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Background and purpose ST2 is one of the interleukin (IL)-1 receptor family members comprising of membrane-bound (ST2L) and soluble (sST2) isoforms. Clinical trials have revealed that serum sST2 levels predict outcome in patient with myocardial infarction or chronic heart failure (HF). Meanwhile, we and others have reported that ablation of ST2 caused exaggerated cardiac remodeling in both ischemic and non-ischemic HF. Here, we tested whether IL-33, the ligand for ST2, protects myocardium against HF induced by mechanical overload using ligand specific knockout (IL-33 −/− ) mice. Methods and results Transverse aortic constriction (TAC)/sham surgery were carried out in both IL-33 and WT-littermates. Echocardiographic measurements were performed at frequent interval during the study period. Heart was harvested for RNA and histological measurements. Following mechanical overload by TAC, myocardial mRNA expressions of Th1 cytokines, such as TNF-α were enhanced in IL-33 −/− mice than in WT mice. After 8-weeks, IL-33 −/− mice exhibited exacerbated left ventricular hypertrophy, increased chamber dilation, reduced fractional shortening, aggravated fibrosis, inflammation, and impaired survival compared with WT littermates. Accordingly, myocardial mRNA expressions of hypertrophic (c-Myc/BNP) molecular markers were also significantly enhanced in IL-33 −/− mice than those in WT mice. Conclusions We report for the first time that ablation of IL-33 directly and significantly leads to exacerbate cardiac remodeling with impaired cardiac function and survival upon mechanical stress. These data highlight the cardioprotective role of IL-33/ST2 system in the stressed myocardium and reveal a potential therapeutic role for IL-33 in non-ischemic HF.

Diabetic nephropathy is characterized by a plethora of signaling abnormalities. Recent trials have suggested that intensive glucose-lowering treatment leads to hypoglycemic events, which can be dangerous. Curcumin is the active ingredient of turmeric, which has been widely used in many countries for centuries to treat numerous diseases. The preventive and therapeutic properties of curcumin are associated with its antioxidant and anti-inflammatory properties. Here, we highlight the renoprotective role of curcumin in diabetes mellitus (DM) with an emphasis on the molecular basis of this effect. We also briefly discuss the numerous approaches that have been undertaken to improve the pharmacokinetics of curcumin.

Edaravone, a novel antioxidant, acts by trapping hydroxyl radicals, quenching active oxygen and so on. Its cardioprotective activity against experimental autoimmune myocarditis (EAM) was reported. Nevertheless, it remains to be determined whether edaravone protects against cardiac remodelling in dilated cardiomyopathy (DCM). The present study was undertaken to assess whether edaravone attenuates myocardial fibrosis, and examine the effect of edaravone on cardiac function in rats with DCM after EAM. Rat model of EAM was prepared by injection with porcine cardiac myosin 28 days after immunization, we administered edaravone intraperitoneally at 3 and 10 mg/kg/day to rats for 28 days. The results were compared with vehicle-treated rats with DCM. Cardiac function, by haemodynamic and echocardiographic study and histopathology were performed. Left ventricular (LV) expression of NADPH oxidase subunits (p47(phox), p67(phox), gp91(phox) and Nox4), fibrosis markers (TGF-β(1) and OPN), endoplasmic reticulum (ER) stress markers (GRP78 and GADD 153) and apoptosis markers (cytochrome C and caspase-3) were measured by Western blotting. Edaravone-treated DCM rats showed better cardiac function compared with those of the vehicle-treated rats. In addition, LV expressions of NADPH oxidase subunits levels were significantly down-regulated in edaravone-treated rats. Furthermore, the number of collagen-III positive cells in the myocardium of edaravone-treated rats was lower compared with those of the vehicle-treated rats. Our results suggest that edaravone ameliorated the progression of DCM by modulating oxidative and ER stress-mediated myocardial apoptosis and fibrosis.

Aim Recent findings have suggested that a therapeutic approach to amplify or stimulate the angiotensin-converting enzyme-2 [ACE-2]-angiotensin 1–7 [ANG 1–7] mas axis could provide protection against the development of cardiovascular diseases. We investigated the cardioprotective effects of telmisartan in rats with dilated cardiomyopathy [DCM] after experimental autoimmune myocarditis [EAM]. Main methods DCM was elicited in Lewis rats by immunization with cardiac myosin, and twenty-eight days after immunization, the surviving Lewis rats were divided into two groups and treated with either telmisartan (10 mg/kg/day) or vehicle. Key findings Telmisartan treatment effectively suppressed myocardial protein and mRNA expressions of inflammatory markers [CD68, iNOS, NF-kB, interleukin-1β, interferon-γ, monocyte chemotactic protein-1] in comparison to vehicle-treated rats. In contrast, myocardial protein levels of ACE-2 and ANG 1–7 mas receptor were upregulated in the telmisartan-treated group compared with vehicle-treated rats. Telmisartan treatment significantly reduced fibrosis and hypertrophy and their marker molecules [OPN, CTGF, TGF-β1 and collagens I and III and atrial natriuretic peptide and GATA-4, respectively] compared with those of vehicle-treated rats. In addition, telmisartan treatment significantly lowered the protein expressions of NADPH oxidase subunits p47phox, p67phox, and superoxide production when compared with vehicle-treated rats. Telmisartan treatment significantly decreased the expression levels of mitogen-activated protein kinase (MAPK) signaling molecules than with those of vehicle-treated rats. Also, telmisartan treatment significantly improved LV systolic and diastolic function. Significance These results indicate that telmisartan treatment significantly improved LV function and ameliorated the progression of cardiac remodeling through the modulation of ACE-2/ANG 1–7/Mas receptor axis in rats with DCM after EAM.

Mulberry is commonly used as silkworm diet and an alternative medicine in Japan and China, has recently reported to contain many antioxidative flavanoid compounds and having the free radical scavenging effects. Antioxidants reduce cardiac oxidative stress and attenuate cardiac dysfunction in animals with pacing-induced congestive heart failure. Hence we investigated the cardioprotective effect of mulberry leaf powder in rats with experimental autoimmune myocarditis. Eight-week-old Lewis rats immunized with cardiac myosin were fed with either normal chow or a diet containing 5% mulberry leaf powder and were examined on day 21. ML significantly decreased oxidative stress, myocyte apoptosis, cellular infiltration, cardiac fibrosis, mast cell density, myocardial levels of sarco/endo-plasmic reticulum Ca(2+) ATPase2, p22(phox), receptor for advanced glycation end products, phospho-p38 mitogen activated protein kinase, phospho-c-Jun NH(2)-terminal protein kinase, glucose regulated protein78, caspase12 and osteopontin levels in EAM rats. These results may suggest that mulberry diet can preserve the cardiac function in experimental autoimmune myocarditis by modulating oxidative stress induced MAPK activation and further afford protection against endoplasmic reticulum stress mediated apoptosis.

Excess cytokine produced by inflammatory stimuli contributes to the progression of myocardial damage in myocarditis. Angiotensin-II has been shown to play a pivotal role in the pathophysiology of various organs, especially the cardiovascular system. Some angiotensin II type 1 receptor antagonists are reported to inhibit proinflammatory cytokine production in vitro and in vivo. We investigated whether telmisartan, an angiotensin II type 1 receptor antagonist protects against experimental autoimmune myocarditis by suppression of inflammatory cytokines and oxidative stress. Experimental autoimmune myocarditis was induced in Lewis rats by immunization with porcine cardiac myosin. The rats were divided into two groups and treated with either telmisartan (10 mg/kg/day) or vehicle for 21 days. Age-matched normal rats without immunization were also included in this study. Myocardial functional parameters were significantly improved by treatment with telmisartan compared with vehicle-treated rats. Increased myocardial mRNA expressions of inflammatory cytokines [interleukin (IL-6), IL-1β, tumor necrosis factor-α and interferon-γ] were also suppressed by telmisartan treatment compared with vehicle-treated rats. Myocardial protein expressions of NADPH oxidase subunits p47phox, Nox-4, and gp91phox, myocardial levels of 8-hydroxydeoxyguanosine and 4-hydroxy-2-nonenal, and myocardial apoptosis were also significantly decreased by telmisartan treatment compared with vehicle-treated rats. Further, telmisartan significantly decreased endoplasmic reticulum stress markers in experimental autoimmune myocarditis rats. These findings suggest that telmisartan protects against experimental autoimmune myocarditis in rats, at least in part by suppressing inflammatory cytokines and oxidative stress; however, further investigations are needed before clinical use.

Curcumin is a natural polyphenolic compound abundant in the rhizome of the perennial herb turmeric, Curcuma longa. It is commonly used as a dietary spice and coloring agent in cooking, and is used anecdotally as an herb in traditional Indian and Chinese medicine. It has been reported that curcumin has the potential to protect against cardiac inflammation through suppression of GATA-4 and nuclear factor-κB (NF-κB); however, no study to date has addressed the effect of curcumin on experimental autoimmune myocarditis (EAM) in rats. In this study, 8-week-old male Lewis rats were immunized with cardiac myosin to induce EAM. They were then divided randomly into a treatment or vehicle group and orally administrated curcumin (50 mg/kg/d) or 1% gum arabic, respectively, for 3 weeks after myosin injection. We performed hemodynamic, echocardiographic, hematoxylin and eosin staining, mast cell staining and Western blotting studies to evaluate the protective effect of curcumin in the acute phase of EAM. Cardiac functional parameters measured by hemodynamic and echocardiographic studies were significantly improved by curcumin treatment. Furthermore, curcumin reduced the heart weight-to-body weight ratio, area of inflammatory lesions and the myocardial protein level of NF-κB, interleukin (IL)-1β, tumor necrosis factor (TNF)-α and GATA-4. Our results indicate that curcumin has the potential to protect against cardiac inflammation through suppression of IL-1β, TNF-α, GATA-4 and NF-κB expresses, and may provide a novel therapeutic strategy for autoimmune myocarditis.

Favorable effects of angiotensin II type 1 receptor blockers on patients with ischemic or idiopathic dilated cardiomyopathy (DCM) have already been suggested by several human trials, but their effects on DCM remain unknown. Hence, we investigated the effect of olmesartan on myocardial remodeling in a rat model in which myosin-induced experimental autoimmune myocarditis (EAM) might develop into DCM. EAM was elicited in Lewis rats by immunization with cardiac myosin, and 28 d after immunization, the surviving Lewis rats were divided into two groups and treated with either olmesartan (10 mg/kg/d) or vehicle. Age-matched normal rats without immunizations were also used. After four weeks of treatment, we investigated the effects of olmesartan on cardiac function, inflammatory cytokines and cardiac remodeling in EAM rats. Myocardial functional parameters measured by hemodynamic and echocardiographic analyses were significantly improved by the treatment with olmesartan compared with those of vehicle-treated rats. Olmesartan significantly reduced cardiac fibrosis as well as hypertrophy and its molecular markers (left ventricular [LV] mRNA expressions of transforming growth factor beta1, collagen-I and -III, and atrial natriuretic peptide) compared with those of vehicle-treated rats. Increased myocardial mRNA expressions of proinflammatory cytokines (interleukin [IL]-6, IL-1β), monocyte chemoattractant protein-1 and matrix metalloproteinases (MMP-2 and -9) were also suppressed by the treatment with olmesartan in rats with DCM. Further, the plasma level of angiotensin II was significantly increased in olmesartan-treated rats. These findings demonstrate that olmesartan treatment significantly improved LV function and ameliorated the progression of cardiac remodeling in rats with DCM after EAM.

Daunorubicin (DNR) is one of the anthracycline anti-tumor agents widely used in the treatment of acute myeloid leukemia. However, the clinical use of DNR has been limited by its undesirable systemic toxicity, especially in the heart and kidney. This study was designed to test the effectiveness of carvedilol, a nonselective beta-blocker against DNR-induced cardiotoxicity and nephrotoxicity. Rats were treated with a cumulative dose of 9 mg/kg body weight DNR (i.v.). Carvedilol was administered orally every day for 6 weeks. DNR rats showed cardiac and nephrotoxicities as evidenced by worsening cardiac and kidney functions, which were evaluated by hemodynamic and echocardiographic studies, and by measuring protein in urine, levels of urea and creatinine in serum, lipid profiles, malondialdeyde level and the total level of glutathione peroxidase activity in both heart and kidney tissues. These changes were reversed by treatment with carvedilol, which resulted in significant improvement in the cardio-renal function. Furthermore, carvedilol down-regulated matrix metalloproteinase-2 expression in the heart, increased nephrin expression in the kidney, and attenuated the increased protein expression of NADPH oxidase subunits in heart and kidney. Moreover, carvedilol reduced myocardial and renal apoptosis and improved the histopathological changes in heart and kidney induced by DNR. In conclusion, the present study demonstrated a beneficial effect of carvedilol treatment in the prevention of DNR-induced cardiotoxicity and nephrotoxicity by reversing the oxidative stress and apoptosis.

Multiple trials over the past several years have examined indications for angiotensin receptor blockers (ARBs) in the treatment of left ventricular (LV) dysfunction, both acutely after myocardial infarction and in chronic heart failure (CHF). However, the effects of telmisartan, an ARB in rats with CHF after experimental autoimmune myocarditis (EAM) have not yet been analyzed. CHF was elicited in Lewis rats by immunization with cardiac myosin, and 28 days after immunization, the surviving Lewis rats were divided into two groups and treated with either telmisartan (10 mg kg(-1) day(-1)) or vehicle. After 4 weeks of treatment, we analyzed the effects of telmisartan on cardiac function, proinflammatory cytokines and cardiac remodeling in EAM rats. Myocardial functional parameters measured by hemodynamic and echocardiographic studies were significantly improved by telmisartan treatment in rats with CHF compared with those of vehicle-treated rats with CHF. Telmisartan significantly reduced levels of cardiac fibrosis, hypertrophy and its marker molecules (LV mRNA expressions of transforming growth factor beta 1, collagen I and III, and atrial natriuretic peptide), and peroxisome proliferator-activated receptor--gamma protein expression compared with those of vehicle-treated rats. CHF-induced increases in myocardial mRNA expressions of proinflammatory cytokines, (interleukin (IL)-6, IL-1beta), monocyte chemoattractant protein-1 and matrix metalloproteinases (MMP-2 and -9) were also suppressed by the treatment with telmisartan. Moreover, the plasma level of angiotensin-II was significantly elevated in telmisartan-treated rats. Our results indicate that telmisartan treatment significantly improved LV function and ameliorated the progression of cardiac remodeling in rats with CHF after EAM.

Diabetes mellitus increases the risk of heart failure independently of underlying coronary artery disease, and many believe that diabetes leads to cardiomyopathy. The underlying pathogenesis is partially understood. Several factors may contribute to the development of cardiac dysfunction in the absence of coronary artery disease in diabetes mellitus. There is growing evidence that excess generation of highly reactive free radicals, largely due to hyperglycemia, causes oxidative stress, which further exacerbates the development and progression of diabetes and its complications. Hyperglycemia-induced oxidative stress is a major risk factor for the development of micro-vascular pathogenesis in the diabetic myocardium, which results in myocardial cell death, hypertrophy, fibrosis, abnormalities of calcium homeostasis and endothelial dysfunction. Diabetes-mediated biochemical changes show cross-interaction and complex interplay culminating in the activation of several intracellular signaling molecules. Diabetic cardiomyopathy is characterized by morphologic and structural changes in the myocardium and coronary vasculature mediated by the activation of various signaling pathways. This review focuses on the oxidative stress and signaling pathways in the pathogenesis of the cardiovascular complications of diabetes, which underlie the development and progression of diabetic cardiomyopathy.

The important role of renin-angiotensin-aldosterone system blockade in the treatment of diabetes-induced cardiomyopathy and nephropathy has been clearly established. The present study examined the effect of angiotensin II type 1 receptor blocker (ARB) losartan on oxidative stress and cardio-renal function in streptozotocin (STZ)-induced diabetic rats. Losartan treatment resulted in improvement of myocardial function and suppressed cardiac and renal fibrosis compared with the diabetic group. Losartan treatment also down-regulated transforming growth factor-beta1 expression and attenuated the increased expression levels of p22(phox) and Nox4. Blood urea nitrogen (BUN) and urinary protein levels were increased significantly in the diabetic group. Losartan treatment significantly reduced proteinuria but not BUN level. Moreover, the elevated level of malondialdehyde in both heart and kidney were significantly reduced in the losartan-treated group compared with the diabetic group. These results provided evidence that oxidative stress plays a major role in diabetic rats induced by STZ, and treatment with the ARB might be beneficial for preventing the development and progression of diabetic disease.

It has been reported that torasemide but not furosemide, may block the renin-angiotensin-aldosterone system and therefore it might attenuate myocardial remodeling accompanied by left ventricular (LV) dysfunction. We therefore compared the therapeutic effects of torasemide, a long-acting loop diuretic, and furosemide, a short-acting one, on the progression of LV remodeling in a rat model of chronic heart failure (CHF) after experimental autoimmune myocarditis (EAM). CHF was elicited in Lewis rats by immunization with porcine cardiac myosin. Twenty-eight days after immunization, rats were treated for 28 days with torasemide, furosemide, or vehicle. We investigated the effects on metabolic and neurohumoral parameters, cardiac fibrosis and remodeling in EAM rats. Diuresis was increased dose dependently by both torasemide and furosemide, showed an equipotent natriuretic effect. The urinary potassium excretion was significantly increased with furosemide in comparison to torasemide. Myocardial functional parameters were significantly improved by torasemide. Conversely, these parameters did not change in rats receiving furosemide. Torasemide suppressed LV fibrosis, myocardial protein levels of transforming growth factor-beta1, collagen III, and aldosterone synthase and improved survival rate to the control level, but furosemide did not. Moreover, both pharmacological interventions significantly elevated plasma angiotensin II and decreased atrial natriuretic peptide in a dose-dependent manner. Our results demonstrate that compared with furosemide, torasemide treatment significantly improved survival rate, LV function and ameliorated the progression of cardiac remodeling in rats with CHF after EAM.

Similar to other neurohormones that are activated in chronic heart failure (CHF), circulating arginine vasopressin (AVP) is elevated in patients with CHF. The precise role of AVP in the pathophysiology of cardiovascular disease is controversial. AVP is a peptide hormone that contributes to water retention and vasoconstriction in CHF through effects on V(2) and V(1a) receptors, respectively. In the present study, the effect of V(2) receptor (V(2)R) blockade using tolvaptan was assessed in a rat model of myosin-induced experimental autoimmune myocarditis. CHF was elicited in Lewis rats by immunization with porcine cardiac myosin, and 28 days after immunization rats were treated for 28 days with oral tolvaptan (3 or 10mg/(kg day)) or vehicle. CHF was characterized by left ventricular remodeling and impaired systolic and diastolic function. Chronic V(2)R blockade increased urine volume and urinary AVP excretion and decreased urine osmolality but had no natriuretic effect, and as a result caused increases in plasma osmolality and sodium. High doses of tolvaptan markedly elevated electrolyte-free water clearance. V(2)R blockade did not activate the renin-angiotensin system, not influence cardiac remodeling, cardiac function, or survival. The upregulation of aquaporin 2 protein in the kidney of CHF rats was inhibited by the administration of V(2)R antagonist. These results suggest that in a rat model of CHF, AVP plays a major role in water retention through the renal V(2)R.

Chymase has been known as a local angiotensin II–generating enzyme in the cardiovascular system in dogs, monkeys, hamsters, and humans; however, recently it was reported that chymase also has various other functions. Therefore, we decided to examine whether the inhibition of chymase improves disease conditions associated with the pathophysiology of dilated cardiomyopathy in rats and its possible mechanism of action as rat chymase is unable to produce angiotensin II. We examined the effect of TY-51469, a novel chymase inhibitor (0.1 mg/kg/day [group CYI-0.1, n = 15] and 1 mg/kg/day [group CYI-1, n = 15]), in myosin-immunized postmyocarditis rats. Another group of myosin-immunized rats was treated with vehicle (group V, n = 15). Age-matched normal rats without immunization (group N, n = 10) were also included in the study. After 4 weeks of treatment, we evaluated cardiac function; area of fibrosis; fibrogenesis; levels of transforming growth factor (TGF)-β1 and collagen III; hypertrophy and its marker, atrial natriuretic peptide (ANP); and mast cell activity. Survival rate and myocardial functions improved dose-dependently with chymase inhibitor treatment after myosin immunization. A reduction in the percent area of myocardial fibrosis, fibrogenesis, myocardial hypertrophy, and mast cell activity along with a reduction in TGF-β1, collagen III, and ANP levels in the myocardium were noted in postmyocarditis rats that received chymase inhibitor treatment. The treatment also decreased myocardial aldosterone synthase levels in those animals. Inhibition of chymase reduces the pathogenesis of postmyocarditis dilated cardiomyopathy and progression to heart failure by preventing the pathological remodeling and residual inflammation in rats.

Background: Although the clustering of a few specific cardiovascular risk factors is known as the metabolic syndrome, sex-specific differences in correlations among risk factors have not been thoroughly examined. Objective: The analysis was undertaken to detect gender differences in correlations among cardio-vascular risk factors. Methods: Correlations among age, body mass index, systolic and diastolic blood pressures, and serum levels of fasting blood sugar (FBS), triglycerides (TG), high- and low-density lipoprotein cholesterol, high-sensitivity C-reactive protein (CRP), and uric acid were analyzed in apparently healthy Japanese men and women with TG Results: Among the 136 men and 136 women examined, the frequency of significant correlations was marginally higher in women than in men: 28/45 correlations versus 17/45 correlations, respectively (P = 0.017). Of a total of 45 possible correlations, 5 were marginally or significantly stronger in women, whereas no correlations among these risk factors were marginally or significantly stronger in men (P = 0.021). These gender differences were considerably attenuated after adjustment for age. However, a significant sex-specific difference was observed in the correlation between TG and rank transformation of CRP, even after adjustment for age (P Conclusions: Correlations among cardiovascular risk factors were marginally stronger in women than in men. These results suggest that the existence of 1 additional risk factor may increase the risk of cardiovascular disease more steeply in women than in men.

Exocrinopathy and pancreatitis-like injury were developed in C57BL/6 (B6) mice infected with LP-BM5 murine leukemia virus, which is known to induce murine acquired immunodeficiency syndrome (MAIDS). The role of chemokines, especially CXCL10/interferon (IFN)-γ-inducible protein 10 (IP-10), a chemokine to attract CXCR3+T helper 1-type CD4+T cells, has not been investigated thoroughly in the pathogenesis of pancreatitis. B6 mice were inoculated intraperitoneally with LP-BM5 and then injected every week with either an antibody against IP-10 or a control antibody. Eight weeks after infection, we analyzed the effect of IP-10 neutralization. Anti-IP-10 antibody treatment did not change the generalized lymphadenopathy and hepatosplenomegaly of mice with MAIDS. The treatment significantly reduced the number of IP-10- and CXCR3-positive cells in the mesenteric lymph nodes (mLNs) but not the phenotypes and gross numbers of cells. In contrast, IP-10 neutralization reduced the number of mononuclear cells infiltrating into the pancreas. Anti-IP-10 antibody treatment did not change the numbers of IFN-γ+and IL10+cells in the mLN but significantly reduced their numbers, especially IFN-γ+and IL-10+CD4+T cells and IFN-γ+Mac-1+cells, in the pancreas. IP-10 neutralization ameliorated the pancreatic lesions of mice with MAIDS probably by blocking the cellular infiltration of CD4+T cells and IFN-γ+Mac-1+cells into the pancreas at least at 8 wk after infection, suggesting that IP-10 and these cells might play a key role in the development of chronic autoimmune pancreatitis.

The aim of the present study was to compare the cardioprotective properties of long-acting calcium channel antagonist pranidipine with amlodipine in rat model of heart failure induced by autoimmune myocarditis. Twenty-eight days after immunization the surviving rats were randomized for the oral administration of low-dose amlodipine (1 mg/kg/day), high-dose amlodipine (5 mg/kg/day), pranidipine (0.3 mg/kg/day) or vehicle (0.5% methylcellulose). After oral administration for 1 month, the animals underwent echocardiography and hemodynamic analysis. Histopathology, immunohistochemistry, and Western immunoblotting were carried out in the heart samples. Both pranidipine and high-dose amlodipine increased survival rate. Although the heart rate did not differ among the four groups, left ventricular end-diastolic pressure was significantly decreased and ±dP/dt was increased in the pranidipine- and high-dose amlodipine-treated rats, but not in low-dose amlodipine-treated rats. In comparison to amlodipine treatment, pranidipine treatment significantly reduced myocyte size and central venous pressure. Furthermore, both pranidipine and high-dose amlodipine treatment significantly reduced myocardial protein levels of atrial natriuretic peptide and inducible nitric oxide synthase, whereas pranidipine only significantly decreased tumor necrosis factor-α, and improved sarcoplasmic reticulum Ca2+ATPase2 protein levels. We conclude that pranidipine ameliorates the progression of left ventricular dysfunction and cardiac remodeling in rats with heart failure after autoimmune myocarditis in a lower dose when compared to amlodipine and which may be a clinically potential therapeutic agent for the treatment of heart failure.

Autoimmune responses and inflammation are involved in the pathogenesis of many cardiovascular diseases. There is compelling evidence that inflammatory mechanisms may contribute to progressive heart failure. Thus, myocardial infiltration of lymphocytes and mononuclear cells, increased expression of pro-inflammatory chemokines and cytokines and circulating autoantibodies are frequently observed in myocarditis and dilated cardiomyopathy (DCM). Experimental autoimmune myocarditis (EAM) in rodents may be elicited by immunization of cardiac myosin and EAM in rats mimics human fulminant myocarditis in the acute phase and human DCM in the chronic phase. Our animal model, EAM was demonstrated to progress into the clinicopathological state similar to DCM in the chronic phase, and was found to be characterized by the enlargement of the heart, dilatation of ventricles, diffuse and extensive myocardial fibrosis, besides being a cellular immunity and inflammation mediated disease. Severity of myocarditis was characterized by increased inflammation, cardiac fibrosis and decreased myocardial performance in rats with DCM. Pharmacological interventions such as angiotensin converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARBs) significantly attenuated the myosin-induced inflammation and cardiac fibrosis and thereby improving myocardial function in rats with DCM. A growing body of evidence shows that ACEI and ARBs contribute to the pharmaceutical management of patients with heart failure mediated by immune and inflammatory response. The purpose of this review is to emphasize the role of inflammation and myocardial fibrosis in rats with DCM after EAM and study the effects of pharmacological interventions such as ACEI, ARBs in the treatment of heart failure through the suppression of inflammatory cytokines and fibrosis.

Anthracyclines, most powerful anticancer agents, suffer from their cardiotoxic effects, which may be due to the induction of oxidative stress. Carvedilol, a third-generation, nonselective β-adrenoreceptor antagonist, possesses both reactive oxygen species (ROS) scavenging and ROS suppressive effects. It showed protective effects against daunorubicin- (DNR-) induced cardiac toxicity by reducing oxidative stress and apoptosis. This study therefore was designed to examine the effects of carvedilol on DNR-induced cardiomyopathic rats, focused on the changes of left ventricular function, cardiac fibrosis, and hypertrophy. Carvedilol increased survival rate, prevented systolic and diastolic dysfunction, and attenuated myocardial fibrosis and hypertrophy. DNR alone treated rats showed upregulated myocardial expression of ANP, PKC-α, OPN, and TGF-β1 and downregulation of GATA-4 in comparison with control, and treatment with carvedilol significantly reversed these changes. The results of the present study add the available evidences on the cardioprotection by carvedilol when associated with anthracyclines and explain the mechanisms underlying the benefits of their coadministration.

Objectives Studies have suggested that angiotensin receptor blockers may exert a protective role towards doxorubicin-induced cardiotoxicity, but they have not been extensively investigated in this area. We therefore investigated whether the co-treatment of telmisartan, an angiotensin (Ang II) type-1 receptor blocker, might offer protection against daunorubicin cardiotoxic properties in rats. Methods Daunorubicin was administered at 3 mg/kg/day every other day for 12 days. Telmisartan was administered orally every day for 12 days. Key findings Daunorubicin-treated rats showed cardiac toxicity, evidenced by worsening cardiac function, evaluated by haemodynamic status and echocardiography, elevation of malondialdehyde level and a decreased level of total glutathione peroxidase activity in the heart tissue. These changes were reversed by treatment with telmisartan. Furthermore, telmisartan also downregulated matrix metalloproteinase-2 expression, attenuated the increased protein expression of p22phox, p47phox, p67phox, nuclear factor kappa B and Nox4 in heart tissue, and reduced oxidative-stress-induced DNA damage, which was evaluated by the expression of 8-hydroxydeoxyguanosine. Moreover, telmisartan reduced the myocardial apoptosis induced by daunorubicin. Conclusions The present study indicates that telmisartan may improve cardiac function by inhibiting the action of Ang II via AT-1R, which reverses oxidative stress and myocardial apoptosis. This suggests a beneficial effect of telmisartan treatment in the prevention of daunorubicin-induced cardiotoxicity.

Experimental autoimmune myocarditis (EAM) is mediated by myocardial infiltration by myosin-specific T-cells secreting inflammatory cytokines. In this study, rat models of EAM were prepared by injection with porcine cardiac myosin. One week after immunization, edaravone was administered intraperitoneally at 3 or 10 mg/kg/day to rats for 2 weeks. Cardiac function was measured by haemodynamic and echocardiographic studies and TUNEL assay was performed. Left ventricular (LV) expression of NADPH oxidase sub-units (p47(phox) and p67(phox)), pro-inflammatory cytokines (TNF-alpha), endoplasmic reticulum (ER) stress signalling proteins (GRP78, caspase-12 and GADD153) and mitogen-activated protein kinase (MAPK) family proteins (phospho-p38 MAPK and phospho-JNK) were measured by western blotting. Edaravone improved LV function in a dose-dependent manner. Central venous pressure was significantly low and LV ejection fraction and fractional shortening was significantly high in edaravone groups compared with those in the vehicle group. In addition, edaravone treatment down-regulated LV expressions of p47(phox), TNF-alpha, GADD153, phospho-p38 MAPK and phospho-JNK. Furthermore, the LV expressions of p67(phox), GRP78, caspase-12 and TUNEL-positive cells of rats with EAM treated with edaravone were significantly low compared with those of the vehicle group. These findings suggest that edaravone ameliorated the progression of EAM by inhibiting oxidative and ER stress and, subsequently, cardiac apoptosis.

The aim was to evaluate the role of the combination of olmesartan, an angiotensin II (Ang II) receptor blocker (ARB), with daunorubicin (DNR) in reducing cardiac toxicity in rats. DNR was administered at a dose of 3 mg/kg/day every other day for 12 days. Olmesartan was administered orally every day for 12 days. Rats treated with DNR alone showed cardiac toxicity as evidenced by worsening cardiac function, elevation of malondialdehyde level in heart tissue and decreased in the level of total glutathione peroxidase activity; treatment with ARB reversed these changes. Furthermore, ARB treatment down-regulated matrix metalloproteinase-2 expression, myocardial expression of Ang II, attenuated the increased protein expressions of p67phox and Nox4 and reduced oxidative stress-induced DNA damage evaluated by expression of 8-hydroxydeoxyguanosine. In conclusion, the result demonstrated that Ang II and oxidative stress play a key role in anthracycline-induced cardiotoxicity and that treatment with ARB will be beneficial against DNR-induced cardiotoxicity.

Arginine vasopressin (AVP) attracted attention as a potentially important neurohormonal mediator of the heart failure (HF) syndrome and hyponatremic states in humans because AVP influences renal handling of free water, vasoconstriction and myocyte biology through activation of V 2 and V 1a receptors. Current research is exploring V 2 - and dual V 1a /V 2 receptor antagonism for the treatment of hyponatremia, as well as for the congestion and edema associated with chronic HF, because vasopressin receptor antagonists might offer benefits in comparison with conventional loop diuretics. The purpose of this review is to update the current status of experimental and clinical studies with available vasopressin receptor antagonists (conivaptan and tolvaptan) and their potential role in the treatment of HF and hyponatremia of multiple causes.

The p38 mitogen-activated protein kinase (MAPK) is activated during heart diseases that might be associated with myocardial damage and cardiac remodeling process. Diabetic cardiomyopathy is associated with increased oxidative stress and inflammation. The purpose of this study was to investigate the role of p38α MAPK after experimental diabetes by using transgenic (TG) mice with cardiac-specific expression of a dominant-negative mutant form of p38α MAPK. The elevation of blood glucose was comparable between the nontransgenic (NTG) and TG mice. The expression of phospho-p38 MAPK and phospho-MAPK-activated protein kinase 2 levels were significantly suppressed in TG mice heart than in NTG mice after diabetes induction. Left ventricular (LV) dimension in systole was smaller, and the percent fractional shortening was higher in diabetic TG mice compared with diabetic NTG mice. In addition, diabetic TG mice had reduced cardiac myocyte diameter, content of cardiac fibrosis, LV tissue expressions of atrial natriuretic peptide, transforming growth factor β1, and collagen III compared with diabetic NTG mice. Moreover, LV expression of NADPH oxidase subunits, p22phox, p67phox, gp91phox, and Nox4, reactive oxygen species and lipid peroxidation levels were significantly increased in diabetic NTG mice, but not in diabetic TG mice. Furthermore, myocardial apoptosis, the number of caspase-3-positive cells, and the downregulation of antiapoptotic protein Bcl-XLwere less in diabetic TG mice compared with diabetic NTG mice. In conclusion, our data establish that p38α MAPK activity is required for cardiac remodeling after diabetes induction and suggest that p38α MAPK may promote cardiomyocyte apoptosis by downregulation of Bcl-XL.

Torasemide is a long-acting loop diuretic that combines the effects of both furosemide and spironolactone. It has been reported that torasemide may block the renin–angiotensin–aldosterone system and therefore it might attenuate myocardial remodeling accompanied by left ventricular dysfunction. However, nothing is known about the effect of torasemide on myocardial remodeling in a rat model in which myosin-induced experimental autoimmune myocarditis might develop into dilated cardiomyopathy. Experimental autoimmune myocarditis was elicited in Lewis rats by immunization with porcine cardiac myosin. Twenty-eight days after immunization, we investigated the effects of torasemide on metabolic and neurohumoral parameters, cardiac fibrosis and remodeling in experimental autoimmune myocarditis rats. Diuresis was increased dose-dependently by torasemide; the urinary potassium and sodium excretion was significantly decreased and increased, respectively. Myocardial functional parameters measured by hemodynamic and echocardiographic studies were significantly improved by torasemide treatment in a dose-dependent manner. The area of fibrosis, myocyte size and the myocardial protein levels of transforming growth factor-beta1, collagen III, and aldosterone synthase were significantly decreased, and the sarcoplasmic reticulum Ca2+ ATPase2 protein level was significantly increased by torasemide treatment. Moreover, the plasma levels of angiotensin II and aldosterone were increased and atrial natriuretic peptide was decreased in a dose-dependent manner. Our results indicate that torasemide treatment significantly improved left ventricular function and ameliorated the progression of cardiac remodeling beyond its renal effects in rats with chronic heart failure after experimental autoimmune myocarditis.

BACKGROUND The purpose of the present study is to examine the agreement of various existing definitions of metabolic syndrome for Japanese. METHODS AND RESULTS One hundred thirty-two apparently healthy men and 147 apparently healthy women underwent testing and diagnosis for metabolic syndrome using 5 different definitions of metabolic syndrome for Japanese, including a newly proposed definition: a modified National Cholesterol Education Program definition replacing abdominal obesity with C-reactive protein. The agreement of these various definitions of metabolic syndrome was studied using an agreement index defined as the number of subjects who met both definitions divided by the number of subjects who met either of the 2 definitions. Agreement indices among these various definitions of metabolic syndrome for Japanese were between 0.19 and 0.6 in men and between 0.31 and 0.89 in women. The average agreement index was 0.41 in men and 0.51 in women, and the overall agreement index was 0.15 in men and 0.21 in women. CONCLUSIONS There was considerable disagreement among various definitions of metabolic syndrome for Japanese. Therefore, diagnosis with this syndrome should not be made until a truly consensual definition of metabolic syndrome can be established.

The role of chemokines, especially CXCL10/interferon-gamma-inducible protein 10 kDa (IP-10), a chemokine to attract CXCR3(+) T-helper 1-type CD4(+) T cells, is largely unknown in the pathophysiology of inflammatory bowel disease; ulcerative colitis and Crohn's disease. The authors have earlier shown that IP-10 neutralization protected mice from acute colitis by protecting crypt epithelial cells of the colon. To investigate the therapeutic effect of neutralization of IP-10 on chronic colitis, an anti-IP-10 antibody was injected into mice with newly established murine AIDS (MAIDS) colitis. Anti-IP-10 antibody treatment reduced the number of colon infiltrating cells when compared to those mice given a control antibody. The treatment made the length of the crypt of the colon greater than control antibody. The number of Ki67(+) proliferating epithelial cells was increased by the anti-IP-10 antibody treatment. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)(+) apoptotic cells were observed in the epithelial cells of the luminal tops of crypts in control MAIDS colitis, whereas TUNEL(+) apoptotic epithelial cells were rarely observed with anti-IP-10 antibody treatment. In conclusion, blockade of IP-10 attenuated MAIDS colitis through blocking cellular trafficking and protecting intestinal epithelial cells, suggesting that IP-10 plays a key role in the development of inflammatory bowel disease as well as in chronic experimental colitis.

Background C-reactive protein (CRP) independently predicts cardiovascular disease (CVD) and is considered to be part of metabolic syndrome (MS). The concentration of CRP are proposed to be 3.0 mg/L as high risk for CVD in Western society. Methods and Results Apparently healthy 179 men and 166 women were categorized with modified National Cholesterol Education Program Adult Treatment Panel III criteria (body mass index ≥25 in place of abdominal obesity) for defining MS. The cut-off points of CRP were evaluated for both MS defined by impaired fasting glucose criteria of ≥110 mg/dl (MS110) and ≥100 mg/dl (MS100), separately by sex. The optimal cut-off point of CRP was 0.65 mg/L in all subgroups. The sensitivity and specificity of this CRP value for male MS100, female MS100, male MS110, and female MS110 were 0.650 and 0.626, 1.000 and 0.771, 0.739 and 0.609, and 1.000 and 0.756, respectively. Conclusions The optimal cut-off point of CRP for MS might be 0.65 mg/L in Japan and this value can be useful in routine clinical practice and studies on MS. (Circ J 2006; 70: 384 - 388)

Background: Anthracyclines have been reported to induce cardiotoxicity through mechanisms involving formation of advanced glycation end-products (AGEs), including pentosidine and Nє-(carboxymethyl) lysine (CML). We investigated the potential utility of telmisartan (TML), an angiotensin II receptor antagonists (ARB) on anthracycline-induced cardiotoxicity.Methods: Three groups of Sprague-Dawley rats were treated as follows: The first group received daunorubicin (DNR) 3 mg/kgBW every alternating day to reach a cumulative dose of 9 mg/kg DNR . The second group received DNR plus TLM at a dose10 mg/kgBW, by oral gavage for 6 weeks, and the third group served as control group (CTL) which only received vehicle of DNR. Mean blood pressure (MBP) peak left ventricular pressure (LVP), LV end-diastolic pressure (LVEDP), and intra-ventricular contractility (±dP/dt) were recorded by using Powerlab instrumentation. Ejection fraction (EF), and fractional shortening (FS) were measured by echocardiography. Expression of receptor of AGE (RAGE), pentosidine and CML were measured by immunohistochemistry and Western blot in LV tissue.Results: DNR treatment was associated with significant weakening of some hemodynamic parameters which couldbe reversed by TML (LVP: 124.3 ± 6.0; 111 ± 7; and 115.1 ± 5.4 mmHg, respectively in CTL, DNR and DNR-TLM groups; LVEDP: 7.5 ± 0.9; 10.7 ± 0.3; 8.7 ± 0.4 mmHg, respectively; +dP/dt: 6813 ± 541; 4800 ± 345; 5950 ± 398 mmHg/s, respectively). The same phenomenons were also observed on echocardiographic parameters (EF: 78.9 ± 1.8; 59.6 ± 1.4; 76.2 ± 2.75 %, resepectively; FS: 42.8 ± 1.7; 29.1 ± 1.3; 41 ± 2.7 %) respectively. Expression of RAGE as well as pentosidine and CML were increased in DNR-rats. TML treatment ameliorated these changes.Conclusion: These results suggested the role of AGE formation in DNR-induced cardiotoxicity and telmisartan could inhibit the progression of cardiac toxicity at least in part by reduction RAGE expressiom. (Med J Indones 2011; 20:255-62)Keywords: advanced glycation end product, anthracyline, cardiotoxicity, daunorubicin, telmisartan

Studies have demonstrated that angiotensin II has been involved in immune and inflammatory responses which might contribute to the pathogenesis of immune-mediated diseases. Recent evidence suggests that oxidative stress may play a role in myocarditis. Here, we investigated whether olmesartan, an AT(1)R antagonist protects against experimental autoimmune myocarditis (EAM) by suppression of oxidative stress, endoplasmic reticulum (ER) stress and inflammatory cytokines. EAM was induced in Lewis rats by immunization with porcine cardiac myosin, were divided into two groups and treated with either olmesartan (10 mg/kg/day) or vehicle for a period of 21 days. Myocardial functional parameters measured by hemodynamic and echocardiographic analyses were significantly improved by the treatment with olmesartan compared with those of vehicle-treated rats. Treatment with olmesartan attenuated the myocardial mRNA expressions of proinflammatory cytokines, [Interleukin (IL)-1β, monocyte chemoattractant protein-1, tumor necrosis factor-α and interferon-γ)] and the protein expression of tumor necrosis factor-α compared with that of vehicle-treated rats. Myocardial protein expressions of AT(1)R, NADPH oxidase subunits (p47phox, p67phox, gp91phox) and the expression of markers of oxidative stress (3-nitrotyrosine and 4-hydroxy-2-nonenal), and the cardiac apoptosis were also significantly decreased by the treatment with olmesartan compared with those of vehicle-treated rats. Furthermore, olmesartan treatment down-regulated the myocardial expressions of glucose regulated protein-78, growth arrest and DNA damage-inducible gene, caspase-12, phospho-p38 mitogen-activated protein kinase (MAPK) and phospho-JNK. These findings suggest that olmesartan protects against EAM in rats, at least in part via suppression of oxidative stress, ER stress and inflammatory cytokines.

Background Chronic inflammation plays an important role in the progression of diabetic nephropathy (DN) and that the infiltration of macrophages in glomerulus has been implicated in the development of glomerular injury. We hypothesized that the plant polyphenolic compound curcumin, which is known to exert potent anti-inflammatory effect, would ameliorate macrophage infiltration in streptozotocin (STZ)-induced diabetic rats. Methods Diabetes was induced with STZ (55 mg/kg) by intraperitoneal injection in rats. Three weeks after STZ injection, rats were divided into three groups, namely, control, diabetic, and diabetic treated with curcumin at 100 mg/kg/day, p.o., for 8 weeks. The rats were sacrificed 11 weeks after induction of diabetes. The excised kidney was used to assess macrophage infiltration and expression of various inflammatory markers. Results At 11 weeks after STZ injection, diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, increased blood glucose, blood urea nitrogen and proteinuria, along with marked reduction in the body weight. All of these abnormalities were significantly reversed by curcumin. Hyperglycemia induced the degradation of IκBα and NF-κB activation and as a result increased infiltration of macrophages (52%) as well as increased proinflammatory cytokines: TNF-α and IL-1β. Curcumin treatment significantly reduced macrophage infiltration in the kidneys of diabetic rats, suppressed the expression of above proinflammatory cytokines and degradation of IκBα. In addition, curcumin treatment also markedly decreased ICAM-1, MCP-1 and TGF-β1 protein expression. Moreover, at nuclear level curcumin inhibited the NF-κB activity. Conclusion Our results suggested that curcumin treatment protect against the development of DN in rats by reducing macrophage infiltration through the inhibition of NF-κB activation in STZ-induced diabetic rats.