Maria Mirotsou

Duke University Medical Center, Durham, North Carolina, United States

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Publications (26)156.21 Total impact

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    ABSTRACT: Wnt signaling has recently emerged as an important regulator of cardiac progenitor cell proliferation and differentiation, but the exact mechanisms by which Wnt signaling modulates these effects are not known. Understanding these mechanisms is essential for advancing our knowledge of cardiac progenitor cell biology and applying this knowledge to enhance cardiac therapy. Here, we explored the effects of Sfrp2, a canonical Wnt inhibitor, in adult cardiac progenitor cell (CPC) differentiation and investigated the molecular mechanisms involved. Our data show that Sfrp2 treatment can promote differentiation of CPCs after ischemia-reperfusion injury. Treatment of CPCs with Sfrp2 inhibited CPC proliferation and primed them for cardiac differentiation. Sfrp2 binding to Wnt6 and inhibition of Wnt6 canonical pathway was essential for the inhibition of CPC proliferation. This inhibition of Wnt6 canonical signaling by Sfrp2 was important for activation of the non-canonical Wnt/Planar Cell Polarity (PCP) pathway through JNK, which in turn induced expression of cardiac transcription factors and CPC differentiation. Taken together, these results demonstrate a novel role of Sfrp2 and Wnt6 in regulating the dynamic process of CPC proliferation and differentiation, as well as providing new insights into the mechanisms of Wnt signaling in cardiac differentiation. Copyright © 2015. Published by Elsevier Ltd.
    Journal of Molecular and Cellular Cardiology 06/2015; 85. DOI:10.1016/j.yjmcc.2015.06.003 · 5.22 Impact Factor
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    ABSTRACT: The human heart has a limited capacity to regenerate lost or damaged cardiomyocytes after cardiac insult. Instead, myocardial injury is characterized by extensive cardiac remodeling by fibroblasts, resulting in the eventual deterioration of cardiac structure and function. Cardiac function would be improved if these fibroblasts could be converted into cardiomyocytes. MicroRNAs (miRNAs), small noncoding RNAs that promote mRNA degradation and inhibit mRNA translation, have been shown to be important in cardiac development. Using this information, various researchers have used miRNAs to promote the formation of cardiomyocytes through several approaches. Several miRNAs acting in combination promote the direct conversion of cardiac fibroblasts into cardiomyocytes. Moreover, several miRNAs have been identified that aid the formation of inducible pluripotent stem cells and miRNAs also induce these cells to adopt a cardiac fate. MiRNAs have also been implicated in resident cardiac progenitor cell differentiation. In this review, we discuss the current literature as it pertains to these processes, as well as discussing the therapeutic implications of these findings. © 2015 American Heart Association, Inc.
    Circulation Research 05/2015; 116(10):1700-1711. DOI:10.1161/CIRCRESAHA.116.304377 · 11.09 Impact Factor
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    ABSTRACT: Despite the importance of juxtaglomerular cell recruitment in the pathophysiology of cardiovascular diseases, the mechanisms that underlie renin production under conditions of chronic stimulation remain elusive. We have previously shown that CD44+ mesenchymal-like cells (CD44+ cells) exist in the adult kidney. Under chronic sodium deprivation, these cells are recruited to the juxtaglomerular area and differentiate to new renin-expressing cells. Given the proximity of macula densa to the juxtaglomerular area and the importance of macula densa released prostanoids in renin synthesis and release, we hypothesized that chronic sodium deprivation induces macula densa release of prostanoids, stimulating renal CD44+ cell activation and differentiation. CD44+ cells were isolated from adult kidneys and cocultured with the macula densa cell line, MMDD1, in normal or low-sodium medium. Low sodium stimulated prostaglandin E2 production by MMDD1 and induced migration of CD44+ cells. These effects were inhibited by addition of a cyclooxygenase 2 inhibitor (NS398) or an E-prostanoid receptor 4 antagonist (AH23848) to MMDD1 or CD44+ cells, respectively. Addition of prostaglandin E2 to CD44+ cells increased cell migration and induced renin expression. In vivo activation of renal CD44+ cells during juxtaglomerular recruitment was attenuated in wild-type mice subjected to salt restriction in the presence of cyclooxygenase 2 inhibitor rofecoxib. Similar results were observed in E-prostanoid receptor 4 knockout mice subjected to salt restriction. These results show that the prostaglandin E2/E-prostanoid receptor 4 pathway plays a key role in the activation of renal CD44+ mesenchymal stromal cell-like cells during conditions of juxtaglomerular recruitment; highlighting the importance of this pathway as a key regulatory mechanism of juxtaglomerular recruitment. © 2015 American Heart Association, Inc.
    Hypertension 03/2015; 65(5). DOI:10.1161/HYPERTENSIONAHA.114.04611 · 7.63 Impact Factor
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    ABSTRACT: Rationale: A major goal for the treatment of heart tissue damaged by cardiac injury is to develop strategies for restoring healthy heart muscle through the regeneration and repair of damaged myocardium. We recently demonstrated that administration of a specific combination of micro-RNAs (miR combo) into the infarcted myocardium leads to direct in vivo reprogramming of non-cardiac myocytes to cardiac myocytes. However, the biologic and functional consequences of such reprogramming are not yet known. Objective: The aim of this study was to determine whether non-cardiac myocytes directly reprogrammed using miRNAs in vivo develop into mature functional cardiac myocytes in situ, and whether reprogramming leads to improvement of cardiac function. Methods and Results: We subjected FSP1-Cre mice/tdTomato mice to cardiac injury by permanent ligation of the left anterior descending coronary artery (LAD) and injected lentiviruses encoding miR combo or a control nontargeting miRNA. miR combo significantly increased the number of reprogramming events in vivo. Five-to-six weeks following injury, morphological and physiological properties of tdTomato(-) and tdTomato(+) cardiac myocyte-like cells were analyzed ex vivo. tdTomato(+) cells expressed cardiac myocyte markers, sarcomeric organization, excitation-contraction coupling, and action potentials characteristic of mature ventricular cardiac myocytes (tdTomato(-) cells). Reprogramming was associated with improvement of cardiac function, as analyzed by serial echocardiography. There was a time delayed and progressive improvement in fractional shortening and other measures of ventricular function, indicating that miR combo promotes functional recovery of damaged myocardium. Conclusions: The findings from this study further validate the potential utility of miRNA-mediated reprogramming as a therapeutic approach to promote cardiac regeneration following myocardial injury.
    Circulation Research 10/2014; 116(3). DOI:10.1161/CIRCRESAHA.116.304510 · 11.09 Impact Factor
  • Sophie Dal-Pra · Maria Mirotsou
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    ABSTRACT: Reconstitution of cardiac muscle as well as blood vessels to provide sufficient oxygenation and nutrients to the myocardium is an important component of any therapeutic approach for cardiac repair after injury. Recent reports of reprogramming somatic cells directly to cells of another lineage raised the possibility of using cell reprogramming for cardiac regenerative therapy. Here, we provide an overview of the current reprogramming strategies to generate cardiomyocytes (CMs), endothelial cells (ECs) and smooth muscle cells (SMCs), and the implications of these methods for cardiac regeneration. We also discuss the challenges and limitations that need to be addressed for the development of future therapies.
    Current Treatment Options in Cardiovascular Medicine 08/2014; 16(8):327. DOI:10.1007/s11936-014-0327-0
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    ABSTRACT: The renin-angiotensin system has powerful effects in control of the blood pressure and sodium homeostasis. These actions are coordinated through integrated actions in the kidney, cardiovascular system and the central nervous system. Along with its impact on blood pressure, the renin-angiotensin system also influences a range of processes from inflammation and immune responses to longevity. Here, we review the actions of the "classical" renin-angiotensin system, whereby the substrate protein angiotensinogen is processed in a two-step reaction by renin and angiotensin converting enzyme, resulting in the sequential generation of angiotensin I and angiotensin II, the major biologically active renin-angiotensin system peptide, which exerts its actions via type 1 and type 2 angiotensin receptors. In recent years, several new enzymes, peptides, and receptors related to the renin-angiotensin system have been identified, manifesting a complexity that was previously unappreciated. While the functions of these alternative pathways will be reviewed elsewhere in this journal, our focus here is on the physiological role of components of the "classical" renin-angiotensin system, with an emphasis on new developments and modern concepts. © 2014 American Physiological Society. Compr Physiol 4:1201-1228, 2014.
    Comprehensive Physiology 07/2014; 4(3):1201-28. DOI:10.1002/cphy.c130040 · 4.74 Impact Factor
  • Tilanthi Jayawardena · Maria Mirotsou · Victor J Dzau
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    ABSTRACT: The therapeutic administration of microRNAs represents an innovative reprogramming strategy with which to advance cardiac regeneration and personalized medicine. Recently, a distinct set of microRNAs was found capable of converting murine fibroblasts to cardiomyocyte-like cells in vitro. Further treatment with JAK inhibitor I significantly enhanced the efficiency of the microRNA-mediated reprogramming (Jayawardena et al., Circ Res 110(11):1465-1473, 2012). This novel technique serves as an initial tool for switching the cell fate of cardiac fibroblasts toward the cardiomyocyte lineage using microRNAs. As the budding field of reprogramming biology develops, we hope that a thorough examination of the chemical, physical, and temporal parameters determining reprogramming efficiency and maturation will enable a better understanding of the mechanisms governing cardiac cell fate and provide new approaches for drug discovery and therapy for cardiovascular diseases.
    Methods in molecular biology (Clifton, N.J.) 01/2014; 1150:263-72. DOI:10.1007/978-1-4939-0512-6_18 · 1.29 Impact Factor
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    ABSTRACT: Despite advances in the treatment of acute tissue ischemia significant challenges remain in effective cytoprotection from ischemic cell death. It has been documented that injected stem cells, such as mesenchymal stem cells (MSCs), can confer protection to ischemic tissue through the release of paracrine factors. The study of these factors is essential for understanding tissue repair and the development of new therapeutic approaches for regenerative medicine. We have recently shown that a novel factor secreted by MSCs, which we called HASF (Hypoxia and Akt induced Stem cell Factor), promotes cardiomyocyte proliferation. In this study we show that HASF has a cytoprotective effect on ischemia induced cardiomyocyte death. We assessed whether HASF could potentially be used as a therapeutic agent to prevent the damage associated with myocardial infarction. In vitro treatment of cardiomyocytes with HASF protein resulted in decreased apoptosis; TUNEL positive nuclei were fewer in number, and caspase activation and mitochondrial pore opening were inhibited. Purified HASF protein was injected into the heart immediately following myocardial infarction. Heart function was found to be comparable to sham operated animals one month following injury and fibrosis was significantly reduced. In vivo and in vitro HASF activated protein kinase C ε (PKCε). Inhibition of PKCε blocked the HASF effect on apoptosis. Furthermore, the beneficial effects of HASF were lost in mice lacking PKCε. Collectively these results identify HASF as a protein of significant therapeutic potential, acting in part through PKCε.
    Journal of Molecular and Cellular Cardiology 11/2013; 66. DOI:10.1016/j.yjmcc.2013.11.010 · 5.22 Impact Factor
  • Marcela Herrera · Maria Mirotsou
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    ABSTRACT: Renal damage resulting from acute and chronic kidney injury poses an important problem to public health. Currently patients with end stage renal disease rely solely on kidney transplantation or dialysis for survival. Emerging therapies aiming to prevent and reverse kidney damage are thus in urgent need. Although the kidney was initially thought to lack the capacity for self-repair, several studies have indicated that this might not be the case; Progenitor and stem cells appear to play important roles in kidney repair under various pathological conditions. In this review we summarize recent findings on the role of progenitor/stem cells on kidney repair as well as discuss their potential as a therapeutic approach for kidney diseases.
    AJP Renal Physiology 11/2013; 306(1). DOI:10.1152/ajprenal.00238.2013 · 4.42 Impact Factor
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    ABSTRACT: Mesenchymal stem cells (MSCs) transplanted into injured myocardium promote repair through paracrine mechanisms. We have previously shown that MSCs overexpressing AKT1 (Akt-MSCs) exhibit enhanced properties for cardiac repair. In this study, we investigated the relevance of Abi3bp towards MSC biology. Abi3bp formed extracellular deposits with expression controlled by Akt1 and ubiquitin-mediated degradation. Abi3bp knockdown/knockout stabilized focal adhesions and promoted stress-fiber formation. Furthermore, MSCs from Abi3bp knockout mice displayed severe deficiencies in osteogenic and adipogenic differentiation. Knockout or stable knockdown of Abi3bp increased MSC and Akt-MSC proliferation, promoting S-phase entry via cyclin-d1, ERK1/2 and Src. Upon Abi3bp binding to integrin-β1 Src associated with paxillin which inhibited proliferation. In vivo, Abi3bp knockout increased MSC number and proliferation in bone marrow, lung, and liver. In summary, we have identified a novel extracellular matrix protein necessary for the switch from proliferation to differentiation in MSCs.
    Stem Cells 08/2013; 31(8). DOI:10.1002/stem.1416 · 7.70 Impact Factor
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    ABSTRACT: Rationale: The regenerative capacity of the heart is markedly diminished shortly after birth coinciding with overall withdrawal of cardiomyocytes from cell cycle. Consequently, the adult mammalian heart has limited capacity to regenerate after injury. The discovery of factors that can induce cardiomyocyte proliferation is therefore of high interest and has been the focus of extensive investigation over the past years. Objective: We have recently identified C3orf58 as a novel Hypoxia and Akt induced Stem cell Factor (HASF) secreted from mesenchymal stem cells that can promote cardiac repair through cytoprotective mechanisms. Here, we tested the hypothesis that HASF can also contribute to cardiac regeneration by stimulating cardiomyocyte division and proliferation. Methods and Results: Neonatal ventricular cardiomyocytes were stimulated in culture for seven days with purified recombinant HASF protein. Compared to control untreated cells, HASF-treated neonatal cardiomyocytes exhibited 60% increase in DNA synthesis as measured by BrdU incorporation. These results were confirmed by immunofluorescence confocal microscopy showing a 50-100% increase in the number of cardiomyocytes in the mitotic and cytokinesis phases. Importantly, in vivo cardiac overexpression of HASF in a transgenic mouse model resulted in enhanced level of DNA synthesis and cytokinesis in neonatal and adult cardiomyocytes. These proliferative effects were modulated by a PI3K-AKT-CDK7 pathway as revealed by the use of PI3K pathway specific inhibitors and silencing of the Cdk7 gene. Conclusions: Our studies support the hypothesis that HASF induces cardiomyocyte proliferation via a PI3K-AKT-CDK7 pathway. The implications of this finding may be significant for cardiac regeneration biology and therapeutics.
    Circulation Research 06/2013; 113(4). DOI:10.1161/CIRCRESAHA.113.301075 · 11.09 Impact Factor
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    ABSTRACT: The renin-angiotensin-aldosterone system (RAAS) regulates BP and salt-volume homeostasis. Juxtaglomerular (JG) cells synthesize and release renin, which is the first and rate-limiting step in the RAAS. Intense pathologic stresses cause a dramatic increase in the number of renin-producing cells in the kidney, termed JG cell recruitment, but how this occurs is not fully understood. Here, we isolated renal CD44(+) mesenchymal stem cell (MSC)-like cells and found that they differentiated into JG-like renin-expressing cells both in vitro and in vivo. Sodium depletion and captopril led to activation and differentiation of these cells into renin-expressing cells in the adult kidney. In summary, CD44(+) MSC-like cells exist in the adult kidney and can differentiate into JG-like renin-producing cells under conditions that promote JG cell recruitment.
    Journal of the American Society of Nephrology 06/2013; DOI:10.1681/ASN.2012060596 · 9.47 Impact Factor
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    ABSTRACT: Rationale: Regeneration of damaged cardiac tissue after injury presents a daunting challenge in cardiovascular medicine. Recent developments in reprogramming of somatic cells directly to cells of other lineages have raised the possibility of using this approach for cardiac regenerative therapy. Our group recently demonstrated successful miRNA mediated cardiac reprogramming in vitro and in vivo using a combination of miRNAs 1, 133, 206 and 499. Although, the molecular mechanisms underlying miRNA mediated fibroblast reprogramming to cardiomyocytes are yet unknown, accumulating evidence suggest that reprogramming acts through distinct phases and that histone modifications play an important role in these processes. Objective: Identify key genes involved in initiating miRNA mediated reprogramming via histone modifications. Methods and Results: For this, we analyzed the expression levels of 81 different genes involved in chromatin modification 4 days after miRNA transfection using PCR arrays. This analysis revealed that 6 of the 81 tested genes showed differential gene expression (-1.5-fold and p <0.02). JAK inhibitor-1 treatment, known for increasing reprogramming efficiency, further enhanced gene expression changes in 5 of these 6 genes. Setdb2, an H3K9 methyltransferase, was one of the most down-regulated targets 4 days after miRNA transfection (-1.4 fold, p<0.001). This effect was enhanced further when miRNAs were combined with the JAK inhibitor-1 (-2.6 fold, p<0.001). Silencing of Setdb2 using siRNAs further accentuated miRNA cardiac reprogramming as measured by cardiac transcription factor expression at 3 days and 6 days post treatment. Similar trends were observed by FACS analysis detecting increased percentage of αMHC-positive cells in siRNA treated fibroblasts compared to control treated only with the miRNA combination. Interestingly, our data showed that Setdb2 silencing alone was sufficient to initiate cardiac reprogramming, suggesting that Setdb2 might play a crucial role in defining cardiac cell fate. Conclusion: In conclusion our results indicate that Setdb2 down-regulation plays an important role in the direct reprogramming of fibroblasts to cardiomyocyte-like cells.
    BCVS 2013, Las Vegas, NV; 05/2013
  • Karthikeyan Ardhanareeswaran · Maria Mirotsou
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    ABSTRACT: Over the past few years, new insights have been added to the study of stem cells in the adult lung. The exploration of endogenous lung progenitors as well as the study of exogenously delivered stem cell populations holds promise for advancing our understanding of the biology of lung repair mechanisms. Moreover, it opens new possibilities for the use of stem cell therapy for the development of regenerative medicine approaches for the treatment of lung disease. Here, we discuss the main types of lung epithelial progenitor populations; the potential of endothelial progenitors, mesenchymal stem cells and embryonic stem cells for lung therapy, as well as summarize the cellular mechanisms involved.
    Respiration 02/2013; 85(2):89-95. DOI:10.1159/000346500 · 2.92 Impact Factor
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    ABSTRACT: Introduction: Direct conversion of injured heart tissue to functional cardiomyocyte in situ represents an exciting approach for cardiac regeneration. We have recently shown that the combination of miRNAs 1, 133, 208 and 499 were able to reprogram mouse cardiac fibroblasts in vitro and in vivo to cardiomyocyte like cells. Here, we investigate the mechanisms involved in these processes as well as explore the feasibility of this approach in reprogramming human fibroblasts towards the cardiomyocyte fate. Methods and Results: Expression analysis miRNA transfected fibroblast demonstrated rapid induction (1-2 days) of primitive cardiac mesodermal marker Mesp2 but no change in the pluripotency markers Oct4 and Nanog suggesting that reprogramming results from a direct switch to cardiomyocyte progenitor state. Further microarray analysis using the Affymetrix GeneChip Mouse Genome 430 2.0 Array revealed that 1200 genes were differentially regulated between miRNA treated and control cardiac fibroblasts (P<0.01). This list was highly enriched for transcription factors and chromatin remodeling modulators (125 genes). HDAC2, a histone deacetylase that was recently associated with reprogramming of fibroblasts to iPS cells, was the only histone deacetylase that showed significant change upon treatment with the miRNA combination (decreased nearly 95%). These results were corroborated by qRT-PCR. Clustering analysis consistently altered expression of a sub-cluster of 5 genes (with functional relevance to HDAC2, further highlighting the potential importance of HDAC in modulating the miRNA effects directly and/or indirectly. Finally, to explore the feasibility of the miRNA approach to reprogram human fibroblasts, we transiently transfected BJ cells with the microRNA combination. Our preliminary results indicate that combination microRNA treatment of human fibroblasts results in the upregulation of early cardiomyocyte markers such as Mef2. Conclusion: Our data provide insights into the mechanisms of microRNA mediated cardiac reprogramming, indicating direct conversion and the potential role of epigenetic modulation.
    American Heart Association (AHA) Scientific Sessions, Los Angeles; 11/2012
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    ABSTRACT: Repopulation of the injured heart with new, functional cardiomyocytes remains a daunting challenge for cardiac regenerative medicine. An ideal therapeutic approach would involve an effective method at achieving direct conversion of injured areas to functional tissue in situ. The aim of this study was to develop a strategy that identified and evaluated the potential of specific micro (mi)RNAs capable of inducing reprogramming of cardiac fibroblasts directly to cardiomyocytes in vitro and in vivo. Using a combinatorial strategy, we identified a combination of miRNAs 1, 133, 208, and 499 capable of inducing direct cellular reprogramming of fibroblasts to cardiomyocyte-like cells in vitro. Detailed studies of the reprogrammed cells demonstrated that a single transient transfection of the miRNAs can direct a switch in cell fate as documented by expression of mature cardiomyocyte markers, sarcomeric organization, and exhibition of spontaneous calcium flux characteristic of a cardiomyocyte-like phenotype. Interestingly, we also found that miRNA-mediated reprogramming was enhanced 10-fold on JAK inhibitor I treatment. Importantly, administration of miRNAs into ischemic mouse myocardium resulted in evidence of direct conversion of cardiac fibroblasts to cardiomyocytes in situ. Genetic tracing analysis using Fsp1Cre-traced fibroblasts from both cardiac and noncardiac cell sources strongly suggests that induced cells are most likely of fibroblastic origin. The findings from this study provide proof-of-concept that miRNAs have the capability of directly converting fibroblasts to a cardiomyocyte-like phenotype in vitro. Also of significance is that this is the first report of direct cardiac reprogramming in vivo. Our approach may have broad and important implications for therapeutic tissue regeneration in general.
    Circulation Research 04/2012; 110(11):1465-73. DOI:10.1161/CIRCRESAHA.112.269035 · 11.09 Impact Factor
  • Scientific Sessions of High Blood Pressure Research; 11/2011
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    ABSTRACT: Stem cells play an important role in restoring cardiac function in the damaged heart. In order to mediate repair, stem cells need to replace injured tissue by differentiating into specialized cardiac cell lineages and/or manipulating the cell and molecular mechanisms governing repair. Despite early reports describing engraftment and successful regeneration of cardiac tissue in animal models of heart failure, these events appear to be infrequent and yield too few new cardiomyocytes to account for the degree of improved cardiac function observed. Instead, mounting evidence suggests that stem cell mediated repair takes place via the release of paracrine factors into the surrounding tissue that subsequently direct a number of restorative processes including myocardial protection, neovascularization, cardiac remodeling, and differentiation. The potential for diverse stem cell populations to moderate many of the same processes as well as key paracrine factors and molecular pathways involved in stem cell-mediated cardiac repair will be discussed in this review. This article is part of a special issue entitled, "Cardiovascular Stem Cells Revisited".
    Journal of Molecular and Cellular Cardiology 02/2011; 50(2):280-9. DOI:10.1016/j.yjmcc.2010.08.005 · 5.22 Impact Factor
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    ABSTRACT: The use of stem cells for tissue regeneration and repair is advancing both at the bench and bedside. Stem cells isolated from bone marrow are currently being tested for their therapeutic potential in a variety of clinical conditions including cardiovascular injury, kidney failure, cancer, and neurological and bone disorders. Despite the advantages, stem cell therapy is still limited by low survival, engraftment, and homing to damage area as well as inefficiencies in differentiating into fully functional tissues. Genetic engineering of mesenchymal stem cells is being explored as a means to circumvent some of these problems. This review presents the current understanding of the use of genetically engineered mesenchymal stem cells in human disease therapy with emphasis on genetic modifications aimed to improve survival, homing, angiogenesis, and heart function after myocardial infarction. Advancements in other disease areas are also discussed.
    Human gene therapy 11/2010; 21(11):1513-26. DOI:10.1089/hum.2010.165 · 3.62 Impact Factor
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    ABSTRACT: Secreted frizzled related protein 2 (Sfrp2) is known as an inhibitor for the Wnt signaling. In recent studies, Sfrp2 has been reported to inhibit the activity of Xenopus homolog of mammalian Tolloid-like 1 metalloproteinase. Bone morphogenic protein 1 (Bmp1)/Tolloid-like metalloproteinase plays a key role in the regulation of collagen biosynthesis and maturation after tissue injury. Here, we showed both endogenous Sfrp2 and Bmp1 protein expressions were up-regulated in rat heart after myocardial infarction (MI). We hypothesize that Sfrp2 could inhibit mammalian Bmp1 activity and, hence, the exogenous administration of Sfrp2 after MI would inhibit the deposition of mature collagen and improve heart function. Using recombinant proteins, we demonstrated that Sfrp2, but not Sfrp1 or Sfrp3, inhibited Bmp1 activity in vitro as measured by a fluorogenic peptide based procollagen C-proteinase activity assay. We also demonstrated that Sfrp2 at high concentration inhibited human and rat type I procollagen processing by Bmp1 in vitro. We further showed that exogenously added Sfrp2 inhibited type I procollagen maturation in primary cardiac fibroblasts. Two days after direct injection into the rat infarcted myocardium, Sfrp2 inhibited MI-induced type I collagen deposition. As early as 2 wk after injection, Sfrp2 significantly reduced left ventricular (LV) fibrosis as shown by trichrome staining. Four weeks after injection, Sfrp2 prevented the anterior wall thinning and significantly improved cardiac function as revealed by histological analysis and echocardiographic measurement. Our study demonstrates Sfrp2 at therapeutic doses can inhibit fibrosis and improve LV function at a later stage after MI.
    Proceedings of the National Academy of Sciences 11/2010; 107(49):21110-5. DOI:10.1073/pnas.1004708107 · 9.81 Impact Factor

Publication Stats

917 Citations
156.21 Total Impact Points

Institutions

  • 2010–2015
    • Duke University Medical Center
      • • Department of Medicine
      • • Division of Cardiology
      Durham, North Carolina, United States
  • 2011–2014
    • Duke University
      • Department of Medicine
      Durham, North Carolina, United States
  • 2003–2006
    • Harvard Medical School
      • Department of Medicine
      Boston, Massachusetts, United States