Sarcopenia and Androgens: A Link between Pathology and Treatment

Abstract

Sarcopenia, the age-related loss of skeletal muscle mass and function, is becoming more prevalent as the lifespan continues to increase in most populations. As sarcopenia is highly disabling, being associated with increased risk of dependence, falls, fractures, weakness, disability, and death, development of approaches to its prevention and treatment are required. Androgens are the main physiologic anabolic steroid hormones and normal testosterone levels are necessary for a range of developmental and biological processes, including maintenance of muscle mass. Testosterone concentrations decline as age increase, suggesting that low plasma testosterone levels can cause or accelerate muscle-and age-related diseases, as sarcopenia. Currently, there is increasing interest on the anabolic properties of testosterone for therapeutic use in muscle diseases including sarcopenia. However, the pathophysiological mechanisms underlying this muscle syndrome and its relationship with plasma level of androgens are not completely understood. This review discusses the recent findings regarding sarcopenia, the intrinsic, and extrinsic mechanisms involved in the onset and progression of this disease and the treatment approaches that have been developed based on testosterone deficiency and their implications.

Clinical utility of the Liver Frailty Index for predicting muscle atrophy in chronic liver disease patients with hepatocellular carcinoma

“…31 Women have low plasma testosterone levels, which cause muscle atrophy. 32 Thus, physical activity and sex hormones could be possible reasons for the sex difference of muscle mass in the present study.…”

Beyond the X Factor: Relevance of Sex Hormones in NAFLD Pathophysiology

“…Testosterone prevents protein catabolism by inhibiting the hepatic urea cycle [ 196 ], thus reducing hepatic loss of nitrogen and sparing AA for protein synthesis. Such a mechanism could explain, at least in part, the strong correlation between the reduced levels of testosterone and the increased incidence of sarcopenia in aging men [ 198 ] and could partly account for sex differences in muscle wasting [ 199 ].…”

“…The association between low androgen levels, reduced physical activity and NAFLD development in the two sexes has been little investigated. However, the strong correlation between sarcopenia and the increased incidence of NAFLD in aging men [ 198 , 454 , 455 ], as well as between high androgen levels and sarcopenia in PCOS women [ 456 ], suggest that low physical activity may further negatively impact on the development and progression of NAFLD in both men and women with altered androgen levels. However, in these physiopathological conditions, reduced physical activity can be a confounding factor, since both, aging men and PCOS women, that are often overweight or obese, move to a less extent than young men or lean women.…”

The Aging of Skeletal Muscle and Potential Therapeutic Effects of Extracts from Edible and Inedible Plants

“…Epidemiological studies show a significant relationship between low testosterone level and loss of muscle mass, strength, and function, in an elderly population (Rolland et al, 2008). According to Basualto-Alarcón et al (2014), testosterone stimulated protein synthesis via short-and long-term mechanisms. Therefore, there is a possibility that testosterone impairment may also affect protein synthesis, although the exact mechanism remains under investigation.…”