Accelerated Functional Maturation of Isolated Neonatal Porcine Cell Clusters: In Vitro and In Vivo Results in NOD Mice

2005 ◽  
Vol 14 (5) ◽  
pp. 249-261 ◽  
Author(s):  
Giovanni Luca ◽  
Claudio Nastruzzi ◽  
Mario Calvitti ◽  
Ennio Becchetti ◽  
Tiziano Baroni ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Time Lag ◽  
Cell Mass ◽  
Nod Mice ◽  
Β Cell ◽  
Cell Clusters ◽  
Porcine Islets ◽  
Neonatal Porcine Islets

Neonatal porcine cell clusters (NPCCs) might replace human for transplant in patients with type 1 diabetes mellitus (T1DM). However, these islets are not immediately functional, due to their incomplete maturation/differentiation. We then have addressed: 1) to assess whether in vitro coculture of islets with homologous Sertoli cells (SC) would shorten NPCCs' functional time lag, by accelerating the β-cell biological maturation/differentiation; 2) to evaluate metabolic outcome of the SC preincubated, and microencapsulated NPCCs, upon graft into spontaneously diabetic NOD mice. The islets, isolated from <3 day piglets, were examined in terms of morphology/viability/function and final yield. SC effects on the islet maturation pathways, both in vitro and in vivo, upon microencapsulation in alginate/poly-L-ornithine, and intraperitoneal graft into spontaneously diabetic NOD mice were determined. Double fluorescence immunolabeling showed increase in β-cell mass for SC+ neonatal porcine islets versus islets alone. In vitro insulin release in response to glucose, as well as mRNA insulin expression, were significantly higher for SC+ neonatal porcine islets compared with control, thereby confirming SC-induced increase in viable and functional β-cell mass. Graft of microencapsulated SC+ neonatal porcine islets versus encapsulated islets alone resulted in significantly longer remission of hyperglycemia in NOD mice. We have preliminarily shown that the in vitro NPCCs' maturation time lag can dramatically be curtailed by coincubating these islets with SC. Graft of microencapsulated neonatal porcine islets, precultured in Sertoli cells, has been proven successful in correcting hyperglycemia in stringent animal model of spontaneous diabetes.

scholarly journals Effect of prolonged in vitro exposure to high glucose on neonatal porcine pancreatic islets

2006 ◽  
Vol 191 (1) ◽  
pp. 37-44 ◽  
Author(s):  
George Harb ◽  
Gregory S Korbutt
Keyword(s):  
High Glucose ◽  
Prolonged Exposure ◽  
Islet Cells ◽  
Cell Mass ◽  
Β Cells ◽  
Β Cell ◽  
Porcine Islets ◽  
Clinical Islet Transplantation ◽  
Neonatal Porcine Islets

Prolonged exposure to high glucose can influence the function, growth, and survival of pancreatic β-cells. In this study, we examine the effects of prolonged in vitro exposure to high glucose on neonatal porcine β-cells, a potentially useful source of insulin-producing cells for clinical islet transplantation. Neonatal porcine islets were prepared by culturing collagenase-digested pancreases for 1 week in 5.6 mM glucose, followed by an additional week in either 5.6, 10.0, or 28.0 mM glucose. An additional 2 days of culture in 5.6 mM glucose followed for recovery from high glucose. The 7-day culture period in 28.0 mM glucose failed to irreversibly impair glucose responsiveness and also caused a modest increase in β-cell mass. Immunostaining revealed that precursor cell differentiation was responsible for the increase in β-cell mass rather than β-cell proliferation. Islet cell survival was also assessed by a DNA fragmentation assay (TUNEL stain) to determine β-cell susceptibility to apoptosis after exposure to high glucose. Interestingly, although the total number of apoptotic islet cells did not drastically change after a week of culture in either 5.6, 10.0, or 28.0 mM glucose (25% TUNEL-positive), neither did the percentage of apoptotic β-cells. These encouraging results further support the use of neonatal porcine islets for clinical transplantation because of their ability to resist the cytotoxic effects of high glucose on islet function and survival.

scholarly journals AWRK6, a Novel GLP-1 Receptor Agonist, Attenuates Diabetes by Stimulating Insulin Secretion

2018 ◽  
Vol 19 (10) ◽  
pp. 3053
Author(s):  
Qiuyu Wang ◽  
Chunlin Zhao ◽  
Lili Jin ◽  
Hanyu Zhang ◽  
Qifan Miao ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Cell Mass ◽  
Membrane Integrity ◽  
The Body ◽  
Oral Glucose ◽  
Diabetic Mice ◽  
Β Cell ◽  
Min6 Cells

Diabetes is a metabolic disorder leading to many complications. The treatment of diabetes mainly depends on hypoglycemic drugs, often with side effects, which drive us to develop novel agents. AWRK6 was a peptide developed from the antimicrobial peptide Dybowskin-2CDYa in our previous study, and the availability of AWRK6 on diabetes intervention was unknown. Here, in vivo and in vitro experiments were carried out to investigate the effects of AWRK6 against diabetes. In diabetic mice, induced by high-fat diet followed by streptozocin (STZ) administration, the daily administration of AWRK6 presented acute and sustained hypoglycemic effects. The plasma insulin was significantly elevated by AWRK6 during an oral glucose tolerance test (OGTT). The relative β cell mass in diabetic mice was increased by AWRK6 treatment. The body weight and food intake were remarkably reduced by AWRK6 administration. In the mouse pancreatic β cell line Min6 cells, the intracellular calcium concentration was found to be enhanced under the treatment with AWRK6, and protein kinase A (PKA) inhibitor H-89 and Epac2 inhibitor HJC0350 represented inhibitory effects of the insulinotropic function of AWRK6. By FITC-AWRK6 incubation and GLP-1 receptor (GLP-1R) knockdown, AWRK6 proved to be a novel GLP-1R agonist. In addition, AWRK6 showed no toxicity in cell viability and membrane integrity in Min6 cells, and no hypoglycemia risk and no lethal toxicity in mice. In summary, AWRK6 was found as a novel agonist of GLP-1R, which could stimulate insulin secretion to regulate blood glucose and energy metabolism, via cAMP-calcium signaling pathway, without significant toxicity. The peptide AWRK6 might become a novel candidate for diabetes treatment.

Pancreatic islet-specific overexpression of Reg3β protein induced the expression of pro-islet genes and protected the mice against streptozotocin-induced diabetes mellitus

2011 ◽  
Vol 300 (4) ◽  
pp. E669-E680 ◽  
Author(s):  
Xiaoquan Xiong ◽  
Xiao Wang ◽  
Bing Li ◽  
Subrata Chowdhury ◽  
Yarong Lu ◽  
...  
Keyword(s):  
Cell Mass ◽  
Wild Type ◽  
Β Cell ◽  
Western Blots ◽  
Streptozotocin Induced Diabetes ◽  
In Vitro Insulin Secretion ◽  
Precise Role ◽  
Pancreatitis Associated Protein

Reg family proteins have been implicated in islet β-cell proliferation, survival, and regeneration. The expression of Reg3β (pancreatitis-associated protein) is highly induced in experimental diabetes and acute pancreatitis, but its precise role has not been established. Through knockout studies, this protein was shown to be mitogenic, antiapoptotic, and anti-inflammatory in the liver and pancreatic acinars. To test whether it can promote islet cell growth or survival against experimental damage, we developed β-cell-specific overexpression using rat insulin I promoter, evaluated the changes in normal islet function, gene expression profile, and the response to streptozotocin-induced diabetes. Significant and specific overexpression of Reg3β was achieved in the pancreatic islets of RIP-I/Reg3β mice, which exhibited normal islet histology, β-cell mass, and in vivo and in vitro insulin secretion in response to high glucose yet were slightly hyperglycemic and low in islet GLUT2 level. Upon streptozotocin treatment, in contrast to wild-type littermates that became hyperglycemic in 3 days and lost 15% of their weight, RIP-I/Reg3β mice were significantly protected from hyperglycemia and weight loss. To identify specific targets affected by Reg3β overexpression, a whole genome DNA microarray on islet RNA isolated from the transgenic mice revealed more than 45 genes significantly either up- or downregulated. Among them, islet-protective osteopontin/SPP1 and acute responsive nuclear protein p8/NUPR1 were significantly induced, a result further confirmed by real-time PCR, Western blots, and immunohistochemistry. Our results suggest that Reg3β is unlikely an islet growth factor but a putative protector that prevents streptozotocin-induced damage by inducing the expression of specific genes.

GLP-1(28–36) improves β-cell mass and glucose disposal in streptozotocin-induced diabetic mice and activates cAMP/PKA/β-catenin signaling in β-cells in vitro

2013 ◽  
Vol 304 (12) ◽  
pp. E1263-E1272 ◽  
Author(s):  
Weijuan Shao ◽  
Zhaoxia Wang ◽  
Wilfred Ip ◽  
Yu-Ting Chiang ◽  
Xiaoquan Xiong ◽  
...  
Keyword(s):  
Cyclin D1 ◽  
Cell Line ◽  
Cell Mass ◽  
Glucose Disposal ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
In Vitro Investigation

Recent studies have demonstrated that the COOH-terminal fragment of the incretin hormone glucagon-like peptide-1 (GLP-1), a nonapeptide GLP-1(28–36)amide, attenuates diabetes and hepatic steatosis in diet-induced obese mice. However, the effect of this nonapeptide in pancreatic β-cells remains largely unknown. Here, we show that in a streptozotocin-induced mouse diabetes model, GLP-1(28–36)amide improved glucose disposal and increased pancreatic β-cell mass and β-cell proliferation. An in vitro investigation revealed that GLP-1(28–36)amide stimulates β-catenin (β-cat) Ser675 phosphorylation in both the clonal INS-1 cell line and rat primary pancreatic islet cells. In INS-1 cells, the stimulation was accompanied by increased nuclear β-cat content. GLP-1(28–36)amide was also shown to increase cellular cAMP levels, PKA enzymatic activity, and cAMP response element-binding protein (CREB) and cyclic AMP-dependent transcription factor-1 (ATF-1) phosphorylation. Furthermore, GLP-1(28–36)amide treatment enhanced islet insulin secretion and increased the growth of INS-1 cells, which was associated with increased cyclin D1 expression. Finally, PKA inhibition attenuated the effect of GLP-1(28–36)amide on β-cat Ser675 phosphorylation and cyclin D1 expression in the INS-1 cell line. We have thus revealed the beneficial effect of GLP-1(28–36)amide in pancreatic β-cells in vitro and in vivo. Our observations suggest that GLP-1(28–36)amide may exert its effect through the PKA/β-catenin signaling pathway.

scholarly journals Human Islet Microtissues as an In Vitro and an In Vivo Model System for Diabetes

2021 ◽  
Vol 22 (4) ◽  
pp. 1813
Author(s):  
Joan Mir-Coll ◽  
Tilo Moede ◽  
Meike Paschen ◽  
Aparna Neelakandhan ◽  
Ismael Valladolid-Acebes ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Cell Function ◽  
Cell Mass ◽  
Human Islet ◽  
Critical Event ◽  
In Vivo Model ◽  
Β Cell

Loss of pancreatic β-cell function is a critical event in the pathophysiology of type 2 diabetes. However, studies of its underlying mechanisms as well as the discovery of novel targets and therapies have been hindered due to limitations in available experimental models. In this study we exploited the stable viability and function of standardized human islet microtissues to develop a disease-relevant, scalable, and reproducible model of β-cell dysfunction by exposing them to long-term glucotoxicity and glucolipotoxicity. Moreover, by establishing a method for highly-efficient and homogeneous viral transduction, we were able to monitor the loss of functional β-cell mass in vivo by transplanting reporter human islet microtissues into the anterior chamber of the eye of immune-deficient mice exposed to a diabetogenic diet for 12 weeks. This newly developed in vitro model as well as the described in vivo methodology represent a new set of tools that will facilitate the study of β-cell failure in type 2 diabetes and would accelerate the discovery of novel therapeutic agents.

scholarly journals Regulation of islet function and gene expression by prolactin during pregnancy

2019 ◽  
Author(s):  
Vipul Shrivastava ◽  
Megan Lee ◽  
Marle Pretorius ◽  
Guneet Makkar ◽  
Carol Huang
Keyword(s):  
Gene Expression ◽  
Insulin Secretion ◽  
Serum Insulin ◽  
Prolactin Receptor ◽  
Cell Mass ◽  
Insulin Level ◽  
Β Cells ◽  
Β Cell

AbstractPancreatic islets adapt to insulin resistance of pregnancy by up regulating β-cell proliferation and increase insulin secretion. Previously, we found that prolactin receptor (Prlr) signaling is important for this process, as heterozygous prolactin receptor-null (Prlr+/−) mice are glucose intolerant, had a lower number of β cells and lower serum insulin levels than wild type mice during pregnancy. However, since Prlr expression is ubiquitous, to determine its β-cell specific effects, we generated a transgenic mouse with a floxed Prlr allele under the control of an inducible promoter, allowing conditional deletion of Prlr from β cells in adult mice. In this study, we found that β-cell-specific Prlr reduction resulted in elevated blood glucose during pregnancy. Similar to our previous finding in mouse with global Prlr reduction, β-cell-specific Prlr loss led to a lower β-cell mass and a lower in vivo insulin level during pregnancy. However, these islets do not have an intrinsic insulin secretion defect when tested in vitro. Interestingly, when we compared the islet gene expression profile, using islets isolated from mice with global versus β-cell-specific Prlr reduction, we found some important differences in genes that regulate apoptosis and insulin secretion. This suggests that Prlr has both cell-autonomous and non-cell-autonomous effect on β cells, beyond its regulation of pro-proliferative genes.

scholarly journals Neratinib protects pancreatic beta cells in diabetes

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Amin Ardestani ◽  
Sijia Li ◽  
Karthika Annamalai ◽  
Blaz Lupse ◽  
Shirin Geravandi ◽  
...  
Keyword(s):  
Pancreatic Beta Cells ◽  
Cell Function ◽  
Cell Mass ◽  
Human Islets ◽  
Β Cells ◽  
Β Cell

Abstract The loss of functional insulin-producing β-cells is a hallmark of diabetes. Mammalian sterile 20-like kinase 1 (MST1) is a key regulator of pancreatic β-cell death and dysfunction; its deficiency restores functional β-cells and normoglycemia. The identification of MST1 inhibitors represents a promising approach for a β-cell-protective diabetes therapy. Here, we identify neratinib, an FDA-approved drug targeting HER2/EGFR dual kinases, as a potent MST1 inhibitor, which improves β-cell survival under multiple diabetogenic conditions in human islets and INS-1E cells. In a pre-clinical study, neratinib attenuates hyperglycemia and improves β-cell function, survival and β-cell mass in type 1 (streptozotocin) and type 2 (obese Leprdb/db) diabetic mouse models. In summary, neratinib is a previously unrecognized inhibitor of MST1 and represents a potential β-cell-protective drug with proof-of-concept in vitro in human islets and in vivo in rodent models of both type 1 and type 2 diabetes.

scholarly journals Prolactin Receptor Is Required for Normal Glucose Homeostasis and Modulation of β-Cell Mass during Pregnancy

Endocrinology ◽  
2008 ◽  
Vol 150 (4) ◽  
pp. 1618-1626 ◽  
Author(s):  
Carol Huang ◽  
Frances Snider ◽  
James C. Cross
Keyword(s):  
Cell Proliferation ◽  
Glucose Tolerance ◽  
Glucose Homeostasis ◽  
Prolactin Receptor ◽  
Cell Mass ◽  
Β Cell ◽  
Related Factors ◽  
Maternal Glucose

Increased islet mass is an adaptive mechanism that occurs to combat insulin resistance during pregnancy. Prolactin (PRL) can enhance β-cell proliferation and insulin secretion in vitro, yet whether it is PRL or other pregnancy-related factors that mediate these adaptive changes during pregnancy is unknown. The objective of this study was to determine whether prolactin receptor (Prlr) is required for normal maternal glucose homeostasis during pregnancy. An ip glucose tolerance test was performed on timed-pregnant Prlr+/+ and heterozygous null Prlr+/− mice on d 0, 15, and 18 of pregnancy. Compared with Prlr+/+ mice, Prlr+/− mice had impaired glucose clearance, decreased glucose-stimulated insulin release, higher nonfasted blood glucose, and lower insulin levels during but not before pregnancy. There was no difference in their insulin tolerance. Prlr+/+ mice show a significant incremental increase in islet density and β-cell number and mass throughout pregnancy, which was attenuated in the Prlr+/− mice. Prlr+/+ mice also had a more robust β-cell proliferation rate during pregnancy, whereas there was no difference in apoptosis rate between the Prlr+/+ and Prlr+/− mice before, during, or after pregnancy. Interestingly, genotype of the mothers had a significant impact on the offspring’s phenotype, such that daughters derived from Prlr+/− mothers had a more severe phenotype than those derived from Prlr+/+ mothers. In conclusion, this is the first in vivo demonstration that the action of pregnancy hormones, acting through Prlr, is required for normal maternal glucose tolerance during pregnancy by increasing β-cell mass.

scholarly journals Anti-Diabetic Effects and Mechanisms of Dietary Polysaccharides

Molecules ◽  
2019 ◽  
Vol 24 (14) ◽  
pp. 2556 ◽  
Author(s):  
Ganesan ◽  
Xu
Keyword(s):  
Oxidative Stress ◽  
Diabetes Mellitus ◽  
Molecular Mechanisms ◽  
Mapk Pathway ◽  
Cell Mass ◽  
Inflammatory Factors ◽  
Low Grade ◽  
Β Cell

Diabetes mellitus is a multifactorial, heterogeneous metabolic disorder, causing various health complications and economic issues, which apparently impacts the human’s life. Currently, commercial diabetic drugs are clinically managed for diabetic treatment that has definite side effects. Dietary polysaccharides mainly derive from natural sources, including medicinal plants, grains, fruits, vegetables, edible mushroom, and medicinal foods, and possess anti-diabetic potential. Hence, this review summarizes the effects of dietary polysaccharides on diabetes and underlying molecular mechanisms related to inflammatory factors, oxidative stress, and diabetes in various animal models. The analysis of literature and appropriate data on anti-diabetic polysaccharide from electronic databases was conducted. In vivo and in vitro trials have revealed that treatment of these polysaccharides has hypoglycemic, hypolipidemic, antioxidant, and anti-inflammatory effects, which enhance pancreatic β-cell mass and alleviates β-cell dysfunction. It enhances insulin signaling pathways through insulin receptors and activates the PI3K/Akt pathway, and eventually modulates ERK/JNK/MAPK pathway. In conclusion, dietary polysaccharides can effectively ameliorate hyperglycemia, hyperlipidemia, low-grade inflammation, and oxidative stress in type 2 diabetes mellitus (T2DM), and, thus, consumption of polysaccharides can be a valuable choice for diabetic control.

scholarly journals Tectorigenin enhances PDX1 expression and protects pancreatic β-cells by activating ERK and reducing ER stress

2020 ◽  
Vol 295 (37) ◽  
pp. 12975-12992 ◽  
Author(s):  
Xinlei Yao ◽  
Kun Li ◽  
Chen Liang ◽  
Zilong Zhou ◽  
Jiao Wang ◽  
...  
Keyword(s):  
Er Stress ◽  
Cell Mass ◽  
Therapeutic Use ◽  
Protective Effects ◽  
Β Cells ◽  
Β Cell ◽  
And Function ◽  
Pdx1 Expression

Pancreas/duodenum homeobox protein 1 (PDX1) is an important transcription factor that regulates islet β-cell proliferation, differentiation, and function. Reduced expression of PDX1 is thought to contribute to β-cell loss and dysfunction in diabetes. Thus, promoting PDX1 expression can be an effective strategy to preserve β-cell mass and function. Previously, we established a PDX1 promoter-dependent luciferase system to screen agents that can promote PDX1 expression. Natural compound tectorigenin (TG) was identified as a promising candidate that could enhance the activity of the promoter for the PDX1 gene. In this study, we first demonstrated that TG could promote the expression of PDX1 in β-cells via activating extracellular signal-related kinase (ERK), as indicated by increased phosphorylation of ERK; this effect was observed under either normal or glucotoxic/lipotoxic conditions. We then found that TG could suppress induced apoptosis and improved the viability of β-cells under glucotoxicity and lipotoxicity by activation of ERK and reduction of reactive oxygen species and endoplasmic reticulum (ER) stress. These effects held true in vivo as well: prophylactic or therapeutic use of TG could obviously inhibit ER stress and decrease islet β-cell apoptosis in the pancreas of mice given a high-fat/high-sucrose diet (HFHSD), thus dramatically maintaining or restoring β-cell mass and islet size, respectively. Accordingly, both prophylactic and therapeutic use of TG improved HFHSD-impaired glucose metabolism in mice, as evidenced by ameliorating hyperglycemia and glucose intolerance. Taken together, TG, as an agent promoting PDX1 expression exhibits strong protective effects on islet β-cells both in vitro and in vivo.

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