Number Of Apoptotic Myocardial Cells Research Articles

ASCs-EVs Inhibit Apoptosis and Promote Myocardial Function in the Infarcted Heart via miR-221.

Extracellular vehicles (EVs) secreted from adipose-derived stem cells (ASCs) (ASCs-EVs) have the potential to treat myocardial infarction (MI), although the underlying mechanism remains unclear. The current study explored the ability of ASCs-EVs to inhibit apoptosis and promote myocardial function in the infarcted heart via microRNAs (miRNAs)-221. In hypoxia-induced H9C2 cells, a cardiac cell strain derived from the SD Rat left ventricle, we measured the cell viability and apoptosis-related protein expression after transfection with the ASCs-EVs-NC (negative control for EVs-miR-221) or ASCs-EVs-miR-221 mimics. We then verified the cardioprotective effects of miR-221-overexpressing ASCs-EVs by investigating myocardial cell apoptosis and cardiac function in a MI rat model treated with ASCs-EVs from miR-221-overexpressing ASCs by comparing control with ASC treatment. The in vitro experiment results showed that the proliferation of H9C2 cells and the anti-apoptotic protein expression were significantly enhanced by the ASCs-EVs-miR-221 mimic. The in vivo experiment results found that ASCs-EVs from miR-221-overexpressing ASCs have cardioprotective effects, as demonstrated by lower serum troponin levels and left ventricular end-systolic volume, and a lower number of apoptotic myocardial cells than those in control and ASC-treated rats. ASCs-EVs have therapeutic effects on MI by inhibiting cardiomyocyte apoptosis via miR-221.

Allisartan isoproxil attenuates oxidative stress and inflammation through the SIRT1/Nrf2/NF‑κB signalling pathway in diabetic cardiomyopathy rats.

Allisartan isoproxil is a new nonpeptide angiotensin II receptor blocker (ARB) precursor drug that is used to treat hypertension and reduce the risk of heart disease. The present study explored the effects of allisartan isoproxil on diabetic cardiomyopathy (DCM) and revealed the roles of hyperglycaemia-induced oxidative stress and inflammation. A rat DCM model was established by high-fat diet feeding in combination with intraperitoneal injection of streptozocin. Echocardiographs showed that diabetic rats exhibited significantly decreased cardiac function. Troponin T (cTnT) and B-type natriuretic peptide (BNP) were significantly increased in DCM rats as obtained by ELISA. Allisartan isoproxil significantly improved the EF% and E™/A™ ratio. Histopathologic staining showed that allisartan isoproxil prevented histological alterations, attenuated the accumulation of collagen, and ameliorated cTnT and BNP levels. Western blot and immunohistochemical results indicated that the expression levels of silent information regulator 2 homologue 1 (SIRT1) and nuclear factor erythroid 2-related factor 2 (Nrf2) were decreased in the hearts of diabetic rats, and antioxidant defences were also decreased. In addition, allisartan isoproxil decreased the expression of NF-κB p65 and the inflammatory cytokines TNF-α and IL-1β which were determined by reverse transcription-quantitative PCR in the diabetic heart. Western blotting and TUNEL staining results also showed that cardiac Bax and cleaved caspase-3 and the number of apoptotic myocardial cells were increased in the diabetic heart and decreased following treatment with allisartan isoproxil. In conclusion, the present results indicated that allisartan isoproxil alleviated DCM by attenuating diabetes-induced oxidative stress and inflammation through the SIRT1/Nrf2/NF-κB signalling pathway.

Interleukin-35 pretreatment attenuates lipopolysaccharide-induced heart injury by inhibition of inflammation, apoptosis and fibrotic reactions

Previous studies have demonstrated that targeting inflammation is a promising strategy for treating lipopolysaccharide (LPS)-induced sepsis and related heart injury. Interleukin-35 (IL-35), which consists of two subunits, Epstein–Barr virus-induced gene 3 (EBI3) and p35, is an immunosuppressive cytokine of the IL-12 family and exhibits strong anti-inflammatory activity. However, the role of IL-35 in LPS-induced heart injury reains obscure. In this study, we explored the role of IL-35 in heart injury induced by LPS and its potential mechanisms. Mice were treated with a plasmid encoding IL-35 (pIL-35) and then injected intraperitoneally (ip) with LPS (10 mg/kg). Cardiac function was assessed by echocardiography 12 h later. LPS apparently decreased the expression of EBI3 and p35 and caused cardiac dysfunction and pathological changes, which were significantly improved by pIL-35 pretreatment. Moreover, pIL-35 pretreatment significantly decreased the levels of cardiac proinflammatory cytokines including TNF-α, IL-6, and IL-1β, and the NLRP3 inflammasome. Furthermore, decreased number of apoptotic myocardial cells, increased BCL-2 levels and decreased BAX levels inhibited apoptosis, and LPS-induced upregulation of the expression of cardiac pro-fibrotic genes (MMP2 and MMP9) and fibrotic factor (Collagen type I) was inhibited. Further investigation indicated that pIL-35 pretreatment might suppressed the activation of the cardiac NF-κBp65 and TGF-β1/Smad2/3 signaling pathways in LPS-treated mice. Similar cardioprotective effects of IL-35 pretreatment were observed in mouse myocardial fibroblasts challenged with LPS in vitro. In summary, IL-35 pretreatment can attenuate cardiac inflammation, apoptosis, and fibrotic reactions induced by LPS, implicating IL-35 as a promising therapeutic target in sepsis-related cardiac injury.

Effects of Promethazine on Proliferation and Apoptosis of Myocardial Cells in Rats with Myocardial Ischemia-Reperfusion Injury Through PI3K/Akt Signaling Pathway

Objective: To assess promethazine's effect on myocardial cells in rats with myocardial ischemiareperfusion injury (MIRI). Methods: The rat MIRI model was established and treated as the ischemia group. MIRI rats were treated with promethazine and included as the drug group. Rats only undergoing thoracotomy were enrolled as the control group. The physiological function of heart was assessed using the ultrasound cardiotachograph, and the apoptosis and proliferation of myocardial cells were detected using TUNEL assay and Ki67 staining, respectively. Moreover, the expressions of Caspase-3, Bcl-2, PI3K, GSK-3, PDK-1 and PKB were determined via Western blotting and qPCR. Results: There were significant differences in cardiac function indexes [left ventricular enddiastolic diameter (LVEDd), left ventricular end systolic diameter (LVESd), ejection fraction (EF) and fractional shortening (FS)] among the three groups (p= 0 002, 0.004, 0.025 and 0.012), and ischemia group had the highest LVEDd [(8.73± 0.31) mm] and LVESd [(7.98± 0.37) mm] and lowest EF [(42± 3.8)%] and FS [(40.3± 2.8)%]. The number of apoptotic myocardial cells was significant higher in ischemia group than control ( p< 0 05), while it was significantly declined after treatment with promethazine ( p< 0 05). Caspase-3 was significantly upregulated and Bcl-2 was downregulated in ischemia group which were all significantly reversed in drug group. Besides, Ki67 level was significantly reduced in ischemia group compared to control and higher in drug group than ischemia group, indicating that drug treatment increased cell proliferation ability. The levels of PI3K, GSK-3 and PKB in myocardial tissues were significantly declined in ischemia group and elevated after the treatment with promethazine without difference of PDK-1 level in myocardial tissues among the three groups. Conclusion: Promethazine inhibits apoptosis and promotes proliferation of myocardial cells in MIRI rats through PI3K/Akt signaling pathway.

Losartan promotes myocardial apoptosis after acute myocardial infarction in rats through inhibiting Ang II-induced JAK/STAT pathway.

To study the pro-apoptotic effect of Losartan on myocardial cells after acute myocardial infarction (AMI) in rats. Before intervention, a total of 48 male Wistar rats were randomly divided into the Sham group (n=12), AMI group (n=12), 5 mg/kg Losartan group (n=12) and 1 mg/kg AG-490 group (n=12). The rats in the Sham group and AMI group received gavage with normal saline, those in the Losartan group received gavage with Losartan for 7 d and those in the AG-490 group were intravenously injected with AG-490 at 30 min before the operation. At 4 d after drug administration, the anterior descending coronary artery was ligated to establish the AMI model in the AMI group and Losartan group, while the same operation was performed, and the anterior descending coronary artery was only threaded in the Sham group. The rats were sacrificed at 24 h after operation. Then, the myocardial apoptosis was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the protein expressions of Janus kinase 2 (JAK2), the signal transducer and activator of transcription 3 (STAT3), the B-cell lymphoma-2 (Bcl-2) and the Bcl-2 associated X protein (Bax) were detected via immunohistochemistry and Western blotting. Moreover, the myocardial cells of rats were incubated with angiotensin II (Ang II) at the same concentration at different time points and blocked with Losartan. Finally, the changes in protein expressions of p-JAK2, p-STAT3, Bax, and Bcl-2 were detected via Western blotting. Losartan treatment could increase the number of apoptotic myocardial cells after AMI in rats. In Losartan group, the protein expressions of JAK2, STAT3, and Bcl-2 declined, while the protein expression of Bax was increased, and the Bax/Bcl-2 ratio was also increased, which are consistent with the conditions under the treatment with the JAK-STAT pathway inhibitor AG-490. With the prolonged time of stimulation (5 min, 30 min, 2 h, and 24 h) in myocardial cells using 1.0×10-6 mol/L Ang II, the protein expressions of p-JAK2 and p-STAT3 were increased and reached the peak at 24 h. After the application of Losartan, the increased protein expressions of p-JAK2 and p-STAT3 returned to normal levels, and the protein expression of Bax was increased, while that of Bcl-2 was decreased. Losartan promotes myocardial apoptosis after AMI in the rats through inhibiting the Ang II-induced JAK/STAT pathway.

Perindopril inhibits myocardial apoptosis in mice with acute myocardial infarction through TLR4/NF-κB pathway.

To explore the anti-apoptotic effect of perindopril on myocardial cells in mice with acute myocardial infarction (AMI). A total of 48 mice were randomly divided into 4 groups before intervention, namely sham operation group (Sham group, n=12), AMI group (n=12), 1.5 mg/kg perindopril treatment group (Perindopril group, n=12), and 1.5 mg/kg perindopril treatment and Toll-like receptor-4 (TLR4) knockout group (TLR4-/-Perindopril group, n=12). Mice in the control group and AMI group were gavaged with normal saline, and those in the Perindopril group and TLR4-/-Perindopril group were gavaged with perindopril for 7 d. On the 4th day after drug administration, mice in the AMI group, Perindopril group and TLR4-/-Perindopril group were subjected to the ligation of the anterior descending coronary artery to induce AMI, and those in the Sham group underwent the same operation, but had a loose knot at the anterior descending coronary artery. At 24 h after the above operation, color echocardiography was performed on mice to observe changes in cardiac function. Then, the mice were sacrificed. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick end labeling (TUNEL) assay was carried out to determine myocardial apoptosis. Immunohistochemistry and Western blotting technique were employed to detect the protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), TLR4 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p50 in infarction zones. The messenger ribonucleic acid (mRNA) expression levels of TLR4 and NF-κB p50 in infarction zones were measured via Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Perindopril could significantly reduce the number of apoptotic myocardial cells after AMI. Mouse echocardiography showed that ejection fraction (EF), left ventricular fractional shortening (FS), left ventricular end-systolic diameter (LVESD) and left ventricular end-diastolic diameter (LVEDD) of AMI mice in the Perindopril groups were markedly superior to those in the AMI group. AMI mice in the Perindopril group had decreased expression levels of Bax protein and TLR4 and NF-κB p50 mRNA and protein, as well as the Bax/Bcl-2 ratio. Knockout of TLR4 attenuated the effect of perindopril in alleviating myocardial apoptosis after AMI. Perindopril inhibits myocardial apoptosis in mice with AMI through the TLR4/NF-κB pathway.

Effect of IL-6-mediated STAT3 signaling pathway on myocardial apoptosis in mice with dilated cardiomyopathy.

To investigate the effect of interleukin-6 (IL-6) gene knockout on apoptosis of myocardial cells in mice with Coxsackievirus B3 (CVB3)-induced dilated cardiomyopathy (DCM) and its potential mechanism, so as to provide certain references for the clinical prevention and treatment of DCM. A total of 40 male C57 mice were randomly divided into Sham group (n=20) and DCM group (n=20) using a random number table. Another 20 mice with IL-6 gene knockout were enrolled into DCM+IL-6 KO group (n=20). The DCM model was established via CVB3 repeated incremental infection. After 9 months, the heart weight/body weight (HW/BW) ratio of mice in each group was detected. The ejection fraction [EF (%)] and fraction shortening [FS (%)] of mice in each group were detected via two-dimensional ultrasonography. The cross-sectional area and pathological changes in myocardial cells in the heart in each group were determined using hematoxylin-eosin (HE) staining. The collagen content in myocardial tissues in each group was detected via Masson staining and picrosirius red (PSR) staining, and the expressions of Collagen I and Collagen III in myocardial tissues in each group were detected via immunohistochemistry. In addition, the myocardial apoptosis in myocardial tissues in each group was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Finally, the protein expression levels of B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), and total STAT3 (t-STAT3) were detected via Western blotting. The expression of IL-6 messenger ribonucleic acids (mRNAs) in myocardial tissues in DCM group was significantly increased compared with that in Sham group (p<0.05). After IL-6 knockout, the HW/BW ratio of DCM mice significantly declined (p<0.05), and the cross-sectional area of myocardial cells was significantly reduced (p<0.05). According to the results of echocardiography, the cardiac function of mice in DCM+IL-6 KO group was significantly superior to that in DCM group, manifested as the significant increase in FS (%) and EF (%) (p<0.05). The results of Masson staining, PSR staining, and immunohistochemical staining showed that IL-6 knockout could reduce the collagen content and Collagen I and Collagen III expressions in myocardial tissues of DCM mice (p<0.05). Furthermore, it was found via TUNEL staining that the number of apoptotic myocardial cells in DCM+IL-6 KO group was markedly smaller than that in DCM group (p<0.05). At the same time, the Bax/Bcl-2 ratio in myocardial tissues in DCM+IL-6 KO group was lower (p<0.05). Finally, the results of Western blotting revealed that DCM+IL-6 KO group had a lower phosphorylation level of STAT3 than DCM group (p<0.05). Inhibiting IL-6 gene may improve the DCM-induced myocardial remodeling through reducing myocardial apoptosis.

Influence of MiR-154 on myocardial apoptosis in rats with acute myocardial infarction through Wnt/β-catenin signaling pathway.

To explore the influence of micro ribonucleic acid (miR)-154 on myocardial apoptosis in rats with acute myocardial infarction (AMI), and to analyze whether Wnt/β-catenin signaling pathway was involved in the regulation. The Sprague-Dawley (SD) rat model of AMI was established via ligation of left anterior descending artery. Rats were randomly divided into model group (M group, n=12) and ICG-001 intervention group (I group, n=12). At the same time, sham operation group (S group, n=12) was established. In I group, ICG-001 (5 mg/kg) was intraperitoneally injected every day after operation. Meanwhile, an equal amount of normal saline was injected in rats of S group and M group. 21 d after operation, the cardiac function of rats in each group was detected via echocardiography. After that, the rats were immediately executed. MI area in each group was detected via 2,3,5-triphenyltetrazolium chloride (TTC) staining. Myocardial apoptosis level in each group was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Moreover, the changes of apoptotic proteins in rat myocardial cells were detected via Western blotting. Moreover, the expression level of miR-154 in myocardial cells of rats was detected via quantitative polymerase chain reaction (qPCR). Furthermore, the influence of miR-154 on Wnt/β-catenin signaling pathway was detected via Western blotting. Compared with S group, left ventricular ejection fraction (LVEF, %) and left ventricular fractional shortening (LVFS, %) were significantly decreased in M group (p<0.01). However, left ventricular internal diameter at end-diastole (LVIDd) and left ventricular internal diameter at end-systole (LVIDs) were significantly increased (p<0.01). In I group, LVEF (%) and LVFS (%) were significantly higher than those of M group (p<0.05), whereas LVIDs and LVIDd were significantly lower (p<0.05). MI area in M group was remarkably larger than that of S group (p<0.01). Meanwhile, MI area in I group was significantly smaller than that of M group (p<0.01). Compared with S group, the number of apoptotic myocardial cells and the protein expression level of cleaved caspase-3 were significantly increased in M group (p<0.01). However, the expression level of B-cell lymphoma-2/Bcl-2 associated X protein (Bcl-2/Bax) was significantly decreased (p<0.01). The number of apoptotic myocardial cells and the protein expression level of cleaved caspase-3 were significantly declined in I group when compared with those of M group (p<0.01). However, the expression level of Bcl-2/Bax was significantly increased in I group (p<0.01). The expression level of miR-154 in myocardial cells of M group and I group was remarkably increased when compared with that of S group (p<0.01). Furthermore, the expression levels of β-catenin and Cyclin D1 in myocardial cells of M group were remarkably higher than those of S group and I group (p<0.01). AMI significantly increases the expression level of miR-154. Moreover, miR-154 can activate Wnt/β-catenin signaling pathway, eventually promoting myocardial apoptosis.

Delivery of biotinylated IGF-1 with biotinylated self-assembling peptides combined with bone marrow stem cell transplantation promotes cell therapy for myocardial infarction.

Cell therapy is a promising approach for cardiac repair. The aim of the present study was to determine the feasibility of using biotinylated insulin-like growth factor 1 (IGF-1) with biotinylated self-assembling peptides (tethered IGF-1) combined with bone marrow stem cells (BMSCs) transplantation for the treatment of heart failure. Tethered IGF-1 was synthesized and its effect on H9c2 cells was analyzed. Reverse transcription-quantitative polymerase chain reaction and western blot assays demonstrated that tethered IGF-1 did not significantly affect the expression and phosphorylation of AKT, whereas it significantly increased the expression of cardiac troponin T (P<0.01). A rabbit myocardial infarction model was constructed and rabbits were divided into four groups: Control group (no treatment), group 1 (G1; BMSC transplantation), group 2 (G2; BMSCs + non-biotinylated IGF-1) and group 3 (G3; BMSCs + tethered IGF-1). At 4 weeks after modeling, cardiac tissues were obtained for analysis. In the control group, myocardial fibers were disordered, a large number of inflammatory cells infiltrated the cardiac tissues, and apoptosis occurred in ~50% of cells. However, in G1, G2 and G3, muscle cells were well ordered, and a lesser degree of myocardial degeneration and inflammatory cell infiltration was observed. Compared with the control group, the apoptosis rates of myocardial cells in G1-G3 were significantly decreased (P<0.01). Furthermore, compared with G1 and G2, tissue morphology was improved in G3and the number of apoptotic myocardial cells was significantly decreased (P<0.01). These results suggest that treatment with tethered IGF-1 + BMSCs significantly suppresses cell apoptosis and induces the expression of cardiac maturation proteins. These findings provide a novel insight into how the delivery of tethered IGF-1 with BMSCs could potentially enhance the prognosis of patients with heart failure treatment.

Effect and mechanism of propofol on myocardial ischemia reperfusion injury in type 2 diabetic rats

BackgroundPropofol has been reported to have an inhibitory effect on ischemia/reperfusion (I/R) injury in various experimental models by reducing oxidative stress, protecting mitochondrial function and suppressing apoptosis. The aim of this study was to investigate the effect and mechanism of propofol on myocardial I/R injury in type 2 diabetic rats. MethodsA total of 24 streptozotocin (STZ)-induced diabetic rats were randomly divided into three equal groups as follows: the DI group with myocardial I/R, which was induced by occluding the left anterior descending coronary artery for 30min, followed by 2h of reperfusion; the DP group, which underwent I/R and propofol infusion at 6mg·kg−1·h−1; and the DC group, which underwent sham operations without tightening of the coronary sutures. As a control, 24 healthy, age-matched, male Wistar rats were randomly divided into three equal groups: the CI, CP and CC groups. The injured cardiac tissues were removed for microscopic examination after reperfusion. The serum concentrations of nitric oxide (NO) and endothelin (ET-1); the expression of Bax, Bcl-2 and Caspase-3 within the cardiac structures; and the number of apoptotic myocardial cells were measured. ResultsCompared with the baseline levels before ischemia, the serum concentration of ET-1 after 2h of reperfusion was increased in the CI and DI groups, while the concentration of NO in these groups decreased after reperfusion. Compared with the I/R groups, propofol increased the content of NO and decreased the content of ET-1. Compared with the sham operation groups, I/R decreased the ratio of the anti-apoptotic protein Bcl-2 to the pro-apoptotic protein Bax, which resulted in an elevation of the index of apoptosis (AI). In contrast, compared with the I/R group, propofol increased the Bcl-2-to-Bax ratio and decreased the AI. I/R increased the expression of caspase-3 compared with the sham treatment groups, while treatment with propofol reduced caspase-3 expression relative to the I/R groups. ConclusionsThese data suggest that propofol can protect against myocardial ischemia–reperfusion injury in both normal and type 2 diabetic rats, possibly by attenuating endothelial cell injury and inhibiting the apoptosis of cardiomyocytes.

THE STUDY OF APOPTOSIS MECHANISM IN THE PROCESS OF RECOMBINANT INTERLEUKIN-12 TREAT THE MICE WITH VIRAL MYOCARDITIS

ObjectivesThrough studying the NK cell activity, the pathological changes of myocardial cells and the changes of apoptosis in the process of recombinant interleukin -12 treat the mice with viral myocarditis,...

Mechanisms of improvement of left ventricle remodeling by trans-planting two kinds of autologous bone marrow stem cells in pigs

The necrosis of a large number of myocardial cells after acute myocardial infarction (AMI) results in a decrease of cardiac function and ventricle remodeling. Stem cell transplantation could improve cardiac function after AMI, but the involving mechanisms have not been completely understood. The present study aimed to investigate the effects of transplantation of autologous bone marrow mononuclear cells (BM-MNC) and mesenchymal stem cells (MSCs) via the coronary artery on the ventricle remodeling after AMI as well as the mechanisms of the effects of transplantation of different stem cells on ventricle remodeling. A total of 36 male pigs were enrolled in this study, which were divided into 4 groups: control group, simple infarct model group, BM-MNC transplantation group, and MSCs transplantation group. At 90 minutes when a miniature porcine model with AMI was established, transplantation of autologous BM-MNC ((4.7 +/- 1.7) x 10(7)) and MSCs ((6.2 +/- 1.6) x 10(5)) was performed in the coronary artery via a catheter. Ultrasound, electron microscope, immunohistochemical examination and real time reverse transcriptase-polymerase chain reaction were used respectively to observe cardiac functions, counts of blood vessels of cardiac muscle, cardiac muscle nuclear factor (NF)-kappaB, myocardial cell apoptosis, and the expression of the mRNA of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in cardiac muscles. Multivariate Logistic regression was used to analyze the correlation factors of left ventricular end-diastolic diameter (EDD). The number of blood vessels in the infarct zone and around its border in the BM-MNC transplantation group was more than those in the infarct model group and MSCs group (P = 0.0001) and there was less myocardial cell apoptosis in the stem cell transplantation group than that in the infarct model group (all P < 0.01). The positive rate of NF-kappaB in the stem cell transplantation group was lower than that in the infarct model group (P = 0.001). The gene expression of VEGF in the infarct border zone of the BM-MNC group was higher than that in the MSCs group (P = 0.0001). The gene expression of bFGF in the infarct border zone in the MSCs transplantation group was higher than that in the infarct model group and the BM-MNC group (P = 0.0001). Left ventricular ejection fraction was inversely proportional to the apoptotic rate of myocardial cells and cardiac muscle NF-kappaB but positively correlated with the number of blood vessels and the expression of VEGF and bFGF in the infarct zone and infarct border zone. The Multivariate Logistic regression analysis on the factors influencing the left ventricular end-diastolic diameter after stem cell transplantation showed that the expression of VEGF mRNA in the cardiac muscles in the infarct zone, the number of apoptotic myocardial cells and the expression of NF-kappaB in the infarct border zone were independent factors for predicting the inhibitory effect on the dilation of left ventricular EDD after stem cell transplantation. Transplantation of autologous BM-MNC and MSCs in pigs can improve the condition of left ventricular remodeling and recover the cardiac functions after AMI. The improvement of cardiac functions is related to the increase of blood vessels, the increased expression of VEGF and bFGF, the reduction of myocardial cell apoptosis, and the decrease of NF-kappaB level in cardiac muscle tissues after stem cell transplantation.

Long‐term effect of gene therapy for chronic ischemic myocardium using platelet‐derived endothelial cell growth factor in dogs

We previously reported the 2-week benefits of platelet-derived endothelial cell growth factor (PD-ECGF) gene therapy in chronically ischemic myocardium. However, the long-term effects and safety using this gene have not been reported. Chronic myocardial ischemia was created in 24 dogs by stenosing the origin of the left anterior descending coronary artery (LAD) using an ameroid constrictor. Two weeks later, the PD-ECGF gene, the LacZ gene, or saline was infused directly into the myocardium in the LAD area. The myocardial blood volume and myocardial function were examined prior to ischemia, immediately before gene injection, and for 6 months following injection, and then the organs were harvested for histological and molecular examination. PD-ECGF gene treatment significantly attenuated endocardial infarction at 6 months. Myocardial blood volume and myocardial function decreased in all three groups after ameroid implantation, but recovered after 2 weeks in the PD-ECGF-treated group, and maintained a higher level of function during the examination period. Histological analysis demonstrated that angiogenesis and arteriogenesis occurred after PD-ECGF gene treatment. There was a decreased expression of the pro-apoptotic proteins, active caspase-3 and Bax, and the number of apoptotic myocardial cells was lower in the PD-ECGF-treated group. Histological examination demonstrated that no abnormal histological changes or neoplasms were found in any organs. We conclude that gene targeting of ischemic myocardium using PD-ECGF generated long-term improvement in cardiac function by causing angiogenesis, arteriogenesis and inhibiting apoptosis, but did not induce neoplasms in the remote organs, and may be a promising therapy.

Gene therapy for chronic myocardial ischemia using platelet-derived endothelial cell growth factor in dogs

Platelet-derived endothelial cell growth factor (PD-ECGF), also known as thymidine phosphorylase (TP), has been reported to possess angiogenic activity and to inhibit apoptosis. This study was performed to determine whether PD-ECGF/TP can be used to ameliorate chronic myocardial ischemia. Myocardial ischemia was created in 40 mongrel dogs by placement of an ameroid constrictor on the proximal left anterior descending coronary artery (LAD). Plasmid vector encoding human PD-ECGF/TP cDNA (pCIhTP group; n = 12), empty vector pCI (pCI group; n = 12), or saline (Saline group; n = 12) was directly injected into the LAD territory 3 wk after ameroid constrictor implantation. Myocardial blood flow was detected using PET at baseline, 3 wk after ameroid constrictor implantation, and 2 wk after therapeutic treatment. At the end of the experiment, the hearts were isolated for biological and histological analysis. In the pCIhTP group, the transfected heart strongly expressed PD-ECGF/TP. The size of the infarct was smaller in the pCIhTP group than in the pCI or Saline group. The number of apoptotic myocardial cells was decreased in the pCIhTP group compared with the control groups based on triple immunohistochemical staining for von Willebrand factor, alpha-actin smooth muscle cells, and single-strand DNA. The level of proapoptotic protein Bax markedly decreased in the pCIhTP group compared with the other groups. Double immunohistochemical staining for von Willebrand factor and alpha-actin smooth muscle cells demonstrated that angiogenesis and arteriogenesis occurred, and paralleled the changes in myocardial blood flow and myocardial function in the pCIhTP group. We conclude that genetic approaches using PD-ECGF/TP to target the myocardium are effective for alleviating chronic myocardial ischemia.

Fas-mediated apoptosis in adriamycin-induced cardiomyopathy in rats: In vivo study.

The precise molecular mechanism of Adriamycin-induced cardiomyopathy (ADR-CM) is still unknown. We address the demonstration of apoptotic myocardial cell death and the apoptosis-inducing molecules in ADR-CM induced in rats. Until 8 weeks after the first administration of ADR, there was no increase in the number of labeled cells by terminal deoxynucleotidyl transferase assay (TUNEL method). Apoptotic indices increased significantly at weeks 9 and 10 in hearts of the ADR-treated group but not in those of the control group (0.42+/-0.12% versus 0.10+/-0.02% and 0.86+/-0.11% versus 0.09+/-0.04% at weeks 9 and 10, respectively). DNA ladder formation was also observed in the myocardial tissues during the late stages of the ADR-CM of rats. There was no significant difference in expression of p53 gene between the ADR group and the control group at either the message or the protein level. An overexpression of Fas antigen was shown in myocardial cells of ADR-treated hearts at weeks 9 and 10 by both Western blotting and immunofluorescent staining. Furthermore, we confirmed that neutralization of anti-Fas ligand antibody inhibited ADR-induced apoptosis. Apoptotic cell death was observed in the hearts of ADR-CM rats, and the number of apoptotic myocardial cells increased with the deterioration of morphological findings and cardiac function, indicating that apoptosis may be an important mechanism of loss of myocardial cells and cardiac dysfunction in ADR-CM. Apoptosis in ADR-CM rats is not p53-dependent but rather is executed through a Fas-mediated pathway.