Diamond Nanoparticles Modify Curcumin Activity: In Vitro Studies on Cancer and Normal Cells and In Ovo Studies on Chicken Embryo Model

Abstract

Curcumin has been studied broadly for its wide range of biological activities, including anticancer properties. The major problem with curcumin is its poor bioavailability, which can be improved by the addition of carriers, such as diamond nanoparticles (DN). They are carbon allotropes, and are therefore biocompatible and easily taken up by cells. DN are non-toxic and have antiangiogenic properties with potential applications in cancer therapy. Their large surface makes them promising compounds in a drug delivery system for bioactive agents, as DN create bio-complexes in a fast and simple process of self-organisation. We investigated the cytotoxicity of such bio-complexes against liver cancer cells and normal fibroblasts, revealing that conjugation of curcumin with DN significantly improves its activity. The experiment performed in a chicken embryo model demonstrated that neither curcumin nor DN nor bio-complexes affect embryo development, even though DN can form deposits in tissues. Preliminary results confirmed the applicability of DN as an efficient carrier of curcumin, which improves its performance against cancer cells in vitro, yet is not toxic to an organism, which makes the bio-complex a promising anticancer agent.

Toxicity studies of six types of carbon nanoparticles in a chicken-embryo model

“…These results are consistent with previous studies demonstrating that DNPs 18 and pG 16,17 are not harmful to embryonic development.…”

“…There have been several reports in the literature demonstrating the toxicity of different CNPs in various biological embryo models, such as chicken, [16][17][18][19] zebrafish, [20][21][22][23][24][25] and Xenopus laevis. 26,27 For example, carbon nanotubes inhibited angiogenesis of the chorioallantoic membrane in chicken embryos and caused death before day 12 of the incubation period.…”

“…DNPs do not affect embryo development, although they form deposits in the liver tissue. 18 We hypothesized that the various synthesis methods and physicochemical properties of CNPs may potentially impact their toxicity profiles in a fast-growing, highly sensitive organism. To evaluate further the potential risks that CNPs pose to human health, the toxic effects of CNPs on gross pathology, red blood cell (RBC) morphology, and liver biochemistry and oxidative damage were investigated in this study.…”

“…18 Furthermore, an in vitro study 44 demonstrated that adsorption of plasma components by 5 and 100 nm ND (up to 500 µg/mL) had no significant effect on blood plasma protein conformations or coagulation. It has been shown that 100 nm ND is localized around RBCs, while 5 nm particles penetrate RBCs; both sizes of ND, however, neither was toxic at concentrations of 5 and 50 µg/mL.…”

“…Similar results have been reported previously. 4,[16][17][18]29,37 However, because blood serum homeostasis is tightly controlled, the lack of effects on serum indices might not necessarily reflect a lack of toxic effects. Therefore, we also examined the toxic effects of CNPs by screening for oxidative damage status in the livers of chicken embryos.…”