Genetic characterization of dilated cardiomyopathy patients undergoing heart transplantation in the Chinese population by whole-exome sequencing

BMP6, a potential biomarker of inflammatory fibrosis and promising protective factor for dilated cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) stands as one of the most prevalent and severe causes of heart failure. Inflammation plays a pivotal role throughout the progression of DCM to heart failure, while age acts as a natural predisposing factor for all cardiovascular diseases. These two factors often interact, contributing to cardiac fibrosis, which is both a common manifestation and a pathogenic driver of adverse remodeling in DCM-induced heart failure.

METHOD

Bulk RNA-seq, single-cell RNA-seq, Mendelian randomization analysis, animal model construction, and BMP6 knockdown were utilized to identify and validate potential specific markers and targets for intervention in DCM heart failure.

RESULTS

We found that DCM hearts exhibit pronounced inflammatory cell infiltration and fibrosis. Both bulk RNA-seq and single-cell RNA-seq analyses revealed aberrant BMP6 expression specifically in fibroblasts. The ROC curve underscores the high specificity of BMP6 in relation to DCM, while Mendelian randomization analysis further confirms BMP6 as a protective factor against DCM. Notably, BMP6 knockdown led to a decrease in SMAD6 expression and a marked elevation in COL1A1 expression levels, indicating its antifibrotic role.

CONCLUSION

BMP6 emerges as a promising biomarker for DCM, and its functional role in exerting an antifibrotic effect underscores its potential as a therapeutic target.

Cas13b-mediated RNA targeted therapy alleviates genetic dilated cardiomyopathy in mice

BACKGROUND

Recent advances in gene editing technology have opened up new avenues for in vivo gene therapy, which holds great promise as a potential treatment method for dilated cardiomyopathy (DCM). The CRISPR-Cas13 system has been shown to be an effective tool for knocking down RNA expression in mammalian cells. PspCas13b, a type VI-B effector that can be packed into adeno-associated viruses and improve RNA knockdown efficiency, is a potential treatment for diseases characterized by abnormal gene expression.

RESULTS

Using PspCas13b, we were able to efficiently and specifically knockdown the mutant transcripts in the AC16 cell line carrying the heterozygous human TNNT2R141W (hTNNT2R141W) mutation. We used adeno-associated virus vector serotype 9 to deliver PspCas13b with specific single guide RNA into the hTNNT2R141W transgenic DCM mouse model, effectively knocking down hTNNT2R141W transcript expression. PspCas13b-mediated knockdown significantly increased myofilament sensitivity to Ca2+, improved cardiac function, and reduced myocardial fibrosis in hTNNT2R141W DCM mice.

CONCLUSIONS

These findings suggest that targeting genes through Cas13b is a promising approach for in vivo gene therapy for genetic diseases caused by aberrant gene expression. Our study provides further evidence of Cas13b's application in genetic disease therapy and paves the way for future applicability of genetic therapies for cardiomyopathy.