Open AccessGene therapy restores mitochondrial function and protects retinal ganglion cells in optic neuropathy induced by a mito-targeted mutant ND1 gene
Author(s) -
Yuan Liu,
Jeremy D Eastwood,
Diego Alba,
Sindhu Velmurugan,
Ning Sun,
Vittorio Porciatti,
Richard K. Lee,
William W. Hauswirth,
John Guy,
Hong Yu
Publication year - 2022
Publication title -
gene therapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.332
H-Index - 159
eISSN - 1476-5462
pISSN - 0969-7128
DOI - 10.1038/s41434-022-00333-6
Subject(s) - biology , genetic enhancement , mitochondrial dna , retinal degeneration , optic nerve , optic neuropathy , mitochondrion , mutant , gene delivery , mitochondrial disease , mitochondrial fusion , mitochondrial respiratory chain , microbiology and biotechnology , gene , genetics , neuroscience
Therapies for genetic disorders caused by mutated mitochondrial DNA are an unmet need, in large part due barriers in delivering DNA to the organelle and the absence of relevant animal models. We injected into mouse eyes a mitochondrially targeted Adeno-Associated-Virus (MTS-AAV) to deliver the mutant human NADH ubiquinone oxidoreductase subunit I (hND1/m.3460 G > A) responsible for Leber's hereditary optic neuropathy, the most common primary mitochondrial genetic disease. We show that the expression of the mutant hND1 delivered to retinal ganglion cells (RGC) layer colocalizes with the mitochondrial marker PORIN and the assembly of the expressed hND1 protein into host respiration complex I. The hND1-injected eyes exhibit hallmarks of the human disease with progressive loss of RGC function and number, as well as optic nerve degeneration. We also show that gene therapy in the hND1 eyes by means of an injection of a second MTS-AAV vector carrying wild-type human ND1 restores mitochondrial respiratory complex I activity, the rate of ATP synthesis and protects RGCs and their axons from dysfunction and degeneration. These results prove that MTS-AAV is a highly efficient gene delivery approach with the ability to create mito-animal models and has the therapeutic potential to treat mitochondrial genetic diseases.