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1.
iScience ; 27(9): 110671, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39262796

RESUMEN

Previous studies have indicated that various blood cell traits are associated with a higher risk of venous thromboembolism (VTE). However, the causal relationship remains uncertain. We collected data from the China pulmonary thromboembolism registry study and the China pulmonary health study, using propensity score matching and two-sample Mendelian randomization analyses with summary statistics from genome-wide association studies of blood cell traits and VTE in the East Asian population. Our findings revealed that platelet (PLT) count and hemoglobin (Hb) levels were significantly higher in VTE patients compared to the general population (p value <0.01). Genetically predicted Hb levels were positively associated with VTE, with an odds ratio (OR) of 2.38 (1.13-5.01), p value = 0.022. Similarly, genetically predicted PLT count was positively correlated with VTE, with an OR of 1.33 (1.02-1.74), p value = 0.038. These results suggest a causal relationship and potential targets for prevention.

2.
Adv Sci (Weinh) ; : e2407598, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39231320

RESUMEN

Realization of the full potential of single-atom photoelectrocatalysts in sustainable energy generation requires careful consideration of the design of the host material. Here, a comprehensive methodology for the rational design of photoelectrocatalysts using anodic titanium dioxide (TiO2) nanofilm as a model platform is presented. The properties of these nanofilms are precisely engineered to elucidate synergies across structural, chemical, optoelectronic, and electrochemical properties to maximize the efficiency of the hydrogen evolution reaction (HER). These findings clearly demonstrate that thicker TiO2 nanofilms in anatase phase with pits on the surface can accommodate single-atom platinum catalysts in an optimal configuration to increase HER performance. It is also evident that the electrolyte temperature can further enhance HER output through thermochemical effect. A judicious design incorporating all these factors into one system gives rise to a ten-fold HER enhancement. However, the reusability of the host photoelectrocatalyst is limited by the leaching of the Pt atom, worsening HER. Density-functional theory calculations have provided insights into the mechanism underlying the experimental observations in terms of moderate hydrogen adsorption and enhanced gas generation. This improved understanding of the critical factors determining HER performance in a model photoelectrocatalyst paves the way for future advances in scalable and translatable photoelectrocatalyst technologies.

3.
Sensors (Basel) ; 24(16)2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39205143

RESUMEN

This study introduces an innovative approach by incorporating statistical offset features, range profiles, time-frequency analyses, and azimuth-range-time characteristics to effectively identify various human daily activities. Our technique utilizes nine feature vectors consisting of six statistical offset features and three principal component analysis network (PCANet) fusion attributes. These statistical offset features are derived from combined elevation and azimuth data, considering their spatial angle relationships. The fusion attributes are generated through concurrent 1D networks using CNN-BiLSTM. The process begins with the temporal fusion of 3D range-azimuth-time data, followed by PCANet integration. Subsequently, a conventional classification model is employed to categorize a range of actions. Our methodology was tested with 21,000 samples across fourteen categories of human daily activities, demonstrating the effectiveness of our proposed solution. The experimental outcomes highlight the superior robustness of our method, particularly when using the Margenau-Hill Spectrogram for time-frequency analysis. When employing a random forest classifier, our approach outperformed other classifiers in terms of classification efficacy, achieving an average sensitivity, precision, F1, specificity, and accuracy of 98.25%, 98.25%, 98.25%, 99.87%, and 99.75%, respectively.


Asunto(s)
Algoritmos , Análisis de Componente Principal , Humanos , Actividades Humanas/clasificación , Radar , Redes Neurales de la Computación , Actividades Cotidianas
4.
J Am Chem Soc ; 146(32): 22850-22858, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39096280

RESUMEN

Carbon-carbon (C-C) coupling is essential in the electrocatalytic reduction of CO2 for the production of green chemicals. However, due to the complexity of the reaction network, there remains controversy regarding the underlying reaction mechanisms and the optimal direction for catalyst material design. Here, we present a global perspective to establish a comprehensive data set encompassing all C-C coupling precursors and catalytic active site compositions to explore the reaction mechanisms and screen catalysts via big data set analysis. The 2D-3D ensemble machine learning strategy, developed to target a variety of adsorption configurations, can quickly and accurately expand quantum chemical calculation data, enabling the rapid acquisition of this extensive big data set. Analyses of the big data set establish that (1) asymmetric coupling mechanisms exhibit greater potential efficiency compared to symmetric coupling, with the optimal path involving the coupling CHO with CH or CH2, and (2) C-C coupling selectivity of Cu-based catalysts can be enhanced through bimetallic doping including CuAgNb sites. Importantly, we experimentally substantiate the CuAgNb catalyst to demonstrate actual boosted performance in C-C coupling. Our finding evidence the practicality of our big data set generated from machine learning-accelerated quantum chemical computations. We conclude that combining big data with complex catalytic reaction mechanisms and catalyst compositions will set a new paradigm for accelerating optimal catalyst design.

5.
J Colloid Interface Sci ; 676: 261-271, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39029252

RESUMEN

Multifunctional electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) are crucial for development of the key electrochemical energy storage and conversion devices, for which single-atom catalyst (SAC) has present great promises. Very recently, some experimental works showed that structurally well-defined ultra-small transition-metal clusters (such as Fe and Co tetramers, denoted as Fe4 and Co4, respectively), can efficiently modulate the catalytic behavior of SACs by axial coordination. Herein, taking the graphene-supported MN4 SACs as representatives, we theoretically explored the feasibility of realizing multifunctional SACs for ORR, OER and HER by this novel axial coordination engineering. Through extensive first-principles calculations, from 23 candidates, IrN4 decorated with Fe4 (IrN4/Fe4) is identified as the promising trifunctional catalyst with the theoretical overpotential of 0.43, 0.51 and 0.30 V for OER, ORR and HER, respectively. RhN4/Fe4 and CoN4/Fe4 are recognized as potential OER and ORR bifunctional catalysts. In addition, NiN4/Fe4 exhibits the best ORR activity with an overpotential of 0.30 V, far superior to the pristine NiN4 SAC (0.88 V). Electronic structure analyses reveal that the significantly enhanced ORR/OER activity can be ascribed to the orbital and charge redistribution of Ni/Ir active center, resulting from its electronic interaction with Fe4 cluster. This work could stimulate and guide the rational design of graphene-based multifunctional SACs realized by axial coordination of small TM clusters, and provide insights into the modulation mechanism.

6.
Small ; : e2404065, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949396

RESUMEN

Fe3O4 is barely taken into account as an electrocatalyst for oxygen reduction reaction (ORR), an important reaction for metal-air batteries and fuel cells, due to its sluggish catalytic kinetics and poor electron conductivity. Herein, how strain engineering can be employed to regulate the local electronic structure of Fe3O4 for high ORR activity is reported. Compressively strained Fe3O4 shells with 2.0% shortened Fe─O bond are gained on the Fe/Fe4N cores as a result of lattice mismatch at the interface. A downshift of the d-band center occurs for compressed Fe3O4, leading to weakened chemisorption energy of oxygenated intermediates, and lower reaction overpotential. The compressed Fe3O4 exhibits greatly enhanced electrocatalytic ORR activity with a kinetic current density of 27 times higher than that of pristine one at 0.80 V (vs reversible hydrogen electrode), as well as potential application in zinc-air batteries. The findings provide a new strategy for tuning electronic structures and improving the catalytic activity of other metal catalysts.

7.
Cardiovasc Res ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38918884

RESUMEN

Cardiac aging is an intricate and multifaceted process with considerable impact on public health, especially given the global demographic shift towards aged populations. This review discusses structural, cellular and functional changes associated with cardiac aging and heart failure with preserved ejection fraction (HFpEF). Key molecular mediators are considered within the framework of the established hallmarks of aging, with particular attention to promising therapeutic candidates. We further delineate the differential impacts of aging on cardiac structure and function in men and women, addressing hormonal and chromosomal influences. The protective and mitigating effects of exercise in cardiac aging and HFpEF in particular are discussed, as an inspiration for the identification of pathways that mitigate biological aging. We also emphasize how much remains to be learned and the importance of these efforts in enhancing the cardiac health of aging populations worldwide.

8.
Adv Sci (Weinh) ; 11(32): e2401331, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38923788

RESUMEN

Thermal switches that switch the thermal conductivity (κ) of the active layers are attracting increasing attention as thermal management devices. For electrochemical thermal switches, several transition metal oxides (TMOs) are proposed as active layers. After electrochemical redox treatment, the crystal structure of the TMO is modulated, which results in the κ switching. However, the κ switching width is still small (<4 W m-1 K-1). In this study, it demonstrates that LaNiOx-based solid-state electrochemical thermal switches have a κ switching width of 4.3 W m-1 K-1. Fully oxidized LaNiO3 (on state) has a κ of 6.0 W m-1 K-1 due to the large contribution of electron thermal conductivity (κele, 3.1 W m-1 K-1). In contrast, reduced LaNiO2.72 (off state) has a κ of 1.7 W m-1 K-1 because the phonons are scattered by the oxygen vacancies. The LaNiOx-based electrochemical thermal switch is cyclable of κ and the crystalline lattice of LaNiOx. This electrochemical thermal switch may be a promising platform for next-generation devices such as thermal displays.

9.
Cancer Res ; 84(14): 2265-2281, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38718296

RESUMEN

Circadian clock perturbation frequently occurs in cancer and facilitates tumor progression by regulating malignant growth and shaping the immune microenvironment. Emerging evidence has indicated that clock genes are disrupted in melanoma and linked to immune escape. Herein, we found that the expression of retinoic acid receptor-related orphan receptor-α (RORA) is downregulated in melanoma patients and that patients with higher RORA expression have a better prognosis after immunotherapy. Additionally, RORA was significantly positively correlated with T-cell infiltration and recruitment. Overexpression or activation of RORA stimulated cytotoxic T-cell-mediated antitumor responses. RORA bound to the CD274 promoter and formed an inhibitory complex with HDAC3 to suppress PD-L1 expression. In contrast, the DEAD-box helicase family member DDX3X competed with HDAC3 for binding to RORA, and DDX3X overexpression promoted RORA release from the suppressive complex and thereby increased PD-L1 expression to generate an inhibitory immune environment. The combination of a RORA agonist with an anti-CTLA4 antibody synergistically increased T-cell antitumor immunity in vivo. A score based on the combined expression of HDAC3, DDX3X, and RORA correlated with immunotherapy response in melanoma patients. Together, this study elucidates a mechanism of clock component-regulated antitumor immunity, which will help inform the use of immunotherapy and lead to improved outcomes for melanoma patients receiving combined therapeutic treatments. Significance: RORA forms a corepressor complex to inhibit PD-L1 expression and activate antitumor T-cell responses, indicating that RORA is a potential target and predictive biomarker to improve immunotherapy response in melanoma patients.


Asunto(s)
Antígeno B7-H1 , Relojes Circadianos , Melanoma , Humanos , Melanoma/inmunología , Melanoma/patología , Melanoma/genética , Melanoma/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/inmunología , Animales , Ratones , Relojes Circadianos/genética , Relojes Circadianos/inmunología , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Microambiente Tumoral/inmunología , Histona Desacetilasas/metabolismo , Histona Desacetilasas/genética , Monitorización Inmunológica , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Ratones Endogámicos C57BL , Masculino , Femenino , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Inmunoterapia/métodos , Pronóstico
10.
JACC Basic Transl Sci ; 9(4): 535-552, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38680954

RESUMEN

Among its many cardiovascular benefits, exercise training improves heart function and protects the heart against age-related decline, pathological stress, and injury. Here, we focus on cardiac benefits with an emphasis on more recent updates to our understanding. While the cardiomyocyte continues to play a central role as both a target and effector of exercise's benefits, there is a growing recognition of the important roles of other, noncardiomyocyte lineages and pathways, including some that lie outside the heart itself. We review what is known about mediators of exercise's benefits-both those intrinsic to the heart (at the level of cardiomyocytes, fibroblasts, or vascular cells) and those that are systemic (including metabolism, inflammation, the microbiome, and aging)-highlighting what is known about the molecular mechanisms responsible.

11.
Opt Express ; 32(4): 5770-5782, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439295

RESUMEN

In this work, we propose an analytical expression for calculating the transverse mode instability (TMI) threshold power, which clearly shows the role of various fiber parameters and system parameters. The TMI threshold expression is obtained by solving the heat conduction equation and the nonlinear coupling equation using the fundamental mode fitted by Gaussian functions. The calculation results of the proposed TMI threshold expression are consistent with the experimental phenomena and simulation results from the well-recognized theoretical model. The influence of some special parameters on the TMI threshold and the power scaling is also investigated. This work will be helpful for fiber design and TMI mitigation of high-power fiber lasers.

12.
Nanoscale ; 16(14): 7058-7067, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38445992

RESUMEN

The electrocatalytic NO reduction reaction (NORR) emerges as an intriguing strategy to convert harmful NO into valuable NH3. Due to their unique intrinsic properties, graphene-based Fe single-atom catalysts (SACs) have gained considerable attention in electrocatalysis, while their potential for NORR and the underlying mechanism remain to be explored. Herein, using constant-potential density functional theory calculations, we systematically investigated the electrocatalytic NORR on the graphene-based Fe SACs. By changing the local coordination environment of Fe single atoms, 26 systems were constructed. Theoretical results show that, among these systems, the Fe SAC coordinated with four pyrrole N atoms and that co-coordinated with three pyridine N atoms and one O atom exhibit excellent NORR activity with low limiting potentials of -0.26 and -0.33 V, respectively, as well as have high selectivity toward NH3 by inhibiting the formation of byproducts, especially under applied potential. Furthermore, electronic structure analyses indicate that NO molecules can be effectively adsorbed and activated via the electron "donation-backdonation" mechanism. In particular, the d-band center of the Fe SACs was identified as an efficient catalytic activity descriptor for NORR. Our work could stimulate and guide the experimental exploration of graphene-based Fe SACs for efficient NORR toward NH3 under ambient conditions.

13.
Angew Chem Int Ed Engl ; 63(14): e202319091, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308095

RESUMEN

Aqueous zinc-ion batteries are regarded as promising and efficient energy storage systems owing to remarkable safety and satisfactory capacity. Nevertheless, the instability of zinc metal anodes, characterized by issues such as dendrite growth and parasitic side reactions, poses a significant barrier to widespread applications. Herein, we address this challenge by designing a localized conjugated structure comprising a cyclic polyacrylonitrile polymer (CPANZ), induced by a Zn2+-based Lewis acid (zinc trifluoromethylsulfonate) at a temperature of 120 °C. The CPANZ layer on the Zn anode, enriched with appropriate pyridine nitrogen-rich groups (conjugated cyclic -C=N-), exhibits a notable affinity for Zn2+ with ample deposition sites. This zincophilic skeleton not only serves as a protective layer to guide the deposition of Zn2+ but also functions as proton channel blocker, regulating the proton flux to mitigate the hydrogen evolution. Additionally, the strong adhesion strength of the CPANZ layer guarantees its sustained protection to the Zn metal during long-term cycling. As a result, the modified zinc electrode demonstrates long cycle life and high durability in both half-cell and pouch cells. These findings present a feasible approach to designing high performance aqueous anodes by introducing a localized conjugated layer.

14.
Am J Physiol Heart Circ Physiol ; 326(3): H832-H844, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38305752

RESUMEN

Cardiac aging is a multifaceted process that encompasses structural and functional alterations culminating in heart failure. As the elderly population continues to expand, there is a growing urgent need for interventions to combat age-related cardiac functional decline. Noncoding RNAs have emerged as critical regulators of cellular and biochemical processes underlying cardiac disease. This review summarizes our current understanding of how noncoding RNAs function in the heart during aging, with particular emphasis on mechanisms of RNA modification that control their activity. Targeting noncoding RNAs as potential novel therapeutics in cardiac aging is also discussed.


Asunto(s)
Insuficiencia Cardíaca , ARN Largo no Codificante , Humanos , Anciano , ARN Largo no Codificante/genética , ARN no Traducido/genética , Corazón , Envejecimiento/genética , Insuficiencia Cardíaca/genética
15.
iScience ; 27(2): 108930, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38333700

RESUMEN

Determining novel biomarkers for early identification of chronic thromboembolic pulmonary hypertension (CTEPH) could improve patient outcomes. We used the isobaric tag for relative and absolute quantitation approach to compare the serum protein profiles between CTEPH patients and the controls. Bioinformatics analyses and ELISA were also performed. We identified three proteins including heparanase (HPSE), gelsolin (GSN), and secreted protein acidic and rich in cysteine (SPARC) had significant changes in CTEPH. The receiver operating characteristic curve analysis showed that the areas under the curve of HPSE in CTEPH diagnosis were 0.988. Furthermore, HPSE was correlated with multiple parameters of right ventricular function. HPSE concentrations were significantly higher in patients with a low TAPSE/sPAP ratio (≤0.31 mm/mmHg) (65.4 [60.5,68.0] vs. 59.9 [35.9,63.2] ng/mL, p < 0.05). The CTEPH patients treated by balloon pulmonary angioplasty had significantly lower HPSE levels. The study demonstrates that HPSE may be a promising biomarker for noninvasive detection of CTEPH.

16.
Pulm Circ ; 14(1): e12327, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38162296

RESUMEN

Balloon pulmonary angioplasty (BPA) has been proven effective for addressing technically inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, the effectiveness of BPA in technically operable CTEPH patients who, for various reasons, did not undergo the procedure remains an area requiring exploration. This study sought to assess the safety and efficacy of BPA in such cases. We collected and reviewed data from CTEPH patients who underwent BPA in a consecutive manner. Following multidisciplinary team (MDT) decisions, patients were classified into two groups: technically inoperable (group A) and operable (group B). Group B comprised patients deemed technically suitable for pulmonary endarterectomy (PEA) but who did not undergo the procedure for various reasons. All patients underwent a comprehensive diagnostic work-up, including right heart categorization at baseline and the last intervention. This study compared changes in hemodynamic parameters, functional capacity, and quality of life between the two groups. In total, 161 patients underwent 414 procedures at our center, with Group A comprising 112 patients who underwent 282 BPA sessions and group B comprising 49 patients who underwent 132 BPA sessions. Significantly, both groups exhibited improvements in hemodynamics, functional capacity, and quality of life. The occurrence rate of complications, including hemoptysis and lung injury, was similar [12 (63.2%) vs. 7 (36.8%), p = 0.68]. BPA demonstrated favorable outcomes in patients with proximal CTEPH who did not undergo pulmonary endarterectomy. However, the clinical impact of BPA in technically operable CTEPH was found to be less significant than in inoperable cases.

17.
RSC Adv ; 14(6): 3909-3922, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38283590

RESUMEN

Perovskite oxides are extensively utilized in energy storage and conversion. However, they are conventionally screened via time-consuming and cost-intensive experimental approaches and density functional theory. Herein, interpretable machine learning is applied to identify perovskite oxides from virtual perovskite-type combinations by constructing classification and regression models to predict their thermodynamic stability and energy above the convex hull (Eh), respectively, and interpreting the models using SHapley Additive exPlanations. The highest occupied molecular orbital energy and the elastic modulus of the B-site elements of perovskite oxides are the top two features for stability prediction, whereas the Stability Label and features involving the elastic modulus and ionic radius are crucial for Eh regression. A classification model, which displays an accuracy of 0.919, precision of 0.937, F1-score of 0.932, and recall of 0.935, screens 682 143 stable perovskite oxides from 1 126 668 virtual perovskite-type combinations. The Eh values of the predicted stable perovskites are forecasted by a regression model with a coefficient of determination of 0.916, and root mean square error of 24.2 meV atom-1. Good agreement is observed between the regression model predicted and density functional theory-calculated Eh values.

18.
Nat Mater ; 23(2): 182-188, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38182809

RESUMEN

Multiferroic materials, particularly those possessing simultaneous electric and magnetic orders, offer a platform for design technologies and to study modern physics. Despite the substantial progress and evolution of multiferroics, one priority in the field remains to be the discovery of unexplored materials, especially those offering different mechanisms for controlling electric and magnetic orders1. Here we demonstrate the simultaneous thermal control of electric and magnetic polarizations in quasi-two-dimensional halides (K,Rb)3Mn2Cl7, arising from a polar-antipolar transition, as evidenced using both X-ray and neutron powder diffraction data. Our density functional theory calculations indicate a possible polarization-switching path including a strong coupling between the electric and magnetic orders in our halide materials, suggesting a magnetoelectric coupling and a situation not realized in oxide analogues. We expect our findings to stimulate the exploration of non-oxide multiferroics and magnetoelectrics to open access to alternative mechanisms, beyond conventional electric and magnetic control, for coupling ferroic orders.

19.
J Biomed Mater Res A ; 112(5): 700-709, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-37962013

RESUMEN

Sensorineural hearing loss (SNHL) is caused by the loss of sensory hair cells (HCs) and/or connected spiral ganglion neurons (SGNs). The current clinical conventional treatment for SNHL is cochlear implantation (CI). The principle of CI is to bypass degenerated auditory HCs and directly electrically stimulate SGNs to restore hearing. However, the effectiveness of CI is limited when SGNs are severely damaged. In the present study, oriented nanofiber scaffolds were fabricated using electrospinning technology to mimic the SGN spatial microenvironment in the inner ear. Meanwhile, different proportions of polyaniline (PANI), poly-l-lactide (PLLA), gelatin (Gel) were composited to mimic the composition and mechanical properties of auditory basement membrane. The effects of oriented PANI/PLLA/Gel biomimetic nanofiber scaffolds for neurite outgrowth were analyzed. The results showed the SGNs grew in an orientation along the fiber direction, and the length of the protrusions increased significantly on PANI/PLLA/Gel scaffold groups. The 2% PANI/PLLA/Gel group showed best effects for promoting SGN adhesion and nerve fiber extension. In conclusion, the biomimetic oriented nanofiber scaffolds can simulate the microenvironment of SGNs as well as promote neurite outgrowth in vitro, which may provide a feasible research idea for SGN regeneration and even therapeutic treatments of SNHL in future.


Asunto(s)
Compuestos de Anilina , Nanofibras , Poliésteres , Ganglio Espiral de la Cóclea , Ganglio Espiral de la Cóclea/fisiología , Gelatina/farmacología , Neuronas
20.
Cardiovasc Res ; 120(3): 262-272, 2024 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-38084908

RESUMEN

AIMS: Physiological cardiac hypertrophy occurs in response to exercise and can protect against pathological stress. In contrast, pathological hypertrophy occurs in disease and often precedes heart failure. The cardiac pathways activated in physiological and pathological hypertrophy are largely distinct. Our prior work demonstrated that miR-222 increases in exercised hearts and is required for exercise-induced cardiac hypertrophy and cardiomyogenesis. Here, we sought to define the role of miR-222 in pathological hypertrophy. METHODS AND RESULTS: We found that miR-222 also increased in pathological hypertrophy induced by pressure overload. To assess its functional significance in this setting, we generated a miR-222 gain-of-function model through cardiac-specific constitutive transgenic miR-222 expression (TgC-miR-222) and used locked nucleic acid anti-miR specific for miR-222 to inhibit its effects. Both gain- and loss-of-function models manifested normal cardiac structure and function at baseline. However, after transverse aortic constriction (TAC), miR-222 inhibition accelerated the development of pathological hypertrophy, cardiac dysfunction, and heart failure. Conversely, miR-222-overexpressing mice had less pathological hypertrophy after TAC, as well as better cardiac function and survival. We identified p53-up-regulated modulator of apoptosis, a pro-apoptotic Bcl-2 family member, and the transcription factors, Hmbox1 and nuclear factor of activated T-cells 3, as direct miR-222 targets contributing to its roles in this context. CONCLUSION: While miR-222 is necessary for physiological cardiac growth, it inhibits cardiac growth in response to pressure overload and reduces adverse remodelling and cardiac dysfunction. These findings support the model that physiological and pathological hypertrophy are fundamentally different. Further, they suggest that miR-222 may hold promise as a therapeutic target in pathological cardiac hypertrophy and heart failure.


Asunto(s)
Cardiopatías , Insuficiencia Cardíaca , MicroARNs , Ratones , Animales , MicroARNs/genética , Cardiomegalia/metabolismo , Insuficiencia Cardíaca/metabolismo , Corazón , Cardiopatías/patología , Miocitos Cardíacos/metabolismo , Modelos Animales de Enfermedad , Proteínas de Homeodominio/metabolismo
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