TY - JOUR
T1 - Sensitive quantification of a-glucans in mouse tissues, cell cultures, and human cerebrospinal fluid
AU - Nitschke, Silvia
AU - Petkovic, Sara
AU - Ahonen, Saija
AU - Minassian, Berge A.
AU - Nitschke, Felix
N1 - Publisher Copyright:
© 2020 Nitschke et al. Published under exclusive license by The American Society for Biochemistry and Molecular Biology, Inc.
PY - 2020/10/23
Y1 - 2020/10/23
N2 - The soluble a-polyglucan glycogen is a central metabolite enabling transient glucose storage to suit cellular energy needs. Glycogen storage diseases (GSDs) comprise over 15 entities caused by generalized or tissue-specific defects in enzymes of glycogen metabolism. In several, e.g. in Lafora disease caused by the absence of the glycogen phosphatase laforin or its interacting partner malin, degradation-resistant abnormally structured insoluble glycogen accumulates. Sensitive quantification methods for soluble and insoluble glycogen are critical to research, including therapeutic studies, in such diseases. This paper establishes methodological advancements relevant to glycogen metabolism investigations generally, and GSDs. Introducing a pre-extraction incubation method, we measure degradation-resistant glycogen in as little as 30 mg of skeletal muscle or a single hippocampus from Lafora disease mouse models. The digestion-resistant glycogen correlates with the disease-pathogenic insoluble glycogen and can readily be detected in very young mice where glycogen accumulation has just begun. Second, we establish a high-sensitivity glucose assay with detection of ATP depletion, enabling 1) quantification of a-glucans in cell culture using a medium-throughput assay suitable for assessment of candidate glycogen synthesis inhibitors, and 2) discovery of a-glucan material in healthy human cerebrospinal fluid, establishing a novel methodological platform for biomarker analyses in Lafora disease and other GSDs.
AB - The soluble a-polyglucan glycogen is a central metabolite enabling transient glucose storage to suit cellular energy needs. Glycogen storage diseases (GSDs) comprise over 15 entities caused by generalized or tissue-specific defects in enzymes of glycogen metabolism. In several, e.g. in Lafora disease caused by the absence of the glycogen phosphatase laforin or its interacting partner malin, degradation-resistant abnormally structured insoluble glycogen accumulates. Sensitive quantification methods for soluble and insoluble glycogen are critical to research, including therapeutic studies, in such diseases. This paper establishes methodological advancements relevant to glycogen metabolism investigations generally, and GSDs. Introducing a pre-extraction incubation method, we measure degradation-resistant glycogen in as little as 30 mg of skeletal muscle or a single hippocampus from Lafora disease mouse models. The digestion-resistant glycogen correlates with the disease-pathogenic insoluble glycogen and can readily be detected in very young mice where glycogen accumulation has just begun. Second, we establish a high-sensitivity glucose assay with detection of ATP depletion, enabling 1) quantification of a-glucans in cell culture using a medium-throughput assay suitable for assessment of candidate glycogen synthesis inhibitors, and 2) discovery of a-glucan material in healthy human cerebrospinal fluid, establishing a novel methodological platform for biomarker analyses in Lafora disease and other GSDs.
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U2 - 10.1074/jbc.RA120.015061
DO - 10.1074/jbc.RA120.015061
M3 - Article
C2 - 32817315
AN - SCOPUS:85094684967
SN - 0021-9258
VL - 295
SP - 14698
EP - 14709
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 43
ER -