Nitrogen Excretion in Ascidiacea II. Storage Excretion and the Uricolytic Enzyme System

1965 ◽  
Vol 42 (2) ◽  
pp. 299-305
Author(s):  
IVAN GOODBODY
Keyword(s):  
Uric Acid ◽  
Calcium Carbonate ◽  
Protein Metabolism ◽  
Enzyme System ◽  
Purine Metabolism ◽  
Nitrogen Excretion ◽  
Purine Base ◽  
Purine Bases ◽  
Ascidiella Aspersa

1. The evidence for the occurrence of storage excretion in ascidians is reviewed. Most species probably store uric acid or purine bases in some form. 2. The renal concretions of Ascidia nigra and Phallusia mammillata contain 50-60% uric acid, the remainder of the concretion is unidentified but is non-nitrogenous and is not calcium carbonate. In Ascidiella aspersa the concretion is predominantly composed of calcium carbonate and there is no significant quantity of uric acid or purine base. 3. Uric acid is also identified in Molgula manhattensis, Polycarpa obtecta, Pyura vittata and Herdmania momus. 4. Storage excretion probably results from a deficiency in the uricolytic enzyme system. It is concluded that while protein metabolism is ammonotelic, purine metabolism is uricotelic or xanthotelic.

Chlorogenic acid supplementation ameliorates hyperuricemia, relieves renal inflammation, and modulates intestinal homeostasis

2021 ◽  
Author(s):  
Xiaofei Zhou ◽  
Bowei Zhang ◽  
Xiuli Zhao ◽  
Yongxi Lin ◽  
Jin Wang ◽  
...  
Keyword(s):  
Uric Acid ◽  
Chlorogenic Acid ◽  
Serum Uric Acid ◽  
Inflammatory Responses ◽  
Elevated Serum ◽  
Purine Metabolism ◽  
Intestinal Homeostasis ◽  
Renal Inflammation ◽  
Acid Supplementation

Hyperuricemia (HUA) is induced by abnormal purine metabolism and elevated serum uric acid (UA) concentrations, and it is often accompanied by inflammatory responses and intestinal disorders. This study aims to...

The specificity of purine base and nucleoside uptake in promastigotes ofLeishmania braziliensis panamensis

Parasitology ◽  
1982 ◽  
Vol 85 (2) ◽  
pp. 271-282 ◽  
Author(s):  
B. D. Hansen ◽  
J. Perez-Arbelo ◽  
J. F. Walkony ◽  
L. D. Hendricks
Keyword(s):  
Competitive Interactions ◽  
Leishmania Braziliensis ◽  
Purine Base ◽  
Purine Bases ◽  
Uptake Rates ◽  
Nucleoside Uptake ◽  
And Diffusion

SUMMARYPromastigotes ofLeishmania braziliensis panamensisabsorbed the purines adenine, hypoxanthine, adenosine and inosine by a combination of diffusion and mediated components. When the uptake rates for these substrates were corrected for diffusion and compared, the purine bases adenine and hypoxanthine were transported at a significantly slower rate than the purine nucleosides adenosine and inosine. Competitive interactions among those purines tested confirmed the presence of mediated and diffusion components and suggested that three transport loci may be operating (Fig. 6). The first transport locus, designated Locus 1, transported inosine, Locus 2, the purine bases hypoxanthine and adenine and Locus 3, adenosine. In addition, adenine and hypoxanthine inhibited the uptake of one another competitively. A comparison of Kivalues derived from double reciprocal plots of labelled hypoxanthine and adenine uptake in the presence of the unlabelled substrates as inhibitors suggested that adenine has a greater affinity for the transport locus.

scholarly journals Effects of luteolin-rich chrysanthemum flower extract on purine base absorption and blood uric acid in Japanese subjects

2022 ◽  
Vol 12 (1) ◽  
pp. 12
Author(s):  
Tsuyoshi Takara ◽  
Kazuo Yamamoto ◽  
Naoko Suzuki ◽  
Shin-ichiro Yamashita ◽  
Shin-ichiro Iio ◽  
...  
Keyword(s):  
Uric Acid ◽  
Placebo Group ◽  
Serum Uric Acid ◽  
Random Number Generator ◽  
Double Blind ◽  
Japanese Men ◽  
Purine Base ◽  
Flower Extract ◽  
Before And After ◽  
Body Parameters

Background and objective: Chrysanthemum flowers are consumed as fresh condiments, herbal teas, and processed foods in Japan and Taiwan. They contain luteolin as a major polyphenol and are traditionally used for eye care. We previously demonstrated that the ingestion of Chrysanthemum flower extract (CFE) for 1 month reduced serum uric acid levels. However, the findings obtained were considered to be biased because the study was performed by a CFE manufacturer. Therefore, we herein conducted a clinical trial on CFE on a larger scale and examined its effects on purine base absorption from the intestines, which represents an effective approach for reducing serum uric acid levels. Methods: Both studies were performed as randomized, double-blind, placebo-controlled trials and CFE (100 mg) containing 1 mg of luteolin was used as the active sample. We enrolled 44 healthy Japanese men and women with 6.0 to 7.9 mg/dL serum uric acid. All subjects were randomly allocated to an active group (n=22) or placebo group (n=22) using a computerized random number generator. In the purine base absorption study, CFE was ingested with a purine base-rich diet and serum uric acid levels were measured chronologically. In the 12-week consecutive ingestion study, CFE or placebo was administered between January and April 2021. Serum uric acid levels after 12 weeks were assessed as the primary outcome, and uric acid were measured before and after 4 weeks of the intervention as secondary outcomes. Blood, urine and body parameters were examined to evaluate the safety of CFE. Results: Thirty-nine subjects completed the trial, and the per protocol set comprised 18 and 21 subjects in the active and placebo groups, respectively. In the single dosing study of CFE on subjects loaded by the purine base-rich diet, no significant changes were observed between the CFE and placebo groups. On the other hand, in the 12-week ingestion study, serum uric acid levels were significantly lower in the CFE group than in the placebo group. Laboratory tests revealed no abnormalities to suggest any side effects of CFE.Conclusions: CFE (100 mg/day) containing 1 mg of luteolin reduced serum uric acid levels. CFE may be beneficial for improving hyperurichemia. Trial Registration: UMIN-CTR: UMIN000042327Foundation: The present study was funded by Oryza Oil & Fat Chemical Co., Ltd. Keywords: Chrysanthemum, luteolin, uric acid, purine base

scholarly journals Influence of testosterone on purine metabolism and gout

2021 ◽  
Vol 22 (3) ◽  
pp. 11-17
Author(s):  
T. S. Panevin
Keyword(s):  
Uric Acid ◽  
Sex Hormones ◽  
Metabolic Disorders ◽  
Purine Metabolism ◽  
The Body ◽  
Uric Acid Concentration ◽  
Androgen Deficiency ◽  
Inflammatory Processes ◽  
High Concentrations ◽  
Pro Inflammatory Cytokines

Many different factors are involved in the regulation of purine metabolism. An important role is played by the level of sex hormones: high concentrations of androgens lead to a higher, and estrogen – to a lower level of uric acid. However, according to the results of numerous studies, it has been shown that the effect of sex hormones is not limited only to the uric acid concentration. Sex hormones affect inflammatory processes in the body by modulating the production of pro-inflammatory cytokines and regulating the corresponding signaling pathways. Androgen deficiency can lead to obesity and metabolic disorders, which can contribute to the development and course of gout. This review examines the effect of testosterone, as well as the effect of changes in its concentration on the dynamics of purine metabolism and gout.

Abstract P513: Adenylosuccinate Synthase Is A Novel Methylation Target Of Smyd1

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Magnus Creed ◽  
Marta Szulik ◽  
Ryan Bia ◽  
Chris Tracy ◽  
Aman Makaju ◽  
...  
Keyword(s):  
Heart Failure ◽  
Mass Spectrometry ◽  
Uric Acid ◽  
Purine Metabolism ◽  
Metabolic Enzyme ◽  
Mouse Heart ◽  
Lysine Methylation ◽  
Sequence Coverage ◽  
Underlying Mechanisms

Among the metabolic shifts in chronic heart failure is a dysregulation of purine metabolism, which has been shown to negatively impact patient outcomes, especially in individuals affected by hypertension, diabetes, and congestive heart failure, via increased serum uric acid levels and cellular oxidative stress. The underlying mechanisms which drive these changes in purine metabolism in the cardiomyocyte and ultimately reactive oxygen species and uric acid accumulation in heart failure patients remain largely unknown. We recently discovered that the methyltransferase Smyd1 interacts with the metabolic enzyme Adss (Adenylosuccinate synthetase), a key component of purine metabolism in the heart involved in AMP synthesis, via co-immunoprecipitation. We confirmed this novel interaction between Smyd1b and Adss in mouse heart and cultured primary cardiomyocytes, which is further enhanced during phenylephrine-induced hypertrophy in the latter. Our hypothesis was that Smyd1b methylates Adss to regulate its activity, therefore, we examined lysine methylation on Adss via western blotting and mass spectrometry and quantified its ability to convert IMP to sAMP in vitro in the presence and absence of Smyd1b. Using a pan-methylation antibody we initially detected di- and tri-methylation on Adss which was increased in the presence of Smyd1b. Then utilizing bottom-up proteomics, we achieved 98% sequence coverage of Adss via mass spectrometry and identified trimethylation on K373 only in the presence of Smyd1b. In addition, utilizing an enzymatic assay in vitro we have shown that Smyd1b enhances the activity of Adss as it converts IMP to s-AMP. While it has been well-established that the activities of metabolic enzymes are modulated via post-translational modifications (e.g. phosphorylation, acetylation), we believe this is the first report of a metabolic enzyme regulated by lysine methylation. These exciting results highlight a novel role for Smyd1b in regulating purine metabolism in the myocyte and begin to lay the groundwork for examining this mechanism in the setting of disease.

Nitrogen excretion in germ-free and conventional chickens: effects of an alkali load

1978 ◽  
Vol 39 (1) ◽  
pp. 99-104 ◽  
Author(s):  
J. Okumura ◽  
D. Hewitt ◽  
Marie E. Coates
Keyword(s):  
Amino Acids ◽  
Uric Acid ◽  
Ammonia Excretion ◽  
Nitrogen Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Total N ◽  
Germ Free ◽  
Base Balance ◽  
Micro Organisms

1. Groups of three colostomized germ-free (GF) and conventional (CV) chickens aged 4 months were maintained for successive periods of 8 d on a diet containing 200 g casein/kg without and with sodium bicarbonate at the rate of 20 mmol/d and a nitrogen-free diet without and with NaHCO3at 9 mmol/d. Urine and faeces were collected during the last 3 d of each period.2. Total N, uric acid- and ammonia-N were determined in urine and total N in faeces. Amino acids were measured in hydrolysates of faeces collected during the periods when no NaHCO3was included in the diets.3. The CV birds excreted more N on the casein diets but less on the N-free diets than did their GF counterparts, the differences being mainly shown in the urine.4. On both diets hydrolysates of the faeces of CV birds contained smaller amounts of amino acids. On the N-free diet the proportions (g/160 g N) of serine, proline and threonine were reduced, suggesting some conservation of endogenous N by micro-organisms, and the proportions of histidine, alanine, lysine and methionine increased, possibly through microbial synthesis; on the casein diet, proportions of most amino acids were less, probably because bacterial deamination had occurred.5. Urinary excretion of total N, uric acid and ammonia was much greater on the casein than on the N-free diets. Inclusion of NaHCO3caused a sharp fall in urinary ammonia on both diets and in both environments.6. It was concluded that the level of dietary protein and the regulation of acid-base balance have more effect than microbial activity on the urinary ammonia excretion.

scholarly journals The Purine Efflux Pump PbuE in Bacillus subtilis Modulates Expression of the PurR and G-Box (XptR) Regulons by Adjusting the Purine Base Pool Size

2005 ◽  
Vol 187 (2) ◽  
pp. 791-794 ◽  
Author(s):  
Per Nygaard ◽  
Hans H. Saxild
Keyword(s):  
Bacillus Subtilis ◽  
De Novo ◽  
Efflux Pump ◽  
Purine Base ◽  
Purine Bases ◽  
Purine Analogs ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Transcriptional Fusions

ABSTRACT In Bacillus subtilis, the expression of genes encoding enzymes and other proteins involved in purine de novo synthesis and salvage is affected by purine bases and phosphoribosylpyrophosphate (PRPP). The transcription of the genes belonging to the PurR regulon is negatively regulated by the PurR protein and PRPP. The expression of the genes belonging to the G-box (XptR) regulon, including the pbuE gene, is negatively regulated by a riboswitch-controlled transcription termination mechanism. The G-box regulon effector molecules are hypoxanthine and guanine. pbuE encodes a purine base efflux pump and is now recognized as belonging to a third purine regulon. The expression of the pbuE gene is positively regulated by a riboswitch that recognizes adenine. Here we show that the expression of pbuE′-lacZ transcriptional fusions are induced by adenine to the highest extent in mutants which do not express a functional PbuE pump. In a mutant defective in the metabolism of adenine, the ade apt mutant, we found a high intracellular level of adenine and constitutive high levels of PbuE. A growth test using a purine auxotroph provided further evidence for the role of PbuE in lowering the intracellular concentration of purine bases, including adenine. Purine analogs also affect the expression of pbuE, which might be of importance for the protection against toxic analogs. In a mutant that overexpresses PbuE, the expression of genes belonging to the PurR regulon was increased. Our findings provide further evidence for important functions of the PbuE protein, such as acting as a pump that lowers the purine base pool and affects the expression of the G-box and PurR regulons, including pbuE itself, and as a pump involved in protection against toxic purine base analogs.

scholarly journals The Effect of Methylxanthines on the Hypocoagulability Induced by Chloroform in the Dog

Blood ◽  
1952 ◽  
Vol 7 (4) ◽  
pp. 445-453
Author(s):  
JOHN B. FIELD ◽  
L. GRAF ◽  
KARL PAUL LINK
Keyword(s):  
Uric Acid ◽  
Liver Injury ◽  
Oral Administration ◽  
Fibrinogen Level ◽  
Protective Action ◽  
Plasma Fibrinogen ◽  
Specific Function ◽  
Plasma Fibrinogen Level ◽  
Purine Bases ◽  
Normal Functions

Abstract 1. The oral administration of a single or two consecutive daily doses of chloroform to dogs, induced hypoprothrombinemia and lowered the fibrinogen level. Both changes from the normal were most marked 48 hours after chloroform administration. By resting the dogs about 2 weeks between trials comparable reductions in the plasma prothrombin and fibrinogen levels were realized. 2. When caffeine, theobromine, theophylline and adenine were given orally to dogs prior to the oral administration of chloroform and continuing for five consecutive days, the hypoprothrombinemia was either markedly reduced or completely prevented. Creatine, creatinine, guanidine or uracil also afforded some protection. Guanine, xanthine, arginine, allantoin, uric acid or urea gave practically no protection. 3. Caffeine, theobromine, theophylline and adenine also prevented a reduction in the plasma fibrinogen level during chloroform intoxication. Uracil and guanidine showed some protective action, while creatine, creatinine, guanine, xanthine, uric acid, allantoin, urea and arginine gave no detectable protection. 4. Liver injury from the chloroform, as reflected by the bromsulfalein test and icteric plasma, was readily detectable when the methylxanthines or adenine were given with the chloroform, even though no change in prothrombin or fibrinogen level was apparent. 5. It appears that a definite relationship exists between the purine bases (caffeine, theobromine, theophylline and adenine) and the specific function of the liver to elaborate plasma prothrombin and fibrinogen. The capacity of the liver to synthesize prothrombin apparently can be affected independently of other normal functions.

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