Cerium nanoparticles synthesized using aqueous extract of Centella asiatica: characterization, determination of free radical scavenging activity and evaluation of efficacy against cardiomyoblast hypertrophy

Cerium nanoparticles (CeNPs) are used in biomedical applications due to their autocatalytic properties. Even though their use in the management of neurodegenerative diseases, diabetes, etc. has been reported, their role in cardiovascular disease management remains largely unexploited. Moreover, conventional procedures for synthesizing metal nanoparticles are non-environmentally friendly and require high-priced chemicals. Therefore, there is a need for eco friendly and cost effective "green technologies" for CeNP synthesis. This study is the first of its kind to green synthesize, characterize, and evaluate the efficacy of CeNPs against cardiomyoblast hypertrophy. CeNPs were synthesized using 1 : 5 volume ratios of Centella asiatica aqueous extract and an aqueous solution of cerium ammonium nitrate, and were characterized by various methods such as UV-visible spectroscopy, DLS, SEM and HRTEM, EDX, etc. The particles were demonstrated to be spherical and monodispersed with 8 nm diameter. Zeta potential was found to be negative. Superoxide and hydroxyl radical scavenging activities of CeNPs were found to be higher when compared to bulk cerium and the extract. H9c2 rat cardiomyoblasts were used for cell line studies. Flow cytometry and fluorescence imaging were employed for the cell line experiments. High cellular uptake and viability were revealed for CeNPs when compared to macro counterparts. Intracellular superoxide anion generation was less on incubation with higher concentrations of CeNPs. Moreover, preliminary results provided an insight into the potential of CeNPs in attenuating isoproterenol-stimulated cardiomyoblast hypertrophy and has been linked to the inhibition of intracellular calcium overload and reactive oxygen species.