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To clarify the role of TRAF3IP2 in high glucose (HG)‐stimulated cardiomyocyte inflammation and apoptosis and its action mechanism. SiRNA plasmid of TRAF3IP2 was constructed and transfected into HG‐stimulated cardiomyocytes to silence TRAF3IP2. The expression of TRAF3IP2 was determined by quantitative polymerase chain reaction (qPCR) and western blot. Cell viability and cytotoxicity were first observed using cell counting kit‐8 and lactate dehydrogenase assays. The inflammatory injury of the cardiomyocytes was then examined by real time‐qPCR (RT‐qPCR) and western blot. The oxidative stress of the cardiomyocytes was evaluated using reactive oxygen species assay kit, RT‐qPCR, western blot and enzyme activity assay kit. Next, cell apoptosis was detected employing TUNEL and western blot. Finally, RT‐qPCR and western blot were performed to investigate the effects of inhibitors of dipeptidyl peptidase‐4, including saxagliptin, empagliflozin and linagliptin, on TRAF3IP2. TRAF3IP2 expression was found to be increased in HG‐stimulated cardiomyocytes. TRAF3IP2 interference inhibited HG‐induced cell viability loss, cytotoxicity, inflammatory response, oxidative stress and apoptosis of the cardiomyocytes. Moreover, saxagliptin, empagliflozin and linagliptin inhibited the expression of TRAF3IP2. TRAF3IP2 interference alleviates HG‐induced inflammation and apoptosis of cardiomyocytes. The result suggests that TRAF3IP2 may be a promising therapeutic target in treating diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to investigate the electrophysiological characteristics and long-term outcome of patients undergoing substrate-based ablation of left posterior fascicular ventricular tachycardia (LPF-VT) guided by targeting of fragmented antegrade Purkinje potentials (FAPs) during sinus rhythm., Methods and Results: This study retrospectively analysed 50 consecutive patients referred for ablation. Substrate mapping during sinus rhythm was performed to identify the FAP that was targeted by ablation. FAPs were recorded in 48 of 50 (96%) patients during sinus rhythm. The distribution of FAPs was located at the proximal segment of posterior septal left ventricle (LV) in two (4.2%) patients, middle segment in 33 (68.8%) patients, and distal segment in 13 (27.1%) patients. In 32 of 48 (66.7%) patients, the FAP displayed a continuous multicomponent fragmented electrogram, while a fragmented, split, and uncoupled electrogram was recorded in 16 (33.3%) patients. Entrainment attempts at FAP region were performed successfully in seven patients, demonstrating concealed fusion and the critical isthmus of LPF-VT. Catheter ablation targeting at the FAPs successfully terminated the LPF-VT in all 48 patients in whom they were seen. Left posterior fascicular (LPF) block occurred in four (8%) patients after ablation. During a median follow-up period of 61.2 ± 16.8 months, 47 of 50 (94%) patients remained free from recurrent LPF-VT., Conclusion: Ablation of LPF-VT targeting FAP during sinus rhythm results in excellent long-term clinical outcome. FAPs were commonly located at the middle segment of posterior septal LV. Region with FAPs during sinus rhythm was predictive of critical site for re-entry., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)