RESUMO
INTRODUCTION: Cancer is a major issue in medical science with increasing death cases every year worldwide. Therefore, searching for alternatives and nonorthodox methods of treatments with high efficiency, selectivity and less toxicity is the main goal in fighting cancer. Acetyl-11-keto-ß-boswellic acid (AKBA), is a derivative pentacyclic triterpenoid that exhibited various biological activities with potential anti-tumoral agents. In this research, AKBA was utilized to examine the potential cytotoxic activity against MCF-7 cells in vitro and monitor the cellular and morphological changes with a prospective impact on apoptosis induction. METHODS: The cytotoxic activity of AKBA was measured by 3(4,5dimethylthiazole- 2-yl)-2,5 diphyneltetrazolium bromide (MTT) assay. A dose-dependent inhibition in MCF-7 cell viability was detected. The clonogenicity of MCF-7 cells was significantly suppressed by AKBA increment in comparison with untreated cells. RESULT: Morphologically, exposure of MCF-7 cells to high AKBA concentrations caused changes in cell nuclear morphology which was indicated by increasing in nuclear size and cell permeability intensity. The mitochondrial membrane potential (ΔΨm) was reduced by increasing AKBA concentration with a significant release of cytochrome c. Acridine orange/ethidium bromide dual staining experiment confirmed that MCF-7 cells treated with AKBA (IC50 concentration) displayed a late stage of apoptosis indicated by intense and bright reddish colour. CONCLUSION: A significant increase in reactive oxygen species formation was observed. Caspase 8 and caspase 9 activities were estimated and AKBA activated the production of caspase 8 and caspase 9 in a dose-dependent pattern. Finally, the cell phase distribution analysis was conducted, and flow cytometric analysis showed that AKBA at 200 µg mL-1 significantly arrest MCF-7 cells at the G1 phase and triggered apoptosis.
RESUMO
Lantana camara is an important medicinal plant that contains many active compounds, including pentacyclic triterpenoids, with numerous biological activities. The present study was conducted to evaluate the anti-oxidant, anti-tumour, and cell cycle arrest properties of chemical compounds extracted from L. camara leaves. Four compounds were identified after subjecting the plant methanolic extract to LC-MS/MS analysis: lantadene A, lantadene B, icterogenin, and lantadene C. Potential antioxidant activity was examined using 2, 2-diphenyl-1-picrylhydrazyl and compared with vitamin C as a control. Lantadene A and B were confirmed to possess the highest scavenging activity, while icterogenin and lantadene C exhibited a lesser antioxidant effect. All extracted compounds exerted a dose-dependent reduction in MCF-7 cell viability; however, lantadene B showed the highest anti-cancer activity, with an IC50 of 112.2 µg mL-1, and was therefore used in subsequent experiments. The results also confirmed the significant release of caspase 9 in a dose-dependent pattern following treatment of MCF-7 cells with a range of lantadene B concentrations. Lantadene B was found to induce MCF-7 cell cycle arrest in G1, blocking the G1/S transition with a maximum significant (p ≤ 0.01) cell count of 80.35% at 25 µg mL-1. No significant changes were observed in S phase, but a decrease in the MCF-7 population was exhibited in G2/M phase.
