Abstract 14197: C14a Mutation Abolishes Mg53-Aggravated Glucose Metabolic Dysfunction and Exerts a Dominant Therapeutic Target for Ischemia and Reperfusion (i/r) Injury in Diabetic Heart

Autor: Han Feng, Shuo Zhang, Xinli Hu, Gengjia Chen, Hong-Kun Wu, Rui-Ping Xiao, Matthew J Robeson, Hao Shen, Fengxiang Lv, Yan Zhang
Rok vydání: 2020
Předmět:
Zdroj: Circulation. 142
ISSN: 1524-4539
0009-7322
DOI: 10.1161/circ.142.suppl_3.14197
Popis: Introduction: MG53, essential for cardiac ischemic protection, negatively regulates insulin receptor (IR) to trigger globular metabolic dysfunction, which makes up a big obstacle for its clinical use. In vitro evidence shows that C14A site of MG53 might be a promising target both to abolish MG53 regulation on IR and to keep as much protective function. However, in vivo effect on C14A mutation of MG53 is urgent to be explored. Results: Here, we found C14A knock-in mice exerted relieved insulin resistance, blood glucose, and metabolic phenotype in high fat diet-induced pre-diabetic model. C14A mutation did NOT lessen the protective effect of MG53 by either intracellular knock-in or extracellular addition of mutant protein against ischemia/reperfusion(I/R) injury in db/+ mice. Consistent with our previous study, we found that administration of MG53 on diabetic mice showed aggravated blood glucose, insulin resistance, and unstable cardiac function to induce a higher risk under I/R attack. C14A mutation reduced the affinity between IR ECD and MG53 to block recombinant human (rh) MG53-WT-triggered acute hyperglycemia, increased heart infarct area and death rate on db/db mice during I/R injury. Post-conditioning of rhMG53-C14A stabilized intra-operative blood glucose and showed stronger anti-I/R ability than MG53-WT protein on db/db mice. Conclusions: C14A mutation is a potential target for MG53 treatment on diabetic heart. This potential therapeutic approach for the treatment of patients within type 2 diabetes provides a strategy of gene engineering optimizing well-known target to draw on advantages and avoid pitfalls.
Databáze: OpenAIRE