Dendritic polymers are considered as emerging and outstanding carriers as modern medicinal systems due to their derivatisable branched architecture and possibility to modify them in numerous ways. Here, G4.5 PAMAM dendrimers were obtained as carriers of the antipsychotic drug risperidone. Despite their extensive applicability in the pharmaceutical field, the use of dendrimers as carriers in biological systems is constrained due to their inherent associated toxicity. The biocompatibility of dendrimers and dendrimer-risperidone complexes was evaluated in vivo for biological performance. To this end, the pharmacokinetics and biodistribution after oral treatment of free risperidone and dendrimer-risperidone complexes were studied in healthy mice. Also, the behavioral changes such as locomotion, aggression, dominance in male and female mice were evaluated both after a single dose and after daily therapy for 8 days. Also, in vivo effects of risperidone and dendrimer-risperidone complexes on the locomotion of zebrafish larvae were explored. For the treatment, 48-hpf non-hatched zebrafish embryos were placed in each well of a 96-well plate containing E3 medium and incubated for additional 48 h at 28oC. At 4 dpf, the medium was replaced by 250 μl of solutions of the different compounds or E3 (control). For each assay, 12 technical replicates were used for each dilution. Activity events were recorded for 15 min, three timesat 4, 5, 6 and 7 dpf after the addition of the compound tested, at room temperature. Swimming activity was calculated by using the WMicrotracker One system. Data are reported as the averaged activity event recorded for each microbeam pair ± SEM.
Results:
Figure 15 shows the spontaneous swimming activity of zebrafish treated with either free Risp or DG4.5-Risp. When zebrafish were treated with free Risp 25 μM, the swimming activity decrease significantly. However, this decrease was not observed when treated with the same concentration of the drug complexed with DG4.5 dendrimers. A decrease in spontaneous swimming is usually considered as a factor indicating fish toxicity [22,36,37]. Hence, the beneficial effect of dendrimers is to decrease Risp toxicity.
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Nanomedicine & Biotherapeutic Discovery. OMICS Publishing Group. 2013. Maria J. Prieto, 2013
Maria Jimena Prieto, Nahuel Eduardo del Rio Zabala, Cristian Hernán Marotta, Dario Bichara3, Sergio Simonetta, Nadia Silvia Chiaramoni1,2 and Silvia del Valle