scholarly journals Bmi1 lineage tracing identifies a self-renewing pancreatic acinar cell subpopulation capable of maintaining pancreatic organ homeostasis

2009 ◽  
Vol 106 (17) ◽  
pp. 7101-7106 ◽  
Author(s):  
Eugenio Sangiorgi ◽  
Mario R. Capecchi
Keyword(s):  
Stem Cells ◽  
Cell Biology ◽  
Exocrine Pancreas ◽  
Adult Stem Cells ◽  
Acinar Cells ◽  
Pancreatic Acinar Cell ◽  
Lineage Tracing ◽  
Pancreatic Acinar Cells ◽  
Cell Subpopulation ◽  
Self Renewal

A central question in stem cell biology is whether organ homeostasis is maintained in adult organs through undifferentiated stem cells or self-duplication of specialized cell populations. To address this issue in the exocrine pancreas we analyzed the Bmi1-labeled cell lineage of pancreatic acinar cells. Previously, we had shown that inducible linage tracing with Bmi1-Cre-estrogen receptor (ER) in the small intestine specifically, labels “classical” undifferentiated intestinal stem cells. In this article we demonstrate that the Bmi1-Cre-ER system labels a subpopulation of differentiated acinar cells in the exocrine pancreas whose derivatives are still present, at a steady-state level, 1 year after a single TM pulse. This study suggests that Bmi1 is a marker for a subpopulation of self-renewing acinar cells, indicating that self-renewal is not an exclusive feature of adult undifferentiated stem cells. Further, the extended period that Bmi1-labeled acinar cells retain a pulse of BrdU suggests that some of this subpopulation of cells are not continuously replicating, but rather are set aside until needed. This cellular behavior is again reminiscent of behavior normally associated with more classical adult stem cells. Setting aside cells capable of self-renewal until needed retains the advantage of protecting this subpopulation of cells from DNA damage induced during replication.

scholarly journals Advances and Applications in Stem Cell Biology

2012 ◽  
Vol 46 (2) ◽  
pp. 75-80
Author(s):  
Shamoli Bhattacharyya
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Biology ◽  
Adult Stem Cells ◽  
Great Promise ◽  
Stem Cell Biology ◽  
Self Renewal ◽  
Main Challenge ◽  
Basic Biology

ABSTRACT Mesenchymal stem cells have shown great promise as the source of adult stem cells for regenerative medicine. Present research efforts are directed at isolating these cells from various sources, growing them in vitro and maintaining their pluripotency as well as capacity for self renewal. It is crucial to identify the regulatory molecules which directly or indirectly control the proliferative status or influence the niche microenvironment. The main challenge is to understand the basic biology of the stem cells and manipulate them for further therapeutic applications. Considering their malignant potential, stem cells may be a double edged sword. While the benefits of these cells need to be harnessed judiciously, a significant amount of research is required before embarking on widespread use of this tool for the benefit of humanity. How to cite this article Bhattacharyya S. Advances and Applications in Stem Cell Biology. J Postgrad Med Edu Res 2012;46(2):75-80.

Effect of oxidative stress on cellular functions and cytosolic free calcium of rat pancreatic acinar cells

1997 ◽  
Vol 272 (6) ◽  
pp. G1489-G1498 ◽  
Author(s):  
H. Klonowski-Stumpe ◽  
R. Schreiber ◽  
M. Grolik ◽  
H. U. Schulz ◽  
D. Haussinger ◽  
...  
Keyword(s):  
Cell Injury ◽  
Cell Damage ◽  
Acinar Cells ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Free Calcium ◽  
Cellular Functions ◽  
Cytosolic Free Calcium ◽  
Catalyzed Oxidation ◽  
Sustained Increase

The present study evaluates the effect of free radicals generated by xanthine oxidase-catalyzed oxidation of hypoxanthine on cellular function of isolated rat pancreatic acinar cells. The results show that a rapid and sustained increase in intracellular Ca2+ concentration ([Ca2+]i) preceded all other morphological and functional alterations investigated. Radical-induced [Ca2+]i increase was largely inhibited by 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester, which prevents Ca2+ release from intracellular stores, but not by Ca2(+)-depleted medium. Radicals released Ca2+ from thapsigargin-insensitive, ryanodine-sensitive intracellular stores, whereas the secretagogue caerulein at physiological concentrations mainly released Ca2+ from thapsigargin-sensitive stores. In contrast to effects of the secretagogue, radical-induced Ca2+ changes did not cause luminal protein secretion but cell death. In single-cell measurements, both secretagogue and radicals induced oscillations of [Ca2+]i. Radical-induced oscillations had a lower frequency but similar amplitude when compared with caerulein-induced oscillations. 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid and ryanodine, which prevented the radical-induced Ca2+ increase without altering the generation of radicals, markedly reduced the radical-induced cell damage. These results suggest that the Ca2+ increase mediates the radical-induced cell injury. The studies also indicate that not only the extent and duration but also the origin of [Ca2+]i release as well as the frequency of Ca2+ oscillations may determine whether a pancreatic acinar cell will secrete or die.

scholarly journals The Act of Controlling Adult Stem Cell Dynamics: Insights from Animal Models

Biomolecules ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 667
Author(s):  
Meera Krishnan ◽  
Sahil Kumar ◽  
Luis Johnson Kangale ◽  
Eric Ghigo ◽  
Prasad Abnave
Keyword(s):  
Stem Cells ◽  
Animal Models ◽  
Adult Stem Cells ◽  
The Body ◽  
In Vivo Studies ◽  
Self Renewal ◽  
Hematopoietic Stem ◽  
Organ Systems

Adult stem cells (ASCs) are the undifferentiated cells that possess self-renewal and differentiation abilities. They are present in all major organ systems of the body and are uniquely reserved there during development for tissue maintenance during homeostasis, injury, and infection. They do so by promptly modulating the dynamics of proliferation, differentiation, survival, and migration. Any imbalance in these processes may result in regeneration failure or developing cancer. Hence, the dynamics of these various behaviors of ASCs need to always be precisely controlled. Several genetic and epigenetic factors have been demonstrated to be involved in tightly regulating the proliferation, differentiation, and self-renewal of ASCs. Understanding these mechanisms is of great importance, given the role of stem cells in regenerative medicine. Investigations on various animal models have played a significant part in enriching our knowledge and giving In Vivo in-sight into such ASCs regulatory mechanisms. In this review, we have discussed the recent In Vivo studies demonstrating the role of various genetic factors in regulating dynamics of different ASCs viz. intestinal stem cells (ISCs), neural stem cells (NSCs), hematopoietic stem cells (HSCs), and epidermal stem cells (Ep-SCs).

scholarly journals YAP regulates porcine skin-derived stem cells self-renewal partly by repressing Wnt/β-catenin signaling pathway

2021 ◽  
Author(s):  
Hong-Chen Yan ◽  
Yu Sun ◽  
Ming-Yu Zhang ◽  
Shu-Er Zhang ◽  
Jia-Dong Sun ◽  
...  
Keyword(s):  
Stem Cells ◽  
Signaling Pathway ◽  
Adult Stem Cells ◽  
Self Renewal ◽  
Human Ascs ◽  
Regulation Mechanisms ◽  
Interfering Rna ◽  
Pluripotency Genes

Abstract Background Skin-derived stem cells (SDSCs) are a class of adult stem cells (ASCs) that have the ability to self-renew and differentiate. The regulation mechanisms involved in the differentiation of ASCs is a hot topic. Porcine models have close similarities to humans and porcine SDSCs (pSDSCs) offer an ideal in vitro model to investigate human ASCs. To date, studies concerning the role of yes-associated protein (YAP) in ASCs are limited, and the mechanism of its influence on self-renewal and differentiation of ASCs remain unclear. In this paper, we explore the link between the transcriptional regulator YAP and the fate of pSDSCs. Results We found that YAP promotes the pluripotent state of pSDSCs by maintaining the high expression of the pluripotency genes Sox2, Oct4. The overexpression of YAP prevented the differentiation of pSDSCs and the depletion of YAP by small interfering RNA (siRNAs) suppressed the self-renewal of pSDSCs. In addition, we found that YAP regulates the fate of pSDSCs through a mechanism related to the Wnt/β-catenin signaling pathway. When an activator of the Wnt/β-catenin signaling pathway, CHIR99021, was added to pSDSCs overexpressing YAP the ability of pSDSCs to differentiate was partially restored. Conversely, when XAV939 an inhibitor of Wnt/β-catenin signaling pathway, was added to YAP knockdown pSDSCs a higher self-renewal ability resulted. Conclusions our results suggested that, YAP and the Wnt/β-catenin signaling pathway interact to regulate the fate of pSDSCs.

scholarly journals Organotypic Culture of Acinar Cells for the Study of Pancreatic Cancer Initiation

Cancers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2606
Author(s):  
Carlotta Paoli ◽  
Alessandro Carrer
Keyword(s):  
Pancreatic Cancer ◽  
Ex Vivo ◽  
Acinar Cells ◽  
Lineage Tracing ◽  
Metabolic Reprogramming ◽  
Pancreatic Acinar Cells ◽  
Ductal Adenocarcinoma ◽  
Molecular Features ◽  
The Impact

The carcinogenesis of pancreatic ductal adenocarcinoma (PDA) progresses according to multi-step evolution, whereby the disease acquires increasingly aggressive pathological features. On the other hand, disease inception is poorly investigated. Decoding the cascade of events that leads to oncogenic transformation is crucial to design strategies for early diagnosis as well as to tackle tumor onset. Lineage-tracing experiments demonstrated that pancreatic cancerous lesions originate from acinar cells, a highly specialized cell type in the pancreatic epithelium. Primary acinar cells can survive in vitro as organoid-like 3D spheroids, which can transdifferentiate into cells with a clear ductal morphology in response to different cell- and non-cell-autonomous stimuli. This event, termed acinar-to-ductal metaplasia, recapitulates the histological and molecular features of disease initiation. Here, we will discuss the isolation and culture of primary pancreatic acinar cells, providing a historical and technical perspective. The impact of pancreatic cancer research will also be debated. In particular, we will dissect the roles of transcriptional, epigenetic, and metabolic reprogramming for tumor initiation and we will show how that can be modeled using ex vivo acinar cell cultures. Finally, mechanisms of PDA initiation described using organotypical cultures will be reviewed.

scholarly journals Mechanism and regulation of folate uptake by pancreatic acinar cells: effect of chronic alcohol consumption

2010 ◽  
Vol 298 (6) ◽  
pp. G985-G993 ◽  
Author(s):  
Hamid M. Said ◽  
Lisa Mee ◽  
V. Thillai Sekar ◽  
Balasubramaniem Ashokkumar ◽  
Stephen J. Pandol
Keyword(s):  
Acinar Cells ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Exocrine Function ◽  
Acid Uptake ◽  
Human Pancreas ◽  
Chronic Alcohol ◽  
Transport Inhibitors ◽  
Pancreatic Exocrine ◽  
One Carbon Metabolism

Folate plays an essential role in one-carbon metabolism, and a relationship exists between methyl group metabolism and pancreatic exocrine function. Little, however, is known about the mechanism(s) and regulation of folate uptake by pancreatic acinar cells and the effect of chronic alcohol use on the process. We addressed these issues using the rat-derived pancreatic acinar cell line AR42J and freshly isolated primary rat pancreatic acinar cells as models. We found [3H]folic acid uptake to be 1) temperature and pH dependent with a higher uptake at acidic than at neutral/alkaline pH; 2) saturable as a function of substrate concentration at both buffer pH 7.4 and 6.0; 3) inhibited by folate structural analogs and by anion transport inhibitors at both buffer pH 7.4 and 6.0; 4) trans-stimulated by unlabeled folate; 5) adaptively regulated by the prevailing extracellular folate level, and 6) inhibited by modulators of the cAMP/PKA-mediated pathway. Both the reduced folate carrier (RFC) and the proton-coupled folate transporter (PCFT) were found to be expressed in AR42J and in primary pancreatic acinar cells, as well as in native human pancreas with expression of RFC being higher than PCFT. Chronic alcohol feeding of rats (4 wk; 36% of calories from ethanol) led to a significant decrease in folate uptake by freshly isolated primary pancreatic acinar cells compared with cells from pair-fed controls; this effect was associated with a parallel decrease in the level of expression of RFC and PCFT. These studies reveal that folate uptake by pancreatic acinar cells is via a regulated carrier-mediated process which may involve RFC and PCFT. In addition, chronic alcohol feeding leads to a marked inhibition in folate uptake by pancreatic acinar cells, an effect that is associated with reduction in level of expression of RFC and PCFT.

MiR-155 aggravates impaired autophagy of pancreatic acinar cells through targeting Rictor

2020 ◽  
Vol 52 (2) ◽  
pp. 192-199 ◽  
Author(s):  
Xueming Zhang ◽  
Jiangtao Chu ◽  
Haijun Sun ◽  
Dali Zhao ◽  
Biao Ma ◽  
...  
Keyword(s):  
Acinar Cells ◽  
Immunofluorescence Assay ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Luciferase Reporter ◽  
Cellular Model ◽  
Protein Levels ◽  
Ar42j Cells ◽  
Direct Target ◽  
Dual Luciferase Reporter Assay

Abstract The aim of this study was to investigate the role and mechanism of miR-155 in regulating autophagy in a caerulein-induced acute pancreatitis (AP) cellular model. GFP-LC3 immunofluorescence assay was performed to detect autophagy vesicle formation in pancreatic acinar cell line AR42J. AR42J cells were transfected with miR-155 mimic, inhibitor, and corresponding controls to explore the effect of miR-155 on autophagy. The protein levels of LC3-I, LC3-II, Beclin-1, and p62 were analyzed by western blot analysis. Dual-luciferase reporter assay was performed to verify the interaction between miR-155 and Rictor (RPTOR independent companion of MTOR complex 2). The results showed that caerulein treatment induced impaired autophagy as evidenced by an increase in the accumulation of p62 together with LC3-II in AR42J cells, accompanied by miR-155 upregulation. Furthermore, miR-155 overexpression aggravated, whereas miR-155 silencing reduced the caerulein-induced impairment of autophagy. Mechanistically, Rictor was confirmed to be a direct target of miR-155, which could rescue the miR-155 overexpression-mediated aggravation of impaired autophagy. Collectively, these findings indicate that miR-155 aggravates impaired autophagy in caerulein-treated pancreatic acinar cells by targeting Rictor.

Crambene induces pancreatic acinar cell apoptosis via the activation of mitochondrial pathway

2006 ◽  
Vol 291 (1) ◽  
pp. G95-G101 ◽  
Author(s):  
Yang Cao ◽  
Sharmila Adhikari ◽  
Abel Damien Ang ◽  
Marie Véronique Clément ◽  
Matthew Wallig ◽  
...  
Keyword(s):  
Acinar Cell ◽  
Cell Apoptosis ◽  
Caspase 3 ◽  
Fas Ligand ◽  
Annexin V ◽  
Acinar Cells ◽  
Mitochondrial Pathway ◽  
Pancreatic Acinar Cell ◽  
Pancreatic Acinar Cells ◽  
Pancreatic Acini

We investigated the apoptotic pathway activated by crambene (1-cyano-2-hydroxy-3-butene), a plant nitrile, on pancreatic acinar cells. As evidenced by annexin V-FITC staining, crambene treatment for 3 h induced the apoptosis but not necrosis of pancreatic acini. Caspase-3, -8, and -9 activities in acini treated with crambene were significantly higher than in untreated acini. Treatment with caspase-3, -8, and -9 inhibitors inhibited annexin V staining, as well as caspase-3 activity, pointing to an important role of these caspases in crambene-induced acinar cell apoptosis. The mitochondrial membrane potential was collapsed, and cytochrome c was released from the mitochondria in crambene-treated acini. Neither TNF-α nor Fas ligand levels were changed in pancreatic acinar cells after crambene treatment. These results provide evidence for the induction of pancreatic acinar cell apoptosis in vitro by crambene and suggest the involvement of mitochondrial pathway in pancreatic acinar cell apoptosis.

scholarly journals Cytokine receptor-Eb1 interaction couples cell polarity and fate during asymmetric cell division

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Cuie Chen ◽  
Ryan Cummings ◽  
Aghapi Mordovanakis ◽  
Alan J Hunt ◽  
Michael Mayer ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cell Division ◽  
Cell Fate ◽  
Cell Polarity ◽  
Adult Stem Cells ◽  
Asymmetric Cell Division ◽  
Cytokine Receptor ◽  
Spindle Orientation ◽  
Germline Stem Cells ◽  
Self Renewal

Asymmetric stem cell division is a critical mechanism for balancing self-renewal and differentiation. Adult stem cells often orient their mitotic spindle to place one daughter inside the niche and the other outside of it to achieve asymmetric division. It remains unknown whether and how the niche may direct division orientation. Here we discover a novel and evolutionary conserved mechanism that couples cell polarity to cell fate. We show that the cytokine receptor homolog Dome, acting downstream of the niche-derived ligand Upd, directly binds to the microtubule-binding protein Eb1 to regulate spindle orientation in Drosophila male germline stem cells (GSCs). Dome’s role in spindle orientation is entirely separable from its known function in self-renewal mediated by the JAK-STAT pathway. We propose that integration of two functions (cell polarity and fate) in a single receptor is a key mechanism to ensure an asymmetric outcome following cell division.

scholarly journals Troy+ brain stem cells cycle through quiescence and regulate their number by sensing niche occupancy

2018 ◽  
Vol 115 (4) ◽  
pp. E610-E619 ◽  
Author(s):  
Onur Basak ◽  
Teresa G. Krieger ◽  
Mauro J. Muraro ◽  
Kay Wiebrands ◽  
Daniel E. Stange ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Cell Number ◽  
Lineage Tracing ◽  
Rapid Expansion ◽  
Molecular Signature ◽  
Genetic Lineage ◽  
Proliferating Cells ◽  
Self Renewal ◽  
Genetic Lineage Tracing

The adult mouse subependymal zone provides a niche for mammalian neural stem cells (NSCs). However, the molecular signature, self-renewal potential, and fate behavior of NSCs remain poorly defined. Here we propose a model in which the fate of active NSCs is coupled to the total number of neighboring NSCs in a shared niche. Using knock-in reporter alleles and single-cell RNA sequencing, we show that the Wnt target Tnfrsf19/Troy identifies both active and quiescent NSCs. Quantitative analysis of genetic lineage tracing of individual NSCs under homeostasis or in response to injury reveals rapid expansion of stem-cell number before some return to quiescence. This behavior is best explained by stochastic fate decisions, where stem-cell number within a shared niche fluctuates over time. Fate mapping proliferating cells using a Ki67iresCreER allele confirms that active NSCs reversibly return to quiescence, achieving long-term self-renewal. Our findings suggest a niche-based mechanism for the regulation of NSC fate and number.

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