Plant-Based Synthesis of Zinc Oxide Nanoparticles (ZnO-NPs) Using Aqueous Leaf Extract of Aquilegia pubiflora: Their Antiproliferative Activity against HepG2 Cells Inducing Reactive Oxygen Species and Other In Vitro Properties

Abstract

The anti-cancer, anti-aging, anti-inflammatory, antioxidant, and anti-diabetic effects of zinc oxide nanoparticles (ZnO-NPs) produced from aqueous leaf extract of Aquilegia pubiflora were evaluated in this study. Several methods were used to characterize ZnO-NPs, including SEM, FTIR, XRD, DLS, PL, Raman, and HPLC. The nanoparticles that had a size of 34.23 nm as well as a strong aqueous dispersion potential were highly pure, spherical or elliptical in form, and had a mean size of 34.23 nm. According to FTIR and HPLC studies, the flavonoids and hydroxycinnamic acid derivatives were successfully capped. Synthesized ZnO-NPs in water have a zeta potential of -18.4 mV, showing that they are stable solutions. The ZnO-NPs proved to be highly toxic for the HepG2 cell line and showed a reduced cell viability of 23.68 ± 2.1% after 24 hours of ZnO-NP treatment. ZnO-NPs also showed excellent inhibitory potential against the enzymes acetylcholinesterase (IC₅₀: 102 μg/mL) and butyrylcholinesterase (IC₅₀: 125 μg/mL) which are involved in Alzheimer's disease. Overall, the enzymes involved in aging, diabetes, and inflammation showed a moderate inhibitory response to ZnO-NPs. Given these findings, these biosynthesized ZnO-NPs could be a good option for the cure of deadly diseases such as cancer, diabetes, Alzheimer's, and other inflammatory diseases due to their strong anticancer potential and efficient antioxidant properties.

Figure 1

(a) Anti-inflammatory potential of synthesized ZnO-NPs with respect to their control value (68.39 ± 3.17). (b) Antiaging potential of ZnO-NPs with respect to their control value (74.83 ± 3.92). ^∗∗∗Highly significant, ^∗∗slightly significant, and ^∗nonsignificant difference from control at P < 0.05 by one-way ANOVA in the column. Values are mean ± SD of triplicate.

Figure 2

(a) Characteristic pictures of nontreated cells. (b) ZnO-NP-treated cells.

Figure 3

The proposed mechanism of ZnO-NP-mediated cytotoxicity in cancerous cell. NP accumulation and dissolution on the plasma membrane further lead toward lysosome and exert oxidative stress causing generation of ROS. Active ROS causes mitochondrial depolarization and DNA damages finally resulting in cell apoptosis.