Vitronectin Absorbed on Nanoparticles Mediate Cell Viability/Proliferation and Uptake by 3T3 Swiss Albino Mouse Fibroblasts: In Vitro Study

Abstract

We study the interaction of 3T3 Swiss albino mouse fibroblasts with polymeric nanoparticles (NPs) and investigate cellular behaviour in terms of viability/cytotoxicity, cell cycle, NPs uptake, MAP kinase (ERK1/2), and focal adhesion kinase (FAK) activation. After incubation of NPs with cell culture media, western blot analysis showed that Vitronectin is retained by NPs, while Fibronectin is not detected. From cytotoxicity studies (MTT and BrdU methods) an LD50 of about 1.5 mg/mL results for NPs. However, NPs in the range 0.01–0.30 mg/mL are able to trigger a statistically significant increase in proliferation and cell cycle progression in dose and time depending manner. Also, biochemical evaluation of ERK1/2 and FAK clearly shows an increasing phosphorylation in a dose and time depending manner. Finally, we found by transmission electron microscopy that NPs are internalised by cells. Competitively blocking VN-integrin receptors with echistatin (1 μg/mL) results in a decrease of viability/proliferation, cell cycle progression, cellular uptake, and FAK/ERK activation showing the involvement of Vitronectin receptors in signal transduction. In conclusion, our results show that cell surface NPs interactions are mediated by absorbed plasma proteins (i.e., Vitronectin) that represent an external stimuli, switched to the nucleus by FAK enzyme, which in turn modulate fibroblasts viability/proliferation.

TiO2 nanoparticles disrupt cell adhesion and the architecture of cytoskeletal networks of human osteoblast‐like cells in a size dependent manner

“…Vinculin is also known to inhibit FAK interactions and phosphorylation and it has been demonstrated previously that vinculin‐depleted cells had increased motility, proliferation, and supressed apoptosis . Increased cell proliferation is also linked with increased phosphorylation of FAK together with cell cycle progression and increased motility . Results herein show that nano‐TiO 2 modified the expression of vinculin in a size dependent manner, that is, decreased expression in Ti5‐treated cells and increased expression in Ti40‐treated cells.…”

Intracellular Signal Modulation by Nanomaterials

“…Rosso et al (2013) have shown that plasma vitronectin bound to certain nanomaterials (maleic anhydride/alkyl vinyl ethers-based NPs) triggers activation of the vitronectin-integrin receptor. This activation leads to increased phosphorylation of ERK1/2 and FAK kinases and increased proliferation and cell cycle progression.…”

“…This activation leads to increased phosphorylation of ERK1/2 and FAK kinases and increased proliferation and cell cycle progression. In addition, the authors found that the NPs were internalized by cells through a direct interaction between the NPs and the vitronectin-integrin receptor (Rosso et al, 2013). …”

Protein adsorption and cellular uptake of AuNPs capped with alkyl acids of different length

“…The serum protein corona is very complex, consisting of various of proteins including apolipoproteins, adhesion mediators, signaling and transport proteins, complement components, and coagulation factors. 34 Therefore, the western blot method was used to investigate the adsorption of the above adhesion mediators (Fn, Vn, Ln and Fgn) from 10% FBS solution ( Fig. 33 It was known that the adhesion mediators such as Fn, Vn, Ln and Fgn can interact with receptors of cells through their RGD domains, which in turn modulate the cellular uptake.…”