Citations

Background: Left ventricular global longitudinal strain (GLS) is associated with long-term outcomes of patients with severe aortic stenosis. However, its prognostic value in patients with moderate aortic stenosis remains unknown. Methods: Patients diagnosed with moderate aortic stenosis (1.0< aortic valve area ≤1.5 cm 2 ) and left ventricular ejection fraction ≥50% were identified. GLS was assessed by 2-dimensional strain imaging using speckle-tracking method. All-cause mortality was assessed according to the median GLS value. Results: Two hundred eighty-seven patients were included (median age 76 years; 47% male). Mean aortic valve area was 1.25 cm 2 , left ventricular ejection fraction 62%, and median GLS −15.2%. During a median follow-up of 3.9 years, there were 103 deaths (36%). Mortality was higher in patients with GLS>−15.2% (hazard ratio 2.62 [95% CI 1.69–4.06]) compared with patients with GLS ≤−15.2% even after adjusting for confounders. Mortality rates at 1, 3, 5 years were 21%, 35%, 48%, respectively, in patients with GLS >−15.2%, and 6%, 15%, 19% in those with GLS ≤−15.2%. Even among those with left ventricular ejection fraction ≥60%, GLS discriminated higher-risk patients ( P =0.0003). During follow-up, 106 (37%) patients underwent aortic valve replacement with median waiting-time of 2.4 years, and their survival was better than patients without aortic valve replacement. Among those patients undergoing aortic valve replacement, prognosis was still worse in patients with GLS >−15.2% ( P =0.04). Mortality rates at 1, 3, 5 years were 2%, 10%, 20%, respectively, in patients with GLS >-15.2% and 2%, 5%, 6% in those with GLS ≤−15.2%. Conclusions: Impaired GLS in moderate aortic stenosis patients is associated with higher mortality rates even among those undergoing aortic valve replacement.

Endothelial progenitor cells (EPCs) patrols the circulation and contributes to endothelial cell regeneration. Atherosclerotic renal artery stenosis (ARAS) induces microvascular loss in the stenotic kidney (STK). Low-energy shockwave therapy (SW) can induce angiogenesis and restore the STK microcirculation, but the underlying mechanism remains unclear. We tested the hypothesis that SW increases EPC homing to the swine STK, associated with capillary regeneration. Normal pigs and pigs after 3 wk of renal artery stenosis were treated with six sessions of low-energy SW (biweekly for three consecutive weeks) or left untreated. Four weeks after completion of treatment, we assessed EPC (CD34+/KDR+) numbers and levels of the homing-factor stromal cell-derived factor (SDF)-1 in the inferior vena cava and the STK vein and artery, as well as urinary levels of vascular endothelial growth factor (VEGF) and integrin-1β. Subsequently, we assessed STK morphology, capillary count, and expression of the proangiogenic growth factors angiopoietin-1, VEGF, and endothelial nitric oxide synthase ex vivo. A 3-wk low-energy SW regimen improved STK structure, capillary count, and function in ARAS+SW, and EPC numbers and gradients across the STK decreased. Plasma SDF-1 and renal expression of angiogenic factors were increased in ARAS+SW, and urinary levels of VEGF and integrin-1β tended to rise during the SW regimen. In conclusion, SW improves ischemic kidney capillary density, which is associated with, and may be at least in part mediated by, promoting EPCs mobilization and homing to the stenotic kidney.

Cellular senescence, a permanent arrest of cell proliferation, is characterized by a senescence-associated secretory phenotype (SASP), which reinforces senescence and exerts noxious effects on adjacent cells. Recent studies have suggested that transplanting small numbers of senescent cells suffices to provoke tissue inflammation. We hypothesized that senescent cells can directly augment renal injury. Primary scattered tubular-like cells (STCs) acquired from pig kidneys were irradiated by 10 Gy of cesium radiation, and 3 wk later cells were characterized for levels of senescence and SASP markers. Control or senescent STCs were then prelabeled and injected (5 × 105 cells) into the aorta of C57BL/6J mice. Four weeks later, renal oxygenation was studied in vivo using 16.4-T magnetic resonance imaging and function by plasma creatinine level. Renal markers of SASP, fibrosis, and microvascular density were evaluated ex vivo. Per flow cytometry, irradiation induced senescence in 80–99% of STCs, which showed increased gene expression of senescence and SASP markers, senescence-associated β-galactosidase staining, and cytokine levels (especially IL-6) secreted in conditioned medium. Four weeks after injection, cells were detected engrafted in the mouse kidneys with no evidence for rejection. Plasma creatinine and renal tissue hypoxia increased in senescent compared with control cells. Senescent kidneys were more fibrotic, with fewer CD31+ endothelial cells, and showed upregulation of IL-6 gene expression. Therefore, exogenously delivered senescent renal STCs directly injure healthy mouse kidneys. Additional studies are needed to determine the role of endogenous cellular senescence in the pathogenesis of kidney injury and evaluate the utility of senolytic therapy.

Metabolic syndrome (MetS) profoundly changes the contents of mesenchymal stem cells and mesenchymal stem cells–derived extracellular vesicles (EVs). The anti-inflammatory TGF-β (transforming growth factor-β) is selectively enriched in EVs from Lean but not from MetS pigs, but the functional impact of this endowment remains unknown. We hypothesized that Lean-EVs more effectively induce regulatory T cells in injured kidneys. Five groups of pigs (n=7 each) were studied after 16 weeks of diet-induced MetS and unilateral renal artery stenosis (RAS; MetS+RAS). Two groups of MetS+RAS were treated 4 weeks earlier with an intrarenal injection of either Lean-EVs or MetS-EVs. MetS+RAS had lower renal volume, renal blood flow, and glomerular filtration rate than MetS pigs. Compared with Lean-EVs, MetS-EVs were less effective in improving renal function and decreasing tubular injury and fibrosis in MetS+RAS. Lean-EVs upregulated TGF-β expression in stenotic kidney and increased regulatory T cells numbers more prominently. Furthermore, markedly upregulated anti-inflammatory M2 macrophages reduced proinflammatory M1 macrophages, and CD8 + T cells were detected in stenotic kidneys treated with Lean-EVs compared with MetS-EVs, and renal vein levels of interleukin-1β were reduced. In vitro, coculture of Lean-EVs with activated T cells led to greater TGF-β-dependent regulatory T cells induction than did MetS-EVs. Therefore, the beneficial effects of mesenchymal stem cells–derived EVs on injured kidneys might be partly mediated by their content of TGF-β signaling components, which permitting increased Treg preponderance. Modulating EV cargo and transforming their functionality might be useful for renal repair.

INTRODUCTION The cerebral cortex underlies our complex cognitive capabilities. Variations in human cortical surface area and thickness are associated with neurological, psychological, and behavioral traits and can be measured in vivo by magnetic resonance imaging (MRI). Studies in model organisms have identified genes that influence cortical structure, but little is known about common genetic variants that affect human cortical structure. RATIONALE To identify genetic variants associated with human cortical structure at both global and regional levels, we conducted a genome-wide association meta-analysis of brain MRI data from 51,665 individuals across 60 cohorts. We analyzed the surface area and average thickness of the whole cortex and 34 cortical regions with known functional specializations. RESULTS We identified 369 nominally genome-wide significant loci ( P < 5 × 10 −8 ) associated with cortical structure in a discovery sample of 33,992 participants of European ancestry. Of the 360 loci for which replication data were available, 241 loci influencing surface area and 66 influencing thickness remained significant after replication, with 237 loci passing multiple testing correction ( P < 8.3 × 10 −10 ; 187 influencing surface area and 50 influencing thickness). Common genetic variants explained 34% (SE = 3%) of the variation in total surface area and 26% (SE = 2%) in average thickness; surface area and thickness showed a negative genetic correlation ( r G = −0.32, SE = 0.05, P = 6.5 × 10 −12 ), which suggests that genetic influences have opposing effects on surface area and thickness. Bioinformatic analyses showed that total surface area is influenced by genetic variants that alter gene regulatory activity in neural progenitor cells during fetal development. By contrast, average thickness is influenced by active regulatory elements in adult brain samples, which may reflect processes that occur after mid-fetal development, such as myelination, branching, or pruning. When considered together, these results support the radial unit hypothesis that different developmental mechanisms promote surface area expansion and increases in thickness. To identify specific genetic influences on individual cortical regions, we controlled for global measures (total surface area or average thickness) in the regional analyses. After multiple testing correction, we identified 175 loci that influence regional surface area and 46 that influence regional thickness. Loci that affect regional surface area cluster near genes involved in the Wnt signaling pathway, which is known to influence areal identity. We observed significant positive genetic correlations and evidence of bidirectional causation of total surface area with both general cognitive functioning and educational attainment. We found additional positive genetic correlations between total surface area and Parkinson’s disease but did not find evidence of causation. Negative genetic correlations were evident between total surface area and insomnia, attention deficit hyperactivity disorder, depressive symptoms, major depressive disorder, and neuroticism. CONCLUSION This large-scale collaborative work enhances our understanding of the genetic architecture of the human cerebral cortex and its regional patterning. The highly polygenic architecture of the cortex suggests that distinct genes are involved in the development of specific cortical areas. Moreover, we find evidence that brain structure is a key phenotype along the causal pathway that leads from genetic variation to differences in general cognitive function. Identifying genetic influences on human cortical structure. ( A ) Measurement of cortical surface area and thickness from MRI. ( B ) Genomic locations of common genetic variants that influence global and regional cortical structure. ( C ) Our results support the radial unit hypothesis that the expansion of cortical surface area is driven by proliferating neural progenitor cells. ( D ) Cortical surface area shows genetic correlation with psychiatric and cognitive traits. Error bars indicate SE. IMAGE CREDITS: (A) K. COURTNEY; (C) M. R. GLASS

Background: Heart rate variability (HRV) and pulse rate variability are indices of autonomic cardiac modulation. Increased pericardial fat is associated with worse cardiovascular outcomes. We hypothesized that progressive increases in pericardial fat volume and inflammation prospectively dampen HRV in hypercholesterolemic pigs. Methods: WT (wild type) or PCSK9 (proprotein convertase subtilisin-like/kexin type-9) gain-of-function Ossabaw mini-pigs were studied in vivo before and after 3 and 6 months of a normal diet (WT-normal diet, n=4; PCSK9-normal diet, n=6) or high-fat diet (HFD; WT-HFD, n=3; PCSK9-HFD, n=6). The arterial pulse waveform was obtained from an arterial telemetry transmitter to analyze HRV indices, including SD (SD of all pulse-to-pulse intervals over a single 5-minute period), root mean square of successive differences, proportion >50 ms of normal-to-normal R-R intervals, and the calculated ratio of low-to-high frequency distributions (low-frequency power/high-frequency power). Pericardial fat volumes were evaluated using multidetector computed tomography and its inflammation by gene expression of TNF (tumor necrosis factor)-α. Plasma lipid panel and norepinephrine level were also measured. Results: At diet completion, hypercholesterolemic PCSK9-HFD had significantly ( P <0.05 versus baseline) depressed HRV (SD of all pulse-to-pulse intervals over a single 5-minute period, root mean square of successive differences, proportion >50 ms, high-frequency power, low-frequency power), and both HFD groups had higher sympathovagal balance (SD of all pulse-to-pulse intervals over a single 5-minute period/root mean square of successive differences, low-frequency power/high-frequency power) compared with normal diet. Pericardial fat volumes and LDL (low-density lipoprotein) cholesterol concentrations correlated inversely with HRV and directly with sympathovagal balance, while sympathovagal balance correlated directly with plasma norepinephrine. Pericardial fat TNF-α expression was upregulated in PCSK9-HFD, colocalized with nerve fibers, and correlated inversely with root mean square of successive differences and proportion >50 ms. Conclusions: Progressive pericardial fat expansion and inflammation are associated with a fall in HRV in Ossabaw mini-pigs, implying aggravated autonomic imbalance. Hence, pericardial fat accumulation is associated with alterations in HRV and the autonomic nervous system. Visual Overview: A visual overview is available for this article.

Objectives The primary objective was to examine the association between hyperlipidaemia (HLP) and 5-year survival after incident acute myocardial infarction (AMI). The secondary objectives were to assess the effect of HLP on survival to discharge across patient subgroups, and the impact of statin prescription, intensity and long-term statin adherence on 5-year survival. Methods Retrospective cohort study of 7071 patients hospitalised for AMI at Mayo Clinic from 2001 through 2011. Of these, 2091 patients with HLP (age (mean±SD) 69.7±13.5) were propensity score matched to 2091 patients without HLP (age 70.6±14.2). Results In matched patients, HLP was associated with higher rate of survival to discharge than no HLP (95% vs 91%; log-rank <0.0001). At year 5, the adjusted HR for all-cause mortality in patients with HLP versus no HLP was 0.66 (95% CI 0.58–0.74), and patients with prescription statin versus no statin was 0.24 (95% CI 0.21 to 0.28). The mean survival was 0.35 year greater in patients with HLP than in those with no HLP (95% CI 0.25 to 0.46). Patients with HLP gained on an average 0.17 life year and those treated with statin 0.67 life year at 5 years after AMI. The benefit of concurrent HLP was consistent across study subgroups. Conclusions In patients with AMI, concomitant HLP was associated with increased survival and a net gain in life years, independent of survival benefit from statin therapy. The results also reaffirm the role of statin prescription, intensity and adherence in reducing the mortality after incident AMI.

Abstract BACKGROUND Mitochondria modulate endothelial cell (EC) function, but may be damaged during renal disease. We hypothesized that the ischemic and metabolic constituents of swine renovascular disease (RVD) induce mitochondrial damage and impair the function of renal artery ECs. METHODS Pigs were studied after 16 weeks of metabolic syndrome (MetS), renal artery stenosis (RAS), or MetS + RAS, and Lean pigs served as control (n = 6 each). Mitochondrial morphology, homeostasis, and function were measured in isolated primary stenotic-kidney artery ECs. EC functions were assessed in vitro, whereas vasoreactivity of renal artery segments was characterized in organ baths. RESULTS Lean + RAS and MetS + RAS ECs showed increased mitochondrial area and decreased matrix density. Mitochondrial biogenesis was impaired in MetS and MetS + RAS compared with their respective controls. Mitochondrial membrane potential similarly decreased in MetS, Lean + RAS, and MetS + RAS groups, whereas production of reactive oxygen species increased in MetS vs. Lean, but further increased in both RAS groups. EC tube formation was impaired in MetS, RAS, and MetS + RAS vs. Lean, but EC proliferation and endothelial-dependent relaxation of renal artery segments were blunted in MetS vs. Lean, but further attenuated in Lean + RAS and MetS + RAS. CONCLUSIONS MetS and RAS damage mitochondria in pig renal artery ECs, which may impair EC function. Coexisting MetS and RAS did not aggravate EC mitochondrial damage in the short time of our in vivo studies, suggesting that mitochondrial injury is associated with impaired renal artery EC function.

TPS7569 Background: Progress in genome technology allows analysis of previously completed trials to identify patients subgroups potentially benefiting from therapy. Enzastaurin is a potent inhibitor of protein kinase C beta (PKC- b) and suppresses the phosphoinositide 3-kinase (PI3K)/AKT pathway. The safety and efficacy of Enzastaurin has been tested in more than 60 clinical trials including 2 major studies in DLBCL: (1) PRELUDE (A phase III maintenance trial of Enzastaurin vs Placebo, N=758) ( Crump, 2016), and (2) S028 (A randomized phase II study of Enzastaurin/R-CHOP vs R-CHOP in frontline intermediate/high-risk DLBCL, N=101) ( Hainsworth, 2016). DNA samples extracted from blood of patients from PRELUDE were retrospectively genotyped using whole genome SNP arrays. From the genome wide screening a novel genetic biomarker, DGM1, was identified showing high correlation with response to Enzastaurin treatment ( Luo, ASH 2018). Importantly, these findings were replicated in the phase II S028 study. In the S028 study the hazard ratio (HR) for OS in high-risk (IPI ≥ 3) DGM1 positive (+) patients who received Enzastaurin/R-CHOP was 0.28 (0.1-0.81) when compared to subjects who received R-CHOP, a benefit favoring Enzastaurin (p=0.018). These data suggest that addition of Enzastaurin to R-CHOP may significantly improve outcome in frontline high-risk DGM1 (+) DLBCL. The ENGINE study was initiated to validate this finding in a prospective study. Methods: Adult patients must have untreated CD20+ DLBCL, IPI ≥ 3. Patients are randomized 1:1 to Enzastaurin/R-CHOP or Placebo/R-CHOP for 6 cycles during combination phase. Each subject’s treatment assignment will be unblinded after response assessment at the end of the combination phase. Subjects randomized to the investigational arm who have a complete or partial response will have the option to continue in the single agent phase to receive Enzastaurin for up to 2 additional years. The study intends to enroll approximately 235 patients with primary endpoint of OS in DGM1 (+) patients. The study is ongoing with 51 sites open in the US and China. As of 22 Jan 2019, 70 patients have been randomized. Clinical trial information: NCT03263026.