title: Differential diagnosis of gallstones by using hypericin as a fluorescent optical imaging agent.
abstract: OBJECTIVE
  To explore the feasibility of using hypericin as an optical imaging probe with affinity for cholesterol for differential fluorescent detection of human gallstones.
  
  
  METHODS
  Cholesterol, mixed and pigment stones from cholecystectomy patients were incubated with hypericin or solvent. After 72 h, the stones were analysed for fluorescence (365 nm) and treated with 2-propanol/dimethyl sulfoxide for high performance liquid chromatography (HPLC) analysis. Rats with virtual gallbladder containing human cholesterol, mixed or pigment gallstones (VGHG) received 5 mg/kg hypericin or solvent and VGHG rats with cholesterol stones were given different hypericin doses (5-15 mg/kg). Twelve hours later, the stones were analysed at 365 nm. Biliary excretion and metabolites of hypericin were assessed in common bile duct (CBD) cannulated rats for 9 h using fluorospectrometry, HPLC and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS).
  
  
  RESULTS
  Homogeneous high fluorescence was seen on cholesterol stones either pre-incubated with hypericin or extracted from VGHG rats receiving hypericin. Mixed stones showed a dotted fluorescent pattern, whereas pigment and solvent-treated ones lacked fluorescence. HPLC showed 7.68, 6.65 and 0.08 × 10(-3) M of cholesterol in extracts from cholesterol, mixed, and pigment gallstones, respectively. Hypericin accounted for 2.0, 0.5 and 0.2 × 10(-6) M in that order. On cholesterol stones from VGHG rats receiving different hypericin doses, a positive correlation was observed between dose and fluorescence. In the bile from CBD-cannulated rats, fluorescence represented 20% of the injected dose with two peaks in 9 h. HPLC analysis revealed that hypericin conjugates reached 60% of the peak area. By MALDI-TOF MS, hypericin-glucuronide was detected.
  
  
  CONCLUSIONS
  This study proves the potential use of hypericin for differential fluorescent detection of human gallstones regarding their chemical composition.
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Marlein
authors.initials: M
authors.lastname: Miranda Cona
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Ye-Wei
authors.initials: YW
authors.lastname: Liu
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Antoine
authors.initials: A
authors.lastname: Hubert
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Ting
authors.initials: T
authors.lastname: Yin
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Yuan-Bo
authors.initials: YB
authors.lastname: Feng
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: de Witte
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Etienne
authors.initials: E
authors.lastname: Waelkens
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Yan-Sheng
authors.initials: YS
authors.lastname: Jiang
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Stefaan
authors.initials: S
authors.lastname: Mulier
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xia
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Gang
authors.initials: G
authors.lastname: Huang
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Raymond
authors.initials: R
authors.lastname: Oyen
authors.affiliation: Marlein Miranda Cona, Ye-Wei Liu, Ting Yin, Yuan-Bo Feng, Yan-Sheng Jiang, Stefaan Mulier, Raymond Oyen, Yi-Cheng Ni, Department of Imaging and Pathology, Faculty of Medicine, Biomedical Sciences Group, University Hospitals, KU Leuven, B-3000 Leuven, Belgium.
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Ni
mesh_terms: D000818:Animals; D000873:Anthracenes; D002784:Cholesterol / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003937:Diagnosis, Differential; D005453:Fluorescence; D042882:Gallstones / Q000175:diagnosis*; D006801:Humans; D008297:Male; D061848:Optical Imaging; D010569:Perylene / Q000031:analogs & derivatives* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000873:Anthracenes; D010569:Perylene; C004965:hypericin; D002784:Cholesterol
keywords: Differential detection; Fluorescence; Human gallstones; Hypericin; Rat model of cholelithiasis