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Salvator H, Grassin-Delyle S, Naline E, Brollo M, Fournier C, Couderc LJ, Devillier P. Contrasting Effects of Adipokines on the Cytokine Production by Primary Human Bronchial Epithelial Cells: Inhibitory Effects of Adiponectin. Front Pharmacol 2020; 11:56. [PMID: 32132922 PMCID: PMC7040162 DOI: 10.3389/fphar.2020.00056] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 01/22/2020] [Indexed: 12/15/2022] Open
Abstract
Background Obesity is associated with an elevated risk of respiratory infections and inflammatory lung diseases. The objective was to investigate (i) the effects of adipokines (adiponectin (APN), leptin, chemerin, and visfatin) on the production of cytokines by unstimulated and poly(I:C)- and TNF-α-activated human primary bronchial epithelial cells (hBECs), (ii) the cells’ expression of the APN receptors (AdipoR1 and AdipoR2), and (iii) the cells' production of APN. Methods The hBECs were isolated from patients undergoing surgery for lung carcinoma. The cells were then cultured with human recombinant adipokines in the absence or presence of TNF-α or poly(I:C) for 24 h. Supernatant levels of cytokines (IL-6, CCL2, CCL5, CCL20, CXCL1, CXCL8) and APN were measured using ELISAs. The mRNA levels of AdipoR1 and AdipoR2 in hBECs were determined using a real-time quantitative PCR. Results Of the four adipokines tested, only APN significantly influenced the basal production and the TNF-α poly(I:C)-induced production of cytokines by hBECs. APN (3-30 µg.ml-1) was associated with greater basal production of IL-6, CCL20, and CXCL8, lower basal production of CCL2 and CXCL1 and no difference in CCL5 production. APN inhibited the poly(I:C)-induced production of these five cytokines and the TNF-α-induced production of CCL2 and CXCL1. AdipoR1 and AdipoR2 were both expressed in hBECs. In contrast to human bronchial explants, isolated hBECs did not produce APN. Conclusions The APN concentrations are abnormally low in obese individuals, and this fall may contribute to the susceptibility to viral lung infections and the severity of these infections in obese individuals.
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Affiliation(s)
- Hélène Salvator
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France.,Department of Respiratory Diseases, Hôpital Foch, Suresnes, France
| | - Stanislas Grassin-Delyle
- Department of Respiratory Diseases, Hôpital Foch, Suresnes, France.,Mass Spectrometry Platform & INSERM UMR1173, UFR Sciences de la Santé Simone Veil, Université Versailles Saint Quentin en Yvelines, Université Paris-Saclay, Montigny-le-Bretonneux, France
| | - Emmanuel Naline
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France.,Department of Respiratory Diseases, Hôpital Foch, Suresnes, France
| | - Marion Brollo
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France
| | - Caroline Fournier
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France
| | - Louis-Jean Couderc
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France.,Department of Respiratory Diseases, Hôpital Foch, Suresnes, France
| | - Philippe Devillier
- Laboratory of Research in Respiratory Pharmacology-UPRES EA220, UFR Sciences de la Santé Simone Veil, Université Paris-Saclay, Suresnes, France.,Department of Respiratory Diseases, Hôpital Foch, Suresnes, France
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2
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Oita RC, Camp SM, Ma W, Ceco E, Harbeck M, Singleton P, Messana J, Sun X, Wang T, Garcia JGN. Novel Mechanism for Nicotinamide Phosphoribosyltransferase Inhibition of TNF-α-mediated Apoptosis in Human Lung Endothelial Cells. Am J Respir Cell Mol Biol 2019; 59:36-44. [PMID: 29337590 DOI: 10.1165/rcmb.2017-0155oc] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Nicotinamide phosphoribosyltransferase (NAMPT) exists as both intracellular NAMPT and extracellular NAMPT (eNAMPT) proteins. eNAMPT is secreted into the blood and functions as a cytokine/enzyme (cytozyme) that activates NF-κB signaling via ligation of Toll-like receptor 4 (TLR4), further serving as a biomarker for inflammatory lung disorders such as acute respiratory distress syndrome. In contrast, intracellular NAMPT is involved in nicotinamide mononucleotide synthesis and has been implicated in the regulation of cellular apoptosis, although the exact mechanisms for this regulation are poorly understood. We examined the role of NAMPT in TNF-α-induced human lung endothelial cell (EC) apoptosis and demonstrated that reduced NAMPT expression (siRNA) increases EC susceptibility to TNF-α-induced apoptosis as reflected by PARP-1 cleavage and caspase-3 activation. In contrast, overexpression of NAMPT served to reduce degrees of TNF-α-induced EC apoptosis. Inhibition of nicotinamide mononucleotide synthesis by FK866 (a selective NAMPT enzymatic inhibitor) failed to alter TNF-α-induced human lung EC apoptosis, suggesting that NAMPT-dependent NAD+ generation is unlikely to be involved in regulation of TNF-α-induced EC apoptosis. We next confirmed that TNF-α-induced EC apoptosis is attributable to NAMPT secretion into the EC culture media and subsequent eNAMPT ligation of TLR4 on the EC membrane surface. Silencing of NAMPT expression, direct neutralization of secreted eNAMPT by an NAMPT-specific polyclonal antibody (preventing TLR4 ligation), or direct TLR4 antagonism all served to significantly increase EC susceptibility to TNF-α-induced EC apoptosis. Together, these studies provide novel insights into NAMPT contributions to lung inflammatory events and to novel mechanisms of EC apoptosis regulation.
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Affiliation(s)
- Radu C Oita
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Sara M Camp
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Wenli Ma
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Ermelinda Ceco
- 2 Institute for Personalized Respiratory Medicine, University of Illinois at Chicago, Chicago, Illinois; and
| | - Mark Harbeck
- 2 Institute for Personalized Respiratory Medicine, University of Illinois at Chicago, Chicago, Illinois; and
| | | | - Joe Messana
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Xiaoguang Sun
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Ting Wang
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
| | - Joe G N Garcia
- 1 Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Health Sciences, University of Arizona, Tucson, Arizona
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3
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Essential Role of Visfatin in Lipopolysaccharide and Colon Ascendens Stent Peritonitis-Induced Acute Lung Injury. Int J Mol Sci 2019; 20:ijms20071678. [PMID: 30987270 PMCID: PMC6480124 DOI: 10.3390/ijms20071678] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 03/22/2019] [Accepted: 03/27/2019] [Indexed: 12/21/2022] Open
Abstract
Acute lung injury (ALI) is a life-threatening syndrome characterized by acute and severe hypoxemic respiratory failure. Visfatin, which is known as an obesity-related cytokine with pro-inflammatory activities, plays a role in regulation of inflammatory cytokines. The mechanisms of ALI remain unclear in critically ill patients. Survival in ALI patients appear to be influenced by the stress generated by mechanical ventilation and by ALI-associated factors that initiate the inflammatory response. The objective for this study was to understand the mechanisms of how visfatin regulates inflammatory cytokines and promotes ALI. The expression of visfatin was evaluated in ALI patients and mouse sepsis models. Moreover, the underlying mechanisms were investigated using human bronchial epithelial cell lines, BEAS-2B and NL-20. An increase of serum visfatin was discovered in ALI patients compared to normal controls. Results from hematoxylin and eosin (H&E) and immunohistochemistry staining also showed that visfatin protein was upregulated in mouse sepsis models. Moreover, lipopolysaccharide (LPS) induced visfatin expression, activated the STAT3/NFκB pathway, and increased the expression of pro-inflammatory cytokines, including IL1-β, IL-6, and TNF-α in human bronchial epithelial cell lines NL-20 and BEAS-2B. Co-treatment of visfatin inhibitor FK866 reversed the activation of the STAT3/NFκB pathway and the increase of pro-inflammatory cytokines induced by LPS. Our study provides new evidence for the involvement of visfatin and down-stream events in acute lung injury. Further studies are required to confirm whether the anti-visfatin approaches can improve ALI patient survival by alleviating the pro-inflammatory process.
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4
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Bi G, Wu L, Huang P, Islam S, Heruth DP, Zhang LQ, Li DY, Sampath V, Huang W, Simon BA, Easley RB, Ye SQ. Up-regulation of SFTPB expression and attenuation of acute lung injury by pulmonary epithelial cell-specific NAMPT knockdown. FASEB J 2018; 32:3583-3596. [PMID: 29452569 PMCID: PMC5998971 DOI: 10.1096/fj.201701059r] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 01/22/2018] [Indexed: 12/11/2022]
Abstract
Although a deficiency of surfactant protein B (SFTPB) has been associated with lung injury, SFTPB expression has not yet been linked with nicotinamide phosphoribosyltransferase (NAMPT), a potential biomarker of acute lung injury (ALI). The effects of Nampt in the pulmonary epithelial cell on both SFTPB expression and lung inflammation were investigated in a LPS-induced ALI mouse model. Pulmonary epithelial cell-specific knockdown of Nampt gene expression, achieved by the crossing of Nampt gene exon 2 floxed mice with mice expressing epithelial-specific transgene Cre or by the use of epithelial-specific expression of anti-Nampt antibody cDNA, significantly attenuated LPS-induced ALI. Knockdown of Nampt expression was accompanied by lower levels of bronchoalveolar lavage (BAL) neutrophil infiltrates, total protein and TNF-α levels, as well as lower lung injury scores. Notably, Nampt knockdown was also associated with significantly increased BAL SFTPB levels relative to the wild-type control mice. Down-regulation of NAMPT increased the expression of SFTPB and rescued TNF-α-induced inhibition of SFTPB, whereas overexpression of NAMPT inhibited SFTPB expression in both H441 and A549 cells. Inhibition of NAMPT up-regulated SFTPB expression by enhancing histone acetylation to increase its transcription. Additional data indicated that these effects were mainly mediated by NAMPT nonenzymatic function via the JNK pathway. This study shows that pulmonary epithelial cell-specific knockdown of NAMPT expression attenuated ALI, in part, via up-regulation of SFTPB expression. Thus, epithelial cell-specific knockdown of Nampt may be a potential new and viable therapeutic modality to ALI.-Bi, G., Wu, L., Huang, P., Islam, S., Heruth, D. P., Zhang, L. Q., Li, D.-Y., Sampath, V., Huang, W., Simon, B. A., Easley, R. B., Ye, S. Q. Up-regulation of SFTPB expression and attenuation of acute lung injury by pulmonary epithelial cell-specific NAMPT knockdown.
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Affiliation(s)
- Guangliang Bi
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
- Department of Neonatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Lei Wu
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
- Department of Pediatrics, Changsha Central Hospital, Changsha, China
| | - Peixin Huang
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Shamima Islam
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Daniel P. Heruth
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Li Qin Zhang
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Ding-You Li
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Venkatesh Sampath
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
| | - Weimin Huang
- Department of Neonatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Brett A. Simon
- Department of Anesthesiology, Josie Robertson Surgery Center, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, Cornell University, New York, New York, USA
| | - Ronald Blaine Easley
- Department of Pediatrics-Anesthesiology, Baylor College of Medicine, Houston, Texas, USA
| | - Shui Qing Ye
- Department of Pediatrics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
- Department of Biomedical and Health Informatics, Children’s Mercy, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, USA
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5
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He JY, Cui HJ, Tang LJ, Chen J, Huang WM. Inhibition of pre-B cell colony-enhancing factor attenuates inflammation induced by hyperoxia in EA.hy926 cells. Int J Mol Med 2017; 40:859-866. [DOI: 10.3892/ijmm.2017.3045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 06/09/2017] [Indexed: 11/06/2022] Open
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6
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Huang P, Lee MW, Sadrerafi K, Heruth DP, Zhang LQ, Maulik D, Ye SQ. MC-PPEA as a new and more potent inhibitor of CLP-induced sepsis and pulmonary inflammation than FK866. DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:629-641. [PMID: 28424540 PMCID: PMC5344436 DOI: 10.2147/dddt.s125349] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Our previous study indicated that overexpression of nicotinamide phosphoribosyltransferase (NAMPT) aggravated acute lung injury, while knockdown of NAMPT expression attenuated ventilator-induced lung injury. Recently, we found that meta-carborane-butyl-3-(3-pyridinyl)-2E-propenamide (MC-PPEA, MC4), in which the benzoylpiperidine moiety of FK866 has been replaced by a carborane, displayed a 100-fold increase in NAMPT inhibition over FK866. Here, we determined the effects of MC4 and FK866 on cecal ligation and puncture (CLP) surgery-induced sepsis in C57BL/6J mice. MC4 showed stronger inhibitory effects than FK866 on CLP-induced mortality, serum tumor necrosis factor α (TNFα) levels, pulmonary myeloperoxidase activity, alveolar injury, and interleukin 6 and interleukin1β messenger RNA levels. In vitro cell permeability and electric cell-substrate impedance sensing assays demonstrated that MC4 inhibited TNFα- and thrombin-mediated pulmonary endothelial cell permeability better than FK866. MC4 also exerted more potent effects than FK866, at concentrations as low as 0.3 nM, to attenuate TNFα-mediated intracellular cytokine expression, nicotinamide adenine dinucleotide (NAD+) and its reduced form NADH levels, and nuclear factor kappa B p65 phosphorylation and nuclear translocation in A549 cells. Our results strongly suggest that the newly developed MC4 is a more potent suppressor of CLP-induced pulmonary inflammation and sepsis than FK866, with potential clinical application as a new treatment agent for sepsis and inflammation.
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Affiliation(s)
- Peixin Huang
- Division of Experimental and Translational Genetics, Department of Pediatrics, The Children's Mercy Hospital, University of Missouri Kansas City School of Medicine Kansas City
| | - Mark W Lee
- Department of Chemistry, University of Missouri, Columbia, MO
| | | | - Daniel P Heruth
- Division of Experimental and Translational Genetics, Department of Pediatrics, The Children's Mercy Hospital, University of Missouri Kansas City School of Medicine Kansas City
| | - Li Q Zhang
- Division of Experimental and Translational Genetics, Department of Pediatrics, The Children's Mercy Hospital, University of Missouri Kansas City School of Medicine Kansas City
| | - Dev Maulik
- Department of Biomedical and Health Informatics, University of Missouri Kansas City School of Medicine.,Department of Obstetrics and Gynecology, Truman Medical Center, Kansas City, MO, USA
| | - Shui Qing Ye
- Division of Experimental and Translational Genetics, Department of Pediatrics, The Children's Mercy Hospital, University of Missouri Kansas City School of Medicine Kansas City.,Department of Obstetrics and Gynecology, Truman Medical Center, Kansas City, MO, USA
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7
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Chen X, Zhao S, Song Y, Shi Y, Leak RK, Cao G. The Role of Nicotinamide Phosphoribosyltransferase in Cerebral Ischemia. Curr Top Med Chem 2016; 15:2211-21. [PMID: 26059356 DOI: 10.2174/1568026615666150610142234] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 01/30/2015] [Accepted: 04/20/2015] [Indexed: 12/18/2022]
Abstract
As recombinant tissue plasminogen activator is the only drug approved for the clinical treatment of acute ischemic stroke, there is an urgent unmet need for novel stroke treatments. Endogenous defense mechanisms against stroke may hold the key to new therapies for stroke. A large number of studies suggest that nicotinamide phosphoribosyl-transferase (NAMPT is an attractive candidate to improve post-stroke recovery. NAMPT is a multifunctional protein and plays important roles in immunity, metabolism, aging, inflammation, and stress responses. NAMPT exists in both the intracellular and extracellular space. As a rate-limiting enzyme, the intracellular form (iNAMPT catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide (NAD from nicotinamide. iNAMPT closely regulates energy metabolism, enhancing the proliferation of endothelial cells, inhibiting apoptosis, regulating vascular tone, and stimulating autophagy in disease conditions such as stroke. Extracellular NAMPT (eNAMPT is also known as visfatin (visceral fat-derived adipokine and has pleotropic effects. It is widely believed that the diverse biological functions of eNAMPT are attributed to its NAMPT enzymatic activity. However, the effects of eNAMPT on ischemic injury are still controversial. Some authors have argued that eNAMPT exacerbates ischemic neuronal injury non-enzymatically by triggering the release of TNF-α from glial cells. In addition, NAMPT also participates in several pathophysiological processes such as hypertension, atherosclerosis, and ischemic heart disease. Thus, it remains unclear under what conditions NAMPT is beneficial or destructive. Recent work using in vitro and in vivo genetic/ pharmacologic manipulations, including our own studies, has greatly improved our understanding of NAMPT. This review focuses on the multifaceted and complex roles of NAMPT under both normal and ischemic conditions.
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Affiliation(s)
- Xinzhi Chen
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA.
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8
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Ming GF, Ma XH, Xu DM, Liu ZY, Ai YH, Liu HX, Shi ZH. PBEF promotes the apoptosis of pulmonary microvascular endothelial cells and regulates the expression of inflammatory factors and AQP1 through the MAPK pathways. Int J Mol Med 2015; 36:890-6. [PMID: 26178576 DOI: 10.3892/ijmm.2015.2283] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 07/07/2015] [Indexed: 11/05/2022] Open
Abstract
Pre-B cell colony-enhancing factor (PBEF) has been shown to have a variety of biological functions. Studies have proven that PBEF plays a functional role in acute lung injury (ALI). Therefore, in this study, we aimed to confirm the importance of PBEF in ALI. The effects of PBEF overexpression on the apoptosis of human pulmonary microvascular endothelial cells (HPMECs) were analyzed by flow cytometry, and the results indicated that PBEF promoted the apoptosis of HPMECs, which aggravated the development of ALI. Comparative experiments involving increasing and decreasing PBEF expression demonstrated that PBEF promoted the expression of inflammatory factors, such as interleukin (IL)‑1β, IL‑6 and IL‑8 in the HPMECs , thus intensifying the inflammatory response. PBEF also inhibited the expression of aquaporin 1 (AQP1), which caused a dysfunction and imbalance in water transport. Moreover, we also found that tumor necrosis factor (TNF)‑α promoted the expression of PBEF in the HPMECs. After blocking the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways, we found that PBEF regulated the expression of inflammatory factors and AQP1, mainly through the MAPK pathways. Taken together, these results demonstrate that the increase in intracellular PBEF expression promoted the apoptosis of HPMECs and the expression of inflammatory factors and thus enhanced the inflammatory response and inhibited the expression of AQP1, which resulted in abnormal water transport, diminishing the regulatory effects of AQP1 on water transport.
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Affiliation(s)
- Guang-Feng Ming
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Xin-Hua Ma
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Dao-Miao Xu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Zhi-Yong Liu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Yu-Hang Ai
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Hui-Xia Liu
- Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Zan-Hua Shi
- Department of Neurosurgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
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9
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Lee JO, Kim N, Lee HJ, Lee YW, Kim JK, Kim HI, Lee SK, Kim SJ, Park SH, Kim HS. Visfatin, a novel adipokine, stimulates glucose uptake through the Ca2 +-dependent AMPK-p38 MAPK pathway in C2C12 skeletal muscle cells. J Mol Endocrinol 2015; 54:251-62. [PMID: 26019302 DOI: 10.1530/jme-14-0274] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Visfatin is a novel adipocytokine produced by visceral fat. In the present study, visfatin increased AMP-activated protein kinase (AMPK) phosphorylation in mouse C2C12 skeletal muscle cells. It also increased phosphorylation of the insulin receptor, whose knockdown blocked visfatin-induced AMPK phosphorylation and glucose uptake. Visfatin stimulated glucose uptake in differentiated skeletal muscle cells. However, inhibition of AMPKα2 with an inhibitor or with knockdown of AMPKα2 using siRNA blocked visfatin-induced glucose uptake, which indicates that visfatin stimulates glucose uptake through the AMPKα2 pathway. Visfatin increased the intracellular Ca(2) (+) concentration. STO-609, a calmodulin-dependent protein kinase kinase inhibitor, blocked visfatin-induced AMPK phosphorylation and glucose uptake. Visfatin-mediated activation of p38 MAPK was AMPKα2-dependent. Furthermore, both inhibition and knockdown of p38 MAPK blocked visfatin-induced glucose uptake. Visfatin increased glucose transporter type 4 (GLUT4) mRNA and protein levels. In addition, visfatin stimulated the translocation of GLUT4 to the plasma membrane, and this effect was suppressed by AMPKα2 inhibition. The present results indicate that visfatin plays an important role in glucose metabolism via the Ca(2) (+)-mediated AMPK-p38 MAPK pathway.
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Affiliation(s)
- Jung Ok Lee
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Nami Kim
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Hye Jeong Lee
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Yong Woo Lee
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Joong Kwan Kim
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Hyung Ip Kim
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Soo Kyung Lee
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Su Jin Kim
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Sun Hwa Park
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
| | - Hyeon Soo Kim
- Department of Anatomy Korea University College of Medicine, 126-1, Anam-dong 5-ga, Seongbuk-gu, Seoul, Korea
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10
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Matsuda A, Yang WL, Jacob A, Aziz M, Matsuo S, Matsutani T, Uchida E, Wang P. FK866, a visfatin inhibitor, protects against acute lung injury after intestinal ischemia-reperfusion in mice via NF-κB pathway. Ann Surg 2014; 259:1007-17. [PMID: 24169192 DOI: 10.1097/sla.0000000000000329] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine whether administration of FK866, a competitive inhibitor of visfatin, attenuates acute lung injury induced by intestinal ischemia-reperfusion (I/R). BACKGROUND Acute lung injury, a frequent complication of intestinal I/R, is an inflammatory disorder of the lung, which is characterized by an overproduction of proinflammatory cytokines and increased permeability of the alveolar-capillary barrier, resulting in multiple organ dysfunction. Therefore, the development of novel and effective therapies for intestinal I/R is critical for the improvement of patient outcome. Visfatin, a 54-kDa secretory protein, is known as a proinflammatory cytokine and plays a deleterious role in inflammatory diseases. METHODS Male C57BL/6J mice were subjected to intestinal I/R induced by occlusion of the superior mesenteric artery for 90 minutes, followed by reperfusion. During reperfusion period, mice were treated with vehicle or FK866 (10 mg/kg of body weight) by an intraperitoneal injection. The levels of visfatin, proinflammatory mediators, and other markers were assessed 4 hours after reperfusion. In addition, survival study was conducted in intestinal I/R mice with or without FK866 treatment. RESULTS Plasma and lung visfatin protein levels were significantly increased after intestinal I/R. FK866 treatment significantly attenuated intestinal and lung injury by inhibiting proinflammatory cytokine production, cellular apoptosis, and NF-κB activation, hence improving survival rate. In vitro studies showed that macrophages treated with lipopolysaccharides upregulated visfatin expression, whereas FK866 inhibited proinflammatory cytokine production via modulation of the NF-κB pathway. CONCLUSIONS Collectively, these findings implicate FK866 as a novel therapeutic compound for intestinal I/R-induced attenuates acute lung injury via modulation of innate immune functions.
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Affiliation(s)
- Akihisa Matsuda
- *Department of Surgery, Hofstra North Shore-LIJ School of Medicine and Center for Translational Research, The Feinstein Institute for Medical Research, Manhasset, NY †Department of Surgery, Nippon Medical School, Tokyo, Japan
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11
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Adyshev DM, Elangovan VR, Moldobaeva N, Mapes B, Sun X, Garcia JGN. Mechanical stress induces pre-B-cell colony-enhancing factor/NAMPT expression via epigenetic regulation by miR-374a and miR-568 in human lung endothelium. Am J Respir Cell Mol Biol 2014; 50:409-18. [PMID: 24053186 DOI: 10.1165/rcmb.2013-0292oc] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Increased lung vascular permeability and alveolar edema are cardinal features of inflammatory conditions such as acute respiratory distress syndrome (ARDS) and ventilator-induced lung injury (VILI). We previously demonstrated that pre-B-cell colony-enhancing factor (PBEF)/NAMPT, the proinflammatory cytokine encoded by NAMPT, participates in ARDS and VILI inflammatory syndromes. The present study evaluated posttranscriptional regulation of PBEF/NAMPT gene expression in human lung endothelium via 3'-untranslated region (UTR) microRNA (miRNA) binding. In silico analysis identified hsa-miR-374a and hsa-miR-568 as potential miRNA candidates. Increased PBEF/NAMPT transcription (by RT-PCR) and expression (by Western blotting) induced by 18% cyclic stretch (CS) (2 h: 3.4 ± 0.06 mRNA fold increase (FI); 10 h: 1.5 ± 0.06 protein FI) and by LPS (4 h: 3.8 ± 0.2 mRNA FI; 48 h: 2.6 ± 0.2 protein FI) were significantly attenuated by transfection with mimics of hsa-miR-374a or hsa-miR-568 (40-60% reductions each). LPS and 18% CS increased the activity of a PBEF/NAMPT 3'-UTR luciferase reporter (2.4-3.25 FI) with induction reduced by mimics of each miRNA (44-60% reduction). Specific miRNA inhibitors (antagomirs) for each PBEF/NAMPT miRNA significantly increased the endogenous PBEF/NAMPT mRNA (1.4-3.4 ± 0.1 FI) and protein levels (1.2-1.4 ± 0.1 FI) and 3'-UTR luciferase activity (1.4-1.7 ± 0.1 FI) compared with negative antagomir controls. Collectively, these data demonstrate that increased PBEF/NAMPT expression induced by bioactive agonists (i.e., excessive mechanical stress, LPS) involves epigenetic regulation with hsa-miR-374a and hsa-miR-568, representing novel therapeutic strategies to reduce inflammatory lung injury.
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Affiliation(s)
- Djanybek M Adyshev
- Institute for Personalized Respiratory Medicine, Department of Medicine, Section of Pulmonary, Critical Care, Sleep, and Allergy, University of Illinois at Chicago, Chicago, Illinois
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Sun Z, Lei H, Zhang Z. Pre-B cell colony enhancing factor (PBEF), a cytokine with multiple physiological functions. Cytokine Growth Factor Rev 2013; 24:433-42. [PMID: 23787158 DOI: 10.1016/j.cytogfr.2013.05.006] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 05/12/2013] [Accepted: 05/21/2013] [Indexed: 02/07/2023]
Abstract
Pre-B cell colony enhancing factor (PBEF) is regarded as a proinflammatory cytokine. Named for its first discovered function as a pre-B cell colony enhancing factor, it has since been found to have many other functions relating to cell metabolism, inflammation, and immune modulation. It has also been found to have intracellular and extracellular forms, with the two overlapping in function. Most of the intracellular functions of PBEF are due to its role as a nicotinamide phosphoribosyltransferase (Nampt). It has been found in human endothelial cells, where it is able to induce angiogenesis through upregulation of VEGF and VEGFR and secretion of MCP-1. In human umbilical endothelial cells, PBEF increases levels of the protease MMP 2/9. PBEF has also been found in a variety of immune cells other than B cells and has been shown to inhibit apoptosis of macrophages. Extracellular PBEF has been shown to increase inflammatory cytokines, such as TNF-α, IL-1β, IL-16, and TGF-β1, and the chemokine receptor CCR3. PBEF also increases the production of IL-6, TNF-α, and IL-1β in CD14(+) monocyctes, macrophages, and dendritic cells, enhances the effectiveness of T cells, and is vital to the development of both B and T lymphocytes. The purpose of this review is to summarize the recent advances in PBEF research.
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Affiliation(s)
- Zhongjie Sun
- Department of Physiology, College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA; Department of Cardiology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China.
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Abstract
Nicotinamide phosphoribosyltransferase is the rate-limiting enzyme that catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide from nicotinamide. This protein was originally cloned as a putative pre-B cell colony-enhancing factor and also found to be a visceral fat-derived adipokine (visfatin). As a multifunctional protein, visfatin plays an important role in immunity, metabolism, aging, inflammation, and responses to stress. Visfatin also participates in several pathophysiological processes contributing to cardio-cerebro-vascular diseases, including hypertension, atherosclerosis, ischemic heart disease, and ischemic stroke. However, whether visfatin is a friend or a foe in these diseases remains uncertain. This brief review focuses on the current understanding of the complex role of visfatin in the cardio-cerebro-vascular system under normal and pathophysiological conditions.
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Affiliation(s)
- Pei Wang
- Department of Pharmacology, Second Military Medical University, Shanghai, China
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14
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Inflammatory markers and bariatric surgery: a meta-analysis. Inflamm Res 2012; 61:789-807. [DOI: 10.1007/s00011-012-0473-3] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 02/27/2012] [Accepted: 03/19/2012] [Indexed: 12/11/2022] Open
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Bi J, Li H, Ye SQ, Ding S. Pre-B-cell colony-enhancing factor exerts a neuronal protection through its enzymatic activity and the reduction of mitochondrial dysfunction in in vitro ischemic models. J Neurochem 2011; 120:334-46. [PMID: 22044451 DOI: 10.1111/j.1471-4159.2011.07566.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Pre-B-cell colony-enhancing factor (PBEF) is known as a rate-limiting enzyme that converts nicotinamide (NAM) to NMN in the salvage pathway of mammalian NAD⁺ biosynthesis. Previously we found PBEF is exclusively expressed in neurons in the mouse brain; heterozygous PBEF knockout (Pbef⁺/⁻) mice have larger ischemic lesion than wild type mice in photothrombosis-induced ischemia. For the mechanistic study of neuronal protective role of PBEF, we used in vitro oxygen-glucose deprivation (OGD) and glutamate excitotoxicity models of primary cultured neurons in current study. Our results showed that the treatments of neurons with NAM and NAD⁺, the substrate and downstream product of PBEF, respectively, significantly reduced neuronal death after OGD and glutamate excitotoxicity, while treatment of neurons treated with FK866, a PBEF inhibitor, increased neuronal death after OGD. Furthermore, over-expression of human PBEF reduced glutamate excitotoxicity, while over-expression of human PBEF mutants (i.e. H247A and H247E) without enzymatic activity had no effect on neuronal death. We further tested the effect of PBEF on mitochondrial function and biogenesis. Our results show that addition of NAD⁺ and NAM increased mitochondrial biogenesis in neurons after OGD. Over-expression of PBEF in neurons reduced mitochondrial membrane potential depolarization following glutamate stimulation, while over-expression of H247A and H247E did not affect mitochondrial membrane potential depolarization. We conclude that PBEF has a neuroprotective effect in ischemia through its enzymatic activity for NAD⁺ production that can ameliorate mitochondrial dysfunction.
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Affiliation(s)
- Jing Bi
- Dalton Cardiovascular Research Center, University of Missouri-Columbia, Missouri 65211, USA
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Lee KA, Gong MN. Pre-B-cell colony-enhancing factor and its clinical correlates with acute lung injury and sepsis. Chest 2011; 140:382-390. [PMID: 21565968 PMCID: PMC3148796 DOI: 10.1378/chest.10-3100] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 04/13/2011] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Pre-B-cell colony-enhancing factor (PBEF) is a potential biomarker for acute lung injury (ALI) in sepsis. We aimed to determine the clinical correlates for elevated plasma PBEF upon ICU admission for severe sepsis and the usefulness of PBEF to predict ALI development and sepsis mortality. METHODS This is a prospective cohort of patients admitted to the medical ICU with severe sepsis. Patients without available blood samples or who were not enrolled within 24 h of admission were excluded. Plasma collected within 24 h of ICU admission was measured for PBEF concentrations by enzyme-linked immunosorbent assay. Patients were followed for ALI development as defined by the American-European Consensus Conference and for all-cause hospital mortality. RESULTS Between September 30, 2008, and March 10, 2009, 113 patients were enrolled, and 50 (44%) developed ALI. Elevated PBEF levels significantly correlated with higher APACHE (Acute Physiology and Chronic Health Evaluation) III scores (R(2) = 0.08, P = .003) and failure to reach early sepsis goals within 6 h of severe sepsis (P = .003). PBEF did not differ by ALI status (P = .58). The mortality rate was 46%. Nonsurvivors had higher PBEF levels than survivors (2.53 ng/mL; interquartile range [IQR], 1.07-8.16 vs 1.44 ng/mL; IQR, 0.84-2.81; P = .02). After adjusting for severity of illness, PBEF levels were no longer significantly associated with mortality (OR, 1.44 per 10-fold increase; 95% CI, 0.69-3.03, P = .34). CONCLUSIONS In this study, elevated PBEF did not correlate with lung injury in sepsis. However, it was associated with sepsis mortality mainly due to its association with greater severity of illness on ICU admission.
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Affiliation(s)
- Kathleen A Lee
- Department of Medicine, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI
| | - Michelle N Gong
- Division of Critical Care Medicine, Department of Medicine, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY.
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Besnard AG, Guillou N, Tschopp J, Erard F, Couillin I, Iwakura Y, Quesniaux V, Ryffel B, Togbe D. NLRP3 inflammasome is required in murine asthma in the absence of aluminum adjuvant. Allergy 2011; 66:1047-57. [PMID: 21443539 DOI: 10.1111/j.1398-9995.2011.02586.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Inflammasome activation with the production of IL-1β received substantial attention recently in inflammatory diseases. However, the role of inflammasome in the pathogenesis of asthma is not clear. Using an adjuvant-free model of allergic lung inflammation induced by ovalbumin (OVA), we investigated the role of NLRP3 inflammasome and related it to IL-1R1 signaling pathway. METHODS Allergic lung inflammation induced by OVA was evaluated in vivo in mice deficient in NLRP3 inflammasome, IL-1R1, IL-1β or IL-1α. Eosinophil recruitment, Th2 cytokine, and chemokine levels were determined in bronchoalveolar lavage fluid, lung homogenates, and mediastinal lymph node cells ex vivo. RESULTS Allergic airway inflammation depends on NLRP3 inflammasome activation. Dendritic cell recruitment into lymph nodes, Th2 lymphocyte activation in the lung and secretion of Th2 cytokines and chemokines are reduced in the absence of NLRP3. Absence of NLRP3 and IL-1β is associated with reduced expression of other proinflammatory cytokines such as IL-5, IL-13, IL-33, and thymic stromal lymphopoietin. Furthermore, the critical role of IL-1R1 signaling in allergic inflammation is confirmed in IL-1R1-, IL-1β-, and IL-1α-deficient mice. CONCLUSION NLRP3 inflammasome activation leading to IL-1 production is critical for the induction of a Th2 inflammatory allergic response.
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Affiliation(s)
- A-G Besnard
- Université d'Orléans and CNRS, Molecular Immunology and Embryology (IEM), Orléans, France
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Zhang LQ, Heruth DP, Ye SQ. Nicotinamide Phosphoribosyltransferase in Human Diseases. ACTA ACUST UNITED AC 2011; 3:13-25. [PMID: 22140607 DOI: 10.4172/1948-593x.1000038] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nicotinamide phosphoribosyltransferase (NAMPT) was first reported as a pre-B-cell colony enhancing factor in 1994 with little notice, but it has received increasing attention in recent years due to accumulating evidence indicating that NAMPT is a pleiotropic protein such as a growth factor, a cytokine, an enzyme and a visfatin. Now, NAMPT has been accepted as an official name of this protein. Because of NAMPT's multiple functions in a variety of physiological processes, their dysregulations have been implicated in the pathogenesis of a number of human diseases or conditions such as acute lung injury, aging, atherosclerosis, cancer, diabetes, rheumatoid arthritis and sepsis. This review will cover the current understanding of NAMPT's structure and functions with an emphasis on recent progress of nicotinamide phosphoribosyltransferase's pathological roles in various human diseases and conditions. Future directions on exploring its Terra incognita will be offered in the end.
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Affiliation(s)
- Li Qin Zhang
- Department of Pediatrics, Children's Mercy Hospitals and Clinics, University of Missouri School of Medicine, Kansas City, MO 64108, USA
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Grahnert A, Grahnert A, Klein C, Schilling E, Wehrhahn J, Hauschildt S. Review: NAD +: a modulator of immune functions. Innate Immun 2010; 17:212-33. [PMID: 20388721 DOI: 10.1177/1753425910361989] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Latterly, nicotinamide adenine dinucleotide (NAD+) has emerged as a molecule with versatile functions and of enormous impact on the maintenance of cell integrity. Besides playing key roles in almost all major aspects of energy metabolism, there is mounting evidence that NAD+ and its degradation products affect various biological activities including calcium homeostasis, gene transcription, DNA repair, and intercellular communication. This review is aimed at giving a brief insight into the life cycle of NAD+ in the cell, referring to synthesis, action and degradation aspects. With respect to their immunological relevance, the importance and function of the major NAD+ metabolizing enzymes, namely CD38/CD157, ADP-ribosyltransferases (ARTs), poly-ADP-ribose-polymerases (PARPs), and sirtuins are summarized and roles of NAD+ and its main degradation product adenosine 5'-diphosphoribose (ADPR) in cell signaling are discussed. In addition, an outline of the variety of immunological processes depending on the activity of nicotinamide phosphoribosyltransferase (Nampt), the key enzyme of the salvage pathway of NAD+ synthesis, is presented. Taken together, an efficient supply of NAD+ seems to be a crucial need for a multitude of cell functions, underlining the yet only partly revealed potency of this small molecule to influence cell fate.
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Affiliation(s)
- Andreas Grahnert
- Department of Immunobiology, Institute of Biology, University of Leipzig, Talstrasse 33, Leipzig, Germany
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Liu P, Li H, Cepeda J, Xia Y, Kempf JA, Ye H, Zhang LQ, Ye SQ. Regulation of inflammatory cytokine expression in pulmonary epithelial cells by pre-B-cell colony-enhancing factor via a nonenzymatic and AP-1-dependent mechanism. J Biol Chem 2009; 284:27344-51. [PMID: 19654329 DOI: 10.1074/jbc.m109.002519] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Although our previous studies found Pre-B-cell colony-enhancing factor (PBEF) as a highly up-regulated gene in acute lung injury that could stimulate expressions of other inflammatory cytokines, the underlying molecular mechanisms remain to be fully elucidated. Growing evidence indicates that PBEF is a nicotinamide phosphoribosyltransferase involved in the mammalian salvage pathway of NAD synthesis. This study was designed to determine whether the effect of PBEF to stimulate expressions of inflammatory cytokines depends on its enzymatic activity. We prepared two human PBEF mutant (H247E and H247A) recombinant proteins and overexpressing constructs for their overexpressions in A549 cells and confirmed that enzymatic activities of both mutants were nearly or completely abolished. Two mutants stimulated interleukin-8 (IL-8) expression at both the mRNA level and protein level just as equally effective as the wild-type PBEF did. These effects were due to the increased transcription, not the mRNA stability, of the IL-8 gene. Reporter gene assays and gel shift experiments indicated that AP-1 transcription factor is required to mediate these effects. SB203580, a p38 MAPK pathway inhibitor, and JNK inhibitor 1 can attenuate these effects. Both PBEF mutants similarly stimulated the expression of two other inflammatory cytokines: IL-16 and CCR3. These results indicate that PBEF stimulated expression of IL-8, IL-16, and CCR3 via its non-enzymatic activity. This effect is AP-1-dependent, in part via the p38 MAPK pathway and the JNK pathway. This finding reveals a new insight, which may manifest a novel role of PBEF in the pathogenesis of acute lung injury and other inflammatory disorders.
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Affiliation(s)
- Peng Liu
- Department of Surgery, University of Missouri, Columbia, Missouri 65212, USA
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