The Value of Index of Microvascular Resistance Measured Before and Following Percutaneous Coronary Intervention in Predicting Perioperative Myocardial Infarction in Patients With Stable Coronary Artery Disease / 中国循环杂志

Objectives: This study was designed to assess whether measurement of the index of microvascular resistance (IMR) before and following percutaneous coronary intervention (PCI) could help identify patients who develop periprocedural myocardial infarction (PPMI). Methods: 54 patients with stable coronary artery disease undergoing elective PCI were divided into PPMI group and no-PPMI group. IMR and FFR was measured before and following percutaneous coronary intervention (PCI) with a pressure wire. Times of balloon inflation was also analyzed. hs-TnI at 24 h post PCI was measured. rPIMR value was calculated. Results: IMR obtained at pre-PCI and post-PCI as well as rPIMR were significantly higher in PPMI patients than in no-PPMI patients (22.02±2.92 vs 17.46±3.44, 25.86±3.04 vs 18.96±2.84, 1.22±0.21 vs 0.94±0.24, all P<0.05, respectively). Patients with PPMI more frequently underwent pre- and post-dilatation(70.8% vs 36.7%, 54.2% vs 23.3%, P<0.05), respectively, the number of balloon inflations was significantly higher in patients with PPMI than in no-PPMI patients (4.33±1.79 vs 3.20±1.63, P<0.05). The area under the ROC curve for predicting PPMI event by pre-PCI IMR was 0.941 (95%CI: 0.884-0.998, P<0.05), cut-off value was 19.91 (sensitivity: 95.8% and specificity: 77.0%). Multivariate logistic analysis showed that pre- and post-PCI IMR, rPIMR were positively correlated with PPMI (all P<0.05). Conclusions: Measuring IMR and rPIMR may allow prospective identification of patients at increased risk of PPMI.

Hepatocyte growth factor gene-modified bone marrow-derived mesenchymal stem cells transplantation promotes angiogenesis in a rat model of hindlimb ischemia / 华中科技大学学报（医学）（英德文版）

Angiogenic gene therapy and cell-based therapy for peripheral arterial disease(PAD) have been studied intensively currently. This study aimed to investigate whether combining mesenchymal stem cells(MSCs) transplantation with ex vivo human hepatocyte growth factor(HGF) gene transfer was more therapeutically efficient than the MSCs therapy alone in a rat model of hindlimb ischemia. One week after establishing hindlimb ischemia models, Sprague-Dawley(SD) rats were randomized to receive HGF gene-modified MSCs transplantation(HGF-MSC group), untreated MSCs transplantation (MSC group), or PBS injection(PBS group), respectively. Three weeks after injection, angiogenesis was significantly induced by both MSCs and HGF-MSCs transplantation, and capillary density was the highest in the HGF-MSC group. The number of transplanted cell-derived endothelial cells was greater in HGF-MSC group than in MSC group after one week treatment. The expression of angiogenic cytokines such as HGF and VEGF in local ischemic muscles was more abundant in HGF-MSC group than in the other two groups. In vitro, the conditioned media obtained from HGF-MSCs cultures exerted proproliferative and promigratory effects on endothelial cells. It is concluded that HGF gene-modified MSCs transplantation therapy may induce more potent angiogenesis than the MSCs therapy alone. Engraftment of MSCs combined with angiogenic gene delivery may be a promising therapeutic strategy for the treatment of severe PAD.

Hepatocyte growth factor gene-modified bone marrow-derived mesenchymal stem cells transplantation promotes angiogenesis in a rat model of hindlimb ischemia / 华中科技大学学报（医学）（英德文版）

Angiogenic gene therapy and cell-based therapy for peripheral arterial disease(PAD) have been studied intensively currently. This study aimed to investigate whether combining mesenchymal stem cells(MSCs) transplantation with ex vivo human hepatocyte growth factor(HGF) gene transfer was more therapeutically efficient than the MSCs therapy alone in a rat model of hindlimb ischemia. One week after establishing hindlimb ischemia models, Sprague-Dawley(SD) rats were randomized to receive HGF gene-modified MSCs transplantation(HGF-MSC group), untreated MSCs transplantation (MSC group), or PBS injection(PBS group), respectively. Three weeks after injection, angiogenesis was significantly induced by both MSCs and HGF-MSCs transplantation, and capillary density was the highest in the HGF-MSC group. The number of transplanted cell-derived endothelial cells was greater in HGF-MSC group than in MSC group after one week treatment. The expression of angiogenic cytokines such as HGF and VEGF in local ischemic muscles was more abundant in HGF-MSC group than in the other two groups. In vitro, the conditioned media obtained from HGF-MSCs cultures exerted proproliferative and promigratory effects on endothelial cells. It is concluded that HGF gene-modified MSCs transplantation therapy may induce more potent angiogenesis than the MSCs therapy alone. Engraftment of MSCs combined with angiogenic gene delivery may be a promising therapeutic strategy for the treatment of severe PAD.

Recombinant proteins secreted from tissue-engineered bioartificial muscle improve cardiac dysfunction and suppress cardiomyocyte apoptosis in rats with heart failure / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Tissue-engineered bioartificial muscle-based gene therapy represents a promising approach for the treatment of heart diseases. Experimental and clinical studies suggest that systemic administration of insulin-like growth factor-1 (IGF-1) protein or overexpression of IGF-1 in the heart exerts a favorable effect on cardiovascular function. This study aimed to investigate a chronic stage after myocardial infarction (MI) and the potential therapeutic effects of delivering a human IGF-1 gene by tissue-engineered bioartificial muscles (BAMs) following coronary artery ligation in Sprague-Dawley rats.</p><p><b>METHODS</b>Ligation of the left coronary artery or sham operation was performed. Primary skeletal myoblasts were retrovirally transduced to synthesize and secrete recombinant human insulin-like growth factor-1 (rhIGF-1), and green fluorescent protein (GFP), and tissue-engineered into implantable BAMs. The rats that underwent ligation were randomly assigned to 2 groups: MI-IGF group (n = 6) and MI-GFP group (n = 6). The MI-IGF group received rhIGF-secreting BAM (IGF-BAMs) transplantation, and the MI-GFP group received GFP-secreting BAM (GFP-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: S-IGF group (n = 6) and S-GFP group (n = 6). The S-IGF group underwent IGF-1-BAM transplantation, and S-GFP group underwent GFP-BAM transplantation. IGF-1-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats after two weeks of operation was performed. Four weeks after the treatment, hemodynamics was performed. IGF-1 was measured by radioimmunoassay, and then the rats were sacrificed and ventricular samples were subjected to immunohistochemistry. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of bax and Bcl-2. TNF-α and caspase 3 expression in myocardium was examined by Western blotting.</p><p><b>RESULTS</b>Primary rat myoblasts were retrovirally transduced to secrete rhIGF-1 and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted consistent levels of hIGF (0.4 - 1.2 µg×BAM(-1)×d(-1)). When implanted into syngeneic rat, IGF-BAMs secreted and delivered rhIGF. Four weeks after therapy, the hemodynamics was improved significantly in MI rats treated with IGF-BAMs compared with those treated with GFP-BAMs. The levels of serum IGF-1 were increased significantly in both MI and sham rats treated with IGF-BAM. The mRNA expression of bax was lower and Bcl-2 expression was higher in MI-IGF group than MI-GFP group (P < 0.05). Western blotting assay showed TNF-α and caspase 3 expression was lower in MI-IGF group than MI-GFP group after therapy.</p><p><b>CONCLUSIONS</b>rhIGF-1 significantly improves left ventricular function and suppresses cardiomyocyte apoptosis in rats with chronic heart failure. Genetically modified tissue-engineered BAMs provide a method delivering recombinant protein for the treatment of heart failure.</p>

Recombinant human growth hormone secreted from tissue-engineered bioartificial muscle improves left ventricular function in rat with acute myocardial infarction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Experimental studies and preliminary clinical studies have suggested that growth hormone (GH) treatment may improve cardiovascular parameters in chronic heart failure (CHF). Recombinant human GH (rhGH) has been delivered by a recombinant protein, by plasmid DNA, and by genetically engineered cells with different pharmacokinetic and physiological properties. The present study aimed to examine a new method for delivery of rhGH using genetically modified bioartificial muscles (BAMs), and investigate whether the rhGH delivered by this technique improves left ventricular (LV) function in rats with CHF.</p><p><b>METHODS</b>Primary skeletal myoblasts were isolated from several Sprague-Dawley (SD) rats, cultured, purified, and retrovirally transduced to synthesize and secrete human rhGH, and tissue-engineered into implantable BAMs. Ligation of the left coronary artery or sham operation was performed. The rats that underwent ligation were randomly assigned to 2 groups: CHF control group (n = 6) and CHF treatment group (n = 6). The CHF control group received non-rhGH-secreting BAM (GFP-BAMs) transplantation, and the CHF treatment group received rhGH-secreting BAM (GH-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: sham control group (n = 6) and sham treatment group (n = 6). The sham control group underwent GFP-BAM transplantation, and the sham treatment group underwent GH-BAM transplantation. GH-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats with ligation of the left coronary artery or sham operation was performed. Eight weeks after the treatment, echocardiography was performed. hGH, insulin-like growth factor-1 (IGF-1) and TNF-alpha levels in rat serum were measured by radioimmunoassay and ELISA, and then the rats were killed and ventricular samples were subjected to immunohistochemistry.</p><p><b>RESULTS</b>Primary rat myoblasts were retrovirally transduced to secrete rhGH and tissue-engineered into implantable BAMs containing parallel arrays of postmitotic myofibers. In vitro, they secreted 1 to 2 microg of bioactive rhGH per day. When implanted into syngeneic rat, GH-BAMs secreted and delivered rhGH. Eight weeks after therapy, LV ejection fraction (EF) and fractional shortening (FS) were significantly higher in CHF rats treated with GH-BAMs than in those treated with GFP-BAMs ((65.0 +/- 6.5)% vs (48.1 +/- 6.8)%, P < 0.05), ((41.3 +/- 7.4)% vs (26.5 +/- 7.1)%, P < 0.05). LV end-diastolic dimension (LVEDD) was significantly lower in CHF rats treated with GH-BAM than in CHF rats treated with GFP-BAM (P < 0.05). The levels of serum GH and IGF-1 were increased significantly in both CHF and sham rats treated with GH-BAM. The level of serum TNF-alpha decreased more significantly in the CHF treatment group than in the CHF control group.</p><p><b>CONCLUSIONS</b>rhGH significantly improves LV function and prevents cardiac remodeling in rats with CHF. Genetically modified tissue-engineered bioartificial muscle provides a method delivering recombinant protein for the treatment of heart failure.</p>

Effects of transplanted myoblasts transfected with human growth hormone gene on improvement of ventricular function of rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Cell transplantation for myocardial repair is limited by early cell death. Gene therapy with human growth hormone (hGH) has been shown to promote angiogenesis and attenuate apoptosis in the experimental animal. This study was conducted to explore the effects of myoblast-based hGH gene therapy on heart function restoration and angiogenesis after myocardial infarction, and to compare the differences between myoblast-based hGH gene therapy and myoblast therapy.</p><p><b>METHODS</b>Myoblasts were isolated from several SD rats, cultured, purified, and transfected with plasmid pLghGHSN and pLgGFPSN. Radioimmunoassay (RIA) was used to detect the expression of hGH in these myoblasts. SD rats underwent the ligation of the left anterior descending coronary artery so as to establish a heart ischemia model. Thirty surviving rats that underwent ligation were randomly divided into 3 equal groups 2 weeks after left coronary artery occlusion: pLghGHSN group received myoblast infected with hGH gene transplantation; pLgGFPSN group received myoblast infected with GFP gene transplantation; control group: received cultured medium only. Four weeks after the injection the surviving rat underwent evaluation of cardiac function by echocardiography. The rats were killed and ventricular samples were undergone immunohistochemistry with hematoxylin-eosin and factor VIII. Cryosection was analyzed by fluorescence microscopy to examine the expression of green fluorescent protein. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to examine the mRNA expression of vascular endothelial growth factor (VEGF), bax and Bcl-2. hGH expression in myocardium was examined by Western blot.</p><p><b>RESULTS</b>Myoblast can be successfully isolated, cultured and transfected. The expression of hGH in transfected myoblast was demonstrated with RIA. Four weeks after therapy, the cardiac function was improved significantly in pLghGHSN group and pLgGFPSN group. Fractional shortening (FS) and ejection fraction (EF) in pLghGHSN group were elevated significantly compared with pLgGFPSN group and control group after therapy (FS: 36.9+/-5.3 vs 29.5+/-3.5, 21.8+/-2.9; EF: 56.9+/-4.3 vs 47.1+/-3.6, 38.4+/-4.8, P<0.05). Left ventricular end-diastolic dimension (LVEDD) and heart infracted size in pLghGHSN group were decreased significantly compared with pLgGFPSN group and control group after therapy (LVEDD: 5.9+/-0.3 vs 6.8+/-0.2, 8.6+/-0.3; heart infracted size: (34.5+/-4.2)% vs (40.0+/-3.9)%, (46.1+/-3.8)%, P<0.05); Green fluorescence was detected in cryosection of pLgGFPSN group. The capillary density of the pLgGFPSN group was significantly greater than those of the pLghGHSN group and control group (P<0.05). The mRNA expression of VEGF and Bcl-2/bax in pLghGHSN group was higher than in pLgGFPSN group or control group (P<0.05). The expression of hGH gene in myocardium tissue can be detected by Western blot assay in pLghGHSN group.</p><p><b>CONCLUSIONS</b>Transplantation of heart cells transfected with hGH induced greater angiogenesis and effect of antiapoptosis than transplantation of cells transfected with GFP. Combined GH gene transfer and cell transplantation provided an effective strategy for improving postinfarction ventricular function.</p>