Enhancing Antioxidant Cellular Defense by Using Quercetin Loaded TiO2 Nanoparticles in Swiss 3T3 Albino Mouse Fibroblast Cells

Abstract

Living organisms are continuously exposed to a wide variety of oxidative radicals. Therefore, there is a constant demand for exogenous antioxidant supply. In this regard, one of these exogenous antioxidants with well established potency, quercetin has been utilized in various formulations. Yet due to its poor water solubility, its extensive applications are limited so far. In this study, TiO 2 nanoparticles (TiO 2 -NPs) were employed to improve the cellular penetration of quercetin and to maximize its antioxidant effects on swiss 3T3 albino mouse fibroblast cells. Surfaces of TiO 2 -NPs were modified with Polyethylene glycol (PEG) that enabled better dispersion and enhanced biocompatibility. Toxicity of quercetin and quercetin loaded TiO 2 NPs (QL-TiO 2 -NPs) were evaluated in terms of cell morphology and measured with cell viability assay. For an in-depth cell viability analysis, key markers of apoptosis were investigated by immunoblotting analysis. As an indicator of apoptotic cell death, cleavage of caspase 3 (Cas 3) and poly (ADP-ribose) polymerase proteins (Parp) were detected in quercetin treated cells. Antioxidant capacity of quercetin in the form of QL-TiO 2 -NPs was measured in the cells in which generation of reactive oxygen species (ROS) and superoxide was induced by pyocyanin. Quantitative ROS measurements were confirmed with confocal microscopy. Further mechanistic insight on upregulation of NF-E2 related factor 2 (NRF2) pathway via QL-TiO 2 -NPs was also provided in an effort to validate its antioxidant defense. Target enzymes of NRF2, heme oxygenase-1 (HO-1), NAD(P)H: quinone oxydoreductase1 (NQO1) and superoxide dismutase1 (SOD1) expressions were increased in the model proposed. QL-TiO 2 -NPs allowed high bioavaliability of quercetin concentration and stability in the cell with maximum antioxidant capacity against formation of ROS without any cytotoxicity. Overall, this paper sheds light on how the efficiency of quercetin in a nanosystem can serve as a safe therapeutic candidate for breaking the vicious ROS cycle in the cell. Citation: Birinci Y, Niazi JH, Basaga H (2017) Enhancing Antioxidant Cellular Defense by Using Quercetin Loaded TiO 2 Nanoparticles in Swiss 3T3Albino Mouse Fibroblast Cells. J Nanomedic Nanotechnol S8: 001. doi:10.4172/2157-7439.S8-001Page 2 of 10 J Nanomedic Nanotechnol Nanotechnology: Challenges and Perspectives in Medicine ISSN: 2157-7439 JNMNT an open access journal 3T3 albino mouse fibroblast cells. Total cellular ROS and superoxide levels in treated cells were determined and compared with those of control cells. However, quercetin in a nanosystem shows maximum antioxidant activity by triggering NRF2 pathway, upregulating phase II antioxidant enzymes, heme oxygenase-1 (HO-1), NAD(P)H: quinone oxydoreductase1 (NQO1) and superoxide dismutase1 (SOD1). In summary, our study demonstrated that quercetin loaded TiO 2 -NPs served as an effective nanosystem for delivering quercetin to swiss 3T3 albino mouse fibroblast cells in vitro and provided protection against oxida...