Enhanced Characterization of Beta Cell Mass in a Tg(Pdx1-GFP) Mouse Model of Beta Cell Destruction

Abstract IntroductionMeasurement of pancreatic beta cell mass in animal models is a common assay in diabetes researches. Novel whole-organ clearance methods in conjunction with transgenic mouse models hold tremendous promise to improve methods for beta cell mass measurement. Here, we propose a refined method to estimate the beta cell mass using a new transgenic Tg(Pdx1-GFP) mouse model and a recently developed free-of-acrylamide clearing tissue (FACT) protocol. MethodsFirst, we generated and evaluated a Tg(Pdx1-GFP) transgenic mouse model. By using the FACT protocol in this model, we could quantify the beta cell mass and alloxan-induced beta cell destruction in whole pancreas specimens.ResultsTg(Pdx1-GFP) transgenic mice expressed green fluorescent protein (GFP) only in the beta cells of the pancreas and limited to the beta cells. This GFP expression enabled us to accurately measure beta cell loss in a beta cell destruction model. The results suggest that our proposed method can be used as a simple, rapid assay for beta cell mass measurement in studies of islet biology and diabetes.ConclusionThe Tg(Pdx1-GFP) transgenic mouse in conjunction with the FACT protocol can enhance large-scale screening studies in the field of diabetes.

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2144-P: Early Administration of Dapagliflozin Preserves Pancreatic Beta-Cell Mass through an Epigenetic Modification in a Mouse Model of Type 2 Diabetes

Diabetes ◽

10.2337/db19-2144-p ◽

2019 ◽

Vol 68 (Supplement 1) ◽

pp. 2144-P

Author(s):

SHUN-ICHIRO ASAHARA ◽

AYUMI KANNO ◽

YOSHIAKI KIDO

Keyword(s):

Type 2 Diabetes ◽

Mouse Model ◽

Beta Cell ◽

Epigenetic Modification ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

Early Administration ◽

Pancreatic Beta Cell Mass

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Update on the Protective Molecular Pathways Improving Pancreatic Beta-Cell Dysfunction

Mediators of Inflammation ◽

10.1155/2013/750540 ◽

2013 ◽

Vol 2013 ◽

pp. 1-14 ◽

Cited By ~ 14

Author(s):

Alessandra Puddu ◽

Roberta Sanguineti ◽

François Mach ◽

Franco Dallegri ◽

Giorgio Luciano Viviani ◽

...

Keyword(s):

Beta Cell ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Cell Function ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

Beta Cell Dysfunction ◽

Molecular Pathways ◽

Cell Dysfunction

The primary function of pancreatic beta-cells is to produce and release insulin in response to increment in extracellular glucose concentrations, thus maintaining glucose homeostasis. Deficient beta-cell function can have profound metabolic consequences, leading to the development of hyperglycemia and, ultimately, diabetes mellitus. Therefore, strategies targeting the maintenance of the normal function and protecting pancreatic beta-cells from injury or death might be crucial in the treatment of diabetes. This narrative review will update evidence from the recently identified molecular regulators preserving beta-cell mass and function recovery in order to suggest potential therapeutic targets against diabetes. This review will also highlight the relevance for novel molecular pathways potentially improving beta-cell dysfunction.

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Phenylpropenoic acid glucoside augments pancreatic beta cell mass in high-fat diet-fed mice and protects beta cells from ER stress-induced apoptosis

Molecular Nutrition & Food Research ◽

10.1002/mnfr.201400211 ◽

2014 ◽

Vol 58 (10) ◽

pp. 1980-1990 ◽

Cited By ~ 20

Author(s):

Iris Mathijs ◽

Daniel A. Da Cunha ◽

Eddy Himpe ◽

Laurence Ladriere ◽

Nireshni Chellan ◽

...

Keyword(s):

Beta Cell ◽

Er Stress ◽

Beta Cells ◽

High Fat Diet ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

High Fat ◽

Induced Apoptosis ◽

Pancreatic Beta Cell Mass

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Defective exocytosis and processing of insulin in a cystic fibrosis mouse model

Journal of Endocrinology ◽

10.1530/joe-18-0570 ◽

2019 ◽

Vol 241 (1) ◽

pp. 45-57 ◽

Cited By ~ 2

Author(s):

A Edlund ◽

M Barghouth ◽

M Hühn ◽

M Abels ◽

J S E Esguerra ◽

...

Keyword(s):

Cystic Fibrosis ◽

Mouse Model ◽

Beta Cell ◽

Cell Function ◽

Pancreatic Beta Cell ◽

Hormone Secretion ◽

Cell Mass ◽

Beta Cell Mass ◽

Cell Number

Cystic fibrosis-related diabetes (CFRD) is a common complication for patients with cystic fibrosis (CF), a disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR). The cause of CFRD is unclear, but a commonly observed reduction in first-phase insulin secretion suggests defects at the beta cell level. Here we aimed to examine alpha and beta cell function in the Cftr tm1 EUR/F508del mouse model (C57BL/6J), which carries the most common human mutation in CFTR, the F508del mutation. CFTR expression, beta cell mass, insulin granule distribution, hormone secretion and single cell capacitance changes were evaluated using islets (or beta cells) from F508del mice and age-matched wild type (WT) mice aged 7–10 weeks. Granular pH was measured with DND-189 fluorescence. Serum glucose, insulin and glucagon levels were measured in vivo, and glucose tolerance was assessed using IPGTT. We show increased secretion of proinsulin and concomitant reduced secretion of C-peptide in islets from F508del mice compared to WT mice. Exocytosis and number of docked granules was reduced. We confirmed reduced granular pH by CFTR stimulation. We detected decreased pancreatic beta cell area, but unchanged beta cell number. Moreover, the F508del mutation caused failure to suppress glucagon secretion leading to hyperglucagonemia. In conclusion, F508del mice have beta cell defects resulting in (1) reduced number of docked insulin granules and reduced exocytosis and (2) potential defective proinsulin cleavage and secretion of immature insulin. These observations provide insight into the functional role of CFTR in pancreatic islets and contribute to increased understanding of the pathogenesis of CFRD.

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The Class I Histone Deacetylase Inhibitor MS-275 Prevents Pancreatic Beta Cell Death Induced by Palmitate

Journal of Diabetes Research ◽

10.1155/2014/195739 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Valérie Plaisance ◽

Laure Rolland ◽

Valéry Gmyr ◽

Jean-Sébastien Annicotte ◽

Julie Kerr-Conte ◽

...

Keyword(s):

Cell Death ◽

Beta Cell ◽

Er Stress ◽

Beta Cells ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

Activating Transcription Factor 3 ◽

Beta Cell Death ◽

Stress Markers

Elevation of the dietary saturated fatty acid palmitate contributes to the reduction of functional beta cell mass in the pathogenesis of type 2 diabetes. The diabetogenic effect of palmitate is achieved by increasing beta cell death through induction of the endoplasmic reticulum (ER) stress markers including activating transcription factor 3 (Atf3) and CAAT/enhancer-binding protein homologous protein-10 (Chop). In this study, we investigated whether treatment of beta cells with the MS-275, a HDAC1 and HDAC3 activity inhibitor which prevents beta cell death elicited by cytokines, is beneficial for combating beta cell dysfunction caused by palmitate. We show that culture of isolated human islets and MIN6 cells with MS-275 reduced apoptosis evoked by palmitate. The protective effect of MS-275 was associated with the attenuation of the expression of Atf3 and Chop. Silencing of HDAC3, but not of HDAC1, mimicked the effects of MS-275 on the expression of the two ER stress markers and apoptosis. These data point to HDAC3 as a potential drug target for preserving beta cells against lipotoxicity in diabetes.

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TRAIL induces proliferation in rodent pancreatic beta cells via AKT activation

Journal of Molecular Endocrinology ◽

10.1530/jme-20-0037 ◽

2021 ◽

Author(s):

Sevim Kahraman ◽

Ozlem Yilmaz ◽

Hasan Ali Altunbas ◽

Ercument Dirice ◽

Ahter Dilsad Sanlioglu

Keyword(s):

Beta Cell ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

Min6 Cells ◽

Akt Activation ◽

Proliferative Effect ◽

Beta Cell Line

Strategies to increase functional pancreatic beta cell mass is of great interest in diabetes-related research. TNF-related apoptosis-inducing ligand (TRAIL) is well-known to promote proliferation and survival in various cell types, including vascular smooth muscle and endothelial cells. Correlation between the protective nature of TRAIL on these cells and its proliferative effect is noteworthy. TRAIL’s seemingly protective/therapeutic effect in diabetes prompted us to question whether it may act as an inducer of proliferation in pancreatic beta cells. We used rat primary islet cells and MIN6 mouse beta cell line to investigate TRAIL-induced proliferation. Cell viability and/or death was analysed by MTT, WST-1, and annexin-V/PI assays, while proliferation rates and pathways were assessed via immunocytochemical and Western blot analyses. Receptor neutralization antibodies identified the mediator receptors. Recombinant soluble TRAIL (sTRAIL) treatment led to 1.6-fold increased proliferation in insulin-positive cells in dispersed rat islets compared to the untreated group, while adenovirus-mediated overexpression of TRAIL increased the number of proliferating beta cells up to more than 6-fold. sTRAIL or adenoviral vector-mediated TRAIL overexpression induced proliferation in MIN6 cells also. TRAIL’s proliferative effect was mediated via AKT activation, which was suppressed upon specific inhibition. Neutralization of each TRAIL receptor reversed the proliferative effect to some degree, with the highest level of inhibition in death receptor 5 (DR5) blockage in MIN6 cells, and in decoy receptor 1 (DcR1) blockage in primary rat beta cells. Thus, TRAIL induces proliferation in rodent pancreatic beta cells through activation of the AKT pathway.

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Regulation of Pancreatic Beta-Cell Mass

Physiological Reviews ◽

10.1152/physrev.00025.2004 ◽

2005 ◽

Vol 85 (4) ◽

pp. 1255-1270 ◽

Cited By ~ 248

Author(s):

Luc Bouwens ◽

Ilse Rooman

Keyword(s):

Beta Cell ◽

Progenitor Cells ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Tissue Injury ◽

Pancreatic Beta Cell ◽

Cell Mass ◽

Beta Cell Mass ◽

Cell Number ◽

External Stimuli

Beta-cell mass regulation represents a critical issue for understanding diabetes, a disease characterized by a near-absolute (type 1) or relative (type 2) deficiency in the number of pancreatic beta cells. The number of islet beta cells present at birth is mainly generated by the proliferation and differentiation of pancreatic progenitor cells, a process called neogenesis. Shortly after birth, beta-cell neogenesis stops and a small proportion of cycling beta cells can still expand the cell number to compensate for increased insulin demands, albeit at a slow rate. The low capacity for self-replication in the adult is too limited to result in a significant regeneration following extensive tissue injury. Likewise, chronically increased metabolic demands can lead to beta-cell failure to compensate. Neogenesis from progenitor cells inside or outside islets represents a more potent mechanism leading to robust expansion of the beta-cell mass, but it may require external stimuli. For therapeutic purposes, advantage could be taken from the surprising differentiation plasticity of adult pancreatic cells and possibly also from stem cells. Recent studies have demonstrated that it is feasible to regenerate and expand the beta-cell mass by the application of hormones and growth factors like glucagon-like peptide-1, gastrin, epidermal growth factor, and others. Treatment with these external stimuli can restore a functional beta-cell mass in diabetic animals, but further studies are required before it can be applied to humans.

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