Background: High epicardial adipose tissue (EAT) attenuation (Hounsfield units [HUs]) on computed tomography is considered a marker of inflammation and is associated with an increased risk of cardiovascular events. Statins reduce the volume of EAT, but it is unknown whether they affect EAT HUs. Methods and Results: We reviewed the chest computed tomographic scans of 420 postmenopausal women randomized to either 80 mg of atorvastatin or 40 mg of pravastatin daily and rescanned after 1 year to measure change in coronary artery calcium score. EAT HUs were measured near the proximal right coronary artery and remote from any area of coronary artery calcium. Computed tomographic images were also queried for subcutaneous adipose tissue (SubQ) attenuation (HUs) change over time. The mean patients’ age was 65±6 years. The baseline EAT HU value was higher than the SubQ HU value (−89.4±24.0 HU versus −123.3±30.4 HU; P<0.001). The EAT HU value decreased significantly in the entire cohort (−5.4±29.7 HU [−6% change]; P<0.001), but equally in the patients given atorvastatin and pravastatin (−6.35+31 HU and −4.55+28 HU; P=0.55). EAT HU change was not associated with change in total cholesterol, low-density lipoprotein cholesterol, coronary artery calcium, and EAT volume (all P=not significant). Change in high-density lipoprotein cholesterol was marginally associated with EAT HU change (P=0.07). Statin treatment did not induce a change in SubQ HUs. Conclusions: Statins induced a decrease in EAT HUs over time, independent of intensity of low-density lipoprotein cholesterol lowering. The positive effect on EAT and the neutral effect on SubQ suggest that statins induced a decrease in metabolic activity in EAT by reduction in cellularity, vascularity, or inflammation. The clinical significance of the observed change in EAT HUs remains to be demonstrated.
by
Maryam Y. Naim;
Heather M. Griffis;
Rita Burke;
Bryan McNally;
Lihai Song;
Robert A. Berg;
Vinay M. Nadkarni;
Kimberly Vellano;
David Markenson;
Richard N. Bradley;
Joseph W. Rossano
Background: Whether racial and neighborhood characteristics are associated with bystander cardiopulmonary resuscitation (BCPR) in pediatric out-of-hospital cardiac arrest (OHCA) is unknown. Methods and Results: An analysis was conducted of CARES (Cardiac Arrest Registry to Enhance Survival) for pediatric nontraumatic OHCAs from 2013 to 2017. An index (range, 0–4) was created for each arrest based on neighborhood characteristics associated with low BCPR (>80% black; >10% unemployment; <80% high school; median income, <$50 000). The primary outcome was BCPR. BCPR occurred in 3399 of 7086 OHCAs (48%). Compared with white children, BCPR was less likely in other races/ethnicities (black: adjusted odds ratio [aOR], 0.59; 95% CI, 0.52–0.68; Hispanic: aOR, 0.78; 95% CI, 0.66–0.94; and other: aOR, 0.54; 95% CI, 0.40–0.72). Compared with arrests in neighborhoods with an index score of 0, BCPR occurred less commonly for arrests with an index score of 1 (aOR, 0.80; 95% CI, 0.70–0.91), 2 (aOR, 0.75; 95% CI, 0.65–0.86), 3 (aOR, 0.52; 95% CI, 0.45–0.61), and 4 (aOR, 0.46; 95% CI, 0.36–0.59). Black children had an incrementally lower likelihood of BCPR with increasing index score while white children had an overall similar likelihood at most scores. Black children with an index of 4 were approximately half as likely to receive BCPR compared with white children with a score of 0. Conclusions: Racial and neighborhood characteristics are associated with BCPR in pediatric OHCA. Targeted CPR training for nonwhite, low-education, and low-income neighborhoods may increase BCPR and improve pediatric OHCA outcomes.
Objective-On the basis of previous evidence that polymerase delta interacting protein 2 (Poldip2) increases reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (Nox4) activity in vascular smooth muscle cells, we hypothesized that in vivo knockdown of Poldip2 would inhibit reactive oxygen species production and alter vascular function. Approach and Results-Because homozygous Poldip2 deletion is lethal, Poldip2 mice were used. Poldip2 mRNA and protein levels were reduced by ≈50% in Poldip2 aorta, with no change in p22phox, Nox1, Nox2, and Nox4 mRNAs. NADPH oxidase activity was also inhibited in Poldip2 tissue. Isolated aortas from Poldip2 mice demonstrated impaired phenylephrine and potassium chloride-induced contractions, increased stiffness, and reduced compliance associated with disruption of elastic lamellae and excessive extracellular matrix deposition. Collagen I secretion was elevated in cultured vascular smooth muscle cells from Poldip2 mice and restored by H2O2 supplementation, suggesting that this novel function of Poldip2 is mediated by reactive oxygen species. Furthermore, Poldip2 mice were protected against aortic dilatation in a model of experimental aneurysm, an effect consistent with increased collagen secretion. Conclusions-Poldip2 knockdown reduces H2O2 production in vivo, leading to increases in extracellular matrix, greater vascular stiffness, and impaired agonist-mediated contraction. Thus, unaltered expression of Poldip2 is necessary for vascular integrity and function.
Objective-Abnormalities in nitric oxide (NO) bioavailability have been reported in blacks. Whether there are differences in endothelium-derived hyperpolarizing factor (EDHF) in addition to NO between blacks and whites and how these affect physiological vasodilation remain unknown. We hypothesized that the bioavailability of vascular NO and EDHF, at rest and with pharmacological and physiological vasodilation, varies between whites and blacks. Approach and Results-In 74 white and 86 black subjects without known cardiovascular disease risk factors, forearm blood flow was measured using plethysmography at rest and during inhibition of NO with NG-monomethyl-L-arginine and of K +Ca channels (EDHF) with tetraethylammonium. The reduction in resting forearm blood flow was greater with NG-monomethyl-L- arginine (P=0.019) and similar with tetraethylammonium in whites compared with blacks. Vasodilation with bradykinin, acetylcholine, and sodium nitroprusside was lower in blacks compared with whites (all P<0.0001). Inhibition with NG-monomethyl-L-arginine was greater in whites compared with blacks with bradykinin, acetylcholine, and exercise. Inhibition with tetraethylammonium was lower in blacks with bradykinin, but greater during exercise and with acetylcholine. Conclusions-The contribution to both resting and stimulus-mediated vasodilator tone of NO is greater in whites compared with blacks. EDHF partly compensates for the reduced NO release in exercise and acetylcholine-mediated vasodilation in blacks. Preserved EDHF but reduced NO bioavailability and sensitivity characterizes the vasculature in healthy blacks.
Bradykinin (BK) stimulates tissue plasminogen activator (t-PA) release from human endothelium. Although BK stimulates both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF) release, the role of EDHF in t-PA release remains unexplored. This study sought to determine the mechanisms of BK-stimulated t-PA release in the forearm vasculature of healthy human subjects. Methods: In 33 healthy subjects (age 40.3 ± 1.9 years), forearm blood flow (FBF) and t-PA release were measured at rest and after intra-arterial infusions of BK (400 ng/min) and sodium nitroprusside (3.2 mg/min). Measurements were repeated after intra-arterial infusion of tetraethylammonium chloride (TEA; 1 μmol/min), fluconazole (0.4 μmol·min<sup>-1</sup>·l<sup>-1</sup>), and N<sup>G</sup>-monomethyl-L-arginine (L-NMMA, 8 μmol/min) to block nitric oxide, and their combination in separate studies. Results: BK significantly increased net t-PA release across the forearm (p < 0.0001). Fluconazole attenuated both BK-mediated vasodilation (-23.3 ± 2.7% FBF, p < 0.0001) and t-PA release (from 50.9 ± 9.0 to 21.3 ± 8.9 ng/min/100 ml, p = 0.02). TEA attenuated FBF (-14.7 ± 3.2%, p = 0.002) and abolished BK-stimulated t-PA release (from 22.9 ± 5.7 to -0.8 ± 3.6 ng/min/100 ml, p = 0.0002). L-NMMA attenuated FBF (p < 0.0001), but did not inhibit BK-induced t-PA release (nonsignificant). Conclusion: BK-stimulated t-PA release is partly due to cytochrome P<inf>450</inf>-derived epoxides and is inhibited by K<sup>+</sup><inf>Ca</inf> channel blockade. Thus, BK stimulates both EDHF-dependent vasodilation and t-PA release.
Background-In a previous study, we found that a biomarker risk score (BRS) comprised of C-reactive protein, fibrin-degradation products, and heat shock protein-70 predicts risk of myocardial infarction and death in coronary artery disease patients. We sought to: (1) validate the BRS in the independent BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes) cohort, (2) investigate whether 1 year of intensive medical therapy is associated with improved BRS, and (3) elucidate whether an altered BRS parallels altered risk. Methods and Results-Two thousand thirty-two subjects with coronary artery disease were followed for 5.3±1.1 years for cardiovascular events. Biomarkers were measured at baseline and retested in 1304 subjects at 1 year. BRS was determined as the biomarker number above previously defined cut-off values (C-reactive protein > 3 mg/L, heat shock protein-70 > 0.313 ng/mL, and fibrin-degradation products > 1 lg/mL). After adjustment for covariates, those with a BRS of 3 had a 4-fold increased risk of allcause death and a 6.8-fold increased risk of cardiac death compared with those with a BRS of 0 (95% CI, 2.9-16.0; P < 0.0001). All individual biomarkers decreased by 1 year, with ≈80% of patients decreasing their BRS. BRS recalibrated at 1 year also predicted risk. Those with 1-year BRS of 2 to 3 had a 4-year mortality rate of 21.1% versus 7.4% for those with BRS of 0 to 1 (P < 0.0001). Conclusions-Our results validate the ability of the BRS to identify coronary artery disease patients at very high near-term risk of myocardial infarction/death. After 1 year of intensive medical therapy, the BRS decreased significantly, and the reclassified BRS continued to track with risk. Our results suggest that repeated BRS measurements might be used to assess risk and recalibrate therapy.
Murine gammaherpesvirus 68 (γHV68) infection of mice provides a tractable small-animal model system for assessing the requirements for the establishment and maintenance of gammaherpesvirus latency within the lymphoid compartment. The M2 gene product of γHV68 is a latency-associated antigen with no discernible homology to any known proteins. Here we focus on the requirement for the M2 gene in splenic B-cell latency. Our analyses showed the following. (i) Low-dose (100 PFU) inoculation administered via the intranasal route resulted in a failure to establish splenic B-cell latency at day 16 postinfection. (ii) Increasing the inoculation dose to 4 × 10 5 PFU administered via the intranasal route partially restored the establishment of B-cell latency at day 16, but no virus reactivation was detected upon explant into tissue cultures. (iii) Although previous data failed to detect a phenotype of the M2 mutant upon high-dose intraperitoneal inoculation, decreasing the inoculation dose to 100 PFU administered intraperitoneally revealed a splenic B-cell latency phenotype at day 16 that was very similar to the phenotype observed upon high-dose intranasal inoculation. (iv) After low-dose intraperitoneal inoculation, fractionated B-cell populations showed that the M2 mutant virus was able to establish latency in surface immunoglobulin B-negative (sIgD - ) B cells; by 6 months postinfection, equivalent frequencies of M2 mutant and marker rescue viral genome-positive sIgD - B cells were detected. (v) Like the marker rescue virus, the M2 mutant virus also established latency in splenic naive B cells upon low-dose intraperitoneal inoculation, but there was a significant lag in the decay of this latently infected reservoir compared to that seen with the marker rescue virus. (vi) After low-dose intranasal inoculation, by day 42 postinfection, latency was observed in the spleen, although at a frequency significantly lower than that in the marker rescue virus-infected mice; by 3 months postinfection, nearly equivalent levels of viral genome-positive cells were observed in the spleens of marker rescue virus- and M2 mutant virus-infected mice, and these cells were exclusively sIgD - B cells. Taken together, these data convincingly demonstrate a role for the M2 gene product in reactivation from splenic B cells and also suggest that disruption of the M2 gene leads to dose- and route-specific defects in the efficient establishment of splenic B-cell latency.
by
Daniel E. Forman;
Michael W. Rich;
Karen P. Alexander;
Susan Zieman;
Mathew S. Maurer;
Samer S. Najjar;
Joseph C. Cleveland;
Harlan M. Krumholz;
Nanette Wenger
by
Douglas I. Walker;
Kurt D. Pennell;
Karan Uppal;
Xiaoyan Xia;
Philip K. Hopke;
Mark J. Utell;
Richard P. Phipps;
Patricia J. Sime;
Patricia Rohrbeck;
Timothy M. Mallon;
Dean P Jones
A pilot study was conducted to test the feasibility of using Department of Defense Serum Repository (DoDSR) samples to study health and exposure-related effects. Methods: Thirty unidentified human serum samples were obtained from the DoDSR and analyzed for normal serum metabolites with high-resolution mass spectrometry and serum levels of free benzo(a)pyrene (BaP) by gas chromatography-mass spectrometry. Metabolic associations with BaP were determined using a metabolome-wide association study (MWAS) and metabolic pathway enrichment. Results: The serum analysis detected normal ranges of glucose, selected amino acids, fatty acids, and creatinine. Free BaP was detected in a broad concentration range. MWAS of BaP showed associations with lipids, fatty acids, and sulfur amino acid metabolic pathways. Conclusion: The results show that the DoDSR samples are of sufficient quality for chemical profiling of DoD personnel.
Direct conversion or reprogramming of human postnatal cells into endothelial cells (ECs), bypassing stem or progenitor cell status, is crucial for regenerative medicine, cell therapy, and pathophysiological investigation but has remained largely unexplored. Objective: We sought to directly reprogram human postnatal dermal fibroblasts to ECs with vasculogenic and endothelial transcription factors and determine their vascularizing and therapeutic potential. Methods and Results: We utilized various combinations of 7 EC transcription factors to transduce human postnatal dermal fibroblasts and found that ER71/ETV2 (ETS variant 2) alone best induced endothelial features. KDR + (kinase insert domain receptor) cells sorted at day 7 from ER71/ETV2-transduced human postnatal dermal fibroblasts showed less mature but enriched endothelial characteristics and thus were referred to as early reprogrammed ECs (rECs), and did not undergo maturation by further culture. After a period of several weeks' transgene-free culture followed by transient reinduction of ER71/ETV2, early rECs matured during 3 months of culture and showed reduced ETV2 expression, reaching a mature phenotype similar to postnatal human ECs. These were termed late rECs. While early rECs exhibited an immature phenotype, their implantation into ischemic hindlimbs induced enhanced recovery from ischemia. These 2 rECs showed clear capacity for contributing to new vessel formation through direct vascular incorporation in vivo. Paracrine or proangiogenic effects of implanted early rECs played a significant role in repairing hindlimb ischemia. Conclusions: This study for the first time demonstrates that ER71/ETV2 alone can directly reprogram human postnatal cells to functional, mature ECs after an intervening transgene-free period. These rECs could be valuable for cell therapy, personalized disease investigation, and exploration of the reprogramming process.