The role of N-glycosylation in high glucose-induced upregulation of intercellular adhesion molecule-1 on bovine retinal endothelial cells.

Abstract

PURPOSE:

The development of diabetic retinopathy has been implicated as a consequence of chronic inflammation. Given the role of the intercellular adhesion molecule-1 (ICAM-1) in inflammation, the potential effect of N-glycosylation on the upregulated expression of ICAM-1 at the surface of bovine retinal endothelial cells (BRECs) induced by high glucose concentrations was investigated.

METHODS:

Gene and protein expression of ICAM-1 in primary BRECs cultured in medium containing increasing concentrations of mannose or glucose in the presence or absence of tunicamycin were studied with reverse transcription-polymerase chain reaction and Western blot analysis, and the expression level of ICAM-1 at the surface of BRECs was examined with an immunofluorescence analysis. A lectin blot assay with PHA-L was performed to explore the level of N-glycans on cell total proteins or immunoprecipitated ICAM-1 from cells treated or untreated with high glucose.

RESULTS:

Both the mRNA and protein levels of ICAM-1, as well as the level of ICAM-1 on the cell surface, were significantly upregulated by increasing the concentration of glucose in the culture medium, with a peak concentration of 20 mm. Consistent with these results, a dramatic increase in the N-glycosylation of ICAM-1 in BRECs cultured with a high concentration of glucose was observed, which could be partially attenuated by tunicamycin treatment.

CONCLUSION:

High glucose-induced upregulation of ICAM-1 on the surface of BRECs could be ascribed to the alterations in its N-glycosylation at least in part, indicating that interference with the glycosylation of ICAM-1 may contribute to improving the efficiency of current therapies with diabetic retinopathy.

• Authors: Kun Liu, Haiyun Liu, Zhihua Zhang, Wen Ye, Xun Xu
• Journal: Acta ophthalmologica (Acta Ophthalmol) Vol. 94 Issue 4 Pg. 353-7 (Jun 2016) ISSN: 1755-3768 [Electronic] England
• PMID: 27151646 (Publication Type: Journal Article)
• Copyright: © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Chemical References

• Polysaccharides
• RNA, Messenger
• Intercellular Adhesion Molecule-1
• Glucose

Topics

• Animals
• Blotting, Western
• Cattle
• Cells, Cultured
• Endothelium, Vascular (drug effects, metabolism)
• Flow Cytometry
• Fluorescent Antibody Technique, Indirect
• Glucose (pharmacology)
• Glycosylation
• Intercellular Adhesion Molecule-1 (genetics, metabolism)
• Polysaccharides (metabolism)
• RNA, Messenger (genetics)
• Real-Time Polymerase Chain Reaction
• Retinal Vessels (cytology)
• Up-Regulation