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1.
FASEB J ; 38(2): e23406, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38193601

RESUMO

Cancer-associated fibroblast (CAF) has emerged as a key contributor to the remodeling of tumor microenvironment through the expression and secretion of extracellular matrix (ECM) proteins, thereby promoting carcinogenesis. However, the precise contribution of ECM proteins from CAFs to gastric carcinogenesis remains poorly understood. In this study, we find that matrilin-3 (MATN3), an upregulated ECM protein associated with poorer prognosis in gastric cancer patients, originates from CAFs in gastric cancer tissues. Ectopic expression of MATN3 in CAFs significantly promotes the invasion of gastric cancer cells, which can be attenuated by neutralizing MATN3 with its antibody. Notably, a portion of MATN3 protein is found to form puncta in gastric cancer tissues ECM. MATN3 undergoes phase separation, which is mediated by its low complexity (LC) and coiled-coil (CC) domains. Moreover, overexpression of MATN3 deleted with either LC or CC in CAFs is unable to promote the invasion of gastric cancer cells, suggesting that LC or CC domain is required for the effect of CAF-secreted MATN3 in gastric cancer cell invasion. Additionally, orthotopic co-injection of gastric cancer cells and CAFs expressing MATN3, but not its ΔLC and ΔCC mutants, leads to enhanced gastric cancer cell invasion in mouse models. Collectively, our works suggest that MATN3 is secreted by CAFs and undergoes phase separation, which promotes gastric cancer invasion.


Assuntos
Fibroblastos Associados a Câncer , Proteínas Matrilinas , Neoplasias Gástricas , Animais , Humanos , Camundongos , Carcinogênese , Proteínas Matrilinas/genética , Invasividade Neoplásica , Separação de Fases , Neoplasias Gástricas/genética , Microambiente Tumoral
2.
J Magn Reson Imaging ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38390981

RESUMO

BACKGROUND: Different placenta accreta spectrum (PAS) subtypes pose varying surgical risks to the parturient. Machine learning model has the potential to diagnose PAS disorder. PURPOSE: To develop a cascaded deep semantic-radiomic-clinical (DRC) model for diagnosing PAS and its subtypes based on T2-weighted MRI. STUDY TYPE: Retrospective. POPULATION: 361 pregnant women (mean age: 33.10 ± 4.37 years), suspected of PAS, divided into segment training cohort (N = 40), internal training cohort (N = 139), internal testing cohort (N = 60), and external testing cohort (N = 122). FIELD STRENGTH/SEQUENCE: Coronal T2-weighted sequence at 1.5 T and 3.0 T. ASSESSMENT: Clinical characteristics such as history of uterine surgery and the presence of placenta previa, complete placenta previa and dangerous placenta previa were extracted from clinical records. The DRC model (incorporating radiomics, deep semantic features, and clinical characteristics), a cumulative radiological score method performed by radiologists, and other models (including a radiomics and clinical, the clinical, radiomics and deep learning models) were developed for PAS disorder diagnosing (existence of PAS and its subtypes). STATISTICAL TESTS: AUC, ACC, Student's t-test, the Mann-Whitney U test, chi-squared test, dice coefficient, intraclass correlation coefficients, least absolute shrinkage and selection operator regression, receiver operating characteristic curve, calibration curve with the Hosmer-Lemeshow test, decision curve analysis, DeLong test, and McNemar test. P < 0.05 indicated a significant difference. RESULTS: In PAS diagnosis, the DRC-1 outperformed than other models (AUC = 0.850 and 0.841 in internal and external testing cohorts, respectively). In PAS subtype classification (abnormal adherent placenta and abnormal invasive placenta), DRC-2 model performed similarly with radiologists (P = 0.773 and 0.579 in the internal testing cohort and P = 0.429 and 0.874 in the external testing cohort, respectively). DATA CONCLUSION: The DRC model offers efficiency and high diagnostic sensitivity in diagnosis, aiding in surgical planning. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

3.
Ecotoxicol Environ Saf ; 271: 115957, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219617

RESUMO

The perennial ryegrass Lolium perenne can be used in conjunction with cadmium (Cd)-tolerant bacteria such as Cdq4-2 (Enterococcus spp.) for bioremediation of Cd-contaminated soil. In this study, a theoretical basis was provided to increase the efficiency of L. perenne remediation of Cd-contaminated soil using microorganisms to maintain the stability of the soil microbiome. The experimental design involved three treatment groups: CK (soil without Cd addition) as the control, 20 mg·kg-1 Cd-contaminated soil, and 20 mg·kg-1 Cd-contaminated soil + Cdq4-2, all planted with L. perenne. The soil was collected on day 60 to determine the soil microbial activity and bacterial community structure and to analyze the correlation between soil variables, the bacterial community, available Cd content in the soil, Cd accumulation, and L. perenne growth. The soil microbial activity and bacterial community diversity decreased under Cd stress, and the soil microbial community composition was changed; while inoculation with Cdq4-2 significantly increased soil basal respiration and the activities of urease, invertase, and fluorescein diacetate (FDA) hydrolase by 83.65%, 79.72%, 19.88%, and 96.15% respectively; and the stability of the community structure was also enhanced. The Actinobacteriota biomass, the amount of available Cd, and the above- and belowground Cd content of L. perenne were significantly negatively correlated with the total phosphorus, total potassium, and pH. The activity of urease, invertase, and FDA hydrolase were significantly positively correlated with the biomasses of Acidobacteriota and L. perenne and significantly negatively correlated with the Chloroflexi biomass. Further, the available soil Cd content and the above- and belowground Cd levels of L. perenne were significantly positively correlated with the Actinobacteriota biomass and significantly negatively correlated with the Gemmatimonadetes biomass. Overall, inoculating Cd-tolerant bacteria improved the microbial activity, diversity, and abundance, and changed the microbial community composition, facilitating the remediation of Cd-contaminated soil by L. perenne.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/toxicidade , Cádmio/análise , Biodegradação Ambiental , Urease , beta-Frutofuranosidase , Bactérias , Solo/química , Poluentes do Solo/toxicidade , Poluentes do Solo/análise
4.
J Environ Manage ; 354: 120486, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417363

RESUMO

Alterations in water regimes or nitrogen (N) availability lead to shifts in the assemblage of rhizosphere microbial community; however, how the rhizosphere microbiome response to concurrent changes in water and N availability remains largely unclear. Herein, we investigated the taxonomic and functional characteristics of rhizobacteria associated with stevia (Stevia rebaudiana Bertoni) under varying combinations of water and N levels. Community diversity and predicted functions of rhizobacteria were predominantly altered by drought stress, with N-starvation modulating these effects. Moreover, N fertilization simplified the ecological interactions within rhizobacterial communities and heightened the relative role of stochastic processes on community assembly. In terms of rhizobacterial composition, we observed both common and distinctive changes in drought-responsive bacterial taxa under different N conditions. Generally, the relative abundance of Proteobacteria and Bacteroidetes phyla were depleted by drought stress but the Actinobacteria phylum showed increases. The rhizobacterial responses to drought stress were influenced by N availability, where the positive response of δ-proteobacteria and the negative response of α- and γ-proteobacteria, along with Bacteroidetes, were further heightened under N starvation. By contrast, under N fertilization conditions, an amplified negative or positive response to drought were demonstrated in Firmicutes and Actinobacteria phyla, respectively. Further, the drought-responsive rhizobacteria were mostly phylogenetically similar, but this pattern was modulated under N-rich conditions. Overall, our findings indicate an N-dependent specific restructuring of rhizosphere bacteria under drought stress. These changes in the rhizosphere microbiome could contribute to enhancing plant stress tolerance.


Assuntos
Actinobacteria , Stevia , Secas , Bactérias , Proteobactérias , Rizosfera , Água , Microbiologia do Solo
5.
Altern Ther Health Med ; 29(3): 134-139, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36735710

RESUMO

Objective: This study was designed to survey the effect and the mechanism of action of calorie restriction combined with high-intensity interval training (HIIT) on the browning of white adipose tissue. Methods: For the human study population, obese adult males were randomly assigned to one of three major groups: the control group (CN group), the calorie restriction combined with HIIT group (CR+HIIT group) and the HIIT group. After 3 months of training, body composition was measured. For the rodent study population, Sprague Dawley rats were randomly split into a normal diet control group (CON group) and an obesity model group. After successful obesity modeling, the latter was divided into the obesity control group (HON group), the calorie restriction plus HIIT group (ONE group) and the HIIT group (OHE group), with 8 animals in each group. A treadmill was used for training 5 days a week for 10 weeks. The messenger RNA (mRNA) expression of uncoupling protein 1 (UCP1), Prdm16 gene, and Cidea gene in visceral adipose tissue were detected with real-time polymer chain reaction (RT-qPCR), while the protein levels of UCP1, PPARγ and PGC-1α in visceral adipose tissue (VAT) were detected by western blot analysis. Results: Body weight and body fat rate in the human experiments demonstrated that fat mass, body weight and body fat rate in the CR+HIIT group were clearly lower than in the CN group. In the rat model, the body fat rate and body weight in the HON group were significantly higher than in the CON group, which indicated that the obesity model was successfully generated. As expected, the body fat rate and body weight in the ONE and OHE groups were considerably lower than in the HON group. Moreover, the body fat rate in the ONE group was considerably lower than in the OHE group. Further investigation indicated that the area under this curve (AUC) of oral glucose tolerance test (AUCOGTT), insulin (INS) levels and fasting blood glucose (FBG) levels in the HON group were more significantly increased than in the CON group, while AUCOGTT and INS levels in the ONE and OHE groups were considerably lower than in the HON group. Hematoxylin and eosin (H&E) staining showed that, compared with the CON group, the adipocyte area in the HON group was expanded, but narrowed in the ONE and OHE groups. In addition, the adipocyte area in the ONE group was apparently smaller than in the OHE group. We also compared molecular markers among the groups. RT-qPCR analysis showed that the expression of UCP1, Prdm16 and Cidea had been downregulated in the HON group compared with CON group but upregulated in the HON group compared with the ONE and OHE groups. Western blot analysis indicated that UCP1 in the HON group was lower than in the CON group but higher than in the ONE and OHE groups. In addition, the protein level of UCP1 was upregulated in the ONE group compared with the OHE group. Furthermore, expression levels of PPARγ coactivator-1α (PGC-1α) and peroxisome proliferator-activated receptor gamma (PPARγ) were downregulated in the HON group compared with the CON group, then further downregulated in the ONE and OHE groups compared with the HON group. In addition, the PGC-1α level in the ONE group was greatly improved compared with the OHE group. Conclusion: Calorie restriction integrated with HIIT and HIIT alone upregulates PPARγ, PGC- 1α, as well as UCP1 in VAT of obese rats, promoting the browning of visceral fat and ultimately achieving fat loss. Calorie restriction integrated with HIIT is more effective than HIIT alone for fat loss.


Assuntos
Treinamento Intervalado de Alta Intensidade , PPAR gama , Humanos , Masculino , Adulto , Ratos , Animais , PPAR gama/genética , PPAR gama/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Restrição Calórica , Ratos Sprague-Dawley , Tecido Adiposo Branco/metabolismo , Obesidade/terapia , Peso Corporal
6.
Sensors (Basel) ; 23(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37571514

RESUMO

The diagnosis of bearing faults is an important guarantee for the healthy operation of mechanical equipment. Due to the time-varying working conditions of mechanical equipment, it is necessary to achieve bearing fault diagnosis under time-varying working conditions. However, the superposition of the two-dimensional working conditions of speed and acceleration brings great difficulties to diagnosis via data-driven models. The long short-term memory (LSTM) model based on the infinitesimal method is an effective method to solve this problem, but its performance still has certain limitations. On this basis, this article proposes a model for fault diagnosis under time-varying operating conditions that combines a residual network model (ResNet) and a gate recurrent unit (model) (GRU). Firstly, the samples were segmented, and feature extraction was performed using ResNet. We then used GRU to process the information. Finally, the classification results were output through the output network. This model could ignore the influence of acceleration and achieve high fault diagnosis accuracy under time-varying working conditions. In addition, we used t-SNE to reduce the dimensionality of the features and analyzed the role of each layer in the model. Experiments showed that this method had a better performance compared with existing bearing fault diagnosis methods.

7.
Entropy (Basel) ; 25(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37510011

RESUMO

In machine learning and data analysis, dimensionality reduction and high-dimensional data visualization can be accomplished by manifold learning using a t-Distributed Stochastic Neighbor Embedding (t-SNE) algorithm. We significantly improve this manifold learning scheme by introducing a preprocessing strategy for the t-SNE algorithm. In our preprocessing, we exploit Laplacian eigenmaps to reduce the high-dimensional data first, which can aggregate each data cluster and reduce the Kullback-Leibler divergence (KLD) remarkably. Moreover, the k-nearest-neighbor (KNN) algorithm is also involved in our preprocessing to enhance the visualization performance and reduce the computation and space complexity. We compare the performance of our strategy with that of the standard t-SNE on the MNIST dataset. The experiment results show that our strategy exhibits a stronger ability to separate different clusters as well as keep data of the same kind much closer to each other. Moreover, the KLD can be reduced by about 30% at the cost of increasing the complexity in terms of runtime by only 1-2%.

8.
Adv Funct Mater ; 32(40): 2204462, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35942271

RESUMO

SARS-CoV-2 has led to a worldwide pandemic, catastrophically impacting public health and the global economy. Herein, a new class of lipid-modified polymer poly (ß-amino esters) (L-PBAEs) is developed via enzyme-catalyzed esterification and further formulation of the L-PBAEs with poly(d,l-lactide-coglycolide)-b-poly(ethylene glycol) (PLGA-PEG) leads to self-assembly into a "particle-in-particle" (PNP) nanostructure for gene delivery. Out of 24 PNP candidates, the top-performing PNP/C12-PBAE nanoparticles efficiently deliver both DNA and mRNA in vitro and in vivo, presenting enhanced transfection efficacy, sustained gene release behavior, and excellent stability for at least 12 months of storage at -20 °C after lyophilization without loss of transfection efficacy. Encapsulated with spike encoded plasmid DNA and mRNA, the lipid-modified polymeric PNP COVID-19 vaccines successfully elicit spike-specific antibodies and Th1-biased T cell immune responses in immunized mice even after 12 months of lyophilized storage at -20 °C. This newly developed lipid-polymer hybrid PNP nanoparticle system demonstrates a new strategy for both plasmid DNA and mRNA delivery with the capability of long-term lyophilized storage.

9.
Small ; 18(10): e2106649, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34921591

RESUMO

Nature creates fascinating self-organized spatiotemporal patterns through the delicate control of reaction-diffusion dynamics. As the primary unit of cortical bone, osteon has concentric lamellar architecture, which plays a crucial role in the mechanical and physiological functions of bone. However, it remains a great challenge to fabricate the osteon-like structure in a natural self-organization way. Taking advantage of the nonequilibrium reaction in hydrogels, a simple mineralization strategy to closely mimic the formation of osteon in a mild physiological condition is developed. By constructing two reverse concentration gradients of ions from periphery to interior of cylindrical hydrogel, spatiotemporal self-organization of calcium phosphate in concentric rings is generated. It is noteworthy that minerals in different layers possess diverse contents and crystalline phases, which further guide the adhesion and spread of osteoblasts on these patterns, resembling the architecture and cytological behavior of osteon. Besides, theoretical data indicates the predominate role of ion concentrations and pH values of solution, in good accordance with experimental results. Independent of precise instruments, this lifelike method is easily obtained, cost-efficient, and effectively imitates the mineral deposition in osteon from a physiochemical view. The strategy may be expanded to develop other functional material patterns via spatiotemporal self-organization.


Assuntos
Ósteon , Hidrogéis , Osso e Ossos , Ósteon/fisiologia , Hidrogéis/química , Minerais , Osteoblastos
10.
J Org Chem ; 87(10): 6630-6637, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35481748

RESUMO

Two types of "parental" BN-dibenzo[f,k]tetraphenes (BNDBT-1 and BNDBT-2) have been synthesized via a transition-metal-catalyzed tandem cross-coupling reaction as key steps. Both BNDBT-1 and BNDBT-2 are fully characterized; one of them is unambiguously confirmed by a single X-ray crystal structure. Compared to its all-carbon analogue DBT, BNDBT-1 and BNDBT-2 exhibit a higher highest occupied molecular orbital (HOMO) and lower lowest unoccupied molecular orbital (LUMO) energy, while the BN doping position slightly influences the HOMO and LUMO energies of BNDBT-1 and BNDBT-2. Both BNDBT-1 and BNDBT-2 exhibit red-shifted absorption and emission spectra and higher emission efficiencies, as compared to their carbonaceous analogue DBT. Moreover, organic light emitting diodes were fabricated using BNDBT-1 and BNDBT-2 as emitters, demonstrating their potential applications.

11.
J Org Chem ; 87(19): 12986-12996, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36149831

RESUMO

Boron/nitrogen-doped acenaphthylenes, a new class of BN-doped cyclopenta-fused polycyclic aromatic hydrocarbons, were synthesized via indole-directed C-H borylation. The reference molecule BN-acenaphthene was also synthesized in a similar manner. Both BN-acenaphthylene and BN-acenaphthene were unequivocally characterized by single-crystal X-ray analysis. The aromaticities of each ring in BN-acenaphthylenes were quantified by experimental and theoretical methods. Moreover, doping the BN unit into acenaphthylene can increase the LUMO level and decrease the HOMO level, resulting in wider HOMO-LUMO energy gaps. Furthermore, regioselective bromination of BN-acenaphthylene (B-Mes) afforded monobrominated BN-acenaphthylene in good yield. Subsequently, cross-coupling of brominated BN-acenaphthylene gave a series of BN-acenaphthylene derivatives. In addition, the photophysical properties of these BN-acenaphthylene derivatives can be fine-tuned by the substituents on the BN-acenaphthylene scaffold.

12.
BMC Urol ; 22(1): 9, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093045

RESUMO

BACKGROUND: Leiomyoma of the seminal vesicle is a rare leiomyoma characterized by the formation of benign leiomyomatous tissue within the seminal vesicle. Although histologically benign, excessive size can lead to urinary system disease if left untreated. Herein, we report a case of a seminal vesicle epithelioid leiomyoma. CASE PRESENTATION: A 36-year-old Chinese man sought medical attention at our hospital for urination pain and hemospermia. CT showed a 5.3 cm × 5.0 cm seminal vesicle mass with a mixed density in the right seminal vesicle. The gross specimen showed light yellow, gray, and white tissues, with softness and hemorrhage in some places. Histologically, it showed classic spindle cell proliferation, with spindle cells arranged in fascicles, and mitosis was rare. Immunohistochemistry showed frequent expression of smooth muscle markers, such as calponin, SMA, and desmin. A diagnosis of epithelioid leiomyoma was proposed according to the immunohistochemical findings and morphology. The patient did not receive adjuvant therapy. There was no evidence of tumor recurrence in the 10 months after surgery. CONCLUSIONS: We report the first case of epithelioid leiomyoma in the seminal vesicle. This disease should be included in the differential diagnostic list of seminal vesicle tumors with epithelioid morphology.


Assuntos
Neoplasias dos Genitais Masculinos/patologia , Leiomioma Epitelioide/patologia , Glândulas Seminais , Adulto , Humanos , Masculino
13.
Ecotoxicol Environ Saf ; 229: 113079, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915222

RESUMO

Oil pollution poses a great threat to environments and makes the remediation of oil-contaminated soils an urgent task. Microorganisms are the main biological factor for oil removal in the environment but microbial remediation is greatly affected by environmental factors. For our research, we inoculated three species of bacterivorous nematodes into oil-contaminated soil to explore how bacterivorous nematodes affect soil microbial activities and community structure in contaminated soil, as well as how efficiently different nematodes remove oil pollution from the soil. Six treatments were set in this experiment: sterilized oil-contaminated soil (SOC); nematode-free soil (S); oil-contaminated soil (OC); oil-contaminated soil + Caenorhabditis elegans (OCN1); oil-contaminated soil + Cephalobus persegnis (OCN2); oil-contaminated soil + Rhabditis marina (OCN3) for a 168-day incubation experiment. After the experiment was done, the oil contents in SOC, OC, OCN1, OCN2, and OCN3 were reduced by 6.5%, 32.3%, 38.2%, 42.8%, and 40.2%, respectively, compared with the beginning of the experiment. The amount of phospholipid fatty acids (PLFAs) of Gram-negative bacteria in OC, OCN1, OCN2, and OCN3 was increased by 50.9%, 43.4%, 37.7%, and 47.9%, respectively, compared with that of S. During the 168-day incubation period, the maximum growth of the number of nematodes in OCN1, OCN2, and OCN3 compared with the initial number of the nematodes were 2.25-, 1.52-, and 1.65-fold, respectively. The amount of oil residue in the contaminated soil negatively correlated with the populations of nematodes, total microorganisms, Gram-negative bacteria, actinomycetes, and eukaryotes. Thus, oil pollution increased the number of Gram-negative bacteria, decreased the ratio of Gram-positive bacteria/Gram-negative bacteria and Fungi/Bacteria significantly, and altered the community structure of soil microorganisms. Each species of bacterivorous nematodes has got its unique effect on the microbial activity and community structure in oil contaminated soils, but those tested can promote oil degradation and thus improve the environment of oil contaminated soils.


Assuntos
Microbiota , Nematoides , Poluentes do Solo , Animais , Biodegradação Ambiental , Solo , Microbiologia do Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
14.
Plant Cell Rep ; 40(9): 1709-1722, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34129077

RESUMO

KEY MESSAGE: Transcriptome analysis revealed the potential mechanism of nitrogen regulating steviol glycosides synthesis via shifting of leaf carbon metabolic flux or inducing certain transcription factors. Nitrogen (N) plays key regulatory roles in both stevia (Stevia rebaudiana) growth and the synthesis of its functional metabolite steviol glycosides (SGs), but the mechanism by which this nutrient regulates SGs synthesis remains to be elucidated. To address this question, a pot experiment was performed in a greenhouse where stevia plants fertilized with N (the control as CK plants) and compared with plants without the supply of N. Physiological and biochemical analyses were conducted to test the growth and metabolic responses of plants to N regimes. Our results showed that N deficiency significantly inhibited plant growth and leaf photosynthesis, while increased leaf SGs contents in stevia (49.97, 46.64 and 84.80% respectively for rebaudioside A, stevioside, and rebaudioside C), which may be partly due to "concentration effect". Then, transcriptome analysis was conducted to understand the underlying mechanisms. A total of 535 differentially expressed genes were identified, and carbon metabolism-related events were highlighted by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Many of these genes were significantly upregulated by N-deficiency, including those involved in "phenylpropanoid biosynthesis", "flavonoid biosynthesis" and "starch and sucrose metabolism". Our study also analyzed the expression patterns of SGs synthesis-related genes under two N regimes and the potential transcription factors linking N nutrition and SG metabolism. N-deficiency may promote SGs synthesis by changing the carbon metabolism flux or inducing certain transcription factors. Our results provide deeper insight into the relationship between N nutrition and SGs synthesis in stevia plants.


Assuntos
Diterpenos do Tipo Caurano/metabolismo , Folhas de Planta/metabolismo , Stevia/genética , Stevia/metabolismo , Carbono/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glucosídeos/metabolismo , Glicosídeos/metabolismo , Nitrogênio/metabolismo , Oligossacarídeos/metabolismo , Folhas de Planta/genética , Proteínas de Plantas/genética , Reprodutibilidade dos Testes , Stevia/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445254

RESUMO

Nitrogen forms (nitrate (NO3-) or ammonium (NH4+)) are vital to plant growth and metabolism. In stevia (Stevia rebaudiana), it is important to assess whether nitrogen forms can influence the synthesis of the high-value terpene metabolites-steviol glycosides (SGs), together with the underlying mechanisms. Field and pot experiments were performed where stevia plants were fertilized with either NO3- or NH4+ nutrition to the same level of nitrogen. Physiological measurements suggested that nitrogen forms had no significant impact on biomass and the total nitrogen content of stevia leaves, but NO3--enhanced leaf SGs contents. Transcriptomic analysis identified 397 genes that were differentially expressed (DEGs) between NO3- and NH4+ treatments. Assessment of the DEGs highlighted the responses in secondary metabolism, particularly in terpenoid metabolism, to nitrogen forms. Further examinations of the expression patterns of SGs synthesis-related genes and potential transcription factors suggested that GGPPS and CPS genes, as well as the WRKY and MYB transcription factors, could be driving N form-regulated SG synthesis. We concluded that NO3-, rather than NH4+, can promote leaf SG synthesis via the NO3--MYB/WRKY-GGPPS/CPS module. Our study suggests that insights into the molecular mechanism of how SG synthesis can be affected by nitrogen forms.


Assuntos
Amônia/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glucosídeos/biossíntese , Nitratos/metabolismo , Stevia/metabolismo , Transcrição Gênica/efeitos dos fármacos , Diterpenos do Tipo Caurano , Perfilação da Expressão Gênica , Glucosídeos/genética , Nitratos/farmacologia , Stevia/genética
16.
Sheng Li Xue Bao ; 73(2): 263-274, 2021 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-33903888

RESUMO

The present study aims to investigate the effects of aerobic exercise and resistance exercise on lipid metabolism of skeletal muscle in high-fat diet (HFD)-induced insulin-resistant (IR) rats and the underlying mechanisms. Male Sprague-Dawley (SD) rats at age of 10 weeks were fed with HFD for 10 weeks to establish IR model. The IR rats were then randomly assigned into 3 groups, including IR control (IR) group, aerobic exercise (AE) group and resistance exercise (RE) group. An additional chow diet sedentary control (CON) group was used as well. Fasting blood glucose (FBG), insulin (FIN), glucagon and lipids, as well as triacylglycerol (TG), free fatty acids (FFA), and the protein expression of fatty acid translocase/cluster of differentiation 36 (FAT/CD36), carnitine palmitoyltransferase-1 (CPT-1), stearoyl-CoA desaturase-1 (SCD-1) and peroxisome proliferators-activated receptors γ (PPARγ) in skeletal muscles were measured after 8-week exercise interventions. The results showed that the contents of FBG, FIN, and LDL-C were increased by IR compared with CON group, and significantly decreased by aerobic exercise and resistance exercise; while aerobic exercise induced an increase in HDL-C as well. Furthermore, IR exhibited no significant effects on TG content of skeletal muscles, but significantly increased FFA level. Both aerobic and resistance exercise led to a decrease in TG content, and FFA level was increased by aerobic exercise but deceased by resistance exercise. In addition, the protein expression of FAT/CD36, SCD-1 and PPARγ was increased and that of CPT-1 was decreased by IR, while both types of exercise resulted in a decrease in the protein expression of FAT/CD36, SCD-1 and PPARγ, and an increase in CPT-1. In conclusion, aerobic and resistance exercise may attenuate IR through decreasing HFD-induced ectopic fat deposition and increasing ß-oxidation of fatty acids in skeletal muscle cells, and resistance exercise shows a greater improvement in lipid metabolism of skeletal muscles than aerobic exercise.


Assuntos
Resistência à Insulina , Insulina , Animais , Dieta Hiperlipídica , Insulina/metabolismo , Metabolismo dos Lipídeos , Lipídeos , Masculino , Músculo Esquelético/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Sheng Li Xue Bao ; 73(1): 42-50, 2021 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-33665659

RESUMO

This study was designed to evaluate the role of short-chain fatty acid butyrate acid on intestinal morphology and function, and atherosclerotic plaque formation in apolipoprotein E-knockout (ApoE-/-) mice. ApoE-/- mice on high-fat, high-cholesterol diet were treated with butyrate acid (200 mmol/L) or NaCl (control) in the drinking water for 12 weeks, followed by histological evaluations of atherosclerotic lesion in aorta. Real-time PCR analysis and ELISA were used to measure the expression levels of proinflammatory cytokines. Butyrate acid significantly attenuated high-fat, high-cholesterol diet-induced atherosclerotic plaque formation in ApoE-/- mice. Butyrate acid prevented high-fat, high-cholesterol diet-induced inflammation in both the aorta and the circulation, as evidenced by reduced expression of proinflammatory cytokines. These changes were accompanied by a marked attenuation in metabolic endotoxemia lipopolysaccharide (LPS). Butyrate acid induced intestinal expression of the tight junction proteins (Occludin and zona occuldens protein-1), thereby preventing the gut permeability. Butyrate acid dose-dependently upregulated the expression of the tight junction proteins in Caco-2 cells in GPR41-dependent manner. In conclusion, butyrate acid attenuates atherosclerotic lesions by ameliorating metabolic endotoxemia-induced inflammation through restoration of the gut barrier.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Apolipoproteínas E/genética , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Butiratos/farmacologia , Células CACO-2 , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos Voláteis , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
18.
Mol Biol Rep ; 47(5): 3577-3584, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32314186

RESUMO

We herein report the preparation of a full-length raucaffricine-O-beta-D-glucosidase gene of stevia rebaudiana Bertoni (named SrRG1, GenBank accession number MK920450). Sequence analysis indicated SrRG1 consists of a 1650 bp open reading frame encoding a protein of 549 amino acids. Its deduced amino acid sequence showed a high identity of 82% with a raucaffricine-O-beta-D-glucosidase from H. annuus of glycoside hydrolase family 1. The expression pattern analyzed by real-time quantitative PCR showed no significant difference among different tissues, developmental stages, and cultivars under normal growth conditions. Furthermore, the gene function of SrRG1 was preliminarily studied by agrobacterium-mediated transformation on instantaneous expression. In the test of agrobacterium-mediated transformation on instantaneous expression, it was observed that overexpression of SrRG1 increased the accumulation of steviol content and decreased the major components and total SGs contents. Such results demonstrated that SrRG1 may participate in the steviol glycosides catabolic pathway. However, the effect of silencing construct infiltration on steviol and SGs content was not significant and its expression pattern was constitutive, which most probably, attributed the hydrolysis of SGs to the secondary activity of SrRG1. This study firstly identified the bate-glucosidase in stevia and advances our understanding of steviol glycosides hydrolyzation.


Assuntos
Diterpenos do Tipo Caurano/metabolismo , Glucosídeos/metabolismo , Stevia/genética , beta-Glucosidase/metabolismo , Diterpenos do Tipo Caurano/análise , Regulação da Expressão Gênica de Plantas/genética , Glicosídeos/análise , Folhas de Planta/genética , Stevia/metabolismo , beta-Glucosidase/genética
19.
Mol Biol Rep ; 47(11): 8739-8746, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33099759

RESUMO

Stevia rebaudiana Bertoni is an important economic crop that is well known for its secondary metabolites, steviol glycosides (SGs), found in leaves. Because the enzymes of deglycosylation (glycoside hydrolases) play important roles in SGs biosynthetic processes, our study is focused on the functions of ß-glucosidases in SGs catabolism in stevia. We cloned and characterized 19 stevia GH1 genes based on transcriptomic sequences. The 19 genes were divided into five putative subfamilies in Arabidopsis. Conserved motifs in the SrGH1 proteins were analysed using the online motif-based sequence analysis tool, MEME. Most of the identified proteins contain the conserved 'TFNEP' motif (contains the catalytic acid/base) and 'ITENG' motif (contains the catalytic nucleophile). Furthermore, the steviol glycoside content and expression of these 19 genes were characterized under constant darkness. The dark treatment lowered the steviol glycoside content significantly, while SrBGLU16 responded to darkness and was markedly upregulated. This study is the first transcriptome-wide analysis of the GH1 family in Stevia rebaudiana. The sequences of 19 SrGH1 members and their expression when grown in darkness were characterized. Among the 19 genes, SrBGLU16 was markedly upregulated by darkness. Thus, we identified SrBGLU16 for further investigation as a possible steviol glycoside beta-glucosidase.


Assuntos
Celulases , Escuridão , Genes de Plantas , Stevia , Celulases/genética , Celulases/metabolismo , Diterpenos do Tipo Caurano/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosídeos/metabolismo , Stevia/enzimologia , Stevia/genética , Transcriptoma
20.
Int J Clin Oncol ; 25(6): 1105-1114, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32206938

RESUMO

BACKGROUND: Gastric cancer (GC) is the fifth most common malignancy worldwide and the third leading cause of cancer-related mortality. In recent years, SAMD14 has been studied in various malignant cancers; however, little is known about the exact mechanisms of SAMD14 involvement in carcinogenesis and malignant progression. METHODS: 60 paired GC-normal gastric tissues were evaluated for their SAMD14 mRNA expression in relation to SAMD14 gene promoter methylation. GC patient survival was assessed by Kaplan-Meier analyses and a Cox's proportional hazard model was employed for multivariate analyses. RESULTS: SAMD14 expression was significantly inversely correlated with the Borrmann type (P = 0.017), lymph node metastasis (P = 0.006) and tumor-node-metastasis (TNM) stage (P = 0.033). Methylation-specific PCR (MSP) revealed hyper-methylation of the SAMD14 promoter in 56.7% (34/60) of the primary GC tissues tested and in 10% (6/60) of matched non-malignant tissues. The SAMD14 promoter methylation status was also related to pathological differentiation, Borrmann type, TNM stage and lymph node metastasis. The results showed SAMD14 expression was significantly downregulated in Borrmann type, lymph node metastasis and TNM stage, which showed significantly higher methylation. SAMD14 promoter hyper-methylation was significantly associated with a poor prognosis and could serve as an independent marker for survival using multivariate Cox regression analysis. CONCLUSIONS: Our results indicated that promoter methylation was a key mechanism contributing to the downregulation of SAMD14 in GC. SAMD14 may be an epigenetically silenced tumor suppressor gene, and hyper-methylation of the SAMD14 promoter may serve as a biomarker to predict the clinical outcome of GC.


Assuntos
Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilação de DNA , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Repressoras/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
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