scholarly journals Molecular and Morphological Signatures of Chordate Development: Two Distinct Pathways, One Tunicate

2019 ◽  
Author(s):  
Mark Kowarsky ◽  
Chiara Anselmi ◽  
Kohji Hotta ◽  
Paolo Burighel ◽  
Giovanna Zaniolo ◽  
...  

SummaryAll chordates, including urochordates such as tunicates, develop through embryogenesis. The chordate larvae of colonial tunicates metamorphose to lose all chordate structures such as notochord, neural tube, segmented musculature, and then develop by asexual reproduction [blastogenesis], whereby stem cells form tissues and organs. These two developmental pathways establish the same body axis, morphogenetic patterning and organ formation. It is unknown if this convergent morphology implies convergent cellular and molecular mechanisms, and whether the stem cells that mediate these processes differ. Using the colonial tunicate Botryllus schlosseri, we combined transcriptome sequencing and multiple microscopy techniques to study the molecular and morphological signatures of cells at each developmental stage of embryogenesis and blastogenesis. This revealed that the molecular programs are distinct, but the blastogenic tissue-specific stem cells and embryonic precursor populations share similar molecular profiles. By comparing embryogenesis in other chordates we found shared developmental principles, highlighting transcription factors as key evolutionary conserved elements. This study establishes a platform for advancing the science of stem cell biology and regulation of development and regeneration.

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.


Cells ◽  
2018 ◽  
Vol 7 (12) ◽  
pp. 255 ◽  
Author(s):  
Miruna Mihaela Micheu ◽  
Alina Ioana Scarlatescu ◽  
Alexandru Scafa-Udriste ◽  
Maria Dorobantu

Despite significant progress in treating ischemic cardiac disease and succeeding heart failure, there is still an unmet need to develop effective therapeutic strategies given the persistent high-mortality rate. Advances in stem cell biology hold great promise for regenerative medicine, particularly for cardiac regeneration. Various cell types have been used both in preclinical and clinical studies to repair the injured heart, either directly or indirectly. Transplanted cells may act in an autocrine and/or paracrine manner to improve the myocyte survival and migration of remote and/or resident stem cells to the site of injury. Still, the molecular mechanisms regulating cardiac protection and repair are poorly understood. Stem cell fate is directed by multifaceted interactions between genetic, epigenetic, transcriptional, and post-transcriptional mechanisms. Decoding stem cells’ “panomic” data would provide a comprehensive picture of the underlying mechanisms, resulting in patient-tailored therapy. This review offers a critical analysis of omics data in relation to stem cell survival and differentiation. Additionally, the emerging role of stem cell-derived exosomes as “cell-free” therapy is debated. Last but not least, we discuss the challenges to retrieve and analyze the huge amount of publicly available omics data.


2015 ◽  
Author(s):  
◽  
Jason Neville Sterrenberg

The therapeutic potential of stem cells is already being harnessed in clinical trails. Of even greater therapeutic potential has been the discovery of mechanisms to reprogram differentiated cells into a pluripotent stem cell-like state known as induced pluripotent stem cells (iPSCs). Stem cell nature is governed and maintained by a hierarchy of transcription factors, the apex of which is OCT4. Although much research has elucidated the transcriptional regulation of OCT4, OCT4 regulated gene expression profiles and OCT4 transcriptional activation mechanisms in both stem cell biology and cellular reprogramming to iPSCs, the fundamental biochemistry surrounding the OCT4 transcription factor remains largely unknown. In order to analyze the biochemical relationship between HSP90 and human OCT4 we developed an exogenous active human OCT4 expression model with human OCT4 under transcriptional control of a constitutive promoter. We identified the direct interaction between HSP90 and human OCT4 despite the fact that the proteins predominantly display differential subcellular localizations. We show that HSP90 inhibition resulted in degradation of human OCT4 via the ubiquitin proteasome degradation pathway. As human OCT4 and HSP90 did not interact in the nucleus, we suggest that HSP90 functions in the cytoplasmic stabilization of human OCT4. Our analysis suggests HSP90 inhibition inhibits the transcriptional activity of human OCT4 dimers without affecting monomeric OCT4 activity. Additionally our data suggests that the HSP90 and human OCT4 complex is modulated by phosphorylation events either promoting or abrogating the interaction between HSP90 and human OCT4. Our data suggest that human OCT4 displays the characteristics describing HSP90 client proteins, therefore we identify human OCT4 as a putative HSP90 client protein. The regulation of the transcription factor OCT4 by HSP90 provides fundamental insights into the complex biochemistry of stem cell biology. This may also be suggestive that HSP90 not only regulates stem cell biology by maintaining routine cellular homeostasis but additionally through the direct regulation of pluripotency factors.


2021 ◽  
pp. 39-51
Author(s):  
Jonathan Slack

‘Personalized pluripotent stem cells’ discusses cloning and its connection to stem cell biology. Somatic cell nuclear transplantation into oocytes can make personalized pluripotent stem cells as a perfect genetic match to a specific patient that provoke no immune rejection on grafting. Because this procedure involves generation of cells but no formation of an actual cloned individual, it has become known as human therapeutic cloning. Induced pluripotent stem cells (iPS cells) are made by introducing a few specific genes into normal cells. They are also a perfect genetic match to the individual donating the normal cells and because they are easy to make are now the preferred source.


2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Fernando de Sá Silva ◽  
Paula Nascimento Almeida ◽  
João Vitor Paes Rettore ◽  
Claudinéia Pereira Maranduba ◽  
Camila Maurmann de Souza ◽  
...  

Stem cells, both embryonic and adult, due to the potential for application in tissue regeneration have been the target of interest to the world scientific community. In fact, stem cells can be considered revolutionary in the field of medicine, especially in the treatment of a wide range of human diseases. However, caution is needed in the clinical application of such cells and this is an issue that demands more studies. This paper will discuss some controversial issues of importance for achieving cell therapy safety and success. Particularly, the following aspects of stem cell biology will be presented: methods for stem cells culture, teratogenic or tumorigenic potential, cellular dose, proliferation, senescence, karyotyping, and immunosuppressive activity.


2015 ◽  
Vol 156 (42) ◽  
pp. 1683-1694
Author(s):  
Gyöngyi Kudlik ◽  
Zsolt Matula ◽  
Tamás Kovács ◽  
S. Veronika Urbán ◽  
Ferenc Uher

The neural crest is a transient, multipotent, migratory cell population that is unique to vertebrate embryos and gives rise to many derivatives, ranging from the neuronal and glial components of the peripheral nervous system to the ectomesenchymal derivatives of the craniofacial area and pigment cells in the skin. Intriguingly, the neural crest derived stem cells are not only present in the embryonic neural crest, but also in their target tissues in the fetus and adult. These postmigratory stem cells, at least partially, resemble their multipotency. Moreover, fully differentiated neural crest-derived cells such as Schwann cells and melanocytes are able to dedifferentiate into stem-like progenitors. Here the authors review current understanding of this unique plasticity and its potential application in stem cell biology as well as in regenerative medicine. Orv. Hetil., 2015, 156(42), 1683–1694.


Hematology ◽  
2003 ◽  
Vol 2003 (1) ◽  
pp. 398-418 ◽  
Author(s):  
George Q. Daley ◽  
Margaret A. Goodell ◽  
Evan Y. Snyder

Abstract Studies of the regenerating hematopoietic system have led to the definition of many of the fundamental principles of stem cell biology. Therapies based on a range of tissue stem cells have been widely touted as a new treatment modality, presaging an emerging new specialty called regenerative medicine that promises to harness stem cells from embryonic and somatic sources to provide replacement cell therapies for genetic, malignant, and degenerative conditions. Insights borne from stem cell biology also portend development of protein and small molecule therapeutics that act on endogenous stem cells to promote repair and regeneration. Much of the newfound enthusiasm for regenerative medicine stems from the hope that advances in the laboratory will be followed soon thereafter by breakthrough treatments in the clinic. But how does one sort through the hype to judge the true promise? Are stem cell biologists and the media building expectations that cannot be met? Which diseases can be treated, and when can we expect success? In this review, we outline the realms of investigation that are capturing the most attention, and consider the current state of scientific understanding and controversy regarding the properties of embryonic and somatic (adult) stem cells. Our objective is to provide a framework for appreciating the promise while at the same time understanding the challenges behind translating fundamental stem cell biology into novel clinical therapies.


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 ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1380-1380
Author(s):  
Marc H.G.P. Raaijmakers ◽  
Elke P.L.M. de Grouw ◽  
Louis T.F. van de Locht ◽  
Bert A. van der Reijden ◽  
Theo J.M. de Witte ◽  
...  

Abstract In most cases of acute myeloid leukemia (AML) CD34+CD38− cells are considered to be stem cells, responsible for the maintenance and relapse of AML. ATP binding cassette transporters function in the extrusion of xenobiotics and chemotherapeutical compounds, and may be involved in therapy resistance. Elucidation of mechanisms conferring drug resistance to CD34+CD38− cells is essential to provide novel targets for stem cell eradication in AML. We studied gene expression of all 45 transmembrane ABC transporters (the complete ABCA, B, C, D and G family) in human hematopoietic CD34+CD38− cells and more committed CD34+CD38+ progenitor cells, from healthy donors and patients with non-hematological diseases (N=11) and AML patients (N=11). Gene expression was assessed using a novel real-time RT-PCR approach with micro fluidic cards. In normal CD34+CD38− cells 36 ABC transporters were expressed, 22 of these displayed significant higher expression in the CD34+CD38− cell fraction compared to the CD34+CD38+ cell fraction. In addition to the known stem cell transporters (ABCB1, ABCC1 and ABCG2) these differential expressed genes included many members not previously associated with stem cell biology. In AML the ABC transporter expression profile was largely conserved, including expression of all 13 known drug transporters. These data suggest an important role for many ABC transporters in hematopoietic stem cell biology. In addition, the preferential expression of a high number of drug transport related transporters predicts that broad spectrum inhibition of ABC transporters is likely to be required for CD34+38− stem cell eradication in AML. This approach will, apart from affecting the leukemic stem cells, equally affect the normal stem cells.


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