scholarly journals Exercise Training Attenuates Upregulation of p47phoxand p67phoxin Hearts of Diabetic Rats

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Neeru M. Sharma ◽  
Brandon Rabeler ◽  
Hong Zheng ◽  
Eugenia Raichlin ◽  
Kaushik P. Patel
Keyword(s):  
Exercise Training ◽  
Nadph Oxidase ◽  
Cardiac Function ◽  
Diabetic Cardiomyopathy ◽  
Underlying Mechanism ◽  
Diabetic Rats ◽  
Diabetic Patients ◽  
Cardiac Tissues ◽  
Beneficial Effects ◽  
Collagen Iii

Exercise training (ExT) is currently being used as a nonpharmacological strategy to improve cardiac function in diabetic patients. However, the molecular mechanism(s) underlying its beneficial effects remains poorly understood. Oxidative stress is known to play a key role in the pathogenesis of diabetic cardiomyopathy and one of the enzyme systems that produce reactive oxygen species is NADH/NADPH oxidase. The goal of this study was to investigate the effect of streptozotocin- (STZ-) induced diabetes on expression ofp47phoxandp67phox, key regulatory subunits of NADPH oxidase, in cardiac tissues and determine whether ExT can attenuate these changes. Four weeks after STZ treatment, expression ofp47phoxandp67phoxincreased 2.3-fold and 1.6-fold, respectively, in left ventricles of diabetic rats and these increases were attenuated with three weeks of ExT, initiated 1 week after onset of diabetes. In atrial tissues, there was increased expression ofp47phox(74%), which was decreased by ExT in diabetic rats. Furthermore, increased collagen III levels in diabetic hearts (52%) were significantly reduced by ExT. Taken together, ExT attenuates the increased expression ofp47phoxandp67phoxin the hearts of diabetic rats which could be an underlying mechanism for improving intracardiac matrix and thus cardiac function and prevent cardiac remodeling in diabetic cardiomyopathy.

Beneficial effects of exercise training in heart failure are lost in male diabetic rats

2017 ◽  
Vol 123 (6) ◽  
pp. 1579-1591
Author(s):  
Dalila Boudia ◽  
Valérie Domergue ◽  
Philippe Mateo ◽  
Loubina Fazal ◽  
Mathilde Prud’homme ◽  
...  
Keyword(s):  
Heart Failure ◽  
Exercise Training ◽  
Ejection Fraction ◽  
Cardiac Function ◽  
Diabetic Rats ◽  
Diabetic Patients ◽  
Coronary Artery Ligation ◽  
Standard Diet ◽  
Beneficial Effects ◽  
Patients With Heart Failure

Exercise training has been demonstrated to have beneficial effects in patients with heart failure (HF) or diabetes. However, it is unknown whether diabetic patients with HF will benefit from exercise training. Male Wistar rats were fed either a standard (Sham, n = 53) or high-fat, high-sucrose diet ( n = 66) for 6 mo. After 2 mo of diet, the rats were already diabetic. Rats were then randomly subjected to either myocardial infarction by coronary artery ligation (MI) or sham operation. Two months later, heart failure was documented by echocardiography and animals were randomly subjected to exercise training with treadmill for an additional 8 wk or remained sedentary. At the end, rats were euthanized and tissues were assayed by RT-PCR, immunoblotting, spectrophotometry, and immunohistology. MI induced a similar decrease in ejection fraction in diabetic and lean animals but a higher premature mortality in the diabetic group. Exercise for 8 wk resulted in a higher working power developed by MI animals with diabetes and improved glycaemia but not ejection fraction or pathological phenotype. In contrast, exercise improved the ejection fraction and increased adaptive hypertrophy after MI in the lean group. Trained diabetic rats with MI were nevertheless able to develop cardiomyocyte hypertrophy but without angiogenic responses. Exercise improved stress markers and cardiac energy metabolism in lean but not diabetic-MI rats. Hence, following HF, the benefits of exercise training on cardiac function are blunted in diabetic animals. In conclusion, exercise training only improved the myocardial profile of infarcted lean rats fed the standard diet. NEW & NOTEWORTHY Exercise training is beneficial in patients with heart failure (HF) or diabetes. However, less is known of the possible benefit of exercise training for HF patients with diabetes. Using a rat model where both diabetes and MI had been induced, we showed that 2 mo after MI, 8 wk of exercise training failed to improve cardiac function and metabolism in diabetic animals in contrast to lean animals.

scholarly journals Cardioprotective effects of polydatin against myocardial injury in diabetic rats via inhibition of NADPH oxidase and NF-κB activities

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ying-Ying Tan ◽  
Lei-Xin Chen ◽  
Ling Fang ◽  
Qi Zhang
Keyword(s):  
Nadph Oxidase ◽  
Diabetic Cardiomyopathy ◽  
High Glucose ◽  
Myocardial Injury ◽  
Diabetic Rats ◽  
Left Ventricular ◽  
Diabetic Patients ◽  
Therapeutic Effects ◽  
H9c2 Cells ◽  
Cardioprotective Effects

Abstract Background Diabetic cardiomyopathy is a main cause of the increased morbidity in diabetic patients, no effective treatment is available so far. Polydatin, a resveratrol glucoside isolated from the Polygonum cuspidatum, was found by our and others have antioxidant and cardioprotective activities. Therapeutic effects of polydatin on diabetic cardiomyopathy and the possible mechanisms remains unclear. This study aimed to investigate the cardioprotective effects and underlying mechanisms of polydatin on myocardial injury induced by hyperglycemia. Methods Diabetes in rats was made by high-fat diet combined with multiple low doses of streptozotocin, and then treated with polydatin (100 mg·kg-1·day-1, by gavage) for 8 weeks. Cardiac function was examined by echocardiography. Myocardial tissue and blood samples were collected for histology, protein and metabolic characteristics analysis. In cultured H9c2 cells with 30 mM of glucose, the direct effects of polydatin on myocyte injury were also observed. Results In diabetic rats, polydatin administration significantly improved myocardial dysfunction and attenuated histological abnormalities, as evidenced by elevating left ventricular shortening fraction and ejection fraction, as well as reducing cardiac hypertrophy and interstitial fibrosis. In cultured H9c2 cells, pretreatment of polydatin dose-dependently inhibited high glucose-induced cardiomyocyte injury. Further observation evidenced that polydatin suppressed the increase in the reactive oxygen species levels, NADPH oxidase activity and inflammatory cytokines production induced by hyperglycemia in vivo and in vitro. Polydatin also prevented the increase expression of NOX4, NOX2 and NF-κB in the high glucose -stimulated H9c2 cells and diabetic hearts. Conclusions Our results demonstrate that the cardioprotective effect of polydatin against hyperglycemia-induced myocardial injury is mediated by inhibition of NADPH oxidase and NF-κB activity. The findings may provide a novel understanding the mechanisms of the polydatin to be a potential treatment of diabetic cardiomyopathy.

scholarly journals SGLT1 Inhibition Attenuates Apoptosis in Diabetic Cardiomyopathy via the JNK and p38 Pathway

2021 ◽  
Vol 11 ◽  
Author(s):  
Na Lin ◽  
Hui Lin ◽  
Qi Yang ◽  
Wenqiang Lu ◽  
Zhenzhu Sun ◽  
...  
Keyword(s):  
Diabetic Cardiomyopathy ◽  
Area Under The Curve ◽  
Underlying Mechanism ◽  
Male Rats ◽  
Diabetic Patients ◽  
Roc Curve Analysis ◽  
Beneficial Effects ◽  
Sodium Glucose Cotransporter ◽  
H9c2 Cardiomyocytes ◽  
P38 Pathway

Background: Recent studies have revealed that a novel selective sodium-glucose cotransporter 1 (SGLT1) inhibiton has shown beneficial effects in cardiovascular diseases. However, the question of whether SGLT1 inhibition influences diabetic cardiomyopathy (DCM) remains unanswered. In this study, we investigated the influence and underlying mechanism of SGLTI inhibition on DCM.Methods: SGLT1 levels were measured in diabetic patients with similar conditions who visited our hospital from January to December 2019. Wistar male rats (n = 50) were divided into five groups: control, diabetes induced by streptozotocin infusion, and diabetes treated with 0.5, 1.0, or 1.5 mg/kg mizagliflozin via stomach gavage for 12 weeks. H9C2 cardiomyocytes were treated with mizagliflozin and then exposed to a high glucose concentration (30 mmol/L). TUNEL assays were performed, and bcl2, bax, p-p38, p-Erk, p-JNK and caspase-3 levels were measured. We used siRNA and an SGLT1 overexpression plasmid to detect the effects of SGLT1.Results: SGLT1 levels were significantly elevated in DCM patients, and receiver operating characteristic (ROC) curve analysis identified SGLT1 as influencing DCM. The area under the curve (AUC) was 0.705 (p < 0.05), with 65.8% sensitivity, and 62.2% specificity. SGLT1 inhibition appeared to attenuate apoptosis in DCM via the JNK and p38 pathway.Conclusion: SGLT1 can be used as a marker for the diagnosis of DCM, and SGLT1 inhibition can attenuate apoptosis, thereby suppressing DCM development via the JNK and p38 pathway.

Hypertriglyceridemia in experimental diabetes: relationship to cardiac dysfunction

1994 ◽  
Vol 72 (5) ◽  
pp. 447-455 ◽  
Author(s):  
Brian Rodrigues ◽  
Paul F. Grassby ◽  
Mary L. Battell ◽  
Stephanie Y. N. Lee ◽  
John H. McNeill
Keyword(s):  
Cardiac Function ◽  
Cardiac Dysfunction ◽  
Heart Function ◽  
Diabetic Rats ◽  
Left Ventricular ◽  
Plasma Triglyceride ◽  
Diabetic Rat ◽  
Diabetic Patients ◽  
Beneficial Effects ◽  
Rate Of Increase

The incidence of mortality from cardiovascular disease is higher in diabetic patients. The objective of the present investigation was to test die hypothesis that the diabetes-induced depression in cardiac function may be due to hypertriglyceridemia. Hyperlipidemia and a depressed left ventricular developed pressure and rate of increase and decrease of ventricular pressure (±dP/dt) were produced in isolated hearts from rats made diabetic with streptozotocin compared with hearts from control animals. This depressed cardiac performance was successfully prevented by hydralazine treatment (for 3 weeks), which also lowered plasma triglyceride levels and suggested that hyperlipidemia may be important in altering cardiac function in experimental diabetic rats. The beneficial effects of clofibrate, verapamil, prazosin, enalapril, and benazepril administration were then studied in diabetic rats. The treatments (with die exception of enalapril) significantly reduced plasma triglyceride levels but did not prevent die onset of heart dysfunction in chronically diabetic rats. These studies suggest that in the chronically diabetic rat, hypertriglyceridemia may not be as important as previously suggested, in the development of cardiac dysfunction. Since acute dichloroacetate perfusion improves cardiac function in 6 week (but not 24 week) diabetic rats, it appears more likely that improving myocardial glycose utilization is more critical than triglyceride lowering, in preventing cardiac dysfunction in die diabetic rat at this time point.Key words: diabetes, triglycerides, heart function, glucose oxidation.

Comparative evaluation of atenolol and metoprolol on cardiovascular complications associated with streptozotocin-induced diabetic rats

2007 ◽  
Vol 85 (8) ◽  
pp. 831-836 ◽  
Author(s):  
Shraddha V. Bhadada ◽  
Ramesh K. Goyal
Keyword(s):  
Heart Rate ◽  
Serum Insulin ◽  
Cardiovascular Complications ◽  
Serum Glucose ◽  
Diabetic Rats ◽  
Diabetic Patients ◽  
Cardiac Tissues ◽  
Insulin Levels ◽  
Beneficial Effects ◽  
Glucose Levels

Recently, various clinical studies have indicated that lipophilic β-blockers reduce the coronary mortality in diabetic patients; however, systematic studies have not been reported. The objective of the present investigation was to compare the effects of chronic treatment with metoprolol and atenolol on cardiovascular complications in streptozotocin (STZ)-induced diabetic rats. Injection of STZ produced hyperglycemia, hypoinsulinemia, hyperlipidemia, increased blood pressure, cardiac hypertrophy, reduction in heart rate, and structural alterations in cardiac tissues. Metoprolol and atenolol effectively prevented the development of hypertension in diabetic rats. Metoprolol treatment produced a slight but significant reduction in serum glucose levels with elevation in serum insulin levels, while atenolol produced a slight increase in glucose levels but no effect on insulin levels. Moreover, neither metoprolol nor atenolol treatment reduced the elevated cholesterol levels in diabetic rats. Metoprolol treatment significantly prevented STZ-induced increase in triglyceride levels, but atenolol failed to produce this effect. Metoprolol exhibited a minimal improvement in STZ-induced bradycardia, whereas atenolol produced a further reduction in heart rate. Histological examination showed metoprolol treatment also prevented STZ-induced hypertrophy and some of the alterations in cardiomyocytes. In conclusion, our data suggest that metoprolol has some beneficial effects over atenolol with respect to cardiovascular complications associated with diabetes mellitus.

scholarly journals FGF1ΔHBS prevents diabetic cardiomyopathy by maintaining mitochondrial homeostasis and reducing oxidative stress via AMPK/Nur77 suppression

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Dezhong Wang ◽  
Yuan Yin ◽  
Shuyi Wang ◽  
Tianyang Zhao ◽  
Fanghua Gong ◽  
...  
Keyword(s):  
Diabetic Cardiomyopathy ◽  
Metabolic Regulation ◽  
Cardiac Injury ◽  
Serum Levels ◽  
Ros Generation ◽  
Dependent Manner ◽  
Cardiac Tissues ◽  
Beneficial Effects

AbstractAs a classically known mitogen, fibroblast growth factor 1 (FGF1) has been found to exert other pleiotropic functions such as metabolic regulation and myocardial protection. Here, we show that serum levels of FGF1 were decreased and positively correlated with fraction shortening in diabetic cardiomyopathy (DCM) patients, indicating that FGF1 is a potential therapeutic target for DCM. We found that treatment with a FGF1 variant (FGF1∆HBS) with reduced proliferative potency prevented diabetes-induced cardiac injury and remodeling and restored cardiac function. RNA-Seq results obtained from the cardiac tissues of db/db mice showed significant increase in the expression levels of anti-oxidative genes and decrease of Nur77 by FGF1∆HBS treatment. Both in vivo and in vitro studies indicate that FGF1∆HBS exerted these beneficial effects by markedly reducing mitochondrial fragmentation, reactive oxygen species (ROS) generation and cytochrome c leakage and enhancing mitochondrial respiration rate and β-oxidation in a 5’ AMP-activated protein kinase (AMPK)/Nur77-dependent manner, all of which were not observed in the AMPK null mice. The favorable metabolic activity and reduced proliferative properties of FGF1∆HBS testify to its promising potential for use in the treatment of DCM and other metabolic disorders.

Kir6.1 improves cardiac dysfunction in diabetic cardiomyopathy via the AKT-Foxo1 signaling pathway

2020 ◽  
Author(s):  
Jinxin Wang ◽  
Jing Bai ◽  
Peng Duan ◽  
Hao Wang ◽  
Yang Li ◽  
...  
Keyword(s):  
Cardiac Function ◽  
Signaling Pathway ◽  
Diabetic Cardiomyopathy ◽  
Cardiac Dysfunction ◽  
Diabetic Patients ◽  
Protein Levels ◽  
Inwardly Rectifying Potassium Channel ◽  
Transmission Electron ◽  
Hematoxylin And Eosin ◽  
And Function

Abstract Background: Diabetic cardiomyopathy (DCM) severely impairs the health of diabetic patients. Previous studies have shown that the expression of inwardly rectifying potassium channel 6.1 (Kir6.1) in heart mitochondria is significantly reduced in type 1 diabetes. However, whether its expression and function are changed and what role it plays in type 2 DCM have not been reported. This study investigated the role and mechanism of Kir6.1 in DCM.Methods: The cardiac function in mice was analyzed by echocardiography, ELISA, hematoxylin and eosin staining, TUNEL and transmission electron microscopy. The mitochondrial function in cardiomyocytes was measured by the oxygen consumption rate and the mitochondrial membrane potential (ΔΨm). Kir6.1 expression at the mRNA and protein levels was analyzed by quantitative real-time PCR and western blotting (WB), respectively. The protein expression of t-AKT, p-AKT, t-Foxo1, and p-Foxo1 was analyzed by WB.Results: We found that the cardiac function and the Kir6.1 expression in DCM mice were decreased. Kir6.1 overexpression improved cardiac dysfunction and upregulated the phosphorylation of AKT and Foxo1 in the DCM mouse model. Furthermore, Kir6.1 overexpression also improved cardiomyocyte dysfunction and upregulated the phosphorylation of AKT and Foxo1 in cardiomyocytes with insulin resistance. In contrast, cardiac-specific Kir6.1 knockout aggravated the cardiac dysfunction and downregulated the phosphorylation of AKT and Foxo1 in DCM mice. Furthermore, Foxo1 activation downregulated the expression of Kir6.1 and decreased the ΔΨm in cardiomyocytes. In contrast, Foxo1 inactivation upregulated the expression of Kir6.1 and increased the ΔΨm in cardiomyocytes. Chromatin immunoprecipitation assay demonstrated that the Kir6.1 promoter region contains a functional Foxo1-binding site .Conclusions: Kir6.1 improves cardiac dysfunction in DCM, probably through the AKT-Foxo1 signaling pathway. Moreover, the crosstalk between Kir6.1 and the AKT-Foxo1 signaling pathway may provide new strategies for reversing the defective signaling in DCM.

scholarly journals Isosteviol ameliorates diabetic cardiomyopathy in rats by inhibiting ERK and NF-κB signaling pathways

2018 ◽  
Vol 238 (1) ◽  
pp. 47-60 ◽  
Author(s):  
Sheng-Gao Tang ◽  
Xiao-Yu Liu ◽  
Ji-Ming Ye ◽  
Ting-Ting Hu ◽  
Ying-Ying Yang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Blood Glucose ◽  
Diabetic Cardiomyopathy ◽  
Nuclear Factor Κb ◽  
Diabetic Rats ◽  
Signal Pathways ◽  
Mortality And Morbidity ◽  
Beneficial Effects ◽  
Male Wistar Rats ◽  
Glucose Plasma

Diabetes-induced injury of myocardium, defined as diabetic cardiomyopathy (DCM), accounts for significant mortality and morbidity in diabetic population. Alleviation of DCM by a potent drug remains considerable interests in experimental and clinical researches because hypoglycemic drugs cannot effectively control this condition. Here, we explored the beneficial effects of isosteviol sodium (STVNa) on type 1 diabetes-induced DCM and the potential mechanisms involved. Male Wistar rats were induced to diabetes by injection of streptozotocin (STZ). One week later, diabetic rats were randomly grouped to receive STVNa (STZ/STVNa) or its vehicle (STZ). After 11 weeks of treatment or 11 weeks treatment following 4 weeks of removal of the treatment, the cardiac function and structure were evaluated and related mechanisms were investigated. In diabetic rats, oxidative stress, inflammation, blood glucose and plasma advanced glycation end products (AGEs) were significantly increased, whereas superoxide dismutase 2 (SOD-2) expression and activity were decreased. STVNa treatment inhibited cardiac hypertrophy, fibrosis and inflammation, showed similar ratio of heart to body weight and antioxidant capacities almost similar to the normal controls, which can be sustained at least 4 weeks. Moreover, STVNa inhibited diabetes-inducted stimulation of both extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB) signal pathways. However, blood glucose, plasma AGE and insulin levels were not altered by STVNa treatment. These results indicate that STVNa may be developed into a potent therapy for DCM. The mechanism underlying this therapeutic effect involves the suppression of oxidative stress and inflammation by inhibiting ERK and NF-κB without changing blood glucose or AGEs.

scholarly journals Quetiapine Attenuates the Neuroinflammation and Executive Function Deficit in Streptozotocin-Induced Diabetic Mice

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Kexin Wang ◽  
Feng Song ◽  
Hongxing Wang ◽  
Jun-hui Wang ◽  
Yu Sun
Keyword(s):  
Cognitive Deficit ◽  
Neuroprotective Effect ◽  
Underlying Mechanism ◽  
Diabetic Mouse ◽  
Diabetic Patients ◽  
Diabetic Mice ◽  
Protein Loss ◽  
Monocyte Chemoattractant Protein 1 ◽  
Beneficial Effects ◽  
Increased Risk

Diabetic patients are at increased risk for developing memory and cognitive deficit. Prior studies indicate that neuroinflammation might be one important underlying mechanism responsible for this deficit. Quetiapine (QTP) reportedly exerts a significant neuroprotective effect in animal and human studies. Here, we investigated whether QTP could prevent memory deterioration and cognitive impairment in a streptozotocin- (STZ-) induced diabetic mouse model. In this study, we found that STZ significantly compromised the behavioral performance of mice in a puzzle box test, but administering QTP effectively attenuated this behavioral deficit. Moreover, our results showed that QTP could significantly inhibit the activation of astrocytes and microglia in these diabetic mice and reduce the generation and release of two cytokines, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1). Meanwhile, QTP also prevented the protein loss of the synaptic protein synaptophysin (SYP) and myelin basic protein (MBP). Here, our results indicate that QTP could inhibit neuroinflammatory response from glial cells and block the injury of released cytokines to neurons and oligodendrocytes in diabetic mice (DM). These beneficial effects could protect diabetic mice from the memory and cognitive deficit. QTP may be a potential treatment compound to handle the memory and cognitive dysfunction in diabetic patients.

Sign in / Sign up

Export Citation Format

Share Document