1
|
Sekar V, Vedhachalam D, Vb A, Sivaraman S, Janakarajan V, Sethuraman S, Shiroor SG, Geoffroy JMM. Combating Alcohol Adduct Impurity in Immunosuppressant Drug Product Manufacturing: A Scientific Investigation for Enhanced Process Control. Pharm Res 2024; 41:983-1006. [PMID: 38561580 DOI: 10.1007/s11095-024-03695-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Accepted: 03/21/2024] [Indexed: 04/04/2024]
Abstract
OBJECTIVE This research aims to elucidate critical impurities in process validation batches of tacrolimus injection formulations, focusing on identification and characterization of previously unreported impurity at RRT 0.42, identified as the tacrolimus alcohol adduct. The potential root causes for the formation of new impurity was determined using structured risk assessment by cause and effect fishbone diagram. The primary objective was to propose mitigation plan and demonstrate the control of impurities with 6 month accelerated stability results in development batches. METHODS The investigation utilizes method validation and characterization studies to affirm the accuracy of quantifying the tacrolimus alcohol adduct. The research methodology employed different characterization techniques like rotational rheometer, ICP‒MS, MALDI-MS, 1H NMR, 13C NMR, and DEPT-135 NMR for structural elucidation. Additionally, the exact mass of the impurity is validated using electrospray ionization mass spectra. RESULTS Results indicate successful identification and characterization of the tacrolimus alcohol adduct. The study further explores the transformation of Tacrolimus monohydrate under various conditions, unveiling the formation of Tacrolimus hydroxy acid and proposing the existence of a novel degradation product, the Tacrolimus alcohol adduct. Six-month data from development lots utilizing Manufacturing Process II demonstrate significantly lower levels of alcohol adducts. CONCLUSIONS Manufacturing Process II, selectively locates Tacrolimus within the micellar core of HCO-60, this prevent direct contact of ethanol with Tacrolimus which minimizes impurity alcohol adduct formation. This research contributes to the understanding of tacrolimus formulations, offering ways to safeguard product integrity and stability during manufacturing and storage.
Collapse
Affiliation(s)
- Vasanthakumar Sekar
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113.
| | - Devarajan Vedhachalam
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113
| | - ArunKumar Vb
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113
| | - Sivananthan Sivaraman
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113
| | - Venkatakrishnan Janakarajan
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113
| | - Sai Sethuraman
- Pfizer Healthcare India Private Limited, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 8th Floor, Block C, IIT Madras Research Park, Kanagam Road, Taramani, Chennai, India, 600113
| | - Sandeep G Shiroor
- Pfizer, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 375 North Field Drive, Lake Forest, Illinois, 60045, USA
| | - Jean-Marie M Geoffroy
- Pfizer, Medicinal Sciences-Pharmaceutical Sciences Small Molecules, Pfizer Research & Development, 375 North Field Drive, Lake Forest, Illinois, 60045, USA
| |
Collapse
|
2
|
de Loor H, Vanhove T, Annaert P, Lescrinier E, Kuypers D. Determination of tacrolimus, three mono-demethylated metabolites and a M1 tautomer in human whole blood by liquid chromatography - tandem mass spectrometry. J Pharm Biomed Anal 2021; 205:114296. [PMID: 34392130 DOI: 10.1016/j.jpba.2021.114296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/20/2021] [Accepted: 07/30/2021] [Indexed: 12/22/2022]
Abstract
The immunosuppressant tacrolimus is the primary drug used in kidney transplantation to prevent organ rejection. A sensitive ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed to measure tacrolimus and its three known mono-demethylated metabolites 13-O-desmethyl tacrolimus (M1), 31-O-desmethyl tacrolimus (M2), 15-O-desmethyl tacrolimus (M3). By generating the metabolites to use as standards after incubation of tacrolimus with rat liver microsomes, we discovered multiple M1 peaks which we identified as two tautomers of M1. The M1 tautomer II was also successfully validated in this method. The separation and purification of the metabolites and tautomers were performed by semi-preparative liquid chromatography with UV-detection, while confirmation was done by UPLC-MS/MS and Nuclear Magnetic Resonance. For quantification an easy sample preparation was performed with zinc sulfate and acetonitrile as cell lyses and precipitation. Detection was performed in positive electrospray ionization. By better characterization of the metabolites and the tautomers, we could possibly explain insight into the clinical condition and thus adjust the immunosuppressant therapy individually per patient. Calibration curves were linear for all compounds. Precision was assessed according to the NCCLS EP5-T guideline, being below 15 % and mean recoveries were between 93 and 110 % for tacrolimus, its three metabolites and the M1 tautomer II. The validated method was successfully applied in a cohort of 20 patients after kidney transplantation.
Collapse
Affiliation(s)
- Henriette de Loor
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Nephrology and Renal Transplantation Research Group, B-3000, Leuven, Belgium
| | - Thomas Vanhove
- KU Leuven - University of Leuven, Department of Microbiology and Immunology, Nephrology and Renal Transplantation Research Group, B-3000, Leuven, Belgium; University Hospitals Leuven, Department of Nephrology and Renal Transplantation, B-3000, Leuven, Belgium
| | - Pieter Annaert
- KU Leuven - University of Leuven, Department of Pharmaceutical and Pharmacological Sciences, Drug Delivery and Disposition, B-3000, Leuven, Belgium
| | - Eveline Lescrinier
- KU Leuven - University of Leuven, Department of Pharmaceutical and Pharmacological Sciences, Medicinal Chemistry, B-3000, Leuven, Belgium
| | - Dirk Kuypers
- University Hospitals Leuven, Department of Nephrology and Renal Transplantation, B-3000, Leuven, Belgium.
| |
Collapse
|
3
|
Prajapati M, Eiriksson FF, Loftsson T. Stability characterization, kinetics and mechanism of tacrolimus degradation in cyclodextrin solutions. Int J Pharm 2020; 586:119579. [PMID: 32599134 DOI: 10.1016/j.ijpharm.2020.119579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/21/2020] [Accepted: 06/22/2020] [Indexed: 11/27/2022]
Abstract
Tacrolimus is a macrolide lactone and potent immunosuppressant. It is highly lipophilic and has very limited aqueous solubility. Tacrolimus is highly susceptible to hydrolysis which results in very limited stability in aqueous solutions. Besides this, tacrolimus also undergoes dehydration and epimerization. Cyclodextrin (CD) complexation can increase the solubility and stability of hydrophobic drugs in aqueous solutions through the formation of drug/CD complexes. The aim of this study was to investigate degradation kinetics, mechanism and stability of tacrolimus in aqueous CD solutions, with the ultimate goal of developing an aqueous vehicle for ophthalmic delivery. For this, phase-solubility and kinetic studies in aqueous solutions containing different CDs at different pH values were performed. Mass spectrometry studies were also performed to elucidate the degradation mechanism of the drug in aqueous CD solution. The study showed that the drug has maximum stability between pH 4 and 6 and hydrolysis was the main cause of tacrolimus degradation in aqueous 2-hydroxypropyl-βCD (HPβCD) solutions. βCD and its derivatives were the better CD solubilizers for tacrolimus. The solubility and stability studies were further conducted with CD and surfactants, which is tyloxapol, tween 80 and poloxamer 407, where the combination provided better results compared to individual components.
Collapse
Affiliation(s)
- Manisha Prajapati
- Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, 107 Reykjavik, Iceland.
| | | | - Thorsteinn Loftsson
- Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, 107 Reykjavik, Iceland.
| |
Collapse
|
4
|
Forced degradation of tacrolimus and the development of a UHPLC method for impurities determination. ACTA PHARMACEUTICA (ZAGREB, CROATIA) 2019; 69:363-380. [PMID: 31259735 DOI: 10.2478/acph-2019-0025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/29/2018] [Indexed: 01/19/2023]
Abstract
An ultra-high performance liquid chromatography method for simultaneous determination of tacrolimus impurities in pharmaceutical dosage forms has been developed. Appropriate chromatographic separation was achieved on a BEH C18 column using gradient elution with a total run time of 14 min. The method was applied to analyses of commercial samples and was validated in terms of linearity, precision, accuracy, sensitivity and specificity. It was found to be linear, precise and accurate in the range of 0.05 to 0.6 % of the impurities level in pharmaceutical dosage forms. Stability indicating power of the method was demonstrated by the results of forced degradation studies. The forced degradation study in solution revealed tacrolimus instability under stress alkaline, thermal, light and photolytic conditions and in the presence of a radical initiator or metal ions. The drug was stable at pH 3-5. Solid-state degradation studies conducted on amorphous tacrolimus demonstrated its sensitivity to light, elevated temperature, humidity and oxidation.
Collapse
|
5
|
Guo Y, Crnkovic CM, Won KJ, Yang X, Lee JR, Orjala J, Lee H, Jeong H. Commensal Gut Bacteria Convert the Immunosuppressant Tacrolimus to Less Potent Metabolites. Drug Metab Dispos 2018; 47:194-202. [PMID: 30598508 DOI: 10.1124/dmd.118.084772] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 12/27/2018] [Indexed: 12/27/2022] Open
Abstract
Tacrolimus exhibits low and variable drug exposure after oral dosing, but the contributing factors remain unclear. Based on our recent report showing a positive correlation between fecal abundance of Faecalibacterium prausnitzii and oral tacrolimus dose in kidney transplant patients, we tested whether F. prausnitzii and other gut abundant bacteria are capable of metabolizing tacrolimus. Incubation of F. prausnitzii with tacrolimus led to production of two compounds (the major one named M1), which was not observed upon tacrolimus incubation with hepatic microsomes. Isolation, purification, and structure elucidation using mass spectrometry and nuclear magnetic resonance spectroscopy indicated that M1 is a C-9 keto-reduction product of tacrolimus. Pharmacological activity testing using human peripheral blood mononuclear cells demonstrated that M1 is 15-fold less potent than tacrolimus as an immunosuppressant. Screening of 22 gut bacteria species revealed that most Clostridiales bacteria are extensive tacrolimus metabolizers. Tacrolimus conversion to M1 was verified in fresh stool samples from two healthy adults. M1 was also detected in the stool samples from kidney transplant recipients who had been taking tacrolimus orally. Together, this study presents gut bacteria metabolism as a previously unrecognized elimination route of tacrolimus, potentially contributing to the low and variable tacrolimus exposure after oral dosing.
Collapse
Affiliation(s)
- Yukuang Guo
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Camila Manoel Crnkovic
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Kyoung-Jae Won
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Xiaotong Yang
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - John Richard Lee
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Jimmy Orjala
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Hyunwoo Lee
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| | - Hyunyoung Jeong
- Departments of Medicinal Chemistry and Pharmacognosy (Y.G., C.M.C., J.O., H.L.), Pharmacy Practice (K.-J.W., H.J.), Biopharmaceutical Sciences (X.Y., H.J.), and Center for Biomolecular Sciences (Y.G., J.O., H.L., H.J.), University of Illinois at Chicago, Chicago, Illinois; and Division of Nephrology and Hypertension, Department of Medicine, Weill Cornell Medicine, New York, New York (J.R.L.)
| |
Collapse
|
6
|
Rozman Peterka T, Grahek R, Hren J, Bastarda A, Bergles J, Urleb U. Solid state compatibility study and characterization of a novel degradation product of tacrolimus in formulation. J Pharm Biomed Anal 2015; 110:67-75. [PMID: 25804434 DOI: 10.1016/j.jpba.2015.02.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Revised: 02/21/2015] [Accepted: 02/23/2015] [Indexed: 11/16/2022]
Abstract
Tacrolimus is macrolide drug that is widely used as a potent immunosuppressant. In the present work compatibility testing was conducted on physical mixtures of tacrolimus with excipients and on compatibility mixtures prepared by the simulation of manufacturing process used for the final drug product preparation. Increase in one major degradation product was detected in the presence of magnesium stearate based upon UHPLC analysis. The degradation product was isolated by preparative HPLC and its structure was elucidated by NMR and MS studies. Mechanism of the formation of this degradation product is proposed based on complementary degradation studies in a solution and structural elucidation data. The structure was proven to be alpha-hydroxy acid which is formed from the parent tacrolimus molecule through a benzilic acid type rearrangement reaction in the presence of divalent metallic cations. Degradation is facilitated at higher pH values.
Collapse
Affiliation(s)
| | - Rok Grahek
- Lek Pharmaceuticals d.d., Verovškova 57, SI-1526 Ljubljana, Slovenia
| | - Jure Hren
- Lek Pharmaceuticals d.d., Verovškova 57, SI-1526 Ljubljana, Slovenia
| | - Andrej Bastarda
- Lek Pharmaceuticals d.d., Verovškova 57, SI-1526 Ljubljana, Slovenia
| | - Jure Bergles
- Lek Pharmaceuticals d.d., Verovškova 57, SI-1526 Ljubljana, Slovenia
| | - Uroš Urleb
- Lek Pharmaceuticals d.d., Verovškova 57, SI-1526 Ljubljana, Slovenia
| |
Collapse
|
7
|
Sommers CD, Pang ES, Ghasriani H, Berendt RT, Vilker VL, Keire DA, Boyne MT. Analyses of marketplace tacrolimus drug product quality: Bioactivity, NMR and LC–MS. J Pharm Biomed Anal 2013; 85:108-17. [DOI: 10.1016/j.jpba.2013.07.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 06/25/2013] [Accepted: 07/01/2013] [Indexed: 02/01/2023]
|
8
|
Some transformations of tacrolimus, an immunosuppressive drug. Eur J Pharm Sci 2012; 48:514-22. [PMID: 23238171 DOI: 10.1016/j.ejps.2012.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/15/2012] [Accepted: 12/02/2012] [Indexed: 11/20/2022]
Abstract
Transformations of the macrocyclic lactone tacrolimus (1), an important immunosuppressive drug produced by Streptomyces species, are described. These transformation products are primarily of interest as reference substances for drug impurity analyses. Upon action of acid (p-toluenesulfonic acid in toluene), tacrolimus is dehydrated by loss of water from the β-hydroxyketone moiety with partial inversion of configuration at C-8, resulting in formation of 5-deoxy-Δ(5,6)-tacrolimus and 5-deoxy-Δ(5,6)-8-epitacrolimus. The structure of the latter was determined by single-crystal X-ray crystallography. The same products are formed upon action of free radicals (iodine in boiling toluene), along with formation of 8-epitacrolimus. The latter is converted by p-toluenesulfonic acid to 5-deoxy-Δ(5,6)-8-epitacrolimus. Treatment of tacrolimus with weak base (1,5-diazabicyclo[4.3.0]nonene) gives, in addition to 8-epitacrolimus, the open-chain acid corresponding to 5-deoxy-Δ(5,6)-tacrolimus, a rare non-cyclic derivative of tacrolimus. Strong base (t-butoxide) causes pronounced degradation of the molecule. Thermolysis of tacrolimus leads to ring expansion by an apparent [3,3]-sigmatropic rearrangement of the allylic ester moiety with subsequent loss of water from the β-hydroxyketone moiety. ¹H and ¹³C NMR spectra of the obtained compounds, complicated by the presence of amide bond rotamers and ketal moiety tautomers, were assigned by extensive use of 2D NMR techniques.
Collapse
|
9
|
Turło J, Gajzlerska W, Klimaszewska M, Król M, Dawidowski M, Gutkowska B. Enhancement of tacrolimus productivity in Streptomyces tsukubaensis by the use of novel precursors for biosynthesis. Enzyme Microb Technol 2012; 51:388-95. [PMID: 23040396 DOI: 10.1016/j.enzmictec.2012.08.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 08/18/2012] [Accepted: 08/21/2012] [Indexed: 11/16/2022]
Abstract
In this report the optimization of biosynthesis of tacrolimus, the immunosupressant widely used in transplantology and dermatology was described. The enhancement of the productivity of Streptomyces tsukubaensis strain was achieved by development of new precursors of tacrolimus biosynthesis, which should allow to reduce the costs of the process. The enrichment of the fermentation medium in pyridine-2-carboxylic acid (picolinic acid), piperidine-2-carboxylic acid (pipecolic acid), pyridine-3-carboxylic acid (nicotinic acid) or pyridine-3-carboxylic acid amide (nicotinamide) caused significant growth of the productivity of tacrolimus: 7-fold, 6-fold, 3-fold and 5-fold, respectively. The optimum concentration of the precursors in medium was 0.0025-0.005%. The investigation of the kinetics of tacrolimus biosynthesis together with the analysis of the impact of tested compounds on the culture growth and NAD (nicotinamide adenine dinucleotide) concentration in S. tsukubaensis cells enables to put forward a hypothesis concerning the mechanism of action of tested culture medium additives. The compounds active as tacrolimus precursors (pipecolic and picolinic acids) are more effective than these active mainly as the growth promoters (nicotinamide and nicotinic acid). Nicotinamide and nicotinic acid--vitamin B₃ components--promote S. tsukubaensis growth most probably due to the stimulation of NAD/NADP biosynthesis.
Collapse
Affiliation(s)
- Jadwiga Turło
- Department of Drug Technology and Pharmaceutical Biotechnology, Medical University of Warsaw, 1 Banacha St, 02-097 Warsaw, Poland.
| | | | | | | | | | | |
Collapse
|
10
|
Ferraboschi P, Colombo D, De Mieri M, Grisenti P. Evaluation, synthesis and characterization of tacrolimus impurities. J Antibiot (Tokyo) 2012; 65:349-54. [DOI: 10.1038/ja.2012.28] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
11
|
Bulusu MARC, Baumann K, Stuetz A. Chemistry of the immunomodulatory macrolide ascomycin and related analogues. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2011; 94:59-126. [PMID: 21833838 DOI: 10.1007/978-3-7091-0748-5_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
12
|
|
13
|
Pappas L, Kiss A, Levitt J. Compatibility of tacrolimus ointment with corticosteroid ointments of varying potencies. J Cutan Med Surg 2009; 13:140-5. [PMID: 19426622 DOI: 10.2310/7750.2008.08013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Tacrolimus is often coadministered with various topical corticosteroids in the treatment of steroid-responsive dermatoses; however, the stability of these products in combination has not been examined extensively. OBJECTIVE To assess the in vitro compatibility of three tacrolimus-corticosteroid ointment combinations compared with unmixed controls. METHODS Tacrolimus-clobetasol propionate, tacrolimus-desoximetasone, and tacrolimus-hydrocortisone-17-valerate ointment combinations were prepared, stored with unmixed ointments at three temperature/humidity conditions, and evaluated for stability at days 0, 1, 2, 7, 14, and 28 via reverse-phase high-performance liquid chromatography. RESULTS There was no significant difference in the rate of drug degradation in mixed and unmixed ointments over time or across temperatures for tacrolimus (time p = .94; temperature p = .44), clobetasol (time p = .98, temperature p = .30), desoximetasone (time p = .98; temperature p = .94), or hydrocortisone-17-valerate (time p = .87, temperature p = .36). LIMITATIONS This study did not examine the compatibility of tacrolimus with nonointment formulations. CONCLUSION Tacrolimus-clobetasol propionate (superpotent), tacrolimus-desoximetasone (high potent), and tacrolimus-hydrocortisone-17-valerate (midpotent) ointment combinations are chemically compatible for at least 4 weeks.
Collapse
Affiliation(s)
- Lisa Pappas
- Wayne State School of Medicine, Detroit, MI, USA
| | | | | |
Collapse
|
14
|
Wen Y, Wang J, Chen X, Le Z, Chen Y, Zheng W. Application of silver ion in the separation of macrolide antibiotic components by high-speed counter-current chromatography. J Chromatogr A 2009; 1216:4668-72. [DOI: 10.1016/j.chroma.2009.03.082] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 03/24/2009] [Accepted: 03/30/2009] [Indexed: 10/20/2022]
|
15
|
Brath U, Akke M. Differential responses of the backbone and side-chain conformational dynamics in FKBP12 upon binding the transition-state analog FK506: implications for transition-state stabilization and target protein recognition. J Mol Biol 2009; 387:233-44. [PMID: 19361439 DOI: 10.1016/j.jmb.2009.01.047] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2008] [Revised: 01/12/2009] [Accepted: 01/23/2009] [Indexed: 10/21/2022]
Abstract
FKBP12 serves a dual role as a peptidyl-prolyl cis-trans isomerase and as a modulator of several cell signaling pathways. The macrolide FK506 is a transition-state analog of the catalyzed reaction and displaces FKBP12 from its natural target proteins. We compared the conformational exchange dynamics of the backbone and methyl-bearing side chains of FKBP12 in the free and FK506-bound states using NMR relaxation-dispersion experiments. Our results show that the free enzyme exchanges between the ground state and an excited state that resembles the ligand-bound state or Michaelis complex. In FK506-bound FKBP12, the backbone is confined to a single conformation, while conformational exchange prevails for many methyl groups. The residual side-chain dynamics in the transition-state analog-bound state suggests that the transition-state ensemble involves multiple conformations, a finding that challenges the long-standing concept of conformational restriction in the transition-state complex. Furthermore, exchange between alternative conformations is observed in the bound state for an extended network of methyl groups that includes locations remote from the active site. Several of these locations are known to be important for interactions with cellular target proteins, including calcineurin and the ryanodine receptor, suggesting that the conformational heterogeneity might play a role in the promiscuous binding of FKBP12 to different targets.
Collapse
Affiliation(s)
- Ulrika Brath
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Lund University, Lund, Sweden
| | | |
Collapse
|
16
|
Namiki Y, Fujiwara A, Kihara N, Koda S, Hane K, Yasuda T. Factors Affecting Tautomeric Phenomenon of a Novel Potent Immunosuppressant (FK506) on the Design for Injectable Formulation. Drug Dev Ind Pharm 2008. [DOI: 10.3109/03639049509026645] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
17
|
Pimecrolimus: Skin disposition after topical administration in minipigs in vivo and in human skin in vitro. Eur J Pharm Sci 2008; 33:9-19. [DOI: 10.1016/j.ejps.2007.09.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Revised: 09/11/2007] [Accepted: 09/12/2007] [Indexed: 10/22/2022]
|
18
|
Brittain DEA, Griffiths-Jones CM, Linder MR, Smith MD, McCusker C, Barlow JS, Akiyama R, Yasuda K, Ley SV. Total synthesis of antascomicin B. Angew Chem Int Ed Engl 2006; 44:2732-2737. [PMID: 15806607 DOI: 10.1002/anie.200500174] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Dominic E A Brittain
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Charlotte M Griffiths-Jones
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Michael R Linder
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Martin D Smith
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Catherine McCusker
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Jaqueline S Barlow
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Ryo Akiyama
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Kosuke Yasuda
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| | - Steven V Ley
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK, Fax: (+44) 1223-336-442
| |
Collapse
|
19
|
Zollinger M, Waldmeier F, Hartmann S, Zenke G, Zimmerlin AG, Glaenzel U, Baldeck JP, Schweitzer A, Berthier S, Moenius T, Grassberger MA. PIMECROLIMUS: ABSORPTION, DISTRIBUTION, METABOLISM, AND EXCRETION IN HEALTHY VOLUNTEERS AFTER A SINGLE ORAL DOSE AND SUPPLEMENTARY INVESTIGATIONS IN VITRO. Drug Metab Dispos 2006; 34:765-74. [PMID: 16467136 DOI: 10.1124/dmd.105.007732] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The absorption and disposition of pimecrolimus, a calcineurin inhibitor developed for the treatment of inflammatory skin diseases, was investigated in four healthy volunteers after a single oral dose of 15 mg of [(3)H]pimecrolimus. Supplementary information was obtained from in vitro experiments. Pimecrolimus was rapidly absorbed. After t(max) (1-3 h), its blood concentrations fell quickly to 3% of C(max) at 24 h, followed by a slow terminal elimination phase (average t(1/2) 62 h). Radioactivity in blood decreased more slowly (8% of C(max) at 24 h). The tissue and blood cell distribution of pimecrolimus was high. The metabolism of pimecrolimus in vivo, which could be well reproduced in vitro (human liver microsomes), was highly complex and involved multiple oxidative O-demethylations and hydroxylations. In blood, pimecrolimus was the major radiolabeled component up to 24 h (49% of radioactivity area under the concentration-time curve(0-24) h), accompanied by a large number of minor metabolites. The average fecal excretion of radioactivity between 0 and 240 h amounted to 78% of dose and represented predominantly a complex mixture of metabolites. In urine, 0 to 240 h, only about 2.5% of the dose and no parent drug was excreted. Hence, pimecrolimus was eliminated almost exclusively by oxidative metabolism. The biotransformation of pimecrolimus was largely catalyzed by CYP3A4/5. Metabolite pools generated in vitro showed low activity in a calcineurin-dependent T-cell activation assay. Hence, metabolites do not seem to contribute significantly to the pharmacological activity of pimecrolimus.
Collapse
Affiliation(s)
- Markus Zollinger
- Novartis Pharma AG, WKL-135.2.21, P.O. box, CH-4002 Basel, Switzerland.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Chen YL, Hirabayashi H, Akhtar S, Pelzer M, Kobayashi M. Simultaneous determination of three isomeric metabolites of tacrolimus (FK506) in human whole blood and plasma using high performance liquid chromatography–tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 830:330-41. [PMID: 16318929 DOI: 10.1016/j.jchromb.2005.11.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Revised: 11/04/2005] [Accepted: 11/09/2005] [Indexed: 10/25/2022]
Abstract
An ammonium-adduct based liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the simultaneous determination of three isomeric metabolites of tacrolimus (FK506), 13-O-demethylated (M1), 31-O-demethylated (M2) and 15-O-demethylated (M3) tacrolimus in human whole blood and plasma. These metabolites and the internal standards were extracted from biological matrix by methylbutyl ether (MTBE). Separation was achieved on a Genesis C(18) column with a gradient mobile phase elution. Ammonium-adduct ions formed by a Turbo Ionspray in positive ion mode were used to detect each analyte and internal standard. The MS/MS detection was by monitoring the fragmentation of 807.5-->772.4 (m/z) for M1, 807.5-->754.5 (m/z) for both M2 and M3, 795.5-->760.5 (m/z) for IS1 (FR298701) and 961.5-->908.5 (m/z) for IS2 (FR290198) on a triple quadrupole mass spectrometer (Sciex API 3000). The retention times were approximately 4.1 min for M1, 6.8 min for M2, 6.0 min for M3, and 3.9 min for IS1 and 6.4 min for IS2, respectively. The validated dynamic range was 0.2-20 ng/ml for all three metabolites based on a sample volume of 0.25-ml. The linearity of calibration curves for M1, M2, and M3 in both matrices had a correlation coefficient of >/=0.9984. In whole blood, validation data showed intra-batch (n=6) CVs of </=5.9% and REs between -4.9 and 3.6% and inter-batch (N=18) CVs of </=4.9% and REs between -3.5 and 1.5% for all three metabolites. In human plasma, validation data showed intra-batch (n=6) CVs of </=7.3% and REs between -5.1 and 7.6% and inter-batch (N=18) CVs of </=6.6% and REs between -0.3 and 4.7% for all three metabolites. Extraction recoveries were 72% for M1, 87% for M2, 69% for M3, 79% for IS1, and 74% for IS2 from blood; and 94% for M1, 96% for M2, 98% for M3, 92% for IS1, and 93% for IS2 from plasma. All three metabolites in human blood and plasma were stable for three freeze-thaw cycles, or 24-h ambient storage, or 12 months storage at approximately -80 degrees C. Extracted samples were stable for at least 50h at room temperature (RT). This method has been successfully used to analyze whole blood and plasma samples from human pharmacokinetic studies. Several key factors affecting the performance of the assay methods have also been addressed briefly.
Collapse
Affiliation(s)
- Yu-Luan Chen
- Astellas Research Institute of America, Northwestern University Research Park, 1801 Maple Avenue, Evanston, IL 60201, USA.
| | | | | | | | | |
Collapse
|
21
|
On the reactivity of ascomycin at the binding domain. Part 3: Reactivity of the binding domain towards diazomethane. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
22
|
Brittain DEA, Griffiths-Jones CM, Linder MR, Smith MD, McCusker C, Barlow JS, Akiyama R, Yasuda K, Ley SV. Total Synthesis of Antascomicin B. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200500174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
23
|
Baumann K, Bacher M, Steck A, Wagner T. On the reactivity of ascomycin at the binding domain. Part 2: Hydroxide mediated rearrangement reactions. Tetrahedron 2004. [DOI: 10.1016/j.tet.2004.05.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
24
|
Baumann K, Bacher M, Damont A, Steck A. Selective transformation of ascomycin into 11-epi-ascomycin. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2003.10.199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
25
|
Baumann K, Bacher M, Damont A, Högenauer K, Steck A. On the reactivity of ascomycin at the binding domain. Part 1: Liberation of the tricarbonyl portion of ascomycin. Tetrahedron 2003. [DOI: 10.1016/j.tet.2003.10.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
26
|
Lhoëst GJ, Gougnard TY, Verbeeck RK, Maton N, Dehoux JP, Wallemacq P, Schüler W, Latinne D. Isolation from pig liver microsomes, identification by tandem mass spectrometry and in vitro immunosuppressive activity of an SDZ-RAD 17,18,19,20,21,22-tris-epoxide. JOURNAL OF MASS SPECTROMETRY : JMS 2000; 35:454-460. [PMID: 10767777 DOI: 10.1002/(sici)1096-9888(200003)35:3<454::aid-jms959>3.0.co;2-k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Macrolide immunosuppressive drugs such as tacrolimus (FK506) and sirolimus (rapamycin) are compounds largely used in modern immunosuppressive therapy and considered as powerful immunosuppressive agents. Some of these molecules are still under clinical development as, for example, SDZ-RAD (40-O-(2-hydroxyethyl)rapamycin), an immunosuppressive drug closely related to rapamycin. SDZ-RAD has a molecular mass of 957.57 Da (C53H83NO14) and shares the same common intracellular receptor as tacrolimus, the FK-506 binding protein (FKBP-12). SDZ-RAD exerts its pharmacological effect by binding to a different effector protein, inhibits the S6p 70-kinase and interrupts a different signal transduction pathway than tacrolimus. Both SDZ-RAD and rapamycin are metabolized mainly by the cytochrome P-450 3A4-dependent mixed function oxygenase enzyme system to hydroxylated and demethylated metabolites. We describe here the isolation from pig liver microsomes of a novel SDZ-RAD metabolite identified by electrospray tandam mass spectrometry as a new SDZ-RAD 17,18,19,20,21,22-tris-epoxide metabolite. The in vitro immunosuppressive activity as measured by the mixed lymphocyte reaction is more or less comparable to that of SDZ-RAD, although its pharmacological mode of action may be different from that classically described for rapamycin.
Collapse
Affiliation(s)
- G J Lhoëst
- Department of Pharmaceutical Sciences--UCL, Brussels, Belgium.
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Brands KMJ, Dolling UH, Jobson RB, Marchesini G, Reamer RA, Williams JM. Mild Aryl Ether Formation in the Semisynthesis of the Novel Macrolide Immunosuppressant L-732,531. J Org Chem 1998. [DOI: 10.1021/jo980451q] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Karel M. Jos Brands
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| | - Ulf-H. Dolling
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| | - Ronald B. Jobson
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| | - George Marchesini
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| | - Robert A. Reamer
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| | - J. Michael Williams
- Merck Research Laboratories, Department of Process Research, P.O. Box 2000, Rahway, New Jersey 07065
| |
Collapse
|
28
|
Okamoto Y, Kiriyama K, Namiki Y, Matsushita J, Fujioka M, Yasuda T. Degradation kinetics and isomerization of cefdinir, a new oral cephalosporin, in aqueous solution. 2. Hydrolytic degradation pathway and mechanism for beta-lactam ring opened lactones. J Pharm Sci 1996; 85:984-9. [PMID: 8877891 DOI: 10.1021/js950447j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hydrolysis of cefdinir leads to pH-dependent isomerizations and beta-lactam ring-opening. Lactam ring opened gamma-lactones were produced as a mixture of four diastereoisomers based on the lactone methyl, and C-6 isomerizations in acidic to neutral solutions. Cefdinir and its 7-epimer were hydrolyzed to clarify the pathway leading to these lactones and the mechanism of C-6 epimerization with the aid of chiral separation techniques. Chiral separation using a bovine serum albumin column was employed to detect the beta-lactam ring opened products of cefdinir and its 7-epimer; the C-6 and C-7 isomerization was thereby observed; however, it was found to be pH-dependent at pH > or = 9. Optical activity detection applied to the lactones produced from cefdinir and its 7-epimer demonstrated that the corresponding peaks of these lactones were enantiomeric pairs. In addition, the smallest rate constant at pH 4 was observed for C-6 epimerization of the lactones, and it was found to proceed without deprotonation at C-6 by 1H-NMR spectroscopy. From the results of these studies, a plausible mechanism for C-6 epimerization has been proposed. Additionally, it was confirmed that two degradation pathways were involved during hydrolysis of cefdinir to the lactone.
Collapse
Affiliation(s)
- Y Okamoto
- Quality Assurance Laboratory, Fujisawa Pharmaceutical Co., Ltd., Osaka, Japan
| | | | | | | | | | | |
Collapse
|
29
|
Akashi T, Nefuji T, Yoshida M, Hosoda J. Quantitative determination of tautomeric FK506 by reversed-phase liquid chromatography. J Pharm Biomed Anal 1996; 14:339-46. [PMID: 8851758 DOI: 10.1016/0731-7085(95)01605-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The quantitative determination of FK506, an immunosuppressant for organ transplants, was studied by using reversed-phase high performance liquid chromatography. There were three peaks corresponding to FK506 and its tautomeric compounds on the chromatogram obtained from aqueous solution. Interconversion among these compounds due to epimerization occurs and then reaches an equilibrium in aqueous solution. An increase in the water content in water-solvent solutions caused by the peak areas of FK506 and Tautomer I to decrease and that of Tautomer II to increase. For quantitative analyses of aqueous solutions this creates a problem because the composition of the mixture at equilibrium varies with the water content. A simple method, using a solution of polyoxyethylene lauryl alcohol ether (Brij-35) as a diluent, has been developed to provide a constant equilibrium. By diluting the sample with the Brij-35 diluent, it is possible to quantify FK506 in aqueous solutions. The reliability of the proposed method was confirmed with samples extracted from fermentation broth.
Collapse
Affiliation(s)
- T Akashi
- Fermentation Development Laboratories, Fujisawa Pharmaceutical Co., Ltd., Aichi, Japan
| | | | | | | |
Collapse
|
30
|
Determination of the immunosuppressive drug tacrolimus in its dosage forms by high-performance liquid chromatography. Chromatographia 1995. [DOI: 10.1007/bf02290354] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
31
|
Baumann K, Oberhauser B, Grassberger M, Haidl G, Schulz G. Synthesis and oxidative cleavage of the major equilibrium products of ascomycin and FK 506. Tetrahedron Lett 1995. [DOI: 10.1016/0040-4039(95)00220-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
32
|
Zarnt T, Lang K, Burtscher H, Fischer G. Time-dependent inhibition of peptidylprolyl cis-trans-isomerases by FK506 is probably due to cis-trans isomerization of the inhibitor's imide bond. Biochem J 1995; 305 ( Pt 1):159-64. [PMID: 7529995 PMCID: PMC1136444 DOI: 10.1042/bj3050159] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Free in solution, the immunosuppressive compounds cyclosporin A (CsA), FK506, ascomycin and rapamycin are present in many solvents in various slowly interconverting conformations. Together with their cellular receptor proteins, cyclophilin (CyP) and FK506-binding protein (FKBP), however, these inhibitors have been shown to have a homogeneous conformation. The existence of a slow cis-trans interconversion of an imidic bond in the inhibitor molecule during the course of the formation of the CsA-CyP18cy complex (where CyP18cy is human 18 kDa cytosolic CyP) prompted us to investigate the reaction of the peptidomacrolides FK506, ascomycin and rapamycin with two specific binding-proteins in more detail. Since formation of the FK506-FKBP complex results in the inhibition of the peptidylprolyl cis-trans-isomerase activity of the binding protein, we used the enzyme's decrease in enzymic activity to monitor binding of the inhibitors to their enzyme targets. For FK506, the kinetics of inhibition of human 12 kDa cytosolic FKBP (FKBP12cy) were clearly dependent on time. Subsequent to a rapid inactivation reaction, not resolved in its kinetics due to manual mixing, a slow dominant first-order inactivation process with a relaxation time of 1163 s at 10 degrees C was observed. Concomitantly the Ki value of the slow phase dropped 2.6-fold within the first 60 min of incubation. Using the FKBP12cy homologue 25 kDa membrane FKBP (FKBP25mem), a bacterial peptidylprolyl cis-trans-isomerase, the rate and amplitudes of the inhibition reactions were very similar to FKBP12cy. On the other hand, the kinetics and amplitudes of the inhibition of FKBP12cy varied significantly if rapamycin was used as an inhibitor instead of FK 506. Owing to reduced conformation transition in rapamycin upon binding to FKBP12cy, the slow phase during inhibition was significantly decreased in amplitude. A likely reason for this became apparent when the activation-enthalpy and the pH-dependence of the rate constants of the slow phase were determined. We conclude that the cis to trans interconversion of the pipecolinyl bond of the three peptidomacrolides may be responsible for the slow process. There was no indication of a suicide catalysis of this process by FKBPs.
Collapse
Affiliation(s)
- T Zarnt
- Max-Planck-Gesellschaft, Arbeitsgruppe Enzymologie der Peptidbindung, Halle, Germany
| | | | | | | |
Collapse
|
33
|
|
34
|
Zimmer R, Grassberger MA, Baumann K, Schulz G, Haidl E. Synthetic modifications of ascomycin - I. A chemoselective removal of the cyclohexyl residue of ascomycin. Tetrahedron 1994. [DOI: 10.1016/s0040-4020(01)85679-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|