Muricholic acid
Muricholic acids are a group of bile acids found as one of the main forms in mice, which gives them their name, and at low concentrations in other species.[1] They are detectable at low concentrations in human urine.[2] The three major bile acids in germ-free mice are cholic, α-muricholic and β-muricholic acids.[3] In conventional mice, ω-muricholic acid, and various sulphated forms are also found. Conjugation with taurine or glycine takes place in the liver before secretion.
Muricholic acids differ from the more common bile acids, cholic acid or chenodeoxycholic acid, by having an hydroxyl group at the 6-position. Tauro-muricholic acids were shown to be potent antagonists of the bile acid receptor FXR.[4]
Chemical structures
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α-muricholic acid
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β-muricholic acid
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γ-muricholic acid (hyocholic acid)
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ω-muricholic acid
References
- ↑ Russell DW (2003). "The enzymes, regulation, and genetics of bile acid synthesis". Annu. Rev. Biochem. 72: 137–74. doi:10.1146/annurev.biochem.72.121801.161712. PMID 12543708.
- ↑ Goto, J; Hasegawa, K; Nambara, T; Iida, T (1992). "Studies on steroids. CCLIV. Gas chromatographic-mass spectrometric determination of 4- and 6-hydroxylated bile acids in human urine with negative ion chemical ionization detection". Journal of chromatography 574 (1): 1–7. PMID 1629271.
- ↑ Eyssen HJ, Parmentier GG, Mertens JA (July 1976). "Sulfate bile acids in germ-free and conventional mice". Eur. J. Biochem. 66 (3): 507–14. doi:10.1111/j.1432-1033.1976.tb10576.x. PMID 954753.
- ↑ Sayin SI, Wahlström A, Felin J, et al. (February 2013). "Gut microbiota regulates bile acid metabolism by reducing the levels of tauro-beta-muricholic acid, a naturally occurring FXR antagonist". Cell Metab. 17 (2): 225–35. doi:10.1016/j.cmet.2013.01.003. PMID 23395169.