Glucose-stimulated calcium dynamics in beta cells from C57BL/6J, C57BL/6N, and NMRI mice: A systematic comparison of activation, activity, and deactivation properties in tissue slices

Although mice are a very instrumental model in islet beta cell research, possible phenotypic differences between strains and substrains are largely neglected in the scientific community. In this study, we show important phenotypic differences in beta cell responses to glucose between NMRI, C57BL/6J, and C57BL/6N mice, i.e., the three most commonly used strains. High-resolution multicellular confocal imaging of beta cells in acute pancreas tissue slices was used to measure and quantitatively compare the calcium dynamics in response to a wide range of glucose concentrations. Strain- and substrain-specific features were found in all three phases of beta cell responses to glucose: a shift in the dose-response curve characterizing the delay to activation and deactivation in response to stimulus onset and termination, respectively, and distinct concentration-encoding principles during the plateau phase in terms of frequency, duration, and active time changes with increasing glucose concentrations. Our results underline the significance of carefully choosing and reporting the strain to enable comparison and increase reproducibility, emphasize the importance of analyzing a number of different beta cell physiological parameters characterizing the response to glucose, and provide a valuable standard for future studies on beta cell calcium dynamics in health and disease.

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The Relationship between Membrane Potential and Calcium Dynamics in Glucose-Stimulated Beta Cell Syncytium in Acute Mouse Pancreas Tissue Slices

PLoS ONE ◽

10.1371/journal.pone.0082374 ◽

2013 ◽

Vol 8 (12) ◽

pp. e82374 ◽

Cited By ~ 35

Author(s):

Jurij Dolenšek ◽

Andraž Stožer ◽

Maša Skelin Klemen ◽

Evan W. Miller ◽

Marjan Slak Rupnik

Keyword(s):

Membrane Potential ◽

Beta Cell ◽

Calcium Dynamics ◽

Tissue Slices ◽

Mouse Pancreas ◽

The Relationship

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Membrane Potential and Calcium Dynamics in Beta Cells from Mouse Pancreas Tissue Slices: Theory, Experimentation, and Analysis

Sensors ◽

10.3390/s151127393 ◽

2015 ◽

Vol 15 (11) ◽

pp. 27393-27419 ◽

Cited By ~ 5

Author(s):

Jurij Dolenšek ◽

Denis Špelič ◽

Maša Klemen ◽

Borut Žalik ◽

Marko Gosak ◽

...

Keyword(s):

Membrane Potential ◽

Beta Cells ◽

Calcium Dynamics ◽

Tissue Slices ◽

Mouse Pancreas

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Glucose-dependent activation, activity, and deactivation of beta cell networks in acute mouse pancreas tissue slices

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00043.2021 ◽

2021 ◽

Author(s):

Andraz Stozer ◽

Maša Skelin Klemen ◽

Marko Gosak ◽

Lidija Križančić Bombek ◽

Viljem Pohorec ◽

...

Keyword(s):

Beta Cell ◽

Common Ground ◽

Calcium Oscillations ◽

Tissue Slices ◽

Mouse Pancreas ◽

Functional Connections ◽

Wide Range ◽

Network Properties ◽

Beta Cell Heterogeneity ◽

Cell Networks

Many details of glucose-stimulated intracellular calcium changes in beta cells during activation, activity, and deactivation, as well as their concentration-dependence, remain to be analyzed. Classical physiological experiments indicated that in islets, functional differences between individual cells are largely attenuated, but recent findings suggest considerable intercellular heterogeneity, with some cells possibly coordinating the collective responses. To address the above with an emphasis on heterogeneity and describing the relations between classical physiological and functional network properties, we performed functional multicellular calcium imaging in mouse pancreas tissue slices over a wide range of glucose concentrations. During activation, delays to activation of cells and any-cell-to-first-responder delays shortened, and the sizes of simultaneously responding clusters increased with increasing glucose. Exactly the opposite characterized deactivation. The frequency of fast calcium oscillations during activity increased with increasing glucose up to 12 mM glucose, beyond which oscillation duration became longer, resulting in a homogenous increase in active time. In terms of functional connectivity, islets progressed from a very segregated network to a single large functional unit with increasing glucose. A comparison between classical physiological and network parameters revealed that the first-responders during activation had longer active times during plateau and the most active cells during the plateau tended to deactivate later. Cells with the most functional connections tended to activate sooner, have longer active times, and deactivate later. Our findings provide a common ground for recent differing views on beta cell heterogeneity and an important baseline for future studies of stimulus-secretion and intercellular coupling.

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Glucose-dependent activation, activity, and deactivation of beta cell networks in acute mouse pancreas tissue slices

10.1101/2020.03.11.986893 ◽

2020 ◽

Author(s):

Jurij Dolenšek ◽

Maša Skelin Klemen ◽

Marko Gosak ◽

Lidija Križančić-Bombek ◽

Viljem Pohorec ◽

...

Keyword(s):

Beta Cell ◽

Beta Cells ◽

Insulin Release ◽

Glucose Concentration ◽

Calcium Oscillations ◽

Tissue Slices ◽

Mouse Pancreas ◽

Network Parameters ◽

Cell Networks ◽

Glucose Dependence

AbstractGlucose progressively stimulates insulin release over a wide range of concentrations. However, the nutrient coding underlying activation, activity, and deactivation of beta cells affecting insulin release remains only partially described. Experimental data indicate that nutrient sensing in coupled beta cells in islets is predominantly a collective trait, overriding to a large extent functional differences between cells. However, some degree of heterogeneity between coupled beta cells may play important roles. To further elucidate glucose-dependent modalities in coupled beta cells, the degree of functional heterogeneity, and uncover the emergent collective operations, we combined acute mouse pancreas tissue slices with functional multicellular calcium imaging. We recorded beta cell calcium responses from threshold (7 mM) to supraphysiological (16 mM) glucose concentrations with high spatial and temporal resolution. This enabled the analysis of both classical physiological parameters and complex network parameters, as well as their comparison at the level of individual cells. The activation profile displayed two major glucose concentration-dependent features, shortening of delays to initial activation, and shortening of delays until half activation with increasing glucose concentration. Inversely, during deactivation both delays to initial deactivation and until half deactivation were progressively longer with increasing glucose concentration. The plateau activity with fast calcium oscillations expressed two types of glucose-dependence. Physiological concentrations mostly affected the frequency of oscillations, whereas supraphysiological concentrations progressively prolonged the duration of oscillations. Most of the measured functional network parameters also showed clear glucose-dependence. In conclusion, we propose novel understanding for glucose-dependent coding properties in beta cell networks, and its deciphering may have repercussions for our understanding of the normal physiology of glucose homeostasis as well as of disturbances of metabolic homeostasis, such as diabetes mellitus.

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Fibroblast growth factor receptor 5 (FGFR5) is a co-receptor for FGFR1 that is up-regulated in beta-cells by cytokine-induced inflammation

Journal of Biological Chemistry ◽

10.1074/jbc.ra118.003036 ◽

2018 ◽

Vol 293 (44) ◽

pp. 17218-17228 ◽

Cited By ~ 5

Author(s):

Romario Regeenes ◽

Pamuditha N. Silva ◽

Huntley H. Chang ◽

Edith J. Arany ◽

Andrey I. Shukalyuk ◽

...

Keyword(s):

Plasma Membrane ◽

Growth Factor ◽

Beta Cell ◽

Cell Survival ◽

Fibroblast Growth Factor ◽

Beta Cells ◽

Fibroblast Growth Factor Receptor ◽

Growth Factor Receptor ◽

Fibroblast Growth ◽

Wide Range

Fibroblast growth factor receptor-1 (FGFR1) activity at the plasma membrane is tightly controlled by the availability of co-receptors and competing receptor isoforms. We have previously shown that FGFR1 activity in pancreatic beta-cells modulates a wide range of processes, including lipid metabolism, insulin processing, and cell survival. More recently, we have revealed that co-expression of FGFR5, a receptor isoform that lacks a tyrosine-kinase domain, influences FGFR1 responses. We therefore hypothesized that FGFR5 is a co-receptor to FGFR1 that modulates responses to ligands by forming a receptor heterocomplex with FGFR1. We first show here increased FGFR5 expression in the pancreatic islets of nonobese diabetic (NOD) mice and also in mouse and human islets treated with proinflammatory cytokines. Using siRNA knockdown, we further report that FGFR5 and FGFR1 expression improves beta-cell survival. Co-immunoprecipitation and quantitative live-cell imaging to measure the molecular interaction between FGFR5 and FGFR1 revealed that FGFR5 forms a mixture of ligand-independent homodimers (∼25%) and homotrimers (∼75%) at the plasma membrane. Interestingly, co-expressed FGFR5 and FGFR1 formed heterocomplexes with a 2:1 ratio and subsequently responded to FGF2 by forming FGFR5/FGFR1 signaling complexes with a 4:2 ratio. Taken together, our findings identify FGFR5 as a co-receptor that is up-regulated by inflammation and promotes FGFR1-induced survival, insights that reveal a potential target for intervention during beta-cell pathogenesis.

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Correlations between beta-cells' calcium dynamics reveal differences in functional connectivity patterns in islets of Langerhans from pancreas tissue slices under low and high levels of glucose

10.1063/1.4745592 ◽

2012 ◽

Author(s):

Andraž Stožer ◽

Marko Gosak ◽

Dean Korošak ◽

Kousuke Yakubo ◽

Jure Dolenšek ◽

...

Keyword(s):

Functional Connectivity ◽

Beta Cells ◽

Islets Of Langerhans ◽

Calcium Dynamics ◽

Tissue Slices ◽

Connectivity Patterns

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FSTL3 Neutralizing Antibodies Enhance Glucose-Responsive Insulin Secretion In Dysfunctional Male Mouse And Human Islets

Endocrinology ◽

10.1210/endocr/bqab019 ◽

2021 ◽

Author(s):

Melissa L Brown ◽

Alexa Lopez ◽

Nolan Meyer ◽

Alden Richter ◽

Thomas B Thompson

Keyword(s):

Insulin Secretion ◽

Beta Cell ◽

Beta Cells ◽

Pancreatic Beta Cells ◽

Neutralizing Antibodies ◽

Cell Number ◽

Human Islets ◽

In Vitro Assays ◽

Insulin Production ◽

Wide Range

Abstract Diabetes is caused by insufficient insulin production from pancreatic beta cells or insufficient insulin action leading to an inability to control blood glucose. While a wide range of treatments exist to alleviate the symptoms of diabetes, therapies addressing the root cause of diabetes through replacing lost beta cells with functional cells remain an active pursuit. We previously demonstrated that genetic deletion of Fstl3, a critical regulator of activin activity, enhanced beta cell number and glucose-responsive insulin production. These observations suggested the hypothesis that FSTL3 neutralization could be used to therapeutically enhance beta cell number and function in humans. To pursue this possibility, we developed an FSTL3 neutralizing antibody, FP-101, and characterized its ability to prevent or disrupt FSTL3 from complexing with activin or related ligands. This antibody was selective for FSTL3 relative to the closely related follistatin thereby reducing the chance for off-target effects. In vitro assays with FP-101 and activin revealed that FP-101-mediated neutralization of FSTL3 can enhance both insulin secretion and glucose responsiveness to non-functional mouse and human islets under conditions that model diabetes. Thus, FSTL3 neutralization may provide a novel therapeutic strategy for treating diabetes through repairing dysfunctional beta cells.

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Faculty Opinions recommendation of Conversion of adult pancreatic alpha-cells to beta-cells after extreme beta-cell loss.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.3025957.2738058 ◽

2010 ◽

Author(s):

Sarah Ferber ◽

Irit Meivar-Levy

Keyword(s):

Beta Cell ◽

Beta Cells ◽

Cell Loss ◽

Alpha Cells ◽

Pancreatic Alpha Cells

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Effects of Extra Virgin Olive Oil Polyphenols on Beta-Cell Function and Survival

Plants ◽

10.3390/plants10020286 ◽

2021 ◽

Vol 10 (2) ◽

pp. 286

Author(s):

Nicola Marrano ◽

Rosaria Spagnuolo ◽

Giuseppina Biondi ◽

Angelo Cignarelli ◽

Sebastio Perrini ◽

...

Keyword(s):

Insulin Secretion ◽

Beta Cell ◽

Olive Oil ◽

Beta Cells ◽

Intracellular Signaling ◽

Beta Cell Function ◽

Cell Function ◽

Virgin Olive Oil ◽

Extra Virgin Olive Oil ◽

Insulin Biosynthesis

Extra virgin olive oil (EVOO) is a major component of the Mediterranean diet and is appreciated worldwide because of its nutritional benefits in metabolic diseases, including type 2 diabetes (T2D). EVOO contains significant amounts of secondary metabolites, such as phenolic compounds (PCs), that may positively influence the metabolic status. In this study, we investigated for the first time the effects of several PCs on beta-cell function and survival. To this aim, INS-1E cells were exposed to 10 μM of the main EVOO PCs for up to 24 h. Under these conditions, survival, insulin biosynthesis, glucose-stimulated insulin secretion (GSIS), and intracellular signaling activation (protein kinase B (AKT) and cAMP response element-binding protein (CREB)) were evaluated. Hydroxytyrosol, tyrosol, and apigenin augmented beta-cell proliferation and insulin biosynthesis, and apigenin and luteolin enhanced the GSIS. Conversely, vanillic acid and vanillin were pro-apoptotic for beta-cells, even if they increased the GSIS. In addition, oleuropein, p-coumaric, ferulic and sinapic acids significantly worsened the GSIS. Finally, a mixture of hydroxytyrosol, tyrosol, and apigenin promoted the GSIS in human pancreatic islets. Apigenin was the most effective compound and was also able to activate beneficial intracellular signaling. In conclusion, this study shows that hydroxytyrosol, tyrosol, and apigenin foster beta-cells’ health, suggesting that EVOO or supplements enriched with these compounds may improve insulin secretion and promote glycemic control in T2D patients.

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