Trends of HbA1c and BMI in People with Type 2 Diabetes: A Japanese Claims-Based Study.

INTRODUCTION: Obesity prevalence has increased in Japan in recent years. Given the strong association of obesity with poor glycemic control, and increased risk of type 2 diabetes (T2D) with central obesity, this study describes the current trends and relationships between glycated hemoglobin (HbA1c), body mass index (BMI), and waist circumference in the Japanese people with T2D. METHODS: This was a retrospective, cross-sectional study of people with T2D who had at least one recorded HbA1c and BMI (or waist circumference) value in the Japan Medical Data Center Claims database. Five annual cohorts of the study population were formed between January 2017 and December 2021. Annual trends of HbA1c across BMI categories (obesity class I [≥ 25 ~ < 30 kg/m2]-IV [≥ 40 kg/m2]) and in people with central obesity (waist circumference: ≥ 85 cm in men; ≥ 90 cm in women) were described by sex and age groups. RESULTS: Overall, 106,089 people with T2D (HbA1c and BMI data: 106,079; HbA1c and waist circumference data: 105,424) were included, with the majority of people belonging to obesity class I (range: 39.7-40.6%) and obesity class II (range: 16.2-17.7%) categories across all annual cohorts. People in higher BMI categories had higher mean HbA1c, with > 50% of people with T2D in obesity class I-IV (54.8-56.5%) having HbA1c ≥ 7%. Between 2017 and 2021, BMI and waist circumference increased in the age group 18-44 years. More than 50% of people with T2D and central obesity in both sexes and people of age group 18-44 years across obesity class I-IV or with central obesity had HbA1c ≥ 7%. CONCLUSION: More than half of the people with T2D belonging to obesity class I-IV or central obesity had poor glycemic control (HbA1c ≥ 7%), especially in the 18-44 age group. This highlights the need for body weight management for better glycemic control in relatively young Japanese people with T2D and obesity.

Prevalence of Metabolic Syndrome in Patients with Type 2 Diabetes in Japan: A Retrospective Cross-Sectional Study.

INTRODUCTION: Recent data on the prevalence of metabolic syndrome in Japanese patients with type 2 diabetes (T2D) are limited. METHODS: This retrospective, cross-sectional, observational study investigated the prevalence of metabolic syndrome in patients with T2D using a Japanese administrative claims database. Patients with a T2D diagnosis, prescription of a hypoglycemic agent, and one or more annual health checkups in 2020 were included. Trends in the prevalence of metabolic syndrome by sex and body mass index (BMI) subgroup were assessed. RESULTS: The study cohort consisted of 155,653 patients (men, 81.6%; mean age 54.6 ± 8.5 years). Patients with metabolic syndrome had a higher mean BMI (29.1 ± 4.5 kg/m2 versus 25.2 ± 4.5 kg/m2) and mean waist circumference (98.3 ± 10.0 cm versus 87.9 ± 11.2 cm) compared to those without metabolic syndrome. Overall, the prevalence of metabolic syndrome was 43.0% in patients with T2D, with prevalence higher in men (46.6%) than women (27.0%). The prevalence increased across BMI subgroups from 17.3% in the < 25 kg/m2 subgroup, to 54.6% and 66.1% in the 25 to < 30 and ≥ 30 kg/m2 subgroups, respectively. A greater proportion of patients with metabolic syndrome had cardiovascular or renal comorbidities (BMI < 25, 0.3-2.0%; BMI 25 to < 30, 0.7-6.2%; BMI ≥ 30 kg/m2, 0.7-6.8%) and cardiovascular drug usage (BMI < 25, 1.3-9.0%; BMI 25 to < 30, 3.8-31.1%; BMI ≥ 30 kg/m2, 3.5-37.0%) in the higher BMI subgroups compared to the BMI < 25 kg/m2 subgroup. CONCLUSION: The prevalence of metabolic syndrome in Japanese patients with T2D was 43.0% and increased with higher BMI. In patients with T2D and metabolic syndrome, cardiovascular drug usage and comorbidities increased in patients with a higher BMI. These data highlight the importance of managing metabolic parameters in addition to glycemic control in Japanese patients with T2D, particularly in patients with metabolic syndrome and BMI ≥ 25 kg/m2.

Glycaemic control, body weight, and safety of tirzepatide versus dulaglutide by baseline glycated haemoglobin level in Japanese patients with type 2 diabetes: A subgroup analysis of the SURPASS J-mono study.

AIM: To evaluate glycaemic control, body weight, and safety outcomes following treatment with tirzepatide or dulaglutide in patients with type 2 diabetes (T2D) with a baseline haemoglobin (HbA1c) level of ≤8.5% (≤69 mmol/mol) versus >8.5% (>69 mmol/mol). MATERIALS AND METHODS: SURPASS J-mono was a 52-week, multicentre, randomized, double-blind, parallel, active-controlled, phase 3 study conducted in Japan. In this exploratory subgroup analysis of SURPASS J-mono, we examined mean change in HbA1c and body weight and the incidence of adverse events (AEs) in patients with a baseline HbA1c of ≤8.5% versus >8.5% after treatment with tirzepatide (5, 10 or 15 mg) or dulaglutide 0.75 mg. RESULTS: Of 636 randomized participants, 203 had a baseline HbA1c of >8.5% and 433 had a baseline HbA1c of ≤8.5% (range ≥7.0% to ≤10.0%). Both subgroups showed significantly greater reductions in HbA1c and body weight with any-dose tirzepatide versus dulaglutide 0.75 mg, with greater HbA1c reductions observed in patients with a baseline HbA1c of >8.5% treated with tirzepatide (least squares mean [LSM] differences of -3.13% to -3.86%) or dulaglutide (LSM -1.81%) compared with patients with a baseline HbA1c of ≤8.5% (LSM -2.00% to -2.32%) or dulaglutide (LSM -1.05%; treatment-by-baseline HbA1c subgroup interaction P ≤ 0.001). For the tirzepatide treatment arms, LSM change from baseline in body weight ranged from -6.7 to -10.7 kg for the baseline HbA1c ≤8.5% subgroup and from -4.0 to -10.6 kg for the baseline HbA1c >8.5% subgroup, compared with -0.6 kg and -0.4 kg, respectively, for the dulaglutide arm. The incidence of hypoglycaemia was low, with no substantial difference in hypoglycaemia or treatment-emergent AEs between subgroups. CONCLUSIONS: Regardless of baseline HbA1c (≤8.5% or >8.5%), tirzepatide at doses of 5, 10 and 15 mg is effective in Japanese patients with T2D compared with dulaglutide 0.75 mg in terms of glycaemic control and body weight reduction, with an adequate safety profile consistent with previous reports.

Cost-effectiveness analysis of empagliflozin in patients with heart failure with reduced ejection fraction in Japan based on the EMPEROR-Reduced trial.

BACKGROUND: Several studies have reported the cost-effectiveness of sodium-glucose co-transporter 2 inhibitors in heart failure patients; however, their economic implications have not been sufficiently elucidated in Japan. METHODS: A Markov cohort model was developed to evaluate the cost-effectiveness of empagliflozin plus standard of care (SoC) vs. SoC for patients with heart failure with reduced ejection fraction (HFrEF) in Japan. Model inputs, including risk of clinical events, costs, and utilities based on Kansas City Cardiomyopathy Questionnaire Clinical Summary Scores were derived from EMPEROR-Reduced trial data, published literature, and a claims database. RESULTS: The model predicted lower lifetime hospitalizations for heart failure (HHFs) and additional quality-adjusted life-years (QALYs; 0.21) for empagliflozin plus SoC vs. SoC in the overall population. Increased costs of ¥100,495/patient ($772/patient), primarily driven by higher drug costs of ¥239,558/patient ($1,840/patient), were largely offset by reduced HHF management costs of -¥166,160/patient (-$1,276/patient), yielding an incremental cost-effectiveness ratio (ICER) of ¥469,672/QALY ($3,608/QALY). Results were consistent among subgroups and sensitivity analyses. In probabilistic sensitivity analysis, 82.5 % of runs were below the Japanese ICER reference value of ¥5,000,000/QALY ($38,408/QALY). CONCLUSIONS: Empagliflozin was demonstrated to be cost-effective for HFrEF patients in Japan based on the EMPEROR-Reduced trial data.

Safety and efficacy analyses across age and body mass index subgroups in East Asian participants with type 2 diabetes in the phase 3 tirzepatide studies (SURPASS programme).

AIM: To assess the safety and efficacy of tirzepatide in people of East Asian descent based on age and body mass index (BMI). MATERIALS AND METHODS: Data of participants enrolled in East Asian countries in the SURPASS-1, -3, -4, -5, J-mono and J-combo phase 3 clinical trials were included. Participants with type 2 diabetes with a baseline HbA1c of 7.0% up to 11.0% and a BMI of 23 kg/m2 or greater or 25 kg/m2 or greater were included. Participants treated with tirzepatide 5, 10 or 15 mg were evaluated to assess the safety and efficacy of tirzepatide in people of East Asian descent (94% from Japan) based on age (< 65 and ≥ 65 years) and BMI (< 25 and ≥ 25 kg/m2 ). Key safety and efficacy outcomes were assessed. RESULTS: At baseline, 73% of East Asian participants had a BMI of 25 kg/m2 or greater and 74% were younger than 65 years. At week 52, tirzepatide induced a similar dose-dependent reduction in HbA1c, waist circumference and BMI across subgroups. Across all BMI and age subgroups, mean absolute HbA1c reductions across the three doses ranged from 2.3% to 3.0%, and mean waist circumference reductions ranged from 4.3 to 9.8 cm. Improvements in absolute insulin sensitivity, assessed by homeostatic model assessment for insulin resistance, were greater in those with a baseline BMI of ≥ 25 kg/m2 . Improvements in lipid profiles were similar across subgroups. While the safety profile of tirzepatide was broadly similar across BMI and age subgroups, drug discontinuation because of adverse events was higher in participants with a baseline age of ≥ 65 years. CONCLUSIONS: This post hoc analysis showed that once-weekly tirzepatide had a similar safety and efficacy profile across BMI and age subgroups in East Asian participants.

Cost-Effectiveness Analysis of Linagliptin in Japan Based on Results from the Asian Subpopulation in the CARMELINA® Trial.

INTRODUCTION: We evaluated the cost-effectiveness of linagliptin in Japan by estimating the lifetime outcome based on clinical event rates from the Asian subpopulation of the CARMELINA trial. In CARMELINA, linagliptin added to standard of care (SoC) versus SoC demonstrated noninferiority with regard to risk of composite cardiovascular (CV) outcome in patients with type 2 diabetes at high risk of CV and kidney events. Issues resulting from conducting a cost-effectiveness analysis using data from a clinical noninferiority study were also investigated. METHODS: A microsimulation model was used to evaluate linagliptin/SoC versus SoC in terms of direct costs and quality-adjusted life years (QALYs) from a Japanese public healthcare payer's perspective. Cost data were obtained from recent Japanese publications. The time horizon was defined as lifetime, and the discount rate for costs and effectiveness was 2% per year. One-way and probabilistic sensitivity analyses were performed. RESULTS: In the base case analysis, and taking medical history into account, the incremental effectiveness of linagliptin/SoC versus SoC was 1.34 QALYs, and the incremental cost for linagliptin was - 545,319 yen. In the one-way sensitivity analysis, the parameter which most affected the results was the hazard ratio for renal failure of linagliptin/SoC compared with SoC. The probabilistic sensitivity analysis showed that the probability of reduced costs and increased effectiveness (dominant) was 48%. Assuming an incremental cost-effectiveness ratio (ICER) threshold of 5 million yen, the probability that the ICER was below the threshold was 89% for linagliptin/SoC compared with SoC. CONCLUSIONS: This evaluation, using Asian subpopulation data from the CARMELINA trial, suggested that the cost-effectiveness of linagliptin for a lifetime outcome was favourable in Japan. However, the results must be interpreted cautiously because of the noninferiority trial data source, which might cause ICER variations for each parameter.

Long-Term Safety and Effectiveness of Linagliptin in Japanese Patients with Type 2 Diabetes and Renal Dysfunction: a Post-Marketing Surveillance Study.

INTRODUCTION: International clinical trials have shown that linagliptin significantly improves glycemic control and can be used at a single dose regardless of renal function in patients with type 2 diabetes (T2D). However, to date, no studies have evaluated the use of linagliptin in Japanese patients with T2D by renal function in routine clinical care. METHODS: This was a subgroup analysis of data from a prospective observational post-marketing surveillance (PMS) study of linagliptin conducted in Japan that evaluated the safety and effectiveness of linagliptin in routine clinical care for 3 years in Japanese patients with T2D. The subgroup analysis examined the patient population of this PMS study according to renal function using estimated glomerular filtration rate (eGFR) data. The incidence of linagliptin-related adverse events (adverse drug reactions [ADRs]) was the primary endpoint, and the change in glycated hemoglobin (HbA1c) from baseline to last observation was the secondary endpoint. RESULTS: Of the 2235 patients included in the safety analysis, eGFR was ≥ 90 mL/min/1.73 m2 (defined as group G1) in 16.9% (n = 377), ≥ 60 to < 90 mL/min/1.73 m2 (group G2) in 44.5% (n = 995), ≥ 30 to < 60 mL/min/1.73 m2 (group G3) in 21.7% (n = 486), ≥ 15 to < 30 mL/min/1.73 m2 (group G4) in 2.6% (n = 58) and < 15 mL/min/1.73 m2 (group G5) in 1.7% (n = 37). No eGFR data were available for 12.6% (n = 282) of patients. In these GFR groups, the incidence of ADRs with linagliptin was 6.9% in group G1, 11.1% in group G2, 13.8% in group G3, 15.5% in group G4 and 16.2% in group G5; the change in HbA1c from baseline to the last observation was - 1.11, - 0.64, - 0.35, - 0.46 and - 0.54% in the respective subgroups. CONCLUSIONS: Long-term linagliptin use showed sustained improvements in glycemic control with no new safety concerns regardless of renal function. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01650259). FUNDING: This study was funded by Nippon Boehringer Ingelheim Co., Ltd. and Eli Lilly Japan K.K.

Cost-effectiveness Analysis of Empagliflozin in Japan Based on Results From the Asian subpopulation in the EMPA-REG OUTCOME Trial.

PURPOSE: The goal of this study was to assess the cost-effectiveness of empagliflozin in Japan based on the Asian subpopulation in the EMPA-REG OUTCOME trial. METHODS: The trial has shown a reduction in the risk for cardiovascular (CV) and renal events with empagliflozin in patients with type 2 diabetes mellitus and established CV disease. A cost-effectiveness analysis based on the overall population of the EMPA-REG OUTCOME trial was reported previously by using a lifetime discrete event simulation model. The same modeling frame was adapted to evaluate the cost-effectiveness of treatment with empagliflozin added to standard of care (SoC) compared with SoC alone in Japan. The time to relevant clinical events and the hazard ratios were derived from an Asian subpopulation in the EMPA-REG OUTCOME trial. The costs for each event were estimated from a Japanese medical claims database. Direct medical costs, life expectancy, and quality-adjusted life years (QALYs) were calculated from the public health care perspective. FINDINGS: Treatment with empagliflozin was estimated to increase life expectancy by 6.2 years and 2.7 QALYs, whereas total cost increased by 1,115,475 yen compared with treatment with SoC alone. The incremental cost-effectiveness ratio was 415,849 yen/QALY. In the sensitivity analysis, there was no case that was in excess of the reference value of the incremental cost-effectiveness ratio in the pilot introduction for price revision in Japan (ie, 5 million yen/QALY). IMPLICATIONS: Based on the Asian subpopulation in the EMPA-REG OUTCOME trial, our results suggest that empagliflozin added to SoC is highly cost-effective compared with SoC alone in Japan.

Empagliflozin Induces Transient Diuresis Without Changing Long-Term Overall Fluid Balance in Japanese Patients With Type 2 Diabetes.

INTRODUCTION: Empagliflozin, a sodium glucose co-transporter 2 (SGLT2) inhibitor, ameliorates hyperglycemia in patients with type 2 diabetes (T2D) by inducing sustained glucosuria. Empagliflozin treatment was previously associated with a transient increase in 24-h urine volume in Caucasian patients with T2D, however comparable evidence in Japanese T2D individuals is scarce. We therefore assessed acute and chronic changes in 24-h urine volume and fluid intake with empagliflozin in Japanese patients with T2D. METHODS: In this randomized, double-blind, placebo-controlled, parallel-group, multiple-dose, 4-week trial, 100 Japanese patients with T2D were randomized to receive either 1, 5, 10, or 25 mg empagliflozin or placebo once-daily. Changes from baseline in 24-h urine volume and fluid intake were assessed at days 1, 27, and 28 after the initiation of empagliflozin. RESULTS: The 24-h urine volume and fluid intake were comparable across all treatment groups at baseline. Patients treated with either 10 or 25 mg empagliflozin (i.e., the licensed doses in Japan) showed a significant increase in 24-h urine volume compared to placebo at day 1 (mean change from baseline: + 0.83, + 1.08, and + 0.29 L/day in the empagliflozin 10 and 25 mg groups and the placebo group, respectively; both p < 0.001 vs. placebo). However, 24-h urine volume levels in the empagliflozin groups were comparable to placebo at day 27 and 28 (differences vs placebo < 0.1 L/day; p > 0.05). The 24-h fluid intake was comparable across all study groups throughout the entire study period. No events consistent with dehydration were reported during empagliflozin treatment. CONCLUSION: Treatment initiation with empagliflozin in Japanese patients with T2D was associated with transient diuresis; however, overall urine volume returned towards baseline levels within 4 weeks of treatment. These findings are consistent with a physiological, adaptive mechanism of the kidney to maintain overall body fluid balance in response to treatment initiation with a SGLT2 inhibitor. TRIAL REGISTRATION NUMBER: NCT00885118. FUNDING: Nippon Boehringer Ingelheim Co., Ltd.

Role of AMPD2 in impaired glucose tolerance induced by high fructose diet.

A high intake of products containing fructose is known to mediate insulin resistance. In the liver, AMPD2, an isoform of AMPD, has important glucose metabolic homeostasis functions including maintenance of AMP-activated protein kinase (AMPK). We speculated that AMPD2 induces impaired glucose tolerance in individuals who consume a high-fructose diet. We gave either a normal-chow (NCD) or high-fructose (HFrD) diet for 40 days to 8-week-old male wild-type (WT) and Ampd2 -/- homozygote (A2 -/-) C57BL/6 mice. A glucose tolerance test (GTT) and pyruvate tolerance test (PTT) were used to evaluate glucose metabolism. In addition, gluconeogenesis and glycolysis enzymes, and AMPK phosphorylation in the liver were investigated. With consumption of the HFrD, A2 -/- mice showed enhanced glucose tolerance in GTT and PTT results as compared to the WT mice, which were independent of changes in body weight. Also, the levels of phosphoenolpyruvate carboxy kinase and glucose-6-phosphatase (hepatic gluconeogenic enzymes) were significantly reduced in A2 -/- as compared to WT mice. The hepatic glycolytic enzymes glucokinase, phosphofructokinase, and pyruvate kinase were also examined, though there were no significant differences between genotypes in regard to both mRNA expression and protein expression under HFrD. Surprisingly, hepatic AMPK phosphorylation resulted in no changes in the A2 -/- as compared to WT mice under these conditions. Our results indicated that Ampd2-deficient mice are protected from high fructose diet-induced glycemic dysregulation, mainly because of gluconeogenesis inhibition, and indicate a novel therapeutic target for type 2 diabetes mellitus.

Pentraxin-3 regulates the inflammatory activity of macrophages.

BACKGROUND AND AIMS: Pentraxin-3 (PTX3) reportedly has protective roles in atherosclerosis and myocardial infarction, and is a useful biomarker of vascular inflammation. However, the detailed functions of PTX3 in inflammation are yet to be elucidated. This study aimed to investigate the function of PTX3 in macrophages. METHODS: PMA-treated THP-1 cell line (THP-1 macrophage) and monocyte-derived human primary macrophages were treated with recombinant PTX3. Cytokine and chemokine levels in the THP-1 culture medium were measured as well as monocyte chemoattractant protein (MCP-1) concentrations in the Raw 264.7 cell culture medium. PTX3-silenced apoptotic macrophages (THP-1 cell line) were generated to investigate the roles of PTX3 in phagocytosis. RESULTS: In the presence of PTX3, macrophage interleukin-1ß (IL-1ß), tumor necrosis factor-alpha (TNF-α) and MCP-1 levels were reduced significantly (-39%, P=0.007; -21%, P=0.008; and -67%, P=0.0003, respectively), whilst activated transforming growth factor-ß (TGF-ß) was detected in the THP-1 macrophages (P=0.0004). Additionally, PTX3 induced Akt phosphorylation and reduced nuclear factor-kappa B (NF-κB) activation by 35% (P=0.002), which was induced by TNF-α in THP-1 macrophages. Furthermore, silencing of PTX3 in apoptotic cells resulted in increased macrophage binding, elevated expression rate of HLA-DR (+30%, P=0.015) and CD86 (+204%, P=0.004) positive cells, and induction of IL-1ß (+36%, P=0.024) production. Conversely, adding recombinant PTX3 to macrophages reduced CD86 and HLA-DR expression in a dose-dependent manner. CONCLUSIONS: We identified PTX3 as a novel regulator of macrophage activity, and this function suggests that PTX3 acts to resolve inflammation.

AMPD1 regulates mTORC1-p70 S6 kinase axis in the control of insulin sensitivity in skeletal muscle.

BACKGROUND: Insulin resistance triggered by excess fat is a key pathogenic factor that promotes type 2 diabetes. Understanding molecular mechanisms of insulin resistance may lead to the identification of a novel therapeutic target for type 2 diabetes. AMPD1, an isoform of AMP deaminase (AMPD), is suggested to play roles in the regulation of glucose metabolism through controlling AMP-activated protein kinase (AMPK) activation. We reported that the diet-induced insulin resistance was improved in AMPD1-deficient mice compared to wild type mice. To further delineate this observation, we studied changes of insulin signaling in skeletal muscle of wild type (WT) and AMPD1-deficient mice. METHODS: Phosphorylation levels of kinases and expression levels of mTOR components were quantified by immunoblotting using protein extracts from tissues. The interaction between mTOR and Raptor was determined by immunoblotting of mTOR immunoprecipitates with anti-Raptor antibody. Gene expression was studied by quantitative PCR using RNA extracted from tissues. RESULTS: Phosphorylation levels of AMPK, Akt and p70 S6 kinase in skeletal muscle were higher in AMPD1-deficient mice compared to WT mice after high fat diet challenge, while they did not show such difference in normal chow diet. Also, no significant changes in phosphorylation levels of AMPK, Akt or p70 S6 kinase were observed in liver and white adipose tissue between WT and AMPD1-deficient mice. The expression levels of mTOR, Raptor and Rictor tended to be increased by AMPD1 deficiency compared to WT after high fat diet challenge. AMPD1 deficiency increased Raptor-bound mTOR in skeletal muscle compared to WT after high fat diet challenge. Gene expression of peroxisome proliferator-activated receptor-γ coactivator 1α and ß, downstream targets of p70 S6 kinase, in skeletal muscles was not changed significantly by AMPD1 deficiency compared to the wild type after high fat diet challenge. CONCLUSION: These data suggest that AMPD1 deficiency activates AMPK/Akt/mTORC1/p70 S6 kinase axis in skeletal muscle after high fat diet challenge, but not in normal chow diet. These changes may contribute to improve insulin resistance.

AMPD1: a novel therapeutic target for reversing insulin resistance.

BACKGROUND: Insulin resistance is one of the hallmark manifestations of obesity and Type II diabetes and reversal of this pathogenic abnormality is an attractive target for new therapies for Type II diabetes. A recent report that metformin, a drug known to reverse insulin resistance, demonstrated in vitro the metformin can inhibit AMP deaminase (AMPD) activity. Skeletal muscle is one of the primary organs contributing to insulin resistance and that the AMPD1 gene is selectively expressed at high levels in skeletal muscle. METHODS: Recognizing the background above, we asked if genetic disruption of the AMPD1 gene might ameliorate the manifestations of insulin resistance. AMPD1 deficient homozygous mice and control mice fed normal chow diet or a high-fat diet, and blood analysis, glucose tolerance test and insulin tolerance test were performed. Also, skeletal muscle metabolism and gene expression including nucleotide levels and activation of AMP activated protein kinase (AMP kinase) were evaluated in both conditions. RESULTS: Disruption of the AMPD1 gene leads to a less severe state of insulin resistance, improved glucose tolerance and enhanced insulin clearance in mice fed a high fat diet. Given the central role of AMP kinase in insulin action, and its response to changes in AMP concentrations in the cell, we examined the skeletal muscle of the AMPD1 deficient mice and found that they have greater AMP kinase activity as evidenced by higher levels of phosphorylated AMP kinase. CONCLUSIONS: Taken together these data suggest that AMPD may be a new drug target for the reversal of insulin resistance and the treatment of Type II diabetes.

Interleukin 27 inhibits atherosclerosis via immunoregulation of macrophages in mice.

Chronic inflammation in arterial wall that is driven by immune cells and cytokines plays pivotal roles in the development of atherosclerosis. Interleukin 27 (IL-27) is a member of the IL-12 family of cytokines that consists of IL-27p28 and Epstein-Barr virus induced gene 3 (EBI3) and has anti-inflammatory properties that regulate T cell polarization and cytokine production. IL-27-deficient (Ldlr-/-Ebi3-/-) and IL-27 receptor-deficient (Ldlr-/-WSX-1-/-) Ldlr-/- mice were generated and fed with a high-cholesterol diet to induce atherosclerosis. Roles of bone marrow-derived cells in vivo and macrophages in vitro were studied using bone marrow reconstitution by transplantation and cultured peritoneal macrophages, respectively. We demonstrate that mice lacking IL-27 or IL-27 receptor are more susceptible to atherosclerosis compared with wild type due to enhanced accumulation and activation of macrophages in arterial walls. The number of circulating proinflammatory Ly6C(hi) monocytes showed no significant difference between wild-type mice and mice lacking IL-27 or IL-27 receptor. Administration of IL-27 suppressed the development of atherosclerosis in vivo and macrophage activation in vitro that was indicated by increased uptake of modified low-density lipoprotein and augmented production of proinflammatory cytokines. These findings define a novel inhibitory role for IL-27 in atherosclerosis that regulates macrophage activation in mice.

Detection of early stage atherosclerotic plaques using PET and CT fusion imaging targeting P-selectin in low density lipoprotein receptor-deficient mice.

BACKGROUND: Sensitive detection and qualitative analysis of atherosclerotic plaques are in high demand in cardiovascular clinical settings. The leukocyte-endothelial interaction mediated by an adhesion molecule P-selectin participates in arterial wall inflammation and atherosclerosis. METHODS AND RESULTS: A (64)Cu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid conjugated anti-P-selectin monoclonal antibody ((64)Cu-DOTA-anti-P-selectin mAb) probe was prepared by conjugating an anti-P-selectin monoclonal antibody with DOTA followed by (64)Cu labeling. Thirty-six hours prior to PET and CT fusion imaging, 3MBq of (64)Cu-DOTA-anti-P-selectin mAb was intravenously injected into low density lipoprotein receptor-deficient Ldlr-/- mice. After a 180min PET scan, autoradiography and biodistribution of (64)Cu-DOTA-anti-P-selectin monoclonal antibody was examined using excised aortas. In Ldlr-/- mice fed with a high cholesterol diet for promotion of atherosclerotic plaque development, PET and CT fusion imaging revealed selective and prominent accumulation of the probe in the aortic root. Autoradiography of aortas that demonstrated probe uptake into atherosclerotic plaques was confirmed by Oil red O staining for lipid droplets. In Ldlr-/- mice fed with a chow diet to develop mild atherosclerotic plaques, probe accumulation was barely detectable in the aortic root on PET and CT fusion imaging. Probe biodistribution in aortas was 6.6-fold higher in Ldlr-/- mice fed with a high cholesterol diet than in those fed with a normal chow diet. (64)Cu-DOTA-anti-P-selectin mAb accumulated selectively in aortic atherosclerotic plaques and was detectable by PET and CT fusion imaging in Ldlr-/- mice. CONCLUSIONS: P-selectin is a candidate target molecule for early-phase detection by PET and CT fusion imaging of atherosclerotic plaques.

The glucagon-like peptide 1 analog liraglutide reduces TNF-α-induced oxidative stress and inflammation in endothelial cells.

OBJECTIVE: Glucagon-like peptide 1 (GLP-1), one of the incretin hormones, has been reported to increase positive inotropic activity in cardiac myocytes and protect against myocardial injury. However, the effects upon endothelial cells and the mechanisms involved are not fully understood. We assessed the hypothesis that GLP-1 has protective effects against inflammation and oxidative stress on human endothelial cells. METHODS AND RESULTS: The effects of the GLP-1 analog liraglutide upon TNF-α-induced injury of the human umbilical vein endothelial cells (HUVECs) were evaluated. First, ROS induced by TNF-α was measured by staining with CM-H(2)DCFDA. Intracellular ROS production of HUVECs was significantly decreased in a dose-dependent manner until 30 nM while liraglutide inhibited the induction of gp91(phox) and p22(phox), subunit of NADPH oxidase, by TNF-α. In addition, protein levels of SOD-2, catalase and GPx were significantly increased by liraglutide. Second, rapid translocation of PKC-α into the membrane following TNF-α was evident. Liraglutide significantly inhibited this very rapid TNF-α-induced translocation of PKC-α into membrane at 2.5 min. Third, liraglutide significantly inhibited NF-κB activation and upregulated I-κB family while phosphorylation of IKK-α/ß, which is upstream of NF-κB signaling, was also downregulated after 15 min of TNF-α treatment. Finally, liraglutide inhibited apoptosis of HUVEC and expression of Pentraxin-3 induced by TNF-α. CONCLUSION: Liraglutide exerts marked anti-oxidative and anti-inflammatory effects on endothelial cells with inhibition of PKC-α, NADPH oxidase, NF-κB signaling and upregulation of protective anti-oxidative enzymes.

Endothelial dysfunction as a cellular mechanism for vascular failure.

The regulation of vascular tone, vascular permeability, and thromboresistance is essential to maintain blood circulation and therefore tissue environments under physiological conditions. Atherogenic stimuli, including diabetes, dyslipidemia, and oxidative stress, induce vascular dysfunction, leading to atherosclerosis, which is a key pathological basis for cardiovascular diseases such as ischemic heart disease and stroke. We have proposed a novel concept termed "vascular failure" to comprehensively recognize the vascular dysfunction that contributes to the development of cardiovascular diseases. Vascular endothelial cells form the vascular endothelium as a monolayer that covers the vascular lumen and serves as an interface between circulating blood and immune cells. Endothelial cells regulate vascular function in collaboration with smooth muscle cells. Endothelial dysfunction under pathophysiological conditions contributes to the development of vascular dysfunction. Here, we address the barrier function and microtubule function of endothelial cells. Endothelial barrier function, mediated by cell-to-cell junctions between endothelial cells, is regulated by small GTPases and kinases. Microtubule function, regulated by the acetylation of tubulin, a component of the microtubules, is a target of atherogenic stimuli. The elucidation of the molecular mechanisms of endothelial dysfunction as a cellular mechanism for vascular failure could provide novel therapeutic targets of cardiovascular diseases.

IL-27 inhibits hyperglycemia and pancreatic islet inflammation induced by streptozotocin in mice.

Inflammation driven by immune cells and pro-inflammatory cytokines is implicated in pancreatic ß-cell injury, leading to the development of diabetes mellitus. IL-27, a cytokine consisting of IL-27p28 and Epstein-Barr virus-induced gene 3 (EBI3), binds a membrane-bound heterodimeric receptor consisting of the IL-27 receptor α chain (WSX-1) and gp130. IL-27 has anti-inflammatory properties that regulate T-cell polarization and cytokine production. We evaluated blood glucose and islet proinsulin concentrations, inflammatory cell infiltration in islets, and expression of IL-1ß mRNA in pancreas in wild-type (WT), EBI3(-/-), and WSX-1(-/-) mice treated with streptozotocin (STZ). Hyperglycemia was augmented in EBI3(-/-) and WSX-1(-/-) mice compared with WT mice. Islet proinsulin levels after STZ treatment were lower in EBI3(-/-) and WSX-1(-/-) mice than in WT mice. The infiltration of islets by F4/80(+)CD11c(-)7/4(-) macrophages, CD4(+) T cells, and CD8(+) T cells was increased in EBI3(-/-) and WSX-1(-/-) mice compared with WT mice. The administration of recombinant IL-27, compared with control, decreased the blood glucose level, immune cell infiltration into islets, and IL-1ß mRNA expression in the pancreas and increased islet proinsulin levels in WT and EBI3(-/-) mice. Thus, IL-27 inhibits STZ-induced hyperglycemia and pancreatic islet inflammation in mice and represents a potential novel therapeutic approach for ß-cell protection in diabetes.