gambogic Acid Induced Apoptosis through Activation of Caspase-dependent Pathway in Aortic Smooth Muscle Cells

Autor: Eun Ae Kim, Tae-Jin Lee, Dae Kwang Kim, Joo-Young Kim, Kyung Gon Kim, Ju Hwan Kang
Rok vydání: 2013
Předmět:
Zdroj: Korean Journal of Physical Anthropology. 26:105
ISSN: 2287-626X
1225-150X
DOI: 10.11637/kjpa.2013.26.3.105
Popis: Gambogic acid (GA) has powerful apoptotic actions. The authors investigated whether GA has apoptotic effects on aortic smooth muscle cells, and compared its potency with that of simvastatin. Smooth muscle cells were isolated from the aortas of Sprague-Dawley rats (4-6 week). Cell purities were confirmed by IF staining using α-smooth muscle actin antibody. The IC 50 values for cell death by GA and simvastatin were determined using a MTT assay, and the apoptotic effects of 1 μM GA or 30 μM simvastatin (concentrations correspond to IC 50 values) were determined after 24 h of treatment using live cell images and by FITC annexin-V and propidium iodide double-staining. In addition, western blotting was used to evaluate apoptosis by quantifying reductions in the expression levels of the PARP and procaspase-3 as well as cleavages of PARP and procaspase-3 after treatment with 1 μM GA or 30 μM simvastatin. The IC 50 of GA (1 μM) was lower than that of simvastatin (30 μM). Cell numbers were markedly reduced by both drugs in live cell images. GA (1 μM) produced a higher level of apoptosis than 30 μM simvastatin (26.4±2.37% vs. 8.3±1.54%, respectively; P?0.05, n=3) by FITC annexin-V & PI double-staining. In addition, 1 μM GA reduced the expressions of PARP, procaspase-3, and Mcl-1 in cells, whereas 30 μM simvastatin did not. Pretreatment with z-VAD-fmk attenuated GA-induced apoptosis and the cleavages of PARP and procaspase-3. The decreased level of Mcl-1 protein induced by GA treatment was recovered by z-VAD-fmk. These results indicate that GA-induced apoptosis was mediated by a caspase-dependent pathway.
Databáze: OpenAIRE