scholarly journals Erythropoietin exposure of isolated pancreatic islets accelerates their revascularization after transplantation

2021 ◽  
Author(s):  
Maximilian M. Menger ◽  
Lisa Nalbach ◽  
Leticia P. Roma ◽  
Matthias W. Laschke ◽  
Michael D. Menger ◽  
...  
Keyword(s):  
Gene Expression ◽  
Pancreatic Islets ◽  
Isolated Islets ◽  
Vascular Endothelial ◽  
Isolated Pancreatic Islets ◽  
Dorsal Skinfold Chamber ◽  
Flow Cytometric ◽  
Clinical Islet Transplantation ◽  
Chamber Model ◽  
Endothelial Growth Factor

Abstract Aims The exposure of isolated pancreatic islets to pro-angiogenic factors prior to their transplantation represents a promising strategy to accelerate the revascularization of the grafts. It has been shown that erythropoietin (EPO), a glycoprotein regulating erythropoiesis, also induces angiogenesis. Therefore, we hypothesized that EPO exposure of isolated islets improves their posttransplant revascularization. Methods Flow cytometric, immunohistochemical and quantitative real-time (qRT)-PCR analyses were performed to study the effect of EPO on the viability, cellular composition and gene expression of isolated islets. Moreover, islets expressing a mitochondrial or cytosolic H2O2 sensor were used to determine reactive oxygen species (ROS) levels. The dorsal skinfold chamber model in combination with intravital fluorescence microscopy was used to analyze the revascularization of transplanted islets. Results We found that the exposure of isolated islets to EPO (3 units/mL) for 24 h does not affect the viability and the production of ROS when compared to vehicle-treated and freshly isolated islets. However, the exposure of islets to EPO increased the number of CD31-positive cells and enhanced the gene expression of insulin and vascular endothelial growth factor (VEGF)-A. The revascularization of the EPO-cultivated islets was accelerated within the initial phase after transplantation when compared to both controls. Conclusion These findings indicate that the exposure of isolated islets to EPO may be a promising approach to improve clinical islet transplantation.

scholarly journals Automated Analysis of Microscopic Images of Isolated Pancreatic Islets

2016 ◽  
Vol 25 (12) ◽  
pp. 2145-2156 ◽  
Author(s):  
David Habart ◽  
Jan Švihlík ◽  
Jan Schier ◽  
Monika Cahová ◽  
Peter Girman ◽  
...  
Keyword(s):  
Pancreatic Islets ◽  
Automated Analysis ◽  
Machine Learning Algorithms ◽  
Isolated Islets ◽  
Computer Assisted ◽  
Isolated Pancreatic Islets ◽  
Microscopic Images ◽  
Clinical Islet Transplantation ◽  
Islet Volume ◽  
Method R

Clinical islet transplantation programs rely on the capacities of individual centers to quantify isolated islets. Current computer-assisted methods require input from human operators. Here we describe two machine learning algorithms for islet quantification: the trainable islet algorithm (TIA) and the nontrainable purity algorithm (NPA). These algorithms automatically segment pancreatic islets and exocrine tissue on microscopic images in order to count individual islets and calculate islet volume and purity. References for islet counts and volumes were generated by the fully manual segmentation (FMS) method, which was validated against the internal DNA standard. References for islet purity were generated via the expert visual assessment (EVA) method, which was validated against the FMS method. The TIA is intended to automatically evaluate micrographs of isolated islets from future donors after being trained on micrographs from a limited number of past donors. Its training ability was first evaluated on 46 images from four donors. The pixel-to-pixel comparison, binary statistics, and islet DNA concentration indicated that the TIA was successfully trained, regardless of the color differences of the original images. Next, the TIA trained on the four donors was validated on an additional 36 images from nine independent donors. The TIA was fast (67 s/image), correlated very well with the FMS method ( R 2 = 1.00 and 0.92 for islet volume and islet count, respectively), and had small REs (0.06 and 0.07 for islet volume and islet count, respectively). Validation of the NPA against the EVA method using 70 images from 12 donors revealed that the NPA had a reasonable speed (69 s/image), had an acceptable RE (0.14), and correlated well with the EVA method ( R 2 = 0.88). Our results demonstrate that a fully automated analysis of clinical-grade micrographs of isolated pancreatic islets is feasible. The algorithms described herein will be freely available as a Fiji platform plugin.

scholarly journals Effect of directly acting anti-viral agents on immunological imprints in chronic HCV-4a patients: interleukin-10 and vascular endothelial growth factor genes expression level

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Iman S. Naga ◽  
Amel Abdel Fattah Kamel ◽  
Said Ahmed Ooda ◽  
Hadeer Muhammad Fath Elbab ◽  
Rania Mohamed El-Sharkawy
Keyword(s):  
Gene Expression ◽  
Vascular Endothelial Growth Factor ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Growth Factor ◽  
Angiogenic Factor ◽  
Vascular Endothelial ◽  
Wide Range ◽  
Chronic Hcv ◽  
Endothelial Growth Factor

Abstract Background Hepatitis C virus infection is a global health challenge with Egypt being one of the highly affected countries. IL-10 has been suggested as a suitable marker to assess necroinflammation and to monitor the progression of liver damage. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor playing a central role in many physiological as well as pathological processes. Several factors can be predictive of the response to treatment and achievement of SVR; some of which are host-related, and others are virus-related. The gene expression of IL-10 and VEGF have multiple effects for treatment response. The aim of the present work was to study the effect of treatment with directly acting agents (DAA) on the expression of VEGF and IL-10 genes in chronic hepatitis C virus-infected Egyptian genotype-4a patients. Twenty-five HCV subjects where evaluated for IL-10 and VEGF gene expression before and after treatment with DAA. Results IL-10 expression was downregulated in 92% of the cases. VEGF expression was heterogeneous showing spreading of values along a wide range with 64% of the cases being downregulated. Conclusion DAAs do not completely reverse the immunological imprints established upon chronic HCV infection.

scholarly journals Endocrine gland-derived vascular endothelial growth factor in rat pancreas: genetic expression and testosterone regulation

2008 ◽  
Vol 197 (2) ◽  
pp. 309-314 ◽  
Author(s):  
Angélica Morales ◽  
Sumiko Morimoto ◽  
Lorenza Díaz ◽  
Guillermo Robles ◽  
Vicente Díaz-Sánchez
Keyword(s):  
Gene Expression ◽  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Pancreatic Tissue ◽  
Endocrine Gland ◽  
Vascular Endothelial ◽  
Rinm5f Cells ◽  
Vegf Gene ◽  
Rat Pancreas ◽  
Endothelial Growth Factor

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) is an endothelial cell mitogen, expressed essentially in steroidogenic cells. Recently, the expression of EG-VEGF in normal human pancreas and pancreatic adenocarcinoma has been demonstrated. Epidemiologically, pancreatic carcinogenesis is more frequent in males than females, and given that androgen receptors and testosterone biotransformation have been described in pancreas, we hypothesized that testosterone could participate in the regulation of EG-VEGF expression. In this study, we investigated the regulation of EG-VEGF gene expression by testosterone in normal rat pancreatic tissue and rat insulinoma cells (RINm5F). Total RNA was extracted from rat pancreas and cultured cells. Gene expression was studied by real-time PCR and protein detection by immunohistochemistry. Serum testosterone was quantified by RIA. Results showed that EG-VEGF is expressed predominantly in pancreatic islets and vascular endothelium, as well as in RINm5F cells. EG-VEGF gene expression was lower in the pancreas of rats with higher testosterone serum levels. A similar effect that was reverted by flutamide was observed in testosterone-treated RINm5F cells. In summary, testosterone down-regulated EG-VEGF gene expression in rat pancreatic tissue and RINm5F cells. This effect could be mediated by the androgen receptor. To our knowledge, this is the first time that a direct effect of testosterone on EG-VEGF gene expression in rat pancreas and RINm5F cells is demonstrated.

scholarly journals Changes in Gene Expression in Rat Tissues during Toxoplasmosis

2021 ◽  
Vol 6 (2) ◽  
pp. 236-241
Author(s):  
E. S. Pashinskaya ◽  
Keyword(s):  
Gene Expression ◽  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Lung Tissue ◽  
Rat Tissues ◽  
Vascular Endothelial ◽  
Epidermal Growth ◽  
Endothelial Growth Factor ◽  
Brain Tissues

The purpose of the study is to study changes in gene expression in rat tissues during toxoplasmosis. Materials and methods. The experiment was conducted on 70 Wistar females weighing 170-220 grams. To achieve this goal, the expression of the proto-oncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI, vascular endothelial growth factor (VEGF) and anti-oncogene TP53 was determined in comparison with the reference genes β-actin (ACTB) and GAPDH by PCR analysis in the tissues of 10 healthy female rats and 60 infected with toxoplasma. RNA isolation was performed by the column method using the ReliaPrep RNA Cell Miniprep System (Promega Corporation, USA). The quality of the isolated RNA was evaluated spectrophotometrically. Reverse transcription was performed using M-MuLV RT (New England BioLabs Inc, USA). Primers specific to the genes were prepared using Primer3 and the NCBI Nucleotide database. Amplification was performed on a Real-Time PCR Detection System CFX96 thermal cycler (Bio-Rad, USA), using a qPCRmix-HS SYBR PCR mixture (Eurogen, Russia). Comparative expression of the studied genes was carried out after normalization of each of the samples to the level of the control genes GAPDH and ACTIN-β. Expression analysis was performed by qbase+ and CFX Maestro. Statistical processing of the obtained data was carried out using the program Statistica 10.0. Results and discussion. Toxoplasma increases the expression of survivin (BIRC5) in lung tissue to 0.013 relative units, in liver – to 0.038 relative units, in spleen – to 0.061 relative units, and in brain – to 0.050 relative units. VEGF expression in lungs increased to 0.034 relative units, in liver – to 0.041 relative units, in spleen – to 0.063 relative units, in brain tissues – to 0.080 relative units. There was an increase in the expression of ErbB-2/HER2-Neu in lung tissue to 0.436 relative units, in liver – to 0.259 relative units, in spleen – to 0.271 relative units, and in brain – to 0.131 relative units. GLI expression in lung tissues after toxoplasma infection increased to 0.113 relative units, in liver – to 0.188 relative units, in spleen – to 0.388 relative units, and in brain tissues – to 0.459 relative units. An increase in the expression of the anti-oncogene TP53 in the tissues of the lungs to 0.171 relative units, liver – to 0.295, spleen – to 0.408, and brain – to 0.259 relative units was revealed. Conclusion. It has been shown that toxoplasma can cause an increase in the expression of the proto-oncogenes survivin (BIRC5), epidermal growth factor (ErbB-2/HER2-Neu), GLI and vascular endothelial growth factor (VEGF) with simultaneous enhancement of the anti-oncogene TP53

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