1
|
Vilas-Boas EA, Almeida DC, Roma LP, Ortis F, Carpinelli AR. Lipotoxicity and β-Cell Failure in Type 2 Diabetes: Oxidative Stress Linked to NADPH Oxidase and ER Stress. Cells 2021; 10:cells10123328. [PMID: 34943836 PMCID: PMC8699655 DOI: 10.3390/cells10123328] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/18/2021] [Accepted: 11/22/2021] [Indexed: 12/17/2022] Open
Abstract
A high caloric intake, rich in saturated fats, greatly contributes to the development of obesity, which is the leading risk factor for type 2 diabetes (T2D). A persistent caloric surplus increases plasma levels of fatty acids (FAs), especially saturated ones, which were shown to negatively impact pancreatic β-cell function and survival in a process called lipotoxicity. Lipotoxicity in β-cells activates different stress pathways, culminating in β-cells dysfunction and death. Among all stresses, endoplasmic reticulum (ER) stress and oxidative stress have been shown to be strongly correlated. One main source of oxidative stress in pancreatic β-cells appears to be the reactive oxygen species producer NADPH oxidase (NOX) enzyme, which has a role in the glucose-stimulated insulin secretion and in the β-cell demise during both T1 and T2D. In this review, we focus on the acute and chronic effects of FAs and the lipotoxicity-induced β-cell failure during T2D development, with special emphasis on the oxidative stress induced by NOX, the ER stress, and the crosstalk between NOX and ER stress.
Collapse
Affiliation(s)
- Eloisa Aparecida Vilas-Boas
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, Brazil
- Department of Biochemistry, Institute of Chemistry, University of São Paulo (USP), São Paulo 05508-900, Brazil
- Correspondence: (E.A.V.-B.); (A.R.C.); Tel.: +55-(11)-3091-7246 (A.R.C.)
| | - Davidson Correa Almeida
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, Brazil; (D.C.A.); (F.O.)
| | - Leticia Prates Roma
- Center for Human and Molecular Biology (ZHMB), Department of Biophysics, Saarland University, 66424 Homburg, Germany;
| | - Fernanda Ortis
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, Brazil; (D.C.A.); (F.O.)
| | - Angelo Rafael Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, Brazil
- Correspondence: (E.A.V.-B.); (A.R.C.); Tel.: +55-(11)-3091-7246 (A.R.C.)
| |
Collapse
|
2
|
Vilas-Boas EA, Carlein C, Nalbach L, Almeida DC, Ampofo E, Carpinelli AR, Roma LP, Ortis F. Early Cytokine-Induced Transient NOX2 Activity Is ER Stress-Dependent and Impacts β-Cell Function and Survival. Antioxidants (Basel) 2021; 10:antiox10081305. [PMID: 34439552 PMCID: PMC8389306 DOI: 10.3390/antiox10081305] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 08/13/2021] [Accepted: 08/15/2021] [Indexed: 01/23/2023] Open
Abstract
In type 1 diabetes (T1D) development, proinflammatory cytokines (PIC) released by immune cells lead to increased reactive oxygen species (ROS) production in β-cells. Nonetheless, the temporality of the events triggered and the role of different ROS sources remain unclear. Isolated islets from C57BL/6J wild-type (WT), NOX1 KO and NOX2 KO mice were exposed to a PIC combination. We show that cytokines increase O2•− production after 2 h in WT and NOX1 KO but not in NOX2 KO islets. Using transgenic mice constitutively expressing a genetically encoded compartment specific H2O2 sensor, we show, for the first time, a transient increase of cytosolic/nuclear H2O2 in islet cells between 4 and 5 h during cytokine exposure. The H2O2 increase coincides with the intracellular NAD(P)H decrease and is absent in NOX2 KO islets. NOX2 KO confers better glucose tolerance and protects against cytokine-induced islet secretory dysfunction and death. However, NOX2 absence does not counteract the cytokine effects in ER Ca2+ depletion, Store-Operated Calcium Entry (SOCE) increase and ER stress. Instead, the activation of ER stress precedes H2O2 production. As early NOX2-driven ROS production impacts β-cells’ function and survival during insulitis, NOX2 might be a potential target for designing therapies against early β-cell dysfunction in the context of T1D onset.
Collapse
Affiliation(s)
- Eloisa A. Vilas-Boas
- Center for Human and Molecular Biology (ZHMB), Department of Biophysics, Saarland University, 66424 Homburg, Germany; (E.A.V.-B.); (C.C.)
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, SP, Brazil;
| | - Christopher Carlein
- Center for Human and Molecular Biology (ZHMB), Department of Biophysics, Saarland University, 66424 Homburg, Germany; (E.A.V.-B.); (C.C.)
| | - Lisa Nalbach
- Institute for Clinical and Experimental Surgery, Saarland University, 66424 Homburg, Germany; (L.N.); (E.A.)
| | - Davidson C. Almeida
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, SP, Brazil;
| | - Emmanuel Ampofo
- Institute for Clinical and Experimental Surgery, Saarland University, 66424 Homburg, Germany; (L.N.); (E.A.)
| | - Angelo R. Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, SP, Brazil;
| | - Leticia P. Roma
- Center for Human and Molecular Biology (ZHMB), Department of Biophysics, Saarland University, 66424 Homburg, Germany; (E.A.V.-B.); (C.C.)
- Correspondence: (L.P.R.); (F.O.); Tel.: +06841-16-16240 (L.P.R.); +55-(11)-3091-0923 (F.O.); Fax: +06841-16-16302 (L.P.R.)
| | - Fernanda Ortis
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo 05508-000, SP, Brazil;
- Correspondence: (L.P.R.); (F.O.); Tel.: +06841-16-16240 (L.P.R.); +55-(11)-3091-0923 (F.O.); Fax: +06841-16-16302 (L.P.R.)
| |
Collapse
|
3
|
Gomes PRL, Vilas-Boas EA, Leite EDA, Munhoz AC, Lucena CF, Amaral FGD, Carpinelli AR, Cipolla-Neto J. Melatonin regulates maternal pancreatic remodeling and B-cell function during pregnancy and lactation. J Pineal Res 2021; 71:e12717. [PMID: 33460489 DOI: 10.1111/jpi.12717] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 12/16/2020] [Accepted: 01/07/2021] [Indexed: 01/23/2023]
Abstract
The endocrine pancreas of pregnant rats shows evident plasticity, which allows the morphological structures to return to the nonpregnant state right after delivery. Furthermore, it is well-known the role of melatonin in the maintenance of the endocrine pancreas and its tropism. Studies indicate increasing nocturnal serum concentrations of maternal melatonin during pregnancy in both humans and rodents. The present study investigated the role of melatonin on energy metabolism and in pancreatic function and remodeling during pregnancy and early lactation in rats. The results confirm that the absence of melatonin during pregnancy impairs glucose metabolism. In addition, there is a dysregulation in insulin secretion at various stages of the development of pregnancy and an apparent failure in the glucose-stimulated insulin secretion during the lactation period, evidencing the role of melatonin on the regulation of insulin secretion. This mechanism seems not to be dependent on the antioxidant effect of melatonin and probably dependent on MT2 receptors. We also observed changes in the mechanisms of death and cell proliferation at the end of pregnancy and beginning of lactation, crucial periods for pancreatic remodeling. The present observations strongly suggest that both functionality and remodeling of the endocrine pancreas are impaired in the absence of melatonin and its adequate replacement, mimicking the physiological increase seen during pregnancy, is able to reverse some of the damage observed. Thus, we conclude that pineal melatonin is important to metabolic adaptation to pregnancy and both the functionality of the beta cells and the remodeling of the pancreas during pregnancy and early lactation, ensuring the return to nonpregnancy conditions.
Collapse
Affiliation(s)
| | - Eloisa Aparecida Vilas-Boas
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Eduardo de Almeida Leite
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Ana Cláudia Munhoz
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - Camila Ferraz Lucena
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | | | - Angelo Rafael Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| | - José Cipolla-Neto
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil
| |
Collapse
|
4
|
Nunes Marsiglio-Librais G, Aparecida Vilas-Boas E, Carlein C, Hoffmann MDA, Roma LP, Carpinelli AR. Evidence for NADPH oxidase activation by GPR40 in pancreatic β-cells. Redox Rep 2021; 25:41-50. [PMID: 32354273 PMCID: PMC7241480 DOI: 10.1080/13510002.2020.1757877] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Objective: Investigate the involvement of the fatty acids receptor GPR40 in the assembly and activation of NADPH oxidase and the implications on pancreatic β-cell function. Methods: BRIN-BD11 β-cells were exposed to GPR40 agonist (GW9508) or linoleic acid in different glucose concentrations. Superoxide and H2O2 were analyzed, respectively, by DHE fluorescence and by fluorescence of the H2O2 sensor, roGFP2-Orp1. Protein contents of p47phox in plasma membrane and cytosol were analyzed by western blot. NADPH oxidase role was evaluated by p22phox siRNA or by pharmacological inhibition with VAS2870. NOX2 KO islets were used to measure total cytosolic calcium and insulin secretion. Results: GW9508 and linoleic acid increased superoxide and H2O2 contents at 5.6 and 8.3 mM of glucose. In addition, in 5.6 mM, but not at 16.7 mM of glucose, activation of GPR40 led to the translocation of p47phox to the plasma membrane. Knockdown of p22phox abolished the increase in superoxide after GW9508 and linoleic acid. No differences in insulin secretion were found between wild type and NOX2 KO islets treated with GW9508 or linoleic acid. Discussion: We report for the first time that acute activation of GPR40 leads to NADPH oxidase activation in pancreatic β-cells, without impact on insulin secretion.
Collapse
Affiliation(s)
| | - Eloisa Aparecida Vilas-Boas
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, Brazil.,Department of Biophysics, Center for Human and Molecular Biology, CIPMM, Saarland University, Homburg/Saar, Germany
| | - Christopher Carlein
- Department of Biophysics, Center for Human and Molecular Biology, CIPMM, Saarland University, Homburg/Saar, Germany
| | | | - Leticia Prates Roma
- Department of Biophysics, Center for Human and Molecular Biology, CIPMM, Saarland University, Homburg/Saar, Germany
| | - Angelo Rafael Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, Brazil
| |
Collapse
|
5
|
Oxidative Stress in Cytokine-Induced Dysfunction of the Pancreatic Beta Cell: Known Knowns and Known Unknowns. Metabolites 2020; 10:metabo10120480. [PMID: 33255484 PMCID: PMC7759861 DOI: 10.3390/metabo10120480] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/18/2020] [Accepted: 11/21/2020] [Indexed: 12/12/2022] Open
Abstract
Compelling evidence from earlier studies suggests that the pancreatic beta cell is inherently weak in its antioxidant defense mechanisms to face the burden of protecting itself against the increased intracellular oxidative stress following exposure to proinflammatory cytokines. Recent evidence implicates novel roles for nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Noxs) as contributors to the excessive intracellular oxidative stress and damage under metabolic stress conditions. This review highlights the existing evidence on the regulatory roles of at least three forms of Noxs, namely Nox1, Nox2, and Nox4, in the cascade of events leading to islet beta cell dysfunction, specifically under the duress of chronic exposure to cytokines. Potential crosstalk between key signaling pathways (e.g., inducible nitric oxide synthase [iNOS] and Noxs) in the generation and propagation of reactive molecules and metabolites leading to mitochondrial damage and cell apoptosis is discussed. Available data accrued in investigations involving small-molecule inhibitors and antioxidant protein expression methods as tools toward the prevention of cytokine-induced oxidative damage are reviewed. Lastly, current knowledge gaps in this field, and possible avenues for future research are highlighted.
Collapse
|
6
|
Urner S, Ho F, Jha JC, Ziegler D, Jandeleit-Dahm K. NADPH Oxidase Inhibition: Preclinical and Clinical Studies in Diabetic Complications. Antioxid Redox Signal 2020; 33:415-434. [PMID: 32008354 DOI: 10.1089/ars.2020.8047] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Significance: Oxidative stress plays a critical role in the development and progression of serious micro- and macrovascular complications of diabetes. Nicotinamide adenine dinucleotide phosphate oxidase (NOX)-derived reactive oxygen species (ROS) significantly contribute to oxidative stress-associated inflammatory pathways that lead to tissue damage of different organs, including the kidneys, retina, brain, nerves, and the cardiovascular system. Recent Advances: Preclinical studies, including genetic-modified mouse models or cell culture models, have revealed the role of specific NOX isoforms in different diabetic complications, and suggested them as a promising target for the treatment of these diseases. Critical Issues: In this review, we provide an overview of the role of ROS and oxidative stress in macrovascular complications, such as stroke, myocardial infarction, coronary artery disease, and peripheral vascular disease that are all mainly driven by atherosclerosis, as well as microvascular complications, such as diabetic retinopathy, nephropathy, and neuropathy. We summarize conducted genetic deletion studies of different Nox isoforms as well as pharmacological intervention studies using NOX inhibitors in the context of preclinical as well as clinical research on diabetic complications. Future Directions: We outline the isoforms that are most promising for future clinical trials in the context of micro- and macrovascular complications of diabetes.
Collapse
Affiliation(s)
- Sofia Urner
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
| | - Florence Ho
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Jay C Jha
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Dan Ziegler
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
| | - Karin Jandeleit-Dahm
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University, Düsseldorf, Germany
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| |
Collapse
|
7
|
Bouzakri K, Veyrat-Durebex C, Holterman C, Arous C, Barbieux C, Bosco D, Altirriba J, Alibashe M, Tournier BB, Gunton JE, Mouche S, Bietiger W, Forterre A, Berney T, Pinget M, Christofori G, Kennedy C, Szanto I. Beta-Cell-Specific Expression of Nicotinamide Adenine Dinucleotide Phosphate Oxidase 5 Aggravates High-Fat Diet-Induced Impairment of Islet Insulin Secretion in Mice. Antioxid Redox Signal 2020; 32:618-635. [PMID: 31931619 DOI: 10.1089/ars.2018.7579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Aims: Nicotinamide adenine dinucleotide phosphate oxidases (NOX-es) produce reactive oxygen species and modulate β-cell insulin secretion. Islets of type 2 diabetic subjects present elevated expression of NOX5. Here, we sought to characterize regulation of NOX5 expression in human islets in vitro and to uncover the relevance of NOX5 in islet function in vivo using a novel mouse model expressing NOX5 in doxycycline-inducible, β-cell-specific manner (RIP/rtTA/NOX5 mice). Results:In situ hybridization and immunohistochemistry employed on pancreatic sections demonstrated NOX5 messenger ribonucleic acid (mRNA) and protein expressions in human islets. In cultures of dispersed islets, NOX5 protein was observed in somatostatin-positive (δ) cells in basal (2.8 mM glucose) conditions. Small interfering ribonucleic acid (siRNA)-mediated knockdown of NOX5 in human islets cultured in basal glucose concentrations resulted in diminished glucose-induced insulin secretion (GIIS) in vitro. However, when islets were preincubated in high (16.7 mM) glucose media for 12 h, NOX5 appeared also in insulin-positive (β) cells. In vivo, mice with β-cell NOX5 expression developed aggravated impairment of GIIS compared with control mice when challenged with 14 weeks of high-fat diet. Similarly, in vitro palmitate preincubation resulted in more severe reduction of insulin release in islets of RIP/rtTA/NOX5 mice compared with their control littermates. Decreased insulin secretion was most distinct in response to theophylline stimulation, suggesting impaired cyclic adenosine monophosphate (cAMP)-mediated signaling due to increased phosphodiesterase activation. Innovation and Conclusions: Our data provide the first insight into the complex regulation and function of NOX5 in islets implying an important role for NOX5 in δ-cell-mediated intraislet crosstalk in physiological circumstances but also identifying it as an aggravating factor in β-cell failure in diabetic conditions.
Collapse
Affiliation(s)
- Karim Bouzakri
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.,Centre Européen d'Etude du Diabète, Strasbourg, France
| | | | - Chet Holterman
- Division of Nephrology, Department of Medicine, Kidney Research Centre, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Caroline Arous
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.,Department of Cellular Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Charlotte Barbieux
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Domenico Bosco
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Jordi Altirriba
- Laboratory of Metabolism, Department of Internal Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Mohamed Alibashe
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Benjamin B Tournier
- Vulnerability Biomarkers Unit, Division of General Psychiatry, Department of Psychiatry, University Hospitals of Geneva, Geneva, Switzerland
| | - Jenny E Gunton
- Centre for Diabetes, Obesity and Endocrinology, Westmead Millennium Institute, The University of Sydney, Sydney, Australia.,Diabetes and Transcription Factors Group, Garvan Institute of Medical Research, Sydney, Australia
| | - Sarah Mouche
- Department of Cellular Physiology and Metabolism, University of Geneva, Geneva, Switzerland.,Department of Internal Medicine, Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | | | | | - Thierry Berney
- Division of Transplantation, Department of Surgery, University Hospitals of Geneva, Geneva, Switzerland
| | - Michel Pinget
- Centre Européen d'Etude du Diabète, Strasbourg, France
| | | | - Christopher Kennedy
- Division of Nephrology, Department of Medicine, Kidney Research Centre, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Ildiko Szanto
- Department of Internal Medicine, Geneva University Hospitals and University of Geneva, Geneva, Switzerland.,Diabetes Center of the Faculty of Medicine at the University of Geneva, Geneva, Switzerland
| |
Collapse
|
8
|
Shen X, Luo L, Yang M, Lin Y, Li J, Yang L. Exendin‑4 inhibits lipotoxicity‑induced oxidative stress in β‑cells by inhibiting the activation of TLR4/NF‑κB signaling pathway. Int J Mol Med 2020; 45:1237-1249. [PMID: 32124969 DOI: 10.3892/ijmm.2020.4490] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 12/02/2019] [Indexed: 11/05/2022] Open
Abstract
The present study aimed to investigate the relationship between the protective effects of exendin‑4 (EX‑4) on lipotoxicity‑induced oxidative stress and meta‑inflammation in β‑cells and the toll‑like receptor 4 (TLR4)/NF‑κB signaling pathway. Lipotoxicity, hydrogen peroxide (H2O2)‑induced oxidative stress in β cells, obese Sprague Dawley rats and TLR4 truncation rats were utilized in the present study. The expression levels were detected by western blotting; cell apoptosis was detected by TUNEL assay; and the intracellular reactive oxygen species (ROS) levels were analyzed using a ROS assay kit. The findings of the present study showed that EX‑4 inhibited the expression of TLR4, NF‑κB p65 subunit and p47phox in a concentration‑dependent manner, and decreased the intracellular level of ROS. Additionally, silencing of TLR4 expression enhanced the protective effects of EX‑4, while overexpression of TLR4 attenuated these protective influences. Simultaneously, it was demonstrated that TLR4 was involved in the process of EX‑4 intervention to inhibit H2O2‑induced oxidative stress in islet β‑cells. Moreover, it was found that EX‑4 also inhibited TLR4‑ or NF‑κB agonist‑induced oxidative stress. These results were also confirmed in an animal model of obese rats, in which EX‑4 was able to improve the function of β‑cells, attenuate oxidative stress, and inhibit the expression levels of TLR4 and NF‑κB p65 subunit in the pancreas of the diet‑induced obese rats. Furthermore, truncation of the TLR4 gene in SD rats delayed the aforementioned damage. In summary, EX‑4 may inhibit lipotoxicity‑induced oxidative stress in β‑cells by inhibiting the activation of the TLR4/NF‑κB signaling pathway.
Collapse
Affiliation(s)
- Ximei Shen
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Liufen Luo
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Meng Yang
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Yuxi Lin
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Jing Li
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Liyong Yang
- Endocrinology Department, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| |
Collapse
|
9
|
Pharmacological stimulation of NQO1 decreases NADPH levels and ameliorates acute pancreatitis in mice. Cell Death Dis 2018; 10:5. [PMID: 30584237 PMCID: PMC6315021 DOI: 10.1038/s41419-018-1252-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 11/28/2018] [Accepted: 12/03/2018] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) regulates the activation of inflammatory cascades and tissue damage in acute pancreatitis. NADPH oxidase (NOX) is upregulated in pancreatitis and is one of the major enzymes involved in ROS production using NADPH as a general rate-limiting substrate. Dunnione, a well-known substrate of NAD(P)H:quinone oxidoreductase 1 (NQO1), reduces the ratio of cellular NADPH/NADP+ through the enzymatic action of NQO1. This study assessed whether a reduction in cellular NADPH/NADP+ ratio can be used to regulate caerulein-induced pancreatic damage associated with NOX-induced ROS production in animal models. Dunnione treatment significantly reduced the cellular NADPH/NADP+ ratio and NOX activity through the enzymatic action of NQO1 in the pancreas of the caerulein-injection group. Similar to these results, total ROS production and expressions of mRNA and protein for NOX subunits Nox1, p27phox, p47phox, and p67phox also decreased in the dunnione-treated group. In addition, caerulein-induced pancreatic inflammation and acinar cell injury were significantly reduced by dunnione treatment. This study is the first to demonstrate that modulation of the cellular NADPH:NADP+ ratio by enzymatic action of NQO1 protects acute pancreatitis through the regulation of NOX activity. Furthermore, these results suggest that modulation of the NADPH:NADP+ ratio in cells by NQO1 may be a novel therapeutic strategy for acute pancreatitis.
Collapse
|
10
|
Wang X, Elksnis A, Wikström P, Walum E, Welsh N, Carlsson PO. The novel NADPH oxidase 4 selective inhibitor GLX7013114 counteracts human islet cell death in vitro. PLoS One 2018; 13:e0204271. [PMID: 30265686 PMCID: PMC6161897 DOI: 10.1371/journal.pone.0204271] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/04/2018] [Indexed: 01/11/2023] Open
Abstract
It has been proposed that pancreatic beta-cell dysfunction in type 2 diabetes is promoted by oxidative stress caused by NADPH oxidase (Nox) over-activity. The aim of the present study was to evaluate the efficacy of novel Nox inhibitors as protective agents against cytokine- or high glucose + palmitate-induced human beta-cell death. The Nox2 protein was present mainly in the cytoplasm and was induced by cytokines. Nox4 protein immunoreactivity, with some nuclear accumulation, was observed in human islet cells, and was not affected by islet culture in the presence of cytokines or high glucose + palmitate. Nox inhibitors with partial or no isoform selectivity (DPI, dapsone, GLX351322, and GLX481372) all reduced ROS production of human islet cells exposed to high glucose + palmitate. This was paralleled by improved viability and reduced caspase 3 activation. The Nox1 selective inhibitor ML171 failed to reduce human islet cell death in response to both cytokines and high glucose + palmitate. The selective Nox2 inhibitor Phox-I2 also failed to protect against cytokines, but protected partially against high glucose + palmitate-induced cellular death. The highly selective Nox4 inhibitor GLX7013114 protected islet cells against both cytokines and high glucose + palmitate. However, as no osmotic control for high glucose was used, we cannot exclude the possibility that the high glucose effect was due to osmosis. It is concluded that Nox4 may participate in stress-induced islet cell death in human islets in vitro. We propose that Nox4 mediates pro-apoptotic effects in intact islets under stressful conditions and that selective Nox4-inhibition may be a therapeutic strategy in type 2 diabetes.
Collapse
Affiliation(s)
- Xuan Wang
- Science for Life Laboratory, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- * E-mail:
| | - Andris Elksnis
- Science for Life Laboratory, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | | | - Nils Welsh
- Science for Life Laboratory, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- Science for Life Laboratory, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| |
Collapse
|
11
|
Simões D, Riva P, Peliciari-Garcia RA, Cruzat VF, Graciano MF, Munhoz AC, Taneda M, Cipolla-Neto J, Carpinelli AR. Melatonin modifies basal and stimulated insulin secretion via NADPH oxidase. J Endocrinol 2016; 231:235-244. [PMID: 27803236 DOI: 10.1530/joe-16-0259] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 10/04/2016] [Indexed: 01/10/2023]
Abstract
Melatonin is a hormone synthesized in the pineal gland, which modulates several functions within the organism, including the synchronization of glucose metabolism and glucose-stimulated insulin secretion (GSIS). Melatonin can mediate different signaling pathways in pancreatic islets through two membrane receptors and via antioxidant or pro-oxidant enzymes modulation. NADPH oxidase (NOX) is a pro-oxidant enzyme responsible for the production of the reactive oxygen specie (ROS) superoxide, generated from molecular oxygen. In pancreatic islets, NOX-derived ROS can modulate glucose metabolism and regulate insulin secretion. Considering the roles of both melatonin and NOX in islets, the aim of this study was to evaluate the association of NOX and ROS production on glucose metabolism, basal and GSIS in pinealectomized rats (PINX) and in melatonin-treated isolated pancreatic islets. Our results showed that ROS content derived from NOX activity was increased in PINX at baseline (2.8 mM glucose), which was followed by a reduction in glucose metabolism and basal insulin secretion in this group. Under 16.7 mM glucose, an increase in both glucose metabolism and GSIS was observed in PINX islets, without changes in ROS content. In isolated pancreatic islets from control animals incubated with 2.8 mM glucose, melatonin treatment reduced ROS content, whereas in 16.7 mM glucose, melatonin reduced ROS and GSIS. In conclusion, our results demonstrate that both basal and stimulated insulin secretion can be regulated by melatonin through the maintenance of ROS homeostasis in pancreatic islets.
Collapse
Affiliation(s)
- Daniel Simões
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Patrícia Riva
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Rodrigo Antonio Peliciari-Garcia
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
- Department of Biological SciencesLaboratory of Biosystems, Federal University of São Paulo, Diadema, São Paulo, Brazil
| | - Vinicius Fernandes Cruzat
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Maria Fernanda Graciano
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Ana Claudia Munhoz
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Marco Taneda
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - José Cipolla-Neto
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| | - Angelo Rafael Carpinelli
- Department of Physiology and BiophysicsInstitute of Biomedical Sciences-I, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
12
|
Deng W, Abliz A, Xu S, Sun R, Guo W, Shi Q, Yu J, Wang W. Severity of pancreatitis‑associated intestinal mucosal barrier injury is reduced following treatment with the NADPH oxidase inhibitor apocynin. Mol Med Rep 2016; 14:3525-34. [PMID: 27573037 PMCID: PMC5042780 DOI: 10.3892/mmr.2016.5678] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/17/2016] [Indexed: 02/06/2023] Open
Abstract
Recent studies demonstrated that apocynin, a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) inhibitor, significantly decreased acute pancreatitis-associated inflammatory and oxidative stress parameters. In addition, apocynin was able to reduce ischemic reperfusion injury-associated damage; however, the exact effects of apocynin on acute pancreatitis-associated intestinal mucosal injury have yet to be fully clarified. The present study aimed to investigate the protective effects of apocynin on intestinal mucosal injury in a rat model of severe acute pancreatitis (SAP). A total of 60 male Sprague Dawley rats were randomly divided into four groups (n=15/group): Sham operation group (SO), SAP group, apocynin treatment (APO) group and drug control (APO-CON) group. SAP was induced by retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. Apocynin was administered 30 min prior to SAP induction in the APO group. All rats were sacrificed 12 h after SAP induction. Intestinal integrity was assessed by measuring diamine oxidase (DAO) levels. Morphological alterations to intestinal tissue were determined under light and transmission electron microscopy. NOX2, p38 mitogen-activated protein kinases (MAPK) and nuclear factor (NF)-κB expression levels were detected in the intestine by immunohistochemical staining. Oxidative stress was detected by measuring intestinal malondialdehyde (MDA) and superoxide dismutase content. In addition, blood inflammatory cytokines, and amylase (AMY) and lipase (LIP) levels were evaluated. The results demonstrated that apocynin attenuated the following: i) Serum AMY, LIP and DAO levels; ii) pancreatic and intestinal pathological injury; iii) intestinal MDA content; iv) intestinal ultrastructural alterations; v) serum interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α levels; and vi) NOX2, p38 MAPK and NF-κB expression in intestinal tissues. These results suggested that apocynin may attenuate intestinal barrier dysfunction in sodium taurocholate-induced SAP, presumably via its role in the prevention of reactive oxygen species generation and inhibition of p38 MAPK and NF-κB pathway activation. These findings provide novel insight suggesting that pharmacological inhibition of NOX by apocynin may be considered a novel therapeutic method for the treatment of intestinal injury in SAP.
Collapse
Affiliation(s)
- Wenhong Deng
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Ablikim Abliz
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Sheng Xu
- Department of General Surgery, People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, Guangxi 530021, P.R. China
| | - Rongze Sun
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Wenyi Guo
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Qiao Shi
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Jia Yu
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Weixing Wang
- Department of General Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| |
Collapse
|
13
|
Munhoz AC, Riva P, Simões D, Curi R, Carpinelli AR. Control of Insulin Secretion by Production of Reactive Oxygen Species: Study Performed in Pancreatic Islets from Fed and 48-Hour Fasted Wistar Rats. PLoS One 2016; 11:e0158166. [PMID: 27362938 PMCID: PMC4928816 DOI: 10.1371/journal.pone.0158166] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 06/07/2016] [Indexed: 11/19/2022] Open
Abstract
Mitochondria and NADPH oxidase are important sources of reactive oxygen species in particular the superoxide radical (ROS) in pancreatic islets. These molecules derived from molecular oxygen are involved in pancreatic β-cells signaling and control of insulin secretion. We examined the involvement of ROS produced through NADPH oxidase in the leucine- and/or glucose-induced insulin secretion by pancreatic islets from fed or 48-hour fasted rats. Glucose-stimulated insulin secretion (GSIS) in isolated islets was evaluated at low (2.8 mM) or high (16.7 mM) glucose concentrations in the presence or absence of leucine (20 mM) and/or NADPH oxidase inhibitors (VAS2870–20 μM or diphenylene iodonium—DPI—5 μM). ROS production was determined in islets treated with dihydroethidium (DHE) or MitoSOX Red reagent for 20 min and dispersed for fluorescence measurement by flow cytometry. NADPH content variation was examined in INS-1E cells (an insulin secreting cell line) after incubation in the presence of glucose (2.8 or 16.7 mM) and leucine (20 mM). At 2.8 mM glucose, VAS2870 and DPI reduced net ROS production (by 30%) and increased GSIS (by 70%) in a negative correlation manner (r = -0.93). At 16.7 mM glucose or 20 mM leucine, both NADPH oxidase inhibitors did not alter insulin secretion neither net ROS production. Pentose phosphate pathway inhibition by treatment with DHEA (75 μM) at low glucose led to an increase in net ROS production in pancreatic islets from fed rats (by 40%) and induced a marked increase (by 144%) in islets from 48-hour fasted rats. The NADPH/NADP+ ratio was increased when INS-1E cells were exposed to high glucose (by 4.3-fold) or leucine (by 3-fold). In conclusion, increased ROS production through NADPH oxidase prevents the occurrence of hypoglycemia in fasting conditions, however, in the presence of high glucose or high leucine levels, the increased production of NADPH and the consequent enhancement of the activity of the antioxidant defenses mitigate the excess of ROS production and allow the secretory process of insulin to take place.
Collapse
Affiliation(s)
- Ana Cláudia Munhoz
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
- * E-mail:
| | - Patrícia Riva
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Daniel Simões
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Angelo Rafael Carpinelli
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
14
|
Bułdak Ł, Łabuzek K, Bułdak RJ, Machnik G, Bołdys A, Basiak M, Bogusław O. Metformin reduces the expression of NADPH oxidase and increases the expression of antioxidative enzymes in human monocytes/macrophages cultured in vitro. Exp Ther Med 2016; 11:1095-1103. [PMID: 26998043 DOI: 10.3892/etm.2016.2977] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 09/25/2015] [Indexed: 01/08/2023] Open
Abstract
The treatment of diabetes and its complications is a key challenge for healthcare professionals. Accelerated atherosclerosis is associated with progressive diabetes, and it has been indicated that macrophages serve a crucial function in this process. Currently, the first-line treatment of diabetes is based on metformin, which is an inducer of AMP-activated protein kinase (AMPK) and belongs to the biguanide class of pharmaceuticals. It has been previously demonstrated that metformin exhibits more than just hypoglycemic effects. Therefore, the aim of the present study was to investigate the in vitro impact of metformin on cell viability and the expression levels of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase (p22phox), a major enzyme in reactive oxygen species generation, and the three antioxidative enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) in monocytes/macrophages derived from 10 healthy volunteers. The effects of metformin were observed in the presence or absence of lipopolysaccharide (LPS), which was administered to induce oxidative stress. Furthermore, certain cells were treated with compound C, an inhibitor of AMPK, in order to determine the mechanistic role played by AMPK in the oxidative changes in the macrophages. Cell viability was evaluated using trypan blue and MTT assays. The mRNA and protein expression levels of p22phox and the various antioxidative enzymes were determined using polymerase chain reaction and western blot analysis, respectively. The results indicated that metformin, predominantly in LPS-pretreated monocytes/macrophages, reduced the expression levels of p22phox and increased those of SOD and GPx, but had only a minor effect on CAT levels. Therefore, metformin appears to alter the oxidative status of macrophages toward increasingly antioxidative activity, which may account for the pleiotropic effects observed during metformin treatment.
Collapse
Affiliation(s)
- Łukasz Bułdak
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Krzysztof Łabuzek
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Rafał Jakub Bułdak
- Department of Physiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Zabrze 41-808, Poland
| | - Grzegorz Machnik
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Aleksandra Bołdys
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Marcin Basiak
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Okopień Bogusław
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| |
Collapse
|
15
|
Anvari E, Wikström P, Walum E, Welsh N. The novel NADPH oxidase 4 inhibitor GLX351322 counteracts glucose intolerance in high-fat diet-treated C57BL/6 mice. Free Radic Res 2015; 49:1308-18. [DOI: 10.3109/10715762.2015.1067697] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|
16
|
Abstract
OBJECTIVES The aim of the study was to evaluate the potential changes induced by fish oil (FO) supplementation on the redox status of pancreatic islets from healthy rats. To test whether these effects were due to eicosapentaenoic acid and docosahexaenoic acid (ω-3), in vitro experiments were performed. METHODS Rats were supplemented with FO, and pancreatic islets were obtained. Islets were also treated in vitro with palmitate (P) or eicosapentaenoic acid + docosahexaenoic acid (ω-3). Insulin secretion (GSIS), glucose oxidation, protein expression, and superoxide content were analyzed. RESULTS The FO group showed a reduction in superoxide content. Moreover, FO reduced the expression of NAD(P)H oxidase subunits and increased superoxide dismutase, without altering β-cell function. Palmitate increased β-cell reactive oxygen species (ROS) production, apoptosis, and impaired GSIS. Under these conditions, ω-3 triggered a parallel reduction in ROS production and β-cell apoptosis induced by P and protected against the impairment in GSIS. There was no difference in mitochondrial ROS production. CONCLUSIONS Our results show that ω-3 protect pancreatic islets from alterations induced by P. In vivo FO supplementation modulates the redox state of pancreatic β-cell. Considering that in vitro effects do not involve mitochondrial superoxide production, we can speculate that this protection might involve NAD(P)H oxidase activity.
Collapse
|
17
|
Weaver JR, Grzesik W, Taylor-Fishwick DA. Inhibition of NADPH oxidase-1 preserves beta cell function. Diabetologia 2015; 58:113-21. [PMID: 25277953 DOI: 10.1007/s00125-014-3398-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 09/09/2014] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS Upregulation of the reactive oxygen species (ROS)-producing enzyme NADPH oxidase (NOX)-1 in islets and beta cells follows acute exposure to inflammatory cytokines and is concomitant with beta cell dysfunction. NOX-1 is a candidate mediator of inflammation-induced beta cell dysfunction. This study aimed to determine whether selective inhibition of NADPH oxidase-1 presents a new strategy to preserve beta cell function. METHODS Induced beta cell dysfunction was studied in primary human donor islets, isolated mouse islets and murine beta cell lines. Islets and beta cells were stimulated with inflammatory cytokines (TNF-α, IL-1β, IFN-γ). NOX-1 activity was blocked by the selective inhibitor ML171. RESULTS Cytokine induction of intracellular ROS was reduced 80% with 1 μmol/l ML171 in murine beta cell lines (p < 0.01). Cytokine-induced apoptosis, measured by caspase-3 activation or quantified fluorescence microscopy, was prevented in islets and beta cell lines up to 100% with ML171 in a concentration-dependent manner (p < 0.05). Functionally, glucose-stimulated insulin secretion was abolished by cytokine exposure but preserved by ML171 in isolated mouse islets and murine beta cell lines. A feed-forward regulation of NOX-1 in islets and beta cell lines was disrupted by ML171. CONCLUSIONS/INTERPRETATION Stimulation of NOX-1 activity is a major component of inflammatory cytokine-induced beta cell dysfunction. Significant protection of beta cells is conferred with selective inhibition of NOX-1. Suppression of NOX-1 activity may present a new therapeutic strategy to preserve and protect beta cell function in diabetes.
Collapse
Affiliation(s)
- Jessica R Weaver
- Department of Microbiology and Molecular Cell Biology, LH 2128, Eastern Virginia Medical School, 700 W. Olney Road, Norfolk, VA, 23507, USA
| | | | | |
Collapse
|
18
|
Cao WL, Xiang XH, Chen K, Xu W, Xia SH. Potential role of NADPH oxidase in pathogenesis of pancreatitis. World J Gastrointest Pathophysiol 2014; 5:169-177. [PMID: 25133019 PMCID: PMC4133516 DOI: 10.4291/wjgp.v5.i3.169] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 03/25/2014] [Accepted: 06/16/2014] [Indexed: 02/06/2023] Open
Abstract
Studies have demonstrated that reactive oxygen species (ROS) are closely related to inflammatory disorders. Nicotinamide adenine dinucleotide phosphate oxidase (NOX), originally found in phagocytes, is the main source of ROS in nonphagocytic cells. Besides directly producing the detrimental highly reactive ROS to act on biomolecules (lipids, proteins, and nucleic acids), NOX can also activate multiple signal transduction pathways, which regulate cell growth, proliferation, differentiation and apoptosis by producing ROS. Recently, research on pancreatic NOX is no longer limited to inflammatory cells, but extends to the aspect of pancreatic acinar cells and pancreatic stellate cells, which are considered to be potentially associated with pancreatitis. In this review, we summarize the literature on NOX protein structure, activation, function and its role in the pathogenesis of pancreatitis.
Collapse
|
19
|
Broniowska KA, Mathews CE, Corbett JA. Do β-cells generate peroxynitrite in response to cytokine treatment? J Biol Chem 2013; 288:36567-78. [PMID: 24194521 DOI: 10.1074/jbc.m113.522243] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The purpose of this study was to determine the reactive species that is responsible for cytokine-mediated β-cell death. Inhibitors of inducible nitric oxide synthase prevent this death, and addition of exogenous nitric oxide using donors induces β-cell death. The reaction of nitric oxide with superoxide results in the generation of peroxynitrite, and this powerful oxidant has been suggested to be the mediator of β-cell death in response to cytokine treatment. Recently, coumarin-7-boronate has been developed as a probe for the selective detection of peroxynitrite. Using this reagent, we show that addition of the NADPH oxidase activator phorbol 12-myristate 13-acetate to nitric oxide-producing macrophages results in peroxynitrite generation. Using a similar approach, we demonstrate that cytokines fail to stimulate peroxynitrite generation by rat islets and insulinoma cells, either with or without phorbol 12-myristate 13-acetate treatment. When forced to produce superoxide using redox cyclers, this generation is associated with protection from nitric oxide toxicity. These findings indicate that: (i) nitric oxide is the likely mediator of the toxic effects of cytokines, (ii) β-cells do not produce peroxynitrite in response to cytokines, and (iii) when forced to produce superoxide, the scavenging of nitric oxide by superoxide is associated with protection of β-cells from nitric oxide-mediated toxicity.
Collapse
Affiliation(s)
- Katarzyna A Broniowska
- From the Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and
| | | | | |
Collapse
|
20
|
Huang A, Zhang B, Wang B, Zhang F, Fan KX, Guo YJ. Increased CD14(+)HLA-DR (-/low) myeloid-derived suppressor cells correlate with extrathoracic metastasis and poor response to chemotherapy in non-small cell lung cancer patients. Cancer Immunol Immunother 2013; 62:1439-51. [PMID: 23760662 PMCID: PMC11028777 DOI: 10.1007/s00262-013-1450-6] [Citation(s) in RCA: 166] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 06/04/2013] [Indexed: 01/21/2023]
Abstract
Accumulating evidence has demonstrated that myeloid-derived suppressor cells (MDSCs), a heterogeneous population of cells, play an important role in the subversion, inhibition, and downregulation of the immune response to cancer. However, the characteristics of these cells, particularly clinical relevance, in malignant tumors remain unclear due to a lack of specific markers. In this study, we characterized peripheral CD14(+)HLA-DR(-/low) cells, a new human MDSC subpopulation, in 89 patients with non-small cell lung cancer (NSCLC). As expected, both frequency and absolute number of CD14(+)HLA-DR(-/low) cells were significantly increased in the peripheral blood of NSCLC patients compared with that of the healthy controls and indicated an association with metastasis, response to chemotherapy, and progression-free survival. These cells showed decreased expression of CD16 and CD86 compared with HLA-DR(+) monocytes. Unlike classical monocytes, these populations showed significantly decreased allostimulatory activity and showed the ability to inhibit autologous T cell proliferation and IFN-γ production in a cell-contact-dependent manner. Furthermore, we demonstrated that CD14(+)HLA-DR(-/low) cells expressed the NADPH oxidase component gp91(phox) and generated high level of reactive oxygen species (ROS). Moreover, inactivation of ROS reversed their immunosuppressive capacity on T cell response. These results prove, for the first time, the existence of ROS-producing CD14(+)HLA-DR(-/low) myeloid-derived suppressor cells in NSCLC patients, which mediate tumor immunosuppression and might thus represent a potential target for therapeutic intervention.
Collapse
Affiliation(s)
- Ang Huang
- Cancer Center, Chinese PLA General Hospital, Beijing, 100853 People’s Republic of China
- Department of Infectious Diseases, Beijing 302 Hospital, Beijing, 100039 People’s Republic of China
| | - Bo Zhang
- International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, New Building West 10-11th Floor, Shanghai, 200433 People’s Republic of China
| | - Bo Wang
- Cancer Center, Chinese PLA General Hospital, Beijing, 100853 People’s Republic of China
| | - Fan Zhang
- Cancer Center, Chinese PLA General Hospital, Beijing, 100853 People’s Republic of China
| | - Ke-Xing Fan
- Cancer Center, Chinese PLA General Hospital, Beijing, 100853 People’s Republic of China
- International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, New Building West 10-11th Floor, Shanghai, 200433 People’s Republic of China
| | - Ya-Jun Guo
- Cancer Center, Chinese PLA General Hospital, Beijing, 100853 People’s Republic of China
- International Joint Cancer Institute, The Second Military Medical University, 800 Xiang Yin Road, New Building West 10-11th Floor, Shanghai, 200433 People’s Republic of China
| |
Collapse
|
21
|
Jayaram B, Kowluru A. Phagocytic NADPH oxidase links ARNO-Arf6 signaling pathway in glucose-stimulated insulin secretion from the pancreatic β-cell. Cell Physiol Biochem 2012; 30:1351-62. [PMID: 23095975 DOI: 10.1159/000343324] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/09/2012] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Recent findings from our laboratory have demonstrated that glucose-stimulated insulin secretion (GSIS) involves interplay between a variety of small G proteins belonging to the Rho (e.g., Cdc42 and Rac1) and ADP-ribosylation factor (e.g., Arf6) subfamilies. Using immunological, pharmacological and molecular biological approaches, we have also identified guanine nucleotide exchange factors (GEFs) for Rac1 (e.g., Tiam1) and Arf6 (e.g., ARNO) in clonal INS-1 832/13 cells, normal rat islets and human islets. As a logical extension to these studies, we investigated, herein, potential downstream signaling steps involved in Arf6/ARNO-mediated GSIS. METHODS Using a selective pharmacological inhibitor of ARNO/Arf6 signaling axis (e.g., secinH3) we assessed regulatory roles for Arf6/ARNO in promoting phospholipase D (PLD), phagocytic NADPH oxidase (Nox2), reactive oxygen species (ROS), extracellular-regulated kinases (ERK 1/2) and cofilin (actin-severing protein] signaling steps in clonal INS-1 832/13 cells. RESULTS Our data suggested a marked inhibition by secinH3 of glucose-induced PLD activation, ERK1/2 phosphorylation and dephosphorylation of cofilin, suggesting that Arf6/ ARNO signaling mediates PLD, ERK1/2 and cofilin activation in beta-cells. In addition, secinH3 blocked glucose-induced Nox2 activation and associated ROS generation, thus placing Nox downstream to Arf6/ARNO signaling step. Lastly, we also demonstrate a significantly higher cofilin phosphorylation (inactive) in islets derived from type 2 diabetic human donors as well as the Zucker Diabetic Fatty (ZDF) rat, a model for type 2 diabetes. CONCLUSION Together, our current findings identify signaling steps downstream to ARNO/Arf6 axis leading to insulin secretion.
Collapse
Affiliation(s)
- Bhavaani Jayaram
- Beta-Cell Biochemistry Laboratory, John D. Dingell VA Medical Center and Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA
| | | |
Collapse
|