scholarly journals Arid1a loss potentiates pancreatic β-cell regeneration through activation of EGF signaling

2020 ◽  
Author(s):  
Cemre Celen ◽  
Jen-Chieh Chuang ◽  
Shunli Shen ◽  
Jordan E. Otto ◽  
Clayton K. Collings ◽  
...  

SummaryThe dynamic regulation of β-cell abundance is poorly understood. Since chromatin remodeling plays critical roles in liver regeneration, these mechanisms could be generally important for regeneration in other tissues. Here we show that the ARID1A mammalian SWI/SNF complex subunit is a critical regulator of β-cell regeneration. Arid1a is highly expressed in quiescent β-cells but is physiologically suppressed when β-cells proliferate during pregnancy or after pancreas resection. Whole-body Arid1a knockout mice were protected against streptozotocin induced diabetes. Cell-type and temporally specific genetic dissection showed that β-cell specific Arid1a deletion could potentiate β-cell regeneration in multiple contexts. Transcriptomic and epigenomic profiling of mutant islets revealed increased Neuregulin-ERBB-NR4A signaling. Functionally, ERBB3 overexpression in β-cells was sufficient to protect against diabetes, and chemical inhibition of ERBB or NR4A was able to block increased regeneration associated with Arid1a loss. mSWI/SNF complex activity is a barrier to β-cell regeneration in physiologic and disease states.

2021 ◽  
Vol 2021 ◽  
pp. 1-32
Author(s):  
Akurange Sujeevi Dammadinna Wickramasinghe ◽  
Pabasara Kalansuriya ◽  
Anoja Priyadarshani Attanayake

There is an increasing trend of investigating natural bioactive compounds targeting pancreatic β-cells for the prevention/treatment of diabetes mellitus (DM). With the exploration of multiple mechanisms by which β-cells involve in the pathogenesis of DM, herbal medicines are gaining attention due to their multitasking ability as evidenced by traditional medicine practices. This review attempts to summarize herbal medicines with the potential for improvement of β-cell functions and regeneration as scientifically proven by in vivo/in vitro investigations. Furthermore, attempts have been made to identify the mechanisms of improving the function and regeneration of β-cells by herbal medicines. Relevant data published from January 2009 to March 2020 were collected by searching electronic databases “PubMed,” “ScienceDirect,” and “Google Scholar” and studied for this review. Single herbal extracts, polyherbal mixtures, and isolated compounds derived from approximately 110 medicinal plants belonging to 51 different plant families had been investigated in recent years and found to be targeting β-cells. Many herbal medicines showed improvement of β-cell function as observed through homeostatic model assessment-β-cell function (HOMA-β). Pancreatic β-cell regeneration as observed in histopathological and immunohistochemical studies in terms of increase of size and number of functional β-cells was also prominent. Increasing β-cell mass via expression of genes/proteins related to antiapoptotic actions and β-cell neogenesis/proliferation, increasing glucose-stimulated insulin secretion via activating glucose transporter-2 (GLUT-2) receptors, and/or increasing intracellular Ca2+ levels were observed upon treatment of some herbal medicines. Some herbal medicines acted on various insulin signaling pathways. Furthermore, many herbal medicines showed protective effects on β-cells via reduction of oxidative stress and inflammation. However, there are many unexplored avenues. Thus, further investigations are warranted in elucidating mechanisms of improving β-cell function and mass by herbal medicines, their structure-activity relationship (SAR), and toxicities of these herbal medicines.


2006 ◽  
Vol 26 (7) ◽  
pp. 2772-2781 ◽  
Author(s):  
Bangyan L. Stiles ◽  
Christine Kuralwalla-Martinez ◽  
Wei Guo ◽  
Caroline Gregorian ◽  
Ying Wang ◽  
...  

ABSTRACT Phosphatase and tensin homologue deleted on chromosome 10 (PTEN) is a lipid phosphatase. PTEN inhibits the action of phosphatidylinositol-3-kinase and reduces the levels of phosphatidylinositol triphosphate, a crucial second messenger for cell proliferation and survival, as well as insulin signaling. In this study, we deleted Pten specifically in the insulin producing β cells during murine pancreatic development. Pten deletion leads to increased cell proliferation and decreased cell death, without significant alteration of β-cell differentiation. Consequently, the mutant pancreas generates more and larger islets, with a significant increase in total β-cell mass. PTEN loss also protects animals from developing streptozotocin-induced diabetes. Our data demonstrate that PTEN loss in β cells is not tumorigenic but beneficial. This suggests that modulating the PTEN-controlled signaling pathway is a potential approach for β-cell protection and regeneration therapies.


2009 ◽  
Vol 297 (2) ◽  
pp. E323-E330 ◽  
Author(s):  
Erica Manesso ◽  
Gianna M. Toffolo ◽  
Yoshifumi Saisho ◽  
Alexandra E. Butler ◽  
Aleksey V. Matveyenko ◽  
...  

Type 2 diabetes is characterized by hyperglycemia, a deficit in β-cells, increased β-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). These characteristics are recapitulated in the human IAPP transgenic (HIP) rat. We developed a mathematical model to quantify β-cell turnover and applied it to nondiabetic wild type (WT) vs. HIP rats from age 2 days to 10 mo to establish 1) whether β-cell formation is derived exclusively from β-cell replication, or whether other sources of β-cells (OSB) are present, and 2) to what extent, if any, there is attempted β-cell regeneration in the HIP rat and if this is through β-cell replication or OSB. We conclude that formation and maintenance of adult β-cells depends largely (∼80%) on formation of β-cells independent from β-cell duplication. Moreover, this source adaptively increases in the HIP rat, implying attempted β-cell regeneration that substantially slows loss of β-cell mass.


Author(s):  
Young-Sun Lee ◽  
Gyun Jee Song ◽  
Hee-Sook Jun

Betacellulin (BTC), an epidermal growth factor family, is known to promote β-cell regeneration. Recently, pancreatic α-cells have been highlighted as a source of new β-cells. We investigated the effect of BTC on α-cells. Insulin+glucagon+ double stained bihormonal cell levels and pancreatic and duodenal homeobox-1 expression were increased in mice treated with recombinant adenovirus-expressing BTC (rAd-BTC) and β-cell-ablated islet cells treated with BTC. In the islets of rAd-BTC-treated mice, both BrdU+glucagon+ and BrdU+insulin+ cell levels were significantly increased, with BrdU+glucagon+ cells showing the greater increase. Treatment of αTC1-9 cells with BTC significantly increased proliferation and cyclin D2 expression. BTC induced phosphorylation of ErbB receptors in αTC1-9 cells. The proliferative effect of BTC was mediated by ErbB-3 or ErbB-4 receptor kinase. BTC increased phosphorylation of ERK1/2, AKT, and mTOR and PC1/3 expression and GLP-1 production in α-cells, but BTC-induced proliferation was not changed by the GLP-1 receptor antagonist, exendin-9. We suggest that BTC has a direct role in α-cell proliferation via interaction with ErbB-3 and ErbB-4 receptors, and these increased α-cells might be a source of new β-cells.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Ka-Cheuk Liu ◽  
Alethia Villasenor ◽  
Maria Bertuzzi ◽  
Nicole Schmitner ◽  
Niki Radros ◽  
...  

To investigate the role of the vasculature in pancreatic β-cell regeneration, we crossed a zebrafish β-cell ablation model into the avascular npas4l mutant (i.e. cloche). Surprisingly, β-cell regeneration increased markedly in npas4l mutants owing to the ectopic differentiation of β-cells in the mesenchyme, a phenotype not previously reported in any models. The ectopic β-cells expressed endocrine markers of pancreatic β-cells, and also responded to glucose with increased calcium influx. Through lineage tracing, we determined that the vast majority of these ectopic β-cells has a mesodermal origin. Notably, ectopic β-cells were found in npas4l mutants as well as following knockdown of the endothelial/myeloid determinant Etsrp. Together, these data indicate that under the perturbation of endothelial/myeloid specification, mesodermal cells possess a remarkable plasticity enabling them to form β-cells, which are normally endodermal in origin. Understanding the restriction of this differentiation plasticity will help exploit an alternative source for β-cell regeneration.


2021 ◽  
Author(s):  
Byung-Jun Sung ◽  
Sung-Bin Lim ◽  
Jae Hyeon Kim ◽  
Won-Mo Yang ◽  
Rohit N Kulkarni ◽  
...  

Objective: The endocrine pancreatic β-cells play a pivotal role in the maintenance of whole-body glucose homeostasis and its dysregulation is a consistent feature in all forms of diabetes. However, knowledge of intracellular regulators that modulate b-cell function remains incomplete. We investigated the physiological role of ROCK1 in the regulation of insulin secretion and glucose homeostasis. Methods: Mice lacking ROCK1 in pancreatic β-cells (RIP-Cre; ROCK1loxP/loxP, β-ROCK1-/-) were studied. Glucose and insulin tolerance tests as well as glucose-stimulated insulin secretion (GSIS) were measured. Insulin secretion response to a direct glucose or pyruvate or pyruvate kinase (PK) activator stimulation in isolated islets from β-ROCK1-/- mice or β-cell lines with knockdown of ROCK1 were also evaluated. Proximity ligation assay was performed to determine the physical interactions between PK and ROCK1. Results: Mice with a deficiency of ROCK1 in pancreatic β-cells exhibited significantly increased blood glucose levels and reduced serum insulin without changes in body weight. Interestingly, β-ROCK1-/- mice displayed progressive impairment of glucose tolerance while maintaining insulin sensitivity mostly due to impaired GSIS. Consistently, GSIS was markedly decreased in ROCK1-deficient islets and ROCK1 knockdown INS-1 cells. Concurrently, ROCK1 blockade led to a significant decrease in intracellular calcium levels, ATP levels, and oxygen consumption rates in isolated islets and INS-1 cells. Treatment of ROCK1-deficient islets or ROCK1 knockdown β-cells either with pyruvate or a PK activator rescued the impaired GSIS. Mechanistically, we observed that ROCK1 binding to PK is greatly enhanced by glucose stimulation in β-cells. Conclusions: Our findings demonstrate that β-cell ROCK1 is essential for glucose-stimulated insulin secretion and maintenance of glucose homeostasis and that ROCK1 acts as an upstream regulator of glycolytic pyruvate kinase signaling.


2021 ◽  
Author(s):  
Ka-Cheuk Liu ◽  
Alethia Villasenor ◽  
Nicole Schmitner ◽  
Niki Radros ◽  
Linn Rautio ◽  
...  

AbstractTo investigate the role of the vasculature in pancreatic β-cell regeneration, we crossed a zebrafish β-cell ablation model into the avascular npas4l mutant (i.e. cloche). Surprisingly, β-cell regeneration increased markedly in npas4l mutants owing to the ectopic differentiation of β-cells in the mesenchyme, a phenotype not previously reported in any models. The ectopic β-cells expressed endocrine markers of pancreatic β-cells, and also reduced glucose levels in the β-cell ablation model. Through lineage tracing, we determined that the vast majority of these ectopic β-cells derived from the mesodermal lineage. Notably, ectopic β-cells were found in npas4l mutants as well as following knockdown of the endothelial determinant Etv2. Together, these data indicate that in the absence of endothelial specification, mesodermal cells possess a remarkable plasticity enabling them to form β-cells, which are normally endodermal in origin. Understanding the restriction of this differentiation plasticity will help exploit an alternative source for β-cell regeneration.


2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Bingyuan Yang ◽  
Brittney A. Covington ◽  
Wenbiao Chen

AbstractThe pathological feature of diabetes, hyperglycemia, is a result of an inadequate number and/or function of insulin producing β cells. Replenishing functional β cells is a strategy to cure the disease. Although β-cell regeneration occurs in animal models under certain conditions, human β cells are refractory to proliferation. A better understanding of both the positive and the negative regulatory mechanisms of β-cell regeneration in animal models is essential to develop novel strategies capable of inducing functional β cells in patients. Zebrafish are an attractive model system for studying β-cell regeneration due to the ease to which genetic and chemical-genetic approaches can be used as well as their high regenerative capacity. Here, we highlight the current state of β-cell regeneration studies in zebrafish with an emphasis on cell signaling mechanisms.


2020 ◽  
Vol 117 (49) ◽  
pp. 31219-31230
Author(s):  
Shanshan Tang ◽  
Mingfeng Zhang ◽  
Samuel Zeng ◽  
Yaxun Huang ◽  
Melissa Qin ◽  
...  

Type 1 diabetes (T1D) results from the autoimmune destruction of β cells, so cure of firmly established T1D requires both reversal of autoimmunity and restoration of β cells. It is known that β cell regeneration in nonautoimmune diabetic mice can come from differentiation of progenitors and/or transdifferentiation of α cells. However, the source of β cell regeneration in autoimmune nonobese diabetic (NOD) mice remains unclear. Here, we show that, after reversal of autoimmunity by induction of haploidentical mixed chimerism, administration of gastrin plus epidermal growth factor augments β cell regeneration and normalizes blood glucose in the firmly established diabetic NOD mice. Using transgenic NOD mice with inducible lineage-tracing markers for insulin-producing β cells, Sox9+ductal progenitors, Nestin+mesenchymal stem cells, and glucagon-producing α cells, we have found that both reactivation of dysfunctional low-level insulin expression (insulinlo) β cells and neogenesis contribute to the regeneration, with the latter predominantly coming from transdifferentiation of α cells. These results indicate that, after reversal of autoimmunity, reactivation of β cells and transdifferentiation of α cells can provide sufficient new functional β cells to reach euglycemia in firmly established T1D.


2019 ◽  
Vol 16 (3) ◽  
pp. 278-284 ◽  
Author(s):  
Anoja Priyadarshani Attanayake ◽  
Kamani Ayoma Perera Wijewardana Jayatilaka ◽  
Lakmini Kumari Boralugoda Mudduwa ◽  
Chitra Pathirana

Background:Effective β-cell regeneration is a recognized therapeutic strategy in the treatment of type 1 diabetes mellitus. Regeneration of β-cells could be achieved via exogenous natural sources as medicinal plant extracts. Medicinal plants selected for the investigation were Spondias pinnata (Linn. f.) Kurz, Coccinia grandis (L.) Voigt and Gmelina arborea Roxb. The objective was to determine the β-cell regenerative potential of these plant extracts in alloxan-induced diabetic rats. Alloxan monohydrate was used to induce diabetes (150 mg/kg, ip).Methods:Wistar albino rats were divided into six groups (n=6); healthy untreated rats (healthy control), alloxan-induced diabetic untreated rats (diabetic control), diabetic rats received the extracts (treatment groups) of S. pinnata (1.0 g/kg), C. grandis (0.75 g/kg), G. arobrea (1.00 g/kg) and diabetic rats received glibenclamide (0.5 mg/kg; positive control). The above treatment was continued for 30 days. On the 30th day, the rats were sacrificed and biochemical parameters were determined. In addition, histopathology and immunohistochemistry on the pancreatic tissue were done on the 30th day.Results:According to the results obtained for biochemical parameters, there was a significant increase in the concentrations of serum insulin and C-peptide in plant extracts treated diabetic rats (p < 0.05). The extract of C. grandis produced the highest degree of β-cell regeneration demonstrated through an increase in the number of islets and percentage of the insulin-secreting β-cells (75%) in the pancreas of diabetic rats (p < 0.05) based on the histopathology and immunohistochemistry findings.Conclusion:The results revealed that the selected extracts of C. grandis (0.75 g/kg), G. arborea (1.00 g/kg) and S. pinnata (1.00 g/kg) exerted β-cell regenerative potential in diabetic rats. The three plant extracts would be valued as natural agents of prompting the β-cell regeneration in vivo.


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