Transcriptomic Mechanism Of Impaired Autophagy Flow Induced By Myocardial Ischemia-reperfusion Injury In Diabetes Mellitus

Objective: Single cell transcriptomic sequencing technology was used to mine data on the integrity of myocardial autophagy flow after ischemia reperfusion in diabetic myocardium in order to find potential therapeutic targets for diabetic myocardial vulnerability.Method: One adult male mouse in the normal group(NM),the normal ischemia reperfusion group(NMI),the diabetic group(DM)and the diabetic ischemia reperfusion group(DMI)was killed,and the heart tissue was collected and prepared into cell suspension for machine sequencing.GO and KEGG enrichment analysis was used to carry out in-depth data mining on the changes of 218 Autophagy related genes(186 genes were from Human Autophagy Database,and 32 autophagy related genes were obtained by consulting high-quality literature)among the four groups of samples.Results: We found that the number of myocyte subsets changed most significantly among the four groups of samples,and the average expression of 218 autophagy related genes changed most significantly in myocytes.Compared with the normal group(NM),the expression of autophagy related genes in myocyte subsets of diabetes group(DM)was significantly up-regulated(P < 0.05).GO and KEGG enriched and analyzed 14 autophagy related genes involved in autophagosomal and lysosomal directed transport.The enrichment results showed that the processes of "lysosomal localization","organelle transport along microtubules" and "anteroonal synaptic vesicular transport" were enriched.Compared with the normal ischemia reperfusion group VS the normal group(NMI/NM),RILP was most significantly down-regulated in DM VS DM group(FC = 1.11 in NMI/NM group and FC = 0.37 in DMI/DM group).The 31 autophagosome and lysosome fusion related genes selected by GO and KEGG enrichment analysis showed significant enrichment during "autophagosome maturation","lysosome pathway","HOPS complex","autophagosome and lysosome fusion" and other processes.Compared with normal ischemia-reperfusion group VS normal group(NMI/NM),MON1 A was most significantly down-regulated in diabetic ischemia-reperfusion group VS diabetic group(DMI/DM)(FC= 1.28 in NMI/NM group,FC = 0.34 in DMI/DM group).Conclusions: Combined with single-cell sequencing results,myocardial cells were more susceptible to autophagy than endothelial cells and fibroblasts,and the number of myocardial cells changed significantly than endothelial cells and fibroblasts.Secondly,the expression of RILP,as an important regulatory gene of autophagosome transport,is significantly down-regulated after ischemia reperfusion in diabetes.Meanwhile,the expression of MON1 A,a gene involved in the fusion of autophagosome and lysosome,is also significantly down-regulated after ischemia reperfusion in diabetes,which may be the key reason for the impaired integrity of autophagic flow and increased myocardial vulnerability.