Synthesis of silver nanoparticles using Alpinia officinarum rhizome extract induces apoptosis through down-regulating Bcl-2 in human cancer cells

In this study, silver nanoparticles were synthesized using Alpinia officinarum rhizome extract via an eco-friendly green synthesis method. The silver nanoparticles (AO-AgNPs) were characterized by UV-Vis spectrometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and dynamic light scattering. Further, the cytotoxic and apoptotic effects of AO-AgNPs were investigated in human cancer cells with different tissue origins via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay and flow cytometric analyses, respectively. The expression levels of anti-apoptotic Bcl-2 protein were evaluated via a real-time polymerase chain reaction. The synthesized AO-AgNPs induced a significant cytotoxic effect in all tested cancer cells but not in normal cells. AO-AgNPs induced the percentage of apoptotic cells and reduced the levels of anti-apoptotic Bcl-2 mRNA levels in cancer cells. These results demonstrate the potential application of AO-AgNPs in cancer treatment.