TY - JOUR
T1 - Glutathione conjugation dose-dependently increases brain-specific liposomal drug delivery in vitro and in vivo
AU - Maussang, David
AU - Rip, Jaap
AU - van Kregten, Joan
AU - van den Heuvel, Angelique
AU - van der Pol, Susanne
AU - van der Boom, Burt
AU - Reijerkerk, Arie
AU - Chen, Linda
AU - de Boer, Marco
AU - Gaillard, Pieter
AU - de Vries, Helga
N1 - Funding Information: This research was funded by AgentschapNL (grant INT111045 ). The authors would like to thank Corine Visser for editorial editing, Tom Foster and Leonie Hoogterp for the extraction of HUVEC cells. We also thank Pierre-Olivier Couraud for providing the hCMEC/D3 cell line. Publisher Copyright: © 2016 Elsevier Ltd
PY - 2016/6/1
Y1 - 2016/6/1
N2 - The blood–brain barrier (BBB) represents a major obstacle for the delivery and development of drugs curing brain pathologies. However, this biological barrier presents numerous endogenous specialized transport systems that can be exploited by engineered nanoparticles to enable drug delivery to the brain. In particular, conjugation of glutathione (GSH) onto PEGylated liposomes (G-Technology®) showed to safely enhance delivery of encapsulated drugs to the brain. Yet, understanding of the mechanism of action remains limited and full mechanistic understanding will aid in the further optimization of the technology. In order to elucidate the mechanism of brain targeting by GSH-PEG liposomes, we here demonstrate that the in vivo delivery of liposomal ribavirin is increased in brain extracellular fluid according to the extent of GSH conjugation onto the liposomes. In vitro, using the hCMEC/D3 human cerebral microvascular endothelial (CMEC) cell line, as well as primary bovine and porcine CMEC (and in contrast to non-brain derived endothelial and epithelial cells), we show that liposomal uptake occurs through the process of endocytosis and that the brain-specific uptake is also glutathione conjugation-dependent. Interestingly, the uptake mechanism is an active process that is temperature-, time- and dose-dependent. Finally, early endocytosis events rely on cytoskeleton remodeling, as well as dynamin- and clathrin-dependent endocytosis pathways. Overall, our data demonstrate that the glutathione-dependent uptake mechanism of the G-Technology involves a specific endocytosis pathway indicative of a receptor-mediated mechanism, and supports the benefit of this drug delivery technology for the treatment of devastating brain diseases.
AB - The blood–brain barrier (BBB) represents a major obstacle for the delivery and development of drugs curing brain pathologies. However, this biological barrier presents numerous endogenous specialized transport systems that can be exploited by engineered nanoparticles to enable drug delivery to the brain. In particular, conjugation of glutathione (GSH) onto PEGylated liposomes (G-Technology®) showed to safely enhance delivery of encapsulated drugs to the brain. Yet, understanding of the mechanism of action remains limited and full mechanistic understanding will aid in the further optimization of the technology. In order to elucidate the mechanism of brain targeting by GSH-PEG liposomes, we here demonstrate that the in vivo delivery of liposomal ribavirin is increased in brain extracellular fluid according to the extent of GSH conjugation onto the liposomes. In vitro, using the hCMEC/D3 human cerebral microvascular endothelial (CMEC) cell line, as well as primary bovine and porcine CMEC (and in contrast to non-brain derived endothelial and epithelial cells), we show that liposomal uptake occurs through the process of endocytosis and that the brain-specific uptake is also glutathione conjugation-dependent. Interestingly, the uptake mechanism is an active process that is temperature-, time- and dose-dependent. Finally, early endocytosis events rely on cytoskeleton remodeling, as well as dynamin- and clathrin-dependent endocytosis pathways. Overall, our data demonstrate that the glutathione-dependent uptake mechanism of the G-Technology involves a specific endocytosis pathway indicative of a receptor-mediated mechanism, and supports the benefit of this drug delivery technology for the treatment of devastating brain diseases.
UR - http://www.scopus.com/inward/record.url?scp=85003944821&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.ddtec.2016.09.003
DO - https://doi.org/10.1016/j.ddtec.2016.09.003
M3 - Review article
C2 - 27986226
SN - 1740-6749
VL - 20
SP - 59
EP - 69
JO - Drug Discovery Today: Technologies
JF - Drug Discovery Today: Technologies
ER -