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Van Wittenberghe, L.

Publications and source records attributed to Van Wittenberghe, L..

2 recordsLinked to original sources

Targeting lysosomal damage is a new therapeutic perspective for Duchenne Muscular Dystrophy

Duchenne Muscular Dystrophy (DMD), a muscle degenerative disease affecting young boys, arises from the loss of dystrophin. Current gene therapy approaches aim to restore a shortened form of dystrophin (microdystrophin) via Adeno-Associated Vector (AAV) delivery, but clinical studies show limited efficacy, emphasizing the need for improved strategies such as combined therapies. In this study, we identified lysosomal perturbations in the myofibers of DMD patients and animal models, an overlooked mechanism of cellular damage in muscular dystrophies. These were notably marked by the upregulation and recruitment of Galectin-3, a known biomarker of lysosomal membrane permeabilization, to damaged lysosomes, alongside alterations in lysosome number, morphology, and activation of endolysosomal damage response. Importantly, microdystrophin therapy in Dmdmdx mice fails to fully correct these damages. However, combining it with trehalose, a lysosome-protective disaccharide, significantly improves outcome, enhancing muscle function, histology and transcriptome. These findings highlight lysosomal damage as a novel mechanism in DMD pathogenesis and suggest that combining trehalose with gene therapy could enhance therapeutic efficacy. TeaserLysosomal damage contributes to DMD pathology and is an interesting therapeutic target worth considering for current and future approaches.

physiology↗

Rescue of lysosomal acid lipase deficiency in mice by rAAV8 liver gene transfer.

Lysosomal acid lipase deficiency (LAL-D) is an autosomal recessive disorder caused by mutations in the LIPA gene, which results in lipid accumulation leading to multi-organ failure. If left untreated, the severe form of LAL-D results in premature death within the first year of life due to failure to thrive and hepatic insufficiency. Enzyme replacement therapy is the only available supportive treatment consisting in weekly systemic injections of recombinant LAL protein. Here, we characterized a novel Lipa-/- mouse model and developed a curative gene therapy treatment based on the in vivo administration of recombinant (r)AAV8 vector encoding the human LIPA transgene under the control of a hepatocyte-specific promoter. We defined the minimal rAAV8 dose required to rescue disease lethality and to correct cholesterol and triglyceride accumulation in multiple organs and blood. Finally, using liver transcriptomic and biochemical analysis, we showed mitochondrial impairment in Lipa-/- mice and its recovery by gene therapy. Overall, our in vivo gene therapy strategy achieves a stable long-term LAL expression sufficient to correct the disease phenotype in the Lipa-/-mouse model and offers a new therapeutic option for LAL-D patients. One Sentence SummaryWeve developed a liver-targeted gene therapy using recombinant AAV8 to effectively cure Lysosomal acid lipase deficiency by correcting lipid accumulation and by normalizing gene expression pattern and mitochondrial function in Lipa-/- mouse model.

molecular biology↗