Inflammation and chronic heart failure-potential therapeutic role of intravenous immunoglobulin

Cardiac dysfunction in sucrose-fed rats is associated with alterations of phospholamban phosphorylation and TNF-α levels

INTRODUCTION

High sucrose intake is linked to cardiovascular disease, a major global cause of mortality worldwide. Calcium mishandling and inflammation play crucial roles in cardiac disease pathophysiology.

OBJECTIVE

Evaluate if sucrose-induced obesity is related to deterioration of myocardial function due to alterations in the calcium-handling proteins in association with proinflammatory cytokines.

METHODS

Wistar rats were divided into control and sucrose groups. Over eight weeks, Sucrose group received 30% sucrose water. Cardiac function was determined in vivo using echocardiography and in vitro using papillary muscle assay. Western blotting was used to detect calcium handling protein; ELISA assay was used to assess TNF-α and IL-6 levels.

RESULTS

Sucrose led to cardiac dysfunction. RYR2, SERCA2, NCX, pPBL Ser16 and L-type calcium channels were unchanged. However, pPBL-Thr17, and TNF-α levels were elevated in the S group.

CONCLUSION

Sucrose induced cardiac dysfunction and decreased myocardial contractility in association with altered pPBL-Thr17 and elevated cardiac pro-inflammatory TNF-α.

Heart Failure in Rheumatic Disease: Secular Trends and Novel Insights

There is a significant increase in risk of heart failure in several rheumatic diseases. Common cardiovascular risk factors and inflammatory processes, present in both rheumatic diseases and heart failure, are contributing to this increase. The opportunities for using immune-based strategies to fight development of heart failure in rheumatic diseases are evolving. The diversity of inflammation calls for a tailored characterization of inflammation, enabling differentiation of inflammation and subsequent introduction of precision medicine using target-specific strategies and immunomodulatory therapy. As the field of rheuma-cardiology is still evolving, clear recommendations cannot be given yet.

Lupus acute cardiomyopathy is highly responsive to intravenous immunoglobulin treatment: Case series and literature review

INTRODUCTION

Intravenous immunoglobulin (IVIg) is currently used with considerable success for the treatment of many autoimmune diseases, including systemic lupus erythematosus (SLE). Among its various indications, IVIg has also been found to be beneficial in myocarditis, whether or not it is associated with an autoimmune disease. Nevertheless, data regarding IVIg treatment for myocarditis/cardiomyopathy in patients with SLE are sparse. The objective of this case series was to describe our experience with IVIg as a treatment for lupus myocarditis and to review the literature for IVIg for this indication.

PATIENT CONCERNS

We report 5 female patients with SLE, who presented with signs of acute heart failure including pulmonary congestion and arrhythmias.

DIAGNOSIS

Echocardiography demonstrated new reduced left ventricular ejection fraction of 20% to 30%. Two patients underwent coronary artery angiography, which demonstrated normal coronary arteries, supporting the diagnosis of myocarditis or nonischemic cardiomyopathy.

INTERVENTIONS

High-dose IVIg treatment was initiated in all 5 patients.

OUTCOMES

Following the treatment, clinical and echocardiographic improvement in cardiac function occurred within a few days to 1 month. This dramatic improvement persisted for several years.

CONCLUSION

Based on our case series, we believe that IVIg has an important role in the management of lupus acute cardiomyopathy. This safe, well-tolerated optional treatment should be considered, especially in severe cases.

Water-soluble alkaloids extracted from Aconiti Radix lateralis praeparata protect against chronic heart failure in rats via a calcium signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Many studies have shown the beneficial effects of aconite water-soluble alkaloid extract (AWA) in experimental models of heart disease, which have been ascribed to the presence of aconine, hypaconine, talatisamine, fuziline, neoline, and songorine. This study evaluated the effects of a chemically characterized AWA by chemical content, evaluated its effects in suprarenal abdominal aortic coarctation surgery (AAC)-induced chronic heart failure (CHF) in rats, and revealed the underlying mechanisms of action by proteomics.

METHODS

Rats were distributed into different groups: sham, model, and AWA-treated groups (10, 20, and 40 mg/kg/day). Sham rats received surgery without AAC, whereas model rats an AWA-treated groups underwent AAC surgery. after 8 weeks, the treatment group was fed AWA for 4 weeks, and body weight was assessed weekly. At the end of the treatment, heart function was tested by echocardiography. AAC-induced chronic heart failure, including myocardial fibrosis, cardiomyocyte hypertrophy, and apoptosis, was evaluated in heart tissue and plasma by RT-qPCR, ELISA, hematoxylin and eosin (H&E) staining, Masson's trichrome staining, TUNEL staining, and immunofluorescence staining of α-SMA, Col Ⅰ, and Col Ⅲ. Then, a proteomics approach was used to explore the underlying mechanisms of action of AWA in chronic heart failure.

RESULTS

AWA administration reduced body weight gain, myocardial fibrosis, cardiomyocyte hypertrophy, and apoptosis, and rats showed improvement in cardiac function compared to model group. The extract significantly ameliorated the AAC-induced altered expression of heart failure markers such as ANP, NT-proBNP, and β-MHC, as well as fibrosis, hypertrophy markers MMP-2 and MMP-9, and other heart failure-related factors including plasma levels of TNF-α and IL-6. Furthermore, the extract reduced the protein expression of α-SMA, Col Ⅰ, and Col Ⅲ in the left ventricular (LV), thus inhibiting the LV remodeling associated with CHF. In addition, proteomics characterization of differentially expressed proteins showed that AWA administration inhibited left ventricular remodeling in CHF rats via a calcium signaling pathway, and reversed the expression of RyR2 and SERCA2a.

CONCLUSIONS

AWA extract exerts beneficial effects in an AAC-induced CHF model in rats, which was associated with an improvement in LV function, hypertrophy, fibrosis, and apoptotic status. These effects may be related to the regulation of calcium signaling by the altered expression of RyR2 and SERCA2a.

SIRT3 Ablation Deteriorates Obesity-Related Cardiac Remodeling by Modulating ROS-NF-κB-MCP-1 Signaling Pathway

Obesity and the associated complications are a major public health issue as obesity incidence increases yearly, worldwide. Effects of obesity on heart failure have been reported previously. Obesity-related cardiac remodeling includes structural and functional dysfunctions, in which cardiac inflammation and fibrosis play a key role. The main mitochondrial deacetylase, SIRT3 participates in numerous cellular processes; however, its role in obesity-related cardiac remodeling remains unclear. In our study, high-fat diet (HFD) feeding induced downregulation of SIRT3 protein level in mice. SIRT3-KO mice fed on HFD exhibited higher cardiac dysfunction and cardiac remodeling compared with the wild-type controls. Further study revealed increases in collagen accumulation and inflammatory cytokine expression including MCP-1, IL-6, TGF-β, TNF-α in mice fed on HFD compared with chow diet, with higher levels observed in SIRT3-KO mice. Furthermore, significantly high levels of cardiac MCP-1 expression and macrophage infiltration, and ROS generation and activated NF-κB were observed in HFD-fed SIRT3-KO mice. We presumed that SIRT3 ablation-mediated MCP-1 upregulation is attributed to ROS-NF-κB activation. Thus, we concluded that SIRT3 prevents obesity-related cardiac remodeling by attenuating cardiac inflammation and fibrosis, through modulation of ROS-NF-κB-MCP-1 pathway.

Effects of steroidal saponins extract from Ophiopogon japonicus root ameliorates doxorubicin-induced chronic heart failure by inhibiting oxidative stress and inflammatory response

CONTEXT

Ophiopogonis Radix, the root of Ophiopogon japonicus (Thunb.) Ker-Gawl (Liliaceae), is a Traditional Chinese Medicine, which has been investigated to possess effective treatment of cardiovascular diseases.

OBJECTIVE

This study evaluates the cardioprotective effects of steroidal saponins extract from Ophiopogon japonicus (SOJ) root against doxorubicin-induced chronic heart failure (CHF) through the amelioration of oxidative stress and inflammation.

MATERIALS AND METHODS

A Sprague-Dawley rat model of CHF was established by intraperitoneally injected with DOX. All rats were randomly divided into four groups: Control group, CHF group, CHF + SOJ (100 mg/kg) treatment group, SOJ (100 mg/kg) treatment group (n = 8/group). After six weeks administration, biometric and echocardiography were measured. The levels of biochemical parameters were measured using commercial kits.

RESULTS

The values of LVESP, +dP/dtmax, -dP/dtmax, EF and FS increased to 116.20 ± 1.68 mmHg, 2978.71 ± 168.26 mmHg/s, 3452.61 ± 286.09 mmHg/s, 68.26 ± 5.28% and 31.97 ± 3.79%, respectively; the values of LVEDP, LVESD and LVEDD decreased to 8.85 ± 0.84 mmHg, 8.39 ± 0.45 mm and 12.36 ± 0.87 mm in CHF + SOJ group. In addition, the levels of IL-6, TNF-α and IL-1β decreased to 154.41 ± 7.72 pg/mg protein, 110.02 ± 6.96 pg/mg protein and 39.39 ± 5.27 pg/mg protein, respectively; the relative activity of p38 MAPK decreased to 2.60 ± 0.40 in CHF + SOJ group. Furthermore, the activities of SOD, CAT and GSH-Px increased to 268.77 ± 6.20 U/mg protein, 13.68 ± 0.68 U/mg protein and 316.90 ± 8.08 µmol/mg protein, and the content of MDA decreased to 4.03 ± 0.43 nmol/mg protein in CHF + SOJ group.

CONCLUSIONS

SOJ exerts the cardioprotective effect against DOX-induced CHF through suppressing inflammatory and oxidative stress. These results provide evidence that SOJ might be an effective treatment for CHF.

NFkappaB is a Key Player in the Crosstalk between Inflammation and Cardiovascular Diseases

Inflammation is a key mechanism of cardiovascular diseases. It is an essential component of atherosclerosis and a significant risk factor for the development of cardiovascular events. In the crosstalk between inflammation and cardiovascular diseases, the transcription factor NFκB seems to be a key player since it is involved in the development and progression of both inflammation and cardiac and vascular damage. In this review, we deal with the recent findings of the role of inflammation in cardiac diseases, focusing, in particular, on NFκB as a functional link. We describe strategies for the therapeutic targeting of NFκB as a potential strategy for the failing heart.

Selenium supplementation lowers insulin resistance and markers of cardio-metabolic risk in patients with congestive heart failure: a randomised, double-blind, placebo-controlled trial

This study was carried out to evaluate the effects of Se supplementation on metabolic profiles in patients with congestive heart failure (CHF). This randomised double-blind, placebo-controlled trial was performed among fifty-three subjects with CHF, aged 45–85 years old. Subjects were randomly allocated into two groups to take either 200 µg/d of Se as Se yeast (n 26) or placebo (n 27) for 12 weeks. Metabolic profiles were assessed at baseline and at the end of trial. Compared with the placebo, Se supplementation led to significant reductions in serum insulin (−18·41 (sd 27·53) v. +13·73 (sd 23·63) pmol/l, P<0·001), homoeostatic model of assessment for insulin resistance (−1·01 (sd 1·61) v. +0·55 (sd 1·20), P<0·001) and a significant increase in quantitative insulin sensitivity check index (QUICKI) (+0·007 (sd 0·03) v. −0·01 (sd 0·01), P=0·007). In addition, Se supplementation significantly decreased LDL-cholesterol (−0·23 (sd 0·29) v. −0·04 (sd 0·28) mmol/l, P=0·03) and total-:HDL-cholesterol ratio (−0·47 (sd 0·31) v. −0·06 (sd 0·42), P<0·001), and significantly increased HDL-cholesterol levels (+0·18 (sd 0·19) v. +0·02 (sd 0·13) mmol/l, P=0·001) compared with the placebo. In addition, taking Se supplements was associated with a significant reduction in high-sensitivity C-reactive protein (hs-CRP) (−1880·8 (sd 3437·5) v. +415·3 (sd 2116·5) ng/ml, P=0·01), and a significant elevation in plasma total antioxidant capacity (TAC) (+30·9 (sd 118·0) v. −187·9 (sd 412·7) mmol/l, P=0·004) and total glutathione levels (+33·7 (sd 130·4) v. −39·2 (sd 132·8) µmol/l, P=0·003) compared with the placebo. When we applied Bonferroni correction for multiple outcome testing, QUICKI (P=0·11), LDL-cholesterol (P=0·51), hs-CRP (P=0·17), TAC (P=0·06) and GSH (P=0·05) became non-significant, and other metabolic profiles did not alter. Overall, our study supported that Se supplementation for 12 weeks to patients with CHF had beneficial effects on insulin metabolism and few markers of cardio-metabolic risk.

Deficiency of NOD1 Improves the β-Adrenergic Modulation of Ca2+ Handling in a Mouse Model of Heart Failure

Heart failure (HF) is a complex syndrome characterized by cardiac dysfunction, Ca2+ mishandling, and chronic activation of the innate immune system. Reduced cardiac output in HF leads to compensatory mechanisms via activation of the adrenergic nervous system. In turn, chronic adrenergic overstimulation induces pro-arrhythmic events, increasing the rate of sudden death in failing patients. Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) is an innate immune modulator that plays a key role in HF progression. NOD1 deficiency in mice prevents Ca2+ mishandling in HF under basal conditions, but its role during β-adrenergic stimulation remains unknown. Here, we evaluated whether NOD1 regulates the β-adrenergic modulation of Ca2+ signaling in HF. Ca2+ dynamics were examined before and after isoproterenol perfusion in cardiomyocytes isolated from healthy and from post-myocardial infarction (PMI) wild-type (WT) and Nod1-/- mice. Isoproterenol administration induced similar effects on intracellular [Ca2+]i transients, cell contraction, and sarcoplasmic reticulum (SR)-Ca2+ load in healthy WT and Nod1-/- cells. However, compared with WT-PMI cells, isoproterenol exposure induced a significant increase in the [Ca2+]i transients and cell contraction parameters in Nod1-/--PMI cells, which mainly due to an increase in SR-Ca2+ load. NOD1 deficiency also prevented the increase in diastolic Ca2+ leak (Ca2+ waves) induced by isoproterenol in PMI cells. mRNA levels of β1 and β2 adrenergic receptors were significantly higher in Nod1-/--PMI hearts vs WT-PMI hearts. Healthy cardiomyocytes pre-treated with the selective agonist of NOD1, iE-DAP, and perfused with isoproterenol showed diminished [Ca2+]i transients amplitude, cell contraction, and SR-Ca2+ load compared with vehicle-treated cells. iE-DAP-treated cells also presented increased diastolic Ca2+ leak under β-adrenergic stimulation. The selectivity of iE-DAP on Ca2+ handling was validated by pre-treatment with the inactive analog of NOD1, iE-Lys. Overall, our data establish that NOD1 deficiency improves the β-adrenergic modulation of Ca2+ handling in failing hearts.

Sulforaphane, a Natural Isothiocyanate Compound, Improves Cardiac Function and Remodeling by Inhibiting Oxidative Stress and Inflammation in a Rabbit Model of Chronic Heart Failure

Background

The aim of this study was to investigate the effects of sulforaphane (SFN), a natural isothiocyanate compound, in a rabbit ascending aortic cerclage model of chronic heart failure (CHF).

Material/Methods

Thirty New Zealand White rabbits were divided into the sham operation group (n=10), the CHF group (n=10), and the CHF + SFN group (n=10) treated with subcutaneous SFN (0.5 mg/kg) for five days per week for 12 weeks. After 12 weeks, echocardiography and biometric analysis were performed, followed by the examination of the rabbit hearts. Enzyme-linked immunosorbent assay (ELISA) and Western blot were used to detect levels of inflammatory cytokines, superoxide dismutase (SOD), and malondialdehyde (MDA).

Results

In the CHF group, compared with the sham operation group, there was an increase in the heart weight to body weight ratio (HW/BW), the left ventricular weight to body weight ratio (LVW/BW), the left ventricular end diastolic diameter (LVEDD), the left ventricular end systolic diameter (LVESD), plasma brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) levels, the cardiac collagen volume fraction (CVF), apoptotic index, expression levels of collagen I, collagen III, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and malondialdehyde (MDA) in the myocardial tissue, and a decrease in the left ventricular shortening fraction (LVFS) and left ventricular ejection fraction (LVEF), and cardiac superoxide dismutase (SOD) activity. These changes were corrected in the SFN-treated group.

Conclusions

In a rabbit model of CHF, treatment with SFN improved cardiac function and remodeling by inhibiting oxidative stress and inflammation.

Fruit vinegars attenuate cardiac injury via anti-inflammatory and anti-adiposity actions in high-fat diet-induced obese rats

CONTEXT

Fruit vinegars (FVs) are used in Mediterranean folk medicine for their hypolipidemic and weight-reducing properties.

OBJECTIVE

To investigate the preventive effects of three types of FV, commonly available in Algeria, namely prickly pear [Opuntia ficus-indica (L.) Mill (Cectaceae)], pomegranate [Punica granatum L. (Punicaceae)], and apple [Malus domestica Borkh. (Rosaceae)], against obesity-induced cardiomyopathy and its underlying mechanisms.

MATERIALS AND METHODS

Seventy-two male Wistar rats were equally divided into 12 groups. The first group served as normal control (distilled water, 7 mL/kg bw), and the remaining groups were respectively treated with distilled water (7 mL/kg bw), acetic acid (0.5% w/v, 7 mL/kg bw) and vinegars of pomegranate, apple or prickly pear (at doses of 3.5, 7 and 14 mL/kg bw, acetic acid content as mentioned above) along with a high-fat diet (HFD). The effects of the oral administration of FV for 18 weeks on the body and visceral adipose tissue (VAT) weights, plasma inflammatory and cardiac enzymes biomarkers, and in heart tissue were evaluated.

RESULTS

Vinegars treatments significantly (p < .05) attenuated the HFD-induced increase in bw (0.2-0.5-fold) and VAT mass (0.7-1.8-fold), as well as increase in plasma levels of CRP (0.1-0.3-fold), fibrinogen (0.2-0.3-fold), leptin (1.7-3.7-fold), TNF-α (0.1-0.6-fold), AST (0.9-1.4-fold), CK-MB (0.3-1.4-fold) and LDH (2.7-6.7-fold). Moreover, vinegar treatments preserved myocardial architecture and attenuated cardiac fibrosis.

DISCUSSION AND CONCLUSION

These findings suggest that pomegranate, apple and prickly pear vinegars may prevent HFD-induced obesity and obesity-related cardiac complications, and that this prevention may result from the potent anti-inflammatory and anti-adiposity properties of these vinegars.

Plasma-derived exosomes contribute to inflammation via the TLR9-NF-κB pathway in chronic heart failure patients

Exosomes are small vesicles that contain proteins, DNA and RNA, and play an important role in inflammation; however, the underlying mechanism remains unclear. In the present study, we found increased plasma-derived exosomes in chronic heart failure patients compared with healthy controls. Further, our data demonstrated that plasma-derived exosomes carried mtDNA, and triggered an inflammatory response via the TLR9-NF-κB pathway, as well, the inflammatory effect was closely related to exosomal mtDNA copy number. However, the effect could be blocked by chloroquine (CQ), a TLR9 inhibitor. These findings reveal a new mechanism of exosome-induced inflammation, and provide a new perspective for intervention and treatment of inflammation-related diseases, such as chronic heart failure.

Oxidative stress and inflammatory markers - the future of heart failure diagnostics?

Heart failure remains one of the most important problems in cardiology despite the progress in its treatment. A number of recent studies have demonstrated the relationship between the intensification of oxidative stress and chronic inflammation and the severity of left ventricular dysfunction, development of heart failure symptoms, and prediction of future cardiac events. Early detection of changes developing in the heart is key in improving the treatment's effectiveness. It appears that determining specific, sensitive biomarkers reflecting the complex pathophysiology of heart failure and using them to detect asymptomatic cardiac alterations may become a crucial screening tool, assisting in the identification of patients requiring further diagnostic examinations. This article presents an overview of the current knowledge of the role of oxidative stress and inflammation in heart failure; it also discusses the potential role of oxidative stress and inflammatory markers as prognostic factors in heart failure that may be used in screening tests.

A newly designed curcumin analog Y20 mitigates cardiac injury via anti-inflammatory and anti-oxidant actions in obese rats

Obesity is strongly associated with the cause of structural and functional changes of the heart in both human and animal models. Oxidative stress and inflammation play a critical role in the development of obesity-induced cardiac disorders. Curcumin is a natural product from Curcuma Longa with multiple bioactivities. In our previous study, in order to reach better anti-inflammatory and anti-oxidant dual activities, we designed a new mono-carbonyl curcumin analog, Y20, via the structural modification with both trifluoromethyl and bromine. This study was designed to investigate the protective effects of Y20 on obesity-induced cardiac injury and its underlying mechanisms. In high fat diet–fed rats, oral administration of Y20 at 20 mg/kg or curcumin at 50 mg/kg significantly decreased the cardiac inflammation and oxidative stress and eventually improved the cardiac remodeling by mitigating cardiac disorganization, hypertrophy, fibrosis and apoptosis. Y20 at 20 mg/kg showed comparable and even stronger bioactivities than curcumin at 50 mg/kg. The beneficial actions of Y20 are closely associated with its ability to increase Nrf2 expression and inhibit NF-κB activation. Taken together, these results suggest that Y20 may have a great therapeutic potential in the treatment of obesity-induced cardiac injury using Nrf2 and NF-κB as the therapeutic targets for treating obesity-related disorders.

Association of the degree of adiposity and duration of obesity with measures of cardiac structure and function: the CARDIA study

OBJECTIVE

Examine whether there are independent influences of a greater degree of adiposity and longer duration of obesity on cardiac structure and function.

METHODS

Participants of CARDIA were 18-30 years when they underwent a baseline examination in 1985-86. Seven follow-up examinations were conducted every 2-5 years.

RESULTS

Among 2,547 participants who underwent an echocardiogram at the year 25 examination and were not obese at baseline, 34.4 and 35.5% were overall (BMI ≥ 30 kg m(-2) ) and abdominally obese (waist circumference: men: >102 cm; women: >88 cm) at year 25, respectively. A greater degree of overall and abdominal adiposity at year 25 were each associated with a greater left ventricular (LV) mass (P < 0.001), LV volume (P < 0.001), LV mass-to-volume ratio (P < 0.001), left atrial dimension (P < 0.001), and ejection fraction (P < 0.05) after adjustment for duration of obesity and other risk factors. In contrast, a longer duration of overall obesity was associated with a greater LV mass (P = 0.003) and a trend for a lower ejection fraction (P = 0.07).

CONCLUSIONS

A greater degree of adiposity is strongly associated with concentric LV remodeling in midlife, while the cumulative effects of a longer duration of overall obesity during young adulthood contribute to concentric remodeling predominantly by increasing LV mass.

Interleukin-1β reduces L-type Ca2+ current through protein kinase Cϵ activation in mouse heart

Inflammation is now widely recognized as a key component of heart disease. Patients suffering from arrhythmias and heart failure have increased levels of tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β). Evidence suggests that these cytokines are important mediators of cardiac remodeling; however, their effects on ion channels and arrhythmogenesis remain incompletely understood. The L-type Ca(2+) current (ICaL) is a major determinant of the plateau phase of cardiac action potential and has a critical excitation-contraction coupling role. Thus, altering its properties could have detrimental effects on cardiac electrical and contractile functions. Accordingly, the objective of this study was to elucidate the effect of TNFα and IL-1β on ICaL, while exploring the underlying regulatory mechanisms. Neonatal mouse ventricular myocytes were treated with a pathophysiological concentration (30 pg/ml) of TNFα and IL-1β for 24 h. Voltage-clamp recordings showed that TNFα had no effect on ICaL, whereas IL-1β decreased the current density by 36%. Although both IL-1β- and TNFα-treated myocytes showed significant increase in reactive oxidative species (ROS), Western blot experiments revealed that only IL-1β increased PKCϵ membrane translocation. The antioxidant N-acetyl-L-cysteine normalized ROS levels and restored ICaL density. Furthermore, the PKCϵ translocation inhibitor ϵ-V1-2 blocked the effect of IL-1β on ICaL. The reduction of ICaL by IL-1β was also seen in cultured adult ventricular myocytes. Overall, chronic IL-1β treatment decreased ICaL density in cardiomyocytes. These effects implicated ROS signaling and PKCϵ activation. These findings could contribute to explain the role of IL-1β in the development of arrhythmia and heart failure.

Resistance training may concomitantly benefit body composition, blood pressure and muscle MMP-2 activity on the left ventricle of high-fat fed diet rats

OBJECTIVE

The purpose of this study was to evaluate the effect of resistance training (RT) on body composition, systolic and diastolic blood pressures (BP), and activity of muscle MMP-2 in the left ventricle of high-fat fed rats.

MATERIALS/METHODS

We have evaluated 32 male Wistar rats divided into four experimental groups (n=8/each) according to diet and exercise status: sedentary (SED; standard diet), sedentary obese (SED-OB; diet: 30% of fat), RT (RT; standard diet) and RT obese (RT-OB; diet: 30% of fat). After weaning (day 21), animals were subjected to the experimental diet according to their groups during 24 weeks. A 12-week strength-training period was used, during which the rats climbed a 1.1-m vertical ladder with weights attached to their tails. Sessions were performed three times/week (Mondays, Wednesdays and Fridays), with 4-9 climbs/session and 8-12 dynamic movements/climb.

RESULTS

RT induced higher muscle MMP-2 activity in the left ventricle in RT and RT-OB groups. Moreover, this study demonstrated that RT promoted lower body and fat masses, fat percentage, systolic and diastolic BPs and higher fat free mass in both trained groups.

CONCLUSION

RT increased muscle MMP-2 activity in the left ventricle, induced positive changes on body composition and lowered BPs in high-fat diet fed rats, suggesting that it may be a useful tool to prevent alterations induced by high-fat diet consumption.

Resveratrol alleviates endotoxin-induced myocardial toxicity via the Nrf2 transcription factor

Background/Aims

Septic cardiomyopathy is a severe condition that remains a challenge for clinical management. This study investigated whether the natural polyphenolic compound resveratrol could be used as a prophylactic treatment to alleviate sepsis-related myocardial injury; the underlying molecular mechanisms were deciphered by both in vitro and in vivo experiments.

Methods

A mouse model of endotoxin-induced cardiomyopathy was developed by intraperitoneal injection of LPS, and resveratrol was administered prophylatically to the animals. Serum LDH and CK activities were measured to detect myocardial injury, and echocardiography was performed to monitor cardiac structure and function. Various cytokines/chemokines and the Nrf2 antioxidant defense system were examined in the heart tissue. The effects of resveratrol on LPS-induced Nrf2 activation, ROS generation, and apoptotic cell death were further investigated in cultured primary human cardiomyocytes. An Nrf2 specific siRNA was used to define its role in resveratrol-mediated cardiomyocyte protective effect.

Results

Resveratrol pretreatment significantly attenuated LPS-induced myocardial injury in mice, which was associated with suppressed proinflammatory cytokine production and enhanced Nrf2 activation in the heart. In cultured primary human cardiomyocytes, resveratrol activated Nrf2, inhibited LPS-induced ROS generation, and effectively protected the cells from LPS-induced apoptotic cell death. Knockdown of Nrf2 abrogated resveratrol-mediated protection of the cells from LPS-induced cell death.

Conclusion

Resveratrol effectively alleviates endotoxin-induced cardiac toxicity through mechanisms that involve the Nrf2 antioxidant defense pathway. Our data suggest that resveratrol might be developed as a useful prophylactic management for septic cardiomyopathy.

Bedside-Friendly Prediction for Presence of Post-Myocardial lnfarction Systolic Dysfunction Using Multimarker Panel: Integrating Salivary Diagnostics into Clinical Practice

BACKGROUND AND OBJECTIVES

We investigated if a combination of plasma or salivary interleukin-2 (IL-2), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), transforming growth factor-beta (TGF-β), and troponin can improve estimation of the pretest probability of the left ventricular systolic dysfunction (LVSD).

SUBJECTS AND METHODS

Eighty patients with newly-diagnosed myocardial infarction (MI) were echocardiographically examined for LVSD (ejection fraction ≤40%). Measurements included traditional MI risk factors, plasma and salivary concentrations of troponin, IL-2, IL-6, TNF-α, and TGF-β. With the LVSD as the outcome variable, we developed logistic regression models, starting with a basic model incorporating traditional risk factors and consecutively adding salivary and plasma biomarkers. Models were compared using several criteria, including (but not limited to) C statistic (discrimination) and net reclassification improvement index (NRI).

RESULTS

APART FROM TROPONIN, PLASMA, AND SALIVARY VALUES OF THE BIOMARKERS WERE CORRELATED: spearman's ρ was 0.19 (p=0.088) for troponin, 0.36 (p=0.001) for IL-2, 0.74 (p<0.001) for IL-6, 0.61 (p<0.001) for TNF-α, and 0.65 (p<0.001) for TGF-β. The predictive performances of the basic model for estimating the pretest probability of the presence of LVSD considerably improved when cytokines were added (salivary added: C-statistic from 0.77 to 0.82 and NRI 77%; plasma added: C-statistic to 0.80 and NRI 134%).

CONCLUSION

Multiple biomarkers added diagnostic value to the standard risk factors for predicting the presence of post-MI LVSD.

TNF-α-secreting B cells contribute to myocardial fibrosis in dilated cardiomyopathy

PURPOSE

Excessive inflammation responses mediated by CD4(+) T cells contributes to myocardial fibrosis in dilated cardiomyopathy (DCM) resulting from viral myocarditis. Recently, some scholars discovered that B cells harbored an abnormal pro-inflammatory capacity besides the production of autoantibodies. Thus, we aimed to explore whether and which type of B cells act on myocardial fibrosis in DCM.

METHODS

A total of 56 newly hospitalized DCM patients were studied, and among these, 17 patients accepted the gadolinium enhanced cardiovascular magnetic resonance imaging (MRI) for myocardial fibrosis evaluations.

RESULTS

B cell functions including the frequency and proliferation were significantly elevated in DCM patients. After screening the important cytokines including IL-1β, IL-6, IL-10, IL-17, TNF-α and TGF-β produced in these B cells by flow cytometry, we found that only the TNF-α-secreting B cells were obviously increased. Furthermore, the TNF-α protein secretion and mRNA levels were also enhanced in LPS-stimulated B cell isolated from DCM patients. In addition, 10 patients (59%) with increased TNF-α-secreting B cells showed late enhancement and boosted serum procollagen type III compared with the other 7 patients (41%) whose enhancement could not be detected. Moreover, the frequencies of TNF-α-secreting B cells were negatively correlated with LVEF and positively correlated with LVEDD, NT-proBNP and procollagen type III in all of the DCM patients.

CONCLUSIONS

Our study firstly suggested that TNF-α-secreting B cells were involved in myocardial fibrosis, which revealed the new pathogenic mechanism of B cells in DCM, and therapeutic targets against these cells might be valuable.

IL-10 inhibits inflammation and attenuates left ventricular remodeling after myocardial infarction via activation of STAT3 and suppression of HuR

Persistent inflammatory response has adverse effects on left ventricular (LV) function and remodeling following acute myocardial infarction. We hypothesized that suppression of inflammation with interleukin (IL)-10 treatment attenuates LV dysfunction and remodeling after acute myocardial infarction. After the induction of acute myocardial infarction, mice were treated with either saline or recombinant IL-10, and inflammatory response and LV functional and structural remodeling changes were evaluated. IL-10 significantly suppressed infiltration of inflammatory cells and expression of proinflammatory cytokines in the myocardium. These changes were associated with IL-10-mediated inhibition of p38 mitogen-activated protein kinase activation and repression of the cytokine mRNA-stabilizing protein HuR. IL-10 treatment significantly improved LV functions, reduced infarct size, and attenuated infarct wall thinning. Myocardial infarction-induced increase in matrix metalloproteinase (MMP)-9 expression and activity was associated with increased fibrosis, whereas IL-10 treatment reduced both MMP-9 activity and fibrosis. Small interfering RNA knockdown of HuR mimicked IL-10-mediated reduction in MMP-9 expression and activity in NIH3T3 cells. Moreover, IL-10 treatment significantly increased capillary density in the infarcted myocardium which was associated with enhanced STAT3 phosphorylation. Taken together, our studies demonstrate that IL-10 suppresses inflammatory response and contributes to improved LV function and remodeling by inhibiting fibrosis via suppression of HuR/MMP-9 and by enhancing capillary density through activation of STAT3.

Cardiac remodeling in obesity

The dramatic increase in the prevalence of obesity and its strong association with cardiovascular disease have resulted in unprecedented interest in understanding the effects of obesity on the cardiovascular system. A consistent, but puzzling clinical observation is that obesity confers an increased susceptibility to the development of cardiac disease, while at the same time affording protection against subsequent mortality (termed the obesity paradox). In this review we focus on evidence available from human and animal model studies and summarize the ways in which obesity can influence structure and function of the heart. We also review current hypotheses regarding mechanisms linking obesity and various aspects of cardiac remodeling. There is currently great interest in the role of adipokines, factors secreted from adipose tissue, and their role in the numerous cardiovascular complications of obesity. Here we focus on the role of leptin and the emerging promise of adiponectin as a cardioprotective agent. The challenge of understanding the association between obesity and heart failure is complicated by the multifaceted interplay between various hemodynamic, metabolic, and other physiological factors that ultimately impact the myocardium. Furthermore, the end result of obesity-associated changes in the myocardial structure and function may vary at distinct stages in the progression of remodeling, may depend on the individual pathophysiology of heart failure, and may even remain undetected for decades before clinical manifestation. Here we summarize our current knowledge of this complex yet intriguing topic.

Effects of testosterone on cytokines and left ventricular remodeling following heart failure

AIMS

To investigate the effects of testosterone treatment on cytokines, ventricular remodeling in rats with heart failure.

MATERIALS AND METHODS

Sprague-Dawley male rats with heart failure were divided into testosterone (n = 22) and placebo (n = 22) group. Pseudo surgery was performed on a third group of 15 male rats as control.

RESULTS

Compared with the placebo group, the testosterone group had a greater LVEF (P <0.05), a higher serum IL-10 level (P <0.05) and a lower serum TNF-alpha level (P<0.05). The expression of TNF-alpha mRNA, MMP-9 mRNA and the myocardial hydroxyproline contents in the testosterone group were also lower than in the placebo group (P<0.05). The mortality rate in the testosterone and placebo group was 31.8% and 68.2%, respectively (P <0.05).

CONCLUSION

Serum testosterone levels were decreased significantly in male rats with heart failure. Testosterone treatment diminishes the imbalance between interleukin-10 and TNF-alpha, suppresses ventricular remodeling and improves cardiac function.

Activation of immune and inflammatory systems in chronic heart failure: novel therapeutic approaches

Despite extensive research and novel treatments, chronic heart failure (CHF) remains a cause of high morbidity and mortality. Mounting evidence suggested that immune activation and inflammation play critical roles in the pathogenesis of CHF. In this review, we examine the current evidence regarding this contemporary pathophysiological mechanism, and evaluate the effects of conventional and novel cardiovascular drugs, such as calcium sensitisers and statins, on the immune and inflammatory mediator's network. Although therapies, which specifically antagonise tumour necrosis factor-alpha have not demonstrated considerable benefit in patients with CHF, there is an increasing evidence to suggest greater value from non-specific anti-inflammatory approaches, including: pentoxifylline, intravenous immunoglobulin, immune modulation therapy, growth hormones, physical training and nutrition regulation. Several innovative therapeutic targets, such as peroxisome proliferator-activated receptor gamma activators, Rho-kinase, p38 mitogen-activated protein kinase, nuclear transcription factor NF-kappaB, recovering or augmenting parasympathetic tone, cardiac resynchronisation therapy, macrophage inhibitors and chemokine receptor antagonists, are briefly discussed in this review. While we have recently demonstrated the potential merits of combining low-dose methotrexate with conventional therapy, through extensively modulating the activated immune and inflammatory mediator's network, there is a need for further rigorous research of this complex network, especially involving current promising therapies which modulate this system. Such evidence has the potential to revolutionise changes for the management of this disorder. Based on the 'heterogeneity' of immune activation and inflammation among different CHF populations, an 'optimised combination treatment' may offer exciting benefits for individual therapy in the future.

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.

Atrial fibrillation is associated with increased neurohumoral activation and reduced exercise tolerance in patients with non-ischemic dilated cardiomyopathy

OBJECTIVES

To assess atrial fibrillation (AF) associated differences in proinflammatory cytokines, natriuretic peptide levels and exercise capacity in patients with heart failure (HF) secondary to non-ischemic dilated cardiomyopathy (NIDC).

METHODS

We studied 147 NIDC patients, mean age 58.3+/-12.5 years, left ventricular (LV) ejection fraction 27.8+/-10.9% and NYHA class II-III. Neurohumoral activation was assessed by measurement of interleukin IL-1, IL-6, tumor necrosis factor-a (TNF-a), its soluble receptors sTNFR I and II, N-terminal atrial (NT-ANP) and -brain (NT-BNP) natriuretic peptide levels, and functional class was assessed by cardiopulmonary exercise test.

RESULTS

Forty patients (27.5%) had chronic AF and they did not differ in age, LV ejection fraction or HF duration compared to patients in sinus rhythm (SR). AF was associated with increased levels of IL-6 (p=0.001), TNF-a (p=0.002), sTNFRI (p=0.023), NT-ANP (p<0.001) and NT-BNP (p=0.003), decreased exercise duration (p<0.001) and slightly reduced maximal oxygen consumption at peak exercise (p=0.07) compared to SR patients. No significant differences in cytokine and natriuretic peptide levels or exercise tolerance were noted when patients in AF were compared to the subgroup of SR with restrictive LV filling pattern. Multivariate analysis showed that NT-ANP (p=0.003) and IL-6 (p=0.006) plasma levels were independently associated with the presence of AF in our patient population.

CONCLUSION

AF is associated with increased inflammatory state, natriuretic peptide levels and reduced exercise capacity in patients with HF secondary to NIDC. These findings suggest that the presence of AF in HF represents a more advanced stage of the syndrome.

Targets for immunomodulation in cardiovascular disease – where are we now?

The recognition that inflammation plays an important role in most cardiovascular pathologies offers the potential for the development of new therapeutic targets. Heart failure and in-stent restenosis are two areas in which there have been very recent developments in identifying and targeting potential inflammatory mediators. The development of both broad anti-inflammatory strategies and more targeted approaches have confirmed that immunomodulation may have a beneficial effect on disease progression of restenosis and heart failure in experimental animals, while the results from clinical studies highlight the need to consider the inflammatory processes as a whole, rather than some aspects in isolation. This review briefly summarizes the key stimuli for initiating inflammation in cardiovascular disease, recent clinical and experimental developments in the search for appropriate anti-inflammatory strategies and considers the possible pitfalls and future challenges for developing this area.