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1.
Int J Biol Macromol ; 275(Pt 1): 133578, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38960272

RESUMEN

Tannic acid (TA) is a natural polyphenol that shows great potential in the field of biomedicine due to its anti-inflammatory, anti-oxidant, anti-bacterial, anti-tumor, anti-virus, and neuroprotective activities. Recent studies have revealed that liquid-liquid phase separation (LLPS) is closely associated with protein aggregation. Therefore, modulating LLPS offers new insights into the treatment of neurodegenerative diseases. In this study, we investigated the influence of TA on the LLPS of the Alzheimer's-related protein tau and the underlying mechanism. Our findings indicate that TA affects the LLPS of tau in a biphasic manner, with initial promotion and subsequent suppression as the TA to tau molar ratio increases. TA modulates tau phase separation through a combination of hydrophobic interactions and hydrogen bonds. The balance between TA-tau and tau-tau interactions is found to be relevant to the material properties of TA-induced tau condensates. We further illustrate that the modulatory activity of TA in phase separation is highly dependent on the target proteins. These findings enhance our understanding of the forces driving tau LLPS under different conditions, and may facilitate the identification and optimization of compounds that can rationally modulate protein phase transition in the future.

2.
Chem Sci ; 15(26): 10065-10072, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38966375

RESUMEN

The COVID-19 pandemic caused by SARS-CoV-2 resulted in a global public health crisis. In addition to vaccines, the development of effective therapy is highly desirable. Targeting a protein that plays a critical role in virus replication may allow pan-spectrum antiviral drugs to be developed. Among SARS-CoV-2 proteins, helicase (i.e., non-structural protein 13) is considered as a promising antiviral drug target due to its highly conserved sequence, unique structure and function. Herein, we demonstrate SARS-CoV-2 helicase as a target of bismuth-based antivirals in virus-infected mammalian cells by a metal-tagged antibody approach. To search for more potent bismuth-based antivirals, we further screened a panel of bismuth compounds towards inhibition of ATPase and DNA unwinding activity of nsp13 and identified a highly potent bismuth compound Bi(5-aminotropolonate)3, namely Bi(Tro-NH2)3 with an IC50 of 30 nM for ATPase. We show that bismuth-based compounds inhibited nsp13 unwinding activity via disrupting the binding of ATP and the DNA substrate to viral helicase. Binding of Bi(iii) to nsp13 also abolished the interaction between nsp12 and nsp13 as evidenced by immunofluorescence and co-immunoprecipitation assays. Finally, we validate our in vitro data in SARS-CoV-2 infected mammalian cells. Notably, Bi(6-TG)3 exhibited an EC50 of 1.18 ± 0.09 µM with a selective index of 847 in VeroE6-TMPRSS2 infected cells. This study highlights the important role of helicase for the development of more effective antiviral drugs to combat SARS-CoV-2 infection.

3.
Mol Biol Cell ; 35(9): ar119, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39024255

RESUMEN

Hypertension affects one billion people worldwide and is the most common risk factor for cardiovascular disease, yet a comprehensive picture of its underlying genetic factors is incomplete. Amongst regulators of blood pressure is the renal outer medullary potassium (ROMK) channel. While select ROMK mutants are prone to premature degradation and lead to disease, heterozygous carriers of some of these same alleles are protected from hypertension. Therefore, we hypothesized that gain-of-function (GoF) ROMK variants which increase potassium flux may predispose people to hypertension. To begin to test this hypothesis, we employed genetic screens and a candidate-based approach to identify six GoF variants in yeast. Subsequent functional assays in higher cells revealed two variant classes. The first group exhibited greater stability in the endoplasmic reticulum, enhanced channel assembly, and/or increased protein at the cell surface. The second group of variants resided in the PIP2-binding pocket, and computational modeling coupled with patch-clamp studies demonstrated lower free energy for channel opening and slowed current rundown, consistent with an acquired PIP2-activated state. Together, these findings advance our understanding of ROMK structure-function, suggest the existence of hyperactive ROMK alleles in humans, and establish a system to facilitate the development of ROMK-targeted antihypertensives.


Asunto(s)
Canales de Potasio de Rectificación Interna , Humanos , Canales de Potasio de Rectificación Interna/metabolismo , Canales de Potasio de Rectificación Interna/genética , Mutación con Ganancia de Función , Potasio/metabolismo , Hipertensión/genética , Hipertensión/metabolismo , Riñón/metabolismo , Mutación/genética , Células HEK293 , Retículo Endoplásmico/metabolismo , Transporte Iónico , Alelos
4.
Front Immunol ; 15: 1405318, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055715

RESUMEN

Human papilloma virus (HPV) is an etiological factor of head and neck squamous cell carcinoma (HNSCC). To investigate the role of HPV antigen in anti-tumor immunity, we established mouse models by expressing HPV16 E6 and E7 in a SCC tumor cell line. We obtained two HPV antigen-expressing clones (C-225 and C-100) transplantable into C57BL/6 recipients. We found that C-225 elicited complete eradication in C57BL/6 mice (eradicated), whereas C-100 grew progressively (growing). We examined immune tumor microenvironment (TME) using flow cytometry and found that eradicated or growing tumors exhibited differential immune profiles that may influence the outcome of anti-tumor immunity. Surprisingly, the percentage of CD8 and CD4 tumor-infiltrating lymphocytes (TILs) was much higher in growing (C-100) than eradicated (C-225) tumor. However, the TILs upregulated PD-1 and LAG-3 more potently and exhibited impaired effector functions in growing tumor compared to their counterparts in eradicated tumor. C-225 TME is highly enriched with myeloid cells, especially polymorphonuclear (PMN) myeloid-derived suppressor cells (MDSC), whereas the percentage of M-MDSC and tumor-associated macrophages (TAMs) was much higher in C-100 TME, especially M2-TAMs (CD206+). The complete eradication of C-225 depended on CD8 T cells and elicited anti-tumor memory responses upon secondary tumor challenge. We employed DNA sequencing to identify differences in the T cell receptor of peripheral blood lymphocytes pre- and post-secondary tumor challenge. Lastly, C-225 and C-100 tumor lines harbored different somatic mutations. Overall, we uncovered differential immune TME that may underlie the divergent outcomes of anti-tumor immunity by establishing two SCC tumor lines, both of which express HPV16 E6 and E7 antigens. Our experimental models may provide a platform for pinpointing tumor-intrinsic versus host-intrinsic differences in orchestrating an immunosuppressive TME in HNSCCs and for identifying new targets that render tumor cells vulnerable to immune attack.


Asunto(s)
Modelos Animales de Enfermedad , Linfocitos Infiltrantes de Tumor , Ratones Endogámicos C57BL , Proteínas Oncogénicas Virales , Proteínas E7 de Papillomavirus , Infecciones por Papillomavirus , Microambiente Tumoral , Animales , Microambiente Tumoral/inmunología , Ratones , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Línea Celular Tumoral , Proteínas Oncogénicas Virales/inmunología , Proteínas Oncogénicas Virales/genética , Proteínas E7 de Papillomavirus/inmunología , Proteínas E7 de Papillomavirus/genética , Infecciones por Papillomavirus/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Proteínas Represoras/genética , Proteína del Gen 3 de Activación de Linfocitos , Humanos , Progresión de la Enfermedad , Linfocitos T CD8-positivos/inmunología , Receptor de Muerte Celular Programada 1 , Femenino , Papillomavirus Humano 16/inmunología , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias de Cabeza y Cuello/virología
5.
J Sci Food Agric ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38872574

RESUMEN

BACKGROUND: The effect of oleogels prepared with peanut oil and different concentrations of γ-oryzanol and ß-sitosterol mixture (γ/ß; 20, 40, 60, 80 and 100 g kg-1) on the physicochemical and gel properties of myofibrillar protein (MP) was investigated. RESULTS: The solubility and average particle size of MP first decreased and then increased with increasing γ/ß concentration. Peanut oil or oleogels could induce the exposure of hydrophobic amino acids and the unfolding of MP, thus significantly increasing the surface hydrophobicity, sulfhydryl content and absolute value of zeta potential, which reached maximum values when the γ/ß concentration was 60 g kg-1 (P < 0.05). The addition of peanut oil decreased the gel strength and water holding capacity of MP gel. However, oleogels prepared with 60 g kg-1 γ/ß could significantly increase the hydrophobic interactions and disulfide bond content of MP gel (P < 0.05), which promoted the crosslinking and aggregation of MP, enhancing the gel properties. Peanut oil had no significant influence on the secondary structure of MP, while oleogels promoted the transition of MP conformation from α-helix to ß-sheet structure. The results of light microscopy and confocal laser scanning microscopy indicated that oleogels prepared with 60 g kg-1 γ/ß filled in the pores of MP gel network to form denser and more uniform structure. CONCLUSION: Oleogels prepared with 60 g kg-1 γ/ß could effectively improve the quality of MP gel and have promising application prospects in surimi products. © 2024 Society of Chemical Industry.

6.
Food Res Int ; 188: 114532, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823889

RESUMEN

Luteolin has anti-inflammatory, antioxidant, and anti-tumor functions, but its poor water solubility and stability limit its applications in foods as a functional component. In this study, the nanocomposites loading luteolin (Lut) with soybean protein isolate (SPI), soluble soybean polysaccharide (SSPS) and/or rhamnolipid (Rha) were prepared by layer-by-layer shelf assembly method, and their properties were also evaluated. The results showed that Rha/SPI/Lut had the smallest particle size (206.24 nm) and highest loading ratio (8.03 µg/mg) while Rha/SSPS/SPI/Lut had the highest encapsulation efficiency (82.45 %). Rha interacted with SPI through hydrophobic interactions as the main driving force, while SSPS attached to SPI with only hydrogen bonding. Furthermore, the synergistic effect between Rha and SSPS was observed in Rha/SSPS/SPI/Lut complex, in consequence, it had the best thermal and storage stability, and the slowest release in gastrointestinal digestion. Thus, this approach provided an alternative way for the application of luteolin in functional foods.


Asunto(s)
Digestión , Luteolina , Tamaño de la Partícula , Proteínas de Soja , Luteolina/química , Proteínas de Soja/química , Nanocompuestos/química , Polisacáridos/química , Interacciones Hidrofóbicas e Hidrofílicas , Glycine max/química , Solubilidad , Alimentos Funcionales , Tracto Gastrointestinal/metabolismo
7.
Food Chem ; 455: 139841, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38824724

RESUMEN

Microcrystalline cellulose was modified by TEMPO oxidation combined with ultrasound to prepare modified cellulose-based emulsion. The effect of different emulsion concentration on gel properties and protein conformation of surimi was investigated. The results showed the length and width of microcrystalline cellulose were reduced, and a large amount of -COOH was introduced into modified cellulose. Direct addition of flaxseed oil decreased the gel strength and WHC from 3640.49 g·mm and 76.94% to 2702.95 g·mm and 75.89%, respectively, while 5% modified cellulose-based emulsion could improve the gel properties of surimi. Surimi gel containing 5% emulsion had the highest hydrophobic interaction, disulfide bond and ß-sheet content. Moreover, protein network structure was the densest in 5% emulsion group. Therefore, modified cellulose-based emulsion could be used to compensating for the negative impact of direct addition of flaxseed oil on surimi, which provided a new idea for the development of healthy and new emulsified surimi products.


Asunto(s)
Celulosa , Emulsiones , Productos Pesqueros , Geles , Celulosa/química , Emulsiones/química , Animales , Geles/química , Productos Pesqueros/análisis , Conformación Proteica , Proteínas de Peces/química , Interacciones Hidrofóbicas e Hidrofílicas
8.
Bioorg Chem ; 148: 107438, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761703

RESUMEN

The synergism of host Paris polyphylla medium, the monoculture, and the coculture led to seventeen new metabolites, including eight sesquiterpenes, 1-7 having uncommon structural motifs compared to similar caryophyllene derivatives, 8 with an unprecedented bicyclic framework, and three xyloketals (13-15) with unprecedented frameworks from Nigrospora lacticolonia; one polyketide, 17 with novel bicyclo [2.2.2] undecane skeleton, and five polyketide-terpenoid hybrids, 20 (one novel sulfated), 21-24 from Penicillium rubens. The structures were determined mainly by the NMR, HRESIMS, ECD calculation, and single-crystal X-ray diffraction. Nine cryptic compounds (2-4, 5, 12-15, 17) were produced by the inductions of host medium and the coculture. The compounds 13 from N. lacticolonia, 24-26, 28, 29, and 31 from P. rubens indicated significant antiphytopathogenic activities against N. lacticolonia with MICs at 2-4 µg/mL. Moreover, compounds 22-26, 28, 29, and 31 from P. rubens showed antifungal activities against P. rubens with MICs at 2-4 µg/mL. The synergistic effects of host medium and the coculture can induce the structural diversity of metabolites.


Asunto(s)
Técnicas de Cocultivo , Penicillium , Penicillium/química , Penicillium/metabolismo , Penicillium/efectos de los fármacos , Estructura Molecular , Ascomicetos/efectos de los fármacos , Ascomicetos/química , Ascomicetos/metabolismo , Relación Estructura-Actividad , Antifúngicos/farmacología , Antifúngicos/química , Pruebas de Sensibilidad Microbiana , Relación Dosis-Respuesta a Droga
9.
Int J Biol Macromol ; 268(Pt 1): 131699, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642689

RESUMEN

Starch and peanut oil (PO) were widely used to improve the gel properties of surimi, however, the impact mechanism of addition forms on the denaturation and aggregation behavior of myofibrillar protein (MP) is not clear. Therefore, the effect of starch, PO, starch/PO mixture, and starch-based emulsion on the physicochemical and gel properties of MP was investigated. The results showed that amylose could accelerate the aggregation of MP, while amylopectin was conducive to the improvement of gel properties. The addition of PO, starch/PO mixture, or starch-based emulsion increased the turbidity, solubility, sulfhydryl content of MP, and improved the gel strength, whiteness, and texture of MP gel. However, compared with starch/PO mixture group, the gel strength of MP with waxy, normal and high amylose corn starch-based emulsion increased by 22.68 %, 10.27 %, and 32.89 %, respectively. The MP containing emulsion had higher storage modulus than MP with starch/PO mixture under the same amylose content. CLSM results indicated that the oil droplets aggregated in PO or starch/PO mixture group, while emulsified oil droplets filled the protein gel network more homogeneously. Therefore, the addition of starch and PO in the form of emulsion could effectively play the filling role to improve the gel properties of MP.


Asunto(s)
Amilosa , Emulsiones , Geles , Aceite de Cacahuete , Almidón , Amilosa/química , Amilosa/análisis , Aceite de Cacahuete/química , Almidón/química , Geles/química , Emulsiones/química , Proteínas Musculares/química , Fenómenos Químicos , Solubilidad , Miofibrillas/química
10.
Food Chem ; 446: 138903, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38452507

RESUMEN

Cryoprotective effect and potential mechanism of soluble soybean polysaccharides (SSPS) and enzymatic hydrolysates on surimi was investigated. After hydrolysis, the molecular weight of SSPS significantly decreased, and the hydrolysates prepared by endo-polygalacturonase (EPG-SSPS) was the lowest (154 kDa). Infrared spectrum analysis revealed that enzymatic hydrolysis didn't alter the functional groups of SSPS, but it did augment the exposure to hydroxyl groups. Surimi containing 5 % EPG-SSPS had the lowest freezable water after 20 days of frozen storage. Furthermore, the 5 % EPG-SSPS group manifested the highest metrics in total sulfhydryl (8.0 × 10-5 mol/g), active sulfhydryl content (6.7 × 10-5 mol/g), Ca2+-ATPase activity, and exhibited the lowest level in carbonyl content, surface hydrophobicity (153 µg). Notably, the 5 % EPG-SSPS maintained the stability of protein structure. Conclusively, SSPS enzymatic hydrolysate using endo-polygalacturonase imparted superior cryoprotective effect on the myofibrillar protein of surimi, and the mechanism might be a decrease in molecular weight and exposure of hydroxyl groups.


Asunto(s)
Crioprotectores , Glycine max , Animales , Crioprotectores/química , Poligalacturonasa , Polisacáridos/farmacología , Polisacáridos/química , Congelación , Peces , Hidrolisados de Proteína/química
11.
Fish Physiol Biochem ; 50(3): 927-939, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38305929

RESUMEN

Temperature fluctuations are inevitable and have an important impact on the survival of fish during transportation. Therefore, the effect of temperature fluctuation (15 ± 1 °C, 15 ± 2 °C, 15 ± 3 °C) on the muscle quality, physiological, and immune function of hybrid pearl gentian grouper before waterless keeping alive, during keeping alive (0 h, 3 h, 6 h, 9 h, 12 h), and after revival for 12 h was investigated. The plasma glucose concentration of grouper gradually decreased to 0.645 ± 0.007 mg/mL, 0.657 ± 0.006 mg/mL, and 0.677 ± 0.004 mg/mL after keeping alive for 12 h under different temperature fluctuations of 15 ± 1 °C, 15 ± 2 °C, and 15 ± 3 °C, respectively. The cortisol concentration and lysozyme activity of pearl gentian grouper significantly increased (P < 0.05) during the keeping alive period. The results suggested that fish bodies would produce acute stress response, strengthen immune defense ability, and quickly consume a lot of energy to adapt to the low-temperature anhydrous environment. In all treatment groups, the activities of plasma alanine transaminase (ALT) and aspartate aminotransferase (AST) and the content of creatinine gradually increased with the prolongation of the survival time. The hardness and springiness of muscle decreased from 5965.99 ± 20.15 and 0.90 ± 0.00 to 3490.69 ± 27.59 and 0.42 ± 0.01, respectively. In the meanwhile, the change of glycogen and lactic acid content was opposite, indicating that temperature fluctuation harmed the liver, kidney function, and muscle quality. In the later stage of keeping alive, the superoxide dismutase (SOD) and catalase (CAT) activities decreased, especially in the temperature fluctuation group of ±3 °C (125.99 ± 5.48 U/mgprot, 44.21 ± 0.63 U/mgprot), leading to an imbalance of fish immunity. In summary, higher temperature fluctuation would influence the physiological function and immune defense ability and decrease the quality of pearl gentian grouper.


Asunto(s)
Estrés Fisiológico , Temperatura , Animales , Hidrocortisona/sangre , Glucemia , Lubina/fisiología , Muramidasa/sangre , Muramidasa/metabolismo , Aspartato Aminotransferasas/sangre , Alanina Transaminasa/sangre , Músculos/metabolismo , Creatinina/sangre
12.
J Physiol ; 602(4): 737-757, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38345534

RESUMEN

Paraoxonase 3 (PON3) is expressed in the aldosterone-sensitive distal nephron, where filtered Na+ is reabsorbed mainly via the epithelial Na+ channel (ENaC) and Na+ -coupled co-transporters. We previously showed that PON3 negatively regulates ENaC through a chaperone mechanism. The present study aimed to determine the physiological role of PON3 in renal Na+ and K+ homeostasis. Pon3 knockout (KO) mice had higher amiloride-induced natriuresis and lower plasma [K+ ] at baseline. Single channel recordings in split-open tubules showed that the number of active channels per patch was significantly higher in KO mice, resulting in a higher channel activity in the absence of PON3. Although whole kidney abundance of ENaC subunits was not altered in Pon3 KOs, ENaC gamma subunit was more apically distributed within the connecting tubules and cortical collecting ducts of Pon3 KO kidneys. Additionally, small interfering RNA-mediated knockdown of PON3 in cultured mouse cortical collecting duct cells led to an increased surface abundance of ENaC gamma subunit. As a result of lower plasma [K+ ], sodium chloride co-transporter phosphorylation was enhanced in the KO kidneys, a phenotype that was corrected by a high K+ diet. Finally, PON3 expression was upregulated in mouse kidneys under dietary K+ restriction, potentially providing a mechanism to dampen ENaC activity and associated K+ secretion. Taken together, our results show that PON3 has a role in renal Na+ and K+ homeostasis through regulating ENaC functional expression in the distal nephron. KEY POINTS: Paraoxonase 3 (PON3) is expressed in the distal nephron of mouse kidneys and functions as a molecular chaperone to reduce epithelial Na+ channel (ENaC) expression and activity in heterologous expression systems. We examined the physiological role of PON3 in renal Na+ and K+ handling using a Pon3 knockout (KO) mouse model. At baseline, Pon3 KO mice had lower blood [K+ ], more functional ENaC in connecting tubules/cortical collecting ducts, higher amiloride-induced natriuresis, and enhanced sodium chloride co-transporter (NCC) phosphorylation. Upon challenge with a high K+ diet, Pon3 KO mice had normalized blood [K+ ] and -NCC phosphorylation but lower circulating aldosterone levels compared to their littermate controls. Kidney PON3 abundance was altered in mice under dietary K+ loading or K+ restriction, providing a potential mechanism for regulating ENaC functional expression and renal Na+ and K+ homeostasis in the distal nephron.


Asunto(s)
Amilorida , Simportadores , Ratones , Animales , Amilorida/farmacología , Arildialquilfosfatasa/metabolismo , Canales Epiteliales de Sodio/metabolismo , Aldosterona/metabolismo , Cloruro de Sodio/metabolismo , Sodio/metabolismo , Nefronas/metabolismo
13.
Int J Biol Macromol ; 259(Pt 1): 129183, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38176498

RESUMEN

The emulsion was prepared with peanut oil and corn starch with different amylose content using high-speed homogenization assisted high-pressure homogenization, and the effect of starch-based emulsion on the gel properties, whiteness, microstructure, protein secondary structure, chemical forces, texture and sensory properties of Nemipterus virgatus surimi was investigated. The results showed that high amylose corn starch was more beneficial to the stability of emulsion than normal and waxy starch. The gel strength, water holding capacity and texture properties of surimi were significantly improved by adding 10 % waxy corn starch-based emulsion or 15 % high amylose or normal corn starch-based emulsion. Moreover, the whiteness of surimi gel containing starch-based emulsion was higher, and the microstructure was more compact and delicate than that of surimi without emulsion. The addition of starch-based emulsion could increase the hydrophobic interaction and disulfide bond content, and promote the transformation of protein secondary structure to irregular direction. The sensory properties such as color, texture, taste and overall acceptability could be improved to varying degrees. Therefore, starch-based emulsion could be used to enhance the gel properties and nutritional value of surimi products.


Asunto(s)
Amilosa , Almidón , Animales , Amilosa/química , Almidón/química , Emulsiones , Geles/química , Peces , Amilopectina
14.
Hum Brain Mapp ; 45(1): e26552, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38050776

RESUMEN

Electroencephalography (EEG) microstate analysis has become a popular tool for studying the spatial and temporal dynamics of large-scale electrophysiological activities in the brain in recent years. Four canonical topographies of the electric field (classes A, B, C, and D) have been widely identified, and changes in microstate parameters are associated with several psychiatric disorders and cognitive functions. Recent studies have reported the modulation of EEG microstate by mental workload (MWL). However, the common practice of evaluating MWL is in a specific task. Whether the modulation of microstate by MWL is consistent across different types of tasks is still not clear. Here, we studied the topographies and dynamics of microstate in two independent MWL tasks: NBack and the multi-attribute task battery (MATB) and showed that the modulation of MWL on microstate topographies and parameters depended on tasks. We found that the parameters of microstates A and C, and the topographies of microstates A, B, and D were significantly different between the two tasks. Meanwhile, all four microstate topographies and parameters of microstates A and C were different during the NBack task, but no significant difference was found during the MATB task. Furthermore, we employed a support vector machine recursive feature elimination procedure to investigate whether microstate parameters were suitable for MWL classification. An averaged classification accuracy of 87% for within-task and 78% for cross-task MWL discrimination was achieved with at least 10 features. Collectively, our findings suggest that topographies and parameters of microstates can provide valuable information about neural activity patterns with a dynamic temporal structure at different levels of MWL, but the modulation of MWL depends on tasks and their corresponding functional systems. Moreover, as a potential indicator, microstate parameters could be used to distinguish MWL.


Asunto(s)
Electroencefalografía , Trastornos Mentales , Humanos , Electroencefalografía/métodos , Encéfalo/fisiología , Mapeo Encefálico/métodos , Cognición
15.
ACS Infect Dis ; 10(3): 858-869, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-37897418

RESUMEN

SARS-CoV-2 nsp14 functions both as an exoribonuclease (ExoN) together with its critical cofactor nsp10 and as an S-adenosyl methionine-dependent (guanine-N7) methyltransferase (MTase), which makes it an attractive target for the development of pan-anti-SARS-CoV-2 drugs. Herein, we screened a panel of compounds (and drugs) and found that certain compounds, especially Bi(III)-based compounds, could allosterically inhibit both MTase and ExoN activities of nsp14 potently. We further demonstrated that Bi(III) binds to both nsp14 and nsp10, resulting in the release of Zn(II) ions from the enzymes as well as alternation of protein quaternary structures. The in vitro activities of the compounds were also validated in SARS-CoV-2-infected mammalian cells. Importantly, we showed that nsp14 serves as an authentic target of Bi(III)-based antivirals in SARS-CoV-2-infected mammalian cells by quantification of both the protein and inhibitor. This study highlights the importance of nsp14/nsp10 as a potential target for the development of pan-antivirals against SARS-CoV-2 infection.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , SARS-CoV-2/metabolismo , Proteínas no Estructurales Virales/metabolismo , Metiltransferasas/metabolismo , S-Adenosilmetionina/química , S-Adenosilmetionina/metabolismo , Antivirales/farmacología , Mamíferos/metabolismo
16.
J Agric Food Chem ; 72(1): 378-389, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38156646

RESUMEN

The antagonistic coculture with tea phytopathogen Colletotrichum pseudomajus induces antifungal cryptic metabolites from isogenesis endophyte Daldinia eschscholtzii against tea phytopathogens. Sixteen new polyketides with six structural frameworks including ten cryptic ones, named coldaldols A-C (1-3), collediol (5), and daldinrins A-L (10-20 and 23), were found from the coculture of C. pseudomajus and D. eschscholtzii by different culture methods. The unique framework of compounds 11 and 12 featured a benzopyran-C7 polyketone hybrid, and compounds 13-16 were characterized by the novel benzopyran dimer. The structures were determined mainly by spectroscopic methods, including extensive one-dimensional (1D), two-dimensional (2D) NMR, high resolution electrospray ionisation mass spectroscopy (HRESIMS), ECD calculation, and single-crystal X-ray diffraction. The configuration of acyclic compounds 5 and 18 were determined by application of the universal NMR database. Most compounds showed significant antifungal activities against the tea pathogens C. pseudomajus and Alternaria sp. with MICs of 1-8 µg/mL. Compound 12 had stronger antifungal activity than that of positive drug nystatin. The ether bond at C-4 of the benzopyran derivative increased the antifungal activity. Compounds 4-9 and 11-23 showed antifeedant activities against silkworms with feeding deterrence indices of 15-100% at the concentration of 50 µg/cm2.


Asunto(s)
Colletotrichum , Policétidos , Antifúngicos/química , Endófitos/metabolismo , Técnicas de Cocultivo , Policétidos/farmacología , Policétidos/química , Colletotrichum/metabolismo , Espectroscopía de Resonancia Magnética , Benzopiranos ,
17.
Cell Death Dis ; 14(9): 599, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37679334

RESUMEN

Deletion of TRAF2 or TRAF3 in B cells prolongs their survival. However, it remains unknown whether deletion of such factors affects B cells' ability to tolerate DNA damage, which can be induced by chemotherapeutics and cause apoptosis. Genetic alterations of TRAF2 or TRAF3 are observed in subsets of human B-cell lymphomas and B cell-specific deletion of TRAF3 led to lymphoma development in aged mice. However, it remains unknown whether double deficiency of TRAF2 and TRAF3 accelerates B-cell lymphomagenesis. Here, we showed that B cell-specific TRAF2/3 double deficient (B-TRAF2/3-DKO) B cells were remarkably more resistant to DNA damage-induced apoptosis via upregulating cIAP2 and XIAP, which in turn attenuates caspase-3 activation. Mechanistically, resistance to DNA damage-induced apoptosis required NF-κB2, which effects by upregulating XIAP and cIAP2 transcription. B-TRAF2/3-DKO mice exhibited a shorter lifespan and succumbed to splenomegaly and lymphadenopathy. Unexpectedly, the incidence of B-cell lymphoma development in B-TRAF2/3-DKO mice was relatively rare (∼10%). Sequencing B cell receptor repertoire of diseased B cells revealed that TRAF2/3 deficiency caused abnormal oligoclonal or clonal expansion of B cells. While a fraction of mutant B cells (25-43%) from aged diseased mice harbored recurrent chromosomal translocations, primary B cells isolated from young B-TRAF2/3-DKO mice had no detectable chromosomal alterations, suggesting that TRAF2/3 deficiency per se does not cause evident genomic instability in B cells. Chemo-resistant TRAF3-deficient B-cell lymphomas were sensitized to chemotherapeutic drugs by blocking IAP activity using IAP antagonist. We conclude that double deficiency of TRAF2 and TRAF3 does not accelerate B-cell lymphomagenesis. Our studies provide insight into mechanisms regulating DNA damage-induced apoptosis and may help develop effective therapies targeting mutant B-cell lymphomas using IAP antagonist.


Asunto(s)
Linfoma de Células B , Linfoma , Humanos , Animales , Ratones , Anciano , Factor 2 Asociado a Receptor de TNF/genética , Factor 3 Asociado a Receptor de TNF/genética , Subunidad p52 de NF-kappa B , Apoptosis/genética , Daño del ADN , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/genética , Proteína Inhibidora de la Apoptosis Ligada a X
18.
Micromachines (Basel) ; 14(9)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37763860

RESUMEN

The research on the remote control of manipulators based on flexible sensor technology is gradually extensive. In order to achieve stable, accurate, and efficient control of the manipulator, it is necessary to reasonably design the structure of the sensor with excellent tensile strength and flexibility. The acquisition of manual information by high-performance sensors is the basis of manipulator control. This paper starts with the manufacturing of materials of the flexible sensor for the manipulator, introduces the substrate, sensor, and flexible electrode materials, respectively, and summarizes the performance of different flexible sensors. From the perspective of manufacturing, it introduces their basic principles and compares their advantages and disadvantages. Then, according to the different ways of wearing, the two control methods of data glove control and surface EMG control are respectively introduced, the principle, control process, and detection accuracy are summarized, and the problems of material microstructure, reducing the cost, optimizing the circuit design and so on are emphasized in this field. Finally, the commercial application in this field is explained and the future research direction is proposed from two aspects: how to ensure real-time control and better receive the feedback signal from the manipulator.

19.
Neurobiol Dis ; 183: 106167, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37230179

RESUMEN

The past 15 years have witnessed an explosion in the studies of biomolecular condensates that are implicated in numerous biological processes and play vital roles in human health and diseases. Recent findings demonstrate that the microtubule-associated protein tau forms liquid condensates through liquid-liquid phase separation (LLPS) in in vitro experiments using purified recombinant proteins and cell-based experiments. Although in vivo studies are lacking, liquid condensates have emerged as an important assembly state of physiological and pathological tau and LLPS can regulate the function of microtubules, mediate stress granule formation, and accelerate tau amyloid aggregation. In this review, we summarize recent advances in tau LLPS, aiming to unveiling the delicate interactions driving tau LLPS. We further discuss the association of tau LLPS with physiology and disease in the context of the sophisticated regulation of tau LLPS. Deciphering the mechanisms underlying tau LLPS and the liquid-to-solid transition enables rational design of molecules that inhibit or delay the formation of tau solid species, thus providing novel targeted therapeutic strategies for tauopathies.


Asunto(s)
Tauopatías , Proteínas tau , Humanos , Proteínas tau/metabolismo , Proteínas Recombinantes , Amiloide , Proteínas Amiloidogénicas
20.
Food Funct ; 14(10): 4552-4568, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37021634

RESUMEN

This study aimed to investigate the potential neuroprotective effects of Lycium ruthenicum polyphenols (LRP) against acrylamide (ACR)-induced neurotoxicity and the mechanism of action in vitro and in vivo. LRP treatment significantly attenuated ACR-induced cytotoxicity in SH-SY5Y cells in a dose-dependent manner. LRP treatment increased the nuclear factor erythroid-2-related factor 2 (Nrf2) protein and subsequent activation of downstream proteins in SH-SY5Y cells. LRP treatment down-regulated the expression of relevant apoptotic proteins, including JNK, P-JNK, P38, P-P38, and caspase 3 in ACR-induced cells. In vivo, LRP improved exploratory and locomotor deficits in ACR-induced rats. LRP activated the Nrf2 pathway in the striatum and substantia nigra. LRP treatment attenuated striatal ROS levels and increased GSH and SOD in ACR-induced rats. Immunohistochemistry, western blot, and ELISA revealed a significant increase in tyrosine hydroxylase (TH) neurons and dopamine and its metabolites in the striatum and substantia nigra under the protective effect of LRP. Therefore, LRP can be a protective agent against ACR-induced brain damage.


Asunto(s)
Lycium , Neuroblastoma , Fármacos Neuroprotectores , Síndromes de Neurotoxicidad , Ratas , Humanos , Animales , Lycium/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Acrilamida/toxicidad , Síndromes de Neurotoxicidad/tratamiento farmacológico , Síndromes de Neurotoxicidad/etiología , Fármacos Neuroprotectores/farmacología
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