Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 402
Filtrer
2.
Zhen Ci Yan Jiu ; 49(7): 678-685, 2024 Jul 25.
Article de Anglais, Chinois | MEDLINE | ID: mdl-39020485

RÉSUMÉ

OBJECTIVES: To investigate the impact of combined treatment of colorectal cancer (CRC) with electroacupuncture (EA) and capeOX (combined administration of fluorouracil, oxaliplatin and capecitabine) on the tumor volume, weight, spleen coefficient, apoptosis and ferroptosis of tumor tissue, and liver and kidney functions in nude mice with CRC, so as to explore its mechanisms underlying inhibiting CRC and alleviating toxic reactions of capeOX. METHODS: Female Balb/c nude mice were randomly assigned to 3 groups:model, capeOX, and EA+capeOX, with 8 nude mice in each group. The CRC model was established by subcutaneous injection of colon cancer cells at the right inguinal region. Nude mice of the capeOX group received intraperitoneal injection of oxaliplatin for 1 day and gavage of capecitabine from day 2 to day 7. EA (1 mA, 2 Hz/100 Hz) was applied to bilateral "Zusanli" (ST36) for 20 min, once daily for 7 days. During the interven-tion, the tumor volume and weight were measured every day, and at the end of intervention, the weight of the tumor tissue and spleen were measured, with tumor volume difference and spleen coefficient calculated. The proportion of apoptotic cells was measured by flow cytometry, and the contents of serum malondialdehyde (MDA), alanine aninotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), and creatinine (Cr) were detected using ELISA. The expression level of glutathione peroxidase 4 (GPX4, a key regulator for ferroptosis) protein of the tumor tissue was determined using Western blot. RESULTS: Compared to the model group, both the capeOX group and EA+capeOX group showed a decrease in the tumor volume (on day 3 and 4 in the capeOX group, and from day 2 to 7 in the EA+capeOX group) and body weight (P<0.05, on day 3 to 7 in the EA+capeOX group and on day 2 to 7 in the capeOX group), being evidently lower in the tumor volume on day 7 in the EA+capeOX than in the capeOX group (P<0.05), and evidently higher in the body weight on day 6 and 7 in the EA+capeOX group than in the capeOX group (P<0.05). In comparison with the model group, the tumor volume difference, tumor weight and spleen coefficient in both capeOX and EA+capeOX groups were significantly decreased (P<0.05), and MDA content in EA+capeOX group was significantly decreased (P<0.05), while the contents of ALT, BUN and Cr in the capeOX group, the proportion of apoptotic cells in both capeOX and EA+capeOX groups, and the GPX4 expression level in the EA+capeOX group were all significantly increased (P<0.05). The tumor volume difference, tumor weight, and contents of MDA, ALT, AST, BUN and Cr in the EA+capeOX group were markedly lower than in the capeOX group (P<0.05), while the spleen coefficient, proportion of apoptotic cells and GPX4 expression level in the EA+capeOX group were markedly higher than those in the capeOX group (P<0.05). CONCLUSIONS: EA of ST36 can enhance the effect of capeOX in inhibiting colorectal cancer growth in nude mice with CRC, which may be related with its functions in promoting tumor cell apoptosis, inhibiting ferroptosis, and modulating immune tolerance. In addition, EA can lower the side effects of capeOX in hematopoietic and immune, liver, and kidney functions.


Sujet(s)
Points d'acupuncture , Apoptose , Tumeurs colorectales , Électroacupuncture , Ferroptose , Souris de lignée BALB C , Souris nude , Animaux , Souris , Ferroptose/effets des médicaments et des substances chimiques , Humains , Apoptose/effets des médicaments et des substances chimiques , Tumeurs colorectales/thérapie , Tumeurs colorectales/métabolisme , Tumeurs colorectales/traitement médicamenteux , Femelle , Phospholipid hydroperoxide glutathione peroxidase/métabolisme , Phospholipid hydroperoxide glutathione peroxidase/génétique
4.
Endocrinology ; 165(8)2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38946397

RÉSUMÉ

Uterine leiomyoma or fibroids are prevalent noncancerous tumors of the uterine muscle layer, yet their origin and development remain poorly understood. We analyzed RNA expression profiles of 15 epigenetic mediators in uterine fibroids compared to myometrium using publicly available RNA sequencing (RNA-seq) data. To validate our findings, we performed RT-qPCR on a separate cohort of uterine fibroids targeting these modifiers confirming our RNA-seq data. We then examined protein profiles of key N6-methyladenosine (m6A) modifiers in fibroids and their matched myometrium, showing no significant differences in concordance with our RNA expression profiles. To determine RNA modification abundance, mRNA and small RNA from fibroids and matched myometrium were analyzed by ultra-high performance liquid chromatography-mass spectrometry identifying prevalent m6A and 11 other known modifiers. However, no aberrant expression in fibroids was detected. We then mined a previously published dataset and identified differential expression of m6A modifiers that were specific to fibroid genetic subtype. Our analysis also identified m6A consensus motifs on genes previously identified to be dysregulated in uterine fibroids. Overall, using state-of-the-art mass spectrometry, RNA expression, and protein profiles, we characterized and identified differentially expressed m6A modifiers in relation to driver mutations. Despite the use of several different approaches, we identified limited differential expression of RNA modifiers and associated modifications in uterine fibroids. However, considering the highly heterogenous genomic and cellular nature of fibroids, and the possible contribution of single molecule m6A modifications to fibroid pathology, there is a need for greater in-depth characterization of m6A marks and modifiers in a larger and diverse patient cohort.


Sujet(s)
Adénosine , Léiomyome , Tumeurs de l'utérus , Léiomyome/génétique , Léiomyome/métabolisme , Humains , Femelle , Adénosine/analogues et dérivés , Adénosine/métabolisme , Tumeurs de l'utérus/génétique , Tumeurs de l'utérus/métabolisme , Tumeurs de l'utérus/anatomopathologie , Myomètre/métabolisme , Myomètre/anatomopathologie , Adulte d'âge moyen , Adulte , ARN messager/métabolisme , ARN messager/génétique , ARN/génétique , ARN/métabolisme , Maturation post-transcriptionnelle des ARN , Épigenèse génétique
5.
Ying Yong Sheng Tai Xue Bao ; 35(4): 917-925, 2024 Apr 18.
Article de Chinois | MEDLINE | ID: mdl-38884226

RÉSUMÉ

Biological nitrogen (N) fixation is an important source of N in terrestrial ecosystems, but the response of soil microbial N fixation rate to N deposition in different forest ecosystems still remains uncertain. We conducted a field N addition experiment to simulate atmosphere N deposition in subtropical Pinus taiwanensis and Castanopsis faberi forests. We set up three levels of nitrogen addition using urea as the N source: 0 (control), 40 (low N), and 80 g N·hm-2·a-1(high N) to examine the chemical properties, microbial biomass C, enzyme activities, and nifH gene copies of top soils (0-10 cm). We also measured the microbial N fixation rate using the 15N labeling method. Results showed that N addition significantly reduced the soil microbial N fixation rate in the P. taiwanensis and C. faberi forests by 29%-33% and 10%-18%, respectively. Nitrogen addition significantly reduced N-acquiring enzyme (i.e., ß-1, 4-N-acetylglucosaminidase) activity and nifH gene copies in both forest soils. There was a significant positive correlation between the microbial N fixation rate and soil dissolved organic C content in the P. taiwanensis forest, but a significant negative relationship between the rate of soil microbial nitrogen fixation and NH4+-N content in the C. faberi forest. Overall, soil microbial N fixation function in the P. taiwanensis forest was more sensitive to N addition than that in the C. faberi forest, and the factors affecting microbial N fixation varied between the two forest soils. The study could provide insights into the effects of N addition on biological N fixation in forest ecosystems, and a theoretical basis for forest management.


Sujet(s)
Forêts , Fixation de l'azote , Azote , Pinus , Microbiologie du sol , Azote/métabolisme , Azote/analyse , Pinus/croissance et développement , Pinus/métabolisme , Sol/composition chimique , Fagaceae/croissance et développement , Chine , Climat tropical
6.
Bone Res ; 12(1): 31, 2024 May 23.
Article de Anglais | MEDLINE | ID: mdl-38782893

RÉSUMÉ

Rheumatoid arthritis (RA) is an autoimmune disease. Early studies hold an opinion that gut microbiota is environmentally acquired and associated with RA susceptibility. However, accumulating evidence demonstrates that genetics also shape the gut microbiota. It is known that some strains of inbred laboratory mice are highly susceptible to collagen-induced arthritis (CIA), while the others are resistant to CIA. Here, we show that transplantation of fecal microbiota of CIA-resistant C57BL/6J mice to CIA-susceptible DBA/1J mice confer CIA resistance in DBA/1J mice. C57BL/6J mice and healthy human individuals have enriched B. fragilis than DBA/1J mice and RA patients. Transplantation of B. fragilis prevents CIA in DBA/1J mice. We identify that B. fragilis mainly produces propionate and C57BL/6J mice and healthy human individuals have higher level of propionate. Fibroblast-like synoviocytes (FLSs) in RA are activated to undergo tumor-like transformation. Propionate disrupts HDAC3-FOXK1 interaction to increase acetylation of FOXK1, resulting in reduced FOXK1 stability, blocked interferon signaling and deactivation of RA-FLSs. We treat CIA mice with propionate and show that propionate attenuates CIA. Moreover, a combination of propionate with anti-TNF etanercept synergistically relieves CIA. These results suggest that B. fragilis or propionate could be an alternative or complementary approach to the current therapies.


Sujet(s)
Arthrite expérimentale , Polyarthrite rhumatoïde , Microbiome gastro-intestinal , Histone deacetylases , Souris de lignée C57BL , Cellules synoviales , Animaux , Humains , Mâle , Souris , Arthrite expérimentale/anatomopathologie , Arthrite expérimentale/métabolisme , Polyarthrite rhumatoïde/métabolisme , Polyarthrite rhumatoïde/anatomopathologie , Polyarthrite rhumatoïde/traitement médicamenteux , Polyarthrite rhumatoïde/microbiologie , Fibroblastes/métabolisme , Fibroblastes/effets des médicaments et des substances chimiques , Facteurs de transcription Forkhead/métabolisme , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Histone deacetylases/métabolisme , Souris de lignée DBA , Transduction du signal/effets des médicaments et des substances chimiques , Cellules synoviales/métabolisme , Cellules synoviales/effets des médicaments et des substances chimiques , Cellules synoviales/anatomopathologie
7.
Aging Dis ; 2024 Apr 25.
Article de Anglais | MEDLINE | ID: mdl-38739938

RÉSUMÉ

S-Nitrosylation is a reversible covalent post-translational modification. Under physiological conditions, S-nitrosylation plays a dynamic role in a wide range of biological processes by regulating the function of substrate proteins. Like other post-translational modifications, S-nitrosylation can affect protein conformation, activity, localization, aggregation, and protein interactions. Aberrant S-nitrosylation can lead to protein misfolding, mitochondrial fragmentation, synaptic damage, and autophagy. Mitochondria are essential organelles in energy production, metabolite biosynthesis, cell death, and immune responses, among other processes. Mitochondrial dysfunction can result in cell death and has been implicated in the development of many human diseases. Recent evidence suggests that S-nitrosylation and mitochondrial dysfunction are important modulators of the progression of several diseases. In this review, we highlight recent findings regarding the aberrant S- nitrosylation of mitochondrial proteins that regulate mitochondrial biosynthesis, fission and fusion, and autophagy. Specifically, we discuss the mechanisms by which S-nitrosylated mitochondrial proteins exercise mitochondrial quality control under pathological conditions, thereby influencing disease. A better understanding of these pathological events may provide novel therapeutic targets to mitigate the development of neurological diseases.

8.
Oral Dis ; 2024 May 12.
Article de Anglais | MEDLINE | ID: mdl-38735833

RÉSUMÉ

BACKGROUND: Diabetes is accompanied by a high prevalence of hyposalivation, causing severe damage to oral and systemic health. Mitochondrial dynamics play important roles in the pathogenesis of various diabetic complications; however, little is known about their roles in diabetic hyposalivation. MATERIALS AND METHODS: A diabetic mouse model and a high glucose (HG)-induced diabetic submandibular gland (SMG) cell model were employed. RESULTS: More mitochondria surrounded by autophagosomes and higher expression of mitophagy-related proteins were detected in the SMGs of diabetic mice and HG-treated SMG cells. In diabetic SMGs, dynamin-related protein 1 (DRP1) was upregulated, whereas mitofusin-2 was downregulated both in vivo and in vitro. Shortened mitochondria and impaired mitochondrial functions were observed in the HG group. A DRP1-specific inhibitor, mdivi-1, suppressed mitochondrial fission and mitophagy, as well as restored mitochondrial functions in the HG condition. Moreover, the interaction of F-actin and DRP1 was enhanced in the diabetic group. Inhibiting F-actin with cytochalasin D repaired the injured effects of HG on mitochondrial dynamics and functions. Conversely, the F-actin-polymerization-inducer jasplakinolide aggravated mitochondrial fission and dysfunction. CONCLUSIONS: F-actin contributes to HG-evoked mitochondrial fission by interacting with DRP1, which induces mitophagy and impairs mitochondrial function in SMG cells, ultimately damaging the SMG.

9.
Cell Chem Biol ; 31(7): 1290-1304.e7, 2024 Jul 18.
Article de Anglais | MEDLINE | ID: mdl-38657608

RÉSUMÉ

Proteolysis-targeting chimeras (PROTACs) are heterobifunctional molecules consisting of two ligands joined by a linker, enabling them to simultaneously bind with an E3 ligase and a protein of interest (POI) and trigger proteasomal degradation of the POI. Limitations of PROTAC include lack of potent E3 ligands, poor cell selectivity, and low permeability. AS1411 is an antitumor aptamer specifically recognizing a membrane-nucleus shuttling nucleolin (NCL). Here, we repurpose AS1411 as a ligand for an E3 ligase mouse double minute 2 homolog (MDM2) via anchoring the NCL-MDM2 complex. Then, we construct an AS1411-NCL-MDM2-based PROTAC (ANM-PROTAC) by conjugating AS1411 with large-molecular-weight ligands for "undruggable" oncogenic STAT3, c-Myc, p53-R175H, and AR-V7. We show that the ANM-PROTAC efficiently penetrates tumor cells, recruits MDM2 and degrades the POIs. The ANM-PROTAC achieves tumor-selective distribution and exhibits excellent antitumor activity with no systemic toxicity. This is a PROTAC with built-in tumor-targeting and cell-penetrating capacities.


Sujet(s)
Antinéoplasiques , Aptamères nucléotidiques , Protéolyse , Protéines proto-oncogènes c-mdm2 , Humains , Protéines proto-oncogènes c-mdm2/métabolisme , Protéines proto-oncogènes c-mdm2/antagonistes et inhibiteurs , Animaux , Souris , Protéolyse/effets des médicaments et des substances chimiques , Aptamères nucléotidiques/composition chimique , Aptamères nucléotidiques/pharmacologie , Aptamères nucléotidiques/métabolisme , Antinéoplasiques/pharmacologie , Antinéoplasiques/composition chimique , Antinéoplasiques/synthèse chimique , Ligands , , Protéines de liaison à l'ARN/métabolisme , Repositionnement des médicaments , Femelle , Souris nude , Prolifération cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Souris de lignée BALB C , Phosphoprotéines/métabolisme , Phosphoprotéines/antagonistes et inhibiteurs , Phosphoprotéines/composition chimique , Tests de criblage d'agents antitumoraux , Chimère ciblant la protéolyse , Oligodésoxyribonucléotides
11.
Acta Cytol ; 68(2): 137-144, 2024.
Article de Anglais | MEDLINE | ID: mdl-38527422

RÉSUMÉ

INTRODUCTION: Methylation assays have demonstrated potential as dependable and high-precision approaches for identifying or triaging individuals with cervical cancer (CA) or cervical intraepithelial neoplasia (CIN). Our investigation aimed to assess the efficacy of the diagnosis and triage of the PAX1/SOX1 methylation panel in detecting CIN or CA. METHODS: A total of 461 patients with abnormal high-risk human papillomavirus (hrHPV) or cytology test results were recruited for this study. Each patient underwent an assortment of assessments, comprising a cytology test, hrHPV test, colposcopy examination, and PAX1 and SOX1 methylation tests. RESULTS: The extent of methylation of both genes demonstrates a positive correlation with the severity of CIN lesions and CA. To determine the correlation for patients with CIN2 or worse (CIN2+), the area under curve was 0.821 (95% CI: 0.782-0.853) for PAX1 and 0.800 (95% CI: 0.766-0.838) for SOX1, while for CIN3 or worse (CIN3+), 0.881 (95% CI: 0.839-0.908) for PAX1 and 0.867 (95% CI: 0.830-0.901) for SOX1. The PAX1/SOX1 methylation marker panel performed sensitivity and specificity of 77.16% and 91.67% for CIN2+, 84.76% and 90.50% for CIN3+, respectively. Regarding triaging hrHPV+ patients, the PAX1/SOX1 methylation test only referred 11.83% of the patients who are unnecessary for colonoscopy examination, which is comparatively lower than cytology, thereby signifying a promising triage strategy for hrHPV-positive women. Furthermore, we observed that the positive PAX1/SOX1 methylation test result for untreated CIN1 or fewer patients would result in a higher likelihood of progression upon a 24-month follow-up visit. CONCLUSION: The present investigation demonstrates that the PAX1/SOX1 methylation marker panel exhibits favorable diagnostic performance in CIN detection and holds the potential to be employed for individual CIN tests or hrHPV-positive triage.


Sujet(s)
Marqueurs biologiques tumoraux , Méthylation de l'ADN , Facteurs de transcription PAX , Facteurs de transcription SOX-B1 , Triage , Dysplasie du col utérin , Tumeurs du col de l'utérus , Humains , Femelle , Dysplasie du col utérin/diagnostic , Dysplasie du col utérin/génétique , Dysplasie du col utérin/virologie , Dysplasie du col utérin/anatomopathologie , Tumeurs du col de l'utérus/diagnostic , Tumeurs du col de l'utérus/génétique , Tumeurs du col de l'utérus/virologie , Tumeurs du col de l'utérus/anatomopathologie , Adulte , Facteurs de transcription PAX/génétique , Marqueurs biologiques tumoraux/génétique , Adulte d'âge moyen , Facteurs de transcription SOX-B1/génétique , Triage/méthodes , Colposcopie , Infections à papillomavirus/diagnostic , Infections à papillomavirus/virologie , Infections à papillomavirus/génétique , Sujet âgé , Jeune adulte , Frottis vaginaux/méthodes , Valeur prédictive des tests
12.
Food Chem ; 448: 139060, 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-38537548

RÉSUMÉ

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), a type of fatty acid that has many health benefits, are of increasing concern. Herein, we developed a method for the rapid esterification and enrichment of ω-3 PUFAs in eggs, which includes microwave-assisted esterification (MAE) and electrically enhanced solid-phase microextraction (EE-SPME). Combined with gas chromatographic, efficient detection of ω-3 PUFAs was achieved in eggs. Under microwave radiation, the esterification efficiency exhibited a significant increase ranging from 5.06 to 10.65 times. The EE-SPME method reduced extraction time from 50 to 15 min. In addition, improvements in extractive fiber coating materials were explored, which ensured efficient extraction of ω-3 PUFAs. Under the optimal conditions, the method displayed a low detection limit (1.01-1.54 µg L-1), good recoveries (85.82%-106.01%), and wide linear range (7.5-1000 µg L-1), which was successfully applied to determine ω-3 PUFAs in real egg samples.

13.
J Transl Autoimmun ; 8: 100239, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38550612

RÉSUMÉ

Objectives: Antibodies to gp210 and sp100 are specific and unique anti-nuclear autoantibodies (ANAs) associated with primary biliary cholangitis (PBC). Importantly the presence of anti-gp210 and anti-sp100 responses is indicative of poor clinical outcomes. However, the utility of measuring titers of these antibodies remains unclear. Materials and methods: Using the in-house purified gp210 (HSA108-C18) and sp100 (amino acid position 296-386), we quantitatively measured serum autoantibodies to gp210 and sp100 using chemiluminescence immunoassay (CLIA) in a very large cohort of 390 patients with PBC, including 259 cases with no prior ursodesoxycholic acid (UDCA) treatment and 131 cases with UDCA treatment. We also analyzed serial changes in anti-gp210 and anti-sp100 levels in 245 sequential samples from 88 patients. Results: In our cross-sectional analysis, we detected anti-gp210 immunoglobulin G (IgG) and anti-sp100 IgG autoantibodies in 129 out of 390 (33.1%) and 80 out of 390 (20.5%) PBC patients, respectively. Multivariate analysis revealed that serum IgG (st.ß = 0.35, P = 0.003) and gamma-glutamyltransferase (GGT) (st.ß = 0.23, P = 0.042) levels at baseline were independently associated with anti-gp210 concentrations. In serial testing, we observed significant fluctuations in anti-gp210 antibody levels. These fluctuations reflected responsiveness to UDCA therapy, particularly in anti-gp210-positive patients with initially lower concentrations in the stages of disease. Conclusions: Our study reflects that quantitative changes of anti-gp210 antibody are indicative of UDCA responses. There is a great need for newer metrics in PBC and we suggest that a more detailed and longer study of these unique ANAs is warranted.

14.
MedComm (2020) ; 5(3): e505, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38469548

RÉSUMÉ

Triple-positive breast cancer (TPBC) poorly responds to current standard neoadjuvant therapy (trastuzumab plus pertuzumab and chemotherapy). Our previous MUKDEN 01 study showed a promising total pathological complete response (tpCR) rate of 30.4% with neoadjuvant pyrotinib (pan-human epidermal growth factor receptor tyrosine kinase inhibitor) plus dalpiciclib (cyclin-dependent kinase 4/6 inhibitor) and letrozole, but the efficacy remains suboptimal. This pilot study (NCT05228951) explored adding trastuzumab to this triplet neoadjuvant regimen in patients with stage II-III TPBC. The primary endpoint was tpCR (ypT0/is, ypN0) rate. Between February 2022 and June 2022, 12 patients were enrolled, and seven (58%; 95% confidence interval [CI], 27.7%-84.8%) patients achieved tpCR. The rate of residual cancer burden (RCB) 0-I was 75% (95% CI, 46.8%-91.1%). The objective response rate (ORR) was 92% (95% CI, 64.6%-98.5%). Mean Ki-67 level was significantly reduced from 45.0% (95% CI, 19.5%-70.5%) at baseline to 17.2% (95% CI, 0.7%-33.7%) after neoadjuvant therapy (p = 0.03). The most common grade 3 adverse events were diarrhea (four [33%]) and decreased neutrophil count (three [25%]). No grade 4 adverse events or treatment-related deaths occurred. This four-drug neoadjuvant regimen shows promising pathological response with an acceptable safety profile in patients with TPBC. A randomized controlled trial (NCT05638594) of this regimen is being conducted.

15.
J Transl Autoimmun ; 8: 100234, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38405661

RÉSUMÉ

The biliary epithelial cells release CC chemokine receptor 6 (CCR6) ligand 20 (CCL20), leading to recruitment of CCR6+ T cells and subsequent infiltration into the biliary epithelium in primary biliary cholangitis patients. Previous genome-wide multi-national meta-analysis, including our Han Chinese cohort, showed significant association of CCR6 and CCL20 single nucleotide polymorphisms (SNP) with PBC. We report here that significantly associated SNPs, identified in the CCR6 locus based on our Han Chinese genome-wide association study, can be separated into "protective" and "risk" groups, but only "risk" SNPs were confirmed using a separate Han Chinese PBC cohort. Only weak association of CCL20 SNPs was observed in Han Chinese PBC cohorts. Fine-mapping and logistical analysis identified a previously defined functional variant that, leads to increased CCR6 expression, which contributed to increased genetic susceptibility to PBC in Han Chinese cohort.

16.
Chem Res Toxicol ; 37(1): 57-71, 2024 01 15.
Article de Anglais | MEDLINE | ID: mdl-38177062

RÉSUMÉ

Epimedii Folium (EF) is a botanical dietary supplement to benefit immunity. Baohuoside I (BI), a prenylated flavonoid derived from EF, has exhibited the cholestatic risk before. Here, the mechanism of BI on the stability and membrane localization of liver MRP2, a bile acid exporter in the canalicular membrane of hepatocytes, was investigated. The fluorescent substrate of MRP2, CMFDA was accumulated in sandwich-cultured primary mouse hepatocytes (SCH) under BI stimulation, followed by reduced membrane MRP2 expression. BI triggered MRP2 endocytosis associated with oxidative stress via inhibition of the NRF2 signaling pathway. Meanwhile, BI promoted the degradation of MRP2 by reducing its SUMOylation and enhancing its ubiquitination level. Co-IP and fluorescence colocalization experiments all proved that MRP2 was a substrate protein for SUMOylation for SUMO proteins. CHX assays showed that SUMO1 prolonged the half-life of MRP2 and further increased its membrane expression, which could be reversed by UBC9 knockdown. Correspondingly, MRP2 accumulated in the cytoplasm by GP78 knockdown or under MG132 treatment. Additionally, the SUMOylation sites of MRP2 were predicted by the algorithm, and a conversion of lysines to arginines at positions 940 and 953 of human MRP2 caused its decreased stability and membrane location. K940 was further identified as the essential ubiquitination site for MRP2 by an in vitro ubiquitination assay. Moreover, the decreased ubiquitination of MRP2 enhanced the SUMOylation MRP2 and vice versa, and the crosstalk of these two modifiers could be disrupted by BI. Collectively, our findings indicated the process of MRP2 turnover from the membrane to cytoplasm at the post-translational level and further elucidated the novel toxicological mechanism of BI.


Sujet(s)
Protéines associées à la multirésistance aux médicaments , Sumoylation , Souris , Animaux , Humains , Protéines associées à la multirésistance aux médicaments/génétique , Protéines associées à la multirésistance aux médicaments/métabolisme , Protéine-2 associée à la multirésistance aux médicaments , Hépatocytes/métabolisme , Flavonoïdes/métabolisme , Ubiquitination
17.
Huan Jing Ke Xue ; 45(1): 335-342, 2024 Jan 08.
Article de Chinois | MEDLINE | ID: mdl-38216483

RÉSUMÉ

The composition of soil organic carbon and its stability mechanism are the key to understanding the terrestrial carbon sink capacity. The stability of soil organic carbon in a karst ecosystem greatly affects the soil carbon fixation capacity. In order to understand the impact of human activities on the stability of soil organic carbon in karst areas, the karst valley area of Zhongliang Mountain in Chongqing was selected as an example, and soil samples of four typical land use modes (mixed forest, bamboo forest, grassland, and cultivated land) were collected in layers to analyze the total organic carbon (TOC) and heavy fraction organic carbon (HFOC). The distribution characteristics of light fraction organic carbon (LFOC), labile organic carbon (LOC), and recalcitrant organic carbon (ROC) were analyzed quantitatively by using a structural equation model to provide basic data for soil carbon sink assessment and soil quality protection in karst areas. The results showed that the organic carbon components under different land use patterns in karst areas had obvious surface accumulation, and the content of organic carbon components in the surface layer was 1.2 times that in the bottom layer. Except for LFOC, the content of other organic carbon components was the highest in the mixed forest, followed by that in the bamboo forest and wasteland, with the lowest in cultivated land. Mixed forest ω(TOC) content was the highest, 42.5 g·kg-1, followed by that of bamboo forest (36.6 g·kg-1) and grassland (18.7 g·kg-1), and cultivated land content was the lowest, 13.4 g·kg-1. The soil organic carbon content of cultivated land was 68.5%, 63.5%, and 28.3% lower than that of mixed forest, bamboo forest, and grassland, respectively. Mixed forest had the highest content of ω(HFOC), 21 g·kg-1, followed by those of bamboo forest (20.9 g·kg-1), grassland (18.2 g·kg-1), and cultivated land (13.5 g·kg-1). The mixed forest ω(LOC) content was the highest, 16.3 g·kg-1, followed by those of bamboo forest (14.9 g·kg-1), grassland (11.5 g·kg-1), and cultivated land (5.3 g·kg-1). Mixed forest ω (ROC) content was the highest, 25.7 g·kg-1, followed by those of bamboo forest (21.6 g·kg-1), grassland (15.9 g·kg-1), and cultivated land (10.3 g·kg-1). The bamboo forest land ω(LFOC) content was 15.9 g·kg-1, followed by those of mixed forest (13.9 g·kg-1), grassland (7.3 g·kg-1), and cultivated land (4.9 g·kg-1). The recalcitrant organic carbon index (ROCI) was used to indicate the stability of soil organic carbon. The variation range of ROCI was 33.9%-64.5%, of which the highest was mixed forest (64.5%-66.3%), and the lowest was cultivated land (33.8%-39.6%). The ROCI of mixed forest, bamboo forest, and grassland were 1.8 times, 1.6 times, and 1.4 times that of cultivated land, respectively. Karst area ω (inert organic carbon) content and ROCI showed that human agricultural activities caused the reduction in soil organic carbon content and the destruction of soil physical structure, resulting in the accelerated decomposition and turnover rate of soil organic matter. The most important factor affecting soil stability in karst areas was soil pH. Tillage activities caused soil pH to rise, reduced soil microbial activity, and were not conducive to the accumulation of the inert organic carbon and soil organic carbon pool in the soil.

18.
Food Chem ; 438: 137984, 2024 Apr 16.
Article de Anglais | MEDLINE | ID: mdl-37979275

RÉSUMÉ

The presence of estrogens residues in dairy products is a growing concern due to their potential health risk. Herein, in this study, we have developed a membrane-protected magnetic solid-phase extraction (MP-MSPE) method that utilized a magnetic adsorbent (Fe3O4@COF-LZU1) with in-situ growth for the efficient extraction of estrone (E1), 17ß-estradiol (E2), and estriol (E3). When combined with HPLC-FLD, this method allows for the efficient detection of estrogens in dairy products. The stability of the MP-MSPE was improved by the presence of a dialysis membrane, which remained a high extraction efficiency (90 %) even after ten reuse cycles. The hydrogen bonding, π-π interactions and pore size effect contribute to the excellent adsorption of three estrogens onto Fe3O4@COF-LZU1. Under optimal conditions, the method exhibits a low detection limit (0.01-0.15 µg L-1), wide linear range (0.1-800 µg L-1), and favorable recoveries (77.3 %-109.4 %) at three concentration levels (10, 50 and 100 µg L-1). This proposed method is characterized by its simplicity, high efficiency and eco-friendliness, making it a promising approach for extracting estrogens from dairy products.


Sujet(s)
Oestrogènes , Réseaux organométalliques , Réseaux organométalliques/composition chimique , Dialyse rénale , Extraction en phase solide/méthodes , Produits laitiers , Chromatographie en phase liquide à haute performance , Phénomènes magnétiques , Limite de détection
19.
J Hosp Palliat Nurs ; 26(2): E46-E54, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-37976393

RÉSUMÉ

Truth-telling and life-sustaining treatment decisions are important elements of the quality of patients' care at the end of life. As the primary caregivers of patients at the end of life in intensive care units (ICUs), ICU nurses play an important role in patient decision making and hospice care. This study aimed to investigate and analyze ICU nurses' attitudes toward truth-telling, attitudes toward end-of-life life-sustaining treatment, and end-of-life decision-making behavioral intentions. One hundred twenty-two ICU nurses participated in this cross-sectional survey. Data were collected using a validated questionnaire. The results showed that ICU nurses' attitudes toward telling patients the truth and end-of-life life-sustaining treatment were both positive, but further improvement is needed. Nurses have a higher willingness to make palliative care decisions for patients at the end of life and to help patients achieve a good death. The truth-telling attitude, the life-sustaining treatment attitude, and whether they knew that cardiopulmonary resuscitation could be legally forgone at the end of life were factors influencing ICU nurses' behavioral intention toward decision making for patients at the end of life (all P s < .05). We conclude that nurses' participation in truth-telling and end-of-life decision making should be promoted, and timely hospice care should be provided to patients to help them achieve a good death.


Sujet(s)
Intention , Infirmières et infirmiers , Humains , Études transversales , Unités de soins intensifs , Mort
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE