Modares Journal of Biotechnology

Abstract Curcumin, a potent antioxidant extracted from the turmeric plant, is known for its ability to suppress reactive oxygen species (ROS) through activation of antioxidant response elements. However, its clinical utility is limited by poor solubility and rapid elimination. In this study, we aimed to enhance the solubility and bioavailability of curcumin by encapsulating it in fifth-generation polyamidoamine dendrimer nanoparticles. UV-Vis and fluorescence spectroscopy confirmed successful encapsulation, with an average nanoparticle size of 275 nm and a positive surface charge of 8 mV. The nanocarrier exhibited a loading capacity of approximately curcumin6 mol per dendrimer 1mol and achieved complete drug release within 72 hours. Cellular uptake assays using a live/dead assay revealed superior uptake of the nanocarrier compared to free curcumin, leading to a significant reduction in cellular ROS levels and apoptosis. Furthermore, in a model of induced oxidative stress using H2O2, curcumin-loaded dendrimer nanoparticles significantly reduced cellular ROS levels compared to free curcumin. These findings highlight the potential of this nanocarrier as an effective and intelligent system for delivering water-insoluble drugs, offering a promising approach for improving the therapeutic efficacy of curcumin.

Abstract Antioxidant, anticancer, anti-inflammatory, and anti-microbial activities are evidences for the invaluable benefit of this herbal extract in human health and therapy. The anticancer effect of curcumin is due to the targeting of a wide range of cellular and molecular pathways involved in cancer progression. However, the limited solubility, low bioavailability and rapid metabolism of curcumin have a serious negative impact on its therapeutic application. In this research, a nano-carrier with appropriate delivery features, prepared through the conjugation of curcumin to the surface of a polyamidoamine dendrimer at generation 4 (PAMAM). The structure of the synthesized dendrimeric curcumin was confirmed by FT-IR and ¹H-NMR methods. The particles size and zeta potential were measured by Zetasizer. The loading rate of curcumin molecules on nano-carrier investigated and the cell viability, intracellular reactive oxygen species and induction of apoptosis were evaluated using MTT assay and flow cytometry technique in the follows. The results of this study showed that the prepared dendrimeric curcumin had a hydrodynamic diameter of about 100 nm. The results show that the rate of curcumin loading on this nanostructure system was about four curcumin molecules per each dendrimer. Cell experiments indicated that the toxicity, cellular reactive oxygen species (ROS), and apoptosis caused by dendrimeric nano-carrier were higher than free curcumin. Better performance of dendrimer-Nano-carrier was been through the improvement of physicochemical properties and increased curcumin solubility. Overall, it seems that the prepared dendrimeric curcumin is able to significantly improve the delivery of hydrophobic drugs on cancerous cells.