title: Influence of dietary tender cluster beans (Cyamopsis tetragonoloba) on biliary proteins, bile acid synthesis and cholesterol crystal growth in rat bile.
abstract: Tender cluster beans (CBs; Cyamopsis tetragonoloba) are observed to possess anti-lithogenic potential in experimental mice. Formation of cholesterol gallstones in gallbladder is controlled by procrystallizing and anticrystallizing factors present in bile in addition to supersaturation of cholesterol. This study aimed at evaluating the influence of CB on biliary glycoproteins, low molecular weight (LMW) and high molecular weight (HMW) proteins, cholesterol nucleation time, and cholesterol crystal growth in rat hepatic bile. Groups of rats were fed for 10 weeks with 0.5% cholesterol to render the bile lithogenic. Experimental dietary interventions were: 10% freeze-dried CB, 1% garlic powder or their combination. Incorporation of CB into HCD decreased the cholesterol saturation index in bile, increased bile flow and biliary glycoproteins. Dietary CB prolonged cholesterol nucleation time in bile. Electrophoresis of biliary proteins showed the presence of high concentration of 27 kDa protein which might be responsible for the prolongation of cholesterol nucleation time in the CB fed group. Proteins of 20 kDa and 18 kDa were higher in CB treated animals, while the same were less expressed in HCD group. Biliary proteins from CB fed animals reduced cholesterol crystal growth index which was elevated in the presence of proteins from HCD group. Cholesterol-7α-hydroxylase and cholesterol-27-hydroxylase mRNA expression was increased in CB treated animals contributing to the bile acid synthesis. Thus, the beneficial anti-lithogenic effect of dietary CB which primarily is due to reduced cholesterol saturation index was additionally affected through a modulation of the nucleating and anti-nucleating proteins that affect cholesterol crystallization.
authors.affiliation: Department of Biochemistry and Nutrition, CSIR - Central Food Technological Research Institute, Mysore 570 020, India.
authors.forename: Chikkanna K
authors.initials: CK
authors.lastname: Raghavendra
authors.affiliation: Department of Biochemistry and Nutrition, CSIR - Central Food Technological Research Institute, Mysore 570 020, India. Electronic address: ksri.cftri@gmail.com.
authors.forename: Krishnapura
authors.initials: K
authors.lastname: Srinivasan
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001646:Bile / Q000378:metabolism*; D001647:Bile Acids and Salts / Q000096:biosynthesis*; D053493:Cholestanetriol 26-Monooxygenase / Q000096:biosynthesis / Q000235:genetics; D002784:Cholesterol / Q000378:metabolism*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000096:biosynthesis / Q000235:genetics; D003460:Crystallization; D031293:Cyamopsis; D004032:Diet; D042882:Gallstones / Q000517:prevention & control; D005737:Garlic / Q000737:chemistry; D015870:Gene Expression; D006023:Glycoproteins / Q000096:biosynthesis; D008970:Molecular Weight; D028321:Plant Preparations / Q000008:administration & dosage; D017208:Rats, Wistar
chemical_list: D001647:Bile Acids and Salts; D006023:Glycoproteins; D028321:Plant Preparations; D002784:Cholesterol; D002790:Cholesterol 7-alpha-Hydroxylase; D053493:Cholestanetriol 26-Monooxygenase
keywords: Biliary proteins; Cholesterol crystallization; Cholesterol gallstones; Cholesterol nucleation time; Dietary tender cluster beans; Model bile system