Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the gold-standard drug available for treating PD. Curcumin has many ...pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, and antitumor properties. Copolymers composed of Poly (ethylene oxide) (PEO) and biodegradable polyesters such as Poly (ε-caprolactone) (PCL) can self-assemble into nanoparticles (NPs). This study describes the development of NH
-PEO-PCL diblock copolymer positively charged and modified by adding glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA curcumin that would be able to pass the blood-brain barrier.
The NH
-PEO-PCL NPs suspensions were prepared by using a nanoprecipitation and solvent displacement method and coated with GSH. NPs were submitted to characterization assays. In order to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NPs to observe cytotoxicity.
NPs have successfully loaded L-DOPA and curcumin and were stable after freeze-drying, indicating advancing into in vitro toxicity testing. Vero and PC12 cells that were treated up to 72 h with various concentrations of L-DOPA and curcumin-loaded NP maintained high viability percentage, indicating that the NPs are biocompatible.
NPs consisting of NH
-PEO-PCL were characterized as potential formulations for brain delivery of L-DOPA and curcumin. The results also indicate that the developed biodegradable nanomicelles that were blood compatible presented low cytotoxicity.
Background
Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the standard gold drug available for the treatment of PD. Curcumin has ...a wide range of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, antitumor properties. Copolymers composed of poly(ethylene oxide) (PEO) and biodegradable polyesters like poly(ε-caprolactone) (PCL) that can self-assemble into nanoparticles (NP). This study describes the development of NH2-PEO-PCL diblock copolymer positively charged and modified by the addition of glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA and curcumin that would be able to pass the blood-brain barrier.
Methods
The NH2-PEO-PCL nanoparticles suspensions were prepared using a nanoprecipitation and solvent displacement method and were coated with GSH. NP was submitted to various characterizations assays, and to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NP to observe cytotoxicity.
Results
NP has successfully loaded L-DOPA and curcumin was stable after freeze-drying, capable of advancing into in vitro toxicity testing. After being treated up to 72 hours of various concentrations of L-DOPA and curcumin loaded NP Vero and PC12 cells, the viability of the treated cells maintained a high percentage indicating that the NPs are biocompatible.
Conclusions
NP consisting of NH2-PEO-PCL have been characterized as potential formulations for brain delivery of L-DOPA and curcumin, and obtained results also indicate that the developed biodegradable nanomicelles were blood compatible, presented low cytotoxicity even in longer exposure times.
Lycopene is a carotenoid with potential use in the treatment of chronic illnesses. Here, different formulations of lycopene were studied: lycopene-rich extract from red guava (LEG), purified lycopene ...from red guava (LPG) and a self-emulsifying drug delivery system loaded with LPG (nanoLPG). The effects of administering orally various doses of LEG to hypercholesterolemic hamsters were evaluated regarding the liver function of the animals. The cytotoxicity of LPG in Vero cells was analyzed by a crystal violet assay and by fluorescence microscopy. In addition, nanoLPG was employed in stability tests. LPG and nanoLPG were tested for their cytotoxic effect on human keratinocytes and antioxidant capacity on cells in an endothelial dysfunction model in an isolated rat aorta. Finally, the effect of different nanoLPG concentrations on the expression of immune-related genes (
,
α,
and
-γ) from peripheral blood mononuclear cells (PBMC) using real-time PCR was also analyzed. Results suggest that LEG, despite not being able to improve blood markers indicative of liver function in hypercholesterolemic hamsters, reduced hepatic degenerative changes. Additionally, LPG did not show cytotoxicity in Vero cells. In relation to nanoLPG, the effects produced by heat stress evaluated by Dynamics Light Scattering (DLS) and visually were loss of color, texture change and phase separation after 15 days without interfering with the droplet size, so the formulation proved to be efficient in stabilizing the encapsulated lycopene. Although LPG and nanoLPG showed moderate toxicity to keratinocytes, which may be related to cell lineage characteristics, both revealed potent antioxidant activity. LPG and nanoLPG showed vasoprotective effects in aortic preparations. The gene expression assay indicates that, although no significant differences were observed in the expression of
and
, the PBMCs treated with nanoLPG showed a reduction in transcriptional levels of
and an increased expression of
. Thus, the work adds evidence to the safety of the use of lycopene by humans and shows that tested formulations, mainly nanoLPG due to its stability, stand out as promising and biosafe products for the treatment of diseases that have oxidative stress and inflammation in their etiopathology.