Biologie Cellulaire et Moléculaire

Abstrait

Cation-dependent Mannose 6-Phosphate Receptor Functions as a Key Regulator of Palmitic Acid-induced Cell Death in Cardiomyocytes

Qiaoli Zeng1,3,4, Xiaoyi Xu2,4, Taili Yang3,6, Hengli Zhang3,6,Taotao Shao3,6, Bing Tan3,5, Zhaoshou Yang5 * and Runmin Guo1,3,6

Background: Palmitic acid (PA), a common saturated free fatty acid, is known as inducer of apoptosis in numerous cell types. M6PR-CD has been reported as a potential pro-apoptotic factor in several models. Objective: We aim to identify the critical regulatory molecules in the process of palmitate-induced apoptosis in H9C2 cardiomyocytes. Methods: Cells treated with 250 μM PA for 24 hours were collected. Transcriptome sequencing and bioinformatics analysis were carried out to screen the differentially expressed genes. RT-PCR and western blot were used to confirm the up-regulation of M6PR-CD. The function of M6PR-CD was studied through the detection of cell viability, apoptosis and intracellular ROS levels. Results: A total of 1025 differentially expressed genes were screened by transcriptome sequencing, including 718 up-regulated genes and 307 down-regulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were mainly focused on the apoptotic and stress. M6PR-CD was significantly upregulated with PA treatment. Knockdown of M6PR-CD alleviated the PA-induced apoptosis with lower ROS levels. After transfection with M6PR-CD siRNA, it was also found that compensatory increase in M6PR-CI subtype did not exist, and the expression of caspase-3 was almost the same. Conclusion: This study identified a number of genes related to PA-induced cardiomyocytes apoptosis through transcriptome sequencing. It was clarified for the first time that M6PR-CD could induce H9C2 cardiomyocytes apoptosis by enhancing ROS production rather than being Caspase-3-dependent, providing a theoretic basis for us to have a better understanding of the intrinsic mechanism.