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Peres RAS, Peruchetti DB, Silva-Aguiar RP, Teixeira DE, Gomes CP, Takiya CM, Pinheiro AAS, Caruso-Neves C. Rapamycin treatment induces tubular proteinuria: role of megalin-mediated protein reabsorption. Front Pharmacol 2023; 14:1194816. [PMID: 37484026 PMCID: PMC10359992 DOI: 10.3389/fphar.2023.1194816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/27/2023] [Indexed: 07/25/2023] Open
Abstract
Introduction: Rapamycin is an immunosuppressor that acts by inhibiting the serine/threonine kinase mechanistic target of rapamycin complex 1. Therapeutic use of rapamycin is limited by its adverse effects. Proteinuria is an important marker of kidney damage and a risk factor for kidney diseases progression and has been reported in patients and animal models treated with rapamycin. However, the mechanism underlying proteinuria induced by rapamycin is still an open matter. In this work, we investigated the effects of rapamycin on parameters of renal function and structure and on protein handling by proximal tubule epithelial cells (PTECs). Methods: Healthy BALB/c mice were treated with 1.5 mg/kg rapamycin by oral gavage for 1, 3, or 7 days. At the end of each treatment, the animals were kept in metabolic cages and renal function and structural parameters were analyzed. LLC-PK1 cell line was used as a model of PTECs to test specific effect of rapamycin. Results: Rapamycin treatment did not change parameters of glomerular structure and function. Conversely, there was a transient increase in 24-h proteinuria, urinary protein to creatinine ratio (UPCr), and albuminuria in the groups treated with rapamycin. In accordance with these findings, rapamycin treatment decreased albumin-fluorescein isothiocyanate uptake in the renal cortex. This effect was associated with reduced brush border expression and impaired subcellular distribution of megalin in PTECs. The effect of rapamycin seems to be specific for albumin endocytosis machinery because it did not modify renal sodium handling or (Na++K+)ATPase activity in BALB/c mice and in the LLC-PK1 cell line. A positive Pearson correlation was found between megalin expression and albumin uptake while an inverse correlation was shown between albumin uptake and UPCr or 24-h proteinuria. Despite its effect on albumin handling in PTECs, rapamycin treatment did not induce tubular injury measured by interstitial space and collagen deposition. Conclusion: These findings suggest that proteinuria induced by rapamycin could have a tubular rather than a glomerular origin. This effect involves a specific change in protein endocytosis machinery. Our results open new perspectives on understanding the undesired effect of proteinuria generated by rapamycin.
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Affiliation(s)
- Rodrigo A. S. Peres
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Diogo B. Peruchetti
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Rodrigo P. Silva-Aguiar
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Douglas E. Teixeira
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carlos P. Gomes
- Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- School of Medicine and Surgery, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Christina M. Takiya
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Acacia S. Pinheiro
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Rio de Janeiro Innovation Network in Nanosystems for Health-NanoSAÚDE/FAPERJ, Rio de Janeiro, Brazil
| | - Celso Caruso-Neves
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Rio de Janeiro Innovation Network in Nanosystems for Health-NanoSAÚDE/FAPERJ, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Regenerative Medicine, Rio de Janeiro, Brazil
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2
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Martin DE, Cadar AN, Panier H, Torrance BL, Kuchel GA, Bartley JM. The effect of metformin on influenza vaccine responses in nondiabetic older adults: a pilot trial. Immun Ageing 2023; 20:18. [PMID: 37131271 PMCID: PMC10152024 DOI: 10.1186/s12979-023-00343-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/24/2023] [Indexed: 05/04/2023]
Abstract
BACKGROUND Aging is associated with progressive declines in immune responses leading to increased risk of severe infection and diminished vaccination responses. Influenza (flu) is a leading killer of older adults despite availability of seasonal vaccines. Geroscience-guided interventions targeting biological aging could offer transformational approaches to reverse broad declines in immune responses with aging. Here, we evaluated effects of metformin, an FDA approved diabetes drug and candidate anti-aging drug, on flu vaccination responses and markers of immunological resilience in a pilot and feasibility double-blinded placebo-controlled study. RESULTS Healthy older adults (non-diabetic/non-prediabetic, age: 74.4 ± 1.7 years) were randomized to metformin (n = 8, 1500 mg extended release/daily) or placebo (n = 7) treatment for 20 weeks and were vaccinated with high-dose flu vaccine after 10 weeks of treatment. Peripheral blood mononuclear cells (PBMCs), serum, and plasma were collected prior to treatment, immediately prior to vaccination, and 1, 5, and 10 weeks post vaccination. Increased serum antibody titers were observed post vaccination with no significant differences between groups. Metformin treatment led to trending increases in circulating T follicular helper cells post-vaccination. Furthermore, 20 weeks of metformin treatment reduced expression of exhaustion marker CD57 in circulating CD4 T cells. CONCLUSIONS Pre-vaccination metformin treatment improved some components of flu vaccine responses and reduced some markers of T cell exhaustion without serious adverse events in nondiabetic older adults. Thus, our findings highlight the potential utility of metformin to improve flu vaccine responses and reduce age-related immune exhaustion in older adults, providing improved immunological resilience in nondiabetic older adults.
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Affiliation(s)
- Dominique E Martin
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
- Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
| | - Andreia N Cadar
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
- Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
| | - Hunter Panier
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
- Department of Medicine, University of Connecticut School of Medicine, Farmington Avenue, Farmington, CT, 06030, USA
| | - Blake L Torrance
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
- Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
| | - George A Kuchel
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA
| | - Jenna M Bartley
- UConn Center On Aging, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA.
- Department of Immunology, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT, 06030, 860-679-8322, USA.
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Molecular and therapeutic insights of rapamycin: a multi-faceted drug from Streptomyces hygroscopicus. Mol Biol Rep 2023; 50:3815-3833. [PMID: 36696023 PMCID: PMC9875782 DOI: 10.1007/s11033-023-08283-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 01/13/2023] [Indexed: 01/26/2023]
Abstract
The advancement in pharmaceutical research has led to the discovery and development of new combinatorial life-saving drugs. Rapamycin is a macrolide compound produced from Streptomyces hygroscopicus. Rapamycin and its derivatives are one of the promising sources of drug with broad spectrum applications in the medical field. In recent times, rapamycin has gained significant attention as of its activity against cytokine storm in COVID-19 patients. Rapamycin and its derivatives have more potency when compared to other prevailing drugs. Initially, it has been used exclusively as an anti-fungal drug. Currently rapamycin has been widely used as an immunosuppressant. Rapamycin is a multifaceted drug; it has anti-cancer, anti-viral and anti-aging potentials. Rapamycin has its specific action on mTOR signaling pathway. mTOR has been identified as a key regulator of different pathways. There will be an increased demand for rapamycin, because it has lesser adverse effects when compared to steroids. Currently researchers are focused on the production of effective rapamycin derivatives to combat the growing demand of this wonder drug. The main focus of the current review is to explore the origin, development, molecular mechanistic action, and the current therapeutic aspects of rapamycin. Also, this review article revealed the potential of rapamycin and the progress of rapamycin research. This helps in understanding the exact potency of the drug and could facilitate further studies that could fill in the existing knowledge gaps. The study also gathers significant data pertaining to the gene clusters and biosynthetic pathways involved in the synthesis and production of this multi-faceted drug. In addition, an insight into the mechanism of action of the drug and important derivatives of rapamycin has been expounded. The fillings of the current review, aids in understanding the underlying molecular mechanism, strain improvement, optimization and production of rapamycin derivatives.
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Nian Z, Zheng X, Dou Y, Du X, Zhou L, Fu B, Sun R, Tian Z, Wei H. Rapamycin Pretreatment Rescues the Bone Marrow AML Cell Elimination Capacity of CAR-T Cells. Clin Cancer Res 2021; 27:6026-6038. [PMID: 34233960 PMCID: PMC9401534 DOI: 10.1158/1078-0432.ccr-21-0452] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 05/26/2021] [Accepted: 06/30/2021] [Indexed: 01/07/2023]
Abstract
PURPOSE Ongoing clinical trials show limited efficacy for Chimeric antigen receptor (CAR) T treatment for acute myeloid leukemia (AML). The aim of this study was to identify potential causes of the reported limited efficacy from CAR-T therapies against AML. EXPERIMENTAL DESIGN We generated CAR-T cells targeting Epithelial cell adhesion molecule (EpCAM) and evaluated their killing activity against AML cells. We examined the impacts of modulating mTORC1 and mTORC2 signaling in CAR-T cells in terms of CXCR4 levels. We examined the effects of a rapamycin pretreatment of EpCAM CAR-T cells (during ex vivo expansion) and assessed the in vivo antitumor efficacy of rapamycin-pretreated EpCAM CAR-T cells (including CXCR4 knockdown cells) and CD33 CAR-T cells in leukemia xenograft mouse models. RESULTS EpCAM CAR-T exhibited killing activity against AML cells but failed to eliminate AML cells in bone marrow. Subsequent investigations revealed that aberrantly activated mTORC1 signaling in CAR-T cells results in decreased bone marrow infiltration and decreased the levels of the rapamycin target CXCR4. Attenuating mTORC1 activity with the rapamycin pretreatment increased the capacity of CAR-T cells to infiltrate bone marrow and enhanced the extent of bone marrow AML cell elimination in leukemia xenograft mouse models. CXCR4 knockdown experiments showed that CXCR4 contributes to the enhanced bone marrow infiltration capacity of EpCAM CAR-T cells and the observed reduction in bone marrow AML cells. CONCLUSIONS Our study reveals a potential cause for the limited efficacy of CAR-T reported from current AML clinical trials and illustrates an easy-to-implement pretreatment strategy, which enhances the anti-AML efficacy of CAR-T cells.See related commentary by Maiti and Daver, p. 5739.
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Affiliation(s)
- Zhigang Nian
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Xiaohu Zheng
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China.,Corresponding Authors: Haiming Wei, University of Science and Technology of China, 443 Huangshan Road, Hefei, Anhui 230027, China. Phone: 0551-6360-7379; E-mail: ; and Xiaohu Zheng, E-mail:
| | - Yingchao Dou
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Xianghui Du
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Li Zhou
- Department of Hematology, the First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Binqing Fu
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Rui Sun
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Zhigang Tian
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Haiming Wei
- Hefei National Laboratory for Physical Sciences at Microscale, The CAS Key Laboratory of Innate Immunity and Chronic Disease, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Institute of Immunology, University of Science and Technology of China, Hefei, China.,Corresponding Authors: Haiming Wei, University of Science and Technology of China, 443 Huangshan Road, Hefei, Anhui 230027, China. Phone: 0551-6360-7379; E-mail: ; and Xiaohu Zheng, E-mail:
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Liu T, Liang X, Sun Y, Yang S. Rapamycin suppresses the PI3K/AKT/mTOR signaling pathway by targeting SIRT1 in esophageal cancer. Exp Ther Med 2021; 22:1190. [PMID: 34475980 PMCID: PMC8406672 DOI: 10.3892/etm.2021.10624] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 06/29/2021] [Indexed: 12/13/2022] Open
Abstract
Rapamycin, a secondary metabolite produced by Streptomyces hygroscopicus, is known for its pharmacological effects, especially antitumor and immunosuppressive activities. However, the antitumoral effects of rapamycin in human esophageal cancer (EC) are still poorly understood. To investigate the potential of rapamycin in EC treatment, sirtuin 1 (SIRT1) mRNA expression was quantified in the tissue of patients with EC or in EC cell lines using reverse transcription-quantitative PCR. The protein levels of SIRT1 and PI3K/AKT/mTOR were measured via western blotting. Furthermore, cell viability, migration and invasion were investigated by Cell Counting Kit-8, wound healing and Transwell assays, respectively. The present results suggested that SIRT1 expression was upregulated in EC. In vitro, the inhibitory effect of rapamycin on cell viability in EC was strengthened or weakened after small interfering (si)-SIRT1 or pcDNA3.1/SIRT1 transfection. Furthermore, SIRT1 rescued the inhibitory effect of rapamycin on the migration and invasion of EC cells. In vivo, si-SIRT1 or SIRT1 overexpression in mice could enhance or rescue the inhibitory effects of rapamycin on tumor growth. In addition, SIRT1 transfection rescued the decreased level of phosphorylated (p)-PI3K, p-AKT and p-mTOR induced by rapamycin treatment. Taken together, the present results suggested that rapamycin suppressed the cell viability, migration, invasion and PI3K/AKT/mTOR signaling pathway in EC by negatively regulating SIRT1.
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Affiliation(s)
- Tao Liu
- Department of Cardiothoracic Surgery, Guangxi International Zhuang Medical Hospital, Nanning, Guangxi 530201, P.R. China
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530007, P.R. China
| | - Xiangsen Liang
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530007, P.R. China
| | - Yu Sun
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530007, P.R. China
| | - Shengzhuang Yang
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530007, P.R. China
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Si Y, Huang J, Li X, Fu Y, Xu R, Du Y, Cheng J, Jiang H. AKT/FOXO1 axis links cross-talking of endothelial cell and pericyte in TIE2-mutated venous malformations. Cell Commun Signal 2020; 18:139. [PMID: 32867785 PMCID: PMC7457504 DOI: 10.1186/s12964-020-00606-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 05/29/2020] [Indexed: 01/19/2023] Open
Abstract
Background Venous malformations (VMs), most of which associated with activating mutations in the endothelial cells (ECs) tyrosine kinase receptor TIE2, are characterized by dilated and immature veins with scarce smooth muscle cells (SMCs) coverage. However, the underlying mechanism of interaction between ECs and SMCs responsible for VMs has not been fully understood. Methods Here, we screened 5 patients with TIE2-L914F mutation who were diagnosed with VMs by SNP sequencing, and we compared the expression of platelet-derived growth factor beta (PDGFB) and α-SMA in TIE2 mutant veins and normal veins by immunohistochemistry. In vitro, we generated TIE2-L914F-expressing human umbilical vein endothelial cells (HUVECs) and performed BrdU, CCK-8, transwell and tube formation experiments on none-transfected and transfected ECs. Then we investigated the effects of rapamycin (RAPA) on cellular characteristics. Next we established a co-culture system and investigated the role of AKT/FOXO1/PDGFB in regulating cross-talking of mutant ECs and SMCs. Results VMs with TIE2-L914F mutation showed lower expression of PDGFB and α-SMA than normal veins. TIE2 mutant ECs revealed enhanced cell viability and motility, and decreased tube formation, whereas these phenotypes could be reversed by rapamycin. Mechanically, RAPA ameliorated the physiological function of mutant ECs by inhibiting AKT-mTOR pathway, but also facilitated the nuclear location of FOXO1 and the expression of PDGFB in mutant ECs, and then improved paracrine interactions between ECs and SMCs. Moreover, TIE2 mutant ECs strongly accelerated the transition of SMCs from contractile phenotype to synthetic phenotype, whereas RAPA could prevent the phenotype transition of SMCs. Conclusions Our data demonstrate a previously unknown mechanistic linkage of AKT-mTOR/FOXO1 pathway between mutant ECs and SMCs in modulating venous dysmorphogenesis, and AKT/FOXO1 axis might be a potential therapeutic target for the recovery of TIE2-mutation causing VMs. Video Abstract
Graphical abstract ![]()
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Affiliation(s)
- Yameng Si
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,The Affiliated Stomatological Hospital of Xuzhou Medical University, Xuzhou, China
| | - Jiadong Huang
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Xiang Li
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Yu Fu
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Rongyao Xu
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Yifei Du
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Jie Cheng
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China.,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China
| | - Hongbing Jiang
- Jiangsu Key Laboratory of Oral Diseases, Nanjing Medical University, 136 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China. .,Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Stomatology, Nanjing Medical University, Nanjing, China.
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Lee E, Jeon H, Ryu J, Kang C, Kim S, Park S, Kwon Y. Genetically encoded biosensors for the detection of rapamycin: toward the screening of agonists and antagonists. Analyst 2020; 145:5571-5577. [PMID: 32618311 DOI: 10.1039/d0an01116a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Biosensors are valuable tools for the rapid screening of biological targets with high sensitivity and specificity. It is important to screen biological events in their native context for pharmacological and toxicological applications. However, in vitro biosensors often require purified probes and targets for screening, thus providing limited information on the biological activities of targets in their native environment. To address this issue, we developed a cell-based sensing system that could detect a biologically active small molecule, rapamycin (Rapa). We designed a reporter system based on fluorescence translocation by signal peptide reconstitution. Herein, signal peptides are activated by conditional protein splicing without the need for refolding into a functional tertiary structure, thus eliminating false positives and negatives due to mere binding or misfolding. The developed biosensor demonstrated excellent sensitivity with a limit of detection of 0.1 nM, and it was able to screen the agonist and antagonist of Rapa. The developed cell-based sensing system could contribute to improving the screening system aimed to identify the natural mimetics of Rapa and potential drug candidates.
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Affiliation(s)
- Euiyeon Lee
- Department of Biomedical Engineering (BK21 plus), Dongguk University, Seoul 04620, Korea.
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Saxena S, Kumar S. Pharmacotherapy to gene editing: potential therapeutic approaches for Hutchinson-Gilford progeria syndrome. GeroScience 2020; 42:467-494. [PMID: 32048129 PMCID: PMC7205988 DOI: 10.1007/s11357-020-00167-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 02/04/2020] [Indexed: 12/11/2022] Open
Abstract
Hutchinson-Gilford progeria syndrome (HGPS), commonly called progeria, is an extremely rare disorder that affects only one child per four million births. It is characterized by accelerated aging in affected individuals leading to premature death at an average age of 14.5 years due to cardiovascular complications. The main cause of HGPS is a sporadic autosomal dominant point mutation in LMNA gene resulting in differently spliced lamin A protein known as progerin. Accumulation of progerin under nuclear lamina and activation of its downstream effectors cause perturbation in cellular morphology and physiology which leads to a systemic disorder that mainly impairs the cardiovascular system, bones, skin, and overall growth. Till now, no cure has been found for this catastrophic disorder; however, several therapeutic strategies are under development. The current review focuses on the overall progress in the field of therapeutic approaches for the management/cure of HGPS. We have also discussed the new disease models that have been developed for the study of this rare disorder. Moreover, we have highlighted the therapeutic application of extracellular vesicles derived from stem cells against aging and aging-related disorders and, therefore, suggest the same for the treatment of HGPS.
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Affiliation(s)
- Saurabh Saxena
- Department of Medical Laboratory Sciences, Lovely Professional University, Jalandhar - Delhi G.T. Road, Phagwara, Punjab, 144411, India.
| | - Sanjeev Kumar
- Faculty of Technology and Sciences, Lovely Professional University, Jalandhar - Delhi G.T. Road, Phagwara, Punjab, 144411, India
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Wang S, Wang M, Liu Y, Hu D, Gu L, Fei X, Zhang J. Effect of Rapamycin Microspheres in Sjögren Syndrome Dry Eye: Preparation and Outcomes. Ocul Immunol Inflamm 2018; 27:1357-1364. [PMID: 30273514 DOI: 10.1080/09273948.2018.1527369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 09/19/2018] [Accepted: 09/19/2018] [Indexed: 12/15/2022]
Abstract
Purpose: To prepare a drug delivery system of rapamycin poly-3-hydroxybutyrate-co-3-hydroxyvalerate microspheres (RPM) and analyze its effect on the eyes of a Sjögren's syndrome mouse model.Methods: RPM was generated using a solvent evaporation method, and observed under light and electron microscopy. No obesity diabetes (NOD) mice with Sjögren's syndrome were randomized into normal saline, empty microspheres, and RPM groups, with healthy Kunming mice as the controls. Dry eye signs were assessed using a slit lamp. Tear secretion, corneal fluorescein, keratoconjunctival rose bengal, and conjunctival impression cytology were recorded.Results: RPM was smooth and spherical, about 20-50 μm in diameter, without agglomeration or adhesion. Mice receiving RPM secreted more tears. And they had a normal corneal histology, exhibiting reduced corneal fluorescein, rose bengal staining, and conjunctival impression cytology.Conclusion: RPM improved the signs of dry eyes, improved tear secretion, decreased corneal endothelial cell injury, and improved histological damage of the cornea in NOD mice.
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Affiliation(s)
- Shasha Wang
- Department of Ophthalmology, Shanghai Jiaotong University Affiliated the First People's Hospital, Shanghai, P. R. China
- Department of Ophthalmology, Shanghai Jing 'an District ShiBei Hospital, Shanghai, P. R. China
| | - Meng Wang
- Department of Ophthalmology, Shanghai Jiaotong University Affiliated the First People's Hospital, Shanghai, P. R. China
| | - Yan Liu
- Department of Ophthalmology, Shanghai Jiaotong University Affiliated the First People's Hospital, Shanghai, P. R. China
| | - Daode Hu
- Department of Pharmacy, Shanghai Jiaotong University Affiliated the First People's Hospital, Shanghai, P. R. China
| | - Lei Gu
- Department of Scientific Research and Education, Branch of the First People's Hospital of Shanghai, Shanghai, P. R. China
| | - Xinfeng Fei
- Department of Ophthalmology, Branch of the First People's Hospital of Shanghai, Shanghai, P. R. China
| | - Jianhong Zhang
- Department of Ophthalmology, Branch of the First People's Hospital of Shanghai, Shanghai, P. R. China
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Yuan S, Wu Y, Wang Y, Chen J, Chu L. An Oncolytic Adenovirus Expressing SNORD44 and GAS5 Exhibits Antitumor Effect in Colorectal Cancer Cells. Hum Gene Ther 2017; 28:690-700. [PMID: 28530127 DOI: 10.1089/hum.2017.041] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
SNORD44 is a C/D box small nucleolar RNA, and exhibits low expression in breast cancer and head and neck squamous cell carcinoma tissues. Its host gene is growth arrest specific transcript 5 (GAS5), which is a long noncoding RNA. GAS5 is downregulated in colorectal cancer (CRC), and overexpression of GAS5 suppresses cell proliferation. However, the function of SNORD44 in CRC remains largely unknown, and the application of SNORD44 combined with GAS5 in CRC treatment has not been reported. In this study, the expression levels of SNORD44 and GAS5 were measured in CRC tissues by quantitative RT-PCR. The correlation between SNORD44 and GAS5 was evaluated by Pearson correlation analysis. An oncolytic adenovirus expressing SNORD44 and GAS5 (SPDD-UG) was constructed. The biological effects of SPDD-UG were investigated in CRC cell line SW620 and LS174T in vitro and in xenografts. The synergistic effect of rapamycin and SPDD-UG was explored in SW620 and LS174T cells and tumors. We demonstrated that SNORD44 expression level was markedly decreased in CRC tissues and positively correlated with GAS5 expression. SPDD-UG significantly inhibited SW620 and LS174T cell growth and induced cell apoptosis. Intratumoral injection of SPDD-UG significantly suppressed xenografts growth in nude mice. Moreover, the mechanistic target of rapamycin (mTOR) inhibitor, rapamycin, enhanced the antitumor effect through antagonizing the PI3K/Akt pathway activated by SPDD-UG. These results suggest that overexpression of SNORD44 and GAS5 by oncolytic adenovirus provides a promising method for CRC therapy.
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Affiliation(s)
- Sujing Yuan
- 1 Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, China
| | - Yu Wu
- 1 Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, China
| | - Yigang Wang
- 2 Xinyuan Institute of Medicine and Biotechnology, School of Life Sciences, Zhejiang Sci-Tech University , Hangzhou, China
| | - Jianhua Chen
- 3 State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai, China
| | - Liang Chu
- 1 Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, China
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Risk Assessment of Drug–Drug Interactions of Calcineurin Inhibitors Affecting Sirolimus Pharmacokinetics in Renal Transplant Patients. Ther Drug Monit 2016; 38:607-13. [DOI: 10.1097/ftd.0000000000000314] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Baroja-Mazo A, Revilla-Nuin B, Ramírez P, Pons JA. Immunosuppressive potency of mechanistic target of rapamycin inhibitors in solid-organ transplantation. World J Transplant 2016; 6:183-192. [PMID: 27011916 PMCID: PMC4801794 DOI: 10.5500/wjt.v6.i1.183] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 12/22/2015] [Accepted: 01/07/2016] [Indexed: 02/05/2023] Open
Abstract
Mammalian target of rapamycin, also known as mechanistic target of rapamycin (mTOR) is a protein kinase that belongs to the PI3K/AKT/mTOR signaling pathway, which is involved in several fundamental cellular functions such as cell growth, proliferation, and survival. This protein and its associated pathway have been implicated in cancer development and the regulation of immune responses, including the rejection response generated following allograft transplantation. Inhibitors of mTOR (mTORi) such as rapamycin and its derivative everolimus are potent immunosuppressive drugs that both maintain similar rates of efficacy and could optimize the renal function and diminish the side effects compared with calcineurin inhibitors. These drugs are used in solid-organ transplantationtoinduceimmunosuppression while also promoting the expansion of CD4+CD25+FOXP3+ regulatory T-cells that could favor a scenery of immunological tolerance. In this review, we describe the mechanisms by which inhibitors of mTOR induce suppression by regulation of these pathways at different levels of the immune response. In addition, we particularly emphasize about the main methods that are used to assess the potency of immunosuppressive drugs, highlighting the studies carried out about immunosuppressive potency of inhibitors of mTOR.
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13
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Temsirolimus as Base Immunosuppressant for a Recipient With Metastatic Renal Cancer: Adequate Immunosuppression and Oncological Control—Case Report. Transplant Proc 2014; 46:271-3. [DOI: 10.1016/j.transproceed.2013.08.106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2013] [Accepted: 08/16/2013] [Indexed: 02/06/2023]
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14
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PI3K-Akt signaling activates mTOR-mediated epileptogenesis in organotypic hippocampal culture model of post-traumatic epilepsy. J Neurosci 2013; 33:9056-67. [PMID: 23699517 DOI: 10.1523/jneurosci.3870-12.2013] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
mTOR is activated in epilepsy, but the mechanisms of mTOR activation in post-traumatic epileptogenesis are unknown. It is also not clear whether mTOR inhibition has an anti-epileptogenic, or merely anticonvulsive effect. The rat hippocampal organotypic culture model of post-traumatic epilepsy was used to study the effects of long-term (four weeks) inhibition of signaling pathways that interact with mTOR. Ictal activity was quantified by measurement of lactate production and electrical recordings, and cell death was quantified with lactate dehydrogenase (LDH) release measurements and Nissl-stained neuron counts. Lactate and LDH measurements were well correlated with electrographic activity and neuron counts, respectively. Inhibition of PI3K and Akt prevented activation of mTOR, and was as effective as inhibition of mTOR in reducing ictal activity and cell death. A dual inhibitor of PI3K and mTOR, NVP-BEZ235, was also effective. Inhibition of mTOR with rapamycin reduced axon sprouting. Late start of rapamycin treatment was effective in reducing epileptic activity and cell death, while early termination of rapamycin treatment did not result in increased epileptic activity or cell death. The conclusions of the study are as follows: (1) the organotypic hippocampal culture model of post-traumatic epilepsy comprises a rapid assay of anti-epileptogenic and neuroprotective activities and, in this model (2) mTOR activation depends on PI3K-Akt signaling, and (3) transient inhibition of mTOR has sustained effects on epilepsy.
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15
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Luo L, Sun Z, Luo G. Rapamycin is less fibrogenic than Cyclosporin A as demonstrated in a rat model of chronic allograft nephropathy. J Surg Res 2012; 179:e255-63. [PMID: 22480837 DOI: 10.1016/j.jss.2012.02.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 02/14/2012] [Accepted: 02/28/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND Cyclosporin A (CsA) is associated with significant chronic nephrotoxicity, which typically manifests as renal fibrosis. In contrast, rapamycin (RAPA) has been shown to inhibit fibrosis. This study sought to determine the effect of CsA and RAPA on the expression of connective tissue growth factor (CTGF) and E-cadherin in a rat kidney model of chronic allograft nephropathy. MATERIALS AND METHODS Left renal grafts from male Fisher (F344, RT1(1v1)) rats were orthotopically transplanted into Lewis (LEW, RT1(1)) rats. After transplantation, all recipients were given CsA 10 mg/kg(-1) d(-1) for 10 d and divided into three groups (n = 9/group): (1) vehicle, administered orally; (2) CsA, 6 mg/kg(-1) d(-1); (3) RAPA, 0.8 mg/kg(-1) d(-1). At 4, 8, and 12 wk posttransplantation, the kidney allografts were harvested and serum creatinine levels were measured. Connective tissue growth factor expression was determined using real-time polymerase chain reaction and Western blot. Kidney allografts sections also underwent hematoxylin-eosin and Masson trichrome staining, in addition to CTGF and E-cadherin immunostaining. RESULTS The serum creatinine levels were increased at 8 and 12 wk posttransplantation and were significantly lower in the RAPA group (P < 0.05). The Banff score also showed a significant decrease at 4, 8, and 12 wk (P < 0.05). CTGF messenger ribonucleic acid and protein levels were significantly lower in the RAPA group (P < 0.05), whereas E-cadherin expression was higher in the RAPA group at 4, 8, and 12 wk (P < 0.05). Masson's trichrome staining showed a significant decrease in collagen deposition at 8 and 12 wk after RAPA treatment. CONCLUSION RAPA can ameliorate fibrogenesis in kidney allografts by inhibiting epithelial-mesenchymal transition process, whereas CsA did not have this effect.
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Affiliation(s)
- Lei Luo
- Department of Research and Education, Guizhou Province People's Hospital, Guiyang, China
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16
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Behnke-Hall K, Bauer J, Thul J, Akintuerk H, Reitz K, Bauer A, Schranz D. Renal function in children with heart transplantation after switching to CNI-free immunosuppression with everolimus. Pediatr Transplant 2011; 15:784-9. [PMID: 21883744 DOI: 10.1111/j.1399-3046.2011.01550.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Renal impairment because of CNI contributes to long-term morbidity. Therefore, CNI avoiding or sparing treatment strategies are important. In this article, we describe the results of a CNI-free treatment protocol with regard to recovery of renal function. Twenty-eight patients with heart transplantation were switched from CNI regimen to everolimus and mycophenolate, when cGFR was <75 mL/min/1.73 m(2). In all patients, CNI was stopped, when everolimus trough levels of 5-8 ng/L were achieved. Serum creatinine and cGFR were determined before and after 6 and 12 months. Median serum creatinine decreased from 1.2 mg/dL (range 0.7-3.7) before everolimus to 1.0 (range 0.6-1.8) and 1.0 (range 0.5-1.9) mg/dL after 6 and 12 months. Median cGFR was 47.81 (range 18.3-72.6) mL/min/1.73 m(2) before everolimus and 63.1 (range 37.8-108.7) mL/min/1.73 m(2) at six months and 64.8 (range 37.7-106.6) mL/min/1.73 m(2) after 12 months. All changes from baseline to six and 12 months were statistically significant (p < 0.05). Adverse events were infections (n = 3) and rejections (n = 3). Therapy was discontinued in four patients. Conversion to CNI-free immunosuppression resulted in significant improvements of renal function within six months of CNI withdrawal. Side effects are common. However, more studies are required to demonstrate the effectiveness in children.
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17
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Fischer RT, Turnquist HR, Wang Z, Beer-Stolz D, Thomson AW. Rapamycin-conditioned, alloantigen-pulsed myeloid dendritic cells present donor MHC class I/peptide via the semi-direct pathway and inhibit survival of antigen-specific CD8(+) T cells in vitro and in vivo. Transpl Immunol 2011; 25:20-6. [PMID: 21596137 DOI: 10.1016/j.trim.2011.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 04/29/2011] [Accepted: 05/02/2011] [Indexed: 11/26/2022]
Abstract
Dendritic cells (DC) are "professional" bone marrow-derived antigen (Ag)-presenting cells of interest both as therapeutic targets and potential cellular vaccines due to their ability to regulate innate and adaptive immunity. Harnessing the inherent tolerogenicity of DC is a promising and incompletely explored approach to the prevention of allograft rejection. Previously, we and others have reported the ability of pharmacologically-modified DC, that resist maturation, to inhibit CD4(+) T cell responses and prolong allograft survival. Here we evaluated the ability of murine myeloid DC conditioned with the immunosuppressive pro-drug rapamycin (RAPA) to acquire and directly present alloAg to syngeneic CD8(+) T cells. RAPA-conditioned DC (RAPA-DC) pulsed with allogeneic splenocyte lysate acquired and expressed donor MHC class I and enhanced the apoptotic death of directly-reactive donor Ag-specific CD8(+) T cells in vitro. Moreover, following their adoptive transfer, they reduced the survival of these T cells in vivo. The ability of RAPA-DC to inhibit the survival of alloAg-specific CD8(+) T cells provides a potential mechanism by which host-derived DC may act as negative regulators of T cell alloreactivity and support donor-specific unresponsiveness. Adoptive cell therapy with alloAg-pulsed RAPA-DC may offer an effective approach to suppression of alloimmunity, with reduced dependence on systemic immunosuppression.
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Affiliation(s)
- Ryan T Fischer
- Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15238, USA.
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18
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Álvarez-García Ó, García-López E, Loredo V, Gil-Peña H, Rodríguez-Suárez J, Ordóñez FÁ, Carbajo-Pérez E, Santos F. Rapamycin induces growth retardation by disrupting angiogenesis in the growth plate. Kidney Int 2010; 78:561-8. [DOI: 10.1038/ki.2010.173] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Jacques J, Dickson Z, Carrier P, Essig M, Guillaudeau A, Lacour C, Bocquentin F, Aldigier JC, Rerolle JP. Severe sirolimus-induced acute hepatitis in a renal transplant recipient. Transpl Int 2010; 23:967-70. [PMID: 20497403 DOI: 10.1111/j.1432-2277.2010.01100.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Sirolimus is currently used as an immunosuppressive agent in kidney transplantation due to its lack of nephrotoxicity and antiproliferative properties. However, a large number of side effects has been described with the use of m-Tor inhibitors. Most are reversible when treatment is withdrawn. Hepatotoxicity is one of these side effects, considered as a benign condition and resulting generally in a transitory and small increase in transaminase levels. We report here, to the best of our knowledge, the first case of severe sirolimus-induced acute hepatitis confirmed by liver biopsy, in a renal transplant recipient. This condition was completely cured in few weeks after sirolimus withdrawal.
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Affiliation(s)
- Jeremie Jacques
- Department of Hepatogastroenterology, CHU Dupuytren, Limoges, France
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20
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Abstract
The Edmonton protocol was undoubtedly a major step forward in the history of islet transplantation. Its immunosuppression regimen was largely based on the mTOR inhibitor rapamycin (sirolimus), which remains the most frequently used immunosuppressive drug in clinical islet transplant protocols. As time reveals the somewhat disappointing long-term results achieved with the Edmonton protocol, a number of publications have appeared addressing the potential beneficial or deleterious role of rapamycin on islet cell engraftment, function survival and regeneration, as well as on its side-effects in human subjects. This paper reviews the sometimes contradictory evidence on the impact of rapamycin in islet transplantation.
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Affiliation(s)
- Thierry Berney
- Division of Transplantation and Visceral Surgery, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland.
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21
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Turnquist HR, Raimondi G, Zahorchak AF, Fischer RT, Wang Z, Thomson AW. Rapamycin-conditioned dendritic cells are poor stimulators of allogeneic CD4+ T cells, but enrich for antigen-specific Foxp3+ T regulatory cells and promote organ transplant tolerance. THE JOURNAL OF IMMUNOLOGY 2007; 178:7018-31. [PMID: 17513751 DOI: 10.4049/jimmunol.178.11.7018] [Citation(s) in RCA: 340] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The ability of dendritic cells (DC) to regulate Ag-specific immune responses via their influence on T regulatory cells (Treg) may be key to their potential as therapeutic tools or targets for the promotion/restoration of tolerance. In this report, we describe the ability of maturation-resistant, rapamycin (RAPA)-conditioned DC, which are markedly impaired in Foxp3(-) T cell allostimulatory capacity, to favor the stimulation of murine alloantigen-specific CD4(+)CD25(+)Foxp3(+) Treg. This was distinct from control DC, especially following CD40 ligation, which potently expanded non-Treg. RAPA-DC-stimulated Treg were superior alloantigen-specific suppressors of T effector responses compared with those stimulated by control DC. Supporting the ability of RAPA to target effector T and B cells, but permit the proliferation and suppressive function of Treg, an infusion of recipient-derived alloantigen-pulsed RAPA-DC followed by a short postoperative course of low-dose RAPA promoted indefinite (>100 day) heart graft survival. This was associated with graft infiltration by CD4(+)Foxp3(+) Treg and the absence of transplant vasculopathy. The adoptive transfer of CD4(+) T cells from animals with long-surviving grafts conferred resistance to rejection. These novel findings demonstrate that, whereas maturation resistance does not impair the capacity of RAPA-DC to modulate Treg, it profoundly impairs their ability to expand T effector cells. A demonstration of this mechanism endorses their potential as tolerance-promoting cellular vaccines.
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Affiliation(s)
- Heth R Turnquist
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
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22
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Mehrabi A, Fonouni H, Kashfi A, Schmied BM, Morath C, Sadeghi M, Schemmer P, Encke J, Sauer P, Zeier M, Weitz J, Büchler MW, Schmidt J. The role and value of sirolimus administration in kidney and liver transplantation. Clin Transplant 2007; 20 Suppl 17:30-43. [PMID: 17100699 DOI: 10.1111/j.1399-0012.2006.00598.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Enormous advancements in visceral transplantation have led to significant improvements in the quality of life of patients. However, despite these developments, the average graft half-life after transplantation has remained almost unchanged and chronic rejection is still considered a major problem. In this regard, more concerns have shifted to factors influencing long-term graft survival, patient survival, and quality of life. To achieve this goal, detrimental effects of immunosuppressive (IS) agents, which have deleterious influence on the quality of life and/or patient survival, should be reduced. In the course of recent years, the transplant community has worked on reducing these side effects by developing new ISs, employing new combination regimens, or finding and adjusting optimal dosages and blood level concentrations. Among the IS agents, the antifungal, antitumoral and IS activity of mammalian target of rapamycin (mTOR) inhibitors without nephrotoxicity, have received special attention regarding this new class of IS. Sirolimus (SRL), as the first member of mTOR inhibitors, has been utilized in many clinical trials with respect to its benefit-risk assessment. In our review, the clinical evolution of SRL, as well as the evidence-based clinical benefits of SRL in kidney and liver transplantation (KTx, LTx), are summarized. Various studies of SRL in KTx and LTx have shown that combination therapy with SRL will enrich the variety of IS modalities. It also can be regarded as a safe base therapy to which other necessary drugs can be added. In addition to the enhanced acute rejection prophylaxis, and in contrast to the calcineurin inhibitors (CNI) and steroids, this drug solely does not have common side effects such as nephrotoxicity, neurotoxicity, diabetes mellitus and hypertension. Moreover, this agent might diminish vasculopathic processes that mediate chronic allograft nephropathy (CAN). Therefore, by reducing the likelihood of CAN it can decrease the rate of long-term organ failure. One possibly desirable characteristic of SRL is its antiproliferative effect, which could provoke antitumoral or antiatherogenic activity following transplantation. Despite all promising impacts of SRL in organ transplantation, there are some concerns regarding the adverse effects of this drug, for instance dyslipidemia, pneumonitis and wound healing problems. However, the majority of these side effects can be reduced or ceased by careful dose adjustments and correct timing of use. In conclusion, after a decade of both in vivo and in vitro studies on SRL, it can be advocated that SRL is a promising, potent and effective IS agent as it reduces the rate of acute rejection episodes in de novo transplants. It could improve the quality of life, graft and patient survival rate, and achieve excellent outcomes with few adverse effects when wisely used in combination with other immunosuppressants.
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Affiliation(s)
- A Mehrabi
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany.
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23
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Basu A, Falcone JL, Tan HP, Hassan D, Dvorchik I, Bahri K, Thai N, Randhawa PS, Marcos A, Starzl TE, Shapiro R. Chronic allograft nephropathy score before sirolimus rescue predicts allograft function in renal transplant patients. Transplant Proc 2007; 39:94-8. [PMID: 17275482 PMCID: PMC2963426 DOI: 10.1016/j.transproceed.2006.10.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2006] [Indexed: 12/21/2022]
Abstract
Chronic allograft nephropathy (CAN) is a major indication for initiation of sirolimus (SRL) in renal transplantation (TX) to prevent deterioration of renal function. We evaluated whether the CAN score at time of sirolimus rescue (SRL-R) predicts renal allograft function. CAN score is the sum of the following 4 categories: glomerulopathy (cg, 0-3), interstitial fibrosis (ci, 0-3), tubular atrophy (ct, 0-3), and vasculopathy (cv, 0-3). This is a retrospective cohort study of renal transplant recipients from July 2001 to March 2004. Immunosuppression consisted of preconditioning with rabbit anti-thymocyte globulin or alemtuzumab and maintenance with tacrolimus (TAC) monotherapy with spaced weaning, if applicable, SRL-R was achieved by conversion from TAC, or by addition to reduced doses of TAC. Ninety patients received SRL. Thirty-three of these patients met the inclusion criteria of the following: (1) receipt of SRL for >6 months, and (2) follow-up of > or =6 months. There were 16 patients in the low-CAN (0-4) group and 17 patients in the high-CAN (>4) group. Cockcroft-Gault (C-G) glomerular filtration rate (GFR) was calculated at SRL-R and at 1, 3, 6, and 12 months. The DeltaGFR was significantly better in the low-CAN group at 1, 3, and 6 months. A trend toward an improved DeltaGFR was present at 12 months in the low-CAN group (P = .16). CAN scoring at the time of SRL-R predicts recovery of renal allograft function (as measured using DeltaGFR), and should be used in preference to biochemical markers (Cr and C-G GFR), which may not be reliable predictors.
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Affiliation(s)
- A Basu
- Thomas E Starzl Transplantation Institute, Pittsburgh, PA 15213, USA
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24
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Pedroso SL, Martins LS, Sousa S, Reis A, Dias L, Henriques AC, Sarmento AM, Cabrita A. Pulmonary alveolar proteinosis ? a rare pulmonary toxicity of sirolimus. Transpl Int 2007; 20:291-6. [PMID: 17291222 DOI: 10.1111/j.1432-2277.2006.00408.x] [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: 11/28/2022]
Abstract
The aim of our paper is to describe an unusual pulmonary toxicity of sirolimus (SRL) in a kidney transplant recipient. We present a 34-year-old woman with a second renal transplantation, complicated with steroid-resistant acute rejection and chronic allograft dysfunction. Two years after initiating SRL, she presented complaints of progressive dyspnoea, nonproductive cough, chest pain and low-grade fever of 1 month duration. She had chronic allograft nephropathy and slight elevation of lactic dehydrogenase levels. After exclusion of common reasons of this condition, a computed tomography (CT) of the thorax and bronchoscopy was performed, revealing ground-glass opacification with polygonal shapes on CT and an opaque appearance with numerous macrophages on bronchoalveolar lavage. The alveolar macrophages stained positive by Periodic acid-Schiff. Diagnosis of pulmonary alveolar proteinosis (PAP) was made and drug-induced toxicity was suspected. SRL was withdrawn with marked improvement in the patients' clinical and radiological status. PAP resolved within 3 months without further therapy. PAP is a very rare complication of SRL therapy with only a few cases described. Withdrawal of SRL with conversion to another immunosuppressant seems to be an appropriate procedure in this condition.
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Affiliation(s)
- Sofia L Pedroso
- Nephrology Department, Hospital Geral de Santo António, Porto, Portugal.
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25
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Schiff J, Cole E, Cantarovich M. Therapeutic monitoring of calcineurin inhibitors for the nephrologist. Clin J Am Soc Nephrol 2007; 2:374-84. [PMID: 17699437 DOI: 10.2215/cjn.03791106] [Citation(s) in RCA: 189] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The calcineurin inhibitors (CNI) cyclosporine and tacrolimus remain the backbone of immunosuppression for most kidney transplant recipients. Despite many years of experience, protocols that optimize efficacy with minimal toxicity remain a subject of debate. Nevertheless, studies of the pharmacokinetic properties of the CNI, particularly cyclosporine, have led to improved dosing strategies. The purpose of this article is to review the current understanding of CNI pharmacokinetics and its relevance to proper dosing and monitoring of these medications. This article also reviews the trials that have helped to define the optimal dosages and discusses the effect of adjunctive immunosuppressive agents on CNI pharmacokinetics and dosing.
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Affiliation(s)
- Jeffrey Schiff
- Division of Nephrology, University Health Network, Toronto General Hospital, Toronto, Ontario, Canada
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26
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Lischke R, Simonek J, Matousovic K, Stolz AJ, Schützner J, Vojácek J, Burkert J, Davidová R, Pafko P. Initial Single-Center Experience With Sirolimus After Lung Transplantation. Transplant Proc 2006; 38:3006-11. [PMID: 17112886 DOI: 10.1016/j.transproceed.2006.08.105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND Standard immunosuppression after lung transplantation includes calcineurin inhibitors, mycophenolate mofetil, and steroids. Long-term survivors of lung transplantation are often confronted with chronic kidney disease, by definition related to the intake of calcineurin inhibitors. Sirolimus has been increasingly proposed as an alternative immunosuppressive agent due to its absence of nephrotoxicity, which could be used in selected patients. METHODS We prospectively administered sirolimus as an alternative to calcineurin inhibitors in 10 lung transplantation recipients with persistent drug nephrotoxicity. They were switched from tacrolimus to sirolimus. Four patients also had bronchiolitis obliterans syndrome. The conversion scheme consisted of an immediate stop of tacrolimus and an 6 to 8-mg loading dose of sirolimus, followed by 4 mg/d. After 5 days, the sirolimus dose was adjusted to maintain trough levels between 12 and 18 ng/mL or 6 and 12 ng/mL for combined sirolimus and tacrolimus. Patients were monitored for renal and graft function as well as clinical status. RESULTS A significant decrease in creatinine was observed after 1 week of treatment (P = .011). Azotemia decreased after 1 month, remaining stable (P < .01). Pulmonary function tests did not show significant modification from before sirolimus, inception in patients with or without bronchiolitis obliterans syndrome. There were seven infections. One patient died of complications related to bronchiolitis obliterans. CONCLUSION Sirolimus was a useful alternative immunosuppressant, allowing significant tacrolimus withdrawal in transplant recipients with renal impairment. Sirolimus administration allowed recovery of renal function with low morbidity; it was useful for rescue of chronic renal impairment after lung transplantation.
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Affiliation(s)
- R Lischke
- 3rd Department of Surgery, Thoracic and Lung Transplantation Division, University Hospital Motol, Prague, Czech Republic.
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27
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Shihab FS, Bennett WM, Yi H, Andoh TF. Effect of cyclosporine and sirolimus on the expression of connective tissue growth factor in rat experimental chronic nephrotoxicity. Am J Nephrol 2006; 26:400-7. [PMID: 16926534 DOI: 10.1159/000095300] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Accepted: 07/19/2006] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS Connective tissue growth factor (CTGF) is a pro-fibrotic growth factor that acts downstream of transforming growth factor (TGF)-beta. However, CTGF regulation remains unknown. We tried to determine the effect of two commonly used immunosuppressants, cyclosporine (CsA) and sirolimus (SRL), on CTGF expression in a model of chronic nephrotoxicity. METHODS Adult Sprague-Dawley rats kept on a low-salt diet were treated daily for 4 weeks with vehicle (VH), SRL (0.3 mg/kg), CsA5 (5 mg/kg), CsA10 (10 mg/kg) or both CsA5 and SRL. CTGF and TGF-beta1 expressions were evaluated by Northern blot. Functional and histologic parameters in addition to number of apoptotic cells were determined. RESULTS At 28 days, both CsA doses were capable of inhibiting CTGF mRNA expression to levels similar to control. On the other hand, SRL increased CTGF expression by 3.5-fold. However, addition of CsA to SRL completely reversed that trend and returned levels to control. The results were different for TGF-beta1, which was increased by both CsA and SRL and to a greater extent by the drug combination. CONCLUSION Unlike TGF-beta, CTGF does not seem to play an important role in CsA-induced chronic nephrotoxicity. In addition, calcineurin-dependent pathways are likely involved in CTGF regulation.
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Affiliation(s)
- Fuad S Shihab
- Division of Nephrology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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Abstract
Oral contraceptives, androgenic agents, progestins and gonadotropin-releasing hormone analogues have all been successfully used in the treatment of endometriosis. However, none of these drugs can eradicate the disease. It is widely accepted that the growth of newly formed blood vessels is essential for the establishment and growth of endometriotic lesions; therefore, inhibition of angiogenesis may offer a new option for treatment of this disorder. In this paper, we reviewed anti-vascular endothelial growth factor agents and other angiostatic drugs (i.e., TNP470, endostatin, anginex, rapamycin) that have been studied in laboratory and animal models of endometriosis. Although preliminary results are interesting, further investigations are required before clinical trials can be planned in humans.
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Affiliation(s)
- S Ferrero
- Department of Obstetrics and Gynaecology, San Martino Hospital and University of Genoa, Genoa, Italy.
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Höcker B, Feneberg R, Köpf S, Weber LT, Waldherr R, Wühl E, Tönshoff B. SRL-based immunosuppression vs. CNI minimization in pediatric renal transplant recipients with chronic CNI nephrotoxicity. Pediatr Transplant 2006; 10:593-601. [PMID: 16856996 DOI: 10.1111/j.1399-3046.2006.00526.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Because calcineurin inhibitor (CNI)-induced nephrotoxicity contributes significantly to late renal allograft loss, sirolimus (SRL)-based, CNI-free maintenance immunosuppression has been advocated, but data in the pediatric population are scarce. We therefore analyzed the efficacy and safety of an SRL-based immunosuppressive regimen plus mycophenolate mofetil (MMF) and corticosteroids vs. CNI minimization (mean dose reduction by 39%) plus MMF and corticosteroids in 19 pediatric recipients with biopsy-proven CNI-induced nephrotoxicity in a single-center case-control study. In the SRL group, we observed, one yr after study entry, an improvement of glomerular filtration rate (GFR) by 10.3 +/- 3.0 mL/min/1.73 m2 (p < 0.05 vs. baseline) in seven of 10 patients and a stabilization in the remaining three, while in the CNI minimization group GFR improved by 17.7 +/- 7.1 mL/min/1.73 m2 (p < 0.05) in six of nine recipients and stabilized in the remaining three. No patient in either group experienced an acute rejection episode. The main adverse event under SRL therapy was a transient hyperlipidemia in 70% of patients. In pediatric renal transplant recipients with declining graft function because of CNI-induced nephrotoxicity, CNI withdrawal and switch to SRL-based therapy or CNI minimization are associated with a comparable improvement of GFR after 12 months of observation.
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Affiliation(s)
- Britta Höcker
- Division of Pediatric Nephrology, University Children's Hospital Heidelberg, Im Neuenheimer Feld, Heidelberg, Germany
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Garcia CD, Bittencourt VB, Alves AB, Garcia VD, Tumelero A, Antonello JS, Malheiros D. Conversion to Sirolimus in Pediatric Renal Transplantation Recipients. Transplant Proc 2006; 38:1901-3. [PMID: 16908317 DOI: 10.1016/j.transproceed.2006.06.063] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
We retrospectively evaluated the efficacy and safety of sirolimus (SRL) in 16 pediatric renal transplant recipients, who were 9.4 +/- 4.1 years of age when they first received SRL. The indications for SRL therapy were rescue from steroid-resistant acute rejection (31.3%), neoplasia (31.3%), diabetes (12.5%), polyomavirus-associated nephropathy (6.3%), chronic allograft dysfunction (6.3%), calcineurin inhibitor nephrotoxicity (6.3%), and hemolytic uremic syndrome (6.3%). Mean follow-up after the switch to SRL was 17.7 +/- 15 months. The final immunosuppression was CNI + SRL + prednisone (PRED) in five patients, SRL + PRED in six, SRL + mycophenolate mofetil (MMF) + PRED in four, and SRL + MMF in one. The use of SRL in these selected pediatric renal recipients was successful, except when creatinine was high at the moment of conversion. Further studies are necessary to assess the beneficial outcomes versus adverse events among the pediatric transplant population receiving SRL for immunosuppression.
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Affiliation(s)
- C D Garcia
- Santo Antônio Children's Hospital, Santa Casa Porto Alegre Hospital Complex, School of Medical Sciences, Correa Lima 1493, Porto Alegre, 90850-250 Brazil.
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Wu MS, Hung CC, Chang CT. Renal calcium handling after rapamycin conversion in chronic allograft dysfunction. Transpl Int 2006; 19:140-5. [PMID: 16441363 DOI: 10.1111/j.1432-2277.2005.00251.x] [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] [Indexed: 12/30/2022]
Abstract
To study the effect of rapamycin on calcium balance, we conducted a prospective study on transplant recipients. The patients were converted to rapamycin and observed for 6 months (C). Urinary Ca and P, ALK-p, Ca, P, and intact parathyroid hormone (iPTH) were examined before and 6 months after conversion. A nonconversion group (N) was found for comparison. Sixteen patients entered the study. There were increases of ALK-p (C: 67.4 +/- 32.9 to 79.6 +/- 37.0*; N: 67.3 +/- 25.1 to 67.8 +/- 14.7 IU) (*P < 0.05), Ca(2+) (C: 8.7 +/- 0.3 to 9.5 +/- 0.2*; N: 8.8 +/- 0.4 to 8.7 +/- 0.5 mg/dl), urinary P excretion (C: 287.6 +/- 257.1 to 439.4 +/- 260.9*; N: 233.9 +/- 117.2 to 264.8 +/- 143.4 mg/day) and iPTH (C: 133.7 +/- 149.6 to 200.6 +/- 171.5*; N: 128.4 +/- 57.1 to 136.3 +/- 40.4 pg/ml). Serum P (C: 5.3 +/- 1.4 to 3.6 +/- 0.6*; N: 5.2 +/- 0.8 to 5.1 +/- 0.9 mg/dl) and urinary Ca(2+) (C: 93.9 +/- 52.6 to 31.8 +/- 45.1*; N: 84.6 +/- 38.3 to 75.9 +/- 38.4 mg/day) were decrease. Rapamycin was associated with decreased urinary Ca(2+) and increased P excretion. The alteration might come from the increased parathyroid hormone.
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Affiliation(s)
- Mai-Szu Wu
- Department of Nephrology, School of Medicine, Chang-Gung University, Chang Gung Memorial Hospital, Keelung, Taiwan.
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Augustine JJ, Chang PC, Knauss TC, Aeder MI, Bodziak KA, Schulak JA, Hricik DE. Improved Renal Function after Conversion from Tacrolimus/Sirolimus to Tacrolimus/Mycophenolate Mofetil in Kidney Transplant Recipients. Transplantation 2006; 81:1004-9. [PMID: 16612276 DOI: 10.1097/01.tp.0000202880.78509.b4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND There is limited data on the potential nephrotoxicity of sirolimus (SRL) and tacrolimus (TAC) in combination. METHODS We reviewed the course of 97 kidney transplant patients treated with SRL and reduced-dose TAC. Conversion from SRL to mycophenolate mofetil (MMF) was prescribed in a minority (n = 19) for various nonrenal side effects. We compared outcomes of converted patients to those remaining on TAC/SRL (n = 78). RESULTS TAC levels were increased in converters (P = 0.009). Rejection rates were similar between groups over 18 months (21% vs. 16%, p = ns). Serum creatinine (Cr) and MDRD glomerular filtration rate (GFR) were similar between groups at nadir and six-months, but at 18 months the percent change from six-month Cr was +17% in non-converters vs. -10% in converters (P = 0.004 for the difference). The difference in GFR between groups at 18 months was also significant (P = 0.01). By multivariate analysis, only conversion to MMF was associated with a greater percent change in Cr from 6 to 18 months (P = 0.015). Conversion to MMF also correlated with higher GFR at 18 months independent of rejection, delayed graft function, and ethnicity. CONCLUSIONS Conversion from TAC/SRL to TAC/MMF led to improved renal function despite increased TAC exposure after conversion.
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Affiliation(s)
- Joshua J Augustine
- Division of Nephrology, University Hospitals of Cleveland, OH 44106, USA.
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Sarbassov DD, Ali SM, Sengupta S, Sheen JH, Hsu PP, Bagley AF, Markhard AL, Sabatini DM. Prolonged Rapamycin Treatment Inhibits mTORC2 Assembly and Akt/PKB. Mol Cell 2006; 22:159-68. [PMID: 16603397 DOI: 10.1016/j.molcel.2006.03.029] [Citation(s) in RCA: 2057] [Impact Index Per Article: 114.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2006] [Revised: 03/24/2006] [Accepted: 03/28/2006] [Indexed: 12/13/2022]
Abstract
The drug rapamycin has important uses in oncology, cardiology, and transplantation medicine, but its clinically relevant molecular effects are not understood. When bound to FKBP12, rapamycin interacts with and inhibits the kinase activity of a multiprotein complex composed of mTOR, mLST8, and raptor (mTORC1). The distinct complex of mTOR, mLST8, and rictor (mTORC2) does not interact with FKBP12-rapamycin and is not thought to be rapamycin sensitive. mTORC2 phosphorylates and activates Akt/PKB, a key regulator of cell survival. Here we show that rapamycin inhibits the assembly of mTORC2 and that, in many cell types, prolonged rapamycin treatment reduces the levels of mTORC2 below those needed to maintain Akt/PKB signaling. The proapoptotic and antitumor effects of rapamycin are suppressed in cells expressing an Akt/PKB mutant that is rapamycin resistant. Our work describes an unforeseen mechanism of action for rapamycin that suggests it can be used to inhibit Akt/PKB in certain cell types.
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Affiliation(s)
- Dos D Sarbassov
- Whitehead Institute for Biomedical Research and Massachusetts Institute of Technology, Department of Biology, Nine Cambridge Center, Cambridge, Massachusetts 02142, USA
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Kim MJ, Mayr M, Pechula M, Steiger J, Dickenmann M. Marked erythrocyte microcytosis under primary immunosuppression with sirolimus. Transpl Int 2006; 19:12-8. [PMID: 16359372 DOI: 10.1111/j.1432-2277.2005.00190.x] [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: 11/26/2022]
Abstract
The preliminary observation of marked erythrocyte microcytosis in patients treated with sirolimus (SRL) and mycophenolate mofetil (MMF) has been evaluated as part of a prospective study comparing SRL and cyclosporin A (CsA) as a primary immunosuppressant. Normal risk de novo kidney recipients were randomized either to SRL or to CsA. Additional immunosuppressants consisted of MMF and prednisone. In patients with erythrocyte microcytosis, iron deficiency was excluded by measuring serum ferritin and transferrin saturation rate. Fifty-nine patients (30 in SRL and 29 in CsA) were included. Mean corpuscular volume (MCV) (fl) on day 7 was 91.7 +/- 4.8 in SRL group versus 91.4 +/- 4.2 in CsA group (P = 0.77), whereas mean MCV on day 183 post-transplant was 78.5 +/- 3.8 in SRL group versus 88.4 +/- 3.4 in CsA group (P < 0.0001). Hemoglobin concentration (g/dl) was not significantly different. Only two patients in SRL group presented decreased transferrin saturation rate. Marked erythrocyte microcytosis without persistent anemia was observed in patients treated with SRL and MMF.
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Affiliation(s)
- Min-Jeong Kim
- Division of Transplantation Immunology and Nephrology, University Hospital, Basel, Switzerland.
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Niemczyk M, Wyzgał J, Perkowska A, Porowski D, Paczek L. Sirolimus-associated hepatotoxicity in the kidney graft recipient. Transpl Int 2005; 18:1302-3. [PMID: 16221163 DOI: 10.1111/j.1432-2277.2005.00210.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The aim of our paper was to describe hepatotoxicity of sirolimus (SRL) in a kidney graft recipient. We report the case of a 30-year-old male after kidney transplantation, treated with steroids, cyclosporin A and SRL, with steroid-resistant acute rejection in anamnesis. At 16th month after transplantation, elevation of serum aminotransfereases was observed. After exclusion of common reasons of this condition, liver biopsy was performed. Nonspecific changes were observed, with probability of drug-induced injury. SRL was changed to mycophenolate mofetil, which was followed by quick normalization of serum aminotransferase levels. Hepatoxicity is a rare complication of SRL therapy and may be connected with some diagnostic and/or therapeutic problems. Conversion to another immunosuppressant seems to be an appropriate procedure in this condition.
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Affiliation(s)
- Mariusz Niemczyk
- Department of Immunology, Transplant Medicine and Internal Diseases, Transplantation Institute, Medical University of Warsaw, Warsaw, Poland.
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Morales JM, Dominguez-Gil B. Cardiovascular risk profile with the new immunosuppressive combinations after renal transplantation. J Hypertens 2005; 23:1609-16. [PMID: 16093902 DOI: 10.1097/01.hjh.0000180159.81640.2f] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cardiovascular disease remains the main cause of death among kidney transplant patients. Cardiovascular risk burden already present at the moment of transplantation is substantially worsened by chronic use of immunosuppressants. On the other hand, chronic allograft nephropathy, a clinical-pathological result of immunological and non-immunological damage of the graft, is the main cause of graft loss in the long-term. Among the non-immunological factors contributing to the development of chronic allograft nephropathy, cardiovascular risk factors also seem to play a role. In the present review, we analyse the impact of the different immunosuppressive medications on cardiovascular risk factors after renal transplantation, including renal function.
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Affiliation(s)
- José M Morales
- Renal Transplant Unit, Nephrology Department, Hospital 12 de Octubre, Carretera de Andalucia Km 5,400, 28041 Madrid, Spain
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Andres A, Toso C, Morel P, Demuylder-Mischler S, Bosco D, Baertschiger R, Pernin N, Bucher P, Majno PE, Bühler LH, Berney T. Impairment of renal function after islet transplant alone or islet-after-kidney transplantation using a sirolimus/tacrolimus-based immunosuppressive regimen. Transpl Int 2005; 18:1226-30. [PMID: 16221151 DOI: 10.1111/j.1432-2277.2005.00194.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The immunosuppressive (IS) regimen based on sirolimus/low-dose tacrolimus is considered a major determinant of success of the Edmonton protocol. This regimen is generally considered safe or even protective for the kidney. Herein, we analyzed the impact of the sirolimus/low-dose tacrolimus combination on kidney function. The medical charts of islet transplant recipients with at least 6 months follow up were reviewed. There were five islet-after-kidney and five islet transplantation alone patients. Serum creatinin, albuminuria, metabolic control markers and graft function were analyzed. Impairment of kidney function was observed in six of 10 patients. Neither metabolic markers nor IS drugs levels were significantly associated with the decrease of kidney function. Although a specific etiology was not identified, some subsets of patients presented a higher risk for decline of kidney function. Low creatinin clearance, albuminuria and long-established kidney graft were associated with poorer outcome.
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Affiliation(s)
- Axel Andres
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
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Maasilta PK, Vainikka TLS, Alho HS, Salminen US. Immune cells in a heterotopic lamb-to-pig bronchial xenograft model. Transpl Int 2005; 18:1100-8. [PMID: 16101731 DOI: 10.1111/j.1432-2277.2005.00192.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We developed our porcine model to elucidate the cellular rejection mechanisms of xenografts. Bronchial segments from a donor lamb were implanted into domestic pigs. The immunosuppressive regimens consisted of no immusuppression, or of daily oral cyclosporine A (CsA) 15 mg/kg, or of everolimus, 1.5 mg/kg, or of both. Implants were serially harvested during 17 days. Epithelial damage and obliteration were graded histologically, followed by a count of CD4+, CD8+, MHC class II-expressing cells, and macrophages. Furthermore, we studied the pharmocokinetics of everolismus. Epithelial damage preceded luminal obliteration, which was eventually total, except when both drugs had been given. In xenografts, an influx of cells with CD8+ cells dominating peaked on day 9, thereafter declining, except in the combination drug group. There, the immunological reaction was delayed and blunted, with CD4+ cells dominating. More macrophages appeared in xenografts than in allografts except with the combination CsA and everolimus. A dose of 1.5 mg/kg everolimus yields adequate blood concentrations for porcine studies. In this xenograft model, chronic rejection appears to be caused by an immune response to the graft, but it is more short-lived than the response in allografts. The combination of CsA and everolimus was able to blunt the response and delay the subsequent obliteration.
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Affiliation(s)
- Paula K Maasilta
- Department of Surgery, Helsinki University Hospital, HUS, Finland.
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Sarbassov DD, Ali SM, Sabatini DM. Growing roles for the mTOR pathway. Curr Opin Cell Biol 2005; 17:596-603. [PMID: 16226444 DOI: 10.1016/j.ceb.2005.09.009] [Citation(s) in RCA: 1196] [Impact Index Per Article: 62.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Accepted: 09/30/2005] [Indexed: 02/08/2023]
Abstract
The mammalian TOR (mTOR) pathway is a key regulator of cell growth and proliferation and increasing evidence suggests that its deregulation is associated with human diseases, including cancer and diabetes. The mTOR pathway integrates signals from nutrients, energy status and growth factors to regulate many processes, including autophagy, ribosome biogenesis and metabolism. Recent work identifying two structurally and functionally distinct mTOR-containing multiprotein complexes and TSC1/2, rheb, and AMPK as upstream regulators of mTOR is beginning to reveal how mTOR can sense diverse signals and produce a myriad of responses.
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Affiliation(s)
- Dos D Sarbassov
- Whitehead Institute, MIT Department of Biology, 9 Cambridge Center, Cambridge, Massachussetts 02142, USA
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