️ Episode 173: Bottlebrush Block Copolymer Shields Muscles and Prevents DMD Onset

In this episode of PaperCast Base by Base, we explore a PNAS study showing how a synthetic bottlebrush block copolymer can act as a powerful membrane stabilizer to protect dystrophin-deficient muscle in Duchenne muscular dystrophy.

Study Highlights:
Researchers engineered and tested an amphiphilic bottlebrush diblock polymer, B–PEO43_10–PPO15_5, as a membrane stabilizer in the mdx mouse model of Duchenne muscular dystrophy. At nanomolar doses, the polymer rapidly restored twitch contractility in single dystrophin‑deficient fibers and showed ~150,000‑fold greater potency than optimized linear PEO–PPO copolymers. Early systemic dosing from postnatal day 1 to 21 prevented the surge of serum creatine kinase and blocked histologic hallmarks of damage in tibialis anterior and diaphragm while routine liver and kidney panels remained normal. In adult mice, pretreatment prevented IgG entry into myocardium during isoproterenol stress and significantly improved survival during combined handling and β‑adrenergic stress tests.

Conclusion:
This work positions bottlebrush block copolymers as fast‑acting, mutation‑agnostic membrane stabilizers with potential to preserve skeletal, respiratory, and cardiac muscle when deployed early and to complement gene‑based therapies.

Reference:
Cohen H, Bez Batti Angulski A, Quick JD, Kuebler TS, Thompson BR, Bauer J, Hahn D, Townsend D, Hassler JF, Hackel BJ, Lodge TP, Sham YY, Bates FS, Metzger JM. Synthetic bottlebrush block copolymer prevents disease onset in Duchenne muscular dystrophy. Proceedings of the National Academy of Sciences. 2025;122(42):e2513599122. https://doi.org/10.1073/pnas.2513599122

License:
This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/

Support:
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Chapters

• (00:00:00 ) - Duchenne Muscular Dystrophy: Chemical repair
• (00:02:37 ) - Synthetic Polymers to stabilize muscle membranes in DC motor dys
• (00:07:40 ) - Heart failure in MDX mice
• (00:08:48 ) - Bottle Brush Polymer
• (00:12:58 ) - Bottle Brush polymer
• (00:18:14 ) - Deep Dive: Synthetic polymer fixes dystrophic muscle disease
• (00:19:31 ) - Thinking beyond biological replacement to physical synthetic replacement