The authors express their appreciation to Dr. Barbara Schneeman, University of California, for her review of this manuscript and the opportunity for discussion of key points of the manuscript. Referee: Dr. Joanne Slavin, Food Science and Nutrition, University of Minnesota, 1334 Eckles Avenues, St. Paul, MN 5108 This critical review article examines the composition and source of inulin and oligofructose, the physiological effects of their consumption, and how these materials relate to the concept of dietary fiber. Inulin and oligofructose are fructans extracted on a commercial basis from the chicory root. Inulin has been defined as a polydisperse carbohydrate material consisting mainly, if not exclusively, of beta (2-1) fructosyl-fructose links ranging from 2 to 60 units long. Native chicory inulin has an average degree of polymerization (DP) of 10 to 20, whereas oligofructose contains chains of DP 2 to 10, with an average DP of 4. While a universally accepted definition for dietary fiber does not exist, it is generally agreed that this term includes saccharides (+lignin) that are not hydrolyzed or absorbed in the upper part of the gastrointestinal tract. These materials reach the colon, where they may be totally fermented, partially fermented, or remain unfermented. In addition, fibers contribute to fecal bulking. Inulin and oligofructose are not digested in the upper part of the gastrointestinal tract or are they absorbed and metabolized in the glycolytic pathway, or directly stored as glycogen like ‘sugars’ or starches. None of the molecules of fructose and glucose that form inulin and oligofructose appear in the portal blood. These materials are quantitatively fermented by the micro flora of the colon; further, it has been demonstrated that this fermentation leads to the selective stimulation of the growth of the bifidobacteria population. After reviewing their chemistry, origin, and physiological effects, it is the opinion of the authors that inulin and oligofructose are dietary fiber. They share the basic common characteristics of dietary fibers, that is, saccharides of plant origin, resistance to digestion and absorption in the small intestine, and fermentation in the colon to produce short-chain fatty acids that are absorbed and metabolized in various parts of the body. Moreover, this fermentation induces a bulking effect.

This critical review article examines the composition and source of inulin and oligofructose, the physiological effects of their consumption, and how these materials relate to the concept of dietary fiber. Inulin and oligofructose are fructans extracted on a commercial basis from the chicory root. Inulin has been defined as a polydisperse carbohydrate material consisting mainly, if not exclusively, of beta (2-1) fructosyl-fructose links ranging from 2 to 60 units long. Native chicory inulin has an average degree of polymerization (DP) of 10 to 20, whereas oligofructose contains chains of DP 2 to 10, with an average DP of 4.While a universally accepted definition for dietary fiber does not exist, it is generally agreed that this term includes saccharides (+ lignin) that are not hydrolyzed or absorbed in the upper part of the gastrointestinal tract. These materials reach the colon, where they may be totally fermented, partially fermented, or remain unfermented. In addition, fibers contribute to fecal bulking.Inulin and oligofructose are not digested in the upper part of the gastrointestinal tract or are they absorbed and metabolized in the glycolytic pathway, or directly stored as glycogen like 'sugars' or starches. None of the molecules of fructose and glucose that form inulin and oligofructose appear in the portal blood. These materials are quantitatively fermented by the microflora of the colon; further, it has been demonstrated that this fermentation leads to the selective stimulation of the growth of the bifidobacteria population.After reviewing their chemistry, origin, and physiological effects, it is the opinion of the authors that inulin and oligofructose are dietary fiber. They share the basic common characteristics of dietary fibers, that is, saccharides of plant origin, resistance to digestion and absorption in the small intestine, and fermentation in the colon to produce short-chain fatty acids that are absorbed and metabolized in various parts of the body. Moreover, this fermentation induces a bulking effect.

Excessive dietary Fe is known to be toxic, but the extent of neurobiological involvement is not clear. In the present study male weanling rats were fed diets containing Fe at 35 (control), 350, 3500, or 20000 ppm for 12 wk. An Fe-deficient group (4 ppm) was included for comparison. Rats were tested for behavioral and body weight changes at various times after initiation of diets, and liver and brain nonheme Fe were measured at term. Excess dietary Fe, primarily at 20000 ppm, significantly decreased activity, habituation, reflex startle, and conditioned avoidance response performance, and enhanced prepulse modulation of startle. Body weights were also markedly decreased. Fe-deficient animals showed similar behavioral effects but more moderate body weight changes. Liver nonheme Fe varied directly with dietary levels. Whole-brain nonheme Fe was significantly reduced in Fe-deficient animals but increased only at the 20000-ppm level. Homeostatic mechanisms appear to regulate whole-brain Fe more effectively under conditions of dietary Fe overload than under conditions of Fe deficiency. The behavioral changes associated with dietary Fe overload may represent secondary consequences of systemic toxicity.

Administration of adrenaline to an isolated rat hindlimb preparation rapidly decreased muscle phosphorylase phosphatase (EC 3.1.3.17) activity and increased heat-stable and trypsin-labile phosphatase inhibitor activity. This was associated with increased tissue cyclic AMP concentrations, phosphorylase (EC 2.4.1.1) activation and glycogen synthase (EC 2.4.1.11) inactivation.

A heat- and acid-stable proten inhibitor of phosphorylase phosphatase is present in a highly purified preparation of protein inhibitor of cyclic AMP-dependent protein kinase from rabbit skeletal muscle. Although these two inhibitors have strikingly similar properties to each other, such as sensitivity to trypsin and behavior on gel permeation chromatography, they can be separated by polyacrylamide disc gel electrophoresis. This indicates that the phosphatase-inhibitory and kinase-inhibitory activities reside with different protein species. The inhibition of both the enzymes is not altered by incubating the inhibitor preparation with a general phosphoprotein phosphatase, with phosvitin kinase, or with cyclic AMP-dependent protein kinase. Inhibition of phosphorylase phosphatase is of a non-competitive type supporting the idea that the phosphatase inhibitor is not an alternative substrate for the enzyme. Inhibition of phosphatase activity is selective in that it does not occur when phosphorylated histone or phosphorylated protamine are used as substrates.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInteractions between polyamines and nucleotidesChiharu Nakai and Walter GlinsmannCite this: Biochemistry 1977, 16, 25, 5636–5641Publication Date (Print):December 13, 1977Publication History Published online1 May 2002Published inissue 13 December 1977https://pubs.acs.org/doi/10.1021/bi00644a039https://doi.org/10.1021/bi00644a039research-articleACS PublicationsRequest reuse permissionsArticle Views169Altmetric-Citations69LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Effects of naturally occurring polyamines were tested on the activity of bovine liver nucleosidediphosphate kinase with ATP as phosphoryl donor and eight nucleosidediphosphates as phosphoryl acceptors. The enzyme was either stimulated, inhibited, or unaffected depending upon the nucleosidediphosphate substrate and the polyamine, indicating that a general cation effect is not a sole mechanism of polyamine action. This selectivity and specificity of the effects with respect to both the polyamines and the nucleosidediphosphates leads us to speculate that an action of polyamines on nucleosidediphosphate kinase may play a significant role in the regulation of specific nucleosidetriphosphate synthesis in vivo.

The effect of three naturally occurring polyamines (putrescine, spermidine, and spermine) on the activity of rabbit skeletal muscle phosphorylase phosphatase was investigated. Only spermine significantly inhibited the enzyme. The mode of inhibition (ki value of 0.3 mM) of the phosphatase by spermine appears to be different from that caused by divalent metal ions or by other organic cations, such as arginine and lysine esters, since it is noncompetitive with respect to the substrate, phosphorylase a.

Glucocorticoid receptor from rat liver was purified 1800-fold by a rapid two-step procedure using DNA-cellulose. The procedure is based on increasing the affinity of the glucocorticoid-receptor complex for DNA by heating the complex. During a first chromatography step, unheated glucocorticoid-receptor complex is separated from cytosol proteins that bind to DNA-cellulose with high affinity. During a second chromatographic step, heat-treated glucocorticoid-receptor complex is separated from proteins with low affinity for DNA. The partially purified complex is functionally competent in that it is taken up by isolated rat liver nuclei.

FEBS LettersVolume 62, Issue 3 p. 326-329 Full-length articleFree Access A second heat-stable protein inhibitor of phosphorylase phosphatase from rabbit muscle Freesia L. Huang, Freesia L. Huang Section on Physiological Controls, Laboratory of Biomedical Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20014, USASearch for more papers by this authorWalter Glinsmann, Walter Glinsmann Section on Physiological Controls, Laboratory of Biomedical Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20014, USASearch for more papers by this author Freesia L. Huang, Freesia L. Huang Section on Physiological Controls, Laboratory of Biomedical Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20014, USASearch for more papers by this authorWalter Glinsmann, Walter Glinsmann Section on Physiological Controls, Laboratory of Biomedical Sciences, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20014, USASearch for more papers by this author First published: March 01, 1976 https://doi.org/10.1016/0014-5793(76)80086-5Citations: 69AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL References 1 W. Merlevede, G.A. Riley, J. Biol. Chem., 241, (1966), 3517– 3524. 2 C.A. Chelala, H.N. Torres, Biochim. Biophys. Acta, 198, (1970), 504– 513. 3 K. Kato, J.S. Bishop, J. Biol. Chem., 247, (1972), 7420– 7429. 4 K. Kato, S. Sato, Biochim. Biophys. Acta, 358, (1974), 299– 307. 5 C. Nakai, J.A. Thomas, J. Biol. Chem., 249, (1974), 6459– 6467. 6 E.Y.C. Lee, Z.L. Capulong, S. Martin, Fed. Proc., 32, (1973), 554– 7 R.H. Haschke, L.M.G. Heilmeyer, F. Meyer, E.H. Fischer, J. Biol. Chem., 245, (1970), 6657– 6663. 8 Huang, F.L. and Glinsmann, W.H., in preparation. 9 H. Brandt, E.Y.C. Lee, S.D. Killilea, Biochem. Biophys. Res. Commun., 63, (1975), 950– 956. 10 F.L. Huang, W.H. Glinsmann, Proc. Nat. Acad. Sci. (USA), 72, (1975), 3004– 3008. 11 W.B. Wastila, J.T. Stull, S.E. Meyer, D.A. Walsh, J. Biol. Chem., 246, (1971), 1996– 2003. 12 H. Yamamura, A. Kumon, Y. Nishizuka, J. Biol. Chem., 246, (1971), 1544– 1546. 13 A.L. Shapiro, E. Viñuela, J.V. Maizel, Biochem. Biophys. Res. Comm., 28, (1967), 815– 820. 14 Nakai, C. and Glinsmann, W., in preparation. Citing Literature Volume62, Issue3March 01, 1976Pages 326-329 ReferencesRelatedInformation

DNA-cellulose chromatography was used to purify the glucocorticoid receptor from rat liver. The heat-activated [3H]-dexamethasone-receptor complex bound to DNA-cellulose in the presence of 0.1 M NaCl and could be eluted with 0.45 M NaCl. [3H]-Dexamethasone-receptor complex that had not been heat-activated did not bind to DNA-cellulose. Using a single column of DNA-cellulose the receptor could be purified 40-fold. The partially purified [3H]-dexamethasone-receptor complex was able to bind to isolated liver nuclei.

Acute hormonal regulation of fetal rat liver cyclic AMP content and glycogen phosphorylase activity was examined in an organ culture system using explants from term fetuses. Phosphorylase was rapidly activated by epinephrine and glucagon; the respective minimally effective concentrations were 2 X 10−7M and 10−8M. The characteristics of the adrenergic response were denned. Following the addition of a high concentration (10−5M) of epinephrine: Phosphorylase activity increased to a maximum at one minute (the earliest time point examined) and remained unchanged for at least 30 min; cyclic AMP levels were also maximally elevated by one minute but then declined over the next 30 min. The beta antagonist propranolol blocked both effects of epinephrine; the alpha antagonist phentolamine was without effect. The predominantly beta agonist isoproterenol was much more effective in elevating cyclic AMP levels and in activating phosphorylase than the predominantly alpha agonist phenylephrine. We conclude: i. fetal rat liver explants in organ culture offer a good in vitro model for studying acute hormonal regulation of glycogen metabolism; ii. the adrenergic receptor mediating the effects of epinephrine on fetal liver glycogen metabolism is of the beta type. (Endocrinology94: 935, 1974)

In the perfused rat liver, hyperglycemia causes a rapid inactivation of phosphorylase and a conversion of glycogen synthetase from a glucose-6-P dependent form to a glucose-6-P independent form. This effect is similar in the presence or in the absence of added insulin, but is absent following adrenalectomy and fasting when glycogen synthetase phosphatase activity is not detectable. Under conditions where phosphatase activity is low, glucose increases its activity. The effect of glucose occurs in the absence of detectable alterations in tissue concentration of adenosine 3′,5′-monophosphate, the primary intracellular regulator mediating hormonal control of the activity of these enzymes. Circulating glucose levels also directly modify the effects of glucagon on the activities of these enzymes supporting the possibility that glucose levels may be important in moderating the control of liver glycogen metabolism invivo.