Pathophysiological role of cytokines in congestive heart failure

Persisting IL-18 levels after COVID-19 correlate with markers of cardiovascular inflammation reflecting potential risk of CVDs development

COVID-19 manifestation is associated with a strong immune system activation leading to inflammation and subsequently affecting the cardiovascular system. The objective of the study was to reveal possible interconnection between prolongated inflammation and the development or exacerbation of long-term cardiovascular complications after COVID-19. We investigated correlations between humoral and cellular immune system markers together with markers of cardiovascular inflammation/dysfunction during COVID-19 onset and subsequent recovery. We analyzed 22 hospitalized patients with severe COVID-19 within three timepoints (acute, 1 and 6 months after COVID-19) in order to track the impact of COVID-19 on the long-term decline of the cardiovascular system fitness and eventual development of CVDs. Among the cytokines dysregulated during COVID-19 changes, we showed significant correlations of IL-18 as a key driver of several pathophysiological changes with markers of cardiovascular inflammation/dysfunction. Our findings established novel immune-related markers, which can be used for the stratification of patients at high risk of CVDs for further therapy.

The Role of Exercise-based Cardiac Rehabilitation in Heart Failure

Exercise-based cardiac rehabilitation (EBCR) is a treatment modality for patients with heart failure (HF) that has withstood the test of time. It has continued to show benefits even in the current era of pharmacotherapeutics for HF. Participation in a multidisciplinary comprehensive EBCR programme reduces mortality and morbidity, has a multitude of physiological benefits, and improves cardiovascular risk factor control and quality of life. Despite this, historical barriers to enrolment and uptake remain. Strategies to overcome these, as well as alternative delivery methods of EBCR in HF patients, are emerging and include telerehabilitation, focus on special groups and emphasis on behavioural change. This review provides oversight on the modalities of exercise training in HF as well as their benefits and gives an overview of barriers to the utilisation of EBCR along with future progress in the field.

Heart Failure in Chronic Infectious and Inflammatory Conditions: Mechanistic Insights from Clinical Heterogeneity

PURPOSE OF REVIEW

The balance between inflammation and its resolution plays an important and increasingly appreciated role in heart failure (HF) pathogenesis. In humans, different chronic inflammatory conditions and immune-inflammatory responses to infection can lead to diverse HF manifestations. Reviewing the phenotypic and mechanistic diversity of these HF presentations offers useful clinical and scientific insights.

RECENT FINDINGS

HF risk is increased in patients with chronic inflammatory and autoimmune disorders and relates to disease severity. Inflammatory condition-specific HF manifestations exist and underlying pathophysiologic causes may differ across conditions. Although inflammatory disease-specific presentations of HF differ, chronic excess in inflammation and auto-inflammation relative to resolution of this inflammation is a common underlying contributor to HF. Further studies are needed to phenotypically refine inflammatory condition-specific HF pathophysiologies and prognoses, as well as potential targets for intervention.

A Comprehensive Outlook on Dilated Cardiomyopathy (DCM): State-Of-The-Art Developments with Special Emphasis on OMICS-Based Approaches

Dilated cardiomyopathy (DCM) remains an enigmatic cardiovascular disease (CVD) condition characterized by contractile dysfunction of the myocardium due to dilation of the ventricles. DCM is one of the major forms of CVD contributing to heart failure. Dilation of the left or both ventricles with systolic dysfunction, not explained by known causes, is a hallmark of DCM. Progression of DCM leads to heart failure. Genetic and various other factors greatly contribute to the development of DCM, but the etiology has still remained elusive in a large number of cases. A significant number of studies have been carried out to identify the genetic causes of DCM. These candidate-gene studies revealed that mutations in the genes of the fibrous, cytoskeletal, and sarcomeric proteins of cardiomyocytes result in the development of DCM. However, a significant proportion of DCM patients are idiopathic in nature. In this review, we holistically described the symptoms, causes (in adults and newborns), genetic basis, and mechanistic progression of DCM. Further, we also summarized the state-of-the-art diagnosis, available biomarkers, treatments, and ongoing clinical trials of potential drug regimens. DCM-mediated heart failure is on the rise worldwide including in India. The discovery of biomarkers with a better prognostic value is the need of the hour for better management of DCM-mediated heart failure patients. With the advent of next-generation omics-based technologies, it is now possible to probe systems-level alterations in DCM patients pertaining to the identification of novel proteomic and lipidomic biomarkers. Here, we also highlight the onset of a systems-level study in Indian DCM patients by applying state-of-the-art mass-spectrometry-based “clinical proteomics” and “clinical lipidomics”.

Expression of adipocytokines in heart fat depots depending on the degree of coronary artery atherosclerosis in patients with coronary artery disease

In coronary artery disease (CAD) the adipocytokine content in the heart fat depot is altered, but it has not been established whether these changes are associated with the degree of atherosclerotic damage to the coronary artery (CA). Were examined 84 patients with CAD, and according to the degree of atherosclerotic state based on the SYNTAX Score scale, were divided: 39 moderate (≤22 points), 20 severe (23–31 points) and 25 extremely severe (≥32 points). Biopsies of subcutaneous (SAT), epicardial (EAT) and perivascular adipose tissue (PVAT) were obtained during elective coronary artery bypass grafting (CABG). The expression of adipocytokine was determined using real-time PCR. The concentration of the studied adipocytokines in adipocyte culture medium was measured by ELISA. Statistical analysis was performed using logistic regression analysis. In the adipocytes of the cardiac depot of patients with CAD, an increase in the expression and secretion of leptin and IL-6 and a decrease in adiponectin, with a maximum manifestation in severe and extremely severe CA lesions, was observed. EAT adipocytes were characterized by minimal expression of the adiponectin gene maximal gene expression leptin and IL-6 compared to SAT and PVAT adipocytes.

The role of interleukin-10 family members in cardiovascular diseases

Interleukin (IL)-10 cytokine family members, including IL-10, IL-19, IL-20, IL-22, IL-24, IL-26 and the distantly related IL-28A, IL-28B, and IL-29, play critical roles in the regulation of inflammation. The occurrence and progression of cardiovascular diseases closely correlate with the regulation of inflammation, which may provide novel strategies for the treatment of cardiovascular diseases. In recent years, studies have focused on the association between the IL-10 cytokine family and the physiological and pathological progression of cardiovascular diseases. The aim of this review is to summarize relevant studies and clarify whether the IL-10 cytokine family contributes to the regulation of cardiovascular diseases.

Differential Associations of Chronic Inflammatory Diseases With Incident Heart Failure

OBJECTIVES

The purpose of this study was to compare the risks of incident heart failure (HF) among a variety of chronic inflammatory diseases (CIDs) and to determine whether risks varied by severity of inflammation within each CID.

BACKGROUND

Individuals with CIDs are at elevated risk for cardiovascular diseases, but data are limited regarding risk for HF.

METHODS

An electronic health records database from a large urban medical system was examined, comparing individuals with CIDs with frequency-matched controls without CIDs, all of whom were receiving regular outpatient care. Rates of incident HF were determined by using the Kaplan-Meier method and subsequently used multivariate-adjusted proportional hazards models to compare HF risks for each CID. Exploratory analyses determined HF risks by proxy measurement of CID severity.

RESULTS

Of 37,636 patients (n = 18,278 patients with CIDs; and n = 19,358 controls without CIDs) there were 960 incident HF cases over a median of 3.6 years. Risks for incident HF were significantly or borderline significantly elevated for patients with systemic sclerosis (hazard ratio [HR]: 7.26; 95% confidence interval [CI]: 5.72 to 9.21; p < 0.01), systemic lupus erythematosus (HR: 3.15; 95% CI: 2.41 to 4.11; p < 0.01), rheumatoid arthritis (HR: 1.39; 95% CI: 1.13 to 1.71; p < 0.01), and human immunodeficiency virus (HR: 1.28; 95% CI: 0.99 to 1.66; p = 0.06). There was no association between psoriasis or inflammatory bowel disease and incident HF, although patients with those CIDs with higher levels of C-reactive protein had higher risks for HF than controls.

CONCLUSIONS

Systemic sclerosis and systemic lupus erythematosus were associated with the highest risks of HF, followed by rheumatoid arthritis and HIV. Measurements of inflammation were associated with HF risk across different CIDs.

Gender-Dependent Alteration of Ca2+ and TNFα Signaling in db/db Mice, an Obesity-Linked Type 2 Diabetic Model

Cardiovascular complications are the primary death cause in type 2 diabetes, where inflammation can play a role. We, and others, have previously shown that, in diabetic cardiomyopathy, cardiac dysfunction is associated with Ca²⁺ mishandling. It is possible that diabetic cardiomyopathy differently affects men and women, as the latter present higher risk to develop heart failure and a higher plasmatic level of the pro-inflammatory cytokine, tumor necrosis factor alpha (TNFα), than men. However, the gender-dependent regulation of Ca²⁺ signaling in diabetes and its relationship with TNFα signaling are still unclear. Here, we analyzed TNFα signaling pathway and its role in Ca²⁺ signaling dysfunction in male and female rodent models of type 2 diabetes linked to obesity (db/db mice) using confocal microscopy in freshly isolated cardiomyocytes. TNFα increased [Ca²⁺]_i transient amplitude and accelerated its decay without affecting SR Ca²⁺ load or Ca²⁺ spark frequency in cells from control mice. All TNFα effects on Ca²⁺ handling were prevented by the inhibition of the ceramidase and the phospholipase A2 (PLA2). While the plasmatic level of TNFα was similar in male and female db/db mice, only male db/db hearts over-expressed both TNFα converting enzyme (TACE) and the protective TNFα receptors 2 (TNF-R2). TNFα receptor 1 (TNF-R1) expression, involved in negative inotropic response of TNFα, was unchanged in both male and female db/db mice compared to controls. We found that male db/db mice cardiomyocytes presented a decrease in [Ca²⁺]_i transient amplitude associated to a drop of sarcoplasmic reticulum Ca²⁺ load, not seen in female db/db mice. Interestingly, sustained incubation with TNFα did not restored Ca²⁺ signaling alteration observed in male db/db mice but still induces an increase in Ca²⁺ spark frequency as seen in control littermates. In cardiomyocytes from female db/db mice, TNFα had no visible effects on Ca²⁺ handling. In conclusion, our study shows that the alteration of Ca²⁺ signaling and TNFα, seen in db/db mice, is gender specific presenting an increase in TNFα cardio-protective pathway in male mice.

The effect of antidepressant medications in the management of heart failure on outcomes: mortality, cardiovascular function and depression - a systematic review

OBJECTIVE

Depression is associated with increased morbidity, mortality and hospital readmission in patients with heart failure (HF). This systematic review aimed to compile studies examining whether the use of antidepressants could improve outcome in patients with HF and concomitant depression.

METHODS

The electronic libraries Embase, OVID MEDLINE(R) and PsychInfo were used to search the following terms 'heart failure' AND 'anti-depressants'; 'heart failure' AND 'TCA' OR 'SSRI' OR 'SNRI'. The result of this database search was analysed to select papers that satisfied our inclusion criteria.

RESULTS

Of the 180 papers found in the original database search, only three met the inclusion criteria. A further two papers were added from hand-searching through the references. Three of these papers are randomised controlled trials (RCT); the other two, cohort studies. All studies show that antidepressants are well tolerated in this group. There was no significant difference in depressive symptoms between the test and placebo. The cardiac outcomes of patients with HF are not improved by the use of antidepressants relative to placebo.

CONCLUSIONS

Antidepressants are not associated with increased mortality rate as established in previous papers. However, there is inadequate evidence that the use of antidepressants effects significant improvement in depression or cardiac outcomes.

Depression and chronic heart failure in the elderly: an intriguing relationship

Chronic heart failure and depressive disorders have a high prevalence and incidence in the elderly. Several studies have shown how depression tends to exacerbate coexisting chronic heart failure and its clinical outcomes and vice versa, especially in the elderly. The negative synergism between chronic heart failure and depression in the elderly may be approached only taking into account the multifaceted pathophysiological characteristics underlying both these conditions, such as behavioural factors, neurohormonal activation, inflammatory mediators, hypercoagulability and vascular damage. Nevertheless, the pathophysiological link between these two conditions is not well established yet. Despite the high prevalence of depression in chronic heart failure elderly patients and its negative prognostic value, it is often unrecognized especially because of shared symptoms. So the screening of mood disorders, using reliable questionnaires, is recommended in elderly patients with chronic heart failure, even if cannot substitute a diagnostic interview by mental health professionals. In this setting, treatment of depression requires a multidisciplinary approach including: psychotherapy, antidepressants, exercise training and electroconvulsive therapy. Pharmacological therapy with selective serotonin reuptake inhibitors, despite conflicting results, improves quality of life but does not guarantee better outcomes. Exercise training is effective in improving quality of life and prognosis but at the same time cardiac rehabilitation services are vastly underutilized.

Effect of Monocyte-to-Lymphocyte Ratio on Heart Failure Characteristics and Hospitalizations in a Coronary Angiography Cohort

Inflammation is a shared mechanism in coronary artery disease (CAD) and subsequent heart failure (HF), and circulating monocyte and lymphocyte counts predict CAD severity and outcomes. We investigated whether the monocyte-to-lymphocyte ratio (MLR) correlates with biomarkers of HF and extent of CAD, as well as future HF hospitalizations in patients undergoing coronary angiography. Therefore, we studied 1754 patients undergoing coronary angiography for stable CAD, unstable angina, or myocardial infarction. MLR was determined at blood draw before angiography and related cross-sectionally to HF biomarkers (ejection fraction, N-terminal pro-B-type natriuretic peptide [NTproBNP] levels) and CAD severity, as well as longitudinally with risk of HF hospitalizations during follow-up. In the entire cohort, median (interquartile range) MLR was 0.32 (0.24 to 0.43). High MLR was defined as the upper quartile and significantly associated with nonstable CAD (unstable angina; odds ratio [OR] 1.13, 95% confidence interval 1.06 to 1.21] or myocardial infarction [OR 1.10, 1.04 to 1.16]), more severe CAD (OR 1.39, 1.15 to 1.68), poorer ejection fraction (OR 1.63, 1.29 to 2.05), and higher NTproBNP levels (β 0.78, 0.59 to 0.96), all p <0.001. The associations with nonstable CAD and NTproBNP remained highly significant after covariate adjustment. Over a mean follow-up of 1.3 years, 46 HF hospitalizations occurred. A high MLR was significantly and independently predictive of HF hospitalizations during follow-up (hazard ratio 2.1 [1.1 to 4.1], p = 0.039) after adjustment for covariates and addition of MLR to the basic model significantly improved reclassification. In conclusion, MLR is strongly related to HF markers and predicts HF hospitalizations during follow-up in patients with CAD.

Dietary Copper Restriction-Induced Changes in Myocardial Gene Expression and the Effect of Copper Repletion

Dietary copper (Cu) restriction leads to cardiac hypertrophy and failure in mice, and Cu repletion (CuR) reverses the hypertrophy and prevents the transition to heart failure. The present study was undertaken to determine changes in myocardial gene expression involved in Cu deficient (CuD) cardiomyopathy and its reversal by CuR. Analysis was performed on three groups of mice: 4-week-old CuD mice that exhibited signs of cardiac failure, their age-matched copper-adequate (CuA) controls, and the CuD mice that were re-fed adequate Cu for 2 weeks. Total RNA was isolated from hearts and subjected to cDNA microarray and real-time reverse transcription-polymerase chain reaction analysis. Dietary CuD caused a decrease in cardiac mRNA of β-MHC, L-type Ca2+ channel, K-dependent NCX, MMP-2, -8, and -13, NF-κB, and VEGF. The mRNA levels of ET-1, TGF-β, TNF-α, and procollagen-l-α1 and III-α1 were increased in the CuD cardiac tissue. Copper repletion resulted in cardiac mRNA levels of most of the genes examined returning to control levels, although the K-dependent NCX and MMP-2 values did not reach those of the CuA control. In addition, CuR caused an increase in β-MHC, L-type Ca2+channel, MMP-13 to levels surpassing those of CuA control, and a decrease in ET-1, and TNF-at mRNA levels. In summary, changes in gene expression of elements involved in contractility, Ca2+ cycling, and inflammation and fibrosis may account for the altered cardiac function found in CuD mice. The return to normal cardiac function by CuR may be a result of the favorable regression in gene expression of these critical components in myocardial tissue.

Decreased effectiveness of ischemic heart preconditioning in the state of chronic inflammation

There is growing evidence, that beneficial effects of ischemic heart preconditioning (IPC) may be lost or limited due to diabetes, hyperlipidemia, hypertension, atherosclerosis, heart failure and senility. It is plausible, that these conditions interfere with the biochemical pathways underlying the IPC response, but the detailed explanation is not clear. Pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), monocyte chemotactic protein-1 (MCP-1), histamine and many other agents used in a single dose before prolonged ischemia mimic IPC. However prolonged exposure to preconditioning mimetics leads to tolerance (tachyphylaxis). In the state of such tolerance ischemic preconditioning is no longer protective. Studies suggest that diabetes, hyperlipidemia, hypertension, atherosclerosis, heart failure and older age are accompanied by increased plasma levels of pro-inflammatory cytokines, MCP-1 and other inflammatory mediators. Therefore, we raised the hypothesis, that the reported lack of benefits of IPC in the listed states may be due to tolerance to IPC developed during prolonged exposure of the myocardium to preconditioning mimetics.

Changes in Depressive Symptoms and Mortality in Patients With Heart Failure: Effects of Cognitive-Affective and Somatic Symptoms

OBJECTIVES

Depression is an independent predictor of adverse outcomes in patients with heart failure (HF). However, the effect of changes in cognitive-affective and somatic symptoms on mortality of HF patients is not known. The purpose of this study was to examine whether changes in cognitive-affective and somatic depressive symptoms over time were associated with mortality in HF.

METHODS

In this secondary analysis of data from the Rural Education to Improve Outcomes in Heart Failure clinical trial, we analyzed data from 457 HF patients (39% female, mean [standard deviation] age = 65.6 [12.8] years) who survived at least 1 year and repeated the Patient Health Questionnaire at 1 year. Cognitive-affective and somatic depression scores were calculated, respectively, based on published Patient Health Questionnaire factor models. Using Cox proportional hazards regression analyses, we evaluated the effect of changes in cognitive-affective and somatic symptoms from baseline to 1 year on cardiac and all-cause deaths.

RESULTS

Controlling for baseline depression scores and other patient characteristics, the change in somatic symptoms was associated with increased risk of cardiac death during the subsequent 1-year period (hazard ratio = 1.24, 95% confidence interval = 1.07-1.44, p = .005), but the change in cognitive-affective symptoms was not (hazard ratio = 0.94, 95% confidence interval = 0.81-1.08, p = .38). Similar results were found for all-cause mortality.

CONCLUSIONS

Worsening somatic depressive symptoms, not cognitive-affective symptoms, are independently associated with increased mortality of HF patients. The findings suggest that routine and ongoing assessment of somatic depressive symptoms in HF patients may help clinicians identify patients at increased risk for adverse outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00415545.

Mechanisms of Cardiotoxicity and the Development of Heart Failure

Cardiotoxicity is a broad term that refers to the negative effects of toxic substances on the heart. Cancer drugs can cause cardiotoxicity by effects on heart cells, thromboembolic events, and/or hypertension that can lead to heart failure. Rheumatoid arthritis biologics may interfere with ischemic preconditioning and cause/worsen heart failure. Long-term and heavy alcohol use can result in oxidative stress, apoptosis, and decreased contractile protein function. Cocaine use results in sympathetic nervous system stimulation of heart and smooth muscle cells and leads to cardiotoxicity and evolution of heart failure. The definition of cardiotoxicity is likely to evolve along with knowledge about detecting subclinical myocardial injury.

Psoriasis and risk of heart failure: a nationwide cohort study

AIMS

Psoriasis is a common inflammatory disease that is associated with increased risk of cardiovascular disease, including myocardial infarction. Heart failure (HF) is independently associated with several cardiovascular risk factors and is a major cause of cardiovascular morbidity and mortality. The association between psoriasis and HF is unclear and we therefore investigated the risk of new-onset HF in a nationwide cohort of psoriasis patients compared with the background population.

METHODS

The study included the entire Danish population aged ≥18 years followed from 1 January 1997 until HF, death or 31 December 2011. Information on comorbidity and concomitant medication was identified by individual-level linkage of administrative registers. New-onset HF was defined as first hospital admission for HF. Incidence rates of new-onset HF were calculated and adjusted hazard ratios were estimated by multivariable Cox regression models adjusted for age, gender, comorbidity and cardiovascular medications.

RESULTS

A total of 5 485 856 subjects were eligible for analysis. In the study period 66 389 patients with new-onset psoriasis, including 11 242 patients with severe psoriasis, were identified. The overall incidence rates of new-onset HF were 2.82, 4.22 and 4.70 per 1000 person-years for the reference population, mild psoriasis and severe psoriasis, respectively. Compared with the reference population, the fully adjusted hazard ratios for new-onset HF were increased in patients with psoriasis with a hazard ratio 1.22 (95% confidence interval 1.16-1.29) and hazard ratio of 1.53 (95% confidence interval 1.34-1.74) for those with mild and severe disease, respectively.

CONCLUSION

In this nationwide cohort, psoriasis was associated with a disease severity-dependent increased risk of new-onset HF.

Endoplasmic reticulum stress and Nox-mediated reactive oxygen species signaling in the peripheral vasculature: potential role in hypertension

SIGNIFICANCE

Reactive oxygen species (ROS) are produced during normal endoplasmic reticulum (ER) metabolism. There is accumulating evidence showing that under stress conditions such as ER stress, ROS production is increased via enzymes of the NADPH oxidase (Nox) family, especially via the Nox2 and Nox4 isoforms, which are involved in the regulation of blood pressure. Hypertension is a major contributor to cardiovascular and renal disease, and it has a complex pathophysiology involving the heart, kidney, brain, vessels, and immune system. ER stress activates the unfolded protein response (UPR) signaling pathway that has prosurvival and proapoptotic components.

RECENT ADVANCES

Here, we summarize the evidence regarding the association of Nox enzymes and ER stress, and its potential contribution in the setting of hypertension, including the role of other conditions that can lead to hypertension (e.g., insulin resistance and diabetes).

CRITICAL ISSUES

A better understanding of this association is currently of great interest, as it will provide further insights into the cellular mechanisms that can drive the ER stress-induced adaptive versus maladaptive pathways linked to hypertension and other cardiovascular conditions. More needs to be learnt about the precise signaling regulation of Nox(es) and ER stress in the cardiovascular system.

FUTURE DIRECTIONS

The development of specific approaches that target individual Nox isoforms and the UPR signaling pathway may be important for the achievement of therapeutic efficacy in hypertension.

Benazepril inhibited the NF-κB and TGF-β networking on LV hypertrophy in rats

PURPOSE

Benazepril, an angiotensin-converting enzyme (ACE) inhibitor, has been used to treat hypertension, congestive heart failure, and chronic renal failure. However, its biological activity and mechanism of action in inflammation are not fully identified. The present study was designed to determine the in vivo anti-inflammatory effects of benazepril on LV hypertrophy in rats.

METHODS

LV hypertrophy was produced in rats by abdominal aortic coarctation. They were then divided into the following groups: sham operation; LV hypertrophy; LV hypertrophy+benazepril (1mg/kg in a gavage, once a day for 4 weeks). Both morphological assays (hemodynamic and hemorheological measurement; LV hypertrophy assessment), and molecular assays (protein levels of Collagen type I/III, TNF-α and VCAM-1; TGF-β gene expression; NF-κB or Smad activation; intracellular ROS production) were performed.

RESULTS

The following effects were observed in rats treated with benazepril: (1) marked improvements in hemodynamic and hemorheological parameters; (2) significant reductions in LV hypertrophy, dilatation and fibrosis; (3) significantly attenuated protein levels of Collagen type I/III, TGF-β, TNF-α and VCAM-1, NF-κB or Smad activation, as well as intracellular ROS production.

CONCLUSIONS

These results suggest that the anti-inflammatory properties of benazepril may be ascribed to their down-regulation of both NF-κB and TGF-β signaling pathways by acting on the intracellular ROS production in rats with LV hypertrophy, thus supporting the use of benazepril as an anti-inflammatory agent.

Interleukin-10 activates Toll-like receptor 4 and requires MyD88 for cardiomyocyte survival

Toll-like receptors (TLRs) are important in a variety of inflammatory diseases including acute cardiac disorders. TLR4 innate signaling regulates the synthesis of anti-inflammatory cytokine, interleukin-10 (IL-10) upon TLR4 agonists' re-stimulation. Anti-apoptotic action of IL-10 in cardiac dysfunction is generally accepted but its protective mechanism through TLR4 is not yet understood. We studied the effect of IL-10 in the activation of TLR4 downstream signals leading to cardiomyocytes survival. IL-10 caused a significant increase in the expression of CD14, MyD88 and TLR4. TLR4 activation led to the translocation of the interferon regulatory factor 3 (IRF3) into the nucleus. Phosphorylation of IRF3 enhanced mRNA synthesis for IL-1β but not TNF-α and was elevated even after removal of IL-10 stimulation. Furthermore, degradation of inhibitory kappa B (IκB) kinase (Ikk) suggested that IκBβ was the main activating kinase for IRF3-regulated NF-κB activation and phosphorylation of p65. Phosphorylated NF-κB p65 was translocated into the nucleus. Concomitantly, an increase in Bcl-xL activity inhibited Bax and the proteolytic activity of caspase 3 as well as a decrease in PARP cleavage. An inhibition of MyD88, modulated the above listed responses to IL-10 as there was a decrease in TLR4 and IRF3 and an increase in TNF-α mRNA. This was associated with a decrease in NF-κB p65, Bcl-xL mRNA and protein levels as well as there was an activation of Bax and PARP cleavage independent of caspase 3 activation. These data in cardiomyocytes suggest that IL-10 induced anti-apoptotic signaling involves upregulation of TLR4 through MyD88 activation.

Increased soluble interleukin-2 receptor levels are related to somatic but not to cognitive-affective features in major depression

Cell-mediated immune activation may play a role in the pathogenesis of depression as indicated by findings of increased soluble tumor necrosis factor receptor (sTNF-R) levels and meta-analytic evidence for elevated soluble interleukin-2 receptor (sIL-2R) concentrations. However, little research has been done on how these soluble cytokine receptors are differently related to specific features in patients with depression. We measured levels of the soluble cytokine receptors sIL-2R, sTNF-R1 and sTNF-R2 in 25 non-medicated patients with major depression (DSM-IV) and 22 healthy controls. Psychometric measures included cognitive-affective depressive symptoms, somatoform symptoms, somatic and cognitive dimensions of anxiety and current mood states. While patients with depression showed increased levels of sIL-2R (p<0.01), differences in sTNF-R1 (p=0.09) and sTNF-R2 (p=0.08) marginally failed to reach significance. Increased concentrations of sIL-2R were related to somatic measures such as the severity of somatoform symptoms and somatic anxiety symptoms but not to cognitive-affective measures or current mood states. Our findings may suggest some specificity in the relationship between sIL-2R and symptom dimensions and highlight potential pathways by which T cell mediated immune activation may underpin somatic symptoms in depression.

Muscle oxygen transport and utilization in heart failure: implications for exercise (in)tolerance

The defining characteristic of chronic heart failure (CHF) is an exercise intolerance that is inextricably linked to structural and functional aberrations in the O(2) transport pathway. CHF reduces muscle O(2) supply while simultaneously increasing O(2) demands. CHF severity varies from moderate to severe and is assessed commonly in terms of the maximum O(2) uptake, which relates closely to patient morbidity and mortality in CHF and forms the basis for Weber and colleagues' (167) classifications of heart failure, speed of the O(2) uptake kinetics following exercise onset and during recovery, and the capacity to perform submaximal exercise. As the heart fails, cardiovascular regulation shifts from controlling cardiac output as a means for supplying the oxidative energetic needs of exercising skeletal muscle and other organs to preventing catastrophic swings in blood pressure. This shift is mediated by a complex array of events that include altered reflex and humoral control of the circulation, required to prevent the skeletal muscle "sleeping giant" from outstripping the pathologically limited cardiac output and secondarily impacts lung (and respiratory muscle), vascular, and locomotory muscle function. Recently, interest has also focused on the dysregulation of inflammatory mediators including tumor necrosis factor-α and interleukin-1β as well as reactive oxygen species as mediators of systemic and muscle dysfunction. This brief review focuses on skeletal muscle to address the mechanistic bases for the reduced maximum O(2) uptake, slowed O(2) uptake kinetics, and exercise intolerance in CHF. Experimental evidence in humans and animal models of CHF unveils the microvascular cause(s) and consequences of the O(2) supply (decreased)/O(2) demand (increased) imbalance emblematic of CHF. Therapeutic strategies to improve muscle microvascular and oxidative function (e.g., exercise training and anti-inflammatory, antioxidant strategies, in particular) and hence patient exercise tolerance and quality of life are presented within their appropriate context of the O(2) transport pathway.

Short-term magnesium deficiency upregulates ceramide synthase in cardiovascular tissues and cells: cross-talk among cytokines, Mg2+, NF-κB, and de novo ceramide

The present study tested the hypotheses that 1) short-term dietary deficiency (MgD) of magnesium (21 days) would result in the upregulation of ceramide synthase (CS) in left ventricular (LV), right ventricular, atrial, and aortic smooth muscle, as well as induce a synthesis/release of select cytokines and chemokines into the LV and aortic smooth muscle and serum; 2) exposure of primary cultured vascular smooth muscle cells (VSMCs) to low extracellular Mg concentration would lead to the synthesis/release of select cytokines/chemokines, activation of N-SMase, and the de novo synthesis of ceramide; and 3) inhibition of CS by fumonisin B1 (FB1) or inhibition of neutral sphingomyelinase (N-SMase) by scyphostatin (SCY) in VSMCs exposed to low Mg would result in reductions in the levels of the cytokines/chemokines and lowered levels of ceramide concomitant with inhibition of NF-κB activation. The data indicated that short-term MgD (10% normal dietary intake) resulted in the upregulation of CS in ventricular, atrial, and aortic smooth muscles coupled to the synthesis/release of 12 different cytokines/chemokines, as well as activation of NF-κB in the LV and aortic smooth muscle and sera; even very low levels of water-borne Mg (e.g., 15 mg·l−1·day−1) either prevented or ameliorated the upregulation and synthesis of the cytokines/chemokines. Our experiments also showed that VSMCs exposed to low extracellular Mg resulted in the synthesis of 5 different cytokines and chemokines concomitant with synthesis/release of ceramide. However, inhibition of the synthesis and release of ceramide by either FB1 or SCY attenuated, markedly , the generation of ceramide, release of the cytokines/chemokines, and activation of NF-κB (as measured by activated p65 and cRel).

A topographical map of the causal network of mechanisms underlying the relationship between major depressive disorder and coronary heart disease

OBJECTIVE

Major depressive disorder (MDD) and coronary heart disease (CHD) are both clinically important public health problems. Depression is linked with a higher incidence of ischaemic cardiac events and MDD is more prevalent in patients with CHD. No single comprehensive model has yet described the causal mechanisms linking MDD to CHD. Several key mechanisms have been put forward, comprising behavioural mechanisms, genetic mechanisms, dysregulation of immune mechanisms, coagulation abnormalities and vascular endothelial dysfunction, polyunsaturated omega-3 free fatty acid deficiency, and autonomic mechanisms. It has been suggested that these mechanisms form a network, which links MDD and CHD. The aim of this review is to examine the causal mechanisms underlying the relationship between MDD and CHD, with the aim of constructing a topological map of the causal network which describes the relationship between MDD and CHD.

METHODS

The search term 'depression and heart disease' was entered into an electronic multiple database search engine. Abstracts were screened for relevance and individually selected articles were collated.

RESULTS

This review introduces the first topological map of the causal network which describes the relationship between MDD and CHD.

CONCLUSIONS

Viewing the causal pathways as an interdependent network presents a new paradigm in this field and provides fertile ground for further research. The causal network can be studied using the methodology of systems biology, which is briefly introduced. Future research should focus on the creation of a more comprehensive topological map of the causal network and the quantification of the activity between each node of the causal network.

Depression in heart failure: biobehavioral mechanisms

The etiology, predictive value, and biobehavioral aspects of depression in heart failure (HF) are described in this article. Clinically elevated levels of depressive symptoms are present in approximately 1 out of 5 patients with HF. Depression is associated with poor quality of life and a greater than 2-fold risk of clinical HF progression and mortality. The biobehavioral mechanisms accounting for these adverse outcomes include biological processes (elevated neurohormones, autonomic nervous system dysregulation, and inflammation) and adverse health behaviors (physical inactivity, medication nonadherence, poor dietary control, and smoking). Depression often remains undetected because of its partial overlap with HF-related symptoms and lack of systematic screening. Behavioral and pharmacologic antidepressive interventions commonly result in statistically significant but clinically modest improvements in depression and quality of life in HF, but not consistently better clinical HF or cardiovascular disease outcomes. Documentation of the biobehavioral pathways by which depression affects HF progression will be important to identify potential targets for novel integrative behavioral and pharmacologic interventions.

PARM-1 is an endoplasmic reticulum molecule involved in endoplasmic reticulum stress-induced apoptosis in rat cardiac myocytes

To identify novel transmembrane and secretory molecules expressed in cardiac myocytes, signal sequence trap screening was performed in rat neonatal cardiac myocytes. One of the molecules identified was a transmembrane protein, prostatic androgen repressed message-1 (PARM-1). While PARM-1 has been identified as a gene induced in prostate in response to castration, its function is largely unknown. Our expression analysis revealed that PARM-1 was specifically expressed in hearts and skeletal muscles, and in the heart, cardiac myocytes, but not non-myocytes expressed PARM-1. Immunofluorescent staining showed that PARM-1 was predominantly localized in endoplasmic reticulum (ER). In Dahl salt-sensitive rats, high-salt diet resulted in hypertension, cardiac hypertrophy and subsequent heart failure, and significantly stimulated PARM-1 expression in the hearts, with a concomitant increase in ER stress markers such as GRP78 and CHOP. In cultured cardiac myocytes, PARM-1 expression was stimulated by proinflammatory cytokines, but not by hypertrophic stimuli. A marked increase in PARM-1 expression was observed in response to ER stress inducers such as thapsigargin and tunicamycin, which also induced apoptotic cell death. Silencing PARM-1 expression by siRNAs enhanced apoptotic response in cardiac myocytes to ER stresses. PARM-1 silencing also repressed expression of PERK and ATF6, and augmented expression of CHOP without affecting IRE-1 expression and JNK and Caspase-12 activation. Thus, PARM-1 expression is induced by ER stress, which plays a protective role in cardiac myocytes through regulating PERK, ATF6 and CHOP expression. These results suggested that PARM-1 is a novel ER transmembrane molecule involved in cardiac remodeling in hypertensive heart disease.

Effects of CXCR4 gene transfer on cardiac function after ischemia-reperfusion injury

Acute coronary occlusion is the leading cause of death in the Western world. There is an unmet need for the development of treatments to limit the extent of myocardial infarction (MI) during the acute phase of occlusion. Recently, investigators have focused on the use of a chemokine, CXCL12, the only identified ligand for CXCR4, as a new therapeutic modality to recruit stem cells to individuals suffering from MI. Here, we examined the effects of overexpression of CXCR4 by gene transfer on MI. Adenoviruses carrying the CXCR4 gene were injected into the rat heart one week before ligation of the left anterior descending coronary artery followed by 24 hours reperfusion. Cardiac function was assessed by echocardiography couple with 2,3,5-Triphenyltetrazolium chloride staining to measure MI size. In comparison with control groups, rats receiving Ad-CXCR4 displayed an increase in infarct area (13.5% +/- 4.1%) and decreased fractional shortening (38% +/- 5%). Histological analysis revealed a significant increase in CXCL12 and tumor necrosis factor-alpha expression in ischemic area of CXCR4 overexpressed hearts. CXCR4 overexpression was associated with increased influx of inflammatory cells and enhanced cardiomyocyte apoptosis in the infarcted heart. These data suggest that in our model overexpressing CXCR4 appears to enhance ischemia/reperfusion injury possibly due to enhanced recruitment of inflammatory cells, increased tumor necrosis factor-alpha production, and activation of cell death/apoptotic pathways.

Reduction and activation of circulating dendritic cells in patients with decompensated heart failure

BACKGROUND

Dendritic cells (DCs) are the most potent antigen-presenting cells and play a central role in initiating the primary immune response. Although increasing evidence supports immune-mediated inflammation plays an important role in the pathophysiology of heart failure, little is known regarding the source and mechanism that trigger immune responses. The present study examined whether circulating DCs have any role in the pathophysiology in heart failure in humans.

METHODS AND RESULTS

With multi-color flow cytometry we determined the numbers of circulating myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) in decompensated heart failure patients with NYHA class III or IV on admission (n = 27) and the age-similar control subjects (n = 21). DC activation markers such as CD40, and CCR7 were also measured. On admission, circulating mDC and pDC counts were significantly lower in decompensated heart failure patients compared to control subjects (p < 0.01). Circulating mDCs and pDCs were activated in the decompensated heart failure patients. Heart failure treatment restored the reduction and the activation of circulating mDCs and pDCs (p < 0.05). The increases of circulating DCs numbers after treatment were correlated with the decreases in B-type natriuretic peptide (BNP) and troponin-T (p < 0.05) and with the increase in left ventricular ejection fraction (LVEF) (p < 0.01). Furthermore, we found that poor recovery of the circulating DCs number after treatment predicted recurrence of decompensated heart failure.

CONCLUSION

These findings suggest that the reduction and activation of circulating DCs may be involved in the pathophysiology of heart failure.

Oxysterols in heart failure

Oxysterols are biologically active molecules that result from the oxidation of cholesterol. Several oxysterols are found in macrophages and macrophage-derived 'foam cells' in atherosclerotic tissue. Lipophilic oxysterols penetrate cell membranes and, therefore, their concentrations can reach harmful levels in endothelial and smooth muscle cells located in close proximity to the atherosclerotic plaques or inflammatory zones. New findings suggest that the effects of oxysterols on cardiomyocytes can lead to cell hypertrophy and death. This may make oxysterols one of the major factors precipitating morbidity in atherosclerosis-induced cardiac diseases and inflammation-induced heart complications. The pathological actions of oxysterols on muscle cells were shown to depend on dysfunctional Ca(2+) signaling; however, the mechanisms of the effects remain to be elucidated. Understanding the effects of oxysterols could lead to therapies that modulate malfunction of cardiomyocytes. This review discusses the experimental findings and the relevance of oxysterols to heart failure, and suggests strategies for important future investigations.

Effects of methotrexate on plasma cytokines and cardiac remodeling and function in postmyocarditis rats

Excessive immune activation and inflammatory mediators may play a critical role in the pathogenesis of chronic heart failure. Methotrexate is a commonly used anti-inflammatory and immunosuppressive drug. In this study, we used a rat model of cardiac myosin-induced experimental autoimmune myocarditis to investigate the effects of low-dose methotrexate (0.1 mg/kg/d for 30 d) on the plasma level of cytokines and cardiac remodeling and function. Our study showed that levels of tumor necrosis factor-(TNF-)alpha and interleukin-6 (IL-6) are significantly increased in postmyocarditis rats, compared with the control rats. Methotrexate treatment reduced the plasma levels of TNF-alpha and IL-6 and increased IL-10 level, compared to saline treatment. In addition, postmyocarditis rats showed significant cardiac fibrosis characterized by increased myocardial collagen volume fraction, perivascular collagen area, and the ratio of collagen type I to type III, compared with the control rats. However, MTX treatment not only markedly attenuated cardiac fibrosis, diminished the left ventricular end-diastolic dimension, but also increased the left ventricular ejection fraction and fractional shortening. Collectively, these results suggest that low-dose methotrexate has ability to regulate inflammatory responses and improves cardiac function and hence contributes to prevent the development of postmyocarditis dilated cardiomyopathy.

Mechanisms by which exercise training benefits patients with heart failure

Clinical consequences of heart failure are fatigue, dyspnea, and progressive impairment of exercise tolerance. Regular exercise training is associated with health-improving effects. In patients with stable heart failure, exercise training can relieve symptoms, improve exercise capacity and quality of life, as well as reduce hospitalization and, to some extent, risk of mortality. Progressive exercise training is associated with pulmonary, cardiovascular, and skeletal muscle metabolic adaptations that increase oxygen delivery and energy production. This Review focuses on current knowledge of mechanisms by which progressive and moderate exercise training can have sustained beneficial effects on patients with heart failure.

Epicardial adipose tissue as a source of nuclear factor-kappaB and c-Jun N-terminal kinase mediated inflammation in patients with coronary artery disease

CONTEXT

Visceral adipose tissue (AT) is known to confer a significantly higher risk of type 2 diabetes and cardiovascular disease. Epicardial AT has been shown to be related to cardiovascular disease and myocardial function through unidentified mechanisms. Epicardial AT expresses an inflammatory profile of proteins; however, the mechanisms responsible are yet to be elucidated.

OBJECTIVES

The objectives of the study were to: 1) examine key mediators of the nuclear factor-kappaB (NFkappaB) and c-Jun N-terminal kinase (JNK) pathways in paired epicardial and gluteofemoral (thigh) AT from coronary artery disease (CAD) and control patients and 2) investigate circulating endotoxin levels in CAD and control subjects.

DESIGN

Serums and AT biopsies (epicardial and thigh) were obtained from CAD (n = 16) and non-CAD (n = 18) patients. Inflammation was assessed in tissue and serum samples through Western blot, real-time PCR, ELISAs, and activity studies.

RESULTS

Western blotting showed epicardial AT had significantly higher NFkappaB, inhibitory-kappaB kinase (IKK)-gamma, IKKbeta, and JNK-1 and -2 compared with thigh AT. Epicardial mRNA data showed strong correlations between CD-68 and toll-like receptor-2, toll-like receptor-4, and TNF-alpha. Circulating endotoxin was elevated in patients with CAD compared with matched controls [CAD: 6.80 +/- 0.28 endotoxin unit(EU)/ml vs. controls: 5.52 +/- 0.57 EU/ml; P<0.05].

CONCLUSION

Epicardial AT from patients with CAD shows increased NFkappaB, IKKbeta, and JNK expression compared with both CAD thigh AT and non-CAD epicardial AT, suggesting a depot-specific as well as a disease-linked response to inflammation. These studies implicate both NFkappaB and JNK pathways in the inflammatory profile of epicardial AT and highlight the role of the macrophage in the inflammation within this tissue.

Leptin modulates the negative inotropic effect of interleukin-1beta in cardiac myocytes

Interleukin-1beta (IL-1beta) is a potent negative inotrope implicated in the functional abnormalities of heart failure. Because the adipokine, leptin, protects against some of the cardiovascular effects of endotoxin, we hypothesized that leptin may modulate the cardiosuppressive effects of IL-1beta in isolated cardiomyocytes. Ventricular cardiac myocytes isolated from adult male Sprague Dawley rats were analyzed simultaneously for electrically stimulated contractility and calcium transients following 30 min exposure to IL-1beta (10 ng/ml) with or without 60 min pretreatment with leptin (25 ng/ml). IL-1beta decreased cell shortening, depressed maximal velocities of shortening and relengthening, and prolonged the time to 90% relaxation. The change in fura2-AM fluorescence ratio amplitude (Delta[Ca(2+)]) was significantly depressed and the time to return to baseline [Ca(2+)] was prolonged. The negative inotropic effects of IL-1beta were blocked by the neutral sphingomyelinase inhibitor Manumycin A (5 microM) or the ceramidase inhibitor N-oleoyl ethanolamine (1 microM). Prior exposure of myocytes to leptin blocked IL-1beta-induced cardiosuppression in conjunction with a blunting of IL-1beta stimulated ceramide accumulation. These data suggest that leptin may modulate IL-1beta signaling through the sphingolipid signaling pathway in cardiomyocytes.

Blockade of NF-kappaB using IkappaB alpha dominant-negative mice ameliorates cardiac hypertrophy in myotrophin-overexpressed transgenic mice

Nuclear factor-kappaB (NF-kappaB) is a ubiquitous transcription factor that regulates various kinds of genes including inflammatory molecules, macrophage infiltration factors, cell adhesion molecules, and so forth, in various disease processes including cardiac hypertrophy and heart failure. Previously, we have demonstrated that activation of NF-kappaB was required in myotrophin-induced cardiac hypertrophy, in spontaneously hypertensive rats, and in dilated cardiomyopathy human hearts. Moreover, our recent study using the myotrophin-overexpressed transgenic mouse (Myo-Tg) model showed that short hairpin RNA-mediated knockdown of NF-kappaB significantly attenuated cardiac mass associated with improved cardiac function. Although it has been shown that NF-kappaB is substantially involved in cardiovascular remodeling, it is not clear whether the continuous blockade of NF-kappaB is effective in cardiovascular remodeling. To address this question, we took a genetic approach using IkappaB alpha triple mutant mice (3M) bred with Myo-Tg mice (a progressive hypertrophy/heart failure model). The double transgenic mice (Myo-3M) displayed an attenuated cardiac hypertrophy (9.8+/-0.62 versus 5.4+/-0.34, p<0.001) and improved cardiac function associated with significant inhibition of the NF-kappaB signaling cascade, hypertrophy marker gene expression, and inflammatory and macrophage gene expression at 24 weeks of age compared to Myo-Tg mice. NF-kappaB-targeted gene array profiling displayed several important genes that were significantly downregulated in Myo-3M mice compared to Myo-Tg mice. Furthermore, Myo-3M did not show any changes of apoptotic gene expression, indicating that significant inhibition of NF-kappaB activation reduces further proinflammatory reactions without affecting susceptibility to apoptosis. Therefore, development of therapeutic strategies targeting NF-kappaB may provide an effective approach to prevent adverse cardiac pathophysiological consequences.

High impact of depression in heart failure: Early diagnosis and treatment options

Depressive syndromes in chronic heart failure (CHF) are common and are associated with a poorer prognosis, particularly with increased morbidity and mortality. CHF as a severe physical disorder may increase the risk of developing depressive syndromes or vice-versa as an interaction of possible common psycho-organic etiological aspects. Depression in CHF is associated with impaired NYHA status and daily activities, resulting in enhanced hospitalisation rates and medical costs with a great impact on long-term health. Only a fraction of comorbid patients receives antidepressants. Therefore, identification of risk factors and prevention by optimizing cardiological and psychiatric therapeutic strategies appear essential for these patients. Early diagnosis and treatment of both CHF and depression may prevent further pathophysiological effects on the heart and brain. This review gives a comprehensive overview of the occurrence, risk factors and shared pathophysiology of depression in CHF, and focuses on improving insufficient diagnosis and therapy of depression. Special attention is given on the cardiac effects of psychopharmacological and alternate non-pharmacological antidepressant therapy in CHF. Recommendations are made for treating depression in CHF patients for a better prevention of this disabling physical and psychosocial condition.

Pathogenesis of chronic heart failure: change of dominating paradigm

The review considers literature data reflecting the evolution of views on pathogenesis of chronic heart failure. Connection of revision of a dominating paradigm of pathogenesis at every stage of development of cardiology with changes in approaches to therapy of chronic heart failure is analyzed.

Effects of interleukin-2 on the mechanical restitution and post-rest contraction in rat ventricular papillary muscle

To determine whether application of interleukin-2 (IL-2) alters function of sarcoplasmic reticulum (SR), we measured mechanical restitution and post-rest potentiation (PRP) in isolated rat papillary muscles. Mechanical restitution curves were constructed by interpolating extrasystoles at different test intervals following a train of steady state beats. In control group, the maximal PRP was reached after 60-120s of rest and the maximal potentiation factor was 2.36 +/- 0.23. IL-2 at 200 U/ml decreased the steady-state force of contraction to 56.4 +/- 7.2% of pre-drug control. But the time constant of recovery of steady-state force was not altered after IL-2. IL-2 decreased PRP at all intervals, shifted the potentiation curve parallel to lower values. But the potentiation was enhanced when compared with pre-rest control value in the presence of IL-2. In papillary muscle treated with IL-2, the onset of maximal PRP was delayed and the potentiation factor after 300s was 4.72 +/- 0.58 times that at the steady-state. Recirculation fraction of calcium calculated from the decay of PRP was 0.78 +/- 0.09 in control and 0.59 +/- 0.08 after IL-2 treatment. We conclude that IL-2 decreases the function of SR, which suggests that an impaired function of SR may contribute to the negative inotropic effect of IL-2.

Immune Modulation Therapy in Heart Failure

Several lines of evidence suggest that inflammation plays a pathogenic role in the development and progression of congestive heart failure, influencing heart contractility and hypertrophy, promoting apoptosis, and contributing to the myocardial remodeling process. As the prevalence of heart failure continues to increase, novel therapeutic strategies are employed to decrease the burden of this disease. Although multiple studies have suggested a potential for immunomodulatory therapy in heart failure patients, the precise role of this targeted approach still remains to be determined. Further research is needed to identify the key factors in the immunopathogenesis of heart failure, identify the patients who are most likely to respond, and develop management strategies that result in consistent benefit leading to decreased morbidity and mortality in the heart failure patient population.