Year: 2010
Type: dissertation
Abstract: Although androgens are known to exert anabolic effects in skeletal muscle,\noverexpression of androgen receptor (AR) selectively in this tissue causes androgen dependent motor deficits and muscular atrophy. The cellular and subcellular changes\nunderlying this phenotype are unknown. Therefore, this study aimed to elucidate the\nultrastructural and histologic changes accompanying myopathy and to determine the\nimportance of androgens and overexpression level for myopathic features. Transmission\nelectron microscopy revealed augmented mitochondrial content and reduced myofibril\nwidth in androgen exposed transgenics. Additionally, male transgenics demonstrated\nincreased glycogen content. Histochemical analyses confirmed sex-specific changes in\nglycogen content and revealed a surprising loss in the proportion of oxidative fibers in\nsymptomatic animals. However, increased mitochondrial content was confirmed by the\npresence of ragged red fibers. Overexpression of AR in muscle fiber results in mitochondrial pathology and dysregulation of glycogen metabolism, possibly reflecting\nnormal but exaggerated function of androgens in skeletal muscle fibers.
Source: TSpace (University of Toronto)
Author: Mutaz Musa
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2638371964