TY - JOUR
T1 - Characterization of the Metabolic Flux and Apoptotic Effects of O-Hydroxyl- and N-Acyl-modified N-Acetylmannosamine Analogs in Jurkat Cells
AU - Kim, Eun Jeong
AU - Sampathkumar, Srinivasa Gopalan
AU - Jones, Mark B.
AU - Rhee, Jun Kyu
AU - Baskaran, Gautam
AU - Goon, Scarlett
AU - Yarema, Kevin J.
PY - 2004/4/30
Y1 - 2004/4/30
N2 - The supplementation of the sialic acid biosynthetic pathway with exogenously supplied N-acetylmannosamine (ManNAc) analogs has many potential biomedical and biotechnological applications. In this work, we explore the structure-activity relationship of ManNAc analogs on cell viability and metabolic flux into the sialic acid biosynthetic pathway to gain a better understanding of the fundamental biology underlying "glycosylation engineering" technology. A panel of ManNAc analogs bearing various modifications on the hydroxyl groups as well as substitutions at the N-acyl position was investigated. Increasing the carbon chain length of ester derivatives attached to the hydroxyl groups increased the metabolic efficiency of sialic acid production, whereas similar modification to the N-acyl group decreased efficiency. In both cases, increases in chain length decreased cell viability; DNA ladder formation, Annexin V-FITC two-dimensional flow cytometry assays, caspase-3 activation, and down-regulation of sialoglycoconjugate-processing enzymes established that the observed growth inhibition and toxicity resulted from apoptosis. Two of the panel of 12 analogs tested, specifically Ac4ManNLev and Ac4ManNHomoLev, were highly toxic. Interestingly, both of these analogs maintained a ketone functionality in the same position relative to the core monosaccharide structure, and both also inhibited flux through the sialic acid pathway (the remainder of the less toxic analogs either increased or had no measurable impact on flux). These results provide fundamental insights into the role of sialic acid metabolism in apoptosis by demonstrating that ManNAc analogs can modulate apoptosis both indirectly via hydroxyl-group effects and directly through N-acyl-group effects.
AB - The supplementation of the sialic acid biosynthetic pathway with exogenously supplied N-acetylmannosamine (ManNAc) analogs has many potential biomedical and biotechnological applications. In this work, we explore the structure-activity relationship of ManNAc analogs on cell viability and metabolic flux into the sialic acid biosynthetic pathway to gain a better understanding of the fundamental biology underlying "glycosylation engineering" technology. A panel of ManNAc analogs bearing various modifications on the hydroxyl groups as well as substitutions at the N-acyl position was investigated. Increasing the carbon chain length of ester derivatives attached to the hydroxyl groups increased the metabolic efficiency of sialic acid production, whereas similar modification to the N-acyl group decreased efficiency. In both cases, increases in chain length decreased cell viability; DNA ladder formation, Annexin V-FITC two-dimensional flow cytometry assays, caspase-3 activation, and down-regulation of sialoglycoconjugate-processing enzymes established that the observed growth inhibition and toxicity resulted from apoptosis. Two of the panel of 12 analogs tested, specifically Ac4ManNLev and Ac4ManNHomoLev, were highly toxic. Interestingly, both of these analogs maintained a ketone functionality in the same position relative to the core monosaccharide structure, and both also inhibited flux through the sialic acid pathway (the remainder of the less toxic analogs either increased or had no measurable impact on flux). These results provide fundamental insights into the role of sialic acid metabolism in apoptosis by demonstrating that ManNAc analogs can modulate apoptosis both indirectly via hydroxyl-group effects and directly through N-acyl-group effects.
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U2 - 10.1074/jbc.M400205200
DO - 10.1074/jbc.M400205200
M3 - Article
C2 - 14966124
AN - SCOPUS:2442517499
SN - 0021-9258
VL - 279
SP - 18342
EP - 18352
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 18
ER -