Publications by authors named "Brozovich F"

Aging is associated with cardiac contractile abnormalities, but the etiology of these contractile deficits is unclear. We hypothesized that cardiac contractile and regulatory protein expression is altered during aging. To investigate this possibility, left ventricular (LV) lysates were prepared from young (6 months) and old (24 months) Fischer344 rats.

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Vasodilatation in response to NO is a fundamental response of the vasculature, and during aging, the vasculature is characterized by an increase in stiffness and decrease in sensitivity to NO mediated vasodilatation. Vascular tone is regulated by the activation of smooth muscle and nonmuscle (NM) myosin, which are regulated by the activities of myosin light chain kinase (MLCK) and MLC phosphatase. MLC phosphatase is a trimeric enzyme with a catalytic subunit, myosin targeting subunit (MYPT1) and 20 kDa subunit of unknown function.

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Heart failure is a clinical syndrome characterized by the inability of the cardiovascular system to provide adequate cardiac output at normal filling pressures. This results in a clinical syndrome characterized by dyspnea, edema, and decreased exertional tolerance. Heart failure with preserved ejection fraction (HFpEF) is an increasingly common disease, and the incidence of HFpEF increases with age.

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Objective: To explore the transcriptomic differences between patients with hypertrophic cardiomyopathy (HCM) and controls.

Patients And Methods: RNA was extracted from cardiac tissue flash frozen at therapeutic surgical septal myectomy for 106 patients with HCM and 39 healthy donor hearts. Expression profiling of 37,846 genes was performed using the Illumina Human HT-12v3 Expression BeadChip.

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Both heart failure with reduced (HFrEF) and preserved (HFpEF) ejection fraction are associated with abnormalities of the vasculature, including a resting vasoconstriction and a decrease in sensitivity to nitric oxide (NO) mediated vasodilation. Vascular tone is controlled by the expression and activation of both smooth muscle (SM) and nonmuscle (NM) myosin, and NO mediated vasodilation is regulated by the expression of the leucine zipper positive (LZ+) isoform of the myosin targeting subunit (MYPT1) of myosin light chain phosphatase (MLCP). This study was designed to determine the expression of these contractile proteins in humans with HFrEF and HFpEF vs normal controls.

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Social anxiety disorder (SAD) has been shown to be associated with difficulty in the ability to vicariously share others' positive emotions (positive affective empathy). Mixed evidence also suggests potentially impaired recognition of the positive and negative emotions of others (cognitive empathy) and impaired or enhanced sharing of the negative emotions of others (negative affective empathy). Therefore, we examined whether two efficacious treatments for SAD, cognitive-behavioral group therapy (CBGT) and mindfulness-based stress reduction (MBSR), improve empathy in SAD relative to a wait-list condition and whether improvements in empathy mediate improvements in social anxiety.

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The number of patients with heart failure with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF) is increasing, and for HFpEF, no therapies have clinical benefit. It has been hypothesized that PKG attenuates pathological remodelling, and increasing cGMP would be beneficial for patients with HF. However, neither the RELAX nor NEAT-HFpEF trial showed benefit.

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Patients with heart failure are commonly divided into those with reduced ejection fraction (EF<40%) and those with preserved ejection fraction (HFpEF; EF>50%). For heart failure with reduced EF, a number of therapies have been found to improve patient morbidity and mortality, and treatment is guideline based. However for patients with HFpEF, no treatment has been found to have clinical benefit.

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There are two primary components that produce pulmonary arterial hypertension (PAH); aberrant structural changes (smooth muscle cell proliferation, smooth muscle cell hypertrophy, and the deposition of matrix proteins within the media of pulmonary arterial vessels), and excess vasoconstriction. However, in PAH, the target and aim of all current therapeutic agents is to reduce the contractility of the pulmonary vasculature; prostaglandins, phosphodiesterase inhibitors, guanylate cyclase stimulators, endothelin antagonists, NO inhalation and Rho kinase inhibitors all influence signaling pathways in the pulmonary vascular smooth muscle to decrease vasoconstriction, and hence, pulmonary vascular resistance (PVR). This review will therefore primarily focus on discussing the signaling pathways regulating contractility in pulmonary vascular smooth muscle, the mechanism for current treatments, as well as highlighting potential targets for the development of novel therapies.

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Social anxiety disorder (SAD) is associated with elevated negative and diminished positive affective experience. However, little is known about the way in which individuals with SAD perceive and respond emotionally to the naturally-unfolding negative and positive emotions of others, that is, cognitive empathy and affective empathy, respectively. In the present study, participants with generalized SAD (n = 32) and demographically-matched healthy controls (HCs; n = 32) completed a behavioral empathy task.

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Agonist stimulation of smooth muscle is known to activate RhoA/Rho kinase signaling, and Rho kinase phosphorylates the myosin targeting subunit (MYPT1) of myosin light chain (MLC) phosphatase at Thr696 and Thr853, which inhibits the activity of MLC phosphatase to produce a Ca independent increase in MLC phosphorylation and force (Ca sensitization). Alternative mRNA splicing produces four MYPT1 isoforms, which differ by the presence or absence of a central insert (CI) and leucine zipper (LZ). This study was designed to determine if Rho kinase differentially phosphorylates MYPT1 isoforms.

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The smooth muscle cell directly drives the contraction of the vascular wall and hence regulates the size of the blood vessel lumen. We review here the current understanding of the molecular mechanisms by which agonists, therapeutics, and diseases regulate contractility of the vascular smooth muscle cell and we place this within the context of whole body function. We also discuss the implications for personalized medicine and highlight specific potential target molecules that may provide opportunities for the future development of new therapeutics to regulate vascular function.

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Objective: The goal of this study was to investigate treatment outcome and mediators of cognitive-behavioral group therapy (CBGT) versus mindfulness-based stress reduction (MBSR) versus waitlist (WL) in patients with generalized social anxiety disorder (SAD).

Method: One hundred eight unmedicated patients (55.6% female; mean age = 32.

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The subjective experience of anxiety plays a central role in cognitive behavioral models of social anxiety disorder (SAD). However, much remains to be learned about the temporal dynamics of anxiety elicited by feared social situations. The aims of the current study were: (1) to compare anxiety trajectories during a speech task in individuals with SAD (n=135) versus healthy controls (HCs; n=47), and (2) to compare the effects of CBT on anxiety trajectories with a waitlist control condition.

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Background And Objectives: Difficulties with attentional control have long been thought to play a key role in anxiety and depressive disorders. However, the nature and extent of attentional control difficulties in social anxiety disorder (SAD) are not yet well understood. The current study was designed to assess whether attentional control for non-emotional information is impaired in SAD when taking comorbid depression into account.

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Phosphodiesterase-5 (PDE5) is highly expressed in the pulmonary vasculature, but its expression in the myocardium is controversial. Cyclic guanosine monophosphate (cGMP) activates protein kinase G (PKG), which has been hypothesized to blunt cardiac hypertrophy and negative remodeling in heart failure. Although PDE5 has been suggested to play a significant role in the breakdown of cGMP in cardiomyocytes and hence PKG regulation in the myocardium, the RELAX trial, which tested effect of PDE5 inhibition on exercise capacity in patients with heart failure with preserved ejection fraction (HFpEF) failed to show a beneficial effect.

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Objective: There is growing interest in the role of transdiagnostic processes in the onset, maintenance, and treatment of mental disorders (Nolen-Hoeksema & Watkins, 2011). Two such transdiagnostic processes-rumination and reappraisal-are the focus of the present study. The main objective was to examine the roles of rumination (thought to be harmful) and reappraisal (thought to be helpful) in adults with social anxiety disorder (SAD).

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The vascular response to NO is due, in part, to a Ca(2+) independent activation of myosin light chain (MLC) phosphatase, a trimeric enzyme of 20kDa, 38kDa catalytic and 110-130kDa myosin targeting (MYPT1) subunits. Alternative mRNA splicing produces MYPT1 isoforms that differ by the presence or absence of a central insert (CI) and a leucine zipper (LZ), and the presence of a LZ+ MYPT1 isoform is important for protein kinase G (PKG) mediated activation of MLC phosphatase. This study was designed to determine the molecular basis for the differential sensitivity of the vasculature to NO.

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Left ventricular assist device (LVAD) support has been used in the treatment of end-stage heart failure (HF), however use of anti-fibrotic co-therapies may improve prognosis. Natriuretic peptides (NPs) possess anti-fibrotic properties through their receptors, GC-A/GC-B/NPR-C. We sought to evaluate cardiac fibrosis and the endogenous NP system in end-stage HF with and without LVAD therapy and to assess the anti-fibrotic actions of the dual GC-A/-B activator CD-NP in vitro.

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While neurohumoral antagonists improve outcomes in heart failure (HF), cardiac remodeling and dysfunction progress and outcomes remain poor. Therapies superior or additive to standard HF therapy are needed. Pharmacologic mTOR inhibition by rapamycin attenuated adverse cardiac remodeling and dysfunction in experimental heart failure (HF).

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Pulmonary arterial hypertension (PAH) is associated with refractory vasoconstriction and impaired NO-mediated vasodilatation of the pulmonary vasculature. Vascular tone is regulated by light chain (LC) phosphorylation of both nonmuscle (NM) and smooth muscle (SM) myosins, which are determined by the activities of MLC kinase and MLC phosphatase. Further, NO mediated vasodilatation requires the expression of a leucine zipper positive (LZ+) isoform of the myosin targeting subunit (MYPT1) of MLC phosphatase.

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The present study investigated whether post-event processing (PEP) involving mental imagery about a past speech is particularly detrimental for socially anxious individuals who are currently anticipating giving a speech. One hundred fourteen high and low socially anxious participants were told they would give a 5 min impromptu speech at the end of the experimental session. They were randomly assigned to one of three manipulation conditions: post-event processing about a past speech incorporating imagery (PEP-Imagery), semantic post-event processing about a past speech (PEP-Semantic), or a control condition, (n=19 per experimental group, per condition [high vs low socially anxious]).

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