LncRNA CFAR promotes cardiac fibrosis via the miR-449a-5p/LOXL3/mTOR axis

Area of Science:

• Cardiovascular Biology
• Molecular Mechanisms of Disease
• Non-coding RNA Research

Background:

• Cardiac fibrosis is a key pathological process leading to heart failure, but its molecular drivers are not fully understood.
• Identifying novel molecular targets is crucial for developing effective therapies against cardiac fibrosis.

Purpose of the Study:

• To investigate the role of a newly identified long non-coding RNA, cardiac fibrosis-associated regulator (CFAR), in cardiac fibrosis.
• To elucidate the molecular mechanism underlying CFAR's function in cardiac fibrosis.

Main Methods:

• Quantitative real-time PCR to measure gene expression.
• Cell proliferation assays for cardiac fibroblasts.
• RNA immunoprecipitation and luciferase reporter assays to confirm molecular interactions.
• In vivo studies to assess the effect of CFAR and miR-449a-5p on cardiac fibrosis.

Main Results:

• CFAR expression is upregulated in cardiac fibrosis and promotes fibroblast proliferation and fibrotic gene expression.
• CFAR functions as a competing endogenous RNA (ceRNA) for miR-449a-5p, leading to the derepression of its target gene, LOXL3.
• LOXL3 mimics TGF-β1 activity by activating mTOR, thereby promoting cardiac fibrosis.
• Downregulation of miR-449a-5p exacerbates fibrosis, while its overexpression ameliorates it.

Conclusions:

• CFAR is a novel profibrotic long non-coding RNA that drives cardiac fibrosis.
• The identified miR-449a-5p/LOXL3/mTOR axis represents a new molecular pathway in cardiac fibrosis.
• CFAR emerges as a potential therapeutic target for treating cardiac fibrosis and related heart diseases.