RESUMO
The long-term objective of the present study was to prepare, physicochemically characterize and determine the anticancer of clausenidin/hydroxypropyl-ß-cyclodextrin (Clu/HPßCD) inclusion complex. We used differential scanning calorimetry, X-ray diffractometer, fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometer and 13C and 1H nuclear magnetic resonance followed by in vitro anticancer assays. The orientation and intermolecular interactions of Clausenidin within cyclodextrin cavity were also ascertained by molecular docking simulation accomplished by AutoDock Vina. The guest molecule was welcomed by the hydrophobic cavity of the host molecule and sustained by hydrogen bond between host/guest molecules. The constant drug release with time, and increased solubility were found after successful complexation with HPßCD as confirmed by physicochemical characterizations. Clausenidin had greater cytotoxic effect on colon cancer HT29 cells when incorporated into HPßCD cavity than dissolved in DMSO. Also, from a comparison of cell viability between normal and cancer cells, a reduced side effect was observed. The Clu/HPßCD inclusion complex triggered reactive oxygen species-mediated cytotoxicity in HT29 cells. The inclusion complex-treated HT29 cells showed cell cycle arrest and death by apoptosis associated with caspases activation. The presence of HPßCD seems to aid the anticancer activity of clausenidin.
RESUMO
BACKGROUND: Clausena excavata Burm.f. is a shrub traditionally used to treat cancer patients in Asia. The main bioactive chemical components of the plant are alkaloids and coumarins. In this study, we isolated clausenidin from the roots of C. excavata to determine its apoptotic effect on the colon cancer (HT-29) cell line. METHOD: We examined the effect of clausenidin on cell viability, ROS generation, DNA fragmentation, mitochondrial membrane potential in HT-29 cells. Ultrastructural analysis was conducted for morphological evidence of apoptosis in the treated HT-29 cells. In addition, we also evaluated the effect of clausenidin treatment on the expression of caspase 3 and 9 genes and proteins in HT-29 cells. RESULT: Clausenidin induced a G0/G1 cell cycle arrest in HT-29 cells with significant (p < 0.05) dose-dependent increase in apoptotic cell population. The DNA fragmentation assay also showed apoptotic features in the clausenidin-treated HT-29 cells. Clausenidin treatment had caused significant (p < 0.05) increases in the expression of caspase 9 protein and gene in HT-29 cells and mitochondrial ROS and mitochondrial membrane depolarization. The results suggest the involvement of the mitochondria in the caspase-dependent apoptosis in clausenidin-treated colon cancer cells. CONCLUSION: Clausenidin induces a caspase-dependent apoptosis in colon cancers through the stimulation of the mitochondria. The study demonstrates the potential of clausenidin for use in the treatment of colon cancers.
Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Clausena/química , Neoplasias do Colo/metabolismo , Extratos Vegetais/farmacologia , Piranocumarinas/farmacologia , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Extratos Vegetais/química , Piranocumarinas/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
Clausena excavata Burm f. is used by traditional healers to treat cancer patients in South East Asia. The use of the plant and its compounds is based on Asian folklore with little or no scientific evidence supporting the therapeutic efficacy The current study aimed to determine the effect of pure clausenidin isolated from C. excavata on caspase-8-induced cell death as well as angiogenesis in the HepG2 hepatocellular carcinoma cell line. Caspase-8 and extrinsic death receptor protein expression was determined using spectrophotometry and protein profile arrays, respectively. Ultrastructural analysis of clausenidin-treated cells was conducted using transmission electron microscopy. In addition, anti-angiogenic effects of clausenidin were investigated by Western blot analysis. Clausenidin significantly (p<0.05) increased the activity of caspase-8 and expression of protein components of the death inducing signaling complex (DISC) in HepG2 cells. Ultrastructural analysis of the clausenidin-treated HepG2 cells revealed morphological abnormalities typical of apoptosis. Furthermore, clausenidin significantly (p<0.05) decreased the expression of vascular endothelial growth factor (VEGF). Therefore, clausenidin is a potential anti-angiogenic agent which may induce apoptosis of hepatocellular carcinoma cells.
Assuntos
Apoptose/efeitos dos fármacos , Carbazóis/farmacologia , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Clausena/química , Extratos Vegetais/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Proliferação de Células/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais CultivadasRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Clausena excavata Burm.f. is used locally in folk medicine for the treatment of cancer in South East Asia. AIM OF THE STUDY: To determine the mechanism of action of pure clausenidin crystals in the induction of hepatocellular carcinoma (hepG2) cells apoptosis. MATERIALS AND METHODS: Pure clausenidin was isolated from Clausena excavata Burm.f. and characterized using 1H and 13C NMR spectra. Clausenidin-induced cytotoxicity was determined by MTT assay. The morphology of hepG2 after treatment with clausenidin was determined by fluorescence and Scanning Electron Microscopy. The effect of clausenidin on the apoptotic genes and proteins were determined by real-time qPCR and protein array profiling, respectively. The involvement of the mitochondria in clausenidin-induced apoptosis was investigated using MMP, caspase 3 and 9 assays. RESULTS: Clausenidin induced significant (p<0.05) and dose-dependent apoptosis of hepG2 cells. Cell cycle assay showed that clausenidin induced a G2/M phase arrest, caused mitochondrial membrane depolarization and significantly (p<0.05) increased expression of caspases 3 and 9, which suggest the involvement of the mitochondria in the apoptotic signals. In addition, clausenidin caused decreased expression of the anti-apoptotic protein, Bcl 2 and increased expression of the pro-apoptotic protein, Bax. This finding was confirmed by the downregulation of Bcl-2 gene and upregulation of the Bax gene in the treated hepG2 cells. CONCLUSION: Clausenidin extracted from Clausena excavata Burm.f. is an anti-hepG2 cell compound as shown by its ability to induce apoptosis through the mitochondrial pathway of apoptosis. Clausenidin can potentially be developed into an anticancer compound.