Drug-Induced Porphyrin Biosynthesis. X. Potentiation of Propanidid-Induced Elevation of δ-Aminolevulinic Acid Synthetase and Porphyrins in Chick Embryo Liver by the Carboxylesterase Inhibitor Bis-[p-nitrophenyl] Phosphate

1973 ◽  
Vol 51 (9) ◽  
pp. 700-704 ◽  
Author(s):  
Hillel Taub ◽  
G. S. Marks

Propanidid, an ultra short-acting non-barbiturate anesthetic containing an ester group, induces δ-aminolevulinic acid (ALA)-synthetase and porphyrin accumulation in 17-day-old chick embryo liver. The potency and duration of action of propanidid in inducing ALA-synthetase activity and porphyrin accumulation was markedly increased when administered to chick embryos which had been pretreated with bis-[p-nitrophenyl] phosphate, an inhibitor of liver carboxylesterase.

1974 ◽  
Vol 52 (4) ◽  
pp. 891-895 ◽  
Author(s):  
V. Krupa ◽  
J. C. Creighton ◽  
M. Freeman ◽  
G. S. Marks

Allylisopropylacetamide caused a decrease in the level of chick embryo liver cytochrome P-450 1 h after administration, followed by an elevation above control levels at a later time period. Propylisopropylacetamide on the other hand did not produce an early decrease in cytochrome P-450 but produced an elevation of cytochrome P-450 at a later time period. Since propylisopropylacetamide is an inducer of δ-aminolevulinic acid synthetase activity and porphyrin accumulation in chick embryo liver, it was concluded that a loss of cytochrome P-450 is not a prerequisite for ALA-synthetase induction as is thought to be the case in rats.


1973 ◽  
Vol 51 (11) ◽  
pp. 863-868 ◽  
Author(s):  
G. S. Marks ◽  
V. Krupa ◽  
M. W. Roomi

Allylisopropylacetamide (AIA) was found to be considerably more potent than propylisopropylacetamide (PIA) in inducing hepatic δ-aminolevulinic acid (ALA) synthetase activity and hepatic porphyrin accumulation in the 17-day-old chick embryo, chickens, and mice of the CBA/J strain. AIA and PIA were shown to be approximately equipotent in inducing ALA synthetase activity and porphyrin accumulation in chick embryo liver cell culture. It is likely that the unusual responsiveness of chick embryo liver cell culture to PIA is not due to species or developmental differences but to the large amount of PIA available to the cultured liver cells.


1980 ◽  
Vol 58 (8) ◽  
pp. 991-995 ◽  
Author(s):  
S. Zimmer ◽  
H. Taub ◽  
G. S. Marks

Five benzodiazepines, flurazepam, nitrazepam, diazepam, oxazepam, and chlordiazepoxide, have been tested for porphyrin-inducing activity in chick embryo liver cell culture and for δ-aminolevulinic acid (ALA) synthetase inducing activity in the 17-day-old chick embryo. Flurazepam and nitrazepam were found to have considerably lower potency than secobarbital whereas diazepam, oxazepam, and chlordiazepoxide were less potent than phenobarbital in these test systems. The following conclusions were arrived at. (1) A hypnotic dose of flurazepam or nitrazepam would be less likely than a comparable dose of secobarbital to increase ALA synthetase activity in a patient with hereditary hepatic porphyria. (2) A sedative dose of diazepam, oxazepam, or chlordiazepoxide would be less likely than a comparable dose of phenobarbital to increase ALA synthetase activity in a patient with hereditary hepatic porphyria. (3) The benzodiazepines, although apparently less likely to precipitate an attack than barbiturates, should be used with great caution in porphyria patients.


1982 ◽  
Vol 60 (2) ◽  
pp. 212-215 ◽  
Author(s):  
Susan P. C. Cole ◽  
Gerald S. Marks ◽  
Paul R. Oritz de Montellano ◽  
Kent L. Kunze

N-Methylprotoporphyrin has been shown to markedly inhibit ferrochelatase activity in chick embryo liver cell culture without inducing δ-aminoievulinic acid (ALA) synthetase activity. This result supports the idea that the effects of 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine (DDC) on ALA synthetase activity and ferrochelatase activity are dissociated and that inhibition of ferrochelatase alone is not sufficient to cause induction of ALA synthetase. We conclude that the porphyrinogenic activity of DDC can be explained only in part by the actions of N-methylprotoporphyrin.


1977 ◽  
Vol 55 (3) ◽  
pp. 552-559 ◽  
Author(s):  
William J. Racz ◽  
Lynette Hunter ◽  
Richard G. F. Wanless ◽  
Miriam V. McDonald ◽  
Joyce A. Moffat

To elucidate the major metabolic pathways of DDC analogues, the effect of inhibitors of oxidative and hydrolytic microsomal enzymes on the rate of metabolism of these compounds in chick embryo liver cell cultures has been examined. The metabolism of 3,5-diethoxycarbonyl-2,4,6-trimethylpyridine (Ox-DDC) was inhibited threefold by piperonyl butoxide and SKF-525A (β-diethylaminoethyl-diphenyl-n-propylacetate-HCl), but only onefold by bis(p-nitrophenyl)phosphate (BNPP). This indicates that this compound is metabolized predominately by an oxidative route and hydrolysis is a minor pathway. The half-life of 3,5-diethoxycarbonyl-2,6-dimethylpyridine (4-desmethyl-Ox-DDC) was increased 20-fold by BNPP, but no change was observed with piperonyl butoxide, indicating that this compound is metabolized exclusively by hydrolytic mechanisms. Since both piperonyl butoxide and BNPP produced similar changes in the half-life of 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine (DDC), it appears that this compound is metabolized equally via oxidative and hydrolytic mechanisms. In contrast to the intact embryo where Ox-DDC is rapidly metabolized and the effect of the agent on δ-aminolevulinic acid (δ-ALA) synthetase (δ-aminolaevulinate synthetase; EC 2.3.1.37) activity is brief and hence porphyrin accumulation does not occur, in cell culture Ox-DDC is metabolized at a rate sufficiently slow so that induction of δ-ALA synthetase does occur.


1983 ◽  
Vol 61 (6) ◽  
pp. 546-553 ◽  
Author(s):  
G. S. Marks ◽  
S. B. Follows ◽  
D. T. Zelt ◽  
S. P. C. Cole

Four patterns of porphyrin accumulation were observed by high-pressure liquid chromatography when chemicals were added to chick embryo liver cells. These patterns provide a guide to the site of action of the chemicals. Protoporphyrin accumulated in response to 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine (DDC), a result consistent with its ability to inhibit ferrochelatase. Uroporphyrin and heptacarboxylic acid porphyrin accumulated in response to 3,3′,4,4′-tetrachlorobiphenyl, 2,2′,4,4′,6,6′-hexachlorobiphenyl, and 3,5-diethoxycarhonyl-2,4,6-trimethylpyridine, a result suggesting inhibition of uroporphyrinogen decarboxylase. Coproporphyrin was the major porphyrin to accumulate in response to allylisopropylacetamide, aromatic amides, and steroids, a result suggesting inhibition of coproporphyrinogen oxidase. A mixture of uroporphyrin, heptacarboxylic acid porphyrin and coproporphyrin accumulated in response to aromatic di- and mono-esters, aliphatic diesters, and aliphatic amides. The pattern observed after addition of excess δ-aminolevulinic acid (ALA) the endogenous substrate of the pathway to the cells was proto- > copro- > uro-porphyrin. This pattern resembled that produced by DDC but by none of the other chemicals. It was concluded that porphyrin accumulation can not be attributed solely to the induction of ALA-synthetase. It appears that porphyrin-inducing chemicals exert an additional effect on one or other of the enzymes of the heme biosynthetic pathway.


1979 ◽  
Vol 236 (3) ◽  
pp. R180-R183 ◽  
Author(s):  
J. O. Holloszy ◽  
W. W. Winder

There is evidence that delta-aminolevulinic acid (ALA) synthetase is the rate-limiting enzyme in heme biosynthesis. Accumulation of the apoproteins of the mitochondrial cytochromes appears to be regulated by availability of heme. Exercise and thyrotoxicosis bring about increases in the cytochromes, and in other mitochondrial enzymes, in muscle. In this context, we have examined the effects of exercise and of thyroid hormones on ALA synthetase activity in skeletal muscle. Treadmill running and injection of thyroid hormones both resulted in significant increases in muscle ALA synthetase activity. A rise in ALA synthetase activity was evident within 17 h after a bout of vigorous exercise and 14 h after a single injection of thyroid hormones. The increase in ALA synthetase preceded the increase in cytochrome c, which was used as a mitochondrial marker. These results are compatible with the hypothesis that a relationship exists between heme synthesis and mitochondrial growth in which the rate-controlling step is ALA synthetase activity.


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