Porphyrin-heme pathway: regulation by intermediates in bile acid synthesis.
Dihydroxycoprostane and trihydroxycoprostane, intermediates in normal bile acid synthesis in the liver, enhanced the rate of porphyrin synthesis in cultured liver cells by induction of delta-aminolevulinate synthetase, the rate-limiting enzyme for this pathway. Other 5beta-cholestane derivatives and cholest-5-ene derivatives were ineffective. The selectivity of the induction may indicate that the above-mentioned coprostanes have a physiological role in porphyrin synthesis.
D000624:5-Aminolevulinate Synthetase / Q000378:metabolism*; D000818:Animals; D001647:Bile Acids and Salts / Q000096:biosynthesis / Q000494:pharmacology; D002478:Cells, Cultured; D002642:Chick Embryo; D002776:Cholestanes / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002777:Cholestanols; D002784:Cholesterol / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D006418:Heme / Q000494:pharmacology; D006914:Hydroxysteroids / Q000037:antagonists & inhibitors / Q000494:pharmacology; D008099:Liver / Q000201:enzymology*; D011166:Porphyrins / Q000096:biosynthesis*
D001647:Bile Acids and Salts; D002776:Cholestanes; D002777:Cholestanols; D006914:Hydroxysteroids; D011166:Porphyrins; C007426:dihydroxycoprostane; D006418:Heme; C009561:3,7,12-trihydroxycoprostane; D002784:Cholesterol; D000624:5-Aminolevulinate Synthetase