1
|
Arunachalam AR, Samuel SS, Mani A, Maynard JP, Stayer KM, Dybbro E, Narayanan S, Biswas A, Pathan S, Soni K, Kamal AHM, Ambati CSR, Putluri N, Desai MS, Thevananther S. P2Y2 purinergic receptor gene deletion protects mice from bacterial endotoxin and sepsis-associated liver injury and mortality. Am J Physiol Gastrointest Liver Physiol 2023; 325:G471-G491. [PMID: 37697947 PMCID: PMC10812707 DOI: 10.1152/ajpgi.00090.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/28/2023] [Accepted: 09/11/2023] [Indexed: 09/13/2023]
Abstract
The liver plays a significant role in regulating a wide range of metabolic, homeostatic, and host-defense functions. However, the impact of liver injury on the host's ability to control bacteremia and morbidity in sepsis is not well understood. Leukocyte recruitment and activation lead to cytokine and chemokine release, which, in turn, trigger hepatocellular injury and elevate nucleotide levels in the extracellular milieu. P2Y2 purinergic receptors, G protein-coupled and activated by extracellular ATP/UTP, are expressed at the cell surface of hepatocytes and nonparenchymal cells. We sought to determine whether P2Y2 purinergic receptor function is necessary for the maladaptive host response to bacterial infection and endotoxin-mediated inflammatory liver injury and mortality in mice. We report that P2Y2 purinergic receptor knockout mice (P2Y2-/-) had attenuated inflammation and liver injury, with improved survival in response to LPS/galactosamine (LPS/GalN; inflammatory liver injury) and cecal ligation and puncture (CLP; polymicrobial sepsis). P2Y2-/- livers had attenuated c-Jun NH2-terminal kinase activation, matrix metallopeptidase-9 expression, and hepatocyte apoptosis in response to LPS/GalN and attenuated inducible nitric oxide synthase and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 protein expression in response to CLP. Implicating liver injury in the disruption of amino acid homeostasis, CLP led to lower serum arginine and higher bacterial load and morbidity in the WT mice, whereas serum arginine levels were comparable to sham-operated controls in P2Y2-/- mice, which had attenuated bacteremia and improved survival. Collectively, our studies highlight the pathophysiological relevance of P2Y2 purinergic receptor function in inflammatory liver injury and dysregulation of systemic amino acid homeostasis with implications for sepsis-associated immune dysfunction and morbidity in mice.NEW & NOTEWORTHY Our studies provide experimental evidence for P2Y2 purinergic receptor-mediated potentiation of inflammatory liver injury, morbidity, and mortality, in two well-established animal models of inflammatory liver injury. Our findings highlight the potential to target P2Y2 purinergic signaling to attenuate the induction of "cytokine storm" and prevent its deleterious consequences on liver function, systemic amino acid homeostasis, host response to bacterial infection, and sepsis-associated morbidity and mortality.
Collapse
Affiliation(s)
- Athis R Arunachalam
- Neonatology, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Sanju S Samuel
- Critical Care Medicine, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Arunmani Mani
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Janielle P Maynard
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Kelsey M Stayer
- Critical Care Medicine, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Eric Dybbro
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Subapradha Narayanan
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Aalekhya Biswas
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Saliha Pathan
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Krishnakant Soni
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Abu Hena Mostafa Kamal
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States
| | | | - Nagireddy Putluri
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States
| | - Moreshwar S Desai
- Critical Care Medicine, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| | - Sundararajah Thevananther
- Section of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States
| |
Collapse
|
2
|
Tasnim F, Huang X, Lee CZW, Ginhoux F, Yu H. Recent Advances in Models of Immune-Mediated Drug-Induced Liver Injury. FRONTIERS IN TOXICOLOGY 2022; 3:605392. [PMID: 35295156 PMCID: PMC8915912 DOI: 10.3389/ftox.2021.605392] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 03/30/2021] [Indexed: 12/12/2022] Open
Abstract
Hepatic inflammation is a key feature of a variety of liver diseases including drug-induced liver injury (DILI), orchestrated by the innate immune response (Kupffer cells, monocytes, neutrophils, dendritic cells) and the adaptive immune system (T cells and natural killer T cells). In contrast to acute DILI, prediction of immune-mediated DILI (im-DILI) has been more challenging due to complex disease pathogenesis, lack of reliable models and limited knowledge of underlying mechanisms. This review summarizes in vivo and in vitro systems that have been used to model im-DILI. In particular, the review focuses on state-of-the-art in vitro human-based multicellular models which have been developed to supplement the use of in vivo models due to interspecies variation and increasing ethical concerns regarding animal use. Advantages of the co-cultures in maintaining hepatocyte functions and importantly, introducing heterotypic cell-cell interactions to mimic inflammatory hepatic microenvironment are discussed. Challenges regarding cell source and incorporation of different cells with physical cell-cell contact are outlined and potential solutions are proposed. It is likely that better understanding of the interplay of immune cells in liver models will allow for the development of more accurate systems to better predict hepatotoxicity and stratification of drugs that can cause immune-mediated effects.
Collapse
Affiliation(s)
- Farah Tasnim
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore
| | - Xiaozhong Huang
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christopher Zhe Wei Lee
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Singapore Immunology Network, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Florent Ginhoux
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Singapore Immunology Network, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Shanghai Institute of Immunology, Shanghai JiaoTong University School of Medicine, Shanghai, China.,Translational Immunology Institute, SingHealth Duke-NUS Academic Medical Centre, Singapore, Singapore
| | - Hanry Yu
- Innovations in Food & Chemical Safety Programme, ASTAR, Singapore, Singapore.,Institute of Bioengineering and Nanotechnology, The Nanos, Singapore, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,National University of Singapore (NUS) Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, Singapore, Singapore.,T-Labs, Mechanobiology Institute, Singapore, Singapore.,Critical Analytics for Manufacturing Personalised-Medicine Interdisciplinary Research Groups (CAMP-IRG), Singapore-Massachusetts Institute of Technology Alliance for Research and Technology, Singapore, Singapore
| |
Collapse
|
3
|
Chang CY, Hsu HJ, Foo J, Shih HJ, Huang CJ. Peptide-Based TNF-α-Binding Decoy Therapy Mitigates Lipopolysaccharide-Induced Liver Injury in Mice. Pharmaceuticals (Basel) 2020; 13:ph13100280. [PMID: 33003495 PMCID: PMC7600127 DOI: 10.3390/ph13100280] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/22/2020] [Accepted: 09/28/2020] [Indexed: 12/14/2022] Open
Abstract
A peptide named SEM18, possessing structural similarity to the binding site of tumor necrosis factor (TNF)-α to TNF receptor 1 (TNFR1), was designed. We investigated whether the SEM18 peptide can mitigate lipopolysaccharide (LPS)-induced liver injury in mice. Adult male Balb/cJ mice received LPS (15 mg/kg; LPS group) or LPS plus SEM18 (LSEM group). Control groups were run simultaneously. At 2 h after LPS, the first dose of SEM18 (0.3 mg/kg) was administered, followed by three supplemental doses of SEM18 (0.15 mg/kg, every 2 h). At 24 h after LPS, surviving mice were euthanized for analyses. Compared with the LPS group, binding of TNF-α to TNFR1 in liver tissues was significantly lower in the LSEM group (p < 0.001). Plasma concentrations of aspartate transaminase and alanine transaminase, as well as Suzuki’s scores (liver damage assessment), wet/dry weight ratios, levels of polymorphonuclear neutrophil infiltration, and levels of mitochondrial injury in liver tissues, of the LSEM group were significantly lower than in the LPS group (all p < 0.05). Levels of necroptosis, pyroptosis, apoptosis, and autophagy upregulation in liver tissues in the LSEM group were also significantly lower than in the LPS group (all p < 0.05). Notably, exogenous TNF-α counteracted these effects of SEM18. SEM18 peptide mitigates LPS-induced liver injury in mice.
Collapse
Affiliation(s)
- Chao-Yuan Chang
- Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (C.-Y.C.); (J.F.)
- Integrative Research Center for Critical Care, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
| | - Hao-Jen Hsu
- Department of Life Sciences, College of Medicine, Tzu Chi University, Hualien 970, Taiwan;
| | - Jossen Foo
- Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (C.-Y.C.); (J.F.)
- Integrative Research Center for Critical Care, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan
| | - Hung-Jen Shih
- Integrative Research Center for Critical Care, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan
- Department of Urology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan
- Department of Urology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
- Correspondence: (H.-J.S.); (C.-J.H.)
| | - Chun-Jen Huang
- Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan; (C.-Y.C.); (J.F.)
- Integrative Research Center for Critical Care, Wan Fang Hospital, Taipei Medical University, Taipei 116, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
- Department of Anesthesiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 110, Taiwan
- Correspondence: (H.-J.S.); (C.-J.H.)
| |
Collapse
|
4
|
Wendel M, Heller AR. Mitochondrial function and dysfunction in sepsis. Wien Med Wochenschr 2010; 160:118-23. [PMID: 20364414 DOI: 10.1007/s10354-010-0766-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 01/28/2010] [Indexed: 01/20/2023]
Abstract
Mitochondria are the key source of cellular ATP and their structure and function are markedly affected by pathophysiologic processes associated with the host's response to invading pathogens. In particular, the highly reactive compound peroxynitrite, generated by the reaction of nitric oxide and superoxide anions, inhibits mitochondrial enzymes and damages lipids, proteins, and nucleic acids. Enhanced oxidative stress induces DNA strand breaks that are repaired by activation of poly(ADP-ribose)polymerase (PARP). This process consumes large amounts of nicotinamide adenine dinucleotide (NAD(+)) leading to cellular NAD(+) depletion that impairs flux of reducing equivalents into the respiratory chain and also further promotes inflammation. In experimental studies, novel therapeutic strategies that aim to ameliorate the host's pathogen response or to modulate intracellular signaling events related to oxidative stress protected mitochondrial function and preserved cellular respiration ultimately leading to improved organ function.
Collapse
|
5
|
Saraswathy S, Nguyen AM, Rao NA. The role of TLR4 in photoreceptor {alpha}a crystallin upregulation during early experimental autoimmune uveitis. Invest Ophthalmol Vis Sci 2010; 51:3680-6. [PMID: 20207969 DOI: 10.1167/iovs.09-4575] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Purpose. Previous studies indicate that the upregulation of alphaA crystallin prevents photoreceptor mitochondrial oxidative stress-mediated apoptosis in experimental autoimmune uveitis (EAU). In this study, the role of TLR4 was investigated in the upregulation of alphaA crystallin in the retinas of animals with EAU. Methods. TLR4(-/-), iNOS(-/-), TNF-alpha(-/-), MyD88(-/-), wild-type (WT) control (C57BL/6), and nude mice (B6.Cg-Foxn1(nu)) were immunized with IRBP mixed with complete Freund's adjuvant; eyes were enucleated on day 7 after immunization. Real-time polymerase chain reaction was first used to detect upregulated inflammatory cytokines and alphaA crystallin in retinas with EAU; confirmed with Western blot analysis, and the site of upregulation was localized by immunohistochemistry. Oxidative stress was localized using 8-OHdG, and TUNEL staining was used to detect apoptosis. Results. In early EAU, increased expression of TNF-alpha, iNOS, and alphaA crystallin genes were detected in the retinas of WT mice, whereas such upregulation was absent in TLR4-deficient mice (P < 0.001). alphaA Crystallin was not elevated in MyD88(-/-), TNF-alpha(-/-), and iNOS(-/-) mice with EAU. Immunostaining revealed TNF-alpha, iNOS, and alphaA crystallin localization in the photoreceptor inner segments and outer plexiform layer in the WT controls with EAU; but such staining was absent in TLR4-deficient mice with EAU. 8-OHdG staining showed oxidative stress in the photoreceptors in WT mice with EAU and there was no apoptosis. Conclusions. TLR4 plays an important role in the upregulation of alphaA crystallin through the interaction of MyD88 and the subsequent generation of TNF-alpha and iNOS in the EAU retina. Such crystallin upregulation may prevent oxidative stress-mediated apoptosis of photoreceptors in uveitis.
Collapse
Affiliation(s)
- Sindhu Saraswathy
- Doheny Eye Institute, Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA
| | | | | |
Collapse
|
6
|
Reynolds CM, Suliman HB, Hollingsworth JW, Welty-Wolf KE, Carraway MS, Piantadosi CA. Nitric oxide synthase-2 induction optimizes cardiac mitochondrial biogenesis after endotoxemia. Free Radic Biol Med 2009; 46:564-72. [PMID: 19073249 PMCID: PMC2666005 DOI: 10.1016/j.freeradbiomed.2008.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2008] [Revised: 10/12/2008] [Accepted: 11/06/2008] [Indexed: 11/15/2022]
Abstract
Mitochondrial biogenesis protects metabolism from mitochondrial dysfunction produced by activation of innate immunity by lipopolysaccharide (LPS) or other bacterial products. Here we tested the hypothesis in mouse heart that activation of toll-like receptor-4 (TLR4), which induces early-phase genes that damage mitochondria, also activates mitochondrial biogenesis through induction of nitric oxide synthase (NOS2). We compared three strains of mice: wild type (Wt) C57BL/6J, TLR4(-/-), and NOS2(-/-)for cardiac mitochondrial damage and mitochondrial biogenesis by real-time RT-PCR, Western analysis, immunochemistry, and isoform analysis of myosin heavy chain (MHC) after sublethal heat-killed Escherichia coli (HkEC). After HkEC, Wt mice displayed significant myocardial mtDNA depletion along with enhanced TLR4 and NOS2 gene and protein expression that normalized in 72 h. HkEC generated less cytokine stress in TLR4(-/-)and NOS2(-/-)than Wt mice, NOS2(-/-)mice had mtDNA damage comparable to Wt, and both knockout strains failed to restore mtDNA copy number because of mitochondrial transcriptosome dysfunction. Wt mice also showed the largest beta-MHC isoform switch, but MHC recovery lagged in the NOS2(-/-)and TLR4(-/-)strains. The NOS2(-/-)mice also unexpectedly revealed the codependency of TLR4 expression on NOS2. These findings demonstrate the decisive participation of NOS2 induction by TLR4 in optimization of mitochondrial biogenesis and MHC expression after gram-negative challenge.
Collapse
Affiliation(s)
- Crystal M Reynolds
- Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
| | | | | | | | | | | |
Collapse
|
7
|
Berthiaume F, Barbe L, Mokuno Y, MacDonald AD, Jindal R, Yarmush ML. Steatosis reversibly increases hepatocyte sensitivity to hypoxia-reoxygenation injury. J Surg Res 2008; 152:54-60. [PMID: 18599084 DOI: 10.1016/j.jss.2007.12.784] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Revised: 12/19/2007] [Accepted: 12/26/2007] [Indexed: 12/14/2022]
Abstract
BACKGROUND Steatosis decreases survival of liver grafts after transplantation due to poorly understood mechanisms. We examined the effect of steatosis on the survival of liver grafts in a rat liver transplantation model and the viability of cultured rat hepatocytes after hypoxia and reoxygenation. MATERIALS AND METHODS Rats were fed a choline and methionine-deficient diet to induce hepatic steatosis, and the livers were transplanted into recipient rats after 6 h of cold storage. Cultured hepatocytes were made steatotic by incubation for 3 d in fatty acid-supplemented medium. Hypoxia and reoxygenation were induced by placing the cultures in a 90% N(2)/10% CO(2) atmosphere for 4 h, followed by return to normoxic conditions for 6 h. Hepatocyte viability was assessed by lactate dehydrogenase release and mitochondrial potential staining. RESULTS Transplanted steatotic livers exhibited 0% viability compared with 90% for lean liver controls. When donor choline and methionine-deficient diet rats were returned to a normal diet, hepatic fat content decreased while viability of the grafts after transplantation increased. Cultured steatotic hepatocytes generated more mitochondrial superoxide, exhibited a lowered mitochondrial membrane potential, and released significantly more lactate dehydrogenase after hypoxia and reoxygenation than lean hepatocyte controls. When steatotic hepatocytes were defatted by incubating in fatty acid-free medium, they became less sensitive to hypoxia and reoxygenation as the remaining intracellular triglyceride content decreased. CONCLUSIONS Hepatic steatosis reversibly decreases viability of hepatocytes after hypoxia and reoxygenation in vitro. The decreased viability of steatotic livers after transplantation may be due to a direct effect of hypoxia and reoxygenation on hepatocytes, and can be reversed by defatting.
Collapse
Affiliation(s)
- François Berthiaume
- Center for Engineering in Medicine/Surgical Services, Massachusetts General Hospital, Harvard Medical School, and the Shriners Hospitals for Children, Boston, Massachusetts, USA.
| | | | | | | | | | | |
Collapse
|
8
|
Jiang W, Sun R, Wei H, Tian Z. Toll-like receptor 3 ligand attenuates LPS-induced liver injury by down-regulation of toll-like receptor 4 expression on macrophages. Proc Natl Acad Sci U S A 2005; 102:17077-82. [PMID: 16287979 PMCID: PMC1287976 DOI: 10.1073/pnas.0504570102] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
This study demonstrates that pretreatment with polyinosinic-polycytidylic acid (poly I:C) significantly decreased the mortality and liver injury caused by injection of lipopolysaccharide (LPS) in the presence of d-galactosamine (d-GalN) in C57BL/6 mice. Depletion of natural killer, natural killer T, and T cells did not change the protective effect of poly I:C on LPS/d-GalN-induced liver injury in vivo. However, depletion of macrophages abolished LPS/d-GalN-induced fulminant hepatitis, which could be restored by adoptive transfer of macrophages but not by transfer of poly I:C-treated macrophages. Treatment with poly I:C down-regulated the expression of the toll-like receptor 4 (TLR4) on macrophages and reduced the sensitivity of macrophages (Kupffer cells and peritoneal macrophages from C57BL/6 mice, or RAW264.7 cells) to LPS stimulation. Poly I:C pretreatment also impaired the signaling of mitogen-activated protein kinases and NF-kappaB induced by LPS in RAW264.7 cells. Blockade of TLR3 with a TLR3 antibody abolished poly I:C down-regulation of TLR4 expression and LPS stimulation of TNF-alpha production in RAW264.7 cells. Taken together, our findings suggest that activation of TLR3 by its ligand, poly I:C, induced LPS tolerance by down-regulation of TLR4 expression on macrophages.
Collapse
Affiliation(s)
- Wei Jiang
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei 230027, China
| | | | | | | |
Collapse
|
9
|
Vekemans K, Braet F. Structural and functional aspects of the liver and liver sinusoidal cells in relation to colon carcinoma metastasis. World J Gastroenterol 2005; 11:5095-102. [PMID: 16127736 PMCID: PMC4320379 DOI: 10.3748/wjg.v11.i33.5095] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nowadays, liver metastasis remains difficult to cure. When tumor cells escape and arrive in the liver sinusoids, they encounter the local defense mechanism specific to the liver. The sinusoidal cells have been widely described in physiologic conditions and in relation to metastasis during the past 30 years. This paper provides an “overview” of how these cells function in health and in diseases such as liver metastasis.
Collapse
Affiliation(s)
- Katrien Vekemans
- Centre of Experimental Surgery and Anaesthesia, Abdominal Transplant Surgery Department, Catholic University of Leuven, Herestraat 49, Leuven 3000, Belgium.
| | | |
Collapse
|
10
|
Suliman HB, Welty-Wolf KE, Carraway MS, Schwartz DA, Hollingsworth JW, Piantadosi CA. Toll-like receptor 4 mediates mitochondrial DNA damage and biogenic responses after heat-inactivated E. coli. FASEB J 2005; 19:1531-3. [PMID: 15994412 DOI: 10.1096/fj.04-3500fje] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2005] [Accepted: 04/25/2005] [Indexed: 11/11/2022]
Abstract
An important site of cellular damage in bacterial sepsis is mitochondrial DNA (mtDNA), which we proposed is caused by reactive oxygen and nitrogen species generated by activation of signaling through specific toll-like receptors (TLR). In wild-type (Wt) mice injected with heat-inactivated E. coli, hepatic TLR4 and TLR2 proteins were up-regulated with TLR-dependent increases in transcript levels for tumor necrosis factor (TNF-alpha), interleukin 6, nitric oxide synthase-II (iNOS), and NADPH oxidase 2 (Nox2). The accompanying stress significantly depleted hepatic mtDNA despite eight- and fourfold increases in manganese superoxide dismutase (MnSOD) and mitochondrial transcription factor A (Tfam) expression, respectively. The identical E. coli dose generated significantly less TNF-alpha, NO, and Nox2 in TLR4-/- and TLR2/4-/- but not in TLR2-/- mice. TLR4-/- and TLR2/4-/- compared with Wt mice were protected from mtDNA oxidation but showed no Tfam up-regulation and little copy number restoration. A critical role in the mtDNA damage was determined for TLR4-mediated iNOS transcription through the MyD88 pathway. In Wt mice, mtDNA depletion was avoided by selective iNOS blockade, and residual mtDNA loss was linked to NF-kappaB-dependent TNF-alpha expression. These data disclose the dual role of TLR4 in mtDNA damage and compensatory mitochondrial biogenic responses after innate immune activation.
Collapse
Affiliation(s)
- Hagir B Suliman
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
| | | | | | | | | | | |
Collapse
|
11
|
Seven I, Türközkan N, Cimen B. The effects of nitric oxide synthesis on the Na+ ,K(+)-ATPase activity in guinea pig kidney exposed to lipopolysaccharides. Mol Cell Biochem 2005; 271:107-12. [PMID: 15881661 DOI: 10.1007/s11010-005-5616-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Endotoxins (lipopolysaccharides; LPS) are known to cause multiple organ failure, including renal dysfunction. LPS triggers the synthesis and release of cytokines and the vasodilator nitric oxide (NO*). A major contributor to the increase in NO* production is LPS-stimulated expression of inducible nitric oxide synthase (iNOS). This occurs in vasculature and most organs including the kidney. During endotoxemia, NO* and superoxide react spontaneously to form the potent and versatile oxidant peroxynitrite (ONOO-) and the formation of 3-nitrotyrosine (nTyr)-protein adducts is a reliable biomarker of ONOO- generation. Therefore, the present study was aimed at investigating the role of endogenous nitric oxide in regulating Na+,K(+)-ATPase activity in the kidney, and at investigating the possible contribution of reactive nitrogen species (RNS) by measuring of iNOS activity. In addition, the present study was aimed at investigating the relationship between nTyr formation with iNOS and Na+,K(+)-ATPase activities. Previously in our study, nTyr was not detectable in kidney of normal control animals but was detected markedly in LPS exposed animals. In this study, kidney Na+,K(+)-ATPase activity were maximally inhibited 6 h after LPS injection (P:0.000) and LPS treatment significantly increased iNOS activity of kidney (P:0.000). The regression analysis revealed a very close correlation between Na+,K(+)-ATPase activity and nTyr levels of LPS treated animals (r = -0.868, P = 0.001). Na+,K(+)-ATPase activity were also negatively correlated with iNOS activity (r = -0.877, P = 0.001) in inflamed kidney. These data suggest that NO* and ONOO- contribute to the development of oxidant injury. Furthermore, the source of NO* may be iNOS. iNOS are expressed by the kidney, and their activity may increase following LPS administration. In addition, NO* and ONOO- formation inhibited Na+,K(+)-ATPase activity. This results also have strongly suggested that bacterial LPS disturbs activity of membrane Na+,K(+)-ATPase that may be an important component leading to the pathological consequences such as renal dysfunction in which the production of RNS are increased as in the case of LPS challenge.
Collapse
Affiliation(s)
- Ilgim Seven
- Department of Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey
| | | | | |
Collapse
|
12
|
Liu S, Gallo DJ, Green AM, Williams DL, Gong X, Shapiro RA, Gambotto AA, Humphris EL, Vodovotz Y, Billiar TR. Role of toll-like receptors in changes in gene expression and NF-kappa B activation in mouse hepatocytes stimulated with lipopolysaccharide. Infect Immun 2002; 70:3433-42. [PMID: 12065483 PMCID: PMC128073 DOI: 10.1128/iai.70.7.3433-3442.2002] [Citation(s) in RCA: 205] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The liver is an important site of host-microbe interaction. Although hepatocytes have been reported to be responsive to lipopolysaccharide (LPS), the global gene expression changes by LPS and mechanism(s) by which LPS stimulates cultured hepatocytes remain uncertain. Cultures of primary mouse hepatocytes were incubated with LPS to assess its effects on the global gene expression, hepatic transcription factors, and mitogen-activated protein (MAP) kinase activation. DNA microarray analysis indicated that LPS modulates the selective expression of more than 80 genes and expressed sequence tags. We have shown previously that hepatocytes express CD14, which is required both for uptake and responsiveness to LPS. In other cells, responsiveness to microbial products requires expression of Toll-like receptors (TLR) and their associated accessory molecules. Hepatocytes expressed TLR1 through TLR9 as well as MyD88 and MD-2 transcripts, as shown by reverse transcriptase PCR analysis, indicating that hepatocytes express all known microbe recognition molecules. The MAP kinase extracellular signal-regulated kinase 1/2 was phosphorylated in response to LPS in mouse hepatocytes, and the levels of phosphorylation were lower in hepatocytes from TLR4-null mice. NF-kappa B activation was reduced in TLR4-mutant or -null hepatocytes compared to control hepatocytes, and this defect was partially restored by adenoviral transduction of mouse TLR4. Thus, hepatocytes respond to nanogram concentrations of LPS through a TLR4 response pathway.
Collapse
MESH Headings
- Adaptor Proteins, Signal Transducing
- Adenoviridae
- Animals
- Antigens, Differentiation/genetics
- Antigens, Surface/genetics
- Cells, Cultured
- Drosophila Proteins
- Gene Expression
- Genetic Vectors
- Hepatocytes/cytology
- Hepatocytes/drug effects
- Humans
- Lipopolysaccharides/pharmacology
- Lymphocyte Antigen 96
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/physiology
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3
- Mitogen-Activated Protein Kinases/metabolism
- Myeloid Differentiation Factor 88
- NF-kappa B/metabolism
- Oligonucleotide Array Sequence Analysis
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/physiology
- Receptors, Immunologic/genetics
- Signal Transduction
- Toll-Like Receptor 1
- Toll-Like Receptor 4
- Toll-Like Receptor 9
- Toll-Like Receptors
- Transcription Factor AP-1/metabolism
- Tumor Cells, Cultured
Collapse
Affiliation(s)
- Shubing Liu
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|