Effect of TBK1 overexpression on hypoxia-reoxygenation injury in isolated mouse cardiomyocytes subjected to high glucose: relationship with mitochondrial autophagy / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of TBK1 overexpression on hypoxia-reoxygenation (H/R) injury in isolated mouse cardiomyocytes subjected to high glucose and the relationship with mitochondrial autophagy.Methods:Normally cultured log-phase HL-1 mouse cardiomyocytes were inoculated in a 6-well plate at a density of 1×10 6 cells/ml and were divided into 4 groups ( n=10 each) using a random number table method: control group (group C), high glucose group (group HG), high glucose and H/R group (group HG+ H/R), and TBK1 overexpression group (group TBK1). The cells were incubated in culture medium with 1% fetal bovine serum and 1% double antibody for 24 h when the cell density reached 50%.When the cell density reached 80%, pcDNA3.1 (+ ) was used as a vector to achieve TBK1 overexpression.The cells were cultured with high glucose medium (33 mmol/L) for 24 h, exposed to 94% N 2+ 5% CO 2+ 1% O 2 for 24 h in an incubator at 37℃ followed by 12 h reoxygenation in an incubator containing 5% CO 2 at 37°C to establish the model of H/R injury to cardiomyocytes subjected to high glucose.After reoxygenation, CCK-8 assay was used to detect cell viability, the activity of lactic dehydrogenase (LDH) in supernatant was detected using LDH kit, mitochondrial contents were determined using Mito-Tracter green fluorescent probe, and the expression of TBK1 and mitophagy-related proteins PINK1, Parkin, LC3B and P62 was detected by Western blot. Results:Compared with group C, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in HG group and HG+ H/R group ( P<0.05). Compared with group HG, the cell viability was significantly decreased, the activity of LDH in supernatant was increased, mitochondrial contents were decreased, the expression of TBK1, PINK1, Parkin and LC3B was down-regulated, and the expression of P62 was up-regulated in group HG+ H/R ( P<0.05). Compared with group HG+ H/R, the the cell viability was significantly increased, the activity of LDH in supernatant was decreased, mitochondrial contents were increased, the expression of TBK1, PINK1, Parkin and LC3B was up-regulated, and the expression of P62 was down-regulated in group TBK1 ( P<0.05). Conclusion:The mechanism by which TBK1 overexpression reduces the H/R injury is related to restoring mitophagy in isolated mouse cardiomyocytes subjected to high glucose.