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1.
Rev Cardiovasc Med ; 22(3): 1009-1017, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34565102

RESUMO

The aim of this study was to investigate the correlation between v-set and transmembrane domain-containing 1 (VSTM1) expression and incidence of major adverse cardiac events (MACE) in patients with coronary heart disease (CHD). A total of 310 patients were divided into a non-acute coronary syndrome (non-ACS) group (containing the stable angina group, and the asymptomatic coronary artery diseaseand other patients group) and an ACS group (containing unstable angina and acute myocardial infarction patients). Monocytic VSTM1 expression levels (assessed via average fluorescence intensity derived from antibody binding to VSTM1) in each group were detected and analyzed. The cut-off value of monocytic VSTM1 expression to predict the onset of ACS and MACE was confirmed. VSTM1 expression in monocytes from the ACS group was lower than that of the non-ACS group. The incidence of MACEs in the high VSTM1-expression group was much less than that of those in the low VSTM1 expression group at the 1 year follow-up stage. VSTM1 expression had an independent-inversed association with increased incidence of MACE and ACS. VSTM1 expression in monocytes may help to predict the occurrence of ACS in patients with CHD, and moreover it may provide the means to evaluate MACE prognosis during CHD patient follow-up.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Infarto do Miocárdio , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Humanos , Monócitos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Prognóstico , Fatores de Risco
2.
Transgenic Res ; 30(6): 739-750, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34347236

RESUMO

Our study was aimed to investigate the effects of lgals3a (Gal-3 encoding gene) on the development of zebrafish embryo and its underlying mechanisms. Morpholino (MO) technology was used to inhibit the expression of zebrafish lgals3a, and the effect of lgals3a gene knockdown on zebrafish embryo development and the number of monocyte macrophages was observed. Effect of lgals3a-e3i3-MO on apoptosis of zebrafish was detected by acridine orange staining. In addition, the mRNA expression levels of Wnt/ß-catenin signaling pathway-related genes were detected by RT-qPCR. Compared with control-MO group, the zebrafish embryos injected with lgals3a-e3i3-MO had obvious defects in the head, eyes, and tail, and pericardial edema. Lgals3a-e3i3-MO significantly reduced the number of mononuclear macrophages in zebrafish embryos compared with the control-MO group. The results of acridine orange staining showed that compared with the control-MO group, lgals3a-e3i3-MO promoted cardiomyocyte apoptosis in zebrafish. Furthermore, lgals3a-e3i3-MO significantly up-regulated the expression of dkk1b, wnt9a, lrp5, fzd7a, ß-catenin, Gsk-3ß, mycn, myca in the Wnt/ß-catenin pathway, and decreased the expression of lef1. These results indicate that lgals3a-e3i3-MO inhibits zebrafish embryo development, reduces the number of mononuclear macrophages, activates Wnt/ß-catenin signaling pathway and promotes cardiomyocyte apoptosis.


Assuntos
Peixe-Zebra , beta Catenina , Laranja de Acridina/metabolismo , Laranja de Acridina/farmacologia , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Receptores de Superfície Celular , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas Wnt/farmacologia , Via de Sinalização Wnt/genética , Proteínas de Peixe-Zebra/genética , beta Catenina/genética , beta Catenina/metabolismo
3.
Cell Mol Biol Lett ; 24: 62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798643

RESUMO

BACKGROUND: Myocardial ischaemia reperfusion injury (MIRI) is a difficult problem in clinical practice, and it may involve various microRNAs. This study investigated the role that endogenous microRNA-146a plays in myocardial ischaemia reperfusion and explored the possible target genes. METHODS: MIRI models were established in microRNA-146a deficient (KO) and wild type (WT) mice. MicroRNA-146a expression was evaluated in the myocardium of WT mice after reperfusion. The heart function, area of myocardium infarction and in situ apoptosis were compared between the KO and WT mice. Microarray was used to explore possible target genes of microRNA-146a, while qRT-PCR and dual luciferase reporter assays were used for verification. Western blotting was performed to detect the expression levels of the target gene and related signalling molecules. A rescue study was used for further testing. RESULTS: MicroRNA-146a was upregulated 1 h after reperfusion. MicroRNA-146a deficiency decreased heart function and increased myocardial infarction and apoptosis. Microarray detected 19 apoptosis genes upregulated in the KO mice compared with the WT mice. qRT-PCR and dual luciferase verified that Med1 was one target gene of microRNA-146a. TRAP220, encoded by Med1 in the KO mice, was upregulated, accompanied by an amplified ratio of Bax/Bcl2 and increased cleaved caspase-3. Inhibition of microRNA-146a in H9C2 cells caused increased TRAP220 expression and more apoptosis under the stimulus of hypoxia and re-oxygenation, while knockdown of the increased TRAP220 expression led to decreased cell apoptosis. CONCLUSIONS: MicroRNA-146a exerts a protective effect against MIRI, which might be partially mediated by the target gene Med1 and related to the apoptosis signalling pathway.


Assuntos
Subunidade 1 do Complexo Mediador/genética , MicroRNAs/genética , Infarto do Miocárdio/genética , Traumatismo por Reperfusão Miocárdica/genética , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Apoptose/genética , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Testes de Função Cardíaca , Masculino , Subunidade 1 do Complexo Mediador/antagonistas & inibidores , Subunidade 1 do Complexo Mediador/metabolismo , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Miócitos Cardíacos/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
4.
Chemistry ; 23(61): 15396-15403, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-28608493

RESUMO

We herein report a visible-light-mediated heterogeneous [4+2] annulation of N-cyclobutylanilines with alkynes catalyzed by self-doped Ti3+ @TiO2 . The self-doped Ti3+ @TiO2 is stable under photooxidation conditions, easy to recycle, and can be used multiple times without appreciable loss of activity. Extensive mechanistic studies suggest that the annulation reaction is mediated by singlet oxygen, which is generated through the photosensitization of oxygen in the air by the self-doped Ti3+ @TiO2 . In contrast, the homogeneous variant catalyzed by a far more expensive iridium complex proceeds under an inert atmosphere, which indicates a different mechanism. The substrate scopes of the two processes are comparable.

5.
Chemistry ; 23(49): 11913-11919, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28799213

RESUMO

The development of novel photocatalysts usually centers on features such as band structures, various nano-, micro-, or macro-forms, and composites in efforts to tune their light absorption and charge separation efficiency. In comparison, the selectivity of photocatalysts with respect to features of reactants such as size and charge has received much less attention, in part due to the difficulty in designing semiconducting photocatalysts with uniform pore size. Here, we use crystalline porous chalcogenides as a platform to probe reactant selectivity in photocatalytic processes. The 3-in-1 integration of high surface area, uniform porosity, and favorable band structures in such chalcogenides makes them excellent candidates for efficient and selective photocatalytic processes. We show that their photocatalytic activity and selectivity are closely related to their differing affinity and selectivity for different guest species. In particular, unlike common solid-state photocatalysts with neutral framework, the anionic nature of the porous chalcogenide framework used here endows them with a high degree of selectivity for cationic species in both guest exchange and closely coupled photocatalytic transformation of such guests. Another interesting discovery is the observation of an unusual ion exchange process involving a transient state of over-saturation of exchanged ions, which can be explained by a transition from an initially kinetically controlled process to a subsequent thermodynamically controlled one. This work is part of ongoing efforts to contribute to the development of a new generation of crystalline porous photocatalysts with custom-designed selectivity for various reactants or products.

6.
Langmuir ; 33(47): 13634-13639, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29139299

RESUMO

Developing photoanodes with efficient visible-light harvesting and excellent charge separation still remains a key challenge in photoelectrochemical water splitting. Here zeolite-type chalcogenide CPM-121 is integrated with TiO2 nanowires to form a heterostructured photoanode, in which crystalline CPM-121 particles serve as a visible light absorber and TiO2 nanowires serve as an electron conductor. Owing to the small band gap of chalcogenides, the hybrid electrode demonstrates obvious absorption in visible-light range. Electrochemical impedance spectroscopy (EIS) shows that electron transport in the hybrid electrode has been significantly facilitated due to the heterojunction formation. A >3-fold increase in photocurrent is observed on the hybrid electrode under visible-light illumination when it is used as a photoanode in a neutral electrolyte without sacrificial agents. This study opens up a new avenue to explore the potential applications of crystalline porous chalcogenide materials for solar-energy conversion in photoelectrochemistry.

7.
J Am Chem Soc ; 138(46): 15102-15105, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933883

RESUMO

Pore space partition, especially the one using C3-symmetric 2,4,6-tri(4-pyridyl)-1,3,5-triazine as pore-partition agent in MIL-88 type (the acs net), has been shown to dramatically enhance CO2 uptake to near-record values. The continued advance in property engineering via pore space partition would depend on intelligent design of both framework components and pore-partition agent. Here, we report a new advance in the design of pore-partition agent by demonstrating a symmetry-guided pathway to develop a large variety of di- and trinuclear 1,2,4-triazolate-based clusters for use as pore-partition agent. The use of metal-organic clusters (instead of organic ligands) as pore-partition agent gives rise to many new pore-partitioned materials with huge compositional variety. The full assembly involves the simultaneous formation of two separate coordination architectures (i.e., the 3-D acs framework and 0-D triazolate clusters) and the eventual welding between the acs framework and triazolate clusters. The wide range of new compositions and structures provides a high degree of tunability in gas sorption properties.

8.
J Am Chem Soc ; 138(8): 2524-7, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26894827

RESUMO

Despite their having much greater potential for compositional and structural diversity, heterometallic metal-organic frameworks (MOFs) reported so far have lagged far behind their homometallic counterparts in terms of CO2 uptake performance. Now the power of heterometallic MOFs is in full display, as shown by a series of new materials (denoted CPM-200s) with superior CO2 uptake capacity (up to 207.6 cm(3)/g at 273 K and 1 bar), close to the all-time record set by MOF-74-Mg. The isosteric heat of adsorption can also be tuned from -16.4 kJ/mol for CPM-200-Sc/Mg to -79.6 kJ/mol for CPM-200-V/Mg. The latter value is the highest reported for MOFs with Lewis acid sites. Some members of the CPM-200s family consist of combinations of metal ions (e.g., Mg/Ga, Mg/Fe, Mg/V, Mg/Sc) that have never been shown to coexist in any known crystalline porous materials. Such previously unseen combinations become reality through a cooperative crystallization process, which leads to the most intimate form of integration between even highly dissimilar metals, such as Mg(2+) and V(3+). The synergistic effects of heterometals bestow CPM-200s with the highest CO2 uptake capacity among known heterometallic MOFs and place them in striking distance of the all-time CO2 uptake record.

9.
Angew Chem Int Ed Engl ; 55(8): 2768-72, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26847038

RESUMO

Cationic frameworks can selectively trap anions through ion exchange, and have applications in ion chromatography and drug delivery. However, cationic frameworks are much rarer than anionic or neutral ones. Herein, we propose a concept, preemptive coordination (PC), for targeting positively charged metal-organic frameworks (P-MOFs). PC refers to proactive blocking of metal coordination sites to preclude their occupation by neutralizing ligands such as OH(-) . We use 20 MOFs to show that this PC concept is an effective approach for developing P-MOFs whose high stability, porosity, and anion-exchange capability allow immobilization of anionic nucleotides and coenzymes, in addition to charge- and size-selective capture or separation of organic dyes. The CO2 and C2 H2 uptake capacity of 117.9 cm(3) g(-1) and 148.5 cm(3) g(-1) , respectively, at 273 K and 1 atm, is exceptionally high among cationic framework materials.

10.
J Am Chem Soc ; 137(19): 6184-7, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25950820

RESUMO

High-silica zeolites, as exemplified by ZSM-5, with excellent chemical and thermal stability, have generated a revolution in industrial catalysis. In contrast, prior to this work, high-silica-zeolite-like chalcogenides based on germanium/tin remained unknown, even after decades of research. Here six crystalline high-germanium or high-tin zeolite-type sulfides and selenides with four different topologies are reported. Their unprecedented framework compositions give these materials much improved thermal and chemical stability with high surface area (Langmuir surface area of 782 m(2)/g(-1)) comparable to or better than zeolites. Among them, highly stable CPM-120-ZnGeS allows for ion exchange with diverse metal or complex cations, resulting in fine-tuning in porosity, fast ion conductivity, and photoelectric response. Being among the most porous crystalline chalcogenides, CPM-120-ZnGeS (exchanged with Cs(+) ions) also shows reversible adsorption with high capacity and affinity for CO2 (98 and 73 cm(3) g(-1) at 273 and 298 K, respectively, isosteric heat of adsorption = 40.05 kJ mol(-1)). Moreover, CPM-120-ZnGeS could also function as a robust photocatalyst for water reduction to generate H2. The overall activity of H2 production from water, in the presence of Na2S-Na2SO3 as a hole scavenger, was 200 µmol h(-1)/(0.10 g). Such catalytic activity remained undiminished under illumination by UV light for as long as measured (200 h), demonstrating excellent resistance to photocorrosion even under intense UV radiation.

11.
J Am Chem Soc ; 137(6): 2235-8, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25651395

RESUMO

Four cubic zirconium-porphyrin frameworks, CPM-99(H2, Zn, Co, Fe), were synthesized by a molecular-configuration-guided strategy. Augmentation of meso-substituted side arms (with double-torsional biphenyl rings) of tetratopic porphyrin linkers leads to a successful implementation of zirconium-carboxylate frameworks with cubic 2.5 nm cage. The hard-templating effect of Zr6-polyoxo-cluster and uniformly embedded (metallo)porphyrin centers endow CPM-99 with highly desirable properties as precursors for oxygen reduction reaction (ORR) catalysts. The pyrolytic products not only retain the microcubic morphology of the parent CPM-99 but also possess porphyrinic active sites, hierarchical porosity, and highly conducting networks. CPM-99Fe-derived material, denoted CPM-99Fe/C, exhibits the best ORR activity, comparable to benchmark 20% Pt/C in alkaline and acidic media, but CPM-99Fe/C is more durable and methanol-tolerant. This work demonstrates a new route for the development of nonprecious metal ORR catalysts from stable metalloporphyrinic MOFs.

12.
Phys Chem Chem Phys ; 17(7): 5202-6, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25601105

RESUMO

Two assemblies, porphyrin powder/ITO and porphyrin film/ITO, were built by a facile method. The time-resolved photovoltage technique was utilized to prove the behaviour of photo-induced charges in the two assemblies. The photovoltage results show that the porphyrin film/ITO assembly displays a reversal polarity response, which is different from the response of porphyrin powder/ITO. This phenomenon is due to the effect of a built-in field on photo-induced charge behaviour at the porphyrin film/ITO interface. This result is beneficial for the development of a measuring method for detecting heterojunction interface formation and understanding the photoelectric process in photoelectric materials and devices.

13.
Angew Chem Int Ed Engl ; 54(27): 7886-90, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-25981827

RESUMO

Metal-organic polyhedra (MOPs) or frameworks (MOFs) based on Cr(3+) are notoriously difficult to synthesize, especially as crystals large enough to be suitable for characterization of the structure or properties. It is now shown that the co-existence of In(3+) and Cr(3+) induces a rapid crystal growth of large single crystals of heterometallic In-Cr-MOPs with the [M8L12] (M=In/Cr, L=dinegative 4,5-imidazole-dicarboxylate) cubane-like structure. With a high concentration of protons from 12 carboxyl groups decorating every edge of the cube and an extensive H-bonded network between cubes and surrounding H2O molecules, the newly synthesized In-Cr-MOPs exhibit an exceptionally high proton conductivity (up to 5.8×10(-2) S cm(-1) at 22.5 °C and 98% relative humidity, single crystal).

14.
J Am Chem Soc ; 136(21): 7579-82, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24836691

RESUMO

Metal-organic frameworks (MOFs) with cationic frameworks and mobile anions have many applications from sensing, anion exchange and separation, to fast ion conductivity. Despite recent progress, the vast majority of MOFs have neutral frameworks. A common mechanism for the formation of neutral frameworks is the attachment of anionic species such as F(-) or OH(-) to the framework metal sites, neutralizing an otherwise cationic scaffolding. Here, we report a general method capable of converting such neutral frameworks directly into cationic ones with concurrent generation of mobile anions. Our method is based on the differential affinity between distinct metal ions with framework anionic species. Specifically, Al(3+) is used to strip F(-) anions away from framework Cr(3+) sites, leading to cationic frameworks with mobile Cl(-) anions. The subsequent anion exchange with OH(-) further leads to a porous network with mobile OH(-) anions. New materials prepared by anion stripping can undergo ion exchange with anionic organic dyes and also exhibit much improved ionic conductivity compared to the original unmodified MOFs.


Assuntos
Eletroquímica , Compostos Organometálicos/química , Ânions , Cátions , Condutividade Elétrica , Hidróxidos , Propriedades de Superfície
15.
J Am Chem Soc ; 136(36): 12572-5, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25164942

RESUMO

Lanthanides (Ln) are a group of important elements usually found in nature as mixtures. Their separation is essential for technological applications but is made challenging by their subtly different properties. Here we report that crystallization of homochiral camphorate metal-organic frameworks (MOFs) is highly sensitive to ionic radii of lanthanides and can be used to selectively crystallize a lanthanide element into predesigned MOFs. Two series of camphorate MOFs were synthesized with acetate (Type 1 with early lanthanides La-Dy) or formate (Type 2 with late lanthanides Tb-Lu and Y) as the auxiliary ligand, respectively. The Ln coordination environment in each type exhibits selectivity for Ln(3+) of different sizes, which could form the basis for a new cost-effective method for Ln separation.

16.
Angew Chem Int Ed Engl ; 53(39): 10485-9, 2014 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-25088748

RESUMO

A new synthetic method to fabricate Ti(3+)-modified, highly stable TiO2 photoanodes for H2O oxidation is reported. With Ti foil as both the conducting substrate and the Ti(3+)/Ti(4+) source, one-dimensional blue Ti(3+)/TiO2 crystals were grown by a one-step hydrothermal reaction. The concentration of Ti(3+) was further tuned by N2H4 reduction, leading to a greater photoelectrocatalytic activity, as evidenced by a high photocurrent density of 0.64 mA cm(-2) at 1.0 V vs RHE under simulated AM 1.5 G illumination. Electron paramagnetic resonance and Mott-Schottky plots reveal that higher charge-carrier density owing to N2H4 reduction contributes to the observed improvement. The generality of this synthesis method was demonstrated by its effectiveness in improving the performance of other types of photoanodes. By integrating the advantages of the 1D TiO2 architecture with those of Ti(3+) self-doping, this work provides a versatile tool toward the fabrication of efficient TiO2 photoanodes.

17.
J Am Chem Soc ; 135(28): 10250-3, 2013 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-23819843

RESUMO

We apply a two-step strategy to realize ordered distribution of multiple components in one nanocluster (NC) with a crystallographically ordered core/shell structure. A coreless supertetrahedral chalcogenide Cd-In-S cluster is prepared, and then a copper ion is inserted at its void core site through a diffusion process to form a Cu-Cd-In-S quaternary NC. This intriguing molecular cluster with mono-copper core and Cd-In shell exhibits enhanced visible-light-responsive optical and photoelectric properties compared to the parent NC.

18.
J Am Chem Soc ; 134(29): 11936-9, 2012 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-22784316

RESUMO

Zeolites are generally made from tetrahedral nodes and ditopic linkers. Reported here is a versatile method based on trifunctional ligands. With this method, two functional groups are used to form zeolitic nets, while the third one serves to immobilize metal clusters within the channels. The process is driven by the coexistence of multiple inorganic building blocks generated in the heterometallic system. The generality of this method is shown by three distinct metal-organic frameworks mimicking AlPO(4)-5 (AFI) and BCT zeotypes as well as the cubic lcs topology. The correlation between the framework topology and trapped metal species reveals the unique bidirectional control (framework topology ↔ confined metal species) that may be exploited to create a large family of zeotypes with channels modified by different metal ions and clusters.

19.
J Inflamm Res ; 15: 2539-2550, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35479829

RESUMO

Objective: Cardiomyocyte apoptosis critically contributes to ischemia reperfusion injury (IRI), which lacks effective therapeutic strategies. Circular RNAs (circRNAs) serve as novel diagnostic and therapeutic targets in various cardiovascular diseases. CircRNA Fbxl5 is one of the abundantly expressed circRNAs in the heart and its role in myocardial IRI remains elusive. Materials and Methods: Wild-type (WT) mice and neonatal mice ventricular myocytes (NMVMs) were used and subjected to myocardial IRI and anoxia reoxygenation (AR), respectively. Molecular and histological analyses and echocardiography were used to determine the extent of apoptosis, infarct size, and cardiac function. Results: We found that circRNA Fbxl5 was significantly upregulated in the myocardium, as well as in NMVMs subjected to AR. Knockdown of circRNA Fbxl5 ameliorated cardiomyocyte apoptosis, thereby decreasing infarct size and preserving cardiac function. Additionally, in vitro knockdown of circRNA Fbxl5 in NMVMs subjected to AR recapitulated the in vivo findings. Mechanistically, we identified that circRNA Fbxl5 directly sponged and suppressed the endogenous microRNA-146a (miR-146a), thereby weakening its inhibitory effect on MED1, which could further promote the apoptosis of cardiomyocytes. Conclusion: Our findings revealed a novel and critical role for circRNA Fbxl5 in regulating cardiomyocyte apoptosis, and added additional insight into circRNAs mediated during myocardial IRI. The underlying miR-146a-MED1 signaling serves as an important cascade in regulating the apoptosis of cardiomyocytes.

20.
World J Stem Cells ; 14(2): 183-199, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35432732

RESUMO

BACKGROUND: Extracellular vesicles (EVs) derived from hypoxia-preconditioned (HP) mesenchymal stem cells (MSCs) have better cardioprotective effects against myocardial infarction (MI) in the early stage than EVs isolated from normoxic (NC)-MSCs. However, the cardioprotective mechanisms of HP-EVs are not fully understood. AIM: To explore the cardioprotective mechanism of EVs derived from HP MSCs. METHODS: We evaluated the cardioprotective effects of HP-EVs or NC-EVs from mouse adipose-derived MSCs (ADSCs) following hypoxia in vitro or MI in vivo, in order to improve the survival of cardiomyocytes (CMs) and restore cardiac function. The degree of CM apoptosis in each group was assessed by the terminal deoxynucleotidyl transferase dUTP nick end-labeling and Annexin V/PI assays. MicroRNA (miRNA) sequencing was used to investigate the functional RNA diversity between HP-EVs and NC-EVs from mouse ADSCs. The molecular mechanism of EVs in mediating thioredoxin-interacting protein (TXNIP) was verified by the dual-luciferase reporter assay. Co-immunoprecipitation, western blotting, and immunofluorescence were performed to determine if TXNIP is involved in hypoxia-inducible factor-1 alpha (HIF-1α) ubiquitination and degradation via the chromosomal region maintenance-1 (CRM-1)-dependent nuclear transport pathway. RESULTS: HP-EVs derived from MSCs reduced both infarct size (necrosis area) and apoptotic degree to a greater extent than NC-EVs from CMs subjected to hypoxia in vitro and mice with MI in vivo. Sequencing of EV-associated miRNAs showed the upregulation of 10 miRNAs predicted to bind TXNIP, an oxidative stress-associated protein. We showed miRNA224-5p, the most upregulated miRNA in HP-EVs, directly combined the 3' untranslated region of TXNIP and demonstrated its critical protective role against hypoxia-mediated CM injury. Our results demonstrated that MI triggered TXNIP-mediated HIF-1α ubiquitination and degradation in the CRM-1-mediated nuclear transport pathway in CMs, which led to aggravated injury and hypoxia tolerance in CMs in the early stage of MI. CONCLUSION: The anti-apoptotic effects of HP-EVs in alleviating MI and the hypoxic conditions of CMs until reperfusion therapy may partly result from EV miR-224-5p targeting TXNIP.

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