International congress series最新文献

{"title":"The acute tryptophan depletion and loading tests: Specificity issues","authors":"Abdulla A.-B. Badawy ,&nbsp;Christopher J. Morgan ,&nbsp;Donald M. Dougherty ,&nbsp;Dawn M. Marsh ,&nbsp;Charles W. Mathias ,&nbsp;Ashley A. Jagar ,&nbsp;Meredith A. Addicott ,&nbsp;F. Gerard Moeller","doi":"10.1016/j.ics.2007.07.021","DOIUrl":"10.1016/j.ics.2007.07.021","url":null,"abstract":"<div><p><span><span>The acute tryptophan (Trp) depletion (ATD) and loading tests are a powerful tool for examining the role of serotonin in normal subjects and in those with behavioral and other disorders. The question of how specific to serotonin the tests are, has, however, received little attention. In particular, two questions arise regarding the potential effects of the tests on </span>catecholamine synthesis, which may confound interpretation of behavioral data, namely whether: (1) the absence of Trp or its addition alters the [Phe</span> <!-->+<!--> <!-->Tyr]/[LNAA<!--> <!-->+<!--> <span><span>Trp] ratio, thereby influencing the entry of tyrosine and </span>phenylalanine into the brain; (2) the relatively larger amounts of the 3 large neutral amino acids (LNAA), namely Val, Leu and Ile, in the amino acid formulation, compared with those of Phe and Tyr, could actually decrease the above ratio. Furthermore, the [Phe</span> <!-->+<!--> <!-->Tyr]/[LNAA<!--> <!-->+<!--> <!-->Trp] and/or the [Trp]/[CAA] ratio may also be altered in control balanced and/or in Trp-loaded amino acid formulations, given the disproportionate contents of these 6 competitors in the different formulations. We addressed these questions in 114 normal US subjects divided into 5 groups of 20–25 each receiving Trp-depleted, -loaded or -balanced amino acid formulations at two dose levels: 50 g and the traditional 100 g. As expected, the [Trp]/[CAA] ratio was decreased by ATD and increased after Trp loading. However, the [Phe<!--> <!-->+<!--> <!-->Tyr]/[LNAA<!--> <!-->+<!--> <!-->Trp] ratio was also decreased by both ATD and Trp loading at both dose levels of each formulation. In subjects receiving a 50 g balanced control amino acid formulation, both the [Trp]/[CAA] and the [Phe<!--> <!-->+<!--> <!-->Tyr]/[LNAA<!--> <!-->+<!--> <span>Trp] ratios were decreased. In all cases, the above unwanted decreases were due to the relatively larger contents in the various formulations of the above 3 LNAA, compared with Phe and Tyr. Based on these results and on theoretical considerations, we suggest that by either decreasing the contents of the LNAA by up to ∼</span> <!-->30% or increasing those of Phe and Tyr by up to ∼<!--> <!-->50%, the [Phe<!--> <!-->+<!--> <!-->Tyr]/[LNAA<!--> <!-->+<!--> <!-->Trp] ratio can be maintained at normal baseline levels after consumption of the depletion, loading or balanced formulation and the [Trp]/[CAA] ratio can also be kept unaltered in the latter control formulation. We believe that this approach could achieve a greater specificity for these Trp manipulations and thus enhance the validity of the ATD and loading tests and improve interpretation of behavioral and related data.</p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 159-166"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"93386647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of tryptophan cation–pi interactions on ammonia transport through the AmtB ammonia channel","authors":"William E.C. Harries ,&nbsp;Shahram Khademi ,&nbsp;Robert M. Stroud","doi":"10.1016/j.ics.2007.07.054","DOIUrl":"10.1016/j.ics.2007.07.054","url":null,"abstract":"<div><p>The high-resolution structure of <em>Escherichia coli</em> AmtB ammonia/ammonium channel and proteoliposome functional analysis has provided sufficient information to propose a permeation theory for this integral membrane channel protein. The role of cation–pi interactions at the periplasmic vestibule of the channel is proposed and integrated with molecular and quantum mechanical dynamics simulations and calculations. The structural and simulation data closely reinforce each other and point to cation–pi interactions as one of the primary mechanisms of ligand recruitment within the channel vestibule.</p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 15-21"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.054","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"110892606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pharmacology of the kynurenine pathway","authors":"Trevor W. Stone ,&nbsp;L. Gail Darlington","doi":"10.1016/j.ics.2007.07.013","DOIUrl":"10.1016/j.ics.2007.07.013","url":null,"abstract":"<div><p><span><span>The kynurenine<span><span> pathway of tryptophan </span>oxidative metabolism<span> plays a major role in the nervous and immune systems and has been implicated in a range of disease states. Much of the interest in the pathway has been centred around the role of quinolinic acid as an agonist at </span></span></span>glutamate receptors sensitive to </span><em>N</em>-methyl-<span>d</span><span>-aspartate (NMDA) and kynurenic acid<span><span> which blocks all the ionotropic glutamate receptors. In addition, it is clear that the pathway is important in modulating the level of oxidative stress in tissues, partly via the activation of blockade of NMDA receptors, but also via the generation of redox active compounds such as 3-hydroxykynurenine and 3-hydroxyanthranilic acid. Pharmacological interference with this pathway therefore presents a route for reducing oxidative tissue damage at several different metabolic steps, providing a valuable potential therapeutic target for new </span>drug development.</span></span></p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 298-304"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"99816757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tumoral immune resistance based on tryptophan degradation by indoleamine 2,3-dioxygenase","authors":"B.J. Van den Eynde,&nbsp;I. Théate,&nbsp;C. Uyttenhove,&nbsp;D. Colau,&nbsp;L. Pilotte,&nbsp;V. Stroobant","doi":"10.1016/j.ics.2007.07.043","DOIUrl":"10.1016/j.ics.2007.07.043","url":null,"abstract":"<div><p><span><span>Tumor cells constitutively express indoleamine 2,3-dioxygenase (IDO), which degrades tryptophan and lowers tryptophan concentration in the local microenvironment. Such altered microenvironment protects tumor cells from rejection by the immune system, as </span>T lymphocytes<span><span> are exquisitely sensitive to tryptophan shortage. This may explain the low clinical efficacy of cancer immunotherapy based on vaccination. </span>Preclinical studies indicate that this immune resistance mechanism can be blocked by systemic delivery of a pharmacological IDO inhibitor, 1-methyl-</span></span><span>l</span><span>-tryptophan. These results suggest the clinical efficacy of cancer immunotherapy can be boosted by combined treatment of cancer patients with an IDO inhibitor.</span></p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 274-277"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.043","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"103989976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of dietary tryptophan metabolism on the “vigor” and “confusion” factor of mood","authors":"Reiko Yonekura ,&nbsp;Yasuhiro Itoh ,&nbsp;Masami Asayama ,&nbsp;Katsumi Shibata","doi":"10.1016/j.ics.2007.07.028","DOIUrl":"10.1016/j.ics.2007.07.028","url":null,"abstract":"<div><p><span><span>Previously, we reported that tryptophan metabolites affect mood. According to research conducted using the </span>Profile of Mood States<span><span><span> (POMS) test, kynurenin and serotonin, which are intermediary metabolites of tryptophan, appear to be correlated with some factors of mood. The present study examined one of the tryptophan metabolites that affects mood using a nutritional method. According to the results of the POMS-test and the </span>nutrition survey, the “vigor” and “confusion” factors of mood were correlated with the intake of tryptophan and </span>niacin. In contrast, serum tryptophan and kynurenin were correlated resting conditions (</span></span><em>r</em> <!-->=<!--> <!-->0.872). Furthermore, correlations were observed between “vigor” and serum kynurenin (<em>r</em> <!-->=<!--> <!-->0.597) and between “confusion” and serum kynurenin (<em>r</em> <!-->=<!--> <!-->0.681).</p><p>These findings indicate a positive relationship between the intake of tryptophan and niacin and emotional state. Therefore, we investigated the relationship between intake values of tryptophan, niacin and each mood. The observed intake of tryptophan was 610<!--> <!-->±<!--> <!-->134 mg/day, while the intake of niacin was 13<!--> <!-->±<!--> <!-->4 mg/day. Correlations were observed between intake of tryptophan and “confusion”(r<!--> <!-->=<!--> <!-->−<!--> <!-->0.602) and “vigor”(<em>r</em> <!-->=<!--> <!-->0.727), and between the intake of niacin and “confusion” (<em>r</em> <!-->=<!--> <!-->−<!--> <!-->0.786) and “vigor”(<em>r</em> <!-->=<!--> <!-->0.585).</p><p>These results suggest that dietary intake of tryptophan and niacin is correlated to tryptophan metabolites and mood. In particular, we suggest that the correlation between serum tryptophan, kynurenin and observed resting conditions of “vigor” and “confusion” resulted from dietary intake of tryptophan.</p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 180-183"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.028","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"96003098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Induction of indoleamine 2,3-dioxygenase in small intestine of mouse infected with parasitic helminth, Hymenolepis nana","authors":"F. Ohyama ,&nbsp;S. Tone ,&nbsp;T. Okamoto ,&nbsp;K. Shimoda ,&nbsp;Y. Minatogawa","doi":"10.1016/j.ics.2007.07.051","DOIUrl":"10.1016/j.ics.2007.07.051","url":null,"abstract":"<div><p>One hundred and fifty crushed eggs of <span><em>Hymenolepis nana</em></span><span> were administrated to 5–6 week old ddY mice<span><span>, and the animals were killed at 0, 7, 14, 21 or 28 days post-infection (dpi). The small intestines were recovered, and both halves, proximal and distal, were examined, observed for </span>immunohistochemistry<span>, and assayed on enzyme activity<span> of IDO. Enzyme activity of IDO was increased by </span></span></span></span><em>H. nana</em><span> infection, and was parallel to a decrease of recovered worms. The expression pattern of IDO-positive cells in the proximal intestine was also the same as those of IDO activity with a little change earlier. Furthermore, IDO-positive cells coincided with goblet cells, but not all goblet cells were IDO-positive. Present findings apparently suggest that IDO might be involved in the mucous excretion process in the expulsion of worms.</span></p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 286-289"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.051","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"105212199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effect of tryptophan on quarrelsomeness, agreeableness, and mood in everyday life","authors":"Simon N. Young ,&nbsp;Marije aan het Rot ,&nbsp;Gilbert Pinard ,&nbsp;Debbie S. Moskowitz","doi":"10.1016/j.ics.2007.07.037","DOIUrl":"10.1016/j.ics.2007.07.037","url":null,"abstract":"<div><p>In humans there is an association between low serotonin levels and aggressive behavior, and drugs that increase serotonin function have been used to treat aggression. In monkey alterations in serotonin function seem to influence behavior along the agonistic–affiliative axis, with increases in serotonin function not only decreasing aggression but also increasing the grooming of other animals. Measurement of human social behavior in everyday life has advanced to the stage where it is possible to measure behavior along the agreeable–quarrelsome axis. Therefore we performed two double-blind cross-over studies to compare the effects of tryptophan, the serotonin precursor, with placebo on the social behavior of healthy people. In the first study tryptophan decreased quarrelsome behaviors. In the second study on irritable people tryptophan not only decreased quarrelsome behaviors but also increased agreeable behaviors and improved mood. Our studies suggest that increasing serotonin synthesis with tryptophan moves behavior along the axis that encompasses aggressive, quarrelsome, and agreeable behaviors towards more positive social behavior in healthy people in everyday life. Irritability is a risk factor for various mental and physical disorders. It remains to be seen whether increasing serotonin function in irritable people improves their mental and physical health.</p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 133-143"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.037","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109098283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary fat and peroxisome-proliferators affect production of quinolinate in rats, accompanied with suppression of gene expression of α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD)","authors":"Yukari Egashira ,&nbsp;Hiroyuki Hashimato ,&nbsp;Kuniaki Saito ,&nbsp;Hiroo Sanada","doi":"10.1016/j.ics.2007.07.030","DOIUrl":"10.1016/j.ics.2007.07.030","url":null,"abstract":"<div><p><span>Hepatic α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase<span><span> (ACMSD) plays a key role in regulating NAD biosynthesis<span> from tryptophan. ACMSD also seems to affect the generation of </span></span>quinolinic acid<span> (QA), a neurotoxin </span></span></span><span>l</span><span>-tryptophan metabolite. QA is also a potential endogenous toxin. The aim of this study was to evaluate QA concentration and ACMSD mRNA expression after dietary fat<span><span><span> or peroxisome-proliferator ingestion. When male Sprague–Dawley rats were fed a clofibrate-free diet (control), or a clofibrate-containing diet for 8 days, hepatic ACMSD mRNA in rats consuming the </span>clofibrate diet was strongly suppressed, as compared with that fed the control. Shifting from the control diet to a clofibrate diet suppressed ACMSD mRNA strongly at day 1 and continued through day 4. However, ACMSD activity decreased gradually. In rats fed with several kinds of peroxisome-proliferator-containing diets, the hepatic ACMSD mRNA was drastically decreased by all the peroxisome-proliferators we used. On the other hand, </span>linoleic acid<span>, clofibrate, bezafibrate and Wy-14,643 affected the serum QA levels. The change of serum QA concentration after peroxisome-proliferator ingestion is suggested to be, in part, due to a decreased ACMSD gene expression. These results suggest that the ingestion of peroxisome-proliferators affect serum QA concentration and that the transcription level of hepatic ACMSD is modulated by peroxisome-proliferators.</span></span></span></p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 195-199"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"110298418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proteomic analysis of 6-nitrotryptophan-containing proteins in peroxynitrite-treated PC12 cells","authors":"Keiichi Ikeda ,&nbsp;Hideaki Iwai ,&nbsp;Takashi Matsumoto ,&nbsp;Reiko Mineki ,&nbsp;Hikari Taka ,&nbsp;Kenji Takamori ,&nbsp;Hideoki Ogawa ,&nbsp;Fumiyuki Yamakura","doi":"10.1016/j.ics.2007.07.036","DOIUrl":"10.1016/j.ics.2007.07.036","url":null,"abstract":"<div><p><span>We identified 6-nitrotryptophan-containing proteins in peroxynitrite-treated PC12 cell<span>, a neuron-like cell, by proteomic<span> analysis using a specific polyclonal antibody which we have developed by using 6-nitrotryptophan-containing </span></span></span>synthetic peptides<span><span> as an antigen. Western blot analysis showed nine immunoreactive spots of newly appeared or significantly increased signals in the peroxynitrite-treated cells compared with that of the untreated cells in two-dimensional gel electrophoresis. We analyzed the proteins corresponding to these spots by trypsin digestion and LC-MS/MS. These spots contained seven proteins such as M2 </span>pyruvate kinase<span><span>, mitochondrial aconitase<span> 2, eukaryotic translation elongation factor 2, </span></span>pyruvate carboxylase<span>, sarcosine dehydrogenase<span>, vinculin<span> and heat-shock protein 90α. Several proteins contained functional tryptophan<span> residues that interact with other molecules. We speculate that the nitration of tryptophan residues in the neuron-like cell during neuroinflammation<span> may affect cellular energy metabolism, protein synthesis, and stress response and may modulate the specific interaction of proteins with other molecules.</span></span></span></span></span></span></span></p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 33-40"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.036","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"101941966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-protein (free and protein-bound) tryptophan content in cereal and legume seed flours","authors":"S. Comai ,&nbsp;A. Bertazzo ,&nbsp;L. Bailoni ,&nbsp;M. Zancato ,&nbsp;C.V.L. Costa ,&nbsp;G. Allegri","doi":"10.1016/j.ics.2007.07.007","DOIUrl":"10.1016/j.ics.2007.07.007","url":null,"abstract":"<div><p><span>Cereals and legumes are the major source of protein in the human diet. There is little information on the presence of non-protein tryptophan, one of the essential </span>amino acids<span><span> less represented in the vegetable proteins. Our results show that tryptophan is present not only in the free-form but also is linked either to water soluble proteins<span> or to proteins extracted at pH 8.9 both in cereal and legume flours. As regards the cereals, wheat and spelt contain the highest content of protein tryptophan and maize the lowest. Spelt, followed by barley and pearl millet flours, contains the highest amounts of free tryptophan and the rice the lowest. In addition, spelt flour shows the highest levels of tryptophan linked to both water soluble and buffered protein fractions, whereas rice contains the lowest amounts of protein-bound tryptophan. Among the legume flours, soybeans show the highest value in protein tryptophan and peas the lowest. Chick peas contain the highest concentrations of both free and protein-bound tryptophan water soluble fraction. This last fraction appears absent in </span></span>broad bean, lentil and soybean flours. In addition, beans are shown to contain the highest levels of tryptophan linked to proteins extracted at pH 8.9, and peanuts the lowest values both as free and protein-bound forms.</span></p><p>Considering that tryptophan is one of the limiting amino acids of the biological value of vegetable proteins, the determination of non-protein tryptophan in food is very useful in calculating the score.</p></div>","PeriodicalId":84918,"journal":{"name":"International congress series","volume":"1304 ","pages":"Pages 227-232"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.ics.2007.07.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"96902369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}