Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 573
Filtrar
1.
J Asian Nat Prod Res ; : 1-10, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39066681

RESUMO

Five undescribed compounds, including a triterpenoid (1), three phenylpropanoids [(±)-2 and 4], and an aromatic compound (3), as well as six known analogues (5-10), were isolated from the resins of Liquidambar orientalis Mill. Their structures, including absolute configurations, were determined by using spectroscopic and computational methods, and the five new compounds displayed anti-inflammatory activities in LPS-induced RAW264.7 cells.

3.
Phytochemistry ; : 114226, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39047853

RESUMO

Ganoderma lucidum, a medicinal mushroom with a long history in traditional Chinese medicine, is widely used for chronic diseases. Ganospirones A-G (1-7), seven pairs of undescribed spiro-meroterpenoids, were isolated from the fruiting bodies of G. lucidum. Their structures including absolute configurations were characterized by using NMR spectroscopic data, ECD computational and X-ray diffraction methods. The anti-inflammatory and anti-renal fibrosis activities of the meroterpenoids 1-7 were tested, and the results revealed that (-)-2 and (+)-2 could inhibit iNOS expression in lipopolysaccharide-induced RAW264.7 cells at 20 µM.

4.
Scand J Gastroenterol ; : 1-8, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054602

RESUMO

AIM: To evaluate the effect of sodium picosulfate/magnesium citrate (SPMC) and 3 L split-dose polyethylene glycol (PEG) with or without dimethicone on bowel preparation before colonoscopy. METHODS: In this multicenter, prospective, randomized, controlled study conducted from April 2021 to December 2021, consecutive adult patients scheduled for colonoscopy were prospectively randomized into four groups: SPMC, SPMC plus dimethicone, 3 L PEG, and 3 L PEG plus dimethicone. Primary endpoint was colon cleansing based on Boston Bowel Preparation Scale (BBPS). Secondary endpoints were bubble score, time to cecal intubation, adenoma detection rate (ADR), patient safety and compliance, and adverse events. RESULTS: We enrolled 223 and 291 patients in SPMC and 3 L PEG group, respectively. The proportion with acceptable bowel cleansing, total BBPS score and cecal intubation time were similar in all four subgroups (p > 0.05). Patient-reported acceptability and tolerability was significantly greater in SPMC than 3 L PEG group (p < 0.001); adverse events were significantly lower in SPMC than latter group (p < 0.001). ADR in both groups was greater than 30%. CONCLUSION: SPMC had significantly higher acceptability and tolerability than 3 L PEG, however, was similar in terms of bowel-cleansing effect and cecal intubation time and hence can be used before colonoscopy preparation.

5.
Nature ; 631(8021): 654-662, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987590

RESUMO

Large-scale cell death is commonly observed during organismal development and in human pathologies1-5. These cell death events extend over great distances to eliminate large populations of cells, raising the question of how cell death can be coordinated in space and time. One mechanism that enables long-range signal transmission is trigger waves6, but how this mechanism might be used for death events in cell populations remains unclear. Here we demonstrate that ferroptosis, an iron- and lipid-peroxidation-dependent form of cell death, can propagate across human cells over long distances (≥5 mm) at constant speeds (around 5.5 µm min-1) through trigger waves of reactive oxygen species (ROS). Chemical and genetic perturbations indicate a primary role of ROS feedback loops (Fenton reaction, NADPH oxidase signalling and glutathione synthesis) in controlling the progression of ferroptotic trigger waves. We show that introducing ferroptotic stress through suppression of cystine uptake activates these ROS feedback loops, converting cellular redox systems from being monostable to being bistable and thereby priming cell populations to become bistable media over which ROS propagate. Furthermore, we demonstrate that ferroptosis and its propagation accompany the massive, yet spatially restricted, cell death events during muscle remodelling of the embryonic avian limb, substantiating its use as a tissue-sculpting strategy during embryogenesis. Our findings highlight the role of ferroptosis in coordinating global cell death events, providing a paradigm for investigating large-scale cell death in embryonic development and human pathologies.


Assuntos
Retroalimentação Fisiológica , Ferroptose , Espécies Reativas de Oxigênio , Animais , Embrião de Galinha , Humanos , Cistina/metabolismo , Retroalimentação Fisiológica/fisiologia , Ferroptose/fisiologia , Glutationa/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos , NADPH Oxidases/metabolismo , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Desenvolvimento Embrionário , Extremidades/embriologia
6.
Phytochemistry ; 225: 114173, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38851474

RESUMO

Saponins are bioactive components of many medicinal plants, possessing complicated chemical structures and extensive pharmacological activities, but the production of high-value saponins remains challenging. In this study, a 6'-O-glucosyltransferase PpUGT7 (PpUGT91AH7) was functionally characterized from Paris polyphylla Smith var. yunnanensis (Franch.) Hand. -Mazz., which can transfer a glucosyl group to the C-6' position of diosgenin-3-O-rhamnosyl-(1 â†’ 2)-glucoside (1), pennogenin-3-O-rhamnosyl-(1 â†’ 2)-glucoside (2), and diosgenin-3-O-glucoside (5). The KM and Kcat values of PpUGT7 towards the substrate 2 were 8.4 µM and 2 × 10-3 s-1, respectively. Through molecular docking and site-directed mutagenesis, eight residues were identified to interact with the sugar acceptor 2 and be crucial for enzyme activity. Moreover, four rare ophiopogonins and ginsenosides were obtained by combinatorial biosynthesis, including an undescribed compound ruscogenin-3-O-glucosyl-(1 â†’ 6)-glucoside (10). Firstly, two monoglycosides 9 and 11 were generated using a known sterol 3-O-ß-glucosyltransferase PpUGT80A40 with ruscogenin (7) and 20(S)-protopanaxadiol (8) as substrates, which were further glycosylated to the corresponding diglycosides 10 and 12 under the catalysis of PpUGT7. In addition, compounds 7-11 were found to show inhibitory effects on the secretion of TNF-α and IL-6 in macrophages RAW264.7. The findings provide valuable insights into the enzymatic glycosylation processes in the biosynthesis of bioactive saponins in P. polyphylla var. yunnanensis, and also serve as a reference for utilizing UDP-glycosyltransferases to construct high-value or rare saponins for development of new therapeutic agents.


Assuntos
Ginsenosídeos , Glicosiltransferases , Saponinas , Glicosiltransferases/metabolismo , Glicosiltransferases/química , Saponinas/química , Saponinas/biossíntese , Saponinas/metabolismo , Ginsenosídeos/química , Ginsenosídeos/biossíntese , Ginsenosídeos/metabolismo , Animais , Camundongos , Estrutura Molecular , Células RAW 264.7 , Melanthiaceae/química , Melanthiaceae/enzimologia , Melanthiaceae/metabolismo , Simulação de Acoplamento Molecular , Liliaceae/química
7.
Phytochemistry ; 225: 114185, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38876164

RESUMO

Five undescribed leucosesterterpane sesterterpenoids, leucosceptrines A-E, two undescribed penta-nor-leucosesterterpane (C20) sesterterpenoids, nor-leucosceptrines A and B, and three known analogues, were obtained from the aerial parts of Leucosceptrum canum of Chinese origin. Leucosceptrines A-C are the first examples of leucosesterterpane-type sesterterpenoids with unclosed dihydropyran rings and reverse configurations at chiral centers C-4 and/or C-12. Nor-leucosceptrines A and B possesses an unusual penta-nor-leucosesterterpane skeleton. Their structures were unambiguously elucidated through comprehensive spectroscopic analyses and single-crystal X-ray diffraction. A plausible biogenetic pathway for these sesterterpenoids was proposed. The immunosuppressive effects of these isolates on the secretion of the cytokine IFN-γ by T cells stimulated with anti-CD3/CD28 monoclonal antibodies were observed with different potencies.


Assuntos
Imunossupressores , Sesterterpenos , Sesterterpenos/química , Sesterterpenos/farmacologia , Sesterterpenos/isolamento & purificação , Imunossupressores/farmacologia , Imunossupressores/química , Imunossupressores/isolamento & purificação , Estrutura Molecular , Humanos , Linfócitos T/efeitos dos fármacos , Relação Estrutura-Atividade , Conformação Molecular , Interferon gama
8.
Phytochemistry ; 225: 114188, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38878943

RESUMO

Phytochemical investigation on the fruits of Cydonia oblonga Mill., a traditional Uighur medicine, led to the isolation of seven undescribed and nine known megastigmane glycosides. Their structures including absolute configurations were characterized by an extensive analysis of spectroscopic data including HRESIMS and NMR, combined with ECD calculations. Additionally, compounds 1, 2, 4, and 6-16 exhibited anti-inflammatory activity by inhibiting the secretion of cytokines TNF-α and IL-6 in RAW264.7 cells induced by lipopolysaccharides (LPS) with inhibitory rates of 10.79%-44.58% at 20 µM.


Assuntos
Cicloexanonas , Glicosídeos , Lipopolissacarídeos , Norisoprenoides , Norisoprenoides/química , Norisoprenoides/farmacologia , Norisoprenoides/isolamento & purificação , Camundongos , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Células RAW 264.7 , Animais , Cicloexanonas/química , Cicloexanonas/farmacologia , Cicloexanonas/isolamento & purificação , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Estrutura Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Relação Estrutura-Atividade , Relação Dose-Resposta a Droga , Glucosídeos
9.
Eur Radiol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750169

RESUMO

OBJECTIVES: To evaluate signal enhancement ratio (SER) for tissue characterization and prognosis stratification in pancreatic adenocarcinoma (PDAC), with quantitative histopathological analysis (QHA) as the reference standard. METHODS: This retrospective study included 277 PDAC patients who underwent multi-phase contrast-enhanced (CE) MRI and whole-slide imaging (WSI) from three centers (2015-2021). SER is defined as (SIlt - SIpre)/(SIea - SIpre), where SIpre, SIea, and SIlt represent the signal intensity of the tumor in pre-contrast, early-, and late post-contrast images, respectively. Deep-learning algorithms were implemented to quantify the stroma, epithelium, and lumen of PDAC on WSIs. Correlation, regression, and Bland-Altman analyses were utilized to investigate the associations between SER and QHA. The prognostic significance of SER on overall survival (OS) was evaluated using Cox regression analysis and Kaplan-Meier curves. RESULTS: The internal dataset comprised 159 patients, which was further divided into training, validation, and internal test datasets (n = 60, 41, and 58, respectively). Sixty-five and 53 patients were included in two external test datasets. Excluding lumen, SER demonstrated significant correlations with stroma (r = 0.29-0.74, all p < 0.001) and epithelium (r = -0.23 to -0.71, all p < 0.001) across a wide post-injection time window (range, 25-300 s). Bland-Altman analysis revealed a small bias between SER and QHA for quantifying stroma/epithelium in individual training, validation (all within ± 2%), and three test datasets (all within ± 4%). Moreover, SER-predicted low stromal proportion was independently associated with worse OS (HR = 1.84 (1.17-2.91), p = 0.009) in training and validation datasets, which remained significant across three combined test datasets (HR = 1.73 (1.25-2.41), p = 0.001). CONCLUSION: SER of multi-phase CE-MRI allows for tissue characterization and prognosis stratification in PDAC. CLINICAL RELEVANCE STATEMENT: The signal enhancement ratio of multi-phase CE-MRI can serve as a novel imaging biomarker for characterizing tissue composition and holds the potential for improving patient stratification and therapy in PDAC. KEY POINTS: Imaging biomarkers are needed to better characterize tumor tissue in pancreatic adenocarcinoma. Signal enhancement ratio (SER)-predicted stromal/epithelial proportion showed good agreement with histopathology measurements across three distinct centers. Signal enhancement ratio (SER)-predicted stromal proportion was demonstrated to be an independent prognostic factor for OS in PDAC.

10.
Biomed Pharmacother ; 175: 116784, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38781865

RESUMO

1,8-Cineole is a bicyclic monoterpene widely distributed in the essential oils of various medicinal plants, and it exhibits significant anti-inflammatory and antioxidant activities. We aimed to investigate the therapeutic effect of 1,8-cineole on anti-Alzheimer's disease by using transgenic Caenorhabditis elegans models. Our studies demonstrated that 1,8-cineole significantly relieved Aß1-42-induced paralysis and exhibited remarkable antioxidant and anti-Aß1-42 aggregation activities in transgenic nematodes CL4176, CL2006 and CL2355. We developed a 1,8-cineole/cyclodextrin inclusion complex, displaying enhanced anti-paralysis, anti-Aß aggregation and antioxidant activities compared to 1,8-cineole. In addition, we found 1,8-cineole treatment activated the SKN-1/Nrf-2 pathway and induced autophagy in nematodes. Our results demonstrated the antioxidant and anti-Alzheimer's disease activities of 1,8-cineole, which provide a potential therapeutic approach for Alzheimer's disease.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Animais Geneticamente Modificados , Antioxidantes , Caenorhabditis elegans , Eucaliptol , Eucaliptol/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Caenorhabditis elegans/efeitos dos fármacos , Antioxidantes/farmacologia , Peptídeos beta-Amiloides/metabolismo , Ciclodextrinas/farmacologia , Ciclodextrinas/química , Fragmentos de Peptídeos/farmacologia , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças
12.
J Nat Prod ; 87(4): 1103-1115, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38600744

RESUMO

Twelve new alkaloids, scolopenolines A-L (1-7, 9-11, 13, 14), along with six known analogues, were isolated from Scolopendra subspinipes mutilans, identified by analysis of spectroscopic data and quantum chemical and computational methods. Scolopenoline A (1), a unique guanidyl-containing C14 quinoline alkaloid, features a 6/6/5 ring backbone. Scolopenoline B (2) is a novel sulfonyl-containing heterodimer comprising quinoline and tyramine moieties. Scolopenoline G (7) presents a rare C12 quinoline skeleton with a 6/6/5 ring system. Alkaloids 1, 8, 10, and 15-18 display anti-inflammatory activity, while 10 and 16-18 also exhibit anti-renal-fibrosis activity. Drug affinity responsive target stability and RNA-interference assays show that Lamp2 might be a potentially important target protein of 16 for anti-renal-fibrosis activity.


Assuntos
Alcaloides , Animais Peçonhentos , Quilópodes , Animais , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Estrutura Molecular , Artrópodes/química , Fibrose/tratamento farmacológico , Rim/efeitos dos fármacos , Quinolinas/farmacologia , Quinolinas/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Humanos
13.
Orthop Surg ; 16(6): 1418-1433, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38658320

RESUMO

OBJECTIVE: Bone marrow mesenchymal stem cells (BMSCs) show significant potential for osteogenic differentiation. However, the underlying mechanisms of osteogenic capability in osteoporosis-derived BMSCs (OP-BMSCs) remain unclear. This study aims to explore the impact of YTHDF3 (YTH N6-methyladenosine RNA binding protein 3) on the osteogenic traits of OP-BMSCs and identify potential therapeutic targets to boost their bone formation ability. METHODS: We examined microarray datasets (GSE35956 and GSE35958) from the Gene Expression Omnibus (GEO) to identify potential m6A regulators in osteoporosis (OP). Employing differential, protein interaction, and machine learning analyses, we pinpointed critical hub genes linked to OP. We further probed the relationship between these genes and OP using single-cell analysis, immune infiltration assessment, and Mendelian randomization. Our in vivo and in vitro experiments validated the expression and functionality of the key hub gene. RESULTS: Differential analysis revealed seven key hub genes related to OP, with YTHDF3 as a central player, supported by protein interaction analysis and machine learning methodologies. Subsequent single-cell, immune infiltration, and Mendelian randomization studies consistently validated YTHDF3's significant link to osteoporosis. YTHDF3 levels are significantly reduced in femoral head tissue from postmenopausal osteoporosis (PMOP) patients and femoral bone tissue from PMOP mice. Additionally, silencing YTHDF3 in OP-BMSCs substantially impedes their proliferation and differentiation. CONCLUSION: YTHDF3 may be implicated in the pathogenesis of OP by regulating the proliferation and osteogenic differentiation of OP-BMSCs.


Assuntos
Biologia Computacional , Células-Tronco Mesenquimais , Osteogênese , Osteoporose Pós-Menopausa , Humanos , Osteoporose Pós-Menopausa/genética , Animais , Feminino , Células-Tronco Mesenquimais/metabolismo , Camundongos , Biologia Computacional/métodos , Osteogênese/fisiologia , Osteogênese/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Aprendizado de Máquina , Diferenciação Celular , Adenosina/metabolismo , Adenosina/genética , Adenosina/análogos & derivados
14.
J Agric Food Chem ; 72(17): 9746-9754, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602331

RESUMO

The latex of Euphorbia peplus and its major component 20-deoxyingenol-3-angelate (DI3A) displayed significant nematicidal activity against Caenorhabditis elegans and Panagrellus redivivus. DI3A treatment inhibited the growth and development of nematodes and caused significantly negative effects on locomotion behavior, reproduction, and accumulation of reactive oxygen species. Transcriptome analysis indicated that differential expression genes in DI3A-treated C. elegans were mainly associated with the metabolism, growth, and development process, which were further confirmed by RT-qPCR experiments. The expression level of TPA-1 gene encoding a protein kinase C isotype was obviously upregulated by DI3A treatment, and knockdown of TPA-1 by RNAi technology in the nematode could relieve the growth-inhibitory effect of DI3A. Metabolic analysis indicated that DI3A was hardly metabolized by C. elegans, but a glycosylated indole derivative was specifically accumulated likely due to the activation of detoxification. Overall, our findings suggested that DI3A from E. peplus latex exerted a potent nematicidal effect through the gene TPA-1, which provides a potential target for the control of nematodes and also suggests the potential application value of E. peplus latex and DI3A as botanical nematicides.


Assuntos
Antinematódeos , Caenorhabditis elegans , Euphorbia , Látex , Proteína Quinase C , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/crescimento & desenvolvimento , Látex/química , Látex/metabolismo , Antinematódeos/farmacologia , Antinematódeos/química , Antinematódeos/metabolismo , Euphorbia/química , Proteína Quinase C/metabolismo , Proteína Quinase C/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/química
15.
Org Biomol Chem ; 22(15): 3019-3024, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38530279

RESUMO

An unusual pyridine-containing sesterterpenoid, leucosceptrodine (1), and five new nor-leucosceptrane sesterterpenoids, including bisnor- (C23, 2), tetranor- (C21, 3) and pentanor- (C20, 4-6) skeletons, were isolated from the leaves of Tibetan Leucosceptrum canum. Their structures including their absolute configurations were determined by extensive spectroscopic analyses and quantum chemical calculations. A single crystal of one epimer (5) was crystallized from a pair of inseparable epimers, and its structure including its absolute configuration was determined by X-ray crystallographic analysis. The immunosuppressive activities of compounds 1-4 with different potencies were evaluated by inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.


Assuntos
Lamiaceae , Sesterterpenos , Sesterterpenos/química , Tibet , Lamiaceae/química , Cristalografia por Raios X , Piridinas/farmacologia , Estrutura Molecular
16.
Med ; 5(6): 570-582.e4, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38554711

RESUMO

BACKGROUND: Noninvasive and early assessment of liver fibrosis is of great significance and is challenging. We aimed to evaluate the predictive performance and cost-effectiveness of the LiverRisk score for liver fibrosis and liver-related and diabetes-related mortality in the general population. METHODS: The general population from the NHANES 2017-March 2020, NHANES 1999-2018, and UK Biobank 2006-2010 were included in the cross-sectional cohort (n = 3,770), along with the NHANES follow-up cohort (n = 25,317) and the UK Biobank follow-up cohort (n = 17,259). The cost-effectiveness analysis was performed using TreeAge Pro software. Liver stiffness measurements ≥10 kPa were defined as compensated advanced chronic liver disease (cACLD). FINDINGS: Compared to conventional scores, the LiverRisk score had significantly better accuracy and calibration in predicting liver fibrosis, with an area under the receiver operating characteristic curve (AUC) of 0.76 (0.72-0.79) for cACLD. According to the updated thresholds of LiverRisk score (6 and 10), we reclassified the population into three groups: low, medium, and high risk. The AUCs of LiverRisk score for predicting liver-related and diabetes-related mortality at 5, 10, and 15 years were all above 0.8, with better performance than the Fibrosis-4 score. Furthermore, compared to the low-risk group, the medium-risk and high-risk groups in the two follow-up cohorts had a significantly higher risk of liver-related and diabetes-related mortality. Finally, the cost-effectiveness analysis showed that the incremental cost-effectiveness ratio for LiverRisk score compared to FIB-4 was USD $18,170 per additional quality-adjusted life-year (QALY) gained, below the willingness-to-pay threshold of $50,000/QALY. CONCLUSIONS: The LiverRisk score is an accurate, cost-effective tool to predict liver fibrosis and liver-related and diabetes-related mortality in the general population. FUNDING: The National Natural Science Foundation of China (nos. 82330060, 92059202, and 92359304); the Key Research and Development Program of Jiangsu Province (BE2023767a); the Fundamental Research Fund of Southeast University (3290002303A2); Changjiang Scholars Talent Cultivation Project of Zhongda Hospital of Southeast University (2023YJXYYRCPY03); and the Research Personnel Cultivation Program of Zhongda Hospital Southeast University (CZXM-GSP-RC125).


Assuntos
Análise Custo-Benefício , Cirrose Hepática , Humanos , Cirrose Hepática/mortalidade , Cirrose Hepática/economia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Estudos Transversais , Diabetes Mellitus/mortalidade , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/economia , Idoso , Medição de Risco , Técnicas de Imagem por Elasticidade/economia , Valor Preditivo dos Testes , Inquéritos Nutricionais , Curva ROC
17.
J Org Chem ; 89(5): 3652-3656, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38353480

RESUMO

An efficient synthetic approach was developed and applied to the syntheses of four linear biosynthetic C25-precursors of leucosceptroids. The synthesis features a Julia-Kocienski olefination and a late-stage bioinspired photo-oxidation as key steps. The immunosuppressive effects of all synthetic compounds on mouse T cells and macrophage RAW264.7 were determined.


Assuntos
Estrutura Molecular , Animais , Camundongos , Oxirredução
18.
Cell Signal ; 115: 111038, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38195035

RESUMO

N6-methyladenosine (m6A), the most prevalent internal modification in mRNA, is related to the pathogenesis of osteoporosis (OP). Although methyltransferase Like-3 (METTL3), an m6A transferase, has been shown to mitigate OP progression, the mechanisms of METTL3-mediated m6A modification in osteoblast function remain unclear. Here, fluid shear stress (FSS) induced osteoblast proliferation and differentiation, resulting in elevated levels of METTL3 expression and m6A modification. Through Methylated RNA Immunoprecipitation Sequencing (MeRIP-seq) and Transcriptomic RNA Sequencing (RNA-seq), SRY (Sex Determining Region Y)-box 4 (SOX4) was screened as a target of METTL3, whose m6A-modified coding sequence (CDS) regions exhibited binding affinity towards METTL3. Further functional experiments demonstrated that knockdown of METTL3 and SOX4 hampered osteogenesis, and METTL3 knockdown compromised SOX4 mRNA stability. Via RNA immunoprecipitation (RIP) assays, we further confirmed the direct interaction between METTL3 and SOX4. YTH N6-Methyladenosine RNA Binding Protein 3 (YTHDF3) was identified as the m6A reader responsible for modulating SOX4 mRNA and protein levels by affecting its degradation. Furthermore, in vivo experiments demonstrated that bone loss in an ovariectomized (OVX) mouse model was reversed through the overexpression of SOX4 mediated by adeno-associated virus serotype 2 (AAV2). In conclusion, our research demonstrates that METTL3-mediated m6A modification of SOX4 plays a crucial role in regulating osteoblast proliferation and differentiation through its recognition by YTHDF3. Our research confirms METTL3-m6A-SOX4-YTHDF3 as an essential axis and potential mechanism in OP.


Assuntos
Metiltransferases , Osteoblastos , Animais , Camundongos , Proliferação de Células , Metiltransferases/metabolismo , Osteoblastos/metabolismo , RNA , RNA Mensageiro/metabolismo
19.
Phytochem Anal ; 35(4): 621-633, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38191170

RESUMO

INTRODUCTION: Steroidal saponins characterised by intricate chemical structures are the main active components of a well-known traditional Chinese medicine (TCM) Rhizoma Paridis. The metabolic profiles of steroidal saponins in vivo remain largely unexplored, despite their renowned antitumor, immunostimulating, and haemostatic activity. OBJECTIVE: To perform a comprehensive analysis of the chemical constituents of Rhizoma Paridis total saponins (RPTS) and their metabolites in rats after oral administration. METHOD: The chemical constituents of RPTS and their metabolites were analysed using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS/MS). RESULTS: A reliable UPLC-Q-TOF-MS/MS method was established, and a total of 142 compounds were identified in RPTS. Specifically, diosgenin-type saponins showed the diagnostic ions at m/z 415.32, 397.31, 283.25, 271.21, and 253.20, whereas pennogenin-type saponins exhibited the diagnostic ions at m/z 413.31, 395.30, and 251.20. Based on the characteristic fragments and standard substances, 15 specific metabolites were further identified in the faeces, urine, plasma, and bile of rats. The metabolic pathways of RPTS, including phase I reactions (de-glycosylation and oxidation) and phase II reactions (glucuronidation), were explored and summarised, and the enrichment of metabolites was characterised by multivariate statistical analysis. CONCLUSION: The intricate RPTS could be transformed into relatively simple metabolites in rats through de-glycosylation, which provides a reference for further metabolic studies and screening of active ingredients for TCM.


Assuntos
Ratos Sprague-Dawley , Saponinas , Espectrometria de Massas em Tandem , Animais , Saponinas/análise , Saponinas/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Masculino , Ratos , Rizoma/química , Medicamentos de Ervas Chinesas/química , Esteroides/análise
20.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(1): 62-66, 2024 Jan 15.
Artigo em Chinês | MEDLINE | ID: mdl-38269461

RESUMO

OBJECTIVES: To investigate the risk factors for diabetic ketoacidosis (DKA) in children/adolescents with type 1 diabetes mellitus (T1DM) and to establish a model for predicting the risk of DKA. METHODS: A retrospective analysis was performed on 217 children/adolescents with T1DM who were admitted to General Hospital of Ningxia Medical University from January 2018 to December 2021. Among the 217 children/adolescents,169 cases with DKA were included as the DKA group and 48 cases without DKA were included as the non-DKA group. The risk factors for DKA in the children/adolescents with T1DM were analyzed, and a nomogram model was established for predicting the risk of DKA in children/adolescents with T1DM. RESULTS: For the 217 children/adolescents with T1DM, the incidence rate of DKA was 77.9% (169/217). The multivariate logistic regression analysis showed that high levels of random blood glucose, hemoglobin A1c (HbA1c), blood ketone body, and triglyceride on admission were closely associated with the development of DKA in the children/adolescents with T1DM (OR=1.156, 3.2031015, 20.131, and 9.519 respectively; P<0.05). The nomogram prediction model had a C-statistic of 0.95, with a mean absolute error of 0.004 between the risk of DKA predicted by the nomogram model and the actual risk of DKA, indicating that the model had a good overall prediction ability. CONCLUSIONS: High levels of random blood glucose, HbA1c, blood ketone body, and triglyceride on admission are closely associated with the development of DKA in children/adolescents with T1DM, and targeted intervention measures should be developed to reduce the risk of DKA.


Assuntos
Diabetes Mellitus Tipo 1 , Cetose , Criança , Adolescente , Humanos , Diabetes Mellitus Tipo 1/complicações , Glicemia , Hemoglobinas Glicadas , Estudos Retrospectivos , Fatores de Risco , Corpos Cetônicos , Triglicerídeos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...