Determination of Bile Acids

The degradation of cholesterol leads to the production of bile acids which are structurally closely related to various steroid hormones. (3-Hydroxysteroid dehydrogenase (EC 1.1.1.51) catalyzes the NAD+-de-pendent oxidation of 3(3-, 17(3- and some l6(3-hydroxysteroids to the respective ketosteroids. The enzyme has been adsorbed on a carbon electrode modified by NMP+TCNQ and the NADH liberated in the reaction oxidized anodically (Albery et al., 1987a). Campanella et al. (1984) employed an enzyme sequence electrode composed of NAD+-de-pendent steroid dehydrogenase and horseradish peroxidase for assay of 7a-hydroxysteroids. 

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Gatti R, Roda A, Cerre C, Bonazzi D, Cavrini V (1997) HPLC-fluorescence determination of bile acids. Biomed Chromatog 11 11-15... 

Kuksis, A., New Developments in Determination of Bile Acids and Steroids... 

B8. Barth, C, A., and Wirthensohn, K., Enzymatic determination of bile acids from liver cells with 3a-hydroxysteroid dehydrogenase—a warning. J. Lipid Res. 22, 1025-1027 (1981). 

D9. Duane, W. C., Adler, R. D., Bennion, L. J., and Ginsberg, R. L., Determination of bile acid pool size in man A simplified method with advantages of increased precision, shortened analysis time, and decreased isotope exposure. J. Lipid Res. 16, 155-158... 

El. Eneroth, F., Hellstrfim, K., and Sjovall, J., A method for quantitative determination of bile acids in human feces. Acta Chem. Scand. 22, 1729-1744 (1968). 

G12. Goto, J., Hasegawa, M., Kato, H., and Nambara, T., A new method for simultaneous determination of bile acids in human bile without hydrolysis. Clin. Chim. Acta 87,141-... 

Klaassen, K., Cas-liquid-chromatographic determination of bile acids in bile. Clin. Chim. Acta 35, 225-229 (1971). 

S33. SjOvall, J., Separation and determination of bile acids. Methods Biochem. Anal. 12, 97-141 (1964). 

V2. Van den Berg, J. W., Van Blankenstein, M., Bosman-Jacobs, E. P., Frenkel, M., Hoerchner, P., Oost-Harwig, O. I., and Wilson, J. P., Solid phase radioimmunoassay for determination of conjugated cholic acid in serum. Clin. Chim. Acta 73, 3TI-W3 (1976). Van den Ende, A., Radecker, C. E., Mairuhu, W. M., and Van Zanten, A. P., Improved extraction procedure for determination of bile acids in foeces. Clin. Chim. Acta 121, 95-109 (1982). 

K13. Kuksis, A., Newer developments in determination of bile acids and steroids by gas chromatography. Methods Biochem. Anal. 14, 325-454 (1966). 

Perwaiz, S., B. Tuchweber, D. Mignault, T. GUat, and I. M. Yousef. 2001. Determination of bile acids in biological fluids by liquid chromatography-electrospray tandem mass spectrometry. Journal of Lipid Research 42 114—119. 

The methods available for the quantitation of bile acid metabolism in man have been reviewed recently by Hofmann et al. (53). The measurement can be performed by the following methods (a) fecal determination of bile acids, (b) fecal excretion of administered labeled bile acids, (c) isotope dilution, and (d) measurement of bile salt pool. 

There is no direct evidence so far that the actual concentration of serum cholesterol would determine bile acid production and elimination in man. For instance, increase of serum cholesterol by dietary cholesterol is not associated with compensatory increase in bile acid production (63,71,86,87). This does not exclude the possibility that an increase of some lipoprotein subfraction would stimulate bile acid synthesis. Thus determinations of bile acid synthesis by the isotope dilution method have shown markedly high values in triglyceridemic subjects (69), though according to sterol balance data this association is mostly determined by the degree of obesity of these patients (11,63). It is also interesting to note that though the serum cholesterol level and bile acid production are not normally correlated with each other, bile acid synthesis and the serum cholesterol pool are closely correlated in normocholesterolemic nonobese and obese subjects and in hypercholesterolemic individuals (88). 

It seems to be a general observation that the proportion of chenodeoxy-cholic acid is increased in liver cirrhosis. Thus the ratio cholic acid/cheno-deoxycholic acid has been found to be decreased in the bile (23), serum (52,134,193,195-198), and urine (88,199) of cirrhotic subjects. Since the ratios of cholic acid, chenodeoxycholic acid, and deoxycholic acid appear to be approximately the same in bile and serum (200,201), and perhaps also in urine, it seems quite obvious that the bile acid pattern in any of these three sources is similar to that produced by the liver. Simultaneous determinations of bile acids from bile, serum, and urine have not been made, however. The relative increase of chenodeoxycholic acid has been interpreted to indicate a hindrance of 12a-hydroxylation in liver injury when the formation of cholic acid is decreased in favor of chenodeoxycholic acid (202). This, on the other hand, changes the pattern of secondary bile acids so that relatively more lithocholic acid is formed in the colon (191,200,202), the amount of deoxycholic acid being reduced (23,52,134,193,195-198), particularly because quantitatively only a small portion of the bile acids escapes daily from the ileum to the colon (23). 

The first step should preferably lead to a group separation of bile acids and to elimination of non-bile acid contaminants. In quantitative work it may be useful to add—at this stage or earlier—labeled compounds, which permit an estimation of recovery of bile acids of different polarities. Tauro-cholic and 3-ketocholanoic acids constitute suitable extremes in polarity. If specific bile acids are to be analyzed, one may add a suitable internal standard to the biological material. Thus, Rooversc/ r/. (36) used nordeoxy-cholic acid for gas chromatographic determination of bile acids in feces and plasma. 

Determination of Bile Acids in Needle Biopsies of Human Liver Biochem. Med. 8(2) 280-286 (1973) CA 80 24422s... 

On the Determination of Bile Acids in Serum and Bile Using Gas-Liquid Chromatography Clin. Chim. Acta 75(l) 41-47 (1977) CA 86 135745t... 

Karlaginis, G., and Paumgartner, G. Determination of Bile Acids in Serum... 

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