5-hydroxytryptophan Decarboxylase Activity Research Articles

Morinda officinalis oligosaccharides increase serotonin in the brain and ameliorate depression via promoting 5-hydroxytryptophan production in the gut microbiota

Morinda officinalis oligosaccharides (MOO) are an oral drug approved in China for the treatment of depression in China. However, MOO is hardly absorbed so that their anti-depressant mechanism has not been elucidated. Here, we show that oral MOO acted on tryptophan → 5-hydroxytryptophan (5-HTP) → serotonin (5-HT) metabolic pathway in the gut microbiota. MOO could increase tryptophan hydroxylase levels in the gut microbiota which accelerated 5-HTP production from tryptophan; meanwhile, MOO inhibited 5-hydroxytryptophan decarboxylase activity, thus reduced 5-HT generation, and accumulated 5-HTP. The raised 5-HTP from the gut microbiota was absorbed to the blood, and then passed across the blood–brain barrier to improve 5-HT levels in the brain. Additionally, pentasaccharide, as one of the main components in MOO, exerted the significant anti-depressant effect through a mechanism identical to that of MOO. This study reveals for the first time that MOO can alleviate depression via increasing 5-HTP in the gut microbiota.

Further Studies on the Biosynthesis of 5-Hydroxytryptamine

Abstract The factors affecting the 5-hydroxytryptophan decarboxylase activity of the brain of animals have been studied. By altering the conditions of incubation and the amounts of the constituents of the incubation mixture, the activity as determined by the amount of 5-hydroxytryptamine formed has been increased about 10-fold. Intramuscular injections of cortisone and prednisolone did not reduce the enzyme activity although such treatment lowers the 5-hydroxytryptamine content of several tissues.

Genetic dissection of monoamine neurotransmitter synthesis in Drosophila.

The biogenic monoamine neurotransmitters octopamine, dopamine and serotonin have been detected in nervous tissue from many insects. We report here that intact Drosophila melanogaster brains, when incubated with the radioactive amino acids tyrosine and tryptophan, synthesized and accumulated labelled monoamines. In two mutant strains monoamine synthesis was abnormal. The per o mutation abolishes the normal circadian rhythm. Brains from per o flies, when incubated in tritiated tyrosine, accumulated one-third as much labelled octopamine as did brains from wild-type flies, but had normal dopamine and serotonin synthesis. In contrast, dopa decarboxylase (Ddc) mutations decreased dopamine and serotonin synthesis but did not affect octopamine synthesis. These results suggest that there are two different aromatic amino acid decarboxylases in Drosophila brains, one that decarboxylates L-dopa and 5-hydroxytryptophan and another that decarboxylates tyrosine. Direct measurement of L-dopa, 5-hydroxytryptophan and tyrosine decarboxylase activities in the different strains confirmed this suggestion.

A simple determination of serotonin, 5-hydroxyindoleacetic acid and 5-hydroxytryptophan decarboxylase activity in rat brain areas and parallel correlation among the levels.

We devised a simple method for the separation of serotonin (5HT) and 5-hydroxyindoleacetic acid (5HIAA) using small P-cellulose and DEAE-Sephadex columns, respectively. Both substances were estimated fluorometrically by the reaction with o-phthalaldehyde (OPA). In this method, some known interfering substances in addition to many primary amines and amino acids were separated from 5HT and 5HIAA. The recoveries of 5HT and 5HIAA were 80 and 71%, respectively. The fluorescence intensities of 30 pmol of 5HT and 15 pmol of 5HIAA were about twice over the reagent blank. The complete separation of 5-hydroxytryptophan (5HTP) from 5HT made it possible to determine 5HTP decarboxylase activity in rat brain areas without using an isotope-labeled substrate. The method allows for quantitation of the enzyme activity in mg amounts of the brain tissues. The activities in discrete areas were in good parallel with the 5HT contents, except for the striatum. The levels of 5HIAA were also much in parallel with those of 5HT.

A Simple Determination of Serotonin, 5-Hydroxyindoleacetic Acid and 5-Hydroxytryptophan Decarboxylase Activity in Rat Brain Areas and Parallel Correlation Among the Levels

We devised a simple method for the separation of serotonin (5HT) and 5-hydroxyindoleacetic acid (5HIAA) using small P-cellulose and DEAE-Sephadex columns, respectively. Both substances were estimated fluorometrically by the reaction with o-phthalaldehyde (OPA). In this method, some known interfering substances in addition to many primary amines and amino acids were separated from 5HT and 5HIAA. The recoveries of 5HT and 5HIAA were 80 and 71 %, respectively. The fluorescence intensities of 30 pmol of 5HT and 15 pmol of 5HIAA were about twice over the reagent blank. The complete separation of 5-hydroxytryptophan (5HTP) from 5HT made it possible to determine 5HTP decarboxylase activity in rat brain areas without using an isotope-labeled substrate. The method allows for quantitation of the enzyme activity in mg amounts of the brain tissues. The activities in discrete areas were in good parallel with the 5HT contents, except for the striatum. The levels of 5HIAA were also much in parallel with those of 5HT.

P-87 - A simple and sensitive method for the determination of serotonin, 5-hydroxyindoleacetic acid and 5-hydroxytryptophan decarboxylase activity in the areas of rat brain

P-87 - A simple and sensitive method for the determination of serotonin, 5-hydroxyindoleacetic acid and 5-hydroxytryptophan decarboxylase activity in the areas of rat brain

Twenty-four-hour variation of 5-hydroxytryptophan decarboxylase and monoamine oxidase activities in the eyestalks of the fiddler crab, UCA pugilator

1. The enzymes 5-hydroxytryptophan decarboxylase (5-HTPD) and monoamine oxidase (MAO) are present in the eyestalk of the fiddler crab, Uca pugilator. 2. Both enzymes exhibit 24-hr variation in their activities. 5-HTPD is most active at 13:00 hr in crabs maintained under a 13-hr photoperiod, lights on at 05:30 hr. MAO is most active at midnight under the same conditions. 3. These 24-hr variations are discussed in relation to the circadian rhythm of color change this crab exhibits. 4. MAO appears to be present either in more than a single form (isoenzymes) or as a single enzyme species with at least two active sites.

5-Hydroxytryptophan and Histidine Decarboxylase Activity in the Senile Cataractous Lens

5-Hydroxytryptophan and histidine decarboxylase activity (EC 4.1.1.22 and EC 4.1.1.28) in normal and senile cataractous human lenses of the same age were determined isotopically using labelled 5-hydro

Rat brain L-3,4-dihydroxyphenylalanine and l-5-hydroxytryptophan decarboxylase activities: Differential effect of 6-hydroxydopamine

Intracisternal 6-hydroxydopamine in rats pretreated with pargyline causes a marked decrease in levels of 3,4-dihydroxyphenylalanine decarboxylase in upper and lower brain stem regions 7 days post-treatment. Fifteen days after treatment with 6-hydroxydopamine, similar changes are noted in cortical areas as well. This loss of 3,4-dihydroxyphenylalanine decarboxylase activity does not temporally coincide with morphologic degeneration of nerve endings or catecholamine depletion in the various regions. 5-Hydroxytryptophan decarboxylase activity, determined on the same regional tissue, did not decrease, and even increased significantly in hypothalamus, cerebellum, and lateral medulla-pons. The disparate loss in 3,4-dihydroxyphenylalanine decarboxylase activity without corresponding loss in 5-hydroxytryptophan decarboxylase activity suggests that the two decarboxylase activities in brain tissue are catalyzed by separate, distinct proteins.

The effects of LSD on indoleamine enzymes in embryonic Xenopus laevis

1. 1. Neurulae and post-hatched Xenopus embryos were exposed to LSD at a concentration of 0.06 μg. per ml. for 6 hours. 2. 2. Monoamine oxidase (MAO) and 5-hydroxytryptophan decarboxylase (5-HTPD) activities in whole embryos were changed. 3. 3. Hydroxyindole- O-methyltransferase (HIOMT) was unchanged in whole embryos. 4. 4. MAO and 5-HTPD were unaltered in brain. 5. 5. HIOMT was altered in brains of embryos exposed to LSD at post-hatching. The level was almost zero. It was not lowered in brains of neurulae exposed to LSD. 6. 6. It is suggested that the result is a secondary effect of altered 5-HT ontogeny.

On the identity of DOPA decarboxylase and 5-hydroxytryptophan decarboxylase (immunological titration-aromatic L-amino acid decarboxylase-serotonin-dopamine-norepinephrine).

Simultaneous immunological titration of DOPA and 5-hydroxytryptophan decarboxylase activities, from a number of tissues of various species, showed that the two activities were not distinguishable with a monospecific antiserum to hog kidney decarboxylase. Together with previous findings, these data firmly establish the concept that in mammalian tissues the two enzyme activities are associated with a single protein, namely aromatic L-amino acid decarboxylase.

Effect of continuous light and darkness on hydroxyindole-0-methyltransferase and 5-hydroxytryptophan decarboxylase activities in the Japanese quail.

Hydroxyindole-O-methyltransferase (HIOMT), the melatonin forming enzyme, and 5-hydroxytryptophan decarboxylase (5- HTPD), the serotonin forming enzyme, were measured in the pineal gland (HIOMT and 5- HTPD) and hypothalamus (5-HTPD) in mature female Japanese quail maintained on a 16-hr daily photoperiod and after 5-day exposure to continuous light and darkness. HIOMT was inhibited by exposure to continuous darkness but not influenced by continuous light. Pineal 5- HTPD activity was increased by exposure to continuous darkness but not significantly decreased by exposure to continuous light. These changes in both pineal HIOMT and 5-HTPD activities in response to photoperiod are opposite to those reported in the rat. Hypothalamic 5- HTPD, also measured in the same birds, was found to be increased by exposure to both continuous light and darkness. (Endocrinology 86: 1441, 1970)

Histidine decarboxylase in gastric tissues of primates

Histidine decarboxylase activity was identified in the gastric mucosa of monkeys and man and in a human gastric carcinoid tumor. Crude homogenates of gastric mucosal tissue but not of the carcinoid tumor also demonstrated 5-hydroxytryptophan decarboxylase activity; this activity disappeared completely during purification procedures that resulted in increased specific activity of histidine decarboxylase. In all respects studied these histidine decarboxylases had properties that were very similar to or identical with histidine decarboxylases prepared from other mammalian sources: in particular, the apparent K m varied inversely with pH; the pH optimum varied inversely with substrate concentration; activity of the enzyme was enhanced by pyridoxal 5′-phosphate but not by benzene and inhibited by both brocresine and hydrazino-analog of histidine but not by α-methyl-dopa. In both monkeys and men histidine decarboxylase activity was greater in the fundus than it was in the antrum of the stomach. These findings indicate that the enzyme necessary for histamine biosynthesis is present in gastric tissues of primates and thus remove one theoretical objection to the hypothesis that histamine may mediate gastric acid secretion in primates.

5-hydroxytryptophan decarboxylase activity in the rat pineal gland during the first 20 days of postnatal life: effect of light.

The present study deals with the 5-HTPD activity in the rat pineal gland from birth up to the 20th day of life, as well as the effect of constant light or darkness from birth and of substrate administ

5-Hydroxytryptophan decarboxylase activity in monkey and rat small intestine

A comparison of the 5-hydroxytryptophan decarboxylase activity in the liver, kidney and intestine of the rat and monkey has been made. The enzyme activity is almost uniform along the length of the monkey intestine. The activity present is equally distributed between jejunum and ileum with only a small fraction in the duodenum. The relative distribution of total enzyme activity in the organs of the rat and monkey is different. The lowest activity is found in the liver in the monkey and in the intestine in the rat.

Studies on tne Significance of Metabolism of serotonin in the Allergic Reaction : Change of 5-hydroxytryptophan decarboxylase activity by the treatment of serotonin releaser and anti-allergy drug

Studies on tne Significance of Metabolism of serotonin in the Allergic Reaction : Change of 5-hydroxytryptophan decarboxylase activity by the treatment of serotonin releaser and anti-allergy drug

5-HYDROXYTRYPTOPHAN DECARBOXYLASE IN RAT BRAIN: EFFECT OF HYPOTHALAMIC LESIONS.

Section of the medial forebrain bundle within the lateral hypothalamus of the rat reduces the serotonin content and the 5-hydroxytryptophan decarboxylase activity in the brain. The integrity of this fiber tract appears necessary for the maintenance of normal concentrations of the amine and enzyme in the telencephalon.

MICRODETERMINATION OF MONOAMINE OXIDASE AND 5-HYDROXYTRYPTOPHAN DECARBOXYLASE ACTIVITIES IN NERVOUS TISSUES.

Journal of NeurochemistryVolume 12, Issue 1 p. 15-23 MICRODETERMINATION OF MONOAMINE OXIDASE AND 5-HYDROXYTRYPTOPHAN DECARBOXYLASE ACTIVITIES IN NERVOUS TISSUES R. E. McCaman, R. E. McCaman Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorM. W. McCaman, M. W. McCaman Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorJ. M. Hunt, J. M. Hunt Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorM. S. Smith, M. S. Smith Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this author R. E. McCaman, R. E. McCaman Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorM. W. McCaman, M. W. McCaman Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorJ. M. Hunt, J. M. Hunt Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this authorM. S. Smith, M. S. Smith Institute of Psychiatric Research, Indiana University School of Medicine Indianapolis, Indiana 46207Search for more papers by this author First published: January 1965 https://doi.org/10.1111/j.1471-4159.1965.tb10246.xCitations: 280Read the full textAboutPDF 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 Citing Literature Volume12, Issue1January 1965Pages 15-23 RelatedInformation

Histological and enzymatic changes in the livers of rats fed the hepatic carcinogen diethylnitrosamine

When the liver carcinogen diethylnitrosamine (DENA) was fed to Wistar rats in their drinking water over a period of 5 months, two main changes in liver structure were observed to develop in sequence: first the gradual formation of hepatomas (circumscribed nodules of highly abnormal parenchymal cells); later cholangiomas (progressive overgrowth of bile duct epithelium) which eventually dominated the histological picture. Specific and non-specific histidine decarboxylase activities were measured in livers of treated and control animals at regular intervals, the two enzymes being characterized by their Michaelis constants, pH optima, effect of benzene, and effect of inhibitors. The results indicate that the specific decarboxylase (pH 6.5) is associated with the period of hepatoma formation (maximal in excised hepatoma tissue) and not with proliferation of bile duct epithelium (cholangioma). The enzyme is thus associated with the growth of a particular cell rather than with growth in general. In the livers of both control and DENA-treated rats a highly significant positive correlation was observed between the histidine decarboxylase activity at pH 8 and the dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) decarboxylase activities; this suggests that these three activities are due to a single enzyme, a non-specific aromatic amino acid decarboxylase.

Physiological control of molluscan gill cilia by 5-hydroxytryptamine.

An examination is made of the hypothesis that endogenous 5-hydroxytryptamine (5-HT) serves as a local hormone regulating ciliary activity in the lamellibranch gill. These cilia are sensitive to exogenous 5-HT and respond to it by a prompt, sustained, and reversible rise in beat frequency; at the same time the carbohydrate metabolism is stimulated, as described elsewhere. Control gill contains small but definite amounts of endogenous 5-HT according to bioassay, fluorometry, and chromatography. The amount can be increased markedly by exposing the isolated gill to the precursor substance 5-hydroxytryptophan but not l-tryptophan. As the tissue level of 5-HT rises, the spontaneous beat frequency also rises. Both remain elevated for hours and perhaps for days. The gill of Mytilus edulis is richer than the gill of Modiolus demissus in both endogenous 5-HT and effective 5-hydroxytryptophan decarboxylase activity. Modiolus gill lacks the 5-hydroxyindole oxidase by which Mytilus gill destroys 5-HT. What if any mechanism exists in Modiolus for degrading 5-HT is not known, but monoamine oxidase is not present. The 5-HT content of Mytilus and Modiolus gill cannot be modified by treatment with reserpine or alpha-methyl-dopa. Which cells of the gill synthesize and destroy 5-HT has not been established, but these observations support the concept that the physiological activity of lamellibranch gill cilia is controlled by a serotonergic mechanism.