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Turkish Journal of Medical Sciences 2023Type 1 diabetes mellitus (T1DM) is caused by the autoimmune-mediated destruction of insulin-producing cells (IPCs) and still has no effective cure. Better understanding...
BACKGROUND/AIM
Type 1 diabetes mellitus (T1DM) is caused by the autoimmune-mediated destruction of insulin-producing cells (IPCs) and still has no effective cure. Better understanding of the molecular mechanisms involved in the differentiation of embryonic stem cells (ESCs) into IPCs may help us improve the therapeutic strategies for treating T1DM. 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (Pfkfb1-4) are key regulators of glucose metabolism. Although Pfkfb3 has been shown to be required for the growth of early differentiated mouse ESCs (mESCs), more studies are needed to further assess the roles of Pfkfb isoenzymes in embryonic development and differentiation, particularly into specific cell types. In this study, we aimed to elucidate the changes in the expression of Pfkfb isoenzymes on the differentiation of mESCs into IPCs.
MATERIALS AND METHODS
A 3-step protocol was used to differentiate R1 and J1 mESCs into IPCs. The changes in the gene expression of MafA, MafB, Ins2, and Nkx6.1 (IPC specific markers) and Pfkfb1-4 were analyzed using real-time quantitative polymerase chain reaction (qPCR). Insulin expression and secretion were determined by immunofluorescence (IF) staining and the enzyme linked immunosorbent assay (ELISA), respectively.
RESULTS
Upon differentiation, the IPC specific markers in differentiated cells were upregulated. Continued differentiation was confirmed by the development of insulin-positive islet-like clusters that secreted insulin in response to glucose uptake. Expressions of the Pfkfb2 and Pfkfb3 isoenzymes were markedly increased in various stages of differentiation.
CONCLUSION
These findings suggest that Pfkfb2 and Pfkfb3 may impact the differentiation of mESCs into IPCs and the regulation of the insulin response to glucose levels. This study also lays a foundation for researchers to further probe the roles of Pfkfb isoenzymes on the differentiation of mESCs into IPCs and may open new avenues for regenerative medicine.
Topics: Animals; Phosphofructokinase-2; Cell Differentiation; Mice; Mouse Embryonic Stem Cells; Isoenzymes; Insulin-Secreting Cells; Insulin
PubMed: 38813509
DOI: 10.55730/1300-0144.5725 -
Turkish Journal of Medical Sciences 2023Early identification of patients at risk for developing postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) may facilitate drain management. In...
BACKGROUND/AIM
Early identification of patients at risk for developing postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD) may facilitate drain management. In this context, it was aimed to examine the efficiency of the serum amylase (SA) value on postoperative day (PoD) 1 in predicting the occurrence of POPF.
MATERIALS AND METHODS
A total of 132 patients who underwent PD were studied. Occurrences of POPF were classified according to the International Study Group on Pancreatic Fistula classification as a biochemical leak (BL) or clinically relevant grade b/c POPF (CR-POPF). Receiver operating characteristic analysis identified a threshold value of SA on PoD 1 associated with POPF formation.
RESULTS
Overall, 66 (50%) patients had POPF, including 51 (38.7%) with BL and 15 with CR-POPF (11.3%). The threshold value of SA associated with the development of POPF was 120 IU/L (odds ratio [OR]: 3.20; p = 0.002). In the multivariate analysis, independent POPF risk factors were SA ≥120 IU/L, soft pancreatic texture, and high-risk pathology (i.e., duodenal, biliary, ampullary, islet cell, and benign tumors); SA ≥120 IU/L outperformed soft pancreatic texture and high-risk pathology in predicting POPF, respectively (OR: 2.22; p = 0.004 vs. OR: 1.37; p = 0.012 vs. OR: 1.35; p = 0.018). In a subset analysis according to gland texture (soft vs. hard), patients with soft pancreatic texture exhibited a significantly higher incidence of POPF (63.4% vs. 34.4%) and SA ≥120 IU/L (52.1% vs. 27.9%); SA <120 IU/L had a negative predictive value of 82.5% for developing POPF in patients with hard pancreatic texture (OR: 4.28, p = 0.028).
CONCLUSION
A SA value ≥120 IU/L on the day after PD, which is the strongest predictor for POPF, can be used as a biomarker of the occurrence of POPF. The advantage of SA measurement is that it can contribute to identifying suitable patients for early drain removal.
Topics: Humans; Pancreatic Fistula; Pancreaticoduodenectomy; Amylases; Male; Female; Retrospective Studies; Middle Aged; Aged; Postoperative Complications; Risk Factors; Predictive Value of Tests; Adult; Biomarkers; ROC Curve; Postoperative Period
PubMed: 38813023
DOI: 10.55730/1300-0144.5693 -
Cell Death & Disease May 2024High workload-induced cellular stress can cause pancreatic islet β cell death and dysfunction, or β cell failure, a hallmark of type 2 diabetes mellitus. Thus,...
High workload-induced cellular stress can cause pancreatic islet β cell death and dysfunction, or β cell failure, a hallmark of type 2 diabetes mellitus. Thus, activation of molecular chaperones and other stress-response genes prevents β cell failure. To this end, we have shown that deletion of the glucose-regulated protein 94 (GRP94) in Pdx1 pancreatic progenitor cells led to pancreas hypoplasia and reduced β cell mass during pancreas development in mice. Here, we show that GRP94 was involved in β cell adaption and compensation (or failure) in islets from leptin receptor-deficient (db/db) mice in an age-dependent manner. GRP94-deficient cells were more susceptible to cell death induced by various diabetogenic stress conditions. We also identified a new client of GRP94, insulin-like growth factor-1 receptor (IGF-1R), a critical factor for β cell survival and function that may mediate the effect of GRP94 in the pathogenesis of diabetes. This study has identified essential functions of GRP94 in β cell failure related to diabetes.
Topics: Animals; Insulin-Secreting Cells; Mice; Receptor, IGF Type 1; Diabetes Mellitus, Type 2; Cell Death; Receptors, Leptin; Membrane Glycoproteins; Mice, Inbred C57BL; Mice, Knockout
PubMed: 38811543
DOI: 10.1038/s41419-024-06754-y -
Scientific Reports May 2024Post-ERCP pancreatitis (PEP) is an acute pancreatitis caused by endoscopic-retrograde-cholangiopancreatography (ERCP). About 10% of patients develop PEP after ERCP. Here...
Post-ERCP pancreatitis (PEP) is an acute pancreatitis caused by endoscopic-retrograde-cholangiopancreatography (ERCP). About 10% of patients develop PEP after ERCP. Here we show that gamma-glutamyltransferase 1 (GGT1)-SNP rs5751901 is an eQTL in pancreatic cells associated with PEP and a positive regulator of the IL-6 amplifier. More PEP patients had the GGT1 SNP rs5751901 risk allele (C) than that of non-PEP patients at Hokkaido University Hospital. Additionally, GGT1 expression and IL-6 amplifier activation were increased in PEP pancreas samples with the risk allele. A mechanistic analysis showed that IL-6-mediated STAT3 nuclear translocation and STAT3 phosphorylation were suppressed in GGT1-deficient cells. Furthermore, GGT1 directly associated with gp130, the signal-transducer of IL-6. Importantly, GGT1-deficiency suppressed inflammation development in a STAT3/NF-κB-dependent disease model. Thus, the risk allele of GGT1-SNP rs5751901 is involved in the pathogenesis of PEP via IL-6 amplifier activation. Therefore, the GGT1-STAT3 axis in pancreas may be a prognosis marker and therapeutic target for PEP.
Topics: STAT3 Transcription Factor; Pancreatitis; Polymorphism, Single Nucleotide; Humans; Interleukin-6; Cholangiopancreatography, Endoscopic Retrograde; Animals; Quantitative Trait Loci; gamma-Glutamyltransferase; Mice; Male; Female; Middle Aged; Alleles; Cytokine Receptor gp130; Genetic Predisposition to Disease; NF-kappa B; Signal Transduction
PubMed: 38806529
DOI: 10.1038/s41598-024-60312-2 -
PloS One 2024Type 1 diabetes (T1D) is characterized by HLA class I-mediated presentation of autoantigens on the surface of pancreatic β-cells. Recognition of these autoantigens by...
Type 1 diabetes (T1D) is characterized by HLA class I-mediated presentation of autoantigens on the surface of pancreatic β-cells. Recognition of these autoantigens by CD8+ T cells results in the destruction of pancreatic β-cells and, consequently, insulin deficiency. Most epitopes presented at the surface of β-cells derive from the insulin precursor molecule proinsulin. The intracellular processing pathway(s) involved in the generation of these peptides are poorly defined. In this study, we show that a proinsulin B-chain antigen (PPIB5-14) originates from proinsulin molecules that are processed by ER-associated protein degradation (ERAD) and thus originate from ER-resident proteins. Furthermore, screening genes encoding for E2 ubiquitin conjugating enzymes, we identified UBE2G2 to be involved in proinsulin degradation and subsequent presentation of the PPIB10-18 autoantigen. These insights into the pathway involved in the generation of insulin-derived peptides emphasize the importance of proinsulin processing in the ER to T1D pathogenesis and identify novel targets for future T1D therapies.
Topics: Proinsulin; Autoantigens; Humans; Ubiquitin-Conjugating Enzymes; Endoplasmic Reticulum-Associated Degradation; Proteolysis; Diabetes Mellitus, Type 1; Antigen Presentation; Insulin-Secreting Cells
PubMed: 38787820
DOI: 10.1371/journal.pone.0287877 -
Diseases (Basel, Switzerland) Apr 2024Pancreaticolithiasis represents a rare phenomenon, being superimposed most of the time on a form of chronic pancreatitis of multifactorial etiology. Pancreaticolithiasis...
Pancreaticolithiasis represents a rare phenomenon, being superimposed most of the time on a form of chronic pancreatitis of multifactorial etiology. Pancreaticolithiasis is a late complication of the phenomenon of chronic pancreatitis. The reverberant inflammatory process, followed by the fibrotic degeneration of the pancreatic parenchyma, and pancreatic fluid stasis at the ductal level are factors that contribute to the phenomenon of calcium precipitation. This article describes the case of a patient with a diagnosis of pancreaticolithiasis (Wirsung duct lithiasis), a phenomenon superimposed on chronic pancreatitis of ethanolic cause (Rosemont classification). It was decided to perform surgery via the classical approach with the perfection of corporeo-caudal pancreatectomy and preservation of the splenic vessels (Kimura procedure) with pancreatico-jejunal anastomosis on the Roux-en-Y loop. The aim of this study is to identify the best method of treatment for pancreaticolithiasis. To enhance the case and provide a basis for standardization, a literature review was carried out, which included a total of six articles. The results of this study highlight that, currently, the management of symptomatic pancreaticolithiasis encompasses medical therapy (enzyme replacement therapy), interventional therapy (ESWL (extracorporeal shock wave lithotripsy) ± ERCP (endoscopic retrograde cholangiopancreatography), ERCP + sphincterotomy + stent insertion, and POP (oral pancreatoscopy)), and surgical treatment. In conclusion, based on the analysis conducted in this study, the size of the calculi present determines which is the suitable therapeutic care. Unlike stones over 0.5 cm, when surgery is explicitly advised for therapeutic purposes in the absence of endoscopic techniques, stones under 0.5 cm should be treated using endoscopic procedures.
PubMed: 38785741
DOI: 10.3390/diseases12050086 -
Nature Communications May 2024Pancreatic β cells secrete insulin in response to glucose elevation to maintain glucose homeostasis. A complex network of inter-organ communication operates to modulate...
Pancreatic β cells secrete insulin in response to glucose elevation to maintain glucose homeostasis. A complex network of inter-organ communication operates to modulate insulin secretion and regulate glucose levels after a meal. Lipids obtained from diet or generated intracellularly are known to amplify glucose-stimulated insulin secretion, however, the underlying mechanisms are not completely understood. Here, we show that a Drosophila secretory lipase, Vaha (CG8093), is synthesized in the midgut and moves to the brain where it concentrates in the insulin-producing cells in a process requiring Lipid Transfer Particle, a lipoprotein originating in the fat body. In response to dietary fat, Vaha stimulates insulin-like peptide release (ILP), and Vaha deficiency results in reduced circulatory ILP and diabetic features including hyperglycemia and hyperlipidemia. Our findings suggest Vaha functions as a diacylglycerol lipase physiologically, by being a molecular link between dietary fat and lipid amplified insulin secretion in a gut-brain axis.
Topics: Animals; Drosophila Proteins; Brain; Insulin Secretion; Insulin; Drosophila melanogaster; Insulin-Secreting Cells; Brain-Gut Axis; Lipase; Dietary Fats; Glucose; Fat Body; Lipoprotein Lipase; Male
PubMed: 38782979
DOI: 10.1038/s41467-024-48851-8 -
JCI Insight May 2024MAPK activating death domain (MADD) is a multifunctional protein regulating small GTPases RAB3 and RAB27, MAPK signaling, and cell survival. Polymorphisms in the MADD...
MAPK activating death domain (MADD) is a multifunctional protein regulating small GTPases RAB3 and RAB27, MAPK signaling, and cell survival. Polymorphisms in the MADD locus are associated with glycemic traits, but patients with biallelic variants in MADD manifest a complex syndrome affecting nervous, endocrine, exocrine, and hematological systems. We identified a homozygous splice site variant in MADD in 2 siblings with developmental delay, diabetes, congenital hypogonadotropic hypogonadism, and growth hormone deficiency. This variant led to skipping of exon 30 and in-frame deletion of 36 amino acids. To elucidate how this mutation causes pleiotropic endocrine phenotypes, we generated relevant cellular models with deletion of MADD exon 30 (dex30). We observed reduced numbers of β cells, decreased insulin content, and increased proinsulin-to-insulin ratio in dex30 human embryonic stem cell-derived pancreatic islets. Concordantly, dex30 led to decreased insulin expression in human β cell line EndoC-βH1. Furthermore, dex30 resulted in decreased luteinizing hormone expression in mouse pituitary gonadotrope cell line LβT2 but did not affect ontogeny of stem cell-derived GnRH neurons. Protein-protein interactions of wild-type and dex30 MADD revealed changes affecting multiple signaling pathways, while the GDP/GTP exchange activity of dex30 MADD remained intact. Our results suggest MADD-specific processes regulate hormone expression in pancreatic β cells and pituitary gonadotropes.
Topics: Insulin-Secreting Cells; Humans; Animals; Mice; Male; Gonadotrophs; Female; RNA Splice Sites; Cell Line; Insulin; Siblings; Exons; rab3 GTP-Binding Proteins; Hypogonadism
PubMed: 38775154
DOI: 10.1172/jci.insight.167598 -
International Medical Case Reports... 2024Fat overload syndrome is a rare and severe adverse reaction triggered by the infusion of a single source of lipid emulsion, resulting in elevated blood triacylglycerol...
BACKGROUND
Fat overload syndrome is a rare and severe adverse reaction triggered by the infusion of a single source of lipid emulsion, resulting in elevated blood triacylglycerol (TG) levels. The majority of literature reports focus on cases of fat overload syndrome in patients with mild symptoms. This case is significant because it demonstrates the diagnostic and therapeutic experience and provide valuable insights for the management for severe fat overload syndrome.
CASE PRESENTATION
We present a case report of a female patient who developed fat overload syndrome following prolonged and excessive infusion of lipid emulsion after colon resection surgery. In the setting of compromised immune function and malnutrition, the patient's pulmonary infection and respiratory distress symptoms have further exacerbated. Hence, in addition to severe pancreatitis, the patient has also contracted severe pneumonia. Upon admission, tracheal intubation, plasma exchange and blood perfusion were performed. Subsequently, comprehensive treatment was provided, including anti-infection, antispasmodic, acid suppression, enzyme inhibition, as well as targeted supportive measures to stabilize electrolytes and nutritional status. After treatment, there was a progressive reduction in blood lipid levels. After assessing the relevant risks, it was deemed necessary to perform an emergency computed tomography (CT)-guided percutaneous drainage tube placement procedure targeting the necrotic area of the pancreas while the patient was still intubated. Finally, the patient was discharged from the hospital.
CONCLUSION
The case highlights the association between fat overload syndrome and pancreatitis as well as the use of lipid emulsions and suggests the treatment strategies for severe fat overload syndrome.
PubMed: 38774710
DOI: 10.2147/IMCRJ.S463244 -
EGastroenterology Apr 2024Acute pancreatitis is a common inflammatory gastrointestinal disease without any successful treatment. Pancreatic exocrine acinar cells have high rates of protein...
Acute pancreatitis is a common inflammatory gastrointestinal disease without any successful treatment. Pancreatic exocrine acinar cells have high rates of protein synthesis to produce and secrete large amounts of digestive enzymes. When the regulation of organelle and protein homeostasis is disrupted, it can lead to endoplasmic reticulum (ER) stress, damage to the mitochondria and improper intracellular trypsinogen activation, ultimately resulting in acinar cell damage and the onset of pancreatitis. To balance the homeostasis of organelles and adapt to protect themselves from organelle stress, cells use protective mechanisms such as autophagy. In the mouse pancreas, defective basal autophagy disrupts ER homoeostasis, leading to ER stress and trypsinogen activation, resulting in spontaneous pancreatitis. In this review, we discuss the regulation of autophagy and its physiological role in maintaining acinar cell homeostasis and function. We also summarise the current understanding of the mechanisms and the role of defective autophagy at multiple stages in experimental pancreatitis induced by cerulein or alcohol.
PubMed: 38770349
DOI: 10.1136/egastro-2023-100057