title: A phylogenetic survey of biliary lipids in vertebrates.
abstract: Biliary lipids (bile salts, phospholipids, cholesterol, plant sterols) were determined in 89 vertebrate species (cartilaginous and bony fish, reptiles, birds, and mammals), and individual phospholipid classes were measured in 35 species. All samples contained conjugated bile salts (C(27) bile alcohol sulfates and/or N-acyl amidates of C(27) and/or C(24) bile acids). Phospholipids were generally absent in the bile of cartilaginous fish and reptiles and were present in low amounts relative to bile salts in bony fish and most birds. In mammals, the phospholipid-bile salt ratio varied widely. The bile from species with low biliary phospholipid-bile salt ratios often contained a high proportion of sphingomyelin, confirmed by HPLC-MS. In species with a high phospholipid-bile salt ratio, the predominant biliary phospholipid was phosphatidylcholine (PC). The phospholipid-bile salt ratio correlated weakly with the calculated weighted hydrophobic index value. Cholesterol was present in the bile of virtually all species, with plant sterols uniformly being present in only trace amounts. The cholesterol-bile salt ratio tended to be higher in mammals than in non-mammals, but bile of all species was unsaturated. Thus, most nonmammalian vertebrates have relatively low levels of biliary phospholipid and cholesterol, suggesting that cholesterol is eliminated predominantly as bile salts. Mammals have a higher phospholipid and cholesterol to bile salt ratio, with the dominant phospholipid being PC.
authors.affiliation: Department of Gastroenterology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Antonio
authors.initials: A
authors.lastname: Moschetta
authors.forename: Fang
authors.initials: F
authors.lastname: Xu
authors.forename: Lee R
authors.initials: LR
authors.lastname: Hagey
authors.forename: Gerard P
authors.initials: GP
authors.lastname: van Berge-Henegouwen
authors.forename: Karel J
authors.initials: KJ
authors.lastname: van Erpecum
authors.forename: Jos F
authors.initials: JF
authors.lastname: Brouwers
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Cohen
authors.forename: Molly
authors.initials: M
authors.lastname: Bierman
authors.forename: Helen H
authors.initials: HH
authors.lastname: Hobbs
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Steinbach
authors.forename: Alan F
authors.initials: AF
authors.lastname: Hofmann
mesh_terms: D000818:Animals; D001646:Bile / Q000737:chemistry*; D001647:Bile Acids and Salts / Q000235:genetics*; D001717:Birds; D002777:Cholestanols / Q000378:metabolism; D002784:Cholesterol / Q000235:genetics*; D006801:Humans; D008322:Mammals; D009530:Nicergoline; D010743:Phospholipids / Q000235:genetics*; D010802:Phylogeny; D012104:Reptiles; D014714:Vertebrates / Q000235:genetics*
chemical_list: D001647:Bile Acids and Salts; D002777:Cholestanols; D010743:Phospholipids; D002784:Cholesterol; D009530:Nicergoline