Effect of inhibitors of endocytosis and NF-kB signal pathway on folate-conjugated nanoparticle endocytosis by rat Kupffer cells

Abstract

The regular accumulation of nanoparticles in the liver makes them hepatotoxic and decreases the circulation time, thus reducing their therapeutic effect. Resolving this problem will be significant in improving bioavailability and reducing side effects. In this study, we reduced the phagocytosis of epirubicin (EPI)-loaded folic acid-conjugated pullulan acetate (FPA/EPI) nanoparticles by Kupffer cells (KCs) through internalization and nuclear factor kappa B (NF-kB) signal pathway inhibitors, thus allowing development of FPA/EPI nanoparticles as a nanodrug delivery system (NDDS) based on our previous study. FPA/EPI nanoparticles were prepared by the dialysis method. Rat KCs were preincubated with the following individual or compound inhibitors: chlorpromazine (CPZ), nystatin (NY), colchicine (Col), amiloride (AMR), and pyrrolidine dithiocarbamate (PDTC). Dose- and time-dependent cellular uptake effects of inhibitors on FPA/EPI nanoparticles were determined through fluorometry. The cytokine levels of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and IL-6 were tested in culture supernatants by bead-based multiplex flow cytometry. The uptake study demonstrated that inhibitors had an obvious inhibitory effect ( P <0.05 or P <0.01), with NY, AMR and Col all showing time-dependent inhibitory effects. PDTC + NY had the strongest inhibitory effect, with an uptake rate of 14.62%. The levels of the three proinflammatory cytokines were changed significantly by the compound inhibitors. TNF-α was significantly inhibited ( P <0.05 or P <0.01), but IL-1β and IL-6 showed smaller decreases. These results suggested that clathrin- and caveolae-mediated endocytosis were the main routes via which nanoparticles entered KCs and that the NF-kB signal pathway was very important too. In summary, multiple mechanisms, including clathrin- and caveolae-mediated endocytosis, contribute to cytokine production in macrophages following exposure to folic acid-conjugated pullulan acetate nanoparticles. Thus, the endocytosis inhibition strategy has great potential for improving therapy and reducing toxicity of an NDDS in the treatment of cancer.

Angiopoietin-2 induces angiogenesis via exosomes in human hepatocellular carcinoma

“…Genomic DNA sequencing detected mutations in the ANGPT2 gene in stable cell lines (c). Immunoblotting showed the expression levels of ANGPT2 in the stable cell lines and their exosomes, which showed that the levels of exosomal ANGPT2 were decreased correspondingly (d) associates with endocytosis, we used the endocytosis inhibitors nystatin and amiloride to treat HUVECs before coculture [32], and we found that the internalization process of exosomal ANGPT2 was blocked ( Fig. 2c, d), suggesting that HCC cell-secreted exosomal ANGPT2 is delivered into HUVECs via exosome endocytosis.…”

<p>Combination Treatment of Cervical Cancer Using Folate-Decorated, pH-Sensitive, Carboplatin and Paclitaxel Co-Loaded Lipid-Polymer Hybrid Nanoparticles</p>

“…40 In the study carried out by Tang et al, the cellular uptake and cellular internalization mechanisms of nanoparticles in HeLa (high expression of FA receptor) cells were quantitatively detected by the fluorescence method. 41 In the FA receptor-overexpressing HeLa cells, the internalization of FA-decorated nanoparticles was significantly more efficient than undecorated ones due to FA receptormediated endocytosis and cellular macropinocytosis involved in the cellular internalizations of nanoparticles in HeLa cells. Also, the pH-triggered payload release leads to the increased cumulation of drugs in the cells.…”

Quantum Dots as a Good Carriers of Unsymmetrical Bisacridines for Modulating Cellular Uptake and the Biological Response in Lung and Colon Cancer Cells

“…These factors can determine whether and how NPs enter into the cells by CME, as well as affecting the uptake of NPs into cancer cells through multiple receptors on the cell membrane. Moreover, the mechanism of the internalization of NPs into cells depends on several variables, including the cell type, particle size, material composition, shape, and surface properties [ 29 ]. The multiple pathway internalization of QD−UA hybrids (especially QDs–C-2028) can provide an explanation of their higher cellular uptake and cytotoxicity in H460 cells, compared to UAs alone.…”