Advancing Diabetes Research: A Novel Islet Isolation Method from Living Donors.

Pancreatic islet isolation is critical for type 2 diabetes research. Although -omics approaches have shed light on islet molecular profiles, inconsistencies persist; on the other hand, functional studies are essential, but they require reliable and standardized isolation methods. Here, we propose a simplified protocol applied to very small-sized samples collected from partially pancreatectomized living donors. Islet isolation was performed by digesting tissue specimens collected during surgery within a collagenase P solution, followed by a Lympholyte density gradient separation; finally, functional assays and staining with dithizone were carried out. Isolated pancreatic islets exhibited functional responses to glucose and arginine stimulation mirroring donors' metabolic profiles, with insulin secretion significantly decreasing in diabetic islets compared to non-diabetic islets; conversely, proinsulin secretion showed an increasing trend from non-diabetic to diabetic islets. This novel islet isolation method from living patients undergoing partial pancreatectomy offers a valuable opportunity for targeted study of islet physiology, with the primary advantage of being time-effective and successfully preserving islet viability and functionality. It enables the generation of islet preparations that closely reflect donors' clinical profiles, simplifying the isolation process and eliminating the need for a Ricordi chamber. Thus, this method holds promises for advancing our understanding of diabetes and for new personalized pharmacological approaches.

Oral or injectable semaglutide for the management of type 2 diabetes in routine care: A multicentre observational study comparing matched cohorts.

AIM: To investigate the real-world utilization and comparative clinical outcomes of injectable and oral semaglutide in individuals with type 2 diabetes (T2D) with the aim of enhancing understanding of the practical implications associated with choosing between these formulations. METHODS: New users of oral or injectable semaglutide were selected from a cohort of 14 079 initiators of glucagon-like peptide-1 receptor agonists. Propensity-score matching (PSM) was employed to create balanced groups, ensuring comparability. The analysis encompassed dose exposure, drug persistence, and clinical outcomes, including changes in glycated haemoglobin (HbA1c) and body weight, with up to 18 months' follow-up. RESULTS: We analysed two matched groups of 107 participants each, who comprised on average 63.6% men, aged 64 years, with diabetes duration of approximately 10 years, body mass index of 29 kg/m2 and HbA1c level of 7.7-7.8% (61-62 mmol/mol). The proportion of low, intermediate and high doses were similar with the oral and the injectable formulation. The change in HbA1c was similar between groups (-0.9% / -10 mmol/mol at 18 months) as was the proportion of individuals reaching HbA1c <6.5% (48 mmol/mol). The average change in body weight was similar in the two groups (-3.7 kg with injectable and -3.3 kg with oral at 18 months) but more new users of injectable semaglutide lost ≥5% body weight. Persistence on drug was longer with injectable than with oral semaglutide. CONCLUSION: In a real-world setting, improvements in HbA1c and body weight were similar after initiation of oral or injectable semaglutide. These results may be specific to the features of the matched cohorts under investigation, with limited generalizability to populations with different characteristics.

Physical Activity and Type 2 Diabetes: In Search of a Personalized Approach to Improving ß-Cell Function.

Type 2 diabetes mellitus (T2DM) is one of the most widespread diseases worldwide. Lifestyle interventions, including diet and physical activity (PA), are fundamental non-pharmacological components of T2DM therapy. Exercise interventions are strongly recommended for people with or at risk of developing or already with overt diabetes, but adherence to PA guidelines in this population is still challenging. Furthermore, the heterogeneity of T2DM patients, driven by differing residual ß-cell functionality, as well as the possibility of practicing different types and intensities of PA, has led to the need to develop tailored exercise and training plans. Investigations on blood glucose variation in response to exercise could help to clarify why individuals do not respond in the same way to PA, and to guide the prescription of personalized treatments. The aim of this review is to offer an updated overview of the current evidence on the effects of different regimens and modalities of PA regarding glucose sensing and ß-cell secretory dynamics in individuals with prediabetes or T2DM, with a special focus on ß-cell function.

Identification and Molecular Characterization of a Novel Large-Scale Variant (Exons 4_18 Loss) in the LDLR Gene as a Cause of Familial Hypercholesterolaemia in an Italian Family.

Next-generation sequencing (NGS) is nowadays commonly used for clinical purposes, and represents an efficient approach for the molecular diagnosis of familial hypercholesterolemia (FH). Although the dominant form of the disease is mostly due to the low-density lipoprotein receptor (LDLR) small-scale pathogenic variants, the copy number variations (CNVs) represent the underlying molecular defects in approximately 10% of FH cases. Here, we reported a novel large deletion in the LDLR gene involving exons 4-18, identified by the bioinformatic analysis of NGS data in an Italian family. A long PCR strategy was employed for the breakpoint region analysis where an insertion of six nucleotides (TTCACT) was found. Two Alu sequences, identified within intron 3 and exon 18, could underlie the identified rearrangement by a nonallelic homologous recombination (NAHR) mechanism. NGS proved to be an effective tool suitable for the identification of CNVs, together with small-scale alterations in the FH-related genes. For this purpose, the use and implementation of this cost-effective, efficient molecular approach meets the clinical need for personalized diagnosis in FH cases.

Circulating 1,5-Anhydroglucitol as a Biomarker of ß-cell Mass Independent of a Diabetes Phenotype in Human Subjects.

CONTEXT: During an asymptomatic prediabetic state, the functional ß-cell mass decreases to a critical threshold, triggering diabetes and related symptoms. To date, there are no reliable readouts able to capture in vivo a potential drop of the ß-cell mass. OBJECTIVE: Beside its use as a short-term marker of glycemic control, the deoxyhexose 1,5-anhydroglucitol was identified in rodents as a circulating biomarker of the functional ß-cell mass already in the asymptomatic prediabetic stage. The present study investigated the putative corresponding relevance of circulating 1,5-anhydroglucitol in different human cohorts. METHODS: We analyzed clinical and blood parameters in patients with established type 2 diabetes and subjects considered at high risk of developing diabetes, as well as patients with no history of diabetes scheduled for pancreaticoduodenectomy. RESULTS: Circulating 1,5-anhydroglucitol was reduced in type 2 diabetic patients, negatively correlating with fasting plasma glucose (P < 0.0001) and hemoglobin A1c (P < 0.0001). In healthy subjects, 1,5-AG levels positively correlated with body mass index (P = 0.004) and Homeostatic Model Assessment of Insulin Resistance %S (P < 0.03) and was particularly high in nondiabetic obese individuals, potentially accounting for compensatory ß-cell expansion. Patients with no history of diabetes undergoing pancreaticoduodenectomy exhibited a 50% reduction of circulating 1,5-anhydroglucitol levels following surgery leading to an acute loss of their ß-cell mass (P = 0.002), regardless their glucose tolerance status. CONCLUSION: In summary, plasma concentration of 1,5-anhydroglucitol follows the ß-cell mass and its noninvasive monitoring may alert about the loss of ß cells in subjects at risk for diabetes, an event that cannot be captured by other clinical parameters of glycemic control.

SGLT-2 inhibitors for treatment of heart failure in patients with and without type 2 diabetes: A practical approach for routine clinical practice.

Sodium-glucose cotransporter-2 inhibitors (SGLT-2i), initially studied and approved for the treatment of diabetes, are now becoming a promising class of agents to treat heart failure (HF) and chronic kidney disease (CKD), even in patients without diabetes. While the potential benefits in several diseases (usually treated by different medical specialties) is amplifying the interest in these drugs, their use in frail patients with multiple pathologies and on polypharmacy can be complex, requiring a composite multidisciplinary approach. Following a brief overview of the evidence supporting the benefits of SGLT-2i in patients with HF or CKD, we herein provide guidance for prescribing SGLT-2i in daily practice using a multidisciplinary approach. A shared treatment algorithm is presented for initiating an SGLT-2i in patients already being treated for diabetes and HF. Tools to prevent hypoglycemia, blood pressure drop, genital infections, euglycemic diabetic ketoacidosis and eGFR dip are also provided. It is hoped that this practical, multidisciplinary guidance for initiating SGLT-2i in patients with HF and/or CKD, whatever therapy they are currently on, can help to offer SGLT-2i to the largest population of patients possible to provide the most therapeutic benefit.

A novel low-density lipoprotein receptor variant in a Ukrainian patient: a case report and overview of the disease-causing low-density lipoprotein receptor variants associated to familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is characterized by high low-density lipoprotein-cholesterol levels and it is primarily caused by pathogenic/likely pathogenic variants (P/LPVs) in LDLR, APOB or PCSK9 genes. Next generation sequencing (NGS) technology allows the evaluation of more genes simultaneously, rising the diagnostic throughput of genomics laboratories. MATERIALS AND METHODS: We report a Ukrainian 37-year-old woman hypercholesterolemic since 2010. Despite a suggestive family history, FH was suspected only when the patient referred to the Endocrine and Metabolic Diseases Center of the Fondazione Policlinico Universitario A. Gemelli IRCCS in Rome. After specialist advice, genetic testing was offered to the patient at our Molecular and Genomic Diagnostics Unit. RESULTS: A targeted NGS-based pipeline highlighted a novel out-of-frame deletion in the LDLR gene. This variant has a clear deleterious effect on the LDLR protein and it can be classified as PV. CONCLUSIONS: The ideal model of care for FH is an evidence-based system aimed to provide the highest-quality health services to all FH patients. In fact, this study reports that the integrated care pathway adopted in our hospital for FH patients led successfully to the discovery of a novel LDLR PV in an Ukrainian patient. The finding of this LDLR variant allowed the clinical FH diagnosis in this patient and in her family, expanding the knowledge of FH-related genetic variants in the Ukrainian population.

Self-management in patients with type 2 diabetes: Group-based versus individual education. A systematic review with meta-analysis of randomized trails.

AIM: Patient education is an essential component of the treatment of type 2 diabetes mellitus (T2DM). The present meta-analysis was aimed at verifying the efficacy of group-based versus individual education for self-management in patients with T2DM. DATA SYNTHESIS: A Medline and Embase search up to January 1st, 2021, was performed, including Randomized Controlled Trials (RCT) with duration>6 months, enrolling patients with T2DM and comparing individual-based with group-based educational programs. The primary outcome was endpoint HbA1c; secondary endpoints were lipid profile, body weight, blood pressure, patients' adherence/knowledge, and quality of life. The weighed difference in means (WMD) and Mantel-Haenzel Odds Ratio (MH-OR), with 95% Confidence Interval (CI), were calculated. We retrieved 14 RCT. No significant between-group difference in HbA1c (WMD -0.39[-0.89; 0.09] mmol/mol, p = 0.11) was observed. At metaregression analyses, longer trial duration, higher baseline mean age and duration of diabetes, and lower baseline HbA1c were correlated with greater efficacy of group-based programs in reducing HbA1c. When analyzed separately, trials excluding insulin-treated patients showed a significant reduction of HbA1c in favor of group education. CONCLUSIONS: In patients with T2DM, group education has similar efficacy as individual education on glucose control. Group programs are associated with an improved quality of life and patients' knowledge. PROSPERO AND OSF REGISTRATION: ID243149.

Alpha-Lipoic Acid and Glucose Metabolism: A Comprehensive Update on Biochemical and Therapeutic Features.

Alpha-lipoic acid (ALA) is a natural compound with antioxidant and pro-oxidant properties which has effects on the regulation of insulin sensitivity and insulin secretion. ALA is widely prescribed in patients with diabetic polyneuropathy due to its positive effects on nerve conduction and alleviation of symptoms. It is, moreover, also prescribed in other insulin resistance conditions such as metabolic syndrome (SM), polycystic ovary syndrome (PCOS) and obesity. However, several cases of Insulin Autoimmune Syndrome (IAS) have been reported in subjects taking ALA. The aim of the present review is to describe the main chemical and biological functions of ALA in glucose metabolism, focusing on its antioxidant activity, its role in modulating insulin sensitivity and secretion and in symptomatic peripheral diabetic polyneuropathy. We also provide a potential explanation for increased risk for the development of IAS.

Pancreaticoduodenectomy model demonstrates a fundamental role of dysfunctional ß cells in predicting diabetes.

BACKGROUNDThe appearance of hyperglycemia is due to insulin resistance, functional deficits in the secretion of insulin, and a reduction of ß cell mass. There is a long-standing debate as to the relative contribution of these factors to clinically manifesting ß cell dysfunction. The aim of this study was to verify the acute effect of one of these factors, the reduction of ß cell mass, on the subsequent development of hyperglycemia.METHODSTo pursue this aim, nondiabetic patients, scheduled for identical pancreaticoduodenectomy surgery, underwent oral glucose tolerance tests (OGTT) and hyperglycemic clamp (HC) procedures, followed by arginine stimulation before and after surgery. Based on postsurgery OGTT, subjects were divided into 3 groups depending on glucose tolerance: normal glucose tolerance (post-NGT), impaired glucose tolerance (post-IGT), or having diabetes mellitus (post-DM).RESULTSAt baseline, the 3 groups showed similar fasting glucose and insulin levels; however, examining the various parameters, we found that reduced first-phase insulin secretion, reduced glucose sensitivity, and rate sensitivity were predictors of eventual postsurgery development of IGT and diabetes.CONCLUSIONDespite comparable functional mass and fasting glucose and insulin levels at baseline and the very same 50% mass reduction, only reduced first-phase insulin secretion and glucose sensitivity predicted the appearance of hyperglycemia. These functional alterations could be pivotal to the pathogenesis of type 2 diabetes (T2DM).TRIAL REGISTRATIONClinicalTrials.gov NCT02175459.FUNDINGUniversità Cattolica del Sacro Cuore; Italian Ministry of Education, University and Research; European Foundation for the Study of Diabetes.

Metformin Benefits: Another Example for Alternative Energy Substrate Mechanism?

Since the UK Prospective Diabetes Study (UKPDS), metformin has been considered the first-line medication for patients with newly diagnosed type 2 diabetes. Though direct evidence from specific trials is still lacking, several studies have suggested that metformin may protect from diabetes- and nondiabetes-related comorbidities, including cardiovascular, renal, neurological, and neoplastic diseases. In the past few decades, several mechanisms of action have been proposed to explain metformin's protective effects, none being final. It is certain, however, that metformin increases lactate production, concentration, and, possibly, oxidation. Once considered a mere waste product of exercising skeletal muscle or anaerobiosis, lactate is now known to act as a major energy shuttle, redistributed from production sites to where it is needed. Through the direct uptake and oxidation of lactate produced elsewhere, all end organs can be rapidly supplied with fundamental energy, skipping glycolysis and its possible byproducts. Increased lactate production (and consequent oxidation) could therefore be considered a positive mechanism of action of metformin, except when, under specific circumstances, metformin and lactate become excessive, increasing the risk of lactic acidosis. We are proposing that, rather than considering metformin-induced lactate production as dangerous, it could be considered a mechanism through which metformin exerts its possible protective effect on the heart, kidneys, and brain and, to some extent, its antineoplastic action.

Endocrine and Metabolic Insights from Pancreatic Surgery.

Although it is well established that diabetes can also develop as a result of diseases or maneuvers on the exocrine pancreas, the complex relationship between glucose disorders and underlying pancreatic disease is still debated. There is evidence that several features linked to pancreatic diseases can modify endocrine and metabolic conditions before and after surgery. However, pancreatic surgery provides a rare opportunity to correlate in vivo endocrine and metabolic pathways with ex vivo pancreatic samples, to examine the endocrine and metabolic effects of acute islet removal, and finally to clarify the pathogenesis of diabetes. This approach could therefore represent a unique method to shed light on the molecular mechanisms, predicting factors, and metabolic consequences of insulin resistance, islet plasticity, ß cell failure, and type 2 diabetes.

Postoperative hyperglycemia affects survival after gastrectomy for cancer: A single-center analysis using propensity score matching.

BACKGROUND: No data are present currently on the potential correlation between postoperative hyperglycemia and long-term outcomes after gastric surgery for cancer. The aim of this study was to investigate the effects of postoperative hyperglycemia on survival after curative gastrectomy for cancer. METHODS: All patients who underwent gastric surgery for cancer with curative intent were reviewed retrospectively. Diabetic patients and patients who needed pancreatic resection were excluded. In all patients, a prepared intravenous infusion of NaCl and carbohydrates (Isolyte Baxter 2,000 mL/day; glucose 50.0 g/L;Ringers lactate 1,000 mL/day) was used, and the patients were kept nil by mouth until the fourth postoperative day. The glucose levels were monitored during the first 72 hours. The study population was divided into normoglycemic and hyperglycemic patients according to the blood glucose level (<140 mg/dL and ≥140 mg/dL, respectively). The 2 groups were matched for age, sex, type of operative procedure, TNM status, and lymph node status. RESULTS: After matching, 104 patients were included for the analysis. Perioperative morbidity accounted for 18.3% with a greater rate for hyperglycemic patients (12% vs 31%; P = .018). When compared with normoglycemic patients, hyperglycemic patients had worse overall survival (45% vs 57%; P = .05) and worse disease-free survival (46% vs 68%; P = .02). On the multivariate analysis, hyperglycemia was an independent risk factor for a worse overall and disease-free survival. CONCLUSION: Postoperative hyperglycemia owing to surgical stress conditions can affect postoperative outcomes. Additionally, hyperglycemia may be a factor that promotes gastric cancer progression.

Bile Modulates Secretion of Incretins and Insulin: A Study of Human Extrahepatic Cholestasis.

OBJECTIVE: Changes in bile flow after bariatric surgery may beneficially modulate secretion of insulin and incretins, leading to diabetes remission. However, the exact mechanism(s) involved is still unclear. Here, we propose an alternative method to investigate the relationship between alterations in physiological bile flow and insulin and incretin secretion by studying changes in gut-pancreatic function in extrahepatic cholestasis in nondiabetic humans. METHODS: To pursue this aim, 58 nondiabetic patients with recent diagnosis of periampullary tumors underwent an oral glucose tolerance test (OGTT), and a subgroup of 16 patients also underwent 4-hour mixed meal tests and hyperinsulinemic-euglycemic clamps. RESULTS: The analysis of the entire cohort revealed a strong inverse correlation between total bilirubin levels and insulinogenic index. When subjects were divided on the basis of bilirubin levels, used as a marker of altered bile flow, subjects with high bilirubin levels displayed inferior glucose control and decreased insulin secretion during the OGTT. Altered bile flow elicited a markedly greater increase in glucagon and glucagon-like peptide 1 (GLP-1) secretion at fasting state, and following the meal, both glucagon and GLP-1 levels remained increased over time. Conversely, Glucose-dependent insulinotropic polypeptide (GIP) levels were comparable at the fasting state, whereas the increase following meal ingestion was significantly blunted with high bilirubin levels. We reveal strong correlations between total bilirubin and glucagon and GLP-1 levels. CONCLUSIONS: Our findings suggest that acute extrahepatic cholestasis determines major impairment in enteroendocrine gut-pancreatic secretory function. The altered bile flow may determine a direct deleterious effect on ß-cell function, perhaps mediated by the impairment of incretin hormone function.

Increased ß-Cell Workload Modulates Proinsulin-to-Insulin Ratio in Humans.

Increased proinsulin secretion, which characterizes type 2 diabetes and insulin resistance, may be due to an intrinsic, primitive defect in proinsulin processing or be secondary to increased demand on ß-cells (hyperinsulinemia secondary to insulin resistance). An alternative way to investigate the relation between relative hyperproinsulinemia and increased secretory demand is to study the dynamic changes in the proinsulin-to-insulin ratio after partial pancreatectomy, a model of acute increased ß-cell workload on the remaining pancreas. To pursue this aim, patients without diabetes, scheduled for partial pancreatectomy, underwent 4-h mixed-meal tests and hyperinsulinemic-euglycemic clamps before and after surgery. After acute ß-cell mass reduction, no changes were observed in the fasting proinsulin-to-insulin ratio, whereas the fold change in the proinsulin-to-insulin ratio significantly increased over time after the meal. Further, our data demonstrate that whole-body insulin resistance is associated with underlying defects in proinsulin secretion, which become detectable only in the presence of increased insulin secretion demand.

Nuclear Export of FoxO1 Is Associated with ERK Signaling in ß-Cells Lacking Insulin Receptors.

The insulin/insulin-like growth factor (IGF) signaling pathway plays a critical role in the regulation of islet cell biology. However, the signaling pathway(s) utilized by insulin to directly modulate ß-cells is unclear. To interrogate whether insulin exerts endocrine effects in regulating proteins in the insulin/IGF-1 signaling cascade in vivo in physiological states via the insulin receptor, we designed two experimental approaches: 1) glucose gavage and 2) hyperinsulinemic intravenous infusion, for studies in either ß-cell specific insulin receptor knock-out (ßIRKO) or control mice. Immunostaining of sections of pancreas (collected immediately after glucose gavage or insulin infusion) from controls showed significant increases in pAKT+, p-p70S6K+, and pERK+ ß-cells and a significant decrease in % nuclear FoxO1+ ß-cells compared with corresponding vehicle-treated groups. In contrast, in ßIRKOs, we observed no significant changes in pAKT+ or p-p70S6K+ ß-cells in either experiment; however, pERK+ ß-cells were significantly increased, and an attenuated decrease in % nuclear FoxO1+ ß cells was evident in response to glucose gavage or insulin infusion. Treatment of control and ßIRKO ß-cell lines with glucose or insulin showed significantly decreased % nuclear FoxO1+ ß-cells suggesting direct effects. Furthermore, blocking MAPK signaling had virtually no effect on FoxO1 nuclear export in controls, in contrast to attenuated export in ßIRKO ß-cells. These data suggest insulin acts on ß-cells in an endocrine manner in the normal situation; and that in ß-cells lacking insulin receptors, insulin and glucose minimally activate the Akt pathway, while ERK phosphorylation and FoxO1 nuclear export occur independently of insulin signaling.

Metabolic consequences of the occlusion of the main pancreatic duct with acrylic glue after pancreaticoduodenectomy.

BACKGROUND: Pancreaticoduodenectomy represents the major treatment for pancreatic and periampullary neoplasms. Complications related to pancreaticojejunostomy are still the leading cause of morbidity and mortality. A solution proposed by some surgeons is the occlusion of main pancreatic duct by acrylic glue, avoiding pancreaticojejunostomy. Nevertheless, the consequences of this procedure on glucose metabolism are not well-defined. METHODS: We retrospectively analyzed a cohort of 50 patients who underwent pancreaticoduodenectomy and had metabolic assessments available. The metabolic evaluation included the following: body composition and clinical evaluation, an oral glucose tolerance test, and an hyperinsulinemic euglycemic clamp procedure. RESULTS: Twenty-three patients underwent pancreatic duct occlusion and were compared with 27 patients, well-matched controls, who underwent pancreaticojejunostomy. Pancreatic duct occlusion leads to a greater impairment in insulin secretion compared with classic pancreaticojeunostomy. CONCLUSION: Pancreatic duct occlusion is associated with a greater reduction in insulin secretion but does not lead to meaningful differences in the management of patients with diabetes.

HCC development is associated to peripheral insulin resistance in a mouse model of NASH.

UNLABELLED: NAFLD is the most common liver disease worldwide but it is the potential evolution to NASH and eventually to hepatocellular carcinoma (HCC), even in the absence of cirrhosis, that makes NAFLD of such clinical importance. AIM: we aimed to create a mouse model reproducing the pathological spectrum of NAFLD and to investigate the role of possible co-factors in promoting HCC. METHODS: mice were treated with a choline-deficient L-amino-acid-defined-diet (CDAA) or its control (CSAA diet) and subjected to a low-dose i.p. injection of CCl4 or vehicle. Insulin resistance was measured by the euglycemic-hyperinsulinemic clamp method. Steatosis, fibrosis and HCC were evaluated by histological and molecular analysis. RESULTS: CDAA-treated mice showed peripheral insulin resistance at 1 month. At 1-3 months, extensive steatosis and fibrosis were observed in CDAA and CDAA+CCl4 groups. At 6 months, equal increase in steatosis and fibrosis was observed between the two groups, together with the appearance of tumor. At 9 months of treatment, the 100% of CDAA+CCl4 treated mice revealed tumor versus 40% of CDAA mice. Insulin-like Growth Factor-2 (IGF-2) and Osteopontin (SPP-1) were increased in CDAA mice versus CSAA. Furthermore, Immunostaining for p-AKT, p-c-Myc and Glypican-3 revealed increased positivity in the tumors. CONCLUSIONS: the CDAA model promotes the development of HCC from NAFLD-NASH in the presence of insulin resistance but in the absence of cirrhosis. Since this condition is increasingly recognized in humans, our study provides a model that may help understanding mechanisms of carcinogenesis in NAFLD.

A rare case of ectopic adrenocorticotropic hormone syndrome caused by a metastatic neuroendocrine tumor of the pancreas detected by 68Ga-DOTANOC and 18F-FDG PET/CT.

We report a rare case of ectopic adrenocorticotropic hormone (ACTH) syndrome caused by a metastatic neuroendocrine tumor (NET) of the pancreas detected by PET/CT using different tracers. A 43-year-old female patient with Cushing syndrome (CS) by suspected ectopic ACTH secretion underwent a 68Ga-DOTANOC and a 18F-FDG PET/CT. Both these functional imaging techniques revealed increased tracer uptake in a pancreatic mass and multiple liver metastases. Histology showed the presence of a mildly differentiated pancreatic NET. 68Ga-DOTANOC PET/CT may be a useful functional imaging method, complementary to 18F-FDG PET/CT, in detecting ACTH-secreting pancreatic NETs.

Removal of duodenum elicits GLP-1 secretion.

OBJECTIVE: To evaluate the effect of removal of the duodenum on the complex interplay between incretins, insulin, and glucagon in nondiabetic subjects. RESEARCH DESIGN AND METHODS: For evaluation of hormonal secretion and insulin sensitivity, 10 overweight patients without type 2 diabetes (age 61 ± 19.3 years and BMI 27.9 ± 5.3 kg/m(2)) underwent a mixed-meal test and a hyperinsulinemic-euglycemic clamp before and after pylorus-preserving pancreatoduodenectomy for ampulloma. RESULTS: All patients experienced a reduction in insulin (P = 0.002), C-peptide (P = 0.0002), and gastric inhibitory peptide (GIP) secretion (P = 0.0004), while both fasting and postprandial glucose levels increased (P = 0.0001); GLP-1 and glucagon responses to the mixed meal increased significantly after surgery (P = 0.02 and 0.031). While changes in GIP levels did not correlate with insulin, glucagon, and glucose levels, the increase in GLP-1 secretion was inversely related to the postsurgery decrease in insulin secretion (R(2) = 0.56; P = 0.012) but not to the increased glucagon secretion, which correlated inversely with the reduction of insulin (R(2) = 0.46; P = 0.03) and C-peptide (R(2) = 0.37; P = 0.04). Given that the remaining pancreas presumably has preserved intraislet anatomy, insulin secretory capacity, and α- and ß-cell interplay, our data suggest that the increased glucagon secretion is related to decreased systemic insulin. CONCLUSIONS: Pylorus-preserving pancreatoduodenectomy was associated with a decrease in GIP and a remarkable increase in GLP-1 levels, which was not translated into increased insulin secretion. Rather, the hypoinsulinemia may have caused an increase in glucagon secretion.