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Li T, Sun F, Liu Y, Su L, Shi P, Li X, Liu S, Wang C, Shen L, Cao Y, Wang S. Pharmacokinetic and Bioequivalence Study of Eldecalcitol Soft Capsules in Healthy Chinese Subjects. Clin Pharmacol Drug Dev 2022; 11:1474-1480. [PMID: 36018219 PMCID: PMC10087228 DOI: 10.1002/cpdd.1159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/26/2022] [Indexed: 01/28/2023]
Abstract
Eldecalcitol is a novel active vitamin D3 1,25(OH)2 D3 derivative used in the treatment of osteoporosis. To investigate and compare the pharmacokinetic and bioequivalent profiles of two eldecalcitol soft capsule formulations at a single dose of 0.75 µg in healthy Chinese volunteers, we conducted a randomized single-dose, open-label, two-period crossover study under fasting and fed conditions. Eligible subjects were randomly assigned to receive reference eldecalcitol soft capsules or test capsules in the first treatment period and to receive another formulation in the second period. Serial blood samples were collected for pharmacokinetic analysis. Adverse events were recorded. In total, 28 healthy subjects were enrolled in the fasting trial and 30 subjects were enrolled in the fed trial. The geometric mean ratios of the test formulation to the reference formulation for Cmax , AUC0-t , and AUC0-∞ were 94.2%, 94.0%, and 103.3%, respectively, under fasting conditions and 100.1%, 97.3%, and 96.0%, respectively, under fed conditions. No severe adverse events were observed. The results showed that the test and reference eldecalcitol formulations were bioequivalent and well tolerated in healthy Chinese subjects under fasting and fed conditions.
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Affiliation(s)
- Ting Li
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Feifei Sun
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yanping Liu
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Lingping Su
- Wenzhou Haihe Pharmaceutical Co., Ltd, Wenzhou, China
| | - Ping Shi
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xin Li
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shuqin Liu
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Chenjing Wang
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Linjing Shen
- Wenzhou Haihe Pharmaceutical Co., Ltd, Wenzhou, China
| | - Yu Cao
- Phase I Clinical Trials Center, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Shumin Wang
- Pharmacy Department of Beijing Chao-yang Hospital, Capital Medical University, Beijing, China
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Yasuda K, Nishikawa M, Mano H, Takano M, Kittaka A, Ikushiro S, Sakaki T. Development of In Vitro and In Vivo Evaluation Systems for Vitamin D Derivatives and Their Application to Drug Discovery. Int J Mol Sci 2021; 22:ijms222111839. [PMID: 34769269 PMCID: PMC8584323 DOI: 10.3390/ijms222111839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/30/2022] Open
Abstract
We have developed an in vitro system to easily examine the affinity for vitamin D receptor (VDR) and CYP24A1-mediated metabolism as two methods of assessing vitamin D derivatives. Vitamin D derivatives with high VDR affinity and resistance to CYP24A1-mediated metabolism could be good therapeutic agents. This system can effectively select vitamin D derivatives with these useful properties. We have also developed an in vivo system including a Cyp27b1-gene-deficient rat (a type I rickets model), a Vdr-gene-deficient rat (a type II rickets model), and a rat with a mutant Vdr (R270L) (another type II rickets model) using a genome editing method. For Cyp27b1-gene-deficient and Vdr mutant (R270L) rats, amelioration of rickets symptoms can be used as an index of the efficacy of vitamin D derivatives. Vdr-gene-deficient rats can be used to assess the activities of vitamin D derivatives specialized for actions not mediated by VDR. One of our original vitamin D derivatives, which displays high affinity VDR binding and resistance to CYP24A1-dependent metabolism, has shown good therapeutic effects in Vdr (R270L) rats, although further analysis is needed.
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Affiliation(s)
- Kaori Yasuda
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan; (K.Y.); (H.M.)
| | - Miyu Nishikawa
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan; (M.N.); (S.I.)
| | - Hiroki Mano
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan; (K.Y.); (H.M.)
| | - Masashi Takano
- Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo 173-8605, Japan; (M.T.); (A.K.)
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo 173-8605, Japan; (M.T.); (A.K.)
| | - Shinichi Ikushiro
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan; (M.N.); (S.I.)
| | - Toshiyuki Sakaki
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu 939-0398, Toyama, Japan; (K.Y.); (H.M.)
- Correspondence:
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Rendic SP, Peter Guengerich F. Human cytochrome P450 enzymes 5-51 as targets of drugs and natural and environmental compounds: mechanisms, induction, and inhibition - toxic effects and benefits. Drug Metab Rev 2019; 50:256-342. [PMID: 30717606 DOI: 10.1080/03602532.2018.1483401] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cytochrome P450 (P450, CYP) enzymes have long been of interest due to their roles in the metabolism of drugs, pesticides, pro-carcinogens, and other xenobiotic chemicals. They have also been of interest due to their very critical roles in the biosynthesis and metabolism of steroids, vitamins, and certain eicosanoids. This review covers the 22 (of the total of 57) human P450s in Families 5-51 and their substrate selectivity. Furthermore, included is information and references regarding inducibility, inhibition, and (in some cases) stimulation by chemicals. We update and discuss important aspects of each of these 22 P450s and questions that remain open.
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Affiliation(s)
| | - F Peter Guengerich
- b Department of Biochemistry , Vanderbilt University School of Medicine , Nashville , TN , USA
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Hirota Y, Nakagawa K, Isomoto K, Sakaki T, Kubodera N, Kamao M, Osakabe N, Suhara Y, Okano T. Eldecalcitol is more effective in promoting osteogenesis than alfacalcidol in Cyp27b1-knockout mice. PLoS One 2018; 13:e0199856. [PMID: 30281599 PMCID: PMC6169848 DOI: 10.1371/journal.pone.0199856] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 09/01/2018] [Indexed: 01/29/2023] Open
Abstract
Calcium (Ca) absorption from the intestinal tract is promoted by active vitamin D (1α,25D3). Vitamin D not only promotes Ca homeostasis, but it also inhibits bone resorption and promotes osteogenesis, thus playing a role in the maintenance of normal bone metabolism. Because 1α,25D3 plays an important role in osteogenesis, vitamin D formulations, such as alfacalcidol (ALF) and eldecalcitol (ELD), are used for treating osteoporosis. While it is known that, in contrast to ALF, ELD is an active ligand that directly acts on bone, the reason for its superior osteogenesis effects is unknown. Cyp27b1-knockout mice (Cyp27b1-/-mice) are congenitally deficient in 1α,25D3 and exhibit marked hypocalcemia and high parathyroid hormone levels, resulting in osteodystrophy involving bone hypocalcification and growth plate cartilage hypertrophy. However, because the vitamin D receptor is expressed normally in Cyp27b1-/-mice, they respond normally to 1α,25D3. Accordingly, in Cyp27b1-/-mice, the pharmacological effects of exogenously administered active vitamin D derivatives can be analyzed without being affected by 1α,25D3. We used Cyp27b1-/-mice to characterize and clarify the superior osteogenic effects of ELD on the bone in comparison with ALF. The results indicated that compared to ALF, ELD strongly induces ECaC2, calbindin-D9k, and CYP24A1 in the duodenum, promoting Ca absorption and decreasing the plasma concentration of 1α,25D3, resulting in improved osteogenesis. Because bone morphological measurements demonstrated that ELD has stronger effects on bone calcification, trabecular formation, and cancellous bone density than ALF, ELD appears to be a more effective therapeutic agent for treating postmenopausal osteoporosis, in which cancellous bone density decreases markedly. By using Cyp27b1-/-mice, this study was the first to succeed in clarifying the osteogenic effect of ELD without any influence of endogenous 1α,25D3. Furthermore, ELD more strongly enhanced bone mineralization, trabecular proliferation, and cancellous bone density than did ALF. Thus, ELD is expected to show an effect on postmenopausal osteoporosis, in which cancellous bone mineral density decreases markedly. In the future, this study may enable the development of next-generation active vitamin D derivatives with higher affinity for bone than ELD.
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Affiliation(s)
- Yoshihisa Hirota
- Laboratory of Biochemistry, Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Fukasaku, Minuma-ku, Saitama, Japan
- Laboratory of Hygienic Sciences, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, Kobe, Japan
| | - Kimie Nakagawa
- Laboratory of Hygienic Sciences, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, Kobe, Japan
| | - Keigo Isomoto
- Laboratory of Hygienic Sciences, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, Kobe, Japan
| | - Toshiyuki Sakaki
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, Kurokawa, Imizu, Toyama, Japan
| | - Noboru Kubodera
- International Institute of Active Vitamin D Analogs, Sankeidai, Mishima, Shizuoka, Japan
| | - Maya Kamao
- Laboratory of Hygienic Sciences, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, Kobe, Japan
| | - Naomi Osakabe
- Food and Nutrition Laboratory, Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Fukasaku, Minuma-ku, Saitama, Japan
| | - Yoshitomo Suhara
- Laboratory of Organic Synthesis and Medicinal Chemistry, Department of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, Fukasaku, Minuma-ku, Saitama, Japan
| | - Toshio Okano
- Laboratory of Hygienic Sciences, Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada-ku, Kobe, Japan
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Yasuda K, Tohyama E, Takano M, Kittaka A, Ohta M, Ikushiro S, Sakaki T. Metabolism of 2α-[2-(tetrazol-2-yl)ethyl]-1α,25-dihydroxyvitamin D 3 by CYP24A1 and biological activity of its 24R-hydroxylated metabolite. J Steroid Biochem Mol Biol 2018; 178:333-339. [PMID: 29425808 DOI: 10.1016/j.jsbmb.2018.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 12/29/2022]
Abstract
Our previous study revealed that the 2α-substituted vitamin D analog 2α-[2-(tetrazol-2-yl)ethyl]-1α,25(OH)2D3 (AH-1) exhibited a higher osteocalcin promoter transactivation activity in human osteosarcoma cells and a greater effect on bone mineral density in a rat model of osteoporosis than 1α,25(OH)2D3 without increasing blood calcium concentration. Thus, we hypothesized that AH-1 could be a promising therapeutic agent for osteoporosis without any serious side effects. In this study, we compared the CYP24A1-dependent metabolism of AH-1 with that of 1α,25(OH)2D3. The resistance to CYP24A1-dependent metabolism could be an important property of vitamin D analogs in prolonging their biological effects. A kinetic analysis was performed using a membrane fraction prepared from recombinant E. coli expressing human CYP24A1. The kcat/Km (μM-1 min-1) value for AH-1 was 31% of that for 1α,25(OH)2D3, suggesting that AH-1 is not as resistant to CYP24A1-dependent metabolism as the other C2-substituted vitamin D analogs such as eldecalcitol [2β-hydroxypropoxy-1α,25(OH)2D3]. The major metabolite of AH-1 was the 24R-hydroxylated metabolite, which had high vitamin D receptor (VDR) binding affinity and high HL-60 cell differentiation activity similar to AH-1 itself. In contrast, 1α,25(OH)2D3 was metabolized by multistep monooxygenation reactions, which led to the loss of affinity for VDR. Thus, the greater therapeutic effects of AH-1 than those of 1α,25(OH)2D3 in in vivo studies using osteoporosis rat models may be due to 24R-hydroxy-AH-1 whose VDR affinity was 91% of that of AH-1.
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Affiliation(s)
- Kaori Yasuda
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan; Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Eri Tohyama
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Masashi Takano
- Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo 173-8605, Japan
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo 173-8605, Japan
| | - Miho Ohta
- Development Nourishment Department, Soai University, 4-4-1 Nankonaka, Suminoe, Osaka 559-0033, Japan
| | - Shinichi Ikushiro
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Toshiyuki Sakaki
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan; Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.
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Mano H, Ikushiro S, Saito N, Kittaka A, Sakaki T. Development of a highly sensitive in vitro system to detect and discriminate between vitamin D receptor agonists and antagonists based on split-luciferase technique. J Steroid Biochem Mol Biol 2018; 178:55-59. [PMID: 29101064 DOI: 10.1016/j.jsbmb.2017.10.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/20/2017] [Accepted: 10/31/2017] [Indexed: 11/19/2022]
Abstract
Split-luciferase techniques are widely used to detect protein-protein interaction and bioactive small molecules including some hormones and vitamins. Previously, we successfully expressed chimeric proteins of luciferase and the ligand binding domain (LBD) of the vitamin D receptor (VDR), LucC-LBD-LucN in COS-7 cells. The LucC-LBD-LucN biosensor was named split-luciferase vitamin D biosensor (SLDB). This biosensor can detect and discriminate between VDR agonists and antagonists in mammalian cells. In this study, we established an in vitro screening system for VDR ligands using the SLDB proteins expressed in Escherichia coli (E. coli) cells. Our in vitro screening system using cell lysate of recombinant E. coli cells could be completed within 30min, and its activity was unchanged after 10 freeze-thaw cycles. This highly sensitive and convenient system would be quite useful to screen VDR ligands with therapeutic potential for various bone-related diseases, age-related cognitive disorders, cancer, and immune disorders. In addition, our system might be applicable to diagnostic measurement of serum concentrations of 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3.
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Affiliation(s)
- Hiroki Mano
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Shinichi Ikushiro
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Nozomi Saito
- Faculty of Pharmaceutical Sciences, Teikyo University, Itabashi, Tokyo 173-8605 Japan
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Itabashi, Tokyo 173-8605 Japan
| | - Toshiyuki Sakaki
- Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.
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Takano M, Yasuda K, Tohyama E, Higuchi E, Sakaki T, Kittaka A. Synthesis of the CYP24A1 major metabolite of 2α-[2-(tetrazol-2-yl)ethyl]-1α,25-dihydroxyvitamin D 3. J Steroid Biochem Mol Biol 2017; 173:75-78. [PMID: 27923594 DOI: 10.1016/j.jsbmb.2016.11.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 11/01/2016] [Accepted: 11/30/2016] [Indexed: 11/25/2022]
Abstract
Previously, we found that 2α-[2-(tetrazol-2-yl)ethyl]-1α,25-dihydroxyvitamin D3 (AH-1) showed higher osteocalcin promoter transactivation activity in human osteosarcoma (HOS) cells and a greater therapeutic effect on ovariectomized (OVX) rats for enhancing bone mineral density than those of 1α,25(OH)2D3 without hypercalcemic side effects in vivo. Although CYP24A1 catalyzes multi-step oxidations toward the CD-ring side chain of the active vitamin D3 [1α,25(OH)2D3], the CYP24A1-dependent metabolism of AH-1 tended to stop at the first step hydroxylation at the C24-position of AH-1. Interestingly, the metabolite 24-hydroxy-AH-1 [24(OH)AH-1] showed potent VDR binding affinity, and the new chiral center of the 24-position might be the 24R configuration compared with the process of the natural 1α,25(OH)2D3 catabolism. This time, (24R)-2α-[2-(tetrazol-2-yl)ethyl]-1α,24,25-trihydroxyvitamin D3 [(24R-OH)AH-1] was synthesized as a candidate for the major metabolite of AH-1 using the Trost Pd-mediated coupling reaction between A-ring and CD-ring precursors to identify the metabolite and evaluate its biological activity. We confirmed that the CYP24A1-dependent major metabolite of AH-1 was (24R-OH)AH-1 by HPLC analyses.
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Affiliation(s)
- Masashi Takano
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
| | - Kaori Yasuda
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Eri Tohyama
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Erika Higuchi
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
| | - Toshiyuki Sakaki
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan.
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan.
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Yasuda K, Iwanaga Y, Ogawa K, Mano H, Ueno S, Kimoto S, Ohta M, Kamakura M, Ikushiro S, Sakaki T. Human hepatic metabolism of the anti-osteoporosis drug eldecalcitol involves sterol C4-methyl oxidase. Pharmacol Res Perspect 2015; 3:e00120. [PMID: 26038696 PMCID: PMC4448988 DOI: 10.1002/prp2.120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 11/28/2014] [Accepted: 11/30/2014] [Indexed: 11/22/2022] Open
Abstract
The metabolism of eldecalcitol (ED-71), a 2β-hydroxypropoxylated analog of the active form of vitamin D3 was investigated by using in vitro systems. ED-71 was metabolized to 1α,2β,25-trihydroxyvitamin D3 (1α,2β,25(OH)3D3) in human small intestine and liver microsomes. To identify the enzymes involved in this metabolism, we examined NADPH-dependent metabolism by recombinant P450 isoforms belonging to the CYP1, 2, and 3 families, and revealed that CYP3A4 had the activity. However, the CYP3A4 -specific inhibitor, ketoconazole, decreased the activity in human liver microsomes by only 36%, suggesting that other enzymes could be involved in ED-71 metabolism. Because metabolism was dramatically inhibited by cyanide, we assumed that sterol C4-methyl oxidase like gene product (SC4MOL) might contribute to the metabolism of ED-71. It is noted that SC4MOL is physiologically essential for cholesterol synthesis. Recombinant human SC4MOL expressed in COS7, Saccharomyces cerevisiae, or Escherichia coli cells converted ED-71 to 1α,2β,25(OH)3D3. Furthermore, we evaluated the metabolism of ED-71 by recombinant CYP24A1, which plays an important role in the metabolism of the active form of vitamin D3 (1α,25(OH)2D3) and its analogs. The kcat/Km value for 24- or 23-hydroxylation of ED-71 was only 3% of that for 1α,25(OH)2D3, indicating that ED-71 was resistant to CYP24A1-dependent catabolism. Among the three enzymes catalyzing ED-71, SC4MOL appears to be most important in the metabolism of ED-71. To the best of our knowledge, this is the first study showing that SC4MOL can function as a drug-metabolizing enzyme. The yeast and E. coli expression systems for SC4MOL could be useful for structure-function analyses of SC4MOL.
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Affiliation(s)
- Kaori Yasuda
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Yuasa Iwanaga
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Kazuaki Ogawa
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Hiroki Mano
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Sera Ueno
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Shutaro Kimoto
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Miho Ohta
- Development Nourishment Department, Soai University 4-4-1 Nankonaka, Suminoe, Osaka, 559-0033, Japan
| | - Masaki Kamakura
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Shinichi Ikushiro
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
| | - Toshiyuki Sakaki
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan
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Takano M, Sawada D, Yasuda K, Nishikawa M, Takeuchi A, Takagi KI, Horie K, Reddy GS, Chen TC, Sakaki T, Kittaka A. Synthesis and metabolic studies of 1α,2α,25-, 1α,4α,25- and 1α,4β,25-trihydroxyvitamin D3. J Steroid Biochem Mol Biol 2015; 148:34-7. [PMID: 25263656 DOI: 10.1016/j.jsbmb.2014.09.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 09/17/2014] [Accepted: 09/22/2014] [Indexed: 11/24/2022]
Abstract
Three different A-ring perhydroxylated trihydroxyvitamin D3 metabolites were synthesized from their appropriate A-ring precursors and CD-ring for their potential therapeutic applications. We first chemically synthesized 1α,2α,25-trihydroxyvitamin D3 [1α,2α,25(OH)3D3] to study its VDR binding affinity because this metabolite is a product of recombinant human CYP3A4 catalysis when 2α-(3-hydroxypropoxy)-1α,25-dihydroxyvitamin D3 (O2C3), a more potent vitamin D receptor (VDR) binder than 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], is used as the substrate. We found that this metabolite retained 27.3% of the VDR binding affinity compared to 1α,25(OH)2D3. The kcat/Km value of CYP24A1 for 1α,2α,25(OH)3D3 is 60% of that for 1α,25(OH)2D3. Since the biological activity and the metabolic fate of a naturally occurring C4-hydroxylated vitamin D2 metabolite found in the serum of rats treated with pharmacological doses of vitamin D2 have never been described, we next synthesized 1α,4α,25-trihydroxyvitamin D3 and its diastereoisomer, 1α,4β,25-trihydroxyvitamin D3, to study their metabolism and biological activities. Both 4-hydroxylated isomers showed weaker VDR binding affinity than 1α,25(OH)2D3. Although either 4-hydroxylated isomer can be metabolized by CYP24A1 almost at the same level as 1α,25(OH)2D3, their metabolic patterns catalyzed by uridine 5'-diphosphoglucuronosyltransferase (UGT) are different; only the 4α-hydroxylated analog can be metabolized by UGT to produce a glucuronate conjugate. The results provide important information for the synthesis of new novel chemotherapeutic vitamin D analogs which would be less subjective to degradation and therefore more bioavailable than 1α,25(OH)2D3. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.
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Affiliation(s)
- Masashi Takano
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
| | - Daisuke Sawada
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
| | - Kaori Yasuda
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Miyu Nishikawa
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Akiko Takeuchi
- Teijin Institute for Bio-medical Research, Teijin Pharma Ltd., Hino, Tokyo 191-8512, Japan
| | - Ken-Ichiro Takagi
- Teijin Institute for Bio-medical Research, Teijin Pharma Ltd., Hino, Tokyo 191-8512, Japan
| | - Kyohei Horie
- Teijin Institute for Bio-medical Research, Teijin Pharma Ltd., Hino, Tokyo 191-8512, Japan
| | | | - Tai C Chen
- Section of Endocrinology, Diabetes & Nutrition, Boston University School of Medicine, Boston, MA 02118, USA
| | - Toshiyuki Sakaki
- Faculty of Engineering, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
| | - Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan.
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Nesterova G, Malicdan MC, Yasuda K, Sakaki T, Vilboux T, Ciccone C, Horst R, Huang Y, Golas G, Introne W, Huizing M, Adams D, Boerkoel CF, Collins MT, Gahl WA. 1,25-(OH)2D-24 Hydroxylase (CYP24A1) Deficiency as a Cause of Nephrolithiasis. Clin J Am Soc Nephrol 2013; 8:649-57. [PMID: 23293122 DOI: 10.2215/cjn.05360512] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND OBJECTIVES Elevated serum vitamin D with hypercalciuria can result in nephrocalcinosis and nephrolithiasis. This study evaluated the cause of excess 1,25-dihydroxycholecalciferol (1α,25(OH)2D3) in the development of those disorders in two individuals. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Two patients with elevated vitamin D levels and nephrocalcinosis or nephrolithiasis were investigated at the National Institutes of Health (NIH) Clinical Center and the NIH Undiagnosed Diseases Program, by measuring calcium, phosphate, and vitamin D metabolites, and by performing CYP24A1 mutation analysis. RESULTS Both patients exhibited hypercalciuria, hypercalcemia, low parathyroid hormone, elevated vitamin D (1α,25(OH)2D3), normal 25-OHD3, decreased 24,25(OH)2D, and undetectable activity of 1,25(OH)2D-24-hydroxylase (CYP24A1), the enzyme that inactivates 1α,25(OH)2D3. Both patients had bi-allelic mutations in CYP24A1 leading to loss of function of this enzyme. On the basis of dbSNP data, the frequency of predicted deleterious bi-allelic CYP24A1 variants in the general population is estimated to be as high as 4%-20%. CONCLUSIONS The results of this study show that 1,25(OH)2D-24-hydroxylase deficiency due to bi-allelic mutations in CYP24A1 causes elevated serum vitamin D, hypercalciuria, nephrocalcinosis, and renal stones.
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Affiliation(s)
- Galina Nesterova
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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11
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Yasuda K, Ikushiro S, Kamakura M, Takano M, Saito N, Kittaka A, Chen TC, Ohta M, Sakaki T. Human cytochrome P450-dependent differential metabolism among three 2α-substituted-1α,25-dihydroxyvitamin D(3) analogs. J Steroid Biochem Mol Biol 2013; 133:84-92. [PMID: 22982757 DOI: 10.1016/j.jsbmb.2012.09.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Revised: 09/05/2012] [Accepted: 09/07/2012] [Indexed: 11/27/2022]
Abstract
Our previous studies revealed that C2α-substituted-1α,25(OH)(2)D(3) analogs had unique biological activities. For example, 19-nor-2α-(3-hydroxypropyl)-1α,25(OH)(2)D(3) (MART-10), which has a high affinity for vitamin D receptor (VDR), is more bioavailable and more potent than 1α,25(OH)(2)D(3) in inhibiting cancer cell growth and invasion because of its weaker binding to vitamin D binding protein (DBP), and more resistance to CYP24A1-dependent metabolism. In this study, we examined the metabolism of MART-10 and two other 2α-substituted analogs, 2α-(3-hydroxypropoxy)-1α,25(OH)(2)D(3) (O2C3) and 2α-(3-hydroxypropyl)-1α,25(OH)(2)D(3) (O1C3) by using human liver microsomes and human P450s. We demonstrated that O2C3 was converted to 1α,2α,25(OH)(3)D(3) in human liver microsomes, whereas both O1C3 and MART-10 were hardly metabolized. The metabolism of O2C3 was significantly inhibited by ketoconazole, and the recombinant human CYP3A4 converted O2C3 to 1α,2α,25(OH)(3)D(3), which suggests that CYP3A4 is responsible for the metabolism of O2C3 in human liver. The k(cat)/K(m) values of CYP3A4 for O1C3 and MART-10 are much smaller than that for O2C3. The k(cat)/K(m) values of human CYP24A1 for the three analogs are 1% (MART-10), 3% (O2C3), and 4% (O1C3) of that for 1α,25(OH)(2)D(3), indicating that MART-10 is the most resistant to CYP24A1 hydroxylation. On the other hand, 1α,2α,25(OH)(3)D(3), the metabolite of O2C3 by CYP3A4, was metabolized by CYP24A1 via multiple pathways similar to 1α,25(OH)(2)D(3), which suggests that O2C3 can be metabolized by two sequential hydroxylations, first by CYP3A4 and then by CYP24A1 in human body. These results suggest that modification at C-2α position and C-19 demethylenation markedly change metabolic profiles and biological activities of vitamin D analogs.
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Affiliation(s)
- Kaori Yasuda
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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12
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Glebocka A, Chiellini G. A-ring analogs of 1,25-dihydroxyvitamin D3. Arch Biochem Biophys 2012; 523:48-57. [DOI: 10.1016/j.abb.2011.11.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 11/04/2011] [Accepted: 11/07/2011] [Indexed: 01/07/2023]
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13
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Chen TC, Kittaka A. Novel vitamin d analogs for prostate cancer therapy. ISRN UROLOGY 2011; 2011:301490. [PMID: 22084796 PMCID: PMC3195751 DOI: 10.5402/2011/301490] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Accepted: 06/03/2011] [Indexed: 12/14/2022]
Abstract
Prostate cells contain specific receptors for 1α,25-dihydroxyvitamin D [1α,25(OH)2D] or calcitriol, the active form of vitamin D. 1α,25(OH)2D is known to inhibit the proliferation and invasiveness of prostate cancer cells. These findings support the use of 1α,25(OH)2D for prostate cancer therapy. However, 1α,25(OH)2D can cause hypercalcemia, analogs of 1α,25(OH)2D that are less calcemic but exhibit potent antiproliferative activity would be attractive as therapeutic agents. To accomplish these goals, different strategies, based on metabolism, molecular mechanism of actions, and structural modeling, have been taken to modify the structure of vitamin D molecule with the aims to improve the efficacy and decrease the toxicity of vitamin D to treat different diseases. During the past four decades, over 3,000 analogs have been synthesized. In this paper, we discuss the development and the biological analysis of a unique class of vitamin D analogs with a substitution at the carbon 2 of 19-nor-1α,25(OH)2D3 molecule for potential application to the prevention and treatment of prostate cancer as well as other cancers.
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Affiliation(s)
- Tai C Chen
- Boston University School of Medicine, Room M-1022, 715 Albany Street, Boston, MA 02118, USA
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14
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Kittaka A, Sakaki T, Hara H, Yasuda K, Takano M, A. Arai M, Sawada D, Saito H, Takenouchi K, C. Chen T. Studies on the Synthesis and Metabolism of 14-epi-2α-(3-Hydroxypropyl)-19-norvitamin D3 and Its 2β-Isomer. HETEROCYCLES 2010. [DOI: 10.3987/com-10-s(e)40] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Synthesis of 2α-propoxy-1α,25-dihydroxyvitamin D3 and comparison of its metabolism by human CYP24A1 and rat CYP24A1. Bioorg Med Chem 2009; 17:4296-301. [DOI: 10.1016/j.bmc.2009.05.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 05/11/2009] [Accepted: 05/12/2009] [Indexed: 11/19/2022]
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16
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Urushino N, Yasuda K, Ikushiro S, Kamakura M, Ohta M, Sakaki T. Metabolism of 1alpha,25-dihydroxyvitamin D2 by human CYP24A1. Biochem Biophys Res Commun 2009; 384:144-8. [PMID: 19393625 DOI: 10.1016/j.bbrc.2009.04.075] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Accepted: 04/15/2009] [Indexed: 10/20/2022]
Abstract
The metabolism of 1alpha,25-dihydroxyvitamin D2 (1alpha,25(OH)2D2) by human CYP24A1 was examined using the recombinant enzyme expressed in Escherichia coli cells. HPLC analysis revealed that human CYP24A1 produces at least 10 metabolites, while rat CYP24A1 produces only three metabolites, indicating a remarkable species-based difference in the CYP24A1-dependent metabolism of 1alpha,25(OH)2D2 between humans and rats. LC-MS analysis and periodate treatment of the metabolites strongly suggest that human CYP24A1 converts 1alpha,25(OH)2D2 to 1alpha,24,25,26(OH)4D2, 1alpha,24,25,28(OH)4D2, and 24-oxo-25,26,27-trinor-1alpha(OH)D2 via 1alpha,24,25(OH)3D2. These results indicate that human CYP24A1 catalyzes the C24-C25 bond cleavage of 1alpha,24,25(OH)2D2, which is quite effective in the inactivation of the active form of vitamin D2. The combination of hydroxylation at multiple sites and C-C bond cleavage could form a large number of metabolites. Our findings appear to be useful to predict the metabolism of vitamin D2 and its analogs in the human body.
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Affiliation(s)
- Naoko Urushino
- Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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17
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Kittaka A. Structural refinement of seco-steroidal skeleton and the biological activity through nuclear receptors. YAKUGAKU ZASSHI 2008; 128:1235-50. [PMID: 18758137 DOI: 10.1248/yakushi.128.1235] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
1alpha,25-Dihydroxyvitamin D(3) (1) regulates a variety of biological actions through vitamin D receptor (VDR), including calcium and phosphorus homeostasis, bone remodeling, cellular proliferation and differentiation and many other functions. To enhance its potency and to study the structure/function relationship, we synthesized a series of analogs of 1 with a modification at the C-2alpha position. Introducing 2alpha-methyl, 2alpha-(3-hydroxypropyl), or 2alpha-(3-hydroxypropoxy) group increased its binding affinity for the VDR 2- to 4-fold compared to 1. The crystal structures of the VDR bound to these analogs provide a molecular explanation for the interaction between the 2alpha-substituents and water molecules exist in the VDR-ligand binding domain. Based on the accumulated knowledge in VDR agonists, we synthesized 2-substituted analogs of 'double side chain' (gemini), 19-norvitamin D(3) (MART-10), TEI-9647 (VDR antagonist), 1-alkylated vitamin D(3), 14-epi-previtamin D(3) etc. Gemini analogs showed potent HL-60 cell differentiation activity (13-38 times compared to 1), and MART-10 exhibited remarkable antiproliferative activity on PZ-HPV-7 cells even at 10(-10) M. (24S)-2alpha-(3-Hydroxypropoxy)-24-propyl-TEI-9647 showed potent VDR antagonism, and its IC(50) value was 7.4 pM against 10 nM of 1. 1alpha-Methyl-2alpha-(3-hydroxypropyl)-25-hydroxyvitamin D(3) improved the binding affinity for the mutant VDR(Arg274Leu), which causes hereditary vitamin D resistant rickets. 1alpha,25-Dihydroxy-2alpha-methyl-14-epi-previtamin D(3) showed moderate osteocalcin transcriptional activity on HOS cells. We theorize that modification at A-ring alone and in combination with functionalization of the other parts of the vitamin D molecule would provide important new information on the mechanism of vitamin D actions that could lead to the development of new therapeutic regimes for the treatment of various diseases.
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Affiliation(s)
- Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko-cho, Sagamihara City, Japan.
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18
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Kittaka A, Saito N, Honzawa S, Takenouchi K, Ishizuka S, Chen TC, Peleg S, Kato S, Arai MA. Creative synthesis of novel vitamin D analogs for health and disease. J Steroid Biochem Mol Biol 2007; 103:269-76. [PMID: 17223554 DOI: 10.1016/j.jsbmb.2006.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We report new analogs of 1alpha,25-dihydroxyvitamin D(3) (1) in three categories. First, design and synthesis of ligands for a mutant vitamin D receptor (VDR)(Arg274Leu), which possess proper functional groups at both C1alpha and C2alpha positions of 1 to study the biological activity of the mutant VDR. Among our synthetic analogs, 1alpha-methyl-2alpha-(3-hydroxypropyl)-25-hydroxyvitamin D(3) (8) showed 7.3-fold greater transcriptional activity for the VDR(Arg274Leu) than that of 1. Next, we examined the antiproliferative activity of 2-substituted 19-norvitamin D(3) analogs on an immortalized normal prostate cell line, PZ-HPV-7, and we found MART 10 (14) showed the activity even at very low concentration of 10(-10) to 10(-11)M. We also synthesized 25-hydroxy-19-norvitamin D(3) (13) using Julia-type olefination to connect between the C5 and C6 positions, effectively, to test it as a prohormone type agent for antiprostate diseases. Synthesized compound 13 showed potent antiproliferative activity in PZ-HPV-7, which has high 1alpha-hydroxylase activity. Finally, we describe design and synthesis of a new TEI-9647 analog, 2alpha-(3-hydroxypropoxy)-24-propyl-25-dehydro-1alpha-hydroxyvitamin D(3)-26,23-lactone (17), which showed the strongest VDR antagonism. Its IC(50) value is 7.4pM to inhibit differentiation of HL-60 cells induced by 10nM of 1.
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Affiliation(s)
- Atsushi Kittaka
- Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Sagamihara, Kanagawa 199-0195, Japan.
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19
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Hamamoto H, Kusudo T, Urushino N, Masuno H, Yamamoto K, Yamada S, Kamakura M, Ohta M, Inouye K, Sakaki T. Structure-function analysis of vitamin D 24-hydroxylase (CYP24A1) by site-directed mutagenesis: amino acid residues responsible for species-based difference of CYP24A1 between humans and rats. Mol Pharmacol 2006; 70:120-8. [PMID: 16617161 DOI: 10.1124/mol.106.023275] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our previous studies revealed the species-based difference of CYP24A1-dependent vitamin D metabolism. Although human CYP24A1 catalyzes both C-23 and C-24 oxidation pathways, rat CYP24A1 shows almost no C-23 oxidation pathway. We tried to identify amino acid residues that cause the species-based difference by site-directed mutagenesis. In the putative substrate-binding regions, amino acid residue of rat CYP24A1 was converted to the corresponding residue of human CYP24A1. Among eight mutants examined, T416M and I500T showed C-23 oxidation pathway. In addition, the mutant I500F showed quite a different metabolism of 1alpha,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] from both human and rat CYP24A1. These results strongly suggest that the amino acid residues at positions 416 and 500 play a crucial role in substrate binding and greatly affect substrate orientation. A three-dimensional model of CYP24A1 indicated that the A-ring and triene part of 1alpha,25(OH)2D3 could be located close to amino acid residues at positions 416 and 500, respectively. Our findings provide useful information for the development of new vitamin D analogs for clinical use.
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Affiliation(s)
- Hiromi Hamamoto
- Biotechnology Research Center, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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20
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Honzawa S, Hirasaka K, Yamamoto Y, Peleg S, Fujishima T, Kurihara M, Saito N, Kishimoto S, Sugiura T, Waku K, Takayama H, Kittaka A. Design, synthesis and biological evaluation of novel 1α,25-dihydroxyvitamin D3 analogues possessing aromatic ring on 2α-position. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.08.116] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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