Abstract
Carbohydrate-based infusion solutions are widely used in the clinic. Here we show that co-administration of phosphorodiamidate morpholino oligomers (PMOs) with glucose enhances exon-skipping activity in Duchenne muscular dystrophy (DMD) mdx mice. We identify a glucose–fructose (GF) formulation that potentiates PMO activity, completely corrects aberrant Dmd transcripts, restores dystrophin levels in skeletal muscles and achieves functional rescue without detectable toxicity. This activity is attributed to enhancement of GF-mediated PMO uptake in the muscle. We demonstrate that PMO cellular uptake is energy dependent, and that ATP from GF metabolism contributes to enhanced cellular uptake of PMO in the muscle. Collectively, we show that GF potentiates PMO activity by replenishing cellular energy stores under energy-deficient conditions in mdx mice. Our findings provide mechanistic insight into hexose-mediated oligonucleotide delivery and have important implications for the development of DMD exon-skipping therapy.
Highlights
Carbohydrate-based infusion solutions are widely used in the clinic
Up to 2% of wild-type dystrophin level was observed in quadriceps from mdx mice treated with phosphorodiamidate morpholino oligomers (PMOs)-GF, compared with o1% dystrophin following PMO in saline (PMO-S) treatment (Fig. 1d)
Up to 20% of wild-type dystrophin protein level was restored in abdominal muscles from mdx mice treated with PMO in GF (PMO-GF) at 50 mg kg À 1 (Supplementary Fig. 1b, n 1⁄4 6), whereas B15 or 2.5% was restored following PMO-S treatment at 100 or 50 mg kg À 1, respectively (Supplementary Fig. 1b, n 1⁄4 6)
Summary
Separating GF from PMO negated the enhancement observed with PMO-GF (Fig. 3a,b), suggesting that GF probably potentiates PMO activity by enhancing uptake rather than exon-skipping frequency This notion is supported by significantly increased PMO uptake in all peripheral muscles following intravenous administration of lissamine-labelled PMO-GF compared with PMO-S (Fig. 3c, n 1⁄4 6). This resulted in a significant decrease of dystrophin expression in shPFK-treated muscles compared with SC, following the introduction of PMO-GF (Fig. 4e,f, n 1⁄4 6), indicating that metabolism of GF is critical for the observed potentiating effect. These findings provide direct evidence that ATP generated by GF facilitates PMO uptake under energy-deficient cellular conditions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
