Chitosan Nanoparticles for Topical Co-Administration of the Antioxidants Glutathione and Idebenone: Characterization and In Vitro Release

Aims: The aim of this study was to explore the potential of novel nanoparticles (NPs) intended for topical administration of the hydrophilic antioxidant Glutathione and the lipophilic Idebenone. Glutathione was introduced into the NPs using two approaches: i) covalently bonded to Chitosan; ii) physically complexed with Idebenone and Sulfobutylether--cyclodextrin. Methodology: NPs were formulated using the ionic gelation technique, by dissolving the polysaccharide-forming matrix (Chitosan, Glycol chitosan, Glutathionyl Chitosan) in water or in slightly acidic solution. Idebenone was physically entrapped whereas glutathione was either physically entrapped or covalently bonded to chitosan. Physicochemical characterization of the resulting NPs included size, zeta potential measurements, antioxidant association efficiency, differential scanning calorimetry (DSC) and stability studies. Antioxidants in vitro release from the most stable NPs was assessed with Franz diffusion cells, and the in vitro antioxidant activity was evaluated by the 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical test. NP cytotoxicity was assessed on immortalized human keratinocytes (HaCaT) cell line. Results: The NPs showed smaller particle size in acidic solution than in aqueous medium, whereas zeta potential values were always positive, irrespective of the medium. Stability studies led to the choice of the aqueous formulation where Glutathione was covalently bonded to Chitosan for this study. DSC highlighted amorphization of Idebenone in these NPs. In vitro release studies showed that only Idebenone was released from the NPs. The antioxidant activity test revealed a strong effect (close to 100%) of Idebenone loaded into NPs while its aqueous solution showed no activity. No cytotoxicity in human keratinocytes was observed for the investigated NPs. Conclusion: The results of this study suggest that Idebenone can be loaded into a hydrophilic delivery system without organic solvents, often used for its solubilization, possessing high antioxidant activity. Therefore, these nanocarriers represent a promising strategy for the design of formulations for topical treatments with antioxidants

Chitosan Nanoparticles for Topical Co-Administration of the Antioxidants Glutathione and Idebenone: Characterization and In Vitro Release

Aims: The aim of this study was to explore the potential of novel nanoparticles (NPs) intended for topical administration of the hydrophilic antioxidant Glutathione and the lipophilic Idebenone. Glutathione was introduced into the NPs using two approaches: i) covalently bonded to Chitosan; ii) physically complexed with Idebenone and Sulfobutylether--cyclodextrin. Methodology: NPs were formulated using the ionic gelation technique, by dissolving the polysaccharide-forming matrix (Chitosan, Glycol chitosan, Glutathionyl Chitosan) in water or in slightly acidic solution. Idebenone was physically entrapped whereas glutathione was either physically entrapped or covalently bonded to chitosan. Physicochemical characterization of the resulting NPs included size, zeta potential measurements, antioxidant association efficiency, differential scanning calorimetry (DSC) and stability studies. Antioxidants In vitro release from the most stable NPs was assessed with Franz diffusion cells, and the In vitro antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. NP cytoxicity was assessed on immortalized human keratinocytes (HaCaT) cell lines. Results: The NPs showed smaller particle size in acidic solution than in aqueous medium, whereas zeta potential values were always positive, irrespective of the medium. Stability studies led to the choice of the aqueous formulation where Glutathione was covalently bonded to Chitosan for this study. DSC highlighted amorphization of Idebenone in these NPs. In vitro release studies showed that only Idebenone was released from the NPs. The antioxidant activity test revealed a strong effect (close to 100%) of Idebenone loaded into NPs while its aqueous solution showed no activity. No cytotoxicity in human keratinocytes was observed for the investigated NPs. Conclusion: The results of this study suggest that Idebenone can be loaded into a hydrophilic delivery system without organic solvents, often used for its solubilization, possessing high antioxidant activity. Therefore, these nanocarriers represent a promising strategy for the design of formulations for topical treatments with antioxidants

Mucoadhesive Properties and Interaction with P-glycoprotein (P-gp) of Thiolated-Chitosans and -Glycol Chitosans and Corresponding Parent Polymers: A Comparative Study

The aim of the present work was to compare the mucoadhesive and efflux pump P-glycoprotein (P-gp) interacting properties of chitosan (CS)- and glycolchitosan (GCS)-based thiomers and corresponding unmodified parent polymers. For this purpose, the glycol chitosan-N-acetyl-cysteine (GCS-NAC) and glycol chitosan-glutathione (GCS-GSH) thiomers were prepared under simple and mild conditions. Their mucoadhesive characteristics were studied by turbidimetric and zeta potential measurements. The P-gp interacting properties were evaluated measuring the effects of thiolated- and unmodified-polymers on the bidirectional transport (BA/AB) of rhodamine-123 across Caco-2 cells as well as in the calcein-AM and ATPase activity assays. Although all the thiomers and unmodified polymers showed optimal-excellent mucoadhesive properties, the best mucoadhesive performances have been obtained by CS and CS-based thiomers. Moreover, it was found that the pretreatment of Caco-2 cell monolayer with GCS-NAC or GCS restores Rho-123 cell entrance by inhibiting P-gp activity. Hence, GCS-NAC and GCS may constitute new biomaterials useful for improving the bioavailability of P-gp substrates

Effects of cyberknife radiotherapy treatment of pituitary adenomas

none11nononePuglisi, Soraya; Cotta, Oana Ruxandra; Conti, Alfredo; Pontoriero, Antonio; Messina, Erika; Albani, Adriana; Ferrau, Francesco; Ragonese, Marta; Torre, Maria Luisa; Angileri, Flavio; Cannavo, SalvatorePuglisi, Soraya; Cotta, Oana Ruxandra; Conti, Alfredo; Pontoriero, Antonio; Messina, Erika; Albani, Adriana; Ferrau, Francesco; Ragonese, Marta; Torre, Maria Luisa; Angileri, Flavio; Cannavo, Salvator

Intranasal delivery of dopamine to the striatum using glycol chitosan/sulfobutylether cyclodextrin based nanoparticles

The aim of this study was to evaluate chitosan (CS)-, glycol chitosan (GCS)- and corresponding thiomer-based nanoparticles (NPs) for delivering dopamine (DA) to the brain by nasal route. Thus, the polyanions tripolyphosphate and sulfobutylether-β-cyclodextrin (SBE-β-CD), respectively, were used as polycation crosslinking agents and SBE-β-CD also in order to enhance the DA stability. The most interesting formulation, containing GCS and SBE-β-CD, was denoted as DA GCS/DA-CD NPs. NMR spectroscopy demonstrated an inclusion complex formation between SBE-β-CD and DA. X-ray photoelectron spectroscopy analysis revealed the presence of DA on the external surface of NPs. DA GCS/DA-CD NPs showed cytotoxic effect toward Olfactory Ensheathing Cells only at higher dosage. Acute administration of DA GCS/DA-CD NPs into the right nostril of rats did not modify the levels of the neurotransmitter in both right and left striatum. Conversely, repeated intranasal administration of DA GCS/DA-CD NPs into the right nostril significantly increased DA in the ipsilateral striatum. Fluorescent microscopy of olfactory bulb after acute administration of DA fluorescent-labeled GCS/DA-CD NPs into the right nostril showed the presence of NPs only in the right olfactory bulb and no morphological tissue damage occurred. Thus, these GCS based NPs could be potentially used as carriers for nose-to-brain DA delivery for the Parkinson's disease treatment