Hydrophobic Man-1-P derivatives correct abnormal glycosylation in Type I congenital disorder of glycosylation fibroblasts
(2005) In Glycobiology 15(11). p.93-1084- Abstract
Patients with Type I congenital disorders of glycosylation (CDG-I) make incomplete lipid-linked oligosaccharides (LLO). These glycans are poorly transferred to proteins resulting in unoccupied glycosylation sequons. Mutations in phosphomannomutase (PMM2) cause CDG-Ia by reducing the activity of PMM, which converts mannose (Man)-6-P to Man-1-P before formation of GDP-Man. These patients have reduced Man-1-P and GDP-Man. To replenish intracellular Man-1-P pools in CDG-Ia cells, we synthesized two hydrophobic, membrane permeable acylated versions of Man-1-P and determined their ability to normalize LLO size and N-glycosylation in CDG-Ia fibroblasts. Both compounds, compound I (diacetoxymethyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl... (More)
Patients with Type I congenital disorders of glycosylation (CDG-I) make incomplete lipid-linked oligosaccharides (LLO). These glycans are poorly transferred to proteins resulting in unoccupied glycosylation sequons. Mutations in phosphomannomutase (PMM2) cause CDG-Ia by reducing the activity of PMM, which converts mannose (Man)-6-P to Man-1-P before formation of GDP-Man. These patients have reduced Man-1-P and GDP-Man. To replenish intracellular Man-1-P pools in CDG-Ia cells, we synthesized two hydrophobic, membrane permeable acylated versions of Man-1-P and determined their ability to normalize LLO size and N-glycosylation in CDG-Ia fibroblasts. Both compounds, compound I (diacetoxymethyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl phosphate) (C-I) and compound II (diacetoxymethyl 2,3,4,6-tetra-O-ethyloxycarbonyl-alpha-D-mannopyranosyl phosphate) (C-II), contain two acetoxymethyl (CH2OAc) groups O-linked to phosphorous. C-I contains acetyl esters and C-II contains ethylcarbonate (CO2Et) esters on the Man residue. Both C-I and C-II normalized truncated LLO, but C-II was about 2-fold more efficient than C-I. C-II replenished the GDP-Man pool in CDG-Ia cells and was more efficiently incorporated into glycoproteins than exogenous Man at low concentrations (25-75 mM). In a glycosylation assay of DNaseI in CDG-Ia cells, C-II restored glycosylation to control cell levels. C-II also corrected impaired LLO biosynthesis in cells from a Dolichol (Dol)-P-Man deficient patient (CDG-Ie) and partially corrected LLO in cells from an ALG12 mannosyltransferase-deficient patient (CDG-Ig), whereas cells from an ALG3-deficient patient (CDG-Id) and from an MPDU1-deficient patient (CDG-If) were not corrected. These results validate the general concept of using pro-Man-1-P substrates as potential therapeutics for CDG-I patients.
(Less)
- author
- Eklund, Erik A LU ; Merbouh, Nabyl ; Ichikawa, Mie ; Nishikawa, Atsushi ; Clima, Jessica M ; Dorman, James A ; Norberg, Thomas and Freeze, Hudson H
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- keywords
- Carbohydrate Conformation, Carbohydrate Metabolism, Cell Proliferation/drug effects, Congenital Disorders of Glycosylation/metabolism, Culture Media/chemistry, Dose-Response Relationship, Drug, Fibroblasts/chemistry, Glycosylation/drug effects, Humans, Mannosephosphates/chemical synthesis, Mutation, Phosphotransferases (Phosphomutases)/genetics, Sugar Phosphates/chemical synthesis, Time Factors
- in
- Glycobiology
- volume
- 15
- issue
- 11
- pages
- 93 - 1084
- publisher
- Oxford University Press
- external identifiers
-
- scopus:27944497414
- pmid:16079417
- ISSN
- 0959-6658
- DOI
- 10.1093/glycob/cwj006
- language
- English
- LU publication?
- no
- id
- b56595f7-193f-46c6-8a3c-05002fb882c7
- date added to LUP
- 2021-10-12 00:05:47
- date last changed
- 2024-01-05 17:50:48
@article{b56595f7-193f-46c6-8a3c-05002fb882c7,
abstract = {{<p>Patients with Type I congenital disorders of glycosylation (CDG-I) make incomplete lipid-linked oligosaccharides (LLO). These glycans are poorly transferred to proteins resulting in unoccupied glycosylation sequons. Mutations in phosphomannomutase (PMM2) cause CDG-Ia by reducing the activity of PMM, which converts mannose (Man)-6-P to Man-1-P before formation of GDP-Man. These patients have reduced Man-1-P and GDP-Man. To replenish intracellular Man-1-P pools in CDG-Ia cells, we synthesized two hydrophobic, membrane permeable acylated versions of Man-1-P and determined their ability to normalize LLO size and N-glycosylation in CDG-Ia fibroblasts. Both compounds, compound I (diacetoxymethyl 2,3,4,6-tetra-O-acetyl-alpha-D-mannopyranosyl phosphate) (C-I) and compound II (diacetoxymethyl 2,3,4,6-tetra-O-ethyloxycarbonyl-alpha-D-mannopyranosyl phosphate) (C-II), contain two acetoxymethyl (CH2OAc) groups O-linked to phosphorous. C-I contains acetyl esters and C-II contains ethylcarbonate (CO2Et) esters on the Man residue. Both C-I and C-II normalized truncated LLO, but C-II was about 2-fold more efficient than C-I. C-II replenished the GDP-Man pool in CDG-Ia cells and was more efficiently incorporated into glycoproteins than exogenous Man at low concentrations (25-75 mM). In a glycosylation assay of DNaseI in CDG-Ia cells, C-II restored glycosylation to control cell levels. C-II also corrected impaired LLO biosynthesis in cells from a Dolichol (Dol)-P-Man deficient patient (CDG-Ie) and partially corrected LLO in cells from an ALG12 mannosyltransferase-deficient patient (CDG-Ig), whereas cells from an ALG3-deficient patient (CDG-Id) and from an MPDU1-deficient patient (CDG-If) were not corrected. These results validate the general concept of using pro-Man-1-P substrates as potential therapeutics for CDG-I patients.</p>}},
author = {{Eklund, Erik A and Merbouh, Nabyl and Ichikawa, Mie and Nishikawa, Atsushi and Clima, Jessica M and Dorman, James A and Norberg, Thomas and Freeze, Hudson H}},
issn = {{0959-6658}},
keywords = {{Carbohydrate Conformation; Carbohydrate Metabolism; Cell Proliferation/drug effects; Congenital Disorders of Glycosylation/metabolism; Culture Media/chemistry; Dose-Response Relationship, Drug; Fibroblasts/chemistry; Glycosylation/drug effects; Humans; Mannosephosphates/chemical synthesis; Mutation; Phosphotransferases (Phosphomutases)/genetics; Sugar Phosphates/chemical synthesis; Time Factors}},
language = {{eng}},
number = {{11}},
pages = {{93--1084}},
publisher = {{Oxford University Press}},
series = {{Glycobiology}},
title = {{Hydrophobic Man-1-P derivatives correct abnormal glycosylation in Type I congenital disorder of glycosylation fibroblasts}},
url = {{http://dx.doi.org/10.1093/glycob/cwj006}},
doi = {{10.1093/glycob/cwj006}},
volume = {{15}},
year = {{2005}},
}