Generation of a DAPK1 knockout first (conditional ready) human embryonic stem cell line (ZSSYe001-A) by CRISPR-Cas9 technology

Death-Associated Protein Kinase 1 (DAPK1) Protects against Myocardial Injury Induced by Myocardial Infarction in Rats via Inhibition of Inflammation and Oxidative Stress

Objective

Heart failure and ventricular remodeling after acute myocardial infarction (AMI) are important factors affecting the prognosis of patients. Therefore, we expected to explore the therapeutic target of AMI by studying the effect of death-associated protein kinase 1 (DAPK1) on AMI rat model.

Materials and Methods

We used male Sprague-Dawley rats to make AMI model, and after 1, 3, 7, and 14 d, we detect the success rate of modeling and the expression change of DAPK1 through 2, 3, 5-triphenyl tetrazolium chloride staining, myocardial injury markers detection, echocardiographic detection, and histological experiment. In addition, we determined the effect of DAPK1 on AMI by subcutaneous injection of the DAPK1 inhibitor (TC-DAPK 6). The effect of DAPK1 on cardiomyocytes has also been verified in cell experiments on H9c2 cells.

Results

The expression of DAPK1 in AMI rats was significantly higher than that in sham group, and it increased with time. The expression of inflammatory factors (interleukin- (IL-) 1β, IL-6, and tumor necrosis factor-α) in AMI rats treated by TC-DAPK 6 was reduced. In addition, TC-DAPK 6 also reduced the activity of malonaldehyde and increased the activities of superoxide dismutase, glutathione, and catalase. The expression of antioxidant molecules such as peroxiredoxin1/4 and glutathione peroxidase1/3 was also promoted by TC-DAPK 6. In H9c2 cells, TC-DAPK 6 also reduced its oxidative stress level.

Conclusions

The increase of DAPK1 may be related to the pathogenesis of AMI. DAPK1 inhibitors protect cardiomyocytes from AMI-induced myocardial injury by reducing levels of inflammation and oxidative stress in myocardial tissue and cells.

CRISPR/Cas gene therapy

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated enzyme (Cas) is a naturally occurring genome editing tool adopted from the prokaryotic adaptive immune defense system. Currently, CRISPR/Cas9-based genome editing has been becoming one of the most promising tools for treating human genetic diseases, including cardiovascular diseases, neuro-disorders, and cancers. As the quick modification of the CRISPR/Cas9 system, including delivery system, CRISPR/Cas9-based gene therapy has been extensively studied in preclinic and clinic treatments. CRISPR/Cas genome editing is also a robust tool to create animal genetic models for studying and treating human genetic disorders, particularly diseases associated with point mutations. However, significant challenges also remain before CRISPR/Cas technology can be routinely employed in the clinic for treating different genetic diseases, which include toxicity and immune response of treated cells to CRISPR/Cas component, highly throughput delivery method, and potential off-target impact. The off-target effect is one of the major concerns for CRISPR/Cas9 gene therapy, more research should be focused on limiting this impact by designing high specific gRNAs and using high specificity of Cas enzymes. Modifying the CRISPR/Cas9 delivery method not only targets a specific tissue/cell but also potentially limits the off-target impact.