HDAC4-myogenin axis as an important marker of HD-related skeletal muscle atrophy.
Skeletal muscle remodelling and contractile dysfunction occur through both acute and chronic disease processes. These include the accumulation of insoluble aggregates of misfolded amyloid proteins that is a pathological feature of Huntington's disease (HD). While HD has been described primarily as a neurological disease, HD patients' exhibit pronounced skeletal muscle atrophy. Given that huntingtin is a ubiquitously expressed protein, skeletal muscle fibres may be at risk of a cell autonomous HD-related dysfunction. However the mechanism leading to skeletal muscle abnormalities in the clinical and pre-clinical HD settings remains unknown. To unravel this mechanism, we employed the R6/2 transgenic and HdhQ150 knock-in mouse models of HD. We found that symptomatic animals developed a progressive impairment of the contractile characteristics of the hind limb muscles tibialis anterior (TA) and extensor digitorum longus (EDL), accompanied by a significant loss of motor units in the EDL. In symptomatic animals, these pronounced functional changes were accompanied by an aberrant deregulation of contractile protein transcripts and their up-stream transcriptional regulators. In addition, HD mouse models develop a significant reduction in muscle force, possibly as a result of a deterioration in energy metabolism and decreased oxidation that is accompanied by the re-expression of the HDAC4-DACH2-myogenin axis. These results show that muscle dysfunction is a key pathological feature of HD.
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Michal
M
Mielcarek
Department of Biochemistry, Medical University of Gdansk, Gdansk, Poland.
Marta
M
Toczek
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Cleo J L M
CJ
Smeets
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Sophie A
SA
Franklin
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Marie K
MK
Bondulich
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Nelly
N
Jolinon
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Thomas
T
Muller
Sobell Department of Motor Neuroscience and Movement Disorders and MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, United Kingdom.
Mhoriam
M
Ahmed
Sobell Department of Motor Neuroscience and Movement Disorders and MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, United Kingdom.
James R T
JR
Dick
MRC National Institute for Medical Research, London, United Kingdom.
Izabela
I
Piotrowska
Sobell Department of Motor Neuroscience and Movement Disorders and MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, United Kingdom.
Linda
L
Greensmith
Department of Biochemistry, Medical University of Gdansk, Gdansk, Poland; Department of Surgery and Translational Medicine, University of Milano-Bicocca, Milano, Italy.
Ryszard T
RT
Smolenski
Department of Medical and Molecular Genetics, King's College London, London, United Kingdom.
Gillian P
GP
Bates
D000818:Animals; D001284:Atrophy; D055879:Gene Knock-In Techniques; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D006816:Huntington Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008822:Mice, Transgenic; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology*; D018008:Myogenin / Q000378:metabolism; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism
D018008:Myogenin; D050486:Serotonin Plasma Membrane Transport Proteins; C493231:Slc6a4 protein, mouse; C498618:Hdac5 protein, mouse; D006655:Histone Deacetylases