Chronic intermittent hypobaric hypoxia prevents cardiac dysfunction through enhancing antioxidation in fructose-fed rats

2013 ◽  
Vol 91 (5) ◽  
pp. 332-337 ◽  
Author(s):  
Jing-Jing Zhou ◽  
Yan Wei ◽  
Li Zhang ◽  
Jiao Zhang ◽  
Lan-Ying Guo ◽  
...  

High-fructose intake induces metabolic syndrome and cardiac dysfunction. Chronic intermittent hypobaric hypoxia (CIHH) preserves cardiac function during ischemia. We hypothesized that CIHH restores the impaired cardiac function in fructose-fed rats. Sprague–Dawley rats were randomly subject to treatment with fructose (10% fructose in drinking water for 6 weeks), CIHH (simulated 5000 m altitude, 6 h/day for 6 weeks in a hypobaric chamber), and CIHH plus fructose groups. In addition to an increase in blood pressure, fructose feeding caused elevated serum levels of glucose, fasting insulin and insulin C peptide, triglyceride, cholesterol, and mass ratio of heart to body. CIHH treatment decreased the arterial blood pressure, serum levels of biochemical markers, and cardiac hypertrophy in fructose-fed rats. Furthermore, CIHH treatment improved the recovery of left ventricular function after ischemia–reperfusion procedure (30 min global no-flow ischemia followed by 60 min of reperfusion) in rats with or without fructose feeding. In addition, CIHH treatment caused a significant increase in superoxide dismutase (SOD) activity and decrease in malondialdehyde level in cardiac myocardium experiencing ischemia–reperfusion in control and fructose-fed rats. Collectively, these data suggest that CIHH improve impaired cardiac function in fructose-fed rats through enhancing antioxidation in the myocardium.

2019 ◽  
Vol 133 (3) ◽  
pp. 497-513 ◽  
Author(s):  
Chayodom Maneechote ◽  
Siripong Palee ◽  
Sasiwan Kerdphoo ◽  
Thidarat Jaiwongkam ◽  
Siriporn C. Chattipakorn ◽  
...  

Abstract An uncontrolled balance of mitochondrial dynamics has been shown to contribute to cardiac dysfunction during ischemia/reperfusion (I/R) injury. Although inhibition of mitochondrial fission could ameliorate cardiac dysfunction, modulation of mitochondrial fusion by giving a fusion promoter at different time-points during cardiac I/R injury has never been investigated. We hypothesized that giving of a mitochondrial fusion promoter at different time-points exerts cardioprotection with different levels of efficacy in rats with cardiac I/R injury. Forty male Wistar rats were subjected to a 30-min ischemia by coronary occlusion, followed by a 120-min reperfusion. The rats were then randomly divided into control and three treated groups: pre-ischemia, during-ischemia, and onset of reperfusion. A pharmacological mitochondrial fusion promoter-M1 (2 mg/kg) was used for intervention. Reduced mitochondrial fusion protein was observed after cardiac I/R injury. M1 administered prior to ischemia exerted the highest level of cardioprotection by improving both cardiac mitochondrial function and dynamics regulation, attenuating incidence of arrhythmia, reducing infarct size and cardiac apoptosis, which led to the preservation of cardiac function and decreased mortality. M1 given during ischemia and on the onset of reperfusion also exerted cardioprotection, but with a lower efficacy than when given at the pre-ischemia time-point. Attenuating a reduction in mitochondrial fusion proteins during myocardial ischemia and at the onset of reperfusion exerted cardioprotection by attenuating mitochondrial dysfunction and dynamic imbalance, thus reducing infarct size and improving cardiac function. These findings indicate that it could be a promising intervention with the potential to afford cardioprotection in the clinical setting of acute myocardial infarction.


2021 ◽  
Author(s):  
Nattayaporn Apaijai ◽  
Kewarin Jinawong ◽  
Kodchanan Singhanat ◽  
Thidarat Jaiwongkam ◽  
Sasiwan Kerdphoo ◽  
...  

High fat diet (HFD) consumption induces prediabetes and left ventricular dysfunction through many pathways including the cell death pathway, necroptosis. Although benefits of necroptosis inhibitor (necrostatin-1 or Nec-1) in the brain of prediabetic rats have been shown, the effects of Nec-1 on cardiac autonomic function, blood pressure, and cardiac function, and the mechanisms involved have not been investigated. Male Wistar rats were fed with either a normal diet (n=8) or HFD (n=24) for 12 weeks to induce prediabetes. Prediabetic rats were randomly assigned into 3 interventional groups (n=8/group): 1) vehicle, 2) Nec-1 (1.65 mg/kg, sc injection), and 3) metformin (300 mg/kg, oral gavage feeding). Treatments lasted for 8 weeks. Normal saline was given to the vehicle group and a non-interventional group. Metabolic parameters, cardiac function and biochemical parameters were assessed. Prediabetic rats exhibited peripheral metabolic impairment as indicated by increased body weight, hyperinsulinemia with euglycemia, and dyslipidemia. Prediabetic rats also exhibited cardiac autonomic imbalance, high blood pressure, cardiac dysfunction, cardiac mitochondrial dysfunction, mitochondrial dynamic imbalance, and increased necroptosis and apoptosis. Treatment with Nec-1 did not affect peripheral metabolic parameters, however it effectively reduced cardiac autonomic imbalance, blood pressure, and cardiac dysfunction via reduced cardiac inflammation, necroptosis, mitochondrial dysfunction, and increased mitochondrial fusion. Treatment with metformin reduced peripheral metabolic impairment and cardiac dysfunction via decreased cardiac mitochondrial dysfunction, mitochondrial dynamic imbalance, and apoptosis. In summary, Nec-1 directly suppressed necroptosis, cardiac mitochondrial dysfunction, and increased mitochondrial fusion independent to peripheral metabolic function, leading to an improvement in cardiac function in prediabetic rats.


2012 ◽  
Vol 90 (7) ◽  
pp. 851-862 ◽  
Author(s):  
Ting-Ting Li ◽  
Yi-Shuai Zhang ◽  
Lan He ◽  
Bin Liu ◽  
Rui-Zheng Shi ◽  
...  

Myeloperoxidase (MPO) is involved in myocardial ischemia–reperfusion (IR) injury and vascular peroxidase (VPO) is a newly identified isoform of MPO. This study was conducted to explore whether VPO is involved in IR-induced cardiac dysfunction and apoptosis. In a rat Langendorff model of myocardial IR, the cardiac function parameters (left ventricular pressure and the maximum derivatives of left ventricular pressure and coronary flow), creatine kinase (CK) activity, apoptosis, VPO1 activity were measured. In a cell (rat-heart-derived H9c2 cells) model of hypoxia–reoxygenation (HR), apoptosis, VPO activity, and VPO1 mRNA expression were examined. In isolated heart, IR caused a marked decrease in cardiac function and a significant increase in apoptosis, CK, and VPO activity. These effects were attenuated by pharmacologic inhibition of VPO. In vitro, pharmacologic inhibition of VPO activity or silencing of VPO1 expression significantly suppressed HR-induced cellular apoptosis. Our results suggest that increased VPO activity contributes to IR-induced cardiac dysfunction and inhibition of VPO activity may have the potential clinical value in protecting the myocardium against IR injury.


Author(s):  
В.В. Шерстнев ◽  
М.А. Грудень ◽  
В.П. Карлина ◽  
В.М. Рыжов ◽  
А.В. Кузнецова ◽  
...  

Цель - исследование взаимосвязи факторов риска сердечно-сосудистых заболеваний и развития предгипертонии. Методика. Проведен сравнительный и корреляционный анализы показателей модифицируемых и немодифицируемых факторов риска сердечно-сосудистых заболеваний у обследованных лиц в возрасте 30-60 лет с «оптимальным» артериальным давлением, (n = 63, АД <120/80 мм рт.ст.) и лиц с предгипертонией (n = 52, АД = 120-139/80-89 мм рт.ст.). Результаты. Показано, что лица с предгипертонией по сравнению с группой лиц, имеющих «оптимальное» артериальное давление характеризуются статистически значимо повышенным содержанием холестерина и холестерина липопротеидов низкой плотности, интеллектуальным характером трудовой деятельности, а также значимыми сочетаниями факторов риска: повышенный уровень холестерина липопротеидов низкой плотности с интеллектуальным характером трудовой деятельности; повышенное содержание креатинина с уровнем триглициридов; наследственная отягощенность по заболеваниям почек и интеллектуальным характером трудовой деятельности; наследственная отягощенность по сахарному диабету и гипертрофия левого желудочка сердца. У лиц с предгипертонией документированы перестройки структуры взаимосвязи (количество, направленность и сила корреляций) между показателями факторов риска в сравнении с лицами, имеющими «оптимальное» артериальное давление. Заключение. Выявленные особенности взаимосвязей факторов риска сердечно-сосудистых заболеваний при предгипертонии рассматриваются как проявление начальной стадии дизрегуляционной патологии и нарушения регуляции физиологических систем поддержания оптимального уровня артериального давления. The aim of the study was to investigate the relationship between risk factors for cardiovascular disease and development of prehypertension. Methods. Comparative and correlation analyses of modifiable and non-modifiable risk factors for cardiovascular disease were performed in subjects aged 30-60 with «optimal» blood pressure (n = 63, BP <120/80 mm Hg) and prehypertension (n = 52, BP = 120-139 / 80-89 mm Hg). Results. The group with prehypertension compared with the «optimal» blood pressure group had significantly increased serum levels of low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol, sedentary/intellectual type of occupation, and significant combinations of risk factors. The risk factor combinations included an increased level of LDL cholesterol and a sedentary/intellectual occupation; increased serum levels of creatinine and triglycerides; hereditary burden of kidney disease and a sedentary/intellectual occupation; hereditary burden of diabetes mellitus and cardiac left ventricular hypotrophy. In subjects with prehypertension compared to subjects with «optimal» blood pressure, changes in correlations (correlation number, direction, and strength) between parameters of risk factors were documented. Conclusion. The features of interrelationships between risk factors for cardiovascular disease observed in prehypertension are considered a manifestation of early dysregulation pathology and disordered regulation of physiological systems, which maintain optimal blood pressure.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
N Landler ◽  
S Bro ◽  
B Feldt-Rasmussen ◽  
D Hansen ◽  
A.L Kamper ◽  
...  

Abstract Background The cardiovascular mortality of patients with chronic kidney disease (CKD) is 2–10 times higher than in the average population. Purpose To estimate the prevalence of abnormal cardiac function or structure across the stages CKD 1 to 5nonD. Method Prospective cohort study. Patients with CKD stage 1 to 5 not on dialysis, aged 30 to 75 (n=875) and age-/sex-matched controls (n=173) were enrolled consecutively. All participants underwent a health questionnaire, ECG, morphometric and blood pressure measurements. Blood and urine were analyzed. Echocardiography was performed. Left ventricle (LV) hypertrophy, dilatation, diastolic and systolic dysfunction were defined according to current ESC guidelines. Results 63% of participants were men. Mean age was 58 years (SD 12.6 years). Mean eGFR was 46.7 mL/min/1,73 m (SD 25.8) for patients and 82.3 mL/min/1,73 m (SD 13.4) for controls. The prevalence of elevated blood pressure at physical exam was 89% in patients vs. 53% in controls. Patients were more often smokers and obese. Left ventricular mass index (LVMI) was slightly, albeit insignificantly elevated at CKD stages 1 & 2 vs. in kontrols: 3.1 g/m2, CI: −0.4 to 6.75, p-value 0.08. There was no significant difference in LV-dilatation between patients and controls. Decreasing diastolic and systolic function was observed at CKD stage 3a and later: LVEF decreased 0.95% (CI: −1.5 to −0.2), GLS increased 0.5 (CI: 0.3 to 0.8), and OR for diastolic dysfunction increased 3.2 (CI 1.4 to 7.3) pr. increment CKD stage group. Conclusion In accordance to previous studies, we observe in the CPHCKD cohort study signs of early increase of LVMI in patients with CKD stage 1 & 2. Significant decline in systolic and diastolic cardiac function is apparent already at stage 3 CKD. Figure 1. Estimated GFR vs. GLS & histogram of GLS Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): The Capital Region of Denmark


Author(s):  
Kendrick Lee ◽  
Steven R. Laviolette ◽  
Daniel B. Hardy

Abstract Background Cannabis use in pregnancy leads to fetal growth restriction (FGR), but the long-term effects on cardiac function in the offspring are unknown, despite the fact that fetal growth deficits are associated with an increased risk of developing postnatal cardiovascular disease. We hypothesize that maternal exposure to Δ9-tetrahydrocannabinol (Δ9-THC) during pregnancy will impair fetal development, leading to cardiac dysfunction in the offspring. Methods Pregnant Wistar rats were randomly selected and administered 3 mg/kg of Δ9-THC or saline as a vehicle daily via intraperitoneal injection from gestational days 6 to 22, followed by echocardiogram analysis of cardiac function on offspring at postnatal days 1 and 21. Heart tissue was harvested from the offspring at 3 weeks for molecular analysis of cardiac remodelling. Results Exposure to Δ9-THC during pregnancy led to FGR with a significant decrease in heart-to-body weight ratios at birth. By 3 weeks, pups exhibited catch-up growth associated with significantly greater left ventricle anterior wall thickness with a decrease in cardiac output. Moreover, these Δ9-THC-exposed offsprings exhibited increased expression of collagen I and III, decreased matrix metallopeptidase-2 expression, and increased inactivation of glycogen synthase kinase-3β, all associated with cardiac remodelling. Conclusions Collectively, these data suggest that Δ9-THC-exposed FGR offspring undergo postnatal catch-up growth concomitant with cardiac remodelling and impaired cardiac function early in life. Impact To date, the long-term effects of perinatal Δ9-THC (the main psychoactive component) exposure on the cardiac function in the offspring remain unknown. We demonstrated, for the first time, that exposure to Δ9-THC alone during rat pregnancy results in significantly smaller hearts relative to body weight. These Δ9-THC-exposed offsprings exhibited postnatal catch-up growth concomitant with cardiac remodelling and impaired cardiac function. Given the increased popularity of cannabis use in pregnancy along with rising Δ9-THC concentrations, this study, for the first time, identifies the risk of perinatal Δ9-THC exposure on early postnatal cardiovascular health.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S Tzortzis ◽  
I Ikonomidis ◽  
H Triantafyllidi ◽  
J Thymis ◽  
A Frogoudaki ◽  
...  

Abstract Background We investigated the effects of antihypertensive treatment on vascular function, longitudinal and torsional deformation in hypertensives. Methods In 200 untreated patients with arterial hypertension (age 52.5±11.6 years, 56% females), we measured at baseline and after a 3-year of antihypertensive treatment (160 received ACEi± diuretics and 40 CCBs± diuretics): a) 24h ambulatory blood pressure b) Carotid-femoral pulse wave velocity (PWV) b) Coronary flow reserve (CFR), LV mass index (LVMI), the global longitudinal strain (GLS) and diastolic (LongSRSE) strain rate, peak twisting (Tw-deg) and untwisting at mitral valve opening (UtwMVO), at peak E (UtwE) and at the end of the E wave (UtwendE) of the mitral inflow as well as twisting (TwVel-deg/sec) velocity using speckle tracking imaging. We calculated the % change of LV untwisting as difference between peakTw and UtwMVO, UtwpeakE and UtwendE. Results Compared to baseline, there was an improvement of GLS (−19.9±3.4 vs. −18.7±3.1%), LongSRS (−1.08±0.22 vs. −0.98±0.26 1/s), LongSRE (1.09±0.36 vs. 0.99±0.31 1/s), peak Tw (16.2±5.1 vs. 18.7±5.9 deg), Tw velocity, and the %LV untwisting (31.04±19.28 vs 26.02±15.69% at MVO, 60.04±19.78 vs 53.96±19.76% at peakE and 79.98±14.24 vs 75.90±17.01% at endE) post-treatment. In parallel, CFR (2.72±0.61 vs. 2.55±0.64), PWV (10.34±1.93 vs. 11.2±2.08 m/s) and LVMI were improved (p&lt;0.01 for all comparisons). By ANOVA, the interaction term between changes of all the above parameters and antihypertensive treatment (ACE inhibitors vs calcium channel blockers) was not significant (p&gt;0.05). By multivariate analysis, the reduction of 24h meanBP and PWV independently determined the respective improvement of GLS (b=0.478 and b=0.248 respectively), LongS (b=0.428 and b=0.201 respectively) as well as Twisting (b=0.449 and b=0.294 respectively) after adjusting for changes in LV mass, CFR and atherosclerotic risk factors (p&lt;0.05). Conclusions Long-term optimal blood pressure control with ACE inhibitors and CCBs improves LV longitudinal and torsional mechanics in hypertensives in parallel with arterial stiffness and blood pressure. This improvement in LV deformation and twisting was independently related to changes in arterial blood pressure and arterial stiffness. Funding Acknowledgement Type of funding source: None


1992 ◽  
Vol 73 (6) ◽  
pp. 2675-2680 ◽  
Author(s):  
E. Mellow ◽  
E. Redei ◽  
K. Marzo ◽  
J. R. Wilson

Stimulation of endogenous opiate secretion worsens circulatory dysfunction in several forms of shock, in part by inhibiting sympathetic activity. To investigate whether endogenous opiates have a similar effect in chronic heart failure (HF), we measured beta-endorphin concentrations and hemodynamic responses to naloxone infusion (2 mg/kg bolus + 2 mg.kg-1 x h-1) in six control (C) dogs and eight dogs with low-output HF produced by 3 wk of rapid ventricular pacing. The dogs with HF exhibited reduced arterial blood pressure (C, 123 +/- 4 vs. HF, 85 +/- 7 mmHg; P < 0.01) and cardiac outputs (C, 179 +/- 14 vs. HF, 76 +/- 2 ml.min-1 x kg-1; P < 0.01) and elevated plasma norepinephrine concentrations (C, 99 +/- 12 vs. HF, 996 +/- 178 pg/ml; P < 0.01) but normal beta-endorphin concentrations (C, 30 +/- 11 vs. HF, 34 +/- 12 pg/ml; P = NS). Naloxone produced similar transitory increases in blood pressure (C, 14 +/- 5 vs. HF, 26 +/- 25%) and cardiac output (C, 37 +/- 13 vs. HF, 22 +/- 15%) in both groups (both P = NS). No significant changes in norepinephrine concentration or systemic vascular resistance were observed in either group. These findings suggest that beta-endorphin secretion does not exacerbate circulatory dysfunction in chronic heart failure.


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