Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 59
Filtrar
1.
Front Psychol ; 15: 1364166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220399

RESUMO

How we view the passage of past time determines how we face time itself as well as our futures, which has a strong impact particularly during the highly creative and malleable college years. Chinese culture cherishes time deeply, and for centuries there has been a tradition of "educating children and youth to inspect the passage of time." However, in today's age of information and intelligence, time has shown a trend toward fragmentation. How do contemporary Chinese college students view the passage of time, and what structures or content does it contain? The answer to this question remains uncertain, necessitating further exploration. Following Flavell's theory of metacognitive knowledge (MK), we adopted a semi-structured interview method and used the results to first outline the basic structure of Chinese college students' view of time passing, identifying four major aspects: priming aftereffect, life touching, positive promotion, and negative inhibition. Then, using the initial four-dimensional structure as a starting point, we developed the Metacognitive Knowledge of Time Passing Scale (MKTPS), and carried out exploratory factor analysis and confirmatory factor analysis to test its fit. The results showed that the four-factor scale and its 22 items had a good fit to the data. Third, the reliability and validity of the self-developed scale were tested. The results show that the internal consistency, split-half, and retest reliability of the MKTPS are good (all rs > 0.60). The construct validity of the MKTPS is also good (r between subscales is 0.33-0.60, r between subscales and total scale is 0.64-0.87), the convergent validity with Zimbardo's negative past time perspective is high (r = 0.37), and the discriminant validity with Zimbardo's future time perspective is significant (r = 0.18). Regarding criterion correlation validity, the total scores of the MKTPS have a significantly higher positive correlation with those of the time management disposition (TMD) scale (r = 0.45). Future points for studying the view of time passing in adults of all ages and across cultures field and shortcomings of the current study are also discussed.

2.
Sci Rep ; 14(1): 18019, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39097676

RESUMO

Accurate, fast and lightweight dense target detection methods are highly important for precision agriculture. To detect dense apricot flowers using drones, we propose an improved dense target detection method based on YOLOv8, named D-YOLOv8. First, we introduce the Dense Feature Pyramid Networks (D-FPN) to enhance the model's ability to extract dense features and Dense Attention Layer (DAL) to focus on dense target areas, which enhances the feature extraction ability of dense areas, suppresses features in irrelevant areas, and improves dense target detection accuracy. Finally, RAW data are used to enhance the dataset, which introduces additional original data into RAW images, further enriching the feature input of dense objects. We perform validation on the CARPK challenge dataset and constructed a dataset. The experimental results show that our proposed D-YOLOv8m achieved 98.37% AP, while the model parameters were only 13.2 million. The improved network can effectively support any task of dense target detection.

3.
Nat Commun ; 15(1): 6704, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112454

RESUMO

Body heat, a clean and ubiquitous energy source, is promising as a renewable resource to supply wearable electronics. Emerging tough thermogalvanic device could be a sustainable platform to convert body heat energy into electricity for powering wearable electronics if its Carnot-relative efficiency (ηr) reaches ~5%. However, maximizing both the ηr and mechanical strength of the device are mutually exclusive. Here, we develop a rational strategy to construct a flexible thermogalvanic armor (FTGA) with a ηr over 8% near room temperature, yet preserving mechanical robustness. The key to our design lies in simultaneously realizing the thermosensitive-crystallization and salting-out effect in the elaborately designed ion-transport highway to boost ηr and improve mechanical strength. The FTGA achieves an ultrahigh ηr of 8.53%, coupling with impressive mechanical toughness of 70.65 MJ m-3 and substantial elongation (~900%) together. Our strategy holds sustainable potential for harvesting body heat and powering wearable electronics without recharging.

4.
Nat Commun ; 15(1): 4762, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834547

RESUMO

Liquid-solid contact electrification (CE) is essential to diverse applications. Exploiting its full implementation requires an in-depth understanding and fine-grained control of charge carriers (electrons and/or ions) during CE. Here, we decouple the electrons and ions during liquid-solid CE by designing binary superhydrophobic surfaces that eliminate liquid and ion residues on the surfaces and simultaneously enable us to regulate surface properties, namely work function, to control electron transfers. We find the existence of a linear relationship between the work function of superhydrophobic surfaces and the as-generated charges in liquids, implying that liquid-solid CE arises from electron transfer due to the work function difference between two contacting surfaces. We also rule out the possibility of ion transfer during CE occurring on superhydrophobic surfaces by proving the absence of ions on superhydrophobic surfaces after contact with ion-enriched acidic, alkaline, and salt liquids. Our findings stand in contrast to existing liquid-solid CE studies, and the new insights learned offer the potential to explore more applications.

5.
Am J Physiol Endocrinol Metab ; 326(6): E832-E841, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656129

RESUMO

Thyroid dysgenesis (TD) is the common pathogenic mechanism of congenital hypothyroidism (CH). In addition, known pathogenic genes are limited to those that are directly involved in thyroid development. To identify additional candidate pathogenetic genes, we performed forward genetic screening for TD in zebrafish, followed by positional cloning. The candidate gene was confirmed in vitro using the Nthy-ori 3.1 cell line and in vivo using a zebrafish model organism. We obtained a novel zebrafish line with thyroid dysgenesis and identified the candidate pathogenetic mutation TATA-box binding protein associated Factor 1 (taf1) by positional cloning. Further molecular studies revealed that taf1 was needed for the proliferation of thyroid follicular cells by binding to the NOTCH1 promoter region. Knockdown of TAF1 impaired the proliferation and maturation of thyroid cells, thereby leading to thyroid dysplasia. This study showed that TAF1 promoted Notch signaling and that this association played a pivotal role in thyroid development.NEW & NOTEWORTHY In our study, we obtained a novel zebrafish line with thyroid dysgenesis (TD) and identified the candidate pathogenetic mutation TATA-box binding protein associated Factor 1 (taf1). Further researches revealed that taf1 was required for thyroid follicular cells by binding to the NOTCH1 promoter region. Our findings revealed a novel role of TAF1 in thyroid morphogenesis.


Assuntos
Proliferação de Células , Transdução de Sinais , Fatores Associados à Proteína de Ligação a TATA , Glândula Tireoide , Fator de Transcrição TFIID , Peixe-Zebra , Animais , Proliferação de Células/genética , Histona Acetiltransferases , Receptor Notch1/genética , Receptor Notch1/metabolismo , Transdução de Sinais/genética , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Disgenesia da Tireoide/genética , Disgenesia da Tireoide/metabolismo , Glândula Tireoide/metabolismo , Fator de Transcrição TFIID/genética , Fator de Transcrição TFIID/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
6.
Appl Opt ; 63(9): 2234-2240, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38568577

RESUMO

Bessel beam arrays are highly attractive due to non-diffraction properties, parallel processing, and large capacity capabilities. However, conventional approaches of generating Bessel beams, such as spatial light modulators, axicons, and diffraction optical elements, suffer from various limitations of system complexity and bulkiness, low uniformity, and limited numerical aperture (NA). The limited NA imposes constraints on achieving minimal full width at half maximum (FWHM) of the Bessel beam, ultimately compromising the resolution of the beam. In this study, we demonstrate a method for generating Bessel beam arrays with regular and random patterns via an ultra-compact metasurface. This approach integrates the phase profile of an optimized beam splitter with a meta-axicon. The Bessel beam arrays exhibit subwavelength dimensions of FWHM (590 nm, ∼0.9λ) and relatively high uniformity of 90% for N A=0.2 and 69% for N A=0.4. Furthermore, the method achieves effective suppression of background noise and zeroth-order intensity compared to methods based on Dammann grating (DG) based metasurfaces. The proposed method highlights potential applications of Bessel beam arrays in various fields, such as laser machining, optical communication, and biomedical imaging.

7.
ACS Omega ; 9(14): 16621-16630, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617651

RESUMO

Transition metal oxides are efficient bifunctional catalysts for the selective catalytic reduction (SCR) of nitrogen oxides (NOx) using CO. Nonetheless, their poor activity at lower temperatures constrains broader industrial application. Herein, we propose an optimized Fe2O3-based catalyst through strategic metal doping with Cu, Co, or Ce, which engenders a harmonious balance for the synergistic removal of CO and NOx. Among the developed catalysts, Co-doped Fe2O3, supported by rice husk ash, demonstrates superior low-temperature CO-SCR activity, achieving CO and NOx conversion ratios and N2 selectivity above 98.5% at 100-500 °C. The enhanced catalytic performance is attributed to the catalyst's improved redox properties and acidity, engendered by strong Fe-Ox-Co interactions. Furthermore, the CO-SCR reaction adheres to the Langmuir-Hinshelwood and Eley-Rideal mechanisms. Our findings shed light on the future industrial application of low-temperature CO and NOx near-zero emission technology and provide a strategy for the design of low-cost SCR catalysts.

8.
Ann Lab Med ; 44(4): 343-353, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38433572

RESUMO

Background: Genetic defects in the human thyroid-stimulating hormone (TSH) receptor (TSHR) gene can cause congenital hypothyroidism (CH). However, the biological functions and comprehensive genotype-phenotype relationships for most TSHR variants associated with CH remain unexplored. We aimed to identify TSHR variants in Chinese patients with CH, analyze the functions of the variants, and explore the relationships between TSHR genotypes and clinical phenotypes. Methods: In total, 367 patients with CH were recruited for TSHR variant screening using whole-exome sequencing. The effects of the variants were evaluated by in-silico programs such as SIFT and polyphen2. Furthermore, these variants were transfected into 293T cells to detect their Gs/cyclic AMP and Gq/11 signaling activity. Results: Among the 367 patients with CH, 17 TSHR variants, including three novel variants, were identified in 45 patients, and 18 patients carried biallelic TSHR variants. In vitro experiments showed that 10 variants were associated with Gs/cyclic AMP and Gq/11 signaling pathway impairment to varying degrees. Patients with TSHR biallelic variants had lower serum TSH levels and higher free triiodothyronine and thyroxine levels at diagnosis than those with DUOX2 biallelic variants. Conclusions: We found a high frequency of TSHR variants in Chinese patients with CH (12.3%), and 4.9% of cases were caused by TSHR biallelic variants. Ten variants were identified as loss-of-function variants. The data suggest that the clinical phenotype of CH patients caused by TSHR biallelic variants is relatively mild. Our study expands the TSHR variant spectrum and provides further evidence for the elucidation of the genetic etiology of CH.


Assuntos
Hipotireoidismo Congênito , Humanos , China , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/genética , AMP Cíclico , Oxidases Duais/genética , Mutação , Fenótipo , Receptores da Tireotropina/genética , Tireotropina
9.
Trends Pharmacol Sci ; 45(3): 268-280, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38296675

RESUMO

Olfactory receptors (ORs) form the most important chemosensory receptor family responsible for our sense of smell in the nasal olfactory epithelium. This receptor family belongs to the class A G protein-coupled receptors (GPCRs). Recent research has indicated that ORs are involved in many nonolfactory physiological processes in extranasal tissue, such as the brain, pancreas, and testes, and implies the possible role of their dysregulation in various diseases. The recently released structures of OR51E2 and consensus OR52 have also unveiled the uniqueness of ORs from other class A GPCR members. In this review, we discuss these recent developments and computational modeling efforts toward understanding the structural properties of unresolved ORs, which could guide potential future OR-targeted drug discovery.


Assuntos
Receptores Odorantes , Humanos , Receptores Odorantes/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Olfato , Descoberta de Drogas , Encéfalo/metabolismo , Proteínas de Neoplasias
10.
Cytokine ; 175: 156480, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38232644

RESUMO

Cutaneous squamous cell carcinoma (CSCC) is the second most common malignant skin tumor and significantly affects patients' quality of life and health. The Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) pathway activation is involved in CSCC development. Radix Tetrastigma hemsleyani flavone (RTHF) is an active Radix Tetrastigma extract (RTE), which was recently reported to have promising inhibitory effects on CSCC. However, the underlying functional mechanisms of this inhibition remain unknown. In the present study, A431 cells or SCL-1 cells were incubated with 1, 5, and 10 mg/mL RTHF for 48 h, respectively. A significantly increased wound closure rate, decreased number of migrated and invaded cells, decreased colony number, and elevated apoptotic rate were observed after treatment with 1, 5, and 10 mg/mL RTHF. Furthermore, after incubation with RTHF, p-JAK1/JAK1, p-JAK2/JAK2, and p-STAT3/STAT3 levels were drastically reduced. An A431 xenograft model was constructed, followed by oral administration of 15, 30, or 60 mg/kg RTHF for 21 consecutive days. A significantly lower increase in tumor volume and reduced tumor weight were observed in all RTHF-treated groups. In addition, JAK/STAT3 signaling was drastically repressed in tumor tissues. Collectively, RTHF inhibited CSCC progression, which may be associated with JAK/STAT3 pathway inactivation.


Assuntos
Carcinoma de Células Escamosas , Flavonas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/patologia , Janus Quinases/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Fator de Transcrição STAT3/metabolismo , Qualidade de Vida , Proliferação de Células , Linhagem Celular Tumoral , Flavonas/farmacologia , Flavonas/uso terapêutico , Apoptose
11.
Thyroid ; 34(3): 324-335, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38183624

RESUMO

Background: Congenital hypothyroidism (CH) is the most common neonatal metabolic disorder. In patients with CH in China, thyroid dyshormonogenesis is more common than thyroid dysgenesis; however, the genetic causes of CH due to thyroid dyshormonogenesis remain largely unknown. Therefore, we aimed at identifying novel candidate causative genes for CH. Methods: To identify novel CH candidate genes, a total of 599 patients with CH were enrolled and next-generation sequencing was performed. The functions of the identified variants were confirmed using HEK293T and FTC-133 cell lines in vitro and in a mouse model organism in vivo. Results: Three pathogenic contactin 6 (CNTN6) variants were identified in two patients with CH. Pedigree analysis showed that CH caused by CNTN6 variants was inherited in an autosomal recessive pattern. The CNTN6 gene was highly expressed in the thyroid in humans and mice. Cntn6 knockout mice presented with thyroid dyshormonogenesis and CH due to the decreased expression of crucial genes for thyroid hormone biosynthesis (Slc5a5, Tpo, and Duox2). All three CNTN6 variants resulted in the blocking of the release of the Notch intracellular domain, which could not translocate into the nucleus, impaired NOTCH1 transcriptional activity, and decreased expression of SLC5A5, TPO, and DUOX2. Further, we found that DTX1 was required for CNTN6 to promote thyroid hormone biosynthesis through Notch signaling. Conclusions: This study demonstrated that CNTN6 is a novel causative gene for CH through the mediation of thyroid hormone biosynthesis via Notch signaling, which provides new insights into the genetic background and mechanisms involved in CH and thyroid dyshormonogenesis.


Assuntos
Hipotireoidismo Congênito , Humanos , Animais , Camundongos , Hipotireoidismo Congênito/genética , Oxidases Duais/genética , Células HEK293 , Mutação , Iodeto Peroxidase/genética , Hormônios Tireóideos , Contactinas/genética
12.
Cell Prolif ; 57(2): e13540, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814474

RESUMO

Derivation of human hepatocytes from pluripotent stem cells in vitro has important applications including cell therapy and drug discovery. However, the differentiation of pluripotent stem cells into hepatocytes in vitro was not well recapitulated the development of liver. Here, we developed a differentiation protocol by mimicking the two-stage development of hepatoblasts, which permits the efficient generation of hepatic progenitor cells from chemically induced pluripotent stem cells (hCiPSCs). Single-cell RNA sequencing (scRNA-seq) indicates the similarity between hepatoblasts differentiated in vitro and in vivo. Moreover, hCiPSC-derived hepatic progenitor cells can further differentiate into hepatocytes that are similar to primary human hepatocytes with respect to gene expression and key hepatic functions. Our results demonstrate the feasibility of generating hepatic progenitor cells and hepatocytes from hCiPSCs with high efficiency and set the foundation for broad translational applications of hCiPSC-derived hepatocytes.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Hepatócitos/metabolismo , Fígado/metabolismo , Diferenciação Celular
13.
Free Radic Biol Med ; 210: 304-317, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38042222

RESUMO

Persistent oxidative stress and endoplasmic reticulum (ER) stress are the primary mechanisms of age-related cardiovascular diseases. Although exercise training is viewed as an effective anti-aging approach, further exploration is needed to identify the mechanisms and functional targets. In this study, the impact of resistance training (RT) on the expression of Smyd1, the levels of reactive oxygen species (ROS) and the expression of ER stress-related protein in the hearts of mice of different ages were assessed. In addition, the role of Smyd1 in the aging-induced oxidative stress and ER stress were evaluated in d-galactose (D-gal)-treated H9C2 cells. We demonstrated that RT in middle age increased the expression of Smyd1 and restricted heart aging-induced ER stress. Overexpression of Smyd1 restrained oxidative stress and ER stress in D-gal-treated H9C2 cells, while the inhibition of Nrf2 and Smyd1 escalated ER stress. These findings demonstrate that Smyd1 has significant impact in regulating age-related ER stress. RT in middle age can up-regulates Smyd1 expression and inhibits oxidative stress and ER stress in the heart.


Assuntos
Treinamento Resistido , Humanos , Camundongos , Animais , Coração , Estresse do Retículo Endoplasmático/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Proteínas de Ligação a DNA/metabolismo , Proteínas Musculares/metabolismo , Fatores de Transcrição/metabolismo
14.
PLoS One ; 18(11): e0294186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37956159

RESUMO

The "live streaming + charity" model is a new model for China's philanthropy, accelerating the new development of China's philanthropy, but there is still a relative paucity of research in the academic community on how charity live streaming affects online charitable donations. In this sense, this study aims to identify the construction of a model of the factors influencing charity live streaming on online charitable donations. This study selected TikTok Live, based on the UTAUT model, combining perceived risk and perceived interactivity, recovered 607 valid questionnaires, and concluded and structural equation modeling to construct an influence factor model to analyze their correlation. The results show that users' performance expectancy, effort expectancy, perceived interactivity, facilitating conditions, and social influence are significantly positively correlated with online charitable donations, and perceived risk does not negatively affect users' intentions to make online charitable donations. Our findings can provide a basis for live-streaming platforms and relevant social organizations and government departments to develop charity communication strategies.


Assuntos
Instituições de Caridade , Mídias Sociais , Pesquisa Empírica , Comunicação , Órgãos Governamentais
15.
Small ; : e2304635, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37786271

RESUMO

Rapid detachment of impacting droplets from underlying substrate is highly preferred for mass, momentum, and energy exchange in many practical applications. Driven by this, the past several years have witnessed a surge in engineering macrotexture to reduce solid-liquid contact time. Despite these advances, these strategies in reducing contact time necessitate the elegant control of either the spatial location for droplet contact or the range of impacting velocity. Here, this work circumvents these limitations by designing a dual gradient surface consisting of a vertical spacing gradient made of tapered pillar arrays and a lateral curvature gradient characterized as macroscopic convex. This design enables the impacting droplets to self-adapt to asymmetric or pancake bouncing mode accordingly, which renders significant contact time reduction (up to ≈70%) for a broad range of impacting velocities (≈0.4-1.4 m s-1 ) irrespective of the spatial impacting location. This new design provides a new insight for designing liquid-repellent surfaces, and offers opportunities for applications including dropwise condensation, energy conversion, and anti-icing.

16.
Nat Commun ; 14(1): 6855, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891172

RESUMO

Highly reflective surfaces are notorious in the field of depth sensing and three-dimensional (3D) imaging because they can cause severe errors in perception of the depth. Despite recent progress in addressing this challenge, there are still no robust and error-free solutions. Here, we devise a polarization structured light 3D sensor for solving these problems, in which high-contrast-grating (HCG) vertical-cavity surface-emitting lasers (VCSELs) are used to exploit the polarization property. We demonstrate accurate depth measurements of the reflective surfaces and objects behind them in various imaging situations. In addition, the absolute error and effective measurement range are measured to prove the applicability for a wide range of 3D applications. Our work innovatively combines polarization and depth information, opening the way for fully understanding and applying polarization properties in the 3D domain.

17.
Horm Res Paediatr ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703865

RESUMO

INTRODUCTION: Congenital hypothyroidism (CH), the most common neonatal endocrine disorder world-wide, can be caused by variants in the thyroid peroxidase (TPO) gene. This study aimed to identify TPO variants in Chinese patients with CH, analyze their impact on TPO function, and establish relationships between TPO genotypes and clinical characteristics. METHODS: A total of 328 patients with CH were screened for TPO variants by performing whole exome sequencing. The function of the detected TPO variants was investigated via transfection assays in vitro. The pathogenic effect of five novel variants was further assessed in silico. RESULTS: Among 328 patients with CH, 19 TPO variants, including six novel ones, were identified in 43 patients. Eighteen patients (5.5%) carried biallelic TPO variants. In vitro experiments showed that TPO activity was impaired to varying degrees in 17 variants. Furthermore, we determined that a residual TPO enzyme activity threshold of 15% may serve as a criterion for differentiating CH severity. CONCLUSIONS: According to our study, the prevalence of TPO variants among Chinese patients with CH was 13.1 %. Five novel variants led to impaired TPO function by altering its structure or by affecting its expression or cellular localization, which should result in impaired thyroid hormone synthesis.

18.
Small ; 19(52): e2304218, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37649201

RESUMO

Superhydrophobic and slippery lubricant-infused surfaces have garnered significant attention for their potential to passively transport low-viscosity liquids like water (1 mPa s). Despite exciting progress, these designs have proven ineffective for transporting high-viscosity liquids such as polydimethylsiloxane (5500 mPa s) due to their inherent limitations imposed by the homogenous surface design, resulting in high viscous drags and compromised capillary forces. Here, a heterogenous water-infused divergent surface (WIDS) is proposed that achieves spontaneous, rapid, and long-distance transport of viscous liquids. WIDS reduces viscous drag by spatially isolating the viscous liquids and surface roughness through its heterogenous, slippery topological design, and generates capillary forces through its heterogenous wetting distributions. The essential role of surface heterogeneity in viscous liquid transport is theoretically and experimentally verified. Remarkably, such a heterogenous paradigm enables transporting liquids with viscosities exceeding 12 500 mPa s, which is two orders of magnitude higher than state-of-the-art techniques. Furthermore, this heterogenous design is generic for various viscous liquids and can be made flexible, making it promising for various systems that require viscous liquid management, such as micropatterning.

19.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446006

RESUMO

The pathogenesis of ulcerative colitis (UC) is associated with inflammation, oxidative stress, and gut microbiota imbalance. Although most researchers have demonstrated the antioxidant bioactivity of the phenolic compounds in plants, their UC-curing ability and underlying mechanisms still need to be further and adequately explored. Herein, we studied the antioxidation-structure relationship of several common polyphenols in plants including gallic acid, proanthocyanidin, ellagic acid, and tannic acid. Furthermore, the in vivo effects of the plant polyphenols on C57BL/6 mice with dextran-sulfate-sodium-induced UC were evaluated and the action mechanisms were explored. Moreover, the interplay of several mechanisms was determined. The higher the number of phenolic hydroxyl groups, the stronger the antioxidant activity. All polyphenols markedly ameliorated the symptoms and pathological progression of UC in mice. Furthermore, inflammatory cytokine levels were decreased and the intestinal barrier was repaired. The process was regulated by the antioxidant-signaling pathway of nuclear-erythroid 2-related factor 2. Moreover, the diversity of the intestinal microbiota, Firmicutes-to-Bacteroides ratio, and relative abundance of beneficial bacteria were increased. An interplay was observed between microbiota regulation and oxidative stress, immunity, and inflammatory response. Furthermore, intestinal barrier repair was found to be correlated with inflammatory responses. Our study results can form a basis for comprehensively developing plant-polyphenol-related medicinal products.


Assuntos
Colite Ulcerativa , Microbiota , Animais , Camundongos , Camundongos Endogâmicos C57BL , Antioxidantes/farmacologia , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Fenóis
20.
Front Pharmacol ; 14: 1184183, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408766

RESUMO

Introduction: Inflammatory bowel disease (IBD) affects about 7 million people globally, which is a chronic inflammatory condition of the gastrointestinal tract caused by gut microbiota alterations, immune dysregulation, genetic and environmental factors. Nanoparticles (NPs) deliver an active natural compound to a site harbored by disordered microbiota, they are used to interact, target and act intentionally on microbiota. Although there is accumulating evidence indicating that berberine and polysaccharide play an important role in IBD via regulating microbiota, there is limited research that presents a complete picture of exactly how their carrier-free co-assembled nanodrug affects IBD. Methods: The study establishes the carrier-free NPs formed by berberine and rhubarb polysaccharide based on the combination theory of Rheum palmatum L. and Coptis chinensis Franch., and characterizes the NPs. The IBD treatment efficacy of NPs are evaluated via IBD efficacy index, and explore the mechanism of NPs via 16S rRNA test and immunohistochemistry including occludin and zonula occludens-1. Results: The results showed that DHP and BBR were co-assembled to nanoparticles, and the BD can effectively relieve the symptoms of UC mouse induced by DSS via regulating gut microbiota and repair the gut barrier integrity, because BD have a longer retention on the colon tissue and react with the microbiota and mucus thoroughly. Interestingly, BD can enrich more probiotic than free BBR and DHP. Discussion: This design provides a better strategy and encourages future studies on IBD treatment via regulating gut microbiota and the design of novel plant polysaccharide based carrier-free co-assembly therapies.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA