What is SarcotropinSarcotropin is a medical food containing ingredients that oppose sarcopenia, the progressive loss of muscle or lean body mass (LBM) that occurs during aging. There is scientific evidence that sarcopenia can be at least partially reversed with resistance exercise. Nonetheless, while it is most common in physically inactive individuals, sarcopenia also occurs in people who remain physically active throughout their lives. This suggests that physical inactivity is not the only contributing factor to sarcopenia and that improper nutrition, a decline in hormones, insufficient micronutrients and other negative factors are also contributing causes. In such instances sarcopenia may also be effectively managed with protein-energetic substances that are anabolic to the muscles of aging adults.
To determine which substances are best suited for opposing sarcopenia, it is first necessary to know that the regulation of body composition is dynamic over time. Minute-to-minute composition is regulated by an individual's metabolic state, whereas day-to-day regulation depends upon the interactions of insulin and glucagon. However, long term or month-to-month regulation of body composition is affected by the endocrine and nervous systems. Thus, several contributing factors for development of sarcopenia during aging have been identified. These include progressive age-related attrition of alpha-motor neuron activity, growth hormone production, sex steroid levels, and specific amino acids and vitamins resulting from inadequate intake of dietary energy and protein. In addition, fat gain and increased production of catabolic cytokines, are potentially important factors contributing to development of sarcopenia. Using this scientifically-based information, Sarcotropin has been specifically formulated to oppose the causal molecular deficiencies by combining essential ingredients in a medical food product intended to complement the normal diet.
Recognizing the anabolic value of growth hormone, significant attention has been directed to selection of ingredients for the Sarcotropin formula that increase availability of that specific hormone. In this regard, secretagogues that directly stimulate cells in the pituitary gland called somatotrophs to produce and secrete growth hormone (GH) are particularly effective. One such is a naturally occurring peptide called ghrelin that is produced in certain fruits such as plum and mulberry. The molecule has been shown to have strong GH releasing activity that results from its ability to activate a specific receptor located on the somatotroph called GH secretagogue (GHS) receptor type 1a (GHS-R 1a) (1, see 2). GHS-Rs had been shown to specifically bind a family of synthetic peptide analogs of ghrelin prior to its discovery (3- 6). GHRP-2 is such an analog having the sequence D-Ala-D-beta-Nal-Ala-Trp-D-Phe-Lys-NH2 with a molecular weight of 817.97 daltons. It was originally derived structurally from metenkephalin (see 7). Small quantities of GHRP-2 are included in Sarcotropin to better ensure that the desired clinical effects of ghrelin are realized because of some possible degradation during processing of the fruit juices in which it naturally occurs.
GHS-Rs are concentrated in the hypothalamus-pituitary unit and also widely distributed in central and peripheral tissues thus accounting for the diverse actions of ghrelin upon the body (8-11). These include hypothalamic functions resulting in restored neuroendocrine activity, direct effects on the pituitary gonadal axis at central and peripheral levels, stimulation of appetite and positive energy balance, influence on sleep and behavior, control of gastric motility and acid secretion, and modulation of pancreatic endocrine and exocrine function s affecting glucose homeostasis. Positive cardiovascular actions and modulation of immune function are also reported actions of ghrelin and its analogs such as GHRP-2 (12-16). This wide spectrum of biological activity makes ghrelin a potential candidate having clinical impact and therapeutic potential on various fields of internal medicine such as endocrinology, gastroenterology, immunology and cardiology.
In humans and other mammals, ghrelin is predominantly produced by the stomach. However, it is also detected in the bowel, pancreas, kidneys, immune system, placenta, testes, pituitary, lung and hypothalamus (see 1). It is also found in fish, amphibians, birds, reptiles and surprisingly in some plants. Some of these include Prunus x domestica L., Marus alba and Syzygium aromaticum (17, 18). RIA analysis confirmed that these plants contain significant amounts of this substance and that reverse-phase HPLC analyses of their extracts showed an elution characteristic of the peptide identical to that of human ghrelin. Because of this fact, the fruit juices are dominant constituents of the Sarcotropin formulation serving as natural sources of its active ingredient.
In addition to the naturally occurring active ingredient ghrelin and its analog GHRP-2, additional active ingredients in the Sarcotropin formula include leucine, ?-hydroxy ?-methyl-butyrate (HMB), Vitamin D, glutamine, and an extract of Mucuna pruriens.
Leucine is an insulin secretagogue and also the only dietary amino acid having the capacity to stimulate muscle protein synthesis (19). In older humans, the addition of leucine to a mixed nutrient meal resulted in a significant increase in muscle protein synthesis (0.053 ± 0.009%/h vs. 0.083 ±0.008 %/h, P < 0.05) (20). Conversely, leucine deficits can contribute to reduced muscle protein anabolism and a loss of muscle mass, as seen in acute studies of animals (21) and humans (20). Furthermore, a chemical byproduct of leucine metabolism known as ?-hydroxy-?-methyl butyrate (HMB) inhibits proteolysis or the enzymatic breakdown of protein to thereby oppose loss of muscle mass. These findings are promising for the potential use of leucine and HMB in Sarcotropin to enhance muscle protein synthesis and prevent its breakdown in the elderly.
Vitamin D plays an essential role in muscle growth and development (22) and in regulating muscle contractility. On the other hand, Vitamin D deficiency is associated with a loss of muscle strength (23) and function (22) and an increase in the risk of falling (24). However, there is evidence that these deficits can be improved by vitamin D supplementation supporting a putative role for vitamin D in preventing sarcopenia (25).
L-Glutamine is the most abundant amino acid in muscle cells that provides significant protection against the catabolic effects of stress hormones such as cortisol. It also acts in the nervous system to stimulate the release of growth hormone (26) and thus complements the effects of the primary GHS.
Mucuna pruriens, also called velvet bean or cowitch, is a legume the extracts of which are used for a variety of purposes including treatment of diseases, development of muscle mass and enhancement of growth hormone and testosterone secretion. Its endocrine effects result from the action of L-DOPA, an amino acid that increases brain dopamine which in turn enhances pituitary growth hormone production and release.
Based upon these complementary anabolic effects on muscle, the ingredients found in Sarcotropin are effective and safe for opposing sarcopenia, perhaps the most significant threat to health and vitality that occurs during aging.