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Plasma glycerol is a major substrate for hepatic gluconeogenesis. Aquaporin adipose (AQPap/7), an adipose-specific glycerol channel, provides fat-derived glycerol into plasma. In the present study, we cloned the coding and promoter regions of mouse aquaporin 9 (AQP9), a liver-specific glycerol channel. Fasting and refeeding of mice increased and decreased hepatic AQP9 mRNA levels, respectively. Insulin deficiency induced by streptozotocin resulted in increased hepatic AQP9 mRNA. These changes in hepatic AQP9 mRNA were accompanied by those of hepatic gluconeogenic mRNAs and plasma glycerol levels. In cultured hepatocytes, insulin downregulated AQP9 mRNA. The AQP9 promoter contained the negative insulin response element TGTTTTC at -496/-502, similar to the promoter of the AQPap/7 gene. In contrast, in insulin-resistant db+/db+ mice, AQPap/7 mRNA in fat and AQP9 mRNA in liver were increased, despite hyperinsulinemia, with high plasma glycerol and glucose levels. Glycerol infusion in the db+/db+ mice augmented hepatic glucose output. Our results indicate that coordinated regulations of fat-specific AQPap/7 and liver-specific AQP9 should be crucial to determine glucose metabolism in physiology and insulin resistance. [ABSTRACT FROM AUTHOR]

Adiponectin, an adipose-specific secretory protein, exhibits antidiabetic and antiatherogenic properties. In the present study, we examined the effects of sex hormones on the regulation of adiponectin production. Plasma adiponectin concentrations were significantly lower in 442 men (age, 52.6 +/- 11.9 years [mean +/- SD]) than in 137 women (53.2 +/- 12.0 years) but not different between pre- and postmenopausal women. In mice, ovariectomy did not alter plasma adiponectin levels. In contrast, high levels of plasma adiponectin were found in castrated mice. Testosterone treatment reduced plasma adiponectin concentration in both sham-operated and castrated mice. In 3T3-L1 adipocytes, testosterone reduced adiponectin secretion into the culture media, using pulse-chase study. Castration-induced increase in plasma adiponectin was associated with a significant improvement of insulin sensitivity. Our results indicate that androgens decrease plasma adiponectin and that androgen-induced hypoadiponectinemia may be related to the high risks of insulin resistance and atherosclerosis in men. [ABSTRACT FROM AUTHOR]

Adiponectin, also referred to as AdipoQ or ACRP30, is a plasma protein produced and secreted exclusively from adipose tissue. The protein contains a collagen-like domain and a C1q-like globular domain. A protease-generated globular segment enhances fatty acid oxidation in muscles, thereby modulating lipid and glucose metabolism. Plasma adiponectin levels are inversely correlated with the severity of insulin resistance. A recent genome-wide scan study mapped a susceptibility locus for type 2 diabetes and the metabolic syndrome to chromosome 3q27, where the adiponectin gene is located. Here, we screened Japanese patients with type 2 diabetes and age- and BMI-matched nondiabetic control subjects for mutations in adiponectin gene. We identified four missense mutations (R112C, I164T, R221S, and H241P) in the globular domain. Among these mutations, the frequency of I164T mutation was significantly higher in type 2 diabetic patients than in age- and BMI- matched control subjects (P < 0.01). Furthermore, plasma adiponectin concentrations of subjects carrying I164T mutation were lower than those of subjects without the mutation. All the subjects carrying I164T mutation showed some feature of metabolic syndrome, including hypertension, hyperlipidemia, diabetes, and atherosclerosis. Our findings suggest that I164T mutation is associated with low plasma adiponectin concentration and type 2 diabetes. [ABSTRACT FROM AUTHOR]

The mechanism by which the obese subjects are more associated with vascular disease remains unclear. We reported that the adipose tissues produce and secrete many bioactive molecules, conceptualized as adipocytokines. Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), produced locally by vascular macrophages and smooth muscle cells, has been suggested to induce the migration and proliferation of vascular smooth muscle cells. The current study reveals that (1) HB-EGF mRNA is abundantly expressed in human adipose tissue, (2) HB-EGF mRNA increases in the fat tissues of obese mice, (3) plasma HB-EGF levels increase in parallel with fat accumulation in human, and (4) the subjects with coronary artery disease have higher plasma HB-EGF levels, associated with fat accumulation. These results suggest that increased plasma HB-EGF derived from the accumulated fat contributes to the higher incidence of vascular disease in obesity, proposing HB-EGF as an adipocytokine directly linking adipovascular axis. [Copyright &y& Elsevier]

Aquaporin adipose (AQPap), which we identified from human adipose tissue, is a glycerol channel in adipocyte [Kishida et al . (2000) J. Biol. Chem. 275 , 20896–20902]. In the current study, we determined the genomic structure of the human AQPap gene, and identified three AQPap-like genes that resembled (≈ 95%) AQPap, with little expression in human tissues. The AQPap promoter contained a putative peroxisome proliferator response element (PPRE) at -46 to -62, and a putative insulin response element (IRE) at -542/-536. Deletion of the PPRE abolished the pioglitazone-mediated induction of AQPap promoter activity in 3T3-L1 adipocytes. Deletion and single base pair substitution analysis of the IRE abolished the insulin-mediated suppression of the human AQPap gene. Analysis of AQPap sequence in human subjects revealed three missense mutations (R12C, V59L and G264V), and two silent mutations (A103A and G250G). The cRNA injection of the missense mutants into Xenopus oocytes revealed the absence of the activity to transport glycerol and water in the AQPap-G264V protein. In the subject homozygous for AQPap-G264V, exercise-induced increase in plasma glycerol was not observed in spite of the increased plasma noradrenaline. We suggest that AQPap is responsible for the increase of plasma glycerol during exercise in humans. [ABSTRACT FROM AUTHOR]

Insulin resistance and its dreaded consequence, type 2 diabetes, are major causes of atherosclerosis. Adiponectin is an adipose-specific plasma protein that possesses anti-atherogenic properties, such as the suppression of adhesion molecule expression in vascular endothelial cells and cytokine production from macrophages. Plasma adiponectin concentrations are decreased in obese and type 2 diabetic subjects with insulin resistance. A regimen that normalizes or increases the plasma adiponectin might prevent atherosclerosis in patients with insulin resistance. In this study, we demonstrate the inducing effects of thiazolidinediones (TZDs), which are synthetic PPARgamma ligands, on the expression and secretion of adiponectin in humans and rodents in vivo and in vitro. The administration of TZDs significantly increased the plasma adiponectin concentrations in insulin resistant humans and rodents without affecting their body weight. Adiponectin mRNA expression was normalized or increased by TZDs in the adipose tissues of obese mice. In cultured 3T3-L1 adipocytes, TZD derivatives enhanced the mRNA expression and secretion of adiponectin in a dose- and time-dependent manner. Furthermore, these effects were mediated through the activation of the promoter by the TZDs. On the other hand, TNF-alpha, which is produced more in an insulin-resistant condition, dose-dependently reduced the expression of adiponectin in adipocytes by suppressing its promoter activity. TZDs restored this inhibitory effect by TNF-alpha. TZDs might prevent atherosclerotic vascular disease in insulin-resistant patients by inducing the production of adiponectin through direct effect on its promoter and antagonizing the effect of TNF-alpha on the adiponectin promoter. [ABSTRACT FROM AUTHOR]

Examines on the characterization of the Clostridium perfringens enterotoxin (CPE) receptor gene cloned from an expression library of enterotoxin-sensitive Vero cells. Pretreatment of CPE-sensitive cells with neuraminidase; Release of intracellular molecules from sensitive cells; Molecular mechanism of the action of the CPE.

Background The impact of chronic kidney disease (CKD) on the prognostic utility of cardiovascular biomarkers in high-risk patients remains unclear. Methods and Results We performed a multicenter, prospective cohort study of 3255 patients with suspected or known coronary artery disease (CAD) to investigate whether CKD modifies the prognostic utility of cardiovascular biomarkers. Serum levels of cardiovascular and renal biomarkers, including soluble fms-like tyrosine kinase-1 (sFlt-1), N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin-I (hs-cTnI), cystatin C, and placental growth factor, were measured in 1301 CKD and 1954 patients without CKD. The urine albumin to creatinine ratio (UACR) was measured in patients with CKD. The primary outcome was 3-point MACE (3P-MACE) defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke. The secondary outcomes were all-cause death, cardiovascular death, and 5P-MACE defined as a composite of 3P-MACE, heart failure hospitalization, and coronary/peripheral artery revascularization. After adjustment for clinical confounders, sFlt-1, NT-proBNP, and hs-cTnI, but not other biomarkers, were significantly associated with 3P-MACE, all-cause death, and cardiovascular death in the entire cohort and in patients without CKD. These associations were still significant in CKD only for NT-proBNP and hs-cTnI. NT-proBNP and hs-cTnI were also significantly associated with 5P-MACE in CKD. The UACR was not significantly associated with any outcomes in CKD. NT-proBNP and hs-cTnI added incremental prognostic information for all outcomes to the model with potential clinical confounders in CKD. Conclusions NT-proBNP and hs-cTnI were the most powerful prognostic biomarkers in patients with suspected or known CAD and concomitant CKD.

Aims: Endothelial cell vascular endothelial growth factor receptor 2 (VEGFR-2) plays a pivotal role in angiogenesis, which induces physiological cardiomyocyte hypertrophy via paracrine signalling between endothelial cells and cardiomyocytes. We investigated whether a decrease in circulating soluble VEGFR-2 (sVEGFR-2) levels is associated with poor prognosis in patients with chronic heart failure (HF)., Methods and Results: We performed a multicentre prospective cohort study of 1024 consecutive patients with HF, who were admitted to hospitals due to acute decompensated HF and were stabilized after initial management. Serum levels of sVEGFR-2 were measured at discharge. Patients were followed up over 2 years. The outcomes were cardiovascular death, all-cause death, major adverse cardiovascular events (MACE) defined as a composite of cardiovascular death and HF hospitalization, and HF hospitalization. The mean age of the patients was 75.5 (standard deviation, 12.6) years, and 57% were male. Patients with lower sVEGFR-2 levels were older and more likely to be female, and had greater proportions of atrial fibrillation and anaemia, and lower proportions of diabetes, dyslipidaemia, and HF with reduced ejection fraction (<40%). During the follow-up, 113 cardiovascular deaths, 211 all-cause deaths, 350 MACE, and 309 HF hospitalizations occurred. After adjustment for potential clinical confounders and established biomarkers [N-terminal B-type natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin I, and high-sensitivity C-reactive protein], a low sVEGFR-2 level below the 25th percentile was significantly associated with cardiovascular death [hazard ratio (HR), 1.79; 95% confidence interval (CI), 1.16-2.74] and all-cause death (HR, 1.43; 95% CI, 1.04-1.94), but not with MACE (HR, 1.11; 95% CI, 0.86-1.43) or HF hospitalization (HR, 1.03; 95% CI, 0.78-1.35). The stratified analyses revealed that a low sVEGFR-2 level below the 25th percentile was significantly associated with cardiovascular death (HR, 1.76; 95% CI, 1.07-2.85) and all-cause death (HR, 1.49; 95% CI, 1.03-2.15) in the high-NT-proBNP group (above the median), but not in the low-NT-proBNP group. Notably, the patients with high-NT-proBNP and low-sVEGFR-2 (below the 25th percentile) had a 2.96-fold higher risk (95% CI, 1.56-5.85) for cardiovascular death and a 2.40-fold higher risk (95% CI, 1.52-3.83) for all-cause death compared with those with low-NT-proBNP and high-sVEGFR-2., Conclusions: A low sVEGFR-2 value was independently associated with cardiovascular death and all-cause death in patients with chronic HF. These associations were pronounced in those with high NT-proBNP levels., (© 2021 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

An 82 year-old female patient not suffering from diabetes was transported to our hospital with hyperglycemia (HbA1c 8.2%, blood glucose 584 mg/dL) and mildly increased levels of pancreatic exocrine enzymes (amylase 543 IU/L, lipase 59 U/L, elastase-1 479 ng/dL), while there were no findings indicating pancreatitis. Under a diagnosis of new-onset diabetes, she was discharged with oral hypoglycemic agents, as retention of insulin secretion function [blood glucose 117 mg/dL, serum connecting peptide immunoreactivity (CPR) 1.63 ng/mL] with normalization of the enzymes was confirmed following administration. However, at 73 days after the hospitalization, she returned with diabetic ketoacidosis (blood glucose 910 mg/dL, pH in blood gas analysis 7.15, total blood ketone bodies > 7000 µmol/L) with a transient repeated increase of the enzymes (amylase 382 IU/L, lipase 82 U/L, elastase-1 569 ng/dL) and without pancreatitis. Notably, depletion of insulin secretion (6.1 µg/day in urine, 0.36 ng/mL in serum CPR with no response in glucagon-loading test) was revealed, and serum CPR level remained low after discharge. Together with negative findings for islet-related autoantibodies, the patient was diagnosed with acute-onset type 1B diabetes (T1BD). In the present patient with acute-onset T1BD, a mild increase in pancreatic exocrine enzymes was repeatedly observed, which may mimic fulminant type and raise questions for us about the commonly accepted pathophysiology of T1D. These findings may help to clarify issues related to newly developed T1D in elderly individuals., Competing Interests: Conflict of interestThe authors declare that they have no competing interests., (© The Japan Diabetes Society 2021, corrected publication 2021.)

Background Whether circulating growth differentiation factor 15 (GDF-15) levels differ according to smoking status and whether smoking modifies the relationship between GDF-15 and mortality in patients with coronary artery disease are unclear. Methods and Results Using data from a multicenter, prospective cohort of 2418 patients with suspected or known coronary artery disease, we assessed the association between smoking status and GDF-15 and the impact of smoking status on the association between GDF-15 and all-cause death. GDF-15 was measured in 955 never smokers, 1035 former smokers, and 428 current smokers enrolled in the ANOX Study (Development of Novel Biomarkers Related to Angiogenesis or Oxidative Stress to Predict Cardiovascular Events). Patients were followed up during 3 years. The age of the patients ranged from 19 to 94 years; 67.2% were men. Never smokers exhibited significantly lower levels of GDF-15 compared with former smokers and current smokers. Stepwise multiple linear regression analysis revealed that the log-transformed GDF-15 level was independently associated with both current smoking and former smoking. In the entire patient cohort, the GDF-15 level was significantly associated with all-cause death after adjusting for potential clinical confounders. This association was still significant in never smokers, former smokers, and current smokers. However, GDF-15 provided incremental prognostic information to the model with potential clinical confounders and the established cardiovascular biomarkers in never smokers, but not in current smokers or in former smokers. Conclusions Not only current, but also former smoking was independently associated with higher levels of GDF-15. The prognostic value of GDF-15 on mortality was most pronounced in never smokers among patients with suspected or known coronary artery disease.

Background VEGF-D (vascular endothelial growth factor D) and VEGF-C are secreted glycoproteins that can induce lymphangiogenesis and angiogenesis. They exhibit structural homology but have differential receptor binding and regulatory mechanisms. We recently demonstrated that the serum VEGF-C level is inversely and independently associated with all-cause mortality in patients with suspected or known coronary artery disease. We investigated whether VEGF-D had distinct relationships with mortality and cardiovascular events in those patients. Methods and Results We performed a multicenter, prospective cohort study of 2418 patients with suspected or known coronary artery disease undergoing elective coronary angiography. The serum level of VEGF-D was measured. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death and major adverse cardiovascular events defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke. During the 3-year follow-up, 254 patients died from any cause, 88 died from cardiovascular disease, and 165 developed major adverse cardiovascular events. After adjustment for possible clinical confounders, cardiovascular biomarkers (N-terminal pro-B-type natriuretic peptide, cardiac troponin-I, and high-sensitivity C-reactive protein), and VEGF-C, the VEGF-D level was significantly associated with all-cause death and cardiovascular death but not with major adverse cardiovascular events.. Moreover, the addition of VEGF-D, either alone or in combination with VEGF-C, to the model with possible clinical confounders and cardiovascular biomarkers significantly improved the prediction of all-cause death but not that of cardiovascular death or major adverse cardiovascular events. Consistent results were observed within patients over 75 years old. Conclusions In patients with suspected or known coronary artery disease undergoing elective coronary angiography, an elevated VEGF-D value seems to independently predict all-cause mortality.

Introduction: To detect patients at high risk of developing myocardial infarction, plaque characteristics as well as the degree of stenosis in coronary arteries should be evaluated. However, unstable plaque or severe calcification detected via coronary artery CT (CACT) is not reflected in risk stratification according to current guidelines. It is hypothesised that patients with high-risk findings on CACT (even those without proven history of coronary artery diseases; CAD) should be strictly managed to lower their low-density lipoprotein cholesterol (LDL-C) levels to targets of secondary prevention. Currently, however, there is no evidence based on prospective randomised intervention studies to prove this hypothesis., Methods and Analysis: Patients with mild-to-moderate stenotic lesions with positive remodelling or severe calcification, but without any history of CAD, will be randomly allocated to group A (reduce LDL-C to <120~160 mg/dL according to the primary prevention criteria based on the Japan Atherosclerosis Society (JAS) Guideline for Prevention of Atherosclerotic Cardiovascular Diseases 2017) and group B (reduce LDL-C to <70 mg/dL according to the secondary prevention criteria for high risk based on the JAS Guideline). They will be strictly managed to achieve the LDL-C targets. We will follow-up and evaluate the composite endpoints consisting of major cardiovascular events (death from CAD, non-fatal myocardial infarction, operation for coronary revascularisation and stroke) and stenosis progression or new stenosis development for 3 years., Ethics and Dissemination: The study was approved by the National Hospital Organization Central Research Ethics Committee. The results of this study are scheduled to be published within 2 years after study completion via conference presentation or journal publication., Trial Registration Number: UMIN000031136., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background The lymphatic system has been suggested to play an important role in cholesterol metabolism and cardiovascular disease. However, the relationships of vascular endothelial growth factor-C ( VEGF -C), a central player in lymphangiogenesis, with mortality and cardiovascular events in patients with suspected or known coronary artery disease are unknown. Methods and Results We performed a multicenter, prospective cohort study of 2418 patients with suspected or known coronary artery disease undergoing elective coronary angiography. The primary predictor was serum levels of VEGF -C. The primary outcome was all-cause death. The secondary outcomes were cardiovascular death, and major adverse cardiovascular events defined as a composite of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. During the 3-year follow-up, 254 patients died from any cause, 88 died from cardiovascular disease, and 165 developed major adverse cardiovascular events. After adjustment for established risk factors, VEGF -C levels were significantly and inversely associated with all-cause death (hazard ratio for 1- SD increase, 0.69; 95% confidence interval, 0.60-0.80) and cardiovascular death (hazard ratio, 0.67; 95% confidence interval, 0.53-0.87), but not with major adverse cardiovascular events (hazard ratio, 0.85; 95% confidence interval, 0.72-1.01). Even after incorporation of N-terminal pro-brain natriuretic peptide, contemporary sensitive cardiac troponin-I, and high-sensitivity C-reactive protein into a model with established risk factors, the addition of VEGF -C levels further improved the prediction of all-cause death, but not that of cardiovascular death or major adverse cardiovascular events. Consistent results were observed within 1717 patients with suspected coronary artery disease. Conclusions In patients with suspected or known coronary artery disease, a low VEGF -C value may independently predict all-cause mortality.

Purpose: Currently, the foreign surfaces of various extracorporeal circulation devices are coated with a biocompatible polymer coating agent (BPA), which creates a hydrophilic blood-contacting layer to reduce thrombogenicity, while the membranes in hemodialyzers are not. We aimed to clarify other side effects of BPA-coated membranes by examining the diffusion performance in in vitro experiments., Methods: We used a polyethersulfone membrane (sieving coefficient of albumin is ≤0.01) coated with BPA product, SEC-1TM (Toyobo), in a hemodialyzer. To estimate the diffusion rates of a wide range of molecules, 2 L of saline containing vancomycin, lysozyme, and albumin were recirculated in the circuit configured with a hemodialyzer, and dialyzed continuously using water. The concentrations of sodium, vancomycin, lysozyme, and albumin were measured every 5 minutes for 30 minutes and compared in experiments with BPA-coated (n = 4) and BPA-noncoated (n = 4) membranes., Results: The removal rates of sodium and vancomycin after 5 minutes of dialysis (n = 24) were significantly higher in BPA-coated than noncoated membranes, while those of lysozyme and albumin were not significantly different. The removal rates of sodium and vancomycin after 30 minutes of dialysis (n = 4) were significantly higher, and those of lysozyme were significantly lower in BPA-coated than noncoated membranes, while those of albumin were not significantly different., Conclusions: The preliminary study suggests that BPA-coated membranes enhanced the diffusion rate of molecules with low and middle molecular weight without affecting the sieving coefficient of albumin. Thus, BPA coating can enhance the dialysis performance of membranes.

The heart is an organ where primary malignant tumors rarely develop. In particular, the incidence of cardiac rhabdomyosarcoma (RMS) is extremely low. It has been reported that the risk of second malignant tumors in mediastinum is increased by radiotherapy in women with breast cancer. However, little is known about the association between irradiation to heart and cardiac RMS. Here, we report a case of a 68-year-old woman with primary cardiac RMS. She suddenly presented syncope at a workplace, and was taken to the emergency room at our hospital. Several imaging tests, including echocardiogram and cine magnetic resonance imaging, detected two tumors in the right ventricle (RV) and its outflow tract, which had almost obstructed the main trunk of the pulmonary artery (PA). To avoid sudden PA occlusion by the tumor, we emergently performed surgical excision of the tumors from the RV. Pathological analysis revealed that these tumors were embryonal type RMS. She had received radiotherapy after mastectomy for left breast cancer 18 years previously, and no recurrence of breast cancer had been detected. This cardiac RMS is considered as a second malignant tumor related to radiotherapy for breast cancer. < Learning objective: We experienced a 68-year-old woman having two tumors of the RMS in RV, who had received radiotherapy for left breast cancer 18 years previously and had previously presented no recurrence. There is literature suggesting that radiotherapy may increase the risk of soft-tissue sarcoma in women with breast cancer. We should be aware of cardiac RMS as a second malignant tumor related to radiotherapy for breast cancer, although its incidence is extremely low.>.

Background: Hepatic steatosis is considered one of the features of metabolic syndrome (MetS). Polyunsaturated fatty acid (PUFA) metabolism is modulated in obesity. However, it has yet to be fully elucidated whether a serum PUFA profile is associated with hepatic steatosis., Objective: We aimed to clarify the relationship between a serum PUFA profile and liver lipid content., Methods: A cross-sectional study was conducted on 288 patients with dyslipidemia, diabetes, or coronary artery disease on statin therapy. Several PUFAs were measured, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), dihomo-γ-linolenic acid (DGLA) and arachidonic acid (AA) in serum lipids, and Δ-5 desaturase (D5D) activity was estimated by AA to DGLA ratio. Abdominal computed tomography (CT) measured visceral fat area (VFA) and the ratio of CT attenuation for liver to spleen (L/S)., Results: The L/S ratio showed significant correlations with serum DGLA level and D5D activity (p<0.0001 for both). Serum DGLA level and D5D activity were significantly correlated with body mass index (BMI) or VFA, and with Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) (p<0.0001 for all). Multivariate logistic analysis revealed that a high DGLA level or low D5D activity was a significant determinant for hepatic steatosis (p<0.0001 for both) independent of BMI and HOMA-IR. ROC analysis revealed that they significantly enhanced the value of MetS-related factors in predicting hepatic steatosis (p<0.05 for both)., Conclusions: A high DGLA level and low D5D activity in serum lipids may be useful markers predicting hepatic steatosis incrementally to MetS-related conventional factors., (Copyright © 2016 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.)

Purpose: Extracorporeal circulation circuits used in cardiopulmonary bypass surgeries are increasingly being coated with polymer materials to reduce the thrombogenicity of extracorporeal devices. However, a haemoconcentrator, which corrects haematocrit and electrolyte imbalances, is not coated with polymers. In this study, we sought to assess the filtration performance of polymer-coated haemoconcentrators in order to obtain insight into their prospects for use in clinical applications., Methods: In vitro experiments were performed to evaluate the water pressure and flow properties of polymer-coated haemoconcentrators by comparing 3 polymer-coated haemoconcentrators with 3 non-coated haemoconcentrators. The cross-sectional surfaces of both types of haemoconcentrators were observed using a scanning electron microscope (SEM)., Results: The slopes of the regression lines for estimating the filtrated fluid flow as a function of the transmembrane pressure were 6.286 ± 0.320 for polymer-coated haemoconcentrators and 3.712 ± 0.170 for non-coated haemoconcentrators. These slopes were found to be significantly different and indicate that the filtration velocity is enhanced in polymer-coated haemoconcentrators over that in non-coated haemoconcentrators. However, the hollow fibre damage observed by SEM was not shown to contribute to higher filtration flow in the polymer-coated haemoconcentrator. Taking these results into consideration, we hypothesise that a polymer coating makes a foreign surface on a hollow fibre slippery, owing to the hydrophobicity of the polymer, thereby enhancing the velocity of the filtration., Conclusions: The results of this preliminary investigation suggest that a polymer coating can enhance the filtration performance of a haemoconcentrator and that polymer-coated haemoconcentrators might be useful in clinical applications.

Objectives: To investigate the sterility and biocompatibility of a stored open-reservoir cardiopulmonary bypass circuit maintained on standby., Methods: A total of four cardiopulmonary bypass circuits were assembled, primed and left to recirculate. One unit was placed in a positive-pressure operating room and the other three were placed in the intensive care unit. The primed solutions, which employed Ringer's acetate, hydroxyethylated starch and hydrate steroid, were sampled after 0, 24, 48, 72, 96, 120 and 144 h in all cardiopulmonary bypass circuits to measure the bacteria count, endotoxin count and chemical substances within the primed solution. Chemical substances were detected by assessing the following: the total organic carbon by the combustion oxidation infrared spectrometry, and molecular weight spread by gel permeation chromatography. The environments were left unattended and were uncovered during the storage period to mimic the clinical scenario., Results: There were no bacteria in any of the primed solutions, and only very minute concentrations of endotoxins were detected, both in the operating room and in the intensive care unit. The total organic carbon concentration was slightly more concentrated in the 144-h samples when compared with that in the 0-h samples. However, the molecular weight spread of the 0-h sample was identical to that in the 144-h sample., Discussion: With regard to the presence of bacteria and endotoxins, we noted that the hardshell reservoirs in the cardiopulmonary bypass circuit were effectively sealed and not invaded by bacteria. With regard to the presence of chemical substances, we noted that an increase in total organic carbon concentration was caused by bedewing, and that there was no release of chemical substances such as a polymer-coating agent, or other molecular materials in the primed solution., Conclusions: There was no contamination or release of chemical substances in 6-day old cardiopulmonary bypass circuits maintained on standby, confirming that they are safe to use in terms of sterility and biocompatibility., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

The recent increase in populations with obesity is a worldwide social problem, and the enhanced susceptibility of obese people to metabolic and cardiovascular diseases has become a growing health threat. An understanding of the molecular basis for obesity-associated disease development is required to prevent these diseases. Many studies have revealed that the mechanism involves various bioactive molecules that are released from adipose tissues and designated as adipocytokines/adipokines. Adiponectin is an adipocytokine that exerts insulin-sensitizing effects in the liver and skeletal muscle via adenosine monophosphate-activated protein kinase and proliferator-activated receptor α activation. Additionally, adiponectin can suppress atherosclerosis development in vascular walls via various anti-inflammatory effects. In contrast, oxidative stress is a harmful factor that systemically increases during obesity and promotes the development of diabetes, atherosclerosis, and various other diseases. In obese mice, oxidative stress is enhanced in adipose tissue before diabetes development, but not in the liver, skeletal muscle, and aorta, suggesting that in obesity, adipose tissue may be a major source of reactive oxygen species (ROS). ROS suppress adiponectin production in adipocytes. Treatment of obese mice with anti-oxidative agents improves insulin resistance and restores adiponectin production. Recent studies have demonstrated that adiponectin protects against oxidative stress-induced damage in the vascular endothelium and myocardium. Thus, decreased circulating adiponectin levels and increased oxidative stress, which are closely linked to each other, should be deeply involved in obesity-associated metabolic and cardiovascular disease pathogenesis.

Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome, typically affecting young, healthy women, particularly during the peripartum period. Oral contraceptive use is also recognized as a risk factor for SCAD. In the present report, we describe a case of a young woman with an anterior wall myocardial infarction caused by SCAD of the left anterior descending artery (LAD). The event was probably associated with the patient's oral contraceptive use. The patient underwent percutaneous coronary intervention, and she did not experience any recurrent chest pain or other cardiac symptoms. Although the coronary angiography revealed good LAD flow and no symptoms after 6 months, cardiac computed tomography and intravascular ultrasound revealed that LAD dissection was still present. We continued to closely follow-up the patient without initiating any additional intervention, and the patient has had no cardiac event for up to 4 years of follow-up. < Learning objective: We aimed to present a case of spontaneous coronary artery dissection, with a long-term residual dissection. Coronary computed tomography aided the diagnosis of the residual dissection, which was not detected by coronary angiography.>.

Obesity, especially of the abdominal type, is a health problem that constitutes metabolic syndrome and increases the incidence of various diseases, including diabetes, hypertension, dyslipidemia, atherosclerosis, and cancer. Various mechanisms linking obesity to these associated diseases have been postulated. One candidate is oxidative stress, which has been implicated in vascular complications of diabetes and in pancreatic -cell failure in diabetes. Notably, obese people without diabetes also display elevated levels of systemic oxidative stress. In addition, levels of oxidative stress are increased in the adipose tissue in obese mice. Treating obese mice with antioxidant agents attenuates the development of diabetes. In 3T3-L1 adipocytes, increases in reactive oxygen species (ROS) occur with lipid accumulation; the addition of free fatty acids elevates ROS generation further. Thus, adipose tissue represents an important source of ROS; ROS may contribute to the development of obesity-associated insulin resistance and type 2 diabetes. Moreover, the levels of oxidative stress present in several other types of cells or tis-sues, including those in the brain, arterial walls, and tumors, have been implicated in the pathogenesis associated with hypertension, atherosclerosis, and cancer. The increased levels of systemic oxidative stress that occur in obesity may contribute to the obesity-associated development of these diseases., (© 2013 Asian Oceanian Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.)

Background: Liaison critical paths (LCPs) for coronary artery disease (CAD) were developed to support collaborative care for CAD patients between cardiologists in emergency hospitals and referring physicians through sharing of medical information, including cardioprotective medications and cardiovascular risk factors. However, little is known about the effects of LCPs in practice., Methods: We conducted an observational study of CAD patients undergoing percutaneous coronary intervention in our hospital between September 2007 and June 2010; these patients were managed with an LCP by referring physicians after discharge. We surveyed implementation of scheduled hospital visits, prescription of cardioprotective medicines, and risk factor measurements 6 and 12 months after discharge., Results: Implementation rate of hospital visits was significantly elevated from 50.7% to 89.3% after establishing LCPs. At the 12-month visit, prescription rates for anti-platelet drugs, statins, β-blockers, and angiotensin-converting enzyme inhibitors or angiotensin II type I receptor blockers were 99.7%, 95.0%, 77.1%, and 74.3%, respectively. Target achievement rates for low-density lipoprotein cholesterol (LDL-C; < 100 mg/dL) and high-density lipoprotein cholesterol (HDL-C; ≥ 40 mg/dL) significantly increased from 48.6% to 64.5% and 62.0% to 82.7%, respectively, while those for body mass index (BMI; < 25 kg/m(2)), blood pressure (< 130/80 mmHg), triglycerides (< 150 mg/dL), and HbA1c (< 7.0 %) were unchanged. BMI, triglycerides, HDL-C, LDL-C, and HbA1c levels significantly improved in patients who implemented all visits. Moreover, risk factor management did not differ significantly between cardiologists and non-cardiologists using LCPs., Conclusions: LCPs for CAD may facilitate implementation of optimal medical therapy and target achievement of risk factors in practice., Keywords: Liaison critical path; Coronary artery disease; Cardiovascular prevention; Risk factors; Clinical practice.

Oxidative stress plays an important role in obesity-related metabolic diseases. Glutathione peroxidase (GPX) is an antioxidant enzyme downregulated in adipose tissue of obese mice. However, the role of GPX in adipocytes remains elusive. The objective of this study was to clarify the pathophysiological changes in GPX activity and glutathione metabolism and their roles in the pathogenesis of insulin resistance in adipocytes. To achieve this goal, we measured cellular GPX activity, glutathione (GSH) contents, GSH/GSSG ratio, and mRNA expression of gamma-glutamylcysteine synthetase (gamma-GCS), a rate-limiting enzyme for de novo GSH synthesis, in adipose tissue of control and ob/ob mice and in 3T3-L1 adipocytes treated with insulin, H(2)O(2), free fatty acid (FFA), or TNFalpha. Furthermore, we investigated the effects of GPX inhibition with a specific GPX inhibitor or RNA interference against GPX, H(2)O(2), and reduced GSH on insulin signaling in 3T3-L1 adipocytes. ob/ob Mice showed not only a decrease in cellular activity of GPXs (GPX1, -4, and -7) but also an increase in gamma-GCS expression, resulting in increased GSH contents in adipose tissue. These alterations in glutathione metabolism were also observed during differentiation of 3T3-L1 cells and their exposure to insulin, FFA, or H(2)O(2). Inhibition of GPX activity, addition of GSH, and H(2)O(2) resulted in impaired insulin signaling in 3T3-L1 adipocytes. These results suggest that decreased GPX activity and increased gamma-GCS expression lead to overaccumulation of GSH, which might be involved in the pathogenesis of insulin resistance in obesity.

Adiponectin is exclusively expressed in adipose tissue and secreted from adipocytes, and shows anti-diabetic and anti-atherogenic properties. However, the precise transcriptional mechanism of adiponectin remains elusive. In this study, the 5' flanking promoter region of human adiponectin gene was analyzed using UCSC genome browser, and a 10 390-bp fragment, containing an evolutionally conserved region among species, was investigated. The luciferase reporter assay using this fragment identified a novel distal enhancer of human adiponectin gene. Promoter constructs with the distal enhancer exhibited high promoter activities in 3T3-L1 mature adipocytes. However, no such activity was observed in other types of cell lines. The distal enhancer is highly conserved, and contains two completely conserved CCAAT boxes. In 3T3-L1 mature adipocytes, deletion or each point mutation of these CCAAT boxes markedly reduced luciferase activity driven by adiponectin promoter. Knockdown of CCAAT/enhancer-binding protein alpha (CEBPA; also known as C/EBPalpha) using small interfering RNA diminished adiponectin mRNA expression and luciferase activity driven by adiponectin promoter with the distal enhancer. However, adiponectin promoter with each mutation of two CCAAT boxes in the distal enhancer did not respond to knockdown of CEBPA expression. Furthermore, CEBPA bound to the distal enhancer both in vitro and in vivo. We also identified a proximal promoter region responsible for transcriptional activation by the distal enhancer in human adiponectin gene. Our results indicate that CEBPA plays a pivotal role in the transcription of human adiponectin gene via the distal enhancer and proximal region in its promoter.

In adipose tissue of obese mice, the expression of catalase, an anti-oxidant enzyme, significantly decreases, which may cause insufficient elimination of hydrogen peroxide, but it does not in liver or skeletal muscle. However, the precise regulatory mechanism of catalase expression in adipocytes has not been fully defined. Here, we demonstrated that adipose tissues highly expressed catalase on the level comparable to liver and kidney, and treatment of mice with PPARgamma agonist significantly enhanced catalase expression in adipose tissue but not in liver. In 3T3-L1 cells, mRNA expression of catalase was up-regulated by the induction for adipose differentiation, and down-regulated by TNFalpha, in parallel with alterations in PPARgamma expression. PPARgamma agonist significantly enhanced catalase mRNA and activity. Furthermore, we newly identified a remote enhancer region containing two functional PPARgamma binding sites in mouse catalase gene. Collectively, our findings suggest that PPARgamma plays a crucial role in the expression of catalase in adipocytes.

In the West of Scotland Coronary Prevention Study (WOSCOPS), treatment of hypercholesterolemic men with pravastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, reduced their likelihood to progress to diabetes mellitus by 30%. However, the mechanism of this effect of pravastatin has not been investigated. In the current study, we examined the effect of pravastatin on the development of diabetes in obese diabetic mice, and on the insulin-induced glucose uptake and adiponectin production. Pravastatin treatment attenuated the development of diabetes in db/db and high fat/high sucrose diet-fed C57BL/6J mice. An in vivo glucose transport assay showed that pravastatin upregulated glucose uptake in adipose tissue. Insulin-stimulated glucose uptake was enhanced in primary adipocytes isolated from pravastatin-treated mice. Pravastatin treatment increased adiponectin production in 3T3-L1 adipocytes. Plasma adiponectin levels were significantly increased in pravastatin-treated mice. Analyses of plasma samples from the WOSCOPS biobank indicated a significant increase of plasma adiponectin levels with pravastatin treatment (placebo -0.28+/-0.34 microg/ml versus pravastatin +1.47+/-0.33 microg/ml, p=0.0003). Taken together, our findings suggest that pravastatin may have beneficial effects on adipose tissue, which may partly explain the reduction of the development of diabetes by pravastatin treatment.

Background & Aims: Adiponectin, an adipose tissue-derived hormone, exhibits anti-inflammatory properties and has various biological functions, such as increasing insulin sensitivity, reducing hypertension, and suppressing atherosclerosis, liver fibrosis, and tumor growth. The aim of the present study was to determine the effect of adiponectin on intestinal inflammation., Methods: We investigated the effect of adiponectin on dextran sulfate sodium (DSS)-induced colitis by using adiponectin-knockout (APN-KO) mice and an adenovirus-mediated adiponectin expression system. We also examined the contribution of adiponectin deficiency to trinitrobenzene sulfonic acid (TNBS)-induced colitis. In vitro, we examined the effect of adiponectin on intestinal epithelial cells., Results: After administration of 0.5% DSS for 15 days, APN-KO mice developed much more severe colitis compared with wild-type mice. The messenger RNA expression levels of chemokines were significantly higher in the colonic tissues of DSS-treated APN-KO mice compared with wild-type mice, accompanied by increased cellular infiltration, including macrophages. Adenovirus-mediated supplementation of adiponectin significantly attenuated the severity of colitis, but there were no differences in the severity of TNBS-induced colitis between the 2 groups. Adiponectin receptors were expressed in intestinal epithelial cells, and adiponectin inhibited lipopolysaccharide-induced interleukin-8 production in intestinal epithelial cells., Conclusions: Adiponectin is protective against DSS-induced murine colitis, probably due to the inhibition of chemokine production in intestinal epithelial cells and the following inflammatory responses, including infiltration of macrophages and release of proinflammatory cytokines.

Fat tissue produces a variety of secreted proteins (adipocytokines) with important roles in metabolism. We isolated a newly identified adipocytokine, visfatin, that is highly enriched in the visceral fat of both humans and mice and whose expression level in plasma increases during the development of obesity. Visfatin corresponds to a protein identified previously as pre-B cell colony-enhancing factor (PBEF), a 52-kilodalton cytokine expressed in lymphocytes. Visfatin exerted insulin-mimetic effects in cultured cells and lowered plasma glucose levels in mice. Mice heterozygous for a targeted mutation in the visfatin gene had modestly higher levels of plasma glucose relative to wild-type littermates. Surprisingly, visfatin binds to and activates the insulin receptor. Further study of visfatin's physiological role may lead to new insights into glucose homeostasis and/or new therapies for metabolic disorders such as diabetes.

Pten is an important phosphatase, suppressing the phosphatidylinositol-3 kinase/Akt pathway. Here, we generated adipose-specific Pten-deficient (AdipoPten-KO) mice, using newly generated Acdc promoter-driven Cre transgenic mice. AdipoPten-KO mice showed lower body and adipose tissue weights despite hyperphagia and enhanced insulin sensitivity with induced phosphorylation of Akt in adipose tissue. AdipoPten-KO mice also showed marked hyperthermia and increased energy expenditure with induced mitochondriagenesis in adipose tissue, associated with marked reduction of p53, inactivation of Rb, phosphorylation of cyclic AMP response element binding protein (CREB) and increased expression of Ppargc1a, the gene that encodes peroxisome proliferative activated receptor gamma coactivator 1 alpha. Physiologically, adipose Pten mRNA decreased with exposure to cold and increased with obesity, which were linked to the mRNA alterations of mitochondriagenesis. Our results suggest that altered expression of adipose Pten could regulate insulin sensitivity and energy expenditure. Suppression of adipose Pten may become a beneficial strategy to treat type 2 diabetes and obesity.

We reported previously that angiopoietin-like protein3 (ANGPTL3), a liver-specific secretory factor, increased plasma triglyceride (TG) via inhibition of lipoprotein lipase and free fatty acid (FFA) by activating adipose-lipolysis. The current study examined the regulation of Angptl3 by leptin and insulin, both of which are key players in the metabolic syndrome. Angptl3 expression and plasma ANGPTL3 levels were increased in leptin-resistant C57BL/6J(db/db) and -deficient C57BL/6J(ob/ob) mice, relative to the control. Leptin supplements decreased Angptl3 gene expression and plasma ANGPTL3 in C57BL/6J(ob/ob) mice. The changes of Angptl3 were associated with alterations of plasma TG and FFA levels. Leptin treatment directly suppressed Angptl3 gene expression in hepatocytes. Angptl3 gene expression and plasma protein levels were also increased in insulin-deficient streptozotocin-treated mice. Insulin treatment of hepatocytes decreased Angptl3 gene expression and protein secretion. Our results suggest that elevated ANGPTL3 by leptin- or insulin-resistance is attributed to increased plasma TG and FFA concentrations in obesity.

Recent progress in adipocyte-biology shows that adipocytes are not merely fat-storing cells but that they secrete a variety of hormones, cytekines, growth factors and other bioactive substabces, conceptualized as adipocytokines. These include plasminogen activator inhibitor 1(PAI-1), tumor necrosis factor(TNF-alpha), leptin and adiponectin. Dysregulated productions of these adipocytekines participate in the pathogenesis of obesity-associated metabolic syndrome such as insulin resistance, type 2 diabetes, hyperlipidemia, and vascular diseases. Increased productions of PAI-1 and TNF-alpha from accumulated fat contribute to the formation of thrombosis and insulin resistance in obesity, respectively. Lack of leptin causes metabolic syndrome. Adiponectin exerts insulin-sensitizing and anti-atherogenic effects, hence decrease of plasma adiponectin is causative for insulin resistance and atherosclerosis in obesity.

Skeletal muscle is involved in the homeostasis of glucose and lipid metabolism. We hypothesized that the skeletal muscle produces and secretes bioactive factor(s), similar to adipocytokines secreted by fat tissue. Here, we report the identification of a novel secretory factor, musclin, by signal sequence trap of mouse skeletal muscle cDNAs. Musclin cDNA encoded 130 amino acids, including NH(2)-terminal 30-amino acid signal sequence. Musclin protein contained a region homologous to natriuretic peptide family, and KKKR, a putative serine protease cleavage site, similar to the natriuretic peptide family. Full-length musclin protein and KKKR-dependent cleaved form were secreted in media of musclin cDNA-transfected mammalian cell cultures. Musclin mRNA was expressed almost exclusively in the skeletal muscle of mice. Musclin mRNA levels in skeletal muscle were markedly low in fasted, increased upon re-feeding, and were low in streptozotocin-treated insulin-deficient mice. Musclin mRNA expression was induced at late stage in the differentiation of C2C12 myocytes. In myocytes, insulin increased, while epinephrine, isoproterenol, and forskolin reduced musclin mRNA, all of which are known to increase the cellular content of cyclic AMP, a counter-regulator to insulin. Pathologically, overexpression of musclin mRNA was noted in the muscles of obese insulin-resistant KKAy mice. Functionally, recombinant musclin significantly attenuated insulin-stimulated glucose uptake and glycogen synthesis in myocytes. In conclusion, we identified musclin, a novel skeletal muscle-derived secretory factor. Musclin expression level is tightly regulated by nutritional changes and its physiological role could be linked to glucose metabolism.

The nuclear receptors liver X receptor (LXR) alpha and LXRbeta serve as oxysterol receptors and regulate the expression of genes involved in lipid metabolism. LXR activation induces the expression of ATP-binding cassette (ABC) transporters, such as ABCG5 and ABCG8, which inhibit intestinal absorption of cholesterol and phytosterols. Although several synthetic LXR agonists have been generated, these compounds have limited clinical application, because they cause hypertriglycemia by inducing the expression of lipogenic genes in the liver. We synthesized derivatives of phytosterols and found some of them to act as LXR agonists. Among them, YT-32 [(22E)-ergost-22-ene-1alpha,3beta-diol], which is related to ergosterol and brassicasterol, is the most potent LXR agonist. YT-32 directly bound to LXRalpha and LXRbeta and induced the interaction of LXRalpha with cofactors, such as steroid receptor coactivator-1, as effectively as the natural ligands, 22(R)-hydroxycholesterol and 24(S),25-epoxycholesterol. Although the nonsteroidal synthetic LXR agonist T0901317 induced the expression of intestinal ABC transporters and liver lipogenic genes, oral administration of YT-32 selectively activated intestinal ABC transporters in mice. Unlike T0901317 treatment, YT-32 inhibited intestinal cholesterol absorption without increasing plasma triglyceride levels. The phytosterol-derived LXR agonist YT-32 might selectively modulate intestinal cholesterol metabolism.

Adiponectin is a fat-derived hormone with antidiabetic and antiatherogenic properties. Hypoadiponectinemia seen in obesity is associated with insulin-resistant diabetes and atherosclerosis. Thiazolidinediones, peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists, have been shown to increase plasma adiponectin levels by the transcriptional induction in adipose tissues. However, the precise mechanism of such action is unknown. In this study, we have identified a functional PPAR-responsive element (PPRE) in human adiponectin promoter. PPAR-gamma/retinoid X receptor (RXR) heterodimer directly bound to the PPRE and increased the promoter activity in cells. In adipocytes, point mutation of the PPRE markedly reduced the basal transcriptional activity and completely blocked thiazolidinedione-induced transactivation of adiponectin promoter. We have also identified a responsive element of another orphan nuclear receptor, liver receptor homolog-1 (LRH-1), in adiponectin promoter. LRH-1 was expressed in 3T3-L1 cells and rat adipocytes. LRH-1 bound specifically to the identified responsive element (LRH-RE). LRH-1 augmented PPAR-gamma-induced transactivation of adiponectin promoter, and point mutation of the LRH-RE significantly decreased the basal and thiazolidinedione-induced activities of adiponectin promoter. Our results indicate that PPAR-gamma and LRH-1 play significant roles in the transcriptional activation of adiponectin gene via the PPRE and the LRH-RE in its promoter.

The KK/San obese and diabetic mouse, a mutant strain from KK obese mice, exhibits significantly low plasma triglyceride levels. In KK/San mice, genetic analysis identified a mutation in the gene encoding angiopoietinlike protein 3 (Angptl3), a liver-specific secretory protein, which had suppressive effect on lipoprotein lipase activity. In the current study, LXR ligands augmented Angptl3 mRNA expression and protein production in hepatoma cells. LXR ligands and LXR.retinoid X receptor (RXR) complex increased the promoter activity of Angptl3 gene. Serial deletion and point mutation of Angptl3 promoter identified an LXR response element (LXRE). Gel mobility shift assay showed the direct binding of LXR.RXR complex to the LXRE of the Angptl3 promoter. Furthermore, treatment of mice with synthetic LXR ligand caused triglyceride accumulation in the liver and plasma, which was accompanied by induction of hepatic mRNAs of several LXR target genes, including sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and Angptl3. In Angptl3-deficient C57BL/6J mice, LXR ligand did not cause hypertriglyceridemia but accumulation of triglyceride in the liver. Our results demonstrate that Angptl3 is a direct target of LXR and that induction of hepatic Angptl3 accounts for hypertriglyceridemia associated with the treatment of LXR ligand.

Our previous work identified a genetic mutation in the gene encoding angiopoietin-like protein 3 (Angptl3) in KK/Snk mice (previously KK/San), a mutant strain of KK obese mice. KK/Snk had significantly lower plasma triglyceride and free fatty acid (FFA) than KK mice. Human ANGPTL3 treatment increased both plasma triglyceride and FFA. ANGPTL3 inhibited the activity of lipoprotein lipase, which accounted for the increase of plasma triglyceride. The mechanism how ANGPTL3 affects plasma FFA has not been known. The current study reveals that ANGPTL3 targets on adipose cells and induces lipolysis. Both plasma FFA and glycerol decreased in KK/Snk and increased by the treatment of human ANGPTL3. Specific bindings of ANGPTL3 to adipose cells were shown using fluorescence-labeled protein visually and 125I-labeled protein by the binding analysis. Furthermore, ANGPTL3 activated the lipolysis to stimulate the release of FFA and glycerol from adipocytes. We conclude that ANGPTL3 is a liver-derived lipolytic factor targeting on adipocyte.

Obesity is more linked to vascular disease, including atherosclerosis and restenotic change, after balloon angioplasty. The precise mechanism linking obesity and vascular disease is still unclear. Previously we have demonstrated that the plasma levels of adiponectin, an adipose-derived hormone, decreases in obese subjects, and that hypoadiponectinemia is associated to ischemic heart disease. In current the study, we investigated the in vivo role of adiponectin on the neointimal thickening after artery injury using adiponectin-deficient mice and adiponectin-producing adenovirus. Adiponectin-deficient mice showed severe neointimal thickening and increased proliferation of vascular smooth muscle cells in mechanically injured arteries. Adenovirus-mediated supplement of adiponectin attenuated neointimal proliferation. In cultured smooth muscle cells, adiponectin attenuated DNA synthesis induced by growth factors including platelet-derived growth factor, heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF), basic fibroblast growth factor, and EGF and cell proliferation and migration induced by HB-EGF. In cultured endothelial cells, adiponectin attenuated HB-EGF expression stimulated by tumor necrosis factor alpha. The current study suggests an adipo-vascular axis, a direct link between fat and artery. A therapeutic strategy to increase plasma adiponectin should be useful in preventing vascular restenosis after angioplasty.