1
|
Yao JF, Zhou N, Bai L, Xu PX, Liu KL, Xue M. Simultaneous determination of five novel luteinizing hormone-releasing hormone antagonists by LC-MS and pharmacokinetics in rats following cassette dosing. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 962:94-101. [PMID: 24911546 DOI: 10.1016/j.jchromb.2014.05.035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 05/15/2014] [Accepted: 05/17/2014] [Indexed: 10/25/2022]
Abstract
Long acting luteinizing hormone-releasing hormone (LHRH) antagonists designed to be protease-resistant were a series of novel decapeptides structurally similar to LHRH. In the present work, a high-throughput method based on a LC-MS/MS has been developed for the simultaneous determination of pharmacokinetics of five LHRH antagonists in rat via cassette dosing. The method was performed under selected reaction monitoring (SRM) in positive ion mode. The analytes were extracted from rat plasma by liquid-liquid extraction with acetonitrile. Chromatographic separation of the analytes was successfully achieved on a Hypersil Gold (100mm×2.1mm, 3μm) using a mobile phase composed of acetonitrile-water (30:70) containing 0.05% (v/v) formic acid. The result showed good linearity and selectivity were obtained for all antagonists. The limits of quantification of the five LHRH antagonists were from 5 to 10ng/mL. The average extract recoveries in the rat plasma were all over 72%. The intra-day and inter-day precisions (R.S.D. %) were all within 10% and the accuracy was ranged from 92.54 to 109.05%. This method has been successfully applied to the pharmacokinetic studies of the five LHRH antagonists. The results indicated that the plasma drug concentrations versus time curves after intravenous injection of five antagonists via cassette dosing were all fitted to a two-compartment model. The pharmacokinetic parameters of five LHRH antagonists suggested that LY616 could be the more stable candidate drugs and optimized as the candidate drug for further study. Our studies enabled high-throughput rapid screening for pharmacokinetic assessment of new peptide candidates, and provided abundant information on the metabolic properties of these LHRH antagonists.
Collapse
Affiliation(s)
- Jin-Feng Yao
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing 10069, China; Yanjing Medical College, Capital Medical University, Beijing 101300, China
| | - Ning Zhou
- Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China
| | - Lu Bai
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing 10069, China; Beijing Laboratory for Biomedical Detection Technology and Instrument, Beijing, China
| | - Ping-Xiang Xu
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing 10069, China; Beijing Laboratory for Biomedical Detection Technology and Instrument, Beijing, China
| | - Ke-Liang Liu
- Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China
| | - Ming Xue
- Department of Pharmacology, School of Basic Medical Sciences, Capital Medical University, Beijing 10069, China; Beijing Laboratory for Biomedical Detection Technology and Instrument, Beijing, China.
| |
Collapse
|
2
|
Qian X, Dong H, Hu X, Tian H, Guo L, Shen Q, Gao X, Yao W. Analysis of the interferences in quantitation of a site-specifically PEGylated exendin-4 analog by the Bradford method. Anal Biochem 2014; 465:50-2. [PMID: 24953009 DOI: 10.1016/j.ab.2014.06.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/09/2014] [Accepted: 06/11/2014] [Indexed: 10/25/2022]
Abstract
Protein modification has been found to affect the estimation of protein concentration in some of the traditional dye-based absorbance measurements. In this work, a distinct reduction in A595 was observed during the quantitation of a PEGylated exendin-4 analogue (Ex4C) by the Bradford method and the PEGylation process was found to interfere with the measurement. Lys(12), Arg(20), and Lys(27) were further proved to be the major amino acids that functioned as dye-binding sites. The shielding effect produced by the large polymer was demonstrated to depend on the length of PEG that was used for modification.
Collapse
Affiliation(s)
- Xiaowei Qian
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Hongxia Dong
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Xiaojing Hu
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Hong Tian
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Linfeng Guo
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Qingliang Shen
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China
| | - Xiangdong Gao
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China.
| | - Wenbing Yao
- Department of Biochemistry, China Pharmaceutical University, Nanjing 210009, China.
| |
Collapse
|
3
|
Ho H, Li Y, Nie G. Inhibition of embryo implantation in mice through vaginal administration of a proprotein convertase 6 inhibitor. Reprod Biol 2014; 14:155-9. [PMID: 24856475 DOI: 10.1016/j.repbio.2013.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 12/24/2013] [Indexed: 11/29/2022]
Abstract
Uterine proprotein convertase 6 (PC6) plays a critical role in embryo implantation in both mice and women. It was hypothesized that inhibiting uterine PC6 could prevent pregnancy. Vaginal administration of a PC6 inhibitor presents the ideal route for local drug delivery. A peptide-based PC6 inhibitor, C-30k-PEG Poly R that was previously shown to have properties of increased vaginal absorption and penetration was tested for its contraceptive potential in mice following vaginal administration. The study demonstrated that this approach could inhibit embryo implantation in some mice (24% completely and 47% partially inhibited).
Collapse
Affiliation(s)
- Huiting Ho
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3168, Australia
| | - Ying Li
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia
| | - Guiying Nie
- Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3168, Australia.
| |
Collapse
|
4
|
Ho H, Singh H, Heng S, Nero TL, Paule S, Parker MW, Johnson AT, Jiao GS, Nie G. Small molecule proprotein convertase inhibitors for inhibition of embryo implantation. PLoS One 2013; 8:e81380. [PMID: 24324690 PMCID: PMC3852413 DOI: 10.1371/journal.pone.0081380] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 10/14/2013] [Indexed: 11/19/2022] Open
Abstract
Uterine proprotein convertase (PC) 6 plays a critical role in embryo implantation and is pivotal for pregnancy establishment. Inhibition of PC6 may provide a novel approach for the development of non-hormonal and female-controlled contraceptives. We investigated a class of five synthetic non-peptidic small molecule compounds that were previously reported as potent inhibitors of furin, another PC member. We examined (i) the potency of these compounds in inhibiting PC6 activity in vitro; (ii) their binding modes in the PC6 active site in silico; (iii) their efficacy in inhibiting PC6-dependent cellular processes essential for embryo implantation using human cell-based models. All five compounds showed potent inhibition of PC6 activity in vitro, and in silico docking demonstrated that these inhibitors could adopt a similar binding mode in the PC6 active site. However, when these compounds were tested for their inhibition of decidualization of primary human endometrial stromal cells, a PC6-dependent cellular process critical for embryo implantation, only one (compound 1o) showed potent inhibition. The lack of activity in the cell-based assay may reflect the inability of the compounds to penetrate the cell membrane. Because compound's lipophilicity is linked to cell penetration, a measurement of lipophilicity (logP) was calculated for each compound. Compound 1o is unique as it appears the most lipophilic among the five compounds. Compound 1o also inhibited another crucial PC6-dependent process, the attachment of human trophoblast spheroids to endometrial epithelial cells (a model for human embryo attachment). We thus identified compound 1o as a potent small molecule PC6 inhibitor with pharmaceutical potential to inhibit embryo implantation. Our findings also highlight that human cell-based functional models are vital to complement the biochemical and in silico analyses in the selection of promising drug candidates. Further investigations for compound 1o are warranted in animal models to test its utility as an implantation-inhibiting contraceptive drug.
Collapse
Affiliation(s)
- Huiting Ho
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Harmeet Singh
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
| | - Sophea Heng
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Tracy L. Nero
- Biota Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Sarah Paule
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
| | - Michael W. Parker
- Biota Structural Biology Laboratory and ACRF Rational Drug Discovery Centre, St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Alan T. Johnson
- Department of Chemistry, PanThera Biopharma LLC, Aiea, Hawaii, United States of America
| | - Guan-Sheng Jiao
- Department of Chemistry, PanThera Biopharma LLC, Aiea, Hawaii, United States of America
- * E-mail: (GN); (GSJ)
| | - Guiying Nie
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
- * E-mail: (GN); (GSJ)
| |
Collapse
|