Stressed brain, diseased heart: a review on the pathophysiologic mechanisms of neurocardiology

Risk factors for late-onset generalized anxiety disorder: results from a 12-year prospective cohort (the ESPRIT study)

Generalized anxiety disorder (GAD) is a chronic and highly prevalent disorder associated with increased disability and mortality in the elderly. Treatment is difficult with low rate of full remission, thus highlighting the need to identify early predictors for prevention in elderly people. The aim of this study is to identify and characterize incident GAD predictors in elderly people. A total of 1711 individuals aged 65 years and above and free of GAD at baseline were randomly recruited from electoral rolls between 1999 and 2001 (the prospective ESPRIT study). The participants were examined at baseline and five times over 12 years. GAD and psychiatric comorbidity were diagnosed with a standardized psychiatric examination, the Mini-International Neuropsychiatry Interview on the basis of DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) criteria and validated by a clinical panel. During the follow-up, 8.4% (95% confidence interval=7.1-9.7%) of the participants experienced incident GAD, 80% being first episodes; the incident rate being 10 per 1000 person-years. The principal predictors of late-onset incident GAD over 12 years derived from a multivariate Cox model were being female, recent adverse life events, having chronic physical (respiratory disorders, arrhythmia and heart failure, dyslipidemia, cognitive impairment) and mental (depression, phobia and past GAD) health disorders. Poverty, parental loss or separation and low affective support during childhood, as well as history of mental problems in parents were also significantly and independently associated with incident GAD. GAD appears as a multifactorial stress-related affective disorder resulting from both proximal and distal risk factors, some of them being potentially modifiable by health care intervention.

Coronary Microvascular Function and Beyond: The Crosstalk between Hormones, Cytokines, and Neurotransmitters

Beyond its hemodynamic function, the heart also acts as a neuroendocrine and immunoregulatory organ. A dynamic communication between the heart and other organs takes place constantly to maintain cardiovascular homeostasis. The current understanding highlights the importance of the endocrine, immune, and nervous factors to fine-tune the crosstalk of the cardiovascular system with the entire body. Once disrupted, this complex interorgan communication may promote the onset and the progression of cardiovascular diseases. Thus, expanding our knowledge on how these factors influence the cardiovascular system can lead to novel therapeutic strategies to improve patient care. In the present paper, we review novel concepts on the role of endocrine, immune, and nervous factors in the modulation of microvascular coronary function.

Multimorbidity in a Mexican Community: Secondary Analysis of Chronic Illness and Depression Outcomes

The aims of this article are: 1) to examine the associations between health provider-diagnosed depression and multimorbidity, the condition of suffering from more than two chronic illnesses; 2) to assess the unique contribution of chronic illness in the prediction of depression; and 3) to suggest practice changes that would address risk of depression among individuals with chronic illnesses. Data collected in a cross-sectional community health study among adult Mexicans (n= 274) living in a low income neighborhood (colonia) in Ciudad Juárez, Chihuahua, Mexico, were examined. We tested the hypotheses that individuals who reported suffering chronic illnesses would also report higher rates of depression than healthy individuals; and having that two or more chronic illnesses further increased the risk of depression.

Investigating the role of acute mental stress on endothelial dysfunction: a systematic review and meta-analysis

Chronic stress is a known risk factor for both endothelial dysfunction and cardiovascular disease (CVD), but less is known of how acute mental stress affects the vasculature. In this systematic review and meta-analysis, we analyzed the impact of acute mental stress on flow-mediated dilation (FMD), an indicator of endothelial function. We searched the Medline, Cochrane, EMBASE, and ISI Web of Knowledge databases through May 2014, to identify publications in English-language journals. The primary outcome was the change in FMD from baseline to the time of measurement. We also assessed the risk of bias and the heterogeneity of included studies. Our search identified eight prospective studies, which displayed significant heterogeneity. Four studies measured FMD while the subject was performing the task; six measured FMD after the task had been completed. The total number of participants was 164. The pooled results indicate that FMD did not change significantly while the task was being performed (pooled difference in means: -0.853; 95 % confidence interval (CI), -3.926/2.220; P = 0.586); however, FMD measured after the task was completed was significantly less than baseline (pooled difference in means: -2.450; 95 %CI, -3.925/-0.975; P = 0.001). In conclusions, our findings provide evidence that an acute stressful experience has a delayed, negative impact on the function of the endothelium. Repeated exposure to short-term stress may lead to permanent injury of the vasculature. Therefore, assessment of patients' exposure to both repeated acute mental stress and chronic stress may be useful in determining their risk of developing CVD.

Correlation between Surgeon's experience, surgery complexity and the alteration of stress related physiological parameters

Introduction

In the present work we analyzed the hormonal (salivary Cortisol; sC), immune (salivary Immunoglobulin A; sIgA) and cardiovascular (Heart rate, HR, and systolic blood pressure, SBP) responses induced by stress conditions in oral surgeons, randomly recruited according to their expertise level.

Materials and methods

Each surgeon performed three different surgical procedures with increasing degrees of technical difficulty and under time-limited conditions, to assess whether these variants may influence the risks of stress-induced secondary hypertension among the involved health professionals. sC and sIgA samples and cardiovascular function measurements were taken up before, during, and two hours after every surgery. Salivary samples and cardiovascular measurements were taken also during non-surgical days, as baseline controls.

Results

We observed that more experienced surgeons showed a higher stress management ability compared to those with less experience or, generally, younger, which are more exposed to the risks of developing secondary hypertension. Nevertheless, indipendently of sex and experience, oral surgeons are constantly exposed to high risks of developing stress-related diseases.

Conclusions

On the basis of the issues addressed and the results obtained, we have highlighted the importance of the investigated stress biomarkers to monitor and to prevent stress-related pathologies among oral surgeons. This approach is aimed to emphasize the significance of these specific stress-biomarkers, which represent a powerful instrument to evaluate stress levels in oral surgeons, and that may help to reduce the most severe life-threatening risks to which they are daily exposed. In conclusion, final goal of this study is to suggest an useful guideline to monitor the stress levels of oral and maxillofacial surgeons in order to improve their quality of life, which is inevitably reflected on the quality of the performances provided and, finally, to prevent possible mistakes in their daily activities.

Dysfunction of the CNS-heart axis in mouse models of Huntington's disease

Cardiac remodelling and contractile dysfunction occur during both acute and chronic disease processes including the accumulation of insoluble aggregates of misfolded amyloid proteins that are typical features of Alzheimer's, Parkinson's and Huntington's disease (HD). While HD has been described mainly as a neurological disease, multiple epidemiological studies have shown that HD patients exhibit a high incidence of cardiovascular events leading to heart failure, and that this is the second highest cause of death. Given that huntingtin is ubiquitously expressed, cardiomyocytes may be at risk of an HD-related dysfunction. In mice, the forced expression of an expanded polyQ repeat under the control of a cardiac specific promoter led to severe heart failure followed by reduced lifespan. However the mechanism leading to cardiac dysfunction in the clinical and pre-clinical HD settings remains unknown. To unravel this mechanism, we employed the R6/2 transgenic and HdhQ150 knock-in mouse models of HD. We found that pre-symptomatic animals developed connexin-43 relocation and a significant deregulation of hypertrophic markers and Bdnf transcripts. In the symptomatic animals, pronounced functional changes were visualised by cardiac MRI revealing a contractile dysfunction, which might be a part of dilatated cardiomyopathy (DCM). This was accompanied by the re-expression of foetal genes, apoptotic cardiomyocyte loss and a moderate degree of interstitial fibrosis. To our surprise, we could identify neither mutant HTT aggregates in cardiac tissue nor a HD-specific transcriptional dysregulation, even at the end stage of disease. We postulate that the HD-related cardiomyopathy is caused by altered central autonomic pathways although the pathogenic effects of mutant HTT acting intrinsically in the heart may also be a contributing factor.

Huntington's disease (HD) is a neurodegenerative disorder for which the mutation results in an extra-long tract of glutamines that causes the huntingtin protein to aggregate. It is characterized by neurological symptoms and brain pathology that is associated with nuclear and cytoplasmic aggregates and with transcriptional dysregulation. Despite the fact that HD has been recognized principally as a neurological disease, there are multiple epidemiological studies showing that HD patients exhibit a high rate of cardiovascular events leading to heart failure. To unravel the cause of cardiac dysfunction in HD models, we employed a wide range of molecular and physiological methods using two well established genetic mouse models of this disease. We found that pre-symptomatic animals developed aberrant gap junction channel expression and a significant deregulation of hypertrophic markers that may predispose them to arrhythmia and an overall change in cardiac function. These changes were accompanied by the re-expression of foetal genes, apoptotic cardiomyocyte loss and a moderate degree of interstitial fibrosis in the symptomatic animals. Surprisingly, we could identify neither mutant HTT aggregates in cardiac tissue nor a HD-specific transcriptional dysregulation. Therefore, we conclude that the HD-related cardiomyopathy could be driven by altered central autonomic pathways.

Alterations in phospholipidomic profile in the brain of mouse model of depression induced by chronic unpredictable stress

Depression is a worldwide disability disease associated with high morbidity and has increased dramatically in the last few years. The differential diagnosis and the definition of an individualized therapy for depression are hampered by the absence of specific biomarkers. The aim of this study was to evaluate the phospholipidomic profile of the brain and myocardium in a mouse model of depression induced by chronic unpredictable stress (CUS). The lipidomic profile was evaluated by thin layer and liquid chromatography and mass spectrometry and lipid oxidation was estimated by FOX II assay. Antioxidant enzyme activity and the oxidized/reduced glutathione (GSH/GSSG) ratio were also evaluated. Results showed that chronic stress affects primarily the lipid profile of the brain, inducing an increase in lipid hydroperoxides, which was not detected in the myocardium. A significant decrease in phosphatidylinositol (PI) and in cardiolipin (CL) relative contents and also oxidation of CL and a significant increase of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were observed in the brain of mice after unpredictable chronic stress conditions. In the myocardium only an increase in PC content was observed. Nevertheless, both organs present a decreased GSH/GSSG ratio when compared to control groups, corroborating the occurrence of oxidative stress. The enzyme activities of catalase (CAT) and superoxide dismutase (SOD) were found to be decreased in the myocardium and increased in the brain, while glutathione reductase (GR) was decreased in the brain. Our results indicate that in a mouse model for studying depression induced by CUS, the modification of the expression of oxidative stress-related enzymes did not prevent lipid oxidation in organs, particularly in the brain. These observations suggest that depression has an impact on the brain lipidome and that further studies are needed to better understand lipids role in depression and to evaluate their potential as future biomarkers.

Effect of depression and sertraline treatment on cardiac function in female nonhuman primates

OBJECTIVE

Depression is a proposed risk factor for heart failure based largely on epidemiological data; few experimental data addressing this hypothesis are available.

METHODS

Depression was evaluated in relation to cardiac structural and functional phenotypes assessed by transthoracic echocardiography in 42 adult female cynomolgus monkeys that consumed a Western-like diet for 3 years. Half of the monkeys were treated with sertraline HCl for 18 months, and depressive behavior was assessed for 12 months before echocardiography.

RESULTS

Depressed monkeys (the 19/42 with depressive behavior rates above the mean rate) had higher heart rates (HRs; 171 [4.1[ versus 152 [6.1]) and smaller body surface area (0.13 [0.003] versus 0.15 [0.004]), left ventricular (LV) end-systolic dimension (0.75 [0.05] versus 0.89 [0.04]), LV systolic (0.76 [0.08] versus 1.2 [0.11]) and diastolic (2.4 [0.23] versus 3.4 [0.26]) volumes, and left atrial volumes (1.15 [0.14] versus 1.75 [0.12]; p values < .05). Doppler profiles of depressed monkeys indicated greater myocardial relaxation (higher e' and higher e'/a' ratio) and lower filling pressures (lower E/e') compared to nondepressed monkeys (p values < .05). Although sertraline treatment reduced HR (150 [5.8] versus 171 [4.8]) and modestly increased chamber dimensions (LV end-systolic dimension: 0.91 [0.05] versus 0.74 [0.03]; LV end-diastolic dimension, body surface area adjusted 1.69 [0.05] versus 1.47 [0.06]; p values < .05), it did not overtly affect systolic or diastolic function (p values > .10).

CONCLUSIONS

These data suggest that behavioral depression in female primates is accompanied by differences in cardiac function, although not in ways classically associated with subclinical heart failure. Selective serotonin reuptakes show promise in supporting heart function by reducing HR and perhaps improving LV filling; however, further investigation is needed.

The neural basis of optimism and pessimism

Our survival and wellness require a balance between optimism and pessimism. Undue pessimism makes life miserable; however, excessive optimism can lead to dangerously risky behaviors. A review and synthesis of the literature on the neurophysiology subserving these two worldviews suggests that optimism and pessimism are differentially associated with the two cerebral hemispheres. High self-esteem, a cheerful attitude that tends to look at the positive aspects of a given situation, as well as an optimistic belief in a bright future are associated with physiological activity in the left-hemisphere (LH). In contrast, a gloomy viewpoint, an inclination to focus on the negative part and exaggerate its significance, low self-esteem as well as a pessimistic view on what the future holds are interlinked with neurophysiological processes in the right-hemisphere (RH). This hemispheric asymmetry in mediating optimistic and pessimistic outlooks is rooted in several biological and functional differences between the two hemispheres. The RH mediation of a watchful and inhibitive mode weaves a sense of insecurity that generates and supports pessimistic thought patterns. Conversely, the LH mediation of an active mode and the positive feedback it receives through its motor dexterity breed a sense of confidence in one's ability to manage life's challenges, and optimism about the future.

Depression after myocardial infarction: TNF-α-induced alterations of the blood-brain barrier and its putative therapeutic implications

Patients experiencing an acute myocardial infarction (AMI) have a three times higher chance to develop depression. Vice versa, depressive symptoms increase the risk of cardiovascular events. The co-existence of both conditions is associated with substantially worse prognosis. Although the underlying mechanism of the interaction is largely unknown, inflammation is thought to be of pivotal importance. AMI-induced peripheral cytokines release may cause cerebral endothelial leakage and hence induces a neuroinflammatory reaction. The neuroinflammation may persist even long after the initial peripheral inflammation has subsided. Among those selected brain regions that are prone to blood-brain barrier dysfunction, the paraventricular nucleus of the hypothalamus (PVN), a major center for cardiovascular autonomic regulation, is indicated to play a mediating role. Optimal cardiovascular therapy improves cardiovascular prognosis without major effects on depression. By the same token, antidepressant therapy in cardiovascular disease is associated with modest improvement in depressive symptoms, however without improvement in cardiac outcome. The failure of current antidepressants and the growing number of patients suffering from both conditions legitimize the search for better antidepressive therapies, from patients as well as society perspectives. Though we appreciate the mutual character of the interaction between depression and AMI, the present review focuses on the side of AMI induced depression and discusses the role of inflammation, represented by the proinflammatory cytokine TNF-α, as potential underlying mechanism. It is conceivable that inhibition of the inflammatory response post-AMI, through targeted anti-inflammatory pharmacotherapeutical agents may prevent the development of depressive symptoms and ultimately may improve cardiovascular outcomes.