Insulin-like substances

Fig. (1). Insulin-like Substance in Korean Red Ginseng As shown in "Fig. (2) and Fig. (3)", adenosine and pyroglutamic acid inhibited norepinephrine-induced lipolysis dose-dependently.

It is not quite clear how growth hormone exerts its effect at the cellular level. One hypothesis proposes that the major function of the hormone is to stimulate protein synthesis and that this is achieved by the release of insulin-like substances namely, somatomedin A and B. These substances are found in plasma, but their chemical structure is still unknown. Two somato-medins have been found in plasma a large (mol wt 44,000) and a small one (mol wt 22,000). Although there is no evidence of conversion of the large into the small somatomedin, it has been proposed that the high is a precursor of the low molecular weight component [166]. 

Plasma Factors that Influence Insulin Action. Berson and Yalow argue persuasively that there is no evidence that insulin of pancreatic origin ever becomes bound to a plasma protein, from which it can subsequently be released in recognizable form. 2 Newer evidence, based on an examination of the insulin-like activity of plasma, from which all immunoreactive insulin had been precipitated with anti-insulin serum, confirms this conclusion. 3 Nevertheless, there is ample evidence that there exist in plasma, substances that have insulin-like activity or that can modify the... 

Synthesis of Glycosylated Natural Products.—The 2-araino-2-deoxy-a-D-glucosyl-m3 o-inositol phosphate (38), which was predicted to have insulin-like activity, has been synthesised, as have 3-0-(2-amino-2-deoxy-a-D-galactopyranosyl)-D-c/iiro-inositol and 6-C)-(a-D-mannopyranosyl)-D-myo-inositol which is a fragment of mycobacteria phospholipids. Compound (39), which is a key substance for the synthesis of distomycin... 

Two papers have dealt with the conformational analysis of mannobioses, the latter considering methyl 3-O-mannopyranosyl-a-D-mannopyranoside specifically. A report has appeared on the preparation of methyl 2-0-(6-deoxy-6-fluoro-a-D-mannopyranosyl)-a-D-mannopyranoside and of the isomer with the fluorine atom in the "reducing" moiety, and of several related substances. 2-0- -D-Mannopyranosyl-D-mannopyranose has been incorporated into a pentafluorophenylthreonate compound and hence into a glycosylated peptide unit of insulin-like growth factor. ... 

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