scholarly journals Polyamines and insulin production in isolated mouse pancreatic islets

1988 ◽  
Vol 252 (3) ◽  
pp. 701-707 ◽  
Author(s):  
N Welsh ◽  
A Sjöholm
Keyword(s):  
Insulin Release ◽  
High Glucose ◽  
Glucose Concentration ◽  
Culture Media ◽  
Protein Biosynthesis ◽  
Insulin Biosynthesis ◽  
Cell Physiology ◽  
High Glucose Concentration ◽  
Insulin Production

The aim of the present study was to evaluate the role of polyamines in the metabolism and insulin production of pancreatic-islet cells. For this purpose islets were prepared from adult mice and used either immediately or after tissue culture. There was a significant decrease in the islet content of spermidine during culture, although the effect was less pronounced in a high glucose concentration. Furthermore, a stimulatory effect of a high glucose concentration, as compared with low guclose, on the content of spermine was observed. To elucidate further the role of polyamaines in beta-cell physiology, the ornithine decarboxylase inhibitors difuoromethylornithine (DFMO) and methylacetylenic putrescine (MAP) and the S-adenosylmethionine decarboxylase inhibitor ethylglyoxal bis(guanylhydrazone) (EGBG) were added to the culture media. Addition of DFMO together with MAP decreased the cellular contents of putrescine and spermidine, whereas the content of sperimine was unaffected. When EGBG was added in combination with DFMO and MAP, there was a decrease in the content of spermine also. Cell viability in the islets depleted of their polyamine contents was not impaired, as assessed by determinations of oxygen-uptake rates and ATP contents. Depletion of putescine plus spermidine by addition of DFMO+MAP was associated with decreased biosynthesis of (pro)insulin and total protein. When the content of spermine was decreased also by the further addition of EGBG, the decrease in (pro) insulin biosynthesis was more pronounced and was paralleled by a decrease in the insulin-mRNA content. Under these conditions, the glucose-stimulated insulin release, the insulin content and the rates of islet DNA synthesis were also decreased. It is concluded that putrescine and spermidine are necessary for the maintenance of normal insulin and protein biosynthesis, whereas spermine may exert a role in some other cellular processes, such as DNA replication, RNA transcription and glucose-stimulated insulin release.

scholarly journals High Glucose Concentration Stimulates NHE-1 Activity in Distal Nephron Cells: the Role of the Mek/Erk1/2/p90RSKand p38MAPK Signaling Pathways

2014 ◽  
Vol 33 (2) ◽  
pp. 333-343 ◽  
Author(s):  
Juliana Martins da Costa-Pessoa ◽  
Rosélia Santos Damasceno ◽  
Ubiratan Fabres Machado ◽  
Olívia Beloto-Silva ◽  
Maria Oliveira-Souza
Keyword(s):  
Signaling Pathways ◽  
High Glucose ◽  
Glucose Concentration ◽  
High Glucose Concentration ◽  
Distal Nephron ◽  
P38mapk Signaling

High glucose concentration suppresses mesangial laminin B2 gene expression

1991 ◽  
Vol 5 (2-3) ◽  
pp. 118-120 ◽  
Author(s):  
Shigehiro Katayama ◽  
Mari Abe ◽  
Kiyoshi Tanaka ◽  
Akira Omoto ◽  
Kiyohiko Negishi ◽  
...  
Keyword(s):  
Gene Expression ◽  
High Glucose ◽  
Glucose Concentration ◽  
High Glucose Concentration

scholarly journals Sulodexide reduces glucose induced senescence in human retinal endothelial cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Gericke ◽  
K. Suminska-Jasińska ◽  
A. Bręborowicz
Keyword(s):  
Endothelial Cells ◽  
High Glucose ◽  
Glucose Concentration ◽  
Chronic Exposure ◽  
Replicative Senescence ◽  
Population Doubling ◽  
Population Doubling Time ◽  
High Glucose Concentration ◽  
Retinal Endothelial Cells

AbstractChronic exposure of retinal endothelium cells to hyperglycemia is the leading cause of diabetic retinopathy. We evaluated the effect of high glucose concentration on senescence in human retinal endothelial cells (HREC) and modulation of that effect by Sulodexide. Experiments were performed on HREC undergoing in vitro replicative senescence in standard medium or medium supplemented with glucose 20 mmol/L (GLU) or mannitol 20 mnol/L (MAN). Effect of Sulodexide 0.5 LRU/mL (SUL) on the process of HREC senescence was studied. Glucose 20 mmol/L accelerates senescence of HREC: population doubling time (+ 58%, p < 0.001) β-galactosidase activity (+ 60%, p < 0.002) intracellular oxidative stress (+ 65%, p < 0.01), expression of p53 gene (+ 118%, p < 0.001). Senescent HREC had also reduced transendothelial electrical resistance (TEER) (− 30%, p < 0.001). Mannitol 20 mmol/L used in the same scenario as glucose did not induce HREC senescence. In HREC exposed to GLU and SUL, the senescent changes were smaller. HREC, which became senescent in the presence of GLU, demonstrated higher expression of genes regulating the synthesis of Il6 and VEGF-A, which was reflected by increased secretion of these cytokines (IL6 + 125%, p < 0.001 vs control and VEGF-A + 124% p < 0.001 vs control). These effects were smaller in the presence of SUL, and additionally, an increase of TEER in the senescent HREC was observed. Chronic exposure of HREC to high glucose concentration in medium accelerates their senescence, and that process is reduced when the cells are simultaneously exposed to Sulodexide. Additionally, Sulodexide decreases the secretion of IL6 and VEGF-A from senescent HREC and increases their TEER.

scholarly journals The influence of high glucose concentration on the ability of mesenchymal stromal cells to stimulate blood vessel growth

2011 ◽  
Vol 14 (2) ◽  
pp. 32-35 ◽  
Author(s):  
Zhanna Alekseevna Akopyan ◽  
Georgy Vladimirovich Sharonov ◽  
Tatiana Nikolaevna Kochegura ◽  
Natalya Fedorovna Il'yashenko ◽  
Igor Eduardovich Belyanko ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Blood Vessel ◽  
High Glucose ◽  
Glucose Concentration ◽  
Functional Activity ◽  
Human Adipose Tissue ◽  
Diabetic Patients ◽  
High Glucose Concentration ◽  
Vessel Growth ◽  
Negative Effect

Adipose issue is a source of mesenchymal stem cells (MSC) that can be used to stimulate blood vessel growth in ischemic tissues. Various metabolicdisorders including hypeglycemia may have negative effect on therapeutic properties of these cells. Aim. To study the influence of high glucose concentration on functional activity in human adipose tissue. Materials and methods. Flow cytometry and real time PCR were used to study functional activity of cultured MSC from human adipose issue at highglucose concentration. Results. Prolonged (10-12 days) incubation at a high glucose concentration (25 mM) suppressed the ability of MSC to stimulate angiogenesis. Also,glucose modified expression of genes activating and inhibiting angiogenesis but had no effect on MSC proliferation and apoptosis. Conclusion. High glucose concentration suppresses angiogenic activity of MSC in adipose tissue; it may account for incomplete restoration of bloodflow in diabetic patients.

scholarly journals Long-term effects of glucose on insulin release and glucose oxidation by mouse pancreatic islets maintained in tissue culture

1974 ◽  
Vol 140 (3) ◽  
pp. 377-382 ◽  
Author(s):  
Arne Andersson
Keyword(s):  
Tissue Culture ◽  
B Cells ◽  
Pancreatic Islets ◽  
Insulin Release ◽  
High Glucose ◽  
Glucose Concentration ◽  
Glucose Oxidation ◽  
Extracellular Glucose Concentration ◽  
Extracellular Glucose ◽  
Mouse Pancreatic Islets

Rates of glucose oxidation and insulin release in response to a wide range of glucose concentrations were studied in short-term experiments in isolated mouse pancreatic islets maintained in tissue culture for 6 days at either a physiological glucose concentration (6.7mm) or at a high glucose concentration (28mm). The curves relating glucose oxidation or insulin release to the extracellular glucose concentration obtained with islets cultured in 6.7mm-glucose displayed a sigmoid shape similar to that observed for freshly isolated non-cultured islets. By contrast islets that had been cultured in 28mm-glucose showed a linear relationship between the rate of glucose oxidation and the extracellular glucose concentration up to about 8mm-glucose. The maximal oxidative rate was twice that of the non-cultured islets and the glucose concentration associated with the half-maximal rate considerably decreased. In islets cultured at 28mm-glucose there was only a small increase in the insulin release in response to glucose, probably due to a depletion of stored insulin in those B cells that had been cultured in a high-glucose medium. It is concluded that exposure of B cells for 6 days to a glucose concentration comparable with that found in diabetic individuals causes adaptive metabolic alterations rather than degeneration of these cells.

scholarly journals High Glucose Concentration Promotes Vancomycin-Enhanced Biofilm Formation of Vancomycin-Non-Susceptible Staphylococcus aureus in Diabetic Mice

PLoS ONE ◽  
2015 ◽  
Vol 10 (8) ◽  
pp. e0134852 ◽  
Author(s):  
Chi-Yu Hsu ◽  
Jwu-Ching Shu ◽  
Mei-Hui Lin ◽  
Kowit-Yu Chong ◽  
Chien-Cheng Chen ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
High Glucose ◽  
Glucose Concentration ◽  
Biofilm Formation ◽  
High Glucose Concentration ◽  
Diabetic Mice
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