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1.
J Chem Phys ; 159(16)2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37873959

RESUMEN

Realizing the graded bandgap in absorber layer is very essential for high efficient thin film solar cells. However, such bandgap modification in kesterite-structured Cu2ZnSnSe4 is normally realized via high temperature sulfurization process (above 500°C), which is not only difficult to control the sulfurization depth, but also introduces additional deep defects because of the decomposition of absorber layer at such high temperature. In this study, a low-temperature sulfurization process (150°C) is developed. Such process not only inhibits the decomposition of Cu2ZnSnSe4 films and controls the elemental distribution very well, but also increase the surface bandgap of the absorber layer and form a gradient energy bandgap. Also, the density of deep-level defects in the Cu2ZnSnSe4 layer is reduced. As a consequence, the open circuit voltage of the solar cell is improved by 60 mV. This study paves the way towards the high efficient kesterite solar cell and other solar cells.

2.
Anal Chem ; 95(31): 11785-11792, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37418537

RESUMEN

The research on lipid droplets (LDs) has attracted great attention in the field of biomedical science in recent years. LD malfunction is found to be associated with the development of acute kidney injury (AKI). To monitor this biological process and explain related pathological behavior, the development of excellent LD fluorescent probes with a polarity-sensitive character would provide a desirable strategy. Herein, we designed a new polarity-susceptible fluorescent probe named LD-B with LD targetability, which exhibits very weak fluorescence in highly polar solvents based on the twisted intramolecular charge transfer effect but enhanced fluorescence in low polar environments, enabling us to visualize polarity alteration. The probe LD-B also possesses the merits of intense near-infrared (NIR) emission, good photostability, large Stokes shift, low toxicity, faster metabolic rate, and wash-free ability; thereby, it would contribute to efficient LD fluorescence visualization application. Using LD-B via confocal laser scanning fluorescence imaging and a small-animal imaging system in vivo, we first manifested a prominent rise of LD polarity in contrast-induced AKI (CI-AKI), not only at the cellular level but also in animals in vivo. Furthermore, the in vivo studies suggest that LD-B could accumulate in the kidney. In addition, the normal cell lines (including kidney cells) exhibiting a greater polarity of LDs than the cancer cells have been demonstrated systemically. Altogether, our work presents an effective approach for the medical diagnosis of LDs related to CI-AKI and identification of potential therapeutic markers.


Asunto(s)
Lesión Renal Aguda , Gotas Lipídicas , Animales , Colorantes Fluorescentes/toxicidad , Fluorescencia , Solventes , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/diagnóstico por imagen
3.
Cell Rep Methods ; 3(2): 100394, 2023 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-36936069

RESUMEN

Intracellular long-chain acyl-coenzyme As (LC-acyl-CoAs) are thought to be under tight spatial and temporal controls, yet the ability to image LC-acyl-CoAs in live cells is lacking. Here, we developed a fluorescence resonance energy transfer (FRET) sensor for LC-acyl-CoAs based on the allosterically regulated interaction between α/ß hydrolase domain-containing 5 (ABHD5) and Perilipin 5. The genetically encoded sensor rapidly detects intracellular LC-acyl-CoAs generated from exogenous and endogenous fatty acids (FAs), as well as synthetic ABHD5 ligands. Stimulation of lipolysis in brown adipocytes elevated intracellular LC-acyl-CoAs in a cyclic fashion, which was eliminated by inhibiting PNPLA2 (ATGL), the major triglyceride lipase. Interestingly, inhibition of LC-acyl-CoA transport into mitochondria elevated intracellular LC-acyl-CoAs and dampened their cycling. Together, these observations reveal an intimate feedback control between LC-acyl-CoA generation from lipolysis and utilization in mitochondria. We anticipate that this sensor will be an important tool to dissect intracellular LC-acyl-CoA dynamics as well to discover novel synthetic ABHD5 ligands.


Asunto(s)
Acilcoenzima A , Transferencia Resonante de Energía de Fluorescencia , Acilcoenzima A/metabolismo , Lipólisis/fisiología , Lipasa/genética , Ácidos Grasos
4.
Small ; 19(22): e2300634, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36855059

RESUMEN

Increasing the fill factor (FF) and the open-circuit voltage (VOC ) simultaneously together with non-decreased short-circuit current density (JSC ) are a challenge for highly efficient Cu2 ZnSn(S,Se)4 (CZTSSe) solar cells. Aimed at such target in CZTSSe solar cells, a synergistic strategy to tailor the recombination in the bulk and at the heterojunction interface has been developed, consisting of atomic-layer deposited aluminum oxide (ALD-Al2 O3 ) and (NH4 )2 S treatment. With this strategy, deep-level CuZn defects are converted into shallower VCu defects and improved crystallinity, while the surface of the absorber is optimized by removing Zn- and Sn-related impurities and incorporating S. Consequently, the defects responsible for recombination in the bulk and at the heterojunction interface are effectively passivated, thereby prolonging the minority carrier lifetime and increasing the depletion region width, which promote carrier collection and reduce charge loss. As a consequence, the VOC deficit decreases from 0.607 to 0.547 V, and the average FF increases from 64.2% to 69.7%, especially, JSC does not decrease. Thus, the CZTSSe solar cell with the remarkable efficiency of 13.0% is fabricated. This study highlights the increased FF together with VOC simultaneously to promote the efficiency of CZTSSe solar cells, which could also be applied to other photoelectronic devices.

5.
Front Mol Biosci ; 9: 935375, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35836935

RESUMEN

Alpha/beta hydrolase domain-containing 5 (ABHD5), also termed CGI-58, is the key upstream activator of adipose triglyceride lipase (ATGL), which plays an essential role in lipid metabolism and energy storage. Mutations in ABHD5 disrupt lipolysis and are known to cause the Chanarin-Dorfman syndrome. Despite its importance, the structure of ABHD5 remains unknown. In this work, we combine computational and experimental methods to build a 3D structure of ABHD5. Multiple comparative and machine learning-based homology modeling methods are used to obtain possible models of ABHD5. The results from Gaussian accelerated molecular dynamics and experimental data of the apo models and their mutants are used to select the most likely model. Moreover, ensemble docking is performed on representative conformations of ABHD5 to reveal the binding mechanism of ABHD5 and a series of synthetic ligands. Our study suggests that the ABHD5 models created by deep learning-based methods are the best candidate structures for the ABHD5 protein. The mutations of E41, R116, and G328 disturb the hydrogen bonding network with nearby residues and suppress membrane targeting or ATGL activation. The simulations also reveal that the hydrophobic interactions are responsible for binding sulfonyl piperazine ligands to ABHD5. Our work provides fundamental insight into the structure of ABHD5 and its ligand-binding mode, which can be further applied to develop ABHD5 as a therapeutic target for metabolic disease and cancer.

6.
Ann Palliat Med ; 11(2): 756-765, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35249352

RESUMEN

BACKGROUND: The treatment of herpes zoster (HZ) by the traditional Chinese medicine of acupuncture is attracting attention. However, there is still a controversy about the effectiveness and safety of acupuncture treatment of HZ. METHODS: Articles on randomized controlled trials examining acupuncture and Western medicine treatments of HZ published since the establishment of the PubMed, Embase, Medline, and Chinese Biomedical Literature (CBM) databases to March 2021 were electronically retrieved. The Cochrane System Evaluation Manual was used for the data analysis with Review Manager 5.3 software, and the Cochrane Handbook version 5.3 systematic review writing manual was adopted to evaluate the risk of bias. RESULTS: In total, 11 articles, comprising 1,156 patients (585 in the experimental group and 571 in the control group) were included in the meta-analysis, and the results showed that the treatments used in the experimental and control groups were significant differences of total treatment efficiency [odds ratio (OR) =6.76; 95% confidence interval (CI): 3.46 to 13.21; P<0.05] in terms of the incidence of posterior neuralgia (OR =0.07; 95% CI: 0.02 to 0.21; P<0.05), pain-relief time [mean difference (MD) =-2.17; 95% CI: -2.90 to -1.44; P<0.05], shingles time (MD =-1.61; 95% CI: -2.84 to -0.38; P<0.05), and scabbing time (MD =-1.62; 95% CI: -2.64 to -0.61; P<0.05), and patients' visual analogue scale (VAS) pain scores improved [standard MD (SMD) =0.87; 95% CI: 0.01 to 1.73; P=0.05] was no significant difference. DISCUSSIONS: Compared to Western medicine treatments, acupuncture had a better effect on HZ, reduced the posterior neuralgia rate of patients, and shortened the course of treatment, but had no obvious effect on the relief of pain.


Asunto(s)
Terapia por Acupuntura , Herpes Zóster , Neuralgia , Terapia por Acupuntura/efectos adversos , Terapia por Acupuntura/métodos , Herpes Zóster/terapia , Humanos , Medicina Tradicional China , Manejo del Dolor
7.
Sci Rep ; 12(1): 2565, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35173175

RESUMEN

Alpha/beta hydrolase domain-containing protein 5 (ABHD5) is a highly conserved protein that regulates various lipid metabolic pathways via interactions with members of the perilipin (PLIN) and Patatin-like phospholipase domain-containing protein (PNPLA) protein families. Loss of function mutations in ABHD5 result in Chanarin-Dorfman Syndrome (CDS), characterized by ectopic lipid accumulation in numerous cell types and severe ichthyosis. Recent data demonstrates that ABHD5 is the target of synthetic and endogenous ligands that might be therapeutic beneficial for treating metabolic diseases and cancers. However, the structural basis of ABHD5 functional activities, such as protein-protein interactions and ligand binding is presently unknown. To address this gap, we constructed theoretical structural models of ABHD5 by comparative modeling and topological shape analysis to assess the spatial patterns of ABHD5 conformations computed in protein dynamics. We identified functionally important residues on ABHD5 surface for lipolysis activation by PNPLA2, lipid droplet targeting and PLIN-binding. We validated the computational model by examining the effects of mutating key residues in ABHD5 on an array of functional assays. Our integrated computational and experimental findings provide new insights into the structural basis of the diverse functions of ABHD5 as well as pathological mutations that result in CDS.


Asunto(s)
1-Acilglicerol-3-Fosfato O-Aciltransferasa/química , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/metabolismo , Biología Computacional/métodos , Lipasa/metabolismo , Gotas Lipídicas/metabolismo , Mutación , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , Humanos , Ligandos , Gotas Lipídicas/química , Conformación Proteica
8.
J Ethnopharmacol ; 285: 114834, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34801609

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Semen Cuscutae, called Tu-si-zi in Chinese, is a kind of dried mature seed in the Convolvulaceae family. It mainly distributes in China, Korea, Pakistan, Vietnam, India and Thailand. It is used as a kidney-tonifying drug for treatment of aging related diseases such as osteoporosis in traditional Chinese medicine. However, the exact mechanisms on bone resorption are poorly studied. AIM OF THE STUDY: The aim of this study was to investigate the potential effect of Semen Cuscutae on ovariectomy (OVX)-induced osteoporosis in mice and clarify the exact mechanisms by which Semen Cuscutae exert the anti-osteoporosis effect. MATERIALS AND METHODS: Qualitative and quantitative analyses of Semen Cuscutae were performed by UPLC-Q-TOF-MS and HPLC-MS/MS, respectively. Changes in bone mineral density (BMD) induced by OVX in mice were measured by dual-energy X-ray absorptiometry and micro-computed tomography (µCT). Tartrate-resistant acid phosphatase (TRAP) staining as well as hematoxylin and eosin (HE) staining were used to observe bone microarchitectural changes. ELISA kits were used to assess the therapeutic effects of Semen Cuscutae on the serum levels of osteoprotegerin (OPG), tartrate-resistant acid phosphatase 5b (TRACP-5b), and receptor activator of nuclear factor-κB (RANKL). The effect of Semen Cuscutae on primary cell viability was assessed using CCK-8 and anti-tartrate phosphatase assays. TRAP staining and actin ring staining were used to observe the effect of Semen Cuscutae on osteoclast differentiation. Western blotting was used to measure the effects of Semen Cuscutae on expressions of NFATC1, c-Src kinase, and c-fos. RESULTS: Results from UPLC-Q-TOF-MS showed that the main components of Semen Cuscutae were flavonoid compounds that included quercitrin, quercetin, hyperoside, caffeic acid, rutin, chlorogenic acid, luteolin, apigenin, kaempferol, isoquercetin, cryptochlorogenic acid, isorhamnetin-3-O-glucoside, and astragalin. After the Semen Cuscutae extract was orally administered to OVX mice, bone density increased (P < 0.01) and bone microstructure was significantly improved (P < 0.01 or 0.05). Additionally, Semen Cuscutae exhibited a significant descending effect in the levels of serum TRACP-5b and RANKL, while there was a significant increase in OPG in the Semen Cuscutae group compared with the OVX group, especially at high doses. Moreover, we found that increasing of c-fos, c-Src kinase, and NFATC1 protein expressions were reversed by Semen Cuscutae in vitro and in vivo. CONCLUSIONS: Our results showed that Semen Cuscutae exhibited anti-osteoporosis effects through the c-fos/c-Src kinase/NFATC1 signaling pathway.


Asunto(s)
Resorción Ósea , Medicamentos Herbarios Chinos/farmacología , Osteoporosis , Transducción de Señal/efectos de los fármacos , Absorciometría de Fotón/métodos , Animales , Conservadores de la Densidad Ósea/farmacología , Resorción Ósea/diagnóstico por imagen , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Proteína Tirosina Quinasa CSK/metabolismo , Ratones , Factores de Transcripción NFATC/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/fisiología , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Microtomografía por Rayos X/métodos
9.
Blood Sci ; 3(1): 6-13, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35399204

RESUMEN

To understand the behavior and function of bone-marrow mesenchymal cells (BMMCs), we overviewed the morphological presentation of BMMCs in bone-marrow granules (b-BMMCs), isolated BMMCs (i-BMMCs), and BMMCs (c-BMMCs) cultured in H4434 methylcellulose semisolid and MEM media. All samples were derived from bone-marrow aspirates of 30 patients with hematocytopenia. Light microscopy exhibited b-BMMCs and i-BMMCs characterized by abundant cytoplasm and irregular shape in bone-marrow smears, as well as c-BMMCs in culture conditions. Scanning electron microscopy demonstrated cultured c-BMMCs with a sheet-like feature enveloping hematopoietic cells. Transmission electron microscopy revealed b-BMMCs constructing a honeycomb-like structure by thin bifurcate processes among hematopoietic cells. Furthermore, i-BMMCs had bifurcate parapodiums on the surface and prominent rough endoplasmic reticulum (rER) connected with the plasmalemma of the parapodiums. The detailed images suggested that rER may serve as a membrane resource for plasmalemmal expansion in BMMCs in bone marrow.

10.
Artículo en Inglés | MEDLINE | ID: mdl-31885656

RESUMEN

This study developed a method for simultaneous determination of 13 elements of Semen Cuscutae (quercitrin, quercetin, hyperoside, caffeic acid, chlorogenic acid, luteolin, apigenin, kaempferol, isoquercitrin, cryptochlorogenic acid, isorhamnetin-3-O-glucoside, astragalin, and rutin) in rat plasma using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in the negative MRM mode. The analytes were analyzed with CORTECS®C18 column (4.6 × 150 mm, 2.7 µm) with mobile phases consisting of 0.1% formic acid in water (A) and acetonitrile (B). The intra- and interday precision of the target compounds were expressed as relative standard deviation (RSD) in the range of 0.5%-10.4%, and the accuracy of the target compounds was expressed as relative error (RE) not exceeding ±14.5% for all analytes. In the meantime, the extraction recovery of the target compounds in plasma samples ranged from 87.4% to 106.2% and matrix effect from 81.0% to 115.5%. The established method was successfully accomplished for the pharmacokinetic study of the analytes in rat plasma samples following oral administration of Semen Cuscutae extract, and the pharmacokinetic parameters of seven compounds were obtained.

11.
Mol Metab ; 29: 55-64, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31668392

RESUMEN

OBJECTIVE: Fatty acids are important for biological function; however, in excess, they can cause metabolic dysregulation. Methods to image and detect fatty acids in real time are lacking. Therefore, the current study examined the dynamics of fatty acid trafficking and signaling utilizing novel fluorescent and luminescent approaches. METHODS: We generated fluorescent and luminescent-based genetically-encoded sensors based upon the ligand-dependent interaction between PPARα and SRC-1 to image and detect cellular dynamics of fatty acid trafficking. RESULTS: The use of a fluorescent sensor demonstrates that fatty acids traffic rapidly from lipid droplets to the nucleus. Both major lipases ATGL and HSL contribute to fatty acid signaling from lipid droplet to nucleus, however, their dynamics differ. Furthermore, direct activation of lipolysis, independent of receptor-mediated signaling is sufficient to promote lipid droplet to nuclear trafficking of fatty acids. A luminescent-based sensor that reports intracellular fatty acid levels is amenable to high-throughput analysis. CONCLUSIONS: Fatty acids traffic from lipid droplets to the nucleus within minutes of stimulated lipolysis. Genetically-encoded fluorescent and luminescent based sensors can be used to probe the dynamics of fatty acid trafficking and signaling.


Asunto(s)
Ácidos Grasos/metabolismo , Colorantes Fluorescentes/química , Microscopía Fluorescente , Transporte Biológico , Núcleo Celular/metabolismo , Colorimetría , Ácidos Grasos/análisis , Genes Reporteros , Células HEK293 , Humanos , Ligandos , Gotas Lipídicas/metabolismo , Lipólisis , Coactivador 1 de Receptor Nuclear/genética , Coactivador 1 de Receptor Nuclear/metabolismo , PPAR alfa/química , PPAR alfa/genética , PPAR alfa/metabolismo , Transducción de Señal , Esterol Esterasa/metabolismo
12.
Clin Exp Allergy ; 49(2): 180-189, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30126028

RESUMEN

BACKGROUND: Mechanisms underlying oral immunotherapy (OIT) are unclear and the effects on immune cells at varying maintenance doses are unknown. OBJECTIVE: We aimed to determine the immunologic changes caused by peanut OIT in preschool aged children and determine the effect on these immune responses in groups ingesting low or high-dose peanut OIT (300 mg or 3000 mg, respectively) as maintenance therapy. METHODS: Blood was drawn at several time-points throughout the OIT protocol and PBMCs isolated and cultured with peanut antigens. Secreted cytokines were quantified via multiplex assay, whereas Treg and peanut-responsive CD4 T cells were studied with flow cytometry. Basophil activation assays were also conducted. RESULTS: Th2-, Th1-, Th9- and Tr1-type cytokines decreased over the course of OIT in groups on high- and low-dose OIT. There were no significant differences detected in cytokine changes between the high- and low-dose groups. The initial increase in both the number of peanut-responsive CD4 T cells and the number of Tregs was transient and no significant differences were found between groups. Basophil activation following peanut stimulation was decreased over the course of OIT and associated with increased peanut-IgG4/IgE ratios. No differences were found between high- and low-dose groups in basophil activation at the time of desensitization or sustained unresponsiveness oral food challenges. CONCLUSIONS AND CLINICAL RELEVANCE: Peanut OIT leads to decreases in pro-allergic cytokines, including IL-5, IL-13, and IL-9 and decreased basophil activation. No differences in T cell or basophil responses were found between subjects on low or high-dose maintenance OIT, which has implications for clinical dosing strategies.


Asunto(s)
Basófilos , Linfocitos T CD4-Positivos , Citocinas/metabolismo , Desensibilización Inmunológica , Hipersensibilidad al Cacahuete , Administración Oral , Basófilos/metabolismo , Basófilos/patología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Preescolar , Femenino , Humanos , Masculino , Hipersensibilidad al Cacahuete/inmunología , Hipersensibilidad al Cacahuete/patología , Hipersensibilidad al Cacahuete/terapia
13.
Molecules ; 23(7)2018 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-29986486

RESUMEN

Epimedium herb is one of the most vital traditional Chinese medicines (TCMs), which is used for "nourishing the kidney and reinforcing the Yang". In the guidance of TCM theory, Epimedium herb is usually processed with lamb oil to increase its efficacy. The contents of active ingredients in different Epimedium are significantly varied, which may derive from their different species, regions and processing methods. In this research, 13 batches of raw Epimedium collected from 6 provinces were identified. After optimization of the processing method of Epimedium, a liquid chromatography⁻mass spectrometry (LC⁻MS/MS) method for simultaneous determination of 16 compounds was established to evaluate the quality of raw and processed. Then the multivariate statistical technique was applied to compare different batches of Epimedium based on the LC⁻MS/MS data. As a conclusion, the herbs collected from 6 areas were ascribed to 5 species by microscopic and appearance features. Meanwhile, all of the raw and processed samples were classified by partial least squares discriminant analysis (PLS-DA) based on the 16 analyzed compounds. The comparison results indicate that processing and species both have important influences on Epimedium compositions contents.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Epimedium/química , Epimedium/clasificación , Cromatografía Líquida de Alta Presión , Análisis de los Mínimos Cuadrados , Extractos Vegetales/análisis , Análisis de Componente Principal , Espectrometría de Masas en Tándem
14.
Cell Mol Biol Lett ; 23: 17, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29736176

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV) infection is causatively associated with a variety of human cancers, including gastric cancer (GC), which has one of the highest mortality rates of all human cancers. Long non-coding RNAs (lncRNAs) show important regulatory roles in human GC. SNHG8 is a recently identified lncRNA that was reported to show abnormal expression pattern in GC. However, little is known of its biological function in EBV-associated GC. METHODS: We used cell viability, colony formation and cell cycle assays to investigate the roles of lncRNA SNHG8 in the cell growth of EBV-associated GC. RESULTS: The transcript levels of SNHG8 in the cultured EBV-associated GC cells were significantly higher in the cultured EBV-associated GC cells compared with the levels in normal human gastric mucosal cells and EBV-negative GC cells. Knockdown of SNHG8 with specific shRNAs inhibited cell proliferation and colony formation and arrested the cell cycle in the G0/G1 phase in vitro. We also found that knockdown of SNHG8 suppressed tumor growth in vivo. CONCLUSIONS: These data indicate the pro-oncogenic potential of SNHG8 in EBV-associated GC, meaning it is a latent therapeutic target for the treatment of this type of cancer.


Asunto(s)
Infecciones por Virus de Epstein-Barr/metabolismo , ARN Largo no Codificante/metabolismo , Neoplasias Gástricas/virología , Animales , Apoptosis , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Largo no Codificante/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Elife ; 62017 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-28244868

RESUMEN

Perilipin (PLIN) proteins constitute an ancient family important in lipid droplet (LD) formation and triglyceride metabolism. We identified an additional PLIN clade (plin6) that is unique to teleosts and can be traced to the two whole genome duplications that occurred early in vertebrate evolution. Plin6 is highly expressed in skin xanthophores, which mediate red/yellow pigmentation and trafficking, but not in tissues associated with lipid metabolism. Biochemical and immunochemical analyses demonstrate that zebrafish Plin6 protein targets the surface of pigment-containing carotenoid droplets (CD). Protein kinase A (PKA) activation, which mediates CD dispersion in xanthophores, phosphorylates Plin6 on conserved residues. Knockout of plin6 in zebrafish severely impairs the ability of CD to concentrate carotenoids and prevents tight clustering of CD within carotenoid bodies. Ultrastructural and functional analyses indicate that LD and CD are homologous structures, and that Plin6 was functionalized early in vertebrate evolution for concentrating and trafficking pigment.


Asunto(s)
Gotas Lipídicas/metabolismo , Perilipina-1/metabolismo , Pez Cebra , Animales , Carotenoides/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Perfilación de la Expresión Génica , Técnicas de Inactivación de Genes , Perilipina-1/genética , Fosforilación , Procesamiento Proteico-Postraduccional
16.
Sci Rep ; 7: 42589, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28211464

RESUMEN

Alpha-beta hydrolase domain-containing 5 (ABHD5), the defective gene in human Chanarin-Dorfman syndrome, is a highly conserved regulator of adipose triglyceride lipase (ATGL)-mediated lipolysis that plays important roles in metabolism, tumor progression, viral replication, and skin barrier formation. The structural determinants of ABHD5 lipolysis activation, however, are unknown. We performed comparative evolutionary analysis and structural modeling of ABHD5 and ABHD4, a functionally distinct paralog that diverged from ABHD5 ~500 million years ago, to identify determinants of ABHD5 lipolysis activation. Two highly conserved ABHD5 amino acids (R299 and G328) enabled ABHD4 (ABHD4 N303R/S332G) to activate ATGL in Cos7 cells, brown adipocytes, and artificial lipid droplets. The corresponding ABHD5 mutations (ABHD5 R299N and ABHD5 G328S) selectively disrupted lipolysis without affecting ATGL lipid droplet translocation or ABHD5 interactions with perilipin proteins and ABHD5 ligands, demonstrating that ABHD5 lipase activation could be dissociated from its other functions. Structural modeling placed ABHD5 R299/G328 and R303/G332 from gain-of-function ABHD4 in close proximity on the ABHD protein surface, indicating they form part of a novel functional surface required for lipase activation. These data demonstrate distinct ABHD5 functional properties and provide new insights into the functional evolution of ABHD family members and the structural basis of lipase regulation.


Asunto(s)
1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , Lipólisis/genética , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/química , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/metabolismo , Adipocitos Marrones/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Células COS , Línea Celular , Chlorocebus aethiops , Expresión Génica , Técnicas de Silenciamiento del Gen , Lipasa/metabolismo , Gotas Lipídicas , Lisofosfolipasa/química , Lisofosfolipasa/genética , Lisofosfolipasa/metabolismo , Ratones , Modelos Moleculares , Mutación , Unión Proteica , Conformación Proteica , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas , Relación Estructura-Actividad
17.
Cell Metab ; 22(5): 851-60, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26411340

RESUMEN

Fat and muscle lipolysis involves functional interactions of adipose triglyceride lipase (ATGL), α-ß hydrolase domain-containing protein 5 (ABHD5), and tissue-specific perilipins 1 and 5 (PLIN1 and PLIN5). ABHD5 potently activates ATGL, but this lipase-promoting activity is suppressed when ABHD5 is bound to PLIN proteins on lipid droplets. In adipocytes, protein kinase A (PKA) phosphorylation of PLIN1 rapidly releases ABHD5 to activate ATGL, but mechanisms for rapid regulation of PLIN5-ABHD5 interaction in muscle are unknown. Here, we identify synthetic ligands that release ABHD5 from PLIN1 or PLIN5 without PKA activation and rapidly activate adipocyte and muscle lipolysis. Molecular imaging and affinity probe labeling demonstrated that ABHD5 is directly targeted by these synthetic ligands and additionally revealed that ABHD5-PLIN interactions are regulated by endogenous ligands, including long-chain acyl-CoA. Our results reveal a new locus of lipolysis control and suggest ABHD5 ligands might be developed into novel therapeutics that directly promote fat catabolism.


Asunto(s)
1-Acilglicerol-3-Fosfato O-Aciltransferasa/metabolismo , Proteínas Portadoras/metabolismo , Lipólisis/genética , Fosfoproteínas/metabolismo , Proteínas/metabolismo , 1-Acilglicerol-3-Fosfato O-Aciltransferasa/genética , Células 3T3-L1 , Acilcoenzima A/metabolismo , Adipocitos/metabolismo , Animales , Proteínas Portadoras/genética , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Humanos , Ligandos , Ratones , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Perilipina-1 , Perilipina-5 , Fosfoproteínas/genética , Proteínas/genética
18.
PLoS One ; 9(7): e102582, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25019272

RESUMEN

Rb is a tumor suppressor, and regulates various biological progresses, such as cell proliferation, development, metabolism and cell death. In the current study, we show that Rb knockout in 3T3 cells leads to oxidative redox state and low mitochondrial membrane potential by regulating mitochondrial activity. Our results indicate that Rb plays an important role in controlling redox homeostasis. More importantly, the functions of Rb in modulating cell proliferation, death and transformation are, at least in part, mediated by its controlling cellular redox state. In addition, our results also suggest that the cellular redox state possibly determines various biological activities, including cell survival, death and transformation, where Rb is functioning as a regulator of redox homeostasis.


Asunto(s)
Transformación Celular Neoplásica , Proteína de Retinoblastoma/metabolismo , Células 3T3 , Animales , Apoptosis , Proliferación Celular , Homeostasis , Potencial de la Membrana Mitocondrial , Ratones , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo
19.
Mech Dev ; 133: 64-76, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24946235

RESUMEN

Cyclin J (CycJ) is a poorly characterized member of the Cyclin superfamily of cyclin-dependent kinase regulators, many of which regulate the cell cycle or transcription. Although CycJ is conserved in metazoans its cellular function has not been identified and no mutant defects have been described. In Drosophila, CycJ transcript is present primarily in ovaries and very early embryos, suggesting a role in one or both of these tissues. The CycJ gene (CycJ) lies immediately downstream of armitage (armi), a gene involved in the Piwi-associated RNA (piRNA) pathways that are required for silencing transposons in the germline and adjacent somatic cells. Mutations in armi result in oogenesis defects but a role for CycJ in oogenesis has not been defined. Here we assessed oogenesis in CycJ mutants in the presence or absence of mutations in armi or other piRNA pathway genes. CycJ null ovaries appeared normal, indicating that CycJ is not essential for oogenesis under normal conditions. In contrast, armi null ovaries produced only two egg chambers per ovariole and the eggs had severe axis specification defects, as observed previously for armi and other piRNA pathway mutants. Surprisingly, the CycJ armi double mutant failed to produce any mature eggs. The double null ovaries generally had only one egg chamber per ovariole and the egg chambers frequently contained an overabundance of differentiated germline cells. Production of these compound egg chambers could be suppressed with CycJ transgenes but not with mutations in the checkpoint gene mnk, which suppress oogenesis defects in armi mutants. The CycJ null showed similar genetic interactions with the germline and somatic piRNA pathway gene piwi, and to a lesser extent with aubergine (aub), a member of the germline-specific piRNA pathway. The strong genetic interactions between CycJ and piRNA pathway genes reveal a role for CycJ in early oogenesis. Our results suggest that CycJ is required to regulate egg chamber production or maturation when piRNA pathways are compromised.


Asunto(s)
Ciclinas/genética , Ciclinas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Oogénesis/genética , ARN Interferente Pequeño/genética , Animales , Animales Modificados Genéticamente , Ciclinas/deficiencia , Proteínas de Drosophila/deficiencia , Drosophila melanogaster/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Genes de Insecto , Mutación , Ovario/citología , Ovario/crecimiento & desarrollo , ARN Helicasas/deficiencia , ARN Helicasas/genética
20.
Ultrastruct Pathol ; 38(4): 256-60, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24579890

RESUMEN

OBJECT: To study the relationship between monocyte/histiocyte activation and myelodysplastic syndrome (MDS). METHODS: Analyzing ultrastructure and myeloperoxidase reaction of nucleated cells in bone marrow from 59 cases of MDS by transmission electron microscopy. Four groups of MDS were subdivided on the basis of their content of activated inflammatory cells - morbid hematopoiesis with minimal inflammatory cell activation (MH-MICA); MDS with monocytic system activation (MSA); MDS with lymphocyte activation (LCA); and MDS with granulocyte activation (GCA). RESULTS: About 20, 22, 7, and 10 cases were classified as MH-MICA (34%), MSA (37%), LCA (12%), and GCA sub-types (17%), respectively. About 3, 5, 0, and 3 cases from MH-MICA, MSA, LCA, and GCA, respectively, underwent leukemic transformation within 2 years. CONCLUSION: The findings suggest that activation of inflammatory cells in bone marrow is an important feature of MDS, and that monocytes/histocytes are perhaps the most prominent cellular participants in the pathogenesis of MDS.


Asunto(s)
Células de la Médula Ósea/patología , Monocitos/patología , Síndromes Mielodisplásicos/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Adulto Joven
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