ABSTRACT
Functionalized carbon nanotubes (CNTs) have been proposed in the last years as vectors for delivery of biomolecules, proteins and DNA into various cells. In this study, a new multiwalled carbon nanotube ß-cyclodextrin platform (MWCNT-CD) modified with branched polyethylenimine (PEI) and doped with Rhodamine (Rhod), MWCNT-CD-PEI-Rhod, was designed and investigated as drug delivery system. The drug binding abilities of MWCNT-CD-PEI-Rhod towards Cidofovir (Cid) and DNA plasmid encoding enhanced green fluorescence protein (pCMS-EGFP) were investigated by complementary spectroscopic techniques. MWCNT-CD-PEI-Rhod showed no significative cytotoxicity and an excellent ability to entrap and delivery Cid. The present study broadens the spectrum of biological evaluation by investigating platform-treatment induced cellular response such as antiviral activity, transfection properties, cellular uptake, internalization mechanisms and cellular localization. The mechanism of cellular uptake was elucidated monitoring the dependence of intracellular red fluorescence from the assembly concentration, time and presence of specific uptake inhibitors. The biological results indicated that MWCNT-CD-PEI-Rhod loaded with Cid and/or pCMS-EGFP crossed the cell membrane via clathrin-dependent pathway and co-localized in lysosomal compartment. However, no green fluorescent protein expression of pCMS-EGFP was detected, whereas the efficient escape of Cid from lysosome and the release close to nuclear region prompted the antiviral activity.
Subject(s)
Antiviral Agents/pharmacology , Cytosine/analogs & derivatives , Drug Carriers , Nanotubes, Carbon/chemistry , Organophosphonates/pharmacology , Polyethyleneimine/chemistry , beta-Cyclodextrins/chemistry , Animals , Antiviral Agents/chemistry , Biological Transport , Chlorocebus aethiops , Cidofovir , Cytomegalovirus/drug effects , Cytomegalovirus/growth & development , Cytosine/chemistry , Cytosine/pharmacology , Drug Liberation , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Kinetics , Lysosomes/drug effects , Lysosomes/metabolism , Organophosphonates/chemistry , Plasmids/chemistry , Plasmids/metabolism , Rhodamines/chemistry , Rhodamines/metabolism , Vero CellsABSTRACT
The aim of the present research was to determine the effect of almond skin extracts on herpes simplex virus 1 (HSV-1) replication. Drug-resistant strains of HSV frequently develop following therapeutic treatment. Therefore, the discovery of novel anti-HSV drugs deserves great effort. Here, we tested both natural (NS) and blanched (BS) polyphenols-rich almond skin extracts against HSV-1. HPLC analysis showed that the prevalent compounds in NS and BS extracts contributing to their antioxidant activity were quercetin, epicatechin and catechin. Results of cell viability indicated that NS and BS extracts were not toxic to cultured Vero cells. Furthermore, NS extracts were more potent inhibitors of HSV-1 than BS extracts, and this trend was in agreement with different concentrations of flavonoids. The plaque forming assay, Western blot and real-time PCR were used to demonstrate that NS extracts were able to block the production of infectious HSV-1 particles. In addition, the viral binding assay demonstrated that NS extracts inhibited HSV-1 adsorption to Vero cells. Our conclusion is that natural products from almond skin extracts are an extraordinary source of antiviral agents and provide a novel treatment against HSV-1 infections.
