Working heart function in diabetes is not improved by spironolactone treatment

2003 ◽  
Vol 81 (5) ◽  
pp. 493-496 ◽  
Author(s):  
Subodh Verma ◽  
Violet G Yuen ◽  
Mitesh Badiwala ◽  
Todd J Anderson ◽  
John H McNeill

Aldosterone antagonism has emerged as an important strategy for end-stage congestive heart failure. To evaluate the potential contribution of aldosterone towards the cardiac complications of diabetes, this study examined the effects of chronic aldosterone receptor blockade (with spironolactone) on isolated working heart function in streptozotocin (STZ) - induced diabetic rats. Wistar rats were divided into four groups: control, control spironolactone-treated, diabetic, and diabetic spironolactone-treated. Following chronic spironolactone treatment (8 weeks), cardiac function was assessed in terms of the rate of contraction (+dP/dT), rate of relaxation (–dP/dT), and left ventricular developed pressure (LVDP). Untreated diabetic rats exhibited marked cardiac dysfunction when compared with age matched controls (p < 0.001). Long-term spironolactone treatment did not improve these parameters. These data demonstrate the lack of beneficial effects of aldosterone receptor blockade on isolated working heart function in diabetes.Key words: aldosterone, streptozotocin-induced diabetes, aldosterone receptor blocker, spironolactone, cardiac function.

1986 ◽  
Vol 251 (3) ◽  
pp. H571-H580 ◽  
Author(s):  
B. Rodrigues ◽  
J. H. McNeill

The isolated perfused working heart was used to study hypertensive diabetes-induced alterations in cardiac function at 6 and 12 wk after diabetes was induced. At 6 wk after diabetes induction, cardiac performance was depressed in the diabetic animals. However, there was no difference in cardiac function between normotensive Wistar and spontaneously hypertensive (SHR) diabetic rats. Wistar-Kyoto (WKY) rats were also included as normotensive controls in our 12-wk study. Hearts from 12-wk SHR and Wistar diabetic animals exhibited a depressed left ventricular developed pressure and positive and negative dP/dt when compared with control animals. However, this depression was not seen in the WKY diabetic animals. In addition, quantitation of various parameters of heart function revealed highly significant differences between SHR diabetic animals and all other groups associated with an increased mortality. Serum lipids were elevated in SHR and Wistar and were unaffected in WKY diabetic rats. Furthermore, thyroid hormone levels were not depressed in WKY diabetic rats as seen in the other two diabetic groups. This normal lipid metabolism and thyroid status could, in part, explain the lack of cardiac dysfunction in these animals. The data provide further evidence that the combination of hypertension and diabetes mellitus produces greater myocardial dysfunction than with either disease alone and is associated with a significant mortality.


1994 ◽  
Vol 72 (5) ◽  
pp. 447-455 ◽  
Author(s):  
Brian Rodrigues ◽  
Paul F. Grassby ◽  
Mary L. Battell ◽  
Stephanie Y. N. Lee ◽  
John H. McNeill

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.


1999 ◽  
Vol 86 (3) ◽  
pp. 812-818 ◽  
Author(s):  
Kiminori Kato ◽  
Donald C. Chapman ◽  
Heinz Rupp ◽  
Anton Lukas ◽  
Naranjan S. Dhalla

To examine the role of changes in myocardial metabolism in cardiac dysfunction in diabetes mellitus, rats were injected with streptozotocin (65 mg/kg body wt) to induce diabetes and were treated 2 wk later with the carnitine palmitoyltransferase inhibitor (carnitine palmitoyltransferase I) etomoxir (8 mg/kg body wt) for 4 wk. Untreated diabetic rats exhibited a reduction in heart rate, left ventricular systolic pressure, and positive and negative rate of pressure development and an increase in end-diastolic pressure. The sarcolemmal Na+-K+-ATPase activity was depressed and was associated with a decrease in maximal density of binding sites (Bmax) value for high-affinity sites for [3H]ouabain, whereas Bmax for low-affinity sites was unaffected. Treatment of diabetic animals with etomoxir partially reversed the depressed cardiac function with the exception of heart rate. The high serum triglyceride and free fatty acid levels were reduced, whereas the levels of glucose, insulin, and 3,3′,-5-triiodo-l-thyronine were not affected by etomoxir in diabetic animals. The activity of Na+-K+-ATPase expressed per gram heart weight, but not per milligram sarcolemmal protein, was increased by etomoxir in diabetic animals. Furthermore, Bmax (per g heart wt) for both low-affinity and high-affinity binding sites in control and diabetic animals was increased by etomoxir treatment. Etomoxir treatment also increased the depressed left ventricular weight of diabetic rats and appeared to increase the density of the sarcolemma and transverse tubular system to normalize Na+-K+-ATPase activity. Therefore, a shift in myocardial substrate utilization may represent an important signal for improving the depressed cardiac function and Na+-K+-ATPase activity in diabetic rat hearts with impaired glucose utilization.


1990 ◽  
Vol 68 (4) ◽  
pp. 514-518 ◽  
Author(s):  
Brian Rodrigues ◽  
John H. McNeill

The purpose of this investigation was to examine cardiac function and biochemistry in spontaneously diabetic BB rats, a strain in which diabetes occurs spontaneously and closely resembles insulin-dependent diabetes in humans. The study involved two groups: nondiabetic littermates of BB rats and BB diabetic rats treated daily with a very low insulin dose such that the rats were severely hyperglycemic and hyperlipidemic. The hearts from these two groups were isolated and heart function (using isolated perfused working hearts) and biochemistry were examined 6 weeks after the onset of diabetes. BB diabetic rats exhibited a lower calcium-stimulated myosin ATPase activity and depressed left ventricular developed pressure, cardiac contractility, and ventricular relaxation rates compared with BB nondiabetic littermates. These results suggest that the chronically diabetic state in the BB rat produces cardiac changes similar to those demonstrable after chemical diabetes induced by alloxan or STZ, or that seen during human diabetes mellitus.Key words: diabetes, cardiac function, Wistar BB rat, myosin ATPase, cardiomyopathy.


2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Emiliano Medei ◽  
Gustavo Monnerat Cahli ◽  
Mayra Trentin-Sonoda ◽  
Deivid Rodrigues ◽  
Bárbara Guerra ◽  
...  

Cardiac complications are one of the main causes of death in diabetes. Several studies have shown the anti-diabetic effects of bone marrow mesenchymal stromal cells (MSC). In the present study, we investigated whether MSC-transplantation can revert cardiac dysfunction in streptozotocin-induced diabetic rats and the immunoregulatory effects of MSC were examined. The rats were divided in three groups: Non-diabetic, Diabetic and Diabetic-Treated that received 5x106 MSC 4 weeks after establishment of diabetes. Four weeks after MSC-therapy, systemic metabolic parameters, immunological profile and cardiac function were assessed. MSC-transplantation was able to revert the hyperglycemia and body weight loss of the animals, while decreasing to control levels sera corticosterone and the proinflammatory cytokine CINC2 without restoring insulin and leptin plasma levels and oral glucose tolerance. Also, MSC-therapy improved electrical remodeling, shortening the QT and QTc in the ECG and the action potential duration of left ventricular myocytes. No arrhythmic events were observed after MSC-transplantation. MSC-therapy rescued the cardiac beta-adrenergic sensitivity by increasing beta-1 adrenergic receptor expression. Both alpha and beta cardiac AMPK and p-AMPK returned to baseline values after MSC-therapy. However, the total ERK1 and p-ERK1/2 were not different among groups. MSC-therapy reestablished the cardiac control levels of key proinflammatory cytokines/chemokines (IL-6, IL-18, CINC2, CINC3). However MSC-therapy did not modulate toll-like receptor signaling pathways. The results indicate that MSC-therapy was able to rescue cardiac impairment induced by diabetes, normalize cardiac AMPK subunit expression and activity, decrease corticosterone and glycemia and exert local (cardiac) and systemic immunoregulation.


2019 ◽  
Vol 21 (7) ◽  
pp. 862-873 ◽  
Author(s):  
Salva R. Yurista ◽  
Herman H.W. Silljé ◽  
Silke U. Oberdorf‐Maass ◽  
Elisabeth‐Maria Schouten ◽  
Mario G. Pavez Giani ◽  
...  

1993 ◽  
Vol 71 (3-4) ◽  
pp. 270-276 ◽  
Author(s):  
Violet G. Yuen ◽  
Chris Orvig ◽  
Katherine H. Thompson ◽  
John H. McNeill

Decreased cardiac function in streptozotocin-diabetic rats has been used as a model of diabetes-induced cardiomyopathy, which is a secondary complication in diabetic patients. The present study was designed to evaluate the therapeutic effect of a new organic vanadium complex, bis(maltolato)oxovanadium(IV), (BMOV), in improving heart function in streptozotocin-diabetic rats. There were four groups of male, Wistar rats: control (C), control treated (CT), diabetic (D), and diabetic treated (DT). Treatment consisted of BMOV, 0.5 mg/mL (1.8 mM) for the first 3 weeks and 0.75 mg/mL (2.4 mM) for the next 22 weeks, in the drinking water of rats allowed ad libitum access to food and water. BMOV lowered blood glucose to < 9 mM in 70% of DT animals without any increase in plasma insulin levels, and mean blood glucose and plasma lipid levels were significantly lower in DT vs. D rats. Tissue vanadium levels were measured in plasma, bone, kidney, liver, muscle, and fat of BMOV-treated rats. Plasma vanadium levels averaged 0.84 ± 0.07 μg/mL (16.8 μM) in CT rats and 0.76 ± 0.05 μg/mL (15.2 μM) in DT animals. The highest vanadium levels at termination of this chronic feeding study were in bone, 18.3 ± 3.0 μg/g (0.37 μmol/g) in CT and 26.4 ± 2.6 μg/g (0.53 μmol/g) in DT rats, with intermediate levels in kidney and liver, and low, but detectable levels in muscle and fat. There were no deaths in either the CT or DT group, and no overt signs of vanadium toxicity were present. Tissue vanadium levels were not correlated with the glucose-lowering effect. Isolated working heart parameters of left ventricular developed pressure (LVDP) and rate of pressure development (+dP/dT, and −dP/dT) indicated that BMOV treatment resulted in significant correction of the heart dysfunction associated with streptozotocin-induced diabetes in rat.Key words: bis(maltolato)oxovanadium(IV), vanadium, diabetes, streptozotocin, myocardial dysfunction.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Xing Yin ◽  
Melanie R. Moody ◽  
Valeria Hebert ◽  
Melvin E. Klegerman ◽  
Yong-Jian Geng ◽  
...  

Abstract Cardiac hypertrophy often causes impairment of cardiac function. Xenon (Xe), a naturally occurring noble gas, is known to provide neurological and myocardial protection without side effects. The conventional method of Xe delivery by inhalation is not feasible on a chronic basis. We have developed an orally deliverable, effective Xe formulation for long-term administration. We employed 2-hydroxypropyl)-β-cyclodextrin (HPCD), which was dissolved in water to increase the Xe concentration in solution. The beneficial effects of long-term oral administration of Xe-enriched solutions on cardiovascular function were evaluated in vivo. HPCD increased Xe solubility from 0.22 mM to 0.67 mM (3.8-fold). Aged ApoE knockout mice fed high-fat diet for 6 weeks developed hypertension, and myocardial hypertrophy with impaired cardiac function. Oral Xe prevented this ischemic damage, preserving normal blood pressure, while maintaining normal left ventricular mass and wall thickness. This novel formulation allows for gastrointestinal delivery and cardiovascular stabilization.


2014 ◽  
Vol 115 (suppl_1) ◽  
Author(s):  
Yigang Wang

Objective: We sought to assess the cardiac protective effects after MI of (1) PC differentiated directly into cardiomyocytes (CM) and endothelial cells (EC) to the site of injury, or (2) paracrine factors released from PC. Methods: These concepts were evaluated by using iPSC-derived PC genetically modified to express the herpes simplex virus thymidine kinase (TK) under the control of cardiomyocyte (NCX1) or endothelial cell (VE-cadherin) specific promoters. PC expressing the TK permitted ablation at the first week or the third week by iv ganciclovir (GCV). If GCV applied at the first week, but not at the third week, altered cardiac function, we would conclude that myocardial contractile recovery depends on CM and EC-derived from iPSC. If the beneficial effects on cardiac function persisted after GCV was given at the third week, we would surmise that the PC effect was via by a paracrine action. MI created by ligation of LAD, the cell patch with PC was applied to the scarred myocardium. Rats were treated with GCV at 1 or 3 weeks to ablate implanted PC. Echocardiography, vessel density, and histological analysis were used to obtain endpoints for this study. Result: In vivo : The levels of IGF-1α and VEGF released from ischemic tissues were significant higher in the cell patch group. Heart function, infarction size, and vessel density were significantly improved after cell patch treatment. However, this beneficial effect on cardiac function was completely abolished in the group given GCV at week 1, but only partially abolished in the group given GCV at week 3 compared to the untreated cell patch group. Conclusions: Taken together, these data support our conclusion that iPSC-derived cardiovascular lineages (CM and EC) contribute directly to an improved cardiac performance and attenuated remodeling, and that paracrine factors also play a supporting role in the restoration of heart function after MI.


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