Amino acids, Urinary

Hyperargininemia. This defect is characterized by elevated blood and cerebrospinal fluid arginine levels, low erythrocyte levels of arginase (reaction 5, Figure 29-9), and a urinary amino acid pattern resembling that of lysine-cystinuria. This pattern may reflect competition by arginine with lysine and cystine for reabsorption in the renal tubule. A low-protein diet lowers plasma ammonia levels and abolishes lysine-cystinuria. 

Hendriks, W.H., Moughan, P.J., Tarttelin, M.F. and Woolhouse, A.D. (1995b) Felinine a urinary amino acid of Felidae. Comp. Biochem. Physiol. B Biochem. Mol. Biol. 112, 581-588. 

In some cases, the amino acid pattern on a paper chromatogram is very similar to that found in diseases of the renal tubules, such as cystinosis, where there is a failure to reabsorb all amino acids from the glomerular filtrate and, in consequence, the urinary amino acid pattern resembles that of plasma (W6, W9). In other cases the aminoaciduria is less marked and the amino acids found in greatest excess are glycine, alanine, serine, threonine, and glutamine. In some cases no aminoaciduria has been detected. 

The urinary amino acids reflect both their high concentration in the blood, due to poor functioning of the liver, and failure of renal tubular reabsorption. The phenolic acids and tyrosine in the urine are evidence... 

Stein et al. found in the course of experiments dealing with free and conjugated urinary amino acids in Wilson s disease (S9) that besides a marked aminoaciduria, almost a twofold increase in the excretion of all bound amino acids could be observed. As compared with normal urine (S8), unusual amounts of conjugated leucine, isoleucine, and valine are excreted in cases of Wilson s disease. Also the increase of glutamic acid, aspartic acid, and phenylalanine after urine hydrolysis is much more distinct in this disease than in normal conditions. Other bound amino acids are at or below normal levels. 

Table 2.1.10 Unusual (mainly urinary) amino acids and related substances that may be encountered in metabolic disease. The position of the neighboring components is not always well defined for each instrument, therefore the analytical biochemist will try and collect as many reference substances as possible ... 

Table 2.1.10 (continued) Unusual (mainly urinary) amino acids and related substances that may be encountered in metabolic disease. 

Parvy P, Bardet J, Rabier D, Kamoun P (1995) A scheme for the interpretation of primary and secondary disturbances of plasma and urinary amino acid profiles. A possible way to an expert system. Clin Chim Acta 235 1-10... 

Free Urinary Amino Acids of Healthy Adults (mM X 102/24 hour collection) < ... 

Fic. 2. Chromatogram of normal adult female subject (urinary amino acids, daily output at mid-cycle 1,010 ml/24 hr sample 2 ml). Elution curve from Dowex 50-X5 of free amino acids and closely related substances. Peaks Xu X2 and Yj, Y2 are found regularly but correspond to unknown substances they do not disappear after hydrolysis. The peak marked peptide in the region near fraction 410 is usually present and disappears after hydrolysis. The one at fraction 325 also disappears after hydrolysis, but its presence was seen only once in a group of more than 50 different samples of urines of normal subjects, including cases of pregnancy (Soupart, footnote p. 223). Amino acids in brackets are usually found but were practically absent from die present sample of urine. 

A12. Awapara, J., and Sato, Y., Paper chromatography of urinary amino acids. Clin. Chim. Acta 1, 75-79 (1956). 

Since D-amino acids are poorly utilized, diets containing sufficient quantities of D-enanticmers will result in elevated levels of plasma and urinary amino acids. Urinary excretion of D-methionine by infants fed a formula supplemented with DD-methionine has led to misdiagnosis of inborn errors of metabolism (77). D-Amino acids derived from processed food proteins may confuse medical diagnoses. Determining D-amino acid contents of caimon foods would estimate the significance of this problem. Some preliminary results are shown in Table VI. 

The Hartnup disease described in 1956 (B2) under the title hereditary pellagra-like skin rash with temporary cerebellar ataxia, constant renal aminoaciduria, and other bizarre biochemical features evidently belongs to the diseases related to inborn errors of metabolism due to inherited differences. As was pointed out by Harris (H3), very often the detection of urinary amino acid metabolites has represented the starting point of the investigation of different genetic biochemical disorders. A recent study (A8) showed that the excess production of indole by colon bacteria in 15 cases of Hartnup disease was due entirely to an increased amount of tryptophan contained in the large bowel, and not to an abnormality of the bacteria themselves. 

Vigabatrin can produce an abnormal urinary amino acid pattern, which can be diagnostically confusing (SEDA-16, 74). It increases plasma and urinary alpha-aminoadipic acid concentrations, possibly comphcating the diagnosis of alpha-aminoadipicaciduria (SEDA-20, 71). 

Hara K, Hijikata Y, Hiraoka E, et al. Measurement of urinary amino acids using high-performance liquid chromatography equipped with a strong cation exchange resin pre-column. Ann Clin Biochem 1999 36 202-6. 

In hyperammonemia, however, there is no single large preponderant ninhydrin-positive band of amino acid visible after paper chromatography and the pattern of urinary amino acid found on chromatography may appear to be normal or nearly so. However, the glutamine band is usually more than normally prominent. Confirmation is by a quantitative ion exchange chromatography as below, which will also reveal the increased excretion of alanine. 

A5. Ambert, J., Pechery, C., and Carpentier, C., Estimation of urinary amino acids. 1. In the normal subject. (Technique of electrophoresis at pH 5.4, two-dimensional chromatography on silica gel thin layers and electrochromatography.) Ann. Biol. Clin. (Paris) 24, 17-40 (1966). 

F15. Frentz, R., Thin-layer chromatography of urinary amino acids. Ann. Biol. Clin. Paris) 23, 1145-1155 (1965). 

H12. Holmgren, G., Jeppsson, J. 0., and Samuelson, G., High-voltage electrophoresis in urinary amino acid screening. Scand. J. Clin. Lah. Invest. 26, 313-318 (1970). 

Oeriu, S., and TSnase, I., Separation of urinary amino acids in various normal and pathologic conditions by equilibrium paper chromatography. Rev. Roum. Physiol. 4, 47-49 (1967). 

T6. Troughton, W. D., Brown, E. St. C., and Turner, N. A., Separation of urinary amino acids by thin-layer high voltage electrophoresis and chromatography. Amer. J. Clin. Pathol. 46, 139-143 (1966). 

H18. Hurley, K. E., and Williams, R. J., Urinary amino acids, creatine and phosphate in muscular dystrophy. Arch. Biochem. Biophys. 64, 384-391 (1955). 

Hubbard R, Haddad E, Berk L, Peters W, Tan S. Urinary amino-acid level differences between adult human omnivores and vegans. FASEB J 1994 8(4)rA464-A464. 

Carver M J and Paska R. (1961) Ion-exchange chromatography of urinary amino acids. Clm Chim Acta 6, 721-724... 

Chauhan J, Darbre A, and Carlyle R. F (1982) Determination of urinary amino acids by means of glass capillary gas-liquid chromatography with alkali-flame ionization detection and flame lonizaton detection / Chromatogr 227, 305-321... 

For urinary amino adds [22], 0.5 ml of urine was mixed with 0.5 ml of 0.5 M sodium bicarbonate and 2 ml of DABSCl (2 g P in acetone). The reaction mixture was maintained at pH 8.5-9.0 and 25-26 "C for 30 min. The filtrates were directly applied to a Cjg column for HPLC separation. Interfering amino compounds present in the urine also form derivatives with DABSQ, but may be removed by extraction with chloroform. Ammonia reacts readily with DABSCl, resulting in a derivative coeluted with DABS-methionine. Furthermore, ammonia may consume so much DABSCl that it seriously interferes with the derivatization of amino acids. Therefore the ammonia should be removed by lyophilizing the samples at pH 8.9 before derivatization. This method allowed the detection of urinary amino acid down to concentrations of about 16mgl ... 

Kent E. Matsumoto, David H. Partridge, Arthur B. Robinson, Linus Pauling, Robert A. Flath, T. Richard Mon, and Roy Teranishi). The process of aging. In New Dynamics of Preventive Medicine, Vol. 3, Leon R. Pomeroy, ed., Symposia Specialists, Miami, FL, (1974), pp. 107—113. Sex-related patterns in the profiles of human urinary amino acids. Clin. Chem. 21 (1975) 1970—1975. (Henri Dirren, Arthur B. Robinson, and Linus Pauling). 

Ethylalanine excretion can be reversed by administering methionine therefore, increased excretion of ethylalanine appears to result from the lack of methyl groups. The total urinary nitrogen content is increased in patients with kwashiorkor. This results from increased levels of urinary amino acids. But the increase in urinary amino acid cannot explain the overall increase in urinary nitrogen, and it has been suggested that part of this increase results from increased purine excretion. The structure of the excreted purine is not known. 

Plasma and urinary amino acids in primary gout, with special reference to glutamine. J. Clin. Invest. 48 885. 

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