Diurnal changes of glycogen molecular structure in healthy and diabetic mice

Zhenxia Hu; Bin Deng; Xinle Tan; Hua Gan; Cheng Li; Sharif S Nada; Mitchell A Sullivan; Jialun Li; Xiaoyin Jiang; Enpeng Li; Robert G Gilbert

doi:10.1016/j.carbpol.2018.01.003

Diurnal changes of glycogen molecular structure in healthy and diabetic mice

Carbohydr Polym. 2018 Apr 1:185:145-152. doi: 10.1016/j.carbpol.2018.01.003. Epub 2018 Jan 3.

Authors

Zhenxia Hu¹, Bin Deng², Xinle Tan³, Hua Gan⁴, Cheng Li⁵, Sharif S Nada⁶, Mitchell A Sullivan⁷, Jialun Li⁸, Xiaoyin Jiang⁴, Enpeng Li⁵, Robert G Gilbert⁹

Affiliations

¹ Department of Pharmacy, Renmin Hospital of Wuhan University, Wuhan, Hubei 430030, China.
² Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China. Electronic address: [email protected].
³ School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, 4072, Australia.
⁴ School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
⁵ Joint International Research Laboratory of Agriculture and Agri-Product Safety, College of Agriculture, Yangzhou University, Yangzhou 225009, Jiangsu Province, China.
⁶ The University of Queensland, Centre for Nutrition and Food Science, Queensland Alliance for Agriculture and Food Innovation, Brisbane, QLD 4072, Australia.
⁷ Glycation and Diabetes, Mater Research Institute, Translational Research Institute, The University of Queensland, Brisbane, QLD 4102, Australia.
⁸ Department of Plastic Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
⁹ Joint International Research Laboratory of Agriculture and Agri-Product Safety, College of Agriculture, Yangzhou University, Yangzhou 225009, Jiangsu Province, China; School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China; The University of Queensland, Centre for Nutrition and Food Science, Queensland Alliance for Agriculture and Food Innovation, Brisbane, QLD 4072, Australia.

PMID: 29421051
DOI: 10.1016/j.carbpol.2018.01.003

Abstract

Glycogen is a complex branched glucose polymer functioning as a blood-sugar reservoir in animals. Liver glycogen β particles can bind together to form α particles, which have a slower enzymatic degradation to glucose. The linkage between β particles in α particles in diabetic liver breaks (is fragile) in dimethyl sulfoxide (DMSO), a H-bond disruptor, consistent with blood-sugar homeostasis loss in diabetes. We examined diurnal changes in the molecular structure of healthy and diabetic mouse-liver glycogen. Healthy mouse glycogen was fragile to DMSO during glycogen synthesis but not degradation; diabetic glycogen was always fragile. Two alternative mechanisms for this are suggested: healthy glycogen is fragile when formed and becomes stable during subsequent degradation, a process damaged in diabetes; alternatively, there are two types of glycogen: one compact but fragile and the other loose but non-fragile. This suggests potential types of diabetes drug targets through modifying the activities of glycogen synthesis enzymes.

Keywords: Characterization; Diabetes; GPC; Glycogen; Molecular structure.

MeSH terms

Animals
Circadian Clocks*
Diabetes Mellitus, Experimental / genetics
Diabetes Mellitus, Experimental / metabolism*
Glycogen / chemistry
Glycogen / metabolism*
Liver / metabolism*
Male
Mice
Mice, Inbred C57BL

Substances

Glycogen