Modified Polycyclic Compounds Rescue Mis-splicing in Myotonic Dystrophy Type 1 Disease Models

Area of Science:

• Biochemistry
• Genetics
• Pharmacology

Background:

• Myotonic dystrophy type 1 (DM1) is a severe genetic disorder with no targeted treatments.
• DM1 pathogenesis involves expanded CUG repeat RNA (CUGexp) sequestering MBNL proteins, causing splicing errors.

Purpose of the Study:

• To develop novel therapeutics for DM1.
• To identify compounds that can rescue DM1-associated splicing defects.

Main Methods:

• Screening of modified polycyclic compounds (MPCs) in DM1 patient-derived cell lines.
• Testing lead compounds (MPC03, MPC04) in a DM1 mouse model.
• RNA binding assays and computational modeling to elucidate mechanism of action.

Main Results:

• MPC03 and MPC04 rescued DM1 splicing defects at low nanomolar concentrations with no observed toxicity.
• In vivo treatment reduced CUGexp RNA levels and partially corrected mis-splicing in a DM1 mouse model.
• MPCs bind to CUGexp RNA, displacing MBNL proteins and restoring normal splicing.

Conclusions:

• Modified polycyclic compounds (MPCs) represent a promising new class of therapeutics for DM1.
• MPCs effectively target the disease mechanism by interacting with CUGexp RNA.
• These compounds demonstrate therapeutic potential across cellular and animal models of DM1.