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1.
Food Res Int ; 188: 114531, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823850

RESUMO

Different emulsion gel systems are widely applied to deliver functional ingredients. The effects and mechanisms of ultrasound-assisted emulsification (UAE) treatment and carboxymethyl cellulose (CMC) modifying the curcumin delivery properties and in vitro digestibility of the myofibrillar protein (MP)-soybean oil emulsion gels were investigated. The rheological properties, droplet size, protein and CMC distribution, ultrastructure, surface hydrophobicity, sulfhydryl groups, and zeta potential of emulsion gels were also measured. Results indicate that UAE treatment and CMC addition both improved curcumin encapsulation and protection efficiency in MP emulsion gel, especially for the UAE combined with CMC (UAE-CMC) treatment which encapsulation efficiency, protection efficiency, the release rate, and bioaccessibility of curcumin increased from 86.75 % to 97.67 %, 44.85 % to 68.85 %, 18.44 % to 41.78 %, and 28.68 % to 44.93 % respectively. The protein digestibility during the gastric stage was decreased after the CMC addition and UAE treatment, and the protein digestibility during the intestinal stage was reduced after the CMC addition. The fatty acid release rate was increased after CMC addition and UAE treatment. Apparent viscosity, storage modulus, and loss modulus were decreased after CMC addition while increased after UAE and UAE-CMC treatment especially the storage modulus increased from 0.26 Pa to 41 Pa after UAE-CMC treatment. The oil size was decreased, the protein and CMC concentration around the oil was increased, and a denser and uniform emulsion gel network structure was formed after UAE treatment. The surface hydrophobicity, free SH groups, and absolute zeta potential were increased after UAE treatment. The UAE-CMC treatment could strengthen the MP emulsion gel structure and decrease the oil size to increase the curcumin delivery properties, and hydrophobic and electrostatic interaction might be essential forces to maintain the emulsion gel.


Assuntos
Carboximetilcelulose Sódica , Curcumina , Digestão , Emulsões , Géis , Interações Hidrofóbicas e Hidrofílicas , Reologia , Curcumina/química , Emulsões/química , Carboximetilcelulose Sódica/química , Géis/química , Proteínas Musculares , Óleo de Soja/química , Viscosidade , Tamanho da Partícula , Miofibrilas/química , Miofibrilas/metabolismo , Ondas Ultrassônicas
2.
Plant Commun ; 5(6): 100852, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38409783

RESUMO

Climate change is resulting in more frequent and rapidly changing temperatures at both extremes that severely affect the growth and production of plants, particularly crops. Oxidative stress caused by high temperatures is one of the most damaging factors for plants. However, the role of hydrogen peroxide (H2O2) in modulating plant thermotolerance is largely unknown, and the regulation of photorespiration essential for C3 species remains to be fully clarified. Here, we report that heat stress promotes H2O2 accumulation in chloroplasts and that H2O2 stimulates sulfenylation of the chloroplast-localized photorespiratory enzyme 2-phosphoglycolate phosphatase 1 (PGLP1) at cysteine 86, inhibiting its activity and promoting the accumulation of the toxic metabolite 2-phosphoglycolate. We also demonstrate that PGLP1 has a positive function in plant thermotolerance, as PGLP1 antisense lines have greater heat sensitivity and PGLP1-overexpressing plants have higher heat-stress tolerance than the wild type. Together, our results demonstrate that heat-induced H2O2 in chloroplasts sulfenylates and inhibits PGLP1 to modulate plant thermotolerance. Furthermore, targeting CATALASE2 to chloroplasts can largely prevent the heat-induced overaccumulation of H2O2 and the sulfenylation of PGLP1, thus conferring thermotolerance without a plant growth penalty. These findings reveal that heat-induced H2O2 in chloroplasts is important for heat-caused plant damage.


Assuntos
Peróxido de Hidrogênio , Termotolerância , Peróxido de Hidrogênio/metabolismo , Termotolerância/efeitos dos fármacos , Termotolerância/genética , Cloroplastos/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/fisiologia , Arabidopsis/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética , Temperatura Alta , Resposta ao Choque Térmico/efeitos dos fármacos
3.
Mol Plant ; 17(2): 325-341, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-38178576

RESUMO

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial blight (BB), a globally devastating disease of rice (Oryza sativa) that is responsible for significant crop loss. Sugars and sugar metabolites are important for pathogen infection, providing energy and regulating events associated with defense responses; however, the mechanisms by which they regulate such events in BB are unclear. As an inevitable sugar metabolite, methylglyoxal (MG) is involved in plant growth and responses to various abiotic stresses, but the underlying mechanisms remain enigmatic. Whether and how MG functions in plant biotic stress responses is almost completely unknown. Here, we report that the Xoo strain PXO99 induces OsWRKY62.1 to repress transcription of OsGLY II genes by directly binding to their promoters, resulting in overaccumulation of MG. MG negatively regulates rice resistance against PXO99: osglyII2 mutants with higher MG levels are more susceptible to the pathogen, whereas OsGLYII2-overexpressing plants with lower MG content show greater resistance than the wild type. Overexpression of OsGLYII2 to prevent excessive MG accumulation confers broad-spectrum resistance against the biotrophic bacterial pathogens Xoo and Xanthomonas oryzae pv. oryzicola and the necrotrophic fungal pathogen Rhizoctonia solani, which causes rice sheath blight. Further evidence shows that MG reduces rice resistance against PXO99 through CONSTITUTIVE DISEASE RESISTANCE 1 (OsCDR1). MG modifies the Arg97 residue of OsCDR1 to inhibit its aspartic protease activity, which is essential for OsCDR1-enhanced immunity. Taken together, these findings illustrate how Xoo promotes infection by hijacking a sugar metabolite in the host plant.


Assuntos
Oryza , Xanthomonas , Oryza/genética , Proteínas de Plantas/metabolismo , Aldeído Pirúvico/metabolismo , Xanthomonas/fisiologia , Resistência à Doença/genética , Açúcares/metabolismo , Peptídeo Hidrolases/genética , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas
4.
Kaohsiung J Med Sci ; 40(1): 23-34, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37916740

RESUMO

Docetaxel-based chemotherapy has generally been considered as one of the effective treatments for castration-resistant prostate cancer (PCa). However, clinical treatment with docetaxel often encounters a number of undesirable effects, including drug resistance. Tubulin isoforms have been previously examined for their resistance to docetaxel in many cancers, but their real mechanisms remained unclear. In this study, a series of docetaxel-resistant PC/DX cell sublines were established by chronically exposing PC3 to progressively increased concentrations of docetaxel. Western blotting results showed significantly higher expression of acetyl-tubulin, α-tubulin, ß-tubulin, γ-tubulin, and ßIII-tubulin in PC/DX25 than in parental PC3 cells. PC/DX25 with greater resistance to docetaxel had higher levels of acetyl-tubulin and mitotic centromere-associated kinesin (MCAK) than PC3 cells. This study found that docetaxel induced the expression of acetyl-tubulin and MCAK in PC3 cells at a dose- and time-dependent manner. Both mRNA and protein levels of histone deacetylase 6 (HDAC6) were significantly decreased in PC/DX25 compared with PC3 cells. PC3 increased the resistance to docetaxel by HDAC6 knockdown and Tubastatin A (HDAC6 inhibitor). Conversely, PC/DX25 reversed the sensitivity to docetaxel by MCAK knockdown. Notably, flow cytometry analysis revealed that MCAK knockdown induced significantly sub G1 fraction in PC/DX cells. Overexpression of polo-like kinase-1 increased the cell survival rate and resistance to docetaxel in PC3 cells. Moreover, epidermal growth factor receptor (EGFR) activation induced the upregulation of acetyl-tubulin in docetaxel-resistant PCa cells. These findings demonstrated that the EGFR-mediated upregulated expression of acetyl-tubulin played an important role in docetaxel-resistant PCa.


Assuntos
Neoplasias da Próstata , Tubulina (Proteína) , Masculino , Humanos , Docetaxel/farmacologia , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Regulação para Cima , Regulação para Baixo , Desacetilase 6 de Histona/genética , Desacetilase 6 de Histona/metabolismo , Desacetilase 6 de Histona/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo
5.
Foods ; 12(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37174458

RESUMO

In this study, umami-rich seasoning powder was produced from the offcuts of Taiwanese tilapia (Oreochromis mossambicus) by cooking concentration and spray drying of granules while yielding an abundance of glutamic acid (0.23 mg/100 g), glycine (0.10 mg/100 g), aspartic acid (0.11 mg/100 g), lysine (0.10 mg/100 g), and 11 other aminic acids. It exhibited water content (3.81%), water activity (0.3), powder yields (68.83%), and a good water solubility index (99.89%), while the particle microstructure was a spherical powder. Additionally, it received the highest overall preference score (7.53) in the consumer-type sensory evaluation compared to commercially available seasonings. This study proves that offcuts may be part of the human diet after proper processing and can be widely used to flavor savory food. The producers involved could increase their economic returns while meeting the environmental challenges. The practical contribution could create incremental value for products to critical stakeholders at each point in the tilapia supply chain with an operational guide for transitioning from inefficient to innovative circular practices.

6.
Int J Mol Sci ; 24(10)2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37240339

RESUMO

Seed germination is a complex process that is regulated by various exogenous and endogenous factors, in which abscisic acid (ABA) plays a crucial role. The triphosphate tunnel metalloenzyme (TTM) superfamily exists in all living organisms, but research on its biological role is limited. Here, we reveal that TTM2 functions in ABA-mediated seed germination. Our study indicates that TTM2 expression is enhanced but repressed by ABA during seed germination. Promoted TTM2 expression in 35S::TTM2-FLAG rescues ABA-mediated inhibition of seed germination and early seedling development and ttm2 mutants exhibit lower seed germination rate and reduced cotyledon greening compared with the wild type, revealing that the repression of TTM2 expression is required for ABA-mediated inhibition of seed germination and early seedling development. Further, ABA inhibits TTM2 expression by ABA insensitive 4 (ABI4) binding of TTM2 promoter and the ABA-insensitive phenotype of abi4-1 with higher TTM2 expression can be rescued by mutation of TTM2 in abi4-1 ttm2-1 mutant, indicating that TTM2 acts downstream of ABI4. In addition, TTM1, a homolog of TTM2, is not involved in ABA-mediated regulation of seed germination. In summary, our findings reveal that TTM2 acts as a downstream factor of ABI4 in ABA-mediated seed germination and early seedling growth.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Metaloproteínas , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Fatores de Transcrição/metabolismo , Germinação/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sementes/metabolismo , Plântula/metabolismo , Metaloproteínas/metabolismo , Regulação da Expressão Gênica de Plantas , Hidrolases Anidrido Ácido/genética
7.
Plant Cell ; 35(7): 2570-2591, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37040621

RESUMO

SALT OVERLY SENSITIVE1 (SOS1) is a key component of plant salt tolerance. However, how SOS1 transcription is dynamically regulated in plant response to different salinity conditions remains elusive. Here, we report that C-type Cyclin1;1 (CycC1;1) negatively regulates salt tolerance by interfering with WRKY75-mediated transcriptional activation of SOS1 in Arabidopsis (Arabidopsis thaliana). Disruption of CycC1;1 promotes SOS1 expression and salt tolerance in Arabidopsis because CycC1;1 interferes with RNA polymerase II recruitment by occupying the SOS1 promoter. Enhanced salt tolerance of the cycc1;1 mutant was completely compromised by an SOS1 mutation. Moreover, CycC1;1 physically interacts with the transcription factor WRKY75, which can bind to the SOS1 promoter and activate SOS1 expression. In contrast to the cycc1;1 mutant, the wrky75 mutant has attenuated SOS1 expression and salt tolerance, whereas overexpression of SOS1 rescues the salt sensitivity of wrky75. Intriguingly, CycC1;1 inhibits WRKY75-mediated transcriptional activation of SOS1 via their interaction. Thus, increased SOS1 expression and salt tolerance in cycc1;1 were abolished by WRKY75 mutation. Our findings demonstrate that CycC1;1 forms a complex with WRKY75 to inactivate SOS1 transcription under low salinity conditions. By contrast, under high salinity conditions, SOS1 transcription and plant salt tolerance are activated at least partially by increased WRKY75 expression but decreased CycC1;1 expression.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Tolerância ao Sal/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo
8.
Plant J ; 114(6): 1369-1384, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36948886

RESUMO

Hydrogen sulfide (H2 S) promotes plant tolerance against various environmental cues, and d-cysteine desulfhydrase (DCD) is an enzymatic source of H2 S to enhance abiotic stress resistance. However, the role of DCD-mediated H2 S production in root growth under abiotic stress remains to be further elucidated. Here, we report that DCD-mediated H2 S production alleviates osmotic stress-mediated root growth inhibition by promoting auxin homeostasis. Osmotic stress up-regulated DCD gene transcript and DCD protein levels and thus H2 S production in roots. When subjected to osmotic stress, a dcd mutant showed more severe root growth inhibition, whereas the transgenic lines DCDox overexpressing DCD exhibited less sensitivity to osmotic stress in terms of longer root compared to the wild-type. Moreover, osmotic stress inhibited root growth through repressing auxin signaling, whereas H2 S treatment significantly alleviated osmotic stress-mediated inhibition of auxin. Under osmotic stress, auxin accumulation was increased in DCDox but decreased in dcd mutant. H2 S promoted auxin biosynthesis gene expression and auxin efflux carrier PIN-FORMED 1 (PIN1) protein level under osmotic stress. Taken together, our results reveal that mannitol-induced DCD and H2 S in roots promote auxin homeostasis, contributing to alleviating the inhibition of root growth under osmotic stress.


Assuntos
Proteínas de Arabidopsis , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/metabolismo , Raízes de Plantas/metabolismo , Pressão Osmótica , Homeostase , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
9.
World J Gastrointest Oncol ; 15(1): 1-18, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36684055

RESUMO

Improvements in early screening, new diagnostic techniques, and surgical treatment have led to continuous downward trends in hepatocellular carcinoma (HCC) morbidity and mortality rates. However, high recurrence and refractory cancer after hepatectomy remain important factors affecting the long-term prognosis of HCC. The clinical characteristics and prognosis of recurrent HCC are heterogeneous, and guidelines on treatment strategies for recurrent HCC are lacking. Therapies such as surgical resection, radiofrequency ablation, and transhepatic arterial chemoembolization are effective for tumors confined to the liver, and targeted therapy is a very important treatment for unresectable recurrent HCC with systemic metastasis. With the deepening of the understanding of the immune microenvironment of HCC, blocking immune checkpoints to enhance the antitumor immune response has become a new direction for the treatment of HCC. In addition, improvements in the tumor immune microenvironment caused by local treatment may provide an opportunity to improve the therapeutic effect of HCC treatment. Ongoing and future clinical trial data of combined therapy may develop the new treatment scheme for recurrent HCC. This paper reviews the pattern of recurrent HCC and the characteristics of the immune microenvironment, demonstrates the basis for combining local treatment and systemic treatment, and reports current evidence to better understand current progress and future approaches in the treatment of recurrent HCC.

10.
Plant Cell ; 35(5): 1593-1616, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36695476

RESUMO

High salinity, an adverse environmental factor affecting about 20% of irrigated arable land worldwide, inhibits plant growth and development by causing oxidative stress, damaging cellular components, and disturbing global metabolism. However, whether and how reactive oxygen species disturb the metabolism of salt-stressed plants remain elusive. Here, we report that salt-induced hydrogen peroxide (H2O2) inhibits the activity of plastid triose phosphate isomerase (pdTPI) to promote methylglyoxal (MG) accumulation and stimulates the sulfenylation of pdTPI at cysteine 74. We also show that MG is a key factor limiting the plant growth, as a decrease in MG levels completely rescued the stunted growth and repressed salt stress tolerance of the pdtpi mutant. Furthermore, targeting CATALASE 2 into chloroplasts to prevent salt-induced overaccumulation of H2O2 conferred salt stress tolerance, revealing a role for chloroplastic H2O2 in salt-caused plant damage. In addition, we demonstrate that the H2O2-mediated accumulation of MG in turn induces H2O2 production, thus forming a regulatory loop that further inhibits the pdTPI activity in salt-stressed plants. Our findings, therefore, illustrate how salt stress induces MG production to inhibit the plant growth.


Assuntos
Peróxido de Hidrogênio , Aldeído Pirúvico , Peróxido de Hidrogênio/metabolismo , Aldeído Pirúvico/metabolismo , Estresse Salino , Estresse Oxidativo , Plantas/metabolismo , Cloroplastos/metabolismo , Estresse Fisiológico
11.
Bioinspir Biomim ; 18(2)2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36652720

RESUMO

Elephants have long been observed to grip objects with their trunk, but little is known about how they adjust their strategy for different weights. In this study, we challenge a female African elephant at Zoo Atlanta to lift 20-60 kg barbell weights with only its trunk. We measure the trunk's shape and wrinkle geometry from a frozen elephant trunk at the Smithsonian. We observe several strategies employed to accommodate heavier weights, including accelerating less, orienting the trunk vertically, and wrapping the barbell with a greater trunk length. Mathematical models show that increasing barbell weights are associated with constant trunk tensile force and an increasing barbell-wrapping surface area due to the trunk's wrinkles. Our findings may inspire the design of more adaptable soft robotic grippers that can improve grip using surface morphology such as wrinkles.


Assuntos
Estruturas Animais , Elefantes , Força Muscular , Animais , Feminino , Elefantes/fisiologia , Estruturas Animais/fisiologia
12.
Nucleic Acids Res ; 51(2): 619-630, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36546827

RESUMO

Jasmonic acid (JA) signaling plays a pivotal role in plant development and defense. MYC2 is a master transcription factor in JA signaling, and was found to be phosphorylated and negatively regulated by MAP kinase and receptor-like kinase. However, the kinases that positively regulate MYC2 through phosphorylation and promote MYC2-mediated activation of JA response have not been identified. Here, we identified CK2 as a kinase that phosphorylates MYC2 and thus regulates the JA signaling. CK2 holoenzyme can interact with MYC2 using its regulatory subunits and phosphorylate MYC2 at multiple sites with its catalytic subunits. Inhibition of CK2 activity in a dominant-negative plant line, CK2mut, repressed JA response. On the other hand, increasing CK2 activity by overexpression of CKB4, a regulatory subunit gene of CK2, enhanced JA response in a MYC2-dependent manner. Substitution of the Ser and Thr residues at phosphorylation sites of MYC2 by CK2 with Ala impaired MYC2 function in activating JA response. Further investigations evidenced that CK2 facilitated the JA-induced increase of MYC2 binding to the promoters of JA-responsive genes in vivo. Our study demonstrated that CK2 plays a positive role in JA signaling, and reveals a previously undiscovered mechanism that regulates MYC2 function.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Caseína Quinase II , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Fosfotransferases/genética , Caseína Quinase II/metabolismo
13.
Bioresour Technol ; 370: 128503, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36535615

RESUMO

This study presented a novel methodology to predict microalgae chlorophyll content from colour models using linear regression and artificial neural network. The analysis was performed using SPSS software. Type of extractant solvents and image indexes were used as the input data for the artificial neural network calculation. The findings revealed that the regression model was highly significant, with high R2 of 0.58 and RSME of 3.16, making it a useful tool for predicting the chlorophyll concentration. Simultaneously, artificial neural network model with R2 of 0.66 and low RMSE of 2.36 proved to be more accurate than regression model. The model which fitted to the experimental data indicated that acetone was a suitable extraction solvent. In comparison to the cyan-magenta-yellow-black model in image analysis, the red-greenblue model offered a better correlation. In short, the estimation of chlorophyll concentration using prediction models are rapid, more efficient, and less expensive.


Assuntos
Clorofila , Microalgas , Redes Neurais de Computação , Modelos Lineares
14.
Biomedicines ; 10(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36140385

RESUMO

Both hypernatremia and an abnormal immune response may increase hospital mortality in patients with sepsis. This study examined the association of hypernatremia with abnormal immune response and mortality in 520 adult patients with sepsis in an intensive care unit (ICU). We compared the mortality and ex vivo lipopolysaccharide (LPS)-induced inflammatory response differences among patients with hyponatremia, eunatremia, and hypernatremia, as well as between patients with acquired hypernatremia on ICU day 3 and those with sustained eunatremia over first three ICU days. Compared with eunatremia or hyponatremia, hypernatremia led to higher 7 day, 14 day, 28 day, and hospital mortality rates (p = 0.030, 0.009, 0.010, and 0.033, respectively). Compared with sustained eunatremia, acquired hypernatremia led to higher 7, 14, and 28 day mortality rates (p = 0.019, 0.042, and 0.028, respectively). The acquired hypernatremia group nonsignificantly trended toward increased hospital mortality (p = 0.056). Day 1 granulocyte colony-stimulating factor (G-CSF) and tumor necrosis factor (TNF) α levels were relatively low in patients with hypernatremia (p = 0.020 and 0.010, respectively) but relatively high in patients with acquired hypernatremia (p = 0.049 and 0.009, respectively). Thus, in ICU-admitted septic patients, hypernatremia on admission and in ICU-acquired hypernatremia were both associated with higher mortality. The higher mortality in patients with hypernatremia on admission was possibly related to the downregulation of G-CSF and TNF-α secretion after endotoxin stimulation. Compared to sustained eunatremia, acquired hypernatremia showed immunoparalysis at first and then hyperinflammation on day 3.

15.
Front Plant Sci ; 13: 924064, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909771

RESUMO

The ELO family is involved in synthesizing very-long-chain fatty acids (VLCFAs) and VLCFAs play a crucial role in plant development, protein transport, and disease resistance, but the physiological function of the plant ELO family is largely unknown. Further, while nitric oxide synthase (NOS)-like activity acts in various plant environmental responses by modulating nitric oxide (NO) accumulation, how the NOS-like activity is regulated in such different stress responses remains misty. Here, we report that the yeast mutant Δelo3 is defective in H2O2-triggered cell apoptosis with decreased NOS-like activity and NO accumulation, while its Arabidopsis homologous gene ELO2 (ELO HOMOLOG 2) could complement such defects in Δelo3. The expression of this gene is enhanced and required in plant osmotic stress response because the T-DNA insertion mutant elo2 is more sensitive to the stress than wild-type plants, and ELO2 expression could rescue the sensitivity phenotype of elo2. In addition, osmotic stress-promoted NOS-like activity and NO accumulation are significantly repressed in elo2, while exogenous application of NO donors can rescue this sensitivity of elo2 in terms of germination rate, fresh weight, chlorophyll content, and ion leakage. Furthermore, stress-responsive gene expression, proline accumulation, and catalase activity are also repressed in elo2 compared with the wild type under osmotic stress. In conclusion, our study identifies ELO2 as a pivotal factor involved in plant osmotic stress response and reveals its role in regulating NOS-like activity and NO accumulation.

16.
Dev Cell ; 57(15): 1883-1898.e5, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35809562

RESUMO

H2O2 affects the expression of genes that are involved in plant responses to diverse environmental stresses; however, the underlying mechanisms remain elusive. Here, we demonstrate that H2O2 enhances plant freezing tolerance through its effect on a protein product of low expression of osmotically responsive genes2 (LOS2). LOS2 is translated into a major product, cytosolic enolase2 (ENO2), and sometimes an alternative product, the transcription repressor c-Myc-binding protein (MBP-1). ENO2, but not MBP-1, promotes cold tolerance by binding the promoter of C-repeat/DRE binding factor1 (CBF1), a central transcription factor in plant cold signaling, thus activating its expression. Overexpression of CBF1 restores freezing sensitivity of a LOS2 loss-of-function mutant. Furthermore, cold-induced H2O2 increases nuclear import and transcriptional binding activity of ENO2 by sulfenylating cysteine 408 and thereby promotes its oligomerization. Collectively, our results illustrate how H2O2 activates plant cold responses by sulfenylating ENO2 and promoting its oligomerization, leading to enhanced nuclear translocation and transcriptional activation of CBF1.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Congelamento , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Mol Plant ; 15(6): 973-990, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35488429

RESUMO

To adapt to changing environments, plants have evolved elaborate regulatory mechanisms balancing their growth with stress responses. It is currently unclear whether and how the tryptophan (Trp), the growth-related hormone auxin, and the stress hormone abscisic acid (ABA) are coordinated in this trade-off. Here, we show that tryptophan synthase ß subunit 1 (TSB1) is involved in the coordination of Trp and ABA, thereby affecting plant growth and abiotic stress responses. Plants experiencing high salinity or drought display reduced TSB1 expression, resulting in decreased Trp and auxin accumulation and thus reduced growth. In comparison with the wild type, amiR-TSB1 lines and TSB1 mutants exhibited repressed growth under non-stress conditions but had enhanced ABA accumulation and stress tolerance when subjected to salt or drought stress. Furthermore, we found that TSB1 interacts with and inhibits ß-glucosidase 1 (BG1), which hydrolyses glucose-conjugated ABA into active ABA. Mutation of BG1 in the amiR-TSB1 lines compromised their increased ABA accumulation and enhanced stress tolerance. Moreover, stress-induced H2O2 disrupted the interaction between TSB1 and BG1 by sulfenylating cysteine-308 of TSB1, relieving the TSB1-mediated inhibition of BG1 activity. Taken together, we revealed that TSB1 serves as a key coordinator of plant growth and stress responses by balancing Trp and ABA homeostasis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Triptofano Sintase , Ácido Abscísico/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Secas , Regulação da Expressão Gênica de Plantas , Homeostase , Hormônios/metabolismo , Peróxido de Hidrogênio/metabolismo , Ácidos Indolacéticos/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico/genética , Triptofano/metabolismo , Triptofano Sintase/genética , Triptofano Sintase/metabolismo
18.
J Clin Med ; 11(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35329955

RESUMO

Background: We aimed to determine whether septic patients with liver cirrhosis (LC) had worse survival than septic patients without liver cirrhosis (WLC). We also investigated the survival of septic patients with compensated liver cirrhosis (CLC) and decompensated liver cirrhosis (DLC). Methods: This study enrolled 776 consecutive adult patients with sepsis admitted to the medical intensive care units of a tertiary referral hospital. Clinical factors and laboratory data were collected for analysis. Propensity scoring was also used for the control of selection bias. The variables included in the propensity model were age, sex, presence of diabetes mellitus, hypertension, cardiovascular accident, chronic kidney disease, malignancy, APCHE II (Acute Physiology and Chronic Health Evaluation) score, hemoglobin, and platelet data on the day when sepsis was confirmed. Seven-day, ICU, and hospital mortality were analyzed after correcting for these confounding factors. Results: Of the 776 septic patients, 64 (8.2%) septic patients presented with LC. Patients were divided into two groups­LC (n = 64) and WLC (n = 712)­which presented different rates of hospital mortality (LC: 62.5% vs. WLC: 41.0%, p = 0.001). We further separated septic patients with LC into two groups: patients with CLC (n = 24) and those with DLC (n = 40). After propensity score matching, the survival of septic patients with CLC (63.6%) was not inferior to patients WLC (54.5%) (p = 0.411). Patients with DLC had more hospital mortality, even after matching (p < 0.05). The Quick SOFA (qSOFA) score, SOFA score, and sub-SOFA score were also comparable between groups. SOFA scores were not significantly different between the CLC and WLC groups after matching. Poor SOFA scores were observed in the DLC group on days 3 and 7 after matching (p < 0.05). Conclusions: Septic patients with LC had higher mortality compared to patients WLC before matching. However, after propensity score matching, the survival of septic patients with CLC was non-inferior to patients WLC.

19.
Biomed J ; 45(4): 665-674, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34482015

RESUMO

BACKGROUND: Sepsis-associated acute kidney injury (AKI) often worsens with the deterioration of a patient's condition. Therefore, we hypothesized that monitoring AKI dynamically from day 1 to day 3 was potential to predict hospital mortality. Specifically, we explored whether monitoring AKI dynamically in the intensive care unit (ICU) could be a sepsis phenotype predictive of mortality. A new classification was established based on the change in the AKI stage from admission day 1 and day 3. We compared the hospital mortality, cytokines, and immune response pattern between each group. METHODS: We retrospectively enrolled 523 patients with sepsis, and we calculated the AKI stages on day 1 and day 3 admission to ICUs. Among these 523 people, 388 of them were assigned to normal, improved, and deteriorated groups according to the changes in the AKI stages. 263 of which did not develop AKI on day 1 and day 3 (normal group). The AKI stage improved in 68 patients (improved group) and worsened in 57 (deteriorated group). We compared the mortality rates between the groups, and identified the relationship between the dynamic AKI status, immune response patterns, and cytokine levels. RESULTS: The hospital mortality rate in the deteriorated group was higher than that in the non-deteriorated group (combination of normal and improved group) (p = 0.004). Additionally, according to the Kaplan-Meier analysis, the non-deteriorated group had a distinct hospital survival curve (p = 0.004). Furthermore, both the overexpression of tumor necrosis factor-α and decreased monocyte expression of human leukocyte antigen-DR were present in the deteriorated group. CONCLUSIONS: The deteriorated group was associated with a higher hospital mortality rate, potentially resulting from an abnormal inflammatory response. Worsening AKI in the first 3 days of ICU admission may be a sepsis phenotype predictive of hospital mortality.


Assuntos
Injúria Renal Aguda , Sepse , Injúria Renal Aguda/complicações , Injúria Renal Aguda/diagnóstico , Antígenos HLA , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Rim , Fenótipo , Estudos Retrospectivos , Sepse/complicações , Sepse/diagnóstico , Fator de Necrose Tumoral alfa
20.
Health Promot Perspect ; 11(3): 288-298, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660223

RESUMO

Background: To adapt the scientific evaluation tool for the confusion evaluation of health rumors and to test this tool to the confusion evaluation of coronavirus disease 2019 (COVID-19)-related health rumors on Chinese online platforms during the outbreak period of COVID-19in China. Methods: The design of our study was systematic evaluation of COVID-19-related health rumors. Retrieved from 7 rumor-repellent platforms, rumors about COVID-19 were collected during the publication from December 1, 2019, to February 6, 2020, and their origins were traced. Researchers evaluated rumors using the confusion evaluation tool in 6 dimensions(creators, evidence selection, evidence evaluation, evidence application, backing and publication platform, conflict of interest). Items were scored using a seven-point Likert scale. The scores were converted into percentages, and the median of rumors from different sources was compared with rank-sum test. Results: Our research included 127 rumors. Scores were converted to percentages, median and interquartile range are used to describe the data. The median score: creators 25.00%(interquartile range, IQR, 16.67-37.50%), evidence selection 27.78% (IQR, 13.89-44.44%),evidence evaluation 33.33% (IQR, 25.00-45.83%), evidence application 36.11% (IQR, 22.22-47.22%), backing and publication platform 8.33% (IQR, 4.17-20.83%), conflict of interest75.00% (IQR, 50.00-83.33%). Almost 40% rumors came from WeChat and the rumors with the lowest scores were concentrated on the WeChat platform. The rumors about prevention methods have relatively lower scores. Conclusion: Most rumors included were not highly confusing for evaluators of this project.WeChat is the "worst-hit area" of COVID-19 related health rumors. More than half rumors focus on the description of prevention methods, which reflects the panic, anxiety and blind conformity of the public under public health emergencies.

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