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Floderer M, Prchal-Murphy M, Vizzardelli C. Dendritic cell-secreted lipocalin2 induces CD8+ T-cell apoptosis, contributes to T-cell priming and leads to a TH1 phenotype. PLoS One 2014; 9:e101881. [PMID: 25010215 PMCID: PMC4092100 DOI: 10.1371/journal.pone.0101881] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 06/12/2014] [Indexed: 01/21/2023] Open
Abstract
Lipocalin 2 (LCN2), which is highly expressed by dendritic cells (DCs) when treated with dexamethasone (Dex) and lipopolysaccharide (LPS), plays a key role in the defence against bacteria and is also involved in the autocrine apoptosis of T-cells. However, the function of LCN2 when secreted by DCs is unknown: this is a critical gap in our understanding of the regulation of innate and adaptive immune systems. Tolerance, stimulation and suppression are functions of DCs that facilitate the fine-tuning of the immune responses and which are possibly influenced by LCN2 secretion. We therefore examined the role of LCN2 in DC/T-cell interaction. WT or Lcn2−/− bone marrow-derived DCs were stimulated with LPS or LPS+IFN-γ with and without Dex and subsequently co-cultured with T-cells from ovalbumin-specific TCR transgenic (OT-I and OT-II) mice. We found that CD8+ T-cell apoptosis was highly reduced when Lcn2−/− DCs were compared with WT. An in vivo CTL assay, using LPS-treated DCs, showed diminished killing ability in mice that had received Lcn2−/− DCs compared with WT DCs. As a consequence, we analysed T-cell proliferation and found that LCN2 participates in T-cell-priming in a dose-dependent manner and promotes a TH1 microenvironment. DC-secreted LCN2, whose function has previously been unknown, may in fact have an important role in regulating the balance between TH1 and TH2. Our results yield insights into DC-secreted LCN2 activity, which could play a pivotal role in cellular immune therapy and in regulating immune responses.
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Affiliation(s)
- Melanie Floderer
- Laboratory of Tumour Immunology, St. Anna Children’s Cancer Research Institute, Vienna, Austria
| | - Michaela Prchal-Murphy
- Institute of Pharmacology and Toxicology, Department for Biomedical Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Caterina Vizzardelli
- Laboratory of Tumour Immunology, St. Anna Children’s Cancer Research Institute, Vienna, Austria
- * E-mail:
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Paragas N, Kulkarni R, Werth M, Schmidt-Ott KM, Forster C, Deng R, Zhang Q, Singer E, Klose AD, Shen TH, Francis KP, Ray S, Vijayakumar S, Seward S, Bovino ME, Xu K, Takabe Y, Amaral FE, Mohan S, Wax R, Corbin K, Sanna-Cherchi S, Mori K, Johnson L, Nickolas T, D'Agati V, Lin CS, Qiu A, Al-Awqati Q, Ratner AJ, Barasch J. α-Intercalated cells defend the urinary system from bacterial infection. J Clin Invest 2014; 124:2963-76. [PMID: 24937428 DOI: 10.1172/jci71630] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 04/24/2014] [Indexed: 12/22/2022] Open
Abstract
α-Intercalated cells (A-ICs) within the collecting duct of the kidney are critical for acid-base homeostasis. Here, we have shown that A-ICs also serve as both sentinels and effectors in the defense against urinary infections. In a murine urinary tract infection model, A-ICs bound uropathogenic E. coli and responded by acidifying the urine and secreting the bacteriostatic protein lipocalin 2 (LCN2; also known as NGAL). A-IC-dependent LCN2 secretion required TLR4, as mice expressing an LPS-insensitive form of TLR4 expressed reduced levels of LCN2. The presence of LCN2 in urine was both necessary and sufficient to control the urinary tract infection through iron sequestration, even in the harsh condition of urine acidification. In mice lacking A-ICs, both urinary LCN2 and urinary acidification were reduced, and consequently bacterial clearance was limited. Together these results indicate that A-ICs, which are known to regulate acid-base metabolism, are also critical for urinary defense against pathogenic bacteria. They respond to both cystitis and pyelonephritis by delivering bacteriostatic chemical agents to the lower urinary system.
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Tung MC, Hsieh SC, Yang SF, Cheng CW, Tsai RT, Wang SC, Huang MH, Hsieh YH. Knockdown of lipocalin-2 suppresses the growth and invasion of prostate cancer cells. Prostate 2013; 73:1281-90. [PMID: 23775308 DOI: 10.1002/pros.22670] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/05/2013] [Indexed: 01/01/2023]
Abstract
BACKGROUND Lipocalin-2 (LCN2) is a member of the lipocalin superfamily, and it has an important role in the regulation of cellular oncogenesis and apoptosis. However, the role for LCN2 in prostate cancer remains unclear. METHOD LCN2 expression has been determined by Western blotting, qRT-PCR, and immunohistochemistry in the human prostate cell lines PC3, DU145, LNCaP, and 22Rv, and in human prostate tissue array. In this study, we identified shRNA-LCN2 to determine the role of LCN2 in prostate-cancer cell proliferation, migration, and invasion. Cell proliferative ability was measured by MTT, colony-formation, and cell-cycle analysis. The role of LCN2 in prostate-cancer cell migration and invasion was analyzed by cell-migration assay and Matrigel invasion assay. The effect of LCN2 knockdown on prostate tumor growth was assessed in a subcutaneous xenograft model. RESULTS LCN2 protein and mRNA expression are higher in PC3 and DU145 cells than in LNCaP and 22Rv cells, and prostate cancer tissue correlated significantly with tumor differentiation (P < 0.017) and Gleason's grade (P < 0.02). LCN2 knockdown in PC3 and DU145 cells decreased cell proliferation, colony formation, cell cycle arrest, migration, and invasion. Conversely, LCN2 overexpression in 22Rv cells produced the opposite effect. Subcutaneous xenografts in mice models showed decreased tumor growth in the LCN2-knockdown mice. CONCLUSIONS Our results suggest that LCN2 might play an important role in regulation of proliferation and invasion of human prostate cancer, and that it can be a valuable marker of prostate cancer progression.
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Affiliation(s)
- Min-Che Tung
- Department of Surgery, Tungs' Taichung Metro Harbor Hospital, Taichung, Taiwan
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Eller K, Schroll A, Banas M, Kirsch AH, Huber JM, Nairz M, Skvortsov S, Weiss G, Rosenkranz AR, Theurl I. Lipocalin-2 expressed in innate immune cells is an endogenous inhibitor of inflammation in murine nephrotoxic serum nephritis. PLoS One 2013; 8:e67693. [PMID: 23861783 PMCID: PMC3701542 DOI: 10.1371/journal.pone.0067693] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/19/2013] [Indexed: 12/12/2022] Open
Abstract
Lipocalin-2 (Lcn-2) is involved in divergent processes such as acute kidney injury or bacterial host defence. Our study was designed to evaluate the functional role of Lcn-2 in nephrotoxic serum nephritis (NTS). Since Lcn-2 is expressed in tubular epithelial cells as well as in cells of innate immunity such as macrophages and polymorphonuclear neutrophils (PMN), we induced NTS in wild-type (WT), Lcn-2 knock-out (KO) mice and WT/Lcn-2 KO chimeras. Mice lacking Lcn-2 exhibited more glomerular damage with increased proteinuria and interstitial leukocyte accumulation compared to WT mice. Chimeras able to express Lcn-2 in macrophages and PMN but not in epithelial cells were found to develop NTS comparable to wild-type controls. In contrast, chimeras expressing Lcn-2 in tubular epithelial cells with no expression in innate immune cells developed increased NTS due to decreased concerted apoptosis but increased necrosis and formation of damage-associated molecular patterns (DAMPs) such as high-mobility group box 1 (HMGB-1) in the kidney. In vivo blockade of HMGB-1, a toll-like receptor (TLR)-2 agonist, significantly reduced inflammation and NTS in Lcn-2 knock-out mice. In parallel, TLR-2 signalling was found to drive Lcn-2 transcription in vitro. Taken together, Lcn-2 expressed in innate immune cells is protective in NTS by inducing concerted apoptosis and inhibiting the formation of HMGB-1 thereby limiting cytokine production via TLR-2 signalling. In parallel, TLR-2 dependent transcription of Lcn-2 is an endogenous inhibitor of inflammation in NTS.
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Affiliation(s)
- Kathrin Eller
- Clinical Division of Nephrology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
- * E-mail: (KE); (IT)
| | - Andrea Schroll
- Clinical Immunology and Infectious Diseases, Department of Internal Medicine VI, Innsbruck Medical University, Innsbruck, Austria
| | - Miriam Banas
- Department of Nephrology, Internal Medicine II, University Hospital Regensburg, Regensburg, Germany
| | - Alexander H. Kirsch
- Clinical Division of Nephrology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - Julia M. Huber
- Laboratory for Molecular Cell Biology, Internal Medicine I, Innsbruck Medical University, Innsbruck, Austria
| | - Manfred Nairz
- Clinical Immunology and Infectious Diseases, Department of Internal Medicine VI, Innsbruck Medical University, Innsbruck, Austria
| | - Sergej Skvortsov
- Department of Therapeutic Radiology and Oncology, Innsbruck Medical University, Innsbruck, Austria
| | - Günter Weiss
- Clinical Immunology and Infectious Diseases, Department of Internal Medicine VI, Innsbruck Medical University, Innsbruck, Austria
| | - Alexander R. Rosenkranz
- Clinical Division of Nephrology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - Igor Theurl
- Clinical Immunology and Infectious Diseases, Department of Internal Medicine VI, Innsbruck Medical University, Innsbruck, Austria
- * E-mail: (KE); (IT)
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Warszawska JM, Gawish R, Sharif O, Sigel S, Doninger B, Lakovits K, Mesteri I, Nairz M, Boon L, Spiel A, Fuhrmann V, Strobl B, Müller M, Schenk P, Weiss G, Knapp S. Lipocalin 2 deactivates macrophages and worsens pneumococcal pneumonia outcomes. J Clin Invest 2013; 123:3363-72. [PMID: 23863624 DOI: 10.1172/jci67911] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 05/02/2013] [Indexed: 11/17/2022] Open
Abstract
Macrophages play a key role in responding to pathogens and initiate an inflammatory response to combat microbe multiplication. Deactivation of macrophages facilitates resolution of the inflammatory response. Deactivated macrophages are characterized by an immunosuppressive phenotype, but the lack of unique markers that can reliably identify these cells explains the poorly defined biological role of this macrophage subset. We identified lipocalin 2 (LCN2) as both a marker of deactivated macrophages and a macrophage deactivator. We show that LCN2 attenuated the early inflammatory response and impaired bacterial clearance, leading to impaired survival of mice suffering from pneumococcal pneumonia. LCN2 induced IL-10 formation by macrophages, skewing macrophage polarization in a STAT3-dependent manner. Pulmonary LCN2 levels were tremendously elevated during bacterial pneumonia in humans, and high LCN2 levels were indicative of a detrimental outcome from pneumonia with Gram-positive bacteria. Our data emphasize the importance of macrophage deactivation for the outcome of pneumococcal infections and highlight the role of LCN2 and IL-10 as determinants of macrophage performance in the respiratory tract.
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Guglani L, Gopal R, Rangel-Moreno J, Junecko BF, Lin Y, Berger T, Mak TW, Alcorn JF, Randall TD, Reinhart TA, Chan YR, Khader SA. Lipocalin 2 regulates inflammation during pulmonary mycobacterial infections. PLoS One 2012. [PMID: 23185529 PMCID: PMC3502292 DOI: 10.1371/journal.pone.0050052] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Pulmonary tuberculosis (TB), caused by the intracellular bacteria Mycobacterium tuberculosis, is a worldwide disease that continues to kill more than 1.5 million people every year worldwide. The accumulation of lymphocytes mediates the formation of the tubercle granuloma in the lung and is crucial for host protection against M.tuberculosis infection. However, paradoxically the tubercle granuloma is also the basis for the immunopathology associated with the disease and very little is known about the regulatory mechanisms that constrain the inflammation associated with the granulomas. Lipocalin 2 (Lcn2) is a member of the lipocalin family of proteins and binds to bacterial siderophores thereby sequestering iron required for bacterial growth. Thus far, it is not known whether Lcn2 plays a role in the inflammatory response to mycobacterial pulmonary infections. In the present study, using models of acute and chronic mycobacterial pulmonary infections, we reveal a novel role for Lcn2 in constraining T cell lymphocytic accumulation and inflammation by inhibiting inflammatory chemokines, such as CXCL9. In contrast, Lcn2 promotes neutrophil recruitment during mycobacterial pulmonary infection, by inducing G-CSF and KC in alveolar macrophages. Importantly, despite a common role for Lcn2 in regulating chemokines during mycobacterial pulmonary infections, Lcn2 deficient mice are more susceptible to acute M.bovis BCG, but not low dose M.tuberculosis pulmonary infection.
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Affiliation(s)
- Lokesh Guglani
- Division of Pulmonary Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Radha Gopal
- Division of Infectious Diseases, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Javier Rangel-Moreno
- Division of Allergy, Immunology and Rheumatology, Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Beth Fallert Junecko
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yinyao Lin
- Division of Infectious Diseases, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Thorsten Berger
- The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, Canada
| | - Tak W. Mak
- The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, Canada
| | - John F. Alcorn
- Division of Pulmonary Medicine, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Troy D. Randall
- Division of Allergy, Immunology and Rheumatology, Department of Medicine, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Todd A. Reinhart
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Yvonne R. Chan
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Shabaana A. Khader
- Division of Infectious Diseases, Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
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Affiliation(s)
- Susan K Fried
- Division of Endocrinology, Diabetes, and Nutrition, Boston University School of Medicine, 650 Albany Street, X815, Boston, Massachusetts 02118, USA.
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Abstract
We have previously characterized lipocalin 2 (Lcn2) as a new adipokine having a critical role in energy and lipid metabolism in male mice. Previous studies by others have suggested that Lcn2 is a putative target gene of estrogens. In this study, we reported the effect of Lcn2 deficiency on estradiol biosynthesis and estrogen receptor signaling in female Lcn2-deficient (Lcn2-/-) mice. We found that Lcn2 expression in white adipose tissue is gender, depot, and age dependent. In female mice, Lcn2 is predominantly expressed in inguinal adipose tissue but at relatively very low levels in perigonadal depot and ovary. After 22 wk of high-fat diet (HFD) feeding or at old age, Lcn2-/- female mice had significantly reduced levels of serum 17β-estradiol and down-regulated expression of estrogen receptor α in multiple metabolic tissues. Consistently, the expression of estrogen-regulated genes involved in cholesterol homeostasis, such as liver X receptor β and low-density lipoprotein receptor was also down-regulated in the adipose tissue of Lcn2-/- mice. These changes were in line with the development of atherogenic dyslipidemia in response to HFD feeding; female Lcn2-/- mice had significantly elevated levels of total cholesterol and low-density lipoprotein cholesterol, whereas reduced high-density lipoprotein cholesterol levels compared with wild-type female mice. Interestingly, when compared with wild-type controls, HFD-fed female Lcn2-/- mice had significantly reduced expression levels of aromatase, a key enzyme regulating estradiol biosynthesis, in adipose tissue. Moreover, Lcn2 deficiency markedly blunted age-related increase in adipose aromatase expression but had no significant impact on age-related reduction in ovarian aromatase expression. Our findings suggest that Lcn2 has a tissue-specific role in adipose estradiol biosynthesis, which may link Lcn2 to obesity- and age-related estradiol production and metabolic complications in females.
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Affiliation(s)
- Hong Guo
- Department of Food Science and Nutrition, University of Minnesota-Twin Cities, St. Paul, Minnesota 55108-1038, USA
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9
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Liu JTC, Song E, Xu A, Berger T, Mak TW, Tse HF, Law IKM, Huang B, Liang Y, Vanhoutte PM, Wang Y. Lipocalin-2 deficiency prevents endothelial dysfunction associated with dietary obesity: role of cytochrome P450 2C inhibition. Br J Pharmacol 2012; 165:520-31. [PMID: 21740414 PMCID: PMC3268203 DOI: 10.1111/j.1476-5381.2011.01587.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2011] [Revised: 06/26/2011] [Accepted: 06/29/2011] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Lipocalin-2 is a pro-inflammatory adipokine up-regulated in obese human subjects and animal models. Its circulating levels are positively correlated with the unfavourable lipid profiles, elevated blood pressure and insulin resistance index. Augmented lipocalin-2 has been found in patients with cardiovascular abnormalities.The present study was designed to investigate the role of lipocalin-2 in regulating endothelial function and vascular reactivity. EXPERIMENTAL APPROACH Wild-type and lipocalin-2 knockout (Lcn2-KO) mice were fed with either a standard chow or a high-fat diet. Blood pressures and endothelium-dependent relaxations/contractions were monitored at 2 week intervals. RESULTS Systolic blood pressure was elevated by high-fat diet in wild-type mice but not in Lcn2-KO mice. Endothelial dysfunction, reflected by the impaired endothelium-dependent relaxations to insulin and augmented endothelium-dependent contractions to ACh, was induced by high-fat diet in wild-type mice. In contrast, Lcn2-KO mice were largely protected from the deterioration of endothelial function caused by dietary challenges. The eNOS dimer/monomer ratio, NO bioavailability, basal and insulin-stimulated PKB/eNOS phosphorylation responses were higher in aortae of Lcn2-KO mice. Administration of lipocalin-2 attenuated endothelium-dependent relaxations to insulin and promoted endothelium-dependent contractions to ACh. It induced eNOS uncoupling and elevated COX expression in the arteries. Treatment with sulphaphenazole, a selective inhibitor of cytochrome P450 2C9, improved endothelial function in wild-type mice and blocked the effects of lipocalin-2 on both endothelium-dependent relaxations to insulin and endothelium-dependent contractions to ACh, as well as eNOS uncoupling. CONCLUSIONS Lipocalin-2, by modulating cytochrome P450 2C9 activity, is critically involved in diet-induced endothelial dysfunction.
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Affiliation(s)
- Jacky TC Liu
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Erfei Song
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Aimin Xu
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
- Department of Medicine, the University of Hong KongHong Kong
| | - Thorsten Berger
- The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health NetworkToronto, Canada
| | - Tak W Mak
- The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health NetworkToronto, Canada
| | - Hung-Fat Tse
- Department of Medicine, the University of Hong KongHong Kong
| | - Ivy KM Law
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Bosheng Huang
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Yan Liang
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Paul M Vanhoutte
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
| | - Yu Wang
- Department of Pharmacology and Pharmacy, the University of Hong KongHong Kong
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10
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Abstract
OBJECTIVE Lipocalin (LCN) 2 belongs to the lipocalin subfamily of low-molecular mass-secreted proteins that bind small hydrophobic molecules. LCN2 has been recently characterized as an adipose-derived cytokine, and its expression is upregulated in adipose tissue in genetically obese rodents. The objective of this study was to investigate the role of LCN2 in diet-induced insulin resistance and metabolic homeostasis in vivo. RESEARCH DESIGN AND METHODS Systemic insulin sensitivity, adaptive thermogenesis, and serum metabolic and lipid profile were assessed in LCN2-deficient mice fed a high-fat diet (HFD) or regular chow diet. RESULTS The molecular disruption of LCN2 in mice resulted in significantly potentiated diet-induced obesity, dyslipidemia, fatty liver disease, and insulin resistance. LCN2(-/-) mice exhibit impaired adaptive thermogenesis and cold intolerance. Gene expression patterns in white and brown adipose tissue, liver, and muscle indicate that LCN2(-/-) mice have increased hepatic gluconeogenesis, decreased mitochondrial oxidative capacity, impaired lipid metabolism, and increased inflammatory state under the HFD condition. CONCLUSIONS LCN2 has a novel role in adaptive thermoregulation and diet-induced insulin resistance.
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Affiliation(s)
- Hong Guo
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis–St. Paul, Minnesota
| | - Daozhong Jin
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis–St. Paul, Minnesota
| | - Yuanyuan Zhang
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis–St. Paul, Minnesota
| | - Wendy Wright
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis–St. Paul, Minnesota; and
| | - Merlijn Bazuine
- Experimental Diabetes, Metabolism, and Nutrition Section, Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - David A. Brockman
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis–St. Paul, Minnesota
| | - David A. Bernlohr
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis–St. Paul, Minnesota; and
| | - Xiaoli Chen
- Department of Food Science and Nutrition, University of Minnesota, Minneapolis–St. Paul, Minnesota
- Corresponding author: Xiaoli Chen,
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Law IK, Xu A, Lam KS, Berger T, Mak TW, Vanhoutte PM, Liu JT, Sweeney G, Zhou M, Yang B, Wang Y. Lipocalin-2 deficiency attenuates insulin resistance associated with aging and obesity. Diabetes 2010; 59:872-82. [PMID: 20068130 PMCID: PMC2844835 DOI: 10.2337/db09-1541] [Citation(s) in RCA: 218] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The proinflammatory cytokines/adipokines produced from adipose tissue act in an autocrine and/or endocrine manner to perpetuate local inflammation and to induce peripheral insulin resistance. The present study investigates whether lipocalin-2 deficiency or replenishment with this adipokine has any impact on systemic insulin sensitivity and the underlying mechanisms. METHODS AND RESULTS Under conditions of aging or dietary-/genetic-induced obesity, lipocalin-2 knockout (Lcn2-KO) mice show significantly decreased fasting glucose and insulin levels and improved insulin sensitivity compared with their wild-type littermates. Despite enlarged fat mass, inflammation and the accumulation of lipid peroxidation products are significantly attenuated in the adipose tissues of Lcn2-KO mice. Adipose fatty acid composition of these mice varies significantly from that in wild-type animals. The amounts of arachidonic acid (C20:4 n6) are elevated by aging and obesity and are paradoxically further increased in adipose tissue, but not skeletal muscle and liver of Lcn2-KO mice. On the other hand, the expression and activity of 12-lipoxygenase, an enzyme responsible for metabolizing arachidonic acid, and the production of tumor necrosis factor-alpha (TNF-alpha), a critical insulin resistance-inducing factor, are largely inhibited by lipocalin-2 deficiency. Lipocalin-2 stimulates the expression and activity of 12-lipoxygenase and TNF-alpha production in fat tissues. Cinnamyl-3,4-dihydroxy-alpha-cyanocinnamate (CDC), an arachidonate lipoxygenase inhibitor, prevents TNF-alpha expression induced by lipocalin-2. Moreover, treatment with TNF-alpha neutralization antibody or CDC significantly attenuated the differences of insulin sensitivity between wild-type and Lcn2-KO mice. CONCLUSIONS Lipocalin-2 deficiency protects mice from developing aging- and obesity-induced insulin resistance largely by modulating 12-lipoxygenase and TNF-alpha levels in adipose tissue.
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Affiliation(s)
- Ivy K.M. Law
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
| | - Aimin Xu
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
- Department of Medicine and Research Center of Heart, Brain, Hormone, and Healthy Aging, the University of Hong Kong, Hong Kong, China
| | - Karen S.L. Lam
- Department of Medicine and Research Center of Heart, Brain, Hormone, and Healthy Aging, the University of Hong Kong, Hong Kong, China
| | - Thorsten Berger
- The Campbell Family Institute for Breast Cancer Research, Princess Margaret Hospital, Toronto, Ontario, Canada
| | - Tak W. Mak
- The Campbell Family Institute for Breast Cancer Research, Princess Margaret Hospital, Toronto, Ontario, Canada
| | - Paul M. Vanhoutte
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
| | - Jacky T.C. Liu
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
| | - Gary Sweeney
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Mingyan Zhou
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
- Department of Medicine and Research Center of Heart, Brain, Hormone, and Healthy Aging, the University of Hong Kong, Hong Kong, China
| | - Bo Yang
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
| | - Yu Wang
- Department of Pharmacology and Pharmacy, the University of Hong Kong, Hong Kong, China
- Department of Medicine and Research Center of Heart, Brain, Hormone, and Healthy Aging, the University of Hong Kong, Hong Kong, China
- Corresponding author: Yu Wang,
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Aigner F, Maier HT, Schwelberger HG, Wallnöfer EA, Amberger A, Obrist P, Berger T, Mak TW, Maglione M, Margreiter R, Schneeberger S, Troppmair J. Lipocalin-2 regulates the inflammatory response during ischemia and reperfusion of the transplanted heart. Am J Transplant 2007; 7:779-88. [PMID: 17391123 DOI: 10.1111/j.1600-6143.2006.01723.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Ischemia and reperfusion (IR) are known to negatively affect early allograft function following solid organ transplantation. Lipocalin-2 (Lcn-2) has been described as a marker and potential positive modulator of acute inflammation during these processes. Using a heterotopic murine heart transplant model we previously found that IR resulted in a pronounced upregulation of Lcn-2 mRNA in the heart at 12 (22.7-fold increase) and 24 h (9.8-fold increase) of reperfusion. We now confirm this increase at the protein level and provide evidence for infiltrating polymorphonuclear cells as the primary source of Lcn-2 protein. Lcn-2 levels are increased 6.6-fold at 12 h, 11.4-fold at 24 h and 6.4 fold at 48 h after reperfusion. In Lcn-2(-/-) grafts the number of infiltrating granulocytes is reduced by 54% (p < 0.05) at 2 h, 79% (p < 0.01) at 12 h, 72% (p < 0.01) at 24 h and 52% (p < 0.01) at 48 h after reperfusion compared to Lcn-2(+/+) grafts, without any differences in cardiomyocyte apoptosis. These data suggest a function of Lcn-2 in the initiation of the inflammatory response. Moreover, an increase in Lcn-2 is not only restricted to the transplanted heart, but is also observed in the kidney, hinting at a possible involvement of Lcn-2 in the systemic response to IR.
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Affiliation(s)
- F Aigner
- Department of General and Transplant Surgery and Daniel-Swarovski-Research Laboratory, Innsbruck Medical University, Austria.
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Fischbach MA, Lin H, Zhou L, Yu Y, Abergel RJ, Liu DR, Raymond KN, Wanner BL, Strong RK, Walsh CT, Aderem A, Smith KD. The pathogen-associated iroA gene cluster mediates bacterial evasion of lipocalin 2. Proc Natl Acad Sci U S A 2006; 103:16502-7. [PMID: 17060628 PMCID: PMC1637611 DOI: 10.1073/pnas.0604636103] [Citation(s) in RCA: 232] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Numerous bacteria cope with the scarcity of iron in their microenvironment by synthesizing small iron-scavenging molecules known as siderophores. Mammals have evolved countermeasures to block siderophore-mediated iron acquisition as part of their innate immune response. Secreted lipocalin 2 (Lcn2) sequesters the Escherichia coli siderophore enterobactin (Ent), preventing E. coli from acquiring iron and protecting mammals from infection by E. coli. Here, we show that the iroA gene cluster, found in many pathogenic strains of Gram-negative enteric bacteria, including E. coli, Salmonella spp., and Klebsiella pneumoniae, allows bacteria to evade sequestration of Ent by Lcn2. We demonstrate that C-glucosylated derivatives of Ent produced by iroA-encoded enzymes do not bind purified Lcn2, and an iroA-harboring strain of E. coli is insensitive to the growth inhibitory effects of Lcn2 in vitro. Furthermore, we show that mice rapidly succumb to infection by an iroA-harboring strain of E. coli but not its wild-type counterpart, and that this increased virulence depends on evasion of host Lcn2. Our findings indicate that the iroA gene cluster allows bacteria to evade this component of the innate immune system, rejuvenating their Ent-mediated iron-acquisition pathway and playing an important role in their virulence.
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Affiliation(s)
- Michael A. Fischbach
- *Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
- Howard Hughes Medical Institute and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Hening Lin
- *Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Lu Zhou
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | - Yang Yu
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | | | - David R. Liu
- Howard Hughes Medical Institute and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | | | - Barry L. Wanner
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
| | - Roland K. Strong
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - Christopher T. Walsh
- *Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
| | - Alan Aderem
- Institute for Systems Biology, Seattle, WA 98103; and
| | - Kelly D. Smith
- **Department of Pathology, University of Washington, Seattle, WA 98195
- To whom correspondence should be addressed. E-mail:
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Knapp S, Florquin S, Golenbock DT, van der Poll T. Pulmonary Lipopolysaccharide (LPS)-Binding Protein Inhibits the LPS-Induced Lung Inflammation In Vivo. J Immunol 2006; 176:3189-95. [PMID: 16493079 DOI: 10.4049/jimmunol.176.5.3189] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
LPS-binding protein (LBP) facilitates the interaction of the Gram-negative cell wall component LPS with CD14, thereby enhancing the immune response to LPS. Although lung epithelial cells have been reported to produce LBP in vitro, knowledge of the in vivo role of pulmonary LBP is limited. Therefore, in the present study we sought to determine the function of pulmonary LBP in lung inflammation induced by intranasal administration of LPS in vivo. Using LBP-deficient (LBP-/-) and normal wild-type mice, we show that the contribution of LBP to pulmonary LPS responsiveness depended entirely on the LPS dose. Although the inflammatory response to low dose (1 ng) LPS was attenuated in LBP-/- mice, neutrophil influx and cytokine/chemokine concentrations in the bronchoalveolar compartment were enhanced in LBP-/- mice treated with higher (>10 ng) LPS doses. This finding was specific for LBP, because the exogenous administration of LBP to LBP-/- mice reversed this phenotype and reduced the local inflammatory response to higher LPS doses. Our results indicate that pulmonary LBP acts as an important modulator of the LPS response in the respiratory tract in vivo. This newly identified function of pulmonary LBP might prove beneficial by enabling a protective immune response to low LPS doses while preventing an overwhelming, potentially harmful immune response to higher doses of LPS.
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Affiliation(s)
- Sylvia Knapp
- Laboratory of Experimental Internal Medicine, Tropical Medicine and AIDS, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Berger T, Togawa A, Duncan GS, Elia AJ, You-Ten A, Wakeham A, Fong HEH, Cheung CC, Mak TW. Lipocalin 2-deficient mice exhibit increased sensitivity to Escherichia coli infection but not to ischemia-reperfusion injury. Proc Natl Acad Sci U S A 2006; 103:1834-9. [PMID: 16446425 PMCID: PMC1413671 DOI: 10.1073/pnas.0510847103] [Citation(s) in RCA: 361] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Diverse functions have been reported for lipocalin 2. To investigate these functions in vivo, we generated gene-targeted lipocalin 2-deficient mice (Lcn2-/- mice). In vitro studies have suggested that lipocalin 2 is important for cellular apoptosis induced by IL-3 withdrawal, and for the induction of kidney differentiation during embryogenesis. Analysis of Lcn2-/- mice showed normal cell death upon IL-3 withdrawal and normal kidney development. However, we found that Lcn2-/- mice exhibited an increased susceptibility to bacterial infections, in keeping with the proposed function of lipocalin 2 in iron sequestration. Neutrophils isolated from Lcn2-/- mice showed significantly less bacteriostatic activity compared with WT controls. The bacteriostatic property of the WT neutrophils was abolished by the addition of exogenous iron, indicating that the main function of lipocalin 2 in the antibacterial innate immune response is to limit this essential element. Another important function ascribed to lipocalin 2 has been its protective role against kidney ischemia-reperfusion injury. We analyzed Lcn2-/- mice using a mouse model for severe renal failure and could not detect any significant differences compared with their WT littermates.
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Affiliation(s)
- Thorsten Berger
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Atsushi Togawa
- Department of Molecular Genetics, Kyoto University Graduate School of Medicine, Shogoin Kawahara-cho 53, Sakyo-ku, Kyoto 606-8507, Japan; and
| | - Gordon S. Duncan
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Andrew J. Elia
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Annick You-Ten
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Andrew Wakeham
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Hannah E. H. Fong
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Carol C. Cheung
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
- Department of Pathology, University Health Network, Toronto, ON, Canada M5G 2C1
| | - Tak W. Mak
- *The Campbell Family Institute for Breast Cancer Research and the Ontario Cancer Institute, University Health Network, Toronto, ON, Canada M5G 2C1
- To whom correspondence should be addressed at:
The Campbell Family Institute for Breast Cancer Research/Ontario Cancer Institute, 620 University Avenue, Suite 706, Toronto, ON, Canada M5G 2C1. E-mail:
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Branger J, Leemans JC, Florquin S, Speelman P, Golenbock DT, van der Poll T. Lipopolysaccharide binding protein-deficient mice have a normal defense against pulmonary mycobacterial infection. Clin Immunol 2005; 116:174-81. [PMID: 15993364 DOI: 10.1016/j.clim.2005.03.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Revised: 02/28/2005] [Accepted: 03/21/2005] [Indexed: 11/20/2022]
Abstract
Lipopolysaccharide (LPS) binding protein (LBP) facilitates the transfer of LPS of Gram-negative bacteria to the pattern recognition receptor CD14, resulting in activation of immunocompetent cells. LBP can also facilitate the binding of lipoarabinomannan, a major cell wall component of mycobacteria, to immune cells. To determine the role of LBP in the immune response to pulmonary Mycobacterium tuberculosis infection, LBP gene-deficient (-/-) and normal wild-type (WT) mice were intranasally infected with M. tuberculosis. LBP-/- mice displayed a similar survival and mycobacterial outgrowth in lungs and liver, although they demonstrated a reduced lymphocyte recruitment and activation during the early stages of infection. The clearance of pulmonary infection with the non-pathogenic M. smegmatis was also unaltered in LBP-/- mice. These data suggest that LBP does not contribute to an effective host response in M. tuberculosis infection.
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Affiliation(s)
- Judith Branger
- Department of Experimental Internal Medicine, Academic Medical Center, Room F4-222, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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Abstract
Mannose Binding Lectin (MBL) is a liver derived, circulating plasma protein that plays a pivotal role in innate immunity. MBL functions as a pathogen recognition molecule, opsonising organisms and initiating the complement cascade. MBL deficiency arising from mutations and promoter polymorphisms in the MBL2 gene is common and has been associated with risk, severity, and frequency of infection in a number of clinical settings. With MBL therapy on the horizon, the usefulness of replacement MBL therapy has been challenged by the notion, that as an acute phase protein, MBL levels may rise under stress to sufficient levels, in individuals who are usually deficient. This report demonstrates that in patients with sepsis and septic shock, the majority of patients do not display an MBL acute phase response: 41.4% of individuals maintained consistent MBL levels throughout hospital stay, 31.3% of individuals demonstrated a positive acute phase response, and a negative acute phase response was observed in 27.3% of individuals studied. Importantly, a positive acute phase response was generally observed in individuals with wild-type MBL2 genes. When a positive acute phase response was observed in individuals with coding mutation, these individuals demonstrated a normal MBL level on admission to hospital. Furthermore, no individual, regardless of genotype who was MBL deficient at admission was able to demonstrate a positive acute phase response into the normal MBL range. These findings indicate MBL demonstrates a variable acute phase response in the clinical setting of sepsis and septic shock.
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Affiliation(s)
- M M Dean
- Co-operative Research Centre for Vaccine Technology, Australian Red Cross Blood Service, Adelaide St, Brisbane, Queensland, Australia.
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Flo TH, Smith KD, Sato S, Rodriguez DJ, Holmes MA, Strong RK, Akira S, Aderem A. Lipocalin 2 mediates an innate immune response to bacterial infection by sequestrating iron. Nature 2004; 432:917-21. [PMID: 15531878 DOI: 10.1038/nature03104] [Citation(s) in RCA: 1317] [Impact Index Per Article: 65.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Accepted: 10/11/2004] [Indexed: 01/11/2023]
Abstract
Although iron is required to sustain life, its free concentration and metabolism have to be tightly regulated. This is achieved through a variety of iron-binding proteins including transferrin and ferritin. During infection, bacteria acquire much of their iron from the host by synthesizing siderophores that scavenge iron and transport it into the pathogen. We recently demonstrated that enterochelin, a bacterial catecholate siderophore, binds to the host protein lipocalin 2 (ref. 5). Here, we show that this event is pivotal in the innate immune response to bacterial infection. Upon encountering invading bacteria the Toll-like receptors on immune cells stimulate the transcription, translation and secretion of lipocalin 2; secreted lipocalin 2 then limits bacterial growth by sequestrating the iron-laden siderophore. Our finding represents a new component of the innate immune system and the acute phase response to infection.
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Affiliation(s)
- Trude H Flo
- Institute for Systems Biology, Seattle, Washington 98103, USA
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Gao Q, Wolfgang MJ, Neschen S, Morino K, Horvath TL, Shulman GI, Fu XY. Disruption of neural signal transducer and activator of transcription 3 causes obesity, diabetes, infertility, and thermal dysregulation. Proc Natl Acad Sci U S A 2004; 101:4661-6. [PMID: 15070774 PMCID: PMC384803 DOI: 10.1073/pnas.0303992101] [Citation(s) in RCA: 296] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Signal transducer and activator of transcription (STAT)3 is widely expressed in the CNS during development and adulthood. STAT3 has been implicated in the control of neuron/glial differentiation and leptin-mediated energy homeostasis, but the physiological role and degree of involvement of STAT3 in these processes is not defined and controversial because of the lack of a direct genetic model. To address this, we created mice with a neural-specific disruption of STAT3 (STAT3(N-/-)). Surprisingly, homozygous mutants were born at the expected Mendelian ratio without apparent developmental abnormalities but susceptible to neonatal lethality. Mutants that survived the neonatal period were hyperphagic, obese, diabetic, and infertile. Administering a melanocortin-3/4 receptor agonist abrogated the hyperphagia and hypothalamic immunohistochemistry showed a marked reduction in proopiomelanocortin with an increase in neuropeptide Y and agouti-related protein. Mutants had reduced energy expenditure and became hypothermic after fasting or cold stress. STAT3(N-/-) mice are hyperleptinemic, suggesting a leptin-resistant condition. Concomitant with neuroendocrine defects such as decreased linear growth and infertility with accompanying increased corticosterone levels, this CNS knockout recapitulates the unique phenotype of db/db and ob/ob obese models and distinguishes them from other genetic models of obesity. Thus, STAT3 in the CNS plays essential roles in the regulation of energy homeostasis and reproduction.
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Affiliation(s)
- Qian Gao
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06520, USA
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Abstract
Mannan-binding protein (MBP) is an acute phase reactant, and its deficiency is associated with the common opsonic defect and suspectibility to infections and atopic constitution. The aim of this study was to investigate the changes occurring in the serum level of MBP in infancy and during later childhood. We studied the serum concentration of MBP in 611 Finnish children of different ages and 110 adults by using an enzyme immunoassay. In an analysis of successive serum samples from infants at the day of birth and at the ages of 1 and 5 months, and at 1 and 2 years, the serum concentration of MBP increased significantly after birth, and was at its highest (the mean and median were 8.13 and 8.49 mgl-1, respectively) at the age of 1 month. After that, it declined to the initial level until the age of 5 months. The MBP concentration continued to decrease during childhood, and after the age of 12 years the MBP values reached the adult level. In Finnish adults the mean and median concentrations of MBP were 4.48 and 4.02 mgl-1, respectively, which seem to be higher than those reported previously in other populations. The high concentration of MBP in infants may best be explained by exposure to novel environmental antigens in early childhood, which suggests a protective role for MBP during the period of immaturity of the immunosystem. In older children the high level of MBP can probably be explained by childhood infections and the ensuing need of MBP.
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Affiliation(s)
- J Aittoniemi
- Department of Clinical Microbiology, Tampere University Hospital, Finland
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Senaldi G, Davies ET, Peakman M, Vergani D, Lu J, Reid KB. Frequency of mannose-binding protein deficiency in patients with systemic lupus erythematosus. Arthritis Rheum 1995; 38:1713-4. [PMID: 7488298 DOI: 10.1002/art.1780381128] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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