1
|
Prohaptoglobin inhibits the transforming growth factor-β-induced epithelial-to-mesenchymal transition in vitro by increasing Smad1/5 activation and suppressing the Smad2/3 signaling pathway in SK-Hep1 liver cancer cells. PLoS One 2022; 17:e0266409. [PMID: 35580109 PMCID: PMC9113573 DOI: 10.1371/journal.pone.0266409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 03/20/2022] [Indexed: 12/24/2022] Open
Abstract
Transforming growth factor-β (TGF-β) is an important inducer of the epithelial-to-mesenchymal transition (EMT) in various cancers. Our previous study demonstrated that prohaptoglobin (proHp) stimulates Smad1/5 activation via ALK1, a TGF-β type I receptor, in endothelial cells, suggesting that proHp plays a role in TGF-β signaling. However, the function of proHp in cellular events downstream of Smads remains unclear. The current study investigated the effects of proHp on TGF-β-mediated Smad-dependent EMT induction and cell invasion in vitro using proHp-overexpressing SK-Hep1 liver cancer cells. The results of Western blotting, quantitative real-time RT-PCR, and immunocytochemistry indicated that proHp downregulated expression of mesenchymal marker and EMT regulator such as N-cadherin, vimentin, and twist, and upregulated expression of the epithelial marker E-cadherin. Compared with control cells, proHp-overexpressing cells exhibited high levels of ALK1/2/3 receptors and markedly increased Smad1/5 phosphorylation. Interestingly, proHp attenuated TGF-β-induced expression of mesenchymal markers and Smad2/3 phosphorylation. It also significantly suppressed cell invasion and migration. Knockdown of Smad1/5 abolished the inhibitory effects of proHp on TGF-β-stimulated Smad2/3 phosphorylation and mesenchymal marker expression. These findings indicate that proHp suppresses the TGF-β-induced EMT and cell invasion in vitro by enhancing Smad1/5 activation via ALK1/2/3 receptors and thus suppressing the Smad2/3 signaling pathway in SK-Hep1 cells. This study suggests that proHp may prevent a de-differentiation of hepatic cells and induce a cell differentiation by regulating the Smad signaling pathway.
Collapse
|
2
|
di Masi A, De Simone G, Ciaccio C, D'Orso S, Coletta M, Ascenzi P. Haptoglobin: From hemoglobin scavenging to human health. Mol Aspects Med 2020; 73:100851. [PMID: 32660714 DOI: 10.1016/j.mam.2020.100851] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 03/23/2020] [Accepted: 03/25/2020] [Indexed: 02/07/2023]
Abstract
Haptoglobin (Hp) belongs to the family of acute-phase plasma proteins and represents the most important plasma detoxifier of hemoglobin (Hb). The basic Hp molecule is a tetrameric protein built by two α/β dimers. Each Hp α/β dimer is encoded by a single gene and is synthesized as a single polypeptide. Following post-translational protease-dependent cleavage of the Hp polypeptide, the α and β chains are linked by disulfide bridge(s) to generate the mature Hp protein. As human Hp gene is characterized by two common Hp1 and Hp2 alleles, three major genotypes can result (i.e., Hp1-1, Hp2-1, and Hp2-2). Hp regulates Hb clearance from circulation by the macrophage-specific receptor CD163, thus preventing Hb-mediated severe consequences for health. Indeed, the antioxidant and Hb binding properties of Hp as well as its ability to stimulate cells of the monocyte/macrophage lineage and to modulate the helper T-cell type 1 and type 2 balance significantly associate with a variety of pathogenic disorders (e.g., infectious diseases, diabetes, cardiovascular diseases, and cancer). Alternative functions of the variants Hp1 and Hp2 have been reported, particularly in the susceptibility and protection against infectious (e.g., pulmonary tuberculosis, HIV, and malaria) and non-infectious (e.g., diabetes, cardiovascular diseases and obesity) diseases. Both high and low levels of Hp are indicative of clinical conditions: Hp plasma levels increase during infections, inflammation, and various malignant diseases, and decrease during malnutrition, hemolysis, hepatic disease, allergic reactions, and seizure disorders. Of note, the Hp:Hb complexes display heme-based reactivity; in fact, they bind several ferrous and ferric ligands, including O2, CO, and NO, and display (pseudo-)enzymatic properties (e.g., NO and peroxynitrite detoxification). Here, genetic, biochemical, biomedical, and biotechnological aspects of Hp are reviewed.
Collapse
Affiliation(s)
- Alessandra di Masi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, I-00146 Roma, Italy
| | - Giovanna De Simone
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, I-00146 Roma, Italy
| | - Chiara Ciaccio
- Department of Clinical Sciences and Translational Medicine, University of Roma "Tor Vergata", Via Montpellier 1, I-00133, Roma, Italy; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems, Via Celso Ulpiani 27, I-70126, Bari, Italy
| | - Silvia D'Orso
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, I-00146 Roma, Italy
| | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Roma "Tor Vergata", Via Montpellier 1, I-00133, Roma, Italy; Interuniversity Consortium for the Research on the Chemistry of Metals in Biological Systems, Via Celso Ulpiani 27, I-70126, Bari, Italy
| | - Paolo Ascenzi
- Interdepartmental Laboratory for Electron Microscopy, Roma Tre University, Via della Vasca Navale 79, I-00146, Roma, Italy.
| |
Collapse
|
3
|
Kiapour AM, Sieker JT, Proffen BL, Lam TT, Fleming BC, Murray MM. Synovial fluid proteome changes in ACL injury-induced posttraumatic osteoarthritis: Proteomics analysis of porcine knee synovial fluid. PLoS One 2019; 14:e0212662. [PMID: 30822327 PMCID: PMC6396923 DOI: 10.1371/journal.pone.0212662] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 02/07/2019] [Indexed: 01/26/2023] Open
Abstract
Surgical transection of the anterior cruciate ligament (ACL) in the porcine model leads to posttraumatic osteoarthritis if left untreated. However, a recently developed surgical treatment, bridge-enhanced ACL repair, prevents further cartilage damage. Since the synovial fluid bathes all the intrinsic structures of knee, we reasoned that a comparative analysis of synovial fluid protein contents could help to better understand the observed chondroprotective effects of the bridge-enhanced ACL repair. We hypothesized that post-surgical changes in the synovial fluid proteome would be different in the untreated and repaired knees, and those changes would correlate with the degree of cartilage damage. Thirty adolescent Yucatan mini-pigs underwent unilateral ACL transection and were randomly assigned to either no further treatment (ACLT, n = 14) or bridge-enhanced ACL repair (BEAR, n = 16). We used an isotopically labeled high resolution LC MS/MS-based proteomics approach to analyze the protein profile of synovial fluid at 6 and 12 months after ACL transection in untreated and repaired porcine knees. A linear mixed effect model was used to compare the normalized protein abundance levels between the groups at each time point. Bivariate linear regression analyses were used to assess the correlations between the macroscopic cartilage damage (total lesion area) and normalized abundance levels of each of the identified secreted proteins. There were no significant differences in cartilage lesion area or quantitative abundance levels of the secreted proteins between the ACLT and BEAR groups at 6 months. However, by 12 months, greater cartilage damage was seen in the ACLT group compared to the BEAR group (p = 0.005). This damage was accompanied by differences in the abundance levels of secreted proteins, with higher levels of Vitamin K-dependent protein C (p = 0.001), and lower levels of Apolipoprotein A4 (p = 0.021) and Cartilage intermediate layer protein 1 (p = 0.049) in the ACLT group compared to the BEAR group. There were also group differences in the secreted proteins that significantly changed in abundance between 6 and 12 months in ACLT and BEAR knees. Increased concentration of Ig lambda-1 chain C regions and decreased concentration of Hemopexin, Clusterin, Coagulation factor 12 and Cartilage intermediate layer protein 1 were associated with greater cartilage lesion area. In general, ACLT knees had higher concentrations of pro-inflammatory proteins and lower concentrations of anti-inflammatory proteins than BEAR group. In addition, the ACLT group had a lower and declining synovial concentrations of CILP, in contrast to a consistently high abundance of CILP in repaired knees. These differences suggest that the knees treated with bridge-enhanced ACL repair may be maintaining an environment that is more protective of the extracellular matrix, a function which is not seen in the ACLT knees.
Collapse
Affiliation(s)
- Ata M. Kiapour
- Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States of America
- * E-mail:
| | - Jakob T. Sieker
- Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Benedikt L. Proffen
- Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States of America
| | - TuKiet T. Lam
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States of America
- MS & Proteomics Resource, W.M. Keck Biotechnology Resource Laboratory, Yale University, New Haven, CT, United States of America
| | - Braden C. Fleming
- Department of Orthopaedics, Warren Alpert Medical School of Brown University & Rhode Island Hospital, Providence, RI, United States of America
| | - Martha M. Murray
- Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States of America
| |
Collapse
|
4
|
Bartlett DB, Connelly MA, AbouAssi H, Bateman LA, Tune KN, Huebner JL, Kraus VB, Winegar DA, Otvos JD, Kraus WE, Huffman KM. A novel inflammatory biomarker, GlycA, associates with disease activity in rheumatoid arthritis and cardio-metabolic risk in BMI-matched controls. Arthritis Res Ther 2016; 18:86. [PMID: 27067270 PMCID: PMC4828830 DOI: 10.1186/s13075-016-0982-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 03/23/2016] [Indexed: 12/31/2022] Open
Abstract
Background RA and CVD both have inflammation as part of the underlying biology. Our objective was to explore the relationships of GlycA, a measure of glycosylated acute phase proteins, with inflammation and cardiometabolic risk in RA, and explore whether these relationships were similar to those for persons without RA. Methods Plasma GlycA was determined for 50 individuals with mild-moderate RA disease activity and 39 controls matched for age, gender, and body mass index (BMI). Regression analyses were performed to assess relationships between GlycA and important markers of traditional inflammation and cardio-metabolic health: inflammatory cytokines, disease activity, measures of adiposity and insulin resistance. Results On average, RA activity was low (DAS-28 = 3.0 ± 1.4). Traditional inflammatory markers, ESR, hsCRP, IL-1β, IL-6, IL-18 and TNF-α were greater in RA versus controls (P < 0.05 for all). GlycA concentrations were significantly elevated in RA versus controls (P = 0.036). In RA, greater GlycA associated with disease activity (DAS-28; RDAS-28 = 0.5) and inflammation (RESR = 0.7, RhsCRP = 0.7, RIL-6 = 0.3: P < 0.05 for all); in BMI-matched controls, these inflammatory associations were absent or weaker (hsCRP), but GlycA was related to IL-18 (RhsCRP = 0.3, RIL-18 = 0.4: P < 0.05). In RA, greater GlycA associated with more total abdominal adiposity and less muscle density (Rabdominal-adiposity = 0.3, Rmuscle-density = −0.3, P < 0.05 for both). In BMI-matched controls, GlycA associated with more cardio-metabolic markers: BMI, waist circumference, adiposity measures and insulin resistance (R = 0.3-0.6, P < 0.05 for all). Conclusions GlycA provides an integrated measure of inflammation with contributions from traditional inflammatory markers and cardio-metabolic sources, dominated by inflammatory markers in persons with RA and cardio-metabolic factors in those without.
Collapse
Affiliation(s)
- David B Bartlett
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA
| | - Margery A Connelly
- LipoScience, Laboratory Corporation of America® Holdings, Raleigh, NC, USA
| | - Hiba AbouAssi
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA
| | - Lori A Bateman
- Center for Health Promotion and Disease Prevention, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - K Noelle Tune
- Center for Health Promotion and Disease Prevention, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Janet L Huebner
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA
| | - Virginia B Kraus
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA
| | - Deborah A Winegar
- LipoScience, Laboratory Corporation of America® Holdings, Raleigh, NC, USA
| | - James D Otvos
- LipoScience, Laboratory Corporation of America® Holdings, Raleigh, NC, USA
| | - William E Kraus
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA
| | - Kim M Huffman
- Department of Medicine and Duke Molecular Physiology Institute, Duke School of Medicine, Durham, NC, USA.
| |
Collapse
|
5
|
Oh MK, Park HJ, Lee JH, Bae HM, Kim IS. Single chain precursor prohaptoglobin promotes angiogenesis by upregulating expression of vascular endothelial growth factor (VEGF) and VEGF receptor2. FEBS Lett 2015; 589:1009-17. [PMID: 25775978 DOI: 10.1016/j.febslet.2015.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 02/27/2015] [Accepted: 03/03/2015] [Indexed: 01/26/2023]
Abstract
Prohaptoglobin (proHp) is processed into mature haptoglobin via site-specific cleavage. Although haptoglobin has been well studied, the functions of proHp remain unclear. We investigated the angiogenic action of proHp in endothelial cells, demonstrating that proHp upregulated vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) expression and endothelial sprouting and branching. ProHp-induced sprouting was attenuated by a VEGFR2 inhibitor. Moreover, proHp was detected in sera of cancer patients by immunoprecipitation and Western blot. These findings indicate that proHp promotes angiogenesis via VEGF/VEGFR2 signalling, and serum proHp level may be a useful biomarker for diseases associated with angiogenesis.
Collapse
Affiliation(s)
- Mi-Kyung Oh
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, Republic of Korea
| | - Hyo-Jung Park
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, Republic of Korea
| | - Joo-Hyun Lee
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, Republic of Korea
| | - Hyun-Mi Bae
- Department of Internal Medicine, Incheon St. Mary's Hospital, The Catholic University of Korea, Incheon 403-720, Republic of Korea
| | - In-Sook Kim
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, Republic of Korea.
| |
Collapse
|
6
|
Park HJ, Oh MK, Kim NH, Cho ML, Kim IS. Identification of a specific haptoglobin C-terminal fragment in arthritic synovial fluid and its effect on interleukin-6 expression. Immunology 2013; 140:133-41. [PMID: 23701120 DOI: 10.1111/imm.12125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 05/20/2013] [Accepted: 05/20/2013] [Indexed: 12/31/2022] Open
Abstract
Haptoglobin (Hp), a major acute-phase plasma protein, has been found in arthritic synovial fluid (SF). However, the function and structural modifications of Hp in arthritic SF are unknown. To investigate in vivo generation of modified Hp associated with inflammatory disease, we examined a new Hp isoform in SF from patients with rheumatoid arthritis (RA). Specific Hp fragments of 28 000 and 15 000 molecular weight were identified in SF of patients with RA, and the two polypeptides were presumed to be fragments of the Hp β-chain (43 000 MW) produced by cleavage with plasmin. The 15 000 MW fragment, which is a C-terminal region of Hp, was observed at higher frequency and levels in RA than in osteoarthritis. Plasmin activity was also higher in SF of RA patients. A recombinant 15 000 MW Hp fragment up-regulated interlukin-6 expression in monocytic cells. These findings indicate that the C-terminal Hp fragment is generated by plasmin in local inflammatory environments and acts as an inflammatory mediator. They further suggest that a specific Hp fragment might be applied as a novel biomarker for the diagnosis and prognosis of inflammatory diseases such as RA.
Collapse
Affiliation(s)
- Hyo Jung Park
- Department of Medical Lifescience, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | | | | | | | | |
Collapse
|
7
|
Yang S, Ma Y, Liu Y, Que H, Zhu C, Liu S. Elevated serum haptoglobin after traumatic brain injury is synthesized mainly in liver. J Neurosci Res 2012; 91:230-9. [DOI: 10.1002/jnr.23159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2012] [Revised: 09/11/2012] [Accepted: 09/20/2012] [Indexed: 11/06/2022]
|
8
|
Mádi A, Majai G, Koy C, Vámosi G, Szántó A, Glocker MO, Fésüs L. Altered sialylation on the cell-surface proteins of dexamethasone-treated human macrophages contributes to augmented uptake of apoptotic neutrophils. Immunol Lett 2010; 135:88-95. [PMID: 20937308 DOI: 10.1016/j.imlet.2010.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 09/22/2010] [Accepted: 10/03/2010] [Indexed: 10/19/2022]
Abstract
Macrophages eliminate apoptotic granulocytes before their secondary necrosis during resolution of inflammation. A well-known glucocorticoid, the anti-inflammatory dexamethasone augments phagocytosis capacity of macrophages with a so far not fully clarified mechanism. We have found that sialylation of cell-surface proteins on human macrophages is markedly altered by dexamethasone. Compared to non-treated cells, dexamethasone-treated macrophages can bind significantly less Sambucus nigra lectin specific for sialic acids on their surfaces as a result of undersialylation of annexin-II and an HLA-II protein. Non-treated macrophages covered by S. nigra lectin had increased uptake of apoptotic cells; however, the significantly higher phagocytosis capacity of dexamethasone-treated macrophages could not be stimulated further this way. Our results suggest that dexamethasone treatment leads to decreased number of sialic acids on the surfaces of human macrophages promoting recognition and uptake of apoptotic cells.
Collapse
Affiliation(s)
- András Mádi
- Apoptosis and Genomics Research Group of the Hungarian Academy of Sciences, Research Centre for Molecular Medicine, Medical Faculty, University of Debrecen, Nagyerdei krt. 98, H-4032 Debrecen, Hungary.
| | | | | | | | | | | | | |
Collapse
|
9
|
Park SJ, Baek SH, Oh MK, Choi SH, Park EH, Kim NH, Shin JC, Kim IS. Enhancement of angiogenic and vasculogenic potential of endothelial progenitor cells by haptoglobin. FEBS Lett 2009; 583:3235-40. [PMID: 19751729 DOI: 10.1016/j.febslet.2009.09.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 09/03/2009] [Accepted: 09/04/2009] [Indexed: 10/20/2022]
Abstract
Endothelial progenitor cells (EPCs) were transfected with the haptoglobin (Hp) gene to investigate the effect of Hp on cell function. Hp potentiated the gene expression of various pro-angiogenic factors in the EPCs. The Hp-modified EPCs also increased in vitro tube formation on Matrigel compared with control cells. In hindlimb ischaemia models, Hp-EPCs showed a greater ability for improving blood perfusion and recovery from ischaemic injury. These results indicate that Hp improves EPC function in neovasculogenesis, which suggests that ex vivo modification of EPCs with the Hp gene can be applied to the treatment of vascular damage.
Collapse
Affiliation(s)
- Seon-Joo Park
- Department of Natural Sciences, College of Medicine, The Catholic University of Korea, Seoul, 137-701, Republic of Korea
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Huntoon KM, Wang Y, Eppolito CA, Barbour KW, Berger FG, Shrikant PA, Baumann H. The acute phase protein haptoglobin regulates host immunity. J Leukoc Biol 2008; 84:170-81. [PMID: 18436583 DOI: 10.1189/jlb.0208100] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The contribution of acute phase plasma proteins to host immune responses remains poorly characterized. To better understand the role of the acute phase reactant and major hemoglobin-binding protein haptoglobin (Hp) on the function of immune cells, we generated Hp-deficient C57BL/6J mice. These mice exhibit stunted development of lymphoid organs associated with lower counts of mature T and B cells in the blood and secondary lymphoid compartments. Moreover, these mice show markedly reduced adaptive immune responses as represented by reduced accumulation of IgG antibody after immunization with adjuvant and nominal antigen, abrogation of Th1-dominated delayed-type hypersensitivity reaction, loss of mitogenic responses mounted by T cells, and reduced T cell responses conveyed by APCs. Collectively, these defects are in agreement with the observations that Hp-deficient mice are not capable of generating a recall response or deterring a Salmonella infection as well as failing to generate tumor antigen-specific responses. The administration of Hp to lymphocytes in tissue culture partially ameliorates these functional defects, lending further support to our contention that the acute phase response protein Hp has the ability to regulate immune cell responses and host immunity. The phenotype of Hp-deficient mice suggests a major regulatory activity for Hp in supporting proliferation and functional differentiation of B and T cells as part of homeostasis and in response to antigen stimulation.
Collapse
Affiliation(s)
- Kristin M Huntoon
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Regulation of haptoglobin expression in a human keratinocyte cell line HaCaT by inflammatory cytokines and dexamethasone. Chin Med J (Engl) 2008. [DOI: 10.1097/00029330-200804020-00014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
|
12
|
Abstract
Apoptosis signal-regulating kinase 1 (ASK1) is a mitogenactivated protein kinase (MAPK) kinase kinase that activates JNK and p38 kinases. ASK1 is activated by various stresses, such as reactive oxygen species (ROS), endoplasmic reticulum (ER) stress, lipopolysaccharide (LPS) and calcium influx which are thought to be responsible for the pathogenesis or exacerbations of various human diseases. Recent studies revealed the involvement of ASK1 in ROS- or ER stressrelated diseases, suggesting that ASK1 may be a potential therapeutic target of various human diseases. In this review, we focus on the current findings for the relationship between pathogenesis and ASK1-MAPK pathways.
Collapse
Affiliation(s)
- Hiroaki Nagai
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
| | | | | | | |
Collapse
|
13
|
Abstract
Haptoglobin (Hp) is a glycoprotein that is produced by hepatic cells and secreted into the circulation. While studying the physiologic functions of Hp, we found that Hp synthesized in THP-1 monocytic cells was largely retained within cells, although Hp is considered a secretory protein. To investigate the molecular mechanism on Hp secretion in THP-1 cells, in the present study, we examined the effect of protein kinase C (PKC) on Hp secretion. When several inhibitors of PKC isoforms were tested, only Rottlerin, a specific inhibitor of PKC-delta, completely blocked Hp secretion from cells to culture medium. To confirm the role of PKC-delta in Hp secretion, Hp-overexpressing COS7 cells were transiently transfected with a wild-type or a dominantnegative mutant of the PKC-delta gene. Mutant PKC-delta significantly inhibited Hp secretion, whereas the wild-type gene slightly increased Hp secretion. These results demonstrate that the PKC-delta signal is involved in Hp secretion.
Collapse
Affiliation(s)
- Mi-Kyung Oh
- Department of Natural Sciences, Chemistry Section, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea
| | | | | | | |
Collapse
|
14
|
Smeets MB, Pasterkamp G, Lim SK, Velema E, van Middelaar B, de Kleijn DPV. Nitric oxide synthesis is involved in arterial haptoglobin expression after sustained flow changes. FEBS Lett 2002; 529:221-4. [PMID: 12372604 DOI: 10.1016/s0014-5793(02)03343-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The acute phase protein haptoglobin is highly expressed in arteries after sustained flow changes and involved in cell migration and arterial restructuring. In the liver, haptoglobin expression is mainly regulated by interleukin-6 (IL-6). In the artery, shear stress and NO influence IL-6 expression. In the present study, we demonstrate that NO synthesis is involved in the regulation of arterial haptoglobin expression after sustained flow changes. Decreased haptoglobin expression after NO inhibition coincided with decreased IL-6 levels. However, IL-6 knockout mice had normal arterial haptoglobin expression levels after sustained flow changes suggesting that other mediators may provide compensatory mechanisms for the regulation of arterial haptoglobin expression.
Collapse
Affiliation(s)
- Mirjam B Smeets
- Experimental Cardiology Laboratory, University Medical Center, Heidelberglaan 100 (room G02.523), 3584 CX Utrecht, The Netherlands
| | | | | | | | | | | |
Collapse
|
15
|
Lee MY, Kim SY, Choi JS, Lee IH, Choi YS, Jin JY, Park SJ, Sung KW, Chun MH, Kim IS. Upregulation of haptoglobin in reactive astrocytes after transient forebrain ischemia in rats. J Cereb Blood Flow Metab 2002; 22:1176-80. [PMID: 12368655 DOI: 10.1097/01.wcb.0000037989.07114.d1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Immunohistochemistry for haptoglobin (Hp) in the postischemic hippocampus demonstrated an immunoreactivity visible one day after reperfusion and continuing to increase until 14 days after ischemia. The immunoreactivity was most prominent in CA1 and the dentate hilar region, especially in cells with astroglial morphology. Double immunofluorescence histochemistry confirmed colocalization of the Hp and glial fibrillary acidic protein. Furthermore, a reverse transcription-polymerase chain reaction study confirmed an elevated Hp mRNA level in the postischemic hippocampus. The Hp gene expression was also upregulated in C6 and A-172 glioblastoma cell lines after H O treatment. These findings suggest that Hp is synthesized in reactive astrocytes in response to ischemia-reperfusion injury.
Collapse
Affiliation(s)
- Mun-Yong Lee
- Department of Anatomy, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Lee IH, Lee JH, Lee MJ, Lee SY, Kim IS. Involvement of CCAAT/enhancer-binding protein alpha in haptoglobin gene expression by all-trans-retinoic acid. Biochem Biophys Res Commun 2002; 294:956-61. [PMID: 12074569 DOI: 10.1016/s0006-291x(02)00581-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Several acute-phase plasma proteins, including haptoglobin (Hp), are induced in the liver in response to inflammation. Recently, we found that Hp gene expression is up-regulated by all-trans-retinoic acid (ATRA) in the extrahepatic monocytic cell line, THP-1. To investigate the molecular mechanism underlying ATRA-induced Hp gene expression, we analyzed the induction of transcription factor CCAAT/enhancer-binding protein (C/EBP) isoforms in ATRA-stimulated THP-1 cells and their binding to the Hp promoter. Western blot analysis showed that treatment with ATRA increased C/EBPalpha and beta expression, but decreased that of C/EBPdelta. Electrophoretic mobility shift and supershift assays demonstrated that only C/EBPalpha of the C/EBP isoforms bound to the C/EBP DNA-binding sites in the Hp promoter. Furthermore, when ATRA-dependent Hp induction was inhibited by sodium butyrate or auranofin, induction of C/EBPalpha, but not C/EBPbeta, was also diminished. These results suggest that C/EBPalpha is involved in the activation of Hp gene expression by ATRA in human monocytic cells.
Collapse
Affiliation(s)
- Il-Ha Lee
- Department of Natural Sciences, Chemistry Section, College of Medicine, Catholic University of Korea, 505 Banpo-Dong, Socho-Gu, Seoul 137-701, Republic of Korea
| | | | | | | | | |
Collapse
|