Overexpression of Pre-Pro-Cholecystokinin Stimulates β-Cell Proliferation in Mouse and Human Islets with Retention of Islet Function

AbstractTranscriptionally mature and immature β-cells co-exist within the adult islet. How such diversity contributes to insulin release remains poorly understood. Here we show that subtle differences in β-cell maturity, defined using PDX1 and MAFA expression, contribute to islet operation. Functional mapping of rodent and human islets containing proportionally more PDX1HIGH and MAFAHIGH β-cells reveals defects in metabolism, ionic fluxes and insulin secretion. At the transcriptomic level, the presence of increased numbers of PDX1HIGH and MAFAHIGH β-cells leads to dysregulation of gene pathways involved in metabolic processes. Using a chemogenetic disruption strategy, differences in PDX1 and MAFA expression are shown to depend on islet Ca2+ signaling patterns. During metabolic stress, islet function can be restored by redressing the balance between PDX1 and MAFA levels across the β-cell population. Thus, preserving heterogeneity in PDX1 and MAFA expression, and more widely in β-cell maturity, might be important for the maintenance of islet function.

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The regulator of G-protein signaling RGS16 promotes insulin secretion and β-cell proliferation in rodent and human islets

Molecular Metabolism ◽

10.1016/j.molmet.2016.08.010 ◽

2016 ◽

Vol 5 (10) ◽

pp. 988-996 ◽

Cited By ~ 14

Author(s):

Kevin Vivot ◽

Valentine S. Moullé ◽

Bader Zarrouki ◽

Caroline Tremblay ◽

Arturo D. Mancini ◽

...

Keyword(s):

Cell Proliferation ◽

Insulin Secretion ◽

G Protein ◽

Human Islets ◽

G Protein Signaling ◽

Protein Signaling ◽

Β Cell

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The Transcription Factor Nfatc2 Regulates β-Cell Proliferation and Genes Associated with Type 2 Diabetes in Mouse and Human Islets

PLoS Genetics ◽

10.1371/journal.pgen.1006466 ◽

2016 ◽

Vol 12 (12) ◽

pp. e1006466 ◽

Cited By ~ 10

Author(s):

Mark P. Keller ◽

Pradyut K. Paul ◽

Mary E. Rabaglia ◽

Donnie S. Stapleton ◽

Kathryn L. Schueler ◽

...

Keyword(s):

Type 2 Diabetes ◽

Cell Proliferation ◽

Transcription Factor ◽

Human Islets ◽

Β Cell

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The diabetes-linked transcription factor PAX4 promotes β-cell proliferation and survival in rat and human islets

The Journal of Cell Biology ◽

10.1083/jcb.200405148 ◽

2004 ◽

Vol 167 (6) ◽

pp. 1123-1135 ◽

Cited By ~ 97

Author(s):

Thierry Brun ◽

Isobel Franklin ◽

Luc St-Onge ◽

Anna Biason-Lauber ◽

Eugene J. Schoenle ◽

...

Keyword(s):

Cell Proliferation ◽

Transcription Factor ◽

Cell Function ◽

Fold Increase ◽

Human Islets ◽

Mrna Levels ◽

Phosphatidylinositol 3 Kinase ◽

Β Cell ◽

Atp Production ◽

Adult Rat

The mechanism by which the β-cell transcription factor Pax4 influences cell function/mass was studied in rat and human islets of Langerhans. Pax4 transcripts were detected in adult rat islets, and levels were induced by the mitogens activin A and betacellulin. Wortmannin suppressed betacellulin-induced Pax4 expression, implicating the phosphatidylinositol 3-kinase signaling pathway. Adenoviral overexpression of Pax4 caused a 3.5-fold increase in β-cell proliferation with a concomitant 1.9-, 4-, and 5-fold increase in Bcl-xL (antiapoptotic), c-myc, and Id2 mRNA levels, respectively. Accordingly, Pax4 transactivated the Bcl-xL and c-myc promoters, whereas its diabetes-linked mutant was less efficient. Bcl-xL activity resulted in altered mitochondrial calcium levels and ATP production, explaining impaired glucose-induced insulin secretion in transduced islets. Infection of human islets with an inducible adenoviral Pax4 construct caused proliferation and protection against cytokine-evoked apoptosis, whereas the mutant was less effective. We propose that Pax4 is implicated in β-cell plasticity through the activation of c-myc and potentially protected from apoptosis through Bcl-xL gene expression.

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The cannabinoid ligands SR141716A and AM251 enhance human and mouse islet function via GPR55-independent signalling

Cellular and Molecular Life Sciences ◽

10.1007/s00018-019-03433-6 ◽

2020 ◽

Vol 77 (22) ◽

pp. 4709-4723 ◽

Cited By ~ 3

Author(s):

Inmaculada Ruz-Maldonado ◽

Bo Liu ◽

Patricio Atanes ◽

Attilio Pingitore ◽

Guo Cai Huang ◽

...

Keyword(s):

Cell Proliferation ◽

Insulin Secretion ◽

Cannabinoid Receptors ◽

Cannabinoid Receptor ◽

Cell Types ◽

Islet Function ◽

Receptor Ligands ◽

Β Cell ◽

Beneficial Effects

Abstract Aims Endocannabinoids are lipid mediators involved in the regulation of glucose homeostasis. They interact with the canonical cannabinoid receptors CB1 and CB2, and it is now apparent that some cannabinoid receptor ligands are also agonists at GPR55. Thus, CB1 antagonists such as SR141716A, also known as rimonabant, and AM251 act as GPR55 agonists in some cell types. The complex pharmacological properties of cannabinoids make it difficult to fully identify the relative importance of CB1 and GPR55 in the functional effects of SR141716A, and AM251. Here, we determine whether SR141716A and AM251 regulation of mouse and human islet function is through their action as GPR55 agonists. Methods Islets isolated from Gpr55+/+ and Gpr55−/− mice and human donors were incubated in the absence or presence of 10 µM SR141716A or AM251, concentrations that are known to activate GPR55. Insulin secretion, cAMP, IP1, apoptosis and β-cell proliferation were quantified by standard techniques. Results Our results provide the first evidence that SR141716A and AM251 are not GPR55 agonists in islets, as their effects are maintained in islets isolated from Gpr55−/− mice. Their signalling through Gq-coupled cascades to induce insulin secretion and human β-cell proliferation, and protect against apoptosis in vitro, indicate that they have direct beneficial effects on islet function. Conclusion These observations may be useful in directing development of peripherally restricted novel therapeutics that are structurally related to SR141716A and AM251, and which potentiate glucose-induced insulin secretion and stimulate β-cell proliferation.

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Genistein Induces Pancreatic β-Cell Proliferation through Activation of Multiple Signaling Pathways and Prevents Insulin-Deficient Diabetes in Mice

Endocrinology ◽

10.1210/en.2009-1294 ◽

2010 ◽

Vol 151 (7) ◽

pp. 3026-3037 ◽

Cited By ~ 124

Author(s):

Zhuo Fu ◽

Wen Zhang ◽

Wei Zhen ◽

Hazel Lum ◽

Jerry Nadler ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Function ◽

Herbal Medicines ◽

Human Islets ◽

Pancreatic Β Cell ◽

Diabetic Mice ◽

Β Cell ◽

Β Cell Function ◽

17Β Estradiol ◽

Multiple Signaling

Genistein, a flavonoid in legumes and some herbal medicines, has various biological actions. However, studies on whether genistein has an effect on pancreatic β-cell function are very limited. In the present study, we investigated the effect of genistein on β-cell proliferation and cellular signaling related to this effect and further determined its antidiabetic potential in insulin-deficient diabetic mice. Genistein induced both INS1 and human islet β-cell proliferation after 24 h of incubation, with 5 μm genistein inducing a maximal 27% increase. The effect of genistein on β-cell proliferation was neither dependent on estrogen receptors nor shared by 17β-estradiol or a host of structurally related flavonoid compounds. Pharmacological or molecular intervention of protein kinase A (PKA) or ERK1/2 completely abolished genistein-stimulated β-cell proliferation, suggesting that both molecules are essential for genistein action. Consistent with its effect on cell proliferation, genistein induced cAMP/PKA signaling and subsequent phosphorylation of ERK1/2 in both INS1 cells and human islets. Furthermore, genistein induced protein expression of cyclin D1, a major cell-cycle regulator essential for β-cell growth. Dietary intake of genistein significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in streptozotocin-induced diabetic mice, concomitant with improved islet β-cell proliferation, survival, and mass. These results demonstrate that genistein may be a natural antidiabetic agent by directly modulating pancreatic β-cell function via activation of the cAMP/PKA-dependent ERK1/2 signaling pathway.

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DYRK1A Kinase Inhibitors Promote β-Cell Survival and Insulin Homeostasis

Cells ◽

10.3390/cells10092263 ◽

2021 ◽

Vol 10 (9) ◽

pp. 2263

Author(s):

Agata Barzowska ◽

Barbara Pucelik ◽

Katarzyna Pustelny ◽

Alex Matsuda ◽

Alicja Martyniak ◽

...

Keyword(s):

Cell Proliferation ◽

Small Molecule ◽

Kinase Inhibitors ◽

Human Islets ◽

Β Cell ◽

Insulin Homeostasis ◽

Current Therapies ◽

Comparable Activity ◽

Human Ipsc

The rising prevalence of diabetes is threatening global health. It is known not only for the occurrence of severe complications but also for the SARS-Cov-2 pandemic, which shows that it exacerbates susceptibility to infections. Current therapies focus on artificially maintaining insulin homeostasis, and a durable cure has not yet been achieved. We demonstrate that our set of small molecule inhibitors of DYRK1A kinase potently promotes β-cell proliferation, enhances long-term insulin secretion, and balances glucagon level in the organoid model of the human islets. Comparable activity is seen in INS-1E and MIN6 cells, in isolated mice islets, and human iPSC-derived β-cells. Our compounds exert a significantly more pronounced effect compared to harmine, the best-documented molecule enhancing β-cell proliferation. Using a body-like environment of the organoid, we provide a proof-of-concept that small–molecule–induced human β-cell proliferation via DYRK1A inhibition is achievable, which lends a considerable promise for regenerative medicine in T1DM and T2DM treatment.

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Cyclin C stimulates β-cell proliferation in rat and human pancreatic β-cells

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00260.2014 ◽

2015 ◽

Vol 308 (6) ◽

pp. E450-E459 ◽

Cited By ~ 3

Author(s):

Margarita Jiménez-Palomares ◽

José Francisco López-Acosta ◽

Pablo Villa-Pérez ◽

José Luis Moreno-Amador ◽

Jennifer Muñoz-Barrera ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Death ◽

Cell Function ◽

Cell Mass ◽

Human Islets ◽

Brdu Incorporation ◽

Pancreatic Β Cell ◽

Β Cell ◽

Cyclin C ◽

Β Cell Function

Activation of pancreatic β-cell proliferation has been proposed as an approach to replace reduced functional β-cell mass in diabetes. Quiescent fibroblasts exit from G0 (quiescence) to G1 through pRb phosphorylation mediated by cyclin C/cdk3 complexes. Overexpression of cyclin D1, D2, D3, or cyclin E induces pancreatic β-cell proliferation. We hypothesized that cyclin C overexpression would induce β-cell proliferation through G0 exit, thus being a potential therapeutic target to recover functional β-cell mass. We used isolated rat and human islets transduced with adenovirus expressing cyclin C. We measured multiple markers of proliferation: [3H]thymidine incorporation, BrdU incorporation and staining, and Ki67 staining. Furthermore, we detected β-cell death by TUNEL, β-cell differentiation by RT-PCR, and β-cell function by glucose-stimulated insulin secretion. Interestingly, we have found that cyclin C increases rat and human β-cell proliferation. This augmented proliferation did not induce β-cell death, dedifferentiation, or dysfunction in rat or human islets. Our results indicate that cyclin C is a potential target for inducing β-cell regeneration.

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TGF-β Superfamily Member Nodal Stimulates Human β-Cell Proliferation While Maintaining Cellular Viability

Endocrinology ◽

10.1210/en.2013-1197 ◽

2013 ◽

Vol 154 (11) ◽

pp. 4099-4112 ◽

Cited By ~ 13

Author(s):

Brian P. Boerner ◽

Nicholas M. George ◽

Natalie M. Targy ◽

Nora E. Sarvetnick

Keyword(s):

Cell Proliferation ◽

Protein Expression ◽

Cell Types ◽

Mapk Signaling ◽

Human Islets ◽

Human Pancreas ◽

Cellular Viability ◽

Β Cell ◽

Mrna And Protein Expression ◽

Insulinoma Cells

In an effort to expand human islets and enhance allogeneic islet transplant for the treatment of type 1 diabetes, identifying signaling pathways that stimulate human β-cell proliferation is paramount. TGF-β superfamily members, in particular activin-A, are likely involved in islet development and may contribute to β-cell proliferation. Nodal, another TGF-β member, is present in both embryonic and adult rodent islets. Nodal, along with its coreceptor, Cripto, are pro-proliferative factors in certain cell types. Although Nodal stimulates apoptosis of rat insulinoma cells (INS-1), Nodal and Cripto signaling have not been studied in the context of human islets. The current study investigated the effects of Nodal and Cripto on human β-cell proliferation, differentiation, and viability. In the human pancreas and isolated human islets, we observed Nodal mRNA and protein expression, with protein expression observed in β and α-cells. Cripto expression was absent from human islets. Furthermore, in cultured human islets, exogenous Nodal stimulated modest β-cell proliferation and inhibited α-cell proliferation with no effect on cellular viability, apoptosis, or differentiation. Nodal stimulated the phosphorylation of mothers against decapentaplegic (SMAD)-2, with no effect on AKT or MAPK signaling, suggesting phosphorylated SMAD signaling was involved in β-cell proliferation. Cripto had no effect on human islet cell proliferation, differentiation, or viability. In conclusion, Nodal stimulates human β-cell proliferation while maintaining cellular viability. Nodal signaling warrants further exploration to better understand and enhance human β-cell proliferative capacity.

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Combined use of GABA and sitagliptin promotes human β-cell proliferation and reduces apoptosis

Journal of Endocrinology ◽

10.1530/joe-20-0315 ◽

2020 ◽

Author(s):

Wenjuan Liu ◽

Harry Kevin Lau ◽

Dong Ok Son ◽

Tianru Jin ◽

Yehong Yang ◽

...

Keyword(s):

Cell Proliferation ◽

Human Islets ◽

Β Cells ◽

Β Cell ◽

Dipeptidyl Peptidase 4 ◽

Glucose Levels ◽

Cell Counts ◽

Therapeutic Benefits ◽

Combined Use ◽

Glucagon Like Peptide 1

γ-aminobutyric acid (GABA) and glucagon-like peptide-1 receptor agonist (GLP-1RA) improve rodent β-cell survival and function. In human β-cells, GABA exerts stimulatory effects on proliferation and anti-apoptotic effects, whereas GLP-1RA drugs have only limited effects on proliferation. We previously demonstrated that GABA and sitagliptin (Sita), a dipeptidyl peptidase-4 inhibitor which increases endogenous GLP-1 levels, mediated a synergistic β-cell protective effect in mice islets. However, it remains unclear whether this combination has similar effects on human β-cell. To address this question, we transplanted a suboptimal mass of human islets into immunodeficient NOD-scid-gamma mice with streptozotocin-induced diabetes, and then treated them with GABA, Sita, or both. The oral administration of either GABA or Sita ameliorated blood glucose levels, increased transplanted human β-cell counts and plasma human insulin levels. Importantly, combined administration of the drugs generated significantly superior results in all these responses, as compared to the monotherapy with either one of them. Proliferation and/or regeneration, improved by the combination, were demonstrated by increased Ki67+, PDX-1+, or Nkx6.1+ β-cell numbers. Protection against apoptosis was also significantly improved by the drug combination. The expression level of α-Klotho, a protein with protective and stimulatory effects on β cells, was also augmented. Our study indicates that combined use of GABA and Sita produced greater therapeutic benefits, which are likely due to an enhancement of β-cell proliferation and a decrease in apoptosis.

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