Liver glycogen fragility in the presence of hydrogen-bond breakers

Int J Biol Macromol. 2024 Apr 20;268(Pt 1):131741. doi: 10.1016/j.ijbiomac.2024.131741. Online ahead of print.ABSTRACTGlycogen, a complex branched glucose polymer, is responsible for sugar storage in blood glucose homeostasis. It comprises small β particles bound together into composite α particles. In diabetic livers, α particles are fragile, breaking apart into smaller particles in dimethyl sulfoxide, DMSO; they are however stable in glycogen from healthy animals. We postulate that the bond between β particles in α particles involves hydrogen bonding. Liver-glycogen fragility in normal and db/db mice (an animal model for diabetes) is compared using various hydrogen-bond breakers (DMSO, guanidine and urea) at different temperatures. The results showed different degrees of α-particle disruption. Disrupted glycogen showed changes in the mid-infra-red spectrum that are related to hydrogen bonds. While glycogen α-particles are only fragile under harsh, non-physiological conditions, these results nevertheless imply that the bonding between β particles in α particles is different in diabetic livers compared to healthy, and is probably associated with hydrogen bonding.PMID:38649083 | DOI:10.1016/j.ijbiomac.2024.131741
Source: International Journal of Biological Macromolecules - Category: Biochemistry Authors: Source Type: research