Activation of Pancreatic Stellate Cells Is Beneficial for Exocrine but Not Endocrine Cell Differentiation in the Developing Human Pancreas

Pancreatic stellate cells (PaSCs) are non-endocrine, mesenchymal-like cells that reside within the peri-pancreatic tissue of the rodent and human pancreas. PaSCs regulate extracellular matrix (ECM) turnover in maintaining the integrity of pancreatic tissue architecture. Although there is evidence indicating that PaSCs are involved in islet cell survival and function, its role in islet cell differentiation during human pancreatic development remains unclear. The present study examines the expression pattern and functional role of PaSCs in islet cell differentiation of the developing human pancreas from late 1st to 2nd trimester of pregnancy. The presence of PaSCs in human pancreata (8–22 weeks of fetal age) was characterized by ultrastructural, immunohistological, quantitative RT-PCR and western blotting approaches. Using human fetal PaSCs derived from pancreata at 14–16 weeks, freshly isolated human fetal islet-epithelial cell clusters (hIECCs) were co-cultured with active or inactive PaSCs in vitro. Ultrastructural and immunofluorescence analysis demonstrated a population of PaSCs near ducts and newly formed islets that appeared to make complex cell-cell dendritic-like contacts. A small subset of PaSCs co-localized with pancreatic progenitor-associated transcription factors (PDX1, SOX9, and NKX6-1). PaSCs were highly proliferative, with significantly higher mRNA and protein levels of PaSC markers (desmin, αSMA) during the 1st trimester of pregnancy compared to the 2nd trimester. Isolated human fetal PaSCs were identified by expression of stellate cell markers and ECM. Suppression of PaSC activation, using all-trans retinoic acid (ATRA), resulted in reduced PaSC proliferation and ECM proteins. Co-culture of hIECCs, directly on PaSCs or indirectly using Millicell® Inserts or using PaSC-conditioned medium, resulted in a reduction the number of insulin+ cells but a significant increase in the number of amylase+ cells. Suppression of PaSC activation or Notch activity during the co-culture resulted in an increase in beta-cell differentiation. This study determined that PaSCs, abundant during the 1st trimester of pancreatic development but decreased in the 2nd trimester, are located near ductal and islet structures. Direct and indirect co-cultures of hIECCs with PaSCs suggest that activation of PaSCs has opposing effects on beta-cell and exocrine cell differentiation during human fetal pancreas development, and that these effects may be dependent on Notch signaling.

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Stimulation of stellate cells by injured acinar cells: a model of acute pancreatitis induced by alcohol and fat (VLDL)

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.90468.2008 ◽

2009 ◽

Vol 297 (6) ◽

pp. G1163-G1171 ◽

Cited By ~ 25

Author(s):

Marco Siech ◽

Zhengfei Zhou ◽

Shaoxia Zhou ◽

Bernd Bair ◽

Andreas Alt ◽

...

Keyword(s):

Oxidative Stress ◽

Acute Pancreatitis ◽

Acinar Cell ◽

Cell Injury ◽

Stellate Cell ◽

Stellate Cells ◽

Pancreatic Acinar Cell ◽

Pancreatic Stellate Cells ◽

Matrix Synthesis ◽

Repair Mechanisms

Mechanisms leading to acute pancreatitis after a fat-enriched meal combined with excess alcohol are incompletely understood. We have studied the effects of alcohol and fat (VLDL) on pancreatic acinar cell (PAC) function, oxidative stress, and repair mechanisms by pancreatic stellate cells (PSC) leading to fibrogenesis. To do so, PAC (rat) were isolated and cultured up to 24 h. Ethanol and/or VLDL were added to PAC. We measured PAC function (amylase, lipase), injury (lactic dehydrogenase), apoptosis (TUNEL, Apo2.7, annexin V binding), oxidative stress, and lipid peroxidation (conjugated dienes, malondialdehyde, chemoluminescence); we also measured PSC proliferation (bromodeoxyuridine incorporation), matrix synthesis (immunofluorescence of collagens and fibronectin, fibronectin immunoassay), and fatty acids in PAC supernatants (gas chromatography). Within 6 h, cultured PAC degraded and hydrolyzed VLDL completely. VLDL alone (50 μg/ml) and in combination with alcohol (0.2, 0.5, and 1% vol/vol) induced PAC injury (LDL, amylase, and lipase release) within 2 h through generation of oxidative stress. Depending on the dose of VLDL and alcohol, apoptosis and/or necrosis were induced. Antioxidants (Trolox, Probucol) reduced the cytotoxic effect of alcohol and VLDL. Supernatants of alcohol/VLDL-treated PAC stimulated stellate cell proliferation and extracellular matrix synthesis. We concluded that, in the presence of lipoproteins, alcohol induces acinar cell injury. Our results provide a biochemical pathway for the clinical observation that a fat-enriched meal combined with excess alcohol consumption can induce acinar cell injury (acute pancreatitis) followed by repair mechanisms (proliferation and increased matrix synthesis in PSC).

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Pancreatic Stellate Cells: A Rising Translational Physiology Star as a Potential Stem Cell Type for Beta Cell Neogenesis

Frontiers in Physiology ◽

10.3389/fphys.2019.00218 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 2

Author(s):

Yunting Zhou ◽

Bo Sun ◽

Wei Li ◽

Junming Zhou ◽

Feng Gao ◽

...

Keyword(s):

Stem Cell ◽

Beta Cell ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Cell Type ◽

Stem Cell Type ◽

Beta Cell Neogenesis

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Hepatic and pancreatic stellate cells in focus

Biological Chemistry ◽

10.1515/bc.2009.121 ◽

2009 ◽

Vol 390 (10) ◽

Cited By ~ 42

Author(s):

Claus Kordes ◽

Iris Sawitza ◽

Dieter Häussinger

Keyword(s):

Cell Biology ◽

Stellate Cell ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Differentiation Potential ◽

Undifferentiated Cells ◽

Cell Niche ◽

Space Of Disse

Abstract Stellate cells are vitamin A-storing cells of liver and pancreas and have been described in all vertebrates ranging from lampreys (primitive fish) to humans, demonstrating their major importance. This cell type is thought to contribute to fibrosis, a condition characterized by an excess deposition of extracellular matrix proteins. Recently, the expression of stem/progenitor cell markers, such as CD133 (prominin-1) and Oct4, was discovered in hepatic stellate cells (HSCs) of rats. Moreover, HSCs possess signaling pathways important for maintenance of stemness and cell differentiation, such as hedgehog, β-catenin-dependent Wnt, and Notch signaling, and are resistant to CD95-mediated apoptosis. In analogy to a stem cell niche, some characteristics of quiescent HSC are maintained by aid of a special microenvironment located in the space of Dissé. Finally, stellate cells display a differentiation potential as investigated in vitro and in vivo. Collectively all these properties are congruently found in stem/progenitor cells and support the concept that stellate cells are undifferentiated cells, which might play an important role in liver regeneration. The present review highlights findings related to this novel aspect of stellate cell biology.

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GLP-1R agonist may activate pancreatic stellate cells to induce rat pancreatic tissue lesion

Pancreatology ◽

10.1016/j.pan.2013.07.281 ◽

2013 ◽

Vol 13 (5) ◽

pp. 498-501 ◽

Cited By ~ 7

Author(s):

Yongchao Yang ◽

Xiao Yu ◽

Lihua Huang ◽

Can Yu

Keyword(s):

Stellate Cells ◽

Pancreatic Tissue ◽

Pancreatic Stellate Cells ◽

Tissue Lesion

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Hypoxia activates pancreatic stellate cells: Development of an organotypic culture model of thick slices of normal human pancreas

Pancreatology ◽

10.1016/j.pan.2012.11.294 ◽

2012 ◽

Vol 12 (6) ◽

pp. 588

Author(s):

V. Rebours ◽

M. Albuquerque ◽

P. Ruszniewski ◽

A. Sauvanet ◽

V. Paradis ◽

...

Keyword(s):

Organotypic Culture ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Human Pancreas ◽

Culture Model ◽

Normal Human

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Nitric oxide signals are interlinked with calcium signals in normal pancreatic stellate cells upon oxidative stress and inflammation

Open Biology ◽

10.1098/rsob.160149 ◽

2016 ◽

Vol 6 (8) ◽

pp. 160149 ◽

Cited By ~ 21

Author(s):

Monika A. Jakubowska ◽

Pawel E. Ferdek ◽

Oleg V. Gerasimenko ◽

Julia V. Gerasimenko ◽

Ole H. Petersen

Keyword(s):

Nitric Oxide ◽

Stellate Cell ◽

Cell Communication ◽

Stellate Cells ◽

Cell System ◽

Pancreatic Stellate Cells ◽

Pancreatic Acinar Cells ◽

Signalling Pathways ◽

Striking Difference

The mammalian diffuse stellate cell system comprises retinoid-storing cells capable of remarkable transformations from a quiescent to an activated myofibroblast-like phenotype. Activated pancreatic stellate cells (PSCs) attract attention owing to the pivotal role they play in development of tissue fibrosis in chronic pancreatitis and pancreatic cancer. However, little is known about the actual role of PSCs in the normal pancreas. These enigmatic cells have recently been shown to respond to physiological stimuli in a manner that is markedly different from their neighbouring pancreatic acinar cells (PACs). Here, we demonstrate the capacity of PSCs to generate nitric oxide (NO), a free radical messenger mediating, for example, inflammation and vasodilatation. We show that production of cytosolic NO in PSCs is unambiguously related to cytosolic Ca 2+ signals. Only stimuli that evoke Ca 2+ signals in the PSCs elicit consequent NO generation. We provide fresh evidence for the striking difference between signalling pathways in PSCs and adjacent PACs, because PSCs, in contrast to PACs, generate substantial Ca 2+ -mediated and NOS-dependent NO signals. We also show that inhibition of NO generation protects both PSCs and PACs from necrosis. Our results highlight the interplay between Ca 2+ and NO signalling pathways in cell–cell communication, and also identify a potential therapeutic target for anti-inflammatory therapies.

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Galectin-1 induces chemokine production and proliferation in pancreatic stellate cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00511.2005 ◽

2006 ◽

Vol 290 (4) ◽

pp. G729-G736 ◽

Cited By ~ 48

Author(s):

Atsushi Masamune ◽

Masahiro Satoh ◽

Jun Hirabayashi ◽

Kenichi Kasai ◽

Kennichi Satoh ◽

...

Keyword(s):

Western Blot ◽

Blot Analysis ◽

Western Blot Analysis ◽

Stellate Cells ◽

Pancreatic Tissue ◽

Immunofluorescent Staining ◽

Pancreatic Stellate Cells ◽

Chemokine Production ◽

Cell Functions

Galectin-1 is a β-galactoside-binding lectin. Previous studies have shown that galectin-1 was expressed in fibroblasts of chronic pancreatitis and of desmoplastic reaction associated with pancreatic cancer. These fibroblasts are now recognized as activated pancreatic stellate cells (PSCs). Here, we examined the role of galectin-1 in cell functions of PSCs. PSCs were isolated from rat pancreatic tissue and used in their culture-activated phenotype unless otherwise stated. Expression of galectin-1 was assessed by Western blot analysis, RT-PCR, and immunofluorescent staining. The effects of recombinant galectin-1 on chemokine production and proliferation were evaluated. Activation of transcription factors was assessed by EMSA. Activation of MAPKs was examined by Western blot analysis using anti-phosphospecific antibodies. Galectin-1 was strongly expressed in culture-activated but not freshly isolated PSCs. Recombinant galectin-1 increased proliferation and production of monocyte chemoattractant protein-1 and cytokine-induced neutrophil chemoattractant-1. Galectin-1 activated ERK, JNK, activator protein-1, and NF-κB, but not p38 MAPK or Akt. Galectin-1 induced proliferation through ERK and chemokine production mainly through the activation of NF-κB and in part by JNK and ERK pathways. These effects of galectin-1 were abolished in the presence of thiodigalactosie, an inhibitor of β-galactoside binding. In conclusion, our results suggest a role of galectin-1 in chemokine production and proliferation through its β-galactoside binding activity in activated PSCs.

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Isolation of quiescent pancreatic stellate cells from rat and human pancreas

The Pancreapedia: Exocrine Pancreas Knowledge Base ◽

10.3998/panc.2011.10 ◽

2011 ◽

Cited By ~ 2

Keyword(s):

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Human Pancreas

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BMP2 inhibits TGF-β-induced pancreatic stellate cell activation and extracellular matrix formation

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00306.2012 ◽

2013 ◽

Vol 304 (9) ◽

pp. G804-G813 ◽

Cited By ~ 39

Author(s):

Xuxia Gao ◽

Yanna Cao ◽

Wenli Yang ◽

Chaojun Duan ◽

Judith F. Aronson ◽

...

Keyword(s):

Extracellular Matrix ◽

Cell Activation ◽

Transforming Growth Factor ◽

Stellate Cell ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Pancreatic Stellate Cells ◽

Steady Increase ◽

Pathological Feature

Activation of pancreatic stellate cells (PSCs) by transforming growth factor (TGF)-β is the key step in the development of pancreatic fibrosis, a common pathological feature of chronic pancreatitis (CP). Bone morphogenetic proteins (BMPs), members of the TGF-β superfamily, have anti-fibrogenic functions, in contrast to TGF-β, in the kidney, lung, and liver. However, it is not known whether BMPs have an anti-fibrogenic role in the pancreas. The current study was designed to investigate the potential anti-fibrogenic role of BMPs in the pancreas using an in vivo CP model and an in vitro PSC model. CP was induced by repetitive intraperitoneal injections of cerulein in adult Swiss Webster mice. The control mice received saline injections. Compared with the control, cerulein injections induced a time-dependent increase in acinar injury and progression of fibrosis and a steady increase in inflammation. Cerulein injections also induced increases of the extracellular matrix (ECM) protein fibronectin and of α-smooth muscle actin (α-SMA)-positive stellate cells (PSCs). The mice receiving cerulein injections showed increased BMP2 protein levels and phosphorylated Smad1 levels up to 4 wk and then declined at 8 wk to similar levels as the control. In vitro, the isolated mouse and human PSCs were cultured and pretreated with BMP2 followed by TGF-β treatment. BMP2 pretreatment inhibited TGF-β-induced α-SMA, fibronectin, and collagen type Ia expression. Knocking down Smad1 with small-interfering RNA reversed the inhibitory effect of BMP2 on TGF-β-induced α-SMA and fibronectin expression. Thus, BMP2 opposes the fibrogenic function of TGF-β in PSCs through the Smad1 signaling pathway.

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