1
|
Dai W, Wu J, Li K, Xu Y, Wang W, Xiao W. Andrographolide: A promising therapeutic agent against organ fibrosis. Eur J Med Chem 2024; 280:116992. [PMID: 39454221 DOI: 10.1016/j.ejmech.2024.116992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2024] [Revised: 09/07/2024] [Accepted: 10/19/2024] [Indexed: 10/28/2024]
Abstract
Fibrosis is the terminal pathology of chronic illness in many organs, marked by excessive accumulation of extracellular matrix proteins. These changes influence organ function, ultimately resulting in organ failure. Although significant progress has been achieved in comprehending the molecular pathways responsible for fibrosis in the last decades, effective and approved clinical therapies for the condition are still lacking. Andrographolide is a diterpenoid isolated and purified mainly from the aboveground parts of the Andrographis paniculata plant, which possesses good effects of purging heat, detoxifying, antibacterial and anti-inflammatory. In-depth research has gradually confirmed the anticancer, antioxidant, antiviral and other effects of Andro so that it can play a preventive and therapeutic role in various diseases. Over the past few years, an increasing number of research findings have indicated that Andro exerts antifibrotic effects in various organs by acting on transforming growth factor-β/small mother against decapentaplegic protein, mitogen-activated protein kinases, nuclear factor-E2-related factor 2, nuclear factor kappa-B and other signalling molecules to inhibit inflammation, oxidative stress, epithelial-mesenchymal transition, fibroblast activation and collagen buildup. This review presents a compilation of findings regarding the antifibrotic impact of Andro in tissue and cell models in vitro and in vivo. Emphasis is placed on the potential therapeutic benefits of Andro in diseases related to organ fibrosis. Existing studies and cutting-edge technologies on Andro pharmacokinetics, toxicity and bioavailability are briefly discussed to provide evidence for accelerating its clinical conversion and adoption.
Collapse
Affiliation(s)
- Wei Dai
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China.
| | - Jiabin Wu
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China.
| | - Ke Li
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China.
| | - Yingying Xu
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China.
| | - Wenhong Wang
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China; Research Institute for Biology and Medicine, Hunan University of Medicine, Huaihua 418000, China.
| | - Weihua Xiao
- Shanghai Key Lab of Human Performance(Shanghai University of Sport), Shanghai University of Sport, Shanghai 200438, China; The Key Lab of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai 200438, China.
| |
Collapse
|
2
|
Gamart J, Barozzi I, Laurent F, Reinhardt R, Martins LR, Oberholzer T, Visel A, Zeller R, Zuniga A. SMAD4 target genes are part of a transcriptional network that integrates the response to BMP and SHH signaling during early limb bud patterning. Development 2021; 148:273522. [PMID: 34822715 PMCID: PMC8714076 DOI: 10.1242/dev.200182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/03/2021] [Indexed: 12/13/2022]
Abstract
SMAD4 regulates gene expression in response to BMP and TGFβ signal transduction, and is required for diverse morphogenetic processes, but its target genes have remained largely elusive. Here, we identify the SMAD4 target genes in mouse limb buds using an epitope-tagged Smad4 allele for ChIP-seq analysis in combination with transcription profiling. This analysis shows that SMAD4 predominantly mediates BMP signal transduction during early limb bud development. Unexpectedly, the expression of cholesterol biosynthesis enzymes is precociously downregulated and intracellular cholesterol levels are reduced in Smad4-deficient limb bud mesenchymal progenitors. Most importantly, our analysis reveals a predominant function of SMAD4 in upregulating target genes in the anterior limb bud mesenchyme. Analysis of differentially expressed genes shared between Smad4- and Shh-deficient limb buds corroborates this function of SMAD4 and also reveals the repressive effect of SMAD4 on posterior genes that are upregulated in response to SHH signaling. This analysis uncovers opposing trans-regulatory inputs from SHH- and SMAD4-mediated BMP signal transduction on anterior and posterior gene expression during the digit patterning and outgrowth in early limb buds. Summary: The transcriptional targets of SMAD4 in early limb buds are identified and the largely opposing impact of BMP and SHH signaling on early digit patterning and outgrowth is revealed.
Collapse
Affiliation(s)
- Julie Gamart
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Iros Barozzi
- Functional Genomics Department, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Frédéric Laurent
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Robert Reinhardt
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Laurène Ramos Martins
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Thomas Oberholzer
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Axel Visel
- Functional Genomics Department, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.,US Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA.,School of Natural Sciences, University of California, Merced, CA 95343, USA
| | - Rolf Zeller
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| | - Aimée Zuniga
- Developmental Genetics, Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
| |
Collapse
|
3
|
Seong CH, Chiba N, Kusuyama J, Subhan Amir M, Eiraku N, Yamashita S, Ohnishi T, Nakamura N, Matsuguchi T. Bone morphogenetic protein 9 (BMP9) directly induces Notch effector molecule Hes1 through the SMAD signaling pathway in osteoblasts. FEBS Lett 2020; 595:389-403. [PMID: 33264418 DOI: 10.1002/1873-3468.14016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 11/01/2020] [Accepted: 11/18/2020] [Indexed: 12/24/2022]
Abstract
Bone morphogenetic protein (BMP) 9 is one of the most osteogenic BMPs, but its mechanism of action has not been fully elucidated. Hes1, a transcriptional regulator with a basic helix-loop-helix domain, is a well-known effector of Notch signaling. Here, we find that BMP9 induces periodic increases of Hes1 mRNA and protein expression in osteoblasts, presumably through an autocrine negative feedback mechanism. BMP9-mediated Hes1 induction is significantly inhibited by an ALK inhibitor and overexpression of Smad7, an inhibitory Smad. Luciferase and ChIP assays revealed that two Smad-binding sites in the 5' upstream region of the mouse Hes1 gene are essential for transcriptional activation by BMP9. Thus, our data indicate that BMP9 induces Hes1 expression in osteoblasts via the Smad signaling pathway.
Collapse
Affiliation(s)
- Chang-Hwan Seong
- Department of Oral and Maxillofacial Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.,Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Norika Chiba
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Joji Kusuyama
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.,Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Department of Medicine, Harvard Medical School, Boston, MA, USA.,Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan
| | - Muhammad Subhan Amir
- Department of Oral and Maxillofacial Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.,Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.,Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Airlangga University, Surabaya, Indonesia
| | - Nahoko Eiraku
- Department of Periodontology, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Sachiko Yamashita
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Tomokazu Ohnishi
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Norifumi Nakamura
- Department of Oral and Maxillofacial Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| | - Tetsuya Matsuguchi
- Department of Oral Biochemistry, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
| |
Collapse
|
4
|
Zhu T, Ma Z, Wang H, Jia X, Wu Y, Fu L, Li Z, Zhang C, Yu G. YAP/TAZ affects the development of pulmonary fibrosis by regulating multiple signaling pathways. Mol Cell Biochem 2020; 475:137-149. [PMID: 32813142 DOI: 10.1007/s11010-020-03866-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/31/2020] [Indexed: 12/20/2022]
Abstract
YAP and TAZ are important co-activators of various biological processes in human body. YAP/TAZ plays a vital role in the development of pulmonary fibrosis. Dysregulation of the YAP/TAZ signaling pathway is one of the most important causes of pulmonary fibrosis. Therefore, considering its crucial role, summary of the signal mechanism of YAP/TAZ is of certain guiding significance for the research of YAP/TAZ as a therapeutic target. The present review provided a detailed introduction to various YAP/TAZ-related signaling pathways and clarified the specific role of YAP/TAZ in these pathways. In the meantime, we summarized and evaluated possible applications of YAP/TAZ in the treatment of pulmonary fibrosis. Overall, our study is of guiding significance for future research on the functional mechanism of YAP/TAZ underlying lung diseases as well as for identification of novel therapeutic targets specific to pulmonary fibrosis.
Collapse
Affiliation(s)
- Ting Zhu
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Zhifeng Ma
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Haiyong Wang
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Xiaoxiao Jia
- Department of Pathology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), Shaoxing, 312000, China
| | - Yuanlin Wu
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Linhai Fu
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Zhupeng Li
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China
| | - Chu Zhang
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China.
| | - Guangmao Yu
- Department of Thoracic Surgery, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), No. 568 Zhongxing North Road, Yuecheng District, Shaoxing, 312000, China.
| |
Collapse
|
5
|
Aly H, Mansi Y, Ez El Din Z, Gabr Metwally H, Sabry A. Mesenchymal stromal cells and TGF-β1 in tracheal aspirate of premature infants: early predictors for bronchopulmonary dysplasia? J Perinat Med 2019; 47:470-477. [PMID: 30789824 DOI: 10.1515/jpm-2018-0305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 01/10/2019] [Indexed: 11/15/2022]
Abstract
Background The pathogenesis of bronchopulmonary dysplasia (BPD) includes arrest of alveolar septation and enhanced fibrosis. We hypothesized that mesenchymal stromal cells (MSC) and transforming growth factor-β1 (TGF-β1) in tracheal aspirates of mechanically ventilated premature infants differ in BPD and non-BPD infants. Methods Tracheal aspirates were collected during the first week of life. Mononuclear cells were separated, cultured and immunophenotyped by flow cytometry. MSCs colony/cluster ratio was calculated as an index for dysplastic potentials. TGF-β1 was assessed by enzyme-linked immunosorbent assay (ELISA). Setting: Neonatal intensive care unit. Patients Premature infants at risk for BPD. Results A total of 121 preterm infants were enrolled; 27 of them died and among the 94 survivors 23 infants had BPD. MSCs were identified in younger [gestational age (GA): 30.9±1.7 vs. 31.8±1.8, P=0.025] and smaller [birth weight (BW): 1.3±0.28 vs. 1.44±0.37 kg, P=0.04] infants with lower Apgar scores. The recovery rate of MSCs in BPD and non-BPD groups did not differ. BPD group had significantly smaller colony/cluster ratio compared to non-BPD (0.97 vs. 4.25, P=0.002). TGF-β1 was significantly greater in BPD infants (4173.9±864.3 vs. 3705.8±540.5 pg/mL, P=0.021). Conclusion Infants with BPD had different MSCs morphology and greater TGF-β1 expression. The pathogenesis for these morphological changes of resident lung MSCs needs further studying.
Collapse
Affiliation(s)
- Hany Aly
- Department of Neonatology, Cleveland Clinic Children's Hospital, 9500 Euclid Avenue, M31-37, Cleveland, OH 44195, USA
| | - Yasmeen Mansi
- Division of Neonatology, Department of Pediatrics, Cairo University Children's Hospital, Cairo, Egypt
| | - Zahraa Ez El Din
- Division of Neonatology, Department of Pediatrics, Cairo University Children's Hospital, Cairo, Egypt
| | - Hala Gabr Metwally
- Division of Hematology, Department of Pediatrics, Cairo University Children's Hospital, Cairo, Egypt
| | - Amira Sabry
- Division of Neonatology, Department of Pediatrics, Cairo University Children's Hospital, Cairo, Egypt
| |
Collapse
|
6
|
SMAD6 overexpression leads to accelerated myogenic differentiation of LMNA mutated cells. Sci Rep 2018; 8:5618. [PMID: 29618840 PMCID: PMC5884786 DOI: 10.1038/s41598-018-23918-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 03/22/2018] [Indexed: 12/23/2022] Open
Abstract
LMNA gene encodes lamins A and C, two major components of the nuclear lamina, a network of intermediate filaments underlying the inner nuclear membrane. Most of LMNA mutations are associated with cardiac and/or skeletal muscles defects. Muscle laminopathies include Emery-Dreifuss Muscular Dystrophy, Limb-Girdle Muscular Dystrophy 1B, LMNA-related Congenital Muscular Dystrophy and Dilated Cardiomyopathy with conduction defects. To identify potential alterations in signaling pathways regulating muscle differentiation in LMNA-mutated myoblasts, we used a previously described model of conditionally immortalized murine myoblasts: H-2K cell lines. Comparing gene expression profiles in wild-type and Lmna∆8–11 H-2K myoblasts, we identified two major alterations in the BMP (Bone Morphogenetic Protein) pathway: Bmp4 downregulation and Smad6 overexpression. We demonstrated that these impairments lead to Lmna∆8–11 myoblasts premature differentiation and can be rescued by downregulating Smad6 expression. Finally, we showed that BMP4 pathway defects are also present in myoblasts from human patients carrying different heterozygous LMNA mutations.
Collapse
|
7
|
TGF-β Family Signaling in Ductal Differentiation and Branching Morphogenesis. Cold Spring Harb Perspect Biol 2018; 10:cshperspect.a031997. [PMID: 28289061 DOI: 10.1101/cshperspect.a031997] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Epithelial cells contribute to the development of various vital organs by generating tubular and/or glandular architectures. The fully developed forms of ductal organs depend on processes of branching morphogenesis, whereby frequency, total number, and complexity of the branching tissue define the final architecture in the organ. Some ductal tissues, like the mammary gland during pregnancy and lactation, disintegrate and regenerate through periodic cycles. Differentiation of branched epithelia is driven by antagonistic actions of parallel growth factor systems that mediate epithelial-mesenchymal communication. Transforming growth factor-β (TGF-β) family members and their extracellular antagonists are prominently involved in both normal and disease-associated (e.g., malignant or fibrotic) ductal tissue patterning. Here, we discuss collective knowledge that permeates the roles of TGF-β family members in the control of the ductal tissues in the vertebrate body.
Collapse
|
8
|
Guo H, Zhang Z, Su Z, Sun C, Zhang X, Zhao X, Lai X, Su Z, Li Y, Zhan JY. Enhanced anti-tumor activity and reduced toxicity by combination andrographolide and bleomycin in ascitic tumor-bearing mice. Eur J Pharmacol 2016; 776:52-63. [DOI: 10.1016/j.ejphar.2016.02.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/05/2016] [Accepted: 02/09/2016] [Indexed: 01/02/2023]
|
9
|
Zhang Y, Wang S, Liu S, Li C, Wang J. Role of Smad signaling in kidney disease. Int Urol Nephrol 2015; 47:1965-75. [DOI: 10.1007/s11255-015-1115-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 09/18/2015] [Indexed: 01/21/2023]
|
10
|
Mahoney JE, Mori M, Szymaniak AD, Varelas X, Cardoso WV. The hippo pathway effector Yap controls patterning and differentiation of airway epithelial progenitors. Dev Cell 2014; 30:137-50. [PMID: 25043473 DOI: 10.1016/j.devcel.2014.06.003] [Citation(s) in RCA: 186] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 04/09/2014] [Accepted: 06/06/2014] [Indexed: 01/08/2023]
Abstract
How epithelial progenitor cells integrate local signals to balance expansion with differentiation during organogenesis is still little understood. Here, we provide evidence that the Hippo pathway effector Yap is a key regulator of this process in the developing lung. We show that when epithelial tubules are forming and branching, a nucleocytoplasmic shift in Yap localization marks the boundary between the airway and the distal lung compartments. At this transition zone, Yap specifies a transcriptional program that controls Sox2 expression and ultimately generates the airway epithelium. Without Yap, epithelial progenitors are unable to properly respond to local TGF-β-induced cues and control levels and distribution of Sox2 to form airways. Yap levels and subcellular localization also markedly influence Sox2 expression and differentiation of adult airway progenitors. Our data reveal a role for the Hippo-Yap pathway in integrating growth-factor-induced cues in the developing and adult lung potentially key for homeostasis and regeneration repair.
Collapse
Affiliation(s)
- John E Mahoney
- Columbia Center for Human Development, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA; Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA; Department of Pathology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Munemasa Mori
- Columbia Center for Human Development, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | | | - Xaralabos Varelas
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | - Wellington V Cardoso
- Columbia Center for Human Development, Department of Medicine, Columbia University Medical Center, New York, NY 10032, USA; Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA; Department of Pathology, Boston University School of Medicine, Boston, MA 02118, USA.
| |
Collapse
|
11
|
Bugyei-Twum A, Advani A, Advani SL, Zhang Y, Thai K, Kelly DJ, Connelly KA. High glucose induces Smad activation via the transcriptional coregulator p300 and contributes to cardiac fibrosis and hypertrophy. Cardiovasc Diabetol 2014; 13:89. [PMID: 24886336 PMCID: PMC4108062 DOI: 10.1186/1475-2840-13-89] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 04/23/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Despite advances in the treatment of heart failure, mortality remains high, particularly in individuals with diabetes. Activated transforming growth factor beta (TGF-β) contributes to the pathogenesis of the fibrotic interstitium observed in diabetic cardiomyopathy. We hypothesized that high glucose enhances the activity of the transcriptional co-activator p300, leading to the activation of TGF-β via acetylation of Smad2; and that by inhibiting p300, TGF-β activity will be reduced and heart failure prevented in a clinically relevant animal model of diabetic cardiomyopathy. METHODS p300 activity was assessed in H9c2 cardiomyoblasts under normal glucose (5.6 mmol/L-NG) and high glucose (25 mmol/L-HG) conditions. 3H-proline incorporation in cardiac fibroblasts was also assessed as a marker of collagen synthesis. The role of p300 activity in modifying TGF-β activity was investigated with a known p300 inhibitor, curcumin or p300 siRNA in vitro, and the functional effects of p300 inhibition were assessed using curcumin in a hemodynamically validated model of diabetic cardiomyopathy - the diabetic TG m(Ren-2)27 rat. RESULTS In vitro, H9c2 cells exposed to HG demonstrated increased p300 activity, Smad2 acetylation and increased TGF-β activity as assessed by Smad7 induction (all p < 0.05 c/w NG). Furthermore, HG induced 3H-proline incorporation as a marker of collagen synthesis (p < 0.05 c/w NG). p300 inhibition, using either siRNA or curcumin reduced p300 activity, Smad acetylation and TGF-β activity (all p < 0.05 c/w vehicle or scrambled siRNA). Furthermore, curcumin therapy reduced 3H-proline incorporation in HG and TGF-β stimulated fibroblasts (p < 0.05 c/w NG). To determine the functional significance of p300 inhibition, diabetic Ren-2 rats were randomized to receive curcumin or vehicle for 6 weeks. Curcumin treatment reduced cardiac hypertrophy, improved diastolic function and reduced extracellular matrix production, without affecting glycemic control, along with a reduction in TGF-β activity as assessed by Smad7 activation (all p < 0.05 c/w vehicle treated diabetic animals). CONCLUSIONS These findings suggest that high glucose increases the activity of the transcriptional co-regulator p300, which increases TGF-β activity via Smad2 acetylation. Modulation of p300 may be a novel strategy to treat diabetes induced heart failure.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Kim A Connelly
- Keenan Research Centre for Biomedical Science, St, Michael's Hospital, 209 Victoria Street, Toronto, ON M5B 1T8, Canada.
| |
Collapse
|
12
|
Liu W, Shi R, Yang W, Zhao N, Du Y, Zou Y, Yu W. Synchronous alteration pattern between serine-threonine kinase receptor-associated protein and Smad7 in pilocarpine-induced rats of epilepsy. Synapse 2014; 68:275-82. [PMID: 24577865 DOI: 10.1002/syn.21739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2013] [Revised: 01/19/2014] [Accepted: 02/16/2014] [Indexed: 11/09/2022]
Abstract
PURPOSE Recent studies have shown that transforming growth factor β (TGFβ) signaling participates in the epileptogenesis. Serine-threonine kinase receptor-associated protein (STRAP) and Smad7 synergize in the inhibition of the TGFβ signaling. The aim of the present study was to determine the expression pattern of STRAP and Smad7 in the hippocampus and temporal lobe cortex of pilocarpine-induced rats models of epilepsy. METHODS Lithium chloride-pilocarpine-induced rats with status epilepticus (SE) were established. Total of 60 male Sprague-Dawley rats was used as control (n = 10), 24 h (n = 10), 72 h (n = 10), 1 week (n = 10), 1 month (n = 10), and 2 months (n = 10) after pilocarpine-induced SE, respectively. We detected the expression levels of STRAP and Smad7 in the hippocampus and temporal lobe cortex of rats at the aforementioned time points using western blotting and immunohistochemistry. RESULTS STRAP level was significantly decreased in 24 h, 72 h (acute stage), 1 week (latent stage), 1 month, 2 months (chronic stage), respectively, in the rat models compared with the control rats by using both western blotting and immunohistochemistry. Smad7 had similar reduced pattern as STRAP. CONCLUSIONS Our results indicate that STRAP and Smad7 proteins might be involved in the development of temporal lobe epilepsy.
Collapse
Affiliation(s)
- Wei Liu
- Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016, China
| | | | | | | | | | | | | |
Collapse
|
13
|
Kim TA, Kang JM, Hyun JS, Lee B, Kim SJ, Yang ES, Hong S, Lee HJ, Fujii M, Niederhuber JE, Kim SJ. The Smad7-Skp2 complex orchestrates Myc stability, impacting on the cytostatic effect of TGF-β. J Cell Sci 2013; 127:411-21. [PMID: 24259667 DOI: 10.1242/jcs.136028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In most human cancers the Myc proto-oncogene is highly activated. Dysregulation of Myc oncoprotein contributes to tumorigenesis in numerous tissues and organs. Thus, targeting Myc stability could be a crucial step for cancer therapy. Here we report Smad7 as a key molecule regulating Myc stability and activity by recruiting the F-box protein, Skp2. Ectopic expression of Smad7 downregulated the protein level of Myc without affecting the transcription level, and significantly repressed its transcriptional activity, leading to inhibition of cell proliferation and tumorigenic activity. Furthermore, Smad7 enhanced ubiquitylation of Myc through direct interaction with Myc and recruitment of Skp2. Ablation of Smad7 resulted in less sensitivity to the growth inhibitory effect of TGF-β by inducing stable Myc expression. In conclusion, these findings that Smad7 functions in Myc oncoprotein degradation and enhances the cytostatic effect of TGF-β signaling provide a possible new therapeutic approach for cancer treatment.
Collapse
Affiliation(s)
- Tae-Aug Kim
- CHA Cancer Institute, CHA University, Seoul 135-081, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Regulatory interactions between androgens, Hoxb5, and TGF β signaling in murine lung development. BIOMED RESEARCH INTERNATIONAL 2013; 2013:320249. [PMID: 24078914 PMCID: PMC3776362 DOI: 10.1155/2013/320249] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 07/17/2013] [Indexed: 12/25/2022]
Abstract
Androgens enhance airway branching but delay alveolar maturation contributing to increased respiratory morbidity in prematurely born male infants. Hoxb5 protein positively regulates airway branching in developing lung. In other organs, androgen regulation intersects with Hox proteins and TGFβ-SMAD signaling, but these interactions have not been studied in the lung. We hypothesized that androgen alteration of airway branching early in lung development requires Hoxb5 expression and that these androgen-Hoxb5 interactions occur partially through regional changes in TGFβ signaling. To evaluate acute effects of androgen and TGFβ on Hoxb5, E11 whole fetal mouse lungs were cultured with dihydrotestosterone (DHT) with/without Hoxb5 siRNA or TGFβ inhibitory antibody. Chronic in utero DHT exposure was accomplished by exposing pregnant mice to DHT (subcutaneous pellet) from E11 to E18. DHT's ability to enhance airway branching and alter phosphorylated SMAD2 cellular localization was partially dependent on Hoxb5. Hoxb5 inhibition also changed the cellular distribution of SMAD7 protein. Chronic in utero DHT increased Hoxb5 and altered SMAD7 mesenchymal localization. TGFβ inhibition enhanced airway branching, and Hoxb5 protein cellular localization was more diffuse. We conclude that DHT controls lung airway development partially through modulation of Hoxb5 protein expression and that this level of regulation involves interactions with TGFβ signaling.
Collapse
|
15
|
Höhne K, Schließmann SJ, Kirschbaum A, Plönes T, Müller-Quernheim J, Tenor H, Zissel G. Roflumilast-N-oxide induces surfactant protein expression in human alveolar epithelial cells type II. PLoS One 2012; 7:e38369. [PMID: 22815690 PMCID: PMC3398032 DOI: 10.1371/journal.pone.0038369] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 05/04/2012] [Indexed: 11/18/2022] Open
Abstract
Surfactant proteins (SPs) are important lipoprotein complex components, expressed in alveolar epithelial cells type II (AEC-II), and playing an essential role in maintenance of alveolar integrity and host defence. Because expressions of SPs are regulated by cyclic adenosine monophosphate (cAMP), we hypothesized that phosphodiesterase (PDE) inhibitors, influence SP expression and release. Analysis of PDE activity of our AEC-II preparations revealed that PDE4 is the major cAMP hydrolysing PDE in human adult AEC-II. Thus, freshly isolated human AEC-II were stimulated with two different concentrations of the PDE4 inhibitor roflumilast-N-oxide (3 nM and 1 µM) to investigate the effect on SP expression. SP mRNA levels disclosed a large inter-individual variation. Therefore, the experiments were grouped by the basal SP expression in low and high expressing donors. AEC-II stimulated with Roflumilast-N-oxide showed a minor increase in SP-A1, SP-C and SP-D mRNA mainly in low expressing preparations. To overcome the effects of different basal levels of intracellular cAMP, cyclooxygenase was blocked by indomethacin and cAMP production was reconstituted by prostaglandin E2 (PGE2). Under these conditions SP-A1, SP-A2, SP-B and SP-D are increased by roflumilast-N-oxide in low expressing preparations. Roflumilast-N-oxide fosters the expression of SPs in human AEC-II via increase of intracellular cAMP levels potentially contributing to improved alveolar host defence and enhanced resolution of inflammation.
Collapse
Affiliation(s)
- Kerstin Höhne
- Division of Internal Medicine, Department of Pneumology, University Medical Centre, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Stephan J. Schließmann
- Division of Internal Medicine, Department of Pneumology, University Medical Centre, Freiburg, Germany
| | - Andreas Kirschbaum
- Division of Surgery, Department of Thoracic Surgery, University Medical Centre, Freiburg, Germany
| | - Till Plönes
- Division of Surgery, Department of Thoracic Surgery, University Medical Centre, Freiburg, Germany
| | - Joachim Müller-Quernheim
- Division of Internal Medicine, Department of Pneumology, University Medical Centre, Freiburg, Germany
| | - Hermann Tenor
- Nycomed GmbH Global Discovery, Nycomed GmbH, Konstanz, Germany
| | - Gernot Zissel
- Division of Internal Medicine, Department of Pneumology, University Medical Centre, Freiburg, Germany
- * E-mail:
| |
Collapse
|
16
|
Gleghorn JP, Kwak J, Pavlovich AL, Nelson CM. Inhibitory morphogens and monopodial branching of the embryonic chicken lung. Dev Dyn 2012; 241:852-62. [PMID: 22410853 DOI: 10.1002/dvdy.23771] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2012] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Branching morphogenesis generates a diverse array of epithelial patterns, including dichotomous and monopodial geometries. Dichotomous branching can be instructed by concentration gradients of epithelial-derived inhibitory morphogens, including transforming growth factor-β (TGFβ), which is responsible for ramification of the pubertal mammary gland. Here, we investigated the role of autocrine inhibitory morphogens in monopodial branching morphogenesis of the embryonic chicken lung. RESULTS Computational modeling and experiments using cultured organ explants each separately revealed that monopodial branching patterns cannot be specified by a single epithelial-derived autocrine morphogen gradient. Instead, signaling by means of TGFβ1 and bone morphogenetic protein-4 (BMP4) differentially affect the rates of branching and growth of the airways. Allometric analysis revealed that development of the epithelial tree obeys power-law dynamics; TGFβ1 and BMP4 have distinct but reversible effects on the scaling coefficient of the power law. CONCLUSIONS These data suggest that although autocrine inhibition cannot specify monopodial branching, inhibitory morphogens define the dynamics of lung morphogenesis.
Collapse
Affiliation(s)
- Jason P Gleghorn
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey
| | | | | | | |
Collapse
|
17
|
Zhu L, Chen S, Chen Y. Unraveling the biological functions of Smad7 with mouse models. Cell Biosci 2011; 1:44. [PMID: 22204639 PMCID: PMC3275527 DOI: 10.1186/2045-3701-1-44] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Accepted: 12/28/2011] [Indexed: 12/22/2022] Open
Abstract
Smad7 is a key negative regulator of the transforming growth factor β (TGF-β) signaling and plays an important role in modulating a large array of biological processes. The physiological actions of Smad7 have been extensively investigated by using various mouse models. These studies have pinpointed numerous important in vivo functions of Smad7, including its activity in early embryonic development, fibrosis of many organs, skin cell differentiation, regulation of immune response and inflammation, tumorigenesis, and metabolic control. As most biological activities modulated by Smad7 are closely related to human disorders, it is anticipated that Smad7 will continue to be an intriguing molecule that will be vigorously investigated in the future to strengthen our understanding about the pathogenesis of human diseases.
Collapse
Affiliation(s)
- Lu Zhu
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.
| | | | | |
Collapse
|
18
|
Inhibition of TGF-β signaling and decreased apoptosis in IUGR-associated lung disease in rats. PLoS One 2011; 6:e26371. [PMID: 22028866 PMCID: PMC3197638 DOI: 10.1371/journal.pone.0026371] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Accepted: 09/25/2011] [Indexed: 01/04/2023] Open
Abstract
Intrauterine growth restriction is associated with impaired lung function in adulthood. It is unknown whether such impairment of lung function is linked to the transforming growth factor (TGF)-β system in the lung. Therefore, we investigated the effects of IUGR on lung function, expression of extracellular matrix (ECM) components and TGF-β signaling in rats. IUGR was induced in rats by isocaloric protein restriction during gestation. Lung function was assessed with direct plethysmography at postnatal day (P) 70. Pulmonary activity of the TGF-β system was determined at P1 and P70. TGF-β signaling was blocked in vitro using adenovirus-delivered Smad7. At P70, respiratory airway compliance was significantly impaired after IUGR. These changes were accompanied by decreased expression of TGF-β1 at P1 and P70 and a consistently dampened phosphorylation of Smad2 and Smad3. Furthermore, the mRNA expression levels of inhibitors of TGF-β signaling (Smad7 and Smurf2) were reduced, and the expression of TGF-β-regulated ECM components (e.g. collagen I) was decreased in the lungs of IUGR animals at P1; whereas elastin and tenascin N expression was significantly upregulated. In vitro inhibition of TGF-β signaling in NIH/3T3, MLE 12 and endothelial cells by adenovirus-delivered Smad7 demonstrated a direct effect on the expression of ECM components. Taken together, these data demonstrate a significant impact of IUGR on lung development and function and suggest that attenuated TGF-β signaling may contribute to the pathological processes of IUGR-associated lung disease.
Collapse
|
19
|
Abstract
Myostatin is an extracellular cytokine mostly expressed in skeletal muscles and known to play a crucial role in the negative regulation of muscle mass. Upon the binding to activin type IIB receptor, myostatin can initiate several different signalling cascades resulting in the upregulation of the atrogenes and downregulation of the important for myogenesis genes. Muscle size is regulated via a complex interplay of myostatin signalling with the insulin-like growth factor 1/phosphatidylinositol 3-kinase/Akt pathway responsible for increase in protein synthesis in muscle. Therefore, the regulation of muscle weight is a process in which myostatin plays a central role but the mechanism of its action and signalling cascades are not fully understood. Myostatin upregulation was observed in the pathogenesis of muscle wasting during cachexia associated with different diseases (i.e. cancer, heart failure, HIV). Characterisation of myostatin signalling is therefore a perspective direction in the treatment development for cachexia. The current review covers the present knowledge about myostatin signalling pathways leading to muscle wasting and the state of therapy approaches via the regulation of myostatin and/or its downstream targets in cachexia.
Collapse
|
20
|
Mosler S, Pankratz C, Seyfried A, Piechotta M, Diel P. The anabolic steroid methandienone targets the hypothalamic–pituitary–testicular axis and myostatin signaling in a rat training model. Arch Toxicol 2011; 86:109-19. [DOI: 10.1007/s00204-011-0740-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Accepted: 07/18/2011] [Indexed: 12/22/2022]
|
21
|
Leikauf GD, Concel VJ, Liu P, Bein K, Berndt A, Ganguly K, Jang AS, Brant KA, Dietsch M, Pope-Varsalona H, Dopico RA, Di YPP, Li Q, Vuga LJ, Medvedovic M, Kaminski N, You M, Prows DR. Haplotype association mapping of acute lung injury in mice implicates activin a receptor, type 1. Am J Respir Crit Care Med 2011; 183:1499-509. [PMID: 21297076 PMCID: PMC3137140 DOI: 10.1164/rccm.201006-0912oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 02/04/2011] [Indexed: 01/11/2023] Open
Abstract
RATIONALE Because acute lung injury is a sporadic disease produced by heterogeneous precipitating factors, previous genetic analyses are mainly limited to candidate gene case-control studies. OBJECTIVES To develop a genome-wide strategy in which single nucleotide polymorphism associations are assessed for functional consequences to survival during acute lung injury in mice. METHODS To identify genes associated with acute lung injury, 40 inbred strains were exposed to acrolein and haplotype association mapping, microarray, and DNA-protein binding were assessed. MEASUREMENTS AND MAIN RESULTS The mean survival time varied among mouse strains with polar strains differing approximately 2.5-fold. Associations were identified on chromosomes 1, 2, 4, 11, and 12. Seven genes (Acvr1, Cacnb4, Ccdc148, Galnt13, Rfwd2, Rpap2, and Tgfbr3) had single nucleotide polymorphism (SNP) associations within the gene. Because SNP associations may encompass "blocks" of associated variants, functional assessment was performed in 91 genes within ± 1 Mbp of each SNP association. Using 10% or greater allelic frequency and 10% or greater phenotype explained as threshold criteria, 16 genes were assessed by microarray and reverse real-time polymerase chain reaction. Microarray revealed several enriched pathways including transforming growth factor-β signaling. Transcripts for Acvr1, Arhgap15, Cacybp, Rfwd2, and Tgfbr3 differed between the strains with exposure and contained SNPs that could eliminate putative transcriptional factor recognition sites. Ccdc148, Fancl, and Tnn had sequence differences that could produce an amino acid substitution. Mycn and Mgat4a had a promoter SNP or 3'untranslated region SNPs, respectively. Several genes were related and encoded receptors (ACVR1, TGFBR3), transcription factors (MYCN, possibly CCDC148), and ubiquitin-proteasome (RFWD2, FANCL, CACYBP) proteins that can modulate cell signaling. An Acvr1 SNP eliminated a putative ELK1 binding site and diminished DNA-protein binding. CONCLUSIONS Assessment of genetic associations can be strengthened using a genetic/genomic approach. This approach identified several candidate genes, including Acvr1, associated with increased susceptibility to acute lung injury in mice.
Collapse
Affiliation(s)
- George D Leikauf
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15219-3130, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Yoshida T, Ohnuma A, Horiuchi H, Harada T. Pulmonary fibrosis in response to environmental cues and molecular targets involved in its pathogenesis. J Toxicol Pathol 2011; 24:9-24. [PMID: 22272040 PMCID: PMC3234628 DOI: 10.1293/tox.24.9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 11/25/2010] [Indexed: 12/27/2022] Open
Abstract
Chronic lung injury resulting from a variety of different causes is frequently associated with the develop ment of pulmonary fibrosis in humans. Although the etiology of pulmonary fibrosis is generally unknown, several sources of evidence support the hypothesis that a number of environmental and occupational agents play an etiologic role in the pathogenesis of this disease. The agents discussed in this review include beryllium, nylon flock, textile printing aerosols, polyvinyl chloride and didecyldimethylammonium chloride. The authors also describe a variety of animal models, including genetically modified mice, in order to investigate the molecular mechanism of pulmonary fibrosis, focusing on chemokine receptors, regulatory T cells and transforming growth factor-β and bone morphogenetic protein signaling. Overall, we propose the concept of toxicological pulmonary fibrosis as a lung disease induced in response to environmental cues.
Collapse
Affiliation(s)
- Toshinori Yoshida
- Laboratory of Pathology, Toxicology Division, The Institute
of Environmental Toxicology, 4321 Uchimoriya-machi, Joso, Ibaraki 303-0043, Japan
| | - Aya Ohnuma
- Laboratory of Pathology, Toxicology Division, The Institute
of Environmental Toxicology, 4321 Uchimoriya-machi, Joso, Ibaraki 303-0043, Japan
| | - Haruka Horiuchi
- Laboratory of Pathology, Toxicology Division, The Institute
of Environmental Toxicology, 4321 Uchimoriya-machi, Joso, Ibaraki 303-0043, Japan
| | - Takanori Harada
- The Institute of Environmental Toxicology, 4321
Uchimoriya-machi, Joso, Ibaraki 303-0043, Japan
| |
Collapse
|
23
|
Sobral LM, Montan PF, Zecchin KG, Martelli-Junior H, Vargas PA, Graner E, Coletta RD. Smad7 blocks transforming growth factor-β1-induced gingival fibroblast-myofibroblast transition via inhibitory regulation of Smad2 and connective tissue growth factor. J Periodontol 2010; 82:642-51. [PMID: 21054221 DOI: 10.1902/jop.2010.100510] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Transforming growth factor-β1 (TGF-β1), its downstream signaling mediators (Smad proteins), and specific targets, including connective tissue growth factor (CTGF), play important roles in tissue remodeling and fibrosis via myofibroblast activation. We investigated the effect of overexpression of Smad7, a TGF-β1 signaling inhibitor, on transition of gingival fibroblast to myofibroblast. Moreover, we analyzed the participation of CTGF on TGF-β1-mediated myofibroblast transformation. METHODS To study the inhibitory effect of Smad7 on TGF-β1/CTGF-mediating gingival fibroblast transition into myofibroblasts, we stably overexpressed Smad7 in normal gingival fibroblasts and in myofibroblasts from hereditary gingival fibromatosis (HGF). Myofibroblasts were characterized by the expression of the specific marker isoform α of the smooth muscle actin (α-SMA) by Western blot, flow cytometry, and immunofluorescence. Enzyme-linked immunosorbent assay for type I collagen was performed to measure myofibroblast activity. CTGF's role on myofibroblast transformation was examined by enzyme-linked immunosorbent assay and small interference RNA. RESULTS TGF-β1 induced the expression of α-SMA and CTGF, and small interference RNA-mediating CTGF silencing prevented fibroblast-myofibroblast switch induced by TGF-β1. In Smad7-overexpressing fibroblasts, ablation of TGF-β1-induced Smad2 phosphorylation marked decreased α-SMA, CTGF, and type I collagen expression. Similarly, HGF transfectants overexpressing Smad7 demonstrated low levels of α-SMA and phospho-Smad2 and significant reduction on CTGF and type I collagen production. CONCLUSIONS CTGF is critical for TGF-β1-induced gingival fibroblast-myofibroblast transition, and Smad7 overexpression is effective in the blockage of myofibroblast transformation and activation, suggesting that treatments targeting myofibroblasts by Smad7 overexpression may be clinically effective in gingival fibrotic diseases, such as HGF.
Collapse
Affiliation(s)
- Lays M Sobral
- Department of Oral Diagnosis, School of Dentistry, State University of Campinas, Piracicaba, São Paulo, Brazil
| | | | | | | | | | | | | |
Collapse
|
24
|
Aoki MS, Soares AG, Miyabara EH, Baptista IL, Moriscot AS. Expression of genes related to myostatin signaling during rat skeletal muscle longitudinal growth. Muscle Nerve 2009; 40:992-9. [DOI: 10.1002/mus.21426] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
25
|
Choi CW, Kim BI, Joung KE, Lee JA, Lee YK, Kim EK, Kim HS, Park JD, Choi JH. Decreased expression of transforming growth factor-beta1 in bronchoalveolar lavage cells of preterm infants with maternal chorioamnionitis. J Korean Med Sci 2008; 23:609-15. [PMID: 18756046 PMCID: PMC2526412 DOI: 10.3346/jkms.2008.23.4.609] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Maternal chorioamnionitis has been associated with abnormal lung development. We examined the effect of maternal chorioamnionitis on the expression of transforming growth factor-beta1 (TGF-beta1) in the lungs of preterm infants. A total of 63 preterm (<or=34 weeks) infants who were intubated in the delivery room were prospectively enrolled. Their placentas were examined for the presence of chorioamnionitis. Bronchoalveolar lavage (BAL) fluid and cells were obtained shortly after birth. TGF-beta1 was measured in BAL fluid and TGF-beta1 mRNA expression was determined by reverse transcription polymerase chain reaction (RT-PCR) in BAL cells. TGF-beta1 mRNA expression in BAL cells showed a positive correlation with gestational age (r=0.414, p=0.002). TGF-beta1 mRNA expression was significantly decreased in the presence of maternal chorioamnionitis (0.70+/-0.12 vs. 0.81+/-0.15, p=0.007). Adjustment for gestational age, birth weight, and delivery mode did not nullify the significance. TGF-beta1 mRNA expression was marginally significantly decreased in preterm infants who developed bronchopulmonary dysplasia (BPD) later (0.75+/-0.11 vs. 0.82+/-0.15, p=0.055). However, adjustment for gestational age, patent ductus arteriosus (PDA), and maternal chorioamnionitis nullified the significance. These results might be an indirect evidence that maternal chorioamnionitis may inhibit normal lung development of fetus.
Collapse
Affiliation(s)
- Chang Won Choi
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Beyong Il Kim
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Kyoung Eun Joung
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Jin-A Lee
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Yun Kyoung Lee
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Ee-Kyung Kim
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Han-Suk Kim
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - June Dong Park
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| | - Jung-Hwan Choi
- Department of Pediatrics, Seoul National University, College of Medicine, Seoul, Korea
| |
Collapse
|
26
|
Alejandre-Alcázar MA, Michiels-Corsten M, Vicencio AG, Reiss I, Ryu J, de Krijger RR, Haddad GG, Tibboel D, Seeger W, Eickelberg O, Morty RE. TGF-beta signaling is dynamically regulated during the alveolarization of rodent and human lungs. Dev Dyn 2008; 237:259-69. [PMID: 18095342 DOI: 10.1002/dvdy.21403] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Although transforming growth factor-beta (TGF-beta) signaling negatively regulates branching morphogenesis in early lung development, few studies to date have addressed the role of this family of growth factors during late lung development. We describe here that the expression, tissue localization, and activity of components of the TGF-beta signaling machinery are dynamically regulated during late lung development in the mouse and human. Pronounced changes in the expression and localization of the TGF-beta receptors Acvrl1, Tgfbr1, Tgfbr2, Tgfbr3, and endoglin, and the intracellular messengers Smad2, Smad3, Smad4, Smad6, and Smad7 were noted as mouse and human lungs progressed through the canalicular, saccular, and alveolar stages of development. TGF-beta signaling, assessed by phosphorylation of Smad2, was detected in the vascular and airway smooth muscle, as well as the alveolar and airway epithelium throughout late lung development. These data suggest that active TGF-beta signaling is required for normal late lung development.
Collapse
Affiliation(s)
- Miguel A Alejandre-Alcázar
- Department of Internal Medicine, University of Giessen Lung Center, Justus Liebig University, Giessen, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Chen H, Zhuang F, Liu YH, Xu B, Del Moral P, Deng W, Chai Y, Kolb M, Gauldie J, Warburton D, Moses HL, Shi W. TGF-beta receptor II in epithelia versus mesenchyme plays distinct roles in the developing lung. Eur Respir J 2008; 32:285-95. [PMID: 18321928 DOI: 10.1183/09031936.00165407] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Transforming growth factor (TGF)-beta signalling plays important roles in regulating lung development. However, the specific regulatory functions of TGF-beta signalling in developing lung epithelial versus mesenchymal cells are still unknown. By immunostaining, the expression pattern of the TGF-beta type II receptor (TbetaRII) was first determined in the developing mouse lung. The functions of TbetaRII in developing lung were then determined by conditionally knocking out TbetaRII in the lung epithelium of floxed-TbetaRII/surfactant protein C-reverse tetracycline transactivator/TetO-Cre mice versus mesenchyme of floxed-TbetaRII/Dermo1-Cre mice. TbetaRII was expressed only in distal airway epithelium at early gestation (embryonic day (E)11.5), but in both airway epithelium and mesenchyme from mid-gestation (E14.5) to post-natal day 14. Abrogation of TbetaRII in mouse lung epithelium resulted in retardation of post-natal lung alveolarisation, with markedly decreased type I alveolar epithelial cells, while no abnormality in prenatal lung development was observed. In contrast, blockade of TbetaRII in mesoderm-derived tissues, including lung mesenchyme, resulted in mildly abnormal lung branching and reduced cell proliferation after mid-gestation, accompanied by multiple defects in other organs, including diaphragmatic hernia. The primary lung branching defect was verified in embryonic lung explant culture. The novel findings of the present study suggest that transforming growth factor-beta type II receptor-mediated transforming growth factor-beta signalling plays distinct roles in lung epithelium versus mesenchyme to differentially control specific stages of lung development.
Collapse
Affiliation(s)
- H Chen
- Developmental Biology Program, Dept of Surgery, Childrens Hospital Los Angeles, 4650 Sunset Blvd, MS 35, Los Angeles, CA 90027, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Sun J, Chen H, Chen C, Whitsett JA, Mishina Y, Bringas P, Ma JC, Warburton D, Shi W. Prenatal lung epithelial cell-specific abrogation of Alk3-bone morphogenetic protein signaling causes neonatal respiratory distress by disrupting distal airway formation. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 172:571-82. [PMID: 18258849 DOI: 10.2353/ajpath.2008.070286] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Bone morphogenetic proteins (BMPs) play important roles in regulating lung development and function although the endogenous regulatory effects of BMP signaling are still controversial. We found that BMP type I receptor Alk3 is expressed predominantly in airway epithelial cells during development. The function of Alk3 in lung development was determined using an inducible knockout mouse model by crossing epithelial cell-specific Cre transgenic mice SPC-rtTA/TetO-Cre and floxed-Alk3 mice. Abrogation of Alk3 in mouse lung epithelia from either early lung organogenesis or late gestation resulted in similar neonatal respiratory distress phenotypes accompanied by collapsed lungs. Early-induction of Alk3 knockout in lung epithelial cells caused retardation of early lung branching morphogenesis, reduced cell proliferation, and differentiation. However, late gestation induction of the knockout caused changes in cell proliferation and survival, as shown by altered cell biology, reduced expression of peripheral epithelial markers (Clara cell-specific protein, surfactant protein C, and aquaporin-5), and lack of surfactant secretion. Furthermore, canonical Wnt signaling was perturbed, possibly through reduced Wnt inhibitory factor-1 expression in Alk3-knockout lungs. Therefore, our data suggest that deficiency of appropriate BMP signaling in lung epithelial cells results in prenatal lung malformation, neonatal atelectasis, and respiratory failure.
Collapse
Affiliation(s)
- Jianping Sun
- Developmental Biology Program, Childrens Hospital Los Angeles, 4650 Sunset Blvd., MS 35, Los Angeles, CA 90027, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Kinane TB. Lung development and implications for hypoplasia found in congenital diaphragmatic hernia. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2007; 145C:117-24. [PMID: 17436303 DOI: 10.1002/ajmg.c.30124] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Congenital diaphragmatic hernia (CDH) is associated with various degrees of pulmonary hypoplasia and severe persistent pulmonary hypertension in the newborn. These conditions have significant implications for the outcome for the patient. Defects in early lung development are likely to be central to the generation of hypoplasia. A number of mouse models with defects in pathways that are central to lung development were found to have CDH. Understanding all aspects of early lung development will provide fresh insight into the pathogenesis of CDH and its associated conditions.
Collapse
Affiliation(s)
- T Bernard Kinane
- Pediatric Pulmonary, Massachusetts General Hospital for Children, Boston, MA 02114, USA.
| |
Collapse
|
30
|
Wang B, Omar A, Angelovska T, Drobic V, Rattan SG, Jones SC, Dixon IMC. Regulation of collagen synthesis by inhibitory Smad7 in cardiac myofibroblasts. Am J Physiol Heart Circ Physiol 2007; 293:H1282-90. [PMID: 17513491 DOI: 10.1152/ajpheart.00910.2006] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Transforming growth factor-beta(1) (TGF-beta(1)) signal and downstream Smads play an important role in tissue fibrosis and matrix remodeling in various etiologies of heart failure. Inhibitory Smad7 (I-Smad7) is an inducible regulatory Smad protein that antagonizes TGF-beta(1) signal mediated via direct abrogation of R-Smad phosphorylation. The effect of ectopic I-Smad7 on net collagen production was investigated using hydroxyproline assay. Adenovirus-mediated I-Smad7 gene (at 100 multiplicity of infection) transfer was associated with significant decrease of collagen synthesis in the presence and absence of TGF-beta(1) in primary rat cardiac myofibroblasts. In I-Smad7-infected cells, we also observed the ablation of TGF-beta(1)-induced R-Smad2 phosphorylation vs. LacZ controls. Overdriven I-Smad7 was associated with significantly increased expression of immunoreactive 65-kDa matrix metalloproteinase-2 (MMP-2) protein in culture medium of myofibroblast compared with LacZ-infected cells. Expression of the 72-kDa MMP-2 variant, e.g., the inactive form, was not altered by exogenous I-Smad7 transfection/overexpression. Furthermore, I-Smad7 overexpression was associated with a significant increase and decrease in expression of p27 and phospho-Rb protein, respectively, as well as reduced [(3)H]thymidine incorporation vs. Ad-LacZ-infected controls. We suggest that negative modulation of R-Smad phosphorylation by ectopic I-Smad7 may contribute to the downregulation of collagen in cardiac myofibroblasts and may suppress the proliferation of these cells. Thus treatments targeting the collagen deposition by overexpression of I-Smad7 may provide a new therapeutic strategy for cardiac fibrosis.
Collapse
Affiliation(s)
- Baiqiu Wang
- Institute of Cardiovascular Science, St. Boniface General Hospital Research Centre and Department of Physiology, University of Manitoba, Winnipeg, Canada
| | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
The vertebrate lung consists of multiple cell types that are derived primarily from endodermal and mesodermal compartments of the early embryo. The process of pulmonary organogenesis requires the generation of precise signaling centers that are linked to transcriptional programs that, in turn, regulate cell numbers, differentiation, and behavior, as branching morphogenesis and alveolarization proceed. This review summarizes knowledge regarding the expression and proposed roles of transcription factors influencing lung formation and function with particular focus on knowledge derived from the study of the mouse. A group of transcription factors active in the endodermally derived cells of the developing lung tubules, including thyroid transcription factor-1 (TTF-1), beta-catenin, Forkhead orthologs (FOX), GATA, SOX, and ETS family members are required for normal lung morphogenesis and function. In contrast, a group of distinct proteins, including FOXF1, POD1, GLI, and HOX family members, play important roles in the developing lung mesenchyme, from which pulmonary vessels and bronchial smooth muscle develop. Lung formation is dependent on reciprocal signaling among cells of both endodermal and mesenchymal compartments that instruct transcriptional processes mediating lung formation and adaptation to breathing after birth.
Collapse
Affiliation(s)
- Yutaka Maeda
- Division of Pulmonary Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center and The University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | | | | |
Collapse
|
32
|
Licona-Limón P, Soldevila G. The role of TGF-beta superfamily during T cell development: new insights. Immunol Lett 2007; 109:1-12. [PMID: 17287030 DOI: 10.1016/j.imlet.2006.12.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Revised: 12/21/2006] [Accepted: 12/23/2006] [Indexed: 10/23/2022]
Abstract
Members of the transforming growth factor beta (TGF-beta) superfamily are soluble factors that regulate a variety of functional responses including proliferation, differentiation, apoptosis and cell cycle, among others, depending not only on the cell type and its differentiation state, but also on the milieu of cytokines present. All three members of this superfamily: TGF-betas, bone morphogenetic proteins (BMPs) and Activins, have been shown to be expressed in the thymus suggesting their potential role as regulators of the T lymphocyte differentiation process. Although initial reports described the role of TGF-beta in controlling specific checkpoints during thymocyte development, recent data has provided new evidence on the role of BMPs and Activins in this process. This review provides new insights on the function of members of the TGF-beta superfamily at different stages of thymocyte development.
Collapse
Affiliation(s)
- P Licona-Limón
- Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Escolar s/n, México DF-04510, Mexico
| | | |
Collapse
|
33
|
Kopp J, Seyhan H, Müller B, Lanczak J, Pausch E, Gressner AM, Dooley S, Horch RE. N-acetyl-L-cysteine abrogates fibrogenic properties of fibroblasts isolated from Dupuytren's disease by blunting TGF-beta signalling. J Cell Mol Med 2006; 10:157-65. [PMID: 16563228 PMCID: PMC3933108 DOI: 10.1111/j.1582-4934.2006.tb00297.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Dupuytren's disease, a benign fibroproliferative disorder of the palmar fascia, represents an ideal model to study tissue fibrosis. Transforming growth factor-β1 (TGF-β1) and its downstream Smad signalling system is well established as a key player during fibrogenesis. Thus, targeting this basic pathomechanism seems suitable to establish new treatment strategies. One such promising treatment involves the substance N-acetyl-L-cysteine (NAC), shown to have antifibrotic properties in hepatic stellate cells and rat fibroblasts. In order to investigate antifibrotic effects of N-acetyl-L-cysteine (NAC), fibroblasts were isolated from surgically resected fibrotic palmar tissues (Dupuytren fibroblasts, DF) and exposed to different concentrations of NAC and recombinant TGF-β1. Fibroblasts isolated from tendon pulleys served as controls (control fibroblasts, CF). Smad signalling was investigated by a Smad binding element driven reporter gene analysis. Both cell types express TGF-β1, indicating autocrine signalling in DF and CF. This was confirmed by comparing reporter gene activity from LacZ and Smad7 adenovirus infected cells. NAC treatment resulted in abrogation of Smad mediated signalling comparable to ectopically overexpressed Smad7, even when the cells were stimulated with recombinant TGF-β1 or ectopically expressed a constitutively active TGF-β receptor type I. Additionally, NAC dose-dependently decreased expression of three major indicators of impaired fibrotic matrix turnover, namely alpha-smooth muscle actin (α-SMA), α 1 type I procollagen (CollA1), and plasminogen activator inhibitor-type I (PAI-1). Our results suggest that TGF-β signalling and subsequent expression of fibrogenesis related proteins in Dupuytren's disease is abrogated by NAC thus providing a basis for a therapeutic strategy in Dupuytren's disease and other fibroproliferative disorders.
Collapse
Affiliation(s)
- Jürgen Kopp
- Department of Plastic and Hand Surgery, University Medical Center, Erlangen, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
Hepatic fibrosis is the common wound-healing response to chronic liver injury. In this process, activation of hepatic stellate cells is characteristic of cell proliferation and migration, production of collagen and other extracellular matrix (ECM) molecules, and contraction after transforming into myofibroblasts. It has been shown that the fibrogenic process is prominently regulated by transforming growth factor-beta1 (TGF-beta1) and that the specific blockade of TGF-beta1/Smad3 signaling may therapeutically intervene the fibrosis of various tissues. In this review, we attempt to integrate recent advances in the understanding of the mechanisms underlying TGF-beta1/Smad3 pathway modulation of ECM gene expression in the context of liver fibrosis, discuss intervention strategies targeting the blockade of related signal pathways, and look into novel ways to the safe and efficacious prevention and treatment of hepatic fibrosis.
Collapse
Affiliation(s)
- Xingjun Liu
- Protein & Peptide Pharmaceutical Laboratory, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | | | | |
Collapse
|
35
|
Abstract
Organized and coordinated lung development follows transcriptional regulation of a complex set of cell-cell and cell-matrix interactions resulting in a blood-gas interface ready for physiologic gas exchange at birth. Transcription factors, growth factors, and various other signaling molecules regulate epithelial-mesenchymal interactions by paracrine and autocrine mechanisms. Transcriptional control at the earliest stages of lung development results in cell differentiation and cell commitment in the primitive lung bud, in essence setting up a framework for pattern formation and branching morphogenesis. Branching morphogenesis results in the formation of the conductive airway system, which is critical for alveolization. Lung development is influenced at all stages by spatial and temporal distribution of various signaling molecules and their receptors and also by the positive and negative control of signaling by paracrine, autocrine, and endocrine mechanisms. Lung bud formation, cell differentiation, and its interaction with the splanchnic mesoderm are regulated by HNF-3beta, Shh, Nkx2.1, HNF-3/Forkhead homolog-8 (HFH-8), Gli, and GATA transcription factors. HNF-3beta regulates Nkx2.1, a transcription factor critical to the formation of distal pulmonary structures. Nkx2.1 regulates surfactant protein genes that are important for the development of alveolar stability at birth. Shh, produced by the foregut endoderm, regulates lung morphogenesis signaling through Gli genes expressed in the mesenchyme. FGF10, produced by the mesoderm, regulates branching morphogenesis via its receptors on the lung epithelium. Alveolization and formation of the capillary network are influenced by various factors that include PDGF, vascular endothelial growth factor (VEGF), and retinoic acid. Epithelial-endothelial interactions during lung development are important in establishing a functional blood-gas interface. The effects of various growth factors on lung development have been demonstrated by gain- or loss-of-function studies in null mutant and transgenic mice models. Understanding the role of growth factors and various other signaling molecules and their cellular interactions in lung development will provide us with new insights into the pathogenesis of bronchopulmonary dysplasia and disorders of lung morphogenesis.
Collapse
Affiliation(s)
- Vasanth H Kumar
- Department of Pediatrics (Neonatology), State University of New York, The Women & Children's Hospital of Buffalo, Buffalo, New York, USA
| | | | | | | | | |
Collapse
|
36
|
Zhu X, Topouzis S, Liang LF, Stotish RL. Myostatin signaling through Smad2, Smad3 and Smad4 is regulated by the inhibitory Smad7 by a negative feedback mechanism. Cytokine 2005; 26:262-72. [PMID: 15183844 DOI: 10.1016/j.cyto.2004.03.007] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Revised: 02/16/2004] [Accepted: 03/15/2004] [Indexed: 01/03/2023]
Abstract
As a member of the TGF-beta superfamily, myostatin is a specific negative regulator of skeletal muscle mass. To identify the downstream components in the myostatin signal transduction pathway, we used a luciferase reporter assay to elucidate myostatin-induced activity. The myostatin-induced transcription requires the participation of regulatory Smads (Smad2/3) and Co-Smads (Smad4). Conversely, inhibitory Smad7, but not Smad6, dramatically reduces the myostatin-induced transcription. This Smad7 inhibition is enhanced by co-expression of Smurf1. We have also shown that Smad7 expression is stimulated by myostatin via the interaction between Smad2, Smad3, Smad4 and the SBE (Smad binding element) in the Smad7 promoter. These results suggest that the myostatin signal transduction pathway is regulated by Smad7 through a negative feedback mechanism.
Collapse
Affiliation(s)
- Xiangyang Zhu
- MetaMorphix Inc., 8510A Corridor Road, Savage, MD 20763, USA.
| | | | | | | |
Collapse
|
37
|
Roth-Kleiner M, Post M. Similarities and dissimilarities of branching and septation during lung development. Pediatr Pulmonol 2005; 40:113-34. [PMID: 15965895 DOI: 10.1002/ppul.20252] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The lungs of small premature babies are at a developmental stage of finalizing their airway tree by a process called branching morphogenesis, and of creating terminal gas exchange units by a mechanism called septation. If the branching process is disturbed, the lung has a propensity to be hypoplastic. If septation is impaired, the terminal gas exchange units, the alveoli, tend to be enlarged and reduced in number, an entity known as bronchopulmonary dysplasia. Here, we review current knowledge of key molecules influencing branching and septation. In particular, we discuss the molecular similarities and dissimilarities between the two processes of airspace enlargement. Understanding of the molecular mechanisms regulating branching and septation may provide perinatologists with targets for improving lung growth and maturation.
Collapse
Affiliation(s)
- Matthias Roth-Kleiner
- Lung Biology Program, Hospital for Sick Children Research Institute, and Department of Laboratory Medicine, University of Toronto, Toronto, Ontario, Canada
| | | |
Collapse
|
38
|
Sebestyén A, Barna G, Nagy K, Jánosi J, Paku S, Kohut E, Berczi L, Mihalik R, Kopper L. Smad signal and TGFβ induced apoptosis in human lymphoma cells. Cytokine 2005; 30:228-35. [PMID: 15927846 DOI: 10.1016/j.cyto.2005.01.013] [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] [Received: 02/23/2004] [Revised: 10/26/2004] [Accepted: 01/25/2005] [Indexed: 11/17/2022]
Abstract
Transforming growth factor beta1 (TGF beta1) has antiproliferative and/or apoptotic effect on lymphoid cells. In certain lymphomas exogenous TGF beta1 is able to induce apoptosis, however many lymphoid malignancies are resistant to the endogenous TGF beta1 production. We studied the expression and the activity of TGF beta1 signalling components in B cell lymphoma cell lines (e.g. HT 58 cells) and in isolated human peripheral mononuclear cells (PBMCs) from healthy individual's and B-CLL patient's blood. We found that all signal transducer Smads (Smad2,-3; Smad4) and at least one of the inhibitory Smads (Smad6,-7) were expressed in non-treated lymphoma cells, but the inhibitory Smads did not in normal/control PBMCs. However, after TGF beta1 treatment Smad6 disappeared, while the expression of Smad7 increased in HT 58 cells. The activity of Smad signals was proved by phosphorylation of Smad2, nuclear translocation of Smad2/3, and the increased expression of Smad-dependent gene, TIEG in TGF beta1 treated lymphoma cells. These results showed that Smad signaling is available in certain different human lymphoma cells, however ISmads expression could inhibit the signal transmission. This findings indicates that the lost sensitivity of lymphoma cells toward a physiological regulatory factor could be reversed.
Collapse
Affiliation(s)
- Anna Sebestyén
- Ist Department of Pathology and Experimental Cancer Research, Faculty of Medicine, Semmelweis University, 1085 Budapest, Hungary.
| | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Warburton D, Bellusci S, De Langhe S, Del Moral PM, Fleury V, Mailleux A, Tefft D, Unbekandt M, Wang K, Shi W. Molecular mechanisms of early lung specification and branching morphogenesis. Pediatr Res 2005; 57:26R-37R. [PMID: 15817505 DOI: 10.1203/01.pdr.0000159570.01327.ed] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The "hard wiring" encoded within the genome that determines the emergence of the laryngotracheal groove and subsequently early lung branching morphogenesis is mediated by finely regulated, interactive growth factor signaling mechanisms that determine the automaticity of branching, interbranch length, stereotypy of branching, left-right asymmetry, and finally gas diffusion surface area. The extracellular matrix is an important regulator as well as a target for growth factor signaling in lung branching morphogenesis and alveolarization. Coordination not only of epithelial but also endothelial branching morphogenesis determines bronchial branching and the eventual alveolar-capillary interface. Improved prospects for lung protection, repair, regeneration, and engineering will depend on more detailed understanding of these processes. Herein, we concisely review the functionally integrated morphogenetic signaling network comprising the critical bone morphogenetic protein, fibroblast growth factor, Sonic hedgehog, transforming growth factor-beta, vascular endothelial growth factor, and Wnt signaling pathways that specify and drive early embryonic lung morphogenesis.
Collapse
Affiliation(s)
- David Warburton
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, CA 90027, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Chen H, Sun J, Buckley S, Chen C, Warburton D, Wang XF, Shi W. Abnormal mouse lung alveolarization caused by Smad3 deficiency is a developmental antecedent of centrilobular emphysema. Am J Physiol Lung Cell Mol Physiol 2005; 288:L683-91. [PMID: 15591413 DOI: 10.1152/ajplung.00298.2004] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Transforming growth factor-β (TGF-β) signaling plays an important regulatory role during lung development and remodeling. Smad3 is a major downstream signal transducer in the TGF-β pathway from the cell membrane to the nucleus. In Smad3 null mutant mice, we have observed retarded lung alveolarization from postnatal day 7 to day 28, and subsequently centrilobular emphysema starting from day 28, as determined by morphometric analysis. In addition to the morphological changes, peripheral lung cell proliferation in Smad3 knockout mice was reduced compared with the wild-type control between postnatal days 7 and 28. Expression of tropoelastin at the mRNA level was also dramatically decreased in Smad3 knockout lungs from postnatal day 28 through adulthood. Furthermore, increased matrix metalloproteinase-9 protein expression and activity were detected in the Smad3 knockout mouse lung tissue and the bronchoalveolar lavage fluid at postnatal day 28 when the centrilobular emphysema pathology was just beginning to appear. Therefore, these results indicate that Smad3 not only has a positive regulatory impact on neonatal lung alveolarization but also potentially plays a protective role against the occurrence of centrilobular emphysema later on in life.
Collapse
Affiliation(s)
- Hui Chen
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA, USA
| | | | | | | | | | | | | |
Collapse
|
41
|
Wang W, Huang XR, Li AG, Liu F, Li JH, Truong LD, Wang XJ, Lan HY. Signaling mechanism of TGF-beta1 in prevention of renal inflammation: role of Smad7. J Am Soc Nephrol 2005; 16:1371-83. [PMID: 15788474 DOI: 10.1681/asn.2004121070] [Citation(s) in RCA: 204] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
TGF-beta has been shown to play a critical role in anti-inflammation; however, the signaling mechanisms of TGF-beta in anti-inflammatory response remains largely unclear. This study reported that mice that overexpress latent TGF-beta1 on skin are protected against renal inflammation in a model of obstructive kidney disease and investigated the signaling mechanism of TGF-beta1 in inhibition of renal inflammation in vivo and in vitro. Seven days after urinary obstruction, wild-type mice developed severe renal inflammation, including massive T cell and macrophage infiltration and marked upregulation of IL-1beta, TNF-alpha, and intercellular adhesion molecule-1 (all P < 0.001). Surprising, renal inflammation was prevented in transgenic mice. This was associated with an increase in latent TGF-beta1 in circulation (a 10-fold increase) and renal tissues (a 2.5-fold increase). Further studies showed that inhibition of renal inflammation in TGF-beta1 transgenic mice was also associated with a marked upregulation of renal Smad7 and IkappaBalpha and a suppression of NF-kappaB activation in the diseased kidney (all P < 0.01). These in vivo findings suggested the importance of TGF-beta-NF-kappaB cross-talk signaling pathway in regulating renal inflammation. This was tested in vitro in a doxycycline-regulated Smad7-expressing renal tubular cell line. Overexpression of Smad7 was able to upregulate IkappaBalpha directly in a time- and dose-dependent manner, thereby inhibiting NF-kappaB activation and NF-kappaB-driven inflammatory response. In conclusion, latent TGF-beta may have protective roles in renal inflammation. Smad7-mediated inhibition of NF-kappaB activation via the induction of IkBalpha may be the central mechanism by which latent TGF-beta prevents renal inflammation.
Collapse
Affiliation(s)
- Wansheng Wang
- Department of Medicine, Baylor College of Medicine, One Baylor Plaza, Alkek N520, Houston, Texas 77030, USA
| | | | | | | | | | | | | | | |
Collapse
|
42
|
König HG, Kögel D, Rami A, Prehn JHM. TGF-{beta}1 activates two distinct type I receptors in neurons: implications for neuronal NF-{kappa}B signaling. ACTA ACUST UNITED AC 2005; 168:1077-86. [PMID: 15781474 PMCID: PMC2171851 DOI: 10.1083/jcb.200407027] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Transforming growth factor-βs (TGF-βs) are pleiotropic cytokines involved in development and maintenance of the nervous system. In several neural lesion paradigms, TGF-β1 exerts potent neuroprotective effects. Neurons treated with TGF-β1 activated the canonical TGF-β receptor I/activin-like kinase receptor 5 (ALK5) pathway. The transcription factor nuclear factor-κB (NF-κB) plays a fundamental role in neuroprotection. Treatment with TGF-β1 enhanced NF-κB activity in gelshift and reporter gene analyses. However, ectopic expression of a constitutively active ALK5 failed to mimic these effects. ALK1 has been described as an alternative TGF-β receptor in endothelial cells. Interestingly, we detected significant basal expression of ALK1 and its injury-induced up-regulation in neurons. Treatment with TGF-β1 also induced a pronounced increase in downstream Smad1 phosphorylation. Overexpression of a constitutively active ALK1 mimicked the effect of TGF-β1 on NF-κB activation and neuroprotection. Our data suggest that TGF-β1 simultaneously activates two distinct receptor pathways in neurons and that the ALK1 pathway mediates TGF-β1–induced NF-κB survival signaling.
Collapse
Affiliation(s)
- Hans-Georg König
- Experimental Neurosurgery, Center for Neurology and Neurosurgery, Johann Wolfgang Goethe-University Clinics, D-60590 Frankfurt, Germany
| | | | | | | |
Collapse
|
43
|
Chen C, Chen H, Sun J, Bringas P, Chen Y, Warburton D, Shi W. Smad1 expression and function during mouse embryonic lung branching morphogenesis. Am J Physiol Lung Cell Mol Physiol 2005; 288:L1033-9. [PMID: 15681399 DOI: 10.1152/ajplung.00277.2004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Bone morphogenetic protein (BMP) 4 plays very important roles in regulating developmental processes of many organs, including lung. Smad1 is one of the BMP receptor downstream signaling proteins that transduce BMP4 ligand signaling from cell surface to nucleus. The dynamic expression patterns of Smad1 in embryonic mouse lungs were examined using immunohistochemistry. Smad1 protein was predominantly detected in peripheral airway epithelial cells of early embryonic lung tissue [embryonic day 12.5 (E12.5)], whereas Smad1 protein expression in mesenchymal cells increased during mid-late gestation. Many Smad1-positive mesenchymal cells were localized adjacent to large airway epithelial cells and endothelial cells of blood vessels, which colocalized with a molecular marker of smooth muscle cells (alpha-smooth muscle actin). The biological function of Smad1 in early lung branching morphogenesis was then studied in our established E11.5 lung explant culture model. Reduction of endogenous Smad1 expression was achieved by adding a Smad1-specific antisense DNA oligonucleotide, causing approximately 20% reduction of lung epithelial branching. Furthermore, airway epithelial cell proliferation and differentiation were also inhibited when endogenous Smad1 expression was knocked down. Therefore, these data indicate that Smad1, acting as an intracellular BMP signaling pathway component, positively regulates early mouse embryonic lung branching morphogenesis.
Collapse
Affiliation(s)
- Cheng Chen
- Developmental Biology Program, The Saban Research Institute of Childrens Hospital Los Angeles, 4650 Sunset Blvd., MS 35, Los Angeles, CA 90027, USA
| | | | | | | | | | | | | |
Collapse
|
44
|
Kanamaru Y, Nakao A, Tanaka Y, Inagaki Y, Ushio H, Shirato I, Horikoshi S, Okumura K, Ogawa H, Tomino Y. Involvement of p300 in TGF-β/Smad-Pathway-Mediated α2(I) Collagen Expression in Mouse Mesangial Cells. ACTA ACUST UNITED AC 2004; 95:e36-42. [PMID: 14520013 DOI: 10.1159/000073022] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2002] [Accepted: 07/11/2003] [Indexed: 11/19/2022]
Abstract
BACKGROUND Transforming growth factor beta 1 (TGF-beta1) induces alpha2(I) collagen gene (COL1A2) expression in mesangial cells through physical and functional cooperation of Smad proteins and Sp1. A transcriptional coactivator, p300, is also suggested to play an important role in TGF-beta1/Smad signal transduction. However, the role of p300 in TGF-beta1/Smad-pathway-mediated transcriptional activation of the COL1A2 gene in mesangial cells is still obscure. METHODS Endogenous p300 expression and its modulation by TGF-beta1 were evaluated by Western blotting and immunofluorescence. The physical interaction of p300 with Smad2/3 was examined by immunoprecipitation followed by Western blotting. The functional role of p300 in TGF-beta1/Smad-pathway-mediated COL1A2 transcription was investigated in cotransfection experiments using a COL1A2 promoter-luciferase reporter gene construct and p300 expression plasmids. RESULTS TGF-beta1 induced COL1A2 gene expression in cultured mouse mesangial cells which was blocked by overexpression of inhibitory Smad7. In addition, TGF-beta1-induced nuclear export of endogenous Smad7 was observed in mouse mesangial cells. Endogenous p300 was expressed in the nucleus of the cells. TGF-beta1 induced interaction of endogenous p300 with Smad2/3, and a dominant negative construct of p300 inhibited the TGF-beta1-induced COL1A2 expression in cultured mouse mesangial cells. CONCLUSIONS p300 may be involved in TGF-beta1/Smad-pathway-mediated type I collagen gene transcription in mouse mesangial cells. Our findings would reveal a molecular basis of TGF-beta1-induced type I collagen gene transcription in mouse mesangial cells.
Collapse
Affiliation(s)
- Yutaka Kanamaru
- Division of Nephrology, Department of Internal Medicine, Juntendo University School of Medicine, Tokyo, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Mochizuki T, Miyazaki H, Hara T, Furuya T, Imamura T, Watabe T, Miyazono K. Roles for the MH2 Domain of Smad7 in the Specific Inhibition of Transforming Growth Factor-β Superfamily Signaling. J Biol Chem 2004; 279:31568-74. [PMID: 15148321 DOI: 10.1074/jbc.m313977200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Signals by cytokines of the transforming growth factor-beta (TGF-beta) superfamily are negatively regulated by inhibitory Smads (I-Smads). Smad7 inhibits signaling by both TGF-beta and bone morphogenetic proteins (BMPs), whereas Smad6 inhibits TGF-beta signals less effectively. I-Smads have amino-terminal N domains and carboxyl-terminal Mad homology 2 (MH2) domains. The N domains are essential for specific inhibition of TGF-beta signaling by Smad7, whereas the MH2 domains of I-Smads are involved in the inhibition of TGF-beta superfamily signals through interaction with type I receptors. Here, we have identified four basic amino acid residues (Lys-312, Lys-316, Lys-401, and Arg-409) in the basic surface of the Smad7 MH2 domain that play important roles in interaction with type I receptors. Mutations of the four basic amino acid residues to acidic residues (K312E, K316E, K401E, and R409E) abolished the interaction of Smad7 with TGF-beta type I receptors, inhibition of Smad2 phosphorylation and transcriptional responses induced by TGF-beta, and induction of target genes of endogenous activin/Nodal signals in Xenopus early embryos. The K401E and R409E mutants of Smad7 were also unable to interact with BMP type I receptors (BMPR-I), repress the Smad5 phosphorylation and transcription induced by BMP, and effectively inhibit endogenous BMP signals in Xenopus early embryos. However, the K312E and K316E mutants were able to interact with BMPR-I and retained the ability to inhibit BMP signaling. Thus, the MH2 domain of Smad7 plays important roles in specific inhibition of TGF-beta superfamily signals through differential interaction with type I receptors.
Collapse
Affiliation(s)
- Toshiaki Mochizuki
- Department of Biochemistry, Cancer Institute of the Japanese Foundation for Cancer Research (JFCR), Tokyo 170-8455, Japan
| | | | | | | | | | | | | |
Collapse
|
46
|
Shi W, Chen H, Sun J, Chen C, Zhao J, Wang YL, Anderson KD, Warburton D. Overexpression of Smurf1 negatively regulates mouse embryonic lung branching morphogenesis by specifically reducing Smad1 and Smad5 proteins. Am J Physiol Lung Cell Mol Physiol 2004; 286:L293-300. [PMID: 14711801 DOI: 10.1152/ajplung.00228.2003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Early embryonic lung branching morphogenesis is regulated by many growth factor-mediated pathways. Bone morphogenetic protein 4 (BMP4) is one of the morphogens that stimulate epithelial branching in mouse embryonic lung explant culture. To further understand the molecular mechanisms of BMP4-regulated lung development, we studied the biological role of Smad-ubiquitin regulatory factor 1 (Smurf1), an ubiquitin ligase specific for BMP receptor-regulated Smads, during mouse lung development. The temporo-spatial expression pattern of Smurf1 in mouse embryonic lung was first determined by quantitative real-time PCR and immunohistochemistry. Overexpression of Smurf1 in airway epithelial cells by intratracheal introduction of recombinant adenoviral vector dramatically inhibited embryonic day (E) 11.5 lung explant growth in vitro. This inhibition of lung epithelial branching was restored by coexpression of Smad1 or by addition of soluble BMP4 ligand into the culture medium. Studies at the cellular level show that overexpression of Smurf1 reduced epithelial cell proliferation and differentiation, as documented by reduced PCNA-positive cell index and by reduced mRNA levels for surfactant protein C and Clara cell protein 10 expression. Further studies found that overexpression of Smurf1 reduced BMP-specific Smad1 and Smad5, but not Smad8, protein levels. Thus overexpression of Smurf1 specifically promotes Smad1 and Smad5 ubiquitination and degradation in embryonic lung epithelium, thereby modulating the effects of BMP4 on embryonic lung growth.
Collapse
Affiliation(s)
- Wei Shi
- Developmental Biology Program, Department of Surgery, Children's Hospital Los Angeles, 4650 Sunset Blvd., MS 35, Los Angeles, CA 90027, USA.
| | | | | | | | | | | | | | | |
Collapse
|
47
|
Lin X, Liang YY, Sun B, Liang M, Shi Y, Brunicardi FC, Shi Y, Feng XH. Smad6 recruits transcription corepressor CtBP to repress bone morphogenetic protein-induced transcription. Mol Cell Biol 2004; 23:9081-93. [PMID: 14645520 PMCID: PMC309600 DOI: 10.1128/mcb.23.24.9081-9093.2003] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Smad6 and Smad7 are inhibitory Smads induced by transforming growth factor beta-Smad signal transduction pathways in a negative-feedback mechanism. Previously it has been thought that inhibitory Smads bind to the type I receptor and block the phosphorylation of receptor-activated Smads, thereby inhibiting the initiation of Smad signaling. Conversely, few studies have suggested the possible nuclear functions of inhibitory Smads. Here, we present compelling evidence demonstrating that Smad6 repressed bone morphogenetic protein-induced Id1 transcription through recruiting transcriptional corepressor C-terminal binding protein (CtBP). A consensus CtBP-binding motif, PLDLS, was identified in the linker region of Smad6. Our findings show that mutation in the motif abolished the Smad6 binding to CtBP and subsequently its repressor activity of transcription. We conclude that the nuclear functions and physical interaction of Smad6 and CtBP provide a novel mechanism for the transcriptional regulation by inhibitory Smads.
Collapse
Affiliation(s)
- Xia Lin
- Michael E. DeBakey Department of Surgery, Baylor College of Medicine, One Baylor Plaza, Room 131D, Houston, TX 77030, USA.
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Li JH, Huang XR, Zhu HJ, Oldfield M, Cooper M, Truong LD, Johnson RJ, Lan HY. Advanced glycation end products activate Smad signaling via TGF-beta-dependent and independent mechanisms: implications for diabetic renal and vascular disease. FASEB J 2004; 18:176-8. [PMID: 12709399 DOI: 10.1096/fj.02-1117fje] [Citation(s) in RCA: 196] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
While it is thought that advanced glycation end products (AGEs) act by stimulating transforming growth factor (TGF)-beta to mediate diabetic injury, we report that AGEs can activate TGF-beta signaling, Smads, and mediate diabetic scarring directly and independently of TGF-beta. AGEs activate Smad2/3 in renal and vascular cells at 5 min, peaking over 15-30 min before TGF-beta synthesis at 24 h and occurs in TGF-beta receptor I and II mutant cells. This is mediated by RAGE and ERK/p38 mitogen-activated protein kinases (MAPKs). In addition, AGEs also activate Smads at 24 h via the classic TGF-beta-dependent pathway. A substantial inhibition of AGE-induced Smad activation and collagen synthesis by ERK/p38 MAPK inhibitors, but not by TGF-beta blockade, suggests that the MAPK-Smad signaling crosstalk pathway is a key mechanism in diabetic scarring. Prevention of AGE-induced Smad activation and collagen synthesis by overexpression of Smad7 indicates that Smad signaling may play a critical role in diabetic complications. This is further supported by the findings that activation of Smad2/3 in human diabetic nephropathy and vasculopathy is associated with local deposition of AGEs and up-regulation of RAGE. Thus, AGEs act by activating Smad signaling to mediate diabetic complications via both TGF-beta-dependent and -independent pathways, shedding new light on the pathogenesis of diabetic organ injury.
Collapse
Affiliation(s)
- Jin H Li
- Department of Medicine-Nephrology, Baylor College of Medicine, Houston, Texas 77030, USA
| | | | | | | | | | | | | | | |
Collapse
|
49
|
Scharstuhl A, Diepens R, Lensen J, Vitters E, van Beuningen H, van der Kraan P, van den Berg W. Adenoviral overexpression of Smad-7 and Smad-6 differentially regulates TGF-beta-mediated chondrocyte proliferation and proteoglycan synthesis. Osteoarthritis Cartilage 2003; 11:773-82. [PMID: 14609530 DOI: 10.1016/s1063-4584(03)00165-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess if various biological responses to transforming growth factor-beta (TGF-beta) in chondrocytes are differentially regulated by Smad-6 and Smad-7. DESIGN Adenoviral overexpression of Smad-6 or -7 mRNA in a chondrocyte cell line was determined via semi-quantitative RT-PCR and protein overexpression was studied by immunocytochemistry. Furthermore, the effect of Smad-6 and -7 overexpression on TGF-beta-induced PAI-1 and aggrecan mRNA upregulation was studied via quantitative RT-PCR. The effect of Smad-6 and -7 overexpression on TGF-beta-induced chondrocyte proliferation was studied via DNA quantification, whereas TGF-beta-induced proteoglycan (PG) synthesis was studied by 35S-sulfate incorporation. RESULTS Adenoviral transfection of chondrocytes with Smad-6 and -7 resulted in strong upregulation of Smad-6 and -7 mRNA levels, respectively. Immunocytochemistry showed overexpression of Smad-6 and -7 proteins in both the nucleus and cytoplasm. Smad-6 overexpression significantly inhibited TGF-beta-stimulated chondrocyte proliferation, although proliferation was not completely abolished. Smad-7 overexpression, however, completely antagonized the TGF-beta effect on proliferation. Smad-6 overexpression had no effect on TGF-beta-induced PAI-1 expression, while overexpression of Smad-7 completely blocked this TGF-beta effect. Additionally, overexpression of Smad-7, but not Smad-6, totally prevented TGF-beta-induced PG synthesis on the mRNA and protein levels. CONCLUSIONS Adenoviral transfection of chondrocytes with Smad-6 and -7 resulted in strong upregulation of Smad-6 and -7 mRNA and protein levels. Furthermore, overexpression of Smad-7 in chondrocytes totally inhibited important TGF-beta-mediated biological responses such as proliferation and PG synthesis, while overexpressed Smad-6 had no or only a partial inhibitory effect on TGF-beta activity. We conclude that in chondrocytes distinct TGF-beta activities are differentially regulated by Smad-6 and Smad-7.
Collapse
Affiliation(s)
- A Scharstuhl
- Experimental Rheumatology and Advanced Therapeutics, University Medical Center Nijmegen, Nijmegen, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
50
|
Shi W, Chen H, Sun J, Buckley S, Zhao J, Anderson KD, Williams RG, Warburton D. TACE is required for fetal murine cardiac development and modeling. Dev Biol 2003; 261:371-80. [PMID: 14499647 DOI: 10.1016/s0012-1606(03)00315-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Tumor necrosis factor-alpha converting enzyme (TACE) is a membrane-anchored, Zn-dependent metalloprotease, which belongs to the ADAM (a disintegrin and metalloprotease) family. TACE functions as a membrane sheddase to release the ectodomain portions of many transmembrane proteins, including the precursors of TNFalpha, TGFalpha, several other cytokines, as well as the receptors for TNFalpha, and neuregulin (ErbB4). Mice with TACE(DeltaZn/DeltaZn) null mutation die at birth with phenotypic changes, including failure of eyelid fusion, hair and skin defects, and abnormalities of lung development. Abnormal fetal heart development was not previously described. Herein, we report that TACE(DeltaZn/DeltaZn) null mutant mice by late gestation exhibit markedly enlarged fetal hearts with increased myocardial trabeculation and reduced cell compaction, mimicking the pathological changes of noncompaction of ventricular myocardium. In addition, larger cardiomyocyte cell size and increased cell proliferation were observed in ventricles of TACE(DeltaZn/DeltaZn) knockout mouse hearts. At the molecular level, reduced expression of epidermal growth factor receptor, attenuated protein cleavage of ErbB4, and changes in MAPK activation were also detected in TACE(DeltaZn/DeltaZn) knockout heart tissues. The data suggest that TACE-mediated cell surface protein ectodomain shedding plays an essential and a novel regulatory role during cardiac development and modeling.
Collapse
Affiliation(s)
- Wei Shi
- Center for Craniofacial Molecular Biology, University of Southern California, 2250 Alcazar St., CSA 103, Los Angeles, CA 90033, USA.
| | | | | | | | | | | | | | | |
Collapse
|