Endocrine Research Articles

241-OR: Preservation of Islet Graft Function and Blood Glucose Control after Total Pancreatectomy with Islet Autotransplantation in Patients with Chronic Pancreatitis and Intractable Pain—Nine-Year Follow-up

Background: Total pancreatectomy is a last resort treatment for patients with chronic pancreatitis and intractable abdominal pain, however its utility has been hampered by the uncertain endocrine outcomes of islet transplantation and risk of postsurgical diabetes. Here, we present our 9-year clinical results after total pancreatectomy and islet transplantation. Materials and Method: Forty-one patients with chronic or recurrent acute pancreatitis were treated with TPIAT over the last 9 years at the University of Chicago Medical Center. There were 15 male and 26 female with a median age of 33 (6-65) and with median BMI of 25 (17-39). Five (12%) patients were already diabetic prior to surgery. Islet isolation was performed at a local laboratory compliant with current Good Manufacture Practice regulations. Islet purification was implemented in 4 (10%) cases to reduce islet pellet volume below 20mL for intraportal infusion. Results: All patients required opioids for pain control prior to surgery. Most of the patients (93%) reported resolution of pancreatic-type pain by postoperative year one. The number of patients requiring opioids for different type or location of pain declined over time from 13 (31%) at 1 year to 5 (12%) at 5 years after TPIAT. During TPIAT patients received on average 211,000±111,000 islet equivalents (IEQ), 2,500±1,600,). The majority of patients (95%) maintained endocrine beta cell function during follow up (serum c-peptide >0.5ng/ml). Over 40% of patients maintained long-term insulin independence: 44% (15/34) at 1-year and 45% (5/11) at 5-year follow-up. Conclusions: TPIAT successfully provided pancreatic pain resolution of pancreatic pain and preservation of the endocrine beta cell function in majority of the patients with no mortality. Islet autotransplantation prevented diabetes in over 40% of patients. Disclosure W.Lin: None. L.Wang: None. M.Tibudan: None. R.Barth: None. J.Fung: None. P.Witkowski: Advisory Panel; Vertex Pharmaceuticals Incorporated, Novartis. M.Ogledzinski: None. S.Gondek: None. K.Milejczyk: None. B.Juengel: None. L.Potter: None. P.J.Bachul: None. L.Basto: None. L.Perea: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (P30DK020595)

348-OR: Differentiation of Adult Islet Cell Precursors into ß- and α-like Cells for Islet Transplantation

Advances in protocols to convert human embryonic and inducible pluripotent stem cells (hESCs and iPSCs) into pancreatic β cells has allowed us to generate islet cell organoids in culture for potential use in islet cell transplantation. Here, we demonstrate that dedifferentiated β cells and/or NGN-/RGS16+ islet cell precursors (ICPs) can be harvested from adult pancreatic tissue and converted into β- and α-like cells. In this study, we used ICPs derived from COBE bag pancreatic tissue remnants from organ donors to produce islet cell organoids capable of releasing both insulin and glucagon in response to high (16.7 mM) and low (2.8 mM) glucose conditions, respectively. These organoids displayed zinc-containing granule staining by dithizone and exhibited GSIS with stimulation indices comparable to human islets. ICPs produced genetic profiles similar to hESC-derived endocrine progenitor cells at stages 5-7 (S5-7). Using small molecule ISX9 and GSK/DYRK inhibitors GNF and harmine to induce and activate calcineurin (CN)/NFAT signaling, we were able to expand and differentiate ICPs into β- and α-like cells. CN/NFAT upregulated genes that promote cell cycle and proliferation (S5) and islet cell differentiation genes (S5-7). Islet cell type fate and function could be modulated by hedgehog/GLI signaling. Whereas introduction of sonic hedgehog (Shh) inhibitor SANT-1 at S5 favored production of β-like cells, Shh signaling agonists promoted differentiation to α-like cells up to S7. Overall, these results indicate that adult ICPs can be harvested from donor tissue and expanded for differentiation into functional β- and α-like cells. The capability to expand and differentiate adult ICPs could potentially provide an unlimited supply of islet organoid tissue for islet cell transplantation. Disclosure C.Darden: None. J.Kuncha: None. J.D.Mattke: None. B.Naziruddin: None. M.C.Lawrence: None. Funding Baylor Scott & White Health

6-LB: GPR119 Agonist PRM A Increases Glucagon Response to Hypoglycemia in Rats

Glucagon (Gcg) is crucial in the counter-regulatory response (CRR) to hypoglycemia yet this is severely impaired in T1D. This pathophysiology was recognized 50 years ago, but only recently have drug targets emerged to amplify Gcg CRR in T1D. One promising target is the receptor GPR119, expressed in gut endocrine cells and pancreatic islets with highest expression on α-cells, 10-fold greater than on β-cells. In the current study, a GPR119 agonist (PRM A) was given by oral gavage at doses of 3, 10 and 30 mg per kg (mpk), to rats (Sprague-Dawley, groups of 8) two hours prior to induction of hypoglycemia by an insulin tolerance test (ITT), using a dose of 1.25 Units per kg, given by intra-peritoneal injection at t=0 min. A vehicle-treated (V) control and a positive comparator group, given the GPR119 agonist MBX-2982 (10 mpk) were also studied. MBX-2982 is currently being used in a clinical trial to assess its effect on Gcg CRR in volunteers with T1D challenged with a hypoglycemic clamp. In rats in the current study, severe hypoglycemia was induced during the ITT; blood glucose nadir was achieved by 60 min in association with peak insulin ≥ 100 µU/ml. Glucose and insulin were similar across groups. The healthy V rats mounted a normal Gcg CRR, with a peak value of 26±10 pM, 5-fold above baseline. Pre-treatment with PRM A significantly amplified Gcg CRR relative to V (to 86±17, 79±18, and 85±12 pM; at 3, 10, and 30 mpk; p<0.0001 vs V). The Gcg AUC during the ITT was nearly 50% greater with all doses of PRM A (p<0.05 vs V) and the peak Gcg CRR was shifted earlier (p<0.01 vs V). MBX-2982 pre-treated rats, relative to V, trended to a higher peak (49±14 vs 26±10 pM) and AUC Gcg (7292±2039 vs 6855±1306 pM*h), but neither difference was significant, whereas the differences for PRM A were strongly significant for time and treatment. In summary, PRM A, a potent GPR119 agonist, tripled peak Gcg CRR during an ITT in healthy rats, affirming that the target of GPR119 holds promise as a novel means to mitigate the dangerous risk of hypoglycemia for individuals with T1D. Disclosure D. W. K. Kwok: None. D. Alexander: None. N. R. A. Beeley: None. D. Kelley: Consultant; Pramana Pharmaceuticals, Inc, Kallyope. Funding Pramana Pharmaceuticals Inc.

69-OR: Multiancestry Genome-Wide Association Study Reveals Distinct Biological Pathways and Cell Types Driving Type 2 Diabetes Risk with Heterogeneous Effects across Diverse Populations

The Type 2 Diabetes Global Genomics Initiative aggregated genome-wide association studies (GWAS) of type 2 diabetes (T2D) in 428,452 affected individuals and 2,107,149 controls from five major ancestries (39.7% non-European ancestry) to enhance power for locus discovery and improve understanding of the pathophysiological basis of the disease. We identified 1,289 independent association signals (P < 5 x 10-8) at 611 loci, of which 145 were previously unreported. We applied K-means clustering to the signals based on their associations with 37 cardiometabolic traits and identified eight clusters with distinct profiles. Three clusters were related to insulin secretion and had a positive, negative, or no effect on proinsulin levels. These clusters were significantly enriched (P < 0.05/222, Bonferroni correction for the number of cell types) for epigenomic annotations from single-cell ATAC-seq data in pancreatic islets but had different enrichment in pancreatic ductal cells and intestinal endocrine cells. The remaining five clusters related to insulin resistance (IR) physiology: increased body fat; unfavourable fat distribution (decreased gluteofemoral fat and increased visceral fat); obesity (increased body mass index); lipodystrophy (increased fasting insulin and decreased body fat); and liver lipid metabolism (increased liver fat and liver enzymes). IR clusters showed more diverse patterns of enrichment: obesity in adrenal cells; fat distribution in endothelial cells and pericytes in blood vessels; and lipodystrophy in adipocytes. T2D signals were more strongly enriched for ancestry-correlated heterogeneity in effect sizes in insulin secretion clusters than IR clusters. These data demonstrate distinct clusters of T2D association signals representing different trajectories to disease with observable differences in effect sizes across ancestry groups. Disclosure K.Suzuki: None. Diamante consortium: n/a. Va million veteran program: n/a. J.B.Meigs: Consultant; Quest Diagnostics. M.I.Mccarthy: Employee; Genentech, Inc., Stock/Shareholder; Roche Pharmaceuticals. A.Mahajan: Employee; Genentech, Inc. J.M.Mercader: None. C.Spracklen: None. M.Boehnke: None. M.Vujkovic: None. J.I.Rotter: None. K.Hatzikotoulas: None. B.F.Voight: None. E.Zeggini: None. A.Morris: None. Type 2 diabetes global genomics initiative: n/a. L.Southam: None. X.Yin: None. K.Lorenz: None. R.Mandla: None. H.J.Taylor: None. A.Huerta: None. N.W.Rayner: None.

85-OR: Swi/Snf Controls Transcriptional Programs Required for ß-Cell Development and Postnatal Islet Function

A key feature of diabetes is insufficient functional β-cell mass. Strategies to augment functional β-cell mass include directed differentiation of stem cells towards a β-cell fate, which requires extensive knowledge of transcriptional programs governing differentiation in vivo. Pdx1, an essential transcription factor involved in β-cell differentiation, dynamically recruits coregulators to drive different gene expression programs. A recent study identified the ATP-dependent Swi/Snf chromatin remodeling complex as an important Pdx1-interacting partner. In the developing pancreas, conditional removal of the Brg Swi/Snf ATPase subunit compromised final pancreas mass, and loss of both ATPase subunits, Brg1 and Brm, led to glucose dyshomeostasis. While Swi/Snf is essential during early pancreas development and mature β-cell function, the role of Swi/Snf during endocrine cell development has yet to be explored. Here, we generated a conditional knockout of either Brg1 (Brg1ΔendoBrm+/-), Brm (Brg1Δendo/+Brm-/-), or both subunits (DKOΔendo) during endocrine development using Neurogenin 3 Cre. Four-week-old Brg1ΔendoBrm+/- mice are glucose intolerant, hyperglycemic, and hypoinsulinemic, with no phenotype observed in Brg1Δendo/+Brm-/-mice. Impaired glucose homeostasis of Brg1ΔendoBrm+/- mice was due in part to reduced islet number, impaired insulin secretion, and altered gene expression programs. DKOΔendo mice have not been found at weaning; however, postnatal day 6 DKOΔendo mice are severely hyperglycemic with reduced plasma insulin levels. Single-cell RNA-Seq of embryonic day 15.5 lineage-labeled cells revealed reduced insulin and glucagon transcript in the β-cell and α-cell clusters, respectively, in both Brg1ΔendoBrm+/- and DKOΔendo mice and reduced Neurogenin 3­ transcript in DKOΔendo endocrine progenitor clusters. These data suggest Swi/Snf plays a critical role in governing gene-expression programs essential for endocrine cell development. Disclosure R.K.Davidson: Employee; Eli Lilly and Company. S.Kanojia: None. M.E.Osmulski: None. J.Spaeth: None. Funding National Institutes of Health (R01DK129287, R03DK127129)

231-OR: Reduced NKX2-2 Expression Enhances Insulin Secretion by Primary Human ß-Cells

Pancreatic islet endocrine cell phenotype and function are tightly regulated by transcription factor (TF) regulatory networks. In a mouse model of pancreas organogenesis, the key islet-enriched TF NKX2.2 governs both β and α cell specification. Further, loss of NKX2.2 in adult mouse β cells results in glucose intolerance, reduced insulin content, and polyhormonal β cells, demonstrating its importance in the maintenance of β cell phenotype. To understand the undefined role of NKX2.2 in adult human islets, we utilized adenoviral delivery of CRISPR and shRNA constructs in our primary human pseudoislet system to knockout (gNKX2-2) or knockdown (shNKX2-2) NKX2-2 in islet cells, respectively (n=4-6 donors without diabetes). Immunofluorescence analyses of gNKX2-2 pseudoislets demonstrated loss of NKX2.2 signal across β (81 ± 2.0%; p<0.001), α (58 ± 5.5%; p=0.001), and δ cells (83 ± 2.2%; p<0.001) compared to scrambled controls (gSCR). Surprisingly, functional assessment by dynamic perifusion revealed increased insulin secretion in gNKX2-2 versus gSCR pseudoislets measured as area under the curve in response to 16.7 mM glucose (6.64 ± 1.53 vs. 3.55 ± 1.53 ng/100 islet equivalents (IEQs); p=0.007) and cAMP-evoked potentiation with 16.7 mM glucose + 100 μM isobutylmethylxanthine (IBMX) (5.43 ± 0.50 vs. 3.15 ± 0.59 ng/100 IEQs p=0.003) without changes in total insulin content (gNKX2-2 vs. gSCR: 3.64 ± 0.75 vs. 4.78 ± 0.87 ng/IEQ, p=0.45). Furthermore, these findings were recapitulated in shNKX2-2 versus shSCR human pseudoislets (16.7 mM glucose: 10.17 ± 2.46 vs. 6.50 ± 2.51 ng/100 IEQs, p=0.02; 16.7 mM glucose + IBMX: 8.43 ± 1.31 vs. 4.21 ± 1.33 ng/100 IEQs, p=0.0002; insulin content: 6.18 ± 1.05 vs. 7.53 ± 1.26 ng/IEQ, p=0.36), where we observed a reduction in NKX2.2hi β (65 ± 10%; p=0.008), α (52 ± 5.5%; p=0.003), and δ cells (83 ± 4.6%; p=0.003). Collectively, our data indicate a critical role of NKX2-2 in the maintenance of primary adult human β cell function and suggest differential roles in islet function across species. Disclosure Y.D.Pettway: None. S.Parker: Research Support; Pfizer Inc. A.C.Powers: None. M.Brissova: None. J.Walker: None. C.Dai: None. R.Aramandla: None. A.L.Hopkirk: None. C.Reihsmann: None. C.Davis: None. R.Jenkins: None. L.Sussel: None.

Endocrine pathologies in the conditions of chemotherapy

BACKGROUND. Cancer is the leading cause of death in the world. Chemotherapy is the most effective and in some cases the only method of treating oncopathology. At the same time, chemotherapy can lead to a number of side effects, among which endocrine disorders are noted.
 OBJECTIVE. To investigate possible diseases of the endocrine system that develop during chemotherapy.
 MATERIALS AND METHODS. A review of literary sources.
 RESULTS AND DISCUSSION. In general, the statistics on the development of endocrine diseases during chemotherapy is limited and requires additional research to obtain a more accurate picture. Nevertheless, based on the data of the studied literature, it can be assumed that some of the patients who received chemotherapy developed the following endocrine disorders: hypothyroidism, Hashimoto’s thyroiditis, adrenal dysfunction (hyper- and hypocorticism), hypergonadotropic hypogonadism, diabetes mellitus.
 CONCLUSIONS. Endocrine diseases that develop as a result of chemotherapy can significantly worsen the patient’s quality of life, and given the fact that chemotherapy is vital and in some cases the only treatment for oncopathology, doctors should timely monitor carbohydrate metabolism, thyroid function and other markers of endocrine diseases. No less important are preventive measures, including rational nutrition and physical activity, the intensity of exercises and movements for wellbeing.

DNA origami-mediated plasmonic dimer nanoantenna-based SERS biosensor for ultrasensitive determination of trace diethylstilbestrol

Diethylstilbestrol (DES) is a threatening factor to the human endocrine system. Here, we reported a DNA origami-assembled plasmonic dimer nanoantenna-based surface-enhanced Raman scattering (SERS) biosensor for measuring trace DES in foods. A critical factor influencing the SERS effect is interparticle gap modulation of SERS hotspots with nanometer-scale accuracy. DNA origami technology aims to generate naturally perfect structures with nano-scale precision. Exploiting the specificity of base-pairing and spatial addressability of DNA origami to form plasmonic dimer nanoantenna, the designed SERS biosensor generated electromagnetic-enhancement and uniform-enhancement hotspots to improve sensitivity and uniformity. Owing to their high target-binding affinity, aptamer-functionalized DNA origami biosensors transduced the target recognition into dynamic structural transformations of plasmonic nanoantennas, which were further converted to amplified Raman outputs. A broad linear range from 10−10 to 10−5 M was obtained with the detection limit of 0.217 nM. Our findings demonstrate the utility of aptamer-integrated DNA origami-based biosensors as a promising approach for trace analysis of environmental hazards.

The effects of targeted vagus nerve stimulation on glucose homeostasis in STZ-induced diabetic rodents.

During type 1 diabetes, an autoimmune attack destroys pancreatic β-cells leading to the inability to maintain glucose homeostasis. These β-cells are neuroresponsive endocrine cells which normally secrete insulin partially in response to input from the vagus nerve. This neural pathway can be utilized as a point of therapeutic intervention by delivering exogenous stimulation to drive increased insulin secretion. In this study, a cuff electrode was implanted on the pancreatic branch of the vagus nerve just prior to pancreatic insertion in rats, and a continuous glucose meter was implanted into the descending aorta. Streptozotocin (STZ) was used to induce a diabetic state, and changes in blood glucose were assessed using various stimulation parameters. Stimulation driven changes in hormone secretion, pancreatic blood flow, and islet cell populations were assessed. We found increased changes in the rate of blood glucose change during stimulation which subsided after stimulation ended paired with increased concentration of circulating insulin. We did not observe increased pancreatic perfusion, which suggests that the modulation of blood glucose was due to the activation of b-cells rather than changes in the extra-organ transport of insulin. Pancreatic neuromodulation showed potentially protective effects by reducing deficits in islet diameter, and ameliorating insulin loss after STZ treatment.

Health status of coal industry workers

Health status of coal industry workers

Pharmacological inhibition of human EZH2 can influence a regenerative β-like cell capacity with in vitro insulin release in pancreatic ductal cells

BackgroundTherapeutic replacement of pancreatic endocrine β-cells is key to improving hyperglycaemia caused by insulin-dependent diabetes . Whilst the pool of ductal progenitors, which give rise to the endocrine cells, are active during development, neogenesis of islets is repressed in the human adult. Recent human donor studies have demonstrated the role of EZH2 inhibition in surgically isolated exocrine cells showing reactivation of insulin expression and the influence on the H3K27me3 barrier to β-cell regeneration. However, those studies fall short on defining the cell type active in transcriptional reactivation events. This study examines the role of the regenerative capacity of human pancreatic ductal cells when stimulated with pharmacological inhibitors of the EZH2 methyltransferase.ResultsHuman pancreatic ductal epithelial cells were stimulated with the EZH2 inhibitors GSK-126, EPZ6438, and triptolide using a 2- and 7-day protocol to determine their influence on the expression of core endocrine development marker NGN3, as well as β-cell markers insulin, MAFA, and PDX1. Chromatin immunoprecipitation studies show a close correspondence of pharmacological EZH2 inhibition with reduced H3K27me3 content of the core genes, NGN3, MAFA and PDX1. Consistent with the reduction of H3K27me3 by pharmacological inhibition of EZH2, we observe measurable immunofluorescence staining of insulin protein and glucose-sensitive insulin response.ConclusionThe results of this study serve as a proof of concept for a probable source of β-cell induction from pancreatic ductal cells that are capable of influencing insulin expression. Whilst pharmacological inhibition of EZH2 can stimulate secretion of detectable insulin from ductal progenitor cells, further studies are required to address mechanism and the identity of ductal progenitor cell targets to improve likely methods designed to reduce the burden of insulin-dependent diabetes.

ATP6AP2 is robustly expressed in pancreatic β cells and neuroendocrine tumors, and plays a role in maintaining cellular viability

ATP6AP2, also known as (pro)renin receptor, has been shown to be expressed in several tissues including pancreatic β cells. Whereas ATP6AP2 plays an important role in regulating insulin secretion in mouse pancreatic β cells, the expression profiles and roles of ATP6AP2 in human pancreatic endocrine cells and neuroendocrine tumor cells remain unclear. Here in this study, we investigated the expression profiles of ATP6AP2 in pancreatic endocrine cells, and found that ATP6AP2 is robustly expressed in pancreatic insulinoma cells as well as in normal β cells. Although ATP6AP2 was also expressed in low-grade neuroendocrine tumors, it was not or faintly detected in intermediate- and high-grade neuroendocrine tumors. Knockdown experiments of the Atp6ap2 gene in rat insulinoma-derived INS-1 cells demonstrated decreased cell viability accompanied by a significant increase in apoptotic cells. Taken together, these findings suggest that ATP6AP2 plays a role in maintaining cellular homeostasis in insulinoma cells, which could lead to possible therapeutic approaches for endocrine tumors.

BODY MASS INDEX (BMI) - PREDICTOR OF DISEASES ONSET AND REGULATOR OF PREVENTION?

The Body Mass Index (BMI) is a well-known tool for measuring normal, healthy weight. Nowadays, we can also use it as a prognostic factor for various diseases. Purpose: Our study aims to confirm or decline the correlation between body mass index and the onset of different diseases. Methods: The study was conducted among a random sample of 550 people (324 women and 226 men) from the district of Stara Zagora, Republic of Bulgaria. The participants in the study were aged between 18 and 65. The connection between BMI and the occurrence of diseases of different systems has been researched. A statistically significant relationship was found at p<0.05. The statistically significant influence of BMI on the occurrence of diseases is proved by the results of the ANOVA procedure. Results: The results give us reason to believe that not only obesity but also overweight is a risk of cardiovascular disease. This is evidenced by our study, according to which people with the highest average BMI (BMI = 28.72 kg/m2) have diseases of the cardiovascular system. People with a BMI around and above 25.87 kg / m2 often suffer from diseases of the endocrine system, and those with a BMI around 25.60 kg / m2 are at risk for diseases of the musculoskeletal system. Conclusions: BMI would find its daily implementation in the activities of every physician working in every field of medicine. BMI can be used as a tool to predict the onset of disease and a regulator of prevention.

EPIDEMIOLOGICAL FEATURES OF COMORBID PATHOLOGY IN COMBATANTS WITH ARTERIAL HYPERTENSION

Objective: Determination of the prevalence of comorbid pathology in patients with arterial hypertension (AH) participants in modern armed conflicts in order to implement timely preventive measures in order to prolong their health for military service. Design and method: By design, the research was a passive retrospective one-time (cross-sectional) study. The medical charts of inpatient patients of 213 male combatants, aged 27-59 years, average age 45.0 ± 6.8 years, who underwent treatment during 2018-2021, were analyzed by the method of random sampling. The examined patients were stratified according to the stage of hypertension: 126 patients with hypertension stage I and 87 patients with hypertension stage II. Results: The most common comorbid diseases with hypertension in combatants were diseases of the circulatory system (DCS, 60%), diseases of the endocrine system, nutritional disorders and metabolic disorders (DES, 82%), diseases of the nervous system (DNS, 65%), musculoskeletal diseases ulcer system and connective tissue (59%), diseases of digestive organs (52%), anxiety and depressive disorders (85% and 97% of patients, respectively). The association of an increase in the frequency of various concomitant diseases with the second stage of hypertension was determined - in stage II hypertension, compared with stage I hypertension, DCS was diagnosed more often (98% and 33%, respectively, p < 0.05), DEC (86% and 78%, respectively, p < 0.05), DNS (respectively 77% and 56%, p < 0.05). And diseases of the genitourinary system were more often diagnosed with stage I hypertension (43% and 22%, respectively, p < 0.05). The higher frequency of diagnosis of DCS in stage II hypertension is caused by coronary heart disease (97% and 25%, respectively, p < 0.05). Conclusions: The most common comorbid diseases in military personnel with hypertension who are participants in modern armed conflicts are DCS, DES, DNS, diseases of the musculoskeletal system and connective tissue, diseases of the digestive organs, anxiety and depressive disorders. In order to prolong the health for military personnel with hypertension and participants in modern armed conflicts, measures for the secondary prevention of DCS (primarily coronary heart disease), DES, DNS, anxiety and depressive disorders are expedient.

Protocol development to further differentiate and transition stem cell-derived pancreatic progenitors from a monolayer into endocrine cells in suspension culture

The generation of functional β-cells from human pluripotent stem cells (hPSCs) for cell replacement therapy and disease modeling of diabetes is being investigated by many groups. We have developed a protocol to harvest and aggregate hPSC-derived pancreatic progenitors generated using a commercially available kit into near uniform spheroids and to further differentiate the cells toward an endocrine cell fate in suspension culture. Using a static suspension culture platform, we could generate a high percentage of insulin-expressing, glucose-responsive cells. We identified FGF7 as a soluble factor promoting aggregate survival with no inhibitory effect on endocrine gene expression. Notch inhibition of pancreatic progenitor cells during aggregation improved endocrine cell induction in vitro and improved graft function following implantation and further differentiation in mice. Thus we provide an approach to promote endocrine formation from kit-derived pancreatic progenitors, either through extended culture or post implant.

Chemical inhibitors of cyclin-dependent kinase (CDKi) improve pancreatic endocrine differentiation of iPS cells

Islet transplantation, including pancreatic beta cells, has become an approved treatment for type I diabetes. To date, the number of donors limits the availability of treatment. Induction of pancreatic endocrine cells from pluripotent stem cells including iPSCs in vitro offers promise as a solution, but continues to face problems including high reagent costs and cumbersome differentiation procedures. In a previous study, we developed a low-cost, simplified differentiation method, but its efficiency for inducing pancreatic endocrine cells was not sufficient: induction of endocrine cells is non-uniform, resulting in colonies containing relatively high ratio of non-pancreatic-related cells. Here, we applied cyclin-dependent kinase inhibitors (CDKi) within a specific time window, which improved the efficiency of pancreatic endocrine cell induction. CDKi treatment reduced the prevalence of multi-layered regions and enhanced expression of the endocrine progenitor–related marker genes PDX1 and NGN3 resulting in enhanced production of both INSULIN and GLUCAGON. These findings support a step forward in the field of regenerative medicine of pancreatic endocrine cells.

INHIBITORY EFFECT OF CARBOHYDRAZ ON SECRETORY ACTIVITY OF THE PANCREAS

Since the time of Ivan Petrovich Pavlov's work, it is known that the juice collected from the pancreatic fistula, when it is re-introduced into the duodenum, inhibits the secretion of the pancreas. Most recently, in the works of American, French and Japanese physiologists, this inhibition was associated with the fact that trypsinogen secreted in the pancreatic secretion and trypsin contained in the duodenal contents inhibit the release of the hormone cholicystokininpancreosimin by duodenal endocrine cells - a powerful stimulator of enzyme secretion by the pancreas. This explanation of the reverse reproduction of pancreatic secretion from the duodenum is recognized by most experts. In connection with the above, the study of this problem seems to be an urgent task.

Single-cell transcriptomic atlas of parathyroid adenoma and parathyroid carcinoma.

Primary hyperparathyroidism is typically characterized by monoclonal parathyroid tumors that secrete an excessive amount of parathyroid hormone (PTH). However, the underlying pathogenesis of tumorigenesis remain unclear. We performed single-cell transcriptomic analysis on five parathyroid adenomas (PA) and two PC samples. A total of 63909 cells were divided into 11 different cell categories; endocrine cells accounted for the largest proportion of cells in both PA and PC, and patients with PC had larger populations of endocrine cells. Our results revealed significant heterogeneity in PA and PC. We identified cell cycle regulators may play a critical role in the tumorigenesis of PC. Furthermore, we found that the tumor microenvironment in PC was immunosuppressive, and endothelial cells had the highest interactions with other cell types, such as fibroblast-musculature cells and endocrine cells. PC development may be stimulated by fibroblast-endothelial cell interactions. Our study clarifies the transcriptional signatures that underlie parathyroid tumors and offer a potential significant contribution in the study of pathogenesis of PC. This article is protected by copyright. All rights reserved.

GABA treatment does not induce neogenesis of new endocrine cells from pancreatic ductal cells

ABSTRACT Previous studies indicated that ductal cells can contribute to endocrine neogenesis in adult rodents after alpha cells convert into beta cells. This can occur through Pax4 mis-expression in alpha cells or through long-term administration of gamma-aminobutyric acid (GABA) to healthy mice. GABA has also been reported to increase the number of beta cells through direct effects on their proliferation, but only in specific genetic mouse backgrounds. To test whether GABA induces neogenesis of beta cells from ductal cells or affects pancreatic cell proliferation, we administered GABA or saline over 2 or 6 months to Sox9CreER;R26RYFP mice in which 60–80% of large or small ducts were efficiently lineage labeled. We did not observe any increases in islet neogenesis from ductal cells between 1 and 2 months of age in saline treated mice, nor between 2 and 6 months of saline treatment, supporting previous studies indicating that adult ductal cells do not give rise to new endocrine cells during homeostasis. Unlike previous reports, we did not observe an increase in beta cell neogenesis after 2 or 6 months of GABA administration. Nor did we observe a significant increase in the pancreatic islet area, the number of insulin and glucagon double positive cells, or cell proliferation in the pancreas. This indicates that the effect of long term GABA administration on the pancreas is minimal or highly context dependent.

The Regulated Secretion and Models of Intracellular Transport: The Goblet Cell as an Example.

Transport models are extremely important to map thousands of proteins and their interactions inside a cell. The transport pathways of luminal and at least initially soluble secretory proteins synthesized in the endoplasmic reticulum can be divided into two groups: the so-called constitutive secretory pathway and regulated secretion (RS) pathway, in which the RS proteins pass through the Golgi complex and are accumulated into storage/secretion granules (SGs). Their contents are released when stimuli trigger the fusion of SGs with the plasma membrane (PM). In specialized exocrine, endocrine, and nerve cells, the RS proteins pass through the baso-lateral plasmalemma. In polarized cells, the RS proteins secrete through the apical PM. This exocytosis of the RS proteins increases in response to external stimuli. Here, we analyze RS in goblet cells to try to understand the transport model that can be used for the explanation of the literature data related to the intracellular transport of their mucins.