The circRNA-mediated ceRNA molecular regulatory network in fatigue-type type 2 diabete.

Fatigue is a common but poorly understood issue in type 2 diabetes (T2DM) that affects quality of life. Although ceRNA networks regulate disease progression, their role in T2DM-related fatigue (F-T2DM) is unclear. This study developed a circRNA-mediated ceRNA network to uncover the molecular interactions causing fatigue in F-T2DM. The study included healthy control group (Control, n = 21), F-T2DM group (n = 21), and non-fatigue type 2 diabetes patients (NF-T2DM, n = 21). By combining high-throughput sequencing to screen differentially expressed circRNAs (F-T2DM vs Control: 1144; F-T2DM vs NF-T2DM: 1303) and mRNAs (F-T2DM vs Control: 912; F-T2DM vs NF-T2DM: 1190), it was found that hsa_circ_0078539 and hsa_circ_0026239 were significantly upregulated in F-T2DM compared to both Control and NF-T2DM groups, and their host genes were involved in cytoskeleton remodeling. The GO/KEGG enrichment analysis combined with weighted gene co-expression network (WGCNA) of F-T2DM compared with Control indicated that the core pathways of F-T2DM focused on actin cytoskeleton dynamic regulation, AMPK signaling pathway, tricarboxylic acid cycle, and oxidative stress response. In the enrichment analysis of F-T2DM and NF-T2DM, cytoskeleton dynamics regulation, AMPK signaling pathway, and tricarboxylic acid cycle were further enriched, and the specific activation of reactive oxygen metabolism balance and AGE-RAGE pathway was also observed. Further, through multi-database prediction and experimental verification, a F-T2DM-specific ceRNA network was constructed, and key regulatory axes hsa_circ_0044623/hsa-mir-129-5p/MYLK3, hsa_circ_0002622/hsa-mir-200b-3p/RAB21, and hsa_circ_0078539/hsa-mir-4695-3p/SLC7A14 were screened out. The ceRNA regulatory network in human and animal samples was confirmed using RT-qPCR. These axes drive the pathological process by regulating myocardial contractility efficiency, glucose transport, mitochondrial energy metabolism, and insulin signaling pathway. This study clarified the molecular regulatory mode of patients with fatigue type 2 diabetes from the perspective of ceRNA network, providing a new direction for the research on diabetes classification and diagnosis.