title: Urinary bile acids as biomarkers for liver diseases I. Stability of the baseline profile in healthy subjects.
abstract: The role of bile acids (BAs) as biomarkers for liver injury has been proposed for decades. However, the large inter- and intra-individual variability of the BA profile has prevented its clinical application. To this end, we investigated the effect of covariates such as food, gender, age, BMI, and moderate alcohol consumption on the BA profile in healthy human subjects. The BA profile was characterized by the calculation of indices that describe the composition, sulfation, and amidation of total and individual BAs. Both inter- and intra-individual variabilities of BA indices were low in serum and even lower in urine compared with those of absolute concentrations of BAs. Serum BA concentrations increased with consumption of food, whereas urinary BA concentrations were mildly affected by food. Gender differences in the urinary and serum BA profile were minimal. The serum and urinary BA profiles were also not affected by age. BMI showed minimal effect on the urine and serum BA profile. Moderate alcohol consumption did not have a significant effect on the BA profile in both urine and serum. When the effect of the type of alcohol was studied, the results indicate that moderate drinking of beer does not affect BA concentrations and has minimal effect on BA indices, whereas moderate wine consumption slightly increases BA concentrations without affecting the BA indices. In summary, urinary BA indices showed lower variability and higher stability than absolute BA concentrations in serum and showed minimal changes to covariate effects suggesting their utility as biomarkers in clinic.
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198 yalnouti@unmc.edu.
authors.forename: Sai Praneeth R
authors.initials: SP
authors.lastname: Bathena
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Rhishikesh
authors.initials: R
authors.lastname: Thakare
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Nagsen
authors.initials: N
authors.lastname: Gautam
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Marco
authors.initials: M
authors.lastname: Olivera
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Jane
authors.initials: J
authors.lastname: Meza
authors.affiliation: *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198 *Department of Pharmaceutical Sciences, College of Pharmacy, Department of Internal Medicine, College of Medicine and Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, Nebraska 68198.
authors.forename: Yazen
authors.initials: Y
authors.lastname: Alnouti
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000428:Alcohol Drinking / Q000652:urine; D000577:Amides / Q000652:urine*; D001647:Bile Acids and Salts / Q000097:blood / Q000737:chemistry / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D003627:Data Interpretation, Statistical; D004355:Drug Stability; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008107:Liver Diseases / Q000097:blood / Q000652:urine*; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013431:Sulfates / Q000652:urine*; D055815:Young Adult
chemical_list: D000577:Amides; D001647:Bile Acids and Salts; D015415:Biomarkers; D013431:Sulfates
keywords: bile acid profile; healthy subjects; serum bile acid; stability; urinary bile acid; variability