Histological changes in sarcopenia and the possible protective role of angiotensin-converting enzyme inhibitors in male albino rats

Introduction:Sarcopenia is used to describe the loss of skeletal muscle mass with age. Angiotensin-converting enzyme inhibitors (ACEIs) are used for treatment of hypertension and may have a protective role in age-related changes in skeletal muscle. The aim of the study:The aim of the study was to demonstrate the histological changes of sarcopenia and the possible protective role of ACEIs. Materials and methods:Rats were divided into three groups: group I consisted of adult rats (3–6 months of age); group II consisted of old senile rats (18–24 months of age); and group III consisted of old senile rats that received ACEI (Enalopril Maleate) at a dose of 10 mg/kg once daily by means of an intragastric tube for 12 weeks. At the end of the experiment, the gastrocnemius muscles were dissected and prepared for light and electron microscopical (EM) examination. Morphometric assessment was carried out. Results:In group II, the muscle fibers appeared disrupted, short, and separated by abundant connective tissue. Vacuoles, mononuclear cellular infiltration, and large areas containing acidophilic exudates were found among the connective tissue and muscle fibers. EM examination revealed many electron-lucent vacuoles and electron-dense mitochondria with loss of normal appearance of the sarcomeres. In group III, a few vacuoles and mononuclear cells were noticed. On EM, the sarcomeres showed a regular appearance. There was significant decrease in cross-sectional area, perimeter, and total surface area of muscle fibers in both groups II and III compared with group I and a highly significant increase in the number of nuclei per high-power field only in group II. Conclusion:ACEIs could improve the structure of skeletal muscle in aged sarcopenic rats to some extent.