Citations

Background: High sensitivity C-reactive protein is a risk factor atherosclerosis and plaque rupture. We aimed to determine the role of high-sensitivity C reactive protein in predicting future cerebrovascular events (CVA), including stroke and transient ischemic attack, in patients undergoing routine carotid endarterectomy (CEA). Methods: A total of 251 patients underwent routine CEA without any history of stroke. At baseline prior to CEA, patients underwent routine laboratory testing, including testing for novel biomarkers including hs-CRP. Patients were followed for a median of 10.9 years (IQR 7.3, 13.4) for the development of CVA with regular nursing follow-up and/or chart review. Results: Of 251 patients enrolled in the study, 19 patients without prior CVA subsequently developed CVA during follow-up. In univariate analysis, baseline hsCRP was significantly higher in patients who developed CVA during follow-up vs. those that did not (8.1 (IQR 2.2, 46.3) mg/L vs. 3.85(0.9, 11.75) mg/L; p=0.0054)(Figure 1). After adjusting for confounders including age. diabetes mellitus, cholesterol, systolic blood pressure, history of smoking, aspirin use and duration of follow-up, log hsCRP was an independent predictor of CVA during follow-up after CEA (L-R 9.9; p=0.0016). Discussion: Hs-CRP appears to be a risk factor for CVA during follow-up after CEA. Further investigation is necessary to determine the role of risk modification in these patients and the therapeutic potential of reducing inflammation in this population.

AbstractAimsPatients with renovascular hypertension (RVH) exhibit elevated urinary mtDNA copy numbers, considered to constitute surrogate markers of renal mitochondrial injury. The modest success of percutaneous transluminal renal angioplasty (PTRA) in restoring renal function in RVH has been postulated to be partly attributable to acute reperfusion injury. We hypothesized that mitoprotection during revascularization would ameliorate PTRA–induced renal mitochondrial injury, reflected in elevated urinary mtDNA copy numbers and improve blood pressure and functional outcomes 3 months later.MethodsWe prospectively measured urinary copy number of the mtDNA genes COX3 and ND1 using qPCR in RVH patients before and 24 hrs after PTRA, performed during IV infusion of vehicle (n = 8) or the mitoprotective drug elamipretide (ELAM, 0.05 mg/kg/h, n = 6). Five healthy volunteers (HV) served as controls. Urinary mtDNA levels were also assessed in RVH and normal pigs (n = 7 each), in which renal mitochondrial structure and density were studied ex‐vivo.ResultsBaseline urinary mtDNA levels were elevated in all RVH patients vs HV and directly correlated with serum creatinine levels. An increase in urinary mtDNA 24 hours after PTRA was blunted in PTRA+ELAM vs PTRA+Placebo. Furthermore, 3‐months after PTRA, systolic blood pressure decreased and estimated glomerular filtration rate increased only in ELAM–treated subjects. In RVH pigs, mitochondrial damage was observed using electron microscopy in tubular cells and elevated urinary mtDNA levels correlated inversely with renal mitochondrial density.ConclusionsPTRA leads to an acute rise in urinary mtDNA, reflecting renal mitochondrial injury that in turn inhibits renal recovery. Mitoprotection might minimize PTRA–associated mitochondrial injury and improve renal outcomes after revascularization.

Objective— Coronary endothelial dysfunction (ED) is an early stage of atherosclerosis and is associated with impaired high-density lipoprotein (HDL) function. A functional polymorphism at the haptoglobin (Hp) gene locus (rs72294371) has been associated with marked differences in HDL structure and function. We sought to determine whether Hp phenotype was associated with coronary ED and whether the amount of hemoglobin (Hb) tethered to HDL via Hp was Hp-type dependent and associated with ED. Approach and Results— Microvascular and epicardial coronary endothelial function was assessed in 338 individuals with nonobstructive coronary artery disease. Microvascular ED was defined as <50% change in coronary blood flow and epicardial ED as ≥20% decrease in coronary artery diameter after intracoronary acetylcholine infusion. The amount of Hb bound to HDL was measured by ELISA after HDL purification from plasma samples using immune-affinity chromatography. One hundred and seventy of the individuals in this study (50.3%) were diagnosed with microvascular ED, 143 (42.3%) with epicardial ED, and 67 (19.7%) had diabetes mellitus (DM). Hp phenotype was significantly associated with microvascular ( P =0.01) and epicardial ED ( P =0.04) among DM individuals. There was a significant and inverse correlation between the amount of HDL-bound Hb and change in coronary blood flow (r=−0.40; P <0.0001) and in coronary artery diameter (r=−0.44; P <0.0001) in response to acetylcholine infusion. Hb content of HDL was significantly increased in individuals with Hp 2-2 and DM. In a logistic regression model, Hp 2-2 phenotype was associated with microvascular ED (odds ratio, 1.9; P =0.03) and the amount of HDL-bound Hb was an independent predictor of both microvascular (odds ratio, 4.6 for each 1-SD increase; P <0.0001) and epicardial (odds ratio, 2.2; P <0.0001) ED. Conclusions— Hp phenotype is significantly associated with coronary ED in DM individuals. This association is likely related to increased Hb tethering to HDL via Hp 2-2 in DM.

Aim Angina pectoris in the absence of obstructive coronary artery disease (CAD) is common and is associated with poor quality of life (QOL). Coronary microvascular endothelial dysfunction is associated with myocardial ischaemia and is a common cause of angina. We hypothesise that evaluation of coronary endothelial function, its diagnosis and treatment will favourably impact QOL in patients with angina symptoms and non-obstructive CAD. Methods and results Follow-up was done on 457 patients with chest pain and non-obstructive coronary arteries who had undergone coronary vascular reactivity evaluation by administration of intracoronary acetylcholine at the time of diagnostic study. After a mean follow-up of 8.4±4.7 years, QOL was assessed by administration of the SF-36 QOL survey. Patients diagnosed and treated for microvascular endothelial dysfunction had a higher (better) overall mental composite score (44.8 vs 40.9, p=0.036) and mental health score (44.2 vs 40.7, p=0.047), and a trend towards higher vitality scores (39.1 vs 35.9, p=0.053) and role emotional scores (43.6 vs 40.4, p=0.073), compared with patients with normal endothelial function. Conclusion Among patients with chest pain and normal coronaries, diagnosis and treatment of coronary microvascular endothelial dysfunction in those with angina pectoris and non-obstructive CAD are associated with better QOL compared with patients with normal endothelial function.

Abstract Mesenchymal stem/stromal cells (MSCs) release extracellular vesicles (EVs), which shuttle proteins to recipient cells, promoting cellular repair. We hypothesized that cardiovascular risk factors may alter the pattern of proteins packed within MSC-derived EVs. To test this, we compared the protein cargo of EVs to their parent MSCs in pigs with metabolic syndrome (MetS) and Lean controls. Porcine MSCs were harvested from abdominal fat after 16 weeks of Lean- or MetS-diet (n = 5 each), and their EVs isolated. Following liquid chromatography mass spectrometry proteomic analysis, proteins were classified based on cellular component, molecular function, and protein class. Five candidate proteins were validated by Western blot. Clustering analysis was performed to identify primary functional categories of proteins enriched in or excluded from EVs. Proteomics analysis identified 6,690 and 6,790 distinct proteins in Lean- and MetS-EVs, respectively. Differential expression analysis revealed that 146 proteins were upregulated and 273 downregulated in Lean-EVs versus Lean-MSCs, whereas 787 proteins were upregulated and 185 downregulated in MetS-EVs versus MetS-MSCs. Proteins enriched in both Lean- and MetS-EVs participate in vesicle-mediated transport and cell-to-cell communication. Proteins enriched exclusively in Lean-EVs modulate pathways related to the MSC reparative capacity, including cell proliferation, differentiation, and activation, as well as transforming growth factor-β signaling. Contrarily, proteins enriched only in MetS-EVs are linked to proinflammatory pathways, including acute inflammatory response, leukocyte transendothelial migration, and cytokine production. Coculture with MetS-EVs increased renal tubular cell inflammation. MetS alters the protein cargo of porcine MSC-derived EVs, selectively packaging specific proinflammatory signatures that may impair their ability to repair damaged tissues. Stem Cells Translational Medicine 2019;8:430–440

Abstract Mental and physical stress is thought to play an important causative factor in apical ballooning syndrome (ABS) likely secondary to the vasomotor dysfunction. However, there are currently few data related to the impact of physical stress in this unique cardiomyopathy. A total 18 patients, including 8 females with history of ABS and 10 post-menopausal controls, underwent physical and mental tests. Assessments included the pain-induced peripheral artery tonometry scores (PIPATs) and mental stress peripheral artery tonometry scores (PATs). Compared with control group, PIPATs were significantly attenuated in patients with ABS in both baseline and post-mental stress (0.94 ± 0.08 vs1.30 ± 0.54, P <.05 and 0.87 ± 0.19 vs1.24 ± 0.21 P = .01, respectively); mental stress PATs were significantly lower in patients with ABS, both in Stroop test (0.79 ± 0.30 vs 1.24 ± 0.43, P = .01) and arithmetic test (0.91 ± 0.27 vs 1.36 ± 0.57, P = .01). PIPATs correlated significantly with mental stress PATs, both in arithmetic and Stroop test (P <.05). The PIPATs were attenuated in female with history of ABS and the vascular response to pain may provide a different pathogenesis mechanism on detecting patients with ABS.

Background: Fifty percent of patients with autosomal dominant polycystic kidney disease (ADPKD) present hypertension (HTN) early on, which increases to nearly 100% at end-stage, and is associated with faster renal functional decline. Endothelial dysfunction (ED) accompanied by oxidative stress (OS) precedes the development of HTN, but the mechanisms responsible remain unknown. The aim of this study was to determine whether NADPH oxidase (NOX4) and mitochondrial dysfunction contribute to OS and ED preceding HTN in early ADPKD. Methods: We prospectively measured plasma levels of homocysteine (Hcy), 8-isoprostane, NOX4 and the mtDNA genes COX3 and ND1 in young normotensive (without BP medication) ADPKD patients, and age-matched healthy volunteers (HV) (n=10, each). Total kidney volume (TKV) and Renal Blood Flow (RBF) were evaluated by MRI. Results: BP levels were higher in ADPKD, and HtTKV was twofold higher in ADPKD vs. controls. eGFR and RBF were similar between the groups (Table). Plasma Hcy, 8-isoprostanes and NOX4 were higher in ADPKD, and correlated directly with HtTKV (p<0.05, Figure), but the correlation with RBF was not significant. Plasma mtDNA copy number were lower in ADPKD compared to controls, and correlated inversely with HtTKV(R 2 0.397 and 0.392 respectively). Conclusion: Early ADPKD is associated with elevation in Hcy, 8-isoprostane, and NOX4 levels, and decreased mtDNA copy numbers, which precede the reduction in RBF and the development of HTN, and are associated with disease severity. NOX4 and mitochondrial abnormalities may contribute to oxidative stress, endothelial dysfunction, and possibly the development of HTN and disease progression in ADPKD.

Background: We have previously shown in patients with renovascular hypertension (RVH) that elevated urinary mtDNA copy numbers represent surrogate markers of renal mitochondrial injury. Revascularization with percutaneous transluminal renal angioplasty (PTRA) can lead to acute renal reperfusion injury. However, whether PTRA induces renal mitochondrial injury remains unknown. Methods: We prospectively measured urinary copy number of the mtDNA genes cytochrome-c oxidase-3 (COX3) and NADH dehydrogenase subunit-1 (ND1) by qPCR in 5 RVH patients before and 24hrs after PTRA. Five additional patients were treated before and during PTRA with the mitoprotective drug elamipretide (ELAM, 0.05 mg/kg/hr IV infusion). Healthy volunteers (HV) served as controls (n=5). Results: Baseline blood pressure was similarly elevated in both RVH groups, and eGFR lower than HV (Table). Baseline urinary COX3 and ND1 levels were similarly higher in both RVH groups compared with HV (Fig. A), and directly correlated with serum creatinine levels (R 2 =0.74, p=0.001 and R 2 =0.45, p=0.033, respectively). Over 3 months, eGFR increased only in ELAM-treated patients (Fig. B). Furthermore, the rise in urinary mtDNA 24hrs after PTRA was blunted in PTRA+ELAM versus PTRA+Placebo, and inversely correlated with the change in eGFR of 3 months after PTRA (Fig. C). Conclusion: PTRA induces an acute rise in urinary mtDNA levels, likely reflecting renal mitochondrial injury due to reperfusion injury that inhibits renal recovery. Mitoprotection in this cohort limited PTRA-associated mitochondrial injury and improved renal outcomes after revascularization.

Hypertension, an important cause of chronic kidney disease, is characterized by peritubular capillary (PTC) loss. Circulating levels of endothelial microparticles (EMPs) reflect systemic endothelial injury. We hypothesized that systemic and urinary PTC-EMPs levels would reflect renal microvascular injury in hypertensive patients. We prospectively measured by flow cytometry renal vein, inferior vena cava, and urinary levels of EMPs in essential (n=14) and renovascular (RVH; n=24) hypertensive patients and compared them with peripheral blood and urinary levels in healthy volunteers (n=14). PTC-EMPs were identified as urinary exosomes positive for the PTC marker plasmalemmal-vesicle–associated protein. In 7 RVH patients, PTC and fibrosis were also quantified in renal biopsy, and in 18 RVH patients, PTC-EMPs were measured again 3 months after continued medical therapy with or without stenting (n=9 each). Renal vein and systemic PTC-EMPs levels were not different among the groups, whereas their urinary levels were elevated in both RVH and essential hypertension versus healthy volunteers (56.8%±12.7% and 62.8%±10.7% versus 34.0%±17.8%; both P ≤0.001). Urinary PTC-EMPs levels correlated directly with blood pressure and inversely with estimated glomerular filtration rate. Furthermore, in RVH, urinary PTC-EMPs levels correlated directly with stenotic kidney hypoxia, histological PTC count, and fibrosis and inversely with cortical perfusion. Three months after treatment, the change in urinary PTC-EMPs levels correlated inversely with a change in renal function ( r =−0.582; P =0.011). Therefore, urinary PTC-EMPs levels are increased in hypertensive patients and may reflect renal microcirculation injury, whereas systemic PTC-EMPs levels are unchanged. Urinary PTC-EMPs may be useful as novel biomarkers of intrarenal capillary loss.