Efficacy and safety of pemafibrate in patients with hypertriglyceridemia in clinical settings: A retrospective study.

BACKGROUND AND AIMS: Recently, pemafibrate, a selective PPARα modulator, has been developed as a treatment for hypertriglyceridemia and has attracted much attention. The aims of this study were to evaluate the efficacy and safety of pemafibrate in hypertriglyceridemia patients under clinical settings. METHODS AND RESULTS: We evaluated changes in lipid profiles and various parameters before and after 24-week pemafibrate administration in patients with hypertriglyceridemia who had not previously taken fibrate medications. There were 79 cases included in the analysis. 24 weeks after the treatment with pemafibrate, TG was significantly reduced from 312 ± 226 to 167 ± 94 mg/dL. In addition, lipoprotein fractionation tests using PAGE method showed a significant decrease in the ratio of VLDL and remnant fractionations, which are TG-rich lipoproteins. After pemafibrate administration, body weight, HbA1c, eGFR, and CK levels were not changed, but liver injury indices such as ALT, AST, and γ-GTP were significantly improved. CONCLUSION: In this study, pemafibrate improved the metabolism of atherosclerosis-induced lipoproteins in hypertriglyceridemia patients. In addition, it showed no off-target effects such as hepatic and renal damage or rhabdomyolysis.

Multiple endocrine neoplasia type 1 with a frameshift mutation in its gene accompanied by a giant cervical lipoma and multiple fatty deposits in the pancreas: case report.

BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a syndrome characterized by pituitary neoplasia, primary hyperparathyroidism and pancreatic endocrine tumor. Here we show a case of MEN1 with a germline frameshift mutation in its gene accompanied by a giant cervical lipoma and multiple fatty deposits in the pancreas. CASE PRESENTATION: A 28-year-old man noticed the decreased visual acuity of both eyes and visited our institution. Since he was diagnosed as visual disturbance and brain computer tomography (CT) showed a mass in the pituitary fossa, he was hospitalized in our institution. Endoscopic trans-sphenoidal hypophysectomy and total parathyroidectomy with auto-transplantation were performed, and a giant cervical lipoma was resected. Furthermore, in genetic search, we found a germline frameshift mutation in MEN1 gene leading to the appearance of a new stop codon. CONCLUSIONS: We should bear in m ind that giant skin lipoma and multiple abnormal fatty deposits in the pancreas could be complicated with MEN1.

A case of tamoxifen-induced hypertriglyceridemia monitoring the changes in lipoprotein fractions over time.

BACKGROUND: Tamoxifen, which is one of the selective estrogen receptor modulators (SERMs), can bring out life-threatening complication, e.g. hypertriglyceridemia-induced acute pancreatitis, although it is rare. We precisely report changes in lipoprotein metabolism before and after tamoxifen discontinuation because there have been few reports of it. CASE PRESENTATION: 47-year-old premenopausal woman with dyslipidemia, type 2 diabetes, nonalcoholic fatty liver disease and chronic kidney disease was prescribed tamoxifen as adjuvant therapy after operation of breast cancer. She experienced severe tamoxifen-induced hypertriglyceridemia several months after dosing tamoxifen. Before cessation of tamoxifen, lipoprotein fraction test revealed marked stagnation of VLDL and IDL metabolisms, resulting in severe hypertriglyceridemia (serum triglyceride level was 1881 mg/dL). Seven days after tamoxifen withdrawal, lipoprotein fraction test showed that the metabolisms of endogenous lipoproteins were changed drastically. CONCLUSIONS: From these results, we confirmed that tamoxifen certainly changes lipoprotein metabolism through suppression of post-heparin lipolytic activity. It is very important to evaluate the balance between benefit and risk before dosing tamoxifen and survey lipid profiles constantly during treatment to avoid life-threatening complication when prescription of tamoxifen is planned.

Efficacy and safety of adding ipragliflozin to insulin in Japanese patients with type 1 diabetes mellitus: a retrospective study.

Advances in insulin preparations and administration methods have produced a gradual improvement in glycemic control in patients with type 1 diabetes mellitus (DM). Nevertheless, glycated hemoglobin (HbA1c) levels in patients with type 1 DM are still poor compared to those in patients with type 2 DM. Here, we sought to assess the efficacy and safety of the sodium-glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin (IPRA) in patients with type 1 DM. This study was retrospectively conducted with data from type 1 DM patients who had a history of IPRA therapy. The primary endpoint was HbA1c level at 24 weeks. The baseline characteristics of a total of 12 subjects were as follows: age, 50.1 ± 13.2 years; diabetes duration, 17.3 ± 10.5 years; body mass index (BMI), 22.9 ± 2.1 kg/m2; HbA1c, 8.8 ± 1.3%; and daily insulin dose, 0.60 ± 0.21 units/kg. IPRA decreased HbA1c levels to 8.2 ± 1.2% (p < 0.05) and reduced insulin dose to 0.52 ± 0.17 units/kg (p < 0.01) after 24 weeks. HbA1c value was particularly reduced in subjects with preserved C-peptide index. IPRA significantly reduced body weight by -1.4 ± 1.4 kg (p < 0.01) 16 weeks after starting treatment, with no further weight loss after 24 weeks. There were no instances of diabetic ketoacidosis or severe hypoglycemia. IPRA exerted beneficial effects on glycemic control without any severe adverse effects, and should be safe and effective when used in patients with type 1 DM with understanding of correspondence in sick day.

Multifaceted Mechanisms of Action of Metformin Which Have Been Unraveled One after Another in the Long History.

While there are various kinds of drugs for type 2 diabetes mellitus at present, in this review article, we focus on metformin which is an insulin sensitizer and is often used as a first-choice drug worldwide. Metformin mainly activates adenosine monophosphate-activated protein kinase (AMPK) in the liver which leads to suppression of fatty acid synthesis and gluconeogenesis. Metformin activates AMPK in skeletal muscle as well, which increases translocation of glucose transporter 4 to the cell membrane and thereby increases glucose uptake. Further, metformin suppresses glucagon signaling in the liver by suppressing adenylate cyclase which leads to suppression of gluconeogenesis. In addition, metformin reduces autophagy failure observed in pancreatic ß-cells under diabetic conditions. Furthermore, it is known that metformin alters the gut microbiome and facilitates the transport of glucose from the circulation into excrement. It is also known that metformin reduces food intake and lowers body weight by increasing circulating levels of the peptide hormone growth/differentiation factor 15 (GDF15). Furthermore, much attention has been drawn to the fact that the frequency of various cancers is lower in subjects taking metformin. Metformin suppresses the mechanistic target of rapamycin (mTOR) by activating AMPK in pre-neoplastic cells, which leads to suppression of cell growth and an increase in apoptosis in pre-neoplastic cells. It has been shown recently that metformin consumption potentially influences the mortality in patients with type 2 diabetes mellitus and coronavirus infectious disease (COVID-19). Taken together, metformin is an old drug, but multifaceted mechanisms of action of metformin have been unraveled one after another in its long history.

Unexpected Pleiotropic Effects of SGLT2 Inhibitors: Pearls and Pitfalls of This Novel Antidiabetic Class.

Sodium-glucose co-transporter 2 (SGLT2) inhibitors facilitate urine glucose excretion by reducing glucose reabsorption, leading to ameliorate glycemic control. While the main characteristics of type 2 diabetes mellitus are insufficient insulin secretion and insulin resistance, SGLT2 inhibitors have some favorable effects on pancreatic ß-cell function and insulin sensitivity. SGLT2 inhibitors ameliorate fatty liver and reduce visceral fat mass. Furthermore, it has been noted that SGLT2 inhibitors have cardio-protective and renal protective effects in addition to their glucose-lowering effect. In addition, several kinds of SGLT2 inhibitors are used in patients with type 1 diabetes mellitus as an adjuvant therapy to insulin. Taken together, SGLT2 inhibitors have amazing multifaceted effects that are far beyond prediction like some emerging magical medicine. Thereby, SGLT2 inhibitors are very promising as relatively new anti-diabetic drugs and are being paid attention in various aspects. It is noted, however, that SGLT2 inhibitors have several side effects such as urinary tract infection or genital infection. In addition, we should bear in mind the possibility of diabetic ketoacidosis, especially when we use SGLT2 inhibitors in patients with poor insulin secretory capacity.

Favorable Effects of GLP-1 Receptor Agonist against Pancreatic ß-Cell Glucose Toxicity and the Development of Arteriosclerosis: "The Earlier, the Better" in Therapy with Incretin-Based Medicine.

Fundamental pancreatic ß-cell function is to produce and secrete insulin in response to blood glucose levels. However, when ß-cells are chronically exposed to hyperglycemia in type 2 diabetes mellitus (T2DM), insulin biosynthesis and secretion are decreased together with reduced expression of insulin transcription factors. Glucagon-like peptide-1 (GLP-1) plays a crucial role in pancreatic ß-cells; GLP-1 binds to the GLP-1 receptor (GLP-1R) in the ß-cell membrane and thereby enhances insulin secretion, suppresses apoptotic cell death and increase proliferation of ß-cells. However, GLP-1R expression in ß-cells is reduced under diabetic conditions and thus the GLP-1R activator (GLP-1RA) shows more favorable effects on ß-cells at an early stage of T2DM compared to an advanced stage. On the other hand, it has been drawing much attention to the idea that GLP-1 signaling is important in arterial cells; GLP-1 increases nitric oxide, which leads to facilitation of vascular relaxation and suppression of arteriosclerosis. However, GLP-1R expression in arterial cells is also reduced under diabetic conditions and thus GLP-1RA shows more protective effects on arteriosclerosis at an early stage of T2DM. Furthermore, it has been reported recently that administration of GLP-1RA leads to the reduction of cardiovascular events in various large-scale clinical trials. Therefore, we think that it would be better to start GLP-1RA at an early stage of T2DM for the prevention of arteriosclerosis and protection of ß-cells against glucose toxicity in routine medical care.

Notable Underlying Mechanism for Pancreatic ß-Cell Dysfunction and Atherosclerosis: Pleiotropic Roles of Incretin and Insulin Signaling.

Under healthy conditions, pancreatic ß-cells produce and secrete the insulin hormone in response to blood glucose levels. Under diabetic conditions, however, ß-cells are compelled to continuously secrete larger amounts of insulin to reduce blood glucose levels, and thereby, the ß-cell function is debilitated in the long run. In the diabetic state, expression levels of insulin gene transcription factors and incretin receptors are downregulated, which we think is closely associated with ß-cell failure. These data also suggest that it would be better to use incretin-based drugs at an early stage of diabetes when incretin receptor expression is preserved. Indeed, it was shown that incretin-based drugs exerted more protective effects on ß-cells at an early stage. Furthermore, it was shown recently that endothelial cell dysfunction was also associated with pancreatic ß-cell dysfunction. After ablation of insulin signaling in endothelial cells, the ß-cell function and mass were substantially reduced, which was also accompanied by reduced expression of insulin gene transcription factors and incretin receptors in ß-cells. On the other hand, it has been drawing much attention that incretin plays a protective role against the development of atherosclerosis. Many basic and clinical data have underscored the importance of incretin in arteries. Furthermore, it was shown recently that incretin receptor expression was downregulated in arteries under diabetic conditions, which likely diminishes the protective effects of incretin against atherosclerosis. Furthermore, a series of large-scale clinical trials (SPAED-A, SPIKE, LEADER, SUSTAIN-6, REWIND, PIONEER trials) have shown that various incretin-related drugs have beneficial effects against atherosclerosis and subsequent cardiovascular events. These data strengthen the hypothesis that incretin plays an important role in the arteries of humans, as well as rodents.

Correction to: Vascular endothelial PDPK1 plays a pivotal role in the maintenance of pancreatic beta cell mass and function in adult male mice.

It has been brought to our attention that Fig. 5a showing the vasculature in islets of control flox mice is not in fact an endocrine cell but rather exocrine tissue.

Vascular endothelial PDPK1 plays a pivotal role in the maintenance of pancreatic beta cell mass and function in adult male mice.

AIMS/HYPOTHESIS: The aim of this study was to elucidate the impact of 3'-phosphoinositide-dependent protein kinase-1 (PDPK1) in vascular endothelial cells on the maintenance of pancreatic beta cell mass and function. METHODS: Male vascular endothelial cell-specific Pdpk1-knockout mice (Tie2+/-/Pdpk1flox/flox mice) and their wild-type littermates (Tie2-/-/Pdpk1flox/flox mice; control) were used for this study. At 12 weeks of age, an IPGTT and OGTT were conducted. Pancreatic blood flow was measured under anaesthesia. Thereafter, islet blood flow was measured by the microsphere method. Mice were killed for islet isolation and further functional study and mRNA was extracted from islets. Pancreases were sampled for immunohistochemical analyses. RESULTS: During the IPGTT, the blood glucose level was comparable between knockout mice and control flox mice, although serum insulin level was significantly lower in knockout mice. During the OGTT, glucose tolerance deteriorated slightly in knockout mice, accompanied by a decreased serum insulin level. During an IPGTT after pre-treatment with exendin-4 (Ex-4), glucose tolerance was significantly impaired in knockout mice. In fact, glucose-stimulated insulin secretion of isolated islets from knockout mice was significantly reduced compared with control flox mice, and addition of Ex-4 revealed impaired sensitivity to incretin hormones in islets of knockout mice. In immunohistochemical analyses, both alpha and beta cell masses were significantly reduced in knockout mice. In addition, the CD31-positive area was significantly decreased in islets of knockout mice. The proportion of pimonidazole-positive islets was significantly increased in knockout mice. mRNA expression levels related to insulin biosynthesis (Ins1, Ins2, Mafa, Pdx1 and Neurod [also known as Neurod1]) and beta cell function (such as Gck and Slc2a2) were significantly decreased in islets of knockout mice. Microsphere experiments revealed remarkably reduced islet blood flow. In addition, mRNA expression levels of Hif1α (also known as Hif1a) and its downstream factors such as Adm, Eno1, Tpi1 (also known as Ets1), Hmox1 and Vegfa, were significantly increased in islets of knockout mice, indicating that islets of knockout mice were in a more hypoxic state than those of control flox mice. As a result, mRNA expression levels related to adaptive unfolded protein response and endoplasmic reticulum stress-related apoptotic genes were significantly elevated in islets of knockout mice. In addition, inflammatory cytokine levels were increased in islets of knockout mice. Electron microscopy revealed reduced endothelial fenestration and thickening of basal membrane of vascular endothelium in islets of knockout mice. CONCLUSIONS/INTERPRETATION: Vascular endothelial PDPK1 plays an important role in the maintenance of pancreatic beta cell mass and function by maintaining vascularity of pancreas and islets and protecting them from hypoxia, hypoxia-related endoplasmic reticulum stress, inflammation and distortion of capillary structure.

Eicosapentaenoic acid/arachidonic acid ratio and weight loss during hospitalization for glycemic control among overweight Japanese patients with type 2 diabetes: a retrospective observational study.

BACKGROUND: The study aimed to examine the relationship between levels of serum eicosapentaenoic acid (EPA), arachidonic acid (AA), as well as EPA/AA ratio and weight loss during hospitalization in participants considered to be overweight, with type 2 diabetes. METHODS: The study participants included 142 patients who were hospitalized for treatment of type 2 diabetes. We divided the participants into two groups depending on the achievenemt in reduction of bodyweight 3% or more during hospitalization and examined the relationship between serum levels of EPA and AA, as well as ratio of EPA/AA on admission and effectiveness of weight loss under strict dietary therapy during hospitalization, using Cox proportional hazard models. RESULTS: After adjustment was made for several confounders, the hazard ratio of effective weight loss for logarithmical serum EPA was 1.59 (95% CI 1.02-2.49, P = 0.04) and for logarithmical EPA/AA ratio 1.64 (1.03-2.61, P = 0.04), whereas the hazard ratio for effective weight loss for logarithmical serum AA was 1.11 (0.45-2.78, P = 0.82). In addition, after dividing EPA/AA ratio and serum EPA into quartiles based on participant number, the hazard ratio for the highest quartile of EPA/AA ratio was 2.33 (1.14-4.77, P = 0.02), and for the highest quartile of serum EPA 1.60 (0.80-3.19, P = 0.18) compared with the lowest quartile. CONCLUSION: These results suggest the possibility that EPA is involved in bodyweight change under a caloric-restriction regimen. In addition, EPA/AA ratio was found to be a better predictor of medical intervention for weight loss among overweight patients with type 2 diabetes, compared with serum EPA level.

Suppression of free fatty acid receptor 1 expression in pancreatic ß-cells in obese type 2 diabetic db/db mice: a potential role of pancreatic and duodenal homeobox factor 1.

It is known that long-chain fatty acids bind to free fatty acid receptor 1 (Ffar1), also known as G protein-coupled receptor 40 (GPR40), and amplify glucose-stimulated insulin secretion (GSIS) from pancreatic ß-cells and that Ffar1 agonists facilitates insulin secretion and ameliorates glycemic control. On the other hands, pancreatic and duodenal homeobox factor 1 (Pdx1) is an important transcription factor for various ß-cell-related genes including insulin gene and thereby contributes to the maintenance of mature ß-cell function. The aim of this study was to evaluate how Ffar1 expression in ß-cells is altered under diabetic conditions. In this study, we used male obese type 2 diabetic mice and control mice. We evaluated Ffar1 and Pdx1 mRNA and protein expression levels in both mice. In addition, we examined whether Pdx1 is a possible regulator of Ffar1 expression using small interfering RNA for Pdx1 (siPdx1) in ß-cell-derived cell line. As the results, Ffar1 mRNA and protein expression in ß-cells were significantly lower in obese type 2 diabetic db/db mice compared to control mice which was accompanied by the decreased expression of Pdx1. In addition, down-regulation of Pdx1 expression using siPdx1 suppressed Ffar1 expression. Furthermore, adenoviral Pdx1 overexpression significantly increased Ffar1 expression. In conclusion, Ffar1 expression is markedly down-regulated under diabetic conditions which is accompanied by decreased expression of Pdx1. Furthermore, it is likely that Pdx1 is a regulator of Ffar1 expression in ß-cells.

Protective effects of the SGLT2 inhibitor luseogliflozin on pancreatic ß-cells in db/db mice: The earlier and longer, the better.

AIMS: We compared the protective effects of sodium glucose co-transporter (SGLT) 2 inhibitor luseogliflozin on pancreatic ß-cells between early and advanced stages of diabetes and between short- and long-term use. MATERIALS AND METHODS: Diabetic db/db mice were treated with luseogliflozin for 2 weeks in an early stage of diabetes (7-9 weeks of age) and an advanced stage of diabetes (16-18 weeks) for a longer period of time (7-18 weeks). We performed various morphological analyses of pancreatic islets and examined gene expression profiles in islets after such treatment. RESULTS: In diabetic db/db mice, insulin biosynthesis and secretion were markedly increased by luseogliflozin in an early stage of diabetes but not in an advanced stage. In addition, ß-cell mass was preserved by luseogliflozin only in an early stage. Furthermore, when db/db mice were treated with luseogliflozin for a longer period of time, starting from an early stage, ß-cell function and mass were markedly preserved even after a longer period of time compared to untreated db/db mice. CONCLUSION: Luseogliflozin exerts more protective effects in an early stage of diabetes compared to an advanced stage, and longer-term use of luseogliflozin exerts more beneficial effects on pancreatic ß-cells compared to short-term use.

Protective effects of SGLT2 inhibitor luseogliflozin on pancreatic ß-cells in obese type 2 diabetic db/db mice.

It is well known that Sodium-Glucose Co-transporter 2 (SGLT2) inhibitors, new hypoglycemic agents, improve glycemic control by increasing urine glucose excretion, but it remained unclear how they exert protective effects on pancreatic ß-cells. In this study, we examined the effects of SGLT2 inhibitor luseogliflozin on ß-cell function and mass using obese type 2 diabetic db/db mice. Ten-week-old male diabetic db/db mice were treated with luseogliflozin 0.0025% or 0.01% in chow (Luse 0.0025% or Luse 0.01%) or vehicle (control) for 4 weeks. Urinary glucose excretion was increased in Luse groups (0.0025% and 0.01%) compared to control mice 3 days after the intervention. Fasting blood glucose levels were significantly lower in mice treated with Luse compared to control mice. Fasting serum insulin concentrations were significantly higher in mice treated with Luse compared to control mice. Triglyceride levels tended to be lower in Luse groups compared to control mice. In immunohistochemical study using pancreas tissues, ß-cell mass was larger in Luse groups compared to control group which was due to the increase of ß-cell proliferation and decrease of ß-cell apoptosis. Furthermore, in gene analysis using isolated islets, insulin 1, insulin 2, MafA, PDX-1 and GLUT2 gene expression levels were significantly higher in Luse groups compared to control group. In contrast, expression levels of fibrosis-related gene such as TGFß, fibronectin, collagen I and collagen III were significantly lower in Luse groups. In conclusion, SGLT2 inhibitor luseogliflozin ameliorates glycemic control and thus exerts protective effects on pancreatic ß-cell mass and function.

Chelation-Assisted Nickel-Catalyzed Oxidative Annulation via Double C-H Activation/Alkyne Insertion Reaction.

A nickel/NHC system for regioselective oxidative annulation by double C-H bond activation and concomitant alkyne insertion is described. The catalytic reaction requires a bidentate directing group, such as an 8-aminoquinoline, embedded in the substrate. Various 5,6,7,8-tetrasubstituted-N-(quinolin-8-yl)-1-naphthamides can be prepared as well as phenanthrene and benzo[h]quinoline amide derivatives. Diarylalkynes, dialkylalkynes, and arylalkylalkynes can be used in the system. A Ni(0)/Ni(II) catalytic cycle is proposed as the main catalytic cycle. The alkyne plays a double role as a two-component coupling partner and as a hydrogen acceptor.

Time Course of Diffusion Kurtosis in Cerebral Infarctions of Transient Middle Cerebral Artery Occlusion Rat Model.

OBJECTIVE: To evaluate the relationship between fiber bundle direction and changes in diffusion kurtosis, we evaluated the apparent diffusion kurtosis coefficients (AKCs) that were perpendicular to and parallel to the principal diffusion tensor eigenvector. MATERIALS AND METHODS: Adult male Wistar rats were subjected to 30 or 60 minutes of middle cerebral artery occlusion and imaged with a 7T Magnetic Resonance Imager System (Varian MRI System 7T/210: Agilent Technologies, CA). Diffusion kurtosis images were obtained before middle cerebral artery (MCA) reperfusion and 3, 6, and 24 hours after reperfusion to generate the apparent diffusion coefficient (ADC), fractional anisotropy (FA), mean apparent diffusion kurtosis coefficient (mAKC), AKC axial to the eigenvector (axAKC), and AKC radial to the eigenvector (radAKC) images. The time course of the region/normal ratio was evaluated for the above parameters in the caudoputamen and white matter. RESULTS: Relative FA and relative ADC values decreased 3 hours after MCA reperfusion and remained decreased until 24 hours. Relative mAKC, axAKC, and radAKC values were increased 3 hours after MCA reperfusion, peaked after 6 hours, and slightly decreased after 24 hours. In the white matter, axAKC showed larger changes than radAKC. CONCLUSION: The time course of the diffusion kurtosis value showed earlier pseudonormalization than the ADC value of the lesions. For white matter lesions, the increase in axAKC was larger than that in radAKC, suggesting that the tissue changes after infarction mainly produce reduced diffusivity along the fibers and lead to increased inhomogeneity of the diffusion.

Pharmacological MRI response to a selective dopamine transporter inhibitor, GBR12909, in awake and anesthetized rats.

Pharmacological magnetic resonance imaging (phMRI) is a powerful tool for imaging the effects of drugs on brain activity. In preclinical phMRI studies, general anesthesia used for minimizing head movements is thought to influence the phMRI responses to drugs. In this study we investigated the phMRI responses to a selective dopamine transporter (DAT) inhibitor, GBR12909, and a dopamine (DA) releaser, d-amphetamine (AMPH), in the isoflurane anesthetized and awake rats using a relative cerebral blood volume (rCBV) method. AMPH (1 mg/kg i.p.) caused an increase in rCBV in the dopaminergic circuitry in the both anesthetized and awake rats. The striatal rCBV change was correlated with the change of the striatal DA concentration induced by AMPH in the both anesthetized and awake rats. GBR12909 (10 mg/kg i.p.) caused a positive rCBV response and showed a similar regional pattern of rCBV response to AMPH in the awake rats, and the correlation between the change of the striatal rCBV and the striatal DA concentration was observed. However, in the anesthetized rats, GBR12909 induced a widespread negative rCBV response, whereas an increase in striatal DA concentration was observed. These findings indicate that phMRI responses to activation of DA neurotransmission by GBR12909 or AMPH are overall identical in the awake state, while the phMRI response to a DAT inhibitor, GBR12909 but not to AMPH was changed by isoflurane anesthesia. For the evaluation of neuroactive drugs using phMRI, isoflurane anesthesia might be complicated the interpretation of pharmacodynamic effects of drugs in preclinical studies.

Anti-hypertensive azelnidipine preserves insulin signaling and glucose uptake against oxidative stress in 3T3-L1 adipocytes.

It is known that reactive oxygen species (ROS) are involved in the development of insulin resistance as well as pancreatic ß-cell dysfunction both of which are often observed in type 2 diabetes. In this study, we evaluated the effects of azelnidipine, a calcium channel blocker, on ROS-mediated insulin resistance in adipocytes. When 3T3-L1 adipocytes were exposed to ROS, insulin-mediated glucose uptake was suppressed, but such phenomena were not observed in the presence of azelnidipine. Phosphorylation of insulin receptor and phosphorylation of Akt were suppressed by ROS, which was mitigated by azelnidipine treatment. Activation of the JNK pathway induced by ROS was also reduced by azelnidipine. Various inflammatory cytokine levels were increased by ROS, which was also suppressed by azelnidipine treatment. In contrast, adiponectin mRNA and secreted adiponectin levels were reduced by ROS, which was refilled by azelnidipine treatment. In conclusion, azelnidipine preserves insulin signaling and glucose uptake against oxidative stress in 3T3-L1 adipocytes.

TCF7L2 in mouse pancreatic beta cells plays a crucial role in glucose homeostasis by regulating beta cell mass.

AIMS/HYPOTHESIS: Common genetic variations of the transcription factor 7-like 2 gene (encoded by TCF7L2), one of the T cell factor/lymphoid enhancer-binding factor transcription factors for the converging wingless-type MMTV integration site family (Wnt)/ß-catenin signalling pathway, are known to be associated with type 2 diabetes. Individuals with at-risk alleles of TCF7L2 exhibit impaired insulin secretion. Although previous studies using animal models have revealed the existence of a relationship between the Wnt/ß-catenin signalling pathway and glucose homeostasis, it remains unclear whether TCF7L2 in the pancreatic beta cells might be causally involved in insulin secretion in vivo. In this study, we investigated the role of TCF7L2 expressed in the pancreatic beta cells in glucose homeostasis. METHODS: Three independent groups of genetically engineered mice (DN mice) were generated, in which expression of the dominant-negative form of Tcf7l2 was driven under a rat insulin promoter. Phenotypes of both adult and newborn mice were evaluated. The levels of genes and proteins expressed in isolated islets were determined by reverse transcription-quantitative PCR and western blot analysis, respectively. RESULTS: Adult DN mice showed impaired glucose tolerance and decreased insulin secretion in both oral and intraperitoneal glucose tolerance tests. Marked reduction of the beta cell area and whole-pancreas insulin content was observed in both the adult and newborn DN mice. Islets from the DN mice showed decreased gene expressions of Ccnd1, Ccnd2, Irs1, Irs2, Ins1, Ins2 and Mafa, consistent with the deleterious effects of the dominant-negative form of Tcf7l2 on beta cell proliferation and insulin production. CONCLUSIONS/INTERPRETATION: TCF7L2 expressed in the pancreatic beta cells plays a crucial role in glucose metabolism through regulation of the beta cell mass.

Effect of the Great East Japan Earthquake on cardiovascular diseases--report from the 10 hospitals in the disaster area.

BACKGROUND: We reported an increased occurrence of cardiovascular diseases (CVDs) after the Great East Japan Earthquake by examining ambulance records, but it had to be confirmed by cardiologists. METHODS AND RESULTS: We enrolled patients admitted to the cardiology department of the 10 hospitals in the disaster area from 4 weeks prior to 15 weeks after March 11 in the years 2008-2011 (n=14,078). The weekly occurrence of several CVDs, including heart failure (HF), pulmonary thromboembolism (PTE) and infectious endocarditis (IE), was sharply and significantly increased after the Earthquake. CONCLUSIONS: The Disaster caused significantly increases in the occurrence of HF, PTE and IE.