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1.
Artículo en Inglés | MEDLINE | ID: mdl-38867666

RESUMEN

Obstructive sleep apnea (OSA), characterized by episodes of intermittent hypoxia (IH), is highly prevalent in patients with abdominal aortic aneurysm (AAA). However, whether IH serves as an independent risk factor for AAA development remains to be investigated. Here, we determined the effects of chronic (6 months) IH on angiotensin (Ang II)-induced AAA development in C57BL/6J male mice, and IH underlying mechanisms in cultured vascular smooth muscle cells (SMCs). IH increased abdominal aortic diameter and the incidence of AAA in mice infused with Ang II as assessed by transabdominal ultrasound imaging. Importantly, IH with Ang II augmented aortic elastin degradation and expression of matrix metalloproteinase (MMP)s, mainly MMP8, MMP12 and a disintegrin and metalloproteinase-17 (ADAM17) as measured by histology and immunohistochemistry. Mechanistically, IH increased the activities of MMP2, MMP8, MMP9, MMP12, and ADAM17, while reducing the expression of the MMP regulator, reversion inducing cysteine rich protein with kazal motifs (RECK) in cultured SMCs. Aortic samples from human AAA were associated with decreased RECK and increased expression of ADAM17 and MMPs. These data suggest that IH promotes the development of AAA in association with an increased expression of MMPs and ADAM17, while decreased expression of RECK may be responsible for the increased protease activity. These findings support a potential causal link between OSA and AAA and provide a better understanding of the molecular mechanisms underlying the pathogenesis of AAA.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38868940

RESUMEN

BACKGROUND: Plasma concentration of PAI-1 (plasminogen activator inhibitor-1) correlates with arterial stiffness. Vascular smooth muscle cells (SMCs) express PAI-1, and the intrinsic stiffness of SMCs is a major determinant of total arterial stiffness. We hypothesized that PAI-1 promotes SMC stiffness by regulating the cytoskeleton and that pharmacological inhibition of PAI-1 decreases SMC and aortic stiffness. METHODS: PAI-039, a specific inhibitor of PAI-1, and small interfering RNA were used to inhibit PAI-1 expression in cultured human SMCs. Effects of PAI-1 inhibition on SMC stiffness, F-actin (filamentous actin) content, and cytoskeleton-modulating enzymes were assessed. WT (wild-type) and PAI-1-deficient murine SMCs were used to determine PAI-039 specificity. RNA sequencing was performed to determine the effects of PAI-039 on SMC gene expression. In vivo effects of PAI-039 were assessed by aortic pulse wave velocity. RESULTS: PAI-039 significantly reduced intrinsic stiffness of human SMCs, which was accompanied by a significant decrease in cytoplasmic F-actin content. PAI-1 gene knockdown also decreased cytoplasmic F-actin. PAI-1 inhibition significantly increased the activity of cofilin, an F-actin depolymerase, in WT murine SMCs, but not in PAI-1-deficient SMCs. RNA-sequencing analysis suggested that PAI-039 upregulates AMPK (AMP-activated protein kinase) signaling in SMCs, which was confirmed by Western blotting. Inhibition of AMPK prevented activation of cofilin by PAI-039. In mice, PAI-039 significantly decreased aortic stiffness and tunica media F-actin content without altering the elastin or collagen content. CONCLUSIONS: PAI-039 decreases intrinsic SMC stiffness and cytoplasmic stress fiber content. These effects are mediated by AMPK-dependent activation of cofilin. PAI-039 also decreases aortic stiffness in vivo. These findings suggest that PAI-1 is an important regulator of the SMC cytoskeleton and that pharmacological inhibition of PAI-1 has the potential to prevent and treat cardiovascular diseases involving arterial stiffening.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38833147

RESUMEN

PURPOSE: The objective of the study is to test the efficacy of cyclopentenyl cytosine (CPEC)-coated stents on blocking artery stenosis, promoting reendothelialization, and reducing thrombosis. METHODS: Scanning electron microscopy was employed to observe the morphological characteristics of stents coated with a mixture of CPEC and poly(lactic-co-glycolic acid) (PLGA) copolymer. PLGA has been used in various Food and Drug Administration (FDA)-approved therapeutic devices. In vitro release of CPEC was tested to measure the dynamic drug elution. Comparison between CPEC- and everolimus-coated stents on neointimal formation and thrombosis formation was conducted after being implanted into the human internal mammary artery and grafted to the mouse aorta. RESULTS: Optimization in stent coating resulted in uniform and consistent coating with minimal variation. In vitro drug release tests demonstrated a gradual and progressive discharge of CPEC. CPEC- or everolimus-coated stents caused much less stenosis than bare-metal stents. However, CPEC stent-implanted arteries exhibited enhanced reendothelialization compared to everolimus stents. Mechanistically, CPEC-coated stents reduced the proliferation of vascular smooth muscle cells while simultaneously promoting reendothelialization. More significantly, unlike everolimus-coated stents, CPEC-coated stents showed a significant reduction in thrombosis formation even in the absence of ongoing anticoagulant treatment. CONCLUSIONS: The study establishes CPEC-coated stent as a promising new device for cardiovascular interventions. By enhancing reendothelialization and preventing thrombosis, CPEC offers advantages over conventional approaches, including the elimination of the need for anti-clogging drugs, which pave the way for improved therapeutic outcomes and management of atherosclerosis-related medical procedures.

4.
Nano Lett ; 24(20): 6158-6164, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38723204

RESUMEN

The gate-all-around (GAA) field-effect transistor (FET) holds great potential to support next-generation integrated circuits. Nanowires such as carbon nanotubes (CNTs) are one important category of channel materials in GAA FETs. Based on first-principles investigations, we propose that SiX2 (X = S, Se) nanowires are promising channel materials that can significantly elevate the performance of GAA FETs. The sub-5 nm SiX2 (X = S, Se) nanowire GAA FETs exhibit excellent ballistic transport properties that meet the requirements of the 2013 International Technology Roadmap for Semiconductors (ITRS). Compared to CNTs, they are also advantageous or at least comparable in terms of gate controllability, device dimensions, etc. Importantly, SiSe2 GAA FETs show superb gate controllability due to the ultralow minimum subthreshold swing (SSmin) that breaks "Boltzmann's tyranny". Moreover, the energy-delay product (EDP) of SiX2 GAA FETs is significantly lower than that of the CNT FETs. These features make SiX2 nanowires ideal channel material in the sub-5 nm GAA FET devices.

5.
Nat Commun ; 15(1): 4344, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773145

RESUMEN

Charge loss at grain boundaries of kesterite Cu2ZnSn(S, Se)4 polycrystalline absorbers is an important cause limiting the performance of this emerging thin-film solar cell. Herein, we report a Pd element assisted reaction strategy to suppress atomic vacancy defects in GB regions. The Pd, on one hand in the form of PdSex compounds, can heterogeneously cover the GBs of the absorber film, suppressing Sn and Se volatilization loss and the formation of their vacancy defects (i.e. VSn and VSe), and on the other hand, in the form of Pd(II)/Pd(IV) redox shuttle, can assist the capture and exchange of Se atoms, thus contributing to eliminating the already-existing VSe defects within GBs. These collective effects have effectively reduced charge recombination loss and enhanced p-type characteristics of the kesterite absorber. As a result, high-performance kesterite solar cells with a total-area efficiency of 14.5% (certified at 14.3%) have been achieved.

6.
bioRxiv ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38617336

RESUMEN

Formation of biomolecular condensates can be driven by weak multivalent interactions and emergent polymerization. However, the mechanism of polymerization-mediated condensate formation is less studied. We found lateral root cap cell (LRC)-specific SUPPRESSOR OF RPS4-RLD1 (SRFR1) condensates fine-tune primary root development. Polymerization of the SRFR1 N-terminal domain is required for both LRC condensate formation and optimal root growth. Surprisingly, the first intrinsically disordered region (IDR1) of SRFR1 can be functionally substituted by a specific group of intrinsically disordered proteins known as dehydrins. This finding facilitated the identification of functional segments in the IDR1 of SRFR1, a generalizable strategy to decode unknown IDRs. With this functional information we further improved root growth by modifying the SRFR1 condensation module, providing a strategy to improve plant growth and resilience.

7.
Sci Rep ; 14(1): 7464, 2024 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-38553537

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) remains the most common cause of liver disease in the United States due to the increased incidence of metabolic dysfunction and obesity. Surfactant protein A (SPA) regulates macrophage function, strongly binds to lipids, and is implicated in renal and idiopathic pulmonary fibrosis (IPF). However, the role of SPA in lipid accumulation, inflammation, and hepatic fibrosis that characterize MASLD remains unknown. SPA deficient (SPA-/-) and age-matched wild-type (WT) control mice were fed a Western diet for 8 weeks to induce MASLD. Blood and liver samples were collected and used to analyze pathological features associated with MASLD. SPA expression was significantly upregulated in livers of mice with MASLD. SPA deficiency attenuated lipid accumulation along with downregulation of genes involved in fatty acid uptake and reduction of hepatic inflammation as evidenced by the diminished macrophage activation, decreased monocyte infiltration, and reduced production of inflammatory cytokines. Moreover, SPA-/- inhibited stellate cell activation, collagen deposit, and liver fibrosis. These results highlight the novel role of SPA in promoting fatty acid uptake into hepatocytes, causing excessive lipid accumulation, inflammation, and fibrosis implicated in the pathogenesis of MASLD.


Asunto(s)
Hígado Graso , Proteína A Asociada a Surfactante Pulmonar , Ratones , Animales , Dieta Occidental/efectos adversos , Hígado Graso/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/complicaciones , Fibrosis , Inflamación/complicaciones , Lípidos , Ácidos Grasos
8.
bioRxiv ; 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38464026

RESUMEN

Aims: The precise molecular drivers of abdominal aortic aneurysm (AAA) remain unclear. Thymidine phosphorylase (TYMP) contributes to increased platelet activation, thrombosis, and inflammation, all of which are key factors in AAA development. Additionally, TYMP suppresses the proliferation of vascular smooth muscle cells (VSMCs), which are central to the development and progression of AAA. We hypothesize that TYMP plays a key role in AAA development. Methods and Results: We conducted a histological study using human AAA samples and normal abdominal aortas, revealing heightened levels of TYMP in human AAA vessel walls. To validate this observation, we utilized an Ang II perfusion-induced AAA model in wild-type C57BL/6J (WT) and Tymp-/- mice, feeding them a Western diet (TD.88137) starting from 4 weeks of age. We found that Tymp-/- mice were protected from Ang II perfusion-induced AAA formation. Furthermore, by using TYMP-expressing VSMCs as well as primarily cultured VSMCs from WT and Tymp-/- mice, we elucidated the essential role of TYMP in regulating MMP2 expression and activation. TYMP deficiency or inhibition by tipiracil, a selective TYMP inhibitor, led to reduced MMP2 production, release, and activation in VSMCs. Additionally, TYMP was found to promote pro-inflammatory cytokine expression systemically, and its absence attenuates TNF-α-stimulated activation of MMP2 and AKT. By co-culturing VSMCs and platelets, we observed that TYMP-deficient platelets had a reduced inhibitory effect on VSMC proliferation compared to WT platelets. Moreover, TYMP appeared to enhance the expression of activated TGFß1 in cultured VSMCs in vitro and in human AAA vessel walls in vivo. TYMP also boosted the activation of thrombospondin-1 type 1 repeat domain-enhanced TGFß1 signaling, resulting in increased connective tissue growth factor production. Conclusion: Our findings collectively demonstrated that TYMP serves as a novel regulatory force in vascular biology, exerting influence over VSMC functionality and inflammatory responses that promote the development of AAA.

9.
Acta Biomater ; 177: 165-177, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38354873

RESUMEN

Four-dimensional (4D) printing unlocks new potentials for personalized biomedical implantation, but still with hurdles of lacking suitable materials. Herein, we demonstrate a bioresorbable shape memory elastomer (SME) with high elasticity at both below and above its phase transition temperature (Ttrans). This SME can be digital light 3D printed by co-polymerizing glycerol dodecanoate acrylate prepolymer (pre-PGDA) with acrylic acid monomer to form crosslinked Poly(glycerol dodecanoate acrylate) (PGDA)-Polyacrylic acid (PAA), or PGDA-PAA network. The printed complex, free-standing 3D structures with high-resolution features exhibit shape programming properties at a physiological temperature. By tuning the pre-PGDA weight ratios between 55 wt% and 70 wt%, Ttrans varies between 39.2 and 47.2 ℃ while Young's moduli (E) range 40-170 MPa below Ttrans with fractural strain (εf) of 170 %-200 %. Above Ttrans, E drops to 1-1.82 MPa which is close to those of soft tissue. Strikingly, εf of 130-180 % is still maintained. In vitro biocompatibility test on the material shows > 90 % cell proliferation and great cell attachment. In vivo vascular grafting trials underline the geometrical and mechanical adaptability of these 4D printed constructs in regenerating the aorta tissue. Biodegradation of the implants shows the possibility of their full replacement by natural tissue over time. To highlight its potential for personalized medicine, a patient-specific left atrial appendage (LAA) occluder was printed and implanted endovascularly into an in vitro heart model. STATEMENT OF SIGNIFICANCE: 4D printed shape-memory elastomer (SME) implants particularly designed and manufactured for a patient are greatly sought-after in minimally invasive surgery (MIS). Traditional shape-memory polymers used in these implants often suffer from issues like unsuitable transition temperatures, poor biocompatibility, limited 3D design complexity, and low toughness, making them unsuitable for MIS. Our new SME, with an adjustable transition temperature and enhanced toughness, is both biocompatible and naturally degradable, particularly in cardiovascular contexts. This allows implants, like biomedical scaffolds, to be programmed at room temperature and then adapt to the body's physiological conditions post-implantation. Our studies, including in vivo vascular grafts and in vitro device implantation, highlight the SME's effectiveness in aortic tissue regeneration and its promising applications in MIS.


Asunto(s)
Elastómeros , Andamios del Tejido , Humanos , Elastómeros/química , Andamios del Tejido/química , Glicerol , Implantes Absorbibles , Lauratos , Impresión Tridimensional , Acrilatos
10.
Anim Nutr ; 16: 105-121, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38357575

RESUMEN

Low-fishmeal and protein-saving diets are two prominent nutritional strategies utilized to address challenges related to the scarcity and sustainability of protein sources in aquaculture. However, these diets have been associated with adverse effects on the growth performance, feed utilization, and disease resistance of aquatic animals. To mitigate these challenges, exogenous protease has been applied to enhance the quality of diets with lower protein contents or fishmeal alternatives, thereby improving the bioavailability of nutritional ingredients. Additionally, protease preparations were also used to enzymatically hydrolyze fishmeal alternatives, thus enhancing their nutritional utilization. The present review aims to consolidate recent research progress on the use of protease in aquaculture and conclude the benefits and limitations of its application, thereby providing a comprehensive understanding of the subject and identifying opportunities for future research.

11.
Cell Biol Toxicol ; 40(1): 13, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38347241

RESUMEN

AIMS: Nuclear protein 1 (Nupr1) is a multifunctional stress-induced protein involved in the regulation of tumorigenesis, apoptosis, and autophagy. However, its role in pulmonary hypertension (PH) after METH exposure remains unexplored. In this study, we aimed to investigate whether METH can induce PH and describe the role and mechanism of Nupr1 in the development of PH. METHODS AND RESULTS: Mice were made to induce pulmonary hypertension (PH) upon chronic intermittent treatment with METH. Their right ventricular systolic pressure (RVSP) was measured to assess pulmonary artery pressure. Pulmonary artery morphometry was determined by H&E staining and Masson staining. Nupr1 expression and function were detected in human lungs, mice lungs exposed to METH, and cultured pulmonary arterial smooth muscle cells (PASMCs) with METH treatment. Our results showed that chronic intermittent METH treatment successfully induced PH in mice. Nupr1 expression was increased in the cultured PASMCs, pulmonary arterial media from METH-exposed mice, and METH-ingested human specimens compared with control. Elevated Nupr1 expression promoted PASMC phenotype change from contractile to synthetic, which triggered pulmonary artery remodeling and resulted in PH formation. Mechanistically, Nupr1 mediated the opening of store-operated calcium entry (SOCE) by activating the expression of STIM1, thereby promoting Ca2+ influx and inducing phenotypic conversion of PASMCs. CONCLUSIONS: Nupr1 activation could promote Ca2+ influx through STIM1-mediated SOCE opening, which promoted METH-induced pulmonary artery remodeling and led to PH formation. These results suggested that Nupr1 played an important role in METH-induced PH and might be a potential target for METH-related PH therapy.


Asunto(s)
Hipertensión Pulmonar , Metanfetamina , Ratones , Humanos , Animales , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/metabolismo , Metanfetamina/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/metabolismo , Células Cultivadas , Arteria Pulmonar/metabolismo , Miocitos del Músculo Liso/metabolismo , Proliferación Celular
12.
Am J Pathol ; 194(4): 599-611, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37838011

RESUMEN

The pathology of atherosclerosis, a leading cause of mortality in patients with cardiovascular disease, involves inflammatory phenotypic changes in vascular endothelial cells. This study explored the role of the dedicator of cytokinesis (DOCK)-2 protein in atherosclerosis. Mice with deficiencies in low-density lipoprotein receptor and Dock2 (Ldlr-/-Dock2-/-) and controls (Ldlr-/-) were fed a high-fat diet (HFD) to induce atherosclerosis. In controls, Dock2 was increased in atherosclerotic lesions, with increased intercellular adhesion molecule (Icam)-1 and vascular cell adhesion molecule (Vcam)-1, after HFD for 4 weeks. Ldlr-/-Dock2-/- mice exhibited significantly decreased oil red O staining in both aortic roots and aortas compared to that in controls after HFD for 12 weeks. In control mice and in humans, Dock2 was highly expressed in the ECs of atherosclerotic lesions. Dock2 deficiency was associated with attenuation of Icam-1, Vcam-1, and monocyte chemoattractant protein (Mcp)-1 in the aortic roots of mice fed HFD. Findings in human vascular ECs in vitro suggested that DOCK2 was required in TNF-α-mediated expression of ICAM-1/VCAM-1/MCP-1. DOCK2 knockdown was associated with attenuated NF-κB phosphorylation with TNF-α, partially accounting for DOCK2-mediated vascular inflammation. With DOCK2 knockdown in human vascular ECs, TNF-α-mediated VCAM-1 promoter activity was inhibited. The findings from this study suggest the novel concept that DOCK2 promotes the pathogenesis of atherosclerosis by modulating inflammation in vascular ECs.


Asunto(s)
Aterosclerosis , Células Endoteliales , Humanos , Animales , Ratones , Células Endoteliales/metabolismo , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo , Aterosclerosis/patología , FN-kappa B/metabolismo , Inflamación/patología , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo
13.
Vascul Pharmacol ; 154: 107270, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38114042

RESUMEN

Adipsin is an adipokine predominantly synthesized in adipose tissues and released into circulation. It is also known as complement factor-D (CFD), acting as the rate-limiting factor in the alternative complement pathway and exerting essential functions on the activation of complement system. The deficiency of CFD in humans is a very rare condition. However, complement overactivation has been implicated in the etiology of numerous disorders, including cardiovascular disease (CVD). Increased circulating level of adipsin has been reported to promote vascular derangements, systemic inflammation, and endothelial dysfunction. Prospective and case-control studies showed that this adipokine is directly associated with all-cause death and rehospitalization in patients with coronary artery disease. Adipsin has also been implicated in pulmonary arterial hypertension, abdominal aortic aneurysm, pre-eclampsia, and type-2 diabetes which is a major risk factor for CVD. Importantly, serum adipsin has been recognized as a unique prognostic marker for assessing cardiovascular diseases. At present, there is paucity of experimental evidence about the precise role of adipsin in the etiology of CVD. However, this mini review provides some insight on the contribution of adipsin in the pathogenesis of CVD and highlights its role on endothelial, smooth muscle and immune cells that mediate cardiovascular functions.


Asunto(s)
Enfermedades Cardiovasculares , Factor D del Complemento , Femenino , Embarazo , Humanos , Factor D del Complemento/metabolismo , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/metabolismo , Estudios Prospectivos , Tejido Adiposo/metabolismo , Adipoquinas/metabolismo
14.
Commun Biol ; 6(1): 1258, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-38086992

RESUMEN

The mechanisms leading to changes in mesoscale chromatin organization during cellular aging are unknown. Here, we used transcriptional activator-like effectors, RNA-seq and superresolution analysis to determine the effects of genotoxic stress on oocyte chromatin structure. Major satellites are organized into tightly packed globular structures that coalesce into chromocenters and dynamically associate with the nucleolus. Acute irradiation significantly enhanced chromocenter mobility in transcriptionally inactive oocytes. In transcriptionally active oocytes, irradiation induced a striking unfolding of satellite chromatin fibers and enhanced the expression of transcripts required for protection from oxidative stress (Fermt1, Smg1), recovery from DNA damage (Tlk2, Rad54l) and regulation of heterochromatin assembly (Zfp296, Ski-oncogene). Non-irradiated, senescent oocytes exhibit not only high chromocenter mobility and satellite distension but also a high frequency of extra chromosomal satellite DNA. Notably, analysis of biological aging using an oocyte-specific RNA clock revealed cellular communication, posttranslational protein modifications, chromatin and histone dynamics as the top cellular processes that are dysregulated in both senescent and irradiated oocytes. Our results indicate that unfolding of heterochromatin fibers following acute genotoxic stress or cellular aging induced the formation of distended satellites and that abnormal chromatin structure together with increased chromocenter mobility leads to chromosome instability in senescent oocytes.


Asunto(s)
Heterocromatina , Oocitos , Animales , Heterocromatina/genética , Heterocromatina/metabolismo , Cromatina/genética , Cromatina/metabolismo , Histonas/metabolismo , Ensamble y Desensamble de Cromatina , Mamíferos/genética
15.
Antioxidants (Basel) ; 12(11)2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-38001821

RESUMEN

To investigate the mechanisms through which ferrous ion (Fe2+) addition improves the utilization of a cottonseed meal (CSM) diet, two experimental diets with equal nitrogen and energy content (low-cottonseed meal (LCM) and high-cottonseed meal (HCM) diets, respectively) containing 16.31% and 38.46% CSM were prepared. Additionally, the HCM diet was supplemented with graded levels of FeSO4·7H2O to establish two different Fe2+ supplementation groups (HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+). Juvenile Ctenopharyngodon idellus (grass carps) (5.0 ± 0.5 g) were fed one of these four diets (HCM, LCM, HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ diets) for eight weeks. Our findings revealed that the HCM diet significantly increased lipid peroxide (LPO) concentration and the expression of lipogenic genes, e.g., sterol regulatory element binding transcription factor 1 (srebp1) and stearoyl-CoA desaturase (scd), leading to excessive lipid droplet deposition in the liver (p < 0.05). However, these effects were significantly reduced in the HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ groups (p < 0.05). Plasma high-density lipoprotein (HDL) concentration was also significantly lower in the HCM and HCM + 0.2%Fe2+ groups compared to the LCM group (p < 0.05), whereas low-density lipoprotein (LDL) concentration was significantly higher in the HCM + 0.2%Fe2+ and HCM + 0.4%Fe2+ groups than in the LCM group (p < 0.05). Furthermore, the plasma levels of liver functional indices, including alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glucose (GLU), were significantly lower in the HCM + 0.4%Fe2+ group (p < 0.05). Regarding the expression of genes related to iron transport regulation, transferrin 2 (tfr2) expression in the HCM group and Fe2+ supplementation groups were significantly suppressed compared to the LCM group (p < 0.05). The addition of 0.4% Fe2+ in the HCM diet activated hepcidin expression and suppressed ferroportin-1 (fpn1) expression (p < 0.05). Compared to the LCM group, the expression of genes associated with ferroptosis and inflammation, including acyl-CoA synthetase long-chain family member 4b (acsl4b), lysophosphatidylcholine acyltransferase 3 (lpcat3), cyclooxygenase (cox), interleukin 1ß (il-1ß), and nuclear factor kappa b (nfκb), were significantly increased in the HCM group (p < 0.05), whereas Fe2+ supplementation in the HCM diet significantly inhibited their expression (p < 0.05) and significantly suppressed lipoxygenase (lox) expression (p < 0.05). Compared with the HCM group without Fe2+ supplementation, Fe2+ supplementation in the HCM diet significantly upregulated the expression of genes associated with ferroptosis, such as heat shock protein beta-associated protein1 (hspbap1), glutamate cysteine ligase (gcl), and glutathione peroxidase 4a (gpx4a) (p < 0.05), and significantly decreased the expression of the inflammation-related genes interleukin 15/10 (il-15/il-10) (p < 0.05). In conclusion, FeSO4·7H2O supplementation in the HCM diet maintained iron transport and homeostasis in the liver of juvenile grass carps, thus reducing the occurrence of ferroptosis and alleviating hepatic lipid deposition and inflammatory responses caused by high dietary CSM contents.

16.
Clinics (Sao Paulo) ; 78: 100285, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37783170

RESUMEN

INTRODUCTION: Long QT Syndrome (LQTS) is an inherited disease with an abnormal electrical conduction system in the heart that can cause sudden death as a result of QT prolongation. LQT2 is the second most common subtype of LQTS caused by loss of function mutations in the potassium voltage-gated channel subfamily H member 2 (KCNH2) gene. Although more than 900 mutations are associated with the LQTS, many of these mutations are not validated or characterized. METHODS AND RESULTS: Sequencing analyses of genomic DNA of a family with LQT2 identified a putative mutation. i.e., KCNH2(NM_000238.3): c.3099_3112del, in KCNH2 gene which appeared to be a definite pathogenic mutation. The family pedigree information showed a gender difference in clinical features and T-wave morphology between male and female patients. The female with mutation exhibited recurring ventricular arrhythmia and syncope, while two male carriers did not show any symptoms. In addition, T-wave in females was much flatter than in males. The female proband showed a positive reaction to the lidocaine test. Lidocaine injection almost completely blocked ventricular arrhythmia and shortened the QT interval by ≥30 ms. Treatment with propranolol, mexiletine, and implantation of cardioverter-defibrillators prevented the sustained ventricular tachycardia, ventricular fibrillation, and syncope, as assessed by a 3-year follow-up evaluation. CONCLUSIONS: A putative mutation c.3099_3112del in the KCNH2 gene causes LQT2 syndrome, and the pathogenic mutation mainly causes symptoms in female progeny.


Asunto(s)
Canales de Potasio Éter-A-Go-Go , Síndrome de QT Prolongado , Humanos , Masculino , Femenino , Canales de Potasio Éter-A-Go-Go/genética , Canal de Potasio ERG1/genética , Factores Sexuales , Mutación/genética , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/diagnóstico , Síncope , Lidocaína
17.
Redox Biol ; 67: 102903, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37801857

RESUMEN

Astrocytes affect stroke outcomes by acquiring functionally dominant phenotypes. Understanding molecular mechanisms dictating astrocyte functional status after brain ischemia/reperfusion may reveal new therapeutic strategies. Adenosine deaminase acting on RNA (ADAR1), an RNA editing enzyme, is not normally expressed in astrocytes, but highly induced in astrocytes in ischemic stroke lesions. The expression of ADAR1 steeply increased from day 1 to day 7 after middle cerebral artery occlusion (MCAO) for 1 h followed by reperfusion. ADAR1 deficiency markedly ameliorated the volume of the cerebral infarction and neurological deficits as shown by the rotarod and cylinder tests, which was due to the reduction of the numbers of activated astrocytes and microglia. Surprisingly, ADAR1 was mainly expressed in astrocytes while only marginally in microglia. In primary cultured astrocytes, ADAR1 promoted astrocyte proliferation via phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Furthermore, ADAR1 deficiency inhibited brain cell apoptosis in mice with MCAO as well as in activated astrocyte-conditioned medium-induced neurons in vitro. It appeared that ADAR1 induces neuron apoptosis by secretion of IL-1ß, IL-6 and TNF-α from astrocytes through the production of reactive oxygen species. These results indicated that ADAR1 is a novel regulator promoting the proliferation of the activated astrocytes following ischemic stroke, which produce various inflammatory cytokines, leading to neuron apoptosis and worsened ischemic stroke outcome.


Asunto(s)
Lesiones Encefálicas , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Daño por Reperfusión , Ratones , Animales , Astrocitos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Isquemia Encefálica/metabolismo , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Neuronas/metabolismo , Apoptosis/genética , Daño por Reperfusión/metabolismo , Adenosina Desaminasa/genética , Adenosina Desaminasa/metabolismo , Adenosina Desaminasa/uso terapéutico
18.
Nat Mater ; 22(11): 1324-1331, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37770676

RESUMEN

Two-dimensional (2D) semiconductors, such as transition metal dichalcogenides, provide an opportunity for beyond-silicon exploration. However, the lab to fab transition of 2D semiconductors is still in its preliminary stages, and it has been challenging to meet manufacturing standards of stability and repeatability. Thus, there is a natural eagerness to grow wafer-level, high-quality films with industrially acceptable scale-cost-performance metrics. Here we report an improved chemical vapour deposition synthesis method in which the controlled release of precursors and substrates predeposited with amorphous Al2O3 ensure the uniform synthesis of monolayer MoS2 as large as 12 inches while also enabling fast and non-toxic growth to reduce manufacturing costs. Transistor arrays were fabricated to further confirm the high quality of the film and its integrated circuit application potential. This work achieves the co-optimization of scale-cost-performance metrics and lays the foundation for advancing the integration of 2D semiconductors in industry-standard pilot lines.

19.
Biomater Adv ; 153: 213575, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37557033

RESUMEN

Conventional implants tend to have significant limitations, as they are one-size-fits-all, require monitoring, and have the potential for immune rejection. However, 4D Printing presents a method to manufacture highly personalized, shape-changing, minimally invasive biomedical implants. Shape memory polymers (SMPs) with a glass transition temperature (Tg) between room and body temperature (20-38 °C) are particularly desirable for this purpose, as they can be deformed to a temporary shape before implantation, then undergo a shape change within the body. Commonly used SMPs possess either an undesirable Tg or lack the biocompatibility or mechanical properties necessary to match soft biological tissues. In this work, Poly(glycerol dodecanoate) acrylate (PGDA) with engineered pores is introduced to solve these issues. Pores are induced by porogen leaching, where microparticles are mixed with the printing ink and then are dissolved in water after 3D printing, creating a hierarchically porous texture to improve biological activity. With this method, highly complex shapes were printed, including overhanging structures, tilted structures, and a "3DBenchy". The porous SMP has a Tg of 35.6 °C and a Young's Modulus between 0.31 and 1.22 MPa, comparable to soft tissues. A one-way shape memory effect (SME) with shape fixity and recovery ratios exceeding 98 % was also demonstrated. Cultured cells had a survival rate exceeding 90 %, demonstrating cytocompatibility. This novel method creates hierarchically porous shape memory scaffolds with an optimal Tg for reducing the invasiveness of implantation and allows for precise control over elastic modulus, porosity, structure, and transition temperature.


Asunto(s)
Polímeros , Ingeniería de Tejidos , Porosidad , Prótesis e Implantes , Impresión Tridimensional
20.
ESC Heart Fail ; 10(6): 3311-3329, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641543

RESUMEN

AIMS: We aim to explore the role and mechanism of vagus nerve stimulation (VNS) in coronary endothelial cells and angiogenesis in infarcted hearts. METHODS AND RESULTS: Seven days after rat myocardial infarction (MI) was prepared by ligation of the left anterior descending coronary artery, the left cervical vagus nerve was treated with electrical stimulation 1 h after intraperitoneal administration of the α7-nicotinic acetylcholine inhibitor mecamylamine or the mAChR inhibitor atropine or 3 days after local injection of Ad-shSDF-1α into the infarcted heart. Cardiac tissue acetylcholine (ACh) and serum ACh, tumour necrosis factor α (TNF-α), interleukin 1ß (IL-1ß) and interleukin 6 (IL-6) levels were detected by ELISA to determine whether VNS was successful. An inflammatory injury model in human coronary artery endothelial cells (HCAECs) was established by lipopolysaccharide and identified by evaluating TNF-α, IL-1ß and IL-6 levels and tube formation. Immunohistochemistry staining was performed to evaluate CD31-positive vessel density and stromal cell-derived factor-l alpha (SDF-1α) expression in the MI heart in vivo and the expression and distribution of SDF-1α, C-X-C motif chemokine receptor 4 and CXCR7 in HCAECs in vitro. Western blotting was used to detect the levels of SDF-1α, V-akt murine thymoma viral oncogene homolog (AKT), phosphorylated AKT (pAKT), specificity protein 1 (Sp1) and phosphorylation of Sp1 in HCAECs. Left ventricular performance, including left ventricular systolic pressure, left ventricular end-diastolic pressure and rate of the rise and fall of ventricular pressure, should be evaluated 28 days after VNS treatment. VNS was successfully established for MI therapy with decreases in serum TNF-α, IL-1ß and IL-6 levels and increases in cardiac tissue and serum ACh levels, leading to increased SDF-1α expression in coronary endothelial cells of MI hearts, triggering angiogenesis of MI hearts with increased CD31-positive vessel density, which was abolished by the m/nAChR inhibitors mecamylamine and atropine or knockdown of SDF-1α by shRNA. ACh promoted SDF-1α expression and its distribution along with the branch of the formed tube in HCAECs, resulting in an increase in the number of tubes formed in HCAECs. ACh increased the levels of pAKT and phosphorylation of Sp1 in HCAECs, resulting in inducing SDF-1α expression, and the specific effects could be abolished by mecamylamine, atropine, the PI3K/AKT blocker wortmannin or the Sp1 blocker mithramycin. Functionally, VNS improved left ventricular performance, which could be abolished by Ad-shSDF-1α. CONCLUSIONS: VNS promoted angiogenesis to repair the infarcted heart by inducing SDF-1α expression and redistribution along new branches during angiogenesis, which was associated with the m/nAChR-AKT-Sp1 signalling pathway.


Asunto(s)
Infarto del Miocardio , Estimulación del Nervio Vago , Ratas , Humanos , Ratones , Animales , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas Sprague-Dawley , Acetilcolina , Células Endoteliales/metabolismo , Factor de Necrosis Tumoral alfa , Mecamilamina , Interleucina-6 , Fosfatidilinositol 3-Quinasas , Células del Estroma/metabolismo , Células del Estroma/patología , Derivados de Atropina
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