Efficacy and safety of stem cell therapy in patients with dilated cardiomyopathy: a systematic appraisal and meta-analysis.

BACKGROUND: The clinical significance of stem cell therapy in the treatment of dilated cardiomyopathy remains unclear. This systemic appraisal and meta-analysis aimed to assess the efficacy and safety of stem cell therapy in patients with dilated cardiomyopathy. After searching the PubMed, Embase, and Cochrane library databases until November 2017, we conducted a meta-analysis to evaluate the efficacy and safety of stem cell therapy in patients with dilated cardiomyopathy. METHODS: The weighted mean difference (WMD), standard mean difference (SMD), relative risk (RR), and 95% confidence interval (CI) were summarized in this meta-analysis. Both fixed effects and random effects models were used to combine the data. Sensitivity analyses were conducted to evaluate the impact of an individual dataset on the pooled results. RESULTS: A total of eight randomized controlled trials, which involved 531 participants, met the inclusion criteria in this systematic appraisal and meta-analysis. Our meta-analysis showed that stem cell therapy improves left ventricular ejection fraction (SMD = 1.09, 95% CI 0.29 to 1.90, I2 = 92%) and reduces left ventricular end-systolic volume (SMD = - 0.36, 95% CI - 0.61 to - 0.10, I2 = 20.5%) and left ventricular end-diastolic chamber size (SMD = - 0.48, 95% CI - 0.89 to - 0.07, I2 = 64.8%) in patients with dilated cardiomyopathy. However, stem cell therapy has no effect on mortality (RR = 0.72, 95% CI 0.50 to 1.02, I2 = 30.2%) and 6-min-walk test (WMD = 51.52, 95% CI - 24.52 to 127.55, I2 = 94.8%). CONCLUSIONS: This meta-analysis suggests that stem cell therapy improves left ventricular ejection fraction and reduces left ventricular end-systolic volume and left ventricular end-diastolic chamber size in patients with dilated cardiomyopathy. However, future well-designed large studies might be necessary to clarify the effect of stem cell therapy in patients with dilated cardiomyopathy.

Glutathione S-Transferase M1 and T1 polymorphisms and hypertension risk: an updated meta-analysis.

Recently, Glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1), and their interaction with hypertension risk have been focused on. However, the results of previous studies have been inconsistent. Hence, the present meta-analysis was performed to explore the association. Twenty-two case-control studies met the inclusion criteria for GSTM1 (including 3577 hypertension cases and 3784 controls), twenty-two for GSTT1 (including 3741 cases and 4444 controls), and nine for their combined effects (including 1073 cases and 781 controls). Pooled analyses on the association between GSTM1 present/null polymorphism and hypertension risk were observed to be insignificant in overall and subgroup analyses. The individual who carries the GSTT1 null-genotype had a statistically significant overall population (OR = 1.28, 95% CI: 1.03, 1.60), Indians (OR = 2.45, 95% CI: 1.08, 5.59), and hospital-based controls (OR = 1.53, 95% CI: 1.21, 1.94). For the GSTM1-GSTT1 interaction, we found that the GSTM1/GSTT1 double-null-genotype was significantly associated with hypertension risks (double-null vs. double-present: OR = 2.68, 95% CI: 1.06, 6.81). To summarize, this meta-analysis indicates that Indians with the GSTT1 null-genotype has a raised hypertension risks; the GSTM1 null/GSTT1 null-genotype is association with raised hypertension risks, while the GSTM1 null-genotype is not associated with hypertension risks. In addition, I2 > 75% cannot be eliminated for GSTM1 in Indians or Asians, hence, it will be very important to explore the GSTM1 null-genotype and hypertension susceptibility in Indians and Asians for a large new sample, on population-based control study.

Anti-inflammatory activities of hepatocyte growth factor in post-ischemic heart failure.

Hepatocyte growth factor (HGF) alleviates acute and chronic inflammation in experimental inflammatory bowel disease, glomerulonephritis, and airway inflammation. However, the anti-inflammatory effects of HGF on myocardial infarction are not defined. The current study assessed the anti-inflammatory effects of HGF in post-ischemic heart failure. The left anterior descending coronary artery was ligated in rats, and adenovirus containing human HGF (Ad-HGF) or control virus (Ad-GFP) was administered intramyocardially. The quantity of proinflammatory cytokines secreted by cardiomyocytes, such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1ß, was evaluated. Cardiac function and LV remodeling were assessed using echocardiography and collagen deposition, respectively. Left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF) four weeks after injection were significantly increased in Ad-HGF-treated animals compared to the Ad-GFP group. HGF gene therapy improved ventricular geometry with a significantly decreased left ventricular end-diastolic diameter (LVEDD) and markedly reduced myocardial collagen deposition. Treatment with Ad-HGF significantly decreased the mRNA levels of TNF-α, IL-6, and IL-1ß in the non-infarcted region four weeks after injection. Changes of the TNF-α, IL-6, and IL-1ß levels in the non-infarcted region positively correlated with the LVEDD 4 weeks after infarction. Treatment of acute myocardial infarction (AMI) with Ad-HGF in the early stage of MI reduced the pro-inflammatory cytokine levels and preserved cardiac function. These findings indicated that Ad-HGF gene therapy alleviated ventricular remodeling after infarction by reducing inflammation.

Correction: Transplantation of HGF gene-engineered skeletal myoblasts improve infarction recovery in a rat myocardial ischemia model.

[This corrects the article DOI: 10.1371/journal.pone.0175807.].

Transplantation of HGF gene-engineered skeletal myoblasts improve infarction recovery in a rat myocardial ischemia model.

BACKGROUND: Skeletal myoblast transplantation seems a promising approach for the repair of myocardial infarction (MI). However, the low engraftment efficacy and impaired angiogenic ability limit the clinical efficiency of the myoblasts. Gene engineering with angiogenic growth factors promotes angiogenesis and enhances engraftment of transplanted skeletal myoblasts, leading to improved infarction recovery in myocardial ischemia. The present study evaluated the therapeutic effects of hepatocyte growth factor (HGF) gene-engineered skeletal myoblasts on tissue regeneration and restoration of heart function in a rat MI model. METHODS AND RESULTS: The skeletal myoblasts were isolated, expanded, and transduced with adenovirus carrying the HGF gene (Ad-HGF). Male SD rats underwent ligation of the left anterior descending coronary artery. After 2 weeks, the surviving rats were randomized into four groups and treated with skeletal myoblasts by direct injection into the myocardium. The survival and engraftment of skeletal myoblasts were determined by real-time PCR and in situ hybridization. The cardiac function with hemodynamic index and left ventricular architecture were monitored; The adenovirus-mediated-HGF gene transfection increases the HGF expression and promotes the proliferation of skeletal myoblasts in vitro. Transplantation of HGF-engineered skeletal myoblasts results in reduced infarct size and collagen deposition, increased vessel density, and improved cardiac function in a rat MI model. HGF gene modification also increases the myocardial levels of HGF, VEGF, and Bcl-2 and enhances the survival and engraftment of skeletal myoblasts. CONCLUSIONS: HGF engineering improves the regenerative effect of skeletal myoblasts on MI by enhancing their survival and engraftment ability.

Recombinant proteins secreted from tissue-engineered bioartificial muscle improve cardiac dysfunction and suppress cardiomyocyte apoptosis in rats with heart failure.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Recombinant human growth hormone secreted from tissue-engineered bioartificial muscle improves left ventricular function in rat with acute myocardial infarction.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Effects of transplanted myoblasts transfected with human growth hormone gene on improvement of ventricular function of rats.

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Effects of recombinant retroviral vector mediated human insulin like growth factor-1 gene transfection on skeletal muscle growth in rat.

BACKGROUND: This study transferred a recombinant gene encoding human insulin like growth factor-1 (hIGF-1) into modified primary skeletal myoblasts with a retroviral vector (pLgXSN) and determined whether the hIGF-1 promoted growth of skeletal muscle in rat. METHODS: hIGF-1cDNA was amplified in vitro from normal human liver cells by using RT-PCR and cloned into plasmid vector pLgXSN. The recombinant vector pLghIGF-1SN and control vector pLgGFPSN were transfected into packaging cell PT67 and G418 was used to select positive colony. Myoblasts were infected with a high titre viral supernatant and transduction efficiency was evaluated as GFP expression. The expression of hIGF-1 mRNA in myoblasts was investigated by immunocytochemistry and RT-PCR. MTT assays detected the growth of myoblasts in vitro. Myoblasts transduced with pLghIGF-1SN were injected into hind limb muscles of 10 - 12 week male SD rats. Formed tissues were harvested 4 weeks later. Myocyte diameter, mean weight of hind limb and body were measured to evaluate the skeletal muscle growth. RESULTS: Recombinant retroviral plasmid vector pLghIGF-1SN was constructed successfully. The titre of the packaged recombinant retrovirus was 1 x 10(6) cfu/ml. The transfection rate of PT67 cells reached 100% after G418 screening. hIGF-1 expression was positive in myoblast-IGF-1. The proliferation rate of myoblast-IGF-1 in vitro was higher than GFP-myoblast or myoblast (P < 0.05). The mean weights of hind limb and body of rats injected myoblast-IGF-1 were higher than those of the rats injected with myoblast-GFP or myoblast (P < 0.05). Myocyte diameter had a significant increase in IGF-1 group compared to GFP group and myoblast group (P < 0.05). CONCLUSIONS: The transfection of the human IGF-1 gene mediated by a retroviral vector can promote the growth of skeletal muscle in rats. Genetically modified primary skeletal myoblasts provide a possibly effective approach to treat some skeletal muscle diseases.