Kuniaki Hirose

Different responses to oxidized low-density lipoproteins in human polarized macrophages

BackgroundOxidized low-density lipoprotein (oxLDL) uptake by macrophages plays an important role in foam cell formation. It has been suggested the presence of heterogeneous subsets of macrophage, such as M1 and M2, in human atherosclerotic lesions. To evaluate which types of macrophages contribute to atherogenesis, we performed cDNA microarray analysis to determine oxLDL-induced transcriptional alterations of each subset of macrophages.ResultsHuman monocyte-derived macrophages were polarized toward the M1 or M2 subset, followed by treatment with oxLDL. Then gene expression levels during oxLDL treatment in each subset of macrophages were evaluated by cDNA microarray analysis and quantitative real-time RT-PCR. In terms of high-ranking upregulated genes and functional ontologies, the alterations during oxLDL treatment in M2 macrophages were similar to those in nonpolarized macrophages (M0). Molecular network analysis showed that most of the molecules in the oxLDL-induced highest scoring molecular network of M1 macrophages were directly or indirectly related to transforming growth factor (TGF)-β1. Hierarchical cluster analysis revealed commonly upregulated genes in all subset of macrophages, some of which contained antioxidant response elements (ARE) in their promoter regions. A cluster of genes that were specifically upregulated in M1 macrophages included those encoding molecules related to nuclear factor of kappa light polypeptide gene enhancer in B-cells (NF-κB) signaling pathway. Quantitative real-time RT-PCR showed that the gene expression of interleukin (IL)-8 after oxLDL treatment in M2 macrophages was markedly lower than those in M0 and M1 cells. HMOX1 gene expression levels were almost the same in all 3 subsets of macrophages even after oxLDL treatment.ConclusionsThe present study demonstrated transcriptional alterations in polarized macrophages during oxLDL treatment. The data suggested that oxLDL uptake may affect TGF-β1- and NF-κB-mediated functions of M1 macrophages, but not those of M0 or M2 macrophages. It is likely that M1 macrophages characteristically respond to oxLDL.

Single Administration of α-Glucosidase Inhibitors on Endothelial Function and Incretin Secretion in Diabetic Patients With Coronary Artery Disease - Juntendo University Trial: Effects of Miglitol on Endothelial Vascular Reactivity in Type 2 Diabetic Patients With Coronary Heart Disease (J-MACH) -

Background: Post-prandial hyperglycemia, hyperlipidemia, and endothelial dysfunction play an important role in the pathogenesis of atherosclerosis. Improvement in post-prandial hyperglycemia on α-glucosidase inhibitors (α-GIs) is associated with a risk reduction of cardiovascular diseases, but the post-prandial effects of α-GIs on endothelial function and incretin secretion in type 2 diabetic patients with coronary artery disease (CAD) remain unclear. Methods and Results: The post-prandial effects of a single administration of miglitol and voglibose on endothelial function and changing levels of glucose, insulin, lipids, glucagon-like peptide (GLP)-1, and gastric inhibitory polypeptide (GIP) were compared after a standard meal loading in 11 diabetic patients with CAD, using a placebo-controlled cross-over design. The changing levels of glucose, insulin and triglycerides at 60 min were significantly lower in the miglitol group than in the voglibose and placebo groups (all P<0.01). GLP-1 levels were significantly higher at 120 min (P<0.05) and GIP levels were significantly lower at 30 min and 60 min (P<0.05) in the miglitol group compared to other treatments. The reactive hyperemia duration at 120 min was significantly maintained in the miglitol group compared to the other groups. Conclusions: A single administration of miglitol significantly improved post-prandial glucose/lipid metabolism, incretin secretion, and endothelial dysfunction in diabetic patients with CAD, suggesting that miglitol may be a useful anti-atherogenic agent (UMIN000002264).  (Circ J 2010; 74: 1471 - 1478)

Effects of calcium channel blockers on glucose tolerance, inflammatory state, and circulating progenitor cells in non-diabetic patients with essential hypertension: a comparative study between azelnidipine and amlodipine on glucose tolerance and endothelial function--a crossover trial (AGENT).

BackgroundHypertension is associated with impaired glucose tolerance and insulin resistance. Medical treatment that interferes with various steps in the renin-angiotensin system improves glucose tolerance and insulin resistance. However, it remains unclear if long-acting calcium channel blockers (CCBs) such as azelnidipine and amlodipine affect glucose tolerance and insulin resistance in clinical practice.MethodsSeventeen non-diabetic patients with essential hypertension who had controlled blood pressure levels using amlodipine (5 mg/day) were enrolled in this study. After randomization, either azelnidipine (16 mg/day) or amlodipine (5 mg/day) was administered in a crossover design for 12-weeks. At baseline and the end of each CCB therapy, samples of blood and urine were collected and 75 g oral glucose tolerance test (OGTT) was performed. In addition, hematopoietic progenitor cells (HPCs) were measured at each point by flow cytometry and endothelial functions were measured by fingertip pulse amplitude tonometry using EndoPAT.ResultsAlthough blood pressure levels were identical after each CCB treatment, the heart rate significantly decreased after azelnidipine administration than that after amlodipine administration (P < 0.005). Compared with amlodipine administration, azelnidipine significantly decreased levels of glucose and insulin 120 min after the 75 g OGTT (both P < 0.05). Serum levels of high-sensitivity C-reactive protein (P = 0.067) and interleukin-6 (P = 0.035) were decreased. Although endothelial functions were not different between the two medication groups, the number of circulating HPCs was significantly increased after azelnidipine administration (P = 0.016).ConclusionsThese results suggest that azelnidipine treatment may have beneficial effects on glucose tolerance, insulin sensitivity, the inflammatory state, and number of circulating progenitor cells in non-diabetic patients with essential hypertension.

Involvement of cholesterol-enriched microdomains in class A scavenger receptor-mediated responses in human macrophages

OBJECTIVE Lipid rafts are cholesterol-enriched microdomains on cell membranes. We hypothesized that these microdomains could involve modified low-density lipoprotein (LDL) uptake. METHODS AND RESULTS Co-localizations of cholesterol-enriched microdomains and CD204 during the uptake of acetyl LDL (AcLDL) and oxidized LDL were observed using Alexa488-labeled polyethylene glycol cholesteryl ester, which is a sensitive probe used to analyze the dynamics of cholesterol-rich lipid microdomains in living cells. The lipid raft disruptors, methyl-β cyclodextrin and filipin, inhibited the uptake of AcLDL. CD204 siRNA treatments significantly reduced AcLDL uptake by 80%. We also demonstrated the presence of CD204 in the detergent-resistant membrane fraction (DRM) by immunoblotting analysis. The ratio of CD204/flotillin-1 in DRM was increased 11.5-fold by modified LDL administration. The PI3 kinase inhibitor LY294002, but not the Src kinase inhibitor PP1 or the Gαi/o inhibitor pertussis toxin, inhibited modified LDL uptake. The production of interleukin (IL)-8, but not CCL2, CXCL2, CXCL3, IL-6 or tumor necrosis factor-α was increased by AcLDL administration. The AcLDL-induced IL-8 production was inhibited by LY294002 and filipin. CONCLUSIONS These data firstly demonstrated that PI3 kinase-associated cholesterol-enriched microdomains are involved in CD204-mediated modified LDL uptake in human macrophages. Cholesterol-enriched microdomains may play a critical role in inflammatory processes.

High levels of very long-chain saturated fatty acid in erythrocytes correlates with atherogenic lipoprotein profiles in subjects with metabolic syndrome

AIM Very long chain saturated fatty acid (VLCFA) levels in erythrocytes are associated with metabolic syndrome (MS). However, the relationship between levels of the VLCFA ligonoceric acid (C24:0) in erythrocytes and the atherogenic lipoprotein profiles and inflammatory state in MS remain unclear. METHODS Based on the International Diabetes Federation (IDF) definition of MS, 195 apparently healthy males were assigned to either an MS group (n=38) or a non-MS group (n=157). Fatty acid composition of erythrocytes was determined by gas liquid chromatography. RESULTS Erythrocytes from the MS group had a significantly higher level of C24:0 than cells from the non-MS group (4.06±0.48% versus 3.88±0.34%; p=0.03). C24:0 levels were significantly correlated with several components of MS. The C24:0 levels showed a significant negative correlation with LDL and HDL particle size. Multivariate linear regression analysis showed that C24:0 levels were independently correlated with LDL particle size after adjusting for age and each MS criterion. C24:0 levels were also positively correlated with log-transformed high-sensitivity CRP levels (p=0.04). CONCLUSION C24:0 levels in erythrocytes are associated with specific atherogenic lipoprotein profiles and inflammation status in subjects with MS.

Clinical significance of the measurements of urinary liver-type fatty acid binding protein levels in patients with acute coronary syndrome

BACKGROUND Recently, much attention has been focused on cardio-renal interaction. Urinary liver-type fatty acid binding protein (U-L-FABP), which is produced in the proximal tubule by renal hypoxia and oxidative stress, has been identified as a useful marker for diagnosis of acute kidney disease and a predictor of future events in chronic kidney disease. However, the clinical significance of U-L-FABP measurements in patients with acute coronary syndrome (ACS) has not been completely evaluated. METHODS AND RESULTS This study included 50 consecutive patients with ACS [37 with acute myocardial infarction (AMI) and 13 with unstable angina pectoris (UAP)] and 47 subjects without coronary artery disease (control group). U-L-FABP levels, urinary albumin (U-Alb), and other serum parameters were measured at admission and at 24 h after percutaneous coronary intervention. RESULTS U-L-FABP levels in patients with AMI were significantly higher (p=0.0019), than in control subjects, while patients with UAP did not exhibit such an increase. U-L-FABP levels at admission were positively correlated with brain natriuretic protein levels (p=0.001) and duration of hospitalization (p=0.025). At follow-up angiography, patients with restenosis had significantly higher U-L-FABP (p=0.047) and U-Alb levels (p<0.0001) than those without restenosis. After a median follow-up of 42 months, U-L-FABP levels at second measurement in patients with major adverse cardiocerebrovascular events (MACCEs) were significantly higher than those in patients without MACCEs (p=0.028). After adjusting for confounding factors, high U-L-FABP levels at second measurement were found to be independent factors for MACCEs (p=0.019). CONCLUSIONS These data suggest that patients with ACS, especially those with AMI, have high U-L-FABP levels, and that U-L-FABP measurements may be useful in identifying high-risk patients for future cardiovascular events after ACS.

Clinical significance of the measurements of plasma N-terminal pro-B-type natriuretic peptide levels in patients with coronary artery disease who have undergone elective drug-eluting stent implantation

BACKGROUND N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a diagnostic biomarker for patients with congestive heart failure (CHF). However, the clinical significance of measurements of NT-proBNP levels in patients with coronary artery disease (CAD) who have undergone drug-eluting stent (DES) implantation has not been fully elucidated. METHODS AND RESULTS We recruited 280 patients with documented CAD who were scheduled for elective coronary intervention and also age- and gender-matched 140 healthy subjects. Subjects with acute coronary syndrome, ongoing CHF, and stage IV or V chronic kidney disease were excluded. We measured the plasma NT-proBNP levels and followed the CAD patients who have undergone DES implantation for up to 62 months until occurrence of major adverse cardiovascular events (MACE). Plasma NT-proBNP levels were significantly higher in CAD patients compared to control subjects (p<0.0001). In the CAD group, 25 patients developed MACE and the NT-proBNP levels in the MACE group were significantly higher compared to that in the non-MACE group (p=0.005). After adjusting for the confounding factors, high NT-proBNP levels were observed to be independent factors for CAD (p<0.0001) and MACE (p=0.021). CONCLUSIONS These results demonstrated that the measurements of NT-proBNP levels may be useful in identifying high-risk subjects among CAD patients who have undergone elective DES implantation.

P-213 Clinical Usefulness of Novel Device Utilizing Fingertip Peripheral Arterial Tomometry in Patients with Coronary Artery Disease

Velocity (baPWV) and conventional coronary risk factors. The relationship between this new parameter and coronary artery sclerosis was evaluated in comparison with other indexes. Results: CAD patients were characteristic of more hypertensive and diabetic with higher CAVI and baPWV than nonCAD subjects. Multivariate logistic analysis after adjustment for hypertension, diabetes mellitus, Dyslipidemia, current smoke, sex and age, still verified that CAD risk was significantly related to CAVI (OR; 3.60, for the difference between the first and the fourth quartile [95% Confidence Interval; 1.60 8.10, p = 0.002]), whereas the same relationship with baPWV statistically diminished (OR; 1.99, 95% Confidence Interval; 0.88 4.49, p = 0.097). CAVI also showed a more remarkable ability to predict CAD than baPWV and age among patients without hypertension and diabetes mellitus under age of 70 (CAVI; OR = 3.98, p = 0.020, baPWV; OR = 0.90, p = 0.631, age; OR = 1.15, p = 0.043). Conclusions: CAVI is more useful in predicting coronary artery stenosis than baPWV in all CAD-suspected subjects and even in their relative low-risk groups, which may lead to a possibility of CAVI for helping detecting CAD among those who are not easily screened out by coronary risk factors and baPWV.