title: Metabolism of bis(4-fluorobenzyl)trisulfide and its formation of hemoglobin adduct in rat erythrocytes.
abstract: Bis(4-fluorobenzyl)trisulfide (BFBTS) is a promising new antitumor agent under investigation. It was metabolized rapidly in vivo in rat, but the metabolic fate and primary site of metabolism have not been clarified. In this study, we investigated the role of blood in the metabolism of BFBTS and compared the BFBTS metabolic potencies in whole blood, plasma, and red blood cells (RBCs) in vitro. Three major metabolites of BFBTS [bis(4-fluorobenzyl)disulfide, para-fluorobenzyl-mercaptan, and para-fluorobenzoic acid] were detected in RBCs and whole blood. Significant metabolism of BFBTS was observed in RBCs that were identified as the primary site of BFBTS metabolism. Thiols, including endogenous thiols and hemoglobin, were proven to be the critical factor in BFBTS metabolism. S-Fluorobenzylmercaptocysteine Hb (hemoglobin) adducts were characterized in vitro at BFBTS concentration of 250 μM and higher, whereas such Hb adducts were not detected in RBCs from Sprague-Dawley rats receiving a single intravenous injection of BFBTS at a high dose of 50 mg/kg. Liquid chromatography-tandem mass spectrometry results revealed that adduction induced by BFBTS was prone to take place at Cys125 of globin β chains. Otherwise, glutathionylation of Hb was also observed that may be attributed to the oxidative effect of BFBTS. In summary, BFBTS was unstable when it met with thiols, and RBCs were the main site of BFBTS metabolism. Hb adducts induced by BFBTS could be detected in vitro at high concentration but not in vivo even at high dose.
authors: Department of Pharmaceutical Analysis and Drug Metabolism, Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China.
authors: Hao
authors: H
authors: Pan
authors: Liqiang
authors: L
authors: Gu
authors: Siyuan
authors: S
authors: Sun
authors: Zhongjian
authors: Z
authors: Chen
authors: Hui
authors: H
authors: Zhou
authors: Su
authors: S
authors: Zeng
authors: Huidi
authors: H
authors: Jiang
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D005464:Fluorobenzenes / Q000097:blood / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013440:Sulfides / Q000097:blood / Q000378:metabolism*; D053719:Tandem Mass Spectrometry
chemical_list: D005464:Fluorobenzenes; D006454:Hemoglobins; D013440:Sulfides; C528265:fluorapacin