Kristina Bečanović, Muhammad Asghar, Izabella Gadawska, Shiny Sachdeva, David Walker, Eduardo R Lazarowski, Sonia Franciosi, Kevin H J Park, Hélène C F Côté, Blair R Leavitt
{"title":"Age-related mitochondrial alterations in brain and skeletal muscle of the YAC128 model of Huntington disease.","authors":"Kristina Bečanović, Muhammad Asghar, Izabella Gadawska, Shiny Sachdeva, David Walker, Eduardo R Lazarowski, Sonia Franciosi, Kevin H J Park, Hélène C F Côté, Blair R Leavitt","doi":"10.1038/s41514-021-00079-2","DOIUrl":null,"url":null,"abstract":"<p><p>Mitochondrial dysfunction and bioenergetics failure are common pathological hallmarks in Huntington's disease (HD) and aging. In the present study, we used the YAC128 murine model of HD to examine the effects of mutant huntingtin on mitochondrial parameters related to aging in brain and skeletal muscle. We have conducted a cross-sectional natural history study of mitochondrial DNA changes in the YAC128 mouse. Here, we first show that the mitochondrial volume fraction appears to increase in the axons and dendrite regions adjacent to the striatal neuron cell bodies in old mice. Mitochondrial DNA copy number (mtDNAcn) was used as a proxy measure for mitochondrial biogenesis and function. We observed that the mtDNAcn changes significantly with age and genotype in a tissue-specific manner. We found a positive correlation between aging and the mtDNAcn in striatum and skeletal muscle but not in cortex. Notably, the YAC128 mice had lower mtDNAcn in cortex and skeletal muscle. We further show that mtDNA deletions are present in striatal and skeletal muscle tissue in both young and aged YAC128 and WT mice. Tracking gene expression levels cross-sectionally in mice allowed us to identify contributions of age and genotype to transcriptional variance in mitochondria-related genes. These findings provide insights into the role of mitochondrial dynamics in HD pathogenesis in both brain and skeletal muscle, and suggest that mtDNAcn in skeletal muscle tissue may be a potential biomarker that should be investigated further in human HD.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.4000,"publicationDate":"2021-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8516942/pdf/","citationCount":"8","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"NPJ Aging and Mechanisms of Disease","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1038/s41514-021-00079-2","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GERIATRICS & GERONTOLOGY","Score":null,"Total":0}
引用次数: 8
Abstract
Mitochondrial dysfunction and bioenergetics failure are common pathological hallmarks in Huntington's disease (HD) and aging. In the present study, we used the YAC128 murine model of HD to examine the effects of mutant huntingtin on mitochondrial parameters related to aging in brain and skeletal muscle. We have conducted a cross-sectional natural history study of mitochondrial DNA changes in the YAC128 mouse. Here, we first show that the mitochondrial volume fraction appears to increase in the axons and dendrite regions adjacent to the striatal neuron cell bodies in old mice. Mitochondrial DNA copy number (mtDNAcn) was used as a proxy measure for mitochondrial biogenesis and function. We observed that the mtDNAcn changes significantly with age and genotype in a tissue-specific manner. We found a positive correlation between aging and the mtDNAcn in striatum and skeletal muscle but not in cortex. Notably, the YAC128 mice had lower mtDNAcn in cortex and skeletal muscle. We further show that mtDNA deletions are present in striatal and skeletal muscle tissue in both young and aged YAC128 and WT mice. Tracking gene expression levels cross-sectionally in mice allowed us to identify contributions of age and genotype to transcriptional variance in mitochondria-related genes. These findings provide insights into the role of mitochondrial dynamics in HD pathogenesis in both brain and skeletal muscle, and suggest that mtDNAcn in skeletal muscle tissue may be a potential biomarker that should be investigated further in human HD.
期刊介绍:
npj Aging and Mechanisms of Disease is an online open access journal that provides a forum for the world’s most important research in the fields of aging and aging-related disease. The journal publishes papers from all relevant disciplines, encouraging those that shed light on the mechanisms behind aging and the associated diseases. The journal’s scope includes, but is not restricted to, the following areas (not listed in order of preference): • cellular and molecular mechanisms of aging and aging-related diseases • interventions to affect the process of aging and longevity • homeostatic regulation and aging • age-associated complications • translational research into prevention and treatment of aging-related diseases • mechanistic bases for epidemiological aspects of aging-related disease.