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Introduction: Second-generation basal insulin analogues have been shown to reduce hypoglycemia in several trials and observational studies of select populations; however, it remains unclear whether these results persist in real-world settings. Using self-reported hypoglycemia events, we assessed whether second-generation basal insulin analogues reduce rates of hypoglycemia events (non-severe/severe; overall/daytime/nocturnal) compared to earlier intermediate/basal insulin analogues among people with insulin-treated type 1 or 2 diabetes. Methods: We used prospectively collected data from the Investigating Novel Predictions of Hypoglycemia Occurrence Using Real-World Models (iNPHORM) panel survey. This US-wide, 1-year internet-based survey assessed hypoglycemia experiences and related sociodemographic and clinical characteristics of people with diabetes (February 2020−March 2021). We estimated population-average rate ratios for hypoglycemia comparing second-generation to earlier intermediate/basal insulin analogues using negative binomial regression, adjusting for confounders. Within-person variability of repeated observations was addressed with generalized estimating equations. Results: Among iNPHORM participants with complete data, N = 413 used an intermediate/basal insulin analogue for ≥ 1 month during follow-up. After adjusting for baseline and time-updated confounders, average second-generation basal insulin analogue users experienced a 19% (95% CI 3–32%, p = 0.02) lower rate of overall non-severe hypoglycemia and 43% (95% CI 26–56%, p < 0.001) a lower rate of nocturnal non-severe hypoglycemia compared to earlier intermediate/basal insulin users. Overall severe hypoglycemia rates were similar among second-generation and earlier intermediate/basal insulin users (p = 0.35); however, the rate of severe nocturnal hypoglycemia was reduced by 44% (95% CI 10–65%, p = 0.02) among second-generation insulin users compared to earlier intermediate/basal insulin users. Conclusion: Our real-world results suggest second-generation basal insulin analogues reduce rates of hypoglycemia, especially nocturnal non-severe and severe events. Whenever possible and feasible, clinicians should prioritize prescribing these agents over first-generation basal or intermediate insulin in people with type 1 and 2 diabetes. [ABSTRACT FROM AUTHOR]

Preptin is derived from the cleavage of the E‐peptide of pro‐insulin‐like growth factor (IGF)‐II and is an insulin secretagogue. Observational studies have linked elevated circulating preptin to metabolic dysfunction in humans; however, a causal role for preptin in metabolic dysfunction has not been established. Additionally, preptin can promote osteoblast proliferation and differentiation, suggesting a link with skeletal health. We previously described a global preptin knockout (KO) model. In this study, we sought to uncover the impact of preptin KO in mice on the response to a moderately high‐fat diet (HFD) and low‐fat diet (LFD). HFD groups had higher weight and fat mass gain, lower trabecular and cortical bone volume and fracture load, and higher liver triglycerides. In males, preptin deficiency led to lower blood glucose than wild‐type (WT) mice under LFD conditions. This was accompanied by differences in bone microarchitecture, including lower trabecular bone volume fraction, trabecular number, and lower cortical thickness. These differences were absent in female mice, although KO females had a HFD‐driven increase in fat mass and liver triglycerides that was absent in WT mice. Female WT mice had increased glucose‐stimulated insulin secretion under HFD conditions that was absent in female KO mice. Overall, preptin may have a detrimental impact on metabolism and a positive impact on bone health in male mice and may protect against liver fat storage in females while enabling islet compensation under HFD conditions. When we consider that serum preptin levels are elevated in humans of both sexes in pathological states in which insulin levels are elevated, the impact of preptin on comorbidity risk needs to be better understood. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

ABSTRACT Preptin is derived from the cleavage of the E‐peptide of pro‐insulin‐like growth factor (IGF)‐II and is an insulin secretagogue. Observational studies have linked elevated circulating preptin to metabolic dysfunction in humans; however, a causal role for preptin in metabolic dysfunction has not been established. Additionally, preptin can promote osteoblast proliferation and differentiation, suggesting a link with skeletal health. We previously described a global preptin knockout (KO) model. In this study, we sought to uncover the impact of preptin KO in mice on the response to a moderately high‐fat diet (HFD) and low‐fat diet (LFD). HFD groups had higher weight and fat mass gain, lower trabecular and cortical bone volume and fracture load, and higher liver triglycerides. In males, preptin deficiency led to lower blood glucose than wild‐type (WT) mice under LFD conditions. This was accompanied by differences in bone microarchitecture, including lower trabecular bone volume fraction, trabecular number, and lower cortical thickness. These differences were absent in female mice, although KO females had a HFD‐driven increase in fat mass and liver triglycerides that was absent in WT mice. Female WT mice had increased glucose‐stimulated insulin secretion under HFD conditions that was absent in female KO mice. Overall, preptin may have a detrimental impact on metabolism and a positive impact on bone health in male mice and may protect against liver fat storage in females while enabling islet compensation under HFD conditions. When we consider that serum preptin levels are elevated in humans of both sexes in pathological states in which insulin levels are elevated, the impact of preptin on comorbidity risk needs to be better understood. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Preptin is a 34-amino acid peptide derived from the E-peptide of pro-insulin-like growth factor 2 and is co-secreted with insulin from β-cells. Little is understood about the effects of endogenous preptin on whole body glucose metabolism. We developed a novel mouse model in which the preptin portion of Igf2 was genetically ablated in all tissues, hereafter referred to as preptin knockout (KO), and tested the hypothesis that the removal of preptin will lead to a decreased insulin response to a metabolic challenge. Preptin KO and wild-type (WT) mice underwent weekly fasting blood glucose measurements, intraperitoneal insulin tolerance tests (ITT) at 9, 29, and 44 wk of age, and an oral glucose tolerance test (GTT) at 45 wk of age. Preptin KO mice of both sexes had similar Igf2 exon 2-3 mRNA expression in the liver and kidney compared with WT mice, but Igf2 exon 3-4 (preptin) expression was not detectable. Western blot analysis of neonatal serum indicated that processing of pro-IGF2 translated from the KO allele may be altered. Preptin KO mice had similar body weight, body composition, β-cell area, and fasted glucose concentrations compared with WT mice in both sexes up to 47 wk of age. Female KO mice had a diminished ability to mount an insulin response following glucose stimulation in vivo. This effect was absent in male KO mice. Although preptin is not essential for glucose homeostasis, when combined with previous in vitro and ex vivo findings, these data show that preptin positively impacts β-cell function. [ABSTRACT FROM AUTHOR]

Rapid increases in cell volume reduce the size of the extracellular space (ECS) and are associated with elevated brain tissue excitability. We recently demonstrated that astrocytes, but not neurons, rapidly swell in elevated extracellular potassium (^[K+]o) up to 26 mM. However, effects of acute astrocyte volume fluctuations on neuronal excitability in ^[K+]o have been difficult to evaluate due to direct effects on neuronal membrane potential and generation of action potentials. Here we set out to isolate volume-specific effects occurring in ^[K+]o on CA1 pyramidal neurons in acute hippocampal slices by manipulating cell volume while recording neuronal glutamate currents in 10.5 mM [K+]o + tetrodotoxin (TTX) to prevent neuronal firing. Elevating [K+]o to 10.5 mM induced astrocyte swelling and produced significant increases in neuronal excitability in the form of mixed a-amino-3-hydroxy-5-methyl-4- isoxazolepropionic acid (AMPA)/N-methyl-D-aspartate (NMDA) receptor mEPSCs and NMDA receptor-dependent slow inward currents (SICs). Application of hyperosmolar artificial cerebrospinal fluid (ACSF) by addition of mannitol in the continued presence of 10.5 mM K+ forced shrinking of astrocytes and to a lesser extent neurons, which resisted swelling in ^[K+]o. Cell shrinking and dilation of the ECS significantly dampened neuronal excitability in 10.5 mM K+. Subsequent removal of mannitol amplified effects on neuronal excitability and nearly doubled the volume increase in astrocytes, presumably due to continued glial uptake of K+ while mannitol was present. Slower, larger amplitude events mainly driven by NMDA receptors were abolished by mannitol-induced expansion of the ECS. Collectively, our findings suggest that cell volume regulation of the ECS in elevated [K+]o is driven predominantly by astrocytes, and that cell volume effects on neuronal excitability can be effectively isolated in elevated [K+]o conditions. [ABSTRACT FROM AUTHOR]

Rapid increases in cell volume reduce the size of the extracellular space (ECS) and are associated with elevated brain tissue excitability. We recently demonstrated that astrocytes, but not neurons, rapidly swell in elevated extracellular potassium (∧[K+]o) up to 26 mM. However, effects of acute astrocyte volume fluctuations on neuronal excitability in ∧[K+]o have been difficult to evaluate due to direct effects on neuronal membrane potential and generation of action potentials. Here we set out to isolate volume-specific effects occurring in ∧[K+]o on CA1 pyramidal neurons in acute hippocampal slices by manipulating cell volume while recording neuronal glutamate currents in 10.5 mM [K+]o + tetrodotoxin (TTX) to prevent neuronal firing. Elevating [K+]o to 10.5 mM induced astrocyte swelling and produced significant increases in neuronal excitability in the form of mixed α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/N-methyl-D-aspartate (NMDA) receptor mEPSCs and NMDA receptor-dependent slow inward currents (SICs). Application of hyperosmolar artificial cerebrospinal fluid (ACSF) by addition of mannitol in the continued presence of 10.5 mM K+ forced shrinking of astrocytes and to a lesser extent neurons, which resisted swelling in ∧[K+]o. Cell shrinking and dilation of the ECS significantly dampened neuronal excitability in 10.5 mM K+. Subsequent removal of mannitol amplified effects on neuronal excitability and nearly doubled the volume increase in astrocytes, presumably due to continued glial uptake of K+ while mannitol was present. Slower, larger amplitude events mainly driven by NMDA receptors were abolished by mannitol-induced expansion of the ECS. Collectively, our findings suggest that cell volume regulation of the ECS in elevated [K+]o is driven predominantly by astrocytes, and that cell volume effects on neuronal excitability can be effectively isolated in elevated [K+]o conditions.

Background: Hypoglycemia prognostic models contingent on prospective, self-reported survey data offer a powerful avenue for determining real-world event susceptibility and interventional targets. Objective: This protocol describes the design and implementation of the 1-year iNPHORM (Investigating Novel Predictions of Hypoglycemia Occurrence Using Real-world Models) study, which aims to measure real-world self-reported severe and nonsevere hypoglycemia incidence (daytime and nocturnal) in American adults with type 1 or 2 diabetes mellitus prescribed insulin and/or secretagogues, and develop and internally validate prognostic models for severe, nonsevere daytime, and nonsevere nocturnal hypoglycemia. As a secondary objective, iNPHORM aims to quantify the effects of different antihyperglycemics on hypoglycemia rates. Methods: iNPHORM is a prospective, 12-wave internet-based panel survey that was conducted across the United States. Americans (aged 18-90 years) with self-reported type 1 or 2 diabetes mellitus prescribed insulin and/or secretagogues were conveniently sampled via the web from a pre-existing, closed, probability-based internet panel (sample frame). A sample size of 521 baseline responders was calculated for this study. Prospective data on hypoglycemia and potential prognostic factors were self-assessed across 14 closed, fully automated questionnaires (screening, baseline, and 12 monthly follow-ups) that were piloted using semistructured interviews (n=3) before fielding; no face-to-face contact was required as part of the data collection. Participant responses will be analyzed using multivariable count regression and machine learning techniques to develop and internally validate prognostic models for 1-year severe and 30-day nonsevere daytime and nocturnal hypoglycemia. The causal effects of different antihyperglycemics on hypoglycemia rates will also be investigated. Results: Recruitment and data collection occurred between February 2020 and March 2021 (ethics approval was obtained on December 17, 2019). A total of 1694 participants completed the baseline questionnaire, of whom 1206 (71.19%) were followed up for 12 months. Most follow-up waves (10,470/14,472, 72.35%) were completed, translating to a participation rate of 179% relative to our target sample size. Over 70.98% (856/1206) completed wave 12. Analyses of sample characteristics, quality metrics, and hypoglycemia incidence and prognostication are currently underway with published results anticipated by fall 2022. Conclusions: iNPHORM is the first hypoglycemia prognostic study in the United States to leverage prospective, longitudinal self-reports. The results will contribute to improved real-world hypoglycemia risk estimation and potentially safer, more effective clinical diabetes management. [ABSTRACT FROM AUTHOR]

Background. Fibroblast growth factor 21 (FGF21) treatment improves metabolic homeostasis in diverse species, including humans. Physiologically, plasma FGF21 levels increase modestly after glucose ingestion, but it is unclear whether this is mediated by glucose itself or due to a secondary effect of postprandial endocrine responses. A refined understanding of the mechanisms that control FGF21 release in humans may accelerate the development of small-molecule FGF21 secretagogues to treat metabolic disease. This study aimed to determine whether FGF21 secretion is stimulated by elevations in plasma glucose, insulin, or glucagon-like peptide-1 (GLP-1) in humans. Methods. Three groups of ten healthy participants were included in a parallel-group observational study. GroupAunderwent a hyperglycemic infusion; Group B underwent a 40 mU/m2/min hyperinsulinemic euglycemic clamp; Group C underwent two pancreatic clamps (to suppress endogenous insulin secretion) with euglycemic and hyperglycemic stages with an infusion of either saline or 0.5 pmol/kg/min GLP-1. Plasma FGF21 concentrations were measured at baseline and during each clamp stage by ELISA. Results. Plasma FGF21 was unaltered during hyperglycemic infusion and hyperinsulinemic euglycemic clamps, compared to baseline. FGF21 was, however, increased by hyperglycemia under pancreatic clamp conditions (P < 0:05), while GLP-1 infusion under pancreatic clamp conditions did not change circulating FGF21 levels. Conclusion. Increases in plasma FGF21 are likely driven directly by changes in plasma glucose independent of changes in insulin or GLP-1 secretion. Ecologically valid postprandial investigations are now needed to confirm our observations from basic science infusion models. [ABSTRACT FROM AUTHOR]

Background Fibroblast growth factor 21 (FGF21) treatment improves metabolic homeostasis in diverse species, including humans. Physiologically, plasma FGF21 levels increase modestly after glucose ingestion, but it is unclear whether this is mediated by glucose itself or due to a secondary effect of postprandial endocrine responses. A refined understanding of the mechanisms that control FGF21 release in humans may accelerate the development of small-molecule FGF21 secretagogues to treat metabolic disease. This study aimed to determine whether FGF21 secretion is stimulated by elevations in plasma glucose, insulin, or glucagon-like peptide-1 (GLP-1) in humans. Methods Three groups of ten healthy participants were included in a parallel-group observational study. Group A underwent a hyperglycemic infusion; Group B underwent a 40 mU/m2/min hyperinsulinemic euglycemic clamp; Group C underwent two pancreatic clamps (to suppress endogenous insulin secretion) with euglycemic and hyperglycemic stages with an infusion of either saline or 0.5 pmol/kg/min GLP-1. Plasma FGF21 concentrations were measured at baseline and during each clamp stage by ELISA. Results Plasma FGF21 was unaltered during hyperglycemic infusion and hyperinsulinemic euglycemic clamps, compared to baseline. FGF21 was, however, increased by hyperglycemia under pancreatic clamp conditions (P

Background: Bisacodyl is a member of the diphenylmethane family and is considered to be a stimulant laxative. It has a dual prokinetic and secretory action and needs to be converted into the active metabolite bis‐(p‐hydroxyphenyl)‐pyridyl‐2‐methane (BHPM) in the gut to achieve the desired laxative effect. Bisacodyl acts locally in the large bowel by directly enhancing the motility, reducing transit time, and increasing the water content of the stool. A recent network meta‐analysis concluded that bisacodyl showed similar efficacy to prucalopride, lubiprostone, linaclotide, tegaserod, velusetrag, elobixibat, and sodium picosulfate for the primary endpoint of ≥3 complete spontaneous bowel movements (CSBM)/week and an increase of ≥1 CSBM/week over baseline. The meta‐analysis also found that bisacodyl may be superior to the other laxatives for the secondary endpoint of change from baseline in the number of spontaneous bowel movements per week in patients with chronic constipation. This observation stimulated the authors to review the available literature on bisacodyl, which has been available on the market since the 1950 s. Purpose: The aim of the current review was to provide an overview of the historic background, structure, function, and mechanism of action of bisacodyl. Additionally, we discuss the important features and studies for bisacodyl to understand its peculiar characteristics and guide its use in clinical practice, but also stimulate research on open questions. [ABSTRACT FROM AUTHOR]

We adapted a radioligand receptor binding assay for measuring insulin levels in unknown samples. The assay enables rapid and accurate determination of insulin concentrations in experimental samples, such as from insulin-secreting cells. The principle of the method is based on the binding competition of insulin in a measured sample with a radiolabeled insulin for insulin receptor (IR) in IM-9 cells. Both key components, radiolabeled insulin and IM-9 cells, are commercially available. The IR binding assay was used to determine unknown amounts of insulin secreted by MIN6 β cell line after stimulation with glucose, arginine, ornithine, dopamine, and serotonin. The experimental data obtained by the IR binding assay were compared to the results determined by RIA kits and both methods showed a very good agreement of results. We observed the stimulation of glucose-induced insulin secretion from MIN6 cells by arginine, weaker stimulation by ornithine, but inhibitory effects of dopamine. Serotonin effects were either stimulatory or inhibitory, depending on the concentration of serotonin used. The results will require further investigation. The study also clearly revealed advantages of the IR binding assay that allows the measuring of a higher throughput of measured samples, with a broader range of concentrations than in the case of RIA kits. The IR binding assay can provide an alternative to standard RIA and ELISA assays for the determination of insulin levels in experimental samples and can be especially useful in scientific laboratories studying insulin production and secretion by β cells and searching for new modulators of insulin secretion. [ABSTRACT FROM AUTHOR]

Phenotypic screening is a neoclassical approach for drug discovery. We conducted phenotypic screening for insulin secretion enhancing agents using INS-1E insulinoma cells as a model system for pancreatic beta-cells. A principal regulator of insulin secretion in beta-cells is the metabolically regulated potassium channel Kir6.2/SUR1 complex. To characterize hit compounds, we developed an assay to quantify endogenous potassium channel activity in INS-1E cells. We quantified ligand-regulated potassium channel activity in INS-1E cells using fluorescence imaging and thallium flux. Potassium channel activity was metabolically regulated and coupled to insulin secretion. The pharmacology of channel opening agents (diazoxide) and closing agents (sulfonylureas) was used to validate the applicability of the assay. A precise high-throughput assay was enabled, and phenotypic screening hits were triaged to enable a higher likelihood of discovering chemical matter with novel and useful mechanisms of action. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of 0.2% ambroxol eye drop on tear secretion and corneal healing on a rabbit dry eye model, and to delineate potential underlying mechanisms. Materials and method: A mixed mechanism dry eye model was created using 12 healthy New Zealand rabbits by excision of the main lacrimal glands, Harderian gland and nictitating membrane. Establishment of the model was confirmed by the decrease of Schirmer I and increase of corneal fluorescein staining scores. Two weeks after model creation, the rabbits were randomly and evenly divided into NaCl, 0.1% sodium hyaluronate and 0.2% ambroxol groups. Each group was administered the respective eye drops 4 times a day for four weeks. The Schirmer I test and corneal fluorescein staining were performed at two and four weeks. After four weeks of treatment, the animals were sacrificed and the conjunctiva and eyelid specimens collected. Inflammatory factors IL-8, TNF-α, and goblet cell specific mucin MUC5AC were measured by ELISA while the lid meibomian gland was evaluated by oil red O staining. Results: Compared with the baseline, 2 weeks after the surgery, Schirmer I test value decreased significantly (20.35 ± 5.18 mm/5 min vs 13.95 ± 4.64 mm/5 min, p < 0.01), and the fluorescein staining score increased significantly (0.5 ± 0.6 vs 5.5 ± 1.4, p < 0.01). After four weeks of treatment, compared with the NaCl and sodium hyaluronate groups, tear secretion in ambroxol group increased significantly (p < 0.01), while the corneal fluorescence staining score decreased significantly (p < 0.01). In the conjunctival tissue, significant decrease was seen in TNF-α (p < 0.01) and IL-8 [p (unilateral) < 0.05] concentrations in ambroxol group, and significant increase in MUC5AC concentration (p < 0.01) in ambroxol group as well. The lipid content in the lid meibomian glands appeared increased after the administration of ambroxol. Conclusion: The present rabbit dry eye model study demonstrated potentials of topically administered 0.2% ambroxol in stimulating tear and mucin secretion, inhibiting ocular surface inflammation, promoting corneal healing, and possibly augmenting meibomian gland lipid production.

(1) Background: Artemia salina is a brine shrimp containing high concentrations of dinucleotides, molecules with properties for dry eye treatment. For this reason, the purpose of the study was to evaluate the effect of the artificial tears based on an extract of Artemia salina in a rabbit dry eye model. (2) Methods: A prospective and randomized study was carried out. Twenty rabbits were divided into 4 groups (n = 5, each group): healthy rabbits, dry eye rabbits, dry eye rabbits treated with hypromellose (HPMC), and dry eye rabbits treated with Artemia salina. Dry eye was induced by the topical instillation of 0.2% benzalkonium chloride. The measurements were performed before and after the treatment for 5 consecutive days. (3) Results: The topical instillation of artificial tears containing Artemia salina showed beneficial effects on tear secretion, tear break-up time, corneal staining, the density of Goblet cells, heigh of mucin cloud secreted by these cells, and mRNA levels of IL-1β and MMP9 in conjunctival cells. Compared with the HPMC, there was a statistically significant improvement (p < 0.05) with the Artemia salina in all the variables under study, except for the conjunctival hyperemia, density of Goblet cells, and mRNA levels of IL-6. (4) Conclusions: The potential of artificial tears based on Artemia salina as a secretagogue agent for dry eye treatment was confirmed, opening the door for future clinical trials and studies to extrapolate the findings for dry eye patients.

Introduction: The objective of this study was to establish the burden of hypoglycemia on family members of people with diabetes (PWDs) and to gain an understanding of how conversations about hypoglycemia can contribute to diabetes care. Methods: This was a multinational cross-sectional study of family members of people with type 1 or type 2 diabetes taking insulin and/or secretagogues for ≥ 12 months who voluntarily completed an online questionnaire. Results: Overall, 4300 family members of PWDs (type 1 [29%], type 2 [46%], unknown [25%]) were surveyed. Two in three family members (66%) reported thinking about the hypoglycemia of the PWD at least monthly, and 64% felt worried or anxious about the PWD's risk for hypoglycemia. There was general agreement among family members that more conversations about hypoglycemia would have a positive impact on the PWD's life (76%). Conclusions: Hypoglycemia can present a burden on the lives of family members of PWDs. Conversations about hypoglycemia, facilitated by a healthcare professional, may reduce this burden and hypoglycemia risk. Funding: Novo Nordisk A/S. [ABSTRACT FROM AUTHOR]

Stimulation of insulin production by insulin secretagogue use may impact T helper cells’ cytokine production. This dataset presents the relationship between baseline insulin secretagogues use in women diagnosed with breast cancer and type 2 diabetes mellitus, the T-helper 1 and 2 produced cytokine profiles at the time of breast cancer diagnosis, and subsequent cancer outcomes. A Pearson correlation analysis evaluating the relationship between T-helper cytokines stratified by of insulin secretagogues use and controls is also provided.

Monocytes’ infiltration into the tumor tissue and their activation to tumor-associated macrophages is an essential step in tumor development, also playing a critical role in an eventual metastasis. Stimulation of endogenous insulin production by oral insulin secretagogue treatment has the potential to interfere with the production and release of C–C chemokines, a group of potent inflammatory cytokines acting as monocyte chemo-attractants and influencing their behavior in the tumor microenvironment. Studied plasma samples were collected under a previously reported study design involving a population of women diagnosed with breast cancer presenting with or without type 2 diabetes mellitus at the time of breast cancer diagnosis (Wintrob et al., 2017, 2016) [1,2]. The data presented here shows the relationship between pre-existing use of insulin secretagogue, the inflammatory C–C chemokine profiles at the time of breast cancer diagnosis, and subsequent cancer outcomes. A Pearson correlation analysis stratified by secretagogue use and controls was implemented to evaluate the relationship between the investigated biomarkers and respectively each of these biomarkers and the other relevant reported cytokine datasets derived from the same patient population (Wintrob et al., 2017, 2016) [1,2].

GM-CSF and G-CSF are widely used for their benefit in reducing chemotherapy-associated neutropenia. However, whether GM- or G-CSF administration could have tumorigenic or pro-metastatic effects or whether insulin resistance could negatively impact such effects is not known. Their ability to stimulate monocyte production at the same time with the highly sought after neutrophils’ production, enables an enhanced potential for activation of tumor-associated macrophages. At the same time, IL-7 remains the main driver of B and T cell differentiation and maturation, a process linked to the development of insulin resistance and response to diabetes pharmacotherapy. Insulin secretagogues have the potential to interfere with the hematopoiesis process, respectively with the formation of lineages that may lead to a tumorigenic or pro-metastatic phenotype, but this relationship has not been yet investigated. The data presented here shows the relationship between pre-existing use of insulin secretagogues in women diagnosed with breast cancer and type 2 diabetes mellitus, the GM-CSF, G-CSF and IL-7 cytokine profiles at the time of breast cancer diagnosis, and subsequent cancer outcomes. A Pearson correlation analysis evaluating the relationship between investigated cytokines stratified by secretagogue use and controls, and interferon is also provided.

Oral drugs stimulating endogenous insulin production (insulin secretagogues) may have detrimental effects on breast cancer outcomes. The data presented shows the relationship between pre-existing insulin secretagogues use, adipokine profiles at the time of breast cancer (BC) diagnosis and subsequent cancer outcomes in women diagnosed with BC and type 2 diabetes mellitus (T2DM). The Pearson correlation analysis evaluating the relationship between adipokines stratified by T2DM pharmacotherapy and controls is also provided. This information is the extension of the data presented and discussed in “Insulin use, adipokine profiles and breast cancer prognosis” (Wintrob et al., in press) [1].

Objective: In MRI-negative cases Cushing's disease (CD), surgeons perform a more extensive exploration of the pituitary gland, with fewer instances of hormonal remission. 18F-fluoro-deoxy-glucose (18F-FDG) positron emission tomography (PET) has a limited role in detecting adenomas that cause CD (corticotropinomas). Our previous work demonstrated corticotropin-releasing hormone (CRH) stimulation leads to delayed, selective glucose uptake in corticotropinomas. Here, we prospectively evaluated the utility of CRH stimulation in improving 18F-FDG-PET detection of adenomas in CD. Methods: Subjects with a likely diagnosis of CD (n = 27, 20 females) each underwent two 18F-FDG-PET studies [without and with ovine-CRH (oCRH) stimulation] on a high-resolution PET platform. Standardized-uptake-values (SUV) in the sella were calculated. Two blinded neuroradiologists independently read 18F-FDG-PET images qualitatively. Adenomas were histopathologically confirmed, analyzed for mutations in the USP8 gene and for glycolytic pathway proteins. Results: The mean-SUV of adenomas was significantly increased from baseline (3.6 ± 1.5) with oCRH administration (3.9 ± 1.7; one-tailed p = 0.003). Neuroradiologists agreed that adenomas were visible on 21 scans, not visible on 26 scans (disagreed about 7, kappa = 0.7). oCRH-stimulation led to the detection of additional adenomas (n = 6) not visible on baseline-PET study. Of the MRI-negative adenomas (n = 5), two were detected on PET imaging (one only after oCRH-stimulation). USP8 mutations or glycolytic pathway proteins were not associated with SUV in corticotropinomas. Conclusions: The results of the current study suggest that oCRH-stimulation may lead to increased 18F-FDG uptake, and increased rate of detection of corticotropinomas in CD. These results also suggest that some MRI invisible adenomas may be detectable by oCRH-stimulated FDG-PET imaging. Clinical trial information: 18F-FDG-PET imaging with and without CRH stimulation was performed under the clinical trial NIH ID 12-N-0007 (clinicaltrials.gov identifier NCT01459237). The transsphenoidal surgeries and post-operative care was performed under the clinical trial NIH ID 03-N-0164 (clinicaltrials.gov identifier NCT00060541). [ABSTRACT FROM AUTHOR]

Background Pre-operative detection of corticotropin (ACTH) secreting microadenomas causing Cushing's disease (CD) improves surgical outcomes. Current best magnetic resonance imaging fails to detect up to 40% of these microadenomas. 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography (PET) is specific, but not sensitive in detecting corticotropinomas. Theoretically, secretagogue stimulation with corticotropin releasing hormone (CRH) could improve detection of adenomas with 18 F-FDG PET. Previous attempts with simultaneous CRH stimulation have failed to demonstrate increased 18 F-FDG uptake in corticotropinomas. We hypothesized that CRH stimulation leads to a delayed elevation in glucose uptake in corticotropinomas. Methods Clinical data was analyzed for efficacy of CRH in improving 18 FDG-PET detection of corticotropinomas in CD. Glucose transporter 1 (GLUT1) immunoreactivity was performed on surgical specimens. Ex-vivo, viable cells from these tumors were tested for secretagogue effects (colorimetric glucose uptake), and for fate of intracellular glucose (glycolysis stress analysis). Validation of ex-vivo findings was performed with AtT-20 cells. Results CRH increased glucose uptake in human-derived corticotroph tumor cells and AtT-20, but not in normal murine or human corticotrophs (p < 0.0001). Continuous and intermittent (1 h) CRH exposure increased glucose uptake in AtT-20 with maximal effect at 4 h (p = 0.001). Similarly, CRH and 8-Br-cAMP led to robust GLUT1 upregulation and increased membrane translocation at 2 h, while fasentin suppressed baseline (p < 0.0001) and CRH-mediated glucose uptake. Expectedly, intra-operatively collected corticotropinomas demonstrated GLUT1 overexpression. Lastly, human derived corticotroph tumor cells demonstrated increased glycolysis and low glucose oxidation. Conclusion Increased and delayed CRH-mediated glucose uptake differentially occurs in adenomatous corticotrophs. Delayed secretagogue-stimulated 18 F-FDG PET could improve microadenoma detection. [ABSTRACT FROM AUTHOR]

Résumé Les sulfamides hypoglycémiants sont encore largement utilisés par de nombreux patients diabétiques de type 2, principalement en seconde intention et souvent en association avec d’autres molécules antidiabétiques. L’action des glinides, molécules plus récentes, est très proche de celle des sulfamides. Le seul représentant de la classe actuellement sur le marché est le répaglinide. Summary Sulphonylureas are still widely used by many patients with type 2 diabetes, mainly as a second-line treatment and often in combination with other antidiabetic molecules. The action of glinides, more recent molecules, is very similar to that of sulphonylureas. The only representative of the class currently on the market is repaglinide. [ABSTRACT FROM AUTHOR]

Summary The metabolic stress hormone FGF21 is highly expressed in exocrine pancreas, where its levels are increased by refeeding and chemically induced pancreatitis. However, its function in the exocrine pancreas remains unknown. Here, we show that FGF21 stimulates digestive enzyme secretion from pancreatic acinar cells through an autocrine/paracrine mechanism that requires signaling through a tyrosine kinase receptor complex composed of an FGF receptor and β-Klotho. Mice lacking FGF21 accumulate zymogen granules and are susceptible to pancreatic ER stress, an effect that is reversed by administration of recombinant FGF21. Mice carrying an acinar cell-specific deletion of β-Klotho also accumulate zymogen granules but are refractory to FGF21-stimulated secretion. Like the classical post-prandial secretagogue, cholecystokinin (CCK), FGF21 triggers intracellular calcium release via PLC-IP 3 R signaling. However, unlike CCK, FGF21 does not induce protein synthesis, thereby preventing protein accumulation. Thus, pancreatic FGF21 is a digestive enzyme secretagogue whose physiologic function is to maintain acinar cell proteostasis. [ABSTRACT FROM AUTHOR]

Background Type-2 diabetes mellitus (T2DM) and breast cancer (BC) share common cytokine signaling changes resultant from adipose tissue dysfunction. This modified adipokine signaling was shown to be directly associated with changes in the body mass index (BMI) and diet and it is expected to also be influenced by T2DM pharmacotherapy. We evaluated the relationship between pre-existing diabetes treatment, circulating adipokine levels at cancer diagnosis, and long-term outcomes. Methods All incident BC cases were reviewed (01/01/2003-12/31/2009, N = 2194). Each of the subjects with baseline T2DM (cases) was matched with two other subjects without T2DM (controls) based on the following criteria: age, BMI, ethnicity, menopausal status and tumor stage. All cases and controls with available baseline plasma and tumor biopsies, and being surgery and BC treatment naïve, were included (N 1 = 97, N 2 = 194). Clinical history and vital status were documented. Adipokine levels (adiponectin, leptin, TNF-α, CRP, IL-1β, IL-1Ra, IL-6, and C-peptide) were assessed by either ELISA or Luminex® assays. Cancer outcomes were assessed by Kaplan-Meier analysis; associations between categorical variables were assessed by Fisher’s exact test, categorical and continuous variables by Kruskal-Wallis or Wilcoxon Rank-Sum test, where appropriate. Multivariate adjustments (MVP, multivariate p-value) were performed accounting for age, tumor stage, BMI, estrogen receptor (ER) status and cumulative comorbidity. All biomarker correlations were assessed by the Pearson method. Utilization of insulin and insulin secretagogues was associated with ER (−) phenotype (p = 0.008, p = 0.043) and poorer BC outcomes (p = 0.012, p = 0.033). Insulin users were found to have lower C-peptide and higher IL-6, TNF-α and CRP levels, of which elevated CRP and TNF-α were associated with poorer BC outcomes (p = 0.003, MVP = 0.210). Insulin remarked by higher leptin levels as compared to controls (p = 0.052), but did not differ significantly from non-users. Although lower adiponectin levels were observed among non-insulin users as compared to controls (p < 0.001, MVP = 0.006), insulin use seemed to have restored adiponectin production. C-peptide levels were lower among insulin users as compared to non-users (p < 0.001, MVP < 0.001) and approached levels comparable with those of the controls. In the overall dataset, C-peptide lower than 0.75 ng/ml were strongly associated with poorer survival (p = 0.007, MVP = 0.002). Among insulin users, C-peptide levels were inversely correlated with IL-1β and IL-1Ra levels only after full adjustment (p = 0.012, p = 0.030); the correlation was unremarkable in other groups. Conclusion Insulin use is associated with elevated leptin, CRP, TNFα, and lower C-peptide and also linked to poor BC outcomes. More research is needed to verify these findings; however, we are among the first to correlate pharmacotherapy use, measures of adipose tissue dysfunction and cancer outcomes. [ABSTRACT FROM AUTHOR]

Selective GLP-1 secretagogues represent a novel potential therapy for type 2 diabetes mellitus. This study examined the GLP-1 secretory activity of the ethnomedicinal plant, Fagonia cretica , which is postulated to possess anti-diabetic activity. After extraction and fractionation extracts and purified compounds were tested for GLP-1 and GIP secretory activity in pGIP/neo STC-1 cells. Intracellular levels of incretin hormones and their gene expression were also determined. Crude F . cretica extracts stimulated both GLP-1 and GIP secretion, increased cellular hormone content, and upregulated gene expression of proglucagon, GIP and prohormone convertase. However, ethyl acetate partitioning significantly enriched GLP-1 secretory activity and this fraction underwent bioactivity-guided fractionation. Three isolated compounds were potent and selective GLP-1 secretagogues: quinovic acid (QA) and two QA derivatives, QA-3β-O-β- d -glycopyranoside and QA-3β-O-β- d -glucopyranosyl-(28 → 1)-β- d -glucopyranosyl ester. All QA compounds activated the TGR5 receptor and increased intracellular incretin levels and gene expression. QA derivatives were more potent GLP-1 secretagogues than QA. This is the first time that QA and its naturally-occurring derivatives have been shown to activate TGR5 and stimulate GLP-1 secretion. These data provide a plausible mechanism for the ethnomedicinal use of F . cretica and may assist in the ongoing development of selective GLP-1 agonists. [ABSTRACT FROM AUTHOR]