Heme oxygenase is a rate-limiting enzyme in heme degradation, leading to the generation of free iron, biliverdin, and carbon monoxide. Induction of heme oxygenase-1 is implicated in the antioxidant defense mechanism and can modulate vascular function. To test the association of microsatellite polymorphism in the promoter region of human HO-1 gene with the risk of coronary artery disease (CAD) in type 2 diabetic patients, we examined the allele frequencies of (GT) (n) repeats in HO-1 gene in 474 patients with CAD and in 322 controls. A transient-transfection assay with HO-1 promoter/luciferase fusion constructs carrying various lengths of (GT) (n) repeats was performed to explore the regulatory effect of (GT) (n) repeats on HO-1 gene expression in cultured rat aortic smooth muscle cells. Serum thiobarbituric acid-reactive substances (TBARs), a measure of lipid peroxidation, was significantly higher in subjects carrying the L/L genotype (> or =32 repeats). Among type 2 diabetic subjects, the frequencies of the L alleles and proportion of genotypes with L alleles were significantly higher in those with CAD than in those without CAD. The adjusted odds ratio for CAD in type 2 diabetic patients with L alleles was 4.7 (95% confidence interval, 1.9-12.0, P=0.001). Transfection experiments in aortic smooth muscle cells revealed that HO-1 promoter/luciferase fusion constructs containing longer (GT) (n) repeats exhibited lower transcriptional activity. These results imply that the length polymorphism in the HO-1 gene promoter modulate the transcription of the gene in vascular cells. Type 2 diabetics carrying longer (GT) (n) repeats might have higher oxidative stress and increased susceptibility to the development of CAD.
It has been speculated that before vertebrates evolved somatic diversity-based adaptive immunity, the germline-encoded diversity of innate immunity may have been more developed. Amphioxus occupies the basal position of the chordate phylum and hence is an important reference to the evolution of vertebrate immunity. Here we report the first comprehensive genomic survey of the immune gene repertoire of the amphioxus Branchiostoma floridae. It has been reported that the purple sea urchin has a vastly expanded innate receptor repertoire not previously seen in other species, which includes 222 toll-like receptors (TLRs), 203 NOD/NALP-like receptors (NLRs), and 218 scavenger receptors (SRs). We discovered that the amphioxus genome contains comparable expansion with 71 TLR gene models, 118 NLR models, and 270 SR models. Amphioxus also expands other receptor-like families, including 1215 C-type lectin models, 240 LRR and IGcam-containing models, 1363 other LRR-containing models, 75 C1q-like models, 98 ficolin-like models, and hundreds of models containing complement-related domains. The expansion is not restricted to receptors but is likely to extend to intermediate signal transducers because there are 58 TIR adapter-like models, 36 TRAF models, 44 initiator caspase models, and 541 death-fold domain-containing models in the genome. Amphioxus also has a sophisticated TNF system and a complicated complement system not previously seen in other invertebrates. Besides the increase of gene number, domain combinations of immune proteins are also increased. Altogether, this survey suggests that the amphioxus, a species without vertebrate-type adaptive immunity, holds extraordinary innate complexity and diversity.
OBJECTIVE-Endothelial progenitor cells (EPCs) are impaired in diabetes. This study aimed to investigate the direct effects of high glucose on EPCs.RESEARCH DESIGN AND METHODS-Mononuclear cells isolated from healthy subjects were incubated with glucose/ mannitol or drugs for EPC study. After 4 days of culture, attached early EPCs appeared. The monolayer late EPCs with cobblestone shape appeared at 2-4 weeks. Various immunofluroscence stainings were used to characterize the early and late EPCs. Senescence assay and the activity of endothelial nitric oxide synthase (eNOS) were determined. Migration and tube formation assay were done to evaluate the capacity for vasculogenesis in late EPCs.RESULTS-Chronic incubation with high glucose but not mannitol (osmotic control) dose-dependently reduced the number and proliferation of early and late EPCs, respectively. High glucose enhanced EPC senescence and impaired the migration and tube formation of late EPCs. High glucose also decreased eNOS, FoxO1, and Akt phosphorylation and bioavailable nitric oxide (NO) in both EPCs. The effects of high glucose could be ameliorated by coincubation with NO donor sodium nitroprusside or p38 mitogen-activated protein kinase inhibitor and deteriorated by eNOS inhibitor or PI3K (phosphatidylinositol 3Ј-kinase) inhibitor. Antioxidants including vitamin C, N-acetylcysteine-and polyethylene glycol (PEG)-conjugated superoxide dismutase, and PEG-catalase had no effects, whereas pyrrolidine dithiocarbamate, diphenyleneiodonium, apocynin, and rotenone even deteriorated the downregulation of both EPCs. CONCLUSIONS-High
Background: This study examines the predictive value of a novel systemic immuneinflammation index (SII, platelet × neutrophil/lymphocyte ratio) in coronary artery disease (CAD) patients. Methods: A total of 5602 CAD patients who had undergone a percutaneous coronary intervention (PCI) were enrolled. They were divided into two groups by baseline SII score (high SII vs low SII) to analyse the relationship between SII groups and the long-term outcome. The primary outcomes were major cardiovascular events (MACE) which includes nonfatal myocardial infarction (MI), nonfatal stroke and cardiac death. Secondary outcomes included a composite of MACE and hospitalization for congestive heart failure. Results: An optimal SII cut-off point of 694.3 × 10 9 was identified for MACE in the CAD training cohort (n = 373) and then verified in the second larger CAD cohort (n = 5602). Univariate and multivariate analyses showed that a higher SII score (≥694.3) was independently associated with increased risk of developing cardiac death (HR: 2.02; 95% CI: 1.43-2.86), nonfatal MI (HR: 1.42; 95% CI: 1.09-1.85), nonfatal stroke (HR: 1.96; 95% CI: 1.28-2.99), MACE (HR: 1.65; 95% CI: 1.36-2.01) and total major events (HR: 1.53; 95% CI: 1.32-1.77). In addition, the SII significantly improved risk stratification of MI, cardiac death, heart failure, MACE and total major events than conventional risk factors in CAD patients by the significant increase in the C-index (P < .001) and reclassification risk categories by significant NRI (P < .05) and IDI (P < .05). Conclusions: SII had a better prediction of major cardiovascular events than traditional risk factors in CAD patients after coronary intervention. K E Y W O R D Scoronary artery disease, inflammation, percutaneous coronary intervention 2 of 11 | YANG et Al.
Objective-Both matrix metalloproteinases (MMPs) and endothelial progenitor cells (EPCs) have been implicated in the process of neovascularization. Here we show that the impaired neovascularization in mice lacking MMP-9 is related to a defect in EPC functions in vasculogenesis. Methods and Results-Hindlimb ischemia surgery was conducted in MMP-9 Ϫ/Ϫ mice and wild-type (MMP-9 ϩ/ϩ ) mice. Blood flow recovery was markedly impaired in MMP-9 Ϫ/Ϫ mice when compared with that in wild-type mice as determined by laser Doppler imaging. Flow cytometry demonstrated that the number of EPC-like cells (Sca-1 ϩ /Flk-1 ϩ ) in peripheral blood increased in wild-type mice after hindlimb ischemia surgery and exogenous vascular endothelial growth factor stimulation, but not in MMP-9 Ϫ/Ϫ mice. Plasma levels and bone marrow concentrations of soluble Kit-ligand (sKitL) were significantly elevated in wild-type mice in response to tissue ischemia, but not in MMP-9 Ϫ/Ϫ mice. C-kit positive bone marrow cells of MMP-9 Ϫ/Ϫ mice have attenuated adhesion and migration than those isolated from wild-type mice. In in vitro studies, incubation with selective MMP-9 inhibitor suppressed the colony formation, migration, and tube formation capacities of EPC. Transplantation of bone marrow cells from wild-type mice restored collateral flow formation in MMP-9 Ϫ/Ϫ mice. Conclusions-These findings suggest that MMP-9 deficiency impairs ischemia-induced neovascularization, and these effects may occur through a reduction in releasing the stem cell-active cytokine, and EPC mobilization, migration, and vasculogenesis functions.
Objective-Red wine (RW) consumption has been associated with a reduction of cardiovascular events, but limited data are available on potential mediating mechanisms. This study tested the hypothesis that intake of RW may promote the circulating endothelial progenitor cell (EPC) level and function through enhancement of nitric oxide bioavailability. Methods and Results-Eighty healthy, young subjects were randomized and assigned to consume water (100 mL), RW (100 mL), beer (250 mL), or vodka (30 mL) daily for 3 weeks. Flow cytometry was used to quantify circulating EPC numbers, and in vitro assays were used to evaluate EPC functions. After RW ingestion, endothelial function determined by flow-mediated vasodilation was significantly enhanced; however, it remained unchanged after water, beer, or vodka intake. There were significantly increased numbers of circulating EPC (defined as) and EPC colony-forming units only in the RW group (all PϽ0.05). Only RW ingestion significantly enhanced plasma levels of nitric oxide and decreased asymmetrical dimethylarginine (both PϽ0.01). Incubation of EPC with RW (but not beer or ethanol) and resveratrol in vitro attenuated tumor necrosis factor-␣-induced EPC senescence and improved tumor necrosis factor-␣-suppressed EPC functions and tube formation. Incubation with nitric oxide donor sodium nitroprusside significantly ameliorated the inhibition of tumor necrosis factor-␣ on EPC proliferation, but incubation with endothelial nitric oxide synthase inhibitor L-NAME and PI3K inhibitor markedly attenuated the effect of RW on EPC proliferation. Conclusion-The intake of RW significantly enhanced circulating EPC levels and improved EPC functions by modifying nitric oxide bioavailability. These findings may help explain the beneficial effects of RW on the cardiovascular system. This study demonstrated that a moderate intake of RW can enhance circulating levels of EPC in healthy subjects by increasing nitric oxide availability. Direct incubation of EPC with RW and resveratrol can modify the functions of EPC, including attenuation of senescence and promotion of EPC adhesion, migration, and tube formation. These data suggest that RW ingestion may alter the biology of EPC, and these alterations may contribute to its unique cardiovascularprotective effect. (Arterioscler Thromb Vasc Biol. 2010;30:869-877.)
To investigate the evolution and immune function of C-type lectin in amphioxus, the primitive representative of the chordate phylum, we identified three C-type lectins consisting solely of a carbohydrate recognition domain and N-terminal signal peptide and found that they had distinct express patterns in special tissues and immune response to stimulations analyzed by quantitative real-time PCR. We characterized the biochemical and biological properties of AmphiCTL1, which was dramatically up-regulated in amphioxus challenged with Staphylococcus aureus, Saccharomyces cerevisiae, and zymosan. Immunohistochemistry demonstrated that the localization of AmphiCTL1 protein was exclusively detected in the inner folding tissues of the hepatic diverticulum. Recombinant AmphiCTL1 was characterized as a typical Ca2+-dependent carbohydrate-binding protein possessing hemagglutinating activity, preferentially bound to all examined four Gram-positive bacteria and two yeast strains, but had little binding activity toward four Gram-negative bacteria we tested. It aggregated S. aureus and S. cerevisiae in a Ca2+-dependent manner and specifically bound to insoluble peptidoglycan and glucan, but not to LPS, lipoteichoic acid, and mannan. Calcium increased the intensity of the interaction between AmphiCTL1 and those components, but was not essential. This lectin directly killed S. aureus and S. cerevisiae in a Ca2+-independent fashion, and its binding to microorganism cell wall polysaccharides such as peptidoglycan and glucan preceded microbial killing activity. These findings suggested that AmphiCTL1 acted as a direct microbial killing C-type lectin through binding microbial targets via interaction with peptidoglycan and glucan. Thus, AmphiCTL1 may be an evolutionarily primitive form of antimicrobial protein involved in lectin-mediated innate immunity.
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