scholarly journals Simulated Cholinergic Reinnervation ofβ(INS-1) Cells: Antidiabetic Utility of Heterotypic Pseudoislets ContainingβCell and Cholinergic Cell

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Ao Jiao ◽  
Feng Li ◽  
Chengshuo Zhang ◽  
Wu Lv ◽  
Baomin Chen ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Pancreatic Islets ◽  
3D Culture ◽  
Cholinergic Neurons ◽  
Fold Increase ◽  
Culture Conditions ◽  
Glucose Stimulated Insulin Secretion ◽  
E Cadherin

Cholinergic neurons can functionally support pancreatic islets in controlling blood sugar levels. However, in islet transplantation, the level of cholinergic reinnervation is significantly lower compared to orthotopic pancreatic islets. This abnormal reinnervation affects the survival and function of islet grafts. In this study, the cholinergic reinnervation of beta cells was simulated by 2D and 3D coculture of INS-1 and NG108-15 cells. In 2D culture conditions, 20 mM glucose induced a 1.24-fold increase (p<0.0001) in insulin secretion from the coculture group, while in the 3D culture condition, a 1.78-fold increase (p<0.0001) in insulin secretion from heterotypic pseudoislet group was observed. Glucose-stimulated insulin secretion (GSIS) from 2D INS-1 cells showed minimal changes when compared to 3D structures. E-cadherin expressed in INS-1 and NG108-15 cells was the key adhesion molecule for the formation of heterotypic pseudoislets. NG108-15 cells hardly affected the proliferation of INS-1 cells in vitro. Heterotypic pseudoislet transplantation recipient mice reverted to normoglycemic levels faster and had a greater blood glucose clearance compared to INS-1 pseudoislet recipient mice. In conclusion, cholinergic cells can promote insulin-secreting cells to function better in vitro and in vivo and E-cadherin plays an important role in the formation of heterotypic pseudoislets.

scholarly journals In vivo and in vitro suppression by leptin of glucose-stimulated insulin hypersecretion in high glucose-fed rats

2000 ◽  
pp. 431-437 ◽  
Author(s):  
G Widdup ◽  
JM Bryson ◽  
D Pawlak ◽  
JL Phuyal ◽  
GS Denyer ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Basal Insulin ◽  
Insulin Response ◽  
Fold Increase ◽  
Tolerance Test ◽  
Glycaemic Index ◽  
Basal Insulin Secretion ◽  
Glucose Stimulated Insulin Secretion

OBJECTIVES: Chronic feeding to rats of high glycaemic index (GI) diets results in the hypersecretion of insulin in response to an i.v. glucose load. The first aim of this study was to see if this exaggerated insulin response was accompanied by a hypersensitivity to glucose stimulation in isolated islets in vitro. The second aim was to see if the adipocyte factor, leptin, was able to alter insulin secretion in this model both in vivo and in vitro. DESIGN AND METHODS: Rats were fed for 6 weeks either a high GI diet in which the carbohydrate component was mostly glucose (GLUC diet) or a low GI diet containing mostly amylose (AMOSE diet). Rats then underwent an i.v. glucose tolerance test (ivGTT) (1g/kg) with and without a prior infusion of leptin (133 microg/kg perh). Islets were then isolated from these rats and basal and glucose-stimulated insulin secretion (GSIS) measured in both the absence and presence (100ng/ml) of leptin. RESULTS AND CONCLUSIONS: Peak insulin response during the ivGTT was 3-fold greater in GLUC rats (P<0.001). Leptin had no effect on AMOSE rat insulin response but lowered the GLUC rat response to AMOSE rat levels. In vitro, basal insulin secretion was 4-fold greater in GLUC rats (P<0.05). At 20mmol/l glucose, there was no further increase in insulin secretion in GLUC rats but a 2-fold increase in AMOSE rats. Leptin had no effect on basal insulin secretion or GSIS in AMOSE rats but reduced basal insulin secretion and GSIS in GLUC rats. These results show insulin hypersecretion in high GI-fed rats may be reduced by leptin.

scholarly journals Regulation of glucokinase in pancreatic islets by prolactin: a mechanism for increasing glucose-stimulated insulin secretion during pregnancy

2007 ◽  
Vol 193 (3) ◽  
pp. 367-381 ◽  
Author(s):  
Anthony J Weinhaus ◽  
Laurence E Stout ◽  
Nicholas V Bhagroo ◽  
T Clark Brelje ◽  
Robert L Sorenson
Keyword(s):  
Insulin Secretion ◽  
Glucose Metabolism ◽  
Pancreatic Islets ◽  
Glucose Transporter ◽  
Β Cells ◽  
Glucose Transporter 2 ◽  
Underlying Mechanisms ◽  
Glucose Stimulated Insulin Secretion ◽  
Induced Changes

Glucokinase activity is increased in pancreatic islets during pregnancy and in vitro by prolactin (PRL). The underlying mechanisms that lead to increased glucokinase have not been resolved. Since glucose itself regulates glucokinase activity in β-cells, it was unclear whether the lactogen effects are direct or occur through changes in glucose metabolism. To clarify the roles of glucose metabolism in this process, we examined the interactions between glucose and PRL on glucose metabolism, insulin secretion, and glucokinase expression in insulin 1 (INS-1) cells and rat islets. Although the PRL-induced changes were more pronounced after culture at higher glucose concentrations, an increase in glucose metabolism, insulin secretion, and glucokinase expression occurred even in the absence of glucose. The presence of comparable levels of insulin secretion at similar rates of glucose metabolism from both control and PRL-treated INS-1 cells suggests the PRL-induced increase in glucose metabolism is responsible for the increase in insulin secretion. Similarly, increases in other known PRL responsive genes (e.g. the PRL receptor, glucose transporter-2, and insulin) were also detected after culture without glucose. We show that the upstream glucokinase promoter contains multiple STAT5 binding sequences with increased binding in response to PRL. Corresponding increases in glucokinase mRNA and protein synthesis were also detected. This suggests the PRL-induced increase in glucokinase mRNA and its translation are sufficient to account for the elevated glucokinase activity in β-cells with lactogens. Importantly, the increase in islet glucokinase observed with PRL is in line with that observed in islets during pregnancy.

scholarly journals Albumin Enhances Caspofungin Activity against Aspergillus Species by Facilitating Drug Delivery to Germinating Hyphae

2015 ◽  
Vol 60 (3) ◽  
pp. 1226-1233 ◽  
Author(s):  
Petros Ioannou ◽  
Aggeliki Andrianaki ◽  
Tonia Akoumianaki ◽  
Irene Kyrmizi ◽  
Nathaniel Albert ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Cell Culture ◽  
Antifungal Agents ◽  
Fold Increase ◽  
Culture Conditions ◽  
The Other ◽  
Related Factors ◽  
Content Type

The modestin vitroactivity of echinocandins againstAspergillusimplies that host-related factors augment the action of these antifungal agentsin vivo. We found that, in contrast to the other antifungal agents (voriconazole, amphotericin B) tested, caspofungin exhibited a profound increase in activity against variousAspergillusspecies under conditions of cell culture growth, as evidenced by a ≥4-fold decrease in minimum effective concentrations (MECs) (P= 0. 0005). Importantly, the enhanced activity of caspofungin againstAspergillusspp. under cell culture conditions was strictly dependent on serum albumin and was not observed with the other two echinocandins, micafungin and anidulafungin. Of interest, fluorescently labeled albumin bound preferentially on the surface of germinatingAspergillushyphae, and this interaction was further enhanced upon treatment with caspofungin. In addition, supplementation of cell culture medium with albumin resulted in a significant, 5-fold increase in association of fluorescently labeled caspofungin withAspergillushyphae (P< 0.0001). Collectively, we found a novel synergistic interaction between albumin and caspofungin, with albumin acting as a potential carrier molecule to facilitate antifungal drug delivery toAspergillushyphae.

scholarly journals A macrophage and theca cell-enriched stromal cell population influences growth and survival of immature murine follicles in vitro

Reproduction ◽  
2011 ◽  
Vol 141 (6) ◽  
pp. 809-820 ◽  
Author(s):  
Candace M Tingen ◽  
Sarah E Kiesewetter ◽  
Jennifer Jozefik ◽  
Cristina Thomas ◽  
David Tagler ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Culture System ◽  
Stromal Cell ◽  
Ovarian Follicle ◽  
3D Culture ◽  
Culture Conditions ◽  
Growth And Survival ◽  
3D Culture System

Innovations in in vitro ovarian follicle culture have revolutionized the field of fertility preservation, but the successful culturing of isolated primary and small secondary follicles remains difficult. Herein, we describe a revised 3D culture system that uses a feeder layer of ovarian stromal cells to support early follicle development. This culture system allows significantly improved primary and early secondary follicle growth and survival. The stromal cells, consisting mostly of thecal cells and ovarian macrophages, recapitulate the in vivo conditions of these small follicles and increase the production of androgens and cytokines missing from stromal cell-free culture conditions. These results demonstrate that small follicles have a stage-specific reliance on the ovarian environment, and that growth and survival can be improved in vitro through a milieu created by pre-pubertal ovarian stromal cell co-culture.

scholarly journals Deficiency of Proton-Sensing Ovarian Cancer G Protein-Coupled Receptor 1 Attenuates Glucose-Stimulated Insulin Secretion

Endocrinology ◽  
2012 ◽  
Vol 153 (9) ◽  
pp. 4171-4180 ◽  
Author(s):  
Takashi Nakakura ◽  
Chihiro Mogi ◽  
Masayuki Tobo ◽  
Hideaki Tomura ◽  
Koichi Sato ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Insulin Secretion ◽  
G Protein ◽  
Normal Glucose Tolerance ◽  
Extracellular Ph ◽  
G Protein Coupled Receptor ◽  
Glucose Stimulated Insulin Secretion ◽  
G Protein Coupled

Ovarian cancer G protein-coupled receptor 1 (OGR1) has been shown as a receptor for protons. In the present study, we aimed to know whether OGR1 plays a role in insulin secretion and, if so, the manner in which it does. To this end, we created OGR1-deficient mice and examined insulin secretion activity in vivo and in vitro. OGR1 deficiency reduced insulin secretion induced by glucose administered ip, although it was not associated with glucose intolerance in vivo. Increased insulin sensitivity and reduced plasma glucagon level may explain, in part, the unusual normal glucose tolerance. In vitro islet experiments revealed that glucose-stimulated insulin secretion was dependent on extracellular pH and sensitive to OGR1; insulin secretion at pH 7.4 to 7.0, but not 8.0, was significantly suppressed by OGR1 deficiency and inhibition of Gq/11 proteins. Insulin secretion induced by KCl and tolbutamide was also significantly inhibited, whereas that induced by several insulin secretagogues, including vasopressin, a glucagon-like peptide 1 receptor agonist, and forskolin, was not suppressed by OGR1 deficiency. The inhibition of insulin secretion was associated with the reduction of glucose-induced increase in intracellular Ca2+ concentration. In conclusion, the OGR1/Gq/11 protein pathway is activated by extracellular protons existing under the physiological extracellular pH of 7.4 and further stimulated by acidification, resulting in the enhancement of insulin secretion in response to high glucose concentrations and KCl.

Mice pancreatic islets protection from oxidative stress induced by single-walled carbon nanotubes through naringin

2018 ◽  
Vol 37 (12) ◽  
pp. 1268-1281 ◽  
Author(s):  
A Ahangarpour ◽  
S Alboghobeish ◽  
AA Oroojan ◽  
MA Dehghani
Keyword(s):  
Oxidative Stress ◽  
Carbon Nanotubes ◽  
Insulin Secretion ◽  
Pancreatic Islets ◽  
Mtt Assay ◽  
Antioxidant Defense System ◽  
Protective Effects ◽  
Cell Functions

The growing use of carbon nanotubes (CNTs) emphasizes the importance of its potential toxic effects on the human health. Previous studies proved that CNTs caused oxidative stress and decreased cell viability. On the other hand, reactive oxygen species (ROS) and oxidative stress impaired β-cell functions and reduced the insulin secretion. However, there is not any study on the effects of CNTs on islets and β-cells. Therefore, the present study aimed to evaluate the effects of single-walled CNTs (SWCNTs) on oxidative stress in islets in addition to the protective effects of naringin (NRG) as an antioxidant . We examined the effects of SWCNTs and naringin on islets by 3,4 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay; measurement of insulin secretion, ROS, and malondialdehyde (MDA); activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) peroxidase (GSH-Px); and content of GSH and mitochondrial membrane potential (MMP). The MTT assay demonstrated that decreased viability of islets cells was dose-dependent with exposure to SWCNTs. Further studies revealed that SWCNTs decreased insulin secretion and MMP, induced the formation of ROS, increased the level of MDA, and decreased the activities of SOD, GSH-Px, and CAT and content of GSH. Furthermore, the pretreatment of islets with naringin significantly reverted back these changes. These findings revealed that SWCNTs might induce the oxidative stress to pancreatic islets, causing the occurrence of diabetes, and the protective effects of naringin that was mediated by augmentation of the antioxidant defense system of islets. Our research indicated the necessity for further in vivo and in vitro researches on the effects of SWCNTs and naringin on diabetes.

In vitro lymphocyte recognition of islet cells following in vivo priming with allogeneic murine pancreatic islets

1984 ◽  
Vol 105 (1) ◽  
pp. 87-92 ◽  
Author(s):  
Joanne Scott ◽  
Peter G. MacKay ◽  
Åke Lernmark
Keyword(s):  
Lymph Node ◽  
Pancreatic Islets ◽  
Islet Cell ◽  
Islet Cells ◽  
Culture Conditions ◽  
Pancreatic Tissue ◽  
Insulin Dependent ◽  
Lymph Node Cells

Abstract. Lymphocytes from patients with insulin-dependent diabetes have been shown to be sensitized to pancreatic tissue antigens. Mice immunized with homologous pancreatic islets have been found to develop glucose intolerance and insulitis. Since lymphocytes may be involved in diabetogenesis, we wished to determine if lymph node cells from islet-immunized mice can recognize and respond to islet cells in vitro. A.TL female mice were immunized with an emulsion of BALB/c islet homogenate and complete Freund's adjuvant (CFA); sham-treated A.TL mice were injected with adjuvant and water. Mice were sacrificed 7–8 days later and the draining lymph nodes were removed. The lymph node cells were co-cultured with freshly prepared irradiated BALB/c islet cell, which served as stimulator cells. The co-cultures were incubated for 24–26 h at 37°C, followed by a 16 h [3H]thymidine (TdR) pulse. A significant proliferation of lymph node cells from islet-primed mice was induced during the in vitro stimulation with irradiated islet cells when compared with lymph node cells from sham-treated mice (P < 0.001). The response may be islet-cell-specific, since irradiated lymph node cells from BALB/c mice failed to proliferative response under the same culture conditions (P > 0.80).

scholarly journals 3D Hepatic Organoid-Based Advancements in LIVER Tissue Engineering

2021 ◽  
Vol 8 (11) ◽  
pp. 185
Author(s):  
Amit Panwar ◽  
Prativa Das ◽  
Lay Poh Tan
Keyword(s):  
Tissue Engineering ◽  
Self Assembly ◽  
Liver Tissue ◽  
3D Culture ◽  
Culture Method ◽  
Culture Conditions ◽  
Phenotypic Properties ◽  
Liver Tissue Engineering

Liver-associated diseases and tissue engineering approaches based on in vitro culture of functional Primary human hepatocytes (PHH) had been restricted by the rapid de-differentiation in 2D culture conditions which restricted their usability. It was proven that cells growing in 3D format can better mimic the in vivo microenvironment, and thus help in maintaining metabolic activity, phenotypic properties, and longevity of the in vitro cultures. Again, the culture method and type of cell population are also recognized as important parameters for functional maintenance of primary hepatocytes. Hepatic organoids formed by self-assembly of hepatic cells are microtissues, and were able to show long-term in vitro maintenance of hepato-specific characteristics. Thus, hepatic organoids were recognized as an effective tool for screening potential cures and modeling liver diseases effectively. The current review summarizes the importance of 3D hepatic organoid culture over other conventional 2D and 3D culture models and its applicability in Liver tissue engineering.

Abstract 14: The Anti-atherosclerosis ABCA1 Agonist CS6253 Confer Glucose Control by Improved Pancreas Beta-cell Insulin Secretion and Enhanced Peripheral Insulin Utility

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
John K Bielicki ◽  
Anouar Hafiane ◽  
Jacques Genest ◽  
Jan O Johansson ◽  
Stefanie Bittner ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Glucose Uptake ◽  
Cell Function ◽  
Insulin Response ◽  
Fold Increase ◽  
Liver Weight ◽  
Metabolic Effects ◽  
Cvd Risk

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.

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