Overexpression of glutathione peroxidase attenuates myocardial remodeling and preserves diastolic function in diabetic heart

2006 ◽  
Vol 291 (5) ◽  
pp. H2237-H2245 ◽  
Author(s):  
Shouji Matsushima ◽  
Shintaro Kinugawa ◽  
Tomomi Ide ◽  
Hidenori Matsusaka ◽  
Naoki Inoue ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Glutathione Peroxidase ◽  
Diastolic Function ◽  
Interstitial Fibrosis ◽  
Systolic Function ◽  
Thiobarbituric Acid ◽  
Left Ventricular ◽  
Diabetic Heart ◽  
Lv Remodeling ◽  
Aortic Blood Pressure

Oxidative stress plays an important role in the structural and functional abnormalities of diabetic heart. Glutathione peroxidase (GSHPx) is a critical antioxidant enzyme that removes H2O2 in both the cytosol and mitochondia. We hypothesized that the overexpression of GSHPx gene could attenuate left ventricular (LV) remodeling in diabetes mellitus (DM). We induced DM by injection of streptozotocin (160 mg/kg ip) in male GSHPx transgenic mice (TG+DM) and nontransgenic wildtype littermates (WT+DM). GSHPx activity was higher in the hearts of TG mice compared with WT mice, with no significant changes in other antioxidant enzymes. LV thiobarbituric acid-reactive substances measured in TG+DM at 8 wk were significantly lower than those in WT+DM (58 ± 3 vs. 71 ± 5 nmol/g, P < 0.05). Heart rate and aortic blood pressure were comparable between groups. Systolic function was preserved normal in WT+DM and TG+DM mice. In contrast, diastolic function was impaired in WT+DM and was improved in TG+DM as assessed by the deceleration time of peak velocity of transmitral diastolic flow and the time needed for relaxation of 50% maximal LV pressure to baseline value (tau; 13.5 ± 1.2 vs. 8.9 ± 0.7 ms, P < 0.01). The TG+DM values were comparable with those of WT+Control (tau; 7.8 ± 0.2 ms). Improvement of LV diastolic function was accompanied by the attenuation of myocyte hypertrophy, interstitial fibrosis, and apoptosis. Overexpression of GSHPx gene ameliorated LV remodeling and diastolic dysfunction in DM. Therapies designed to interfere with oxidative stress might be beneficial to prevent cardiac abnormalities in DM.

scholarly journals Nebivolol improves diastolic dysfunction and myocardial remodeling through reductions in oxidative stress in the transgenic (mRen2) rat

2012 ◽  
Vol 302 (11) ◽  
pp. H2341-H2351 ◽  
Author(s):  
Lixin Ma ◽  
Rukhsana Gul ◽  
Javad Habibi ◽  
Ming Yang ◽  
Lakshmi Pulakat ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Protein Kinase ◽  
Nadph Oxidase ◽  
Diastolic Dysfunction ◽  
Diastolic Function ◽  
Interstitial Fibrosis ◽  
Left Ventricular ◽  
No Synthase ◽  
Sprague Dawley ◽  
Amp Activated Protein Kinase

Angiotensin II contributes to myocardial tissue remodeling and interstitial fibrosis through NADPH oxidase-mediated generation of oxidative stress in the progression of heart failure. Recent data have suggested that nebivolol, a third-generation β-blocker, improves diastolic dysfunction by targeting nitric oxide (NO) and metabolic pathways that decrease interstitial fibrosis. We sought to determine if targeting NO would improve diastolic function in a model of tissue renin-angiotensin system overactivation. We used the transgenic (TG) (mRen2)27 rat, which overexpresses the murine renin transgene and manifests insulin resistance and left ventricular dysfunction. We treated 6- to 7-wk-old TG (mRen2)27 rats and age-matched Sprague-Dawley control rats with nebivolol (10 mg·kg−1·day−1) or placebo via osmotic minipumps for a period of 21 days. Compared with Sprague-Dawley control rats, TG (mRen2)27 rats displayed a prolonged diastolic relaxation time and reduced initial filling rate associated with increased interstitial fibrosis and left ventricular hypertrophy. These findings were temporally related to increased NADPH oxidase activity and subunits p47 phox and Rac1 and increased total ROS and peroxynitrite formation in parallel with reductions in the antioxidant heme oxygenase as well as the phosphorylation/activation of endothelial NO synthase and PKB/Akt. Treatment with nebivolol restored diastolic function and interstitial fibrosis through increases in the phosphorylation of 5′-AMP-activated protein kinase, Akt, and endothelial NO synthase and reductions in oxidant stress. These results support that targeting NO with nebivolol treatment improves diastolic dysfunction through reducing myocardial oxidative stress by enhancing 5′-AMP-activated protein kinase and Akt activation of NO biosynthesis.

Effect of overweight and obesity on the left ventricular systolic and diastolic functions in patients with acute myocardial infarction

2012 ◽  
Vol 35 (4) ◽  
pp. 229 ◽  
Author(s):  
Fatih Poyraz ◽  
Murat Turfan ◽  
Sinan A. Kocaman ◽  
Huseyin U. Yazici ◽  
Nihat Sen ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Diastolic Function ◽  
Systolic Function ◽  
Study Groups ◽  
Left Ventricular ◽  
Normal Weight ◽  
Overweight And Obesity ◽  
Weight Group ◽  
Normal Weight Group ◽  
Diastolic Functions

Purpose: The purpose of this study was to evaluate whether a association exits among overweight and obesity and left ventricular systolic and diastolic functions in patients admitted with first ST-elevation myocardial infarction (STEMI). Methods: The present study was performed on 451 consecutive patients diagnosed with first STEMI (376 men, 75 women; mean age 56.1±10.8 years). The patients were classified into three groups based on their body mass index (BMI) as normal weight (BMI < 25 kg/m2), overweight (BMI: 25-29.9 kg/m2) and obese (BMI > 30 kg/m2). Echocardiographic features were evaluated and compared among the three groups. Results: Mitral annulus E velocities were higher in obese individuals than normal weight group (p < 0.01). In contrast, mitral A velocities were lower (p =0.03); consequently, E\A and E'\A' ratios were lower (both p =0.01) in the obese group with respect to normal weight group. When the correction of entire variations existing among the groups were performed using multivariate linear regressions analyses, it turned out that BMI was independently associated with E/A (β= -0.19, p =0.044) and with E'/A' (β= -0.016, p=0.021). Ejection fraction, wall motion score index and myocardial S velocities were comparable among the study groups (p > 0.05). Conclusion: These results suggest that while obesity has no adverse effect on the left ventricular systolic function, it has unfavorable consequences on the left ventricular diastolic function in the patients with first STEMI. In contrast, no unfavorable effects of overweight on the left ventricular systolic and diastolic function were detected.

scholarly journals Antioxidant Activity of the Isoflavonoids from the Roots of Maackia amurensis

2013 ◽  
Vol 8 (5) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Nadezda I. Kulesh ◽  
Sergey A. Fedoreyev ◽  
Marina V. Veselova ◽  
Natalia P. Mischenko ◽  
Vladimir A. Denisenko ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Activity ◽  
Glutathione Peroxidase ◽  
Column Chromatography ◽  
Thiobarbituric Acid ◽  
Formalin Injection ◽  
Thiobarbituric Acid Reactive Substances ◽  
H Nmr ◽  
Maackia Amurensis

Seven isoflavonoids, including a new glycoside, (6a R,11a R)-medicarpin-3- O-gentiobioside (6), were isolated from the roots of Maackia amurensis using repeated column chromatography on a Toyopearl HW-50F sorbent and identified by HPLC–PDA–MS, 1H NMR, 13C, 1H–1H COSY, HSQC NMR and HMBC NMR analyses as daidzin (1), genistein-7- O-gentiobioside (2), pseudobaptigenin-7- O-gentiobioside (3), formononetin-7- O-gentiobioside (4), (6a R,11a R)-maackiain-3- O-gentiobioside (5), and 5- O-methylgenistein-7- O-gentiobioside (7). In the model of oxidative stress induced by formalin injection, the isolated isoflavone and pterocarpan glucosides 1-7 were shown to reduce the formation of malondialdehyde (MDA) and other thiobarbituric acid reactive substances (TBARS), as well as glutathione peroxidase (GPO) activity in rats.

scholarly journals Arrest of atherosclerosis progression after interruption of GH replacement in adults with congenital isolated GH deficiency

2012 ◽  
Vol 166 (6) ◽  
pp. 977-982 ◽  
Author(s):  
Vanessa P Araujo ◽  
Manuel H Aguiar-Oliveira ◽  
Joselina L M Oliveira ◽  
Hertaline M N Rocha ◽  
Carla R P Oliveira ◽  
...  
Keyword(s):  
Ejection Fraction ◽  
Diastolic Function ◽  
Gh Deficiency ◽  
Systolic Function ◽  
Receptor Gene ◽  
Intima Media Thickness ◽  
Posterior Wall ◽  
Left Ventricular ◽  
Carotid Imt ◽  
Gh Replacement

ObjectiveGH replacement therapy (GHRT) in adult-onset GH deficiency (AOGHD) reduces carotid intima-media thickness (IMT) and increases myocardial mass, with improvement of systolic and diastolic function. These observations have reinforced the use of GHRT on AOGHD. Conversely, we have previously reported that in adults with lifetime congenital and severe isolated GH deficiency (IGHD) due to a mutation in GHRH receptor gene (GHRHR), a 6-month treatment with depot GH increased carotid IMT, caused the development of atherosclerotic plaques, and an increase in left ventricular mass index (LVMI), posterior wall, and septal thickness and ejection fraction. Such effects persisted 12 months after treatment (12-month washout – 12mo).MethodsWe have studied the cardiovascular status (by echocardiography and carotid ultrasonography) of these subjects 60 months after completion of therapy (60-month washout – 60mo).ResultsCarotid IMT reduced significantly from 12 to 60mo, returning to baseline (pre-therapy) value. The number of individuals with plaques was similar at 12 and 60mo, remaining higher than pre-therapy. LVMI, relative posterior wall thickness, and septum thickness did not change between 12 and 60mo, but absolute posterior wall increased from 12 to 60mo. Systolic function, evaluated by ejection fraction and shortening fraction, was reduced at 60mo in comparison with 12mo returning to baseline levels. The E/A wave ratio (expression of diastolic function) decreased at 60mo compared with both 12mo and baseline.ConclusionsIn adults with lifetime congenital IGHD, the increase in carotid IMT elicited by GHRT was transitory and returned to baseline 5 years after therapy discontinuation. Despite this, the number of subjects with plaques remained stable at 60mo and higher than at baseline.

Antioxidant defenses and metabolic depression in a pulmonate land snail

1995 ◽  
Vol 268 (6) ◽  
pp. R1386-R1393 ◽  
Author(s):  
M. Hermes-Lima ◽  
K. B. Storey
Keyword(s):  
Oxidative Stress ◽  
Glutathione Peroxidase ◽  
Defense Mechanisms ◽  
Antioxidant Defense ◽  
Thiobarbituric Acid ◽  
Land Snail ◽  
Land Snails ◽  
Antioxidant Defenses ◽  
Glutathione S Transferase ◽  
Hypometabolic State

During arousal from estivation oxygen consumption by land snails (Otala lactea) increases severalfold. To determine whether snails prepared for an accompanying rise in the rates of oxyradical generation by altering their antioxidant defense mechanisms, changes in the activities of antioxidant enzymes and lipid peroxidation products were quantified in foot and hepatopancreas of control, 30-day estivating, and aroused snails. Compared with controls, estivating O. lactea showed significant increases in the activities of foot muscle superoxide dismutase (SOD) (increasing by 56-67%), catalase (51-72%), and glutathione S-transferase (79-108%), whereas, in hepatopancreas, SOD (57-78%) and glutathione peroxidase (93-144%) increased. Within 40 min after arousal began, hepatopancreas glutathione peroxidase activity had returned to control values, but SOD showed a further 70% increase in activity but then returned to control levels by 80 min. Estivation had no effect on total glutathione (GSH + 2 GSSG) concentrations in tissues, but GSSG content had increased about twofold in both organs of 30-day dormant snails. Lipid peoxidation (quantified as thiobarbituric acid reactive substances) was significantly enhanced at the onset of arousal from dormancy, indicating that oxidative stress and tissue damage occurred at this time. The data suggest that antioxidant defenses in snail organs are increased while snails are in the hypometabolic state as a preparation for oxidative stress during arousal.

Abstract 370: Type 2 Diabetes Is Associated with the Exacerbation of Heart Failure via Increasing Myocardial NAD(P)H Oxidase-Derived Superoxide Production

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Shintaro Kinugawa ◽  
Shouji Matsushima ◽  
Takashi Yokota ◽  
Yukihiro Ohta ◽  
Naoki Inoue ◽  
...  
Keyword(s):  
Heart Failure ◽  
Type 2 Diabetes ◽  
Diastolic Pressure ◽  
Interstitial Fibrosis ◽  
Left Ventricular ◽  
Lung Weight ◽  
Tissue Mass ◽  
Tibial Length ◽  
Lv Remodeling

Type 2 diabetes mellitus (DM) adversely affects the outcomes in patients with myocardial infarction (MI), which is associated with the development of left ventricular (LV) remodeling and failure. NAD(P)H oxidase-derived superoxide (O 2 − ) production is increased in DM. However, its pathophysiological significance in advanced post-MI LV failure associated with DM remains unestablished. We thus determined whether an inhibitor of NAD(P)H oxidase activation, apocynin, could attenuate the exacerbated LV remodeling and heart failure after MI in high-fat diet (HFD)-induced obese mice with DM. Male C57BL/6J mice were fed on either HFD or normal diet (ND) for 8 weeks. At 4 weeks of feeding, MI was created in all mice by ligating left coronary artery. MI mice were treated with either apocynin (10 mmol/l in drinking water; n = 10 for ND and n = 11 for HFD) or vehicle (n = 15 for ND and n = 13 for HFD). HFD significantly increased body weight (BW), adipose tissue mass, fasting plasma glucose and insulin levels compared to ND after 4 and 8 weeks. HFD + MI had significantly greater LV end-diastolic diameter (LVEDD; 5.7 ± 0.1 vs. 5.3 ± 0.2 mm) by echocardiography, end-diastolic pressure (EDP; 12 ± 2 vs. 8 ± 1 mmHg) and lung weight/tibial length (10.1 ± 0.3 vs. 8.7 ± 0.7 mg/mm) than ND + MI, which was accompanied by an increased interstitial fibrosis of non-infarcted LV. Treatment of HFD + MI with apocynin significantly decreased LVEDD (5.4 ± 0.1 mm), LVEDP (9.7 ± 0.8 mmHg), lung weight/tibial length (9.0 ± 0.3 mg/mm), and concomitantly interstitial fibrosis of non-infarcted LV to ND + MI level without affecting BW, glucose metabolism, infarct size and aortic pressure. On the other hand, treatment of ND + MI with apocynin did not affect LV remodeling and failure. NAD(P)H oxidase activity, O 2 − production measured by lucigenin chemiluminescence, and thiobarbituric acid-reactive substances were increased in non-infarcted LV tissues from HFD + MI, all of which were also attenuated by apocynin to ND + MI level. Type 2 DM was associated with the exacerbation of LV remodeling and failure after MI via increasing NAD(P)H oxidase derived O 2 − production, which may be a novel important therapeutic target in advanced heart failure with DM.

Abstract 14952: Hemodynamic Comparison of Left Ventricular Function in Pressure Overload- versus Volume Overload-Induced Heart Failure Models by Invasive Pressure-Volume Analysis

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Mihály Ruppert ◽  
Christian Karime ◽  
Alex A Sayour ◽  
Attila Oláh ◽  
Dávid Nagy ◽  
...  
Keyword(s):  
Heart Failure ◽  
Systolic Function ◽  
Pressure Overload ◽  
Volume Overload ◽  
Detailed Comparison ◽  
Left Ventricular ◽  
Lv Function ◽  
Arterial Elastance ◽  
Lv Remodeling ◽  
Av Shunt

Introduction: Both sustained left ventricular (LV) pressure overload (PO) and volume overload (VO) induces LV remodeling and eventually development of heart failure (HF). Using rat models, the present study aimed to provide a detailed comparison of distinct aspects of LV function in PO- and VO-induced HF. Methods: PO and VO was induced by transverse aortic constriction (TAC, n=12) and aortocaval shunt (AV-shunt, n=12) creation respectively. Controls underwent corresponding sham operations (n=11). LV remodeling was characterized by echocardiography, histology, qRT PCR, and western blot. LV function was assessed by invasive pressure-volume (P-V) analysis. Results: Both sustained PO and VO resulted in the development of HF, as evidenced by increased LV BNP mRNA expression, pulmonary edema, and characteristic symptoms. While the extent of LV hypertrophy was comparable between the HF models, PO induced concentric while VO evoked eccentric LV remodeling. P-V analysis revealed impaired systolic function in both HF models. Accordingly, decreased ejection fraction and impaired ventriculo-arterial coupling (calculated as the ratio of arterial elastance/LV contractility [VAC]: 0.38±0.05 vs. 1.30±0.13, ShamTAC vs. TAC and 0.52±0.08 vs. 1.17±0.13, ShamAV-Shunt vs. AV-shunt; p<0.05) was detected in both HF models. However, in case of VO the severely reduced LV contractility (slope of end-systolic P-V relationship: 1.79±0.19 vs. 0.52±0.06, ShamAV-Shunt vs. AV-shunt, p<0.05 and 2.14±0.28 vs. 2.03±0.21, ShamTAC vs. TAC p>0.05) underpinned the contractility-afterload mismatch, while in case of PO the increased afterload (arterial elastance: 0.77±0.07 vs. 2.64±0.28, ShamTAC vs. TAC and 0.80±0.07 vs. 0.54±0.05, ShamAV-Shunt vs. AV-shunt; p<0.05) was the main determinant. Furthermore, prolongation of active relaxation occurred to a greater extent in case of PO. In addition, increased myocardial stiffness was only observed in PO-induced HF. Conclusion: Systolic function was reduced in both HF models. However, different factors underpinned the impaired VAC in case of VO (reduced LV contractility) and PO (increased arterial elastance). Furthermore, although diastolic function deteriorated in both models, it occurred to a greater extent in case of PO.

P901 Left ventricular diastolic and systolic functions are compromised in patients with hypothyroidism

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
R Tafarshiku ◽  
M Y Henein ◽  
V Berisha-Muharremi ◽  
I Bytyci ◽  
P Ibrahimi ◽  
...  
Keyword(s):  
Diastolic Function ◽  
Systolic Function ◽  
White Blood Cells ◽  
Left Ventricular ◽  
Blood Analysis ◽  
Lv Function ◽  
Anthropometric Parameters ◽  
Age And Gender ◽  
And Gender ◽  
Lv Diastolic Function

Abstract Background and Aim Long standing hypothyroidism may impair myocardial relaxation, but its effect on systolic myocardial function is still controversial. The aim of this study was to investigate left ventricular (LV) systolic and diastolic function in patients with hypothyroidism. Methods This study included 81 (age 42 ± 13 years, 92% female) patients with hypothyroidism, and 22 age and gender matched controls. All subjects underwent a detailed clinical examination followed by a complete biochemical blood analysis including thyroid function assessment and anthropometric parameters measurements. LV function was assessed by 2 dimensional, M-mode and Tissue-Doppler Doppler echocardiographic examination performed in the same day. Results Patients had lower waist/hip ratio (p &lt; 0.001), higher urea level (p = 0.002) and lower white blood cells (p = 0.011), compared to controls. All other clinical, biochemical and anthropometric data did not differ between the two groups. Patients had impaired LV diastolic function (lower E wave [p &lt; 0.001], higher A wave [p = 0.028], lower E/A ratio [p &lt; 0.001], longer E wave deceleration time [p = 0.01], and higher E/e’ ratio [p &lt; 0.001]), compared with controls. Although LV global systolic function did not differ between groups, LV longitudinal systolic function was compromised in patients (lateral mitral annular plane systolic excursion - MAPSE [p = 0.005], as were lateral and septal TDI s’ [p &lt; 0.001 for both]). Conclusion In patients with hypothyroidism, in addition to compromised LV diastolic function, LV longitudinal systolic function is also impaired compared to healthy subjects of the same age and gender. These findings suggest significant subendocardial function impairment, reflecting potentially micro-circulation disease, that requires optimum management.

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