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1.
Cell Mol Life Sci ; 81(1): 60, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38279064

RESUMEN

Zebrafish have a remarkable ability to regenerate injured hearts. Altered hemodynamic forces after larval ventricle ablation activate the endocardial Klf2a-Notch signaling cascade to direct zebrafish cardiac regeneration. However, how the heart perceives blood flow changes and initiates signaling pathways promoting regeneration is not fully understood. The present study demonstrated that the mechanosensitive channel Trpv4 sensed the altered hemodynamic forces in injured hearts and its expression was regulated by blood flow. In addition to mediating the endocardial Klf2a-Notch signal cascade around the atrioventricular canal (AVC), we discovered that Trpv4 regulated nitric oxide (NO) signaling in the bulbus arteriosus (BA). Further experiments indicated that Notch signaling primarily acted at the early stage of regeneration, and the major role of NO signaling was at the late stage and through TGF-ß pathway. Overall, our findings revealed that mechanosensitive channels perceived the changes in hemodynamics after ventricle injury, and provide novel insights into the temporal and spatial coordination of multiple signaling pathways regulating heart regeneration.


Asunto(s)
Óxido Nítrico , Pez Cebra , Animales , Pez Cebra/metabolismo , Óxido Nítrico/metabolismo , Corazón , Endocardio/metabolismo , Hemodinámica , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(20): e2200678119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35549555

RESUMEN

SignificanceDynamic bonds have been found to enhance fracture toughness of hydrogels as sacrificial bonds, but the role of dynamic bonds to fatigue threshold of hydrogels is poorly understood because the wide dynamic range of viscoelastic response imposes a challenge on fatigue experiments. Here, by using polyampholyte hydrogels, we adopted a time-salt superposition principle to access a wide range of time scales that are otherwise difficult to access in fatigue tests. Relations between fatigue threshold and strain rate in elastic and viscoelastic regimes and the corresponding mechanism correlated to permanent/dynamic bonds were revealed. We believe that this work gives important insight into the design and development of fatigue-resistant soft materials composed of dynamic bonds.

3.
Proc Natl Acad Sci U S A ; 119(36): e2207422119, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36037384

RESUMEN

Understanding the physical principle that governs the stimuli-induced swelling and shrinking kinetics of hydrogels is indispensable for their applications. Here, we show that the shrinking and swelling kinetics of self-healing hydrogels could be intrinsically asymmetric. The structure frustration, formed by the large difference in the heat and solvent diffusions, remarkably slows down the shrinking kinetics. The plateau modulus of viscoelastic gels is found to be a key parameter governing the formation of structure frustration and, in turn, the asymmetric swelling and shrinking kinetics. This work provides fundamental understandings on the temperature-triggered transient structure formation in self-healing hydrogels. Our findings will find broad use in diverse applications of self-healing hydrogels, where cooperative diffusion of water and gel network is involved. Our findings should also give insight into the molecular diffusion in biological systems that possess macromolecular crowding environments similar to self-healing hydrogels.


Asunto(s)
Hidrogeles , Temperatura , Difusión , Hidrogeles/química , Cinética , Agua/química
4.
Macromol Rapid Commun ; 45(19): e2400327, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38837533

RESUMEN

Tough and self-healing hydrogels are typically sensitive to loading rates or temperatures due to the dynamic nature of noncovalent bonds. Understanding the structure evolution under varying loading conditions can provide valuable insights for developing new tough soft materials. In this study, polyampholyte (PA) hydrogel with a hierarchical structure is used as a model system. The evolution of the microscopic structure during loading is investigated under varied loading temperatures. By combining ultra-small angle X-ray scattering (USAXS) and Mooney-Rivlin analysis, it is elucidated that the deformation of bicontinuous hard/soft phase networks is closely correlated with the relaxation dynamics or strength of noncovalent bonds. At high loading temperatures, the gel is soft and ductile, and large affine deformation of the phase-separated networks is observed, correlated with the fast relaxation dynamics of noncovalent bonds. At low loading temperatures, the gel is stiff, and nonaffine deformation occurs from the onset of loading due to the substantial breaking of noncovalent bonds and limited chain mobility as well as weak adaptation of phase deformation to external stretch. This work provides an in-depth understanding of the relationship between structure and performance of tough and self-healing hydrogels.


Asunto(s)
Hidrogeles , Temperatura , Hidrogeles/química , Dispersión del Ángulo Pequeño , Difracción de Rayos X , Polímeros/química
5.
BMC Public Health ; 24(1): 2493, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39272064

RESUMEN

BACKGROUND: One of the challenges of physical training in extreme condition is frostbite, especially in Northeast China. In this study, we aimed to construct a risk prediction model for frostbite among soldiers in Northeast China, and verify its effect. METHODS: 698 participants were selected via convenience sampling from Northeast China from December 2021 to January 2022 (winter). They were randomly divided into a training set (N = 479) and a testing set (N = 202) in a ratio of 7:3. All participants completed a researcher-made questionnaire on frostbite. The prediction model was constructed through the use of Logistic regression analysis, which was used to predict the independent risk factors for frostbite formation and screen significant indicators. The model's performance was assessed using the receiver operating characteristic (ROC) curve and decision curve analysis (DCA) to evaluate the prediction efficiency and goodness of fit. RESULTS: The incidence of frostbite in the training set was 19.83% (95 people), all of which were first-degree frostbite. Among them, frostbite in multiple parts was the most common (58.95%), followed by singular body parts like hands (24.21%), ears (11.58%) and feet (5.26%). Single factor logistic regression analyses showed that ambient temperature, ambient wind speed, outdoor stationary time, stationary status, and history of frostbite are independent risk factors that affect the occurrence of frostbite. Furthermore, we constructed the frostbite risk prediction model for soldiers in the northeastern region of China. The area under the receiver operating characteristic curve (AUC) for the risk of frostbite in the training set and testing set was 0.816 (95% CI, 0.770 ~ 0.862) and 0.787 (95% CI, 0.713 ~ 0.860), respectively. The Hosmer-Lemeshow test of the model showed χ2 = 11.328 and P = 0.184 (> 0.05). The DCA curve indicated that most of the clinical net benefits of the model are greater than 0, demonstrating good clinical usefulness. CONCLUSION: The constructed frostbite prediction model can effectively identify soldiers with a higher risk of frostbite. It provided theoretical support for commanders to take preventive measures to reduce the incidence of frostbite among soldiers and was of great clinical guiding significance.


Asunto(s)
Congelación de Extremidades , Personal Militar , Humanos , China/epidemiología , Congelación de Extremidades/epidemiología , Personal Militar/estadística & datos numéricos , Masculino , Estudios Transversales , Medición de Riesgo , Adulto , Adulto Joven , Factores de Riesgo , Femenino , Curva ROC , Modelos Logísticos , Encuestas y Cuestionarios
6.
BMC Pediatr ; 24(1): 90, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38302958

RESUMEN

BACKGROUND: Tsutsugamushi, also known as bush typhus, is a naturally occurring disease caused by Orientia tsutsugamushi. We reported a case of vertical mother-to-newborn transmission of Orientia tsutsugamushi infection in a newborn from Yunnan (China). CASE PRESENTATION: Decreased fetal movements were observed at 39 weeks of gestation. After birth, the newborn (female) had recurrent fever, shortness of breath, and bruising around the mouth and extremities. At 5 h 58 min of age, the newborn was admitted for fever, shortness of breath and generalized rash. The liver was palpable 3 cm below the costal margin, and the limbs showed pitting edema. There was subcutaneous bleeding. Investigations suggested heavy infection, myocardial damage, decreased platelets. Treatment with cefotaxime and ampicillin failed. The mother was hospitalized at 29 weeks of gestation with a fever for 4 consecutive days, and an ulcerated crust was found in the popliteal fossa. Due to this pregnancy history, A diagnosis of Orientia tsutsugamushi infection was suspected in our index case and confirmed by macrogenomic testing and she was treated with vancomycin and meropenem, and later azithromycin for 1 week. The newborn was discharged in good general condition, gradually normalizing body temperature, and decreasing rash and jaundice. There were no abnormalities on subsequent blood macrogenomic tests for the baby. And one month later she showed good mental health, sleep, and food intake and no fever, rash, or jaundice. CONCLUSION: Determining the cause of symptoms is the key to treating diseases, especially the rare diseases that can be misdiagnosed. SUITABLE FOR PEOPLE WITH: Infectious Diseases; Neonatology; Obstetrics.


Asunto(s)
Exantema , Enfermedades del Recién Nacido , Ictericia , Tifus por Ácaros , Femenino , Humanos , Recién Nacido , China , Disnea , Fiebre/diagnóstico , Tifus por Ácaros/diagnóstico
7.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-33782118

RESUMEN

Tough soft materials usually show strain softening and inelastic deformation. Here, we study the molecular mechanism of abnormally large nonsoftening, quasi-linear but inelastic deformation in tough hydrogels made of hyperconnective physical network and linear polymers as molecular glues to the network. The interplay of hyperconnectivity of network and effective load transfer by molecular glues prevents stress concentration, which is revealed by an affine deformation of the network to the bulk deformation up to sample failure. The suppression of local stress concentration and strain amplification plays a key role in avoiding necking or strain softening and endows the gels with a unique large nonsoftening, quasi-linear but inelastic deformation.

8.
Biol Reprod ; 109(6): 938-953, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37676254

RESUMEN

A large proportion of miscarriages are classified as unexplained miscarriages since no cause is identified. No reliable biomarkers or treatments are available for these pregnancy losses. While our transcriptomic sequencing has revealed substantial upregulation of miR-146b-5p in unexplained miscarriage villous tissues, its role and associated molecular processes have yet to be fully characterized. Our work revealed that relative to samples from normal pregnancy, miR-146b-5p was significantly elevated in villous tissues from unexplained miscarriage patients and displayed promising diagnostic potential. Moreover, miR-146b-5p agomir contributed to higher rates of embryonic resorption in ICR mice. When overexpressed in HTR-8/SVneo cells, miR-146b-5p attenuated the proliferative, invasive, and migratory activity of these cells while suppressing the expression of MMP9 and immune inflammation-associated cytokines, including IL1B, IL11, CXCL1, CXCL8, and CXCL12. Conversely, inhibition of its expression enhanced proliferation, migration, and invasion abilities. Mechanistically, IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19 were identified as miR-146b-5p targets regulating trophoblast function, and silencing IL-1 receptor-associated kinase-1 had similar effects as miR-146b-5p overexpression, while IL-1 receptor-associated kinase-1 overexpression could partially reverse the inhibitory impact of this microRNA on trophoblasts. miR-146b-5p may inhibit trophoblast proliferation, migration, invasion, and implantation-associated inflammation by downregulating IL-1 receptor-associated kinase-1 and a disintegrin and metalloproteinase 19, participating in the pathogenesis of miscarriage and providing a critical biomarker and a promising therapeutic target for unexplained miscarriage.


Asunto(s)
Aborto Espontáneo , MicroARNs , Ratones , Animales , Embarazo , Femenino , Humanos , Aborto Espontáneo/genética , Quinasas Asociadas a Receptores de Interleucina-1/genética , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/farmacología , Desintegrinas/metabolismo , Desintegrinas/farmacología , Ratones Endogámicos ICR , MicroARNs/genética , MicroARNs/metabolismo , Trofoblastos/metabolismo , Inflamación/metabolismo , Proliferación Celular/fisiología , Metaloproteasas/metabolismo , Movimiento Celular , Proteínas ADAM/metabolismo
9.
Proc Natl Acad Sci U S A ; 117(32): 18962-18968, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32719128

RESUMEN

The memory of our brain, stored in soft matter, is dynamic, and it forgets spontaneously to filter unimportant information. By contrast, the existing manmade memory, made from hard materials, is static, and it does not forget without external stimuli. Here we propose a principle for developing dynamic memory from soft hydrogels with temperature-sensitive dynamic bonds. The memorizing-forgetting behavior is achieved based on fast water uptake and slow water release upon thermal stimulus, as well as thermal-history-dependent transparency change of these gels. The forgetting time is proportional to the thermal learning time, in analogy to the behavior of brain. The memory is stable against temperature fluctuation and large stretching; moreover, the forgetting process is programmable. This principle may inspire future research on dynamic memory based on the nonequilibrium process of soft matter.

10.
Proc Natl Acad Sci U S A ; 117(14): 7606-7612, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32209673

RESUMEN

Load-bearing biological tissues, such as muscles, are highly fatigue-resistant, but how the exquisite hierarchical structures of biological tissues contribute to their excellent fatigue resistance is not well understood. In this work, we study antifatigue properties of soft materials with hierarchical structures using polyampholyte hydrogels (PA gels) as a simple model system. PA gels are tough and self-healing, consisting of reversible ionic bonds at the 1-nm scale, a cross-linked polymer network at the 10-nm scale, and bicontinuous hard/soft phase networks at the 100-nm scale. We find that the polymer network at the 10-nm scale determines the threshold of energy release rate G0 above which the crack grows, while the bicontinuous phase networks at the 100-nm scale significantly decelerate the crack advance until a transition Gtran far above G0 In situ small-angle X-ray scattering analysis reveals that the hard phase network suppresses the crack advance to show decelerated fatigue fracture, and Gtran corresponds to the rupture of the hard phase network.

11.
Int J Urol ; 30(2): 155-160, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36349911

RESUMEN

OBJECTIVES: There is substantial concern about traditional transperitoneal laparoscopic radical cystectomy (TLRC) due to multiple postoperative complications. In contrast, extraperitoneal laparoscopic radical cystectomy (ELRC) appears to cause a lower rate of morbidity. The present study aimed to compare the efficacy of ELRC and TLRC for bladder cancer (BCa). METHODS: The clinical data of patients undergoing laparoscopic radical cystectomy for BCa from April 2018 to October 2021 were retrospectively analyzed, as ELRC and TLRC groups. The postoperative follow-up data of 275 patients were collected and the incidence of postoperative complications and other perioperative outcomes were compared between the two groups. RESULTS: Surgery was successfully completed in all patients without conversion to open surgery. There was no significant difference in the duration of cystectomy surgery (67.32 ± 23.53 vs 72.17 ± 25.72 min, p = 0.106), intraoperative blood loss (178.06 ± 110.4 vs. 174.56 ± 127.40 ml, p = 0.413), or the number of lymph node dissection (15.1 ± 5.7 vs. 14.5 ± 5.1, p = 0.380) between the two groups. The length of stay (11.6 ± 3.8 vs 14.7 ± 5.6 d, p < 0.001), time to resume food intake after surgery (2.3 ± 0.9 vs 3.0 ± 1.3 d, p < 0.001), and the incidence of ileus (p < 0.001) in the ELRC group were significantly lower than in the TLRC group. CONCLUSIONS: ELRC is a safe procedure that can reduce the incidence of postoperative complications, shorten postoperative hospital stay, reduce the duration of recovery of patients, and, therefore, should be promoted.


Asunto(s)
Laparoscopía , Neoplasias de la Vejiga Urinaria , Derivación Urinaria , Humanos , Cistectomía/efectos adversos , Cistectomía/métodos , Derivación Urinaria/métodos , Estudios Retrospectivos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/cirugía , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
12.
Molecules ; 28(11)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37298873

RESUMEN

Regulating redox homeostasis in tumor cells and exploiting oxidative stress to damage tumors is an efficacious strategy for cancer therapy. However, the strengths of organic nanomaterials within this strategy are often ignored. In this work, a light-triggered reactive oxygen species (ROS) damaging nanoamplifier (IrP-T) was developed for enhanced photodynamic therapy (PDT). The IrP-T was fabricated with an amphiphilic iridium complex and a MTH1 inhibitor (TH287). Under green light stimulation, IrP-T catalyzed the oxygen in cells to generate ROS for realizing oxidative damage; meanwhile, TH287 increased the accumulation of 8-oxo-dGTP, further strengthening oxidative stress and inducing cell death. IrP-T could maximize the use of a small amount of oxygen, thus further boosting the efficacy of PDT in hypoxic tumors. The construction of nanocapsules provided a valuable therapeutic strategy for oxidative damage and synergizing PDT.


Asunto(s)
Nanocápsulas , Neoplasias , Fotoquimioterapia , Humanos , Oxígeno/farmacología , Especies Reactivas de Oxígeno/metabolismo , Iridio/farmacología , Estrés Oxidativo , Neoplasias/tratamiento farmacológico , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología
13.
Reprod Biol Endocrinol ; 20(1): 82, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35610725

RESUMEN

BACKGROUND: Spontaneous abortions (SA) is amongst the most common complications associated with pregnancy in humans, and the underlying causes cannot be identified in roughly half of SA cases. We found miR-135a-5p to be significantly upregulated in SA-associated villus tissues, yet the function it plays in this context has yet to be clarified. This study explored the function of miR-135a-5p and its potential as a biomarker for unexplained SA. METHOD: RT-qPCR was employed for appraising miR-135a-5p expression within villus tissues with its clinical diagnostic values being assessed using ROC curves. The effects of miR-135a-5p in HTR-8/SVneo cells were analyzed via wound healing, Transwell, flow cytometry, EdU, CCK-8, and tube formation assays. Moreover, protein expression was examined via Western blotting, and interactions between miR-135a-5p and PTPN1 were explored through RIP-PCR, bioinformatics analyses and luciferase reporter assays. RESULTS: Relative to normal pregnancy (NP), villus tissue samples from pregnancies that ended in unexplained sporadic miscarriage (USM) or unexplained recurrent SA (URSA) exhibited miR-135a-5p upregulation. When this miRNA was overexpressed in HTR-8/SVneo cells, their migration, proliferation, and cell cycle progression were suppressed, as were their tube forming and invasive activities. miR-135a-5p over-expression also downregulated the protein level of cyclins, PTPN1, MMP2 and MMP9. In RIP-PCR assays, the Ago2 protein exhibited significant miR-135a-5p and PTPN1 mRNA enrichment, and dual-luciferase reporter assays indicated PTPN1 to be a bona fide miR-135a-5p target gene within HTR-8/SVneo cells. CONCLUSION: miR-135a-5p may suppress trophoblast migratory, invasive, proliferative, and angiogenic activity via targeting PTPN1, and it may thus offer value as a biomarker for unexplained SA.


Asunto(s)
Aborto Habitual , MicroARNs , Trofoblastos , Aborto Habitual/genética , Aborto Habitual/metabolismo , Biomarcadores/metabolismo , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Embarazo , Trofoblastos/citología , Trofoblastos/metabolismo
14.
Fish Shellfish Immunol ; 128: 228-237, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35940536

RESUMEN

2,2,4,4-tetra-brominated diphenyl ether (PBDE-47)-the dominant homologue of polybrominated diphenyl ethers-is a toxic environmental pollutant in the aquatic environment that continuously exists and bioaccumulates in the aquatic food chain. In experimental disease models, melatonin (MEL) has been reported to attenuate necroptosis and inflammatory responses. To further explore the mechanism underlying PBDE-47 toxicity and the mitigative impact of MEL detoxification, in this study, fish kidney cell models of PBDE-47 poisoning and/or MEL treatment were developed. The Ctenopharyngodon idellus kidney (CIK) cell line was treated with PBDE-47 (100 µM) and/or MEL (60 µM) for 24 h. Experimental data suggest that PBDE-47 exposure resulted in the enhancement of cytoplasmic Ca2+ concentration, induction of calcium dysmetabolism, decrease in the miR-140-5p miRNA level, upregulation of Toll-like Receptor 4 (TLR4) and nuclear factor-kappaB (NF-κB), triggering of receptor interacting serine/threonine kinase-induced necroptosis, and NF-κB pathway mediated secretion of inflammatory factors in CIK cells. PBDE-47-induced CIK cell damage could be mitigated by MEL through the regulation of calcium channels and the restoration of disorders of the miR-140-5p/TLR4/NF-κB axis. Overall, MEL relieved PBDE-47-induced necroptosis and the secretion of inflammatory factors through the miR-140-5p/TLR4/NF-κB axis. These findings enrich the current understanding of the toxicological molecular mechanisms of the PBDE-47 as well as the detoxification mechanisms of the MEL.


Asunto(s)
Contaminantes Ambientales , Melatonina , MicroARNs , Bifenilos Polibrominados , Animales , Calcio/metabolismo , Canales de Calcio , Éter , Éteres Difenilos Halogenados/toxicidad , Riñón/metabolismo , Melatonina/farmacología , MicroARNs/genética , MicroARNs/metabolismo , FN-kappa B/metabolismo , Necroptosis , Bifenilos Polibrominados/toxicidad , Proteínas Serina-Treonina Quinasas , Serina , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
15.
World J Surg Oncol ; 20(1): 174, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35650630

RESUMEN

BACKGROUND: Mammalian LEM-domain proteins (LEMs) are encoded by seven genes, including LAP2, EMD, LEMD1, LEMD2, LEMD3, ANKLE1, and ANKLE2. Though some LEMs were involved in various tumor progression, the expression and prognostic values of LEMs in prostate adenocarcinoma (PRAD) have yet to be analyzed. METHODS: Herein, we investigated the expression, survival data, and immune infiltration levels of LEMs in PRAD patients from ATCG, TIMER, LinkedOmics, and TISIDB databases. We also further validated the mRNA and protein expression levels of ANKLE1, EMD, and LEMD2 in human prostate tumor specimens by qPCR, WB, and IHC. RESULTS: We found that all LEM expressions, except for that of LAP2, were markedly altered in PRAD compared to the normal samples. Among all LEMs, only the expressions of ANKLE1, EMD, and LEMD2 were correlated with advanced tumor stage and survival prognosis in PRAD. Consistent with the predicted computational results, the mRNA and protein expression levels of these genes were markedly increased in the PRAD group. We then found that ANKLE1, EMD, and LEMD2 expressions were markedly correlated with immune cell infiltration levels. High ANKLE1, EMD, and LEMD2 expressions predicted a worse prognosis in PRAD based on immune cells. DNA methylation or/and copy number variations may contribute to the abnormal upregulation of ANKLE1, EMD, and LEMD2 in PRAD. CONCLUSIONS: Taken together, this study implied that ANKLE1, EMD, and LEMD2 were promising prognosis predictors and potential immunotherapy targets for PRAD patients.


Asunto(s)
Variaciones en el Número de Copia de ADN , Neoplasias de la Próstata , Endonucleasas/genética , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas Nucleares/genética , Pronóstico , Próstata/patología , Neoplasias de la Próstata/patología , ARN Mensajero/genética
16.
J Gen Virol ; 102(3)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33507144

RESUMEN

The zebrafish (Danio rerio) possesses evolutionarily conserved innate and adaptive immunity as a mammal and has recently become a popular vertebrate model to exploit infection and immunity. Antiviral RNA interference (RNAi) has been illuminated in various model organisms, including Arabidopsis thaliana, Drosophila melanogaster, Caenorhabditis elegans and mice. However, to date, there is no report on the antiviral RNAi pathway of zebrafish. Here, we have evaluated the possible use of zebrafish to study antiviral RNAi with Sindbis virus (SINV), vesicular stomatitis virus (VSV) and Nodamura virus (NoV). We find that SINVs and NoVs induce the production of virus-derived small interfering RNAs (vsiRNAs), the hallmark of antiviral RNAi, with a preference for a length of 22 nucleotides, after infection of larval zebrafish. Meanwhile, the suppressor of RNAi (VSR) protein, NoV B2, may affect the accumulation of the NoV in zebrafish. Furthermore, taking advantage of the fact that zebrafish argonaute-2 (Ago2) protein is naturally deficient in cleavage compared with that of mammals, we provide evidence that the slicing activity of human Ago2 can virtually inhibit the accumulation of RNA virus after being ectopically expressed in larval zebrafish. Thus, zebrafish may be a unique model organism to study the antiviral RNAi pathway.


Asunto(s)
Interferencia de ARN , Infecciones por Virus ARN/virología , Virus ARN/fisiología , ARN Interferente Pequeño/metabolismo , ARN Viral/metabolismo , Pez Cebra/virología , Animales , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Inmunidad Innata , Modelos Animales , Nodaviridae/inmunología , Nodaviridae/fisiología , Infecciones por Virus ARN/inmunología , Virus ARN/inmunología , Virus Sindbis/inmunología , Virus Sindbis/fisiología , Vesiculovirus/inmunología , Vesiculovirus/fisiología , Pez Cebra/genética , Pez Cebra/inmunología , Proteínas de Pez Cebra/metabolismo
17.
Int J Mol Sci ; 22(8)2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33920448

RESUMEN

Cardiac regenerative capacity varies widely among vertebrates. Zebrafish can robustly regenerate injured hearts and are excellent models to study the mechanisms of heart regeneration. Recent studies have shown that enhancers are able to respond to injury and regulate the regeneration process. However, the mechanisms to activate these regeneration-responsive enhancers (RREs) remain poorly understood. Here, we utilized transient and transgenic analysis combined with a larval zebrafish ventricle ablation model to explore the activation and regulation of a representative RRE. lepb-linked enhancer sequence (LEN) directed enhanced green fluorescent protein (EGFP) expression in response to larval ventricle regeneration and such activation was attenuated by hemodynamic force alteration and mechanosensation pathway modulation. Further analysis revealed that Notch signaling influenced the endocardial LEN activity as well as endogenous lepb expression. Altogether, our work has established zebrafish models for rapid characterization of cardiac RREs in vivo and provides novel insights on the regulation of LEN by hemodynamic forces and other signaling pathways during heart regeneration.


Asunto(s)
Ventrículos Cardíacos/metabolismo , Hemodinámica , Miocardio/metabolismo , Regeneración , Función Ventricular , Pez Cebra/metabolismo , Animales , Pez Cebra/genética
18.
Biogerontology ; 21(5): 637-652, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32372324

RESUMEN

Aging dramatically increases the risk of cardiovascular diseases in human. Animal models are of great value to study cardiac aging, and zebrafish have become a popular model for aging study recently. However, there is limited knowledge about the progression and regulation of cardiac aging in zebrafish. In this study we first validated the effectiveness of a panel of aging-related markers and revealed their spatial-temporal specificity. Using these markers, we discovered that cardiac aging in zebrafish initiated at mid-age around 24 months, followed by a gradual progression marked with increased DNA damage, inflammatory response and reduced mitochondrial function. Furthermore, we showed aging-related expression profile change in zebrafish hearts was similar to that in rat hearts. Overall, our results provide a deeper insight into the cardiac aging process in zebrafish, which will set up foundation for generating novel cardiac aging models suitable for large scale screening of pharmaceutical targets.


Asunto(s)
Envejecimiento , Corazón/fisiología , Transcriptoma , Pez Cebra , Animales , Daño del ADN , Inflamación , Mitocondrias Cardíacas , Modelos Animales , Pez Cebra/genética
19.
Proc Natl Acad Sci U S A ; 114(4): 687-692, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-28069943

RESUMEN

Tyrosyl-tRNA synthetase (TyrRS) is well known for its essential aminoacylation function in protein synthesis. Recently, TyrRS has been shown to translocate to the nucleus and protect against DNA damage due to oxidative stress. However, the mechanism of TyrRS nuclear localization has not yet been determined. Herein, we report that TyrRS becomes highly acetylated in response to oxidative stress, which promotes nuclear translocation. Moreover, p300/CBP-associated factor (PCAF), an acetyltransferase, and sirtuin 1 (SIRT1), a NAD+-dependent deacetylase, regulate the nuclear localization of TyrRS in an acetylation-dependent manner. Oxidative stress increases the level of PCAF and decreases the level of SIRT1 and deacetylase activity, all of which promote the nuclear translocation of hyperacetylated TyrRS. Furthermore, TyrRS is primarily acetylated on the K244 residue near the nuclear localization signal (NLS), and acetylation inhibits the aminoacylation activity of TyrRS. Molecular dynamics simulations have shown that the in silico acetylation of K244 induces conformational changes in TyrRS near the NLS, which may promote the nuclear translocation of acetylated TyrRS. Herein, we show that the acetylated K244 residue of TyrRS protects against DNA damage in mammalian cells and zebrafish by activating DNA repair genes downstream of transcription factor E2F1. Our study reveals a previously unknown mechanism by which acetylation regulates an aminoacyl-tRNA synthetase, thus affecting the repair pathways for damaged DNA.


Asunto(s)
Núcleo Celular/metabolismo , Daño del ADN/fisiología , Estrés Oxidativo/fisiología , Tirosina-ARNt Ligasa/metabolismo , Acetilación , Animales , Línea Celular , Línea Celular Tumoral , Factor de Transcripción E2F1/metabolismo , Células HEK293 , Células HeLa , Humanos , Transporte de Proteínas/fisiología , Transducción de Señal/fisiología , Sirtuina 1/metabolismo , Pez Cebra , Factores de Transcripción p300-CBP/metabolismo
20.
J Cell Biochem ; 120(6): 10697-10706, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30652346

RESUMEN

Osteosarcoma (OS) is a malignant neoplasia in bone, characterized with main occurrence in teenagers. Calycosin (CC), a bioactive compound, is found to play potent pharmacological effects against cancer. Our previous study indicates CC-exerted benefits for anti-OS effect. However, further molecular mechanism behind this action needs to be investigated. In this study, human OS samples and clinical data were collected and used for further test and analysis. In addition, human osteosarcoma cell line (143B) and tumor-xenograft nude mice were used to evaluate antineoplastic activities of CC through a series of biochemical methods and immunoassays, respectively. Compared with non-OS controls, human OS samples showed increased levels of neoplastic microRNA-223 (miR-223), and elevated expressions of NF-κBp65, IκBα proteins in tumor cells. In cell culture study, CC-treated 143B cells showed reduced cell growth, increased lactic dehydrogenase (LD) content, and downregulated cellular miR-223 level. Immunolabeled cells of proliferating cell nuclear antigen, B-cell lymphoma 2 (Bcl-2), poly(ADP-ribose) polymerase (PARP) in CC treatments were decreased dose-dependently, while caspase-3 positive cells were elevated. Further, protein expressions of NF-κBp65, IκBα in CC-treated cells were downregulated. In addition, tumor-xenograft nude mice followed by CC treatments exhibited reductions of tumor mass, miR-223 levels, and Bcl-2, PARP-positive cells, as well as downregulations of NF-κBp65, IκBα protein expressions in OS samples. Taken together, these experimental findings reveal that CC exhibits potential pharmacological activities against OS through inducing apoptosis and inhibiting miR-223-IκBα signaling pathway in neoplastic cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Regulación Neoplásica de la Expresión Génica , Isoflavonas/farmacología , MicroARNs/genética , Osteosarcoma/tratamiento farmacológico , Factor de Transcripción ReIA/genética , Adolescente , Animales , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Neoplasias Óseas/cirugía , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Niño , Femenino , Humanos , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Masculino , Ratones , Ratones Desnudos , MicroARNs/metabolismo , Inhibidor NF-kappaB alfa/genética , Inhibidor NF-kappaB alfa/metabolismo , Osteosarcoma/genética , Osteosarcoma/patología , Osteosarcoma/cirugía , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal , Factor de Transcripción ReIA/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
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