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Kowluru A. Roles of GTP and Rho GTPases in pancreatic islet beta cell function and dysfunction. Small GTPases 2020; 12:323-335. [PMID: 32867592 DOI: 10.1080/21541248.2020.1815508] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
A growing body of evidence implicates requisite roles for GTP and its binding proteins (Rho GTPases) in the cascade of events leading to physiological insulin secretion from the islet beta cell. Interestingly, chronic exposure of these cells to hyperglycaemic conditions appears to result in sustained activation of specific Rho GTPases (e.g. Rac1) leading to significant alterations in cellular functions including defects in mitochondrial function and nuclear collapse culminating in beta cell demise. One of the objectives of this review is to highlight our current understanding of the regulatory roles of GTP and Rho GTPases in normal islet function (e.g. proliferation and insulin secretion) as well potential defects in these signalling molecules and metabolic pathways that could contribute islet beta cell dysfunction and loss of functional beta cell mass leading to the onset of diabetes. Potential knowledge gaps in this field and possible avenues for future research are also highlighted. ABBREVIATIONS ARNO: ADP-ribosylation factor nucleotide binding site opener; CML: carboxyl methylation; Epac: exchange protein directly activated by cAMP; ER stress: endoplasmic reticulum stress; FTase: farnesyltransferase; GAP: GTPase activating protein; GDI: GDP dissociation inhibitor; GEF: guanine nucleotide exchange factor; GGTase: geranylgeranyltransferase; GGpp: geranylgeranylpyrophosphate; GGPPS: geranylgeranyl pyrophosphate synthase; GSIS: glucose-stimulated insulin secretion; HGPRTase: hypoxanthine-guanine phosphoribosyltransferase; IMPDH: inosine monophosphate dehydrogenase; α-KIC: α-ketoisocaproic acid; MPA: mycophenolic acid; MVA: mevalonic acid; NDPK: nucleoside diphosphate kinase; NMPK: nucleoside monophosphate kinase; Nox2: phagocyte-like NADPH oxidase; PAK-I: p21-activated kinase-I; β-PIX: β-Pak-interacting exchange factor; PRMT: protein arginine methyltransferase; Rac1: ras-related C3 botulinum toxin substrate 1; Tiam1: T-cell lymphoma invasion and metastasis-inducing protein 1; Trx-1: thioredoxin-1; Vav2: vav guanine nucleotide exchange factor 2.
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Affiliation(s)
- Anjaneyulu Kowluru
- Biomedical Research Service, John D. Dingell VA Medical Center and Department of Pharmaceutical Sciences and Medicine, Wayne State University, Detroit, MI, USA
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2
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Huang X, Huang Q, He Y, Chen S, Li T. Mycophenolic acid enhanced lipopolysaccharide-induced interleukin-18 release in THP-1 cells via activation of the NLRP3 inflammasome. Immunopharmacol Immunotoxicol 2019; 41:521-526. [PMID: 31429348 DOI: 10.1080/08923973.2019.1652913] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Background: Interleukin (IL)-18 is a pro-inflammatory cytokine that has important functions in host defense. The maturation and secretion of IL-18 has been shown to be regulated by the NOD-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome. Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), in association with lipopolysaccharide (LPS), is able to promote the secretion of IL-18, but the mechanism remains unknown. This study aims to explore the mechanism by which MPA synergizes with LPS to induced IL-18 release. Methods: THP-1 cells were stimulated with LPS and MPA and treated with or without the inhibitors of caspase-1, Ac-YVAD-cmk or KCl; IL-18 in the supernatants was measured by ELISA. The intracellular protein levels of NF-κB p-p65, pro-IL-18, NLRP3, and cleaved caspase-1(p20) were measured by Western blot. Results: We found that MPA alone failed to induce IL-18, whereas MPA enhanced LPS-mediated IL-18 release. MPA did not affect the intracellular protein levels of NF-κB p-p65 or pro-IL-18 but activated the NLRP3 inflammasome. Ac-YVAD-cmk or increasing extracellular K+ blocked the activation of caspase-1 and attenuated the release of IL-18. Conclusions: Taken together, MPA synergized with LPS to induce the release of IL-18 via activating the NLRP3 inflammasome and increasing the degradation of pro-IL-18, rather than by enhancing the production of pro-IL-18.
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Affiliation(s)
- Xuechan Huang
- Department of Rheumatology and Immunology, Guangdong Second Provincial General Hospital , Guangzhou , PR China.,The Second School of Clinical Medicine, Southern Medical University , Guangzhou , PR China
| | - Qidang Huang
- Department of Rheumatology and Immunology, Guangdong Second Provincial General Hospital , Guangzhou , PR China.,The Second School of Clinical Medicine, Southern Medical University , Guangzhou , PR China
| | - Yi He
- Department of Rheumatology and Immunology, The Third Affiliated Hospital, Southern Medical University , Guangzhou , PR China.,Institute of Clinical Immunology, Academy of Orthopedics , Guangzhou , PR China
| | - Shuyang Chen
- Department of Rheumatology and Immunology, Guangdong Second Provincial General Hospital , Guangzhou , PR China.,The Second School of Clinical Medicine, Southern Medical University , Guangzhou , PR China
| | - Tianwang Li
- Department of Rheumatology and Immunology, Guangdong Second Provincial General Hospital , Guangzhou , PR China.,The Second School of Clinical Medicine, Southern Medical University , Guangzhou , PR China
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Fernández-Ramos AA, Marchetti-Laurent C, Poindessous V, Antonio S, Petitgas C, Ceballos-Picot I, Laurent-Puig P, Bortoli S, Loriot MA, Pallet N. A comprehensive characterization of the impact of mycophenolic acid on the metabolism of Jurkat T cells. Sci Rep 2017; 7:10550. [PMID: 28874730 PMCID: PMC5585210 DOI: 10.1038/s41598-017-10338-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/02/2017] [Indexed: 12/23/2022] Open
Abstract
Metabolic reprogramming is critical for T cell fate and polarization and is regulated by metabolic checkpoints, including Myc, HIF-1α, AMPK and mTORC1. Our objective was to determine the impact of mycophenolic acid (MPA) in comparison with rapamycin (Rapa), an inhibitor of mTORC1, on the metabolism of Jurkat T cells. We identified a drug-specific transcriptome signature consisting of the key enzymes and transporters involved in glycolysis, glutaminolysis or nucleotide synthesis. MPA produced an early and transient drop in the intracellular ATP content related to the inhibition of de novo synthesis of purines, leading to the activation of the energy sensor AMPK. MPA decreases glycolytic flux, consistent with a reduction in glucose uptake, but also in the oxidation of glutamine. Additionally, both drugs reduce aerobic glycolysis. The expression of HIF-1α and Myc, promoting the activation of glycolysis and glutaminolysis, was inhibited by MPA and Rapa. In conclusion, we report that MPA profoundly impacts the cellular metabolism of Jurkat T cells by generating an energetic distress, decreasing the glycolytic and glutaminolytic fluxes and by targeting HIF-1α and Myc. These findings open interesting perspectives for novel combinatorial therapeutic strategies targeting metabolic checkpoints to block the proliferation of T cells.
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Affiliation(s)
- Ana A Fernández-Ramos
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France
| | - Catherine Marchetti-Laurent
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France
| | - Virginie Poindessous
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France
| | - Samantha Antonio
- Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,INSERM UMR-S 1124, 45 rue des Saints-Pères, 75006, Paris, France
| | - Céline Petitgas
- Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,Assistance Publique-Hôpitaux de Paris, Hôpital Necker-Enfants Malades, Laboratoire de Biochimie métabolomique et protéomique, 149 rue de Sèvres, 75015, Paris, France
| | - Irène Ceballos-Picot
- Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,Assistance Publique-Hôpitaux de Paris, Hôpital Necker-Enfants Malades, Laboratoire de Biochimie métabolomique et protéomique, 149 rue de Sèvres, 75015, Paris, France
| | - Pierre Laurent-Puig
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, 75015, Paris, France
| | - Sylvie Bortoli
- Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,INSERM UMR-S 1124, 45 rue des Saints-Pères, 75006, Paris, France
| | - Marie-Anne Loriot
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France.,Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, 75015, Paris, France
| | - Nicolas Pallet
- INSERM UMR-S 1147, Centre Universitaire des Saints-Pères, 45 rue des Saints-Pères, 75006, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité. 45, rue des Saints-Pères, 75006, Paris, France. .,Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, 75015, Paris, France.
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Jeong KH, Joo HJ, Kim JE, Park YM, Kang H. Effect of mycophenolic acid on proliferation of dermal papilla cells and induction of anagen hair follicles. Clin Exp Dermatol 2015; 40:894-902. [DOI: 10.1111/ced.12650] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2014] [Indexed: 12/19/2022]
Affiliation(s)
- K. H. Jeong
- Department of Dermatology; St. Paul's Hospital; College of Medicine; Catholic University of Korea; Seoul Korea
| | - H. J. Joo
- Department of Dermatology; St. Paul's Hospital; College of Medicine; Catholic University of Korea; Seoul Korea
| | - J. E. Kim
- Department of Dermatology; St. Paul's Hospital; College of Medicine; Catholic University of Korea; Seoul Korea
| | - Y. M. Park
- Department of Dermatology; Seoul St. Mary's Hospital; College of Medicine; Catholic University of Korea; Seoul Korea
| | - H. Kang
- Department of Dermatology; St. Paul's Hospital; College of Medicine; Catholic University of Korea; Seoul Korea
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Lee JI, Kim JY, Lee JG, Kim YS. Islet Encapsulation Using Chondrocyte. KOREAN JOURNAL OF TRANSPLANTATION 2014. [DOI: 10.4285/jkstn.2014.28.4.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Jeong Ik Lee
- Department of Veterinary Medicine, College of Veterinary Medicine, Konkuk University, Seoul, Korea
- Department of Biomedical Science and Technology, Konkuk University, Seoul, Korea
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Ye Kim
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea
| | - Jae Geun Lee
- Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea
| | - Yu Seun Kim
- The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea
- Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea
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Huh K, Cho Y, Kim B, Joo D, Kim M, Kim Y. PRMT3: New Binding Molecule to RhoGDI-α During Mycophenolic Acid–induced β-cell Death. Transplant Proc 2014; 46:1229-32. [DOI: 10.1016/j.transproceed.2013.12.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 11/26/2013] [Accepted: 12/10/2013] [Indexed: 11/25/2022]
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Huh KH, Cho Y, Kim BS, Do JH, Park YJ, Joo DJ, Kim MS, Kim YS. The role of thioredoxin 1 in the mycophenolic acid-induced apoptosis of insulin-producing cells. Cell Death Dis 2013; 4:e721. [PMID: 23846223 PMCID: PMC3730420 DOI: 10.1038/cddis.2013.247] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 06/07/2013] [Accepted: 06/07/2013] [Indexed: 01/12/2023]
Abstract
Mycophenolic acid (MPA) is one of many effective immunosuppressive drugs. However, MPA can induce cellular toxicity and impair cellular function in β-cells. To explore the effects of MPA and the relation between MPA and Trx-1, we used various methods, including an Illumina microarray, to identify the genes regulated during pancreatic β-cell death following MPA treatment. INS-1E cells (a pancreatic β-cell line) and isolated rat islets were treated with MPA for 12, 24, or 36 h, and subsequent microarray analysis showed that (Trx1) gene expression was significantly reduced by MPA. Further, Trx1 overexpression increased the cell viability, decreased the activations of c-jun N-terminal kinase (JNK) and caspase-3 by MPA, and attenuated ROS upregulation by MPA. Furthermore, siRNA knockdown of Trx1 increased MPA-induced cell death and the activations of p-JNK and caspase-3, and MPA significantly provoked the apoptosis of insulin-secreting cells via Trx1 downregulation. Our findings suggest that the prevention of Trx1 downregulation in response to MPA is critical for successful islet transplantation.
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Affiliation(s)
- K H Huh
- Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Republic of Korea
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Gallo R, Natale M, Vendrame F, Boggi U, Filipponi F, Marchetti P, Laghi Pasini F, Dotta F. In vitro effects of mycophenolic acid on survival, function, and gene expression of pancreatic beta-cells. Acta Diabetol 2012; 49 Suppl 1:S123-31. [PMID: 22249339 DOI: 10.1007/s00592-011-0368-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 12/23/2011] [Indexed: 12/24/2022]
Abstract
Post-transplant diabetes mellitus represents an important complication of prolonged immunosuppressive treatment after solid organ transplantation. The immunosuppressive toxicity, responsible for a persistent impairment of glucose metabolism in pancreatic islet-transplanted patients, is mainly attributed to calcineurin inhibitors and steroids, while other immunosuppressive molecules (azathioprine and mycophenolic acid, MPA) are considered not to have a toxic effect. In the present study, in vitro effects of MPA have been investigated in mouse beta-cell lines (βTC-1 and βTC-6) and in purified human pancreatic islets. βTC-1, βTC-6, and human pancreatic islets were exposed to various concentrations of MPA for different times. Consequently, we evaluated the viability, the induction of apoptosis, the glucose-stimulated insulin secretion, and the expression of β-cell function genes (Isl1, Pax6, Glut-2, glucokinase) and apoptosis-related genes (Bax and Bcl2). βTC-1, βTC-6, and human islets treated, respectively, for 48 and 72 h with 15-30 nM MPA showed altered islet architecture, as compared with control cells. We observed for βTC-1 and βTC-6 almost 70% reduction in cell viability; three to sixfold induction of TUNEL/apoptotic-positive cells quantified by FACS analysis. A twofold increase in apoptotic cells was observed in human islets after MPA exposure associated with strong inhibition of glucose-stimulated insulin secretion. Furthermore, we showed significant down-regulation of gene expression of molecules involved in β-cell function and increase rate between Bax/Bcl2. Our data demonstrate that MPA has an in vitro diabetogenic effect interfering at multiple levels with survival and function of murine and human pancreatic β-cells.
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Affiliation(s)
- R Gallo
- Department of Internal Medicine, Diabetes Unit, Endocrine and Metabolic Sciences and Biochemistry, University of Siena, Viale Bracci 18, 53100 Siena, Italy
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Park YJ, Ahn HJ, Kim YS, Cho Y, Joo DJ, Ju MK. Illumina-microarray analysis of mycophenolic acid-induced cell death in an insulin-producing cell line and primary rat islet cells: New insights into apoptotic pathways involved. Cell Signal 2010; 22:1773-82. [DOI: 10.1016/j.cellsig.2010.07.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Accepted: 07/07/2010] [Indexed: 11/25/2022]
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Mycophenolic acid inhibits the phosphorylation of NF-kappaB and JNKs and causes a decrease in IL-8 release in H2O2-treated human renal proximal tubular cells. Chem Biol Interact 2010; 185:253-62. [PMID: 20302854 DOI: 10.1016/j.cbi.2010.03.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 03/08/2010] [Accepted: 03/09/2010] [Indexed: 11/21/2022]
Abstract
Ischaemia-reperfusion injury is a common occurrence in renal transplantation and may affect the long-term survival of the allograft. Oxidative stress may play a crucial role in this, with reactive oxygen species formed during reperfusion causing direct cellular damage as well as activating pro-inflammatory pathways. A human proximal tubule cell line (HK-2) was subjected to hydrogen peroxide (H(2)O(2)) stress that resulted in phosphorylation of c-jun N-terminal kinases (JNKs) and the transcription factor NF-kappaB at Ser276, both of which have been associated with inflammation. Interleukin (IL)-8 production also increased upon H(2)O(2) stimulation. Pre-incubation of the cells with mycophenolic acid (MPA) resulted in reduced phosphorylation of both JNKs and NF-kappaB, and reduced IL-8 release in H(2)O(2)-stimulated HK-2 cells. MPA also reduced the H(2)O(2)-induced phosphorylation of p38 MAP (mitogen-activated protein) kinase, the extracellular-signal regulated kinase 1/2 (ERK1/2), Akt kinase and the transcription factor CREB (cyclic AMP response element binding protein). In rat kidneys subjected to ischaemia-reperfusion, an increase in both pJNK1/2 and pNF-kappaB was observed, which was reduced in kidneys obtained from mycophenolate mofetil (MMF)-treated rats. These results suggest that MPA may inhibit pro-inflammatory responses in the kidney by inhibiting activation of pro-inflammatory molecules in both the kidney and human renal proximal tubular cells subjected to oxidative stress.
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Abstract
Glucose-stimulated insulin secretion from the islet beta-cell involves a sequence of metabolic events and an interplay between a wide range of signaling pathways leading to the generation of second messengers (e.g., cyclic nucleotides, adenine and guanine nucleotides, soluble lipid messengers) and mobilization of calcium ions. Consequent to the generation of necessary signals, the insulin-laden secretory granules are transported from distal sites to the plasma membrane for fusion and release of their cargo into the circulation. The secretory granule transport underlies precise changes in cytoskeletal architecture involving a well-coordinated cross-talk between various signaling proteins, including small molecular mass GTP-binding proteins (G proteins) and their respective effector proteins. The purpose of this article is to provide an overview of current understanding of the identity of small G proteins (e.g., Cdc42, Rac1, and ARF-6) and their corresponding regulatory factors (e.g., GDP/GTP-exchange factors, GDP-dissociation inhibitors) in the pancreatic beta-cell. Plausible mechanisms underlying regulation of these signaling proteins by insulin secretagogues are also discussed. In addition to their positive modulatory roles, certain small G proteins also contribute to the metabolic dysfunction and demise of the islet beta-cell seen in in vitro and in vivo models of impaired insulin secretion and diabetes. Emerging evidence also suggests significant insulin secretory abnormalities in small G protein knockout animals, further emphasizing vital roles for these proteins in normal health and function of the islet beta-cell. Potential significance of these experimental observations from multiple laboratories and possible avenues for future research in this area of islet research are highlighted.
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Affiliation(s)
- Anjaneyulu Kowluru
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, 259 Mack Avenue, Detroit, MI 48202-3489, USA.
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The RhoGDI-α/JNK signaling pathway plays a significant role in mycophenolic acid-induced apoptosis in an insulin-secreting cell line. Cell Signal 2009; 21:356-64. [DOI: 10.1016/j.cellsig.2008.11.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2008] [Revised: 11/12/2008] [Accepted: 11/12/2008] [Indexed: 11/23/2022]
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Chaigne-Delalande B, Guidicelli G, Couzi L, Merville P, Mahfouf W, Bouchet S, Molimard M, Pinson B, Moreau JF, Legembre P. The immunosuppressor mycophenolic acid kills activated lymphocytes by inducing a nonclassical actin-dependent necrotic signal. THE JOURNAL OF IMMUNOLOGY 2008; 181:7630-8. [PMID: 19017951 DOI: 10.4049/jimmunol.181.11.7630] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mycophenolate mofetil (MMF) is an immunosuppressive agent used in transplantation. Over the last decade, MMF has also emerged as an alternative therapeutic regimen for autoimmune diseases, mainly for patients refractory to other therapies. The active compound of MMF, mycophenolic acid (MPA), depletes the intracellular pool of guanosine tri-phosphate through inosine monophosphate dehydrogenase blockade. The molecular mechanism involved in the elimination of T and B lymphocytes upon inhibition of inosine monophosphate dehydrogenase remains elusive. In this study, we showed that in contrast to the immunosuppressors azathioprine, cyclosporin A, and tacrolimus, MPA killed lymphocytes through the activation of a caspase-independent necrotic signal. Furthermore, the MPA-mediated necrotic signal relied on the transmission of a novel intracellular signal involving Rho-GTPase Cdc42 activity and actin polymerization. In addition to its medical interest, this study sheds light on a novel and atypical molecular mechanism leading to necrotic cell death.
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Molecular Mechanisms of Cell Death of Mycophenolic Acid-Treated Primary Isolated Rat Islets: Implication of Mitogen-Activated Protein Kinase Activation. Transplant Proc 2008; 40:2575-7. [DOI: 10.1016/j.transproceed.2008.07.123] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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