Effects of fasting on liver glycogen structure in rats with type 2 diabetes

Liang Wang; Qinghua Liu; Mengmeng Wang; Yan Du; Xinle Tan; Bingju Xu; Ut Cheung; Enpeng Li; Robert G Gilbert; Daoquan Tang

doi:10.1016/j.carbpol.2020.116144

Effects of fasting on liver glycogen structure in rats with type 2 diabetes

Carbohydr Polym. 2020 Jun 1:237:116144. doi: 10.1016/j.carbpol.2020.116144. Epub 2020 Mar 9.

Authors

Liang Wang¹, Qinghua Liu², Mengmeng Wang², Yan Du², Xinle Tan³, Bingju Xu², Ut Cheung⁴, Enpeng Li⁵, Robert G Gilbert⁶, Daoquan Tang²

Affiliations

¹ Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou 221000, Jiangsu Province, China; Department of Bioinformatics, School of Medical Informatics and Engineering, Xuzhou Medical University, Xuzhou 221000, Jiangsu Province, China.
² Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou 221000, Jiangsu Province, China; Department of Pharmaceutical Analysis, School of Pharmacy, Xuzhou Medical University, Xuzhou 221000, Jiangsu Province, China.
³ School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Queensland 4072, Australia.
⁴ School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia.
⁵ Joint International Research Laboratory of Agriculture and Agri-Product Safety, College of Agriculture, Yangzhou University, Yangzhou 225009, Jiangsu Province, China.
⁶ School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland 4072, Australia; Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Queensland 4072, Australia; Joint International Research Laboratory of Agriculture and Agri-Product Safety, College of Agriculture, Yangzhou University, Yangzhou 225009, Jiangsu Province, China. Electronic address: [email protected].

PMID: 32241436
DOI: 10.1016/j.carbpol.2020.116144

Abstract

Liver glycogen, a highly branched glucose polymer, is important for blood sugar homeostasis. It comprises α particles which are made of linked β particles; the molecular structure changes diurnally. In diabetic liver, the α particles are fragile, easily breaking apart into β particles in chaotropic agents such as dimethyl sulfoxide. We here use size-exclusion chromatography to study how fasting changes liver-glycogen structure in vivo for mice in which type-2 diabetes had previously been induced. Diabetic glycogen degraded enzymatically more quickly in the fasted animals than did glycogen without fasting, with fewer α particles, which however were still fragile. The glycogen had fewer long chains and more shorter chains after fasting. This study gives an overview of the in vivo dynamic changes in α-particles under starvation conditions in both normal and diabetic livers.

Keywords: Diabetes; Dimethyl sulfoxide; Glucose; Glycogen; Molecular structure; Size exclusion chromatography; Streptozotocin.

MeSH terms

Animals
Chromatography, Gel
Diabetes Mellitus, Experimental / metabolism*
Diabetes Mellitus, Type 2 / metabolism*
Fasting*
Liver Glycogen / chemistry*
Liver Glycogen / metabolism
Male
Rats, Sprague-Dawley

Substances

Liver Glycogen