C-Reactive Protein, Interleukin-6, Trimethylamine-N-Oxide, Syndecan-1, Nitric Oxide, and Tumor Necrosis Factor Receptor-1 in Heart Failure with Preserved Versus Reduced Ejection Fraction: a Meta-Analysis.

PURPOSE OF REVIEW: The purpose of this review was to synthesize the evidence on non-traditional biomarkers from proteomic and metabolomic studies that may distinguish heart failure (HF) with preserved ejection fraction (HFpEF) from heart failure with reduced ejection fraction (HFrEF) and non-HF. RECENT FINDINGS: Understanding the pathophysiology of HFpEF continues to be challenging. A number of inflammatory and metabolic biomarkers that have recently been suggested to be involved include C-reactive protein (CRP), interleukin-6 (IL-6), trimethylamine-N-oxide (TMAO), syndecan-1 (SDC-1), nitric oxide (NO), and tumor necrosis factor receptor-1 (TNFR-1). A systematic search was conducted using Medline, EMBASE, and Web of Science with search terms such as "HFpEF," "metabolomics," and "proteomics," and a meta-analysis was conducted. The results demonstrate significantly higher levels of TMAO, CRP, SDC-1, and IL-6 in HFpEF compared to controls without HF and significantly higher levels of TMAO and CRP in HFrEF compared to controls. The results further suggest that HFpEF might be distinguishable from HFrEF based on higher levels of IL-6 and lower levels of SDC-1 and NO. These data may reflect pathophysiological differences between HFpEF and HFrEF.

Hypocalcemia-Induced QT Interval Prolongation.

An 87-year-old man with a history of transcatheter aortic valve replacement, pulmonary hypertension, diastolic dysfunction with preserved systolic function, and myelofibrosis had a 12-lead ECG showed a prolonged QT interval of 508 ms with heart-rate correction placing it in the 99th percentile of the population. Reduction in the dose of furosemide and calcium supplementation increased serum calcium and shortened the QT interval. This case provides an opportunity to examine newer concepts for the understanding of the mechanisms by which hypocalcemia might induce QT prolongation. Hypocalcemia likely produces corrected QT interval prolongation primarily through a calcium-dependent inactivation (CDI) mechanism on the L-type calcium channel (LTCC). Lower extracellular calcium leads to a decreased ICaL, subsequently causing intracellular calcium to take longer to reach the critical threshold to induce CDI of the LTCC. The resulting prolonged repolarization of the ventricular myocyte can lead to early after-depolarizations and ensuing life-threatening ventricular arrhythmias. Genetic polymorphisms in Ca2+-binding protein calmodulin which can prolong QT, underscore the role for disturbances of intracellular myocardial calcium handling in arrhythmogenesis. Hypocalcemia is an under-recognized cause of QT prolongation and should be taken into careful consideration in patients presenting with incidental findings of a prolonged QT interval.

The utility of growth differentiation factor-15, galectin-3, and sST2 as biomarkers for the diagnosis of heart failure with preserved ejection fraction and compared to heart failure with reduced ejection fraction: a systematic review.

The objective was to evaluate the diagnosis of heart failure with preserved ejection fraction (HFpEF) using the biomarkers, growth differentiation factor-15 (GDF-15), galectin-3 (Gal-3), and soluble ST2 (sST2), and to determine whether they can differentiate HFpEF from heart failure with reduced ejection fraction (HFrEF). Medline and Embase databases were searched with the terms diastolic heart failure or HFpEF, biomarkers, and diagnosis, limited to years 2000 to 2019. There were significantly and consistently higher levels of GDF-15, Gal-3, and sST2 in HFpEF compared to no heart failure. Importantly, the magnitude of the increase in GDF-15 or Gal-3 and possibly sST2,correlated with a greater degree of diastolic dysfunction. There were no significant differences between GDF-15, Gal-3, and sST2 in patients with HFpEF vs HFrEF. In the studies assessing these three biomarkers, BNP was significantly greater in heart failure than controls. Furthermore, BNP was significantly higher in HFrEF compared to HFpEF. The diagnostic utility of GDF-15, Gal-3, and sST2 compared to BNP was evaluated by comparing ROC curves. The data supports the contention that to distinguish HFpEF from HFrEF, an index is needed that incorporates GDF-15, Gal-3, or sST2 as well as BNP. The three biomarkers GDF-15, Gal-3, or sST2 can identify patients with HFpEF compared to individuals without heart failure but cannot differentiate HFpEF from HFrEF. BNP is higher in and is better at differentiating HFrEF from HFpEF. Indices that incorporate GDF-15, Gal-3, or sST2 as well as BNP show promise in differentiating HFpEF from HFrEF.

Hypoxia-inducible factor 1-alpha (HIF-1α) as a factor mediating the relationship between obesity and heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF), a common condition with an increased mortality, is strongly associated with obesity and the metabolic syndrome. The latter two conditions are associated with increased epicardial fat that can extend into the heart. This review advances the proposition that hypoxia-inhibitory factor-1α (HIF-1α) maybe a key factor producing HFpEF. HIF-1α, a highly conserved transcription factor that plays a key role in tissue response to hypoxia, is increased in adipose tissue in obesity. Increased HIF-1α expression leads to expression of a potent profibrotic transcriptional programme involving collagen I, III, IV, TIMP, and lysyl oxidase. The net effect is the formation of collagen fibres leading to fibrosis. HIF-1α is also responsible for recruiting M1 macrophages that mediate obesity-associated inflammation, releasing IL-6, MCP-1, TNF-α, and IL-1ß with increased expression of thrombospondin, pro α2 (I) collagen, transforming growth factor ß, NADPH oxidase, and connective tissue growth factor. These factors can accelerate cardiac fibrosis and impair cardiac diastolic function. Inhibition of HIF-1α expression in adipose tissue of mice fed a high-fat diet suppressed fibrosis and reduces inflammation in adipose tissue. Delineation of the role played by HIF-1α in obesity-associated HFpEF may lead to new potential therapies.

Gene expression and gene associations during the development of heart failure with preserved ejection fraction in the Dahl salt sensitive model of hypertension.

Gene expression and associations were examined in a model of heart failure with preserved ejection fraction (HFpEF), a condition with minimal effective treatment. Genes with at least two studies showing significant changes in Dahl rat with heart failure were examined by meta-analysis. Significantly increased in expression were iNOS, p47phox, ADM, ANP, OPN, ACE, MCP-1, GP91PHOX, ICAM-1, TGF-ß1, CTGF, ET-1, p22phox, ETB, BNP, ETA, MMP13, Col1a1, MMP2, TIMP1, Col3a1, Il-1ß, ß-MHC, ECE1, MMP14, AGT, and MMP9. In contrast, GLUT4, VEGF, eNOS, HIF-1α, and PGC1-α were significantly decreased in expression. The top biological process clusters identified in Database for Annotation, Visualization and Integrated Discovery, ToppGene, and PANTHER were collagen metabolic process, cellular ion homeostasis, regulation of cell migration, and response to decreased oxygen levels. These data suggest refocusing understanding of the pathophysiology of HFpEF to pathways involved in collagen metabolism, cell migration likely for inflammatory cells, and responses to decreased oxygen levels. Abbreviations Inducible nitric oxide synthase (INOS), neutrophil cytosolic factor 1 (p47phox), adrenomedullin (ADM), atrial natriuretic peptide (ANP), osteopontin (OPN/SPP1), angiotensin converting enzyme (ACE), monocyte chemotactic protein 1 (MCP-1), cytochrome b-245 beta polypeptide (gp91phox), intercellular adhesion molecule 1 (ICAM-1), transforming growth factor beta 1 (TGF-ß1), connective tissue growth factor (CTGF), endothelin-1 (ET-1), cytochrome B-245, alpha polypeptide (p22phox), endothelin receptor type B (ETB/EDNRB), brain natriuretic peptide (BNP), endothelin receptor type A (ETA/EDNRA), matrix metallopeptidase 13 (MMP13), type I collagen (Col1a1), matrix metallopeptidase 2 (MMP2), TIMP metallopeptidase inhibitor 1 (TIMP1), Type III collagen (Col3a1), interleukin 1 beta (IL-1ß), beta myocin heavy chain (ß-MHC), endothelin converting enzyme 1 (ECE1) matrix metallopeptidase 14 (MMP14), angiotensinogen (AGT), angiotensin II receptor Type 1 (AT1R), cytochrome C oxidase I (COX1), fms-like tyrosine kinase 1 (FLT1), TIMP metallopeptidase inhibitor 2 (TIMP2), phospholamban (PLN), vascular cell adhesion molecule 1 (VCAM1), extracellular matrix (ECM).

The Role Matrix Metalloproteinases in the Production of Aortic Aneurysm.

Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of aortic aneurysm because the histology of thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) is characterized by the loss of smooth muscle cells in the aortic media and the destruction of extracellular matrix (ECM). Furthermore, AAA have evidence of inflammation and the cellular elements involved in inflammation such as macrophages can produce and/or activate MMPs This chapter focuses on human aortic aneurysm that are not due to specific known genetic causes because this type of aneurysm is the more common type. This chapter will also focus on MMP protein expression rather than on genetic data which may not necessarily translate to increased MMP protein expression. There are supporting data that certain MMPs are increased in the aortic wall. For TAA, it is most notably MMP-1, -9, -12, and -14 and MMP-2 when a bicuspid aortic valve is present. For AAA, it is MMP-1, -2, -3, -9, -12, and -13. The data are weaker or insufficient for the other MMPs. Several studies of gene polymorphisms support MMP-9 for TAA and MMP-3 for AAA as potentially important factors. The signaling pathways in the aorta that can lead to MMP activation include JNK, JAK/stat, osteopontin, and AMP-activated protein kinase alpha2. Substrates in the human vasculature for MMP-3, MMP-9, or MMP-14 include collagen, elastin, ECM glycoprotein, and proteoglycans. Confirmed and potential substrates for MMPs, maintain aortic size and function so that a reduction in their content relative to other components of the aortic wall may produce a failure to maintain aortic size leading to dilatation and aneurysm formation.

Hypertension Canada's 2017 Guidelines for Diagnosis, Risk Assessment, Prevention, and Treatment of Hypertension in Adults.

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension. This year, we introduce 10 new guidelines. Three previous guidelines have been revised and 5 have been removed. Previous age and frailty distinctions have been removed as considerations for when to initiate antihypertensive therapy. In the presence of macrovascular target organ damage, or in those with independent cardiovascular risk factors, antihypertensive therapy should be considered for all individuals with elevated average systolic nonautomated office blood pressure (non-AOBP) readings ≥ 140 mm Hg. For individuals with diastolic hypertension (with or without systolic hypertension), fixed-dose single-pill combinations are now recommended as an initial treatment option. Preference is given to pills containing an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in combination with either a calcium channel blocker or diuretic. Whenever a diuretic is selected as monotherapy, longer-acting agents are preferred. In patients with established ischemic heart disease, caution should be exercised in lowering diastolic non-AOBP to ≤ 60 mm Hg, especially in the presence of left ventricular hypertrophy. After a hemorrhagic stroke, in the first 24 hours, systolic non-AOBP lowering to < 140 mm Hg is not recommended. Finally, guidance is now provided for screening, initial diagnosis, assessment, and treatment of renovascular hypertension arising from fibromuscular dysplasia. The specific evidence and rationale underlying each of these guidelines are discussed.

The Effect of Nicotine and Tobacco on Aortic Matrix Metalloproteinases in the Production of Aortic Aneurysm.

BACKGROUND: Aortic aneurysms (AAs) are without effective pharmacologic therapy, in clinical usage, in part because of the limited understanding of factors leading to AA development. OBJECTIVE: The objectives of this study were to examine the evidence that cigarette smoking induces AAs through altering matrix metalloproteinases (MMP) and the molecular biology/pharmacology that maybe involved in this effect. METHODS: A systematic search was conducted to identify studies that examined the links between cigarette smoke, MMP and AAs. RESULTS: Eleven studies were identified. There was consistency, between studies. They found that cigarette smoke, nicotine or tobacco products increased aortic dimension and the proportion of AAs. Nicotine and tobacco constituents induced MMPs: MMP-1, MMP-2, MMP-8, MMP-9 and MMP-12 but with different levels of consistency. The molecular mechanisms involved in the pathogenesis of cigarette-induced AA formation, ranked according to the consistency of evidence include JNK, AMPK-α2, Jak Stat, and mTOR/p70Sk and PTEN pathways. CONCLUSION: Nicotine and tobacco constituents translate the exposure to cigarette smoke into increased MMP expression through various molecular mechanisms whose interruption can form the basis for pharmacologic management of AAs.

The 2015 Canadian Hypertension Education Program recommendations for blood pressure measurement, diagnosis, assessment of risk, prevention, and treatment of hypertension.

The Canadian Hypertension Education Program reviews the hypertension literature annually and provides detailed recommendations regarding hypertension diagnosis, assessment, prevention, and treatment. This report provides the updated evidence-based recommendations for 2015. This year, 4 new recommendations were added and 2 existing recommendations were modified. A revised algorithm for the diagnosis of hypertension is presented. Two major changes are proposed: (1) measurement using validated electronic (oscillometric) upper arm devices is preferred over auscultation for accurate office blood pressure measurement; (2) if the visit 1 mean blood pressure is increased but < 180/110 mm Hg, out-of-office blood pressure measurements using ambulatory blood pressure monitoring (preferably) or home blood pressure monitoring should be performed before visit 2 to rule out white coat hypertension, for which pharmacologic treatment is not recommended. A standardized ambulatory blood pressure monitoring protocol and an update on automated office blood pressure are also presented. Several other recommendations on accurate measurement of blood pressure and criteria for diagnosis of hypertension have been reorganized. Two other new recommendations refer to smoking cessation: (1) tobacco use status should be updated regularly and advice to quit smoking should be provided; and (2) advice in combination with pharmacotherapy for smoking cessation should be offered to all smokers. The following recommendations were modified: (1) renal artery stenosis should be primarily managed medically; and (2) renal artery angioplasty and stenting could be considered for patients with renal artery stenosis and complicated, uncontrolled hypertension. The rationale for these recommendation changes is discussed.

Aortic wall stress in hypertension and ascending thoracic aortic aneurysms: implications for antihypertensive therapy.

The objective of this study was the evaluation of aortic wall stress in patients with ascending thoracic aortic aneurysms (TAA) because of the paucity of data to guide medical therapy for blood pressure (BP) management in TAA. Twelve men, age 67.4 ± 3.3 years (SEM) with hypertension and ascending TAA without other etiology, previous aortic surgery or associated significant aortic valve disease, had maximum dimensions of the ascending aorta measured from CT angiogram (CTa) and transthoracic echocardiogram (TTE) with aortic wall thickness measured on TTE. Wall stress (WS(σ)(P)) at peak systolic BP (SBP) was expressed by the equation: WS(σ)(P) = 2LCSA × SBP/MCSA, where LCSA is ascending aorta luminal cross-sectional area; MCSA is the surface area of the aortic wall cross sectional area considering aortic wall thickness. There was no significant difference in wall stress from TTE or CTa although mean wall stress was slightly larger when calculated from CTa. For each 5 mmHg increment in Systolic BP (SBP), there was a 3.9 kPa increase in wall stress that was 3.5 kPa for small aneurysms (40 to <45 mm) and 4.4 kPa for larger aneurysms (45-52 mm). There was a 33.0 ± 1.2 % reduction in wall stress when SBP went from 165 to 110 mmHg with a 21.0 ± 0.7 % reduction in wall stress found when SBP was reduced from 140 to 110 mmHg. These data, in patients with hypertension and ascending TAA suggest that meaningful reductions in aortic wall stress occur with reductions of SBP and this benefit extends to SBP levels <140 mmHg.

Differences in coronary blood flow in aortic regurgitation and systemic arterial hypertension have implications for diastolic blood pressure targets: a systematic review and meta-analysis.

The objective was to evaluate coronary blood flow (CBF) in patients with systemic arterial hypertension (HTN) and to compare it with CBF in patients with aortic regurgitation (AR). A systematic literature search was conducted using the reference terms "coronary blood flow" and either "aortic regurgitation" or "hypertension." The selection criteria included CBF measurement in a concomitant control group, except studies evaluating CBF with aortic-valve replacement surgery. Twenty-two studies met the inclusion criteria. There were 318 persons with HTN, with 185 controls; and 102 persons with AR, with 144 controls. Despite an overall increase in CBF in HTN, CBF per gram of left ventricular mass was significantly (P < 0.0001) reduced. In contrast, CBF per gram of left ventricular mass was significantly (P = 0.004) increased in AR. Aortic regurgitation was associated with a significant (P < 0.0001) increase in CBF during systole and away from diastole, in contrast to persons with HTN. Aortic-valve replacement reversed the increase in systolic CBF. These data suggest that patients with HTN are more vulnerable than patients with AR to lower diastolic blood pressure (DBP), because resting CBF is compromised in HTN. Furthermore, patients with HTN may not compensate for DBP reductions by shifting CBF to systole, such as can occur with the low DBP in AR. Lower DBP in patients with AR cannot be used to justify treating patients with HTN to similar DBP because of the dramatic differences in CBF between the 2 conditions.

Myocardial perfusion pressure in patients with hypertension and coronary artery disease: implications for DBP targets in hypertension management.

BACKGROUND: The target blood pressure (BP) in patients with hypertension and coronary artery disease (CAD) has been controversial. Whether patients with both diabetes mellitus and CAD should follow targets for either diabetes mellitus or CAD is uncertain. Focusing only on one determinant of coronary blood flow (CBF) - myocardial perfusion pressure (MPP) - coronary BP in patients with hypertension was used to estimate the impact of setting BP targets. METHODS: A consecutive series of 101 patients referred for coronary angiography for stable angina pectoris or possible CAD had BP measurements proximal and distal to coronary artery stenosis. Fractional flow reserve (FFR) was measured from adenosine-induced maximal hyperemia. DBP after the coronary stenosis was the MPP. The most severe coronary lesion for each person was selected. RESULTS: Of 101 patients, 65.0 ±â€Š10.6 years (mean ±â€ŠSD), there were 69 with hypertension and 33 with diabetes mellitus of whom 25 had diabetes mellitus along with hypertension. In hypertension, FFR was 0.83 ±â€Š0.08, range from 0.49 to 0.97, with 40% having FFR less than 0.8. There was a significant linear relationship between systemic DBP and MPP. CBF approximates zero with MMP of 50  mmHg under resting conditions and 40  mmHg with coronary vasodilatation. On the basis of our findings in hypertension, if DBP were 80, 70, 65 and 60  mmHg, 1.4, 7.1, 15.7 and 54.3%, respectively, of patients would have an MPP of less than 50  mmHg. The values were similar for patients with diabetes mellitus. CONCLUSION: In our patient group with moderate coronary artery stenosis, a target DBP of 60  mmHg or less would be associated with unacceptably low MPPs. In patients with diabetes mellitus, the presence and severity of CAD stenosis may be more important factor in setting BP targets for treatment of hypertension. Because the degree of coronary stenosis is unknown in most patients with hypertension and CAD, guideline recommendations should consider cautioning clinicians about the potential for myocardial ischaemia at low DBP.

The 2011 Canadian Hypertension Education Program recommendations for the management of hypertension: blood pressure measurement, diagnosis, assessment of risk, and therapy.

We updated the evidence-based recommendations for the diagnosis, assessment, prevention, and treatment of hypertension in adults for 2011. The major guideline changes this year are: (1) a recommendation was made for using comparative risk analogies when communicating a patient's cardiovascular risk; (2) diagnostic testing issues for renal artery stenosis were discussed; (3) recommendations were added for the management of hypertension during the acute phase of stroke; (4) people with hypertension and diabetes are now considered high risk for cardiovascular events if they have elevated urinary albumin excretion, overt kidney disease, cardiovascular disease, or the presence of other cardiovascular risk factors; (5) the combination of an angiotensin-converting enzyme (ACE) inhibitor and a dihydropyridine calcium channel blocker (CCB) is preferred over the combination of an ACE inhibitor and a thiazide diuretic in persons with diabetes and hypertension; and (6) a recommendation was made to coordinate with pharmacists to improve antihypertensive medication adherence. We also discussed the recent analyses that examined the association between angiotensin II receptor blockers (ARBs) and cancer.

Cardiometabolic risk in Canada: a detailed analysis and position paper by the cardiometabolic risk working group.

The concepts of "cardiometabolic risk," "metabolic syndrome," and "risk stratification" overlap and relate to the atherogenic process and development of type 2 diabetes. There is confusion about what these terms mean and how they can best be used to improve our understanding of cardiovascular disease treatment and prevention. With the objectives of clarifying these concepts and presenting practical strategies to identify and reduce cardiovascular risk in multiethnic patient populations, the Cardiometabolic Working Group reviewed the evidence related to emerging cardiovascular risk factors and Canadian guideline recommendations in order to present a detailed analysis and consolidated approach to the identification and management of cardiometabolic risk. The concepts related to cardiometabolic risk, pathophysiology, and strategies for identification and management (including health behaviours, pharmacotherapy, and surgery) in the multiethnic Canadian population are presented. "Global cardiometabolic risk" is proposed as an umbrella term for a comprehensive list of existing and emerging factors that predict cardiovascular disease and/or type 2 diabetes. Health behaviour interventions (weight loss, physical activity, diet, smoking cessation) in people identified at high cardiometabolic risk are of critical importance given the emerging crisis of obesity and the consequent epidemic of type 2 diabetes. Vascular protective measures (health behaviours for all patients and pharmacotherapy in appropriate patients) are essential to reduce cardiometabolic risk, and there is growing consensus that a multidisciplinary approach is needed to adequately address cardiometabolic risk factors. Health care professionals must also consider risk factors related to ethnicity in order to appropriately evaluate everyone in their diverse patient populations.

Identification and management of cardiometabolic risk in Canada: a position paper by the cardiometabolic risk working group (executive summary).

With the objectives of clarifying the concepts related to "cardiometabolic risk," "metabolic syndrome" and "risk stratification" and presenting practical strategies to identify and reduce cardiovascular risk in multiethnic patient populations, the Cardiometabolic Working Group presents an executive summary of a detailed analysis and position paper that offers a comprehensive and consolidated approach to the identification and management of cardiometabolic risk. The above concepts overlap and relate to the atherogenic process and development of type 2 diabetes. However, there is confusion about what these terms mean and how they can best be used to improve our understanding of cardiovascular disease treatment and prevention. The concepts related to cardiometabolic risk, pathophysiology, and strategies for identification and management (including health behaviours, pharmacotherapy, and surgery) in the multiethnic Canadian population are presented. "Global cardiometabolic risk" is proposed as an umbrella term for a comprehensive list of existing and emerging factors that predict cardiovascular disease and/or type 2 diabetes. Health behaviour interventions (weight loss, physical activity, diet, smoking cessation) in people identified at high cardiometabolic risk are of critical importance given the emerging crisis of obesity and the consequent epidemic of type 2 diabetes. Vascular protective measures (health behaviours for all patients and pharmacotherapy in appropriate patients) are essential to reduce cardiometabolic risk, and there is growing consensus that a multidisciplinary approach is needed to adequately address cardiometabolic risk factors. Health care professionals must also consider ethnicity-related risk factors in order to appropriately evaluate all individuals in their diverse patient populations.

Jumonji is a potential regulatory factor mediating nitric oxide-induced modulation of cardiac hypertrophy.

BACKGROUND AND OBJECTIVES: Jumonji (jmj) is the prototypical member of the jmj domain-containing protein family. It regulates the expression of several genes, in particular genes involved in cardiac cell growth in the embryonic heart. The function of jmj in the mature or developed heart, however, is unclear. RESULTS: We propose that JMJ domain 2A family may be involved in modulating the development of cardiac hypertrophy through interactions with cell cycle-regulatory proteins, specifically retinoblastoma protein, cyclin D and transcription factor E2F, that lead to cell growth. Because nitric oxide can block the development of cardiac hypertrophy and upregulate both jmj gene and protein expression, we propose that jmj is a novel regulatory factor mediating nitric oxide-induced modulation of cardiac hypertrophy. CONCLUSION: Jmj may be a critical, previously unrecognized factor that 'counteracts' the development of cardiac hypertrophy. Biotechnology approaches to increase its expression may be a potential therapeutic strategy to mitigate the increased cardiovascular morbidity and mortality associated with cardiac hypertrophy.

The role of p53 in nitric oxide-induced cardiomyocyte cell death.

The role of p53 in mediating nitric oxide (NO)-induced cell death remains uncertain. The exogenous NO donor S-nitrosoglutathione (GSNO) produced a concentration-dependent reduction in cell viability in embryonic chick cardiomyocytes in culture. Western blotting and immunocytochemistry for p53 showed that p53 was increased in whole cell lysates by GSNO: 0.001 mM GSNO led to 1.3 +/- 0.5-fold increase compared to control, and significantly (p < 0.05) increased to 1.6 +/- 0.2-fold after 0.01 mM GSNO. Higher GSNO concentrations did not further increase p53 protein expression despite producing significant increases in cell death. The p53 inhibitor pifithrin did not block GSNO-induced cell death. GSNO induced morphological changes of DNA fragmentation, nuclear condensation, and cell shrinkage. Pifithrin failed to block these morphologic changes, while it antagonized the similar cellular changes induced by adriamycin, which operates in part through p53. NO induced a concentration-dependent DNA damage. When assessed by the comet assay, the damage was 2.1 +/- 0.3-fold and 2.6 +/- 0.5-fold more than the control following 0.01 mM and 1.0 mM GSNO treatments, respectively. The DNA damage was not reduced by treatment with the pifithrin, which markedly reduced DNA damage induced by adriamycin. There was no p53 translocation to mitochondria, any major cytochrome c release from mitochondria, or change in mitochondrial membrane potential. Furthermore, cyclosporin A, which inhibits mitochondrial pore opening and cytochrome c loss, did not alter NO-induced cell death. Translocation of p53 from the cytosol to the nucleus occurred with a maximal increase of 2.9-fold in the nucleus following 1.0 mM GSNO for 24 h. These data indicate that in cardiomyocytes, NO induced marked DNA damage and translocation of p53 to the nucleus, suggesting that p53 is involved in the cellular response to NO, perhaps to modulate the genomic response to NO-induced cellular toxicity. NO-induced cell death, however, operates through p53-independent pathways, including a mitochondrial apoptotic pathway.

The 2006 Canadian Hypertension Education Program recommendations for the management of hypertension: Part II - Therapy.

OBJECTIVE: To provide updated, evidence-based recommendations for the management of hypertension in adults. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence from randomized, controlled trials and systematic reviews of trials was preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. For lifestyle interventions, blood pressure (BP) lowering was accepted as a primary outcome given the lack of long-term morbidity/mortality data in this field. For treatment of patients with kidney disease, the development of proteinuria or worsening of kidney function was also accepted as a clinically relevant primary outcome. EVIDENCE: MEDLINE searches were conducted from November 2004 to October 2005 to update the 2005 recommendations. In addition, reference lists were scanned and experts were contacted to identify additional published studies. All relevant articles were reviewed and appraised independently by content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: Lifestyle modifications to prevent and/or treat hypertension include the following: perform 30 min to 60 min of aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index of 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm for men and less than 88 cm for women); limit alcohol consumption to no more than 14 standard drinks per week in men or nine standard drinks per week in women; follow a diet that is reduced in saturated fat and cholesterol and that emphasizes fruits, vegetables and low-fat dairy products; restrict salt intake; and consider stress management in selected individuals. Treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and comorbid conditions. BP should be lowered to less than 140/90 mmHg in all patients, and to less than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease (regardless of the degree of proteinuria). Most adults with hypertension require more than one agent to achieve these target BPs. For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic hypertension with or without systolic hypertension include beta-blockers (in those younger than 60 years), angiotensin-converting enzyme (ACE) inhibitors (in nonblack patients), long-acting calcium channel blockers or angiotensin receptor antagonists. Other agents for first-line therapy for isolated systolic hypertension include long-acting dihydropyridine calcium channel blockers or angiotensin receptor antagonists. Certain comorbid conditions provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with diabetes mellitus, ACE inhibitors or angiotensin receptor antagonists (or in patients without albuminuria, thiazides or dihydropyridine calcium channel blockers) are appropriate first-line therapies; and in patients with nondiabetic chronic kidney disease, ACE inhibitors are recommended. All hypertensive patients should have their fasting lipids screened, and those with dyslipidemia should be treated using the thresholds, targets and agents recommended by the Canadian Hypertension Education Program Working Group on the management of dyslipidemia and the prevention of cardiovascular disease. Selected patients with hypertension, but without dyslipidemia, should also receive statin therapy and/or acetylsalicylic acid therapy. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the 45 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

The 2005 Canadian Hypertension Education Program recommendations for the management of hypertension: part II - therapy.

OBJECTIVE: To provide updated, evidence-based recommendations for the management of hypertension in adults. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence from randomized controlled trials and systematic reviews of trials was preferentially reviewed. While changes in cardiovascular morbidity and mortality were the primary outcomes of interest, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity/mortality data in this field, and for certain comorbid conditions, other relevant outcomes, such as development of proteinuria or worsening of kidney function, were considered. EVIDENCE: MEDLINE searches were conducted from November 2003 to October 2004 to update the 2004 recommendations. Reference lists were scanned, experts were contacted, and the personal files of the subgroup members and authors were used to identify additional published studies. All relevant articles were reviewed and appraised independently, using prespecified levels of evidence, by content and methodology experts. As per previous years, only studies that had been published in the peer-reviewed literature were included; evidence from abstracts, conference presentations and unpublished personal communications was not included. RECOMMENDATIONS: Lifestyle modifications to prevent and/or treat hypertension include the following: perform 30 min to 60 min of aerobic exercise on four to seven days of the week; maintain a healthy body weight (body mass index of 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm for men and less than 88 cm for women); limit alcohol consumption to no more than 14 units per week in men or nine units per week in women; follow a reduced fat, low cholesterol diet with an adequate intake of potassium, magnesium and calcium; restrict salt intake; and consider stress management (in selected individuals). Treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and any comorbid conditions. Blood pressure should be lowered to 140/90 mmHg or less in all patients, and to 130/80 mmHg or less in those with diabetes mellitus or chronic kidney disease. Most adults with hypertension require more than one agent to achieve target blood pressures. For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic hypertension with or without systolic hypertension include beta-blockers (in those younger than 60 years), angiotensin-converting enzyme (ACE) inhibitors (except in black patients), long-acting calcium channel blockers and angiotensin receptor antagonists. Other agents appropriate for first-line therapy for isolated systolic hypertension include long-acting dihydropyridine calcium channel blockers and angiotensin receptor antagonists. Certain comorbid conditions provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with diabetes mellitus, ACE inhibitors or angiotensin receptor antagonists (or thiazides in patients with diabetes mellitus without albuminuria) are appropriate first-line therapies; and in patients with nondiabetic chronic kidney disease, ACE inhibitors are recommended. All hypertensive patients should have their fasting lipids screened, and those with dyslipidemia should be treated using the thresholds, targets and agents recommended by the Canadian Hypertension Education Program Working Group on the management of dyslipidemia and the prevention of cardiovascular disease. Selected patients with hypertension, but without dyslipidemia, should also receive statin therapy and/or acetylsalicylic acid therapy. VALIDATION: All recommendations were graded according to the strength of the evidence and voted on by the 43 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Cytoskeletal actin degradation induced by lovastatin in cardiomyocytes is mediated through caspase-2.

The objective of this study was to test the hypothesis that cytoskeletal actin fragmentation is mediated through caspase-2, specifically examining the ability of a caspase-2 inhibitor to interfere with actin fragmentation, in comparison with a caspase-3 inhibitor. Cardiomyocytes were cultured from embryonic chick heart. The fine structural element of cellular F-actin was visualized by staining cardiomyocytes with NBD-phallacidin. Lovastatin induced a dramatic and concentration-dependent loss of intact F-actin. The selectivity of this effect of lovastatin was demonstrated by the absence of similar changes in F-actin when cardiomyocytes were treated with the apoptotic stimulus palmitate, the metabolism of which produces acetyl CoA, the early substrate of cholesterol synthesis, through the mevalonate pathway. FACS analysis of NBD-phallacidin-stained cells was used to quantify the amount of F-actin loss. Actin fragmentation produced by lovastatin was operative through a caspase-2 pathway, as the caspase-2 inhibitor, z-VDVAD-fmk, significantly blocked lovastatin-induced changes in F-actin, but the caspase-3 inhibitor, Ac-DEVD-CHO, did not. Interruption of the mevalonate pathway was in part responsible for lovastatin's action, as the downstream metabolite mevalonate partially reversed the effect of lovastatin on actin fragmentation. These data indicate a previously unrecognized link between cytoskeletal actin and caspase-2.