Publicação

The uptake, retention and clearance of drug-loaded dendrimer nanoparticles in astrocytes - electrophysiological quantification

Detalhes bibliográficos
Resumo:	Nanoparticle-based drug delivery systems may impose risks to patients due to potential toxicity associated with lack of clearance from cells or prolonged carrier-cell retention. This work evaluates vesicular cell uptake, retention and the possible transfer of endocytosed methylprednisolone-loaded carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles (NPs) into secretory vesicles of rat cultured astrocytes. Cells were incubated with NPs and unitary vesicle fusions/fissions with the plasma membrane were monitored employing high resolution membrane capacitance measurements. In NPs-treated cells the frequency of unitary exocytotic events was significantly increased. The presence of NPs also induce an increase in the size of exocytotic vesicles interacting with the plasma membrane, which exhibit transient fusion with prolonged fusion pore dwell-time. Live-cell confocal imaging revealed that once NPs internalize into endocytotic compartments they remain in the cell for 7 days, although a significant proportion of these merge with secretory vesicles destined for exocytosis. Co-localization studies show the route of clearance of NPs from cells via the exocytotic pathway. These findings bring new insight into the understanding of the intracellular trafficking and biological interactions of drug-loaded dendrimer NPs targeting astrocytes.
Autores principais:	Chowdury, Helena H.
Outros Autores:	Cerqueira, Susana Isabel Ribeiro; Sousa, Nuno; Oliveira, J. M.; Reis, R. L.; Zorec, Robert
Assunto:	Dendrimer nanoparticles Exocytosis/endocytosis Astrocytes High-resolution membrane capacitance Live confocal imaging
Ano:	2018
País:	Portugal
Tipo de documento:	artigo
Tipo de acesso:	acesso aberto
Instituição associada:	Universidade do Minho
Idioma:	inglês
Origem:	RepositóriUM - Universidade do Minho

Descrição
Resumo:	Nanoparticle-based drug delivery systems may impose risks to patients due to potential toxicity associated with lack of clearance from cells or prolonged carrier-cell retention. This work evaluates vesicular cell uptake, retention and the possible transfer of endocytosed methylprednisolone-loaded carboxymethylchitosan/poly(amidoamine) dendrimer nanoparticles (NPs) into secretory vesicles of rat cultured astrocytes. Cells were incubated with NPs and unitary vesicle fusions/fissions with the plasma membrane were monitored employing high resolution membrane capacitance measurements. In NPs-treated cells the frequency of unitary exocytotic events was significantly increased. The presence of NPs also induce an increase in the size of exocytotic vesicles interacting with the plasma membrane, which exhibit transient fusion with prolonged fusion pore dwell-time. Live-cell confocal imaging revealed that once NPs internalize into endocytotic compartments they remain in the cell for 7 days, although a significant proportion of these merge with secretory vesicles destined for exocytosis. Co-localization studies show the route of clearance of NPs from cells via the exocytotic pathway. These findings bring new insight into the understanding of the intracellular trafficking and biological interactions of drug-loaded dendrimer NPs targeting astrocytes.