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Ramalingam S, Karuppiah M, Thiruppathi M, Palanivelu S, Panchanatham S. Antioxidant potential of biflavonoid attenuates hyperglycemia by modulating the carbohydrate metabolic enzymes in high fat diet/streptozotocin induced diabetic rats. Redox Rep 2021; 25:1-10. [PMID: 32013797 PMCID: PMC7034448 DOI: 10.1080/13510002.2020.1722914] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Objectives: The present study was to isolate the biflavonoid (a bimolecular kaemferol structured molecule) and test its efficacy on oxidative stress and carbohydrate metabolic key enzymes in control and high fat diet and streptozotocin -induced diabetic rats. Methods: Type 2 diabetes was induced in male albino wistar rats by feeding them with high fat diet comprising of 84.3% standard laboratory chow, 5% lard, 10% yolk powder, cholesterol 0.2%, and 0.5% bile salt for 2 weeks. After 2 weeks, the animals were kept in an overnight fast and injected with low dose of streptozotocin (35 mg/kg, dissolved in 0.1 M sodium citrate buffer, pH 4.5). Results: At the end of the experimental period, diabetic control rats showed significant increase in plasma glucose, homeostatic model assessment of insulin resistance (HOMA-IR), glycosylated hemoglobin (HbA1c) with concomitant decrease in plasma insulin, total hemoglobin and body weight. The activities of key enzymes of carbohydrate metabolism, lipid peroxidation markers, antioxidant enzymes, glycogen content and glycogen synthase and glycogen phosphorylase were also altered in diabetic rats. Discussion: Oral administration of biflavonoid to diabetic rats significantly ameliorated all the biochemical alterations to near normal levels. The effect produced by the biflavonoid on various parameters was comparable to that of metformin.
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Affiliation(s)
- Sundaram Ramalingam
- Department of Medical Biochemistry, University of Madras, Chennai, India.,Department of Biochemistry, Saveetha Dental College & Hospital, Saveetha Institute of Medical &Technical Sciences, Saveetha University, Chennai, India
| | - Muthu Karuppiah
- Department of Chemistry, Manonmaniam Sundaranar University, Tirunelveli, India
| | - Muthusamy Thiruppathi
- Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL, USA
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Ramalingam S, Karuppiah M, Thiruppathi M. Antihyperglycaemic potential of rosmarinic acid attenuates glycoprotein moiety in high-fat diet and streptozotocin-induced diabetic rats. All Life 2020. [DOI: 10.1080/26895293.2020.1733104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- Sundaram Ramalingam
- Department of Biochemistry, Dental College and Hospital, Saveetha University, Chennai, India
- Central Research Laboratory, Meenakshi Academy of Higher Education and Research, Chennai, India
| | - Muthu Karuppiah
- Department of Chemistry, Manomanium Sundaranar University, Tirunelveli, India
| | - Muthusamy Thiruppathi
- Department of Kinesiology and Nutrition, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
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Thiruppathi M, Vahini M, Devendran P, Arunpandian M, Selvakumar K, Ramalingan C, Swaminathan M, Nagarajan ER. CuWO₄ Nanoparticles: Investigation of Dielectric, Electrochemical Behaviour and Photodegradation of Pharmaceutical Waste. J Nanosci Nanotechnol 2019; 19:7026-7034. [PMID: 31039855 DOI: 10.1166/jnn.2019.16601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The hydrothermally synthesized CuWO₄ nanoparticles (NPs) were characterized with different analysis such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Energy Dispersive X-ray Spectroscopy (EDX), Cyclic Voltammetry (CV), UV-Visible and Photoluminescence (PL) analysis. The prepared CuWO₄ NPs were examined with Electrochemical Impedance Spectroscopy (EIS). SEM images show that CuWO₄ NPs are highly spherical shaped morphology and porous in nature. The optical band gap of prepared CuWO₄ NPs is found to be 2.12 eV. Photodegradation of diclofenac sodium (DFS) (medical waste) in the aqueous medium with CuWO₄ NPs under visible light irradiation shows 98% degradation. The CuWO₄ NPs was stable up to 5th cycle it can be used as a reusable photocatalyst for the DFS degradation. The electrical conductivity and dielectric properties of the CuWO₄ NPs at room temperature is analyzed by EIS studies. The bulk conductivity value of the prepared nanoparticles is 1.477×10-5 S/cm at room temperature. The conductivity of CuWO₄ NPs is found to be due to electrons movement. The CuWO₄ NPs shows higher photocatalytic and electrocatalytic activity for decomposition of DFS and methanol electro-oxidation in alkaline medium respectively.
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Affiliation(s)
- M Thiruppathi
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - M Vahini
- Department of Physics, Multifunctional Materials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - P Devendran
- Department of Physics, Multifunctional Materials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - M Arunpandian
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - K Selvakumar
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - C Ramalingan
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - M Swaminathan
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
| | - E R Nagarajan
- Department of Chemistry, Nanomaterials Laboratory, International Research Centre, Kalasalingam Academy of Research and Education, Krishnankoil 626126, Tamil Nadu, India
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Arunpandian M, Selvakumar K, Raja A, Rajasekaran P, Thiruppathi M, Nagarajan E, Arunachalam S. Fabrication of novel Nd2O3/ZnO-GO nanocomposite: An efficient photocatalyst for the degradation of organic pollutants. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.01.058] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Fang MM, Barman PK, Thiruppathi M, Mirza RE, McKinney RD, Deng J, Christman JW, Du X, Fukai T, Ennis WJ, Koh TJ, Ushio-Fukai M, Urao N. Oxidant Signaling Mediated by Nox2 in Neutrophils Promotes Regenerative Myelopoiesis and Tissue Recovery following Ischemic Damage. J Immunol 2018; 201:2414-2426. [PMID: 30201810 DOI: 10.4049/jimmunol.1800252] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 08/06/2018] [Indexed: 01/09/2023]
Abstract
Ischemic tissue damage activates hematopoietic stem and progenitor cells (HSPCs) in the bone marrow (BM)-generating myeloid cells, and persistent HSPC activity may drive chronic inflammation and impair tissue recovery. Although increased reactive oxygen species in the BM regulate HSPC functions, their roles in myelopoiesis of activated HSPCs and subsequent tissue recovery during ischemic damage are not well understood. In this paper, we report that deletion of Nox2 NADPH oxidase in mice results in persistent elevations in BM HSPC activity and levels of inflammatory monocytes/macrophages in BM and ischemic tissue in a model of hindlimb ischemia. Ischemic tissue damage induces oxidants in BM such as elevations of hydrogen peroxide and oxidized phospholipids, which activate redox-sensitive Lyn kinase in a Nox2-dependent manner. Moreover, during tissue recovery after ischemic injury, this Nox2-ROS-Lyn kinase axis is induced by Nox2 in neutrophils that home to the BM, which inhibits HSPC activity and inflammatory monocyte generation and promotes tissue regeneration after ischemic damage. Thus, oxidant signaling in the BM mediated by Nox2 in neutrophils regulates myelopoiesis of HSPCs to promote regeneration of damaged tissue.
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Affiliation(s)
- Milie M Fang
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612
| | - Pijus K Barman
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612
| | - Muthusamy Thiruppathi
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612
| | - Rita E Mirza
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612
| | - Ronald D McKinney
- Department of Pharmacology, Center for Cardiovascular Research, University of Illinois at Chicago College of Medicine, Chicago, IL 60612
| | - Jing Deng
- Department of Medicine, Ohio State University School of Medicine, Columbus, OH 43210.,Department of Medicine, University of Illinois at Chicago College of Medicine, Chicago, IL 60612
| | - John W Christman
- Department of Medicine, Ohio State University School of Medicine, Columbus, OH 43210.,Department of Medicine, University of Illinois at Chicago College of Medicine, Chicago, IL 60612
| | - Xiaoping Du
- Department of Pharmacology, Center for Cardiovascular Research, University of Illinois at Chicago College of Medicine, Chicago, IL 60612
| | - Tohru Fukai
- Vascular Biology Center, Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912.,Charlie Norwood Veterans Affairs Medical Center, Augusta, GA 30904
| | - William J Ennis
- Department of Surgery, University of Illinois at Chicago College of Medicine, Chicago, IL 60612; and
| | - Timothy J Koh
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612
| | - Masuko Ushio-Fukai
- Vascular Biology Center, Department of Medicine (Cardiology), Medical College of Georgia at Augusta University, Augusta, GA 30912
| | - Norifumi Urao
- Center for Wound Healing and Tissue Regeneration, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL 60612; .,Department of Pharmacology, Center for Cardiovascular Research, University of Illinois at Chicago College of Medicine, Chicago, IL 60612
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Jagadeeswaran R, Vazquez BA, Thiruppathi M, Ganesh BB, Ibanez V, Cui S, Engel JD, Diamond AM, Molokie RE, DeSimone J, Lavelle D, Rivers A. Pharmacological inhibition of LSD1 and mTOR reduces mitochondrial retention and associated ROS levels in the red blood cells of sickle cell disease. Exp Hematol 2017; 50:46-52. [PMID: 28238805 DOI: 10.1016/j.exphem.2017.02.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 02/06/2017] [Accepted: 02/08/2017] [Indexed: 12/21/2022]
Abstract
Sickle cell disease (SCD), an inherited blood disorder caused by a point mutation that renders hemoglobin susceptible to polymerization when deoxygenated, affects millions of people worldwide. Manifestations of SCD include chronic hemolytic anemia, inflammation, painful vaso-occlusive crises, multisystem organ damage, and reduced life expectancy. Part of SCD pathophysiology is the excessive formation of intracellular reactive oxygen species (ROS) in SCD red blood cells (RBCs), which accelerates their hemolysis. Normal RBC precursors eliminate their mitochondria during the terminal differentiation process. Strikingly, we observed an increased percentage of RBCs retaining mitochondria in SCD patient blood samples compared with healthy individuals. In addition, using an experimental SCD mouse model, we demonstrate that excessive levels of ROS in SCD are associated with this abnormal mitochondrial retention. Interestingly, the LSD1 inhibitor, RN-1, and the mitophagy-inducing agent mammalian target of rapamycin (mTOR) inhibitor, sirolimus, increased RBC lifespan and reduced ROS accumulation in parallel with reducing mitochondria-retaining RBCs in the SCD mouse model. Furthermore, gene expression analysis of SCD mice treated with RN-1 showed increased expression of mitophagy genes. Our findings suggest that reduction of mitochondria-retaining RBCs may provide a new therapeutic approach to preventing excessive ROS in SCD.
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Affiliation(s)
- Ramasamy Jagadeeswaran
- Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA
| | - Benjamin A Vazquez
- Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA
| | - Muthusamy Thiruppathi
- Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL, USA
| | - Balaji B Ganesh
- Research Resources Center, University of Illinois at Chicago, Chicago, IL, USA
| | - Vinzon Ibanez
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA; Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Shuaiying Cui
- Department of Medicine, Boston University School of Medicine, Boston, MA, USA
| | - James D Engel
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Alan M Diamond
- Department of Pathology, University of Illinois at Chicago, Chicago, IL, USA
| | - Robert E Molokie
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA; Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Joseph DeSimone
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA; Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Donald Lavelle
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA; Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Angela Rivers
- Department of Pediatrics, University of Illinois at Chicago, Chicago, IL, USA; Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA.
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Kong S, Dong H, Song J, Thiruppathi M, Prabhakar BS, Qiu Q, Lin Z, Chini E, Zhang B, Fang D. Deleted in Breast Cancer 1 Suppresses B Cell Activation through RelB and Is Regulated by IKKα Phosphorylation. J Immunol 2015; 195:3685-93. [PMID: 26378077 DOI: 10.4049/jimmunol.1500713] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/13/2015] [Indexed: 01/08/2023]
Abstract
Alternative NF-κB signaling is crucial for B cell activation and Ig production, and it is mainly regulated by the inhibitor of κ B kinase (IKK) regulatory complex. Dysregulation of alternative NF-κB signaling in B cells could therefore lead to hyperactive B cells and Ig overproduction. In our previous, study we found that deleted in breast cancer 1 (DBC1) is a suppressor of the alternative NF-κB pathway to attenuate B cell activation. In this study, we report that loss of DBC1 results in spontaneous overproduction of Ig in mice after 10 mo of age. Using a double mutant genetic model, we confirm that DBC1 suppresses B cell activation through RelB inhibition. At the molecular level, we show that DBC1 interacts with alternative NF-κB members RelB and p52 through its leucine zipper domain. In addition, phosphorylation of DBC1 at its C terminus by IKKα facilitates its interaction with RelB and IKKα, indicating that DBC1-mediated suppression of alternative NF-κB is regulated by IKKα. Our results define the molecular mechanism of DBC1 inhibition of alternative NF-κB activation in suppressing B cell activation.
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Affiliation(s)
- Sinyi Kong
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago IL 60611
| | - Hongxin Dong
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago IL 60611
| | - Jianxun Song
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA 17033
| | - Muthusamy Thiruppathi
- Department of Microbiology and Immunology, University of Illinois College of Medicine Chicago, Chicago, IL 60612
| | - Bellur S Prabhakar
- Department of Microbiology and Immunology, University of Illinois College of Medicine Chicago, Chicago, IL 60612
| | - Quan Qiu
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago IL 60611
| | - Zhenghong Lin
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago IL 60611
| | - Eduardo Chini
- Laboratory of Signal Transduction, Department of Anesthesiology, Mayo Clinic College of Medicine, Rochester, MN 55905; Robert and Arlene Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Bin Zhang
- Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL 60611; and Division of Hematology/Oncology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Deyu Fang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago IL 60611;
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Bhattacharya P, Thiruppathi M, Elshabrawy HA, Alharshawi K, Kumar P, Prabhakar BS. GM-CSF: An immune modulatory cytokine that can suppress autoimmunity. Cytokine 2015; 75:261-71. [PMID: 26113402 DOI: 10.1016/j.cyto.2015.05.030] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 05/22/2015] [Accepted: 05/25/2015] [Indexed: 12/12/2022]
Abstract
GM-CSF was originally identified as a colony stimulating factor (CSF) because of its ability to induce granulocyte and macrophage populations from precursor cells. Multiple studies have demonstrated that GM-CSF is also an immune-modulatory cytokine, capable of affecting not only the phenotype of myeloid lineage cells, but also T-cell activation through various myeloid intermediaries. This property has been implicated in the sustenance of several autoimmune diseases like arthritis and multiple sclerosis. In contrast, several studies using animal models have shown that GM-CSF is also capable of suppressing many autoimmune diseases such as Crohn's disease, Type-1 diabetes, Myasthenia gravis and experimental autoimmune thyroiditis. Knockout mouse studies have suggested that the role of GM-CSF in maintaining granulocyte and macrophage populations in the physiological steady state is largely redundant. Instead, its immune-modulatory role plays a significant role in the development or resolution of autoimmune diseases. This is mediated either through the differentiation of precursor cells into specialized non-steady state granulocytes, macrophages and dendritic cells, or through the modulation of the phenotype of mature myeloid cells. Thus, outside of myelopoiesis, GM-CSF has a profound role in regulating the immune response and maintaining immunological tolerance.
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Affiliation(s)
- Palash Bhattacharya
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Muthusamy Thiruppathi
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Hatem A Elshabrawy
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Khaled Alharshawi
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Prabhakaran Kumar
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA
| | - Bellur S Prabhakar
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, IL 60612, USA.
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Bhattacharya P, Budnick I, Singh M, Thiruppathi M, Alharshawi K, Elshabrawy H, Holterman MJ, Prabhakar BS. Dual Role of GM-CSF as a Pro-Inflammatory and a Regulatory Cytokine: Implications for Immune Therapy. J Interferon Cytokine Res 2015; 35:585-99. [PMID: 25803788 DOI: 10.1089/jir.2014.0149] [Citation(s) in RCA: 166] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Granulocyte macrophage colony stimulating factor (GM-CSF) is generally recognized as an inflammatory cytokine. Its inflammatory activity is primarily due its role as a growth and differentiation factor for granulocyte and macrophage populations. In this capacity, among other clinical applications, it has been used to bolster anti-tumor immune responses. GM-CSF-mediated inflammation has also been implicated in certain types of autoimmune diseases, including rheumatoid arthritis and multiple sclerosis. Thus, agents that can block GM-CSF or its receptor have been used as anti-inflammatory therapies. However, a review of literature reveals that in many situations GM-CSF can act as an anti-inflammatory/regulatory cytokine. We and others have shown that GM-CSF can modulate dendritic cell differentiation to render them "tolerogenic," which, in turn, can increase regulatory T-cell numbers and function. Therefore, the pro-inflammatory and regulatory effects of GM-CSF appear to depend on the dose and the presence of other relevant cytokines in the context of an immune response. A thorough understanding of the various immunomodulatory effects of GM-CSF will facilitate more appropriate use and thus further enhance its clinical utility.
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Affiliation(s)
- Palash Bhattacharya
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Isadore Budnick
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Medha Singh
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Muthusamy Thiruppathi
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Khaled Alharshawi
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Hatem Elshabrawy
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
| | - Mark J Holterman
- 2 Department of Surgery, College of Medicine, University of Illinois , Chicago, Illinois
| | - Bellur S Prabhakar
- 1 Department of Microbiology and Immunology, College of Medicine, University of Illinois , Chicago, Illinois
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Kong S, Thiruppathi M, Qiu Q, Lin Z, Dong H, Chini EN, Prabhakar BS, Fang D. DBC1 is a suppressor of B cell activation by negatively regulating alternative NF-κB transcriptional activity. J Immunol 2014; 193:5515-24. [PMID: 25362179 DOI: 10.4049/jimmunol.1401798] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
CD40 and BAFFR signaling play important roles in B cell proliferation and Ig production. In this study, we found that B cells from mice with deletion of Dbc1 gene (Dbc1(-/-)) show elevated proliferation, and IgG1 and IgA production upon in vitro CD40 and BAFF, but not BCR and LPS stimulation, indicating that DBC1 inhibits CD40/BAFF-mediated B cell activation in a cell-intrinsic manner. Microarray analysis and chromatin immunoprecipitation experiments reveal that DBC1 inhibits B cell function by selectively suppressing the transcriptional activity of alternative NF-κB members RelB and p52 upon CD40 stimulation. As a result, when immunized with nitrophenylated-keyhole limpet hemocyanin, Dbc1(-/-) mice produce significantly increased levels of germinal center B cells, plasma cells, and Ag-specific Ig. Finally, loss of DBC1 in mice leads to higher susceptibility to experimental autoimmune myasthenia gravis. Our study identifies DBC1 as a novel regulator of B cell activation by suppressing the alternative NF-κB pathway.
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Affiliation(s)
- Sinyi Kong
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Muthusamy Thiruppathi
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Chicago, IL 60612
| | - Quan Qiu
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Zhenghong Lin
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Hongxin Dong
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611; Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL 60611; and
| | - Eduardo N Chini
- Laboratory of Signal Transduction, Department of Anesthesiology and Robert and Arlene Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Bellur S Prabhakar
- Department of Microbiology and Immunology, University of Illinois College of Medicine, Chicago, Chicago, IL 60612
| | - Deyu Fang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611;
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Abstract
Forkhead box P3 (FOXP3) is a transcription factor necessary for the function of regulatory T cells (T(reg) cells). T(reg) cells maintain immune homeostasis and self-tolerance and play an important role in the prevention of autoimmune disease. Here, we discuss the role of T(reg) cells in the pathogenesis of myasthenia gravis (MG) and review evidence indicating that a significant defect in T(reg) cell in vitro suppressive function exists in MG patients, without an alteration in circulating frequency. This functional defect is associated with a reduced expression of key functional molecules, such as FOXP3 on isolated T(reg) cells, and appears to be more pronounced in immunosuppression-naive MG patients. In vitro administration of granulocyte macrophage-colony-stimulating factor (GM-CSF) enhanced the suppressive function of T(reg) cells and upregulated FOXP3 expression. These findings indicate a clinically relevant T(reg) cell-intrinsic defect in immune regulation in MG that may reveal a novel therapeutic target.
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Affiliation(s)
- Muthusamy Thiruppathi
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois Hospital and Health Sciences System, Chicago, USA
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Rowin J, Thiruppathi M, Arhebamen E, Sheng J, Prabhakar BS, Meriggioli MN. Granulocyte macrophage colony-stimulating factor treatment of a patient in myasthenic crisis: effects on regulatory T cells. Muscle Nerve 2012; 46:449-53. [PMID: 22907239 DOI: 10.1002/mus.23488] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
INTRODUCTION In this study we describe a patient with a prolonged myasthenic crisis refractory to conventional immunomodulatory therapy who was treated with GM-CSF (granulocyte macrophage colony-stimulating factor, sargramostim). METHODS T-regulatory cell (Treg) suppressive function and Foxp3 expression were evaluated before and after treatment with GM-CSF. RESULTS Treatment with GM-CSF was associated with clinical improvement, expansion in the circulating numbers of Foxp3(+) cells, increase in Foxp3 expression levels in Tregs, early improvement in Treg suppressive capacity for AChR-α-induced T-cell proliferation, and subsequent enhancement in Treg suppression of polyclonal T-cell proliferation. CONCLUSION Although definitive conclusions cannot be drawn from a single case, the correlation with similar findings in GM-CSF-treated animals with experimental autoimmune myasthenia gravis suggests further exploration of the effects of GM-CSF in myasthenia gravis should be studied in a clinical trial setting.
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Affiliation(s)
- Julie Rowin
- Department of Neurology and Rehabilitation, University of Illinois Medical Center, 912 South Wood Street, 855N, M/C 796, Chicago, Illinois 60612, USA.
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Rowin J, Thiruppathi M, Arhebamen E, Sheng JR, Prabhakar B, Meriggioli M. GM-CSF Treatment of a Patient in Myasthenic Crisis: Clinical Outcome and Effects on Regulatory T Cells (Tregs) (S35.005). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.s35.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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