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Lin YC, Sahoo BK, Gau SS, Yang RB. The biology of SCUBE. J Biomed Sci 2023; 30:33. [PMID: 37237303 PMCID: PMC10214685 DOI: 10.1186/s12929-023-00925-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023] Open
Abstract
The SCUBE [Signal peptide-Complement C1r/C1s, Uegf, Bmp1 (CUB)-Epithelial growth factor domain-containing protein] family consists of three proteins in vertebrates, SCUBE1, 2 and 3, which are highly conserved in zebrafish, mice and humans. Each SCUBE gene encodes a polypeptide of approximately 1000 amino acids that is organized into five modular domains: (1) an N-terminal signal peptide sequence, (2) nine tandem epidermal growth factor (EGF)-like repeats, (3) a large spacer region, (4) three cysteine-rich (CR) motifs, and (5) a CUB domain at the C-terminus. Murine Scube genes are expressed individually or in combination during the development of various tissues, including those in the central nervous system and the axial skeleton. The cDNAs of human SCUBE orthologs were originally cloned from vascular endothelial cells, but SCUBE expression has also been found in platelets, mammary ductal epithelium and osteoblasts. Both soluble and membrane-associated SCUBEs have been shown to play important roles in physiology and pathology. For instance, upregulation of SCUBEs has been reported in acute myeloid leukemia, breast cancer and lung cancer. In addition, soluble SCUBE1 is released from activated platelets and can be used as a clinical biomarker for acute coronary syndrome and ischemic stroke. Soluble SCUBE2 enhances distal signaling by facilitating the secretion of dual-lipidated hedgehog from nearby ligand-producing cells in a paracrine manner. Interestingly, the spacer regions and CR motifs can increase or enable SCUBE binding to cell surfaces via electrostatic or glycan-lectin interactions. As such, membrane-associated SCUBEs can function as coreceptors that enhance the signaling activity of various serine/threonine kinase or tyrosine kinase receptors. For example, membrane-associated SCUBE3 functions as a coreceptor that promotes signaling in bone morphogenesis. In humans, SCUBE3 mutations are linked to abnormalities in growth and differentiation of both bones and teeth. In addition to studies on human SCUBE function, experimental results from genetically modified mouse models have yielded important insights in the field of systems biology. In this review, we highlight novel molecular discoveries and critical directions for future research on SCUBE proteins in the context of cancer, skeletal disease and cardiovascular disease.
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Affiliation(s)
- Yuh-Charn Lin
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Binay K Sahoo
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Shiang-Shin Gau
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ruey-Bing Yang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
- Biomedical Translation Research Center, Academia Sinica, Taipei, Taiwan.
- Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, Taipei, Taiwan.
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Imbalance in Bone Morphogenic Proteins 2 and 7 Is Associated with Renal and Cardiovascular Damage in Chronic Kidney Disease. Int J Mol Sci 2022; 24:ijms24010040. [PMID: 36613483 PMCID: PMC9820638 DOI: 10.3390/ijms24010040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/06/2022] [Accepted: 12/11/2022] [Indexed: 12/24/2022] Open
Abstract
Arterial stiffness is a major vascular complication of chronic kidney disease (CKD). The development of renal damage, hypertension, and increased pulse wave velocity (PWV) in CKD might be associated with an imbalance in bone morphogenetic proteins (BMP)-2 and BMP-7. Plasma BMP-2 and BMP-7 were determined by ELISA in CKD patients (stages I-III; n = 95) and Munich Wistar Frömter (MWF) rats. Age-matched Wistar rats were used as a control. The expression of BMP-2, BMP-7, and profibrotic and calcification factors was determined in kidney and perivascular adipose tissues (PVAT). BMP-2 was higher in stage III CKD patients compared to control subjects. BMP-7 was lower at any CKD stage compared to controls, with a significant further reduction in stage III patients. A similar imbalance was observed in MWF rats together with the increase in systolic (SBP) and diastolic blood pressure (DBP), or pulse wave velocity (PWV). MWF exhibited elevated urinary albumin excretion (UAE) and renal expression of BMP-2 or kidney damage markers, Kim-1 and Ngal, whereas renal BMP-7 was significantly lower than in Wistar rats. SBP, DBP, PWV, UAE, and plasma creatinine positively correlated with the plasma BMP-2/BMP-7 ratio. Periaortic and mesenteric PVAT from MWF rats showed an increased expression of BMP-2 and profibrotic and calcification markers compared to Wistar rats, together with a reduced BMP-7 expression. BMP-2 and BMP-7 imbalance in plasma, kidney, and PVATs is associated with vascular damage, suggesting a profibrotic/pro-calcifying propensity associated with progressive CKD. Thus, their combined analysis stratified by CKD stages might be of clinical interest to provide information about the degree of renal and vascular damage in CKD.
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Harnessing the Physiological Functions of Cellular Prion Protein in the Kidneys: Applications for Treating Renal Diseases. Biomolecules 2021; 11:biom11060784. [PMID: 34067472 PMCID: PMC8224798 DOI: 10.3390/biom11060784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 12/16/2022] Open
Abstract
A cellular prion protein (PrPC) is a ubiquitous cell surface glycoprotein, and its physiological functions have been receiving increased attention. Endogenous PrPC is present in various kidney tissues and undergoes glomerular filtration. In prion diseases, abnormal prion proteins are found to accumulate in renal tissues and filtered into urine. Urinary prion protein could serve as a diagnostic biomarker. PrPC plays a role in cellular signaling pathways, reno-protective effects, and kidney iron uptake. PrPC signaling affects mitochondrial function via the ERK pathway and is affected by the regulatory influence of microRNAs, small molecules, and signaling proteins. Targeting PrPC in acute and chronic kidney disease could help improve iron homeostasis, ameliorate damage from ischemia/reperfusion injury, and enhance the efficacy of mesenchymal stem/stromal cell or extracellular vesicle-based therapeutic strategies. PrPC may also be under the influence of BMP/Smad signaling and affect the progression of TGF-β-related renal fibrosis. PrPC conveys TNF-α resistance in some renal cancers, and therefore, the coadministration of anti-PrPC antibodies improves chemotherapy. PrPC can be used to design antibody-drug conjugates, aptamer-drug conjugates, and customized tissue inhibitors of metalloproteinases to suppress cancer. With preclinical studies demonstrating promising results, further research on PrPC in the kidney may lead to innovative PrPC-based therapeutic strategies for renal disease.
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Gao L, Zhong X, Jin J, Li J, Meng XM. Potential targeted therapy and diagnosis based on novel insight into growth factors, receptors, and downstream effectors in acute kidney injury and acute kidney injury-chronic kidney disease progression. Signal Transduct Target Ther 2020; 5:9. [PMID: 32296020 PMCID: PMC7018831 DOI: 10.1038/s41392-020-0106-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Revised: 12/01/2019] [Accepted: 12/17/2019] [Indexed: 02/08/2023] Open
Abstract
Acute kidney injury (AKI) is defined as a rapid decline in renal function and is characterized by excessive renal inflammation and programmed death of resident cells. AKI shows high morbidity and mortality, and severe or repeated AKI can transition to chronic kidney disease (CKD) or even end-stage renal disease (ESRD); however, very few effective and specific therapies are available, except for supportive treatment. Growth factors, such as epidermal growth factor (EGF), insulin-like growth factor (IGF), and transforming growth factor-β (TGF-β), are significantly altered in AKI models and have been suggested to play critical roles in the repair process of AKI because of their roles in cell regeneration and renal repair. In recent years, a series of studies have shown evidence that growth factors, receptors, and downstream effectors may be highly involved in the mechanism of AKI and may function in the early stage of AKI in response to stimuli by regulating inflammation and programmed cell death. Moreover, certain growth factors or correlated proteins act as biomarkers for AKI due to their sensitivity and specificity. Furthermore, growth factors originating from mesenchymal stem cells (MSCs) via paracrine signaling or extracellular vesicles recruit leukocytes or repair intrinsic cells and may participate in AKI repair or the AKI-CKD transition. In addition, growth factor-modified MSCs show superior therapeutic potential compared to that of unmodified controls. In this review, we summarized the current therapeutic and diagnostic strategies targeting growth factors to treat AKI in clinical trials. We also evaluated the possibilities of other growth factor-correlated molecules as therapeutic targets in the treatment of AKI and the AKI-CKD transition.
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Affiliation(s)
- Li Gao
- The Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, 230032, Hefei, China
| | - Xiang Zhong
- Department of Nephrology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, 610072, Chengdu, Sichuan, China
| | - Juan Jin
- Department of Pharmacology, Key Laboratory of Anti-inflammatory and Immunopharmacology, Ministry of Education, Anhui Medical University, 230032, Hefei, China
| | - Jun Li
- The Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, 230032, Hefei, China
| | - Xiao-Ming Meng
- The Key Laboratory of Major Autoimmune Diseases, Anhui Institute of Innovative Drugs, School of Pharmacy, Anhui Medical University, 230032, Hefei, China.
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Lu L, Zhu J, Zhang Y, Wang Y, Zhang S, Xia A. Febuxostat inhibits TGF‑β1‑induced epithelial‑mesenchymal transition via downregulation of USAG‑1 expression in Madin‑Darby canine kidney cells in vitro. Mol Med Rep 2019; 19:1694-1704. [PMID: 30628645 PMCID: PMC6390060 DOI: 10.3892/mmr.2019.9806] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 12/04/2018] [Indexed: 01/06/2023] Open
Abstract
Our previous study demonstrated that febuxostat, a xanthine oxidase inhibitor, can alleviate kidney dysfunction and ameliorate renal tubulointerstitial fibrosis in a rat unilateral ureteral obstruction (UUO) model; however, the underlying mechanisms remain unknown. Increasing evidence has revealed that epithelial-mesenchymal transition (EMT) is one of the key mechanisms mediating the progression of renal tubulointerstitial fibrosis in chronic kidney disease (CKD). Uterine sensitization-associated gene-1 (USAG-1), a kidney-specific bone morphogenetic protein antagonist, is involved in the development of numerous types of CKDs. The present study aimed to investigate the role of febuxostat in the process of EMT in Madin-Darby canine kidney (MDCK) cells in vitro. Western blotting, reverse transcription-semiquantitative polymerase chain reaction analysis and immunofluorescence staining were used to evaluate the expression levels of bone morphogenetic protein 7, USAG-1, α-smooth muscle actin (α-SMA) and E-cadherin, respectively. The results demonstrated that the expression of USAG-1 and α-SMA increased, and that of E-cadherin decreased significantly in MDCK cells following treatment with transforming growth factor-β1 (TGF-β1). The application of small interfering RNA-USAG-1 potently inhibited TGF-β1-induced EMT. Subsequently, the effects of febuxostat on TGF-β1-induced EMT was investigated. The results demonstrated that febuxostat downregulated the expression of USAG-1, and reversed TGF-β1-induced EMT in MDCK cells. Furthermore, pretreatment with febuxostat significantly restored the decreased expression levels of phosphorylated Smad1/5/8 induced by TGF-β1 in MDCK cells. The results of the present study suggested that USAG-1 may be involved in the EMT process of MDCK cells induced by TGF-β1, and febuxostat inhibited EMT by activating the Smad1/5/8 signaling pathway via downregulating the expression of USAG-1 in MDCK cells.
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Affiliation(s)
- Linghong Lu
- Department of Pharmacology, Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China
| | - Jiajun Zhu
- Department of Anesthesiology, Guanyun County People's Hospital, Lianyungang, Jiangsu 222200, P.R. China
| | - Yaqian Zhang
- Department of Pharmacology, Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China
| | - Yanxia Wang
- Department of Pharmacology, Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China
| | - Shu Zhang
- Department of Pharmacology, Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China
| | - Anzhou Xia
- Department of Pharmacology, Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China
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SCUBE1-enhanced bone morphogenetic protein signaling protects against renal ischemia-reperfusion injury. Biochim Biophys Acta Mol Basis Dis 2018; 1865:329-338. [PMID: 30414502 DOI: 10.1016/j.bbadis.2018.10.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 10/30/2018] [Indexed: 12/15/2022]
Abstract
We previously reported that the membrane-bound SCUBE1 (signal peptide-CUB-epithelial growth factor domain-containing protein 1) forms a complex with bone morphogenetic protein 2 (BMP2) ligand and its receptors, thus acting as a BMP co-receptor to augment BMP signal activity. However, whether SCUBE1 can bind to and facilitate signaling activity of BMP7, a renal protective molecule for ischemia-reperfusion (I/R) insult, and contribute to the proliferation and repair of renal tubular cells after I/R remains largely unknown. In this study, we first showed that I/R-induced SCUBE1 was expressed in proximal tubular cells, which coincided with the expression of renoprotective BMP7. Molecular and biochemical analyses revealed that SCUBE1 directly binds to BMP7 and its receptors, functioning as a BMP co-receptor to promote BMP7 signaling. Furthermore, we used a new Scube1 deletion (Δ2) mouse strain to further elucidate the renal pathophysiological function of SCUBE1 after I/R injury. As compared with wild-type littermates, Δ2 mice showed severe renal histopathologic features (extensive loss of brush border, tubular necrosis, and tubular dilation) and increased inflammation (neutrophil infiltrate and induction of monocyte chemoattractant protein-1, tumor necrosis factor-α and interleukin-6) during the resolution of I/R damage. They also showed reduced BMP signaling (phosphorylated Smad1/5/8) along with decreased proliferation and increased apoptosis of renal tubular cells. Importantly, lentivirus-mediated overexpression of SCUBE1 enhanced BMP signaling and conferred a concomitant survival outcome for Δ2 proximal tubular epithelial cells after hypoxia-reoxygenation treatment. The protective BMP7 signaling may be facilitated by stress-inducible SCUBE1 after renal I/R, which suggests potential targeted approaches for acute kidney injury.
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Abstract
Kidney diseases including acute kidney injury and chronic kidney disease are among the largest health issues worldwide. Dialysis and kidney transplantation can replace a significant portion of renal function, however these treatments still have limitations. To overcome these shortcomings, a variety of innovative efforts have been introduced, including cell-based therapies. During the past decades, advances have been made in the stem cell and developmental biology, and tissue engineering. As part of such efforts, studies on renal cell therapy and artificial kidney developments have been conducted, and multiple therapeutic interventions have shown promise in the pre-clinical and clinical settings. More recently, therapeutic cell-secreting secretomes have emerged as a potential alternative to cell-based approaches. This approach involves the use of renotropic factors, such as growth factors and cytokines, that are produced by cells and these factors have shown effectiveness in facilitating kidney function recovery. This review focuses on the renotropic functions of bioactive compounds that provide protective and regenerative effects for kidney tissue repair, based on the available data in the literature.
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Affiliation(s)
- Kang Su Cho
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
- Department of Urology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - In Kap Ko
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - James J Yoo
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, USA.
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Higgins DF, Ewart LM, Masterson E, Tennant S, Grebnev G, Prunotto M, Pomposiello S, Conde-Knape K, Martin FM, Godson C. BMP7-induced-Pten inhibits Akt and prevents renal fibrosis. Biochim Biophys Acta Mol Basis Dis 2017; 1863:3095-3104. [PMID: 28923783 DOI: 10.1016/j.bbadis.2017.09.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 09/12/2017] [Accepted: 09/14/2017] [Indexed: 12/18/2022]
Abstract
Bone morphogenetic protein-7 (BMP-7) counteracts pro-fibrotic effects of TGFβ1 in cultured renal cells and protects from fibrosis in acute and chronic renal injury models. Using the unilateral ureteral obstruction (UUO) model of chronic renal fibrosis, we investigated the effect of exogenous-rhBMP-7 on pro-fibrotic signaling pathways mediated by TGFβ1 and hypoxia. Mice undergoing UUO were treated with vehicle or rhBMP-7 (300μg/kg i.p.) every other day for eight days and kidneys analysed for markers of fibrosis and SMAD, MAPK, and PI3K signaling. In the kidney, collecting duct and tubular epithelial cells respond to BMP-7 via activation of SMAD1/5/8. Phosphorylation of SMAD1/5/8 was reduced in UUO kidneys from vehicle-treated animals yet maintained in UUO kidneys from BMP-7-treated animals, confirming renal bioactivity of exogenous rhBMP-7. BMP-7 inhibited Collagen Iα1 and Collagen IIIα1 gene expression and Collagen I protein accumulation, while increasing expression of Collagen IVα1 in UUO kidneys. Activation of SMAD2, SMAD3, ERK, p38 and PI3K/Akt signaling occurred during fibrogenesis and BMP-7 significantly attenuated SMAD3 and Akt signaling in vivo. Analysis of renal collecting duct (mIMCD) and tubular epithelial (HK-2) cells stimulated with TGFβ1 or hypoxia (1% oxygen) to activate Akt provided further evidence that BMP-7 specifically inhibited PI3K/Akt signaling. PTEN is a negative regulator of PI3K and BMP-7 increased PTEN expression in vivo and in vitro. These data demonstrate an important mechanism by which BMP-7 orchestrates renal protection through Akt inhibition and highlights Akt inhibitors as anti-fibrotic therapeutics.
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Affiliation(s)
- Debra F Higgins
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland.
| | - Leah M Ewart
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Enda Masterson
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Sadhbh Tennant
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Gleb Grebnev
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Marco Prunotto
- F. Hoffmann-La Roche, Dept of Metabolic and Vascular Disease, CH4070 Basel, Switzerland
| | - Sylvia Pomposiello
- F. Hoffmann-La Roche, Dept of Metabolic and Vascular Disease, CH4070 Basel, Switzerland
| | - Karin Conde-Knape
- F. Hoffmann-La Roche, Dept of Metabolic and Vascular Disease, CH4070 Basel, Switzerland
| | - Finian M Martin
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Catherine Godson
- UCD Diabetes Complications Research Centre, School of Medicine, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
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Krasilnikova AA, Solovieva AO, Trifonova KE, Brylev KA, Ivanov AA, Kim SJ, Shestopalov MA, Fufaeva MS, Shestopalov AM, Mironov YV, Poveshchenko AF, Shestopalova LV. Cellular internalization and morphological analysis after intravenous injection of a highly hydrophilic octahedral rhenium cluster complex - a new promising X-ray contrast agent. CONTRAST MEDIA & MOLECULAR IMAGING 2016; 11:459-466. [PMID: 27491502 DOI: 10.1002/cmmi.1707] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 06/24/2016] [Accepted: 07/01/2016] [Indexed: 11/05/2022]
Abstract
The octahedral cluster compound Na2 H8 [{Re6 Se8 }(P(C2 H4 CONH2 )(C2 H4 COO)2 )6 ] has been shown to be highly radio dense, thus becoming a promising X-ray contrast agent. It was also shown that this compound had low cytotoxic effect in vitro, low acute toxicity in vivo and was eliminated rapidly from the body through the urinary tract. The present contribution describes a more detailed cellular internalization assay and morphological analysis after intravenous injection of this hexarhenium cluster compound at different doses. The median lethal dose (LD50 ) of intravenously administrated compound was calculated (4.67 ± 0.69 g/kg). Results of the study clearly indicated that the cluster complex Hn [{Re6 Se8 }(P(C2 H4 CONH2 )(C2 H4 COO)2 )6 ]n-10 was not internalized into cells in vitro and induced only moderate morphological alterations of kidneys at high doses without any changes in morphology of liver, spleen, duodenum, or heart of mice. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Anna A Krasilnikova
- Federal State Budgetary Scientific Institution "Scientific Institute of Clinical and Experimental Lymphology", Novosibirsk, Russian Federation.,Novosibirsk State University, Novosibirsk, Russian Federation.,Federal State Budgetary Scientific Institution "Research Institute of Experimental and Clinical Medicine", Novosibirsk, Russian Federation
| | - Anastasiya O Solovieva
- Federal State Budgetary Scientific Institution "Scientific Institute of Clinical and Experimental Lymphology", Novosibirsk, Russian Federation
| | - Kristina E Trifonova
- Federal State Budgetary Scientific Institution "Scientific Institute of Clinical and Experimental Lymphology", Novosibirsk, Russian Federation.,The State Research Center of Virology and Biotechnology VECTOR, Koltsovo, Novosibirsk Region, Russian Federation
| | - Konstantin A Brylev
- Novosibirsk State University, Novosibirsk, Russian Federation.,Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk, Russian Federation.,Department of Chemistry and Nano Science, Ewha Womans University, Seoul, Korea
| | - Anton A Ivanov
- Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk, Russian Federation
| | - Sung-Jin Kim
- Department of Chemistry and Nano Science, Ewha Womans University, Seoul, Korea
| | - Michael A Shestopalov
- Novosibirsk State University, Novosibirsk, Russian Federation.,Federal State Budgetary Scientific Institution "Research Institute of Experimental and Clinical Medicine", Novosibirsk, Russian Federation.,Nikolaev Institute of Inorganic Chemistry SB RAS, Novosibirsk, Russian Federation
| | - Maria S Fufaeva
- Federal State Budgetary Scientific Institution "Research Institute of Experimental and Clinical Medicine", Novosibirsk, Russian Federation
| | - Alexander M Shestopalov
- Federal State Budgetary Scientific Institution "Research Institute of Experimental and Clinical Medicine", Novosibirsk, Russian Federation
| | - Yuri V Mironov
- Novosibirsk State University, Novosibirsk, Russian Federation.,Federal State Budgetary Scientific Institution "Research Institute of Experimental and Clinical Medicine", Novosibirsk, Russian Federation
| | - Alexander F Poveshchenko
- Federal State Budgetary Scientific Institution "Scientific Institute of Clinical and Experimental Lymphology", Novosibirsk, Russian Federation
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Dube PH, Almanzar MM, Frazier KS, Jones WK, Charette MF, Paredes A. Osteogenic Protein-1: Gene Expression and Treatment in the Rat Remnant Kidney Model. Toxicol Pathol 2016; 32:384-92. [PMID: 15307210 DOI: 10.1080/01926230490440925] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Osteogenic Protein-1 (OP-1) is a bone morphogen involved in tissue repair and development. We have shown that OP-1 is downregulated during acute ischemic renal injury. Here we report the use of the rat remnant kidney model (RRKM) to evaluate changes in kidney OP-1 expression during chronic injury, and determine if treatment with recombinant human OP-1 (rhOP-1) aids in recovery from injury. Sprague—Dawley rats were subjected to kidney decapsulation (Cx) or 5/6 nephrectomy (Nx). Serum for BUN and creatinine and tissue for histology and mRNA analysis were collected at: 2, 10, and 12—14 wks post Nx. We show kidney OP-1 mRNA levels were downregulated at 2 and 12—14 wks post Nx. To determine the effect of rhOP-1 in the RRKM, rhOP-1 (0.25, 2.5 or 25 μg/kg) or vehicle (V) was injected in a second set of rats, 2 weeks after 2/3 left Nx for a total of six doses. Nx rats treated with rhOP-1 showed significantly increased tubular regeneration (increased mitotic figures, polyoid infolding, and tubular epithelial hyperplasia) in a dose dependent manner without changes in glomerular or tubular damage. rhOP-1 stimulates tubular epithelial cell regeneration, early in the repair process in a chronic renal failure model, before significant fibrosis is established.
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Affiliation(s)
- Philip H Dube
- Department of Nephrology, Miami Children's Hospital, Miami, Florida, USA
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11
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Manson SR, Austin PF, Guo Q, Moore KH. BMP-7 Signaling and its Critical Roles in Kidney Development, the Responses to Renal Injury, and Chronic Kidney Disease. VITAMINS AND HORMONES 2016; 99:91-144. [PMID: 26279374 DOI: 10.1016/bs.vh.2015.05.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chronic kidney disease (CKD) is a significant health problem that most commonly results from congenital abnormalities in children and chronic renal injury in adults. The therapeutic potential of BMP-7 was first recognized nearly two decades ago with studies demonstrating its requirement for kidney development and ability to inhibit the pathogenesis of renal injury in models of CKD. Since this time, our understanding of CKD has advanced considerably and treatment strategies have evolved with the identification of many additional signaling pathways, cell types, and pathologic processes that contribute to disease progression. The purpose of this review is to revisit the seminal studies that initially established the importance of BMP-7, highlight recent advances in BMP-7 research, and then integrate this knowledge with current research paradigms. We will provide an overview of the evolutionarily conserved roles of BMP proteins and the features that allow BMP signaling pathways to function as critical signaling nodes for controlling biological processes, including those related to CKD. We will discuss the multifaceted functions of BMP-7 during kidney development and the potential for alterations in BMP-7 signaling to result in congenital abnormalities and pediatric kidney disease. We will summarize the renal protective effects of recombinant BMP-7 in experimental models of CKD and then propose a model to describe the potential physiological role of endogenous BMP-7 in the innate repair mechanisms of the kidneys that respond to renal injury. Finally, we will highlight emerging clinical approaches for applying our knowledge of BMP-7 toward improving the treatment of patients with CKD.
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Affiliation(s)
- Scott R Manson
- Department of Surgery, Division of Urology, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, Missouri, USA.
| | - Paul F Austin
- Department of Surgery, Division of Urology, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Qiusha Guo
- Department of Surgery, Division of Urology, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, Missouri, USA
| | - Katelynn H Moore
- Department of Surgery, Division of Urology, Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, Missouri, USA
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Abstract
A number of genes involved in kidney development are reactivated in the adult after acute kidney injury (AKI). This has led to the belief that tissue repair mechanisms recapitulate pathways involved in embryonic development after AKI. We will discuss evidence to support this hypothesis by comparing the mechanisms of development with common pathways known to regulate post-AKI repair, or that we identified as cell-specific candidates based on public datasets from recent AKI translational profiling studies. We will argue that while many of these developmental pathways are reactivated after AKI, this is not associated with general cellular reprogramming to an embryonic state. We will show that reactivation of these developmental genes is often associated with expression in cells that are not normally involved in mediating parallel responses in the embryo, and that depending on the cellular context, these responses can have beneficial or detrimental effects on injury and repair after AKI.
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Cirio MC, de Groh ED, de Caestecker MP, Davidson AJ, Hukriede NA. Kidney regeneration: common themes from the embryo to the adult. Pediatr Nephrol 2014; 29:553-64. [PMID: 24005792 PMCID: PMC3944192 DOI: 10.1007/s00467-013-2597-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 07/26/2013] [Accepted: 07/29/2013] [Indexed: 02/07/2023]
Abstract
The vertebrate kidney has an inherent ability to regenerate following acute damage. Successful regeneration of the injured kidney requires the rapid replacement of damaged tubular epithelial cells and reconstitution of normal tubular function. Identifying the cells that participate in the regeneration process as well as the molecular mechanisms involved may reveal therapeutic targets for the treatment of kidney disease. Renal regeneration is associated with the expression of genetic pathways that are necessary for kidney organogenesis, suggesting that the regenerating tubular epithelium may be "reprogrammed" to a less-differentiated, progenitor state. This review will highlight data from various vertebrate models supporting the hypothesis that nephrogenic genes are reactivated as part of the process of kidney regeneration following acute kidney injury (AKI). Emphasis will be placed on the reactivation of developmental pathways and how our understanding of the resulting regeneration process may be enhanced by lessons learned in the embryonic kidney.
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Affiliation(s)
- M. Cecilia Cirio
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Eric D. de Groh
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Mark P. de Caestecker
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Alan J. Davidson
- Department of Molecular Medicine and Pathology, School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - Neil A. Hukriede
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA, United States of America
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An update on the pathomechanisms and future therapies of Alport syndrome. Pediatr Nephrol 2013; 28:1025-36. [PMID: 22903660 DOI: 10.1007/s00467-012-2272-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 07/12/2012] [Accepted: 07/13/2012] [Indexed: 01/08/2023]
Abstract
Alport Syndrome (AS) is an inherited progressive disease that is caused by mutations of the genes encoding the key collagen chains, α3, α4, and α5, which are necessary for the composition of collagen type IV to form a robust glomerular basement membrane (GBM), capable of withstanding the significant biomechanical strain to which the glomerulus is subjected. Progressive loss of the filtration barrier allows excessive proteinuria, which ultimately leads to end-stage kidney disease (ESKD). The evidence for a beneficial renoprotective effect of renin-angiotensin-aldosterone system (RAAS) blockade by angiotensin-converting enzyme (ACE) inhibition and/or angiotensin receptor blockers (ARBs) is well established in AS and recent evidence has shown that it can significantly delay the time to onset of renal replacement therapy and ESKD. Future potential treatments of AS disease progression are evaluated in this review.
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Xu JH, Zhang TZ, Zhao YY, Wang JK, Yuan ZG. Protective effects of recombinant human bone morphogenetic protein-7 on focal cerebral ischemia-reperfusion injury. Int J Neurosci 2013; 123:375-84. [PMID: 23327662 DOI: 10.3109/00207454.2012.761614] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study was to investigate the protective effect of recombinant human bone morphogenetic protein-7 (rhBMP-7) on focal cerebral ischemia-reperfusion (IR) injuries and their underlying mechanisms. An intraluminal suture method was used to generate a middle cerebral artery occlusion model in rats, which was followed by reperfusion. A sham operation (SO) group underwent the procedure without occlusion, whereas an IR group and rhBMP-7 treated group (RT) underwent occlusion in the absence and presence of rhBMP-7 (250 μg/kg) administered via a femoral vein injection 30 minutes prior to reperfusion. Twenty-four hours after reperfusion, neurological function, brain water content and morphological alterations were examined. Apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assays, and immunohistochemical staining and Western blot assays were used to detect nuclear nuclear factor-kappa B (NF-κB) p65 expression. Compared with the SO group, IR rats showed a decrease in neurological function, an increase in brain water content, and pathological and morphological damage (p < 0.05). Higher levels of apoptosis were also detected in the infarct region area. In contrast, RT rats had reduced injury after IR. In addition, while immunohistochemical staining and western blot assays consistently detected increased expression of nuclear NF-κB after IR, these levels were reduced in the RT group. Administration of rhBMP-7 prior to reperfusion effectively inhibited the extent of IR injury by attenuating cerebral edema and ameliorating ultrastructural damage. The underlying mechanisms responsible for these observations potentially involve the inhibition of apoptosis induced by IR by rhBMP-7 via an NF-κB-related signaling cascade.
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Affiliation(s)
- Ji-Hong Xu
- Department of Anesthesiology, General Hospital of Shenyang Military Region, Shenyang, China
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16
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Frazier KS, Seely JC, Hard GC, Betton G, Burnett R, Nakatsuji S, Nishikawa A, Durchfeld-Meyer B, Bube A. Proliferative and nonproliferative lesions of the rat and mouse urinary system. Toxicol Pathol 2012; 40:14S-86S. [PMID: 22637735 DOI: 10.1177/0192623312438736] [Citation(s) in RCA: 202] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The INHAND Project (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying lesions observed in the urinary tract of rats and mice. The standardized nomenclature of urinary tract lesions presented in this document is also available electronically on the Internet (http://www.goreni.org/). Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous developmental and aging lesions as well as those induced by exposure to test materials. A widely accepted and utilized international harmonization of nomenclature for urinary tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists.
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Affiliation(s)
- Kendall S Frazier
- GlaxoSmithKline-Safety Assessment, King of Prussia, Pennsylvania 19406, USA.
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17
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Wan JX, Zou ZH, You DY, Cui J, Pan YB. Bone marrow-derived mesenchymal stem cells differentiation into tubular epithelial-like cells in vitro. Cell Biochem Funct 2011; 30:129-38. [PMID: 22125055 DOI: 10.1002/cbf.1826] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Revised: 08/03/2011] [Accepted: 09/28/2011] [Indexed: 11/05/2022]
Abstract
The possibility of differentiating bone marrow-derived mesenchymal stem cells (BMSCs) into tubular epithelial-like cells is explored in vitro. Purified BMSCs from Sprague-Dawley rats were obtained by density gradient centrifugation. Third generation BMSCs were divided into six groups and were cultured under different conditions. The expression of alkaline phosphatase and cytokeratin (CK)-18 protein was detected through staining and immunocytochemistry, respectively, and the expression of E-cadherin proteins was recorded through immunofluorescence. Some cells in ischemia/reperfusion (I/R), all-trans retinoic acid (ATRA), epidermal growth factor (EGF) and bone morphogenetic protein-7 (BMP-7) groups turned positive, whereas the positive cells in the combined group significantly increased compared with the other groups. Compared with the control group, the positive expression rates of CK-18 in the I/R, ATRA, EGF, BMP-7 and the combined group were 11·50% ± 3·84%, 27·40% ± 2·70%, 29·60% ± 4·51%, 26·80% ± 5·00% and 44·00% ± 3·16%, respectively, and CK-18 mRNA expression in the combined group was obviously higher than that in the other groups (P < 0·01). Immunofluorescence detection showed that E-cadherin expression was not detectable in the control group, whereas the positive expression rates of E-cadherin in the I/R, ATRA, EGF, BMP-7 and the combined group were 6·75% ± 2·13%, 16·40% ± 2·69%, 18·25% ± 3·50%, 16·06% ± 2·00% and 30·26% ± 5·16%, respectively. The addition of ATRA, EGF and BMP-7 induces BMSCs differentiation into tubular epithelial-like cells in stimulated acute renal failure microenvironment in vitro.
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Affiliation(s)
- Jian-Xin Wan
- Department of Nephrology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China.
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18
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Celic T, Spanjol J, Grskovic A, Markic D, Prebilic I, Fuckar Z, Bobinac D. Bone Morphogenetic Protein-7 Reduces Cold Ischemic Injury in Rat Kidney. Transplant Proc 2011; 43:2505-9. [DOI: 10.1016/j.transproceed.2011.05.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Accepted: 05/02/2011] [Indexed: 01/22/2023]
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Oxburgh L. Control of the bone morphogenetic protein 7 gene in developmental and adult life. Curr Genomics 2011; 10:223-30. [PMID: 19949543 PMCID: PMC2709933 DOI: 10.2174/138920209788488490] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Revised: 03/20/2009] [Accepted: 03/20/2009] [Indexed: 11/24/2022] Open
Abstract
The TGFβ superfamily growth factor BMP7 performs essential biological functions in embryonic development and regeneration of injured tissue in the adult. BMP7 activity is regulated at numerous levels in the signaling pathway by the expression of extracellular antagonists, decoy receptors and inhibitory cell signaling components. Additionally, expression of the BMP7 gene is tightly controlled both during embryonic development and adult life. In this review, the current status of work on regulation of BMP7 at the genomic level is discussed. In situ hybridization and reporter gene studies have conclusively defined patterns of BMP7 expression in many tissues. Additionally, both in vivo and cell culture studies have defined some of the mechanistic bases for this regulation. In addition to transcriptional activation mediated by binding of activating transcription factors, there is also strong evidence for repression through recruitment of histone modifying enzymes to specific genetic elements. This review summarizes our current understanding of BMP7 gene regulation in embryonic development and adult tissues.
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Affiliation(s)
- Leif Oxburgh
- Center for Molecular Medicine, Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA
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20
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Duranay M, Segall L, Sen N, Yilmaz FM, Cetin M, Isleyen A, Kanbay M, Covic A. Bone morphogenic protein-7 serum level decreases significantly in patients with contrast-induced nephropathy. Int Urol Nephrol 2010; 43:807-12. [PMID: 21069567 DOI: 10.1007/s11255-010-9871-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Accepted: 10/25/2010] [Indexed: 11/24/2022]
Affiliation(s)
- Murat Duranay
- Department of Internal Medicine, Section of Nephrology, Ankara Training and Research Hospital, Ankara, Turkey
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21
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Nguyen TQ, Goldschmeding R. Bone Morphogenetic Protein-7 and Connective Tissue Growth Factor: Novel Targets for Treatment of Renal Fibrosis? Pharm Res 2008; 25:2416-26. [DOI: 10.1007/s11095-008-9548-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2007] [Accepted: 01/28/2008] [Indexed: 12/11/2022]
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22
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Wetzel P, Haag J, Câmpean V, Goldschmeding R, Atalla A, Amann K, Aigner T. Bone morphogenetic protein-7 expression and activity in the human adult normal kidney is predominantly localized to the distal nephron. Kidney Int 2006; 70:717-23. [PMID: 16807538 DOI: 10.1038/sj.ki.5001653] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Bone morphogenetic protein-7 (BMP)-7 plays an important role during fetal kidney development. In the adult, BMP-7 is most strongly expressed in the kidney compared to other organs, but the exact expression pattern as well as the function of BMP-7 is unclear. The major aim of the present study was to define which parts of the human kidney do physiologically express BMP-7 and which cells appear to be targets of BMP activity by showing phosphorylated BMP-receptor-associated Smads 1, 5, or 8 and inhibitor of differentiation factor 1 (ID1) expression. BMP-7 expression was localized by immunohistology to the epithelia of the distal tubule as well as the collecting ducts (CDs). Phospho-Smads 1/5/8 and ID1 expression largely colocalized with BMP-7 and was also localized in the epithelia of the distal tubule and the CDs. This was confirmed by polymerase chain reaction-based mRNA expression analysis. In vitro, proximal tubular cells (PTCs) expressed BMP receptors and BMP-receptor-associated Smads and were reactive to BMP-7. Our data indicate that BMP-7 expression in the adult human kidney appears to be more restricted than in the fetal situation and predominantly found in the distal nephron. Also, evidence of in vivo BMP signalling (i.e. phospho-Smads and ID1 expression) was found there. These findings suggest that BMP-7 plays a physiological role mostly in this part of the kidney. Still, as reported previously, PTCs are responsive to BMP-7, but presumably not in an autocrine or paracrine mode in normal adult kidneys.
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Affiliation(s)
- P Wetzel
- Osteoarticular and Arthritis Research, Department of Pathology, University of Erlangen-Nürnberg, Erlangen, FRG
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23
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Yanagita M, Okuda T, Endo S, Tanaka M, Takahashi K, Sugiyama F, Kunita S, Takahashi S, Fukatsu A, Yanagisawa M, Kita T, Sakurai T. Uterine sensitization-associated gene-1 (USAG-1), a novel BMP antagonist expressed in the kidney, accelerates tubular injury. J Clin Invest 2005; 116:70-9. [PMID: 16341262 PMCID: PMC1307562 DOI: 10.1172/jci25445] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Accepted: 10/11/2005] [Indexed: 12/15/2022] Open
Abstract
Dialysis dependency is one of the leading causes of morbidity and mortality in the world, and once end-stage renal disease develops, it cannot be reversed by currently available therapy. Although administration of large doses of bone morphogenetic protein-7 (BMP-7) has been shown to repair established renal injury and improve renal function, the pathophysiological role of endogenous BMP-7 and regulatory mechanism of its activities remain elusive. Here we show that the product of uterine sensitization-associated gene-1 (USAG1), a novel BMP antagonist abundantly expressed in the kidney, is the central negative regulator of BMP function in the kidney and that mice lacking USAG-1 (USAG1 mice) are resistant to renal injury. USAG1 mice exhibited prolonged survival and preserved renal function in acute and chronic renal injury models. Renal BMP signaling, assessed by phosphorylation of Smad proteins, was significantly enhanced in USAG1 mice with renal injury, indicating that the preservation of renal function is attributable to enhancement of endogenous BMP signaling. Furthermore, the administration of neutralizing antibody against BMP-7 abolished renoprotection in USAG1 mice, indicating that USAG-1 plays a critical role in the modulation of renoprotective action of BMP and that inhibition of USAG-1 is a promising means of development of novel treatment for renal diseases.
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Affiliation(s)
- Motoko Yanagita
- COE Formation for Genomic Analysis of Disease Model Animals with Multiple Genetic Alterations, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
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25
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Biyikli NK, Tugtepe H, Cakalagaoglu F, Ilki A, Alpay H. Downregulation of the expression of bone morphogenetic protein 7 in experimental pyelonephritis. Pediatr Nephrol 2005; 20:1230-6. [PMID: 16034630 DOI: 10.1007/s00467-005-1927-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Revised: 02/23/2005] [Accepted: 02/23/2005] [Indexed: 10/25/2022]
Abstract
Bone morphogenetic protein 7 (BMP 7) is a member of the transforming growth factor (TGF) beta superfamily and is involved in regeneration, repair, and development of specific tissues, for example kidney, gut, lens, and skeleton. BMP 7 has emerged as a renotrophic factor and experimental studies have shown its protective role against fibrotic processes. Tubulointerstitial changes are present in the pyelonephritic kidney which progresses to fibrosis. Renal fibrosis may lead to significant morbidity in the form of hypertension, proteinuria, and loss of renal function. The objective of this study was to investigate BMP 7 expression in experimental acute and chronic pyelonephritis models. Eighteen Wistar rats were injected with 0.1 mL solution containing E. coli ATCC 25922 10(10) cfu mL(-1) into left renal medullae. Six rats were used as a sham group and were given 0.1 mL 0.9% NaCl. Pyelonephritic rats were sacrificed 24 h (group I, n=6), 1 week (group II, n=6), and 6 weeks (group III, n=6) after E. coli injection. Serum creatinine levels were analyzed. Renal tissues were studied histopathologically by use of hematoxylin and eosin and scored for diagnosis of pyelonephritis. BMP 7 expression was studied semiquantitatively by immunohistochemical staining. Acute (group I) and chronic (group II and group III) pyelonephritic histopathological changes were observed in experimental pyelonephritic groups. A gradual decrease in BMP 7 expression was observed in the tubulointerstitial and tubular area of the pyelonephritic kidneys, mildest in the acute pyelonephritic group and most severe in the chronic pyelonephritic 6th week group. A statistically significant difference was observed between tubulointerstitial BMP 7 expression by groups I and III (P=0.017) and by groups III and IV (P=0.000). Tubular BMP 7 expression was statistically significantly different between groups II and IV (P=0.009) and between groups III and IV (P=0.002). The data imply that BMP 7 has a major role in chronic pyelonephritis. Tubulointerstitial and tubular BMP 7 expression also had a significant negative correlation with fibrosis, tubular, atrophy, and vascular changes. Serum creatinine levels of the study group were all normal. We conclude that the decrease in renal BMP 7 expression in experimental chronic pyelonephritis is one of the factors responsible for fibrotic changes in persistent renal damage.
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Affiliation(s)
- Nese Karaaslan Biyikli
- Department of Pediatric Nephrology, Marmara University School of Medicine, Tophanelioglu cd No. 13-15, 81190 Altunizade, Istanbul, Turkey.
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26
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Simic P, Vukicevic S. Bone morphogenetic proteins in development and homeostasis of kidney. Cytokine Growth Factor Rev 2005; 16:299-308. [PMID: 15923134 DOI: 10.1016/j.cytogfr.2005.02.010] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2004] [Accepted: 02/17/2005] [Indexed: 01/01/2023]
Abstract
Bone morphogenetic proteins play a key role in kidney development and postnatal function. The kidney has been identified as a major site of bone morphogenetic protein (BMP)-7 synthesis during embryonic and postnatal development, which mediates differentiation and maintenance of metanephric mesenchyme. Targeted disruption of BMP-7 gene expression in mice resulted in dysgenic kidneys with hydroureters, causing uremia within 24h after birth. Several experimental animal models of acute and chronic renal injury have all unequivocally shown beneficial effect of BMP-7 in ameliorating the severity of damage by preventing inflammation and fibrosis. Apart from the beneficial effect on kidney disease itself, BMP-7 improves important complications of chronic renal impairment such as renal osteodystrophy and vascular calcification.
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Affiliation(s)
- Petra Simic
- Laboratory for Mineralized Tissues, Department of Anatomy, School of Medicine, University of Zagreb, Salata 11, 10 000 Zagreb, Croatia
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27
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Yanagita M. BMP antagonists: Their roles in development and involvement in pathophysiology. Cytokine Growth Factor Rev 2005; 16:309-17. [PMID: 15951218 DOI: 10.1016/j.cytogfr.2005.02.007] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Accepted: 02/21/2005] [Indexed: 01/29/2023]
Abstract
Bone morphogenetic proteins (BMPs) are phylogenetically conserved signaling molecules that belong to the transforming growth factor (TGF)-beta superfamily, and are involved in the cascades of body patterning and morphogenesis. The activities of BMPs are precisely regulated by certain classes of molecules that are recently recognized as BMP antagonists. BMP antagonists function through direct association with BMPs, thus prohibiting BMPs from binding their cognate receptors. In this review, the classification and functions of BMP antagonists will be discussed, especially focusing on the new family of tissue-specific BMP antagonists composed of uterine sensitization-associated gene 1 (USAG-1) and sclerostin.
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Affiliation(s)
- Motoko Yanagita
- COE Formation for Genomic Analysis of Disease Model Animals with Multiple Genetic Alterations, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.
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28
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Lin J, Patel SR, Cheng X, Cho EA, Levitan I, Ullenbruch M, Phan SH, Park JM, Dressler GR. Kielin/chordin-like protein, a novel enhancer of BMP signaling, attenuates renal fibrotic disease. Nat Med 2005; 11:387-93. [PMID: 15793581 DOI: 10.1038/nm1217] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Accepted: 01/31/2005] [Indexed: 01/04/2023]
Abstract
The bone morphogenetic proteins (BMPs) profoundly affect embryonic development, differentiation and disease. BMP signaling is suppressed by cysteine-rich domain proteins, such as chordin, that sequester ligands from the BMP receptor. We describe a novel protein, KCP, with 18 cysteine-rich domains. Unlike chordin, KCP enhances BMP signaling in a paracrine manner. Smad1-dependent transcription and phosphorylated Smad1 (P-Smad1) levels are increased, as KCP binds to BMP7 and enhances binding to the type I receptor. In vivo, Kcp(-/-) mice are viable and fertile. Because BMPs have a pivotal role in renal disease, we examined the phenotype of Kcp(-/-) mice in two different models of renal injury. Kcp(-/-) animals show reduced levels of P-Smad1, are more susceptible to developing renal interstitial fibrosis, are more sensitive to tubular injury and show substantial pathology after recovery. The data indicate an important role for KCP in attenuating the pathology of renal fibrotic disease.
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Affiliation(s)
- Jingmei Lin
- Department of Pathology, University of Michigan, 1301 Catherine Street, Ann Arbor, Michigan 48109, USA
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29
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Zeisberg M, Müller GA, Kalluri R. Are there endogenous molecules that protect kidneys from injury? The case for bone morphogenic protein-7 (BMP-7). Nephrol Dial Transplant 2004; 19:759-61. [PMID: 15031324 DOI: 10.1093/ndt/gfh060] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Abstract
OBJECTIVES Despite technological advances in renal replacement therapy over the past few years, acute renal failure in the intensive care unit remains associated with high morbidity and mortality rates. In this article I review recent research aimed at elucidating mechanisms of renal recovery from acute injury. DESIGN Review of the literature. CONCLUSIONS A number of peptide growth hormones are reviewed, including epidermal growth factor, insulin-like growth factor-1, thyroxine, hepatocyte growth factor, and bone morphogenetic protein-7 promote renal regeneration in model systems. Unfortunately, despite promising studies in animal models of toxin and ischemia-induced acute tubular necrosis, human studies have not shown any clinical benefit. However, several of these molecules have not been studied in clinical trials. Existing pharmacologic strategies have a limited role in renal recovery. Finally, several recent studies have focused on the effects of renal replacement therapy on renal recovery, but additional studies are needed to confirm and extend these results.
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Affiliation(s)
- Kathleen D Liu
- Department of Medicine, Unicversity of California, San Francisco, USA
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31
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Evans RA, Tian YC, Steadman R, Phillips AO. TGF-beta1-mediated fibroblast-myofibroblast terminal differentiation-the role of Smad proteins. Exp Cell Res 2003; 282:90-100. [PMID: 12531695 DOI: 10.1016/s0014-4827(02)00015-0] [Citation(s) in RCA: 300] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is now clear that resident myofibroblasts play a central role in the mediation of tissue fibrosis. The aim of the work outlined in this study is to increase our understanding of the mechanisms which drive the phenotypic and functional changes associated with the differentiation process. We have used an in vitro model of transforming growth factor-beta1 (TGF-beta1)-induced pulmonary fibroblast-myofibroblast differentiation to examine the role of the TGF-beta1 Smad protein signaling intermediates, in alterations of fibroblast phenotype and function associated with terminal differentiation. TGF-beta1 induced marked alteration in cell phenotype, such that cells resembled "epithelioid-postmitotic fibroblasts." This was associated with marked reorganization of the actin cytoskeleton and upregulation of alphaSMA gene expression. TGF-beta1 stimulation also induced alphaSMA protein expression with increased incorporation of alphaSMA into stress fibers. Following stimulation with TGF-beta1, subsequent addition of serum-free medium did not reverse TGF-beta1-induced morphological change, suggesting that TGF-beta1 induced a relatively stable alteration in fibroblast cell phenotype. Functionally, these phenotypic changes were associated with induction of type I, type III, and type IV collagen gene expression and an increase in the concentrations of the respective collagens in the cell culture supernatant. The role of Smad proteins in terminal differentiation of fibroblasts was examined by transfection of cells, with expression vectors for the TGFbeta1 receptor-regulated Smads (R-Smads) or the co-Smad, Smad 4. Transfection with Smad2 but not Smad3 resulted in TGF-beta1 independent alteration in fibroblast cell phenotype, up-regulation of alphaSMA mRNA and reorganization of the actin cytoskeleton. Transfection with Smad4 also induced alteration in cell phenotype, although this was not as pronounced as the effect of overexpression of Smad2. Overexpression of the Smad2, Smad3, or Smad4 proteins was associated with increased production of all collagen types. The study suggests that the phenotypic and functional changes associated with TGF-beta1-induced fibroblast terminal differentiation are differentially regulated by Smad proteins.
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Affiliation(s)
- Rachel Anna Evans
- Institute of Nephrology, University of Wales College of Medicine, Heath Park, Cardiff, UK
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32
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Morrissey J, Hruska K, Guo G, Wang S, Chen Q, Klahr S. Bone Morphogenetic Protein-7 Improves Renal Fibrosis and Accelerates the Return of Renal Function. J Am Soc Nephrol 2002. [DOI: 10.1681/asn.v13suppl_1s14] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
ABSTRACT. A prevention protocol has demonstrated that bone morphogenetic protein-7 (BMP-7) blunted the development of fibrosis in a rat model of unilateral ureteral obstruction. This prevention protocol also preserved, to an extent, renal function. The prevention protocol was extended and a treatment protocol used to examine if BMP-7 was beneficial at limiting fibrosis of the kidney when the BMP-7 was administered during the progression of fibrotic disease. Animals were distributed into four groups. Group 1 received vehicle, group 2 received enalapril (12.5 mg/kg body wt per d), group 3 received BMP-7 (50 or 300 μg/kg), and group 4 received both the enalapril and the high dose of BMP-7. Rats underwent reversible unilateral ureteral obstruction for 3 d, after which the obstruction was relieved. In the treatment protocol, 300 μg/kg BMP-7 was given after the release of obstruction. Seven days after release of the obstruction and the onset of treatment glomerular filtration rate (GFR), renal blood flow, and various histologic indexes of fibrosis were determined. On a consistent basis, BMP-7 treatment alone was found to be slightly but significantly (P < 0.04 to 0.007) better than enalapril alone or in combination with enalapril at decreasing interstitial volume or tubule atrophy. BMP-7 treatment was slightly but not significantly better (P < 0.09) than enalapril at restoring GFR in the prevention protocol. Treatment with BMP-7 significantly boosted GFR (P < 0.01) above that seen with vehicle treatment. These results suggest that BMP-7 treatment is capable of blunting the progression of fibrotic disease and of decreasing interstitial volume. Importantly, a return of renal function is accelerated by BMP-7 treatment. These results suggest that administration of BMP-7 may be an effective treatment to restore or preserve renal histology and renal function in this experimental model of renal disease.
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Gould SE, Day M, Jones SS, Dorai H. BMP-7 regulates chemokine, cytokine, and hemodynamic gene expression in proximal tubule cells. Kidney Int 2002; 61:51-60. [PMID: 11786084 DOI: 10.1046/j.1523-1755.2002.00103.x] [Citation(s) in RCA: 178] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Proximal tubule epithelial cells (PTEC) play a central role in the response of the kidney to insult by virtue of their production of chemokines and cytokines that signal an inflammatory response. Bone morphogenic protein-7 (BMP-7/OP-1), a member of the transforming growth factor-beta (TGF-beta) superfamily, has previously been demonstrated to reduce macrophage infiltration and tissue damage in animal models of acute and chronic renal failure. The present study was designed to define the molecular mechanism of BMP-7 action in human PTEC. METHODS Expression of BMP-7 in the adult mouse kidney was determined indirectly through X-gal staining of heterozygous BMP-7/lacZ mice in combination with cell-type specific markers. Primary human PTEC were cultured in the presence of the pro-inflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha), with and without BMP-7. RNA isolated from these two populations was then used to identify differentially regulated genes via gene-array analysis. Modulation of potential target genes was subsequently confirmed through ELISA and/or quantitative PCR. RESULTS Expression from the BMP-7/lacZ transgene was detected in the collecting duct, thick ascending limb, distal convoluted tubule, and podocytes within glomeruli. No expression was detected within PTEC; however, these cells were found to express mRNA for BMP receptors including, ActR-I, BMPR-IA, ActR-II, ActR-IIB, and BMPR-II. BMP-7 significantly reduced TNF-alpha stimulated increases in mRNA for the pro-inflammatory genes, interleukin-6 (IL-6) and interleukin-1beta (IL-1beta), and the chemoattractants monocyte chemotactic protein-1 (MCP-1) and interleukin-8 (IL-8) in primary human PTEC. In addition, BMP-7 also reduced the expression of mRNA for endothelin-2 (ET-2), a vasoconstrictor, and increased the expression of mRNA for heme oxygenase-1 (HO-1), a vasodilator, although the latter was not statistically significant. In experiments designed to examine MCP-1 and IL-6 protein levels in response to additional TGF-beta superfamily members, TGF-beta1 was unable to mimic the effects of BMP-7 in reducing IL-6 production. However, the closely related BMP-6 exhibited similar properties to those of BMP-7. Each of the factors reduced MCP-1 expression. CONCLUSIONS BMP-7 represses the basal and TNF-alpha-stimulated expression of the pro-inflammatory cytokines IL-6 and IL-1beta, the chemokines MCP-1 and IL-8, and the vasoconstrictor ET-2 in PTEC. This data are consistent with the in vivo observations that BMP-7 administration in a model of chronic and acute renal failure results in a reduction in the infiltration of macrophages in the renal interstitium. Taken together, these observations suggest that BMP-7 may be a novel therapeutic agent for kidney disorders involving inflammation and ischemic damage of PTEC.
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Maeshima A, Nojima Y, Kojima I. The role of the activin-follistatin system in the developmental and regeneration processes of the kidney. Cytokine Growth Factor Rev 2001; 12:289-98. [PMID: 11544099 DOI: 10.1016/s1359-6101(01)00010-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Regeneration processes in many tissues are modulated by various factors, which are involved in their organogenesis. Activin A, a member of the TGF-beta superfamily, inhibits branching tubulogenesis of the kidney in organ culture system as well as in in vitro tubulogenesis model. On the other hand, follistatin, an antagonist activin A, reverses the effect of activin A on kidney development, induces branching tubulogenesis, and also promotes tubular regeneration after ischemia/reperfusion injury by blocking the action of endogenous activin A. The activin-follistatin system is one of the important regulatory systems modulating developmental and regeneration processes of the kidneys.
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Affiliation(s)
- A Maeshima
- Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, 371-8512, Japan
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Azari K, Doll BA, Sfeir C, Mu Y, Hollinger JO. Therapeutic potential of bone morphogenetic proteins. Expert Opin Investig Drugs 2001; 10:1677-86. [PMID: 11772277 DOI: 10.1517/13543784.10.9.1677] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Recently, there has been substantial progress in the area of bone morphogenetic protein (BMP) research. This review serves as an up-to-date summary of the history of BMPs, the mechanisms of BMP signalling and the role of BMPs in adipose, kidney, liver, bone and nervous system. The potential of BMPs as therapeutic agents will also be discussed.
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Affiliation(s)
- K Azari
- Bone Tissue Engineering Center, Carnegie Mellon University, 125 Smith Hall, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA.
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Hruska KA, Guo G, Wozniak M, Martin D, Miller S, Liapis H, Loveday K, Klahr S, Sampath TK, Morrissey J. Osteogenic protein-1 prevents renal fibrogenesis associated with ureteral obstruction. Am J Physiol Renal Physiol 2000; 279:F130-43. [PMID: 10894795 DOI: 10.1152/ajprenal.2000.279.1.f130] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Unilateral ureteral obstruction (UUO) is a model of renal injury characterized by progressive tubulointerstitial fibrosis and renal damage, while relatively sparing the glomerulus and not producing hypertension or abnormalities in lipid metabolism. Tubulointerstitial fibrosis is a major component of several kidney diseases associated with the progression to end-stage renal failure. Here we report that when a critical renal developmental morphogen, osteogenic protein-1 (OP-1; 100 or 300 microg/kg body wt), is administered at the time of UUO and every other day thereafter, interstitial inflammation and fibrogenesis are prevented, leading to preservation of renal function during the first 5 days after obstruction. Compared with angiotensin-converting enzyme inhibition with enalapril treatment, OP-1 was more effective in preventing tubulointerstitial fibrosis and in preserving renal function. The mechanism of OP-1- induced renal protection was associated with prevention of tubular atrophy, an effect not shared with enalapril, and was related to preservation of tubular epithelial integrity. OP-1 blocked the stimulation of epithelial cell apoptosis produced by UUO, which promoted maintenance of tubular epithelial integrity. OP-1 preserved renal blood flow (RBF) during UUO, but enalapril also stimulated RBF. Thus OP-1 treatment inhibited tubular epithelial disruption stimulated by the renal injury of UUO, preventing tubular atrophy and diminishing the activation of tubulointerstitial inflammation and fibrosis and preserving renal function.
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Affiliation(s)
- K A Hruska
- Renal Division, Departments of Medicine, Barnes-Jewish Hospital at Washington University, St. Louis, Missouri 63110, USA.
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Simon M, Maresh JG, Harris SE, Hernandez JD, Arar M, Olson MS, Abboud HE. Expression of bone morphogenetic protein-7 mRNA in normal and ischemic adult rat kidney. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 276:F382-9. [PMID: 10070161 DOI: 10.1152/ajprenal.1999.276.3.f382] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BMP-7, a member of the bone morphogenic protein subfamily (BMPs) of the transforming growth factor-beta superfamily of secreted growth factors, is abundantly expressed in the fetal kidney. The precise role of this protein in renal physiology or pathology is unknown. A cDNA that encodes rat BMP-7 was cloned and used as a probe to localize BMP-7 mRNA expression by in situ hybridization in the adult rat kidney. The highest expression of BMP-7 mRNA could be seen in tubules of the outer medulla. In glomeruli, a few cells, mainly located at the periphery of the glomerular tuft, showed specific and strong signals. Also, high BMP-7 mRNA expression could be localized to the adventitia of renal arteries, as well as to the epithelial cell layer of the renal pelvis and the ureter. Preliminary evidence suggests that BMP-7 enhances recovery when infused into rats with ischemia-induced acute renal failure. We examined BMP-7 mRNA expression in kidneys with acute renal failure induced by unilateral renal artery clamping. BMP-7 mRNA abundance as analyzed by solution hybridization was reduced in ischemic kidneys after 6 and 16 h of reperfusion compared with the contralateral kidney. In situ hybridization in ischemic kidneys showed a marked decrease of BMP-7 mRNA in the outer medulla and in glomeruli. Utilizing rat metanephric mesenchymal cells in culture, we also demonstrate that BMP-7 induces epithelial cell differentiation. Taken together, these data suggest that BMP-7 is important in both stimulating and maintaining a healthy differentiated epithelial cell phenotype.
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Affiliation(s)
- M Simon
- Division of Nephrology, University of Texas Health Science Center, and Audie L. Murphy Memorial Veterans Affairs Hospital San Antonio, Texas 78284, USA
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