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1.
Proc Natl Acad Sci U S A ; 121(25): e2400546121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38857407

RESUMEN

Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that C─C bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.

2.
Nature ; 577(7788): 121-126, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31853060

RESUMEN

Modifications of histone proteins have essential roles in normal development and human disease. Recognition of modified histones by 'reader' proteins is a key mechanism that mediates the function of histone modifications, but how the dysregulation of these readers might contribute to disease remains poorly understood. We previously identified the ENL protein as a reader of histone acetylation via its YEATS domain, linking it to the expression of cancer-driving genes in acute leukaemia1. Recurrent hotspot mutations have been found in the ENL YEATS domain in Wilms tumour2,3, the most common type of paediatric kidney cancer. Here we show, using human and mouse cells, that these mutations impair cell-fate regulation by conferring gain-of-function in chromatin recruitment and transcriptional control. ENL mutants induce gene-expression changes that favour a premalignant cell fate, and, in an assay for nephrogenesis using murine cells, result in undifferentiated structures resembling those observed in human Wilms tumour. Mechanistically, although bound to largely similar genomic loci as the wild-type protein, ENL mutants exhibit increased occupancy at a subset of targets, leading to a marked increase in the recruitment and activity of transcription elongation machinery that enforces active transcription from target loci. Furthermore, ectopically expressed ENL mutants exhibit greater self-association and form discrete and dynamic nuclear puncta that are characteristic of biomolecular hubs consisting of local high concentrations of regulatory factors. Such mutation-driven ENL self-association is functionally linked to enhanced chromatin occupancy and gene activation. Collectively, our findings show that hotspot mutations in a chromatin-reader domain drive self-reinforced recruitment, derailing normal cell-fate control during development and leading to an oncogenic outcome.


Asunto(s)
Linaje de la Célula , Cromatina/genética , Proteínas de Unión al ADN/metabolismo , Mutación con Ganancia de Función , Factores de Transcripción/metabolismo , Animales , Diferenciación Celular , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Células HEK293 , Humanos , Ratones , Nefronas/metabolismo , Nefronas/patología , Factores de Transcripción/química , Factores de Transcripción/genética
3.
J Biol Chem ; : 107609, 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39074634

RESUMEN

ADP-ribosylation (ADPRylation) is a post-translational modification (PTM) of proteins mediated by the activity of a variety of ADP-ribosyltransferase (ART) enzymes, such as the Poly (ADP-ribose) Polymerase (PARP) family of proteins. This PTM is diverse in both form and biological functions, which makes it a highly interesting modification, but difficult to study due to limitations in reagents available to detect the diversity of ADP-ribosylation. Recently we developed a set of recombinant antibody-like ADP-ribose binding proteins using naturally occurring ADPR binding domains (ARBDs), including macrodomains and WWE domains, functionalized by fusion to the constant "Fc" region of rabbit immunoglobulin. Herein, we present an expansion of this biological toolkit, where we have replaced the rabbit Fc sequence with the sequence from two other species, mouse and goat. These new reagents are based on a previously characterized set of naturally-occuring ARBDs with known specificity. Characterization of the new reagents demonstrates that they can be detected in a species-dependent manner by secondary immunogical tools, recognize specific ADP-ribose moieties, and can be used for simultaneous detection of MAR and PAR at single cell resolution in various antibody-based assays . The expansion of this toolkit will allow for more multiplexed assessments of the complexity of ADPRylation biology in many biological systems.

4.
Nat Mater ; 23(2): 196-204, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38191634

RESUMEN

The quest for electronic devices that offer flexibility, wearability, durability and high performance has spotlighted two-dimensional (2D) van der Waals materials as potential next-generation semiconductors. Especially noteworthy is indium selenide, which has demonstrated surprising ultra-high plasticity. To deepen our understanding of this unusual plasticity in 2D van der Waals materials and to explore inorganic plastic semiconductors, we have conducted in-depth experimental and theoretical investigations on metal monochalcogenides (MX) and transition metal dichalcogenides (MX2). We have discovered a general plastic deformation mode in MX, which is facilitated by the synergetic effect of phase transitions, interlayer gliding and micro-cracks. This is in contrast to crystals with strong atomic bonding, such as metals and ceramics, where plasticity is primarily driven by dislocations, twinning or grain boundaries. The enhancement of gliding barriers prevents macroscopic fractures through a pinning effect after changes in stacking order. The discovery of ultra-high plasticity and the phase transition mechanism in 2D MX materials holds significant potential for the design and development of high-performance inorganic plastic semiconductors.

5.
Mol Cell ; 67(2): 308-321.e6, 2017 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-28732206

RESUMEN

Enhancer activation is a critical step for gene activation. Here we report an epigenetic crosstalk at enhancers between the UTX (H3K27 demethylase)-MLL4 (H3K4 methyltransferase) complex and the histone acetyltransferase p300. We demonstrate that UTX, in a demethylase activity-independent manner, facilitates conversion of inactive enhancers in embryonic stem cells to an active (H3K4me1+/H3K27ac+) state by recruiting and coupling the enzymatic functions of MLL4 and p300. Loss of UTX leads to attenuated enhancer activity, characterized by reduced levels of H3K4me1 and H3K27ac as well as impaired transcription. The UTX-MLL4 complex enhances p300-dependent H3K27 acetylation through UTX-dependent stimulation of p300 recruitment, while MLL4-mediated H3K4 monomethylation, reciprocally, requires p300 function. Importantly, MLL4-generated H3K4me1 further enhances p300-dependent transcription. This work reveals a previously unrecognized cooperativity among enhancer-associated chromatin modulators, including a unique function for UTX, in establishing an "active enhancer landscape" and defines a detailed mechanism for the joint deposition of H3K4me1 and H3K27ac.


Asunto(s)
Cromatina/metabolismo , Proteína p300 Asociada a E1A/metabolismo , Células Madre Embrionarias/enzimología , Elementos de Facilitación Genéticos , Histona Demetilasas/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Transcripción Genética , Activación Transcripcional , Animales , Cromatina/genética , Ensamble y Desensamble de Cromatina , Proteína p300 Asociada a E1A/genética , Retroalimentación Fisiológica , Redes Reguladoras de Genes , Células HEK293 , Histona Demetilasas/genética , N-Metiltransferasa de Histona-Lisina/genética , Histonas/metabolismo , Humanos , Masculino , Metilación , Ratones , Interferencia de ARN , Transfección
6.
J Lipid Res ; 65(3): 100508, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38280458

RESUMEN

Lipid transport is an essential cellular process with importance to human health, disease development, and therapeutic strategies. Type IV P-type ATPases (P4-ATPases) have been identified as membrane lipid flippases by utilizing nitrobenzoxadiazole (NBD)-labeled lipids as substrates. Among the 14 human type IV P-type ATPases, ATP10D was shown to flip NBD-glucosylceramide (GlcCer) across the plasma membrane. Here, we found that conversion of incorporated GlcCer (d18:1/12:0) to other sphingolipids is accelerated in cells exogenously expressing ATP10D but not its ATPase-deficient mutant. These findings suggest that 1) ATP10D flips unmodified GlcCer as well as NBD-GlcCer at the plasma membrane and 2) ATP10D can translocate extracellular GlcCer, which is subsequently converted to other metabolites. Notably, exogenous expression of ATP10D led to the reduction in cellular hexosylceramide levels. Moreover, the expression of GlcCer flippases, including ATP10D, also reduced cellular hexosylceramide levels in fibroblasts derived from patients with Gaucher disease, which is a lysosomal storage disorder with excess GlcCer accumulation. Our study highlights the contribution of ATP10D to the regulation of cellular GlcCer levels and maintaining lipid homeostasis.


Asunto(s)
Glucosilceramidas , ATPasas Tipo P , Humanos , Glucosilceramidas/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Adenosina Trifosfatasas/metabolismo , Homeostasis , ATPasas Tipo P/metabolismo
7.
Cell Struct Funct ; 49(1): 1-10, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38072450

RESUMEN

Gaucher disease (GD) is a recessively inherited lysosomal storage disorder characterized by a deficiency of lysosomal glucocerebrosidase (GBA1). This deficiency results in the accumulation of its substrate, glucosylceramide (GlcCer), within lysosomes. Here, we investigated lysosomal abnormalities in fibroblasts derived from patients with GD. It is noteworthy that the cellular distribution of lysosomes and lysosomal proteolytic activity remained largely unaffected in GD fibroblasts. However, we found that lysosomal membranes of GD fibroblasts were susceptible to damage when exposed to a lysosomotropic agent. Moreover, the susceptibility of lysosomal membranes to a lysosomotropic agent could be partly restored by exogenous expression of wild-type GBA1. Here, we report that the lysosomal membrane integrity is altered in GD fibroblasts, but lysosomal distribution and proteolytic activity is not significantly altered.Key words: glucosylceramide, lysosome, Gaucher disease, lysosomotropic agent.


Asunto(s)
Enfermedad de Gaucher , Humanos , Enfermedad de Gaucher/metabolismo , Glucosilceramidas/metabolismo , Fibroblastos/metabolismo , Lisosomas/metabolismo , Membranas Intracelulares/metabolismo
8.
Small ; 20(20): e2307129, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38126615

RESUMEN

Organic luminescent materials are indispensable in optoelectronic displays and solid-state luminescence applications. Compared with single-component, multi-component crystalline materials can improve optoelectronic characteristics. This work forms a series of full-spectrum tunable luminescent charge-transfer (CT) cocrystals ranging from 400 to 800 nm through intermolecular collaborative self-assembly. What is even more interesting is that o-TCP-Cor(x)-Pe(1-x), p-TCP-Cor(x)-Pe(1-x), and o-TCP-AN(x)-TP(1-x) alloys are prepared based on cocrystals by doping strategies, which correspondingly achieve the stepless color change from blue (CIE [0.22, 0.44]) to green (CIE [0.16, 0.14]), from green (CIE [0.27, 0.56]) to orange (CIE [0.58, 0.42]), from yellow (CIE [0.40, 0.57]) to red (CIE [0.65, 0.35]). The work provides an efficient method for precisely synthesizing new luminescent organic semiconductor materials and lays a solid foundation for developing advanced organic solid-state displays.

9.
Mass Spectrom Rev ; 2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37102760

RESUMEN

Coronavirus disease 2019 (COVID-19) has emerged as a global health threat and has rapidly spread worldwide. Significant changes in the lipid profile before and after COVID-19 confirmed the significance of lipid metabolism in regulating the response to viral infection. Therefore, understanding the role of lipid metabolism may facilitate the development of new therapeutics for COVID-19. Owing to their high sensitivity and accuracy, mass spectrometry (MS)-based methods are widely used for rapidly identifying and quantifying of thousands of lipid species present in a small amount of sample. To enhance the capabilities of MS for the qualitative and quantitative analysis of lipids, different platforms have been combined to cover a wide range of lipidomes with high sensitivity, specificity, and accuracy. Currently, MS-based technologies are being established as efficient methods for discovering potential diagnostic biomarkers for COVID-19 and related diseases. As the lipidome of the host cell is drastically affected by the viral replication process, investigating lipid profile alterations in patients with COVID-19 and targeting lipid metabolism pathways are considered to be crucial steps in host-directed drug targeting to develop better therapeutic strategies. This review summarizes various MS-based strategies that have been developed for lipidomic analyzes and biomarker discoveries to combat COVID-19 by integrating various other potential approaches using different human samples. Furthermore, this review discusses the challenges in using MS technologies and future perspectives in terms of drug discovery and diagnosis of COVID-19.

10.
FASEB J ; 37(5): e22899, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37002889

RESUMEN

Sleep is a fundamental medicine for cardiac homeostasis, and sleep-deprived individuals are prone to higher incidences of heart attack. The lipid-dense diet (obesogenic diet-OBD) is a cumulative risk factor for chronic inflammation in cardiovascular disease; thus, understanding how sleep fragmentation (SF) in an obesity setting impacts immune and cardiac health is an unmet medical need. We hypothesized whether the co-existence of SF with OBD dysregulates gut homeostasis and leukocyte-derived reparative/resolution mediators, thereby impairing cardiac repair. Two-month-old male C57BL/6J mice were randomized first into two groups, then four groups; Control, control + SF, OBD, and OBD + SF mice subjected to myocardial infarction (MI). OBD mice had higher levels of plasma linolenic acid with a decrease in eicosapentaenoic and docosahexaenoic acid. The OBD mice had lower Lactobacillus johnsonii indicating a loss of probiotic microbiota. SF in OBD mice increased Firmicutes/Bacteroidetes ratio indicative of a detrimental change in SF-directed microbiome. OBD + SF group increased in the neutrophil: lymphocyte ratio suggestive of suboptimal inflammation. As a result of SF, resolution mediators (RvD2, RvD3, RvD5, LXA4 , PD1, and MaR1) decreased and inflammatory mediators (PGD2 , PGE2 , PGF2a , 6k-PGF1a ) were increased in OBD mice post-MI. At the site of infarction, the proinflammatory cytokines Ccl2, IL1ß, and IL-6 were amplified in OBD + SF indicating a robust proinflammatory milieu post-MI. Also, brain circadian genes (Bmal1, Clock) were downregulated in SF-subjected control mice, but remained elevated in OBD mice post-MI. SF superimposed on obesity dysregulated physiological inflammation and disrupted resolving response thereby impaired cardiac repair and signs of pathological inflammation.


Asunto(s)
Insuficiencia Cardíaca , Microbiota , Infarto del Miocardio , Masculino , Ratones , Animales , Privación de Sueño/complicaciones , Lipidómica , Ratones Endogámicos C57BL , Inflamación/complicaciones , Insuficiencia Cardíaca/etiología , Infarto del Miocardio/patología , Citocinas/genética , Obesidad/complicaciones
11.
Analyst ; 149(12): 3293-3301, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38713069

RESUMEN

Sphingomyelin synthase (SMS) is a sphingolipid-metabolizing enzyme involved in the de novo synthesis of sphingomyelin (SM) from ceramide (Cer). Recent studies have indicated that SMS is a key therapeutic target for metabolic diseases such as fatty liver, type 2 diabetes, atherosclerosis, and colorectal cancer. However, very few SMS inhibitors have been identified because of the limited sensitivity and selectivity of the current fluorescence-based screening assay. In this study, we developed a simple cell-based assay coupled with liquid chromatography/tandem mass spectrometry (LC-MS/MS) to screen for SMS inhibitors. HeLa cells stably expressing SMS1 or SMS2 were used for the screening. A non-fluorescent unnatural C6-Cer was used as a substrate for SMS to produce C6-SM. C6-Cer and C6-SM levels in the cells were monitored and quantified using LC-MS/MS. The activity of ginkgolic acid C15:1 (GA), a known SMS inhibitor, was measured. GA had half-maximal inhibitory concentrations of 5.5 µM and 3.6 µM for SMS1 and SMS2, respectively. To validate these findings, hSMS1 and hSMS2 proteins were optimized for molecular docking studies. In silico analyses were conducted to assess the interaction of GA with SMS1 and SMS2, and its binding affinity. This study offers an analytical approach for screening novel SMS inhibitors and provides in silico support for the experimental findings.


Asunto(s)
Espectrometría de Masas en Tándem , Transferasas (Grupos de Otros Fosfatos Sustitutos) , Humanos , Transferasas (Grupos de Otros Fosfatos Sustitutos)/metabolismo , Transferasas (Grupos de Otros Fosfatos Sustitutos)/antagonistas & inhibidores , Células HeLa , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Simulación del Acoplamiento Molecular , Inhibidores Enzimáticos/farmacología , Proteínas del Tejido Nervioso/metabolismo , Proteínas de la Membrana
12.
Microbiol Immunol ; 68(8): 281-293, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38886542

RESUMEN

The thymus, a site to culture the naïve T lymphocytes, is susceptible to atrophy or involution due to aging, inflammation, and oxidation. Epigallocatechin-3-gallate (EGCG) has been proven to possess anti-inflammatory, antioxidant, and antitumor activity. Here, we investigate the effects of EGCG on thymic involution induced by lipopolysaccharide (LPS), an endotoxin derived from Gram-negative bacteria. The methodology included an in vivo experiment on female Kunming mice exposed to LPS and EGCG. Morphological assessment of thymic involution, immunohistochemical detection, and thymocyte subsets analysis by flow cytometry were further carried out to evaluate the potential role of EGCG on the thymus. As a result, we found that EGCG alleviated LPS-induced thymic atrophy, increased mitochondrial membrane potential and superoxide dismutase levels, and decreased malondialdehyde and reactive oxygen species levels. In addition, EGCG pre-supplement restored the ratio of thymocyte subsets, the expression of autoimmune regulator, sex-determining region Y-box 2, and Nanog homebox, and reduced the number of senescent cells and collagen fiber deposition. Western blotting results indicated that EGCG treatment elevated LPS-induced decrease in pAMPK, Sirt1 protein expression. Collectively, EGCG relieved thymus architecture and function damaged by LPS via regulation of AMPK/Sirt1 signaling pathway. Our findings may provide a new strategy on protection of thymus from involution caused by LPS by using EGCG. And EGCG might be considered as a potential agent for the prevention and treatment of thymic involution.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Catequina , Lipopolisacáridos , Transducción de Señal , Sirtuina 1 , Timo , Animales , Catequina/análogos & derivados , Catequina/farmacología , Sirtuina 1/metabolismo , Ratones , Femenino , Timo/efectos de los fármacos , Timo/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Atrofia
13.
J Hered ; 115(3): 292-301, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38364316

RESUMEN

Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.


Asunto(s)
Escarabajos , Conservación de los Recursos Naturales , Genética de Población , Endogamia , Densidad de Población , Animales , Escarabajos/genética , Polimorfismo de Nucleótido Simple , Ecosistema , Flujo Génico , Genómica/métodos , Variación Genética , Biodiversidad
14.
Surg Endosc ; 38(3): 1151-1162, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38082017

RESUMEN

OBJECTIVE: To assess the effect of preoperative sarcopenia on the short-term and long-term outcomes in older patients with locally advanced gastric cancer (LAGC). METHODS: Clinicopathological data of older patients with LAGC who underwent radical surgery were retrospectively analyzed. Sarcopenia was defined as a skeletal muscle index of less than 36.4 cm2/m2 for men and less than 28.4 cm2/m2 for women. Comparing the postoperative complications and survival between sarcopenia and non-sarcopenia groups using multicenter data. RESULTS: A total of 406 older patients with LAGC were included in the analysis, including 145 (35.7%) with sarcopenia and 261 (64.3%) with non-sarcopenia. Multivariate logistic regression analysis showed that sarcopenia was an independent risk factor for postoperative complications with CD grade ≥ II (OR 1.616; P < 0.05). Kaplan-Meier survival curve analysis showed that the 5-year overall survival (OS) and 5-year recurrence-free survival (RFS) in the sarcopenia group were lower than those in the non-sarcopenia group (P both < 0.05). Multivariate Cox regression analyses showed that sarcopenia was an independent prognostic factor for 5-year OS and RFS (P both < 0.05). The 5-year recurrence rate in the sarcopenia group was 57.2%, which was significantly higher than that in the non-sarcopenia group (46.4%; P = 0.036). Recurrence pattern analysis showed that the incidence of distant metastases in patients with sarcopenia (42.8%) was significantly higher than non-sarcopenia (31.4%; P = 0.022). CONCLUSION: Sarcopenia serves as a valuable predictor of both short-term and long-term outcomes in older patients with LAGC. Therefore, the significance of assessing preoperative nutritional status and implementing thorough postoperative follow-up for older LAGC patients with sarcopenia should be emphasized.


Asunto(s)
Sarcopenia , Neoplasias Gástricas , Masculino , Humanos , Femenino , Anciano , Sarcopenia/complicaciones , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/cirugía , Estudios Retrospectivos , Pronóstico , Complicaciones Posoperatorias/etiología
15.
Appl Microbiol Biotechnol ; 108(1): 320, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709366

RESUMEN

The unspecific peroxygenase (UPO) from Cyclocybe aegerita (AaeUPO) can selectively oxidize C-H bonds using hydrogen peroxide as an oxygen donor without cofactors, which has drawn significant industrial attention. Many studies have made efforts to enhance the overall activity of AaeUPO expressed in Komagataella phaffii by employing strategies such as enzyme-directed evolution, utilizing appropriate promoters, and screening secretion peptides. Building upon these previous studies, the objective of this study was to further enhance the expression of a mutant of AaeUPO with improved activity (PaDa-I) by increasing the gene copy number, co-expressing chaperones, and optimizing culture conditions. Our results demonstrated that a strain carrying approximately three copies of expression cassettes and co-expressing the protein disulfide isomerase showed an approximately 10.7-fold increase in volumetric enzyme activity, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. After optimizing the culture conditions, the volumetric enzyme activity of this strain further increased by approximately 48.7%, reaching 117.3 U/mL. Additionally, the purified catalytic domain of PaDa-I displayed regioselective hydroxylation of R-2-phenoxypropionic acid. The results of this study may facilitate the industrial application of UPOs. KEY POINTS: • The secretion of the catalytic domain of PaDa-I can be significantly enhanced through increasing gene copy numbers and co-expressing of protein disulfide isomerase. • After optimizing the culture conditions, the volumetric enzyme activity can reach 117.3 U/mL, using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) as the substrate. • The R-2-phenoxypropionic acid can undergo the specific hydroxylation reaction catalyzed by catalytic domain of PaDa-I, resulting in the formation of R-2-(4-hydroxyphenoxy)propionic acid.


Asunto(s)
Oxigenasas de Función Mixta , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Saccharomycetales/genética , Saccharomycetales/enzimología , Saccharomycetales/metabolismo , Dosificación de Gen , Proteína Disulfuro Isomerasas/genética , Proteína Disulfuro Isomerasas/metabolismo , Expresión Génica , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química
16.
Cell Mol Biol Lett ; 29(1): 68, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730334

RESUMEN

BACKGROUND: Members of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing (NLRP) family regulate various physiological and pathological processes. However, none have been shown to regulate actin cap formation or spindle translocation during the asymmetric division of oocyte meiosis I. NLRP4E has been reported as a candidate protein in female fertility, but its function is unknown. METHODS: Immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were employed to examine the localization and expression levels of NLRP4E and related proteins in mouse oocytes. small interfering RNA (siRNA) and antibody transfection were used to knock down NLRP4E and other proteins. Immunoprecipitation (IP)-mass spectrometry was used to identify the potential proteins interacting with NLRP4E. Coimmunoprecipitation (Co-IP) was used to verify the protein interactions. Wild type (WT) or mutant NLRP4E messenger RNA (mRNA) was injected into oocytes for rescue experiments. In vitro phosphorylation was employed to examine the activation of steroid receptor coactivator (SRC) by NLRP4E. RESULTS: NLRP4E was more predominant within oocytes compared with other NLRP4 members. NLRP4E knockdown significantly inhibited actin cap formation and spindle translocation toward the cap region, resulting in the failure of polar body extrusion at the end of meiosis I. Mechanistically, GRIN1, and GANO1 activated NLRP4E by phosphorylation at Ser429 and Thr430; p-NLRP4E is translocated and is accumulated in the actin cap region during spindle translocation. Next, we found that p-NLRP4E directly phosphorylated SRC at Tyr418, while p-SRC negatively regulated p-CDC42-S71, an inactive form of CDC42 that promotes actin cap formation and spindle translocation in the GTP-bound form. CONCLUSIONS: NLRP4E activated by GRIN1 and GANO1 regulates actin cap formation and spindle translocation toward the cap region through upregulation of p-SRC-Tyr418 and downregulation of p-CDC42-S71 during meiosis I.


Asunto(s)
Actinas , Meiosis , Oocitos , Proteína de Unión al GTP cdc42 , Animales , Oocitos/metabolismo , Ratones , Femenino , Actinas/metabolismo , Actinas/genética , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP cdc42/genética , Fosforilación , Huso Acromático/metabolismo
17.
Biosci Biotechnol Biochem ; 88(5): 529-537, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38509025

RESUMEN

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.


Asunto(s)
Supervivencia Celular , Cinnamomum , Peróxido de Hidrógeno , Queratinocitos , Potencial de la Membrana Mitocondrial , Mitocondrias , Mitofagia , Estrés Oxidativo , Extractos Vegetales , Especies Reactivas de Oxígeno , Humanos , Mitofagia/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Queratinocitos/citología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Cinnamomum/química , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Adenosina Trifosfato/metabolismo , Hojas de la Planta/química , Antioxidantes/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Sirolimus/farmacología , Células HaCaT , Proteínas Quinasas/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética
18.
BMC Geriatr ; 24(1): 545, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914987

RESUMEN

BACKGROUND: Late-life depression (LLD) is a prevalent neuropsychiatric disorder in the older population. While LLD exhibits high mortality rates, depressive symptoms in older adults are often masked by physical health conditions. In younger adults, depression is associated with deficits in pupil light reflex and eye blink rate, suggesting the potential use of these responses as biomarkers for LLD. METHODS: We conducted a study using video-based eye-tracking to investigate pupil and blink responses in LLD patients (n = 25), older (OLD) healthy controls (n = 29), and younger (YOUNG) healthy controls (n = 25). The aim was to determine whether there were alterations in pupil and blink responses in LLD compared to both OLD and YOUNG groups. RESULTS: LLD patients displayed significantly higher blink rates and dampened pupil constriction responses compared to OLD and YOUNG controls. While tonic pupil size in YOUNG differed from that of OLD, LLD patients did not exhibit a significant difference compared to OLD and YOUNG controls. GDS-15 scores in older adults correlated with light and darkness reflex response variability and blink rates. PHQ-15 scores showed a correlation with blink rates, while MoCA scores correlated with tonic pupil sizes. CONCLUSIONS: The findings demonstrate that LLD patients display altered pupil and blink behavior compared to OLD and YOUNG controls. These altered responses correlated differently with the severity of depressive, somatic, and cognitive symptoms, indicating their potential as objective biomarkers for LLD.


Asunto(s)
Parpadeo , Depresión , Reflejo Pupilar , Humanos , Masculino , Anciano , Femenino , Parpadeo/fisiología , Reflejo Pupilar/fisiología , Depresión/fisiopatología , Depresión/psicología , Anciano de 80 o más Años , Persona de Mediana Edad , Adulto , Pupila/fisiología , Oscuridad , Adulto Joven , Luz
19.
Aging Clin Exp Res ; 36(1): 10, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281223

RESUMEN

BACKGROUND: Circulating metabolites (CM) play a pivotal role in our overall health, yet the current evidence concerning the involvement of diverse CM in benign prostatic hyperplasia (BPH) remains limited. Mendelian randomization (MR) offers a promising avenue to explore the potential impact of CM on BPH. METHODS: In a forward MR analysis, a cohort of 249 circulating metabolites was employed as exposures to investigate their potential associations with BPH risk. Conversely, in a reverse MR analysis, BPH was employed as an exposure to assess its effects on CM. RESULTS: The forward MR analysis discerned a linkage between six metabolites and BPH, with careful consideration to excluding heterogeneity and pleiotropy. Subsequently, the reverse MR analysis unveiled that nine metabolic compounds, mainly comprising phospholipids and triglycerides, potentially exhibit elevated levels in BPH patients. CONCLUSION: Bidirectional MR analysis furnishes genetic insight into the interplay between CM and BPH. The prominence of lipids and triglycerides emerges as significant factors intricately linked to BPH risk.


Asunto(s)
Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/genética , Hiperplasia , Análisis de la Aleatorización Mendeliana , Próstata , Triglicéridos
20.
Artículo en Inglés | MEDLINE | ID: mdl-39038343

RESUMEN

Purpose: This study aims to assess the impact of death education on college students' sense of meaning in life and ability to cope with death. Method: A questionnaire survey was conducted among a randomly selected sample of 320 undergraduate students from a specific city. The survey, administered through the paper questionnaire, collected data on students' demographic characteristics, their awareness of death, and their demand for death education. Linear regression analysis was performed to identify factors influencing the demand for death education and assess its impact on college students' attitudes towards death, sense of meaning in life, and coping abilities. Results: The results revealed that participants' personality traits and family status significantly influenced their need for death education (P < .05). The overall score for death education needs among participants was (37.40±6.57). Notably, the statement "I think death education can help me understand death" received the highest mean rating (3.85), while the statement "I think death education will help me engage in nursing work in the future" received the lowest mean rating (3.55). Personal factors such as personality, family status, being an only child, and family experiences with serious illness were found to impact college students' demand for death education (P < .05). Post-death education, significant differences were observed in scores related to death fear and escape acceptance dimensions (P < .05). Moreover, there were statistically significant improvements in students' sense of meaning in life, quality of life, and life goals following death education (P < .05). Additionally, all dimensions of death coping ability showed higher scores after death education (P < .05). Factors such as current psychological state, being an only child, family experiences with serious illness, and attendance at funerals were found to be statistically significant in relation to college students' sense of meaning in life (P < .05). Multiple regression analysis indicated that the sense of meaning in life was influenced by the current psychological state and family experiences with serious illness (P < .05). Conclusion: The study highlights the importance of integrating death education into college curriculums to address students' fear of death and enhance their appreciation of life. Providing death education can help students develop a healthier perspective on death, improve their well-being, reduce avoidance attitudes towards death-related events, and strengthen their sense of meaning in life and ability to cope with death. These findings emphasize the need for educational institutions to implement comprehensive death education programs, considering individual factors such as personality and family background, and contribute to the development of effective educational policies and curricula.

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