Nanoparticle (NP) toxicity is a crucial problem to consider when designing and evaluating new nanoparticle formulations for biomedical and biotechnological applications. NPs can induce stress and cell damage through several different mechanisms, depending on their physico-chemical properties and the biological properties of the exposed cell type. In this study, we analysed the mechanisms of toxicity of polyacrylic acid (PAA) and polyethylenimine (PEI) coated magnetic nanoparticles on mouse melanoma (B16) cell line and primary human myoblasts (MYO). PAA NPs were non-toxic and did not induce ROS formation or activation of the immune response, while PEI NPs significantly reduced cell viability also at low concentrations and induced ROS formation in both cell lines at NP concentrations above 8 µg/ml. Interestingly, PEI NPs induced activation of NF-κB, a major regulator of stress and immune response, only in MYO cells. NF-κB activity was increased 30 min after incubation and then dropped below the basal activity up to 6 h after incubation. PEI NP-induced NF-κB activation indicates activation of stress and immune response in MYO cells.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 11335764Titanium dioxide (TiO2) nanoparticles (NPs) are an important industrial material, also used as additives in cosmetics, pharmaceuticals, and as food colorants, therefore we are frequently exposed to them. Once in the body, NPs are often first picked up by the phagocytic cells of the immune system (e.g. macrophages), which can lead to undesirable interactions between NPs and the immune system and affect its functionality. Exposure to NPs can affect macrophage survival, formation of toxic reactive oxygen intermediates, engulfment of cellular debris by macrophages and antigen presentation to T lymphocytes, which also affects further immune reactions. In this study, human monocytic cell line THP-1 was used to evaluate the toxicity of different concentrations of two types of commercially available titanium dioxide NPs (food-grade (FG) TiO2 and TiO2 P25). Decrease in viability of macrophages was observed only at very high concentrations of P25 NPs (50 in 100 μg/ml), where we also observed an increase in the number of dead cells. Food-grade TiO2 NPs do not exhibit any effect on viability.
D.10 Educational activities
COBISS.SI-ID: 11536468We present new in vitro models for assessing long-term nanotoxicity. Most in vitro nanotoxicology studies analyze only short-term cytotoxicity due to lack of in vitro models that enable long-term exposure. We used biomimetic in vitro urothelium model and L6 rat myoblasts cells with differentiation capability to assess viability after short-term and long-term acute and continuous exposure to i) NPs which we are developing for biomedical applications: polyacrylic acid (PAA) and polyethileneimine (PEI) coated magnetic NPs) and ii) SiO2, TiO2 as commercial types of NPs. We further analyzed induction of ROS, and activation of NF-κB factor with western blot, also expression of genes related to myoblast differentiation with qPCR was analyzed. DLS and zeta potential were determined in relevant physiological media. Overall we observed minimal toxicity on urothelium model except for magnetic PEI NPs while on myoblast model dose dependent toxcicity was observed for TiO2 NPs. The results were presented also with invitied lecture for lay public at the workshop/meeting organised by Ministry of Health: 8. meeting in Chemical safety for all. PAVLIN, Mojca. Kdaj se nanodelci še obnašajo kot nanostrukture pri interakciji z biološkimi sistemi? : predavanje na 8. posvetu Kemijska varnost za vse, 23. 11. 2016, Izola. [COBISS.SI-ID 11641172]
B.04 Guest lecture
COBISS.SI-ID: 11335252