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Background & Aims: Secondary prevention can improve outcomes in high risk patients. This study investigated the magnitude of cardiovascular risk reduction associated with consumption of a modified portfolio diet in parallel with medical management., Design: 30 patients with type II diabetes, 6 weeks post bypass surgery received dietary counseling on a Modified Portfolio Diet (MPD) (low fat, 8 g/1000 kcal viscous fibres, 17 g/1000 kcal soy protein and 22 g/1000 kcal almonds). Lipid profiles, endothelial function and markers of glycemic control, oxidative stress and inflammation were measured at baseline and following two and four weeks of intervention. Seven patients with no diet therapy served as time controls., Results: Consumption of the MPD resulted in a 19% relative reduction in LDL (1.9 ± 0.8 vs 1.6 ± 0.6 mmol/L, p < 0.001) with no change in HDL cholesterol. Homocysteine levels dropped significantly (10.1 ± 2.7 vs 7.9 ± 4 μmol/L, p = 0.006) over the study period. Flow mediated dilatation increased significantly in treated patients (3.8 ± 3.8% to 6.5 ± 3.6%, p = 0.004) while remaining constant in controls (p = 0.6). Endothelial progenitor cells numbers (CD34+, CD 133+ and UEA-1+) increased significantly following MPD consumption (p < 0.02) with no difference in migratory capacity. In contrast, time controls showed no significant changes., Conclusion: Dietary intervention in medically managed, high risk patients resulted in important reductions in risk factors. Clinical Trials registry number NCT00462436., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: Perlecan is a heparan sulfate proteoglycan (HSPG) constituent of the extracellular matrix with roles in cell growth, differentiation, and angiogenesis. The role of the HS side chains in regulating in vivo angiogenesis after hind-limb ischemia is unknown., Methods: Heparan sulfate (HS)-deficient perlecan (Hspg2(Δ3/Δ3)) mice (n = 35), containing normal perlecan core protein but deficient in HS side chains, and wild-type (n = 33) littermates underwent surgical induction of hind-limb ischemia. Laser Doppler perfusion imaging (LDPI) and contrast-enhanced ultrasonography (CEU) provided serial assessment of hind-limb perfusion. Harvested muscles underwent immunostaining for endothelial cell density (CD31), real-time reverse transcription polymerase chain reaction RT-PCR for vascular endothelial growth factor (VEGF) mRNA expression and western blot analysis for VEGF and fibroblast growth factor (FGF)2 protein expression at days 2 and 28., Results: Serial LDPI showed significantly greater perfusion recovery in ischemic limbs of wild-type compared with Hspg2(Δ3/Δ3) mice. CEU showed that normalized microvascular perfusion was increased in wild-type compared with Hspg2(Δ3/Δ3) mice at day 28 (0.67 ± 0.12 vs 0.26 ± 0.08; P = 0.001). CD31-positive cell counts were significantly higher in wild-type compared with Hspg2(Δ3/Δ3) mice on day 28 (122 ± 30 cells vs 84 ± 34 cells per high-power field [HPF]; P < 0.05). Endogenous VEGF mRNA expression (P < 0.05) and VEGF protein expression (P < 0.002) were significantly decreased in the ischemic limbs of Hspg2(Δ3/Δ3) mice compared with wild-type mice at day 2 and day 28, respectively. FGF2 protein expression showed no significant differences., Conclusions: These results suggest that the HS side chains in perlecan are important mediators of the angiogenic response to ischemia through a mechanism that involves upregulation of VEGF expression., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Objectives: Diabetes mellitus (DM) is associated with impairment of endothelial progenitor cells (EPCs), but the effects of metabolic syndrome (MS) on EPCs have been less well characterized. We hypothesized that in the presence of MS, the number and functionality of EPCs would be markedly reduced, and would be similar to DM., Methods: Mononuclear cells were isolated from the bone-marrow (BM) and peripheral blood of lean Zucker, obese Zucker, a model of MS, and Zucker diabetic fatty rats. Cultured BM-EPCs underwent in vitro functional testing and the ability of BM-EPCs to promote neovascularization in vivo was assessed in a model of hindlimb ischemia in athymic mice., Results: While circulating EPC numbers were similarly reduced in both MS and DM rats, BM-derived EPC numbers were less affected. In vitro testing of cultured BM-EPCs from obese Zucker demonstrated a marked reduction in EPC differentiation, a greater propensity to apoptosis, a reduced migratory response and matrigel tubule formation, similar to findings in Zucker diabetic fatty rats. When delivered to the ischemic hindlimb of athymic mice, the recovery of perfusion using both BM-EPCs from obese Zucker and Zucker diabetic fatty rats were diminished, as compared to lean Zuckers., Conclusion: In the presence of the MS, BM-derived EPCs develop marked functional impairment, resulting in severely reduced angiogenic capacity in vivo. Similar to DM, EPC dysfunction may play a prominent role in the pathogenesis of vascular complications in the MS, and may potentially limit the use of BM-derived EPCs for therapeutic angiogenesis., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Objectives: Ultrasound-mediated gene delivery can be amplified by acoustic disruption of microbubble carriers that undergo cavitation. We hypothesized that endothelial targeting of microbubbles bearing cDNA is feasible and, through optimizing proximity to the vessel wall, increases the efficacy of gene transfection., Background: Contrast ultrasound-mediated gene delivery is a promising approach for site-specific gene therapy, although there are concerns with the reproducibility of this technique and the safety when using high-power ultrasound., Methods: Cationic lipid-shelled decafluorobutane microbubbles bearing a targeting moiety were prepared and compared with nontargeted microbubbles. Microbubble targeting efficiency to endothelial adhesion molecules (P-selectin or intercellular adhesion molecule [ICAM]-1) was tested using in vitro flow chamber studies, intravital microscopy of tumor necrosis factor-alpha (TNF-α)-stimulated murine cremaster muscle, and targeted contrast ultrasound imaging of P-selectin in a model of murine limb ischemia. Ultrasound-mediated transfection of luciferase reporter plasmid charge coupled to microbubbles in the post-ischemic hindlimb muscle was assessed by in vivo optical imaging., Results: Charge coupling of cDNA to the microbubble surface was not influenced by the presence of targeting ligand, and did not alter the cavitation properties of cationic microbubbles. In flow chamber studies, surface conjugation of cDNA did not affect attachment of targeted microbubbles at microvascular shear stresses (0.6 and 1.5 dyne/cm(2)). Attachment in vivo was also not affected by cDNA according to intravital microscopy observations of venular adhesion of ICAM-1-targeted microbubbles and by ultrasound molecular imaging of P-selectin-targeted microbubbles in the post-ischemic hindlimb in mice. Transfection at the site of high acoustic pressures (1.0 and 1.8 MPa) was similar for control and P-selectin-targeted microbubbles but was associated with vascular rupture and hemorrhage. At 0.6 MPa, there were no adverse bioeffects, and transfection was 5-fold greater with P-selectin-targeted microbubbles., Conclusions: We conclude that ultrasound-mediated transfection at safe acoustic pressures can be markedly augmented by endothelial juxtaposition., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Purpose: The objective of this study was to determine the effects of different doses of gamma-emitting radioactive stents on intimal hyperplasia in a porcine coronary stent model at 28 days., Methods: Sixty-four bare stents and those coated with palladium-103 [activities of 0 (control), 0.5, 1.0, 2.0, and 4.0 mCi] were implanted in the coronary arteries of 32 pigs. Stented segments were evaluated by histomorphometry at 28 days., Results: There was significantly more intima in the 0.5- and 1-mCi stents than in controls (4.27+/-0.52 and 4.71+/-1.13 vs. 1.71+/-0.61 mm(2); P<.0001). Neointimal formation in 2-mCi stents was similar to that in controls, while that in 4-mCi stents was reduced compared to that in controls (2.34+/-1.61 and 0.82+/-0.25 vs. 1.71+/-0.61 mm(2); P=NS and P<.05, respectively). Stent margin neointimal response was representative of that within the stent body, with nonsignficant modest increases in intimal area at adjacent nonstented segments in radioactive stent groups. There was a dose-dependent increase in inflammation scores. Radioactive stents had lower intimal smooth muscle and higher fibrin scores. There was an increase in adventitial fibrosis in 1- and 2-mCi stents versus controls (1.26+/-0.99, and 2.25+/-1.27 vs. 0.21+/-0.31; P<.001)., Conclusion: Dose-response inhibition of in-stent hyperplasia with minimal "edge effects" occurs with low-energy gamma-emitting stents. An increased inflammatory response at higher doses in palladium-103 stents indicates that later follow-up studies are necessary.