1
|
Priya Dharshini LC, Vishnupriya S, Sakthivel KM, Rasmi RR. Oxidative stress responsive transcription factors in cellular signalling transduction mechanisms. Cell Signal 2020; 72:109670. [PMID: 32418887 DOI: 10.1016/j.cellsig.2020.109670] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/06/2020] [Accepted: 05/06/2020] [Indexed: 11/18/2022]
Abstract
Oxidative stress results from the imbalances in the development of reactive oxygen species (ROS) and antioxidants defence system resulting in tissue injury. A key issue resulting in the modulation of ROS is that it alters hosts molecular, structural and functional properties which is accomplished via various signalling pathways which either activate or inhibit numerous transcription factors (TFs). Some of the regulators include Nuclear erythroid-2 related factors (Nrf-2), CCAAT/enhancer-binding protein delta (CEBPD), Activator Protein-1 (AP-1), Hypoxia-inducible factor 1(HIF-1), Nuclear factor κB (NF-κB), Specificity Protein-1 (SP-1) and Forkhead Box class O (FoxO) transcription factors. The expression of these transcription factors are dependent upon the stress signal and are sometimes interlinked. They are highly specific having their own regulation cellular events. Depending upon the transcription factors and better knowledge on the type of the oxidative stress help researchers develop safe, novel targets which can serve as efficient therapeutic targets for several disease conditions.
Collapse
Affiliation(s)
| | - Selvaraj Vishnupriya
- Department of Biotechnology, PSG College of Arts & Science, Civil Aerodrome Post, Coimbatore, Tamil Nadu 641 014, India
| | - Kunnathur Murugesan Sakthivel
- Department of Biochemistry, PSG College of Arts & Science, Civil Aerodrome Post, Coimbatore, Tamil Nadu 641 014, India
| | - Rajan Radha Rasmi
- Department of Biotechnology, PSG College of Arts & Science, Civil Aerodrome Post, Coimbatore, Tamil Nadu 641 014, India.
| |
Collapse
|
2
|
Hesperetin ameliorates lipopolysaccharide-induced acute lung injury in mice through regulating the TLR4-MyD88-NF-κB signaling pathway. Arch Pharm Res 2019; 42:1063-1070. [PMID: 31802426 DOI: 10.1007/s12272-019-01200-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 12/02/2019] [Indexed: 12/17/2022]
Abstract
Hesperetin, a major bioflavonoid in sweet oranges and lemons, exerts an anti-inflammatory effect in pulmonary diseases; however, its effect on lipopolysaccharide (LPS)-induced acute lung injury is unclear. This study investigated the effect of hesperetin on LPS-induced lung inflammatory response. Mice were intratracheally instilled with 5 mg/kg body weight LPS, and then were given hesperetin orally (10, 20, and 30 mg/kg body weight) 1 h later. Hesperetin dramatically suppressed the levels of interleukin-6 and tumor necrosis factor-α, as well as the number of inflammatory cells in bronchoalveolar lavage fluid. Besides, it reduced lung injury, wet weight/dry weight ratio, and myeloperoxidase and lactate dehydrogenase activities, and enhanced superoxide dismutase activity. In addition, hesperetin significantly downregulated the Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) protein expression and suppressed nuclear factor-kappa B (NF-κB) activation in lung tissue. Together, these results indicated that the anti-inflammatory effect of hesperetin is associated with the TLR4-MyD88-NF-κB pathway, and that hesperetin shows therapeutic potential for LPS-induced acute lung injury.
Collapse
|
3
|
Serebrovska Z, Swanson RJ, Portnichenko V, Shysh A, Pavlovich S, Tumanovska L, Dorovskych A, Lysenko V, Tertykh V, Bolbukh Y, Dosenko V. Anti-inflammatory and antioxidant effect of cerium dioxide nanoparticles immobilized on the surface of silica nanoparticles in rat experimental pneumonia. Biomed Pharmacother 2017; 92:69-77. [PMID: 28531802 DOI: 10.1016/j.biopha.2017.05.064] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 05/04/2017] [Accepted: 05/12/2017] [Indexed: 12/31/2022] Open
Abstract
A massage with the potent counter-inflammatory material, cerium dioxide nanoparticles, is promising and the antioxidant properties of CeO2 are considered the main, if not the only, mechanism of this action. Nevertheless, the elimination of ceria nano-particles from the organism is very slow and there is a strong concern for toxic effect of ceria due to its accumulation. To overcome this problem, we engineered a combined material in which cerium nanoparticles were immobilized on the surface of silica nanoparticles (CeO2 NP), which is shown to be easily removed from an organism and could be used as carriers for nano-ceria. In our study particle size was 220±5nm, Zeta-potential -4.5mV (in water), surface charge density -17.22μC/cm2 (at pH 7). Thirty-six male Wistar rats, 5 months old and 250-290g were divided into four groups: 1) control; 2) CeO2 NP treatment; 3) experimental pneumonia (i/p LPS injection, 1mg/kg); and 4) experimental pneumonia treated with CeO2 NP (4 times during the study in dosage of 0.6mg/kg with an orogastric catheter). Gas exchange and pulmonary ventilation were measured four times: 0, 1, 3 and 24h after LPS injection in both untreated and CeO2 NP-treated animals. The mRNA of TNF-α, Il-6, and CxCL2 were determined by RT-PCR. ROS-generation in blood plasma and lung tissue homogenates were measured by means of lucigenin- and luminol-enhanced chemiluminescence. Endotoxemia in the acute phase was associated with: (1) pathological changes in lung morphology; (2) increase of ROS generation; (3) enhanced expression of CxCL2; and (4) a gradual decrease of VO2 and VE. CeO2 NP treatment of intact animals did not make any changes in all studied parameters except for a significant augmentation of VO2 and VE. CeO2 NP treatment of rats with pneumonia created positive changes in diminishing lung tissue injury, decreasing ROS generation in blood and lung tissue and decreasing pro-inflammatory cytokine expression (TNF-α, Il-6 and CxCL2). Oxygen consumption in this group was increased compared to the LPS pneumonia group. In our study we have shown anti-inflammatory and antioxidant effects of CeO2 NP. In addition, this paper is the first to report that CeO2 NP stimulates oxygen consumption in both healthy rats, and rats with pneumonia. We propose the key in understanding the mechanisms behind the phenomena lies in the property of CeO2 NP to scavenge ROS and the influence of this potent antioxidant on mitochondrial function. The study of biodistribution and elimination of СеО2NP is the purpose of our ongoing study.
Collapse
Affiliation(s)
- Z Serebrovska
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine.
| | - R J Swanson
- Liberty University College of Osteopathic Medicine in Lynchburg, 306 Liberty View Lane, Lynchburg, VA24502, USA
| | - V Portnichenko
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine
| | - A Shysh
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine
| | - S Pavlovich
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine
| | - L Tumanovska
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine
| | - A Dorovskych
- Integrative Medicine Clinic "SmartMed", 16 Luteranska St., Kyiv, 01024, Ukraine
| | - V Lysenko
- Lashkariov Institute of Semiconductor Physics, National Academy of Sciences, 41 Nauki Ave., 03028, Kyiv, Ukraine
| | - V Tertykh
- Chuiko Institute of Surface Chemistry, National Academy of Sciences, 17 Generala Naumova St., 03164, Kyiv, Ukraine
| | - Y Bolbukh
- Chuiko Institute of Surface Chemistry, National Academy of Sciences, 17 Generala Naumova St., 03164, Kyiv, Ukraine
| | - V Dosenko
- Bogomoletz Institute of Physiology, National Academy of Sciences, 4 Bogomoletz St., Kyiv 01024, Ukraine
| |
Collapse
|
4
|
Shirole RL, Shirole NL, Saraf MN. Embelia ribes ameliorates lipopolysaccharide-induced acute respiratory distress syndrome. JOURNAL OF ETHNOPHARMACOLOGY 2015; 168:356-63. [PMID: 25818695 DOI: 10.1016/j.jep.2015.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 02/17/2015] [Accepted: 03/04/2015] [Indexed: 05/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Embelia ribes Burm. f. (Fam. Myrsinaceae) locally known as Vidanga have been used for treating tumors, ascites, bronchitis, jaundice, diseases of the heart and brain in traditional Indian medicine. However, no scientific studies providing new insights in its pharmacological properties with respect to acute respiratory distress syndrome have been investigated. AIM The present investigation aimed to elucidate the effectiveness of Embelin isolated from Embelia ribes seeds on attenuation of LPS-induced acute respiratory distress syndrome in murine models. METHODS Embelin (5, 10 and 20 mg/kg/day, i.p.) and Roflumilast (1 mg/kg/day, p.o.) were administered for four days and prior to LPS in rats (i.t.). Four hour after LPS challenge animals were anesthesized and bronchoalveolar lavage was done with ice-cold phosphate buffer. Assessment of BAL fluid was done for albumin, total protein, total cell and neutrophil count, TNF-α levels, nitrosoative stress. Superior lobe of right lung was used for histopathologic evaluation. Inferior lobe of right lung was used to obtain lung edema. Left lung was used for myeloperoxidase estimation. Arterial blood was collected immediately and analyzed for pH, pO2 and pCO2 were estimated. RESULTS Pretreatment with embelin (5, 10 and 20 mg/kg, i.p.) decreased lung edema, mononucleated cellular infiltration, nitrate/nitrite, total protein, albumin concentrations, TNF-α in the bronchoalveolar lavage fluid and myeloperoxidase activity in lung homogenate. Embelin markedly prevented pO2 down-regulation and pCO2 augmentation. Additionally, it attenuated lung histopathological changes in acute respiratory distress syndrome model. CONCLUSION The study demonstrates the effectiveness of Embelia ribes Burm. f. (Fam. Myrsinaceae) seeds in acute respiratory distress syndrome possibly related to its anti-inflammatory and protective effect against LPS induced airway inflammation by reducing nitrosative stress, reducing physiological parameters of blood gas change, TNF-α and mononucleated cellular infiltration indicating it as a potential therapeutic agent for acute respiratory distress syndrome.
Collapse
Affiliation(s)
- R L Shirole
- Department of Pharmacology, A. R. A. College of Pharmacy, Dhule, Maharashtra, India.
| | - N L Shirole
- Department of Pharmaceutical Chemistry, A. R. A. College of Pharmacy, Dhule, Maharashtra, India
| | - M N Saraf
- Department of Pharmacology, Bombay College of Pharmacy, Kalina, Santacruz (E), Mumbai, Maharashtra, India
| |
Collapse
|
5
|
Sun Y, Li H, Yang MF, Shu W, Sun MJ, Xu Y. Effects of aging on endotoxin tolerance induced by lipopolysaccharides derived from Porphyromonas gingivalis and Escherichia coli. PLoS One 2012; 7:e39224. [PMID: 22723968 PMCID: PMC3377652 DOI: 10.1371/journal.pone.0039224] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 05/17/2012] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Periodontitis is a bacterially induced chronic inflammatory disease. Exposure of the host to periodontal pathogens and their virulence factors induces a state of hyporesponsiveness to subsequent stimulations, termed endotoxin tolerance. Aging has a profound effect on immune response to bacteria challenge. The aim of this study was to explore the effects of aging on endotoxin tolerance induced by Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) and Escherichia coli (E. coli) LPS in murine peritoneal macrophages. METHODOLOGY/PRINCIPAL FINDINGS We studied the cytokine production (TNF-α and IL-10) and Toll-like receptor 2, 4 (TLR2, 4) gene and protein expressions in peritoneal macrophages from young (2-month-old) and middle-aged (12-month-old) ICR mice following single or repeated P. gingivalis LPS or E. coli LPS stimulation. Pretreatment of peritoneal macrophages with P. gingivalis LPS or E. coli LPS resulted in a reduction in TNF-α production and an increase in IL-10 production upon secondary stimulation (p<0.05), and the markedly lower levels of TNF-α and higher levels of IL-10 were observed in macrophages from young mice compared with those from middle-aged mice (p<0.05). In addition, LPS restimulations also led to the significantly lower expression levels of TLR2, 4 mRNA and protein in macrophages from young mice (p<0.05). CONCLUSIONS/SIGNIFICANCE Repeated LPS stimulations triggered endotoxin tolerance in peritoneal macrophages and the ability to develop tolerance in young mice was more excellent. The impaired ability to develop endotoxin tolerance resulted from aging might be related to TLR2, 4 and might lead to the incontrollable periodontal inflammation in older adults.
Collapse
Affiliation(s)
- Ying Sun
- Institute of Stomatology, Nanjing Medical University, Nanjing, China
- Department of Periodontology, Stomatology Hospital affiliated to Nanjing Medical University, Nanjing, China
| | - Hui Li
- Institute of Stomatology, Nanjing Medical University, Nanjing, China
- Department of Periodontology, Stomatology Hospital affiliated to Nanjing Medical University, Nanjing, China
| | - Mi-Fang Yang
- Institute of Stomatology, Nanjing Medical University, Nanjing, China
| | - Wei Shu
- Department of Periodontology, Stomatology Hospital affiliated to Nanjing Medical University, Nanjing, China
| | - Meng-Jun Sun
- Institute of Stomatology, Nanjing Medical University, Nanjing, China
- Department of Periodontology, Stomatology Hospital affiliated to Nanjing Medical University, Nanjing, China
| | - Yan Xu
- Institute of Stomatology, Nanjing Medical University, Nanjing, China
- Department of Periodontology, Stomatology Hospital affiliated to Nanjing Medical University, Nanjing, China
| |
Collapse
|
6
|
Chavez SA, Martinko AJ, Lau C, Pham MN, Cheng K, Bevan DE, Mollnes TE, Yin H. Development of β-amino alcohol derivatives that inhibit Toll-like receptor 4 mediated inflammatory response as potential antiseptics. J Med Chem 2011; 54:4659-69. [PMID: 21591694 PMCID: PMC3131463 DOI: 10.1021/jm2003365] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Toll-like receptor 4 (TLR4) induced proinflammatory signaling has been directly implicated in severe sepsis and represents an attractive therapeutic target. Herein, we report our investigations into the structure-activity relationship and preliminary drug metabolism/pharmacokinetics study of β-amino alcohol derivatives that inhibit the TLR4 signaling pathway. Lead compounds were identified from in vitro cellular examination with micromolar potency for their inhibitory effects on TLR4 signaling and subsequently assessed for their ability to suppress the TLR4-induced inflammatory response in an ex vivo whole blood model. In addition, the toxicology, specificity, solubility, brain-blood barrier permeability, and drug metabolism of several compounds were evaluated. Although further optimizations are needed, our findings lay the groundwork for the future drug development of this class of small molecule agents for the treatment of severe sepsis.
Collapse
Affiliation(s)
- Sherry A. Chavez
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Alexander J. Martinko
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Corinna Lau
- Research Laboratory, Nordland Hospital, Bodø, Norway NO-8092
| | - Michael N. Pham
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Kui Cheng
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Douglas E. Bevan
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| | - Tom E. Mollnes
- Research Laboratory, Nordland Hospital, Bodø, Norway NO-8092
- University of Tromsø, Tromsø, Norway NO-9037
| | - Hang Yin
- Department of Chemistry and Biochemistry University of Colorado at Boulder, Boulder, CO 80309, USA
| |
Collapse
|
7
|
Shi DW, Zhang J, Jiang HN, Tong CY, Gu GR, Ji Y, Summah H, Qu JM. LPS pretreatment ameliorates multiple organ injuries and improves survival in a murine model of polymicrobial sepsis. Inflamm Res 2011; 60:841-9. [PMID: 21556916 DOI: 10.1007/s00011-011-0342-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 03/29/2011] [Accepted: 04/17/2011] [Indexed: 12/01/2022] Open
Abstract
OBJECTIVE The endotoxin tolerance phenotype is characterized with decreased inflammation and increased phagocytosis. We hypothesized that endotoxin tolerance would provide protective effects on experimental sepsis with multiple organ injuries induced by cecal ligation and puncture (CLP). METHODS Endotoxin tolerance was induced in male Sprague-Dawley rats with daily intraperitoneal injection of either 0.6 mg/kg of lipopolysaccharide (LPS) or vehicle for four consecutive days before subsequent CLP. Biochemical parameters, histological changes, inflammatory cytokine production, and lung tissue nuclear factor-κB (NF-κB) activation were assessed post-CLP. In a separate experiment, survival rate was monitored for 7 days after CLP. RESULTS In vehicle-treated animals, CLP caused multiple organ injuries confirmed by the biochemical variables and histological examination. This was accompanied by an early activation of NF-κB in the lung and a substantial increase in plasma levels of tumor necrosis factor-α, interleukin-6, and interleukin-10. In contrast, pretreatment with LPS not only alleviated the development of multiple organ injuries after CLP, but also decreased sepsis-induced activation of pulmonary NF-κB and reduced plasma cytokines production. In addition, LPS pretreatment improved the survival in rats subjected to CLP. CONCLUSIONS The beneficial effects of endotoxin tolerance indicate the potential of immunomodulatory strategies in the management of severe sepsis.
Collapse
Affiliation(s)
- Dong-Wei Shi
- Department of Emergency Medicine, Zhongshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Up-regulation of growth factor independence 1 in endotoxin tolerant macrophages with low secretion of TNF-alpha and IL-6. Inflamm Res 2010; 59:855-60. [PMID: 20401626 DOI: 10.1007/s00011-010-0197-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2010] [Revised: 02/19/2010] [Accepted: 03/25/2010] [Indexed: 10/19/2022] Open
Abstract
OBJECTIVE Endotoxin tolerance refers to a low response to lipopolysaccharide (LPS). We hypothesized that growth factor independence 1 (Gfi1) involves in the endotoxin tolerance in macrophages. METHODS Endotoxin tolerance was induced in the RAW264.7 cell line and thioglycolate-elicited murine peritoneal macrophages by incubation with 100 ng/ml LPS for 20 h. Macrophages without the pretreatment were set as control. Both endotoxin tolerant and control cells were then stimulated with 1,000 ng/ml LPS for indicated period of incubation. Gfi1 mRNA expression and protein production were investigated by real-time PCR and Western blotting, respectively. ELISA was performed to quantify the secretion of TNF-alpha and IL-6. RESULT Compared with non-endotoxin tolerant macrophages, endotoxin tolerant cells secreted a lower amount of TNF-alpha and IL-6. The mRNA expression of Gfi1 in endotoxin tolerant macrophages was higher than that of control in both RAW264.7 cells and thioglycolate-elicited murine peritoneal macrophages. The protein production was accordingly up-regulated in endotoxin tolerant RAW264.7 cells. CONCLUSION In in vitro endotoxin tolerant macrophages, the expression of Gfi1 mRNA and protein were up-regulated after high dose LPS stimulation, accompanied with a blunted TNF-alpha and IL-6 secretion. Gfi1 might participate in the mechanism of endotoxin tolerance.
Collapse
|
9
|
Zhang J, Qu JM, He LX. IL-12 suppression, enhanced endocytosis and up-regulation of MHC-II and CD80 in dendritic cells during experimental endotoxin tolerance. Acta Pharmacol Sin 2009; 30:582-8. [PMID: 19349963 DOI: 10.1038/aps.2009.34] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
AIM The aim of this study was to investigate endocytosis, MHC-II expression and co-stimulatory molecule expression, as well as interleukin-12 (IL-12) production, in bone marrow dendritic cells (DCs) derived from endotoxin tolerant mice. METHODS Endotoxin tolerance was induced in C57BL/10J mice through four consecutive daily intraperitoneal injections of 1.0 mg/kg of 055:B5 Escherichia coli lipopolysaccharide (LPS). Bone marrow DCs were isolated in the presence of GM-CSF and IL-4 and purified by anti-CD11c Micro beads. FITC-dextran uptake by DCs was tested by flow cytometric analysis and the percentage of dextran-containing cells was calculated using a fluorescence microscope. The expression of surface MHC-II, CD40, CD80, and CD86 was also detected by flow cytometric analysis. An ELISA was used for the measurement of IL-12 production by DCs with or without LPS stimulation. RESULTS Endotoxin tolerance was successfully induced in C57BL/10J mice, evidenced by an attenuated elevation of systemic TNF-alpha. DCs from endotoxin tolerant mice possessed enhanced dextran endocytosis ability. The expression of surface MHC-II and CD80 was higher in DCs from endotoxin tolerant mice than in DCs from control mice, whereas the expression of CD40 and CD86 was not altered. Compared with DCs from normal control mice, DCs from endotoxin tolerant mice produced less IL-12 after subsequent in vitro stimulation with LPS. CONCLUSION These data suggest enhanced endocytosis, selective up-regulation of MHC-II and CD80 and IL-12 suppression in DCs during in vivo induction of endotoxin tolerance.
Collapse
|
10
|
Cell Defence and Survival. GUIDE TO SIGNAL PATHWAYS IN IMMUNE CELLS 2009. [PMCID: PMC7123614 DOI: 10.1007/978-1-60327-538-5_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Central to immune defence mechanisms is the role of transcription factor nuclear factor kappa B (NF-kB). This is a complex biochemical topic with ever more controls revealed. NF-kB determines the production of proinflammatory cytokines and chemokines. Pharmacologists step in with possible means of control. Other systems involved in defence include the cyclooxygenase 2 (Cox-2) enzyme and perioxisome proliferator-activated receptors. Insulin receptor activation needs to be seen in context. The mTOR system directs uptake of nutrients by cells. mTOR is suppressed by rapamycin, whose usage is now quite considerable in the control of transplant rejection.
Collapse
|
11
|
Discovery and development of toll-like receptor 4 (TLR4) antagonists: a new paradigm for treating sepsis and other diseases. Pharm Res 2008; 25:1751-61. [PMID: 18493843 PMCID: PMC2469272 DOI: 10.1007/s11095-008-9571-x] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Accepted: 03/13/2008] [Indexed: 02/06/2023]
Abstract
Sepsis remains the most common cause of death in intensive care units in the USA, with a current estimate of at least 750,000 cases per year, and 215,000 deaths annually. Despite extensive research still we do not quite understand the cellular and molecular mechanisms that are involved in triggering and propagation of septic injury. Endotoxin (lipopolysaccharide from Gram-negative bacteria, or LPS) has been implicated as a major cause of this syndrome. Inflammatory shock as a consequence of LPS release remains a serious clinical concern. In humans, inflammatory responses to LPS result in the release of cytokines and other cell mediators from monocytes and macrophages, which can cause fever, shock, organ failure and death. A number of different approaches have been investigated to try to treat and/or prevent the septic shock associated with infections caused by Gram-negative bacteria, including blockage of one or more of the cytokines induced by LPS. Recently several novel amphipathic compounds have been developed as direct LPS antagonists at the LPS receptor, TLR4. This review article will outline the current knowledge on the TLR4-LPS synthesis and discuss the signaling, in vitro pre-clinical and in vivo clinical evaluation of TLR4 antagonists and their potential use in sepsis and a variety of diseases such as atherosclerosis as well as hepatic and renal malfunction.
Collapse
|
12
|
De Boever S, Beyaert R, Vandemaele F, Baert K, Duchateau L, Goddeeris B, De Backer P, Croubels S. The influence of age and repeated lipopolysaccharide administration on body temperature and the concentration of interleukin-6 and IgM antibodies against lipopolysaccharide in broiler chickens. Avian Pathol 2008; 37:39-44. [DOI: 10.1080/03079450701784875] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- S. De Boever
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - R. Beyaert
- b Department for Molecular Biomedical Research, VIB , Unit of Molecular Signal Transduction in Inflammation , Ghent , Belgium
- c Department of Molecular Biology , Ghent University , Ghent , Belgium
| | - F. Vandemaele
- d Department Biosystems, Laboratory of Livestock Physiology, Immunology and Genetics, Faculty of Bioscience Engineering, K.U. Leuven , Leuven , Belgium
| | - K. Baert
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - L. Duchateau
- e Department of Physiology and Biometrics, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - B. Goddeeris
- d Department Biosystems, Laboratory of Livestock Physiology, Immunology and Genetics, Faculty of Bioscience Engineering, K.U. Leuven , Leuven , Belgium
| | - P. De Backer
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| | - S. Croubels
- a Department of Pharmacology, Toxicology, Biochemistry and Organ Physiology, Faculty of Veterinary Medicine , Ghent University , Merelbeke , Belgium
| |
Collapse
|
13
|
Koch A, Boehm O, Zacharowski PA, Loer SA, Weimann J, Rensing H, Foster SJ, Schmidt R, Berkels R, Reingruber S, Zacharowski K. Inducible nitric oxide synthase and heme oxygenase-1 in the lung during lipopolysaccharide tolerance and cross tolerance. Crit Care Med 2007; 35:2775-84. [PMID: 17901834 DOI: 10.1097/01.ccm.0000288122.24212.40] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
OBJECTIVE Pretreatment with low-dose lipopolysaccharide protects cells/organs against a subsequent lethal Gram-negative (lipopolysaccharide tolerance) or Gram-positive (cross tolerance) stimulus. We determined whether this occurs in the rat lung. The involvement of inducible nitric oxide synthase and heme oxygenase-1 was evaluated. DESIGN Laboratory study. SETTING University hospital laboratory. SUBJECTS Anesthetized male Wistar rats. INTERVENTIONS To test the hypothesis, rats received saline or lipopolysaccharide (1 mg/kg). At 2, 4, 8, 16, or 24 hrs later, blood samples and lung tissue were taken to determine messenger RNA, protein concentration, and activity of inducible nitric oxide synthase and heme oxygenase-1. In additional experiments, rats were challenged with lipopolysaccharide (1 mg/kg) and subjected to Gram-negative (lipopolysaccharide) or Gram-positive (lipoteichoic acid and peptidoglycan) shock 24 hrs later. These studies were carried out in the presence and absence of inducible nitric oxide synthase or heme oxygenase-1 inhibitors (1400W or tin protoporphyrin IX). Following 6 hrs of shock, lung tissue was taken to determine lung damage and heme oxygenase-1 concentration and activity. MEASUREMENTS AND MAIN RESULTS In the rat lung, lipopolysaccharide (1 mg/kg) induced a significant increase in inducible nitric oxide synthase protein at 8 hrs with a corresponding increase in plasma nitrate/nitrite at 8-16 hrs. Simultaneously, heme oxygenase-1 messenger RNA transcripts were observed at 8-16 hrs, and maximal expression of the protein followed (24 hrs). Pretreatment with low-dose lipopolysaccharide reduced myeloperoxidase activity (neutrophil infiltration) and wet-dry ratio (pulmonary edema) in the lungs of animals subjected to Gram-negative or Gram-positive shock, demonstrating tolerance. Pretreatment with low-dose lipopolysaccharide and the selective inducible nitric oxide synthase inhibitor 1400W reduced heme oxygenase-1 protein expression, and lung protection was abolished. Tin protoporphyrin IX did not affect heme oxygenase-1 expression, but heme oxygenase activity and lung protection were significantly reduced. CONCLUSIONS We propose that nitric oxide (most likely inducible nitric oxide synthase derived) regulates the induction of heme oxygenase-1 in the lung, which in turn plays an important part in pulmonary protection during lipopolysaccharide tolerance and cross tolerance.
Collapse
Affiliation(s)
- Alexander Koch
- Molecular Cardioprotection and Inflammation Group, Department of Anesthesia, Bristol University, Bristol, UK
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Inducible nitric oxide synthase and heme oxygenase-1 in the lung during lipopolysaccharide tolerance and cross tolerance. Crit Care Med 2007. [DOI: 10.1097/00003246-200712000-00016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
|
15
|
HMGB1 and LPS induce distinct patterns of gene expression and activation in neutrophils from patients with sepsis-induced acute lung injury. Intensive Care Med 2007. [PMID: 17581740 DOI: 10.1007/s00134-] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
OBJECTIVES Circulating levels of the proinflammatory mediator High Mobility Group Box Protein 1 (HMGB1) are increased in septic patients and may contribute to sepsis-induced organ dysfunction. Although HMGB1 has been shown to activate neutrophils from healthy volunteers, the responses of neutrophils from septic patients to HMGB1 have not been reported. In the present study we evaluated gene expression and activation of major intracellular signaling pathways in peripheral blood neutrophils obtained from patients with sepsis-induced acute lung injury after culture with HMGB1 or LPS. DESIGN Ex-vivo study performed in neutrophils from patients with sepsis-induced acute lung injury. SETTING Immunology and genetics laboratory at an academic medical center. PATIENTS AND PARTICIPANTS Twenty-two adult patients with sepsis-induced acute lung injury. MEASUREMENTS AND RESULTS Using gene arrays, distinct patterns of gene expression were found in neutrophils from septic patients after stimulation with HMGB1 or LPS. While more than three-quarters of the genes upregulated by HMGB1 in neutrophils from septic patients also demonstrated increased expression after culture with LPS, the majority of genes affected by LPS did not show altered expression in neutrophils stimulated with HMGB1. Culture of neutrophils with HMGB1 induced downregulation of its own expression, a finding not present after exposure to LPS. Although HMGB1 and LPS both increased nuclear translocation of NF-kappaB, the magnitude of this effect was greater in LPS stimulated neutrophils from patients with sepsis-induced acute lung injury. CONCLUSION These findings demonstrate that the patterns of gene expression differ between neutrophils from septic patients stimulated with HMGB1 or LPS, and also that neutrophils from septic patients are not anergic but instead demonstrate intact activation of NF-kappaB after exposure to LPS or HMGB1.
Collapse
|
16
|
Silva E, Arcaroli J, He Q, Svetkauskaite D, Coldren C, Nick JA, Poch K, Park JS, Banerjee A, Abraham E. HMGB1 and LPS induce distinct patterns of gene expression and activation in neutrophils from patients with sepsis-induced acute lung injury. Intensive Care Med 2007; 33:1829-39. [PMID: 17581740 DOI: 10.1007/s00134-007-0748-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2006] [Accepted: 05/21/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVES Circulating levels of the proinflammatory mediator High Mobility Group Box Protein 1 (HMGB1) are increased in septic patients and may contribute to sepsis-induced organ dysfunction. Although HMGB1 has been shown to activate neutrophils from healthy volunteers, the responses of neutrophils from septic patients to HMGB1 have not been reported. In the present study we evaluated gene expression and activation of major intracellular signaling pathways in peripheral blood neutrophils obtained from patients with sepsis-induced acute lung injury after culture with HMGB1 or LPS. DESIGN Ex-vivo study performed in neutrophils from patients with sepsis-induced acute lung injury. SETTING Immunology and genetics laboratory at an academic medical center. PATIENTS AND PARTICIPANTS Twenty-two adult patients with sepsis-induced acute lung injury. MEASUREMENTS AND RESULTS Using gene arrays, distinct patterns of gene expression were found in neutrophils from septic patients after stimulation with HMGB1 or LPS. While more than three-quarters of the genes upregulated by HMGB1 in neutrophils from septic patients also demonstrated increased expression after culture with LPS, the majority of genes affected by LPS did not show altered expression in neutrophils stimulated with HMGB1. Culture of neutrophils with HMGB1 induced downregulation of its own expression, a finding not present after exposure to LPS. Although HMGB1 and LPS both increased nuclear translocation of NF-kappaB, the magnitude of this effect was greater in LPS stimulated neutrophils from patients with sepsis-induced acute lung injury. CONCLUSION These findings demonstrate that the patterns of gene expression differ between neutrophils from septic patients stimulated with HMGB1 or LPS, and also that neutrophils from septic patients are not anergic but instead demonstrate intact activation of NF-kappaB after exposure to LPS or HMGB1.
Collapse
Affiliation(s)
- Eliezer Silva
- Intensive Care Unit, Hospital Israelita Albert Einstein, Sao Paulo, SP, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Yeh CC, Lin CC, Wang SD, Chen YS, Su BH, Kao ST. Protective and anti-inflammatory effect of a traditional Chinese medicine, Xia-Bai-San, by modulating lung local cytokine in a murine model of acute lung injury. Int Immunopharmacol 2006; 6:1506-14. [PMID: 16846845 DOI: 10.1016/j.intimp.2006.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Revised: 01/26/2006] [Accepted: 04/12/2006] [Indexed: 01/15/2023]
Abstract
We investigated the effects of Xia-Bai-San (XBS) on acute lung inflammation induced by LPS in vivo. Mice were challenged with intratracheal lipopolysaccharide (100 microg) 30 min before administering XBS (1 mg/kg oral administration). Bronchoalveolar lavage fluid (BALF) was obtained after 4 and 24 h to measure proinflammatory cytokine (TNF-alpha, IL-1beta, IL-6), anti-inflammatory cytokines (IL-10), chemokines (KC, MCP-1 and MIP-2), total cell counts, nitric oxide production, and proteins. The results indicated that XBS down-regulated the LPS-induced expression of TNF-alpha, IL-1beta, IL-6, KC, MIP-2, and MCP-1. Furthermore, it also enhanced the production of IL-10, which had increased 24 h after LPS challenge. In addition, total leukocyte counts, nitric oxide production, iNOS expression, and BALF's proteins had significantly decreased 24 h after LPS challenge. XBS was also believes to have reduced the acute inflammation by attenuating the activation of NF-kappaB. In conclusion, XBS seem to suppress lipopolysaccharide-induced lung inflammation by stimulating the production of anti-inflammatory cytokines in lung. These results suggest that XBS could be a useful adjunct in the treatment of acute respiratory distress syndrome.
Collapse
Affiliation(s)
- Chia-Chou Yeh
- Institute of Chinese Medical Science, College of Chinese Medicine, China Medical University, Taichung, Taiwan
| | | | | | | | | | | |
Collapse
|
18
|
Baumgarten G, Knuefermann P, Wrigge H, Putensen C, Stapel H, Fink K, Meyer R, Hoeft A, Grohé C. Role of Toll-like receptor 4 for the pathogenesis of acute lung injury in Gram-negative sepsis. Eur J Anaesthesiol 2006; 23:1041-8. [PMID: 16836770 DOI: 10.1017/s0265021506001098] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2006] [Indexed: 11/06/2022]
Abstract
BACKGROUND AND OBJECTIVE Proinflammatory cytokines as well as nitric oxide (NO) play a major role in mediating the response to lipopolysaccharide (LPS). The present study tested the hypothesis that LPS induces proinflammatory cytokines in the lung via the Toll-like receptor 4 (TLR4)/CD14 signalling cascade. METHODS Control mice and TLR4-deficient (TLR4-D) mice were used to test TLR4-mediated effects of LPS. Both strains received either Escherichia coli LPS (20 mg kg-1 intraperitoneal) or saline and their lungs were collected at different time points. Pulmonary nuclear factor kappaB (NFkappaB) activation was investigated with electromobility shift assay. mRNA expression of inflammatory mediators and their corresponding receptors were detected with Ribonuclease Protection Assay. Protein expression was detected by ELISA and western blotting. Inducible NO synthase (iNOS) expression was monitored by RT-PCR and iNOS activity by conversion of l-arginine to citrulline. Immune cells were sampled by bronchoalveolar lavage (BAL) and classified. RESULTS LPS application induced CD14-, but not TLR4 protein expression in control mice. Activation of pulmonary NFkappaB was observed within 60 min in control, but not in TLR4-D mice. Six hours of LPS administration induced a significant increase in pulmonary tumour necrosis factor alpha-, interleukin-1beta- and interleukin-6 mRNA and protein expression in control mice compared to TLR4-D mice. Furthermore, LPS induced a significantly higher increase of the iNOS expression and catalytic activity in control mice than in TLR4-D mice. BAL revealed an increase in total cell count in all LPS treated mice. CONCLUSION Our findings suggest that TLR4 plays a key role for regulating the expression of relevant cytokines within the lung during endotoxic shock.
Collapse
Affiliation(s)
- G Baumgarten
- Universitätsklinikum Bonn, Department of Anesthesiology and Intensive Care Medicine, Bonn, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Tsujimoto H, Ono S, Majima T, Efron PA, Kinoshita M, Hiraide H, Moldawer LL, Mochizuki H. Differential toll-like receptor expression after ex vivo lipopolysaccharide exposure in patients with sepsis and following surgical stress. Clin Immunol 2006; 119:180-7. [PMID: 16517212 DOI: 10.1016/j.clim.2006.01.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2005] [Revised: 12/15/2005] [Accepted: 01/17/2006] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Monocytes from septic patients have a reduced capacity to respond to lipopolysaccharide (LPS). We examined whether the same response occurred after surgical injury, and whether this reduced activity was associated with differential monocyte toll-like receptor (TLR) expression. MATERIALS AND METHODS Peripheral blood mononuclear cells (PBMCs) were isolated from septic patients, patients undergoing surgery, and healthy volunteers. Cells were stimulated ex vivo with LPS (1 microg/ml) and stained for CD14, CD16, TLR-2, TLR-4, and HLA-DR surface expression. RESULTS TLR-2 and -4 expressions were significantly increased in monocytes from both septic and surgical patients. While ex vivo LPS-stimulation significantly increased TNFalpha and IL-1beta production in PBMCs from surgical patients, LPS-stimulation decreased IL-1beta production from septic patients as compared to surgical and control patients. Ex vivo LPS-stimulation induced TLR-4 upregulation in monocytes from both surgical and control patients, but not from septic patients. HLA-DR expression in CD14+CD16+ monocytes was reduced only in septic patients. CONCLUSIONS PBMCs from septic patients, but not following surgical injury, have a reduced capacity to respond to a secondary inflammatory signal, but this defect is not associated with reduced TLR-4 or CD14 expression.
Collapse
Affiliation(s)
- Hironori Tsujimoto
- Department of Surgery I, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Steinmüller M, Srivastava M, Kuziel WA, Christman JW, Seeger W, Welte T, Lohmeyer J, Maus UA. Endotoxin induced peritonitis elicits monocyte immigration into the lung: implications on alveolar space inflammatory responsiveness. Respir Res 2006; 7:30. [PMID: 16503998 PMCID: PMC1388208 DOI: 10.1186/1465-9921-7-30] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Accepted: 02/18/2006] [Indexed: 11/20/2022] Open
Abstract
Background Acute peritonitis developing in response to gram-negative bacterial infection is known to act as a trigger for the development of acute lung injury which is often complicated by the development of nosocomial pneumonia. We hypothesized that endotoxin-induced peritonitis provokes recruitment of monocytes into the lungs, which amplifies lung inflammatory responses to a second hit intra-alveolar challenge with endotoxin. Methods Serum and lavage cytokines as well as bronchoalveolar lavage fluid cells were analyzed at different time points after intraperitoneal or intratracheal application of LPS. Results We observed that mice challenged with intraperitoneal endotoxin developed rapidly increasing serum and bronchoalveolar lavage fluid (BALF) cytokine and chemokine levels (TNFα, MIP-2, CCL2) and a nearly two-fold expansion of the alveolar macrophage population by 96 h, but this was not associated with the development of neutrophilic alveolitis. In contrast, expansion of the alveolar macrophage pool was not observed in CCR2-deficient mice and in wild-type mice systemically pretreated with the anti-CD18 antibody GAME-46. An intentional two-fold expansion of alveolar macrophage numbers by intratracheal CCL2 following intraperitoneal endotoxin did not exacerbate the development of acute lung inflammation in response to intratracheal endotoxin compared to mice challenged only with intratracheal endotoxin. Conclusion These data, taken together, show that intraperitoneal endotoxin triggers a CCR2-dependent de novo recruitment of monocytes into the lungs of mice but this does not result in an accentuation of neutrophilic lung inflammation. This finding represents a previously unrecognized novel inflammatory component of lung inflammation that results from endotoxin-induced peritonitis.
Collapse
Affiliation(s)
- Mirko Steinmüller
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Infectious Diseases, Justus-Liebig-University, Giessen, Germany
| | - Mrigank Srivastava
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Infectious Diseases, Justus-Liebig-University, Giessen, Germany
- Department of Pulmonary Medicine, Laboratory for Experimental Lung Research, Hannover School of Medicine, Hannover, Germany
| | | | | | - Werner Seeger
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Infectious Diseases, Justus-Liebig-University, Giessen, Germany
| | - Tobias Welte
- Department of Pulmonary Medicine, Laboratory for Experimental Lung Research, Hannover School of Medicine, Hannover, Germany
| | - Jürgen Lohmeyer
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Infectious Diseases, Justus-Liebig-University, Giessen, Germany
| | - Ulrich A Maus
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine and Infectious Diseases, Justus-Liebig-University, Giessen, Germany
- Department of Pulmonary Medicine, Laboratory for Experimental Lung Research, Hannover School of Medicine, Hannover, Germany
| |
Collapse
|
21
|
Lim CM, Kim EK, Koh Y, Kim WS, Kim DS, Kim WD. Hypothermia inhibits cytokine release of alveolar macrophage and activation of nuclear factor kappaB in endotoxemic lung. Intensive Care Med 2004; 30:1638-44. [PMID: 15168012 DOI: 10.1007/s00134-004-2336-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2003] [Accepted: 05/10/2004] [Indexed: 12/30/2022]
Abstract
OBJECTIVE We have previously reported that endotoxin-induced neutrophil infiltration of the lung is lower during hypothermia than during normothermia. Because neutrophil infiltration of the lung is considered a downstream phenomenon following an activation of tissue macrophages, we examined the effects of induced hypothermia on the proximal aspects of acute lung injury, which involves alveolar macrophages and nuclear transcription of cytokine genes. DESIGN AND SETTING Animal study in an institutional animal laboratory. SUBJECTS Thirty-six Sprague-Dawley rats. INTERVENTIONS Rats were assigned to the following groups: normothermia (37 degrees C) with saline; hypothermia (27 degrees C) with saline; normothermia with lipopolysaccharide; hypothermia with lipopolysaccharide. After 1 h of stable temperature rats were intraperitoneally given lipopolysaccharide or an equivalent volume of normal saline. The temperature of rats was maintained within +/-1 degrees C of the target temperature for the subsequent 2 h, after which rats were subjected to lung lavage. MEASUREMENTS AND RESULTS Neutrophil count, TNF-alpha, and IL-1beta in lavage fluid were all higher with normothermia-LPS than in normothermia-saline. Neutrophil count, TNF-alpha, and IL-1beta levels of lavage fluid were lower with hypothermia-LPS than with normothermia-LPS. TNF-alpha release from cultured alveolar macrophages and NF-kappaB activity in lung tissue were both lower with hypothermia-LPS than with normothermia-LPS. I-kappaBalpha level in lung tissue was lower with normothermia-LPS than with the normothermia-saline, whereas I-kappaBalpha level in lung tissue did not differ between normothermia-saline and hypothermia-LPS. CONCLUSIONS Induced hypothermia suppressed the release of inflammatory cytokine from alveolar macrophages and NF-kappaB activation in endotoxemic lung.
Collapse
|