Autologous mesenchymal stem cell implantation promotes myocardial expressions of growth factors and improves cardiac function in failing rat hearts / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the underlying mechanism of mesenchymal stem cells (MSCs) transfer induced cardiac function improvement in failing hearts.</p><p><b>METHODS</b>Congestive heart failure (CHF) was induced in rats by cauterization of the heart wall. MSCs were cultured from autologous bone marrow and injected into the border zone and the remote myocardium 5 days after cauterization.</p><p><b>RESULTS</b>Ten weeks later, cardiomyocyte nucleus mitotic index, capillary density and expression of insulin-like growth factor 1 (IGF-1), hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) were significantly increased in the border zone and significantly reduced in the remote myocardium in CHF rats (all P<0.05 vs. sham). Besides cardiac function improvement and left ventricular remodeling attenuation evidenced by hemodynamic and echocardiographic examinations, expressions of IGF-1, HGF and VEGF in the remote myocardium and in the border zone were also significantly upregulated (P<0.05 or P<0.01 vs. CHF), and cardiomyocyte nucleus mitotic index as well as capillary density were significantly increased in CHF rats with MSCs (P<0.05 or P<0.01 vs. CHF). Moreover, collagen area was significantly reduced and myocardial area was significantly increased in the border zone in these rats too.</p><p><b>CONCLUSION</b>Autologous MSC implantation upregulated expressions of growth factors enhanced cardioangiogenesis which might be the underlying mechanisms for improved cardiac function and attenuated left ventricular remodeling induced by MSCs transplantation in failing rat myocardium.</p>

Cell therapy in congestive heart failure / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Congestive heart failure (CHF) has emerged as a major worldwide epidemic and its main causes seem to be the aging of the population and the survival of patients with post-myocardial infarction. Cardiomyocyte dropout (necrosis and apoptosis) plays a critical role in the progress of CHF; thus treatment of CHF by exogenous cell implantation will be a promising medical approach. In the acute phase of cardiac damage cardiac stem cells (CSCs) within the heart divide symmetrically and/or asymmetrically in response to the change of heart homeostasis, and at the same time homing of bone marrow stem cells (BMCs) to injured area is thought to occur, which not only reconstitutes CSC population to normal levels but also repairs the heart by differentiation into cardiac tissue. So far, basic studies by using potential sources such as BMCs and CSCs to treat animal CHF have shown improved ventricular remodelling and heart function. Recently, however, a few of randomized, double-blind, placebo-controlled clinical trials demonstrated mixed results in heart failure with BMC therapy during acute myocardial infarction.

Combined effects of ramipril and angiotensin II receptor blocker TCV116 on rat congestive heart failure after myocardial infarction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Congestive heart failure (CHF) is a major cause of morbidity and mortality worldwide and angiotensin converting-enzyme inhibitor (ACEI) is the cornerstone in its treatment. However, CHF continues to progress despite this therapy, perhaps because of production of angiotensin II (Ang II) by alternative pathways. The present study was conducted to examine the combined effects of a chronic ACEI, ramipril, and a chronic Ang II type 1 receptor blocker, TCV116, on rat CHF after myocardial infarction (MI).</p><p><b>METHODS</b>Congestive heart failure was caused by MI in rats, which was induced by ligating the left anterior descending coronary artery. The experiment protocol included sham-operated rats (Sham), MI-control rats (MI-control), MI rats treated with ramipril 3 mg/kg (MI-ramipril) or TCV116 2 mg/kg (MI-TCV116) per day, half dosage (MI-1/2R&T) or full dosage (MI-R&T) combination of the two. At 22 weeks, cardiac hemodynamic parameters such as mean arterial pressure (MAP), left ventricular systolic pressure (LVSP), maximal rate of left ventricule pressure development and decline (LV dP/dtmax) and left ventricular end diastolic pressure (LVEDP), and cardiac morphometric parameters such as heart weight (HW), left ventricular weight (LVW) and left ventricular cavity area (LVCA) were measured, mRNA expressions of cardiac molecule genes such as beta myosin heavy chain (betaMHC), B-type natriuretic peptide (BNP), transforming growth factor-beta1 (TGF-beta1), collagen I and III were quantified with reverse transcription polymerase chain reaction (RT-PCR) in the surviving septum myocardium, and survival rates were calculated.</p><p><b>RESULTS</b>There were no significant differences in MI sizes (%) among each MI related experimental groups (33 +/- 13, 34 +/- 14, 33 +/- 13, 35 +/- 13 and 33 +/- 14 for MI-control, MI-ramipril, MI-TCV116, MI-1/2R&T and MI-R&T, respectively, no statistical significance for all). Compared with sham-operated rats, MI rats without therapy showed significant increases in morphometric parameters as well as in mRNA expressions of cardiac molecule genes (P < 0.01); while their hemodynamic parameters were significantly impaired (P < 0.01), and in terms of spontaneous deaths survival rate shortened (P < 0.05). Compared with MI rats without therapy, MI rats treated with each single drug showed significant attenuation of mRNA expressions of cardiac molecule genes (P < 0.01); while their hemodynamic parameters were significantly improved (P < 0.05 or P < 0.01), and in terms of spontaneous deaths survival rate prolonged (P < 0.05). Both half and full dosage combined treatments exerted more powerful effects on improvement of cardiac phenotypic changes and on attenuation of betaMHC, BNP mRNA expressions (P < 0.05 vs monotherapy); while LVEDP was further lowered (P < 0.05 vs monotherapy). However, the total death in MI rats with full dosage combined treatment was more though there were no significant differences when compared with other treatments.</p><p><b>CONCLUSIONS</b>The results suggest that treatment with appropriate dosage combination of a chronic ACEI and a chronic ARB may further improve cardiac remodeling and cardiac function after MI.</p>

Long-term effects of TCV116 on cardiac function changes after myocardial infarction / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the long-term effects of TCV116 (candesartan cilexetil) on cardiac function changes after myocardial infarction.</p><p><b>METHODS</b>Myocardial infarction (MI) was induced by ligation of the left anterior descending coronary artery in rats. One week after the surgical performance,the surviving rats were randomly assigned to the following treatment groups: (1) MI rats with no therapy; (2) MI rats treated with TCV116 2 mg/kg per day; (3) Sham-operated control and (4) Sham-operated rats treated with TCV116 2 mg/kg per day. At 22 weeks, left ventricular function and cardiac histomorphometric parameters were measured, mRNA expression of cardiac genes such as beta myosin heavy chain, B-type natriuretic peptide, transforming growth factor beta1, collagen I and III quantified, and survival rates calculated.</p><p><b>RESULTS</b>Treatment with TCV116 significantly improved LV function, suppressed mRNA expression of cardiac genes,and extended the survival period compared with MI rats with no therapy (P<0.05).</p><p><b>CONCLUSION</b>Treatment with long-term angiotensin II type 1 receptor blocker may improve LV function and prolong the survival of rats after MI.</p>