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Miura A, Narita Y, Sugawara T, Shimizu H, Itoh H. Mizoribine Promotes Molecular Chaperone HSP60/HSP10 Complex Formation. Int J Mol Sci 2024; 25:6452. [PMID: 38928158 PMCID: PMC11203801 DOI: 10.3390/ijms25126452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/03/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024] Open
Abstract
It has been reported that Mizoribine is an immunosuppressant used to suppress rejection in renal transplantation, nephrotic syndrome, lupus nephritis, and rheumatoid arthritis. The molecular chaperone HSP60 alone induces inflammatory cytokine IL-6 and the co-chaperone HSP10 alone inhibits IL-6 induction. HSP60 and HSP10 form a complex in the presence of ATP. We analyzed the effects of Mizoribine, which is structurally similar to ATP, on the structure and physiological functions of HSP60-HSP10 using Native/PAGE and transmission electron microscopy. At low concentrations of Mizoribine, no complex formation of HSP60-HSP10 was observed, nor was the expression of IL-6 affected. On the other hand, high concentrations of Mizoribine promoted HSP60-HSP10 complex formation and consequently suppressed IL-6 expression. Here, we propose a novel mechanism of immunosuppressive action of Mizoribine.
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Affiliation(s)
- Atsuko Miura
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
- Department of Life Science, Akita Cerebrospinal and Cardiovascular Center, Akita 010-0874, Japan
| | - Yukihiko Narita
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Taku Sugawara
- Department of Life Science, Akita Cerebrospinal and Cardiovascular Center, Akita 010-0874, Japan
| | - Hiroaki Shimizu
- Department of Neurosurgery, Akita University Graduate School of Medicine, Akita 010-8543, Japan
| | - Hideaki Itoh
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan
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Nagai K. Immunosuppressive Agent Options for Primary Nephrotic Syndrome: A Review of Network Meta-Analyses and Cost-Effectiveness Analysis. Medicina (B Aires) 2023; 59:medicina59030601. [PMID: 36984602 PMCID: PMC10054564 DOI: 10.3390/medicina59030601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 03/13/2023] [Accepted: 03/16/2023] [Indexed: 03/22/2023] Open
Abstract
Therapeutic options with immunosuppressive agents for glomerular diseases have widened with refinements to the Kidney Disease Improving Global Outcomes (KDIGO) guidelines from 2012 to 2021. However, international guidelines do not necessarily match the reality in each country. Expensive therapies such as rituximab and calcineurin inhibitors are sometimes inaccessible to patients with refractory nephrotic syndrome due to cost or regulations. Under the Japanese medical insurance system, rituximab is accessible but still limited to steroid-dependent patients who developed idiopathic nephrotic syndrome in childhood. Based on international KDIGO guidelines and other national guidelines, possible applications of immunosuppressive agents for nephrotic syndrome are comprehensively examined in this review. While rituximab has become the mainstay of immunosuppressive therapy for nephrotic syndrome, clinical trials have indicated that options such as cyclophosphamide, calcineurin inhibitors, and mycophenolate mofetil would be preferable. Given the rising number of patients with nephrotic syndrome worldwide, KDIGO guidelines mention the need for further consideration of cost-effectiveness. If the new option of rituximab is to be the first choice in combination with steroids for nephrotic syndrome, its cost-effectiveness should also be verified. Among the few studies examining the cost-effectiveness of treatments for nephrotic syndrome, administration of rituximab to young adults has been shown to be cost-beneficial, at least in Japan. However, further large-scale studies involving multiple facilities are needed to verify such findings. Network meta-analyses have concluded that the efficacy of rituximab remains controversial and confirmation through high-quality studies of large cohorts is needed. To this end, the mechanisms of action underlying immunosuppressive agents, both old and new, need to be understood and experience must be accumulated to evaluate possible effects and side effects.
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Affiliation(s)
- Kei Nagai
- University of Tsukuba Hospital Hitachi Social Cooperation Education Research Center, Hitachi 317-0077, Ibaraki, Japan
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Dong Z, Zhou J, Xu Z, Ni Z, He Y, Lin H, Jiang G, Sun X, Zhang L, Chen X. Efficacy and Safety of Mizoribine in comparison with Cyclophosphamide for Treatment of Refractory Nephrotic Syndrome: Protocol for a Multi-center, Controlled, Open-label, Randomized Controlled Trial (Preprint). JMIR Res Protoc 2023. [PMID: 36990111 DOI: 10.2196/46101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023] Open
Abstract
BACKGROUND Nephrotic syndrome that is resistant to steroidal therapy is termed refractory nephrotic syndrome (RNS), a condition that is associated with an increased risk of end-stage renal disease (ESRD). Immunosuppressants are utilized to treat RNS, however prolonged may lead to significant adverse effects. Mizoribine (MZR) is a novel agent used in long-term immunosuppressive therapy that has few adverse effects, but data on its long-term use in patients with RNS are unavailable. OBJECTIVE We propose a trial to examine the efficacy and safety of MZR compared to cyclophosphamide (CYC) in Chinese adult patients with RNS. METHODS This is a multi-center, randomized, controlled interventional study with a screening phase (1 week) and a treatment phase (52 weeks). This study was reviewed and approved by the Medical Ethics Committees of all 34 medical centers. Patients with RNS consented to participation, and were enrolled and randomized into an MZR group or a CYC group (1:1 ratio), with each group receiving tapering doses of oral corticosteroids. Participants were assessed for adverse effects and collection of laboratory results at 8 visits during the treatment phase on week-4, week-8, week-12, week-16, week-20, week-32, week-44, and week-52 (exit visit). Participants were able to withdraw voluntarily and investigators were required to remove patients when there were safety concerns or deviations from protocol. RESULTS The study started in November 2014, and was completed in March 2019. A total of 239 participants from 34 hospitals in China were enrolled. Data analysis is completed. The results are waiting to be finalized by Center for Drug Evaluation. CONCLUSIONS The purpose of the current study is to evaluate the efficacy and safety of MZR in comparison with CYC for treatment of RNS in Chinese adult patients with glomerular diseases. It is the longest lasting and largest randomized controlled trial to examine MZR in Chinese patients. The results can help determine whether RNS should be considered as an additional indication for MZR treatment in China. CLINICALTRIAL ClinicalTrials.gov Register, NCT02257697. Registered 2014-10-01, https://clinicaltrials.gov/ct2/show/NCT02257697?term=MZR&rank=2.
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Affiliation(s)
- Zheyi Dong
- Department of Nephrology, First Medical Center of Chinese PLA General Hospital, Nephrology Institute of the Chinese People's Liberation Army, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Labor, Beijing, CN
| | - Jianhui Zhou
- Department of Nephrology, First Medical Center of Chinese PLA General Hospital, Nephrology Institute of the Chinese People's Liberation Army, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Labor, Beijing, CN
| | - Zhonggao Xu
- The First Hospital of Jilin University, Changchun, CN
| | - Zhaohui Ni
- Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, CN
| | - Yani He
- Daping Hospital, Army Medical University, Chongqing, CN
| | - Hongli Lin
- Key Laboratory of Kidney Disease, The Center for the Transformation Medicine of Kidney Disease, The First Affiliated Hospital of Dalian Medical University, Dalian, CN
| | - Gengru Jiang
- XinHua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, CN
| | - Xuefeng Sun
- Department of Nephrology, First Medical Center of Chinese PLA General Hospital, Nephrology Institute of the Chinese People's Liberation Army, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Labor, Beijing, CN
| | - Li Zhang
- Department of Nephrology, First Medical Center of Chinese PLA General Hospital, Nephrology Institute of the Chinese People's Liberation Army, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Labor, Beijing, CN
| | - Xiangmei Chen
- Department of Nephrology, First Medical Center of Chinese PLA General Hospital, Nephrology Institute of the Chinese People's Liberation Army, State Key Laboratory of Kidney Diseases, National Clinical Research Center for Kidney Diseases, Beijing Key Labor, Fuxing Road No.28, Beijing, CN
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Valvezan AJ, McNamara MC, Miller SK, Torrence ME, Asara JM, Henske EP, Manning BD. IMPDH inhibitors for antitumor therapy in tuberous sclerosis complex. JCI Insight 2020; 5:135071. [PMID: 32271165 PMCID: PMC7205253 DOI: 10.1172/jci.insight.135071] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/05/2020] [Indexed: 01/05/2023] Open
Abstract
Recent studies in distinct preclinical tumor models have established the nucleotide synthesis enzyme inosine-5'-monophosphate dehydrogenase (IMPDH) as a viable target for antitumor therapy. IMPDH inhibitors have been used clinically for decades as safe and effective immunosuppressants. However, the potential to repurpose these pharmacological agents for antitumor therapy requires further investigation, including direct comparisons of available compounds. Therefore, we tested structurally distinct IMPDH inhibitors in multiple cell and mouse tumor models of the genetic tumor syndrome tuberous sclerosis complex (TSC). TSC-associated tumors are driven by uncontrolled activation of the growth-promoting protein kinase complex mechanistic target of rapamycin (mTOR) complex 1 (mTORC1), which is also aberrantly activated in the majority of sporadic cancers. Despite eliciting similar immunosuppressive effects, the IMPDH inhibitor mizoribine, used clinically throughout Asia, demonstrated far superior antitumor activity compared with the FDA-approved IMPDH inhibitor mycophenolate mofetil (or CellCept, a prodrug of mycophenolic acid). When compared directly to the mTOR inhibitor rapamycin, mizoribine treatment provided a more durable antitumor response associated with tumor cell death. These results provide preclinical support for repurposing mizoribine, over other IMPDH inhibitors, as an alternative to mTOR inhibitors for the treatment of TSC-associated tumors and possibly other tumors featuring uncontrolled mTORC1 activity.
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Affiliation(s)
- Alexander J. Valvezan
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Molly C. McNamara
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Spencer K. Miller
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Margaret E. Torrence
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - John M. Asara
- Division of Signal Transduction, Beth Israel Deaconess Medical Center, and Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Elizabeth P. Henske
- Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Brendan D. Manning
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
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Anti-Tumor Potential of IMP Dehydrogenase Inhibitors: A Century-Long Story. Cancers (Basel) 2019; 11:cancers11091346. [PMID: 31514446 PMCID: PMC6770829 DOI: 10.3390/cancers11091346] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/01/2019] [Accepted: 09/02/2019] [Indexed: 01/15/2023] Open
Abstract
The purine nucleotides ATP and GTP are essential precursors to DNA and RNA synthesis and fundamental for energy metabolism. Although de novo purine nucleotide biosynthesis is increased in highly proliferating cells, such as malignant tumors, it is not clear if this is merely a secondary manifestation of increased cell proliferation. Suggestive of a direct causative effect includes evidence that, in some cancer types, the rate-limiting enzyme in de novo GTP biosynthesis, inosine monophosphate dehydrogenase (IMPDH), is upregulated and that the IMPDH inhibitor, mycophenolic acid (MPA), possesses anti-tumor activity. However, historically, enthusiasm for employing IMPDH inhibitors in cancer treatment has been mitigated by their adverse effects at high treatment doses and variable response. Recent advances in our understanding of the mechanistic role of IMPDH in tumorigenesis and cancer progression, as well as the development of IMPDH inhibitors with selective actions on GTP synthesis, have prompted a reappraisal of targeting this enzyme for anti-cancer treatment. In this review, we summarize the history of IMPDH inhibitors, the development of new inhibitors as anti-cancer drugs, and future directions and strategies to overcome existing challenges.
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Shi Y, Liu H, Chen XG, Shen ZY. Efficacy and Safety of Mizoribine Combined With Tacrolimus in Living Donor Kidney Transplant Recipients: 3-Year Results by a Chinese Single Center Study. Transplant Proc 2019; 51:1337-1342. [PMID: 31155174 DOI: 10.1016/j.transproceed.2019.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/20/2019] [Accepted: 03/04/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Mizoribine (MZR) was effective and safe for living Chinese donor kidney transplantation (LDKT) on tacrolimus-based treatment 1 year after transplantation. We investigated whether MZR was effective and safe for LDKT on tacrolimus-based treatment with long follow-up periods. METHODS We compared 22 LDKT recipients who were administered MZR, tacrolimus, and corticosteroids with a control group (n = 20) treated with mycophenolate mofetil (MMF), tacrolimus, and corticosteroids. Primary efficacy endpoints were 3-year patient survival, 3-year graft survival, and acute rejection (AR) rate within 3 years after transplantation. RESULTS The 3-year patient and graft survival rates for the MZR and MMF groups were 100%. The AR rate after transplantation was 18.2% for the MZR group and 10.0% for the MMF group; the difference was not significant (P = .665). There was no significant difference in serum creatinine levels, glomerular filtration rates (eGFR), serum urate levels, blood urea nitrogen, and cystatin C levels 12, 24, and 36 months after transplantation. No significant differences in the CD3, CD4, CD8, CD4/CD8, and CD45 were observed between the 2 groups 12, 24, and 36 months after transplantation. There were no significant differences in adverse events among the MZR or the MMF group, whereas the prevalence of gastrointestinal symptoms were significantly lower in the MZR treatment group (P = .003), especially acid reflux (P = .007). Compared with the MMF group, the MZR group should lighten the burden on patients. CONCLUSION MZR with tacrolimus and corticosteroids provides satisfactory immunosuppression and higher safety for Chinese LDKT over a 3-year follow-up.
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Affiliation(s)
- Yi Shi
- Department of Urology, Beijing Tsinghua Changgung Hospital, Beijing, China; Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China.
| | - Hang Liu
- Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China
| | - Xin-Guo Chen
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
| | - Zhong-Yang Shen
- Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China; Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
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Shi Y, Liu H, Chen XG, Shen ZY. Hyperuricemia in Living Donor Kidney Transplantation Patients During Mizoribine Administration Caused Mainly by Changes in Kidney Function. Transplant Proc 2019; 51:1392-1396. [PMID: 31155176 DOI: 10.1016/j.transproceed.2019.01.133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 01/28/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND Although mizoribine (MZR) is used as an immunosuppressant after renal transplantation, the occurrence of hyperuricemia has been reported. The onset of hyperuricemia is often observed within the first several months after surgery. Since MZR is a renal excretion-type drug excreted as an unchanged drug from the kidneys, MZR blood concentrations may rise due to the influence of renal function. We investigated whether the onset of hyperuricemia after MZR administration was associated with the direct effect of a change in renal function. METHODS Serum uric acid (serum UA), serum creatinine (sCr), serum β2-microglobulin (serum β2-MG), and serum cystatin C (serum Cys-C) were measured for about 3 months in 22 subjects. Correlation coefficients were calculated using the change rates of serum UA and sCr (Δ serum UA, Δ sCr), serum UA and serum β2-MG (Δ serum UA, Δ serum β2-MG), and serum UA and serum Cys-C (Δ serum UA, Δ serum Cys-C) at the onset of hyperuricemia. RESULTS The correlation coefficients between Δ serum UA and Δ sCr, Δ serum UA and Δ serum β2-MG, and Δ serum UA and Δ serum Cys-C were 0.723 (P < .001), 0.863 (P < .001) and 0.548 (P < .001), respectively. Further, serum UA and sCr level reached their highest peak on the same day after MZR administration, and the behavior was mostly consistent. CONCLUSION It was suggested that hyperuricemia occurred about 3 months after MZR administration due mainly to temporary changes in kidney function.
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Affiliation(s)
- Yi Shi
- Department of Urology, Beijing Tsinghua Changgung Hospital, Beijing, China; Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China.
| | - Hang Liu
- Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China
| | - Xin-Guo Chen
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
| | - Zhong-Yang Shen
- Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China; Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
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8
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Xia ZK, Gao YF, Rong LP, Dang XQ, Shen Q, Jiang XY, Yi ZW, Xu H. Usefulness of mizoribine administration in children with frequently relapsing nephrotic syndrome, and the relationship between pharmacokinetic parameters and efficacy: a multicenter prospective cohort study in China. World J Pediatr 2019; 15:262-269. [PMID: 30864060 DOI: 10.1007/s12519-019-00241-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/14/2018] [Indexed: 11/28/2022]
Abstract
BACKGROUND Mizoribine (MZR) is an immunosuppressant used to treat adult nephropathy. There is little experience with the drug in treating Chinese children with frequently relapsing nephrotic syndrome (FRNS). We investigated the efficacy and safety for treating MZR with FRNS. Furthermore, the relationship between efficacy and serum concentration was investigated. METHODS A prospective multicenter observational 12-month study was performed for evaluating the usefulness of MZR with FRNS. Serum MZR concentration was measured, and the relationships between pharmacokinetic parameters (Cmax, AUC), number of relapses, and urinary protein were evaluated. RESULTS Eighty-two pediatric patients from four hospitals were treated with MZR and prednisone. MZR treatment significantly reduced the number of relapses and steroid doses. A correlation between pharmacokinetic parameters and relapses was observed, which fits well with the sigmoidal Emax model. Even in the relationship between pharmacokinetic parameters and urinary proteins, it was recognized that there was a threshold in the pharmacokinetic parameters for the therapeutic effect similar to the results obtained with the sigmoidal Emax model. Eleven patients (13.4%) experienced mild adverse events. CONCLUSIONS MZR therapy was effective in reducing the number of relapses and steroid doses. No severe adverse reactions were observed. Therapeutically effective serum concentrations were estimated to be Cmax ≥ about 2 μg/mL or AUC ≥ about 10 μg h/mL. MZR and steroid treatment were effective and safe for pediatric FRNS.
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Affiliation(s)
- Zheng-Kun Xia
- Department of Pediatrics, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China.
| | - Yuan-Fu Gao
- Department of Pediatrics, Jinling Hospital, Nanjing University School of Medicine, Nanjing 210002, China
| | - Li-Ping Rong
- Department of Pediatrics, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China
| | - Xi-Qiang Dang
- Department of Pediatric Nephrology, Children's Medical Center, Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Qian Shen
- Department of Nephrology and Rheumatology, Children's Hospital of Fudan University, Shanghai 201102, China
| | - Xiao-Yun Jiang
- Department of Pediatrics, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou 510080, China
| | - Zhu-Wen Yi
- Department of Pediatric Nephrology, Children's Medical Center, Second Xiangya Hospital, Central South University, Changsha 410011, China
| | - Hong Xu
- Department of Nephrology and Rheumatology, Children's Hospital of Fudan University, Shanghai 201102, China
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9
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Population Pharmacokinetic Analysis of Mizoribine in Chinese Renal Transplant Recipients. Transplant Proc 2018; 50:2392-2397. [PMID: 30316364 DOI: 10.1016/j.transproceed.2018.03.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 03/06/2018] [Indexed: 11/24/2022]
Abstract
BACKGROUND We calculated the population pharmacokinetics of mizoribine in adult Chinese patients and compared the parameters with those of Japanese patients to determine whether there are any ethnic differences in blood concentration transition between these 2 populations. METHODS The blood concentrations of mizoribine in 21 Chinese patients who were administered mizoribine after renal transplantation were measured at 304 time points. The absorption lag time, absorption rate constant, apparent distribution volume, and oral clearance were thereafter calculated and compared with the respective Japanese references. RESULTS The absorption lag time, absorption rate constant, and apparent distribution volume calculated in this study were, respectively, 0.353 hour, 0.856 hour-1, and 0.776 L/kg. The oral clearance was calculated as 2.18 times the creatinine clearance using creatinine clearance as a function. The absorption rate constant, apparent distribution volume, and oral clearance are determinants of the maximum blood concentration, trough, and area under the blood concentration time curve. The relative absorption rate constant, apparent distribution volume, and oral clearance were 0.9-, 0.9-, and 1.2-fold, respectively, in Chinese patients compared with those in Japanese patients. These values are within the confidence limit, suggesting that there is no significant PK difference between the 2 ethnic groups. CONCLUSIONS Results of this study showed no ethnic difference in blood mizoribine concentration transition between Chinese and Japanese patients. In addition, the population pharmacokinetic parameters obtained in this study are useful in determining the initial dosage or in the Bayesian analysis of mizoribine concentrations using scarce time points.
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Valvezan AJ, Turner M, Belaid A, Lam HC, Miller SK, McNamara MC, Baglini C, Housden BE, Perrimon N, Kwiatkowski DJ, Asara JM, Henske EP, Manning BD. mTORC1 Couples Nucleotide Synthesis to Nucleotide Demand Resulting in a Targetable Metabolic Vulnerability. Cancer Cell 2017; 32:624-638.e5. [PMID: 29056426 PMCID: PMC5687294 DOI: 10.1016/j.ccell.2017.09.013] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/21/2017] [Accepted: 09/20/2017] [Indexed: 12/13/2022]
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) supports proliferation through parallel induction of key anabolic processes, including protein, lipid, and nucleotide synthesis. We hypothesized that these processes are coupled to maintain anabolic balance in cells with mTORC1 activation, a common event in human cancers. Loss of the tuberous sclerosis complex (TSC) tumor suppressors results in activation of mTORC1 and development of the tumor syndrome TSC. We find that pharmacological inhibitors of guanylate nucleotide synthesis have selective deleterious effects on TSC-deficient cells, including in mouse tumor models. This effect stems from replication stress and DNA damage caused by mTORC1-driven rRNA synthesis, which renders nucleotide pools limiting. These findings reveal a metabolic vulnerability downstream of mTORC1 triggered by anabolic imbalance.
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Affiliation(s)
- Alexander J Valvezan
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Marc Turner
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Amine Belaid
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Hilaire C Lam
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Spencer K Miller
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Molly C McNamara
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Christian Baglini
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | | | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Boston, MA, USA; Howard Hughes Medical Institute, Boston, MA, USA
| | - David J Kwiatkowski
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - John M Asara
- Division of Signal Transduction, Beth Israel Deaconess Medical Center, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Elizabeth P Henske
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Brendan D Manning
- Department of Genetics and Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
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Nayar U, Sadek J, Reichel J, Hernandez-Hopkins D, Akar G, Barelli PJ, Sahai MA, Zhou H, Totonchy J, Jayabalan D, Niesvizky R, Guasparri I, Hassane D, Liu Y, Sei S, Shoemaker RH, Warren JD, Elemento O, Kaye KM, Cesarman E. Identification of a nucleoside analog active against adenosine kinase-expressing plasma cell malignancies. J Clin Invest 2017; 127:2066-2080. [PMID: 28504647 PMCID: PMC5451239 DOI: 10.1172/jci83936] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 03/16/2017] [Indexed: 12/22/2022] Open
Abstract
Primary effusion lymphoma (PEL) is a largely incurable malignancy of B cell origin with plasmacytic differentiation. Here, we report the identification of a highly effective inhibitor of PEL. This compound, 6-ethylthioinosine (6-ETI), is a nucleoside analog with toxicity to PEL in vitro and in vivo, but not to other lymphoma cell lines tested. We developed and performed resistome analysis, an unbiased approach based on RNA sequencing of resistant subclones, to discover the molecular mechanisms of sensitivity. We found different adenosine kinase-inactivating (ADK-inactivating) alterations in all resistant clones and determined that ADK is required to phosphorylate and activate 6-ETI. Further, we observed that 6-ETI induces ATP depletion and cell death accompanied by S phase arrest and DNA damage only in ADK-expressing cells. Immunohistochemistry for ADK served as a biomarker approach to identify 6-ETI-sensitive tumors, which we documented for other lymphoid malignancies with plasmacytic features. Notably, multiple myeloma (MM) expresses high levels of ADK, and 6-ETI was toxic to MM cell lines and primary specimens and had a robust antitumor effect in a disseminated MM mouse model. Several nucleoside analogs are effective in treating leukemias and T cell lymphomas, and 6-ETI may fill this niche for the treatment of PEL, plasmablastic lymphoma, MM, and other ADK-expressing cancers.
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Affiliation(s)
| | | | | | | | - Gunkut Akar
- Department of Pathology and Laboratory Medicine
| | | | - Michelle A. Sahai
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, USA
| | - Hufeng Zhou
- Department of Medicine, Brigham and Women’s Hospital, and Harvard Medical School, Boston, Massachusetts, USA
| | | | | | - Ruben Niesvizky
- Division of Hematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | | | - Duane Hassane
- Division of Hematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Yifang Liu
- Department of Pathology and Laboratory Medicine
| | - Shizuko Sei
- Viral Vector Toxicology Section, Laboratory of Human Toxicology and Pharmacology, SAIC-Frederick, National Cancer Institute at Frederick, Frederick, Maryland, USA
| | - Robert H. Shoemaker
- Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, Frederick, Maryland, USA
| | | | - Olivier Elemento
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York, New York, USA
| | - Kenneth M. Kaye
- Department of Medicine, Brigham and Women’s Hospital, and Harvard Medical School, Boston, Massachusetts, USA
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Shi Y, Liu H, Chen XG, Shen ZY. Comparison of Mizoribine and Mycophenolate Mofetil With a Tacrolimus-Based Immunosuppressive Regimen in Living-Donor Kidney Transplantation Recipients: A Retrospective Study in China. Transplant Proc 2017; 49:26-31. [PMID: 28104150 DOI: 10.1016/j.transproceed.2016.10.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND A retrospective study was conducted to investigate the prevalence of gastrointestinal (GI) symptoms as well as the efficacy and safety of mizoribine (MZR) and mycophenolate mofetil (MMF) in Chinese living-donor kidney transplantation (LDKT). METHODS Forty-two recipients enrolled between January 2012 and March 2014 were treated with either MZR (n = 22) or MMF (n = 20). All patients were treated in combination with a tacrolimus-based immunosuppressive regimen, besides the study drugs. RESULTS GI symptoms were observed in 1 of 22 patients (4.5%) and 10 of 20 patients (50%) in MZR treatment group and MMF treatment group, respectively (P = .001), during the post-transplantation 1 year. No significant differences in the incidence of acid reflux, bloated stomach feeling, and constipation were observed between the two groups. No recipient developed diarrhea in the MZR treatment group, whereas 30% of the MMF treatment group developed diarrhea (P = .007). The averages of GI symptom severity total score and diarrhea score were significantly lower in the MZR treatment group compare with MMF treatment group. There were no inter-group differences in background characteristics. There were no significant differences in acute rejection rate and clinical findings between these two groups, whereas the prevalence of cytomegalovirus infection and leukopenia were significantly lower in the MZR treatment group. There was no significant difference on adverse events such as hyperuricemia or other adverse events. CONCLUSIONS This study demonstrated a significantly lower incidence of GI symptoms for treatment with MZR compared with MMF and good efficacy and safety in Chinese LDKT with MZR.
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Affiliation(s)
- Y Shi
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China; Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China.
| | - H Liu
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
| | - X-G Chen
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China
| | - Z-Y Shen
- Institute of Liver Transplantation, General Hospital of Chinese People's Armed Police Force, Beijing, China; Organ Transplantation Center, Tianjin First Center Hospital, Tianjin, China
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Nagai T, Uemura O, Kaneda H, Ushijima K, Ohta K, Gotoh Y, Satomura K, Shimizu M, Fujieda M, Morooka M, Yamada T, Yamada M, Wada N, Hashimoto Y. The true distribution volume and bioavailability of mizoribine in children with chronic kidney disease. Clin Exp Nephrol 2016; 21:884-888. [PMID: 27873037 DOI: 10.1007/s10157-016-1353-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 10/21/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Mizoribine (MZR) is used kidney transplant and various kidney diseases. However, few studies reported the association between pharmacokinetics and pharmacodynamics. The Pharmacokinetics Study Group for Pediatric Kidney Disease (PSPKD) used population pharmacokinetics (PPK) analysis and Bayesian analysis to investigate the usefulness of MZR. In this study, the fact that almost all MZR are excreted unchanged in urine was used to calculate its bioavailability (F) and true distribution volume (V d), and analyzed these correlation with age. METHODS Ishida et al. reported a PPK analysis by the PSPKD. In the present study, 71 samples extracted from their study population of 105 pediatric chronic kidney disease patients aged between 1 and 20 years were investigated. The bioavailability was calculated by measuring total excreted MZR in 24 h urine samples, and this was compared to the oral dosage. The apparent distribution volume (V d/F) obtained from Bayesian analysis was then used to calculate true distribution volume (V d), and the correlation of each parameter with age was investigated. RESULTS The median dose of MZR per weight was 5.17 mg/kg/day. Median bioavailability was 32.02%. Median V d per weight was 0.46 L/kg. There was a significant, weakly positive correlation between bioavailability and age (p = 0.026). There was also a significant, weakly negative correlation between V d per weight and age (p = 0.003). CONCLUSION Bioavailability and V d per weight tended to decrease depending on age. The younger patient required larger dose required to obtain the maximum effect from MZR, and this is important for immunosuppressive therapy.
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Affiliation(s)
- Takuhito Nagai
- Division of Pediatric Nephrology, Department of Kidney Center, Aichi Medical University, 1-1, Nagakute City, Aichi, 480-1195, Japan.
| | - Osamu Uemura
- Department of Pediatric Nephrology, Aichi Children's Health and Medical Center, Obu, Aichi, Japan
| | - Hisashi Kaneda
- Department of Pediatrics, Toyama City Hospital, Toyama, Japan
| | | | - Kazuhide Ohta
- Department of Pediatrics, Kanazawa Medical Center, Kanazawa, Japan
| | - Yoshimitsu Gotoh
- Kidney Center Pediatrics, Nagoya Daini Red Cross Hospital, Nagoya, Aichi, Japan
| | - Kenichi Satomura
- Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan
| | - Masaki Shimizu
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Mikiya Fujieda
- Department of Pediatrics, Kochi Medical School, Kochi University, Kochi, Japan
| | - Masashi Morooka
- Department of Pediatrics, Fujita Health University, Toyoake, Aichi, Japan
| | - Takuji Yamada
- Department of Pediatrics, Nagoya City West Medical Center, Aichi, Japan
| | - Masayoshi Yamada
- Department of Pediatric Nephrology, Shizuoka Children's Hospital, Shizuoka, Japan
| | - Naohiro Wada
- Department of Pediatric Nephrology, Shizuoka Children's Hospital, Shizuoka, Japan
| | - Yukiya Hashimoto
- Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
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Saito T, Iwano M, Matsumoto K, Mitarai T, Yokoyama H, Yorioka N, Nishi S, Yoshimura A, Sato H, Ogahara S, Sasatomi Y, Kataoka Y, Ueda S, Koyama A, Maruyama S, Nangaku M, Imai E, Matsuo S, Tomino Y. Mizoribine therapy combined with steroids and mizoribine blood concentration monitoring for idiopathic membranous nephropathy with steroid-resistant nephrotic syndrome. Clin Exp Nephrol 2016; 21:961-970. [PMID: 27783276 PMCID: PMC5698362 DOI: 10.1007/s10157-016-1340-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/04/2016] [Indexed: 11/26/2022]
Abstract
Background We designed a prospective and randomized trial of mizoribine (MZR) therapy combined with prednisolone (PSL) for idiopathic membranous nephropathy (IMN) with steroid-resistant nephrotic syndrome (SRNS). Methods Patients with IMN were divided into 2 groups, and MZR combined with PSL was administered for 2 years. PSL was initially prescribed at 40 mg/day and tapered. MZR was given once-a-day at 150 mg and 3-times-a-day at 50 mg each to groups 1 and 2. Serum MZR concentrations from 0 to 4 h after administration were examined within one month of treatment. The concentration curve and peak serum level (Cmax) of MZR were estimated by the population pharmacokinetic (PPK) parameters of MZR. Results At 2 years, 10 of 19 patients (52.6 %) in group 1 and 7 of 18 patients (38.9 %) in group 2 achieved complete remission (CR). The time-to-remission curve using the Kaplan–Meier technique revealed an increase in the cumulative CR rate in group 1, but no significant difference between the groups. Meanwhile, there was a significant difference in Cmax between groups 1 and 2 (mean ± SD: 1.20 ± 0.52 vs. 0.76 ± 0.39 μg/mL, p = 0.04), and Cmax levels in CR cases were significantly higher than those in non-CR cases. Receiver operating characteristic analysis showed that Cmax more than 1.1 µg/mL was necessary for CR in once-a-day administration. Conclusion Administration of MZR once a day is useful when combined with PSL for treatment of IMN with SRNS. In addition, it is important to assay the serum concentration of MZR and to determine Cmax, and more than 1.1 µg/mL of Cmax is necessary for CR.
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Affiliation(s)
- Takao Saito
- Professor Emeritus, Fukuoka University, and Sanko Clinic, 4-9-3 Ropponmatsu, Chuo-ku, Fukuoka, 810-0044, Japan.
| | - Masayuki Iwano
- Division of Nephrology, Department of General Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Koichi Matsumoto
- The University Research Center, General Science Institute, School of Medicine, Nihon University, Tokyo, Japan
| | - Tetsuya Mitarai
- Department of Nephrology and Blood Purification, Saitama Medical Center, Saitama Medical University, Kawagoe, Japan
| | - Hitoshi Yokoyama
- Division of Nephrology, Kanazawa Medical University School of Medicine, Ishikawa, Japan
| | | | - Shinichi Nishi
- Division of Nephrology and Kidney Center, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Ashio Yoshimura
- Division of Nephrology, Department of Internal Medicine, Showa University Fujigaoka Hospital, Yokohama, Japan
| | - Hiroshi Sato
- Division of Nephrology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Satoru Ogahara
- Division of Nephrology and Rheumatology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Yoshie Sasatomi
- Division of Nephrology and Rheumatology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Yasufumi Kataoka
- Department of Pharmaceutical Care and Health Sciences, Faculty of Pharmaceutical Sciences, Fukuoka University, Fukuoka, Japan
| | | | - Akio Koyama
- Professor Emeritus, Tsukuba University, Ibaraki, Japan
| | - Shoichi Maruyama
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masaomi Nangaku
- Division of Nephrology and Endocrinology, University of Tokyo School of Medicine, Tokyo, Japan
| | - Enyu Imai
- Nakayamadera Imai Clinic, Hyogo, Japan
| | - Seiichi Matsuo
- Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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Yan TZ, Wu XQ, Rong L. A four-drug combination therapy consisting of low-dose tacrolimus, low-dose mycophenolate mofetil, corticosteroids, and mizoribine in living donor renal transplantation: A randomized study. SAGE Open Med 2016; 4:2050312116643672. [PMID: 27231549 PMCID: PMC4871204 DOI: 10.1177/2050312116643672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/15/2016] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVE We compared a three-drug combination therapy (control group) consisting of tacrolimus, mycophenolate mofetil, and corticosteroids in living donor renal transplantation with a four-drug combination therapy (study group), in which the doses of tacrolimus and mycophenolate mofetil were halved and the immunosuppressive drug mizoribine was added, in order to determine whether the incidence rates of acute rejection after transplantation between the study group and the control group are similar, whether the study group regimen prevents the occurrence of calcineurin inhibitor-induced renal damage, and whether the study group regimen prevents adverse effects such as diarrhea caused by mycophenolate mofetil. METHODS We investigated the incidence of acute rejection, serum creatinine levels, and estimated glomerular filtration rate and the incidence of adverse effects such as diarrhea. RESULTS There was no significant difference between the two groups in the incidence of acute rejection. Renal function (estimated glomerular filtration rate and serum creatinine) was maintained in the control group whereas in the study group renal function gradually improved, with a statistical difference observed at 12 months. The incidence of gastrointestinal symptoms including diarrhea was significantly higher in the control group than in the study group. There was no significant difference in the incidence of cytomegalovirus infection and other adverse effects. CONCLUSION These results suggest the study group therapy is an effective regimen in preventing acute rejection and the deterioration of renal function. These results also show this therapy can reduce the incidence of adverse effects such as gastrointestinal symptoms.
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Affiliation(s)
- Tian-Zhong Yan
- Department of Urology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Xiao-Qiang Wu
- Department of Urology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Lu Rong
- Department of Urology, Henan Provincial People's Hospital, Zhengzhou, China
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16
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Izumi Y, Nakaoka K, Kamata M, Iwanaga N, Imadachi S, Kurohama H, Ito M, Migita K. Steroid-resistant protein-losing gastroenteropathy complicated with Sjögren's syndrome successfully treated with mizoribine. Mod Rheumatol 2016; 28:716-720. [PMID: 26872871 DOI: 10.3109/14397595.2016.1145570] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A 64-year-old woman with leg edema was diagnosed with protein-losing gastroenteropathy and Sjögren's syndrome. Central venous nutrition led to infection of her catheter, ascites, and deep vein thrombosis. Following successful treatment of these conditions with antibiotics and anticoagulants, she was treated unsuccessfully with prednisolone and steroid pulse therapy. Mizoribine add-on markedly reduced edema and normalized serum albumin. This is the first report of a steroid-resistant protein-losing gastroenteropathy patient with Sjögren's syndrome successfully treated with mizoribine.
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Affiliation(s)
- Yasumori Izumi
- a Department of Rheumatology.,b General Internal Medicine , and
| | - Kenjiro Nakaoka
- a Department of Rheumatology.,b General Internal Medicine , and
| | | | | | | | | | - Masahiro Ito
- c Pathology , NHO Nagasaki Medical Center , Omura , Japan
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Tanaka E, Inoue E, Kawaguchi Y, Tomatsu T, Yamanaka H, Hara M, Kamatani N. Acceptability and usefulness of mizoribine in the management of rheumatoid arthritis in methotrexate-refractory patients and elderly patients, based on analysis of data from a large-scale observational cohort study. Mod Rheumatol 2014. [DOI: 10.3109/s10165-006-0487-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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18
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Horikoshi M, Ito S, Ishikawa M, Umeda N, Kondo Y, Tsuboi H, Hayashi T, Goto D, Matsumoto I, Sumida T. Efficacy of mizoribine pulse therapy in patients with rheumatoid arthritis who show a reduced or insufficient response to infliximab. Mod Rheumatol 2014. [DOI: 10.3109/s10165-009-0162-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Bidirectional communication between oocytes and ovarian follicular somatic cells is required for meiotic arrest of mammalian oocytes. Proc Natl Acad Sci U S A 2013; 110:E3723-9. [PMID: 23980176 DOI: 10.1073/pnas.1314829110] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Coordinated regulation of oocyte and ovarian follicular development is essential for fertility. In particular, the progression of meiosis, a germ cell-specific cell division that reduces the number of chromosomes from diploid to haploid, must be arrested until just before ovulation. Follicular somatic cells are well-known to impose this arrest, which is essential for oocyte-follicle developmental synchrony. Follicular somatic cells sustain meiotic arrest via the natriuretic peptide C/natriuretic peptide receptor 2 (NPPC/NPR2) system, and possibly also via high levels of the purine hypoxanthine in the follicular fluid. Upon activation by the ligand NPPC, NPR2, the predominant guanylyl cyclase in follicular somatic cells, produces cyclic guanosine monophosphate (cGMP), which maintains meiotic arrest after transfer to the oocyte via gap junctions. Here we report that both the NPPC/NPR2 system and hypoxanthine require the activity of inosine monophosphate dehydrogenase (IMPDH), the rate-limiting enzyme required for the production of guanylyl metabolites and cGMP. Furthermore, oocyte-derived paracrine factors, particularly the growth differentiation factor 9-bone morphogenetic protein 15 heterodimer, promote expression of Impdh and Npr2 and elevate cGMP levels in cumulus cells. Thus, although the somatic compartment of ovarian follicles plays an essential role in the maintenance of oocyte meiotic arrest, as has been known for many years, this function of the somatic cells is surprisingly regulated by signals from the oocyte itself.
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Picard-Jean F, Bougie I, Shuto S, Bisaillon M. The immunosuppressive agent mizoribine monophosphate is an inhibitor of the human RNA capping enzyme. PLoS One 2013; 8:e54621. [PMID: 23349942 PMCID: PMC3547949 DOI: 10.1371/journal.pone.0054621] [Citation(s) in RCA: 6] [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: 08/07/2012] [Accepted: 12/13/2012] [Indexed: 11/18/2022] Open
Abstract
Mizoribine monophosphate (MZP) is a specific inhibitor of the cellular inosine-5′-monophosphate dehydrogenase (IMPDH), the enzyme catalyzing the rate-limiting step of de novo guanine nucleotide biosynthesis. MZP is a highly potent antagonistic inhibitor of IMPDH that blocks the proliferation of T and B lymphocytes that use the de novo pathway of guanine nucleotide synthesis almost exclusively. In the present study, we investigated the ability of MZP to directly inhibit the human RNA capping enzyme (HCE), a protein harboring both RNA 5′-triphosphatase and RNA guanylyltransferase activities. HCE is involved in the synthesis of the cap structure found at the 5′ end of eukaryotic mRNAs, which is critical for the splicing of the cap-proximal intron, the transport of mRNAs from the nucleus to the cytoplasm, and for both the stability and translation of mRNAs. Our biochemical studies provide the first insight that MZP can inhibit the formation of the RNA cap structure catalyzed by HCE. In the presence of MZP, the RNA 5′-triphosphatase activity appears to be relatively unaffected while the RNA guanylyltransferase activity is inhibited, indicating that the RNA guanylyltransferase activity is the main target of MZP inhibition. Kinetic studies reveal that MZP is a non-competitive inhibitor that likely targets an allosteric site on HCE. Mizoribine also impairs mRNA capping in living cells, which could account for the global mechanism of action of this therapeutic agent. Together, our study clearly demonstrates that mizoribine monophosphate inhibits the human RNA guanylyltransferase in vitro and impair mRNA capping in cellulo.
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Affiliation(s)
- Frédéric Picard-Jean
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Isabelle Bougie
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Satoshi Shuto
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Martin Bisaillon
- Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
- * E-mail:
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Involvement of Multiple Transporters-mediated Transports in Mizoribine and Methotrexate Pharmacokinetics. Pharmaceuticals (Basel) 2012; 5:802-36. [PMID: 24280676 PMCID: PMC3763673 DOI: 10.3390/ph5080802] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 07/25/2012] [Accepted: 08/07/2012] [Indexed: 12/19/2022] Open
Abstract
Mizoribine is administered orally and excreted into urine without being metabolized. Many research groups have reported a linear relationship between the dose and peak serum concentration, between the dose and AUC, and between AUC and cumulative urinary excretion of mizoribine. In contrast, a significant interindividual variability, with a small intraindividual variability, in oral bioavailability of mizoribine is also reported. The interindividual variability is mostly considered to be due to the polymophisms of transporter genes. Methotrexate (MTX) is administered orally and/or by parenteral routes, depending on the dose. Metabolic enzymes and multiple transporters are involved in the pharmacokinetics of MTX. The oral bioavailability of MTX exhibits a marked interindividual variability and saturation with increase in the dose of MTX, with a small intraindividual variability, where the contribution of gene polymophisms of transporters and enzymes is suggested. Therapeutic drug monitoring of both mizoribine and MTX is expected to improve their clinical efficacy in the treatment of rheumatoid arthritis.
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Yasutake Y, Ota H, Hino E, Sakasegawa SI, Tamura T. Structures of Burkholderia thailandensis nucleoside kinase: implications for the catalytic mechanism and nucleoside selectivity. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2011; 67:945-56. [PMID: 22101821 DOI: 10.1107/s0907444911038777] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 09/21/2011] [Indexed: 11/10/2022]
Abstract
The nucleoside kinase (NK) from the mesophilic Gram-negative bacterium Burkholderia thailandensis (BthNK) is a member of the phosphofructokinase B (Pfk-B) family and catalyzes the Mg(2+)- and ATP-dependent phosphorylation of a broad range of nucleosides such as inosine (INO), adenosine (ADO) and mizoribine (MZR). BthNK is currently used in clinical practice to measure serum MZR levels. Here, crystal structures of BthNK in a ligand-free form and in complexes with INO, INO-ADP, MZR-ADP and AMP-Mg(2+)-AMP are described. The typical homodimeric architecture of Pfk-B enzymes was detected in three distinct conformational states: an asymmetric dimer with one subunit in an open conformation and the other in a closed conformation (the ligand-free form), a closed conformation (the binary complex with INO) and a fully closed conformation (the other ternary and quaternary complexes). The previously unreported fully closed structures suggest the possibility that Mg(2+) might directly interact with the β- and γ-phosphates of ATP to maintain neutralization of the negative charge throughout the reaction. The nucleoside-complex structures also showed that the base moiety of the bound nucleoside is partly exposed to the solvent, thereby enabling the recognition of a wide range of nucleoside bases. Gly170 is responsible for the solvent accessibility of the base moiety and is assumed to be a key residue for the broad nucleoside recognition of BthNK. Remarkably, the G170Q mutation increases the specificity of BthNK for ADO. These findings provide insight into the conformational dynamics, catalytic mechanism and nucleoside selectivity of BthNK and related enzymes.
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Affiliation(s)
- Yoshiaki Yasutake
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Sapporo 062-8517, Japan
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Takahashi K, Oharaseki T, Nagao T, Yokouchi Y, Yamada H, Nagi-Miura N, Ohno N, Saji T, Okazaki T, Suzuki K. Mizoribine provides effective treatment of sequential histological change of arteritis and reduction of inflammatory cytokines and chemokines in an animal model of Kawasaki disease. Pediatr Rheumatol Online J 2011; 9:30. [PMID: 21958311 PMCID: PMC3239324 DOI: 10.1186/1546-0096-9-30] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Accepted: 09/29/2011] [Indexed: 11/10/2022] Open
Abstract
UNLABELLED The incidence of panvasculitis in the coronary arteries and aortic root was 100% in the control group. The incidence of panvasculitis in the MZR group decreased to 50%. Moreover, the scope and severity of the inflammation of those sites were significantly reduced in the MZR group as well as the IgG group. On the other hand, increased cytokines and chemokines, such as IL-1α, TNF-α, KC, MIP-1α, GM-CSF, and IL-13, in the nontreatment group were significantly suppressed by treatment with MZR, but the MCP-1 level increased. In addition, IL-1α, TNF-α, IL-10, IL-13, and MIP-1α were suppressed by treatment in the IgG group. BACKGROUND Intravenous immunoglobulin (IVIg) treatment results in an effective response from patients with acute-phase Kawasaki disease (KD), but 16.5% of them remain nonresponsive to IVIg. To address this therapeutic challenge, we tried a new therapeutic drug, mizoribine (MZR), in a mouse model of KD, which we have established using injections of Candida albicans water-soluble fractions (CAWS). METHODS CAWS (4 mg/mouse) were injected intraperitoneally into C57BL/6N mice for 5 consecutive days. MZR or IgG was administered for 5 days. After 4 weeks, the mice were sacrificed and autopsied, the hearts were fixed in 10% neutral formalin, and plasma was taken to measure cytokines and chemokines using the Bio-Plex system. RESULTS The incidence of panvasculitis in the coronary arteries and aortic root was 100% in the control group. The incidence of panvasculitis in the MZR group decreased to 50%. Moreover, the scope and severity of the inflammation of those sites were significantly reduced in the MZR group as well as the IgG group. On the other hand, increased cytokines and chemokines, such as IL-1α TNF-α, KC, MIP-1α, GM-CSF, and IL-13, in the nontreatment group were significantly suppressed by treatment with MZR, but the MCP-1 level increased. In addition, IL-1α, TNF-α, IL-10, IL-13, and MIP-1α were suppressed by treatment in the IgG group. CONCLUSION MZR treatment suppressed not only the incidence, range, and degree of vasculitis, but also inflammatory cytokines and chemokines in the plasma of the KD vasculitis model mice, suggesting that MZR may be useful for treatment of KD.
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Affiliation(s)
- Kei Takahashi
- Inflammation Program, Dept, of Immunology, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, 260-8670, Japan.
| | - Toshiaki Oharaseki
- Department of Pathology, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, 153-8515, Japan
| | - Tomokazu Nagao
- Inflammation Program, Dept. of Immunology, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, 260-8670, Japan
| | - Yuki Yokouchi
- Department of Pathology, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, 153-8515, Japan
| | - Hitomi Yamada
- Department of Pathology, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, 153-8515, Japan
| | - Noriko Nagi-Miura
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan
| | - Naohito Ohno
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan
| | - Tsutomu Saji
- Department of Pediatrics, Toho University Omori Medical Center, Ota-ku, Tokyo, 143-8541, Japan
| | - Tomio Okazaki
- Kure Kyosai Hospital, Kure, Hiroshima, 737-8505, Japan
| | - Kazuo Suzuki
- Inflammation Program, Dept. of Immunology, Chiba University Graduate School of Medicine, Chuo-ku, Chiba, 260-8670, Japan
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Kuramoto T, Daikoku T, Yoshida Y, Takemoto M, Oshima K, Eizuru Y, Kanda Y, Miyawaki T, Shiraki K. Novel anticytomegalovirus activity of immunosuppressant mizoribine and its synergism with ganciclovir. J Pharmacol Exp Ther 2010; 333:816-21. [PMID: 20194528 DOI: 10.1124/jpet.109.160630] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cytomegalovirus (CMV) infection is a prominent infection in transplant recipients. The immunosuppressive drug mizoribine was shown to have anti-CMV activity in vitro and was reported to have an anti-CMV effect in renal transplantation. This study characterized the anti-CMV activity of mizoribine in vitro and its synergistic activity with ganciclovir. Mizoribine suppressed replication and at the EC(50) for plaque inhibition of 12.0 microg/ml. Mizoribine and ganciclovir exerted a strong synergism in anti-CMV activity. Mizoribine depletes guanosine nucleotides by inhibiting inosine monophosphate dehydrogenase and may increase the ratio of ganciclovir to guanosine in treated cells, resulting in a strong synergistic augmentation of the anti-CMV activity of ganciclovir. Two clinical isolates with UL97 mutations were less susceptible to mizoribine than the Towne strain but were equally susceptible in the presence of guanine. Two mizoribine-resistant strains were isolated after culture for 3 months with 100 microg/ml mizoribine, but they were as sensitive to ganciclovir as the parent Towne strain. The anti-CMV activity of mizoribine was antagonized by 2'-deoxyguanosine. Mizoribine inhibited CMV replication directly, and the sequence of mizoribine-resistant mutants of UL97 and UL54 was identical to that of the parent Towne strain, indicating the different anti-CMV action from ganciclovir, foscarnet, and maribavir. Mizoribine as an immunosuppressive and anti-CMV drug in the clinical regimen was suggested to suppress replication of CMV in vivo and control CMV infection in transplant recipients in combination with ganciclovir.
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Affiliation(s)
- Takashi Kuramoto
- Department of Virology, University of Toyama, Sugitani, Toyama, Japan
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Ichinose K, Origuchi T, Kawashiri SY, Iwamoto N, Fujikawa K, Aramaki T, Kamachi M, Arima K, Tamai M, Nakamura H, Ida H, Kawakami A, Tsukada T, Ueki Y, Eguchi K. Efficacy and safety of mizoribine by one single dose administration for patients with rheumatoid arthritis. Intern Med 2010; 49:2211-8. [PMID: 20962439 DOI: 10.2169/internalmedicine.49.3810] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE Mizoribine (MZR) is an immunosuppressant that inhibits nucleic acid metabolism and is a relatively safe disease-modifying anti-rheumatic drug (DMARD). We evaluated the efficacy and safety of one single dose per day for patients with rheumatoid arthritis (RA). PATIENTS AND METHODS In this study 32 patients with RA received MZR therapy. We evaluated the average dose of MZR and prednisolone, response to treatment and peak plasma level of MZR. RESULTS The average dose of MZR was 146.1±31.2 (range: 50-200) mg/day. The average dose of prednisolone was 4.63±3.59 (range: 0-14) mg/day. The average plasma level of MZR, measured after 3 hours, was 2.20±0.49 µg/mL in the responder group and 1.59±0.82 µg/mL in the non-responder group (p=0.020). The treatment with MZR for 24 weeks was completed by 71.9% of patients and the proportion of patients who achieved a good and moderate response rate according to the European League Against Rheumatism (EULAR) criteria was 56.3% at 24 weeks. The plasma level of MZR which was greater than or equal to 2.12 µg/mL was significantly correlated with the clinical response (p<0.01). Only one of thirty-two cases discontinued the treatment, because of skin eruption. CONCLUSION This study included patients that could not be treated with other DMARDs and/or biologic agents because of age, interstitial pneumonia and other complications. We show that MZR may be a useful and relatively safe therapy for patients in this group.
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Affiliation(s)
- Kunihiro Ichinose
- Department of Rheumatology, Unit of Translational Medicine, Graduate School of Biomedical Sciences, Nagasaki University.
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Mizoribine: a new approach in the treatment of renal disease. Clin Dev Immunol 2009; 2009:681482. [PMID: 20052390 PMCID: PMC2801010 DOI: 10.1155/2009/681482] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 08/06/2009] [Accepted: 09/16/2009] [Indexed: 11/18/2022]
Abstract
Mizoribine (MZB) is an imidazole nucleoside and an immunosuppressive agent. The immunosuppressive effect of MZB has been reported to be due to the inhibition of DNA synthesis in the S phase of the cell cycle. Because of its relative lack of toxicity, during the past decade MZB has been frequently used instead of azathioprine as a component of immunosuppressive drug regimens. MZB is being used to treat renal transplantation patients, IgA nephropathy, lupus erythematosus, and childhood nephrotic syndrome (NS), and some recent studies have assessed the efficacy of oral MZB pulse therapy for severe lupus nephritis, steroid-resistant NS, and frequently relapsing-steroid-dependent NS.
This review summarizes the published findings on the efficacy of MZB for renal disease including IgA nephropathy, lupus nephritis, and NS, as well as of oral MZB pulse therapy for severe lupus nephritis and NS, and also the mechanism of the effect of oral MZB pulse therapy on the lymphocyte cell cycle.
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Efficacy of mizoribine pulse therapy in patients with rheumatoid arthritis who show a reduced or insufficient response to infliximab. Mod Rheumatol 2009; 19:229-34. [PMID: 19326186 PMCID: PMC2689357 DOI: 10.1007/s10165-009-0162-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Accepted: 02/13/2009] [Indexed: 10/27/2022]
Abstract
The efficacy of infliximab, a chimeric antibody against tumor necrosis factor-alpha used to treat patients with rheumatoid arthritis (RA), tends to decrease as patients develop human antichimeric antibody against infliximab (HACA). The clinical study reported here was designed to evaluate the efficacy of mizoribine (MZR) pulse therapy in patients who show a reduced or insufficient response to infliximab. Ten RA patients who had active arthritis despite infliximab therapy were treated with MZR pulse therapy at a dose of 100 mg MZR and methotrexate (MTX) and the disease activity assessed at baseline and at weeks 4-8, 12-16, and 20-24. The dose was increased to 150 mg in those patients who showed an insufficient response to MZR. The mean 28-joint disease activity score (DAS28) at weeks 12-16 and 20-24 of therapy was significantly lower than that at baseline. A moderate or good European League against Rheumatism (EULAR) response was achieved in seven patients (70%) at weeks 12-16 and in five patients (50%) at weeks 20-24. The dose of 150 mg MZR was effective in one of the three patients who showed an insufficient response to pulse therapy with 100 mg MZR. Based on these results, we propose that MZR pulse therapy should be attempted before the patient is switched to other biologics.
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A simple HPLC method for the quantification of mizoribine in human serum: pharmacokinetic applications. Biomed Chromatogr 2008; 22:1259-64. [DOI: 10.1002/bmc.1055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Perico N, Remuzzi G. Section Review Pulmonary-Allergy, Dermatological, Gastrointestinal & Arthritis: New antirejection drugs. Expert Opin Ther Pat 2008. [DOI: 10.1517/13543776.6.9.871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wang F, Tan W, Guo D, He S. Reduction of CD4 positive T cells and improvement of pathological changes of collagen-induced arthritis by FTY720. Eur J Pharmacol 2007; 573:230-40. [PMID: 17716652 DOI: 10.1016/j.ejphar.2007.07.029] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2007] [Revised: 06/29/2007] [Accepted: 07/04/2007] [Indexed: 11/16/2022]
Abstract
FTY720 belongs to a new class of immunosuppressants. Little is known about its influence on T cell subtypes and pathological changes in arthritis. Here we illustrated the effect of FTY720 on peripheral T cell subsets and joint damage of collagen-induced arthritis rats. Rats were administered FTY720 or prednisone daily from day 0 to day 28. Body weight, hind paw swelling and arthritis index were measured. Bone destruction was determined by micro-computed tomography and histopathology, and T cell subsets were analyzed by flow cytometry and immunohistochemistry. The results showed that FTY720 inhibited the development of arthritis. Radiological analysis revealed that FTY720 treated collagen-induced arthritic rats had much less joint damage in comparison to untreated collagen-induced arthritic rats. Histological study showed that collagen-induced arthritic rats suffered from inflammatory cell infiltration and synovial hyperplasia in their joints, and FTY720 treatment clearly reduced these pathological changes. Immunohistochemical analysis showed that FTY720 treatment significantly decreased the number of CD4(+) T cells in the synovium of collagen-induced arthritic rats. Collagen-induced arthritic rats appeared to have more CD4(+), but not CD8(+) T cells in their peripheral blood than normal control rats. Following FTY720 treatment, peripheral blood CD3(+) and CD4(+) T cells in collagen-induced arthritic rats were significantly decreased. In conclusion, FTY720 is an effective compound in the treatment of collagen-induced arthritic rats and in reducing CD4(+) T cells in collagen-induced arthritic rats.
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Affiliation(s)
- Fang Wang
- The Clinical Experiment Center, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
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Honda M, Itoh H, Suzuki T, Hashimoto Y. Population pharmacokinetics of higher-dose mizoribine in healthy male volunteers. Biol Pharm Bull 2007; 29:2460-4. [PMID: 17142982 DOI: 10.1248/bpb.29.2460] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The population pharmacokinetic parameters of mizoribine in healthy subjects were estimated using a nonlinear mixed effects model (NONMEM) program. Pharmacokinetic data for population analysis were obtained in the previous study, in which 24 healthy Caucasian male subjects participated in a single-dose (3, 6, 9, 12 mg/kg) study, and 12 subjects participated in a multiple-dose (6, 12 mg/kg/d) study. The mean value of the absorption lag time, absorption rate constant (KA), and apparent distribution volume (V/F) was estimated to be 0.349 h, 0.869 h-1, and 0.834 l/kg, respectively. Oral clearance (CL/F) was modeled with creatinine clearance (CLcr), and the mean value was estimated to be 1.93.CLcr l/h. In addition, pharmacokinetic parameters in individual 36 subjects were obtained from population estimates according to Bayes' theorem. Pharmacokinetic parameters (KA, V/F, and CL/F) in the single-dose study were almost constant at a dose range of 3-12 mg/kg, and were similar to those in the multiple-dose study. These findings indicated that the pharmacokinetics of mizoribine is well described by a simple one-compartment model with first-order absorption.
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Affiliation(s)
- Mutsuko Honda
- Graduate School of Pharmaceutical Sciences, University of Toyama, Japan
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Stypinski D, Obaidi M, Combs M, Weber M, Stewart AJ, Ishikawa H. Safety, tolerability and pharmacokinetics of higher-dose mizoribine in healthy male volunteers. Br J Clin Pharmacol 2006; 63:459-68. [PMID: 17096684 PMCID: PMC2203250 DOI: 10.1111/j.1365-2125.2006.02779.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIMS Mizoribine is an oral immunosuppressive agent approved in several countries for prevention of rejection in renal transplantation. Its therapeutic window is based on trough concentrations staying at > or =0.5 but <3 microg ml(-1). It has been postulated that as renal function returns to normal, higher doses may be needed to maintain efficacy than the current clinical dosage of 2-5 mg kg(-1) day(-1). The safety, tolerability and pharmacokinetics from two clinical trials of higher-dose mizoribine treatments in healthy male volunteers are presented. METHODS Forty-eight healthy White male nonsmokers participated in two randomized, double-blind, placebo-controlled trials: 32 in a single-dose study (3, 6, 9 and 12 mg kg(-1)) and 16 in a multiple-dose study [6 mg kg(-1) day(-1) once daily for 5 days or twice daily (12 mg kg(-1) day(-1)) for 7 days]. Standard assessments of safety, tolerability and pharmacokinetics were performed. RESULTS The safety profiles of both studies were generally unremarkable, except for elevated serum uric acid concentrations at the highest dose (12 mg kg(-1) day(-1)) in the multiple-dose study. Orally administered mizoribine reached peak concentrations within 2-3 h and was eliminated mostly via the kidney (65-100% of dose) with a 3-h half-life. Only the 12 mg kg(-1) day(-1) group achieved trough concentrations that were within the therapeutic window. Conclusions Based on the favourable safety profile and current pharmacokinetic information, a new starting dose in the 6-12 mg kg(-1) day(-1) range is recommended in the up to 3 months acute phase following transplantation, with dose reduction recommended only if the function of the transplanted kidney is impaired.
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Tanaka E, Inoue E, Kawaguchi Y, Tomatsu T, Yamanaka H, Hara M, Kamatani N. Acceptability and usefulness of mizoribine in the management of rheumatoid arthritis in methotrexate-refractory patients and elderly patients, based on analysis of data from a large-scale observational cohort study. Mod Rheumatol 2006; 16:214-9. [PMID: 16906370 DOI: 10.1007/s10165-006-0487-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 04/27/2006] [Indexed: 10/24/2022]
Abstract
This report documents the results of a study performed to examine clinical use of mizoribine (MZR), using data from a large-scale prospective cohort study, IORRA (Institute of Rheumatology Rheumatoid Arthritis). The number of patients with RA entered in this study from October 2000 through October 2003 was 6238. Three hundred and six patients (4.9%) received MZR therapy. Mizoribine users who were taking methotrexate (MTX) (MTX-MZR group, n = 94) and over 70 years of age (elderly group, n = 45) were collected. Cumulative retention rates of MZR were calculated by Kaplan-Meier analysis. Median drug survival of MZR was 28 months for the poor responders to MTX and 43 months for the poor responders to MZR, with no significant difference between these groups. Cumulative retention rate of MZR in the elderly group did not show a significant difference compared to that in patients aged under 70 years. Ten patients (10.6%) in the MTX-MZR group and 10 patients (22.2%) in the elderly group experienced adverse effects of MZR. None of these adverse effects was serious. This study indicated that, although MZR has not been frequently prescribed for RA patients, it may be useful and relatively safe for patients who are poor responders to MTX as an additional regimen to MTX therapy as well as for elderly patients.
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Affiliation(s)
- Eiichi Tanaka
- Institute of Rheumatology, Tokyo Women's Medical University, 10-22 Kawada-cho, Shinjuku-ku, Tokyo, 162-0054, Japan
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Sandbhor U, Kulkarni P, Padhye S, Kundu G, Mackenzie G, Pritchard R. Antimelanomal activity of the copper(II) complexes of 1-substituted 5-amino-imidazole ligands against B16F10 mouse melanoma cells. Bioorg Med Chem Lett 2004; 14:2877-82. [PMID: 15125951 DOI: 10.1016/j.bmcl.2004.03.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Revised: 03/13/2004] [Accepted: 03/15/2004] [Indexed: 11/26/2022]
Abstract
The copper complexes of 5-amino-imidazole ligands were prepared and characterized by various spectroscopic techniques. The ligand geometry around the copper(II) centre is square pyramidal based on N2O2 donor atoms and a coordinated water molecule at the apex. Single crystal X-ray structures were determined for both ligands. Ligands and copper complexes exhibited dose-dependent antiproliferative effects on the growth of B16F10 melanoma cells line but lower IC50 values were observed for the copper complexes.
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Affiliation(s)
- Uday Sandbhor
- Department of Chemistry, University of Pune, Pune 411007, India.
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Tanaka H, Abe T, Nishimura S, Sakai H, Kimura H, Oki M, Nojima M, Taga M, Matsumoto SI, Takahashi H, Imai K. A case of rheumatoid arthritis/Sjogren's syndrome with acute renal failure due to hyperuricemia associated with mizoribine therapy. ACTA ACUST UNITED AC 2004; 27:171-6. [PMID: 15291254 DOI: 10.2177/jsci.27.171] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A 64-year-old woman was diagnosed as having rheumatoid arthritis in 1999 at a nearby hospital. She had been treated with etodolac, actarit, mizoribine (MZ) and prednisolone. On May 25, 2001, she noticed fever and nausea and was treated with diclofenac sodium and clindamycin. On May 31, a nasal bleeding, tarry stool, hyperuricemia, renal dysfunction and thrombocytopenia developed and she was admitted to our hospital. Administration of drugs except prednisolone was stopped and hemodialysis was carried out on June 1. Fever and nausea improved during several days. Hyperuricemia and renal dysfunction disappeared on June 11. The platelet count became normal after platelet transfusion and she was discharged from our hospital on July 2. She was also diagnosed as having Sjogren's syndrome. In our case, a delay in MZ discharge by transient renal dysfunction might have caused a hyperuricemia, following an aggravation of renal dysfunction. So, care should be taken about latent renal dysfunction during the use of MZ. Moreover, it may be necessary to consider a discontinuation of MZ and administration of hemodialysis in the case of transient renal dysfunction.
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Affiliation(s)
- Hiroki Tanaka
- Department of Internal Medicine, Kushiro City General Hospital
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Nagahara Y, Ikekita M, Shinomiya T. T cell selective apoptosis by a novel immunosuppressant, FTY720, is closely regulated with Bcl-2. Br J Pharmacol 2002; 137:953-62. [PMID: 12429567 PMCID: PMC1573588 DOI: 10.1038/sj.bjp.0704970] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. A novel immunosuppressant FTY720 caused a significant decrease in peripheral T lymphocytes, but not in B lymphocytes upon oral administration. This decrease was mainly a result of FTY720-induced apoptosis. In this study, we confirmed FTY720-induced T cell selective apoptosis using lymphoma cell lines in vitro. 2. Viability loss, DNA fragmentation, Annexin V binding, and caspases activation (caspase-3, -8, and -9) were observed in Jurkat cells (T lymphoma cells), but not significantly in BALL-1 cells (B lymphoma cells). These results indicated that FTY720 selectively induced apoptosis in T cell lymphoma to a greater extent than in B cell lymphoma, a finding that is similar to the result observed when FTY720 was treated with T lymphocytes and B lymphocytes in vitro. 3. FTY720 released cytochrome c from mitochondria in Jurkat intact cells as well as from isolated Jurkat mitochondria directly, but not from mitochondria in BALL-1 cells nor from isolated BALL-1 mitochondria. 4. BALL-1 cells and B cells had more abundant mitochondria-localized anti-apoptotic protein Bcl-2 than did Jurkat cells and T cells. 5. FTY720-induced apoptosis is inhibited by the overexpression of Bcl-2, suggesting that the cellular Bcl-2 level regulates the sensitivity to FTY720.
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Affiliation(s)
- Yukitoshi Nagahara
- Division of Radio Isotopes and Biosafety Research, National Research Institute for Child Health and Development, 3-35-31 Taishido, Setagaya-ku, Tokyo 154-8567, Japan
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Masahiko Ikekita
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
| | - Takahisa Shinomiya
- Division of Radio Isotopes and Biosafety Research, National Research Institute for Child Health and Development, 3-35-31 Taishido, Setagaya-ku, Tokyo 154-8567, Japan
- Author for correspondence:
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Sato N, Shiraiwa K, Kai K, Watanabe A, Ogawa S, Kobayashi Y, Yamagishi-Imai H, Utsunomiya Y, Mitarai T. Mizoribine ameliorates the tubulointerstitial fibrosis of obstructive nephropathy. Nephron Clin Pract 2001; 89:177-85. [PMID: 11549900 DOI: 10.1159/000046065] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Mizoribine has been shown to possess an immunosuppressive action that inhibits the proliferation of lymphocytes selectively by interfering with inosine monophosphate dehydrogenase. Recent studies have demonstrated that mizoribine improves renal tubulointerstitial fibrosis in the rat model of unilateral ureteral obstruction (UUO) by inhibiting the infiltration of macrophages. We, therefore, examined the dose dependency of the suppressive effect of mizoribine on the infiltration of interstitial macrophages and T lymphocytes and the interstitial volume in UUO-treated kidneys. Furthermore, we investigated the expression of osteopontin (OPN), known to be a chemoattractant protein for macrophages, in the renal cortex. In rats with UUO, the interstitial volume was markedly expanded, and macrophage and T lymphocyte infiltration in the interstitium and the expression of OPN in the cortical tubules were greatly increased. Treatment with mizoribine ameliorated the increase in interstitial volume induced by UUO. Interstitial infiltration of macrophages and T lymphocytes was dose dependently suppressed by mizoribine, and the decreased macrophage infiltration was correlated with inhibition of tubular OPN expression. These results suggest that mizoribine has a beneficial effect on several steps contributing to the progression of tubulointerstitial fibrosis caused by obstruction of the ureter.
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Affiliation(s)
- N Sato
- Laboratory for Toxicological Research, Institute for Life Science Research, Asahi Chemical Industry Co., Ltd., Shizuoka, Japan.
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Sugiyama E, Ikemoto M, Taki H, Maruyama M, Yamashita N, Kobayashi M. Mizoribine, an inhibitor of inosine monophosphate dehydrogenase, inhibits interleukin-6 production by freshly prepared rheumatoid synovial cells. Mod Rheumatol 2001; 11:28-33. [PMID: 24387017 DOI: 10.3109/s101650170040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract Mizoribine, an immunosuppressive drug, has been used for treatment in organ transplantation, lupus nephritis, and rheumatoid arthritis (RA). On the basis of in vitro experiments, mizoribine has been postulated to be an inhibitor of inosine monophosphate (IMP) dehydrogenase, a pivotal enzyme in the formation of guanine ribonucleotides from IMP. To further characterize the mechanism of the antirheumatic action of this drug, we examined the effect of mizoribine on the production of interleukin (IL)-6, a major inflammatory cytokine in rheumatoid synovia, by freshly prepared rheumatoid synovial cells (RSC). Mizoribine (1.25-5 μg/ml) was able to inhibit the spontaneous production of IL-6 by fresh RSC in a dose-response fashion. The addition of guanosine monophosphate (GMP) reversed its inhibitory effects. In addition, mizoribine inhibited the enhanced production of IL-6 by the IL-1α and/or tumor necrosis factor α-stimulated RSC. Inhibition was also observed at the mRNA level, determined by Northern blot analysis. In contrast, mizoribine did not affect IL-8 production by these cells. These data suggest that mizoribine inhibits IL-6 production by fresh RSC, possibly owing to the depletion of intracellular GMP, and that this inhibitory effect of the drug on rheumatoid synovial cells may be related to its efficacy in RA.
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Affiliation(s)
- E Sugiyama
- First Department of Internal Medicine, Toyama Medical and Pharmaceutical University , 2630 Sugitani, Toyama 930-0194 , Japan
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Metz S, Holland S, Johnson L, Espling E, Rabaglia M, Segu V, Brockenbrough JS, Tran PO. Inosine-5'-monophosphate dehydrogenase is required for mitogenic competence of transformed pancreatic beta cells. Endocrinology 2001; 142:193-204. [PMID: 11145582 DOI: 10.1210/endo.142.1.7869] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The relation of inosine-5'-monophosphate dehydrogenase (IMPDH; the rate-limiting enzyme in GTP synthesis) to mitogenesis was studied by enzymatic assay, immunoblots, and RT-PCR in several dissimilar transformed pancreatic ss-cell lines, using intact cells. Both of the two isoforms of IMPDH (constitutive type 1 and inducible type 2) were identified using RT-PCR in transformed beta cells or in intact islets. IMPDH 2 messenger RNA (mRNA) and IMPDH protein were both regulated reciprocally by changes in levels of their end-products. Flux through IMPDH was greatest in rapidly growing cells, due mostly to increased uptake of precursor. Glucose (but not 3-0-methylglucose, L-glucose, or fructose) further augmented substrate uptake and also increased IMPDH enzymatic activity after either 4 or 21 h of stimulation. Serum or ketoisocaproate also increased IMPDH activity (but not uptake). Two selective IMPDH inhibitors (mycophenolic acid and mizoribine) reduced IMPDH activity in all cell lines, and, with virtually identical concentration-response curves, inhibited DNA synthesis (assessed as bromodeoxyuridine incorporation) in response to glucose, serum, or ketoisocaproate. Inhibition of DNA synthesis was reversible, completely prevented by repletion of cellular guanine (but not adenine) nucleotides, and could not be attributed to toxic effects. Despite the fact that modulation of IMPDH expression by guanine nucleotides was readily detectable, glucose and/or serum failed to alter IMPDH mRNA or protein, indicating that their effects on IMPDH activity were largely at the enzyme level. Precursors of guanine nucleotides failed, by themselves, to induce mitogenesis. Thus, adequate IMPDH activity (and thereby, availability of GTP) is a critical requirement for beta-cell proliferation. Although it is unlikely that further increases in GTP can, by themselves, initiate DNA synthesis, such increments may be needed to sustain mitogenesis.
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Affiliation(s)
- S Metz
- Diabetes Laboratories, Pacific Northwest Research Institute, Seattle, Washington 98122, USA.
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Takahashi S, Wakui H, Gustafsson JA, Zilliacus J, Itoh H. Functional interaction of the immunosuppressant mizoribine with the 14-3-3 protein. Biochem Biophys Res Commun 2000; 274:87-92. [PMID: 10903900 DOI: 10.1006/bbrc.2000.3104] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mizoribine (MIZ) is a novel imidazole nucleoside with immunosuppressive activity. MIZ has been approved in Japan and combination therapy with MIZ and glucocorticoids has been used after renal transplantation and for lupus nephritis and rheumatoid arthritis. In this study, we identify 14-3-3 proteins as MIZ-binding proteins. 14-3-3 proteins interact with many proteins involved in cellular signaling, including the glucocorticoid receptor (GR). The 14-3-3/GR interaction enhances the transcriptional activity of the receptor. We show that MIZ affects the conformation of 14-3-3 proteins and enhances the interaction of GR and 14-3-3eta dose dependently in vitro. MIZ also has a stimulatory effect on transcriptional activation by the GR. Our results point to the possibility that one mechanism for the therapeutic effect of MIZ could be to regulate the GR function via 14-3-3 proteins.
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Affiliation(s)
- S Takahashi
- Department of Medical Nutrition, Karolinska Institutet, Novum, Huddinge, S-141 86, Sweden
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41
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Nagahara Y, Enosawa S, Ikekita M, Suzuki S, Shinomiya T. Evidence that FTY720 induces T cell apoptosis in vivo. IMMUNOPHARMACOLOGY 2000; 48:75-85. [PMID: 10822091 DOI: 10.1016/s0162-3109(00)00181-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The immunosuppressant FTY720 induces a drastic decrease in blood lymphocytes, especially T cells; a decrease which is assumed to be the immunosuppressive mechanism of this drug. FTY720 causes cell death in vitro in lymphocytes and leukemia cells. However, the deletion mechanism of blood lymphocytes in vivo remains unclear. We investigated whether administration of FTY720 induced lymphocyte apoptosis in blood circulation. A marked decrease in the number of blood lymphocytes was observed within an hour after a single oral administration of FTY720 at doses of 5-10 mg/kg in rats and mice. Experiments using fluorescein isothiocyanate (FITC)-Annexin V and APO-BRDU methods revealed that FTY720 induced blood lymphocyte apoptosis in a dose-dependent manner. On the other hand, lymphocyte homing to Peyer's patches was proposed as the mechanism underlying the blood lymphocyte decrease at these doses. However, similar results were obtained when using aly/aly mice, which lack Peyer's patches and lymph nodes. Thus, we concluded that apoptosis of blood lymphocytes was induced immediately after administration of FTY720, and the cells could be immediately scavenged by phagocytes or the reticuloendothelial system in addition to Peyer's patches homing. We also concluded that T cells were highly sensitive to FTY720, which induced apoptosis in vivo.
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Affiliation(s)
- Y Nagahara
- Division of Research Promotion, National Children's Medical Research Center, 3-35-31 Taishido, Setagaya-ku, Tokyo 154-8509, Japan
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42
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Itoh H, Komatsuda A, Wakui H, Miura AB, Tashima Y. Mammalian HSP60 is a major target for an immunosuppressant mizoribine. J Biol Chem 1999; 274:35147-51. [PMID: 10574997 DOI: 10.1074/jbc.274.49.35147] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has been reported that immunosuppressant cyclosporin A or FK506 binds to immunophilins in the cell and that these immunophilins make a complex with molecular chaperones HSP70 or HSP90. Although mizoribine has been used clinically as an immunosuppressant, immunophilins of the agent have not yet been fully understood. We investigated their specific binding proteins using mizoribine affinity column chromatography and porcine kidney cytosols. By increasing mizoribine in the eluant from the column, two major proteins (with molecular masses of 60 and 43 kDa) were detected by SDS-polyacrylamide gel electrophoresis. Based on the amino acid sequence analysis of these proteins, 60- and 43-kDa mizoribine-binding proteins were identified with HSP60 and cytosolic actin, respectively. A considerable amount of actin was also eluted from the affinity column by nucleotides, but a very low quantity of HSP60 was eluted under the same conditions. On the other hand, HSP60 was eluted as a major protein in the eluant that was eluted preferentially, with nucleotide followed by mizoribine. Actin was also detected in the eluant, but the quantity of the protein was very low. These results indicated that HSP60 has high affinity to mizoribine, and the interaction was also observed on surface plasmon resonance analysis. Although HSP60 or GroE facilitated refolding of citrate synthase in vitro, mizoribine interfered with the chaperone activity of HSP60. On different types of mizoribine affinity columns, HSP60 or actin recognized the NH(2) group of mizoribine, and this group may be a functional group of the agent.
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Affiliation(s)
- H Itoh
- Department of Biochemistry, Akita University School of Medicine, 1-1-1 Hondo, Akita City 010-8543, Japan.
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43
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Gerber DA, Bonham CA, Thomson AW. Immunosuppressive agents: recent developments in molecular action and clinical application. Transplant Proc 1998; 30:1573-9. [PMID: 9636637 DOI: 10.1016/s0041-1345(98)00361-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- D A Gerber
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, PA 15213, USA
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44
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The synergistic effect of bactobolamine and tacrolimus on in vitro and in vivo experiments. Surg Today 1997. [DOI: 10.1007/bf02385686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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45
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Meredith M, Li G, Metz SA. Inhibition of calcium-induced insulin secretion from intact HIT-T15 or INS-1 beta cells by GTP depletion. Biochem Pharmacol 1997; 53:1873-82. [PMID: 9256162 DOI: 10.1016/s0006-2952(97)00057-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Using intact rat islets, we previously observed that GTP depletion (achieved through the use of mycophenolic acid or other synthesis inhibitors) impedes nutrient- but not K+-induced insulin secretion. It was concluded that a proximal nutrient-dependent step in stimulus-secretion coupling (but not the process of Ca2+-induced exocytosis itself) is modulated by ambient GTP levels. To examine Ca2+-dependent steps further in intact beta cells, INS-1 cells (which synthesize GTP and ATP similarly to rat islets) and HIT-T15 cells (whose synthesis of purine nucleotides is different) were studied following cell culture for 1-18 hr in various concentrations of mycophenolic acid (MPA) or mizoribine (MZ). Both agents profoundly reduced GTP content (mean: -78%) and lowered the GTP/GDP ratio by an average of -73%; concomitantly, MPA or MZ reduced insulin secretion induced by 10 mM glucose, 30 or 40 mM KCl, or 100 microM tolbutamide, independent of any changes in cell viability, insulin content, ATP content, the ATP/ADP ratio, or cytosolic free Ca2+ concentrations. In INS-1 cells (which appear to have normal nucleobase transport and "salvage" pathway activities), guanine (but not adenine) restored GTP content, the GTP/GDP ratio, and Ca2+-induced secretion. In HIT cells, the phosphoribosylation of exogenous guanine or hypoxanthine is defective; however, provision of 500 microM guanosine (but not adenosine) reversed the effects of MPA. We conclude that, at least in certain situations, a requisite role for GTP in the distal step(s) of exocytosis can be demonstrated.
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Affiliation(s)
- M Meredith
- Department of Medicine, University of Wisconsin and the William S. Middleton Veteran's Administration Hospital, Madison, USA
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46
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Hiroyuki K, Hiromichi I, Hiroshi S, Takehiro K, Akira H, Keiji N. Inhibitory Mechanism of Mizoribine on the Antibody Production of Mouse B Cells Stimulated with Lipopolysaccharide. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0021-5198(19)31365-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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47
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Abstract
An examination of the mechanisms by which four new immunosuppressive drugs--rapamycin, mizoribine, mycophenolate mofetil, and 15-deoxyspergualin--exert their effects reveals three major categories. Rapamycin binds to an intracellular immunophilin. The resulting drug-immunophilin complex inhibits the action of cytokines, thus blocking the activation and proliferation of T cells. Mizoribine and mycophenolate mofetil are antimetabolites that inhibit a key enzyme in the de novo purine biosynthetic pathway. As a result, the proliferation of T cells and B cells is inhibited selectively compared with that of nonlymphoid cells because the salvage pathway is unavailable to lymphocytes. Finally, 15-deoxyspergualin has a unique mechanism of action, which includes suppressive effects on macrophage function, the induction of cytolytic T cells, B-cell reactivity, and antibody responses. The demonstrated synergism among certain immunosuppressants allows reduction in the dose of each agent to minimize the individual toxicities. As more of these new agents become available, it is likely that azathioprine will be replaced, and it may be possible to eliminate the need for long-term maintenance steroid therapy.
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Affiliation(s)
- S E Hughes
- Department of Surgery, Albany Medical College, New York, USA
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48
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Kahan BD. The three fates of immunosuppression in the next millenium: selectivity, synergy, and specificity. Transpl Int 1996; 9:527-34. [PMID: 8914230 DOI: 10.1007/bf00335550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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49
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Kahan BD. The three fates of immuno suppression in the next millenium: selectivity, synergy, and specificity. Transpl Int 1996. [DOI: 10.1111/j.1432-2277.1996.tb00909.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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50
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Kahan BD. SOLID ORGAN TRANSPLANTATION. Radiol Clin North Am 1996. [DOI: 10.1016/s0033-8389(22)00210-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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