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1.
Polymers (Basel) ; 14(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35335506

RESUMEN

Four 1,4-bis((9H-carbazol-9-yl)methyl)benzene-containing polymers (PbCmB, P(bCmB-co-bTP), P(bCmB-co-dbBT), and P(bCmB-co-TF)) were electrosynthesized onto ITO transparent conductive glass and their spectral and electrochromic switching performances were characterized. The PbCmB film displayed four types of color variations (bright gray, dark gray, dark khaki, and dark olive green) from 0.0 to 1.2 V. P(bCmB-co-bTP) displayed a high transmittance variation (∆T = 39.56% at 685 nm) and a satisfactory coloration efficiency (η = 160.5 cm2∙C-1 at 685 nm). Dual-layer organic electrochromic devices (ECDs) were built using four bCmB-containing polycarbazoles and poly(3,4-ethylenedioxythiophene) (PEDOT) as anodes and a cathode, respectively. PbCmB/PEDOT ECD displayed gainsboro, dark gray, and bright slate gray colors at -0.4 V, 1.0 V, and 2.0 V, respectively. The P(bCmB-co-bTP)/PEDOT ECD showed a high ∆T (40.7% at 635 nm) and a high coloration efficiency (η = 428.4 cm2∙C-1 at 635 nm). The polycarbazole/PEDOT ECDs exhibited moderate open circuit memories and electrochemical redox stability. The characterized electrochromic properties depicted that the as-prepared polycarbazoles had a satisfactory application prospect as an electrode for the ECDs.

2.
Bioanalysis ; 13(21): 1597-1616, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34708658

RESUMEN

Flow cytometry is a powerful technology used in research, drug development and clinical sample analysis for cell identification and characterization, allowing for the simultaneous interrogation of multiple targets on various cell subsets from limited samples. Recent advancements in instrumentation and fluorochrome availability have resulted in significant increases in the complexity and dimensionality of flow cytometry panels. Though this increase in panel size allows for detection of a broader range of markers and sub-populations, even in restricted biological samples, it also comes with many challenges in panel design, optimization, and downstream data analysis and interpretation. In the current paper we describe the practices we established for development of high-dimensional panels on the Aurora spectral flow cytometer to aid clinical sample analysis.


Asunto(s)
Citometría de Flujo , Ensayos Clínicos como Asunto , Humanos
3.
ACS Nano ; 13(11): 12525-12539, 2019 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-31621284

RESUMEN

Myocardial microenvironment plays a decisive role in guiding the function and fate of cardiomyocytes, and engineering this extracellular niche holds great promise for cardiac tissue regeneration. Platforms utilizing hybrid hydrogels containing various types of conductive nanoparticles have been a critical tool for constructing engineered cardiac tissues with outstanding mechanical integrity and improved electrophysiological properties. However, there has been no attempt to directly compare the efficacy of these hybrid hydrogels and decipher the mechanisms behind how these platforms differentially regulate cardiomyocyte behavior. Here, we employed gelatin methacryloyl (GelMA) hydrogels containing three different types of carbon-based nanoparticles: carbon nanotubes (CNTs), graphene oxide (GO), and reduced GO (rGO), to investigate the influence of these hybrid scaffolds on the structural organization and functionality of cardiomyocytes. Using immunofluorescent staining for assessing cellular organization and proliferation, we showed that electrically conductive scaffolds (CNT- and rGO-GelMA compared to relatively nonconductive GO-GelMA) played a significant role in promoting desirable morphology of cardiomyocytes and elevated the expression of functional cardiac markers, while maintaining their viability. Electrophysiological analysis revealed that these engineered cardiac tissues showed distinct cardiomyocyte phenotypes and different levels of maturity based on the substrate (CNT-GelMA: ventricular-like, GO-GelMA: atrial-like, and rGO-GelMA: ventricular/atrial mixed phenotypes). Through analysis of gene-expression patterns, we uncovered that the engineered cardiac tissues matured on CNT-GelMA and native cardiac tissues showed comparable expression levels of maturation markers. Furthermore, we demonstrated that engineered cardiac tissues matured on CNT-GelMA have increased functionality through integrin-mediated mechanotransduction (via YAP/TAZ) in contrast to cardiomyocytes cultured on rGO-GelMA.


Asunto(s)
Miocardio , Nanotubos de Carbono/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Células Cultivadas , Grafito/química , Hidrogeles/química , Mecanotransducción Celular/fisiología , Miocardio/citología , Miocardio/metabolismo , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/fisiología , Ratas , Ratas Sprague-Dawley
4.
PLoS One ; 14(2): e0211909, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30811450

RESUMEN

Transcriptomic analysis of pulmonary microvascular endothelial cells from experimental models offers insight into pulmonary arterial hypertension (PAH) pathobiology. However, culturing may alter the molecular profile of endothelial cells prior to analysis, limiting the translational relevance of results. Here we present a novel and validated method for isolating RNA from pulmonary microvascular endothelial cells (PMVECs) ex vivo that does not require cell culturing. Initially, presumed rat PMVECs were isolated from rat peripheral lung tissue using tissue dissociation and enzymatic digestion, and cells were cultured until confluence to assess endothelial marker expression. Anti-CD31, anti-von Willebrand Factor, and anti-α-smooth muscle actin immunocytochemistry/immunofluorescence signal was detected in presumed rat PMVECs, but also in non-endothelial cell type controls. By contrast, flow cytometry using an anti-CD31 antibody and isolectin 1-B4 (from Griffonia simplicifolia) was highly specific for rat PMVECs. We next developed a strategy in which the addition of an immunomagnetic selection step for CD31+ cells permitted culture-free isolation of rat PMVECs ex vivo for RNA isolation and transcriptomic analysis using fluorescence-activated cell sorting. Heterogeneity in the validity and reproducibility of results using commercial antibodies against endothelial surface markers corresponded to a substantial burden on laboratory time, labor, and scientific budget. We demonstrate a novel protocol for the culture-free isolation and transcriptomic analysis of rat PMVECs with translational relevance to PAH. In doing so, we highlight wide variability in the quality of commonly used biological reagents, which emphasizes the importance of investigator-initiated validation of commercial biomaterials.


Asunto(s)
Materiales Biocompatibles/farmacología , Separación Celular , Células Endoteliales/metabolismo , Hipertensión Pulmonar/metabolismo , Pulmón/metabolismo , Microvasos/metabolismo , Animales , Antígenos de Diferenciación/biosíntesis , Células Endoteliales/patología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hipertensión Pulmonar/patología , Pulmón/irrigación sanguínea , Pulmón/patología , Microvasos/patología , Ratas
5.
Adv Healthc Mater ; 8(3): e1801146, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30609312

RESUMEN

Cardiac tissue is characterized by being dynamic and contractile, imparting the important role of biomechanical cues in the regulation of normal physiological activity or pathological remodeling. However, the dynamic mechanical tension ability also varies due to extracellular matrix remodeling in fibrosis, accompanied with the phenotypic transition from cardiac fibroblasts (CFs) to myofibroblasts. It is hypothesized that the dynamic mechanical tension ability regulates cardiac phenotypic transition within fibrosis in a strain-mediated manner. In this study, a microdevice that is able to simultaneously and accurately mimic the biomechanical properties of the cardiac physiological and pathological microenvironment is developed. The microdevice can apply cyclic compressions with gradient magnitudes (5-20%) and tunable frequency onto gelatin methacryloyl (GelMA) hydrogels laden with CFs, and also enables the integration of cytokines. The strain-response correlations between mechanical compression and CFs spreading, and proliferation and fibrotic phenotype remolding, are investigated. Results reveal that mechanical compression plays a crucial role in the CFs phenotypic transition, depending on the strain of mechanical load and myofibroblast maturity of CFs encapsulated in GelMA hydrogels. The results provide evidence regarding the strain-response correlation of mechanical stimulation in CFs phenotypic remodeling, which can be used to develop new preventive or therapeutic strategies for cardiac fibrosis.


Asunto(s)
Matriz Extracelular , Hidrogeles/química , Dispositivos Laboratorio en un Chip , Miocardio , Miofibroblastos , Estrés Mecánico , Animales , Citocinas/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Fibrosis , Miocardio/metabolismo , Miocardio/patología , Miofibroblastos/metabolismo , Miofibroblastos/patología , Ratas , Ratas Sprague-Dawley
6.
Lab Chip ; 17(10): 1732-1739, 2017 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-28448074

RESUMEN

Prevailing commercialized cardiac platforms for in vitro drug development utilize planar microelectrode arrays to map action potentials, or impedance sensing to record contraction in real time, but cannot record both functions on the same chip with high spatial resolution. Here we report a novel cardiac platform that can record cardiac tissue adhesion, electrophysiology, and contractility on the same chip. The platform integrates two independent yet interpenetrating sensor arrays: a microelectrode array for field potential readouts and an interdigitated electrode array for impedance readouts. Together, these arrays provide real-time, non-invasive data acquisition of both cardiac electrophysiology and contractility under physiological conditions and under drug stimuli. Human induced pluripotent stem cell-derived cardiomyocytes were cultured as a model system, and used to validate the platform with an excitation-contraction decoupling chemical. Preliminary data using the platform to investigate the effect of the drug norepinephrine are combined with computational efforts. This platform provides a quantitative and predictive assay system that can potentially be used for comprehensive assessment of cardiac toxicity earlier in the drug discovery process.


Asunto(s)
Electrofisiología Cardíaca/instrumentación , Técnicas de Cultivo de Célula/instrumentación , Dispositivos Laboratorio en un Chip , Modelos Cardiovasculares , Potenciales de Acción/fisiología , Electrofisiología Cardíaca/métodos , Células Cultivadas , Humanos , Células Madre Pluripotentes Inducidas/citología , Microelectrodos , Miocitos Cardíacos/citología , Miocitos Cardíacos/fisiología
7.
Adv Funct Mater ; 27(12)2017 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-30319321

RESUMEN

Bioprinting is the most convenient microfabrication method to create biomimetic three-dimensional (3D) cardiac tissue constructs, which can be used to regenerate damaged tissue and provide platforms for drug screening. However, existing bioinks, which are usually composed of polymeric biomaterials, are poorly conductive and delay efficient electrical coupling between adjacent cardiac cells. To solve this problem, we developed a gold nanorod (GNR) incorporated gelatin methacryloyl (GelMA)-based bioink for printing 3D functional cardiac tissue constructs. The GNR concentration was adjusted to create a proper microenvironment for the spreading and organization of cardiac cells. At optimized concentration of GNR, the nanocomposite bioink had a low viscosity, similar to pristine inks, which allowed for the easy integration of cells at high densities. As a result, rapid deposition of cell-laden fibers at a high resolution was possible, while reducing shear stress on the encapsulated cells. In the printed GNR constructs, cardiac cells showed improved cell adhesion and organization when compared to the constructs without GNRs. Furthermore, the incorporated GNRs bridged the electrically resistant pore walls of polymers, improved the cell-to-cell coupling, and promoted synchronized contraction of the bioprinted constructs. Given its advantageous properties, this gold nanocomposite bioink may find wide application in cardiac tissue engineering.

8.
Food Chem ; 200: 32-7, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26830557

RESUMEN

Magnetic molecularly imprinted polymers (MMIPs) were synthesized through precipitation polymerization using malachite green (MG) as template, methacrylic acid as monomer, ethylene dimethacrylate as crosslinker, and Fe3O4 magnetite as magnetic component. MMIPs were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, and vibrating sample magnetometry. Under the optimum condition, the MMIPs obtained exhibited quick binding kinetics and high affinity to MG in the solution. Scatchard plot analysis revealed that the MMIPs contained only one type of binding site with dissociation constant of 24.0 µg mL(-1). The selectivity experiment confirmed that the MMIPs exhibited higher selective binding capacity for MG than its structurally related compound (e.g., crystal violet). As a sorbent for the extraction of MG in sample preparation, MMIPs together with the absorbed analytes could easily be separated from the sample matrix with an external magnet. After elution with methanol/acetic acid (9:1, v/v), MG in the eluent was determined by high-performance liquid chromatography coupled with UV detector with recoveries of 94.0-115%. Results indicated that the as-prepared MMIPs are promising materials for MG analysis in aquatic products.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Impresión Molecular/métodos , Polímeros/química , Colorantes de Rosanilina/química
9.
Circ Res ; 117(5): 450-9, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26082557

RESUMEN

RATIONALE: In response to injury, the rodent heart is capable of virtually full regeneration via cardiomyocyte proliferation early in life. This regenerative capacity, however, is diminished as early as 1 week postnatal and remains lost in adulthood. The mechanisms that dictate postinjury cardiomyocyte proliferation early in life remain unclear. OBJECTIVE: To delineate the role of miR-34a, a regulator of age-associated physiology, in regulating cardiac regeneration secondary to myocardial infarction (MI) in neonatal and adult mouse hearts. METHODS AND RESULTS: Cardiac injury was induced in neonatal and adult hearts through experimental MI via coronary ligation. Adult hearts demonstrated overt cardiac structural and functional remodeling, whereas neonatal hearts maintained full regenerative capacity and cardiomyocyte proliferation and recovered to normal levels within 1-week time. As early as 1 week postnatal, miR-34a expression was found to have increased and was maintained at high levels throughout the lifespan. Intriguingly, 7 days after MI, miR-34a levels further increased in the adult but not neonatal hearts. Delivery of a miR-34a mimic to neonatal hearts prohibited both cardiomyocyte proliferation and subsequent cardiac recovery post MI. Conversely, locked nucleic acid-based anti-miR-34a treatment diminished post-MI miR-34a upregulation in adult hearts and significantly improved post-MI remodeling. In isolated cardiomyocytes, we found that miR-34a directly regulated cell cycle activity and death via modulation of its targets, including Bcl2, Cyclin D1, and Sirt1. CONCLUSIONS: miR-34a is a critical regulator of cardiac repair and regeneration post MI in neonatal hearts. Modulation of miR-34a may be harnessed for cardiac repair in adult myocardium.


Asunto(s)
Corazón/fisiología , MicroARNs/fisiología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Regeneración/fisiología , Animales , Animales Recién Nacidos , Femenino , Masculino , Ratones , Miocitos Cardíacos/patología , Miocitos Cardíacos/fisiología , Embarazo
10.
PLoS One ; 10(3): e0115430, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25757076

RESUMEN

BACKGROUND: We previously showed that injection of peptide nanofibers (NF) combined with autologous bone marrow mononuclear cells (MNC) immediately after coronary artery ligation improves cardiac performance in pigs. To evaluate the clinical feasibility, this study was performed to determine the therapeutic time window for NF/MNC therapy in acute myocardial infarction (MI). METHODS AND RESULTS: A total of 45 adult minipigs were randomly grouped into 7 groups: sham or MI plus treatment with NS (normal saline), or NF or MNC alone at 1 day (1D) post-MI, or NF/MNC at 1, 4, or 7 days post-MI (N≥6). Cardiac function was assessed by echocardiography and ventricular catheterization. Compared with the NS control, pigs treated with NF/MNC at 1 day post-MI (NF/MC-1D) had the greatest improvement in left ventricle ejection fraction (LVEF; 55.1±1.6%; P<0.01 vs. NS) 2 months after MI. In contrast, pigs treated with either NF/MNC-4D or NF/MNC-7D showed 48.9±0.8% (P<0.05 vs. NS) and 43.5±2.3% (n.s. vs. NS) improvements, respectively. The +dP/dt and -dP/dt, infarct size and interstitial collagen content were also improved in the NF/MNC-1D and -4D groups but not in the -7D group. Mechanistically, MNC quality and the states of systemic inflammation and damaged heart tissue influence the therapeutic efficiency of NF/MNC therapy, as revealed by another independent study using 16 pigs. CONCLUSIONS: Injection of NF/MNC at 1 or 4 days, but not at 7 days post-MI, improves cardiac performance and prevents ventricular remodeling, confirming the importance of early intervention when using this therapy for acute MI.


Asunto(s)
Infarto del Miocardio/terapia , Nanofibras/uso terapéutico , Animales , Trasplante de Médula Ósea , Diferenciación Celular , Esquema de Medicación , Células Endoteliales/fisiología , Endotelio Vascular/patología , Infarto del Miocardio/patología , Miocardio/patología , Péptidos/uso terapéutico , Porcinos , Porcinos Enanos , Factores de Tiempo , Trasplante Autólogo , Remodelación Ventricular
11.
Tissue Eng Part A ; 21(9-10): 1662-71, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25686878

RESUMEN

Accumulating evidence suggests that the benefits of cell therapy for cardiac repair are modest and transient due to progressive harmful cardiac remodeling as well as loss of transplanted cells. We previously demonstrated that injection of peptide nanofibers (NFs) reduces ventricular remodeling and facilitates cell retention at 1 month after acute myocardial infarction (MI) in pigs. However, it remains unclear whether these benefits still persist as the material is being degraded. In this study, 2 mL of placebo or NFs, with or without 1×10(8) mononuclear cells (MNCs), was injected into the pig myocardium after MI (n≥5 in each group), and cardiac function was assessed by echocardiography, including myocardial deformation analyses and catheterization at 3 months post-MI. Our results reveal that MNC-only injection slightly improved cardiac systolic function at 1 month post-MI, but this benefit was lost at later time points (ejection fraction: 42.0±2.3 in MI+normal saline [NS] and 43.5±1.1 in MI+MNCs). In contrast, NF-only injection resulted in improved cardiac diastolic function and reduced pathological remodeling at 3 months post-MI. Furthermore, combined injection of MNCs/NFs provided a greater and longer term cardiac performance (52.1±1.2 in MI+MNCs/NFs, p<0.001 versus MI+NS and MI+MNCs) and 11.3-fold transplanted cell retention. We also found that about 30% NFs remained at 3 months after injection; however, endogenous myofibroblasts were recruited to the NF-injected microenvironment to replace the degraded NFs and preserved cardiac dimensions and mechanics. In conclusion, we demonstrated that injection of NFs contributes to preservation of ventricular mechanical integrity and sustains MNC efficacy at 3 months postinjection.


Asunto(s)
Células de la Médula Ósea/citología , Trasplante de Médula Ósea , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Péptidos/farmacología , Polietilenglicoles/farmacología , Polietileneimina/farmacología , Animales , Capilares/efectos de los fármacos , Capilares/patología , Microambiente Celular/efectos de los fármacos , Diástole/efectos de los fármacos , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Fibrosis , Hemodinámica/efectos de los fármacos , Inyecciones , Miofibroblastos/citología , Miofibroblastos/efectos de los fármacos , Nanofibras/química , Nanogeles , Sus scrofa , Sístole/efectos de los fármacos , Resultado del Tratamiento
12.
Biomater Sci ; 2(4): 567-80, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26827729

RESUMEN

The heart is an extremely sophisticated organ with nanoscale anisotropic structure, contractility and electro-conductivity; however, few studies have addressed the influence of cardiac anisotropy on cell transplantation for myocardial repair. Here, we hypothesized that a graft's anisotropy of myofiber orientation determines the mechano-electrical characteristics and the therapeutic efficacy. We developed aligned- and random-orientated nanofibrous electrospun patches (aEP and rEP, respectively) with or without seeding of cardiomyocytes (CMs) and endothelial cells (ECs) to test this hypothesis. Atomic force microscopy showed a better beating frequency and amplitude of CMs when cultured on aEP than that from cells cultured on rEP. For the in vivo test, a total of 66 rats were divided into six groups: sham, myocardial infarction (MI), MI + aEP, MI + rEP, MI + CM-EC/aEP and MI + CM-EC/rEP (n ≥ 10 for each group). Implantation of aEP or rEP provided mechanical support and thus retarded functional aggravation at 56 days after MI. Importantly, CM-EC/aEP implantation further improved therapeutic outcomes, while cardiac deterioration occurred on the CM-EC/rEP group. Similar results were shown by hemodynamic and infarct size examination. Another independent in vivo study was performed and electrocardiography and optical mapping demonstrated that there were more ectopic activities and defective electro-coupling after CM-EC/rEP implantation, which worsened cardiac functions. Together these results provide comprehensive functional characterizations and demonstrate the therapeutic efficacy of a nanopatterned anisotropic cardiac patch. Importantly, the study confirms the significance of cardiac anisotropy recapitulation in myocardial tissue engineering, which is valuable for the future development of translational nanomedicine.

13.
Sci Transl Med ; 4(146): 146ra109, 2012 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-22875829

RESUMEN

Angiogenic therapy is a promising approach for tissue repair and regeneration. However, recent clinical trials with protein delivery or gene therapy to promote angiogenesis have failed to provide therapeutic effects. A key factor for achieving effective revascularization is the durability of the microvasculature and the formation of new arterial vessels. Accordingly, we carried out experiments to test whether intramyocardial injection of self-assembling peptide nanofibers (NFs) combined with vascular endothelial growth factor (VEGF) could create an intramyocardial microenvironment with prolonged VEGF release to improve post-infarct neovascularization in rats. Our data showed that when injected with NF, VEGF delivery was sustained within the myocardium for up to 14 days, and the side effects of systemic edema and proteinuria were significantly reduced to the same level as that of control. NF/VEGF injection significantly improved angiogenesis, arteriogenesis, and cardiac performance 28 days after myocardial infarction. NF/VEGF injection not only allowed controlled local delivery but also transformed the injected site into a favorable microenvironment that recruited endogenous myofibroblasts and helped achieve effective revascularization. The engineered vascular niche further attracted a new population of cardiomyocyte-like cells to home to the injected sites, suggesting cardiomyocyte regeneration. Follow-up studies in pigs also revealed healing benefits consistent with observations in rats. In summary, this study demonstrates a new strategy for cardiovascular repair with potential for future clinical translation.


Asunto(s)
Nanofibras/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Animales , Masculino , Infarto del Miocardio/terapia , Miocardio/patología , Neovascularización Fisiológica/efectos de los fármacos , Ratas , Factor A de Crecimiento Endotelial Vascular/química
14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 11): m1346, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23284334

RESUMEN

The title salt, [Ru(Tp)(CH(5)N)(2)(PPh(3))]Cl·CH(2)Cl(2)·H(2)O [where Tp is (C(3)H(3)N(2))(3)BH and PPH(3) is C(18)H(15)P], has the Ru(III) atom in an octa-hedral geometry; one of the Ru-N(Tp) bonds [2.135 (8) Å] is slightly longer than another two, owing to the trans influence of PPh(3) ligand. N-H⋯Cl and O-H⋯Cl hydrogen bonding leads to the formation of layers parallel to (100).

15.
Circulation ; 122(11 Suppl): S132-41, 2010 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-20837904

RESUMEN

BACKGROUND: Growing evidence suggests that intramyocardial biomaterial injection improves cardiac functions after myocardial infarction (MI) in rodents. Cell therapy is another promising approach to treat MI, although poor retention of transplanted cells is a major challenge. In this study, we hypothesized that intramyocardial injection of self-assembling peptide nanofibers (NFs) thickens the infarcted myocardium and increases transplanted autologous bone marrow mononuclear cell (MNC) retention to attenuate cardiac remodeling and dysfunction in a pig MI model. METHODS AND RESULTS: A total of 40 mature minipigs were divided into 5 groups: sham, MI+normal saline, MI+NFs, MI+MNCs, and MI+MNCs/NFs. MI was induced by coronary occlusion followed by intramyocardial injection of 2 mL normal saline or 1% NFs with or without 1×10(8) isolated autologous MNCs. NF injection significantly improved diastolic function and reduced ventricular remodeling 28 days after treatment. Injection of MNCs alone ameliorated systolic function only, whereas injection of MNCs with NFs significantly improved both systolic and diastolic functions as indicated by +dP/dt and -dP/dt (1214.5±91.9 and -1109.7±91.2 mm Hg/s in MI+NS, 1693.7±84.7 and -1809.6±264.3 mm Hg/s in MI+MNCs/NFs, respectively), increased transplanted cell retention (29.3±4.5 cells/mm(2) in MI+MNCs and 229.4±41.4 cells/mm(2) in MI+MNCs/NFs) and promoted capillary density in the peri-infarct area. CONCLUSIONS: We demonstrated that NF injection alone prevents ventricular remodeling, whereas cell implantation with NFs improves cell retention and cardiac functions after MI in pigs. This unprecedented combined treatment in a large animal model has therapeutic effects, which can be translated to clinical applications in the foreseeable future.


Asunto(s)
Trasplante de Médula Ósea , Infarto del Miocardio/terapia , Nanofibras/administración & dosificación , Péptidos/administración & dosificación , Remodelación Ventricular/efectos de los fármacos , Animales , Humanos , Infarto del Miocardio/fisiopatología , Porcinos , Porcinos Enanos , Trasplante Autólogo
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