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Background: Diabetes mellitus type 2 (DM2) is associated with high platelet reactivity both in patients who do not receive antiplatelet drugs and in those treated with acetylsalicylic acid (ASA). The pathomechanism of this phenomenon has not been fully understood., Aim: 1. To evaluate variability of platelet reactivity in patients with DM2 treated with oral antidiabetic drugs and receiving chronic ASA therapy. 2. To identify independent predictors of high platelet reactivity during ASA therapy in patients with DM2., Methods: We studied 171 patients with DM2 treated with oral antidiabetic drugs and receiving long-term treatment with 75 mg of ASA daily, selected among the participants of the prospective AVOCADO study. Platelet function was simultaneously evaluated using 4 methods: 1. measurement of serum thromboxane B2 (TXB2) concentration; 2. measurement of urinary 11-dehydrothromboxane B2 (11-dhTXB2) concentration; 3. VerifyNow® automated analyser; 4. PFA-100® automated analyser.High platelet reactivity was defined as at least 3 of the following criteria: 1. serum TXB2 concentration in the upper quartile;2. urinary 11-dhTXB2 concentration in the upper quartile; 3. value ≥ 550 aspirin reaction units (ARU) by VerifyNow®;4. collagen-epinephrine closure time (CEPI-CT) below median of readings other than 300 s by PFA-100®. In all patients, DM2 control was evaluated, insulin resistance was measured using HOMA-IR, and routine laboratory tests were performed, including full blood count, renal function parameters, and inflammation markers., Results: Mean patient age was 67.8 years, and median duration of DM2 was 5 years. We found poor agreement between different tests of platelet function. ARU ≥ 550 (VerifyNow®) was found in 14.0% of patients, and CEPI-CT below median of readings other than 300 s (PFA-100®) was found in 32.8% of patients. Our criteria of high platelet reactivity were met by 9.9% of patients. In multivariate logistic regression analysis, independent predictors of high platelet reactivity despite ASA therapy included chronic heart failure, current smoking, and higher leukocyte count., Conclusions: 1. Patients with DM2 are characterised by large variability of platelet reactivity, with little agreement between various methods. 2. Smoking, chronic heart failure, and subclinical inflammation may be associated with high platelet reactivity in patients with DM2 treated with ASA.

Aims/hypothesis: Diabetic cardiomyopathy is characterised by diastolic dysfunction, oxidative stress, fibrosis, apoptosis and pathological cardiomyocyte hypertrophy. Phosphoinositide 3-kinase (PI3K)(p110α) is a cardioprotective kinase, but its role in the diabetic heart is unknown. The aim of this study was to assess whether PI3K(p110α) plays a critical role in the induction of diabetic cardiomyopathy, and whether increasing PI3K(p110α) activity in the heart can prevent the development of cardiac dysfunction in a setting of diabetes., Methods: Type 1 diabetes was induced with streptozotocin in adult male cardiac-specific transgenic mice with increased PI3K(p110α) activity (constitutively active PI3K [p110α], caPI3K] or decreased PI3K(p110α) activity (dominant-negative PI3K [p110α], dnPI3K) and non-transgenic (Ntg) mice for 12 weeks. Cardiac function, histological and molecular analyses were performed., Results: Diabetic Ntg mice displayed diastolic dysfunction and increased cardiomyocyte size, expression of atrial and B-type natriuretic peptides (Anp, Bnp), fibrosis and apoptosis, as well as increased superoxide generation and increased protein kinase C β2 (PKCβ2), p22 ( phox ) and apoptosis signal-regulating kinase 1 (Ask1) expression. Diabetic dnPI3K mice displayed an exaggerated cardiomyopathy phenotype compared with diabetic Ntg mice. In contrast, diabetic caPI3K mice were protected against diastolic dysfunction, pathological cardiomyocyte hypertrophy, fibrosis and apoptosis. Protection in diabetic caPI3K mice was associated with attenuation of left ventricular superoxide generation, attenuated Anp, Bnp, PKCβ2, Ask1 and p22 ( phox ) expression, and elevated AKT. Further, in cardiomyocyte-like cells, increased PI3K(p110α) activity suppressed high glucose-induced superoxide generation and enhanced mitochondrial function., Conclusions/interpretation: These results demonstrate that reduced PI3K activity accelerates the development of diabetic cardiomyopathy, and that enhanced PI3K(p110α) activity can prevent adverse cardiac remodelling and dysfunction in a setting of diabetes.

An increased cardiac fatty acid supply and increased sarcolemmal presence of the long-chain fatty acid transporter CD36 are associated with and contribute to impaired cardiac insulin sensitivity and function. In the present study we aimed at preventing the development of insulin resistance and contractile dysfunction in cardiomyocytes by blocking CD36-mediated palmitate uptake. Insulin resistance and contractile dysfunction were induced in primary cardiomyocytes by 48 h incubation in media containing either 100 nM insulin (high insulin; HI) or 200 μM palmitate (high palmitate; HP). Under both culture conditions, insulin-stimulated glucose uptake and Akt phosphorylation were abrogated or markedly reduced. Furthermore, cardiomyocytes cultured in each medium displayed elevated sarcolemmal CD36 content, increased basal palmitate uptake, lipid accumulation and decreased sarcomere shortening. Immunochemical CD36 inhibition enhanced basal glucose uptake and prevented elevated basal palmitate uptake, triacylglycerol accumulation and contractile dysfunction in cardiomyocytes cultured in either medium. Additionally, CD36 inhibition prevented loss of insulin signalling in cells cultured in HP, but not in HI medium. In conclusion, CD36 inhibition prevents lipid accumulation and lipid-induced contractile dysfunction in cardiomyocytes, but probably independently of effects on insulin signalling. Nonetheless, pharmacological CD36 inhibition may be considered as a treatment strategy to counteract impaired functioning of the lipid-loaded heart.

The development of diabetic cardiomyopathy is accompanied with a high membrane-bound protein kinase C (PKC) levels. Curcumin is a naturally occurring compound which is known to inhibit PKC activity. However, the effects of curcumin on ameliorating diabetic cardiomyopathy are still undefined. We evaluated whether curcumin treatment is associated with the modulation of PKC-α and -β₂-mitogen-activated protein kinase (MAPK) pathway in experimental diabetic cardiomyopathy. Diabetes was induced in male Sprague-Dawley rats by streptozotocin (STZ). Curcumin (100mg/kg/day) was started three weeks after STZ injection and was given for 8 weeks. We demonstrate that curcumin significantly prevented diabetes-induced translocation of PKC-α and -β2 to membranous fraction and diabetes-induced increased phosphorylation of p38MAPK and extracellular regulated-signal kinase (ERK)1/2 in left ventricular tissues of diabetic rats. Curcumin treatment also markedly decreased NAD(P)H oxidase subunits (p67phox, p22phox, gp91phox), growth factors (transforming growth factor-β, osteopontin) and myocyte enhancer factor-2 protein expression as well as inhibited NF-κB activity at nuclear level. Furthermore, curcumin decreased the mRNA expression of transcriptional coactivator p300 and atrial natriuretic peptide, decreased accumulation of ECM protein and reversed the increment of superoxide production in left ventricular tissues, as evidenced by dihydroethidium staining. It is also significantly lowered plasma glucose and attenuated oxidative stress, as determined by lipid peroxidation and activity of anti-oxidant enzyme, and as a result attenuated cardiomyocyte hypertrophy, myocardial fibrosis and left ventricular dysfunction. Taken together, it is suggested that curcumin by inhibiting PKC-α and -β₂-MAPK pathway may be useful as an adjuvant therapy for the prevention of diabetic cardiomyopathy., (Copyright © 2012. Published by Elsevier B.V.)

Diabetic cardiomyopathy is characterized, in part, by calcium handling imbalances associated with ventricular dysfunction. The cardiac Na(+)/Ca(2+) exchanger 1 (NCX1) has been implicated as a compensatory mechanism in response to reduced contractility in the heart; however, its role in diabetic cardiomyopathy remains unknown. We aimed to fully characterize the Akita(ins2) murine model of type 1 diabetes through assessing cardiac function and NCX1 regulation. The CXCL12/CXCR4 chemokine axis is well described in its cardioprotective effects via progenitor cell recruitment postacute myocardial infarction; however, it also functions in regulating calcium dependent processes in the cardiac myocyte. We therefore investigated the potential impact of CXCR4 in diabetic cardiomyopathy. Cardiac performance in the Akita(ins2) mouse was monitored using echocardiography and in vivo pressure-volume analysis. The Akita(ins2) mouse is protected against ventricular systolic failure evident at both 5 and 12 mo of age. However, the preserved contractility was associated with a decreased sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2a)/phospholamban ratio and increased NCX1 content. Direct myocardial injection of adenovirus encoding anti-sense NCX1 significantly decreased NCX1 expression and induced systolic failure in the Akita(ins2) mouse. CXCL12 and CXCR4 were both upregulated in the Akita(ins2) heart, along with an increase in IκB-α and NF-κB p65 phosphorylation. We demonstrated that CXCR4 activation upregulates NCX1 expression through a NF-κB-dependent signaling pathway in the cardiac myocyte. In conclusion, the Akita(ins2) type 1 diabetic model is protected against systolic failure due to increased NCX1 expression. In addition, our studies reveal a novel role of CXCR4 in the diabetic heart by regulating NCX1 expression via a NF-κB-dependent mechanism.

Background: Xanthine oxidase-derived superoxide production and oxidative stress contribute to the development of diabetic complications including diabetic cardiomyopathy. We hypothesized that xanthine oxidase-inhibitor allopurinol (ALP) may decrease hyperglycemia-induced oxidative stress, ameliorate cardiomyocyte hypertrophy and fibrosis, and attenuate the development of left ventricle (LV) diastolic dysfunction in rats with streptozotocin (STZ)-induced diabetes., Methods: Control Sprague Dawley (C) or streptozotocin-induced diabetic (D) rats were either untreated or treated with allopurinol (100 mg/kg/day) for 4 weeks starting at 1 week after streptozotocin injection. Free 15-F2t-isoprostane, a specific indicator of oxidative stress was measured by enzymatic immunoassay. The cardiomyocyte cross-sectional area was assessed by hematoxylin and eosin-stained paraffin-embedded sections of LVs. Myocardial collagens I and III were assessed by immunol histochemistry and Western blotting. Echocardiography was performed to characterize cardiac structure and function., Results: In diabetic rats, both plasma and cardiac tissue levels of free 15-F2t-isoprostane were increased (p < 0.05 vs. control), accompanied with significant increase (p < 0.05 vs. control) in cross-section area and myocardial collagen deposition of LV cardiomyocyte. Echocardiography in diabetic rats showed that LV weight/body weight ratio was significantly higher than in control rats, whereas the levels of LV end-diastolic volume and stroke volume were decreased (all p < 0.05 diabetic vs. control). All these changes were either attenuated or prevented by allopurinol. In addition, LV ejection fraction in diabetic rats treated with allopurinol was higher than that in untreated diabetic rats (p < 0.05)., Conclusion: Allopurinol can attenuate hyperglycemia-induced oxidative stress, ameliorate cardiomyocyte hypertrophy and fibrosis and subsequently prevent left ventricular dysfunction in early diabetes., (Copyright © 2012 John Wiley & Sons, Ltd.)

Objective: To investigate the protective effects of terpenes from fructus corni (TFC) on diabetic cardiomyopathy (DCM)., Methods: Diabetes was produced by a single injection of alloxan (220 mg/kg, i.p.) in mice. The fasting blood glucose of mice were tested 15 days later and that greater than 13.9 mmol/L were regarded as the diabetic mice which were divided randomly into the model and TFC groups. TFC dissolved by physiological saline (P.O, 80 mg/kg) was administrated to the TFC group for successive 8 weeks since the 15th day., Results: Compared to the control group, the weight index increased significantly. The level of superoxide dismutase (SOD) was markedly decreased and malondialdehyde(MDA), the inflammatory factors (TNF-alpha, IL-6) were obviously increased in myocardium. The histopathological examination suggested that myocardial cells disarranged, swelling and the intercellular space increased in model group. It also showed the infiltration of inflammatory cells and fibroblasts in TFC group. The above change was improved significantly., Conclusion: TFC ameliorated the alterations of cardiomyopathy in diabetic mice induced by alloxan. the mechanism might be related to decrease blood glucose, antioxidative stress and inflammatory factors.

Background: Alpha-lipoic acid (ALA), a naturally occurring compound, exerts powerful protective effects in various cardiovascular disease models. However, its role in protecting against diabetic cardiomyopathy (DCM) has not been elucidated. In this study, we have investigated the effects of ALA on cardiac dysfunction, mitochondrial oxidative stress (MOS), extracellular matrix (ECM) remodeling and interrelated signaling pathways in a diabetic rat model., Methods: Diabetes was induced in rats by I.V. injection of streptozotocin (STZ) at 45 mg/kg. The animals were randomly divided into 4 groups: normal groups with or without ALA treatment, and diabetes groups with or without ALA treatment. All studies were carried out 11 weeks after induction of diabetes. Cardiac catheterization was performed to evaluate cardiac function. Mitochondrial oxidative biochemical parameters were measured by spectophotometeric assays. Extracellular matrix content (total collagen, type I and III collagen) was assessed by staining with Sirius Red. Gelatinolytic activity of Pro- and active matrix metalloproteinase-2 (MMP-2) levels were analyzed by a zymogram. Cardiac fibroblasts differentiation to myofibroblasts was evaluated by Western blot measuring smooth muscle actin (α-SMA) and transforming growth factor-β (TGF-β). Key components of underlying signaling pathways including the phosphorylation of c-Jun N-terminal kinase (JNK), p38 MAPK and ERK were also assayed by Western blot., Results: DCM was successfully induced by the injection of STZ as evidenced by abnormal heart mass and cardiac function, as well as the imbalance of ECM homeostasis. After administration of ALA, left ventricular dysfunction greatly improved; interstitial fibrosis also notably ameliorated indicated by decreased collagen deposition, ECM synthesis as well as enhanced ECM degradation. To further assess the underlying mechanism of improved DCM by ALA, redox status and cardiac remodeling associated signaling pathway components were evaluated. It was shown that redox homeostasis was disturbed and MAPK signaling pathway components activated in STZ-induced DCM animals. While ALA treatment favorably shifted redox homeostasis and suppressed JNK and p38 MAPK activation., Conclusions: These results, coupled with the excellent safety and tolerability profile of ALA in humans, demonstrate that ALA may have therapeutic potential in the treatment of DCM by attenuating MOS, ECM remodeling and JNK, p38 MAPK activation.

Inhibition of Rho kinase (ROCK) has been shown to improve diabetic-related disorders. In this study, the cardio-protective effects and potential mechanisms of fasudil, a selective ROCK inhibitor, on diabetic cardiomyopathy were investigated in a streptozotocin (STZ)-induced diabetic rat model. Eight weeks after diabetes was induced by a single tail vein injection of 60 mg/kg STZ, rats were administered long-term fasudil or captopril as a control over a four-week period. Similar to the effect of captopril, fasudil treatment significantly protected against STZ-induced hemodynamic, histopathologic changes and decreased serum lactate dehydrogenase and creatine phosphokinase. Moreover, fasudil significantly down-regulated ROCK I mRNA expression and ROCK activity, reduced cardiac collagen deposition, and decreased the incidence of apoptosis and ratio of Bax/Bcl-2 protein expression. Additionally, fasudil potently elevated superoxide dismutase activity and suppressed the extent of lipid peroxidation in sera and hearts of diabetic rats. Our findings indicated that long-term treatment with fasudil could improve cardiac dysfunction, attenuate myocardial injury and prevent pathological changes in a rat model of diabetic cardiomyopathy. These effects could be attributed to regulation of antioxidative activities, suppression of myocardial hypertrophy, apoptosis, fibrosis and subsequent cardiac remodeling. These results may help to expand the clinical application of fasudil for diabetic cardiomyopathy., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Aims: Data on glucose and cardiovascular disease (CVD) risk factor control among persons with type 2 diabetes mellitus (DM) according to insulin treatment status are lacking. We examined DM control, risk factors, and comorbidities among U.S. persons according to insulin treatment status., Methods: In the U.S. National Health and Nutrition Examination Surveys 2003-2006, we examined in 10,637 adults aged ≥30 with type 2 DM the extent of control of A1c, LDL-C, HDL-C, triglycerides, and blood pressure (BP) and composite goal attainment by insulin use status., Results: 6.6% (n=889, projected to 14.3 million) had type 2 DM; of these, 22.9% were insulin users and 57.2% were treated only by other diabetes medications. Overall, 58.2% had an A1c<7% (53 mmol/mol) (insulin users 33.1%, non-insulin treated 66.1%, and 77.9% of those not on medication, p<0.0001). Overall, 44.2% were at a BP goal of <130/80 mmHg, 43.8% had an LDL-C<100 mg/dl (2.6 mmol/L), and 13.9% a BMI<25 kg/m(2). Only 10.2% were simultaneously at A1c, LDL, and BP goals (5.4% of those on insulin)., Conclusions: U.S. adults with type 2 DM, especially those treated with insulin remain inadequately controlled for A1c and CVD risk factors and have a high prevalence of comorbidities., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Mitochondrial aldehyde dehydrogenase (ALDH2) displays some promise in the protection against cardiovascular diseases although its role in diabetes has not been elucidated., Methods: This study was designed to evaluate the impact of ALDH2 on streptozotocin-induced diabetic cardiomyopathy. Friendly virus B(FVB) and ALDH2 transgenic mice were treated with streptozotocin (intraperitoneal injection of 200 mg/kg) to induce diabetes., Results: Echocardiographic evaluation revealed reduced fractional shortening, increased end-systolic and -diastolic diameter, and decreased wall thickness in streptozotocin-treated FVB mice. Streptozotocin led to a reduced respiratory exchange ratio; myocardial apoptosis and mitochondrial damage; cardiomyocyte contractile and intracellular Ca2+ defects, including depressed peak shortening and maximal velocity of shortening and relengthening; prolonged duration of shortening and relengthening; and dampened intracellular Ca2+ rise and clearance. Western blot analysis revealed disrupted phosphorylation of Akt, glycogen synthase kinase-3β and Foxo3a (but not mammalian target of rapamycin), elevated PTEN phosphorylation and downregulated expression of mitochondrial proteins, peroxisome proliferator-activated receptor γ coactivator 1α and UCP-2. Intriguingly, ALDH2 attenuated or ablated streptozotocin-induced echocardiographic, mitochondrial, apoptotic and myocardial contractile and intracellular Ca2+ anomalies as well as changes in the phosphorylation of Akt, glycogen synthase kinase-3β, Foxo3a and phosphatase and tensin homologue on chromosome ten, despite persistent hyperglycemia and a low respiratory exchange ratio. In vitro data revealed that the ALDH2 activator Alda-1 and glycogen synthase kinase-3β inhibition protected against high glucose-induced mitochondrial and mechanical anomalies, the effect of which was cancelled by mitochondrial uncoupling., Conclusions: In summary, our data revealed that ALDH2 acted against diabetes-induced cardiac contractile and intracellular Ca2+ dysregulation, possibly through regulation of apoptosis, glycogen synthase kinase-3β activation and mitochondrial function independent of the global metabolic profile.

Oxidative stress plays critical roles in the development of diabetic cardiovascular complications, including myocardial hypertrophy. The β isoform of PKC (protein kinase C) is preferentially overexpressed in the myocardium of diabetic subjects accompanied with increased activation of the pro-oxidant enzyme NADPH oxidase, which may exacerbate oxidative stress. We hypothesized that myocardial PKCβ is a major upstream mediator of oxidative stress in diabetes and that PKCβ inhibition can attenuate myocardial hypertrophy and dysfunction. Control or streptozotocin-induced diabetic rats were treated with the selective PKCβ inhibitor RBX (ruboxistaurin; 1 mg/kg of body weight per day) or the antioxidant NAC (N-acetylcysteine) for 4 weeks. LV (left ventricular) dimensions and functions were detected by echocardiography. 15-F2t-isoprostane (a specific index of oxidative stress) and myocardial activities of superoxide dismutase as well as protein levels of NADPH oxidase were assessed by immunoassay or Western blotting. Echocardiography revealed that the LV mass/body weight ratio was significantly increased in diabetic rats (P<0.01 compared with the control group) in parallel with the impaired LV relaxation. A significant increase in cardiomyocyte cross-sectional area was observed in diabetic rats accompanied by an increased production of O2- (superoxide anion) and 15-F2t-isoprostane (all P<0.05 compared with the control group). RBX normalized these changes with concomitant inhibition of PKCβ2 activation and prevention of NADPH oxidase subunit p67phox membrane translocation and p22phox overexpression. The effects of RBX were comparable with that of NAC, except that NAC was inferior to RBX in attenuating cardiac dysfunction. It is concluded that RBX can ameliorate myocardial hypertrophy and dysfunction in diabetes, which may represent a novel therapy in the prevention of diabetic cardiovascular complications.

Heart failure (HF) occurs when the adaptation mechanisms of the heart fail to compensate for stress factors, such as pressure overload, myocardial infarction, inflammation, diabetes, and cardiotoxic drugs, with subsequent ventricular hypertrophy, fibrosis, myocardial dysfunction, and chamber dilatation. Oxidative stress, defined as an imbalance between reactive oxygen species (ROS) generation and the capacity of antioxidant defense systems, has been authenticated as a pivotal player in the cardiopathogenesis of the various HF subtypes. The family of NADPH oxidases has been investigated as a key enzymatic source of ROS in the pathogenesis of HF. In this review, we discuss the importance of NADPH oxidase-dependent ROS generation in the various subtypes of HF and its implications. A better understanding of the pathogenic roles of NADPH oxidases in the failing heart is likely to provide novel therapeutic strategies for the prevention and treatment of HF., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Diabetes, stress, pharmaceuticals, surgery, and physical trauma can lead to hyperglycemic conditions. A consistent relationship has been found between chronic inflammation and the cardiovascular complications of hyperglycemia. We hypothesized that cardiomyopathy and vasculopathy resulting from acute hyperglycemia are dependent on mannose-binding lectin (MBL) and lectin complement pathway activation. Hyperglycemia was induced in wild-type (WT) C57BL/6 and MBL-null mice after streptozotocin administration. Echocardiographic data and tissue samples were collected after 4, 7, or 14 days of acute hyperglycemia. Hyperglycemic WT mice demonstrated dilated cardiomyopathy with significantly increased short and long axis area measurements during systole and diastole compared to hyperglycemic MBL-null mice. The EC(50) for acetylcholine-induced relaxation of mesenteric arterioles in WT mice after 4 days of hyperglycemia demonstrated a significant loss of nitric oxide-mediated relaxation compared to normoglycemic WT or hyperglycemic MBL-null mice. Myocardial histochemistry and Western blot analysis revealed a significant influx of macrophages, altered morphology, and increased elastin and collagen deposition in hyperglycemic WT hearts compared to MBL-null hearts. Serum transforming growth factor-β1 levels were significantly lower in hyperglycemic MBL-null compared to WT mice, suggesting decreased profibrotic signaling. Together, these data suggest that MBL and the lectin complement pathway play a significant role in vascular dysfunction and cardiomyopathy after acute hyperglycemia., (Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Background: Obesity-related diabetes mellitus leads to increased myocardial uptake and oxidation of fatty acids, resulting in a form of cardiac dysfunction referred to as lipotoxic cardiomyopathy. We have shown previously that Astragalus polysaccharides (APS) administration was sufficient to improve the systemic metabolic disorder and cardiac dysfunction in diabetic models., Methodology/principal Findings: To investigate the precise role of APS therapy in the pathogenesis of myocardial lipotoxity in diabetes, db/db diabetic mice and myosin heavy chain (MHC)- peroxisome proliferator-activated receptor (PPAR) α mice were characterized and administrated with or without APS with C57 wide- type mice as normal control. APS treatment strikingly improved the myocyte triacylglyceride accumulation and cardiac dysfunction in both db/db mice and MHC-PPARα mice, with the normalization of energy metabolic derangements in both db/db diabetic hearts and MHC-PPARα hearts. Consistently, the activation of PPARα target genes involved in myocardial fatty acid uptake and oxidation in both db/db diabetic hearts and MHC-PPARα hearts was reciprocally repressed by APS administration, while PPARα-mediated suppression of genes involved in glucose utilization of both diabetic hearts and MHC-PPARα hearts was reversed by treatment with APS., Conclusions: We conclude that APS therapy could prevent the development of diabetic cardiomyopathy through a mechanism mainly dependent on the cardiac PPARα-mediated regulatory pathways.

Reactive oxygen species (ROS) play important roles in the occurrence and development in diabetic cardiomyopathy (DC). Ferulic acid is one of the ubiquitous compounds in diet. Sodium ferulate (SF) is its sodium salt. SF has potent free radical scavenging activity and can effectively scavenge ROS. The study investigated the effect of SF on cardioprotection in diabetic rats. The diabetic rats induced by streptozotocin (STZ) were treated with SF (110mg/kg) by gavage per day for 12 weeks. Results showed that the levels of nitric oxide (NO) and superoxide dismutase (SOD) activity in plasma and myocardium in SF-treated group were significantly higher than those in diabetic control group. The levels of malondialdehyde (MDA) in plasma and myocardium in SF-treated group were significantly lower than those in diabetic control group. Expression of connective tissue growth factor (CTGF) in myocardium in SF-treated group was apparently lower than that in diabetic control group. Compared with normal control group, electron micrographs of myocardium in diabetic control group showed apparently abnormality, while that was significantly ameliorated in SF-treated group. The study demonstrated that SF has a cardioprotective effect via increasing SOD activity and NO levels in plasma and myocardium, inhibiting oxidative stress in plasma and myocardium, and inhibiting the expression of CTGF in myocardium in diabetes rats.

Diabetes is a cause of cardiac dysfunction, reduced myocardial perfusion, and ultimately heart failure. Nerve growth factor (NGF) exerts protective effects on the cardiovascular system. This study investigated whether NGF gene transfer can prevent diabetic cardiomyopathy in mice. We worked with mice with streptozotocin-induced type 1 diabetes and with nondiabetic control mice. After having established that diabetes reduces cardiac NGF mRNA expression, we tested NGF gene therapies with adeno-associated viral vectors (AAVs) for the capacity to protect the diabetic mouse heart. To this aim, after 2 weeks of diabetes, cardiac expression of human NGF or β-Gal (control) genes was induced by either intramyocardial injection of AAV serotype 2 (AAV2) or systemic delivery of AAV serotype 9 (AAV9). Nondiabetic mice were given AAV2-β-Gal or AAV9-β-Gal. We found that the diabetic mice receiving NGF gene transfer via either AAV2 or AAV9 were spared the progressive deterioration of cardiac function and left ventricular chamber dilatation observed in β-Gal-injected diabetic mice. Moreover, they were additionally protected from myocardial microvascular rarefaction, hypoperfusion, increased deposition of interstitial fibrosis, and increased apoptosis of endothelial cells and cardiomyocytes, which afflicted the β-Gal-injected diabetic control mice. Our data suggest therapeutic potential of NGF for the prevention of cardiomyopathy in diabetic subjects.

Diabetic cardiomyopathy and nephropathy are two major causes of death of patients with diabetes. Extra generation of reactive oxygen species (ROS), induced by hyperglycemia, is considered as the main reason for the development of these diabetic complications. Transcription factor, NFE2-related factor 2 (Nrf2), is a master regulator of cellular detoxification response and redox status, and also provides a protective action from various oxidative stresses and damages. Recently we have demonstrated its important role in determining the susceptibility of cells or tissues to diabetes-induced oxidative stress and/or damage. Therefore, this review will specifically summarize the information available regarding the effect of Nrf2 on the diabetic complications with a focus on diabetic cardiomyopathy and nephropathy. Given the feature that Nrf2 is easily induced by several compounds, we also discussed the role of different Nrf2 activators in the prevention or therapy of various diabetic complications. These findings suggest that Nrf2 has a potential application in the clinic setting for diabetic patients in the short future.

We have previously shown that chronic treatment with propranolol had beneficial effects on heart function in rats during increasing-age in a gender-dependent manner. Herein, we hypothesize that propranolol would improve cardiac function in diabetic cardiomyopathy and investigated the benefits of chronic oral administration of propranolol on the parameters of Ca(2+) signaling in the heart of streptozotocin-diabetic rats. Male diabetic rats received propranolol (25 mg/kg, daily) for 12 weeks, 1 week after diabetes induction. Treatment of the diabetic rats with propranolol did not produce a hypoglycaemic effect whereas it attenuated the increased cell size. Basal and β-agonist response levels of left ventricular developed pressure were significantly higher in propranolol-treated diabetic rats relative to untreated diabetics while left ventricular end diastolic pressure of the treated diabetics was comparable to the controls. Propranolol treatment normalized also the prolongation of the action potential in papillary muscles from the diabetic rat hearts. This treatment attenuated the parameters of Ca(2+) transients, depressed Ca(2+) loading of the sarcoplasmic reticulum, and of the basal intracellular Ca(2+) level of diabetic cardiomyocytes. Furthermore, Western blot data indicated that the diabetes-induced alterations in the cardiac ryanodine receptor Ca(2+) release channel's hyperphosphorylation decreased the FKBP12.6 protein level. Also, the high phosphorylated levels of PKA and CaMKII were prevented with propranolol treatment. Chronic treatment with propranolol seems to prevent diabetes-related changes in heart function by controlling intracellular Ca(2+) signaling and preventing the development of left ventricular remodeling in diabetic cardiomyopathy.

Diabetic individuals are at significantly greater risk of developing heart failure (HF) independent from other risk factors such as coronary artery disease (CAD) and hypertension. Diabetic cardiomyopathy (DCP) is defined as ventricular dysfunction in the absence of hypertension, coronary artery and valvular heart disease, which increases the risk of HF. Due to better understanding of its pathophysiology and clinical importance, DCP is more frequently recognized in daily practice. The most important mechanisms of DCP are hyperglycemia, insulin resistance/hyperinsulinemia, abnormal fatty acid metabolism, increased apoptosis, cardiac autonomic neuropathy and local renin-angiotensin-aldosterone system (RAAS) overactivation. Echocardiography is the most frequently used diagnostic method for the detection of this pathology. Currently, although there is no specific treatment for DCP, strict glycemic and concomitant risk factor controls seems to be the most important target strategy for prevention of the progression and treatment of DCP. In this article, we aim to provide an extensive review on the pathophysiology, diagnosis, management of DCP.

Purpose of Review: In patients with type 2 diabetes mellitus, treatment with metformin is associated with a lower cardiovascular morbidity and mortality, compared with alternative glucose-lowering drugs. It has been suggested that metformin might exert direct protective effects on the heart., Recent Findings: This review appraises recent experimental animal studies on the effect of metformin on myocardial ischaemia-reperfusion injury and remodeling. In murine models of myocardial infarction, the administration of metformin potently limits infarct size. Activation of adenosine monophosphate-activated protein kinase, increased formation of adenosine, and the prevention of opening of the mitochondrial permeability transition pore at reperfusion all contribute to this cardioprotective effect. In addition, metformin therapy attenuates postinfarction cardiac remodeling. There is evidence that activation of adenosine monophosphate-activated protein kinase and endothelial nitric oxide synthase, and a reduced collagen expression are crucial for this effect., Summary: The finding that metformin limits myocardial infarct size and remodeling in animal models of myocardial infarction suggests that patients suffering from myocardial ischaemia could benefit from treatment with metformin, even when these patients do not have diabetes. Currently, several clinical trials are being performed to test this hypothesis.

Objective: The pathogenesis of diabetic cardiomyopathy (DCM) is complex, and the therapeutic options available to treat DCM are limited. The present study was designed to investigate the effect of Aegle marmelos (L.) Correa (Rutaceae) leaf extract on early stage DCM in alloxan-induced diabetic rats., Methods: Diabetes was induced in Wistar rats (150-200 g) by injecting alloxan (150 mg kg(-1); i.p.). Ethanol extract of A. marmelos leaves was administered at varying doses (100, 200, and 400 mg kg(-1)) and tolbutamide (100 mg kg(-1)) as standard. Fasting blood glucose (FBG), total cholesterol, thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), lactate dehydrogenase (LDH) and creatine kinase (CK) were determined by standard methods., Results: A. marmelos extract (AME) was found to decrease the levels of FBG, total cholesterol, TBARS, LDH and CK, and increase the levels of GSH, CAT and SOD dose dependently as compared to diabetic control groups. The maximum dose-dependent decrease in TBARS (63.46%), LDH (34.04%), CK (53.14%), and increase in GSH (64.91%), CAT (59.34%), SOD (69.65%) was evident at an optimum dose of 200 mg kg(-1). Histopathological studies revealed salvage in the morphological derangements as indicated by absence of necrosis and marked decrease in inflammatory cells in AME-treated groups as compared to diabetic control., Conclusions: The present investigations conclude that treatment with AME attenuates the severity and improves the myocardium in the early stages of alloxan-induced DCM at a dose of 200 mg kg(-1).

There is little evidence from controlled prospective studies to support the low blood pressure goals stipulated for the treatment of hypertension by present guidelines, especially in high-risk patients with diabetes, renal insufficiency or coronary heart disease. Aim of this review is to scrutinize the potential benefit and risk of low blood pressure on the basis of recent studies and secondary analyses of older studies., Results: In patients with coronary heart disease or equivalent or with diabetes lowering systolic blood pressure to 130 to 135 mmHg reduced primary or secondary cardiovascular endpoints in the majority of studies. Between 120 and 129 mmHg some positive effects could be shown in patients with coronary heart disease but not in patients with diabetes or metabolic syndrome. In patients with diabetic or nondiabetic nephropathy including those with proteinurea no convincing data exist which show a better outcome with systolic blood pressure below 130 versus below 140 mmHg. However, several studies suggest that the risk of stroke may decrease by lowering systolic pressure to 120 mmHg or even lower. Below 120 mmHg an increased risk of cardiac and noncardiac events or death was shown in quite a number of studies. In patients between 70 and 80 years, current evidence suggests lowering systolic blood pressure to 135 to 145 mmHg and in those above 80 years to 145 to 155 mmHg. No evidence was found to justify different diastolic pressure goals for different groups of patients; optimal values fall between 70 and 85 mmHg. Limitations of recent studies are short follow-up, few event rates and small differences in achieved pressure between groups leaving uncertainty about long-term effects., Practical Consequences: Apart from prevention of stroke there is sparse evidence that lowering systolic blood pressure below 130 mmHg may be beneficial. Current evidence suggests that lowering systolic and diastolic pressure into a range of 130 to 140/70 to 85 may be adequate for all patients with the exception of children, adolescents and patients over 80 years. Further lowering of systolic pressure seems to offer little additional benefit and lowering diastolic pressure below 70 mmHg might increase risk.

Objective: This study was designed to investigate the effect of angiotensin (1-7), a Mas receptor agonist, and A-779, a Mas receptor antagonist, in rats with diabetic cardiomyopathy (DC)., Methods: Rats treated with a single injection of streptozotocin (50 mg/kg, intraperitoneal), developed DC after 8 weeks. The extent of DC was assessed by measuring the left ventricular weight/body weight (LVW/BW) ratio, absolute LVW, left ventricular developed pressure (LVDP), maximum change in left ventricular pressure over time (dp/dtmax), minimum change in left ventricular pressure over time (dp/dtmin), left ventricular (LV) protein content, LV collagen content, lipid profile, and serum nitrite/nitrate concentration. Test drug treatment was given from week 4 to week 8., Results: Angiotensin (1-7) treatment attenuated DC by significantly increasing LVDP, dp/dtmax, dp/dtmin, serum nitrite/nitrate concentration and significantly decreasing the LVW/BW ratio and LV collagen content. For the first time, this study has documented that endogenous angiotensin (1-7) regulates lipid profile in rats, and that treatment with angiotensin (1-7) significantly attenuates diabetes-induced changes in lipid profile. However, LV protein content and absolute LVW remain unaffected after treatment., Conclusion: Angiotensin (1-7) significantly attenuates DC in rats because of vasodilatory, antiproliferative and anifibrotic properties but also because of a significant decrease in dyslipidemia, the major culprit for cardiac dysfunctions in diabetes.

Objectives: This study has investigated the effect of atorvastatin on the progression of cardiac remodelling and ACE- 2 expression in diabetic myocardium in rats., Materials and Methods: Diabetes was induced in Holtzman rats with an intraperitoneal injection of streptozotocin. The animals were divided into 3 groups: (1) normal control rats, (2) diabetic rats and (3) diabetic rats treated orally with atorvastatin (50 mg/kg/day). After eight weeks of treatment, the hearts were removed for morphometric studies, collagen content assay and genetic expressions of ACE and ACE2 mRNA., Results: Myocardial hypertrophy index and collagen deposition were increased in diabetic rats, but not in the treated-diabetic rats, without producing changes in cholesterol levels. Myocardial ACE mRNA levels were increased while ACE2 mRNA levels were decreased in diabetic rats. Atorvastatin administration attenuated overexpression of ACE mRNA and overexpression of ACE-2 mRNA in diabetic rats., Conclusions: Our results indicate that atorvastatin, independently of its cholesterol-lowering capacity, lowers the ACE/ACE2 ratio to normal values and attenuates the development of adverse remodeling in the diabetic heart.

Rationale: Studies in transgenic mice showed the key role of (Pim-1) (proviral integration site for Moloney murine leukemia virus-1) in the control of cardiomyocyte function and viability., Objective: We investigated whether Pim-1 represents a novel mechanistic target for the cure of diabetic cardiomyopathy, a steadily increasing cause of nonischemic heart failure., Methods and Results: In streptozotocin-induced type 1 diabetic mice, Pim-1 protein levels declined during progression of cardiomyopathy, along with upregulation of Pim-1 inhibitors, protein phosphatase 2A, and microRNA-1. Moreover, diabetic hearts showed low levels of antiapoptotic B-cell lymphoma-2 (Bcl-2) protein and increased proapoptotic caspase-3 activity. Studies on adult rat cardiomyocytes and murine cardiac progenitor cells challenged with high glucose confirmed the in vivo expressional changes. In rescue studies, anti-microRNA-1 boosted Pim-1 and Bcl-2 expression and promoted cardiomyocyte and cardiac progenitor cell survival under high glucose conditions. Similarly, transfection with Pim-1 plasmid prevented high glucose-induced cardiomyocyte and cardiac progenitor cell apoptosis. Finally, a single intravenous injection of human PIM-1 via cardiotropic serotype-9 adeno-associated virus (1 × 10(10) or 5 × 10(10) plaque-forming units per animal) at 4 weeks after diabetes induction led to sustained cardiac overexpression of Pim-1 and improved diastolic function and prevented left ventricular dilation and failure. Histological examination showed reduced cardiomyocyte apoptosis and fibrosis in association with increased c-kit(+) cells and cardiomyocyte proliferation, whereas molecular analysis confirmed activation of the prosurvival pathway and conservation of sarcoendoplasmic reticulum Ca(2+)-ATPase and α-myosin heavy chain in Pim-1-treated hearts., Conclusions: Pim-1 downregulation contributes in the pathogenesis of diabetic cardiomyopathy. Systemic delivery of human PIM-1 via cardiotropic adeno-associated virus serotype-9 represents a novel and effective approach to treat diabetic cardiomyopathy.

Recently studies indicated that valsartan could prevent the progression of heart failure caused by diabetic cardiomyopathy (DCM), while the mechanisms were still poorly understood. The present study was designed to investigate whether valsartan could reduce the endoplasmic reticulum (ER) stress and DCM-induced cardiac remodeling. Our data has shown that valsartan can ameliorate ER stress-induced cardiac remodeling and myocardial apoptosis in DCM rats. By using of immunofluorescence and RT-PCR, valsartan has been found to play a protective role via down-regulating the expression of transcriptional induction of C/EBP homologous protein (CHOP) and p53 upregulated modulator of apoptosis (Puma), two crucial factors known to be implicated in the ER stress-induced myocardial apoptosis. And the expression level of Puma was closely related to CHOP. Thus, our experiment strongly suggests that the administration of valsartan can ameliorate the ER stress through blocking the activation of CHOP/Puma signaling pathway, which provides a new insight into the potential molecular mechanism of cardiomyocyte apoptosis., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Aim: To study whether calcium-modulating proteins CASQ2, FKBP12.6 and SERCA2a participate in diabetic cardiomyopathy, and whether the beneficial actions of testosterone, sildenafil or fructose diphosphate Sr (FDP-Sr) in the treatment of diabetic cardiomyopathy result from suppressing these molecules., Methods: Fifty male Sprague-Dawley (SD) rats were divided into five groups. Except for the normal group (non-diabetic), the other four groups were injected with streptozotocin (STZ, 60 mg/kg, ip) to induce diabetes. Four weeks after STZ injection, the four groups received sildenafil (12 mg·kg(-1)·d(-1), ig, for 4 week), FDP-Sr (200 mg/kg, ig, for 4 week), testosterone propionate (4 mg·kg(-1)·d(-1), sc, for 4 week), or no treatment, respectively., Results: In the diabetic rats, blood glucose, free fatty acids, triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C) were significantly increased, while high-density lipoprotein cholesterol (HDL-C) was significantly reduced, as compared to the non-diabetic rats. Cardiac dysfunction and myocardial hypertrophy of the diabetic rats were associated with increased mRNA and protein expression of iNOS, OBRb, and PKCɛ, while expression of CASQ2, SERCA2a, and FKBP12.6 was significantly down-regulated. Sildenafil and FDP-Sr, but not testosterone, significantly attenuated the biomarker abnormalities, without changing the metabolic abnormalities., Conclusion: CASQ2, FKBP12.6 and SERCA2a were down-regulated in diabetic cardiomyopathy. Sildenafil and FDP-Sr, but not testosterone, attenuated the cardiac dysfunction in diabetic cardiomyopathy, without changing the metabolic abnormalities, which may results from inhibiting oxidative and inflammatory cytokines and improving calcium homeostasis.

Objective: To study the protective effect of the Mixture of Shengmai Powder and Danshen Decoction (, abbreviated as the Mixture) in the rat model with type 2 diabetic cardiomyopathy in the rat model with type 2 diabetic cardiomyopathy, abbreviated as the Mixture) in the rat model with type 2 diabetic cardiomyopathy (DCM)., Methods: Forty-two SD rats with DCM model, established by the combination of insulin resistance by a high-fat diet with the damage of pancreatic islet β cells by intraperitoneal injection of high dose streptozotocin (50 mg/kg) once, were evaluated in the damage of the myocardium by electrocardiogram at the end of 12 weeks of grouping and intervention administration; the extent of damage in the myocardial subcellular structure was observed by electron microscopy; the content of myocardial collagen in the left cardiac ventricle was quantified by Masson staining test; the myocardial cell apoptosis was determined by TUNEL; the changes in the mRNA expression levels of thrombospodin-1 (TSP-1) and tribbles homolog 3 (TRB-3) by real-time quantitative PCR, the expression levels of myocardial TSP-1, tumor growth factorβ1 (TGF-β1), TRB-3, and chymase were detected by immunohistochemistry, and the changes in the expression levels of myocardial TSP-1, active-TGF-β1 (A-TGF-β1) and latent-TGF-β1 (L-TGF-β1) protein were tested by Western blotting., Results: Compared with the control group, the myocardial tissue was less damaged, and the extent of damage in the myocardial subcellular structure was less; the collagen fiber content and the cell apoptosis were reduced; the expression levels of TSP-1mRNA and TRB-3 mRNA, the expression levels of myocardial TSP-1, TGF-β1, TRB-3, and chymase, as well as the average expression levels of the myocardial TSP-1, A-TGFβ1, and L-TGF-β1 protein were decreased in the Mixture group., Conclusion: The Mixture of Shengmai Powder and Danshen Decoction could inhibit the process of myocardial fibrosis in the rat myocardium of DCM through multiple pathways and significantly delay the genesis and progress of DCM in hyperglycemic rats.

Type 2 diabetes is a disorder of glucose and lipid metabolism associated with increased risk of macrovascular and microvascular complications. The primary focus of treating type 2 diabetes is glycemic control; simultaneous management of cardiometabolic risk factors, including blood pressure, lipid profile and overweight/obesity, has been shown to improve outcomes. All patients with diabetes require individualized combination therapy including diet and exercise intervention to help prevent microvascular and macrovascular complications. Because primary care physicians in the United States provide the majority of care for patients with type 2 diabetes, this article discusses the management of cardiovascular risk with a specific focus on primary care. In addition, mechanisms by which existing and novel antidiabetes therapies may modulate the metabolic pathways and a review of the benefits of cardiovascular risk reduction using multifactorial, primary care-focused intervention strategies will be discussed. Finally, early- and late-stage disease management strategies are discussed.

This study examined the downstream signaling whereby hyperglycemia may lead to myocardial fibrosis and apoptosis in the left ventricle of diabetic rats. The effects of sulfurous mineral water or sodium hydrosulfide (NaHS) as possible modulators were also examined. Sulfurous mineral water (as drinking water) and NaHS (14μmol/kg/day, IP) were administered for 7 week to rats with streptozotocin (STZ)-induced diabetes. Hyperglycemia, overproduction of glycated hemoglobin (HbA1C) and serum decline in insulin, C-peptide and insulin like growth factor-I (IGF-I) were observed in diabetic rats. Up-regulation of gene expressions of nuclear factor (NF-κB), profibrogenic growth factor such as transforming growth factor-β1 (TGF-β1), matrix metalloproteniase-2 (MMP-2), procollagen-1 and Fas ligand (Fas-L) were observed in the left ventricle of diabetic rats. A linear positive correlation between TGF-β1 and MMP-2 was also detected in diabetic group. An increase in hydroxyproline level and a disturbance in oxidative balance were detected in heart of diabetic rats. Sulfurous mineral water and NaHS treatment possibly, by improving cardiac GSH level, counteracted the enhanced expression of NF-κB, the profibrogenic and apoptotic parameters. Histopathological examination was in accordance with the biochemical and molecular findings of this study. We suggest a novel therapeutic approach of sulfurous mineral water and exogenous supplementation of H(2)S in diabetic cardiomyopathy., (2010 Elsevier Inc. All rights reserved.)

Diabetic cardiomyopathy is a type of cardiac dysfunction resulting from diabetes, independent of vascular or valvular pathology. It clinically manifests initially as asymptomatic diastolic dysfunction and then progresses to symptomatic heart failure. Two major contributors to the development of diabetic cardiomyopathy, which are unique to diabetes, are hyperglycemia and diabetes-related alterations in myocardial metabolism. Diabetes mellitus is characterized by reduced glucose and lactate metabolism and enhanced fatty acid metabolism, which are the early consequences of the disease. Studies on the effect of intensive glucose control on heart failure events in patients with diabetes have been conducted with neutral results. However, no study on the effect of metabolic modulators on the prevention of heart failure has been reported. Trimetazidine, a 3-ketoacyl coenzyme A thiolase (3-KAT) inhibitor, shifts cardiac energy metabolism from free fatty acid oxidation to glucose oxidation by inhibiting mitochondrial long-chain 3-KAT, and is used clinically as an effective antianginal agent. Studies have shown that trimetazidine improves heart function in patients with idiopathic cardiomyopathy and in diabetic patients with cardiac ischemia or heart failure. In addition to being effective, trimetazidine has only mild side effects. Therefore, instead of routine administration of trimetazidine for the treatment of diabetic cardiomyopathy, we hypothesize that the early application of trimetazidine may prevent or ameliorate diabetic cardiomyopathy. In addition to life style modifications, ACEI, ARB, and beta-blockers, which have been recommended in the past, trimetazidine should be administered to those patients with impaired glucose tolerance or patients in the early course of diabetes. In this way, we may reduce the prevalence of heart failure and improve the long-term survival of patients with diabetes through early normalization of the myocardial substrate metabolism., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The scope of this review is to summarize the important roles of vitamin E family members as protective agents in cardiovascular pathologies of different types of disease states and particularly in diabetes, including some of our research results, to illustrate how this recent knowledge is helping to better understand the roles of the vitamin E family in biology, in animals and humans specifically. Cardiovascular disease, a general name for a wide variety of diseases, disorders and conditions, is caused by disorders of the heart and blood vessels. Cardiovascular disease is the world's largest killer, claiming 17.1 million lives a year. Cardiovascular complications result from multiple parameters including glucotoxicity, lipotoxicity, fibrosis. Obesity and diabetes mellitus are also often linked to cardiovascular disease. In fact, cardiovascular disease is the most life-threatening of the diabetic complications and diabetics are 2- to 4-fold more likely to die of cardiovascular-related causes than non-diabetics. In order to prevent the tendency of cardiovascular disease, primary prevention is needed by modifying risk factors. Several recent studies, besides earlier ones, have reported beneficial effects of therapy with antioxidant agents, including trace elements, vitamins (E and/or C), other antioxidants, against the cardiovascular dysfunction. Hence, the use of peroxisome proliferator activated receptor-α (PPARα) agonists to reduce fatty acid oxidation, of trace elements such as selenium as antioxidant and other antioxidants such as vitamins E and C, contributes to the prevention of these dysfunctions. Moreover, therapy with antioxidants and the above vitamins to prevent or delay the onset and development of cardiovascular complications in diabetic patients and animal models has been investigated although these studies showed inconsistent results.

Introduction: An increase in the oxidative stress and a decrease in the antioxidant levels have been described in diabetic patients, that have been related with the etiopathogenesis of diabetes and its chronic complications., Methods: We performed a non-systematic review to evaluate the relationship between oxidative stress and diabetes, and the possible effects of antioxidants in the prevention and treatment of diabetes and its complications., Results: The intervention studies including different antioxidants have not demonstrated any beneficial effect on cardiovascular and global morbimortality in different populations, including diabetic patients. Neither of these studies has demonstrated a beneficial effect of antioxidant supplementation on the prevention of diabetes. According to these studies, these substances can decrease lipid peroxidation, LDL-cholesterol particles oxidation and improve endothelial function and endothelial-dependent vasodilatation, without significant improvement in the metabolic control of these patients., Conclusions: The current evidence does not support the use of high doses of antioxidants on the prevention and treatment of diabetes and its complications.

Purpose: To examine the effect of a pharmaceutical care program on the coronary heart disease risk in elderly diabetic and hypertensive patients., Methods: A total of 200 elderly (> 60 years) diabetic and/or hypertensive patients were recruited into a randomized, controlled, prospective clinical trial with a 36-month follow-up, developed in a public primary health care unit in a municipality in the Brazilian State of Sao Paulo. A range of clinical measurements were evaluated at the baseline and up to 36 months afterwards. The intervention group patients received pharmaceutical care from a clinical pharmacist, whereas the control group patients received their usual care from the medical and nursing staff. The Framingham scoring method was used to estimate changes in the 10-year coronary heart disease risk scores of all the patients., Results: A total of 194 patients completed the study. Significant reductions (p < 0.05) in the mean values (baseline vs. 36 months) for the systolic blood pressure [156.7 mmHg vs 133.7 mmHg; P < 0.001), diastolic blood pressure (106.6 mmHg vs. 91.6 mmHg; P < 0.001),fasting glucose (135.1 mg/dL vs. 107.9 mg/dL; P < 0.001), hemoglobin A1C (7.7% vs. 7.0%; P <0.001), triglycerides (206.0 mg/dL vs. 152.5 mg/dL; P < 0.001), low-density lipoprotein (LDL)cholesterol (112.4 mg/dL vs. 102.0 mg/dL; P < 0.001), high-density lipoprotein cholesterol (55.5 mg/dL vs. 65.5 mg/dL; P < 0.001), total cholesterol (202.5 mg/dL vs. 185.9 mg/dL; P < 0.001), body mass index (26.2 kg/m2 vs. 26.1 kg/m2; P < 0.001), and abdominal circumference (103.2 cm vs. 102.5 cm; P= 0.001) were observed in the intervention group, whereas no significant changes were verified in the control group. The mean Framingham risk prediction score in the intervention group was 6.8% at baseline and decreased to 4.5%; P < 0.001) after 36 months, but remained unchanged in the control group., Conclusion: The pharmaceutical care program resulted in better clinical measurements and reduced the cardiovascular risk scores in elderly diabetic and hypertensive patients over a 36-month period.

Aims/hypothesis: The safety of metformin in heart failure has been questioned because of a perceived risk of life-threatening lactic acidosis, though recent studies have not supported this concern. We investigated the risk of all-cause mortality associated with individual glucose-lowering treatment regimens used in current clinical practice in Denmark., Methods: All patients aged ≥ 30 years hospitalised for the first time for heart failure in 1997-2006 were identified and followed until the end of 2006. Patients who received treatment with metformin, a sulfonylurea and/or insulin were included and assigned to mono-, bi- or triple therapy groups. Multivariable Cox proportional hazard regression models were used to assess the risk of all-cause mortality., Results: A total of 10,920 patients were included. The median observational time was 844 days (interquartile range 365-1,395 days). In total, 6,187 (57%) patients died. With sulfonylurea monotherapy used as the reference, adjusted hazard ratios for all-cause mortality associated with the different treatment groups were as follows: metformin 0.85 (95% CI 0.75-0.98, p = 0.02), metformin + sulfonylurea 0.89 (95% CI 0.82-0.96, p = 0.003), metformin + insulin 0.96 (95% CI 0.82-1.13, p = 0.6), metformin + insulin + sulfonylurea 0.94 (95% CI 0.77-1.15, p = 0.5), sulfonylurea + insulin 0.97 (95% CI 0.86-1.08, p = 0.5) and insulin 1.14 (95% CI 1.06-1.20, p = 0.0001)., Conclusions/interpretation: Treatment with metformin is associated with a low risk of mortality in diabetic patients with heart failure compared with treatment with a sulfonylurea or insulin.

In addition to progressive pancreatic β-cell failure resulting in impaired insulin secretion, and increased insulin resistance in muscle and liver, incretin hormone-related abnormalities have been identified as key underlying defects in patients with type 2 diabetes mellitus. Treatment goals for patients with type 2 diabetes should be aligned with the basic defects of the disease. Many of the available antidiabetes agents correct hyperglycemia but do not impact other cardiovascular risk factors, and may actually aggravate some. This paper reviews the role of defects in the incretin system in the pathophysiology of type 2 diabetes, and discusses recent advances in the use of incretinbased agents that target the fundamental disease mechanisms of type 2 diabetes. The incretinbased agents reduce hyperglycemia and provide beneficial effects on surrogate markers of cardiovascular risk, including weight gain, elevated blood pressure, and dyslipidemia.

Background: The development of diabetic cardiomyopathy is multifactorial. Insulin resistance (IR) and excessive activity of the renin-angiotensin system are confirmed reasons for diabetic cardiomyopathy. Renin-angiotensin system (RAS) inhibitors can reduce tissue Ang II levels, with beneficial effects on cardiovascular function. Therefore, in type-2 diabetes mellitus (T2DM), blockade of the RAS may have the function of protecting against diabetic cardiomyopathy through increasing insulin sensitivity and inhibiting excessive activity of RAS. However, this has not been confirmed., Methods: The effect of valsartan, an angiotensin receptor blocker (ARB), on diabetic cardiomyopathy in the presence of T2DM was studied. Wistar rats with T2DM and T2DM treated with valsartan were studied. Glucose infusion rates (GIR), index of IR, heart weight, the heart weight-to-body weight ratio (HW/BW), myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were measured., Results: GIR in T2DM rats and T2DM rats treated with valsartan decreased (P < 0.01). In T2DM rats treated with valsartan, heart weight, myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were higher than in control rats, but lower than in T2DM rats. In rats with T2DM, GIR was negatively and significantly correlated with all the variables. However, in T2DM rats treated with valsartan or normal control rats, none of the correlations was significant., Conclusions: In the presence of T2DM, diabetic cardiomyopathy is related with IR. Valsartan can not alleviate IR, but can protect against diabetic cardiomyopathy and remove the correlation between IR and diabetic cardiomyopathy.

Resveratrol (RSV), a natural phenolic compound, has been found to display cardiovascular protective and insulin-sensitizing properties. In this study, the effects of RSV and its combination with insulin on mortality, hemodynamics, insulin signaling, and nitrosative stress were compared in streptozotocin (STZ)-induced diabetic rats with or without acute myocardial ischemia/reperfusion (I/R) injury. Under normoxic conditions, cardiac systolic and diastolic functions and insulin-mediated Akt/GLUT4 (glucose transporter 4) activation were impaired in STZ-diabetic rats. The combination of RSV and insulin significantly prevented the above diabetes-associated abnormalities. Notwithstanding that, the diabetic state rendered the animals more susceptible to myocardial I/R injury, and the mortality rate and inducible nitric oxide synthase (iNOS)/nitrotyrosine protein expression and superoxide anion production were also further increased in I/R-injured diabetic hearts. In contrast, RSV treatment alone resulted in a lower mortality rate (from 62.5 to 18%) and better cardiac systolic function than its combination with insulin. RSV also inhibited iNOS/nitrotyrosine protein overexpression and superoxide anion overproduction in I/R-injured diabetic myocardium. Hyperglycemia, impairment of insulin signaling, overexpression of iNOS/nitrotyrosine, and superoxide anion overproduction were markedly rescued by the combination treatment, which did not show an improvement in mortality rate (30%) or cardiac performance over RSV treatment alone. These results indicate that insulin and RSV synergistically prevented cardiac dysfunction in diabetes and this may be in parallel with activation of the insulin-mediated Akt/GLUT4 signaling pathway. Although activation of the protective signal (Akt/GLUT4) and suppression of the adverse markers (iNOS, nitrotyrosine, and superoxide anion) were simultaneously observed in insulin and RSV combination treatment, insulin counteracted the advantage of RSV in diabetics with acute heart attack., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Zinc is a vital element in maintaining the normal structure and physiology of cells. The fact that it has an important role in states of cardiovascular diseases has been studied and described by several research groups. It appears to have protective effects in coronary artery disease and cardiomyopathy. Intracellular zinc plays a critical role in the redox signaling pathway, whereby certain triggers such as ischemia and infarction lead to release of zinc from proteins and cause myocardial damage. In such states, replenishing with zinc has been shown to improve cardiac function and prevent further damage. Thus, the area of zinc homeostasis is emerging in cardiovascular disease research. The goal of this report is to review the current knowledge and suggest further avenues of research., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Objective: Effects of diabetes mellitus on myocardium were investigated, by assessing levels of heat shock protein (HSP) 70, and efficacy of glutamine was tested., Materials and Methods: Thirty male rats were divided into three groups: control group (Group 1), diabetic group (Group 2) and glutamine-induced diabetic group (Group 3). Diabetes was created by intravenous streptozocin injection. Rats were examined one month later for cardiac complications of diabetes. Serum and tissue samples were obtained to measure HSP 70 levels., Results: Following streptozocin administration, glucose levels increased markedly. This resulted in a significant increase in HSP 70 in serum and tissues. When Group 3 was compared with other groups, HSP 70 was more increased in serum and tissues. When Groups 2 and 3 were compared, more increased HSP 70 values were observed in Group 3, statistical significance was obtained for left atrial and left ventricular HSP 70 levels. Elevated blood glucose was correlated with elevated HSP 70 levels. Increased serum HSP 70 levels were correlated with tissue HSP 70 values., Conclusions: HSP 70 levels increase in the myocardium of rats in diabetes mellitus as a protective mechanism. Levels of HSP 70 may further be increased with parenteral administration of glutamine. Efficacy of glutamine is more pronounced in left heart structures.

Background: Patients' awareness of the increased cardiovascular risk associated with their diabetes is poorly documented., Aim: The aim of this study was to assess the awareness of diabetes complications among patients with diabetes in Ireland., Methods: Patients attending diabetes outpatient clinics in two teaching hospitals in different regions of the country were invited to complete a questionnaire., Results: A total of 258 (59.3% male) patients completed the questionnaire; mean age 57.8 years. On questioning, 53.5% reported cardiovascular disease as a potential complication of diabetes, with awareness rates of 61.2, 17.1, 16.3 and 12% for retinopathy, stroke, peripheral vascular disease and amputation, respectively. Disappointingly, less than half of respondents felt that improvements in diet and exercise could potentially reduce their cardiovascular risk., Conclusions: Awareness of cardiovascular risk and knowledge of effective measures to reduce this were low in our study and an alternative means of education may need to be considered.