Aerobic Exercise Training-Induced Left Ventricular Hypertrophy Involves Regulatory MicroRNAs, Decreased Angiotensin-Converting Enzyme-Angiotensin II, and Synergistic Regulation of Angiotensin-Converting Enzyme 2-Angiotensin (1-7)

Aerobic exercise training leads to a physiological, nonpathological left ventricular hypertrophy; however, the underlying biochemical and molecular mechanisms of physiological left ventricular hypertrophy are unknown. The role of microRNAs regulating the classic and the novel cardiac renin-angiotensin (Ang) system was studied in trained rats assigned to 3 groups: (1) sedentary; (2) swimming trained with protocol 1 (T1, moderate-volume training); and (3) protocol 2 (T2, high-volume training). Cardiac Ang I levels, Ang-converting enzyme (ACE) activity, and protein expression, as well as Ang II levels, were lower in T1 and T2; however, Ang II type 1 receptor mRNA levels (69% in T1 and 99% in T2) and protein expression (240% in T1 and 300% in T2) increased after training. Ang II type 2 receptor mRNA levels (220%) and protein expression (332%) were shown to be increased in T2. In addition, T1 and T2 were shown to increase ACE2 activity and protein expression and Ang (1-7) levels in the heart. Exercise increased microRNA-27a and 27b, targeting ACE and decreasing microRNA-143 targeting ACE2 in the heart. Left ventricular hypertrophy induced by aerobic training involves microRNA regulation and an increase in cardiac Ang II type 1 receptor without the participation of Ang II. Parallel to this, an increase in ACE2, Ang (1-7), and Ang II type 2 receptor in the heart by exercise suggests that this nonclassic cardiac renin-angiotensin system counteracts the classic cardiac renin-angiotensin system. These findings are consistent with a model in which exercise may induce left ventricular hypertrophy, at least in part, altering the expression of specific microRNAs targeting renin-angiotensin system genes. Together these effects might provide the additional aerobic capacity required by the exercised heart. (Hypertension. 2011;58:182-189.).

The Bypass Angioplasty Revascularization Investigation 2 Diabetes Randomized Trial of Different Treatment Strategies in Type 2 Diabetes Mellitus With Stable Ischemic Heart Disease Impact of Treatment Strategy on Cardiac Mortality and Myocardial Infarction

Background-The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial in 2368 patients with stable ischemic heart disease assigned before randomization to percutaneous coronary intervention or coronary artery bypass grafting strata reported similar 5-year all-cause mortality rates with insulin sensitization versus insulin provision therapy and with a strategy of prompt initial coronary revascularization and intensive medical therapy or intensive medical therapy alone with revascularization reserved for clinical indication(s). In this report, we examine the predefined secondary end points of cardiac death and myocardial infarction (MI). Methods and Results-Outcome data were analyzed by intention to treat; the Kaplan-Meier method was used to assess 5-year event rates. Nominal P values are presented. During an average 5.3-year follow-up, there were 316 deaths (43% were attributed to cardiac causes) and 279 first MI events. Five-year cardiac mortality did not differ between revascularization plus intensive medical therapy (5.9%) and intensive medical therapy alone groups (5.7%; P = 0.38) or between insulin sensitization (5.7%) and insulin provision therapy (6%; P = 0.76). In the coronary artery bypass grafting stratum (n = 763), MI events were significantly less frequent in revascularization plus intensive medical therapy versus intensive medical therapy alone groups (10.0% versus 17.6%; P = 0.003), and the composite end points of all-cause death or MI (21.1% versus 29.2%; P = 0.010) and cardiac death or MI (P = 0.03) were also less frequent. Reduction in MI (P = 0.001) and cardiac death/MI (P = 0.002) was significant only in the insulin sensitization group. Conclusions-In many patients with type 2 diabetes mellitus and stable ischemic coronary disease in whom angina symptoms are controlled, similar to those enrolled in the percutaneous coronary intervention stratum, intensive medical therapy alone should be the first-line strategy. In patients with more extensive coronary disease, similar to those enrolled in the coronary artery bypass grafting stratum, prompt coronary artery bypass grafting, in the absence of contraindications, intensive medical therapy, and an insulin sensitization strategy appears to be a preferred therapeutic strategy to reduce the incidence of MI. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00006305. (Circulation. 2009;120:2529-2540.)

Insertion/deletion polymorphism of the bradykinin type 2 receptor gene influence diastolic blood pressure

The contribution of kinins to the beneficial effects in cardiovascular risk reductions remains unclear. In this context, the present study examined whether the +9bp/-9 bp polymorphism in bradykinin type 2 receptor gene, predicts hypertension risk in a large urban Brazilian population. Our finding indicated that the -9 bp allele may contribute to hypertension because of increased diastolic pressure.

Updated Clinical Classification of Pulmonary Hypertension

The aim of a clinical classification of pulmonary hypertension (PH) is to group together different manifestations of disease sharing similarities in pathophysiologic mechanisms, clinical presentation, and therapeutic approaches. In 2003, during the 3rd World Symposium on Pulmonary Hypertension, the clinical classification of PH initially adopted in 1998 during the 2nd World Symposium was slightly modified. During the 4th World Symposium held in 2008, it was decided to maintain the general architecture and philosophy of the previous clinical classifications. The modifications adopted during this meeting principally concern Group 1, pulmonary arterial hypertension (PAH). This subgroup includes patients with PAH with a family history or patients with idiopathic PAH with germline mutations (e. g., bone morphogenetic protein receptor-2, activin receptor-like kinase type 1, and endoglin). In the new classification, schistosomiasis and chronic hemolytic anemia appear as separate entities in the subgroup of PAH associated with identified diseases. Finally, it was decided to place pulmonary venoocclusive disease and pulmonary capillary hemangiomatosis in a separate group, distinct from but very close to Group 1 (now called Group 1`). Thus, Group 1 of PAH is now more homogeneous. (J Am Coll Cardiol 2009;54:S43-54) (C) 2009 by the American College of Cardiology Foundation

Pressure-Frequency Sensing Subxiphoid Access System for Use in Percutaneous Cardiac Electrophysiology: Prototype Design and Pilot Study Results

We have designed, built, and tested an early prototype of a novel subxiphoid access system intended to facilitate epicardial electrophysiology, but with possible applications elsewhere in the body. The present version of the system consists of a commercially available insertion needle, a miniature pressure sensor and interconnect tubing, read-out electronics to monitor the pressures measured during the access procedure, and a host computer with user-interface software. The nominal resolution of the system is <0.1 mmHg, and it has deviations from linearity of <1%. During a pilot series of human clinical studies with this system, as well as in an auxiliary study done with an independent method, we observed that the pericardial space contained pressure-frequency components related to both the heart rate and respiratory rate, while the thorax contained components related only to the respiratory rate, a previously unobserved finding that could facilitate access to the pericardial space. We present and discuss the design principles, details of construction, and performance characteristics of this system.

Left ventricular Systolic function and outcome after in-hospital cardiac arrest

Background - The effect of prearrest left ventricular ejection fraction ( LVEF) on outcome after cardiac arrest is unknown. Methods and Results - During a 26-month period, Utstein-style data were prospectively collected on 800 consecutive inpatient adult index cardiac arrests in an observational, single-center study at a tertiary cardiac care hospital. Prearrest echocardiograms were performed on 613 patients ( 77%) at 11 +/- 14 days before the cardiac arrest. Outcomes among patients with normal or nearly normal prearrest LVEF ( >= 45%) were compared with those of patients with moderate or severe dysfunction ( LVEF < 45%) by chi(2) and logistic regression analyses. Survival to discharge was 19% in patients with normal or nearly normal LVEF compared with 8% in those with moderate or severe dysfunction ( adjusted odds ratio, 4.8; 95% confidence interval, 2.3 to 9.9; P < 0.001) but did not differ with regard to sustained return of spontaneous circulation ( 59% versus 56%; P = 0.468) or 24-hour survival ( 39% versus 36%; P = 0.550). Postarrest echocardiograms were performed on 84 patients within 72 hours after the index cardiac arrest; the LVEF decreased 25% in those with normal or nearly normal prearrest LVEF ( 60 +/- 9% to 45 +/- 14%; P < 0.001) and decreased 26% in those with moderate or severe dysfunction ( 31 +/- 7% to 23 +/- 6%, P < 0.001). For all patients, prearrest beta-blocker treatment was associated with higher survival to discharge ( 33% versus 8%; adjusted odds ratio, 3.9; 95% confidence interval, 1.8 to 8.2; P < 0.001). Conclusions - Moderate and severe prearrest left ventricular systolic dysfunction was associated with substantially lower rates of survival to hospital discharge compared with normal or nearly normal function.

Double-blind, Randomized placebo controlled trial of fulvestrant compared with exemestane after prior nonsteroidal aromatase inhibitor therapy in postmenopausal women with hormone receptor-positive, advanced breast cancer: Results from EFECT

Purpose The third-generation nonsteroidal aromatase inhibitors (AIs) are increasingly used as adjuvant and first-line advanced therapy for postmenopausal, hormone receptor-positive (HR +) breast cancer. Because many patients subsequently experience progression or relapse, it is important to identify agents with efficacy after AI failure. Materials and Methods Evaluation of Faslodex versus Exemestane Clinical Trial (EFECT) is a randomized, double-blind, placebo controlled, multicenter phase III trial of fulvestrant versus exemestane in postmenopausal women with HR + advanced breast cancer (ABC) progressing or recurring after nonsteroidal AI. The primary end point was time to progression (TTP). A fulvestrant loading-dose (LD) regimen was used: 500 mg intramuscularly on day 0, 250 mg on days 14, 28, and 250 mg every 28 days thereafter. Exemestane 25 mg orally was administered once daily. Results A total of 693 women were randomly assigned to fulvestrant (n = 351) or exemestane ( n = 342). Approximately 60% of patients had received at least two prior endocrine therapies. Median TTP was 3.7 months in both groups ( hazard ratio = 0.963; 95% CI, 0.819 to 1.133; P = .6531). The overall response rate ( 7.4% v 6.7%; P = .736) and clinical benefit rate ( 32.2% v 31.5%; P = .853) were similar between fulvestrant and exemestane respectively. Median duration of clinical benefit was 9.3 and 8.3 months, respectively. Both treatments were well tolerated, with no significant differences in the incidence of adverse events or quality of life. Pharmacokinetic data confirm that steady-state was reached within 1 month with the LD schedule of fulvestrant. Conclusion Fulvestrant LD and exemestane are equally active and well-tolerated in a meaningful proportion of postmenopausal women with ABC who have experienced progression or recurrence during treatment with a nonsteroidal AI.

Treatment with trastuzumab for 1 year after adjuvant chemotherapy in patients with HER2-positive early breast cancer: a 4-year follow-up of a randomised controlled trial

Background Treatment with adjuvant trastuzumab for 1 year improves disease-free survival and overall survival in patients with human epidermal growth factor receptor 2 (HER2)-positive early breast cancer. We aimed to assess disease-free survival and overall survival after a median follow-up of 4 years for patients enrolled on the Herceptin Adjuvant (HERA) trial. Methods The HERA trial is an international, multicentre, randomised, open-label, phase 3 trial comparing treatment with trastuzumab for 1 and 2 years with observation after standard neoadjuvant, adjuvant chemotherapy, or both in patients with HER2-positive early breast cancer. The primary endpoint was disease-free survival. After a positive first interim analysis at a median follow-up of 1 year for the comparison of treatment with trastuzumab for 1 year with observation, event-free patients in the observation group were allowed to cross over to receive trastuzumab. We report trial outcomes for the 1-year trastuzumab and observation groups at a median follow-up of 48.4 months (IQR 42.0-56.5) and assess the effect of the extensive crossover to trastuzumab. Our analysis was by intention-to-treat. The HERA trial is registered with the European Clinical Trials Database, number 2005-002385-11. Findings The HERA trial population comprised 1698 patients randomly assigned to the observation group and 1703 to the 1-year trastuzumab group. Intention-to-treat analysis of disease-free survival showed a significant benefit in favour of patients in the 1-year trastuzumab group (4-year disease-free survival 78.6%) compared with the observation group (4-year disease-free survival 72.2%; hazard ratio [HR] 0.76; 95% CI 0.66-0.87; p<0.0001). Intention-to-treat analysis of overall survival showed no significant difference in the risk of death (4-year overall survival 89.3% vs 87.7%, respectively; HR 0.85; 95% CI 0.70-1.04; p=0.11). Overall, 885 patients (52%) of the 1698 patients in the observation group crossed over to receive trastuzumab, and began treatment at median 22.8 months (range 4.5-52.7) from randomisation. In a non-randomised comparison, patients in the selective-crossover cohort had fewer disease-free survival events than patients remaining in the observation group (adjusted HR 0.68; 95% CI 0.51-0.90; p=0.0077). Higher incidences of grade 3-4 and fatal adverse events were noted on 1-year trastuzumab than in the observation group. The most common grade 3 or 4 adverse events, each in less than 1% of patients, were congestive cardiac failure, hypertension, arthralgia, back pain, central-line infection, hot flush, headache, and diarrhoea. Interpretation Treatment with adjuvant trastuzumab for 1 year after chemotherapy is associated with significant clinical benefit at 4-year median follow-up. The substantial selective crossover of patients in the observation group to trastuzumab was associated with improved outcomes for this cohort.

Inhibition of angiotensin II receptor 1 limits tumor-associated angiogenesis and attenuates growth of murine melanoma

Purpose We evaluated the involvement of angiotensin II (AngII)-dependent pathways in melanoma growth, through the pharmacological blockage of AT1 receptor by the antihypertensive drug losartan (LOS). Results We showed immunolabeling for both AngII and the AT1 receptor within the human melanoma microenvironment. Like human melanomas, we showed that murine melanomas also express the AT1 receptor. Growth of murine melanoma, both locally and at distant sites, was limited in mice treated with LOS. The reduction in tumor growth was accompanied by a twofold decrease in tumorassociated microvessel density and by a decrease in CD31 mRNA levels. While no differences were found in the VEGF expression levels in tumors from treated animals, reduction in the expression of the VEGFR1 (Flt-1) at the mRNA and protein levels was observed. We also showed downregulation of mRNA levels of both Flt-4 and its ligand, VEGF-C. Conclusions Together, these results show that blockage of AT1 receptor signaling may be a promising anti-tumor strategy, interfering with angiogenesis by decreasing the expression of angiogenic factor receptors.

Hyperdopaminergia and NMDA Receptor Hypofunction Disrupt Neural Phase Signaling

Neural phase signaling has gained attention as a putative coding mechanism through which the brain binds the activity of neurons across distributed brain areas to generate thoughts, percepts, and behaviors. Neural phase signaling has been shown to play a role in various cognitive processes, and it has been suggested that altered phase signaling may play a role in mediating the cognitive deficits observed across neuropsychiatric illness. Here, we investigated neural phase signaling in two mouse models of cognitive dysfunction: mice with genetically induced hyperdopaminergia [dopamine transporter knock-out (DAT-KO) mice] and mice with genetically induced NMDA receptor hypofunction [NMDA receptor subunit-1 knockdown (NR1-KD) mice]. Cognitive function in these mice was assessed using a radial-arm maze task, and local field potentials were recorded from dorsal hippocampus and prefrontal cortex as DAT-KO mice, NR1-KD mice, and their littermate controls engaged in behavioral exploration. Our results demonstrate that both DAT-KO and NR1-KD mice display deficits in spatial cognitive performance. Moreover, we show that persistent hyperdopaminergia alters interstructural phase signaling, whereas NMDA receptor hypofunction alters interstructural and intrastructural phase signaling. These results demonstrate that dopamine and NMDA receptor dependent glutamate signaling play a critical role in coordinating neural phase signaling, and encourage further studies to investigate the role that deficits in phase signaling play in mediating cognitive dysfunction.

Expression of activated mutants of the human interleukin-3/interleukin-5 granulocyte-macrophage colony-stimulating factor receptor common beta subunit in primary hematopoietic cells induces factor-independent proliferation and differentiation

To date, several activating mutations have been discovered in the common signal-transducing subunit (h beta c) of the receptors for human granulocyte-macrophage colony-stimulating factor, interleukin-3, and interleukin-5. Two of these, Fl Delta and 1374N, result in a 37 amino acid duplication and a single amino acid substitution in the extracellular domain of h beta c, respectively. A third, V449E, results in a single amino acid substitution in the transmembrane domain, Previous studies comparing the activity of these mutants in different hematopoietic cell lines imply that the transmembrane and extracellular mutations act by different mechanisms and suggest the requirement for cell type-specific molecules in signalling. To characterize the ability of these mutant hpc subunits to mediate growth and differentiation of primary cells and hence investigate their oncogenic potential, we have expressed all three mutants in primary murine hematopoietic cells using retroviral transduction. It is shown that, whereas expression of either extracellular hpc mutant confers factor-independent proliferation and differentiation on cells of the neutrophil and monocyte lineages only, expression of the transmembrane mutant does so on these lineages as well as the eosinophil, basophil, megakaryocyte, and erythroid lineages, Factor-independent myeloid precursors expressing the transmembrane mutant display extended proliferation in liquid culture and in some cases yielded immortalized cell lines. (C) 1997 by The American Society of Hematology.

Proposal for the interaction of non-conventional partial agonists and catecholamines with the 'putative beta(4)-adrenoceptor' in mammalian heart

1. Evidence for a 'putative beta(4)-adrenoceptor' originated over 20 years ago when cardiostimulant effects were observed to nonconventional partial agonists, These agonists were originally described as beta(1)- and beta(2)-adrenoceptor antagonists; however, they cause cardiostimulant effects at much higher concentrations than those required to block beta(1)- and beta(2)-adrenoceptors. Cardiostimulant effects of non-conventional partial agonists have been observed in mouse, rat, guinea-pig, cat, ferret and human heart tissues, 2. The receptor is expressed in several heart regions, including the sinoatrial node, atrium and ventricle, 3. The receptor is resistant to blockade by most antagonists that possess high affinity for beta(1)- and beta(2)- adrenoceptors, but is blocked with moderate affinity by (-)-bupranolol and CGP 20712A. 4. The receptor is pharmacologically distinct from the beta(3)-adrenoceptor. Micromolar concentrations of beta(3)-adrenoceptor agonists have no agonist or blocking activity, The receptor is also resistant to blockade by a beta(3)-adrenoceptor-selective antagonist. 5. The receptor mediates increases in cAMP levels and cAMP-dependent protein kinase (PK) A activity in cardiac tissues. Phosphodiesterase inhibition potentiates the positive chronotropic and inotropic effects of non-conventional partial agonists. 6. The receptor mediates hastening of atrial and ventricular relaxation, which is consistent with involvement of a cAMP-dependent pathway. 7. The non-conventional partial agonist (-)-[H-3]-CGP 12177A labels the cardiac putative beta(4)-adrenoceptor, Non-conventional partial agonists compete for binding with affinities that are closely similar to their agonist potencies, Catecholamines compete for binding in a stereoselective manner with a rank order of affinity of (-)-R0363 > (-)-isoprenaline > (-)-noradrenaline greater than or equal to (-)-adrenaline much greater than (-)-isoprenaline, suggesting that catecholamines can interact with the receptor. 8. The putative beta(4)-adrenoceptor appears to be coupled to the G(s)-adenylyl cyclase system, which could serve as a guide to its future cloning, Activation of the receptor may plausibly improve diastolic function but could also mediate arrhythmias.

Concentration dependence of sodium permeation and sodium ion interactions in the cyclic AMP-gated channels of mammalian olfactory receptor neurons

The dependence of currents through the cyclic nucleotide-gated (CNG) channels of mammalian olfactory receptor neurons (ORNs) on the concentration of NaCl was studied in excised inside-out patches from their dendritic knobs using the patch-clamp technique. With a saturating concentration (100 mu M) of adenosine 3', 5'-cyclic monophosphate (cAMP), the changes in the reversal potential of macroscopic currents were studied at NaCl concentrations from 25 to 300 mM. In symmetrical NaCl solutions without the addition of divalent cations, the current-voltage relations were almost linear, reversing close to O mV. When the external NaCl concentration was maintained at 150 mM and the internal concentrations were varied, the reversal potentials of the cAMP-activated currents closely followed the Na+ equilibrium potential indicating that P-Cl/P-Na approximate to 0. However, at low external NaCl concentrations (less than or equal to 100 mM) there was some significant chloride permeability. Our results further indicated that Na+ currents through these channels: (i) did not obey the independence principle; (ii) showed saturation kinetics with K(m)s in the range of 100-150 mM and (iii) displayed a lack of voltage dependence of conductance in asymmetric solutions that suggested that ion-binding sites were situated midway along the channel. Together, these characteristics indicate that the permeation properties of the olfactory CNG channels are significantly different from those of photoreceptor CNG channels.

Expression of vitamin D receptor mRNA in the hippocampal formation of rats submitted to a model of temporal lobe epilepsy induced by pilocarpine

Vitamin D (VD), is a steroid hormone with multiple functions in the central nervous system (CNS), producing numerous physiological effects mediated by its receptor (VDR). Clinical and experimental studies have shown a link between VD dysfunction and epilepsy. Along these lines, the purpose of our work was to analyze the relative expression of VDR mRNA in the hippocampal formation of rats during the three periods of pilocarpine-induced epilepsy. Male Wistar rats were divided into five groups: (1) control group; rats that received saline 0.9%, i.p. and were killed 7 days after its administration (CTRL, n = 8), (2) SE group; rats that received pilocarpine and were killed 4 h after SE (SE, n = 8), (3) Silent group-7 days; rats that received pilocarpine and were killed 7 days after SE (SIL 7d, n = 8), (4) Silent group-14 days; rats that received pilocarpine and were killed 14 days after SE (SIL 14d, n = 8), (5) Chronic group; rats that received pilocarpine and were killed 60 days after the first spontaneous seizure, (chronic, n = 8). The relative expression of VDR mRNA was determined by real-time PCR. Our results showed an increase of the relative expression of VDR mRNA in the SIL 7 days, SIL 14 days and Chronic groups, respectively (0.060 +/- 0.024; 0.052 +/- 0.035; 0.085 +/- 0.055) when compared with the CTRL and SE groups (0.019 +/- 0.017; 0.019 +/- 0.025). These data suggest the VDR as a possible candidate participating in the epileptogenesis process of the pilocarpine model of epilepsy. (C) 2008 Elsevier Inc. All rights reserved.