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1.
Am J Pathol ; 194(8): 1571-1580, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38762116

RESUMEN

Duchenne muscular dystrophy (DMD), caused by loss-of-function mutations in the dystrophin gene, results in progressive muscle weakness and early fatality. Impaired autophagy is one of the cellular hallmarks of DMD, contributing to the disease progression. Molecular mechanisms underlying the inhibition of autophagy in DMD are not well understood. In the current study, the DMD mouse model mdx was used for the investigation of signaling pathways leading to suppression of autophagy. Mammalian target of rapamycin complex 1 (mTORC1) was hyperactive in the DMD muscles, accompanying muscle weakness and autophagy impairment. Surprisingly, Akt, a well-known upstream regulator of mTORC1, was not responsible for mTORC1 activation or the dystrophic muscle phenotypes. Instead, leucyl-tRNA synthetase (LeuRS) was overexpressed in mdx muscles compared with the wild type. LeuRS activates mTORC1 in a noncanonical mechanism that involves interaction with RagD, an activator of mTORC1. Disrupting LeuRS interaction with RagD by the small-molecule inhibitor BC-LI-0186 reduced mTORC1 activity, restored autophagy, and ameliorated myofiber damage in the mdx muscles. Furthermore, inhibition of LeuRS by BC-LI-0186 improved dystrophic muscle strength in an autophagy-dependent manner. Taken together, our findings uncovered a noncanonical function of the housekeeping protein LeuRS as a potential therapeutic target in the treatment of DMD.


Asunto(s)
Autofagia , Modelos Animales de Enfermedad , Leucina-ARNt Ligasa , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones Endogámicos mdx , Debilidad Muscular , Distrofia Muscular de Duchenne , Animales , Masculino , Ratones , Leucina-ARNt Ligasa/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones Endogámicos C57BL , Debilidad Muscular/metabolismo , Debilidad Muscular/patología , Músculo Esquelético/patología , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/patología , Distrofia Muscular de Duchenne/metabolismo , Transducción de Señal
2.
Small ; 20(33): e2400849, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38644168

RESUMEN

Liquid organic hydrogen carrier is a promising option for the transport and storage of hydrogen as a clean energy source. This study examines the stability and behavior of organic drops immobilized on a substrate during an interfacial hydrogen-evolution reaction (HER) at the drop surface and its surrounding aqueous solution. Hydrogen microbubbles form within the drop and rise to the drop apex. The growth rate of the hydrogen in-drop bubble increases with the concentration of the reactant in the surrounding medium. The drop remains stable till the buoyancy acting on the in-drop bubble is large enough to overcome the capillary force and the external viscous drag. The bubble spontaneously rises and carries a portion drop liquid to the solution surface. These spontaneous rising in-drop bubbles are detected in measurements using a high-precision sensor placed on the upper surface of the aqueous solution, reversing the settling phase from phase separation in the reactive emulsion. The finding from this work provides new insights into the behaviors of drops and bubbles in many interfacial gas evolution reactions in clean technologies.

3.
Environ Sci Technol ; 58(35): 15619-15628, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38272008

RESUMEN

Surface-enhanced Raman spectroscopy (SERS) has been well explored as a highly effective characterization technique that is capable of chemical pollutant detection and identification at very low concentrations. Machine learning has been previously used to identify compounds based on SERS spectral data. However, utilization of SERS to quantify concentrations, with or without machine learning, has been difficult due to the spectral intensity being sensitive to confounding factors such as the substrate parameters, orientation of the analyte, and sample preparation technique. Here, we demonstrate an approach for predicting the concentration of sample pollutants from SERS spectra using machine learning. Frequency domain transform methods, including the Fourier and Walsh-Hadamard transforms, are applied to spectral data sets of three analytes (rhodamine 6G, chlorpyrifos, and triclosan), which are then used to train machine learning algorithms. Using standard machine learning models, the concentration of the sample pollutants is predicted with >80% cross-validation accuracy from raw SERS data. A cross-validation accuracy of 85% was achieved using deep learning for a moderately sized data set (∼100 spectra), and 70-80% was achieved for small data sets (∼50 spectra). Performance can be maintained within this range even when combining various sample preparation techniques and environmental media interference. Additionally, as a spectral pretreatment, the Fourier and Hadamard transforms are shown to consistently improve prediction accuracy across multiple data sets. Finally, standard models were shown to accurately identify characteristic peaks of compounds via analysis of their importance scores, further verifying their predictive value.


Asunto(s)
Aprendizaje Automático , Espectrometría Raman , Algoritmos
4.
Analyst ; 148(16): 3748-3757, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37439271

RESUMEN

Clinical semen quality assessment is critical to the treatment of infertility. Sperm DNA integrity testing provides critical information that can steer treatment and influence outcomes and offspring health. Flow cytometry is the gold standard approach to assess DNA integrity, but it is not commonly applied at the clinical level. The sperm chromatin dispersion (SCD) assay provides a simpler and cheaper alternative. However, SCD is low-throughput and non-quantitative - sperm assessment is serial, manual and suffers inter- and intra-observer variations. Here, an automated SCD analysis method is presented that enables quantitative sperm DNA quality assessment at the single-cell and population levels. Levering automated optical microscopy and a chromatin diffusion-based analysis, a sample of thousands of sperm that would otherwise require 5 hours is assessed in under 10 minutes - a clinically viable workflow. The sperm DNA diffusion coefficient (DDNA) measurement correlates (R2 = 0.96) with DNA fragmentation index (DFI) from the cytometry-based sperm chromatin structure assay (SCSA). The automated measurement of population-level sperm DNA fragmentation (% sDF) prevents inter-observer variations and shows a good agreement with the SCSA % DFI (R2 = 0.98). This automated approach standardizes and accelerates SCD-based sperm DNA analysis, enabling the clinical application of sperm DNA integrity assessment.


Asunto(s)
Análisis de Semen , Semen , Masculino , Humanos , Análisis de Semen/métodos , Espermatozoides , ADN/genética , ADN/análisis , Cromatina/genética , Fragmentación del ADN
5.
Ophthalmic Res ; 66(1): 1020-1029, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37245507

RESUMEN

BACKGROUND: The iStent (Glaukos Corporation; Laguna Hills, CA, USA) is one of the minimally invasive glaucoma devices. It can be inserted at the time of phacoemulsification or as a stand-alone procedure to lower the intraocular pressure (IOP). OBJECTIVE: Our aim was to conduct a systematic review and meta-analysis comparing the effect of iStent insertion at the time of phacoemulsification with phacoemulsification alone in patients with ocular hypertension or open-angle glaucoma. METHODS: We searched EMBASE, MEDLINE (OVID and PubMed), CINAHL, and Cochrane Library for articles published between 2008 and June 2022 (PRISMA 2020 for the checklist). Studies comparing the IOP-lowering effect of iStent with phacoemulsification versus phacoemulsification alone were included. The endpoints were IOP reduction (IOPR) and the mean reduction in the number of glaucoma drops. A quality-effects model was used to compare both surgical groups. RESULTS: Ten studies were included, reporting on 1,453 eyes. Eight hundred fifty three eyes had the combined iStent and phacoemulsification, and 600 eyes underwent phacoemulsification alone. IOPR was higher in the combined surgery at of 4.7 ± 2 mm Hg compared to 2.8 ± 1.9 mm Hg in phacoemulsification alone. A greater decrease in postoperative eye drops was noted in the combined group having a decrease of 1.2 ± 0.3 eye drops versus of 0.6 ± 0.6 drops in isolated phacoemulsification. The quality effect model showed an IOPR weighted mean difference (WMD) of 1.22 mm Hg (confidence interval [CI]: [-0.43, 2.87]; Q = 315.64; p < 0.01; I2 = 97%) and decreased eye drops WMD 0.42 drops (CI: [0.22, 0.62]; Q = 42.6; p < 0.01; I2 = 84%) between both surgical groups. Subgroup analysis shows that the new generation iStent may be more effective in reducing IOP. CONCLUSION: iStent has a synergetic effect with phacoemulsification. The reduction of IOP and glaucoma eye drops was higher when iStent is combined with phacoemulsification compared with isolated phacoemulsification.


Asunto(s)
Implantes de Drenaje de Glaucoma , Glaucoma de Ángulo Abierto , Glaucoma , Facoemulsificación , Humanos , Facoemulsificación/métodos , Glaucoma de Ángulo Abierto/complicaciones , Glaucoma de Ángulo Abierto/cirugía , Glaucoma/cirugía , Presión Intraocular , Malla Trabecular/cirugía , Soluciones Oftálmicas
6.
BMC Oral Health ; 23(1): 821, 2023 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-37899448

RESUMEN

BACKGROUND: This randomized controlled clinical trial compared the effects of platelet-rich fibrin (PRF) and concentrated growth factor (CGF) on early bone healing after endodontic microsurgery. METHODS: Eighteen patients with an isolated periapical lesion < 10 mm in the maxillary anterior region were randomly assigned to three groups: control, PRF, or CGF. Endodontic microsurgery was performed and PRF or CGF membranes were placed over the bone defects in the experimental groups. The volume of the bone defect at postoperative one week, three months, and six months was evaluated using cone-beam computed tomography and Mimics software. The results were statistically analyzed using the Kruskal-Wallis test and post-hoc Mann-Whitney U test with Bonferroni correction. RESULTS: At the three-month follow-up, the PRF and CGF groups showed significantly greater bone healing compared with the control group (p > 0.05). However, no significant difference was observed between the PRF and CGF groups. At the six-month follow-up, no significant differences were observed between the groups. CONCLUSIONS: These results suggested that PRF and CGF promote early bone healing after endodontic microsurgery.


Asunto(s)
Fibrina Rica en Plaquetas , Humanos , Fibrina Rica en Plaquetas/metabolismo , Microcirugia , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Tomografía Computarizada de Haz Cónico/métodos
7.
Medicina (Kaunas) ; 59(12)2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38138164

RESUMEN

Free gingival graft (FGG) is the gold standard procedure for the reliable augmentation of lost keratinized mucosa (KM) around dental implants. This conventional surgical approach has its drawbacks, including limitations in manipulation, the requirement for suturing, postoperative discomfort, and pain. This case report aimed to evaluate the efficacy of a simplified free gingival graft (sFGG) in addressing the issue of inadequate keratinized mucosa around dental implants. Fixation tacks were used to perform the sFGG procedure. Initially, a partial-thickness flap was created and apically repositioned. The gingival graft was harvested from the palate with a narrow profile and securely affixed to the recipient site using 5 mm long fixation tacks. Significant gains in keratinized mucosa were achieved and successfully maintained within 1 year. Consequently, the sFGG technique emerges as a simple and reliable treatment approach for managing inadequate keratinized mucosa around dental implants.


Asunto(s)
Implantes Dentales , Humanos , Encía/cirugía , Membrana Mucosa , Colgajos Quirúrgicos , Atención Odontológica
8.
J Cell Physiol ; 237(8): 3381-3393, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35696529

RESUMEN

Cytoplasmic serine/threonine Pim kinases have emerged as important modulators of immune regulation and oncology. However, their regulatory roles in bone remodeling remain obscure. Here, we aimed to determine the roles of Pim kinases in periodontal disease (PD), focusing on the regulation of osteoclastogenesis and bone resorptive activity. We investigated Pim kinases expression in PD by analyzing data from the online Gene Expression Omnibus database and using ligature-induced periodontitis mouse model. The expression of Pim kinases during receptor activator of nuclear factor kB ligand (RANKL)-induced osteoclastogenesis was assessed in mouse bone marrow-derived macrophages (BMMs) using reverse transcription polymerase chain reaction. Osteoclast differentiation and bone resorption activity were respectively verified by tartrate-resistant acid phosphatase staining and dentin disc-based bone resorption assays. We silenced and overexpressed Pim-2 using small interfering RNA (siRNA) and retroviral vector, respectively, to investigate the molecular mechanisms underlying Pim-2 regulation in RANKL-induced osteoclastogenesis and bone resorption activity. Upregulated expression of Pim-2 was observed in both patients with PD and periodontitis-affected mouse gingival tissues. siRNA-mediated silencing of Pim-2 in BMMs diminished RANKL-induced resorptive activity without affecting osteoclastogenesis. Moreover, RANKL-triggered stimulation of a3 isoform, which is a subunit of vacuolar-type ATPase, was selectively attenuated in BMMs on silencing Pim-2. The overexpression of Pim-2 with a retroviral vector stimulated the a3 subunit, thus inducing bone resorption activity. Taken together, these results suggest that Pim-2 acts as a major modulator of osteoclastic activity by regulating a3 isoform expression in PD.


Asunto(s)
Resorción Ósea , Enfermedades Periodontales , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas , ATPasas de Translocación de Protón Vacuolares , Animales , Resorción Ósea/genética , Resorción Ósea/metabolismo , Diferenciación Celular , Silenciador del Gen , Ratones , Osteoclastos/metabolismo , Enfermedades Periodontales/genética , Enfermedades Periodontales/metabolismo , Periodontitis/genética , Periodontitis/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Ligando RANK/metabolismo , ARN Interferente Pequeño/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo
9.
FASEB J ; 35(10): e21948, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34569098

RESUMEN

Aminoacyl-tRNA synthetases (aaRSs) are house-keeping enzymes that are essential for protein synthesis. However, it has become increasingly evident that some aaRSs also have non-translational functions. Here we report the identification of a non-translational function of threonyl-tRNA synthetase (ThrRS) in myogenic differentiation. We find that ThrRS negatively regulates myoblast differentiation in vitro and injury-induced skeletal muscle regeneration in vivo. This function is independent of amino acid binding or aminoacylation activity of ThrRS, and knockdown of ThrRS leads to enhanced differentiation without affecting the global protein synthesis rate. Furthermore, we show that the non-catalytic new domains (UNE-T and TGS) of ThrRS are both necessary and sufficient for the myogenic function. In searching for a molecular mechanism of this new function, we find the kinase JNK to be a downstream target of ThrRS. Our data further reveal MEKK4 and MKK4 as upstream regulators of JNK in myogenesis and the MEKK4-MKK4-JNK pathway to be a mediator of the myogenic function of ThrRS. Finally, we show that ThrRS physically interacts with Axin1, disrupts Axin1-MEKK4 interaction and consequently inhibits JNK signaling. In conclusion, we uncover a non-translational function for ThrRS in the maintenance of homeostasis of skeletal myogenesis and identify the Axin1-MEKK4-MKK4-JNK signaling axis to be an immediate target of ThrRS action.


Asunto(s)
Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas , Desarrollo de Músculos , Treonina-ARNt Ligasa/metabolismo , Animales , Proteína Axina/metabolismo , Femenino , MAP Quinasa Quinasa 4/metabolismo , MAP Quinasa Quinasa Quinasa 4/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Unión Proteica , Biosíntesis de Proteínas , Dominios Proteicos , Treonina-ARNt Ligasa/química
10.
Langmuir ; 38(37): 11227-11235, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36067516

RESUMEN

Liquid-liquid extraction based on surface nanodroplets can be a green and sustainable technique to extract and concentrate analytes from a sample flow. However, because of the extremely small volume of each droplet (<10 fL, tens of micrometers in base radius and a few or less than 1 µm in height), only a few in situ analytical techniques, such as surface-enhanced Raman spectroscopy, were applicable for the online detection and analysis based on nanodroplet extraction. To demonstrate the versatility of surface nanodroplet-based extraction, in this work, the formation of octanol surface nanodroplets and extraction were performed inside a 3 m Teflon capillary tube. After extraction, surface nanodroplets were collected by injecting air into the tube, by which the contact line of surface droplets was collected by the capillary force. As the capillary allows for the formation of ∼1012 surface nanodroplets on the capillary wall, ≥2 mL of octanol can be collected after extraction. The volume of the collected octanol was enough for the analysis of offline analytical techniques such as UV-vis, GC-MS, and others. Coupled with UV-vis, reliable extraction and detection of two common water pollutants, triclosan and chlorpyrifos, was shown by a linear relationship between the analyte concentration in the sample solution and UV-vis absorbance. Moreover, the limit of detection (LOD) as low as 2 × 10-9 M for triclosan (∼0.58 µg/L) and 3 × 10-9 M for chlorpyrifos (∼1.05 µg/L) could be achieved. The collected surface droplets were also analyzed via gas chromatography (GC) and fluorescence microscopy. Our work shows that surface nanodroplet extraction may potentially streamline the process in sample pretreatment for sensitive chemical detection and quantification by using common analytic tools.


Asunto(s)
Cloropirifos , Triclosán , Contaminantes Químicos del Agua , Contaminantes del Agua , Octanoles , Politetrafluoroetileno , Contaminantes del Agua/análisis , Contaminantes Químicos del Agua/análisis
11.
Molecules ; 27(15)2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-35956750

RESUMEN

7α,25-dihydroxycholesterol (7α,25-DHC) is an oxysterol synthesized from 25-hydroxycholesterol by cytochrome P450 family 7 subfamily B member 1 (CYP7B1) and is a monooxygenase (oxysterol-7α-hydroxylase) expressed under inflammatory conditions in various cell types. In this study, we verified that 7α,25-DHC-induced oxiapoptophagy is mediated by apoptosis, oxidative stress, and autophagy in L929 mouse fibroblasts. MTT assays and live/dead cell staining revealed that cytotoxicity was increased by 7α,25-DHC in L929 cells. Consequentially, cells with condensed chromatin and altered morphology were enhanced in L929 cells incubated with 7α,25-DHC for 48 h. Furthermore, apoptotic population was increased by 7α,25-DHC exposure through the cascade activation of caspase-9, caspase-3, and poly (ADP-ribose) polymerase in the intrinsic pathway of apoptosis in these cells. 7α,25-DHC upregulated reactive oxygen species (ROS) in L929 cells. Expression of autophagy biomarkers, including beclin-1 and LC3, was significantly increased by 7α,25-DHC treatment in L929 cells. 7α,25-DHC inhibits the phosphorylation of Akt associated with autophagy and increases p53 expression in L929 cells. In addition, inhibition of G-protein-coupled receptor 183 (GPR183), a receptor of 7α,25-DHC, using GPR183 specific antagonist NIBR189 suppressed 7α,25-DHC-induced apoptosis, ROS production, and autophagy in L929 cells. Collectively, GPR183 regulates 7α,25-DHC-induced oxiapoptophagy in L929 cells.


Asunto(s)
Oxiesteroles , Receptores Acoplados a Proteínas G , Animales , Apoptosis/genética , Apoptosis/fisiología , Autofagia/genética , Autofagia/fisiología , Fibroblastos/metabolismo , Hidroxicolesteroles/metabolismo , Ratones , Oxiesteroles/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
12.
Langmuir ; 37(17): 5290-5298, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33891427

RESUMEN

In this work, we investigate the crystallization of droplets formed on micropatterned surfaces. By solvent exchange in a microchamber, a ternary solution consisting of a model compound ß-alanine, water, and isopropanol was displaced by a flow of isopropanol. In the process, oiling-out droplets formed and crystallized. Our results showed that the shape and size of the crystals on surfaces with chemical micropatterns could be simply mediated by the flow conditions of solvent exchange. More uniform crystals formed on hydrophilic microdomains compared to hydrophobic microdomains or homogeneous surfaces. Varying flow rates or channel heights led to the formation of thin films with microholes, connected networks of crystals, or small diamond-shaped crystals. Physical microstructures (represented by microlenses) on the surface allowed the easy detachment of crystals from the surface. Beyond oiling-out crystallization, we demonstrated that the crystal formation of another solute dissolved in the droplets could be triggered by solvent exchange. The length of crystal fibers after the solvent-exchange process was shorter at a faster flow rate. This study may provide further understanding to effectively obtain the crystallization of surface droplets through the solvent-exchange approach.

13.
Soft Matter ; 17(21): 5362-5374, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-33956922

RESUMEN

Flow transport in confined spaces is ubiquitous in technological processes, ranging from separation and purification of pharmaceutical ingredients by microporous membranes and drug delivery in biomedical treatment to chemical and biomass conversion in catalyst-packed reactors and carbon dioxide sequestration. In this work, we suggest a distinct pathway for enhanced liquid transport in a confined space via propelling microdroplets. These microdroplets can form spontaneously from localized liquid-liquid phase separation as a ternary mixture is diluted by a diffusing poor solvent. High speed images reveal how the microdroplets grow, break up and propel rapidly along the solid surface, with a maximal velocity up to ∼160 µm s-1, in response to a sharp concentration gradient resulting from phase separation. The microdroplet propulsion induces a replenishing flow between the walls of the confined space towards the location of phase separation, which in turn drives the mixture out of equilibrium and leads to a repeating cascade of events. Our findings on the complex and rich phenomena of propelling droplets suggest an effective approach to enhanced flow motion of multicomponent liquid mixtures within confined spaces for time effective separation and smart transport processes.


Asunto(s)
Espacios Confinados , Preparaciones Farmacéuticas , Difusión , Membranas , Solventes
14.
Eur Phys J E Soft Matter ; 44(4): 57, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33877477

RESUMEN

In situ observation of precipitation or phase separation induced by solvent addition is important in studying its dynamics. Combined with optical and fluorescence microscopy, microfluidic devices have been leveraged in studying the phase separation in various materials including biominerals, nanoparticles, and inorganic crystals. However, strong scattering from the subphases in the mixture is problematic for in situ study of phase separation with high temporal and spatial resolution. In this work, we present a quasi-2D microfluidic device combined with total internal reflection microscopy as an approach for in situ observation of phase separation. The quasi-2D microfluidic device comprises of a shallow main channel and a deep side channel. Mixing between a solution in the main channel (solution A) and another solution (solution B) in the side channel is predominantly driven by diffusion due to high fluid resistance from the shallow height of the main channel, which is confirmed using fluorescence microscopy. Moreover, relying on diffusive mixing, we can control the composition of the mixture in the main channel by tuning the composition of solution B. We demonstrate the application of our method for in situ observation of asphaltene precipitation and [Formula: see text]-alanine crystallization.


Asunto(s)
Dispositivos Laboratorio en un Chip , Microscopía , Difusión
15.
Molecules ; 27(1)2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35011433

RESUMEN

25-hydroxycholesterol (25-HC) is an oxysterol synthesized from cholesterol by cholesterol-25-hydroxylase during cholesterol metabolism. The aim of this study was to verify whether 25-HC induces oxiapoptophagy in fibroblasts. 25-HC not only decreased the survival of L929 cells, but also increased the number of cells with condensed chromatin and altered morphology. Fluorescence-activated cell sorting results showed that there was a dose-dependent increase in the apoptotic populations of L929 cells upon treatment with 25-HC. 25-HC-induced apoptotic cell death was mediated by the death receptor-dependent extrinsic and mitochondria-dependent intrinsic apoptosis pathway, through the cascade activation of caspases including caspase-8, -9, and -3 in L929 cells. There was an increase in the levels of reactive oxygen species and inflammatory mediators such as inducible nitric oxide synthase, cyclooxygenase-2, nitric oxide, and prostaglandin E2 in L929 cells treated with 25-HC. Moreover, 25-HC caused an increase in the expression of beclin-1 and microtubule-associated protein 1A/1B-light chain 3, an autophagy biomarker, in L929 cells. There was a significant decrease in the phosphorylation of protein kinase B (Akt) in L929 cells treated with 25-HC. Taken together, 25-HC induced oxiapoptophagy through the modulation of Akt and p53 cellular signaling pathways in L929 cells.


Asunto(s)
Autofagia/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Hidroxicolesteroles/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Hidroxicolesteroles/química , Mediadores de Inflamación/metabolismo , Ratones , Mitocondrias , Estructura Molecular , Especies Reactivas de Oxígeno/metabolismo
16.
FASEB J ; 33(3): 4021-4034, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30509128

RESUMEN

It is well known that an increase in mechanical loading can induce skeletal muscle hypertrophy, and a long standing model in the field indicates that mechanical loads induce hypertrophy via a mechanism that requires signaling through the mechanistic target of rapamycin complex 1 (mTORC1). Specifically, it has been widely proposed that mechanical loads activate signaling through mTORC1 and that this, in turn, promotes an increase in the rate of protein synthesis and the subsequent hypertrophic response. However, this model is based on a number of important assumptions that have not been rigorously tested. In this study, we created skeletal muscle specific and inducible raptor knockout mice to eliminate signaling by mTORC1, and with these mice we were able to directly demonstrate that mechanical stimuli can activate signaling by mTORC1, and that mTORC1 is necessary for mechanical load-induced hypertrophy. Surprisingly, however, we also obtained multiple lines of evidence that indicate that mTORC1 is not required for a mechanical load-induced increase in the rate of protein synthesis. This observation highlights an important shortcoming in our understanding of how mechanical loads induce hypertrophy and illustrates that additional mTORC1-independent mechanisms play a critical role in this process.-You, J.-S., McNally, R. M., Jacobs, B. L., Privett, R. E., Gundermann, D. M., Lin, K.-H., Steinert, N. D., Goodman, C. A., Hornberger, T. A. The role of raptor in the mechanical load-induced regulation of mTOR signaling, protein synthesis, and skeletal muscle hypertrophy.


Asunto(s)
Músculo Esquelético/metabolismo , Esfuerzo Físico , Proteína Reguladora Asociada a mTOR/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Hipertrofia/etiología , Hipertrofia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Músculo Esquelético/patología , Biosíntesis de Proteínas , Proteína Reguladora Asociada a mTOR/genética , Transducción de Señal
17.
Int J Med Sci ; 17(16): 2496-2504, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33029092

RESUMEN

Background: To maintain the normal pregnancy, suppression of inflammatory signaling pathway is a crucial physiologic response. Dexmedetomidine has been used for labor analgesia or supplement of inadequate regional analgesia during delivery. And it has been reported that dexmedetomidine has an anti-inflammatory effect. In this study, we examined the influence of dexmedetomidine on the expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) and inflammatory cytokines in lipopolysaccharide (LPS)-stimulated human amnion-derived WISH cells. In addition, we evaluated the association of mitogen-activated protein kinase (MAPK) and nuclear factor kappa B (NF-κB) pathway in anti-inflammatory effect of dexmedetomidine. Methods: Human amnion-derived WISH cells were pretreated with various concentrations of dexmedetomidine (0.001-1 µg/ml) for 1 h and after then treated with LPS (1 µg/ml) for 24 h. MTT assay was conducted to evaluate the cytotoxicity. Nitric oxide (NO) production was analyzed using Griess-reaction microassay. RT-PCR was performed for analysis of mRNA expressions of COX-2, PGE2, tumor necrosis factor (TNF)-α and interlukin (IL)-1ß. Protein expressions of COX-2, PGE2, p38 and NF-κB were analyzed by western blotting. Results: LPS and dexmedetomidine had no cytotoxic effect on WISH cells. There was no difference in NO production after dexmedetomidine pretreatment. The mRNA and protein expressions of COX-2 and PGE2 were decreased by dexmedetomidine pretreatment in LPS-treated WISH cells. Dexmedetomidine also attenuated the LPS-induced mRNA expression of TNF-α and IL-1ß. The activation of p38 and NF-κB was suppressed by dexmedetomidine pretreatment in LPS-treated WISH cells. Conclusion: We demonstrated that dexmedetomidine pretreatment suppressed the expressions of inflammatory mediators increased by LPS. In addition, this study suggests that anti-inflammatory effect of dexmedetomidine on WISH cells was mediated by the inhibitions of p38 and NF-κB activation.


Asunto(s)
Amnios/efectos de los fármacos , Antiinflamatorios/farmacología , Dexmedetomidina/farmacología , Inflamación/tratamiento farmacológico , Amnios/citología , Amnios/inmunología , Antiinflamatorios/uso terapéutico , Línea Celular , Ciclooxigenasa 2/metabolismo , Dexmedetomidina/uso terapéutico , Dinoprostona/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Inflamación/metabolismo , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/inmunología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
18.
J Craniofac Surg ; 31(1): e10-e13, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31403515

RESUMEN

BACKGROUND: Various surgical methods have been used for reconstruction of an amputated ear, including microsurgical replantation and delayed reconstruction using synthetic material or autologous rib cartilage. The authors share our experience of immediate reconstruction using amputated cartilage and discuss the advantages compared to other techniques of reconstruction. MATERIALS AND METHODS: The authors retrospectively reviewed the medical records of 3 patients who underwent immediate reconstruction of amputated ear by a single operator. In the cases, the amputees were washed; the skin and cartilage were separated. The ear cartilage was fixed to its original position with non-absorbable suture. Regional fascia flap was elevated and covered the ear cartilage. The amputee skin was redraped to cover the fascia flap. Several months after the operation, photographic assessment was done. RESULTS: All 3 cases showed well-defined convolution, tolerable skin color, and patient satisfaction without any major complications. A patient showed mild temporal incision site alopecia. CONCLUSION: The above immediate reconstruction method can achieve reliable and favorable result with minimal complications.


Asunto(s)
Amputados , Oído/cirugía , Adulto , Fascia , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Procedimientos de Cirugía Plástica , Estudios Retrospectivos , Colgajos Quirúrgicos
19.
Int J Mol Sci ; 21(13)2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-32635386

RESUMEN

It is well established that physiological stress has an adverse effect on the male reproductive system. Experimental studies have demonstrated the promising effects of MOTILIPERM in male infertility. MOTILIPERM extract is composed of three crude medicinal herbs: Morinda officinalis How (Rubiaceae) roots, Allium cepa L. (Liliaceae) outer scales, and Cuscuta chinensis Lamark (convolvulaceae) seeds. The present study aimed to investigate the possible mechanisms responsible for the effects of MOTILIPERM on testicular dysfunction induced by immobilization stress. Fifty male Sprague Dawley rats were divided into five groups (10 rats each): a normal control group (CTR), a control group administered MOTILIPERM 200 mg/kg (M 200), an immobilization-induced stress control group (S), an immobilization-induced stress group administered MOTILIPERM 100 mg/kg (S + M 100), and MOTILIPERM 200 mg/kg (S + M 200). Stressed rats (n = 30) were subjected to stress by immobilization for 6 h by placing them in a Perspex restraint cage, while controls (n = 20) were maintained without disturbance. Rats were administrated 100 or 200 mg/kg MOTILIPERM once daily for 30 days 1 h prior to immobilization. At the end of the treatment period, we measured body and reproductive organ weight; sperm parameters; histopathological damage; reproductive hormone levels; steroidogenic acute regulatory protein (StAR); biomarkers of oxidative stress; and apoptosis markers. MOTILIPERM treatment improved testicular dysfunction by up-regulating (p < 0.05) sperm count, sperm motility, serum testosterone level, StAR protein level, Johnsen score, and spermatogenic cell density in stressed rats. MOTILIPERM decreased oxidative stress by increasing (p < 0.05) testicular superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione peroxidase-4 (GPx 4), catalase, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase 1 (HO-1) levels and decreasing (p < 0.05) malondialdehyde (MDA) and reactive oxygen species/reactive nitrogen species (ROS/RNS) levels. Furthermore, MOTILIPERM down-regulated (p < 0.05) cleaved caspase 3 and BCL2 associated X protein (Bax) levels; increased pro caspase-3 and B-cell lymphoma 2 (Bcl-2) levels; and upregulated testicular germ cell proliferation in stressed rats. The number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells and serum luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels also significantly (p < 0.05) decreased after pretreatment with MOTILIPERM in stressed rats. Collectively, our results suggest that, in immobilization-mediated stress-induced testicular dysfunction, MOTILIPERM sustains normal spermatogenesis via antioxidant and anti-apoptotic activities by activating the NRF/HO-1 signaling pathway.


Asunto(s)
Extractos Vegetales/farmacología , Testículo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Cuscuta/química , Hemo Oxigenasa (Desciclizante)/metabolismo , Infertilidad Masculina/tratamiento farmacológico , Infertilidad Masculina/patología , Infertilidad Masculina/fisiopatología , Masculino , Medicina Tradicional Coreana , Morinda/química , Factor 2 Relacionado con NF-E2/metabolismo , Cebollas/química , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Extractos Vegetales/química , Plantas Medicinales/química , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Espermatogénesis/efectos de los fármacos , Estrés Fisiológico , Testículo/patología , Testículo/fisiopatología
20.
Korean J Physiol Pharmacol ; 24(3): 249-257, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32392916

RESUMEN

The aim of the present study was to investigate the pathophysiological etiology of osteoarthritis that is mediated by the apoptosis of chondrocytes exposed to 25-hydroxycholesterol (25-HC), an oxysterol synthesized by the expression of cholesterol-25-hydroxylase (CH25H) under inflammatory conditions. Interleukin-1ß induced the apoptosis of chondrocytes in a dose- dependent manner. Furthermore, the production of 25-HC increased in the chondrocytes treated with interleukin-1ß through the expression of CH25H. 25-HC decreased the viability of chondrocytes. Chondrocytes with condensed nucleus and apoptotic populations increased by 25-HC. Moreover, the activity and expression of caspase-3 were increased by the death ligand-mediated extrinsic and mitochondria-dependent intrinsic apoptotic pathways in the chondrocytes treated with 25-HC. Finally, 25-HC induced not only caspase-dependent apoptosis, but also induced proteoglycan loss in articular cartilage ex vivo cultured rat knee joints. These data indicate that 25-HC may act as a metabolic pathophysiological factor in osteoarthritis that is mediated by progressive chondrocyte death in the articular cartilage with inflammatory condition.

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