A simplified longitudinal model for the development of Type 2 Diabetes Mellitus.

Obesity and diabetes are a progressively more and more deleterious hallmark of modern, well fed societies. In order to study the potential impact of strategies designed to obviate the pathological consequences of detrimental lifestyles, a model for the development of Type 2 diabetes geared towards large population simulations would be useful. The present work introduces such a model, representing in simplified fashion the interplay between average glycemia, average insulinemia and functional beta-cell mass, and incorporating the effects of excess food intake or, conversely, of physical activity levels. Qualitative properties of the model are formally established and simulations are shown as examples of its use.

Coding variants in PNPLA3 and TM6SF2 are risk factors for hepatic steatosis and elevated serum alanine aminotransferases caused by a glucagon receptor antagonist.

LY2409021 is a glucagon receptor antagonist that was associated with hepatic steatosis and elevated aminotransferases in phase 2 diabetes studies. We investigated the relationship between selected genetic variants and hepatic steatosis and elevated alanine aminotransferases (ALTs) associated with LY2409021. Patients participated in a 6-week placebo-controlled trial (I1R-MC-GLDI [GLDI], n = 246) and a 52-week placebo- and active comparator-controlled trial (I1R-MC-GLDJ [GLDJ], n = 158). GLDJ had endpoints at 6 months, including measures of hepatic fat fraction (HFF) by magnetic resonance imaging. The five genes tested were patatin-like phospholipase domain containing 3 (PNPLA3) (rs738409 and rs738491), transmembrane 6 superfamily member 2 (TM6SF2) (rs58542926), peroxisome proliferative activated receptor gamma coactivator 1 alpha (PPARGC1A) (rs4361373, rs3774921, rs2970849), adenylate cyclase 3 (ADCY3) (rs713586), and insulin-like growth factor 1 (IGF-1) (rs1520220). In GLDI, PNPLA3 I148M (P = 0.001) and TM6SF2 E167K (P = 0.001) were significantly associated with an increase in ALT at 6 weeks for LY2409021 but not for placebo. In GLDJ, PNPLA3 I148M showed the same effect (P = 0.007) on ALT at 6 months but the placebo or sitagliptin did not. In GLDJ, both PNPLA3 and TM6SF2 risk-allele carriers showed increases in HFF that were numerically greater but not statistically significant. The carriers of PNPLA3 and/or TM6SF2 risk alleles showed significantly increased ALT (GLDI, +13.28 U/L in carriers versus +4.84 U/L in noncarriers, P = 4 × 10-5; GLDJ, +14.6 U/L in carriers versus +1.7 in noncarriers, P = 0.0018) and HFF (GLDJ, +5.35% in carriers versus 2.38% in noncarriers, P = 0.048). Elevation of transaminase and HFF were also noted in the noncarriers but at a significantly lower degree. Conclusion: The carriers of PNPLA3 and/or TM6SF2 variant alleles are at risk for hepatic steatosis and elevated ALT levels caused by LY2409021, a glucagon receptor antagonist. More studies are needed to investigate if our observations are generalizable to hepatic steatosis caused by other medications. (Hepatology Communications 2018;2:561-570).

Treatment with LY2409021, a glucagon receptor antagonist, increases liver fat in patients with type 2 diabetes.

AIMS: To evaluate whether treatment with LY2409021, a novel, selective glucagon receptor antagonist, is associated with changes in hepatic fat and other safety variables related to the benefit-risk profile for chronic use in patients with type 2 diabetes (T2D). METHODS: Safety and efficacy were assessed in patients with T2D taking metformin and sulphonylurea who were randomized to LY2409021 20 mg (n = 65), placebo (n = 68), or sitagliptin 100 mg (n = 41). Key endpoints included change from baseline to month 6 in hepatic fat fraction (HFF), assessed by magnetic resonance imaging; hepatic aminotransferases; blood pressure; lipid profile; fasting plasma glucose; and glycated haemoglobin (HbA1c). RESULTS: A significant increase in HFF was seen with LY2409021 vs sitagliptin (least squares [LS] mean difference 3.72%; P < .001) and placebo (4.44%; P < .001), accompanied by significant elevations in alanine aminotransferase levels with LY2409021 vs sitagliptin (6.8 U/L; P = .039) and vs placebo (10.7 U/L; P < .001). No patients had concomitant elevations in bilirubin levels. LY2409021 treatment showed significant HbA1c reductions vs placebo (LS mean difference -0.77%; P < .001) but not sitagliptin (-0.20%; P = .383). Similar results were observed for fasting plasma glucose. LY2409021 was also associated with significant increases in systolic blood pressure vs sitagliptin (4.9 mm Hg; P = .030) and vs placebo (4.3 mm Hg; P = .029), as well as significant increases in body weight and total cholesterol. All effects of LY2409021 were reversible. CONCLUSION: In this cohort of patients with T2D, chronic glucagon receptor antagonism with LY2409021 was associated with glucose-lowering but also demonstrated increases in hepatic fat, hepatic aminotransferases, and other adverse effects.

Treatment with the glucagon receptor antagonist LY2409021 increases ambulatory blood pressure in patients with type 2 diabetes.

AIMS: To assess the effect of LY2409021 on systolic blood pressure (SBP) in patients with type 2 diabetes. MATERIALS AND METHODS: This 6-week, randomized, crossover study evaluated the effects of once-daily administration of LY2409021 20 mg vs those of placebo on SBP, diastolic BP (DBP), and mean arterial pressure (MAP) using 24-hour ambulatory BP monitoring (ABPM) in 270 subjects treated with diet/exercise ± metformin. Other measures included changes in glycemic control, serum lipids, and hepatic safety markers. RESULTS: At 6 weeks of LY2409021 treatment, 24-hour mean SBP was increased, with a least squares mean (LSM) difference of 2.26 mm Hg vs placebo (95% CI: 1.11, 3.40; P < .001). The 24-hour mean DBP and MAP also increased, with LSM differences of 1.37 mm Hg (95% CI: 0.66, 2.08; P < .001) and 1.67 mm Hg (95% CI: 0.86, 2.47; P < .001) vs placebo, respectively. At week 6, LY2409021 treatment reduced glycated hemoglobin (HbA1c) levels, with an LSM difference of -0.49% (-5.4 mmol/mol) (95% CI: -0.56%, -0.42% [-6.1, -4.6 mmol/mol]; P < .001) vs placebo. Mean HbA1c at baseline was 7.3% (56 mmol/mol). Small but significant changes in serum lipid and aminotransferase levels were observed with LY2409021 treatment (all P < .05 vs placebo). CONCLUSIONS: Statistically significant increases in BP, MAP and serum lipid levels were observed with LY2409021 treatment at a dose that lowered HbA1c and glucose levels. These effects may limit the clinical utility of LY2409021 as a chronic treatment for type 2 diabetes.

Evaluation of Efficacy and Safety of the Glucagon Receptor Antagonist LY2409021 in Patients With Type 2 Diabetes: 12- and 24-Week Phase 2 Studies.

OBJECTIVE: Type 2 diabetes pathophysiology is characterized by dysregulated glucagon secretion. LY2409021, a potent, selective small-molecule glucagon receptor antagonist that lowers glucose was evaluated for efficacy and safety in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: The efficacy (HbA1c and glucose) and safety (serum aminotransferase) of once-daily oral administration of LY2409021 was assessed in two double-blind studies. Phase 2a study patients were randomized to 10, 30, or 60 mg of LY2409021 or placebo for 12 weeks. Phase 2b study patients were randomized to 2.5, 10, or 20 mg LY2409021 or placebo for 24 weeks. RESULTS: LY2409021 produced reductions in HbA1c that were significantly different from placebo over both 12 and 24 weeks. After 12 weeks, least squares (LS) mean change from baseline in HbA1c was -0.83% (10 mg), -0.65% (30 mg), and -0.66% (60 mg) (all P < 0.05) vs. placebo, 0.11%. After 24 weeks, LS mean change from baseline in HbA1c was -0.45% (2.5 mg), -0.78% (10 mg, P < 0.05), -0.92% (20 mg, P < 0.05), and -0.15% with placebo. Increases in serum aminotransferase, fasting glucagon, and total fasting glucagon-like peptide-1 (GLP-1) were observed; levels returned to baseline after drug washout. Fasting glucose was also lowered with LY2409021 at doses associated with only modest increases in aminotransferases (mean increase in alanine aminotransferase [ALT] ≤10 units/L). The incidence of hypoglycemia in the LY2409021 groups was not statistically different from placebo. CONCLUSIONS: In patients with type 2 diabetes, glucagon receptor antagonist treatment significantly lowered HbA1c and glucose levels with good overall tolerability and a low risk for hypoglycemia. Modest, reversible increases in serum aminotransferases were observed.

Early evaluation of patient risk for substantial weight gain during olanzapine treatment for schizophrenia, schizophreniform, or schizoaffective disorder.

BACKGROUND: To make well informed treatment decisions for their patients, clinicians need credible information about potential risk for substantial weight gain. We therefore conducted a post-hoc analysis of clinical trial data, examining early weight gain as a predictor of later substantial weight gain. METHODS: Data from 669 (Study 1) and 102 (Study 2) olanzapine-treated patients diagnosed with schizophrenia, schizophreniform, or schizoaffective disorder were analyzed to identify and validate weight gain cut-offs at Weeks 1-4 that were predictive of substantial weight gain (defined as an increase of > or = 5, 7, 10 kg or 7% of baseline weight) after approximately 30 weeks of treatment. Baseline characteristics alone, baseline characteristics plus weight change from baseline to Weeks 1, 2, 3 or 4, and weight change from baseline to Weeks 1, 2, 3, or 4 alone were evaluated as predictors of substantial weight gain. Similar analyses were performed to determine BMI increase cut-offs at Weeks 1-4 of treatment that were predictive of substantial increase in BMI (1, 2 or 3 kg/m2 increase from baseline). RESULTS: At Weeks 1 and 2, predictions based on early weight gain plus baseline characteristics were more robust than those based on early weight gain alone. However, by Weeks 3 and 4, there was little difference between the operating characteristics associated with these two sets of predictors. The positive predictive values ranged from 30.1% to 73.5%, while the negative predictive values ranged from 58.1% to 89.0%. Predictions based on early BMI increase plus baseline characteristics were not uniformly more robust at any time compared to those based on early BMI increase alone. The positive predictive values ranged from 38.3% to 83.5%, while negative predictive values ranged from 42.1% to 84.7%. For analyses of both early weight gain and early BMI increase, results for the validation dataset were similar to those observed in the primary dataset. CONCLUSION: Results from these analyses can be used by clinicians to evaluate risk of substantial weight gain or BMI increase for individual patients. For instance, negative predictive values based on data from these studies suggest approximately 88% of patients who gain less than 2 kg by Week 3 will gain less than 10 kg after 26-34 weeks of olanzapine treatment. Analysis of changes in BMI suggests that approximately 84% of patients who gain less than .64 kg/m2 in BMI by Week 3 will gain less than 3 kg/m2 in BMI after 26-34 weeks of olanzapine treatment. Further research in larger patient populations for longer periods is necessary to confirm these results.

Double-blind, randomized trial comparing efficacy and safety of continuing olanzapine versus switching to quetiapine in overweight or obese patients with schizophrenia or schizoaffective disorder.

We examined the potential risks and benefits of switching from olanzapine to quetiapine in mentally stable, obese, or overweight patients with schizophrenia or schizoaffective disorder. Patients receiving olanzapine were randomized to continuing olanzapine treatment (N =68; 7.5-20 mg/day) or switching to quetiapine (N =65; 300-800 mg/day). Time to relapse was the primary study objective; secondary objectives included changes in weight, metabolic parameters, and psychiatric symptoms, and discontinuation rates. No significant difference in time to relapse was observed (p =0.293), but significantly more patients remained on treatment in the olanzapine group compared with the quetiapine group (70.6% vs 43.1%; p =0.002). Olanzapine-treated patients had significantly lower rates of study discontinuation for lack of efficacy and psychiatric adverse events (AEs) compared to quetiapine (2.94% vs 15.38%, p =0.015). Significantly more patients in the olanzapine group experienced an increase in BMI ≥1 kg/m(2). Olanzapine-treated patients experienced significantly greater increases in weight from Weeks 2 through 13. Switching patients with stable disease from olanzapine to quetiapine did not significantly shorten time to relapse, but produced more frequent study discontinuations due to lack of efficacy or psychiatric AEs with moderate but variable improvement in weight and no significant between-group differences in mean changes in metabolic laboratory parameters.

Cross-sectional comparison of fasting lipids in normoglycemic patients with schizophrenia during chronic treatment with olanzapine, risperidone, or typical antipsychotics.

We compared fasting lipids and other metabolic parameters in 211 normoglycemic patients meeting the DSM-IV diagnosis of schizophrenia or schizoaffective disorder undergoing continuous treatment with olanzapine, risperidone, or typical antipsychotics for at least 1 year. Blood samples were obtained after an 11-hour (+/-1 h) observed fast. Olanzapine-treated patients had significantly higher mean fasting triglyceride levels (2.3 +/- 1.8 mmol/L) than risperidone- (1.7 +/- 0.9 mmol/L, P = 0.022), but not typical antipsychotic-treated patients (1.8 +/- 1 mmol/L). There were no significant differences in total low-density (LDL-C) or high-density lipoprotein cholesterol levels. Apolipoprotein-B and very low density lipoprotein cholesterol levels were significantly higher in the olanzapine- versus risperidone-treated patients, but there were no significant differences between olanzapine- and typical antipsychotic-treated patients. Treatment groups did not differ significantly in LDL particle size, the prevalence of an "atherogenic" lipid profile, or estimated insulin sensitivity. Although interpretation of this study is limited by the cross-sectional study design, it provides additional insight concerning the relationship between antipsychotic use and plasma lipid parameters in this population.

Retrospective analysis of diabetes risk in elderly patients with dementia in olanzapine clinical trials.

OBJECTIVE: The objective of this study was to evaluate the association of established risk factors for treatment-emergent diabetes (TED) among patients over 65 years of age with dementia who received treatment with olanzapine. METHODS: This was a post hoc analysis of data pooled from seven olanzapine clinical trials, which included patients over 65 years of age with dementia. The association of established risk factors for TED was evaluated using categorical and time-to-event analysis. TED was defined as two casual (fasting or nonfasting) glucose values > or =200 mg/dL at any time after baseline or one casual glucose value > or =200 mg/dL at the final visit, initiation of antidiabetic medication, or new clinical diagnosis of diabetes. RESULTS: Elderly patients subsequently identified with TED (N = 29, 2.1%) had similar baseline body mass indices (24 kg/m(2)) and were similar in age (82 versus 80 years) to those who did not have TED. Cox proportional hazards model identified only elevated casual glucose (> or =140 mg/dL) measure at baseline to be significantly associated with the development of TED (hazard ratio [HR] = 11.2, p <0.0001) in this elderly cohort. Other clinical risk factors, like body mass index > or =25 (HR = 0.86), 7% weight gain (HR = 2.26), and antipsychotic treatment (HR = 1.36) were not significant. CONCLUSION: In elderly patients with dementia enrolled in olanzapine clinical trials, an elevated casual glucose (> or =140 mg/dL) at baseline was the only risk factor significantly associated with subsequent development of TED. Risk of diabetes in these studies was not significantly associated with antipsychotic treatment group assignment.

Retrospective cohort study of diabetes mellitus and antipsychotic treatment in a geriatric population in the United States.

OBJECTIVES: The objective of this study was to investigate risk of diabetes among elderly patients during treatment with antipsychotic medications. DESIGN: We conducted a longitudinal, retrospective study assessing the incidence of new prescription claims for antihyperglycemic agents during antipsychotic therapy. SETTING: Prescription claims from the AdvancePCS claim database were followed for 6 to 9 months. PARTICIPANTS: Study participants consisted of patients in the United States aged 60+ and receiving antipsychotic monotherapy. The following cohorts were studied: an elderly reference population (no antipsychotics: n = 1,836,799), those receiving haloperidol (n = 6481) or thioridazine (n = 1658); all patients receiving any conventional antipsychotic monotherapy (n = 11,546), clozapine (n = 117), olanzapine (n = 5382), quetiapine (n = 1664), and risperidone (n = 12,244), and all patients receiving any atypical antipsychotic monotherapy (n = 19,407). MEASUREMENTS: We used Cox proportional hazards regression to determine the risk ratio of diabetes for antipsychotic cohorts relative to the reference population. Covariates included sex and exposure duration. RESULTS: New antihyperglycemic prescription rates were higher in each antipsychotic cohort than in the reference population. Overall rates were no different between atypical and conventional antipsychotic cohorts. Among individual antipsychotic cohorts, rates were highest among patients treated with thioridazine (95% confidence interval [CI], 3.1- 5.7), lowest with quetiapine (95% CI, 1.3-2.9), and intermediate with haloperidol, olanzapine, and risperidone. Among atypical cohorts, only risperidone users had a significantly higher risk (95% CI, 1.05-1.60; P = 0.016) than for haloperidol. Conclusions about clozapine were hampered by the low number of patients. CONCLUSION: These data suggest that diabetes risk is elevated among elderly patients receiving antipsychotic treatment. However, causality remains to be demonstrated. As a group, the risk for atypical antipsychotic users was not significantly different than for users of conventional antipsychotics.

Coordinate regulation of L-arginine uptake and nitric oxide synthase activity in cultured endothelial cells.

Despite intracellular L-arginine concentrations that should saturate endothelial nitric oxide synthase (eNOS), nitric oxide production depends on extracellular L-arginine. We addressed this 'arginine paradox' in bovine aortic endothelial cells by simultaneously comparing the substrate dependence of L-arginine uptake and intracellular eNOS activity, the latter measured as L-[3H]arginine conversion to L-[3H]citrulline. Whereas the Km of eNOS for L-arginine was 2 microM in cell extracts, the L-arginine concentration of half-maximal eNOS stimulation was increased to 29 microM in intact cells. This increase likely reflects limitation by L-arginine uptake, which had a Km of 108 microM. The effects of inhibitors of endothelial nitric oxide synthesis also suggested that extracellular L-arginine availability limits intracellular eNOS activity. Treatment of intact cells with the calcium ionophore A23187 reduced the L-arginine concentration of half-maximal eNOS activity, which is consistent with a measured increase in L-arginine uptake. Increases in eNOS activity induced by several agents were closely correlated with enhanced L-arginine uptake into cells (r = 0.89). The 'arginine paradox' may be explained in part by regulated L-arginine uptake into a compartment, probably represented by caveolae, that contains eNOS and that is distinct from the bulk cytosolic L-arginine.