Phytoecdysteroids, which are structurally similar or identical to insect molting hormones, produce a range of effects in mammals, including increasing growth and physical performance. To study the mechanism of action of phytoecdysteroids in mammalian tissue, an in vitro cellular assay of protein synthesis was developed. In C2C12 murine myotubes and human primary myotubes, phytoecdysteroids increased protein synthesis by up to 20%. In vivo, ecdysteroids increased rat grip strength. Ecdysteroid-containing plant extracts produced similar results. The effect was inhibited by a phosphoinositide kinase-3 inhibitor, which suggests a PI3K-mediated mechanism.

In healthy older adults at risk for functional decline, administration of the oral GHS capromorelin may improve body composition and physical function.

No abstract

. Can. J. Chem. 69, 1273Chem. 69, (1991.AK1401 is a mutant of Pseudomonas aeruginosa strain PA01 (serotype 05) that does not express 0-antigen, but does express "A-band" lipopolysaccharide (LPS). The polysaccharide portion of the A-band LPS (A-PS) from AK1401 was found to consist mainly of D-rhamnose, with smaller amounts of 3-0-methylrhamnose, ribose, mannose, glucose, and a 3-0-methylhexose. 'H nuclear magnetic resonance spectra of the intact A-PS indicated that the main structural feature was a repeating trisaccharide of a-D-rhamnose having the following structure:The 'H NMR spectrum of the repeating unit was completely assigned through the use of 2D shift-correlated and relayed coherence transfer NMR spectroscopy. ' The linkage positions and sequence of residues were found by nuclear Overhauser enhancement difference spectroscopy. Le AK1401 est une espkce mutante du Pselcdomonas aeruginosa de la lignte PA01 (strotype 0 5 ) qui n'exprime pas de 0-antigkne, mais qui exprime un lipopolysaccharide (LPS) de abande-A),. On a trouvC que la portion polysaccharide du LPS de bande-A du AK1401 est principalement formCe de D-rhamnose, avec des quantitCs plus faibles de 3-0-mtthylrhamnose, de ribose, de mannose, de glucose et d'un 3-0-mtthylhexose. Les spectres de rtsonance magnCtique nucltaire du 'H du PS-A indiquent que la caracttristique structurale principale est un motif trisaccharide de a-D-rhamnose, de structure : Faisant appel2 la RMN en 2D avec corrtlation des dtplacernents et transfert de cohCrence par relais, on a fait une attribution complkte du spectre RMN du 'H du motif. On a dttermint les positions de liaison et la stquence des rtsidus par l'effet Overhauser nuclCaire differentiel.

Our results are encouraging in that they suggest an effect of growth hormone on a specific aging-correlated deficit. IGF-I was increased by administrating rhGH and muscle strength was increased by exercise. The administration of rhGH to frail older individuals in this study resulted in significant changes in the proportions of fiber types. Whether changes in fiber cross-sectional area or absolute number occur with long-term growth hormone administration requires further study.