Abstract
Abstract:
Metallic nanoparticles (NPs) especially silver (Ag) NPs have shown immense potential in medical
applications due to their distinctive physio-chemical and biological properties. This article
reports the conjugation of Ag NPs with Rubus fairholmianus extract. The modification of Ag NPs was
confirmed using various physico-chemical characterization techniques. The cytotoxic effect of
Rubus-conjugated Ag NPs (RAgNPs) was studied by LDH assay and proliferation by ATP assay. The
apoptotic inducing ability of the NPs were investigated by Annexin V/PI staining, caspase 3/7
analysis, cytochrome c release, intracellular ROS analysis, Hoechst staining and mitochondrial
membrane potential analysis using flow cytometry. The expression of apoptotic proteins caspase 3,
Bax and P53 were analyzed using ELISA and caspase 3, Bax using western blotting. Cells treated with
10 µg/mL RAgNPs showed an increased number of cell death by microscopic analysis compared to
untreated control cells. The RAgNPs induced a statistically significant dose-dependent decrease in
proliferation (p < 0.001 for
5 and 10 µg/mL) and increased cytotoxicity in MCF-7 cells. A 1.83 fold increase in cytotoxicity was
observed in cells treated with 10 µg/mL (p < 0.05) compared to the untreated cells. Nuclear damage
and intracellular ROS production were observed upon treatment with all tested concentrations of
RAgNPs and the highest concentrations (5 and 10 µg/mL) showed significant (p < 0.05, p < 0.01)
expression of caspase 3, Bax and P53 proteins. The data strongly suggest that RAgNPs induces cell
death in MCF-7 cells through the mitochondrial-mediated intrinsic apoptosis pathway. The present
investigation
supports the potential of RAgNPs in anticancer drug development.