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On guanidinium and cellular uptake.

Wexselblatt E, Esko JD, Tor Y - J. Org. Chem. (2014)

Bottom Line: Although impressive uptake has been demonstrated for nonoligomeric and nonpept(o)idic guanidinylated scaffolds in cell cultures and animal models, the fundamental understanding of these processes is lacking.Charge pairing and hydrogen bonding with cell surface counterparts have been proposed, but their exact role remains putative.The impact of the number and spatial relationships of the guanidinium groups on delivery and organelle/organ localization is yet to be established.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry and ‡Department of Cellular and Molecular Medicine, University of California , San Diego 9500 Gilman Dr., La Jolla, California 92093, United States.

ABSTRACT
Guanidinium-rich scaffolds facilitate cellular translocation and delivery of bioactive cargos through biological barriers. Although impressive uptake has been demonstrated for nonoligomeric and nonpept(o)idic guanidinylated scaffolds in cell cultures and animal models, the fundamental understanding of these processes is lacking. Charge pairing and hydrogen bonding with cell surface counterparts have been proposed, but their exact role remains putative. The impact of the number and spatial relationships of the guanidinium groups on delivery and organelle/organ localization is yet to be established.

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GNeo-QD525 conjugate colocalizes with lysosomes. Wild-typeChinesehamster ovary cells were incubated with 5 nmol/L GNeo-QD525 in growthmedium for 30 min. After the cells were rinsed three times, freshmedium was added, and 2.5 h later, they were rinsed with Hank’sbalanced salt solution and labeled with Hoechst dye and LysoTrackerRed. Images were captured with a DeltaVision Restoration microscopesystem and were deconvolved to show the localization of (a) GNeo-QD525and (b) lysosomes in a single Z-stack plane. The merged images from(a) and (b) are shown in (c) with the outline of cells (hatched line)drawn based on a phase contrast micrograph. Reprinted with permissionfrom ref (46). Copyright2010 Nature Publishing Group.
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fig5: GNeo-QD525 conjugate colocalizes with lysosomes. Wild-typeChinesehamster ovary cells were incubated with 5 nmol/L GNeo-QD525 in growthmedium for 30 min. After the cells were rinsed three times, freshmedium was added, and 2.5 h later, they were rinsed with Hank’sbalanced salt solution and labeled with Hoechst dye and LysoTrackerRed. Images were captured with a DeltaVision Restoration microscopesystem and were deconvolved to show the localization of (a) GNeo-QD525and (b) lysosomes in a single Z-stack plane. The merged images from(a) and (b) are shown in (c) with the outline of cells (hatched line)drawn based on a phase contrast micrograph. Reprinted with permissionfrom ref (46). Copyright2010 Nature Publishing Group.

Mentions: Guanidinoglycosides can translocatelarge bioactive molecules throughcell membranes.46 When biotinylated GNeois conjugated to streptavidin-coated quantum dots (QD525), approximately90% of internalized nanoparticles colocalize with lysosomes after3 h, suggesting that GNeo can deliver very high molecular weight cargo(>107 Da) to these organelles (Figure 5).46 To facilitate conjugationof diverse biomolecules, an N-hydroxysuccinimideactivated ester of guanidinoneomycin was prepared (GNeo-NHS, Scheme 1).46 Two lysosomal enzymes,β-d-glucuronidase and α-l-iduronidase,were conjugated to GNeo without interfering with their enzymatic activityand delivered to patient cells lacking the corresponding lysosomalenzyme in sufficient amounts to restore normal turnover of glycosaminoglycans.46


On guanidinium and cellular uptake.

Wexselblatt E, Esko JD, Tor Y - J. Org. Chem. (2014)

GNeo-QD525 conjugate colocalizes with lysosomes. Wild-typeChinesehamster ovary cells were incubated with 5 nmol/L GNeo-QD525 in growthmedium for 30 min. After the cells were rinsed three times, freshmedium was added, and 2.5 h later, they were rinsed with Hank’sbalanced salt solution and labeled with Hoechst dye and LysoTrackerRed. Images were captured with a DeltaVision Restoration microscopesystem and were deconvolved to show the localization of (a) GNeo-QD525and (b) lysosomes in a single Z-stack plane. The merged images from(a) and (b) are shown in (c) with the outline of cells (hatched line)drawn based on a phase contrast micrograph. Reprinted with permissionfrom ref (46). Copyright2010 Nature Publishing Group.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4120969&req=5

fig5: GNeo-QD525 conjugate colocalizes with lysosomes. Wild-typeChinesehamster ovary cells were incubated with 5 nmol/L GNeo-QD525 in growthmedium for 30 min. After the cells were rinsed three times, freshmedium was added, and 2.5 h later, they were rinsed with Hank’sbalanced salt solution and labeled with Hoechst dye and LysoTrackerRed. Images were captured with a DeltaVision Restoration microscopesystem and were deconvolved to show the localization of (a) GNeo-QD525and (b) lysosomes in a single Z-stack plane. The merged images from(a) and (b) are shown in (c) with the outline of cells (hatched line)drawn based on a phase contrast micrograph. Reprinted with permissionfrom ref (46). Copyright2010 Nature Publishing Group.
Mentions: Guanidinoglycosides can translocatelarge bioactive molecules throughcell membranes.46 When biotinylated GNeois conjugated to streptavidin-coated quantum dots (QD525), approximately90% of internalized nanoparticles colocalize with lysosomes after3 h, suggesting that GNeo can deliver very high molecular weight cargo(>107 Da) to these organelles (Figure 5).46 To facilitate conjugationof diverse biomolecules, an N-hydroxysuccinimideactivated ester of guanidinoneomycin was prepared (GNeo-NHS, Scheme 1).46 Two lysosomal enzymes,β-d-glucuronidase and α-l-iduronidase,were conjugated to GNeo without interfering with their enzymatic activityand delivered to patient cells lacking the corresponding lysosomalenzyme in sufficient amounts to restore normal turnover of glycosaminoglycans.46

Bottom Line: Although impressive uptake has been demonstrated for nonoligomeric and nonpept(o)idic guanidinylated scaffolds in cell cultures and animal models, the fundamental understanding of these processes is lacking.Charge pairing and hydrogen bonding with cell surface counterparts have been proposed, but their exact role remains putative.The impact of the number and spatial relationships of the guanidinium groups on delivery and organelle/organ localization is yet to be established.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry and ‡Department of Cellular and Molecular Medicine, University of California , San Diego 9500 Gilman Dr., La Jolla, California 92093, United States.

ABSTRACT
Guanidinium-rich scaffolds facilitate cellular translocation and delivery of bioactive cargos through biological barriers. Although impressive uptake has been demonstrated for nonoligomeric and nonpept(o)idic guanidinylated scaffolds in cell cultures and animal models, the fundamental understanding of these processes is lacking. Charge pairing and hydrogen bonding with cell surface counterparts have been proposed, but their exact role remains putative. The impact of the number and spatial relationships of the guanidinium groups on delivery and organelle/organ localization is yet to be established.

Show MeSH