Inhibitor and Substrate Requirements of Sodium Taurocholate Cotransporting Polypeptide and Its Application to Liver Targeting Item Type dissertation Authors Dong, Zhongqi Publication Date 2014 Abstract Human sodium taurocholate cotransporting polypeptide (NTCP) is the bile acid transporter that is also involved in hepatitis virus infection, drug disposition and prodrug targeting. Identification of NTCP inhibitors and substrates may help to treat he... Keywords bile acid transporter; drug induced liver injury (DILI); liver specific drug delivery; NTCP; pharmacophore; Prodrugs; Chemical and Drug Induced Liver Injury Download date 27/09/2021 05:51:57 Link to Item http://hdl.handle.net/10713/4372 ZHONGQI DONG Room 624, 20 Penn street, Baltimore, MD, 21201, [email protected] EDUCATION University of Maryland, Baltimore, Maryland 2009-2014 Ph.D. in Pharmaceutical Science University of Connecticut, Storrs, Connecticut 2007 -2009 M.S. in Molecular and Cell Biology Shanghai Jiao Tong University, Shanghai, China 2003 -2007 B.S. in Biotechnology B.S. minor in Computer Technology and Application RESEARCH EXPERIENCE University of Maryland, Baltimore, Maryland 2009-2014 Advisor: Dr. James E. Polli Designed and synthesized bile acid-ribavirin conjugates as prodrugs to target human sodium taurocholate cotransporting polypeptide (NTCP) for liver specific drug delivery. In vitro characterized permeability, stability and metabolism of ribavirin prodrugs in mouse and human plasma, s9 fraction and whole blood In vivo characterized pharmacokinetics and tissue distribution of ribavirin prodrugs in mice Identified novel inhibitors and substrates of NTCP with radioactive compounds and LC/MS analysis. Collaboratively to develop the qualitative and quantitative computational models to elucidate inhibitor and substrate requirements of NTCP Investigated potential correlation between NTCP inhibition and drug induced liver injury. University of Connecticut, Storrs, Connecticut 2007-2009 Advisor: Dr. Debra A. Kendall Expressed and purified SecA ATPase in E.coli. Used Substituted-Cysteine Accessibility Method (SCAM) to map the three dimensional boundaries of the signal peptide binding sites on E.coli SecA ATPase. Fudan-SJTU-Nottingham Plant Biotechnology R&D 2006-2007 Center, Shanghai, China Advisor: Dr. Kaijin Zuo Cloned the Voltage-Dependent Anion Channel (VDAC) Family from Brassica rapa. PUBLICATIONS Dong Z, Ekins S, Polli JE. Quantitative NTCP Pharmacophore and Lack of Association between DILI and NTCP Inhibition. Eur J Pharm Sci. 2014 Sep 16;66C:1-9. Dong Z, Ekins S, Polli JE. Structure-activity relationship for FDA approved drugs as inhibitors of the human sodium taurocholate cotransporting polypeptide (NTCP). Mol Pharm. 2013 Mar 4;10(3):1008-19. Li Q, Guo D, Dong Z, Zhang W, Zhang LK, Huang SM, Polli JE, Shu Y. Ondansetron can enhance cisplatin-induced nephrotoxicity via inhibition of multiple toxin and extrusion proteins (MATEs). Toxicol Appl Pharmacol. 2013 Aug 31;273(1):100-109. Li Q, Yang H, Peng X, Guo D, Dong Z, Polli JE, Shu Y. Ischemia/Reperfusion-Inducible Protein Modulates the Function of Organic Cation Transporter 1 and Multidrug and Toxin Extrusion 1. Mol Pharm. 2013 Jul 1;10(7):2578-87. ABSTRACTS Dong Z, Ekins S, Polli JE (2013) Lack of correlation between NTCP inhibition alone and drug induced hepatotoxicity. AAPS Annual Meeting, San Antonio, TX Dong Z, Polli JE (2013) Targeting of ribavirin to NTCP to achieve liver specific drug delivery. AAPS Annual Meeting, San Antonio, TX Dong Z, Ekins S, Polli JE (2013) Possible Role of Human NTCP in Drug-induced Liver Injury. AAPS Workshop on Drug Transporters in ADME: From the Bench to the Bedside, Bethesda, MD Dong Z, Ekins S, Polli JE (2012) Identification of Novel Drug Inhibitors of the Bile Acid Transporters NTCP and ASBT. AAPS Annual Meeting, Chicago, IL Dong Z, Ekins S, Polli JE (2011) Pharmacophore model for Sodium Taurocholate Cotransporting Polypeptide (NTCP) inhibition. AAPS Annual Meeting, Washington, DC SKILLS In vitro transporter inhibition and uptake assay, metabolism assay, cytotoxicity assay LC/MS and HPLC method development for small molecules PK/PD modeling (Phoenix WinNonlin, ADAPT II) Small molecule synthesis and characterization using NMR Site direct mutation, Western blot and protein purification HONOR AND SCHOLARSHIPS President’s certificate of commendation, University of Maryland, 2012 Baltimore, The Rho Chi Honor Society 2011 Excellent Academic Scholarship, Shanghai Jiao Tong University 2004 & 2005 TEACHING EXPERIENCE University of Maryland, Baltimore, Maryland 2009-2010 Teacher Assistant at Compounding Lab, Pharmaceutics University of Connecticut, Storrs, Connecticut 2008 - 2009 Teacher assistant at Anatomy and Physiology Lab EXTRACURRICULAR ACTIVITIES Senator of University Student Government Association, 2010-2012 University of Maryland, Baltimore Committee member of International student organization, 2010-2012 University of Maryland, Baltimore President of Chinese Student and Scholar Association, 2010-2011 University of Maryland, Baltimore Representative of Pharmacy Graduate Student Association, 2010-2011 University of Maryland, Baltimore Senator of Graduate Student Association, University of 2010-2011 Maryland, Baltimore Abstract Title of Dissertation: Inhibitor and substrate requirements of sodium taurocholate cotransporting polypeptide and its application to liver targeting Zhongqi Dong, Doctor of Philosophy, 2014 Disseration Directed by: James Polli, Professor, Department of Pharmaceutical Sciences Human sodium taurocholate cotransporting polypeptide (NTCP) is the bile acid transporter that is also involved in hepatitis virus infection, drug disposition and prodrug targeting. Identification of NTCP inhibitors and substrates may help to treat hepatitis B, reduce NTCP mediate drug interaction and develop prodrugs to achieve liver specific drug delivery. However the understanding of structure-activity relationship of NTCP is very limited. One objective of the work in this dissertation is to fill this gap by exploring the inhibitor and substrate requirements of human NTCP. The other objective is to utilize NTCP to achieve liver targeting of ribavirin in order to reduce its off-target side effects. A common feature pharmacophore, a quantitative pharmacophore and a Bayesian model were developed and validated using FDA approved drugs to elucidate the inhibitor requirements of human NTCP. All these in silico models were able to predict NTCP inhibitors. Twenty seven novel NTCP inhibitors were identified which cover variety of therapeutic classes. The substrate requirements of NTCP were studied using native bile acids and bile acid analogs, suggesting a role of hydroxyl pattern and steric interaction in NTCP binding and translocation. One common feature pharmacophore was developed for NTCP substrates, which was used to search a database of FDA approved drugs. Among the retrieved drugs, irbesartan and losartan were identified as novel NTCP substrates, indicating a potential role of NTCP in drug disposition. In order to reduce ribavirin off-target side effects, ribavirin-L-Val-GCDCA was developed as a prodrug to target NTCP. In vitro uptake and metabolic studies indicated that the prodrug was taken up by NTCP, released ribavirin in the mouse live S9 fraction and reduced ribavirin accumulation in red blood cells (RBC). An in vivo study in mice showed that ribavirin-L-Val-GCDCA provided almost the same ribavirin exposure in the liver as ribavirin administration, but with about 2-fold less exposure of ribavirin in RBC, plasma, and kidney, suggesting that ribavirin-L-Val-GCDCA has the potential to achieve greater liver specific delivery of ribavirin. Overall, the work carried out in this dissertation will aid to identify human NTCP inhibitors and substrates, as well as a prodrug design for liver targeting. Inhibitor and Substrate Requirements of Sodium Taurocholate Cotransporting Polypeptide and Its Application to Liver Targeting By Zhongqi Dong Dissertation submitted to the Faculty of the Graduate School of the University of Maryland, Baltimore in partial fulfillment of the requirements for the degree of Doctor of Philosophy 2014 © Copyright 2014 by Zhongqi Dong All rights Reserved Acknowledgements I owe my great gratitude to all that supported me during my five years study here and I sincerely thank those that helped me to make this dissertation possible. I firstly want to extend my gratitude towards my advisor Dr. James Polli for his fully support and guidance on my dissertation. He is one of the few advisors who give their students the trust and freedom as much as possible which allowed me to try different ideas, gain a lot of hands on experience and help me to overcome many difficult occasions. His enthusiasm and dedication toward his work inspired me with the example of how to be a good scientist. It is very honored of me to work with him. I also want to show my great gratitude towards my current and past committee members. I want to thank Dr. Yan Shu for his advice and guidance on my animal study. I want to thank Dr. Hongbing Wang for his advice on the drug hepatotoxicity assessment. I want to thank Dr. Steven Fletcher for his suggestions on chemistry. I want to thank Dr. Lei Zhang who provided me with helpful suggestions about my whole projects on AAPS annual meeting. I also want to appreciate Dr. Peter Swaan for his help during my qualified exam and teaching me how to be a good PhD candidate. I also want to give my sincere appreciation toward our collaborator