Browsing by Author "Dimitrijević-Srećković, Vesna (6506375884)"

Introduction/Objective There are controversial data in the literature on the topic of effects of alcohol on insulin secretion, apoptosis, and necrosis of the endocrine and exocrine pancreas. The goal of this research was to determine how alcohol affects the insulin secretion and viability of human adult pancreatic islets in vitro during a seven-day incubation. Methods Human pancreatic tissue was digested with Collagenase XI, using a non-automated method. Cultures were incubated in Roswell Park Memorial Institute (RPMI) medium containing alcohol (10 μl of alcohol in 100 ml of medium). Insulin stimulation index (SI) and viability of the islets were determined on the first, third, and seventh day of cultivation. Results Analysis of the viability of the islets showed that there wasn’t significant difference between the control and the test group. In the test group, viability of the cultures declined with the time of incubation. SI of the test group was higher compared to the control group, by 50% and 25% on the first and third day of cultivation, respectively. On the seventh day, insulin secretion was reduced by 25%. The difference was not statistically significant (p > 0.05). In the test group, significant decline in insulin secretion was found on the third and seventh day of incubation (p ≤ 0.05). Conclusion Alcohol can increase or decrease insulin secretion of islets cultures, which may result in an inadequate response of pancreatic β-cells to blood glucose, leading to insulin resistance, and increased risk of developing type 2 diabetes. © 2017, Serbia Medical Society. All rights reserved.

Background/Aim. The most effective method for human adult pancreatic islets purification is density-gradient centrifugation. The aim of this study was to analyze the effects of non-automated purification on preservation of functional capacity of human adult pancreatic islet cells. Methods. Human pancreata were obtained after pancreatectomy in the patients with chronic pancreatitis or benign tumors. Pancreatic islets were purified by non-automated method in discontinuous Ficoll density gradient. The samples were divided in 2 fractions: purified (P) and non-purified (NP) cultures. Islets were stained with diphenyl-thiocarbazone. The efficiency of separation was determined by comparing percentage of stained cells in P and NP cultures on day 1, 3 and 7 of shortterm cultivation. Glucose-stimulated insulin secretion was expressed as stimulation index (SI). Results. The results obtained showed a statistically significant difference (p < 0.01) between P and NP cultures. P cultures had higher percentages of stained cells (70.43 ± 3.97%, 73.77 ± 4.22% and 71.34 ± 4.69% on the first, third and seventh day of cultivation, respectively) than NP cultures (53.68 ± 1.71%, 57.14 ± 3.94% and 43.97 ± 4.56%, respectively). P cultures had higher values of SI for the first, third and seventh day of cultivation than NP cultures (0.45 ± 0.08, 0.80 ± 0.21, 1.28 ± 0.15 and 0.46 ± 0.10, 0.752 ± .0.16, 0.76 ± 0.11 for P and NP cultures respectively). The difference was statistically significant on day seven (p = 0.01). Conclusion. Although during purification process islets were exposed to a number of insults that might result in cellular damage and functional impairment, our assessments showed that islets in P cultures preserved their functional capacity better than islets in NP cultures, since they had greater insulin secretion.