Red Blood Cell Dysfunction Induced by High-Fat Diet: Potential Implications for Obesity-Related Atherosclerosis.

BACKGROUND: High-fat diet (HFD) promotes endothelial dysfunction and proinflammatory monocyte activation, which contribute to atherosclerosis in obesity. We investigated whether HFD also induces the dysfunction of red blood cells (RBCs), which serve as a reservoir for chemokines via binding to Duffy antigen receptor for chemokines (DARC). METHODS AND RESULTS: A 60% HFD for 12 weeks, which produced only minor changes in lipid profile in C57/BL6 mice, markedly augmented the levels of monocyte chemoattractant protein-1 bound to RBCs, which in turn stimulated macrophage migration through an endothelial monolayer. Levels of RBC-bound KC were also increased by HFD. These effects of HFD were abolished in DARC(-/-) mice. In RBCs from HFD-fed wild-type and DARC(-/-) mice, levels of membrane cholesterol and phosphatidylserine externalization were increased, fostering RBC-macrophage inflammatory interactions and promoting macrophage phagocytosis in vitro. When labeled ex vivo and injected into wild-type mice, RBCs from HFD-fed mice exhibited ≈3-fold increase in splenic uptake. Finally, RBCs from HFD-fed mice induced increased macrophage adhesion to the endothelium when they were incubated with isolated aortic segments, indicating endothelial activation. CONCLUSIONS: RBC dysfunction, analogous to endothelial dysfunction, occurs early during diet-induced obesity and may serve as a mediator of atherosclerosis. These findings may have implications for the pathogenesis of atherosclerosis in obesity, a worldwide epidemic.

Placental lactogen is expressed but is not translated into protein in breast cancer.

INTRODUCTION: Several studies reported that the pregnancy-specific hormone placental lactogen (hPL) is expressed at both mRNA and protein levels in breast cancer. The overall objective was to establish hPL, the product of the CSH1 and CSH2 genes, as a biomarker for breast cancer. METHODS: CSH expression was determined at the mRNA level in breast cancer cell lines (BCC) and primary carcinomas by real-time and conventional PCR and the products verified as CSH1 by sequencing. Expression of hPL protein was examined by western blots and immuno-histochemistry, using commercial and custom-made polyclonal and monoclonal antibodies. RESULTS: Variable levels of CSH mRNA were detected in several BCC, and in some primary tumors. We detected a protein, slightly larger than recombinant hPL by western blotting using several antibodies, leading us to postulate that it represents an hPL variant ('hPL'). Furthermore, some monoclonal antibodies detected 'hPL' by immunohistochemistry in breast carcinomas but not in normal breast. However, further examination revealed that these antibodies were non-specific, as efficient suppression of CSH mRNA by shRNA did not abolish the 'hPL' band. Custom-made monoclonal antibodies against recombinant hPL detected hPL of the correct size in placental lysate and hPL-overexpressing BCC, but not in unmodified cells or primary carcinomas. hPL protein was detected only when mRNA was increased several thousand fold. CONCLUSIONS: We call into question previous reports of hPL expression in breast cancer which relied on mRNA levels as surrogates for protein and/or used improperly validated antibodies to measure hPL protein levels. Our data suggests that an inhibitory mechanism(s) prevents translation of CSH mRNA in breast cancer when not highly expressed. The mechanism by which translation of CSH mRNA is inhibited is intriguing and should be further investigated.

HDAC9 knockout mice are protected from adipose tissue dysfunction and systemic metabolic disease during high-fat feeding.

During chronic caloric excess, adipose tissue expands primarily by enlargement of individual adipocytes, which become stressed with lipid overloading, thereby contributing to obesity-related disease. Although adipose tissue contains numerous preadipocytes, differentiation into functionally competent adipocytes is insufficient to accommodate the chronic caloric excess and prevent adipocyte overloading. We report for the first time that a chronic high-fat diet (HFD) impairs adipogenic differentiation, leading to accumulation of inefficiently differentiated adipocytes with blunted expression of adipogenic differentiation-specific genes. Preadipocytes from these mice likewise exhibit impaired adipogenic differentiation, and this phenotype persists during in vitro cell culture. HFD-induced impaired adipogenic differentiation is associated with elevated expression of histone deacetylase 9 (HDAC9), an endogenous negative regulator of adipogenic differentiation. Genetic ablation of HDAC9 improves adipogenic differentiation and systemic metabolic state during an HFD, resulting in diminished weight gain, improved glucose tolerance and insulin sensitivity, and reduced hepatosteatosis. Moreover, compared with wild-type mice, HDAC9 knockout mice exhibit upregulated expression of beige adipocyte marker genes, particularly during an HFD, in association with increased energy expenditure and adaptive thermogenesis. These results suggest that targeting HDAC9 may be an effective strategy for combating obesity-related metabolic disease.

Human coronary artery perivascular adipocytes overexpress genes responsible for regulating vascular morphology, inflammation, and hemostasis.

Inflammatory cross talk between perivascular adipose tissue and the blood vessel wall has been proposed to contribute to the pathogenesis of atherosclerosis. We previously reported that human perivascular (PV) adipocytes exhibit a proinflammatory phenotype and less adipogenic differentiation than do subcutaneous (SQ) adipocytes. To gain a global view of the genomic basis of biologic differences between PV and SQ adipocytes, we performed genome-wide expression analyses to identify differentially expressed genes between adipocytes derived from human SQ vs. PV adipose tissues. Although >90% of well-expressed genes were similarly regulated, we identified a signature of 307 differentially expressed genes that were highly enriched for functions associated with the regulation of angiogenesis, vascular morphology, inflammation, and blood clotting. Of the 156 PV upregulated genes, 59 associate with angiogenesis, vascular biology, or inflammation, noteworthy of which include TNFRSF11B (osteoprotegerin), PLAT, TGFB1, THBS2, HIF1A, GATA6, and SERPINE1. Of 166 PV downregulated genes, 21 associated with vascular biology and inflammation, including ANGPT1, ANGPTL1, and VEGFC. Consistent with the emergent hypothesis that PV adipocytes differentially regulate angiogenesis and inflammation, cell culture-derived adipocyte-conditioned media from PV adipocytes strongly enhanced endothelial cell tubulogenesis and monocyte migration compared with media from SQ adipocytes. These findings demonstrate that PV adipocytes have the potential to significantly modulate vascular inflammatory crosstalk in the setting of atherosclerosis by their ability to signal to both endothelial and inflammatory cells.

Nitric oxide bioavailability and adiponectin production in chronic systolic heart failure: relation to severity of cardiac dysfunction.

Adiponectin is an anti-inflammatory, antiatherogenic adipokine elevated in heart failure (HF) that may protect against endothelial dysfunction by influencing underlying nitric oxide bioavailability. In this study, we examine the relationship between plasma adiponectin levels and measures of nitric oxide bioavailability and myocardial performance in patients with chronic systolic HF. In 139 ambulatory patients with stable, chronic systolic HF (left ventricular [LV] ejection fraction ≤40%, New York Heart Association class I to IV), we measured plasma levels of adiponectin, asymmetric dimethylarginine (ADMA), and global arginine bioavailability (GABR), and performed comprehensive echocardiography with assessment of cardiac structure and performance. Adverse events (all-cause mortality or cardiac transplantation) were prospectively tracked for a median of 39 months. Plasma adiponectin levels directly correlated with plasma ADMA levels (Spearman's r = 0.41, P < 0.001) and aminoterminal pro-B-type natriuretic peptide (NT-proBNP) levels (r = 0.55, P < 0.001), inversely correlated with GABR (r = -0.39, P < 0.001), and were not associated with high-sensitivity C-reactive protein (P = 0.81) or myeloperoxidase (P = 0.07). Interestingly, increased plasma adiponectin levels remained positively correlated with plasma ADMA levels only in patients with elevated NT-proBNP levels (r = 0.33, P = 0.009). Higher plasma adiponectin levels were associated with worse LV diastolic dysfunction (rank sums P = 0.002), right ventricular (RV) systolic dysfunction (rank sums P = 0.002), and RV diastolic dysfunction (rank sums P = 0.011), but not after adjustment for plasma ADMA and NT-proBNP levels. Plasma adiponectin levels predicted increased risk of adverse clinical events (hazard ratio, 95% confidence interval 1.45 [1.02-2.07], P = 0.038) but not after adjustment for plasma ADMA and NT-proBNP levels, or echocardiographic indices of diastolic or RV systolic dysfunction. In patients with chronic systolic HF, adiponectin production is more closely linked with nitric oxide bioavailability than inflammation, and appears to be more robust in the setting of cardiac dysfunction or elevated natriuretic peptide levels.

Heart rate decrease during crizotinib treatment and potential correlation to clinical response.

BACKGROUND: Crizotinib is used for the treatment of advanced anaplastic lymphoma kinase (ALK)-rearranged nonsmall cell lung cancer (NSCLC). Sinus bradycardia (SB) is a side effect listed in its package insert. We investigated the frequency and timing of SB, patient characteristics associated with SB during crizotinib treatment, and potential correlation between heart rate (HR) changes and clinical response to crizotinib. METHODS: A retrospective chart review was conducted of the timing and frequency of SB, patient characteristics, and clinical response of patients to crizotinib treatment. RESULTS: Forty-twp patients who had ALK-rearranged or mesenchymal epithelial transition (MET)-amplified NSCLC and received treatment with oral crizotinib 250 mg twice daily who were enrolled in 2 crizotinib trials (PROFILE 1001 and PROFILE 1005) were analyzed. There was an average decrease of 26.1 beats per minute (bpm) from the pretreatment HR among all patients during crizotinib treatment. Twenty-nine patients (69%) experienced at least 1 episode of SB (HR, <60 bpm). The average time to the lowest HR recorded was 18.6 weeks (range, 5-72 weeks). Patients who experienced SB were significantly older (aged 55.8 years vs 47.8 years; P = .0336), had a lower pretreatment HR (mean, 77.9 bpm vs 100.6 bpm; P = .002), and were on crizotinib longer (52.9 weeks vs 24.6 weeks; P = .0050) than patients who did not experience SB. The overall response rate (P = .0195) and the maximum tumor shrinkage (P = .0205) were significantly greater in patients who experienced SB. CONCLUSIONS: HR decrease is common during crizotinib treatment. It remains to be determined whether the correlation between HR decrease and clinical response to crizotinib reflects a biomarker of drug efficacy or a time/cumulative dose-dependent phenomenon.

Progressive rise in red cell distribution width is associated with disease progression in ambulatory patients with chronic heart failure.

BACKGROUND: Single red cell distribution width (RDW) assessment is a consistent prognostic marker of poor outcomes in heart failure as well as in other patient cohorts. The objective of this study was to determine the prognostic value of sequential RDW assessment in ambulatory patients with chronic heart failure. METHODS AND RESULTS: We reviewed 6,159 consecutive ambulatory patients with chronic heart failure between 2001-2006 and examined changes in RDW values from baseline to 1-year follow-up. Clinical, demographic, laboratory, and ICD-9 coding data were extracted from electronic health records, and all-cause mortality was followed over a mean follow-up of 4.4 ± 2.4 years. In this study cohort, median baseline RDW was 14.9%. RDW >16% at baseline (18.5% of cohort) was associated with a higher mortality rates than RDW ≤16%. For each +1% increment of baseline RDW, the risk ratio for all-cause mortality was 1.17 (95% confidence interval [CI] 1.15-1.19; P < .0001). At 12-month follow-up (n = 1,601), a large majority of subjects (68% in first tertile, 56% in second tertile of baseline RDW) showed rising RDW and correspondingly higher risk for all-cause mortality (risk ratio for +1% increase in changes in RDW was 1.08 (95% CI 1.03-1.13; P = .001). This effect was independent of anemia status or other baseline cardiac or renal indices, and particularly strong in those with lower baseline RDW. CONCLUSIONS: In our ambulatory cohort of patients with chronic heart failure, baseline and serial increases in RDW were associated with poor long-term outcomes independently from standard cardiac, hematologic, and renal indices.

Right atrial volume index in chronic systolic heart failure and prognosis.

OBJECTIVES: The aim of this study was to determine the relationship between right atrial volume index (RAVI) and right ventricular (RV) systolic and diastolic function, as well as long-term prognosis in patients with chronic systolic heart failure (HF). BACKGROUND: RV dysfunction is associated with poor prognosis in patients with HF, although echocardiographic assessment of RV systolic and diastolic dysfunction is challenging. The ability to visualize the RA allows a quantitative, highly reproducible assessment of the RA volume that can be indexed to body surface area. METHODS: The ADEPT (Assessment of Doppler Echocardiography for Prognosis and Therapy) trial enrolled 192 subjects with chronic systolic HF (left ventricular ejection fraction [LVEF]

Measuring impedance in congestive heart failure: current options and clinical applications.

Measurement of impedance is becoming increasingly available in the clinical setting as a tool for assessing hemodynamics and volume status in patients with heart failure. The 2 major categories of impedance assessment are the band electrode method and the implanted device lead method. The exact sources of the impedance signal are complex and can be influenced by physiologic effects such as blood volume, fluid, and positioning. This article provides a critical review of our current understanding and promises of impedance measurements, the techniques that have evolved, as well as the evidence and limitations regarding their clinical applications in the setting of heart failure management.

Relation of mechanical dyssynchrony with underlying cardiac structure and performance in chronic systolic heart failure: implications on clinical response to cardiac resynchronization.

AIMS: The aim of this study is to describe the relationship between ventricular mechanical dyssynchrony (VMD) and echocardiographic indices of cardiac remodelling. METHODS AND RESULTS: We evaluated 219 ambulatory patients with chronic systolic heart failure [left ventricular ejection fraction (LVEF) 40 ms and/or inter-VMD > 38 ms). In our study cohort, 59% of patients had evidence of dyssynchrony (including 44% with intra-VMD and 38% with inter-VMD, and 20% with both). Inter-VMD correlated with QRS width (r = 0.48, P < 0.0001) better than intra-VMD (r = 0.24, P < 0.001). Higher inter-VMD was associated with less restrictive filling patterns (rank sums P = 0.012) and larger left ventricular end-diastolic dimension (LVEDD, rank sums P = 0.020), but intra-VMD values were similar across diastolic stages and LVEDD tertiles. CONCLUSION: In chronic systolic heart failure, evidence of mechanical dyssynchrony is prevalent but the underlying cardiac structure and performance may influence the degree of inter-VMD more so than intra-VMD. Our data suggest that the extent of inter-VMD is directly related to the degree of dilatation of the heart but inversely to diastolic dysfunction.

Differential effects of arginine methylation on diastolic dysfunction and disease progression in patients with chronic systolic heart failure.

AIMS: To investigate the association of arginine methylation with myocardial function and prognosis in chronic systolic heart failure patients. METHODS AND RESULTS: Asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA), as well as N-mono-methylarginine (MMA) and methyl-lysine, were simultaneously measured by tandem mass spectrometry in 132 patients with chronic systolic heart failure with echocardiographic evaluation and follow-up. Increasing ADMA and SDMA levels were associated with elevated natriuretic peptide levels (both P < 0.001), and increasing SDMA levels were associated with worsening renal function (P < 0.001). Higher plasma levels of methylated arginine metabolites (but not methyl-lysine) were associated with the presence of left ventricular (LV) diastolic dysfunction (E/septal E', Spearman's r = 0.31-0.36, P < 0.001). Patients taking beta-blockers had lower ADMA levels than those not taking beta-blockers [0.42 (0.33, 0.50) vs. 0.51 (0.40, 0.58), P < 0.001]. Only increasing ADMA levels were associated with advanced right ventricular (RV) systolic dysfunction. Elevated ADMA levels remained a consistent independent predictor of adverse clinical events (hazard ratio = 1.64, 95% CI: 1.20-2.22, P = 0.002). CONCLUSION: In chronic systolic heart failure, accumulation of methylated arginine metabolites is associated with the presence of LV diastolic dysfunction. Among the methylated derivatives of arginine, ADMA provides the strongest independent prediction of disease progression and adverse long-term outcomes.

Impact of myocardial function on cystatin C measurements in chronic systolic heart failure.

BACKGROUND: The influence of myocardial function on plasma levels of cystatin C (CysC), a sensitive marker of renal function, in chronic systolic heart failure (HF) has not been well established. METHODS: We prospectively identified 139 subjects with stable, chronic HF (left ventricular ejection fraction < or = 35%) and measured plasma levels of CysC. We prospectively tracked patients' long-term adverse clinical outcomes (death, cardiac transplantation, and HF hospitalizations). RESULTS: Plasma levels of CysC were elevated in 41% of patients with preserved renal function and directly correlated with N-terminal prohormone brain natriuretic peptide (r = 0.57, P < .0001). There was a significant association between CysC and mitral E/septal E' ratio (r = 0.34, P < .001), right ventricular systolic dysfunction severity (r = 0.30, P < .001), and mitral regurgitation severity (r = 0.31, P < .001), but not left ventricular ejection fraction. At the cutoff of 1.23 mg/dL, CysC remains a significant independent risk factor for adverse clinical outcomes (hazard ratio 1.88, 95% confidence interval 1.15-3.09, P = .012) after adjusting for estimated glomerular filtration rate, left ventricular ejection fraction, and E/septal E'. CONCLUSION: CysC is associated with more advanced left ventricular diastolic dysfunction and right ventricular systolic dysfunction and remains an independent predictor of long-term prognosis in chronic systolic HF after adjusting for myocardial factors.

Evaluation and long-term prognosis of new-onset, transient, and persistent anemia in ambulatory patients with chronic heart failure.

OBJECTIVES: This study sought to determine the characteristics and long-term prognosis of anemia in ambulatory patients with chronic heart failure. BACKGROUND: Anemia is prevalent in heart failure, and may portend poor outcomes. METHODS: We reviewed 6,159 consecutive outpatients with chronic stable heart failure at baseline, short-term (3-month) follow-up, and long-term (6-month) follow-up between 2001 and 2006. Clinical, demographic, laboratory, and echocardiographic data were reviewed from electronic medical records. Mortality rates were determined from 6-month follow-up to end of study period. RESULTS: Prevalence of anemia (hemoglobin [Hb] <12 g/dl for men, <11 g/dl for women) was 17.2% in our cohort. Diabetes, B-natriuretic peptide, left ventricular ejection fraction, and estimated glomerular filtration rate were independent predictors of baseline anemia. Documented evaluation of anemia was found in only 3% of all anemic patients, and better in internal medicine than in cardiology clinics. At 6-month follow-up, new-onset anemia developed in 16% of patients without prior anemia, whereas 43% patients with anemia at baseline had resolution of their hemoglobin levels. Higher total mortality rates were evident in patients with persistent anemia (58% vs. 31%, p < 0.0001) or with incident anemia (45% vs. 31%, p < 0.0001) compared with those with without anemia at 6 months. CONCLUSIONS: These observations in a broad unselected outpatient cohort suggest that anemia in patients with heart failure is under-recognized and underevaluated. However, resolution of anemia was evident in up to 43% of patients who presented initially with anemia, and did not pose greater long-term risk for all-cause mortality. However, the presence of persistent anemia conferred poorest survival in patients with heart failure when compared with that of incident, resolved, or no anemia.

Prognostic value and echocardiographic determinants of plasma myeloperoxidase levels in chronic heart failure.

OBJECTIVES: The purpose of this study was to explore the relationship between myeloperoxidase (MPO) and cardiac structure, performance, and prognosis. BACKGROUND: Myeloperoxidase is an inflammatory marker that is elevated in patients with heart failure (HF) and cardiac dysfunction, with mechanistic links to plaque vulnerability and left ventricular (LV) remodeling. METHODS: We evaluated plasma MPO levels (CardioMPO, PrognostiX, Inc., Cleveland, Ohio) in 140 patients with chronic systolic HF (LV ejection fraction <35%) and examined the plasma MPO levels' relationships with echocardiographic indexes of systolic and diastolic performance, as well as long-term clinical outcomes (death, cardiac transplantation, or HF hospitalization). RESULTS: Within the overall cohort, increasing plasma MPO levels were associated with increasing likelihood of more advanced HF (restrictive diastolic stage, right ventricular systolic dysfunction > or =3+, and tricuspid regurgitation area > or =1.8 cm2). Plasma MPO levels were predictive of long-term clinical outcomes (risk ratio [95% confidence interval] = 3.35 [1.52 to 8.86]), even after adjustment for age, LV ejection fraction, plasma B-type natriuretic peptide (BNP), creatinine clearance, or diastolic stage. In receiver-operator characteristic curve analyses, addition of MPO to BNP testing augmented the predictive accuracy of future adverse clinical events (area under the curve 0.66 for BNP only [chi-square test = 12.9, p = 0.0003], and 0.70 for BNP plus MPO [chi-square test = 15.87, p = 0.0004]). CONCLUSIONS: In chronic systolic HF, elevated plasma MPO levels are associated with an increased likelihood of more advanced HF. Moreover, elevated plasma MPO levels within a HF subject seem to be predictive of increased adverse clinical outcomes.

Plasma myeloperoxidase levels in patients with chronic heart failure.

Increased oxidative stress and endothelial dysfunction are commonly observed in patients with chronic heart failure (HF). The relation between myeloperoxidase (MPO), an inflammatory marker with mechanistic links to plaque vulnerability and abnormal ventricular remodeling, and degrees of severity in chronic HF has not been reported. Plasma MPO levels were measured in 105 normal controls (no history of HF or left ventricular dysfunction) and 102 patients with chronic systolic HF (left ventricular ejection fraction <50%), and the relations among plasma MPO levels, plasma B-type natriuretic peptide levels, and the left ventricular ejection fraction were examined. Plasma MPO levels in patients with chronic systolic HF were significantly elevated compared with those of healthy controls (1,158 +/- 2,965 vs 204 +/- 139 pM, p <0.0001). Plasma MPO levels increased in parallel with increasing New York Heart Association class (p <0.0001) and were correlated with plasma B-type natriuretic peptide levels (Spearman's r = 0.39, p <0.0001). Levels of MPO were strongly associated with the prevalence of HF (unadjusted odds ratio 30.3, 95% confidence interval 11.1 to 94.5) and remained significant when adjusted for age and B-type natriuretic peptide (odds ratio 27.7, 95% confidence interval 3.6 to 371.1). In conclusion, in a cohort of patients with chronic HF, plasma MPO levels were elevated compared with those of normal controls and were associated with worsening functional class.

Nonreciprocity of counterpropagating signals in a monolithically integrated Sagnac interferometer.

We demonstrate nonlinearly induced nonreciprocity of counterpropagating waves in a monolithically integrated Sagnac interferometer that employs a semiconductor optical amplifier as the nonlinear element. We show that the dependence of the linewidth enhancement factor on charge injection can influence the third-order nonlinearity in the semiconductor gain medium to a surprisingly large degree. This effect is utilized to control the phases of the counterpropagating signals in the interferometer. A theoretical model is used to explain the experimental observations. We show that these effects have significant practical implications by demonstrating an all-optical controlled-NOT gate.

A novel fast optical switch based on two cascaded Terahertz Optical Asymmetric Demultiplexers (TOAD).

A novel optical switch based on cascading two terahertz optical asymmetric demultiplexers (TOAD) is presented. By utilizing the sharp edge of the asymmetric TOAD switching window profile, two TOAD switching windows are overlapped to produce a narrower aggregate switching window, not limited by the pulse propagation time in the SOA of the TOAD. Simulations of the cascaded TOAD switching window show relatively constant window amplitude for different window sizes. Experimental results on cascading two TOADs, each with a switching window of 8ps, but with the SOA on opposite sides of the fiber loop, show a minimum switching window of 2.7ps.