Nanotechnological strategies for the treatment of neglected diseases.

Neglected diseases are prevalent in less developed countries and are associated with high levels of mortality and/or morbidity. The drugs used in clinical practice are toxic, reducing patient compliance, and generally do not result in a cure, and there has also been a surge in drug resistance. Additionally, a major challenge in drug treatment lies in reaching the intracellular sites infected by parasites. The development of nanotechnology-based drug delivery systems for drugs intended to treat neglected diseases is a promising avenue because the use of nanocarriers presents the ability to target drugs to the infected cells, and the prolonged drug release profile possible with these systems permits longer contact between the drug and the parasite. This review describes the roles of colloidal drug carriers, such as liposomes, polymeric nanoparticles and solid lipid nanoparticles, in research on optimizing the delivery of antileishmanial, antitrypanosomal, antichagasic and antimalarial agents.

Pharmacokinetics of curcumin-loaded PLGA and PLGA-PEG blend nanoparticles after oral administration in rats.

The aim of this study was to assess the potential of nanoparticles to improve the pharmacokinetics of curcumin, with a primary goal of enhancing its bioavailability. Polylactic-co-glycolic acid (PLGA) and PLGA-polyethylene glycol (PEG) (PLGA-PEG) blend nanoparticles containing curcumin were obtained by a single-emulsion solvent-evaporation technique, resulting in particles size smaller than 200 nm. The encapsulation efficiency was over 70% for both formulations. The in vitro release study showed that curcumin was released more slowly from the PLGA nanoparticles than from the PLGA-PEG nanoparticles. A LC-MS/MS method was developed and validated to quantify curcumin in rat plasma. The nanoparticles were orally administered at a single dose in rats, and the pharmacokinetic parameters were evaluated and compared with the curcumin aqueous suspension. It was observed that both nanoparticles formulations were able to sustain the curcumin delivery over time, but greater efficiency was obtained with the PLGA-PEG nanoparticles, which showed better results in all of the pharmacokinetic parameters analyzed. The PLGA and PLGA-PEG nanoparticles increased the curcumin mean half-life in approximately 4 and 6h, respectively, and the C(max) of curcumin increased 2.9- and 7.4-fold, respectively. The distribution and metabolism of curcumin decreased when it was carried by nanoparticles, particularly PLGA-PEG nanoparticles. The bioavailability of curcumin-loaded PLGA-PEG nanoparticles was 3.5-fold greater than the curcumin from PLGA nanoparticles. Compared to the curcumin aqueous suspension, the PLGA and PLGA-PEG nanoparticles increased the curcumin bioavailability by 15.6- and 55.4-fold, respectively. These results suggest that PLGA and, in particular, PLGA-PEG blend nanoparticles are potential carriers for the oral delivery of curcumin.