scholarly journals High Glucose Aggravates the Detrimental Effects of Pancreatic Stellate Cells on Beta-Cell Function

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Min Zha ◽  
Wei Xu ◽  
Qing Zhai ◽  
Fengfei Li ◽  
Bijun Chen ◽  
...  

Background and Aims. We here assess the effects of PSCs onβ-cell function and apoptosisin vivoandin vitro.Materials and Methods.PSCs were transplanted into Wistar and Goto-Kakizaki (GK) rats. Sixteen weeks after transplantation,β-cell function, apoptosis, and islet fibrosis were assessed.In vitrothe effects of PSCs conditioned medium (PSCs-CM) and/or high concentration of glucose on INS-1 cell function was assessed by measuring insulin secretion, INS-1 cell survival, apoptosis, and endoplasmic reticulum stress (ER stress) associated CHOP expression.Results. PSCs transplantation exacerbated the impairedβ-cell function in GK rats, but had no significant effects in Wistar rats.In vitro, PSCs-CM caused impaired INS-1 cell viability and insulin secretion and increased apoptosis, which were more pronounced in the presence of high glucose.Conclusion.Our study demonstrates that PSCs induceβ-cell failurein vitroandin vivo.

Endocrinology ◽  
2012 ◽  
Vol 153 (2) ◽  
pp. 621-630 ◽  
Author(s):  
Rie Saito ◽  
Satoko Yamada ◽  
Yoritsuna Yamamoto ◽  
Tsutomu Kodera ◽  
Akemi Hara ◽  
...  

Activin A is a differentiation factor for β-cells and is effective to promote β-cell neogenesis. Activin A is also an autocrine activator of pancreatic stellate cells, which play a critical role in fibrogenesis of the pancreas. Conophylline (CnP) is a natural compound, which reproduces the effect of activin on β-cell differentiation and promotes β-cell neogenesis when administered in vivo. However, its effect on stellate cells is not known. We therefore investigated the effect of CnP on stellate cells both in vitro and in vivo. Unlike activin A, CnP inhibited activation of cultured stellate cells and reduced the production of collagen. We then analyzed the involvement of stellate cells in islet fibrosis in Goto-Kakizaki (GK) rats, a model of type 2 diabetes mellitus. In pancreatic sections obtained from 6-wk-old GK rats, CD68-positive macrophages and glial fibrillary acidic protein- and α-smooth muscle actin-positive stellate cells infiltrated into islets. Later, the number of macrophages was increased, and the α-smooth muscle actin staining of stellate cells became stronger, indicating the involvement of stellate cells in islet fibrosis in GK rats. When CnP was administered orally for 4 wk, starting from 6 wk of age, invasion of stellate cells and macrophages was markedly reduced and islet fibrosis was significantly improved. The insulin content was twice as high in CnP-treated rats. These results indicate that CnP exerts antifibrotic actions both in vitro and in vivo and improves islet fibrosis in Goto-Kakizaki rats.


2019 ◽  
Vol 5 (9) ◽  
pp. eaax2770 ◽  
Author(s):  
Praneeth R. Kuninty ◽  
Ruchi Bansal ◽  
Susanna W. L. De Geus ◽  
Deby F. Mardhian ◽  
Jonas Schnittert ◽  
...  

Abundant desmoplastic stroma is the hallmark for pancreatic ductal adenocarcinoma (PDAC), which not only aggravates the tumor growth but also prevents tumor penetration of chemotherapy, leading to treatment failure. There is an unmet clinical need to develop therapeutic solutions to the tumor penetration problem. In this study, we investigated the therapeutic potential of integrin α5 (ITGA5) receptor in the PDAC stroma. ITGA5 was overexpressed in the tumor stroma from PDAC patient samples, and overexpression was inversely correlated with overall survival. In vitro, knockdown of ITGA5 inhibited differentiation of human pancreatic stellate cells (hPSCs) and reduced desmoplasia in vivo. Our novel peptidomimetic AV3 against ITGA5 inhibited hPSC activation and enhanced the antitumor effect of gemcitabine in a 3D heterospheroid model. In vivo, AV3 showed a strong reduction of desmoplasia, leading to decompression of blood vasculature, enhanced tumor perfusion, and thereby the efficacy of gemcitabine in co-injection and patient-derived xenograft tumor models.


2008 ◽  
Vol 294 (1) ◽  
pp. E168-E175 ◽  
Author(s):  
Jamileh Movassat ◽  
Danièle Bailbé ◽  
Cécile Lubrano-Berthelier ◽  
Françoise Picarel-Blanchot ◽  
Eric Bertin ◽  
...  

The adult Goto-Kakizaki (GK) rat is characterized by impaired glucose-induced insulin secretion in vivo and in vitro, decreased β-cell mass, decreased insulin sensitivity in the liver, and moderate insulin resistance in muscles and adipose tissue. GK rats do not exhibit basal hyperglycemia during the first 3 wk after birth and therefore could be considered prediabetic during this period. Our aim was to identify the initial pathophysiological changes occurring during the prediabetes period in this model of type 2 diabetes (T2DM). To address this, we investigated β-cell function, insulin sensitivity, and body composition in normoglycemic prediabetic GK rats. Our results revealed that the in vivo secretory response of GK β-cells to glucose is markedly reduced and the whole body insulin sensitivity is increased in the prediabetic GK rats in vivo. Moreover, the body composition of suckling GK rats is altered compared with age-matched Wistar rats, with an increase of the number of adipocytes before weaning despite a decreased body weight and lean mass in the GK rats. None of these changes appeared to be due to the postnatal nutritional environment of GK pups as demonstrated by cross-fostering GK pups with nondiabetic Wistar dams. In conclusion, in the GK model of T2DM, β-cell dysfunction associated with increased insulin sensitivity and the alteration of body composition are proximal events that might contribute to the establishment of overt diabetes in adult GK rats.


1986 ◽  
Vol 251 (1) ◽  
pp. E86-E91 ◽  
Author(s):  
M. T. Bihoreau ◽  
A. Ktorza ◽  
A. Kervran ◽  
L. Picon

The effects of gestational hyperglycemia on B-cell function were studied in near-term fetuses from unrestrained pregnant rats made slightly or highly hyperglycemic using continuous glucose infusion during the last week of pregnancy. Pancreatic and plasma insulin and insulin secretion in vitro were studied in the fetuses. Compared with controls, slightly hyperglycemic fetuses showed increased pancreatic and plasma insulin concentrations and similar insulin release in response to glucose in vitro. In highly hyperglycemic fetuses, pancreatic and plasma insulin concentrations were unchanged compared with controls, and insulin release in vitro was insensitive to glucose and to the mixture glucose plus theophylline. These results confirm that glucose is able to stimulate insulin secretion in normal or slightly hyperglycemic fetuses and suggest that severe hyperglycemia per se, without association of other metabolic disorders or toxic injuries, profoundly alters the stimulus-secretion coupling of the fetal rat B-cell.


2009 ◽  
Vol 390 (10) ◽  
Author(s):  
Claus Kordes ◽  
Iris Sawitza ◽  
Dieter Häussinger

Abstract Stellate cells are vitamin A-storing cells of liver and pancreas and have been described in all vertebrates ranging from lampreys (primitive fish) to humans, demonstrating their major importance. This cell type is thought to contribute to fibrosis, a condition characterized by an excess deposition of extracellular matrix proteins. Recently, the expression of stem/progenitor cell markers, such as CD133 (prominin-1) and Oct4, was discovered in hepatic stellate cells (HSCs) of rats. Moreover, HSCs possess signaling pathways important for maintenance of stemness and cell differentiation, such as hedgehog, β-catenin-dependent Wnt, and Notch signaling, and are resistant to CD95-mediated apoptosis. In analogy to a stem cell niche, some characteristics of quiescent HSC are maintained by aid of a special microenvironment located in the space of Dissé. Finally, stellate cells display a differentiation potential as investigated in vitro and in vivo. Collectively all these properties are congruently found in stem/progenitor cells and support the concept that stellate cells are undifferentiated cells, which might play an important role in liver regeneration. The present review highlights findings related to this novel aspect of stellate cell biology.


2020 ◽  
Author(s):  
Akansha Mishra ◽  
Siming Liu ◽  
Joseph Promes ◽  
Mikako Harata ◽  
William Sivitz ◽  
...  

Perilipin 2 (PLIN2) is the lipid droplet (LD) protein in β cells that increases under nutritional stress. Down-regulation of PLIN2 is often sufficient to reduce LD accumulation. To determine whether PLIN2 positively or negatively affects β cell function under nutritional stress, PLIN2 was down-regulated in mouse β cells, INS1 cells, and human islet cells. β cell specific deletion of PLIN2 in mice on a high fat diet reduced glucose-stimulated insulin secretion (GSIS) in vivo and in vitro. Down-regulation of PLIN2 in INS1 cells blunted GSIS after 24 h incubation with 0.2 mM palmitic acids. Down-regulation of PLIN2 in human pseudoislets cultured at 5.6 mM glucose impaired both phases of GSIS, indicating that PLIN2 is critical for GSIS. Down-regulation of PLIN2 decreased specific OXPHOS proteins in all three models and reduced oxygen consumption rates in INS1 cells and mouse islets. Moreover, we found that PLIN2 deficient INS1 cells increased the distribution of a fluorescent oleic acid analog to mitochondria and showed signs of mitochondrial stress as indicated by susceptibility to fragmentation and alterations of acyl-carnitines and glucose metabolites. Collectively, PLIN2 in β cells have an important role in preserving insulin secretion, β cell metabolism and mitochondrial function under nutritional stress.


2019 ◽  
Vol 128 (10) ◽  
pp. 644-653
Author(s):  
Felicia Gerst ◽  
Christine Singer ◽  
Katja Noack ◽  
Dunia Graf ◽  
Gabriele Kaiser ◽  
...  

AbstractGlucose-stimulated insulin secretion (GSIS) is the gold standard for β-cell function. Both experimental and clinical diabetology, i. e., preceding transplantation of isolated human islets, depend on functional testing. However, multiple factors influence GSIS rendering the comparison of different in vitro tests of glucose responsiveness difficult. This study examined the influence of bovine serum albumin (BSA)-coupled fatty acids on GSIS. Isolated islet preparations of human donors and of 12-months old mice displayed impaired GSIS in the presence of 0.5% FFA-free BSA compared to 0.5% BSA (fraction V, not deprived from fatty acids). In aged INS-1E cells, i. e. at a high passage number, GSIS became highly sensitive to FFA-free BSA. Readdition of 30 µM palmitate or 30 µM oleate to FFA-free BSA did not rescue GSIS, while the addition of 100 µM palmitate and the raise of extracellular Ca2+from 1.3 to 2.6 mM improved glucose responsiveness. A high concentration of palmitate (600 µM), which fully activates FFA1, largely restored insulin secretion. The FFA1-agonist TUG-469 also increased insulin secretion but to a lesser extent than palmitate. Glucose- and TUG-induced Ca2+oscillations were impaired in glucose-unresponsive, i. e., aged INS-1E cells. These results suggest that fatty acid deprivation (FFA-free BSA) impairs GSIS mainly through an effect on Ca2+sensitivity.


2015 ◽  
Vol 35 (5) ◽  
pp. 1892-1904 ◽  
Author(s):  
Dan-dan Yin ◽  
Er-bao Zhang ◽  
Liang-hui You ◽  
Ning Wang ◽  
Lin-tao Wang ◽  
...  

Background: Increasing evidence indicates that long noncoding RNAs (IncRNAs) perform specific biological functions in diverse processes. Recent studies have reported that IncRNAs may be involved in β cell function. The aim of this study was to characterize the role of IncRNA TUG1 in mouse pancreatic β cell functioning both in vitro and in vivo. Methods: qRT-PCR analyses were performed to detect the expression of lncRNA TUG1 in different tissues. RNAi, MTT, TUNEL and Annexin V-FITC assays and western blot, GSIS, ELISA and immunochemistry analyses were performed to detect the effect of lncRNA TUG1 on cell apoptosis and insulin secretion in vitro and in vivo. Results: lncRNA TUG1 was highly expressed in pancreatic tissue compared with other organ tissues, and expression was dynamically regulated by glucose in Nit-1 cells. Knockdown of lncRNA TUG1 expression resulted in an increased apoptosis ratio and decreased insulin secretion in β cells both in vitro and in vivo . Immunochemistry analyses suggested decreased relative islet area after treatment with lncRNA TUG1 siRNA. Conclusion: Downregulation of lncRNA TUG1 expression affected apoptosis and insulin secretion in pancreatic β cells in vitro and in vivo. lncRNA TUG1 may represent a factor that regulates the function of pancreatic β cells.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
John K Bielicki ◽  
Anouar Hafiane ◽  
Jacques Genest ◽  
Jan O Johansson ◽  
Stefanie Bittner ◽  
...  

Background: Type 2 Diabetes Mellitus (T2DM) is associated with high cardiovascular disease (CVD) risk. Addressing the underlying atherogenesis and diabetes causing CVD in T2DM is important. CS6253 is an ABCA1 agonist peptide derived from the C-terminal of apoE that has shown macrophage specific reverse cholesterol transport, anti-atherosclerosis and anti-diabetic properties. Further studies were carried out to characterize metabolic effects. Methods: CS6253 was incubated with a) INS-1 823/13 cells to assess effects on insulin secretion and b) with L6-Glut4myc rat myoblasts to assess glucose uptake properties. Diet Induced Obesity (DIO) mice, i.e. C57BL/6 mice that had been fed 60% high-fat diet for 6 weeks, were treated with CS6253 and Glucose Tolerance Tests (GTT) performed after overnights fasting administering glucose 1g/kg ip. Results: CS6253 1mg/mL incubated for 2 hours under standard conditions with 3mM glucose showed a 3-fold increase in insulin secretion compared to control, i.e. 232(32) vs. 79(7) ng/M cells, p<0.001. 3 H-glucose uptake by CS6253 peptide in L6-Glut4myc rat myoblasts increased insulin’s glucose uptake capacity from 3800 to 4619 DPM/well, p<0.001 . CS6253 alone had no effect on 3 H-glucose uptake compared to control. DIO mice were treated with CS6253 30mg/kg sc alternate days or PBS control for 16 weeks. GTTs were performed after 2, 6 and 15 weeks treatment showing 39%, 45% and 57% reductions in the glucose-AUC compared to control, respectively, p<0.01 for all time points. Insulin response to GTT after 5 weeks treatment showed a strong improvement of the insulin-curve by CS6253, p<0.05 vs. placebo. CS6253 treated DIO mice showed a non-significant body weight decrease and a 17% reduction in liver weight, 5.28g vs. 4.36g, p<0.01. Discussion: CS6253 shows potent, sustained and increased anti-diabetic actions over the 16 weeks treatment period in DIO mice. In vivo and in vitro studies show improved pancreas β-cell function with increased glucose-mediated insulin secretion and also insulin sensitizing properties. CS6253’s combined anti-diabetic and anti-atherosclerosis properties suggest utility in the treatment of CVD and T2DM.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Hannah M. Komar ◽  
Gregory Serpa ◽  
Claire Kerscher ◽  
Erin Schwoegl ◽  
Thomas A. Mace ◽  
...  

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