Adaptive infusion of a glucagon-like peptide-1/glucagon receptor co-agonist G3215, in adults with overweight or obesity: Results from a phase 1 randomized clinical trial.

AIMS: To determine whether a continuous infusion of a glucagon-like peptide receptor (GLP-1R)/glucagon receptor (GCGR) co-agonist, G3215 is safe and well tolerated in adults with overweight or obesity. METHODS: A phase 1 randomized, double blind, placebo-controlled trial of G3215 in overweight or obese participants, with or without type 2 diabetes. RESULTS: Twenty-six participants were recruited and randomized with 23 completing a 14-day subcutaneous infusion of G3215 or placebo. The most common adverse events were nausea or vomiting, which were mild in most cases and mitigated by real-time adjustment of drug infusion. There were no cardiovascular concerns with G3215 infusion. The pharmacokinetic characteristics were in keeping with a continuous infusion over 14 days. A least-squares mean body weight loss of 2.39 kg was achieved with a 14-day infusion of G3215, compared with 0.84 kg with placebo infusion (p < .05). A reduction in food consumption was also observed in participants receiving G3215 and there was no deterioration in glycaemia. An improved lipid profile was seen in G3215-treated participants and consistent with GCGR activation, a broad reduction in circulating amino acids was seen during the infusion period. CONCLUSION: An adaptive continuous infusion of the GLP-1/GCGR co-agonist, G3215, is safe and well tolerated offering a unique strategy to control drug exposure. By allowing rapid, response-directed titration, this strategy may allow for mitigation of adverse effects and afford significant weight loss within shorter time horizons than is presently possible with weekly GLP-1R and multi-agonists. These results support ongoing development of G3215 for the treatment of obesity and metabolic disease.

The postprandial secretion of peptide YY1-36 and 3-36 in obesity is differentially increased after gastric bypass versus sleeve gastrectomy.

OBJECTIVES: Peptide tyrosine tyrosine (PYY) exists as two species, PYY1-36 and PYY3-36 , with distinct effects on insulin secretion and appetite regulation. The detailed effects of bariatric surgery on PYY1-36 and PYY3-36 secretion are not known as previous studies have used nonspecific immunoassays to measure total PYY. Our objective was to characterize the effect of sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) on fasting and postprandial PYY1-36 and PYY3-36 secretion using a newly developed liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay. DESIGN AND SUBJECTS: Observational study in 10 healthy nonobese volunteers and 30 participants with obesity who underwent RYGB (n = 24) or SG (n = 6) at the Imperial Weight Centre [NCT01945840]. Participants were studied using a standardized mixed meal test (MMT) before and 1 year after surgery. The outcome measures were PYY1-36 and PYY3-36 concentrations. RESULTS: Presurgery, the fasting and postprandial levels of PYY1-36 and PYY3-36 were low, with minimal responses to the MMT, and these did not differ from healthy nonobese volunteers. The postprandial secretion of both PYY1-36 and PYY3-36 at 1 year was amplified after RYGB, but not SG, with the response being significantly higher in RYGB compared with SG. CONCLUSIONS: There appears to be no difference in PYY secretion between nonobese and obese volunteers at baseline. At 1 year after surgery, RYGB, but not SG, is associated with increased postprandial secretion of PYY1-36 and PYY3-36 , which may account for long-term differences in efficacy and adverse effects between the two types of surgery.

Sleeve gastrectomy causes weight-loss independent improvements in hepatic steatosis.

BACKGROUND AND AIMS: Sleeve gastrectomy (VSG) leads to improvement in hepatic steatosis, associated with weight loss. The aims of this study were to investigate whether VSG leads to weight-loss independent improvements in liver steatosis in mice with diet-induced obesity (DIO); and to metabolically and transcriptomically profile hepatic changes in mice undergoing VSG. METHODS: Mice with DIO were treated with VSG, sham surgery with subsequent food restriction to weight-match to the VSG group (Sham-WM), or sham surgery with return to unrestricted diet (Sham-Ad lib). Hepatic steatosis, glucose tolerance, insulin and glucagon resistance, and hepatic transcriptomics were investigated at the end of the study period and treatment groups were compared with mice undergoing sham surgery only (Sham-Ad lib). RESULTS: VSG led to much greater improvement in liver steatosis than Sham-WM (liver triglyceride mg/mg 2.5 ± 0.1, 2.1 ± 0.2, 1.6 ± 0.1 for Sham-AL, Sham-WM and VSG respectively; p = 0.003). Homeostatic model assessment of insulin resistance was improved following VSG only (51.2 ± 8.8, 36.3 ± 5.3, 22.3 ± 6.1 for Sham-AL, Sham-WM and VSG respectively; p = 0.03). The glucagon-alanine index, a measure of glucagon resistance, fell with VSG but was significantly increased in Sham-WM (9.8 ± 1.7, 25.8 ± 4.6 and 5.2 ± 1.2 in Sham Ad-lib, Sham-WM and VSG respectively; p = 0.0003). Genes downstream of glucagon receptor signalling which govern fatty acid synthesis (Acaca, Acacb, Me1, Acly, Fasn and Elovl6) were downregulated following VSG but upregulated in Sham-WM. CONCLUSIONS: Changes in glucagon sensitivity may contribute to weight-loss independent improvements in hepatic steatosis following VSG.

Differential effects of bile acids on the postprandial secretion of gut hormones: a randomized crossover study.

Bile acids (BA) regulate postprandial metabolism directly and indirectly by affecting the secretion of gut hormones like glucagon-like peptide-1 (GLP-1). The postprandial effects of BA on the secretion of other metabolically active hormones are not well understood. The objective of this study was to investigate the effects of oral ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) on postprandial secretion of GLP-1, oxyntomodulin (OXM), peptide YY (PYY), glucose-dependent insulinotropic peptide (GIP), glucagon, and ghrelin. Twelve healthy volunteers underwent a mixed meal test 60 min after ingestion of UDCA (12-16 mg/kg), CDCA (13-16 mg/kg), or no BA in a randomized crossover study. Glucose, insulin, GLP-1, OXM, PYY, GIP, glucagon, ghrelin, and fibroblast growth factor 19 were measured prior to BA administration at -60 and 0 min (just prior to mixed meal) and 15, 30, 60, 120, 180, and 240 min after the meal. UDCA and CDCA provoked differential gut hormone responses; UDCA did not have any significant effects, but CDCA provoked significant increases in GLP-1 and OXM and a profound reduction in GIP. CDCA increased fasting GLP-1 and OXM secretion in parallel with an increase in insulin. On the other hand, CDCA reduced postprandial secretion of GIP, with an associated reduction in postprandial insulin secretion. Exogenous CDCA can exert multiple salutary effects on the secretion of gut hormones; if these effects are confirmed in obesity and type 2 diabetes, CDCA may be a potential therapy for these conditions.NEW & NOTEWORTHY Oral CDCA and UDCA have different effects on gut and pancreatic hormone secretion. A single dose of CDCA increased fasting secretion of the hormones GLP-1 and OXM with an accompanying increase in insulin secretion. CDCA also reduced postprandial GIP secretion, which was associated with reduced insulin. In contrast, UDCA did not change gut hormone secretion fasting or postprandially. Oral CDCA could be beneficial to patients with obesity and diabetes.

Understanding the Treatment Algorithm of Patients with Metastatic Pancreatic Neuroendocrine Neoplasms: A Single-Institution Retrospective Analysis Comparing Outcomes of Chemotherapy, Molecular Targeted Therapy, and Peptide Receptor Radionuclide Therapy in 255 Patients.

BACKGROUND: The number of therapeutic options for patients with pancreatic neuroendocrine neoplasms (PNEN) has increased, but the optimal therapeutic algorithm has not been defined due to lack of randomised trials comparing different modalities. METHODS: We performed a retrospective study in patients with metastatic PNEN treated with ≥1 line of systemic therapy. The relationship between baseline characteristics, treatment type, and time to treatment failure (TTF), time to progression (TTP), and overall survival (OS) was analysed using the Kaplan-Meier method. Univariate and multivariate analyses were performed using the Cox proportional hazards model. RESULTS: Two hundred and fifty-five patients with metastatic PNEN had 491 evaluable lines of therapy. Independent predictors of TTF included treatment type, Ki-67, tumour grade, and chromogranin A. To reduce selection bias, a subgroup of 114 patients with grade 2 (G2) metastatic pancreatic neuroendocrine tumours (PNET) was analysed separately. These patients had received 234 lines of treatment (105 chemotherapy, 82 molecular targeted therapy, and 47 peptide receptor radionuclide therapy [PRRT]). In the G2 cohort, TTF and TTP were superior for PRRT compared with both chemotherapy and molecular targeted therapy. OS in the G2 cohort was also superior for those that had received PRRT compared with those that had not (median 84 vs. 56 months; HR 0.55, 95% CI: 0.31-0.98, p = 0.04). CONCLUSIONS: This study suggests that PRRT is associated with superior clinical outcomes relative to other systemic therapies for G2 metastatic PNET. Prospective studies are required to confirm these observations.

Safety and efficacy of an extended-release peptide YY analogue for obesity: A randomized, placebo-controlled, phase 1 trial.

AIM: To report the results from a Phase 1 trial of an extended-release peptide YY analogue, Y14, developed for the treatment of obesity. METHODS: Y14 was evaluated in overweight/obese volunteers in a Phase 1 randomized placebo-controlled trial, conducted in a clinical trial unit in the United Kingdom. Part A was a blinded single-ascending-dose study evaluating doses up to 36 mg. Part B was double-blinded and tested multiple ascending doses between 9 and 36 mg, given at 7- to 14-day intervals, over the course of 28 days, with up to five doses given per participant. The primary outcome was safety and tolerability; the secondary outcome was assessment of pharmacokinetic (PK) characteristics. Exploratory outcomes included food intake, body weight change and glucose tolerance after multiple doses. RESULTS: Between April 11, 2017 and December 24, 2018, 53 participants were enrolled into Part A and 24 into Part B of the trial. The PK characteristics were compatible with administration every 7 to 14 days. The most common adverse events (AEs) were nausea, vomiting or administration site reactions, which were mild in most cases and settled with time. No serious AE occurred. Participants given multiple doses of Y14 lost between -2.87 and -3.58 kg body weight compared with placebo (P <0.0001) at 31 days from the first dose, with profound reductions in food intake of 38% to 55% (P <0.0001, compared to placebo) and there was no evidence of tachyphylaxis. CONCLUSIONS: Our results support the continued development of Y14 as a novel treatment for obesity.

Peptide Receptor Radionuclide Therapy as a Novel Treatment for Metastatic and Invasive Phaeochromocytoma and Paraganglioma.

At present there is no clinical guideline or standardised protocol for the treatment of metastatic or invasive phaeochromocytoma and paraganglioma (collectively known as PPGL) due to the rarity of the disease and the lack of prospective studies or extended national databases. Prognosis is mainly determined by genetic predisposition, tumour burden, rate of disease progression, and location of metastases. For patients with progressive or symptomatic disease that is not amenable to surgery, there are various palliative treatment options available. These include localised therapies including radiotherapy, radiofrequency, or cryoablation, as well as liver-directed therapies for those patients with hepatic metastases (e.g., transarterial chemoembolisation) and systemic therapies including chemotherapy or molecular targeted therapies. There is currently intense research interest in the value of radionuclide therapy for neuroendocrine tumours, including phaeochromocytoma and paraganglioma, with either iodine-131 (131I)-radiolabelled metaiodobenzylguanidine or very recently peptide receptor radionuclide therapy (PRRT), and the most important contemporary clinical studies will be highlighted in this review. The studies to date suggest that PRRT may induce major clinical, biochemical, and radiological changes, with 177Lu-DOTATATE being most efficacious and presenting less toxicity than 90Y-DOTATATE. Newer combination therapies with combined radioisotopes, or combinations with chemotherapeutic agents, also look promising. Given the favourable efficacy, logistic, and safety profiles, we believe that PRRT will probably become the standard treatment for inoperable metastatic PPGL in the near future, but we await data from definitive randomised controlled trials to understand its role.

Cell-type-specific modulation of innate immune signalling by vitamin D in human mononuclear phagocytes.

Vitamin D is widely reported to inhibit innate immune signalling and dendritic cell (DC) maturation as a potential immunoregulatory mechanism. It is not known whether vitamin D has global or gene-specific effects on transcriptional responses downstream of innate immune stimulation, or whether vitamin D inhibition of innate immune signalling is common to different cells. We confirmed vitamin D inhibition of nuclear factor-κB (NF-κB) and p38 mitogen-activated protein kinase (MAPK) signalling in monocyte-derived DC (MDDC) stimulated with lipopolysaccharide (LPS). This was associated with global but modest attenuation of LPS-induced transcriptional changes at genome-wide level. Surprisingly, vitamin D did not inhibit innate immune NF-κB activation in monocyte-derived macrophages. Consistent with our findings in MDDC, ex vivo vitamin D treatment of primary peripheral blood myeloid DC also led to significant inhibition of LPS-inducible NF-κB activation. Unexpectedly, in the same samples, vitamin D enhanced activation of both NF-κB and MAPK signalling in primary peripheral blood monocytes. In a cross-sectional clinical cohort, we found no relationship between peripheral blood vitamin D levels and LPS-inducible activation of NF-κB and MAPK pathways in monocytes of myeloid DC. Remarkably, however, in vivo supplementation of people with vitamin D deficiency in this clinical cohort also enhanced LPS-inducible MAPK signalling in peripheral blood monocytes. Therefore, we report that vitamin D differentially modulates the molecular response to innate immune stimulation in monocytes, macrophages and dendritic cells. These results are of importance in the design of studies on vitamin D supplementation in infectious and immunological diseases.

Redefining the stress cortisol response to surgery.

BACKGROUND: Cortisol levels rise with the physiological stress of surgery. Previous studies have used older, less-specific assays, have not differentiated by severity or only studied procedures of a defined type. The aim of this study was to examine this phenomenon in surgeries of varying severity using a widely used cortisol immunoassay. METHODS: Euadrenal patients undergoing elective surgery were enrolled prospectively. Serum samples were taken at 8 am on surgical day, induction and 1 hour, 2 hour, 4 hour and 8 hour after. Subsequent samples were taken daily at 8 am until postoperative day 5 or hospital discharge. Total cortisol was measured using an Abbott Architect immunoassay, and cortisol-binding globulin (CBG) using a radioimmunoassay. Surgical severity was classified by POSSUM operative severity score. RESULTS: Ninety-three patients underwent surgery: Major/Major+ (n = 37), Moderate (n = 33) and Minor (n = 23). Peak cortisol positively correlated to severity: Major/Major+ median 680 [range 375-1452], Moderate 581 [270-1009] and Minor 574 [272-1066] nmol/L (Kruskal-Wallis test, P = .0031). CBG fell by 23%; the magnitude of the drop positively correlated to severity. CONCLUSIONS: The range in baseline and peak cortisol response to surgery is wide, and peak cortisol levels are lower than previously appreciated. Improvements in surgery, anaesthetic techniques and cortisol assays might explain our observed lower peak cortisols. The criteria for the dynamic testing of cortisol response may need to be reduced to take account of these factors. Our data also support a lower-dose, stratified approach to dosing of steroid replacement in hypoadrenal patients, to minimize the deleterious effects of over-replacement.

Peptide Receptor Radionuclide Treatment and (131)I-MIBG in the management of patients with metastatic/progressive phaeochromocytomas and paragangliomas.

BACKGROUND AND OBJECTIVES: Radionuclide therapy has been used to treat patients with progressive/metastatic paragangliomas (PGLs) and phaeochromocytomas (PCCs). The aim of the present study is to retrospectively compare the therapeutic outcomes of these modalities in patients with progressive/metastatic PCCs and PGLs. METHODS: Patients with progressive/metastatic PGLs and PCCs that were subjected to radionuclide treatment in our department were retrieved from our department's database for the period 1998-2013. Overall survival (OS), progression free survival (PFS), event free survival (EFS), and response to treatment were calculated. Treatment toxicity was documented. RESULTS: Twenty-two patients with progressive/metastatic PGLs or PCCs were treated with either (131)I-MIBG, (90)Y-DOTATATE or (177)Lu-DOTATATE. A total of 30 treatments were administered (16 treatments with (131)I-MIBG, 2 with (177)Lu-DOTATATE, and 12 with (90)Y-DOTATATE. Patients treated with PRRT had increased PFS and response to treatment compared to (131)I-MIBG treated patients (P < 0.05). However, difference in OS was non significant (P = 0.09). There was no difference in major toxicities between groups. When comparing only patients with PGLs, OS, PFS, EFS, and response to treatment were significantly higher in the PRRT treatment group. CONCLUSION: PRRT treatment offers increased OS, PFS, EFS, and response to treatment compared to (131)I-MIBG therapy in patients with progressive/malignant PGLs.

Real-life experience of tolvaptan use in the treatment of severe hyponatraemia due to syndrome of inappropriate antidiuretic hormone secretion.

OBJECTIVE: European guidelines do not recommend tolvaptan for treatment of syndrome of inappropriate antidiuretic hormone secretion (SIADH), principally owing to concerns about risk of overly rapid correction of hyponatraemia. This study evaluated the real-life effectiveness and safety of tolvaptan. DESIGN: Consecutive case series. PATIENTS: Inpatients treated with tolvaptan for SIADH in 2 UK hospitals over a 3-year period. MEASUREMENTS: The primary outcome measures were serum sodium (sNa) correction at 24 and 48 h after tolvaptan therapy. RESULTS: This case series included 61 patients aged 74·4 ± 15·3 years with (mean ± SD) sNa 119·9 ± 5·5 mmol/l. The mean sNa increase 24 h after tolvaptan initiation was 9 ± 3·9 mmol/l. Excessive correction of hyponatraemia was observed in 23% of patients with all these patients having baseline sNa <125 mmol/l, but no cases of osmotic demyelination syndrome were recorded. At the end of tolvaptan therapy, sNa increase was 13·5 ± 5·9 mmol/l with 96·7% of patients having sNa increase ≥5 mmol/l in 48 h. There was a negative significant correlation (P = 0·012) between baseline sNa and 24-h change; for every 1 mmol/l reduction in baseline value, sNa increased by an additional 0·23 mmol/l (95% CI 0·05-0·41). CONCLUSIONS: Tolvaptan is effective in correcting hyponatraemia. Without rigorous electrolyte monitoring, tolvaptan carries a significant risk of overly rapid sodium correction, especially in patients with starting sNa <125 mmol/l. Tolvaptan should be used with great caution under close electrolyte monitoring.

Regulation of CYP27B1 and CYP24A1 hydroxylases limits cell-autonomous activation of vitamin D in dendritic cells.

The active vitamin D metabolite 1α,25-dihydroxyvitamin D (1,25[OH]2 D) potently inhibits DC priming of T-cell activation, suggesting that it mediates a homeostatic role in this context. Therefore, careful regulation of 1,25[OH]2 D levels is necessary to avoid inappropriate inhibition of T-cell activation. Cell-autonomous control of vitamin D activity can be modulated by the action of the vitamin D-activating and -inactivating hydroxylases, CYP27B1, and CYP24A1, respectively. We show that in comparison to macrophages, human monocyte-derived DCs exhibit significantly less activation of 25-dihydroxyvitamin D to 1,25[OH]2 D, and that DCs predominantly express a truncated CYP27B1 transcript that may contribute to the deficiency in activation of vitamin D. Furthermore, in response to stimulation with 1,25[OH]2 D, upregulation of the inactivating enzyme CYP24A1 curtailed the functional effects of vitamin D in DCs, but not macrophages. Production of 1,25[OH]2 D by macrophages was adequate to induce expression of vitamin D-responsive genes by DCs, inhibit DC maturation in response to innate immune stimulation and DC-dependent T-cell responses. Our data suggest that in comparison to macrophages, differential regulation of hydroxylases limits autocrine vitamin D activity in DCs, and that paracrine activation of vitamin D exerts a more potent mechanism for homeostatic control of DC function.

Phaeochromocytomas and paragangliomas: A difference in disease behaviour and clinical outcomes.

BACKGROUND: Phaeochromocytomas and paragangliomas arise from the same chromaffin cell, but evidence suggests they do not represent a single clinical entity. The aim of this study was to compare clinical presentations, outcomes of surgical and oncological treatments and survival in patients with phaeochromocytomas and paragangliomas. METHODS: A retrospective review was undertaken of all patients treated for these conditions at our centre between 1983 and 2012. RESULTS: One hundred and six patients (88 adults, 18 children) with phaeochromocytoma (n = 83) or paraganglioma (n = 23) were studied. Catecholamine symptoms and incidentalomas were the main presentations in phaeochromocytoma patients (67% and 17%) respectively, but in those with paragangliomas pain (39%) was more common (P < 0.001). More paragangliomas were malignant (14/23 vs 9/83, P < 0.0001), larger (9.17 ± 4.95 cm vs. 5.8 ± 3.44 cm, P = 0.001) and had a higher rate of conversion to open surgery (P = <0.01), more R2 resections, more postoperative complications and a longer hospital stay (P = 0.014). MIBG uptake in malignant paragangliomas was lower than in malignant phaeochromocytomas (36% vs. 100%, P = 0.002) and disease stabilisation was achieved in 29% and 86% of patients respectively. (90) Y-DOTA-octreotate had a 78% response rate in malignant paragangliomas. CONCLUSION: The clinical differences between paragangliomas and phaeochromocytomas support the view that they should be considered as separate clinical entities.

Exon skipping of hepatic APOB pre-mRNA with splice-switching oligonucleotides reduces LDL cholesterol in vivo.

Familial hypercholesterolemia (FH) is a genetic disorder characterized by extremely high levels of plasma low-density lipoprotein (LDL), due to defective LDL receptor-apolipoprotein B (APOB) binding. Current therapies such as statins or LDL apheresis for homozygous FH are insufficiently efficacious at lowering LDL cholesterol or are expensive. Treatments that target APOB100, the structural protein of LDL particles, are potential therapies for FH. We have developed a series of APOB-directed splice-switching oligonucleotides (SSOs) that cause the expression of APOB87, a truncated isoform of APOB100. APOB87, like similarly truncated isoforms expressed in patients with a different condition, familial hypobetalipoproteinemia, lowers LDL cholesterol by inhibiting very low-density lipoprotein (VLDL) assembly and increasing LDL clearance. We demonstrate that these "APO-skip " SSOs induce high levels of exon skipping and expression of the APOB87 isoform, but do not substantially inhibit APOB48 expression in cell lines. A single injection of an optimized APO-skip SSO into mice transgenic for human APOB resulted in abundant exon skipping that persists for >6 days. Weekly treatments generated a sustained reduction in LDL cholesterol levels of 34-51% in these mice, superior to pravastatin in a head-to-head comparison. These results validate APO-skip SSOs as a candidate therapy for FH.

Multicentre study of investigation and management of inpatient hyponatraemia in the UK.

PURPOSE: Hyponatraemia is associated with significant morbidity and mortality. The objectives of this study were to evaluate the investigation and management of hyponatraemia and to assess the use of different therapeutic modalities and their effectiveness in routine practice. STUDY DESIGN: This multicentre, retrospective, observational study was conducted at three acute NHS Trusts in March 2013. A retrospective chart review was performed on the first 100 inpatients with serum sodium (sNa) ≤128 mmol/L during hospitalisation. RESULTS: One hundred patients (47 male, 53 female) with a mean±SD age of 71.3±15.4 years and nadir sNa of 123.4±4.3 mmol/L were included. Only 23/100 (23%) had measurements of paired serum and urine osmolality and sodium, while 31% had an assessment of adrenal reserve. The aetiology of hyponatraemia was unrecorded in 58% of cases. The mean length of hospital stay was 17.5 days with an inpatient mortality rate of 16%. At hospital discharge, 53/84 (63.1%) patients had persistent hyponatraemia, including 20/84 (23.8%) with sNa <130 mmol/L. Overall 37/100 (37%) patients did not have any treatment for hyponatraemia. Among 76 therapeutic episodes, the most commonly used treatment modalities were isotonic saline in 38/76 cases (50%) and fluid restriction in 16/76 (21.1%). Fluid restriction failed to increase sNa by >1 mmol/L/day in 8/10 (80%) cases compared with 4/26 (15.4%) for isotonic saline. CONCLUSIONS: Underinvestigation and undertreatment of hyponatraemia is a common occurrence in UK clinical practice. Therefore, development of UK guidelines and introduction of electronic alerts for hyponatraemia should be considered to improve clinical practice.