scholarly journals The Emerging Role of PEDF in Stem Cell Biology

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Mina Elahy ◽  
Swati Baindur-Hudson ◽  
Crispin R. Dass

Encoded by a single gene, PEDF is a 50 kDa glycoprotein that is highly conserved and is widely expressed among many tissues. Most secreted PEDF deposits within the extracellular matrix, with cell-type-specific functions. While traditionally PEDF is known as a strong antiangiogenic factor, more recently, as this paper highlights, PEDF has been linked with stem cell biology, and there is now accumulating evidence demonstrating the effects of PEDF in a variety of stem cells, mainly in supporting stem cell survival and maintaining multipotency.

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Muhammad Nawaz ◽  
Farah Fatima ◽  
Krishna C. Vallabhaneni ◽  
Patrice Penfornis ◽  
Hadi Valadi ◽  
...  

Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs) that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 95-95 ◽  
Author(s):  
Keisuke Ito ◽  
Paolo Sportoletti ◽  
John G Clohessy ◽  
Grisendi Silvia ◽  
Pier Paolo Pandolfi

Abstract Abstract 95 Myelodysplastic syndrome (MDS) is an incurable stem cell disorder characterized by ineffective hematopoiesis and an increased risk of leukemia transformation. Nucleophosmin (NPM) is directly implicated in primitive hematopoiesis, the pathogenesis of hematopoietic malignancies and more recently of MDS. However, little is known regarding the molecular role and function of NPM in MDS pathogenesis and in stem cell biology. Here we present data demonstrating that NPM plays a critical role in the maintenance of hematopoietic stem cells (HSCs) and the transformation of MDS into leukemia. NPM is located on chromosome 5q and is frequently lost in therapy-related and de novo MDS. We have previously shown that Npm1 acts as a haploinsufficient tumor suppressor in the hematopoietic compartment and Npm1+/− mice develop a hematologic syndrome with features of human MDS, including increased susceptibility to leukemogenesis. As HSCs have been demonstrated to be the target of the primary neoplastic event in MDS, a functional analysis of the HSC compartment is essential to understand the molecular mechanisms in MDS pathogenesis. However, the role of NPM in adult hematopoiesis remains largely unknown as Npm1-deficiency leads to embryonic lethality. To investigate NPM function in adult hematopoiesis, we have generated conditional knockout mice of Npm1, using the Cre-loxP system. Analysis of Npm1 conditional mutants crossed with Mx1-Cre transgenic mice reveals that Npm1 plays a crucial role in adult hematopoiesis and ablation of Npm1 in adult HSCs leads to aberrant cycling and followed by apoptosis. Analysis of cell cycle status revealed that HSCs are impaired in their ability to maintain quiescence after Npm1-deletion and are rapidly depleted in vivo as well as in vitro. Competitive reconstitution assay revealed that Npm1 acts cell-autonomously to maintain HSCs. Conditional inactivation of Npm1 leads to an MDS phenotype including a profoundly impaired ability to differentiate into cells of the erythroid lineage, megakaryocyte dyspoiesis and centrosome amplification. Furthermore, Npm1 loss evokes a p53-dependent response and Npm1-deleted HSCs undergo apoptosis in vivo and in vitro. Strikingly, transfer of the Npm1 mutation into a p53-null background rescued the apoptosis of Npm1-ablated HSCs and resulted in accelerated transformation to an aggressive and lethal form of acute myeloid leukemia. Our findings highlight the crucial role of NPM in stem cell biology and identify a new mechanism by which MDS can progress to leukemia. This has important therapeutic implications for de novo MDS as well as therapy-related MDS, which is known to rapidly evolve to leukemia with frequent loss or mutation of TRP53. Disclosures: No relevant conflicts of interest to declare.


2012 ◽  
Vol 27 ◽  
pp. 167-184 ◽  
Author(s):  
Ceren Aksoy ◽  
Feride Severcan

Recent researches have mainly displayed the significant role of stem cells in tissue renewal and homeostasis with their unique capacity to develop different cell types. These findings have clarified the importance of stem cells to improve the effectiveness of any cell therapy for regenerative medicine. Identification of purity and differentiation stages of stem cells are the greatest challenges of stem cell biology and regenerative medicine. The existing methods to carefully monitor and characterize the stem cells have some unwanted effects on the properties of stem cells, and these methods also do not provide real-time information about cellular conditions. These challenges enforce the usage of nondestructive, rapid, sensitive, high quality, label-free, cheep, and innovative chemical monitoring methods. In this context, vibrational spectroscopy provides promissing alternative to get new information into the field of stem cell biology for chemical analysis, quantification, and imaging of stem cells. Raman and infrared spectroscopy and imaging can be used as a new complimentary spectroscopic approaches to gain new insight into stem cell reseaches for future therapeutic and regenerative medicines. In this paper, recent developments in applications of vibrational spectroscopy techniques for stem cell characterization and identification are presented.


2012 ◽  
Vol 90 (3) ◽  
pp. 353-360 ◽  
Author(s):  
Paras Kumar Mishra ◽  
Vishalakshi Chavali ◽  
Naira Metreveli ◽  
Suresh C. Tyagi

The contribution of extracellular matrix (ECM) to stem cell survival and differentiation is unequivocal, and matrix metalloproteinase-9 (MMP9) induces ECM turn over; however, the role of MMP9 in the survival and differentiation of cardiac stem cells is unclear. We hypothesize that ablation of MMP9 enhances the survival and differentiation of cardiac stem cells into cardiomyocytes in diabetics. To test our hypothesis, Ins2+/− Akita, C57 BL/6J, and double knock out (DKO: Ins2+/−/MMP9−/−) mice were used. We created the DKO mice by deleting the MMP9 gene from Ins2+/−. The above 3 groups of mice were genotyped. The activity and expression of MMP9 in the 3 groups were determined by in-gel gelatin zymography, Western blotting, and confocal microscopy. To determine the role of MMP9 in ECM stiffness (fibrosis), we measured collagen deposition in the histological sections of hearts using Masson’s trichrome staining. The role of MMP9 in cardiac stem cell survival and differentiation was determined by co-immunoprecipitation (co-IP) of MMP9 with c-kit (a marker of stem cells) and measuring the level of troponin I (a marker of cardiomyocytes) by confocal microscopy in the 3 groups. Our results revealed that ablation of MMP9 (i) reduces the stiffness of ECM by decreasing collagen accumulation (fibrosis), and (ii) enhances the survival (elevated c-kit level) and differentiation of cardiac stem cells into cardiomyocytes (increased troponin I) in diabetes. We conclude that inhibition of MMP9 ameliorates stem cell survival and their differentiation into cardiomyocytes in diabetes.


2010 ◽  
Vol 138 (5) ◽  
pp. S-499
Author(s):  
Masahiko Tsujii ◽  
Jumpei Kondo ◽  
Tomofumi Akasaka ◽  
Ying Jin ◽  
Yoshito Hayashi ◽  
...  

2021 ◽  
pp. 1-18
Author(s):  
Ryan S. Stowers

In the fields of regenerative medicine and tissue engineering, stem cells offer vast potential for treating or replacing diseased and damaged tissue. Much progress has been made in understanding stem cell biology, yielding protocols for directing stem cell differentiation toward the cell type of interest for a specific application. One particularly interesting and powerful signaling cue is the extracellular matrix (ECM) surrounding stem cells, a network of biopolymers that, along with cells, makes up what we define as a tissue. The composition, structure, biochemical features, and mechanical properties of the ECM are varied in different tissues and developmental stages, and serve to instruct stem cells toward a specific lineage. By understanding and recapitulating some of these ECM signaling cues through engineered ECM-mimicking hydrogels, stem cell fate can be directed in vitro. In this review, we will summarize recent advances in material systems to guide stem cell fate, highlighting innovative methods to capture ECM functionalities and how these material systems can be used to provide basic insight into stem cell biology or make progress toward therapeutic objectives.


2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Cristina D'Aniello ◽  
Federica Cermola ◽  
Eduardo Jorge Patriarca ◽  
Gabriella Minchiotti

Transcription factors and signaling molecules are well-known regulators of stem cell identity and behavior; however, increasing evidence indicates that environmental cues contribute to this complex network of stimuli, acting as crucial determinants of stem cell fate.L-Ascorbic acid (vitamin C (VitC)) has gained growing interest for its multiple functions and mechanisms of action, contributing to the homeostasis of normal tissues and organs as well as to tissue regeneration. Here, we review the main functions of VitC and its effects on stem cells, focusing on its activity as cofactor of Fe+2/αKG dioxygenases, which regulate the epigenetic signatures, the redox status, and the extracellular matrix (ECM) composition, depending on the enzymes’ subcellular localization. Acting as cofactor of collagen prolyl hydroxylases in the endoplasmic reticulum, VitC regulates ECM/collagen homeostasis and plays a key role in the differentiation of mesenchymal stem cells towards osteoblasts, chondrocytes, and tendons. In the nucleus, VitC enhances the activity of DNA and histone demethylases, improving somatic cell reprogramming and pushing embryonic stem cell towards the naive pluripotent state. The broad spectrum of actions of VitC highlights its relevance for stem cell biology in both physiology and disease.


2007 ◽  
Vol 27 (1-3) ◽  
pp. 165-171 ◽  
Author(s):  
Claudia Nesti ◽  
Livia Pasquali ◽  
Francesca Vaglini ◽  
Gabriele Siciliano ◽  
Luigi Murri

This mini-review summarizes the current literature on the role of mitochondrial DNA mutations and mitochondrial metabolism in stem cell biology. The possible uses of stem cells as a therapeutic tool in mitochondrial disorders are also reported.


Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1002
Author(s):  
Fabiola Marino ◽  
Mariangela Scalise ◽  
Eleonora Cianflone ◽  
Luca Salerno ◽  
Donato Cappetta ◽  
...  

Over the years strong evidence has been accumulated showing that aerobic physical exercise exerts beneficial effects on the prevention and reduction of cardiovascular risk. Exercise in healthy subjects fosters physiological remodeling of the adult heart. Concurrently, physical training can significantly slow-down or even reverse the maladaptive pathologic cardiac remodeling in cardiac diseases, improving heart function. The underlying cellular and molecular mechanisms of the beneficial effects of physical exercise on the heart are still a subject of intensive study. Aerobic activity increases cardiovascular nitric oxide (NO) released mainly through nitric oxidase synthase 3 activity, promoting endothelium-dependent vasodilation, reducing vascular resistance, and lowering blood pressure. On the reverse, an imbalance between increasing free radical production and decreased NO generation characterizes pathologic remodeling, which has been termed the “nitroso-redox imbalance”. Besides these classical evidence on the role of NO in cardiac physiology and pathology, accumulating data show that NO regulate different aspects of stem cell biology, including survival, proliferation, migration, differentiation, and secretion of pro-regenerative factors. Concurrently, it has been shown that physical exercise generates physiological remodeling while antagonizes pathologic remodeling also by fostering cardiac regeneration, including new cardiomyocyte formation. This review is therefore focused on the possible link between physical exercise, NO, and stem cell biology in the cardiac regenerative/reparative response to physiological or pathological load. Cellular and molecular mechanisms that generate an exercise-induced cardioprotective phenotype are discussed in regards with myocardial repair and regeneration. Aerobic training can benefit cells implicated in cardiovascular homeostasis and response to damage by NO-mediated pathways that protect stem cells in the hostile environment, enhance their activation and differentiation and, in turn, translate to more efficient myocardial tissue regeneration. Moreover, stem cell preconditioning by and/or local potentiation of NO signaling can be envisioned as promising approaches to improve the post-transplantation stem cell survival and the efficacy of cardiac stem cell therapy.


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