Laser Capture Microdissection Coupled Capillary Immunoassay to Study the Expression of PCK-2 on Spatially-Resolved Islets of Rat Langerhans

The platform for precise proteomic profiling of targeted cell populations from heterogeneous tissue sections is developed. We demonstrate a seamless and systematic integration of LCM with an automated cap-IA for the handling of a very small-sized dissected tissues section from the kidney, liver and pancreatic Langerhans islet of rats. Our analysis reveals that the lowest LCM section area ≥ 0.125 mm2 with 10 µm thickness can be optimized for the detection of proteins through LCM-cap-IA integration. We detect signals ranging from a highly-abundant protein, β-actin, to a low-abundance protein, LC-3AB, using 0.125 mm2 LCM section from rat kidney, but, so far, a relatively large section is required for good quality of results. This integration is applicable for a highly-sensitive and accurate assessment of microdissected tissue sections to decipher hidden proteomic information of pure targeted cells. To validate this integration, PCK2 protein expression is studied within Langerhans islets of normal and diabetic rats. Our results show significant overexpression of PCK2 in Langerhans islets of rats with long-term diabetes.

Langerhans islets induce anti-tumor immunity at the expense of glycemic control and predict chemotherapy response in pancreatic cancer

Induction of anti-tumor immunity in pancreatic ductal adenocarcinoma (PDA) is an unresolved challenge. Systematic investigation of the microenvironment of primary pancreatic tumors revealed a role of endocrine Langerhans islets in the coordination of immune activation. We found that intratumoral β-cells, regulated via STAT3, secrete C-C motif chemokine ligand 27 (CCL27) and thereby promote a TH1 phenotype in the microenvironment resulting in an enhanced T cell infiltration and prolonged patient survival. The local effect can be abrogated in a patient-based human explant model by inhibition of the CCL27 receptor CCR10. This defense mechanism is paralleled by an impaired metabolic function of Langerhans islets with reduced insulin levels resulting in a dysregulation of glycemic control in patients. Based on these findings, screening of PDA cases (n= 2264) led to the identification of type 2 diabetes mellitus (T2DM) and extractable glycated haemoglobin (HbA1c) levels as response markers for neoadjuvant chemotherapy with fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX). Collectively these data provide insights into the interconnection of T2DM and PDA, and link declining glycemic control to therapeutic efficacy, which can be utilized as a tool for clinical decision-making and improve patient management.

The Comparative Effectiveness of Phaleria macrocarpa (Scheff.) Boerl. Pericarp Ethanol Extract and Metformin in Reducing Blood Sugar Levels and Ameliorating the Langerhans Islets Degeneration in Diabetic Rat Models

Phaleria macrocarpa (Scheff.) Boerl. has been widely used in the treatment of diabetes mellitus but its effectiveness is still inconclusive so it needs to be compared with standard drugs such as metformin. This study aims to analyze the effects of P. macrocarpa fruit extracts on blood sugar levels and the repairing of the pancreatic Langerhans islets of diabetic rat models. The study was conducted experimentally by pre and post-test design with a control group. Thirty white rats were divided into 6 groups. All rats were treated with 40 mg/200 g BW of streptozotocin (STZ) to induce hyperglycemia, except group I. Group II as a negative control was given with aquadest. Group III, IV, and V were given with ethanol extract of P. macrocarpa pericarps at doses of 200, 250, and 300 mg/200 g BW/day, respectively. Group VI was given with metformin at a dose of 150 mg/200 g BW/day. On the 22nd day of treatment, blood specimens were taken for examination of fasting blood sugar levels and pancreatic organs were analyzed for histopathological examination of the islets of pancreatic Langerhans. The data were statistically analyzed with α<0.05; CI95%. Paired sample t-test results showed a significant decrease in blood sugar levels before and after treatment in group V (p-value=0.048). One way anova and post hoc Least Significant Difference (LSD) test results showed a significant difference in mean blood sugar levels after the final treatment between groups I and II (p-value=0.013), I and III (p-value=0.004), I and IV (p-value=0.002), I and VI (p-value=0.000), II and VI (p-value=0.031), and V with VI (p-value=0.005); one way anova and post hoc LSD test results showed a significant difference in the mean area of islets of pancreatic Langerhans between group I and all treatment groups (p-value=0.000), II with V and VI (p-value=0.000 and 0.009), III with V and VI (p-value=0.000 and 0.001), and IV with V (p-value=0.003). It can be concluded that the extract of P. macrocarpa pericarps showed a hypoglycemic effect and repaired the damage in Langerhans islets of STZ-induced rat in a dose-dependent manner.

Effects of Patulin Treatment on Zebrafish (Danio rerio) Internal Organs

Patulin is a common contaminant of many food products which are part of humans or animals daily nutrition: fruits and fruit products, cereals, diary products and sausages. In the present study, adult zebrafish were divided in 2 groups: Control and patulin-treated group which was exposed to patulin (70 �g/L) for 7 days. Histological alterations of the control and patulin-treated group were examined and compared, with emphasis on liver, kidney, pancreas, intestine, brain and myocardium. While the Control group had no histological alterations, the patulin-exposed zebrafish show severe hepatocyte alteration, medium to severe degeneration of urinary epithelium, enterocytes hyalinosis, partial coagulation necrosis of the Langerhans islets and myocardial edema.

Pathamorphological changes of cats pancreata under acute pancreatitis

From among a great number of digestive system diseases in domestic animals there is pancreatitis which is caused by an early zymogenesis in the acinar cells. The problem of studying the structural organization of a pancreata in sick cats is topical because of a progressive spreading of pancreatitis in domestic animals. Thus, the purpose of the research was to study out the morphological changes of cats pancreata under acute pancreatitis. Working with vertebrate animals we were guided by “European Convention for the Protection of Vertebtate Animals used for Experimental and other Scientific Purposes” (Strasbourg, 1986). The results of the histological examination of cats pancreata under acute pancreatitis show some pathological changes both in endocrine and exocrine pancreas. Such changes were manifested in necrosis of exocrine pancreatitis as well as in spreading and swelling of acinar space, that testified to the infancy of an inflammatory process. Some dystrophic changes, followed by karyolysis, were found in the focus of tissue nicrosis. Pancreatocyte cytoplasm was cloudy, its basal and apical zones were obscure, clearly defined interstitial tissue swelling was found between the particles and unequal swelling was found inside the particles. Intercellular space was exaggerated. Morphometrically in a group of sick animals was detected an increase in specific weihgt of stromal component (р<0,05),which equalled 22,44±0,24 %, in a control group it equalled 17,78±0,15 %. Some hemorrhage and distrophicvally changed hormone- active cells as well as nonregular distribution of cells were detected under a histological examination of Langerhans islets. In most islets the cells had swelled vacuolar cytoplasm. While analyzing the morphometric indices it was stated that the cats exocrine pancreas under acute pancreatitis was 1.12 as large and occupied 48258,05±135,07 mkm2, (97,88±0,05 %). The cats endocrine pancreas under this pathology occupied 6858,85±315,05 mkm2, (2,12±0,05 %). In cats of a control group this index equalled 6784,71±285,04 mkm2 (1,95±0,06 %). The diameter of sick cats acinus as well as of Langerhans islets equalled respectively 31,85±0,05 and 71,81±2,45 mkm, which reliably (р<0,001) was 1.13 and 1.15 as large. In clinically healhty cats these indices are 28,12±0,11; 70,20±2,48 mkm.

The combined effect of magnetic and electric fields using on/off infrared light on the blood sugar level and the diameter of Langerhans islets of diabetic mice

Background and Aim: At present, diabetes is treated with oral antidiabetic medicines, such as sulfonylureas and thiazolidine, as well as insulin injection. However, these methods have several shortcomings. Therefore, alternatives for treating diabetes mellitus (DM) are needed. This study aims to determine the combined effect of magnetic and electric fields on blood sugar levels and the diameter of Langerhans islets of diabetic mice. Materials and Methods: Induction of DM in mice was carried out by administering lard for 2 weeks and continued with an intraperitoneal injection of streptozotocin, dissolved in a 4.5 pH citrate buffer, and administered in a dose of 30 mg/kg bodyweight for 5 days. Treatments were used in combination with magnetic and electric fields using on/off infrared light. Blood samples were pipetted through the tip of mice's tails to establish the blood sugar level for each individual mouse. Histology preparation of the pancreas organ was affected using the histology standard as well as hematoxylin and eosin staining methods. Langerhans islet diameter data were analyzed using analysis of variance followed by Duncan's multiple range test. Data analysis was performed at α=0.05. Results: The results showed that the combined treatment of permanent magnetic and unidirectional electric fields (PS) caused changes in blood sugar levels that were not significantly different from the normal control group. The PS treatment improved the diameter of the Langerhans islets but not to a significant degree compared to other treatments. Conclusion: The use of PS treatment is effective for reducing the blood sugar levels of diabetic mice and improving the diameter of their Langerhans islets.

Moderate Intensity of Physical Exercise increased Β (Beta) Cell and Size of Langerhans Islets in Streptozotocin Induced Diabetes Mellitus Rats

Background: The death of β cells Langerhans islets in Diabetes Mellitus (DM) can cause loss of Langerhans islet function and worsen the progression of DM. Physical exercise plays a major part in DM treatment.Aim: to observe the effect of moderate intensity exercise to β (beta) cell numbers and Langerhans islets area size in Streptozotocin (STZ) induced diabetes in rats.Methods: Thirty adult male Wistar rats (Rattusnorvegicus) divided into 3, Group 1 as the control, Group 2 received 35 mg/kg streptozotocin induction treatment, Group 3 received 35 mg/kg streptozotocin induction and physical exercise, swimming, with moderate intensity 70% from the swimming maximal ability, 9% of body weight load, 4 times a week for 4 weeks. Datas collected were in the form of histopathology slide of pancreatic tissue after receiving treatment for 28 days.Results: There are significant differences of β-cell pancreas number between group K1 and K2 (p<0,001), group K2 and to K3 (p<0,001). No significant difference between group K1 and K3 (p=0,102). The Langerhans islets area sizes of pancreas tissue between group K1, K2, and K3 are significantly different (p<0,001).Conclusion: This study shows moderate-intensity physical exercise can increase the number of β cell and average area size of Langerhans islets. The effect of physical exercise depends on the intensity of exercise and the capacity of pancreatic function left of the diabetic.

Moderate Intensity of Physical Exercise increased Β (Beta) Cell and Size of Langerhans Islets in Streptozotocin Induced Diabetes Mellitus Rats

Background: The death of β cells Langerhans islets in Diabetes Mellitus (DM) can cause loss of Langerhans islet function and worsen the progression of DM. Physical exercise plays a major part in DM treatment.Aim: to observe the effect of moderate intensity exercise to β (beta) cell numbers and Langerhans islets area size in Streptozotocin (STZ) induced diabetes in rats.Methods: Thirty adult male Wistar rats (Rattusnorvegicus) divided into 3, Group 1 as the control, Group 2 received 35 mg/kg streptozotocin induction treatment, Group 3 received 35 mg/kg streptozotocin induction and physical exercise, swimming, with moderate intensity 70% from the swimming maximal ability, 9% of body weight load, 4 times a week for 4 weeks. Datas collected were in the form of histopathology slide of pancreatic tissue after receiving treatment for 28 days.Results: There are significant differences of β-cell pancreas number between group K1 and K2 (p<0,001), group K2 and to K3 (p<0,001). No significant difference between group K1 and K3 (p=0,102). The Langerhans islets area sizes of pancreas tissue between group K1, K2, and K3 are significantly different (p<0,001).Conclusion: This study shows moderate-intensity physical exercise can increase the number of β cell and average area size of Langerhans islets. The effect of physical exercise depends on the intensity of exercise and the capacity of pancreatic function left of the diabetic.