Gene Therapy Breakthrough: Researchers Develop Exercise Mimetics to Reduce Cardiotoxicity

Researchers at Shanghai University have discovered a novel approach to mitigating the cardiotoxic effects of doxorubicin, a chemotherapy drug commonly used to treat various types of cancer. By developing an RNA-targeting technology using the CRISPR-hfCas13x system, the team has successfully created exercise mimetics that can alleviate doxorubicin-induced cardiotoxicity. This breakthrough has significant implications for improving cancer treatment outcomes and reducing the risk of heart-related complications.

Key Takeaways:

• Researchers at Shanghai University have developed an exercise mimetic technology using the CRISPR-hfCas13x system to reduce cardiotoxicity caused by doxorubicin.
• The technology targets the expression of METTL14, a protein that is increased in doxorubicin-treated hearts but decreased in exercised hearts.
• The exercise mimetics effectively inhibited the expression of METTL14 in the heart, alleviating doxorubicin treatment-induced cardiac dysfunction and cardiac fibrosis.
• The study used adult male mice to induce exercise-induced physiological cardiac hypertrophy and demonstrated that METTL14 overexpression inhibited exercise-induced hypertrophy.
• The research team used an adeno-associated virus 9-mediated METTL14 overexpression system and an RNA N6-methyladenosine inhibitor, STM2457, to modulate global total RNA m6A levels in vivo.
• The CRISPR-cr3-4/hfCas13x system was generated by hfCas13x guided crRNA3 and crRNA4 targeting the Mettl14 expressed under the ctnt promoter and packaged in an adeno-associated virus 9.
• This technology has the potential to generate exercise mimetics that can mimic the beneficial effects of exercise training to attenuate doxorubicin-induced cardiotoxicity.
• The study suggests that targeting Mettl14 suppression could be a therapeutic strategy for doxorubicin-induced cardiotoxicity.

Statistics:

• The researchers used adult male mice to induce exercise-induced physiological cardiac hypertrophy.
• The mice were swim-trained twice a day for 4 weeks to induce exercise-induced physiological cardiac hypertrophy.
• METTL14 was increased in doxorubicin-treated hearts by approximately 20% compared to exercised hearts.
• The exercise mimetics effectively inhibited the expression of METTL14 in the heart by approximately 30% compared to controls.
• The study demonstrated that CRM-ac3-4/hfCas13x effectively alleviated doxorubicin-induced cardiotoxicity in adult male mice.

Sources:

• Targeting Mettl14 Using an RNA-Targeting Clustered Regularly Interspaced Short Palindromic Repeat-High-Fidelity Cas13x System Attenuates Doxorubicin-Induced Cardiotoxicity. Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease, 2025,14(15).
• NewsRx. Researchers from Shanghai University Discuss Findings in Gene Therapy (Targeting Mettl14 Using an RNA-Targeting Clustered Regularly Interspaced Short Palindromic Repeat-High-Fidelity Cas13x System Attenuates Doxorubicin-Induced Cardiotoxicity). Cancer Weekly. August 19, 2025; p 82.