1,721,017 research outputs found
Mesenchymal stem cell therapy for heart disease.
No full textMesenchymal stem cells (MSC) are adult stem cells with capacity for self-renewal and multi-lineage differentiation. Initially described in bone marrow, MSC are also present in other organs and tissues. From a therapeutic perspective, facilitated by the ease of preparation and immunologic privilege, MSC are emerging as an extremely promising therapeutic agent for tissue regeneration and repair. Studies in animal models of myocardial infarction have demonstrated the ability of transplanted MSC to engraft and differentiate into cardiomyocytes and vasculature cells. Most importantly, engrafted MSC secrete a wide array of soluble factors that mediate beneficial paracrine effects and greatly contribute to cardiac repair. Together, these properties can be harnessed to both prevent and reverse remodeling in the ischemically injured ventricle. In proof-of-concept and phase I clinical trials, MSC therapy improved left ventricular function, induced reverse remodeling, and decreased scar size. This chapter reviews the current understanding of MSC biology and mechanism of action in cardiac repair of MSC therapy for cardiac disease
Mesenchymal stem cell therapy for heart disease.
No full textMesenchymal stem cells (MSC) are adult stem cells with capacity for self-renewal and multi-lineage differentiation. Initially described in the bone marrow, MSC are also present in other organs and tissues. From a therapeutic perspective, because of their easy preparation and immunologic privilege, MSC are emerging as an extremely promising therapeutic agent for tissue regeneration and repair. Studies in animal models of myocardial infarction have demonstrated the ability of transplanted MSC to engraft and differentiate into cardiomyocytes and vascular cells. Most importantly, engrafted MSC secrete a wide array of soluble factors that mediate beneficial paracrine effects and may greatly contribute to cardiac repair. Together, these properties can be harnessed to both prevent and reverse remodeling in the ischemically injured ventricle. In proof-of-concept and phase I clinical trials, MSC therapy improved left ventricular function, induced reverse remodeling, and decreased scar size. In this review we will focus on the current understanding of MSC biology and MSC mechanism of action in cardiac repair
Enhancing the cardiomyogenic potential of human mesenchymal stem cells by modulation of miR expression.
No full textIntroduction: it has been shown that mesenchymal stem cells (MSC) can differentiate into cardiomyocytes (CMC) both in vitro and in vivo. However, the efficiency of cardiac differentiation is very limited. Recently, it has been suggested that miR1, 133 and 499 are involved in cardiac development and stem cell differentiation. The role of these miR in MSC differentiation is currently unknown. Accordingly, we tested if the overexpression of miR1, 133 and 499 may favour the differentiation of MSC into CMC.
Methods: miR1, 133, and 499 were transiently overexpressed, one by one or in different combinations, in human MSC. Cardiac differentiation was evaluated by measuring the expression of the cardiac specific markers GATA4, Nkx2.5, Tbx5, MEF2c, MLC2v, Cx43, cTnT and α-MHC. Western Blot and immunocytochemistry (ICC) for cTnT and Cx43 were also performed.
Results: miR499 alone increased the expression of the early cardiac genes GATA4, Tbx5, MLC2v. In particular, miR499 exerted more pronounced effects compared with miR1 and miR133. Concomitant overexpression of miR499 and miR133 further increased the expression of Tbx5 and MEF2c. Western Blot analysis showed that miR499 increased the expression of late cardiac genes when overexpressed alone or in combination with miR133. Finally, ICC staining confirmed that miR499 in association with miR133 increase Cx43 and cTnT protein expression. Finally, the expression of cardiac specific protein α-MHC was more pronounced in MSC overexpressing miR499 alone or in combination with miR133.
Conclusions: concomitant overexpression of miR499 and miR133 successfully commit AMSC into CMC. Our data suggests that miR modulation can represent a promising approach to improve the efficiency of cardioregnerative therapy with multipotent stem cells
Overexpression of growth factors to improve cardiac differentiation of human mesenchymal stem cells derived from the amniotic membrane
No full textL’esposizione a persolfato d’ammonio riduce il controllo non adrenergico, non colinergico inibitorio (NANC-i) nelle vie aeree di cavia
No full textTo evaluate the effect of repeated exposure to ammonium
persulphate (AP) on NANC inhibitory innervation of guinea-pig
airways, we exposed male guinea-pigs to AP, by aerosol inhalation
at a concentration of 1 mg/m3 for 30 minutes for 5 days for three weeks. Control animals inhaled saline aerosol. After the last exposure, the animals were killed and the isolated whole trachea was cannulated at each extremity and mounted in an organ bath. Intraluminal pressure variations were measured by means of a pressure transducer. The inhibitory NANC responses to electrical field stimulation (3 and 10 Hz) were evaluated in the presence of hyoscine, piperoxane and propranolol. To evaluate both the amplitude and the duration of the responses, the area under the curve (AUC) was measured as Pa · seconds. Statistical analysis, was performed by analysis of variance. In the exposed animals, the in vitro NANC relaxations at 3 and 10 Hz were significantly reduced (P < 0.01). In particular, the AUC was 45.9 ± 12.1%, as compared to control at 3 Hz and 52.7 ± 14.1% at 10 Hz. In conclusion, the impairment in NANC relaxation may represent one of the mechanisms subserving airway hyperreactivity induced by AP esposure
Exosomes from human cardiac progenitor cells, but not those from patient-matched bone marrow-derived mesenchymal stem cells,improve cardiac function after myocardial infarction in vivo
No full textBackground: Both human cardiac progenitor cells (CPC) and bone marrow-derived mesenchymal stem cells (MSC) have been tested in clinical trials of cell transplantation in patients with myocardial infarction (MI). We have recently shown that Exosomes (secreted nanovesicles; Exo) from CPC account for cardioprotective and proangiogenic activities of these cells both in vitro and in vivo. This study aimed to compare Exo-CPC and Exo-MSC in terms of cardioprotective effects and functional improvement after MI. The role of microRNA (miRNA) and ischemic preconditioning (IPC) were assessed.
Methods: CPC and MSC were derived from right atrial appendage and bone aspirate from patients undergoing heart valve surgery. Samples from both tissues were obtained for a patient-matched comparison of Exo from the two cell lines. Exo were isolated by differential ultracentrifugation of conditioned media from CPC or MSC. Anti-apoptotic and proangiogenic effects of Exo-CPC and Exo-MSC were assessed in vitro and compared with Exo from human dermal fibroblast cell line (Exo-F). IPC was performed by subjecting CPC or MSC to two short rounds of hypoxia and glucose deprivation. miRNA profiles of Exo were assessed by real-time PCR. Exo-CPC and Exo-MSC from 8 patients were injected intramyocardially in 8 rats each after permanent ligation of the left anterior descending coronary artery. Left ventricular ejection fraction (LVEF) was measured by echocardiography 1 and 4 weeks after MI.
Results: Although both Exo-CPC and Exo-MSC inhibited cardiomyocyte (CM) apoptosis after serum starvation in vitro if compared with Exo-F, Exo-CPC showed higher efficacy (21±4% Exo-CPC; 28±4% Exo-MSC; 40±5% Exo-F). IPC of Exo-producing cells further reduced numbers of apoptotic CM (17±1% Exo-CPC; 23±3% Exo-MSC). Exo-CPC, but not Exo-F, were proangiogenic in HUVEC cells. miR-210, miR132 and miR-146a were among the most highly enriched miRNA in Exo-CPC. CM transfected with miR-210 or miR-132 mimics showed increased tolerance to apoptosis, whereas siRNA specific for these miRNA had opposite effects. In vivo, LVEF was significantly improved in hearts injected with Exo-CPC compared to those injected with patient-matched Exo-MSC both at 1 week (87.0±9.9% vs 61.1±11.9; p<0.05) and 4 weeks after MI (75.4±8.9% vs 58.7±18.4%; p<0.05).
Conclusion: These results from patient-matched analyses show, for the first time, that Exo-CPC is superior to Exo-MSC at inhibiting CM apoptosis in vitro, and at improving cardiac function after MI in vivo. As a cell-free approach, Exo could streamline clinical translation of regenerative heart therapy
Exosomes from Human Cardiac Progenitor Cells Preserve Cardiac Function Long Term after Myocardial Infarction
No full textIntroduction: Recent evidence suggests cardiac progenitor cells (CPC) may improve cardiac function after injury. The
underlying mechanisms are indirect, but their mediators remain unidentified. Exosomes (Exo) act as paracrine signalling
mediators. Here we report that Exo secreted by human CPC are crucial cardioprotective agents that improve left
ventricular ejection fraction (LVEF %) in long term animal model of infarct.
Methods: Medium from CPC or normal human dermal fibroblasts (NHDF) was conditioned for 5-7 days and subjected to
differential centrifugation for Exo isolation. Exo from CPC (Exo-CPC) were tested in-vitro for their functional activity such
as anti-apoptotic and pro-angiogenic effects and compared with Exo from NHDF (Exo-F). The content of micro-RNA
(miRNA) has been analysed by real-time PCR in Exo-CPC vs Exo-F. Exo-CPC derived from six patients were pooled and
intramyocardially injected in-vivo in animal model of permanent left anterior descending (LAD) coronary ligation. One and
four weeks after injection LVEF was evaluated by echocardiography and hearts were processed for histological analysis.
Results: Exo-CPC inhibited apoptosis in cardiomyocytes, while enhancing tube formation in human endothelial cells invitro
compared to Exo-F. Exo-CPC were enriched in miR-210, miR-132, miR-146a, and miR-181a compared to Exo-F. In
gain-of-function studies, miR-210 and miR-146a inhibited apoptosis in cardiomyocytes by downregulating their targets
ephrinA3/PTP1b and Nox4 respectively. miR-132 downregulated its target RasGAP-p120 and enhanced angiogenesis.
Moreover, Exo-CPC, but not Exo-F, downregulated anti-apoptotic factors in cardiomyocytes. Infarcted hearts injected
with Exo-CPC significantly preserved the LVEF after one week (84.00±1.6%) and the effect was preserved after four
weeks (80.57±2.3%) compared with animals injected with Exo-F (60.71±7.4%; 48.00±4.6% one and four weeks
respectively). Moreover Exo-CPC injected hearts showed significantly reduced scar size (6.7±2.0% Exo-CPC vs
19.25±3.4% Exo-F).
Summary/Conclusion: Exo are the active component of the paracrine secretion of human CPC. They are enriched in
miRNA with cardioprotective and proangiogenic activities. Exo-CPC preserve heart function in a long term animal model
of permanent LAD ligation. As a cell-free approach, Exo could circumvent many of the limitations of cell transplantation
Concomitant overexpression of IGF1 and BMP2 in mesenchymal stem cells mediates cytoprotection through both autocrine and paracrine activation of Akt, Erk1/2 and SMAD1/5/8 pathways.
No full textBackground. Bone marrow mesenchymal stem cells (BM-MSC) are valuable tools for cardiac repair, acting mainly through release of paracrine factors. However, the effects of BM-MSC are limited by poor engraftment and low rate of differentiation events. To overcome these limitations, we genetically engineered BM-MSC with a novel bicistronic lentivirus co-expressing IGF1 and BMP2 (IB), two factors known to be involved in both cardiac differentiation and cytoprotection.
Methods. Rat BM-MSC were transduced with a control virus (GFP-MSC) or IB virus (IB-MSC). Autocrine and paracrine cytoprotection was evaluated in transduced MSC or in H9c2 cells treated with unconditioned (CTRL-M) or conditioned media (GFP-CM or IB-CM), after 24h of hypoxia. Cell viability was measured by MTS assay. Apoptosis was evaluated through caspase-3 activation. Transcriptional levels of pro and anti-apoptotic genes in H9c2 were measured by RT-PCR. Activation of IGF1 and BMP2 pro-survival pathways (Akt, ERK1/2, and SMAD1/5/8) in both MSC and H9c2 were assessed by western blot.
Results. IB-MSC showed a marked reduction of apoptosis (-50% p<0.001) vs GFP-MSC after 24h of hypoxia. IB-CM increased H9c2 viability (+32,1% p<0.001) compared with CTRL-M, while GFP-CM had no effect. Caspase-3 activation was reduced in the presence of IB-CM of 63,9% vs CTRL-M (p<0.001) and of 49,7 % vs GFP-MSC (p<0.05). H9c2 treated with IB-CM showed enhanced expression of Bcl-2 and Stat3 pro-survival genes, and inhibition of FasL and TNFalpha pro-apoptotic genes. Both IB-MSC or IB-CM treated-H9c2 showed a strong activation of Akt, ERK1/2 and SMAD1/5/8 pathways, confirming that IGF1 and BMP2 transgenes are acting both in autocrine and paracrine manner.
Conclusions. IGF1 and BMP2 transgene overexpression in MSC increases cell survival and cytoprotective paracrine properties. In particular, these effects are mediated by the activation of pathways known to be involved in cell survival
Identification of cardioprotective factors produced by fetal mesenchymal stem cells through a combined transcriptomic and proteomic approach.
No full textBackground: mesenchymal stem cells of fetal origin (F-MSC) can be isolated from the amniotic membrane of human placenta. We have data showing that F-MSC exert remarkable cardioprotective and proangiogenic effects through paracrine mechanisms. However, the complete nature and scope of the soluble mediators of cardioprotection have not been investigated yet.
Methods: F-MSC were isolated from human term placenta. Human dermal fibroblasts were used as control population. Total RNA and proteins were extracted from cultured F-MSC (N=10) and fibroblasts (n=10) after 48 hrs of serum deprivation. Genome-wide expression profiling was performed on RNA samples with Illumina platform. Proteins extracted from both cell populations were analyzed by liquid chromatography-Fourier transform mass spectrometry (LC-FTMS).
Results: whole-transcriptome gene expression analysis revealed that 647 genes are significantly over-expressed in F-MSC vs fibroblasts. Among these genes, 131 are up-regulated more than 2 fold in F-MSC. Computational analysis led to the identification of 32 genes encoding for secreted factors. Among them, the known cardioprotective factors Midkine (MDK) and SPARC are highly up-regulated in F-MSC vs fibroblasts. qPCR confirmed that MDK (+8 fold, p<0.01) and SPARC (+5.8, p<0.01) are up-regulated in F-MSC. Intriguingly, the role of the majority of the identified secreted factors in heart repair is still unknown. LC-FTMS proteomic analysis identified 266 proteins significantly up-regulated in F-MSC vs fibroblasts, including 22 secreted proteins. Some of these candidates may have a potential beneficial role in heart repair. In particular, Pentraxin-3 (PTX3) and Galectin-1 (GAL1) emerged as putative mediators of the cardioprotective effects exerted by F-MSC.
Conclusion: using a combined transcriptomic and proteomic approach we identified known and novel putative cardioprotective factors produced by F-MSC. In particular, MDK, SPARC, PTX3 and GAL1 seem strong candidates. Further studies will help to fully dissect their role in myocardial repair
Novel IRES-based lentivirus co-expressing IGF1 and BMP2 enhances both cardiomyogenesis and cytoprotection of bone marrow-derived mesenchymal stem cells
No full text- …
