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Fluoroquinolones, including ciprofloxacin, are often used to treat bacterial diseases. Due to the spread of drug resistance among microorganisms, alternative treatments are being sought. We report here on the antimicrobial activity of generation 4 (G4) PPI dendrimers in the presence of ciprofloxacin against the reference strains of Gram-positive bacterium Staphylococcus aureus ATCC 6538 and Gram-negative bacterium Escherichia coli ATCC 25922. Cytotoxicity of these compounds was investigated in the eukaryotic B14 Chinese hamster fibroblast cell line, HepG2 human liver hepatocellular carcinoma cell line, mouse neuroblastoma N2a cell line and BRL-3A rat liver cell line. For both strains, the administration of PPI dendrimers along with ciprofloxacin significantly improved its antibacterial effect compared to the cultures given the drug alone. The simultaneous application of dendrimers and ciprofloxacin shows the opportunity of using it at lower doses. Ciprofloxacin and PPI dendrimers are harmful to bacterial strains at the concentrations non-toxic to the eukaryotic cells. [ABSTRACT FROM AUTHOR]

Characterization of dendrimers as potential therapeutics or drug carriers is complete only when toxicity is assessed. There are numerous studies on the influence of surface modification of PAMAM and PPI dendrimers on their cytotoxic properties but without proposing a mechanism for their toxic effect. In this study cytotoxicity profiles of acid-terminated PAMAM G3.5 and amino-terminated PAMAM G4 in comparison to unmodified amino-terminated PPI-G4 and maltotriose modified PPI-G4 dendrimers were checked. Also the mechanism of cell death in Chinese hamster ovary (CHO) and human ovarian carcinoma (SKOV3) cell lines was investigated. The anionic PAMAM G3.5 dendrimers seem to be the most suitable dendrimers for therapeutic applications, because of their high biocompatibility and low cytotoxicity. Cationic PPI-G4 and PAMAM G4 were the most harmful for both CHO and SKOV3 cell lines, especially in high doses. Maltotriose modification has significantly reduced toxicity within the series of PPI-G4 dendrimers. The moderately doxorubicin and cisplatin resistant human ovarian carcinoma SKOV3 cell line was more vulnerable to modified PPI dendrimers than Chinese hamster ovary CHO cell line which does not show resistance to majority of anticancer agents. This unique property makes these dendrimers potentially interesting for an anticancer therapy. [ABSTRACT FROM AUTHOR]

Oligosaccharide-modified poly(propylene imine) dendrimers are promising candidates as drug carriers and as anti-prion agents. Here, we report the biodistribution of maltotriose-modified 4th generation poly(propylene imine) (PPI) dendrimers and their ability to cross the blood–brain–barrier that is important if these glycodendrimers are considered as potential therapeutic agents in the central nervous system (CNS). [ABSTRACT FROM AUTHOR]

Treatment of dendriplexes formed between water-soluble carbosilane dendrimers and phosphorothioate oligodeoxynucleotides (ODN) with the anionic detergent sodium dodecyl sulfate disrupted the complexes indicating that the nature of the union in such dendriplexes is merely electrostatic. However, dendriplexes were not dissociated by serum proteins like bovine or human serum albumins, as assessed by gel electrophoresis and fluorescence experiments. This would imply a dendrimer-mediated protective effect able to prevent ODN interactions with serum proteins and additionally could translate into a reduction of the ODN doses needed to achieve the biological effects. The employment of carbosilane dendrimers as carriers may solve the problem of ODN kidnapping by plasmatic proteins as a key drawback for therapeutics involving ODNs. As examples, transfection processes on normal primary peripheral blood cells and diagnosis of HIV infection in the presence of serum have been assayed.