title: Molecular mechanisms of treadmill therapy on neuromuscular atrophy induced via botulinum toxin A.
abstract: Botulinum toxin A (BoNT-A) is a bacterial zinc-dependent endopeptidase that acts specifically on neuromuscular junctions. BoNT-A blocks the release of acetylcholine, thereby decreasing the ability of a spastic muscle to generate forceful contraction, which results in a temporal local weakness and the atrophy of targeted muscles. BoNT-A-induced temporal muscle weakness has been used to manage skeletal muscle spasticity, such as poststroke spasticity, cerebral palsy, and cervical dystonia. However, the combined effect of treadmill exercise and BoNT-A treatment is not well understood. We previously demonstrated that for rats, following BoNT-A injection in the gastrocnemius muscle, treadmill running improved the recovery of the sciatic functional index (SFI), muscle contraction strength, and compound muscle action potential (CMAP) amplitude and area. Treadmill training had no influence on gastrocnemius mass that received BoNT-A injection, but it improved the maximal contraction force of the gastrocnemius, and upregulation of GAP-43, IGF-1, Myo-D, Myf-5, myogenin, and acetylcholine receptor (AChR) subunits α and β was found following treadmill training. Taken together, these results suggest that the upregulation of genes associated with neurite and AChR regeneration following treadmill training may contribute to enhanced gastrocnemius strength recovery following BoNT-A injection.
authors: Department of Life Sciences, Agricultural Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan ; Department of Physical Medicine and Rehabilitation, School of Medicine, Tzu Chi University, Hualien 970, Taiwan ; Department of Physical Medicine and Rehabilitation, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung 404, Taiwan ; Center of General Education, National Taichung University of Science and Technology, Taichung 404, Taiwan.
authors: Sen-Wei
authors: SW
authors: Tsai
authors: Hsiao-Ling
authors: HL
authors: Chen
authors: Yi-Chun
authors: YC
authors: Chang
authors: Chuan-Mu
authors: CM
authors: Chen
mesh_terms: D000818:Animals; D001284:Atrophy; D019274:Botulinum Toxins, Type A / Q000737:chemistry / Q000494:pharmacology / Q000633:toxicity*; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D009128:Muscle Spasticity / Q000503:physiopathology / Q000628:therapy; D009132:Muscles / Q000473:pathology; D009468:Neuromuscular Diseases / Q000139:chemically induced* / Q000628:therapy*; D009469:Neuromuscular Junction / Q000187:drug effects / Q000648:ultrastructure; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats
chemical_list: D019274:Botulinum Toxins, Type A