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Determination of erythrocyte uroporphyrinogen I synthetase activity in chronic renal failure
241
Clinica Chimica Acfa, 104 (1980) 241-244 0 Elsevier/North-Holland Biomedical Press
SHORT COMMUNICATION CCA 1347
DETERMINATION OF ERYTHROCYTE UROPORPHYRINOGEN SYNTHETASE ACTIVITY IN CHRONIC RENAL FAILURE
A. ANDRIOLO, Nephrology (Received
A.J. MOCELIN
*, S.R. STELLA,
H. AJZEN
Division, Escola Paul&a de Medicina, So June 29th,
I
and O.L. RAMOS
Paul0 (Bra&)
1979)
Summary To obtain some information on porphyrin metabolism in uraemic patients, the activity of erythrocyte uroporphyrinogen I synthetase was measured in patients with chronic renal failure. The results indicate a decreased enzymatic activity which is not due to urea interference, in the hemolysates of these patients.
Introduction Little is known of porphyrin metabolism in uraemic patients, despite evidence showing that medium-sized molecules (300 to 2000 molecular weight) can influence important steps in hemoglobin synthesis. We have studied some of these steps in patients with chronic renal failure of different etiologies
[W.
Uroporphyrinogen I synthetase, URO-S (EC 4.3.1.8) catalyzes the conversion of porphobilinogen (PBG) to urobilinogen I. The measurement of URO-S activity in red blood cell hemolysates is useful in the diagnosis of acute intermittent porphyria [ 3,4,5], but it also provides information about the status of porphyrin synthesis in other conditions. In this paper we present our results concerning URO-S activity in erythrocytes of uraemic patients. Material and methods The determination of erythrocyte URO-S activity was carried out according to Mandel [6 1. Normal values were obtained from 11 non-uraemic healthy * To whom correspondence
should be addressed.
242 TABLE I AGE, SEX. HEMATOLOGIC AND RENAL FUNCTION STATUS OF 11 CONTROLS RENAL FAILURE PATIENTS SUBMITTED TO UROS DETERMINATION Case
No.
Age
St?X
(years)
RBC (x10.5)
Serum creatinine (mg/dII
Controls 01 02 03 04 05 06 01 08 09 10 11
40 39 18 20 23 49 32 26 38 34 42
M F M M F F M M M F M
4.1 5.0 5.2 4.9 4.6 4.5 4.5 5.1 4.5 4.9 5.0
1.0 0.9 0.9 1.0 0.8 0.8 1.1 1.0 0.9 1.0 1.0
Uraemics 01 02 03 04 05 06 01 00 09 10 11
42 38 59 45 52 43 36 33 40 48 37
M M F M M M M F F M M
3.2 1.6 3.3 3.3 3.3
8.3 7.4 7.0 13.4 7.8 10.6 8.3 10.9 7.7 6.3 9.1
3.2 3.2 2.6 3.3 2.8 3.2
AND 11 CHRONIC
M, male; F, female; RCC. red blood cells.
TABLE II URO-S ACTIVITY
IN THE ERYTHROCYTES
(run01 PBG consumed/min/lOg Case No.
Control
Uraemics
01 02 03 04 05 06 07 08 09 10 11
0.99 1.13 0.91 0.88 0.96 0.68 1.13 0.74 0.96 1.02 0.16
0.52 0.54 0.58 0.84 0.68 0.61 0.59 0.68 0.61 0.88 0.95
Average S.D.
0.92 0.15
0.69 0.14
P < 0.002.
OF 11 CONTROLS
erythrocytes at 45’C)
AND 11 URAEMIC
PATIENTS
243
adults. The study group was composed of 11 adults with chronic uraemia, attending the Nephrology Section of the Escola Paulista de Medicina. All were haemodialyzed three times a week (Travenol, 1 msq) and the blood samples were collected just before treatment. Table I shows their age, sex, hematologic and renal function data. Results The control value for URO-S activity was 0.92 (SD. = 0.15) nmol PBG consumed/min/lOg erythrocytes at 45°C. This agrees closely with control values reported by others [7-91. As Table II shows, there is a decreased enzymic activity in the erythrocytes of uraemia patients; the results are similar to those of Leber et al. [lo]. Discussion Previous work [1,2,10] has provided evidence that uraemic patients have higher plasma concentrations of delta-~~ole~lini~ acid and porphobilinogen than subjects with normal renal function. In this study we found a decreased activity of the enzymic system involved in the normal metabolism of these substances. Goubeaud and Leber [11,12] showed that an undetermined substance of middle molecular weight range isolated from uraemic patients and not present in normal serum, causes a marked inhibition of globin and porphyrin synthesis. Blum et al. [S] suggested that the decreased enzymic activity could be a technical artifact caused by interference by high urea levels. This does not seem to be the case since the method used by us to determine URO-S involves two readings, one taken with and one without incubation and the enzymic activity is taken as the difference between the two. Considering this fact, we think that in patients with chronic renal failure, biochemical alterations occur as a result of the retention of deleterious compounds which could block this enzymic pathway. Further investigations are needed in order to explain whether these alterations could, at least partially, be responsible for the observed depression of erythropoiesis in chronic renal failure. References 1
2 3 4 5 6 7 8 9
A.. Mocelin, A.J.. Pereira. A.B., Lima, M.C.C., Schor, N. and Ramos, O.L. (1978) IX Congr. Bras. Nefrologia. Oct. 15-20, Rio de Janeiro-RJ (Abstract) Mocelin, A.J.. Andriolo, A., Pereira, A.B., Stella, S.R., Gelman. A. and Ajzen, H. (1978) IX Congr. Bras. Nefrologia, Oct. 15-20, Rio de Janeiro-RJ Strand, L.J., Felsher, B.F.. Redeker, A.G. and Marver, H.S. (1970) Proc. N&l. Acad. Sci. USA 67. 1315-1320 Peterson, L.R., Hamernuik, P.. Bird, T.D. and Labbe. R.F. (1976) Cfin. Chem. 22.1835-1840 Magnussen, C.R.. Levi% J.B., Doherty. J.M., Cheesman, J.O. and Tchudy, D.P. (1974) Blood 44, 857-868 Mandel. P., Koehl, C. and Werthenschlag, J. (1974) Ann. Biol. Clin. 32, 353-358 Piepkorn. M.W., Hamemyik, P. and Labbe. R.F. (1978) Clin. Chem. 24/10,1751-1754 Blum, M., Koehl, C. and Abecassis. 3. (1978) Clin. Cbim. Acta 87, 119-125 GrandchamP, B., Phung, N’G., Grelier, M. and Nordmann, Y. (1976) Clin. Chim. Acta 70. 113-118 Andriolo,
244 10 Leber. H.. Sinning, P. and Schutterle. G. (1974) Proc. Eur. Dial. Transplant. ASSOC.11. 383-390 11 Goubeaud. G., Leber. H.W.. Schott. H.H., Schutterle. G. (1976) XIII Congr. Eur. Dial. Transplant Assoc. Hamburg, Germany, June 22-25. pp. 37 12 Leber. H.W.. Neuhauser. M.. Goubeaud, G.. Schutterle, G. (1976) XIII Congr. Eur. Dial. Transplant Assoc. Hamburg, Germany. June, 22-25, PP. 265
Clinica Chimica Acfa, 104 (1980) 241-244 0 Elsevier/North-Holland Biomedical Press
SHORT COMMUNICATION CCA 1347
DETERMINATION OF ERYTHROCYTE UROPORPHYRINOGEN SYNTHETASE ACTIVITY IN CHRONIC RENAL FAILURE
A. ANDRIOLO, Nephrology (Received
A.J. MOCELIN
*, S.R. STELLA,
H. AJZEN
Division, Escola Paul&a de Medicina, So June 29th,
I
and O.L. RAMOS
Paul0 (Bra&)
1979)
Summary To obtain some information on porphyrin metabolism in uraemic patients, the activity of erythrocyte uroporphyrinogen I synthetase was measured in patients with chronic renal failure. The results indicate a decreased enzymatic activity which is not due to urea interference, in the hemolysates of these patients.
Introduction Little is known of porphyrin metabolism in uraemic patients, despite evidence showing that medium-sized molecules (300 to 2000 molecular weight) can influence important steps in hemoglobin synthesis. We have studied some of these steps in patients with chronic renal failure of different etiologies
[W.
Uroporphyrinogen I synthetase, URO-S (EC 4.3.1.8) catalyzes the conversion of porphobilinogen (PBG) to urobilinogen I. The measurement of URO-S activity in red blood cell hemolysates is useful in the diagnosis of acute intermittent porphyria [ 3,4,5], but it also provides information about the status of porphyrin synthesis in other conditions. In this paper we present our results concerning URO-S activity in erythrocytes of uraemic patients. Material and methods The determination of erythrocyte URO-S activity was carried out according to Mandel [6 1. Normal values were obtained from 11 non-uraemic healthy * To whom correspondence
should be addressed.
242 TABLE I AGE, SEX. HEMATOLOGIC AND RENAL FUNCTION STATUS OF 11 CONTROLS RENAL FAILURE PATIENTS SUBMITTED TO UROS DETERMINATION Case
No.
Age
St?X
(years)
RBC (x10.5)
Serum creatinine (mg/dII
Controls 01 02 03 04 05 06 01 08 09 10 11
40 39 18 20 23 49 32 26 38 34 42
M F M M F F M M M F M
4.1 5.0 5.2 4.9 4.6 4.5 4.5 5.1 4.5 4.9 5.0
1.0 0.9 0.9 1.0 0.8 0.8 1.1 1.0 0.9 1.0 1.0
Uraemics 01 02 03 04 05 06 01 00 09 10 11
42 38 59 45 52 43 36 33 40 48 37
M M F M M M M F F M M
3.2 1.6 3.3 3.3 3.3
8.3 7.4 7.0 13.4 7.8 10.6 8.3 10.9 7.7 6.3 9.1
3.2 3.2 2.6 3.3 2.8 3.2
AND 11 CHRONIC
M, male; F, female; RCC. red blood cells.
TABLE II URO-S ACTIVITY
IN THE ERYTHROCYTES
(run01 PBG consumed/min/lOg Case No.
Control
Uraemics
01 02 03 04 05 06 07 08 09 10 11
0.99 1.13 0.91 0.88 0.96 0.68 1.13 0.74 0.96 1.02 0.16
0.52 0.54 0.58 0.84 0.68 0.61 0.59 0.68 0.61 0.88 0.95
Average S.D.
0.92 0.15
0.69 0.14
P < 0.002.
OF 11 CONTROLS
erythrocytes at 45’C)
AND 11 URAEMIC
PATIENTS
243
adults. The study group was composed of 11 adults with chronic uraemia, attending the Nephrology Section of the Escola Paulista de Medicina. All were haemodialyzed three times a week (Travenol, 1 msq) and the blood samples were collected just before treatment. Table I shows their age, sex, hematologic and renal function data. Results The control value for URO-S activity was 0.92 (SD. = 0.15) nmol PBG consumed/min/lOg erythrocytes at 45°C. This agrees closely with control values reported by others [7-91. As Table II shows, there is a decreased enzymic activity in the erythrocytes of uraemia patients; the results are similar to those of Leber et al. [lo]. Discussion Previous work [1,2,10] has provided evidence that uraemic patients have higher plasma concentrations of delta-~~ole~lini~ acid and porphobilinogen than subjects with normal renal function. In this study we found a decreased activity of the enzymic system involved in the normal metabolism of these substances. Goubeaud and Leber [11,12] showed that an undetermined substance of middle molecular weight range isolated from uraemic patients and not present in normal serum, causes a marked inhibition of globin and porphyrin synthesis. Blum et al. [S] suggested that the decreased enzymic activity could be a technical artifact caused by interference by high urea levels. This does not seem to be the case since the method used by us to determine URO-S involves two readings, one taken with and one without incubation and the enzymic activity is taken as the difference between the two. Considering this fact, we think that in patients with chronic renal failure, biochemical alterations occur as a result of the retention of deleterious compounds which could block this enzymic pathway. Further investigations are needed in order to explain whether these alterations could, at least partially, be responsible for the observed depression of erythropoiesis in chronic renal failure. References 1
2 3 4 5 6 7 8 9
A.. Mocelin, A.J.. Pereira. A.B., Lima, M.C.C., Schor, N. and Ramos, O.L. (1978) IX Congr. Bras. Nefrologia. Oct. 15-20, Rio de Janeiro-RJ (Abstract) Mocelin, A.J.. Andriolo, A., Pereira, A.B., Stella, S.R., Gelman. A. and Ajzen, H. (1978) IX Congr. Bras. Nefrologia, Oct. 15-20, Rio de Janeiro-RJ Strand, L.J., Felsher, B.F.. Redeker, A.G. and Marver, H.S. (1970) Proc. N&l. Acad. Sci. USA 67. 1315-1320 Peterson, L.R., Hamernuik, P.. Bird, T.D. and Labbe. R.F. (1976) Cfin. Chem. 22.1835-1840 Magnussen, C.R.. Levi% J.B., Doherty. J.M., Cheesman, J.O. and Tchudy, D.P. (1974) Blood 44, 857-868 Mandel. P., Koehl, C. and Werthenschlag, J. (1974) Ann. Biol. Clin. 32, 353-358 Piepkorn. M.W., Hamemyik, P. and Labbe. R.F. (1978) Clin. Chem. 24/10,1751-1754 Blum, M., Koehl, C. and Abecassis. 3. (1978) Clin. Cbim. Acta 87, 119-125 GrandchamP, B., Phung, N’G., Grelier, M. and Nordmann, Y. (1976) Clin. Chim. Acta 70. 113-118 Andriolo,
244 10 Leber. H.. Sinning, P. and Schutterle. G. (1974) Proc. Eur. Dial. Transplant. ASSOC.11. 383-390 11 Goubeaud. G., Leber. H.W.. Schott. H.H., Schutterle. G. (1976) XIII Congr. Eur. Dial. Transplant Assoc. Hamburg, Germany, June 22-25. pp. 37 12 Leber. H.W.. Neuhauser. M.. Goubeaud, G.. Schutterle, G. (1976) XIII Congr. Eur. Dial. Transplant Assoc. Hamburg, Germany. June, 22-25, PP. 265