title: A hypothesis for a possible synergy between ghrelin and exercise in patients with cachexia: Biochemical and physiological bases.
abstract: This article reviews the biochemical and physiological observations underpinning the synergism between ghrelin and ghrelin agonists with exercise, especially progressive resistance training that has been shown to increase muscle mass. The synergy of ghrelin agonists and physical exercise could be beneficial in conditions where muscle wasting is present, such as that found in patients with advanced cancer. The principal mechanism that controls muscle anabolism following the activation of the ghrelin receptor in the central nervous system involves the release of growth hormone/insulin-like growth factor-1 (GH/IGF-1). GH/IGF-1 axis has a dual pathway of action on muscle growth: (a) a direct action on muscle, bone and fat tissue and (b) an indirect action via the production of both muscle-restricted mIGF-1 and anti-cachectic cytokines. Progressive resistance training is a potent inducer of the secretion the muscle-restricted IGF-1 (mIGF-1) that enhances protein synthesis, increases lean body mass and eventually leads to the improvement of muscle strength. Thus, the combination of ghrelin administration with progressive resistance training may serve to circumvent ghrelin resistance and further reduce muscle wasting, which are commonly associated with cachexia.
authors.affiliation: McGill Nutrition and Performance Laboratory, McGill University, Montreal, Canada. Electronic address: domencofuoco@live.ca.
authors.forename: Domenico
authors.initials: D
authors.lastname: Fuoco
authors.affiliation: McGill Nutrition and Performance Laboratory, McGill University, Montreal, Canada.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Kilgour
authors.affiliation: McGill Nutrition and Performance Laboratory, McGill University, Montreal, Canada.
authors.forename: Antonio
authors.initials: A
authors.lastname: Vigano
mesh_terms: D000818:Animals; D002100:Cachexia / Q000378:metabolism*; D045744:Cell Line, Tumor; D004435:Eating; D015444:Exercise; D005081:Exercise Therapy; D005260:Female; D054439:Ghrelin / Q000378:metabolism*; D013006:Growth Hormone / Q000378:metabolism; D019382:Human Growth Hormone / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D008962:Models, Theoretical; D009133:Muscular Atrophy / Q000378:metabolism*; D009369:Neoplasms / Q000150:complications / Q000473:pathology; D010805:Physical Conditioning, Animal; D055070:Resistance Training
chemical_list: D054439:Ghrelin; C583557:IGF1 protein, human; C519530:insulin-like growth factor-1, mouse; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone