NDP52 interacts with mitochondrial RNA poly(A) polymerase to promote mitophagy.

Parkin-mediated mitophagy is a quality control pathway that selectively removes damaged mitochondria via the autophagic machinery. Autophagic receptors, which interact with ubiquitin and Atg8 family proteins, contribute to the recognition of damaged mitochondria by autophagosomes. NDP52, an autophagy receptor, is required for autophagic engulfment of damaged mitochondria during mitochondrial uncoupler treatment. The N-terminal SKICH domain and C-terminal zinc finger motif of NDP52 are both required for its function in mitophagy. While the zinc finger motif contributes to poly-ubiquitin binding, the function of the SKICH domain remains unclear. Here, we show that NDP52 interacts with mitochondrial RNA poly(A) polymerase (MTPAP) via the SKICH domain. During mitophagy, NDP52 invades depolarized mitochondria and interacts with MTPAP dependent on the proteasome but independent of ubiquitin binding. Loss of MTPAP reduces NDP52-mediated mitophagy, and the NDP52-MTPAP complex attracts more LC3 than NDP52 alone. These results indicate that NDP52 and MTPAP form an autophagy receptor complex, which enhances autophagic elimination of damaged mitochondria.

Ethambutol neutralizes lysosomes and causes lysosomal zinc accumulation.

Ethambutol is a common medicine used for the treatment of tuberculosis, which can have serious side effects, such as retinal and liver dysfunction. Although ethambutol has been reported to impair autophagic flux in rat retinal cells, the precise molecular mechanism remains unclear. Using various mammalian cell lines, we showed that ethambutol accumulated in autophagosomes and vacuolated lysosomes, with marked Zn(2+) accumulation. The enlarged lysosomes were neutralized and were infiltrated with Zn(2+) accumulations in the lysosomes, with simultaneous loss of acidification. These results suggest that EB neutralizes lysosomes leading to insufficient autophagy, implying that some of the adverse effects associated with EB in various organs may be of this mechanism.

Synergistic effects of calcium-channel and angiotensin-receptor blockers on endothelial function and inflammatory responses in a porcine drug-eluting stent model.

BACKGROUND: The rate of stent thrombosis is increased in association with drug-eluting stents (DES) due to delayed endothelialization and prolonged inflammation. Clinical studies have shown that either an angiotensin-receptor blocker (ARB) or a calcium-channel blocker (CCB) can improve endothelial dysfunction and inhibit inflammatory reactions in patients with hypertension. The effects of co-administered CCB and ARB on vascular protection after DES implantation, however, remain unknown. METHODS AND RESULTS: Pigs (n=24) were implanted with coronary stents and randomly assigned to control, CCB, ARB or CCB + ARB groups. Endothelium-mediated vasodilation at the distal edge was significantly impaired compared to the intact site in the control group (P<0.05), but the difference between two sites in the CCB + ARB group was not significant. The combination produced a synergistic effect at the distal edge compared to the ARB, CCB and control groups (P<0.05). The expression of tumor necrosis factor-alpha and inflammatory cell adhesion were significantly inhibited in the CCB or ARB monotherapy groups compared with the control (P<0.05). The combination of CCB + ARB also improved inflammation. CONCLUSIONS: Implanted DES exert adverse effects such as endothelial dysfunction and inflammatory reactions. The administration of either a CCB or an ARB reversed this adverse effect. Furthermore, recovery was synergistically enhanced by a CCB combined with an ARB.

Single administration of alpha-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 alpha-glucosidase inhibitors (alpha-GIs) is associated with a risk reduction of cardiovascular diseases, but the post-prandial effects of alpha-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).

Effects of fenofibrate on lipid profiles, cholesterol ester transfer activity, and in-stent intimal hyperplasia in patients after elective coronary stenting.

BACKGROUND: The association between modulation of detailed lipoprotein profiles and cholesterol ester transfer (CET) activity by peroxisome proliferator-activated receptor (PPAR)-a agonists in patients with coronary artery disease remains unclear. We assessed lipid profiles, plasma CET activity, and in-stent intimal hyperplasia after fenofibrate treatment in patients who underwent elective coronary stenting. METHODS: Forty-three consecutive patients who underwent elective coronary stenting were randomized to the fenofibrate group (300 mg/day for 25 weeks, n = 22) or the control group (n = 21). At baseline and follow up, CET activity and lipoprotein profiles were measured, and quantitative coronary angiography was performed. RESULTS: In the fenofibrate group, the levels of large very low-density lipoprotein cholesterol, and small low-density lipoprotein (LDL) cholesterol decreased and those of small high-density lipoprotein (HDL) cholesterol increased. Besides, CET activity decreased independent of the effect of fenofibrate on total and LDL cholesterol. The reduction of CET activity significantly correlated with the increase in LDL particle size (r = 0.47, P = 0.03) and the decrease of triglycerides in large HDL subclasses (r = 0.48, P = 0.03). Although there were no significant differences in restenosis parameters between the two groups, low CET activity significantly correlated with the inhibition of neointimal hyperplasia (r = 0.56, P = 0.01). CONCLUSIONS: Fenofibrate inhibited CET activity and thereby improved atherogenic lipoprotein profiles, and reduced intimal hyperplasia after coronary stenting.

Presence of alpha-smooth muscle actin-positive endothelial cells in the luminal surface of adult aorta.

Alpha-smooth muscle actin-positive endothelial cells have not been found in adult aortic endothelium except valve leaflets. Here, using en face immunostaining method, we identified alpha-smooth muscle actin-positive endothelial cells in the luminal surface of rat, mouse and human thoracic aortas. These cells express both endothelial markers and definite smooth muscle cell markers and were only occasionally observed in thoracic aorta of wild type mice and rats. Their density did not increase with aging. Given that alpha-smooth muscle actin-positive endothelial cells express low level of vascular endothelial-cadherin that is important for the maintenance of cell contact, these cells were frequently detected in the thoracic aorta of 5-week-old apolipoprotein-E deficient mice. In 20- to 24-week-old apolipoprotein-E deficient mice, marked accumulation of alpha-smooth muscle actin-positive endothelial cells was observed especially in the luminal surface of atheromatous plaques. Our findings indicate the existence of alpha-smooth muscle actin-positive endothelial cells in adult aortic endothelium and the possible association with progression of atherosclerosis.

Insulin response to oral glucose load is associated with coronary artery disease in subjects with normal glucose tolerance.

AIM: The critical role of hyperinsulinemia, independent of hyperglycemia, in the pathogenesis of atherosclerosis has not been fully determined. We investigated the association between secretion patterns of insulin after oral glucose load and the severity of coronary artery disease (CAD) in patients with normal glucose tolerance (NGT). METHODS: We enrolled 116 subjects with NGT from 243 patients who had undergone coronary angiography and a standard 75-g oral glucose tolerance test. The patients were divided into 0-vessel, single-vessel and multi-vessel disease groups on the basis of the severity of CAD. RESULTS: The 2-h insulin levels in the multi-vessel disease group (p=0.005) and the single-vessel disease group (p<0.05) were significantly higher than those in the 0-vessel disease group. Multivariate analysis revealed that the levels of 2-h insulin were an independent variable for the presence of CAD (p=0.02) after adjustment for gender and the presence of each criterion of metabolic syndrome using the definition of the International Diabetes Federation. CONCLUSION: A slight but significant increase in prolonged insulin secretion, which is associated with the early stage of insulin resistance, in subjects with NGT, may play an important role in the pathogenesis of atherosclerosis.

Enhanced production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in very long chain saturated fatty acid-accumulated macrophages.

BACKGROUND: Deterioration of peroxisomal beta-oxidation activity causes an accumulation of very long chain saturated fatty acids (VLCSFA) in various organs. We have recently reported that the levels of VLCSFA in the plasma and/or membranes of blood cells were significantly higher in patients with metabolic syndrome and in patients with coronary artery disease than the controls. The aim of the present study is to investigate the effect of VLCSFA accumulation on inflammatory and oxidative responses in VLCSFA-accumulated macrophages derived from X-linked adrenoleukodystrophy (X-ALD) protein (ALDP)-deficient mice. RESULTS: Elevated levels of VLCSFA were confirmed in macrophages from ALDP-deficient mice. The levels of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma), intracellular reactive oxygen species (ROS), and pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha), interluekin-6 (IL-6), and interleukin-12p70 (IL-12p70), were significantly higher in macrophages from ALDP-deficient mice than in those from wild-type mice. The inducible NO synthase (iNOS) mRNA expression also showed an increase in macrophages from ALDP-deficient mice. CONCLUSION: These results suggested that VLCSFA accumulation in macrophages may contribute to the pathogenesis of inflammatory diseases through the enhancement of inflammatory and oxidative responses.

Immunocytochemical Monitoring of PINK1/Parkin-Mediated Mitophagy in Cultured Cells.

Both PINK1 and parkin are the responsible genes (PARK6 and PARK2, respectively) for familial early-onset Parkinson's disease (PD). Several lines of evidences have suggested that mitochondrial dysfunction would be associated with PD pathogenesis. Lewy body, one of PD pathological hallmarks, contains alpha-synuclein, a familial PD (PARK1/4)-gene product, which is eliminated by macroautophagy, while PINK1 and parkin coordinately mediate mitophagy (hereafter called as PINK1/parkin-mediated mitophagy) reported firstly by Youle's group. The mitochondrial quality control system is specific for elimination of damaged mitochondria especially in the loss of mitochondrial membrane potential induced by treatment with mitochondrial uncoupler like CCCP or FCCP. In this chapter, we summarized immunocytochemical methods to monitor the PINK1/parkin-mediated mitophagy using cultured cells.

Correlation of Nutritional Indices on Admission to the Coronary Intensive Care Unit with the Development of Delirium.

BACKGROUND: Delirium is a common occurrence in patients admitted to the intensive care unit and is related to mortality and morbidity. Malnutrition is a predisposing factor for the development of delirium. Nevertheless, whether the nutritional status on admission anticipates the development of delirium in patients with acute cardiovascular diseases remains unknown. OBJECTIVE: This study aims to assess the correlation between the nutritional status on admission using the nutritional index and the development of delirium in the coronary intensive care unit. DESIGN: We examined 653 consecutive patients (mean age: 70 ± 14 years) admitted to the coronary intensive care unit of Juntendo University Hospital between January 2015 and December 2016. We evaluated three nutritional indices frequently used to assess the nutritional status, i.e., Geriatric Nutritional Risk Index (GNRI), Prognostic Nutritional Index (PNI), and Controlling Nutritional Status (CONUT). We defined delirium as patients with a delirium score >4 using the Intensive Care Delirium Screening Checklist. RESULTS: Delirium was present in 58 patients. All nutritional indices exhibited a tendency for malnutrition in the delirium group compared with the non-delirium group (GNRI, 86.5 ± 9.38 versus 91.6 ± 9.89; PNI, 36.4 ± 6.95 versus 41.6 ± 7.62; CONUT, 5.88 ± 3.00 versus 3.61 ± 2.56; for all, p < 0.001). Furthermore, the maximum delirium score increased progressively from the low- to the high-risk group, as evaluated by each nutritional index (GNRI, PNI, CONUT; for all, p < 0.001). A multivariate analysis revealed that the PNI and CONUT were independent risk factors for the occurrence of delirium. CONCLUSIONS: A marked correlation exists between the nutritional index on admission, especially PNI and CONUT, and the development of delirium in patients with acute cardiovascular diseases, suggesting that malnutrition assessment upon admission could help identify patients at high risk of developing delirium.

Dynamin-2 regulates oxidized low-density lipoprotein-induced apoptosis of vascular smooth muscle cell.

BACKGROUND: On exposure to oxidized low-density lipoprotein (oxLDL), vascular cells generally undergo apoptosis, which is one of the major pathogenic factors of atherosclerosis. In this study, we examined the role of dynamin (a crucial GTPase protein in endocytosis) in oxLDL-induced apoptosis of vascular smooth muscle cells (VSMC). METHODS AND RESULTS: After oxLDL stimulation, dynamin-2 colocalized with LOX-1 around the cell surface, as well as oxLDL in the cytoplasm, suggesting that dynamin-2 was involved in scavenger receptor-mediated oxLDL endocytosis. Downregulation of dynamin-2 induced by dynamin-2 dominant negative plasmid (K44A) resulted in a decrease of oxLDL uptake and thereby in a reduction of apoptosis. These data demonstrated that dynamin-2 was involved in oxLDL-induced apoptosis via the oxLDL endocytotic pathway. On the other hand, dynamin-2 wild-type plasmid transfection promoted oxLDL-induced apoptosis without increasing oxLDL uptake. Interestingly, the p53 inhibitor pifithrin-alpha (PFT) significantly reduced apoptosis promoted by wild-type dynamin-2 (78% reduction compared with the PFT[-] condition). These results indicated that dynamin-2 enhanced oxLDL-induced apoptosis of VSMC by participating in the p53 pathway, probably as a signal transducer. Moreover, we demonstrated that, in advanced plaques of apolipoprotein E-/- mice, dynamin-2 expression was often enhanced in apoptotic VSMC, suggesting that dynamin-2 might participate in apoptosis of VSMC even in vivo. CONCLUSIONS: Our data demonstrated that dynamin-2 at least partially regulated oxLDL-induced apoptosis of VSMC by participating in 2 independent pathways: the oxLDL endocytotic pathway and the p53 pathway. These findings suggest that dynamin-2 may serve as a new research or therapeutic target in vascular disease.

Circulating malondialdehyde-modified LDL and atherogenic lipoprotein profiles measured by nuclear magnetic resonance spectroscopy in patients with coronary artery disease.

OBJECTIVE: Recent studies have suggested that circulating malondialdehyde-modified low-density lipoprotein (MDA-LDL) is a useful marker for the identification of patients with coronary artery disease (CAD). However, the role of MDA-LDL in atherogenic mechanisms has not yet been fully determined. METHOD AND RESULTS: We investigated lipoprotein profiles measured by nuclear magnetic resonance (NMR) spectroscopy and circulating MDA-LDL levels measured by ELISA in 25 male patients with CAD and 15 age-matched male controls. We selected subjects who had a serum LDL cholesterol<160 mg/dL. The MDA-LDL levels were significantly higher in the CAD group than in the control group (P=0.01) even though there was no significant difference in the LDL cholesterol levels between the two groups. NMR analysis demonstrated that the MDA-LDL levels were positively correlated with large and intermediate very low-density lipoprotein triglyceride and LDL particle concentrations, and negatively correlated with LDL diameter and large high-density lipoprotein cholesterol. The MDA-LDL levels were negatively correlated with flow-mediated dilatation of the brachial artery. CONCLUSIONS: The high concentrations of circulating MDA-LDL derived from the atherogenic lipoprotein profiles, which induce the exaggerated production of small dense LDL. The circulating MDA-LDL may impair endothelial function and play an important role in the pathogenesis of atherosclerosis.

Circulating oxidized low-density lipoprotein is an independent predictor for cardiac event in patients with coronary artery disease.

Oxidized low-density lipoprotein (oxLDL) plays a crucial role in the development of atherosclerosis, however, the predictive value of circulating oxLDL for cardiac events (CE) in patients with coronary artery disease (CAD) has remained poorly understood. We prospectively studied 238 consecutive patients with documented CAD for up to 52 months until the occurrence of one of the following cardiac events: cardiac death, nonfatal myocardial infarction (MI), and refractory angina requiring revascularization. The plasma levels of oxLDL were measured by an enzyme-linked immunosorbent assay (ELISA) using the monoclonal antibody, DLH3. The levels of circulating oxLDL were significantly higher in patients with CE than in patients without CE (median 20.3 U/ml versus 17.6 U/ml, P = 0.002). Multivariate Cox models showed that higher level of oxLDL was an independent predictor of developing CE. The adjusted hazard ratios for CE were 3.15 (95% CI 1.47-6.76, P = 0.003) times higher in patients with the highest quartile of oxLDL levels and 1.88 (95% CI 0.90-3.95, P = 0.09) times higher in patients with the third quartile than in those within the lowest quartile. Thus, measurement of circulating oxLDL may be helpful in the assessment of future CE in patients with CAD.

The high molecular weight adiponectin level is associated with the atherogenic lipoprotein profiles in healthy Japanese males.

AIM: Circulating adiponectin comprises high, medium and low molecular weight (HMW, MMW, and LMW) forms. Decreased adiponectin levels have been demonstrated to correlate with the atherogenic lipoprotein profile in patients with metabolic syndrome(MS). However, the associations of these isoforms with the atherogenic lipoprotein profiles in the healthy population remain unclear. METHODS: Apparently healthy male subjects were divided into non-MS(n=132) and MS(n=63) groups. We measured the total, HMW, MMW and LMW adiponectin levels by ELISA, and determined the detailed lipoprotein profiles by high-performance liquid chromatography. RESULTS: The total and HMW adiponectin levels in the MS group were significantly lower than those in the non-MS group(3.8±1.9 vs. 4.9±2.4µg/mL, p＜0.001 and 1.6±1.2 vs. 2.5±1.9µg/mL, p＜0.001, respectively), whereas the MMW and LMW levels did not differ significantly between the groups. The total and HMW adiponectin levels correlated with the atherogenic lipoprotein profiles, including the following: 1) increased cholesterol levels in the small LDL subclasses; 2) decreased cholesterol levels in the larger HDL subclasses; 3) increased triglycerides(TGs) in almost all VLDL and LDL subclasses and 4) decreased TGs in the large HDL and increased TGs in the small HDL subclasses. In addition, a multivariate analysis demonstrated that the HMW adiponectin level was an independent predictor of the small LDL and HDL levels(p=0.02 for both). CONCLUSIONS: The HMW, but not MMW or LMW, adiponectin levels are associated with the typical atherogenic lipoprotein profiles, independent of MS components. Measurement of the HMW adiponectin levels could be useful for identifying the atherogenicity in apparently healthy males.

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-ß 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.

Voluntary exercise ameliorates the progression of atherosclerotic lesion formation via anti-inflammatory effects in apolipoprotein E-deficient mice.

AIM: A sedentary lifestyle with insufficient exercise is associated with cardiovascular disease. Previous studies have demonstrated that endurance exercise benefits atherosclerosis and cardiovascular disorders; however, the mechanisms by which physical activity, such as voluntary exercise (Ex), produces these effects are not fully understood. METHODS AND RESULTS: Eight-week-old male apolipoprotein (ApoE)-deficient mice were fed a standard diet (STD) or high fat diet (HFD) for 10 weeks. The HFD+Ex group mice performed Ex on a running wheel for 10 weeks. No significant differences in lipid profiles were observed between the HFD and HFD+Ex groups. Although changes in body and brown adipose tissue weights were comparable between the HFD and HFD+Ex groups, white adipose tissue weight was significantly lower in the HFD+Ex group than in the HFD group. The areas of atherosclerotic lesions in the aortic sinus and thoracoabdominal aorta were significantly reduced in the HFD+Ex group than in the HFD group (p<0.001). There was a strong negative correlation between atherosclerotic areas and the mean running distance per day in the HFD+Ex group (r=-0.90, p=0.01). Endothelial function was significantly preserved in the HFD+Ex group (p<0.05). Serum interleukin-6 and macrophage chemoattractant protein-1 levels were significantly lower and those of adiponectin were significantly higher in the HFD+Ex group than in the HFD group (p<0.05). CONCLUSIONS: These results suggest that Ex ameliorates the progression of endothelial dysfunction and atherosclerotic lesion formation through anti-inflammatory effects, despite continued consumption of HFD.

Polyunsaturated fatty acid levels of serum and red blood cells in apparently healthy Japanese subjects living in an urban area.

AIM: We assessed levels of polyunsaturated fatty acid (PUFA) in serum and red blood cells (RBCs) among groups stratified by generation and its clinical significance in Japanese subjects living in an urban area. METHODS: We enrolled 200 apparently healthy Japanese (126 males, mean age: 50.3+/-9.2 years) living in an urban area. Levels of PUFA, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), and dihomo-gamma-linolenic acid (DGLA) in serum and RBCs were measured for each generation (G1 <35y, G2 35y-<45y, G3 45y-<55y, G4 55y-<65y, G5>or=65y). RESULTS: No significant differences in EPA, DHA, AA, or EPA/AA were observed between males and females. After dividing into generations, stepwise increases in EPA and DHA, but not DGLA or AA, were observed in serum (all p<0.0001). EPA/AA ratios were stepwisely increased in serum (mean: G1:0.26, G2:0.29, G3:0.43, G4:0.58, G5:0.68, p<0.0001) and RBCs (mean: G1:0.10, G2:0.09, G3:0.15, G4:0.20, G5:0.23, p<0.0001). Positive correlations of EPA (r=0.83), DHA (r=0.55), DGLA (r=0.54), AA (r=0.29), and EPA/AA (r=0.91) were demonstrated between serum and RBCs. In addition, a significant positive correlation between EPA/AA ratios and insulin sensitivity as well as a negative correlation between those ratios and insulin resistance were observed in subjects with metabolic syndrome. CONCLUSION: Low levels of EPA/AA, which were associated with insulin resistance, were demonstrated in young Japanese adults living in an urban area.

Skeletonization with an ultrasonic scalpel is as safe as a non-skeletonized dissection in preserving the endothelial function of the human gastroepiploic artery.

The right gastroepiploic artery (GEA) is frequently used as another in situ artery, other than the internal thoracic artery (ITA) in coronary artery bypass grafting (CABG). Skeletonizing the graft with an ultrasonic scalpel is now regarded as a useful technique; however, this technique may damage the endothelial function during harvesting the graft resulting in postoperative graft stenosis or occlusion. In the present study, GEA segments from nine patients were excised in both a skeletonized and non-skeletonized manner with an ultrasonic scalpel, and then were transported to the laboratory. The vessels were trimmed as rings, and were allotted to the group of skeletonized or non-skeletonized, accordingly. The force development in response to 1 mumol/l norepinephrine did not differ between the skeletonized and non-skeletonized groups. Endothelium-dependent relaxation induced by either acetylcholine or bradykinin was not impaired in the skeletonized group in comparison to the non-skeletonized group. No significant difference was observed in endothelium-independent relaxation elicited by sodium nitroprusside. Therefore, the skeletonization of the GEA with an ultrasonic scalpel was thus found to be as safe as a non-skeletonized dissection in preserving the vascular contractile ability or endothelium-dependent and -independent relaxation of the graft.

Serum levels of remnant lipoprotein cholesterol and oxidized low-density lipoprotein in patients with coronary artery disease.

BACKGROUND: Oxidized low-density lipoprotein (OxLDL) and remnant lipoprotein play a crucial role in the development of atherosclerosis. Recently, a novel method for measuring remnant cholesterol levels (remnant lipoproteins cholesterol homogenous assay: RemL-C) has been established. However, the correlation between OxLDL and remnant lipoprotein, including RemL-C, has not been fully investigated. METHODS: We enrolled 25 consecutive patients with documented coronary artery disease (CAD) and 20 controls. Remnant-like particle cholesterol (RLP-C) and RemL-C were used to determine the levels of remnant lipoprotein cholesterol. Serum levels of malondialdehyde-modified LDL (MDA-LDL) and OxLDL using a monoclonal antibody DLH3 (OxPC) were used to measure the concentration of circulating OxLDL. RESULTS: The CAD group had high levels of fasting glucose and glycosylated hemoglobin (HbA1c), and low levels of high-density lipoprotein cholesterol compared with the control group. Serum levels of total cholesterol or LDL cholesterol were not significantly different between the two groups. The levels of RemL-C (p = 0.035), MDA-LDL (p = 0.018), and MDA-LDL/LDL-C (p = 0.036) in the CAD group were significantly higher than those in the control group. The levels of RLP-C tended to be higher in the CAD group than those in the control group (p = 0.096). Positive correlations were demonstrated between remnant lipoprotein cholesterol and OxLDL (RLP-C and MDA-LDL/LDL-C, r = 0.45, p = 0.0024, RLP-C and OxPC, r = 0.51, p = 0.0005, RemL-C and MDA-LDL/LDL-C, r = 0.42, p = 0.0044, RemL-C and OxPC, r = 0.43, p = 0.0043). Similar trends were observed in non-diabetic subjects and in subjects without metabolic syndrome. Positive correlations were also observed between RLP-C and RemL-C (r = 0.94, p < 0.0001) and between MDA-LDL/LDL-C and OxPC (r = 0.40, p = 0.0074). CONCLUSIONS: These results suggest that the association between high levels of remnant lipoprotein cholesterol and high OxLDL levels might be linked to atherogenesis in patients with CAD.