Physicochemical and physiological properties of 5alpha-cyprinol sulfate, the toxic bile salt of cyprinid fish.
5alpha-Cyprinol sulfate was isolated from bile of the Asiatic carp, Cyprinus carpio. 5alpha-Cyprinol sulfate was surface active and formed micelles; its critical micellization concentration (CMC) in 0.15 M Na+ using the maximum bubble pressure device was 1.5 mM; by dye solubilization, its CMC was approximately 4 mM. At concentrations >1 mM, 5alpha-cyprinol sulfate solubilized monooleylglycerol efficiently (2.1 molecules per mol micellar bile salt). When infused intravenously into the anesthetized rat, 5alpha-cyprinol sulfate was hemolytic, cholestatic, and toxic. In the isolated rat liver, it underwent little biotransformation and was poorly transported (Tmax congruent with 0.5 micromol/min/kg) as compared with taurocholate. 5alpha-Cyprinol, its bile alcohol moiety, was oxidized to its corresponding C27 bile acid and to allocholic acid (the latter was then conjugated with taurine); these metabolites were efficiently transported. 5alpha-Cyprinol sulfate inhibited taurocholate uptake in COS-7 cells transfected with rat asbt, the apical bile salt transporter of the ileal enterocyte. 5alpha-Cyprinol had limited aqueous solubility (0.3 mM) and was poorly absorbed from the perfused rat jejunum or ileum. Sampling of carp intestinal content indicated that 5alpha-cyprinol sulfate was present at micellar concentrations, and that it did not undergo hydrolysis during intestinal transit. These studies indicate that 5alpha-cyprinol sulfate is an excellent digestive detergent and suggest that a micellar phase is present during digestion in cyprinid fish.
Goto
T
T
Division of Gastroenterology, Department of Medicine, University of California, San Diego, CA 92093-0813, USA.
Holzinger
F
F
Hagey
L R
LR
Cerrè
C
C
Ton-Nu
H-T
HT
Schteingart
C D
CD
Steinbach
J H
JH
Shneider
B L
BL
Hofmann
A F
AF
D000818:Animals; D001646:Bile / Q000737:chemistry; D001647:Bile Acids and Salts / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism* / Q000633:toxicity; D001692:Biological Transport; D001711:Biotransformation; D002347:Carps / Q000378:metabolism; D002460:Cell Line; D002777:Cholestanols / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism* / Q000633:toxicity; D066298:In Vitro Techniques; D007413:Intestinal Mucosa / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D015394:Molecular Structure; D010477:Perfusion; D051381:Rats; D021241:Spectrometry, Mass, Electrospray Ionization; D013500:Surface Tension
D001647:Bile Acids and Salts; D002777:Cholestanols; C023378:anhydrocyprinol