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1.
Eur Radiol Exp ; 8(1): 41, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584248

RESUMO

BACKGROUND: We investigated the value of three-dimensional amide proton transfer-weighted imaging (3D-APTWI) in the diagnosis of early-stage breast cancer (BC) and its correlation with the immunohistochemical characteristics of malignant lesions. METHODS: Seventy-eight women underwent APTWI and dynamic contrast-enhanced (DCE)-MRI. Pathological results were categorized as either benign (n = 43) or malignant (n = 37) lesions. The parameters of APTWI and DCE-MRI were compared between the benign and malignant groups. The diagnostic value of 3D-APTWI was evaluated using the area under the receiver operating characteristic curve (ROC-AUC) to establish a diagnostic threshold. Pearson's correlation was used to analyze the correlation between the magnetization transfer asymmetry (MTRasym) and immunohistochemical characteristics. RESULTS: The MTRasym and time-to-peak of malignancies were significantly lower than those of benign lesions (all p < 0.010). The volume transfer constant, rate constant, and wash-in and wash-out rates of malignancies were all significantly greater than those of benign lesions (all p < 0.010). ROC-AUCs of 3D-APTWI, DCE-MRI, and 3D-APTWI+DCE to differential diagnosis between early-stage BC and benign lesions were 0.816, 0.745, and 0.858, respectively. Only the difference between AUCAPT+DCE and AUCDCE was significant (p < 0.010). When a threshold of MTRasym for malignancy for 2.42%, the sensitivity and specificity of 3D-APTWI for BC diagnosis were 86.5% and 67.6%, respectively; MTRasym was modestly positively correlated with pathological grade (r = 0.476, p = 0.003) and Ki-67 (r = 0.419, p = 0.020). CONCLUSIONS: 3D-APTWI may be used as a supplementary method for patients with contraindications of DCE-MRI. MTRasym can imply the proliferation activities of early-stage BC. RELEVANCE STATEMENT: 3D-APTWI can be an alternative diagnostic method for patients with early-stage BC who are not suitable for contrast injection. KEY POINTS: • 3D-APTWI reflects the changes in the microenvironment of early-stage breast cancer. • Combined 3D-APTWI is superior to DCE-MRI alone for early-stage breast cancer diagnosis. • 3D-APTWI improves the diagnostic accuracy of early-stage breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Prótons , Amidas , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Microambiente Tumoral
2.
Matrix Biol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38518923

RESUMO

As the backbone of the extracellular matrix (ECM) and the perineuronal nets, Hyaluronic acid (HA) provides binding sites for proteoglycans and other ECM components. Although the pivotal of HA has been recognized in Alzheimer's disease (AD), few studies have addressed the relationship between AD pathology and HA synthases (HASs). Here, HASs in different regions of AD brains were screened in transcriptomic databases and validated in AßPP/PS1 mice. We found that HAS1 was distributed along the axon and nucleus. Its transcripts were reduced in AD patients and AßPP/PS1 mice. Phosphorylated tau (p-tau) mediates AßPP-induced cytosolic-nuclear translocation of HAS1, and negatively regulated the stability, monoubiquitination, and oligomerization of HAS1, thus reduced the synthesis and release of HA. Furthermore, non-ubiquitinated HAS1 mutant lost its enzyme activity, and translocated from the cytosol into the nucleus, forming nuclear speckles (NS). Unlike the Splicing-related NS, less than 1% of the non-ubiquitinated HAS1 co-localized with SRRM2, proving the regulatory role of HAS1 in gene transcription, indirectly. Thus, differentially expressed genes (DEGs) related to both non-ubiquitinated HAS1 mutant and AD were screened using transcriptomic datasets. Thirty-nine DEGs were identified, with 64.1% (25/39) showing consistent results in both datasets. Together, we unearthed an important function of the AßPP-p-tau-HAS1 axis in microenvironment remodeling and gene transcription during AD progression, involving the ubiquitin-proteasome, lysosome, and NS systems.

3.
PeerJ ; 11: e15587, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361035

RESUMO

Potassium plays a significant role in the basic functions of plant growth and development. Potassium uptake is closely associated with morphological characteristics of the roots. However, the dynamic characteristics of phenotype and lifespan of cotton (Gossypium hirsutum L.) lateral roots and root hairs under low and high potassium stress remain unclear. In this study, potassium stress experiments (low and high potassium, medium potassium as control) were conducted using RhizoPot (an in situ root observation device) to determine the response characteristics of lateral roots and root hairs in cotton under potassium stress. The plant morphology, photosynthetic characteristics, root phenotypic changes, and lifespan of lateral roots and root hairs were measured. Potassium accumulation, aboveground phenotype, photosynthetic capacity, root length density, root dry weight, root diameter, lateral root lifespan, and root hair lifespan under low potassium stress were significantly decreased compared to medium potassium treatment. However, the root hair length of the former was significantly increased than that of the latter. Potassium accumulation and the lateral root lifespan were significantly increased under high potassium treatment, while root length density, root dry weight, root diameter, root hair length, and root hair lifespan were significantly decreased compared to the medium potassium treatment. Notably, there were no significant differences in aboveground morphology and photosynthetic characters. Principal component analysis revealed that lateral root lifespan, root hair lifespan of the first lateral root, and root hair length significantly correlated with potassium accumulation. The root had similar regularity responses to low and high potassium stress except for lifespan and root hair length. The findings of this study enhance the understanding of the phenotype and lifespan of cotton's lateral roots and root hairs under low and high potassium stress.


Assuntos
Gossypium , Potássio , Raízes de Plantas/genética , Fenótipo , Transporte de Íons
4.
iScience ; 26(4): 106517, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37123236

RESUMO

Epithelial-to-mesenchymal transition (EMT) is the underlying mechanism for tumor metastasis and shows the metastatic potential of tumor cells. Although the transcriptional regulation of EMT has been well studied, the role of alternative splicing (AS) regulation in EMT remains largely uncharacterized. The rapid accumulation of RNA-seq datasets has provided the opportunities for developing computational methods to associate mRNA isoform variations with EMT. In this study, we propose regularization models to identify significant AS events during EMT. Our experimental results confirm that the predicted AS events are closely related to apoptosis, focal adhesion-invadopodium shift and tight junction formation that are essential during EMT. Therefore, our study highlights the broad role of posttranscriptional regulation during EMT and identifies key subsets of AS events serving as distinct regulatory nodes.

5.
Phytochemistry ; 211: 113700, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37119920

RESUMO

Plumula Nelumbinis, the embryo of the seed of Nelumbo nucifera Gaertn, is commonly used to make tea and nutritional supplements in East Asian countries. A bioassay-guided isolation of Plumula Nelumbinis afforded six previously undescribed bisbenzylisoquinoline alkaloids, as well as seven known alkaloids. Their structures were elucidated by extensive analysis of HRESIMS, NMR, and CD data. Pycnarrhine, neferine-2α,2'ß-N,N-dioxides, neferine, linsinine, isolinsinine, and nelumboferine, at 2 µM significantly suppressed the migration of MOVAS cells with inhibition ratio above 50%, more active than that of the positive control cinnamaldehyde (inhibition ratio 26.9 ± 4.92%). Additionally, neferine, linsinine, isolinsinine, and nelumboferine, were also active against the proliferation of MOVAS cells with inhibition ratio greater than 45%. The preliminary structure-activity relationships were discussed. Mechanism studies revealed that nelumboferine inhibited the migration and proliferation of MOVAS cells by regulating ORAI2/Akt signaling pathway.


Assuntos
Alcaloides , Benzilisoquinolinas , Proteínas Proto-Oncogênicas c-akt , Músculo Liso Vascular/química , Alcaloides/química , Benzilisoquinolinas/farmacologia , Proliferação de Células
6.
Front Cardiovasc Med ; 10: 1085737, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063950

RESUMO

Purpose: To confirm the ability of native T1 and T2 values in detecting and monitoring early myocardial injuries of chest radiotherapy in neoplasm patients. Materials and methods: Fifteen participants received non-anthracycline chemotherapy and chest radiotherapy, and 30 age/gender-matched controls were enrolled in this prospective study. Cardiac magnetic resonance scans were performed within 2 days, 3 months, and 6 months after chest radiotherapy. Myocardial native T1 and T2 values were measured in irradiated and nonirradiated areas. Meanwhile, the parameters of left ventricular function and left ventricular myocardial strain were obtained. Results: There were no significant differences in left ventricular function, native T1, T2, and strain between patients and controls before chest radiotherapy. In 15 participants who were followed up for 6 months, there was a significant change only in left ventricular ejection fraction (LVEF) among baseline and the first follow-up (P = 0.021), while the adjusted P-value was higher than 0.05 after Bonferroni correction, as well as other parameters. Native T1 values were elevated at 3 and 6 months in irradiated areas compared with baseline (1,288.72 ± 66.59 ms vs. 1,212.51 ± 45.41 ms; 1,348.01 ± 54.16 ms vs. 1,212.51 ± 45.41 ms; P < 0.001 for both). However, T2 values only changed at 3 months in irradiated areas compared with baseline (44.21 ± 3.35 ms vs. 39.14 ± 1.44 ms; P = 0.006). Neither the native T1 nor T2 values changed in nonirradiated areas during the follow-up period (all P > 0.05). There were no significant differences in strain changes during the follow-up period (all P > 0.05). Conclusion: Native T1 and T2 values elevated at 3 months after chest radiotherapy, whereas LVEF showed no significant change during the 6-month follow-up.

7.
J Nat Prod ; 86(2): 406-415, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36748235

RESUMO

22,25-Epoxylanostane triterpenoids indicated protective effects against oxygen-glucose deprivation/reoxygenation (OGD/R)-induced myocardial injury in a previous study. In order to discover potent cardioprotective agents, 20 22,25-epoxylanostane triterpenoids, including inonotsuoxides A and B, ganodercochlearins A and B, were synthesized from inotodiol (1). The structures of inonotsuoxide B and ganodercochlearin A are revised as 22R,25-epoxylanosta-8-en-3ß,24R-diol (6) and 22S,25-epoxylanosta-7,9(11)-dien-3ß,24R-diol (12) respectively, based on synthesis, spectroscopic data analysis, and X-ray crystallography. Compounds 13-16 and 22 showed potential protective activity against OGD/R-induced injury in H9c2 cells at a concentration of 20 µM. After OGD/R treatment, the most active compounds 13 and 22 at 5 µM increased cell viability by 11.4% and 6.4% respectively, whereas the positive control diazoxide was 14.9% at 100 µM. Flow cytometric analysis and JC-1 staining assay revealed that 13 suppressed OGD/R-induced apoptosis and the mitochondrial membrane potential in H9c2 cells. Compound 13 may serve as a potential lead cardioprotective agent for further development.


Assuntos
Oxigênio , Triterpenos , Apoptose , Glucose/metabolismo , Oxigênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Triterpenos/farmacologia
8.
Planta Med ; 89(2): 208-217, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36170856

RESUMO

Four new furostanol saponins (1:  - 4: ) and a new pregane-type saponin (5: ) along with six known steroidal saponins (6:  - 11: ) were isolated from the rhizomes of Smilax china. The structures of 1:  - 5: were elucidated by extensive analysis of NMR and HR-ESI-MS data in addition to enzymatic hydrolysis and other chemical methods. Compounds 1, 4: , and 11: showed inhibitory activity against the expression of proinflammatory mediators, inducible nitric oxide synthase, interleukin-1ß, interleukin-6, and tumor necrosis factor-α in lipopolysaccharide-induced RAW264.7 cells. Compound 1: , at a concentration of 20 µM, decreased the production of inducible nitric oxide synthase, interleukin-1ß, interleukin-6, and tumor necrosis factor-α by 36, 62, 72, and 67%, respectively, which is comparable to that of the positive control dexamethasone.


Assuntos
Citocinas , Saponinas , Smilax , China , Citocinas/metabolismo , Interleucina-1beta , Interleucina-6 , Lipopolissacarídeos , Óxido Nítrico Sintase Tipo II , Rizoma/química , Saponinas/química , Smilax/química , Fator de Necrose Tumoral alfa , Animais , Camundongos , Células RAW 264.7
9.
Front Endocrinol (Lausanne) ; 13: 917761, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034443

RESUMO

Objective: The aim of the study was to evaluate the effect of empagliflozin on diffuse myocardial fibrosis by cardiac magnetic resonance (CMR) T1 mapping. Research methods and procedures: Databases including PubMed, Cochrane library, Embase, and Sinomed for clinical studies of empagliflozin on myocardial fibrosis were searched. Two authors extracted the data and evaluated study quality independently. Weighted mean difference (WMD) and 95% confidence intervals (CI) were used for continuous variables. Review Manager 5.3 was used to performed the analysis. Results: Six studies were included in this meta-analysis. One of the six studies was assessed as poor quality by the assessment of methodological quality; however, the remaining five studies were considered good. The WMD value of △extracellular volume (ECV) was merged by the fixed-effect model, and the pooled effect size was -1.48 (95% CI -1.76 to -1.21, P < 0.00001), which means in favor of empagliflozin. Heterogeneity analysis did not find any heterogeneity (chi2 = 0.39, P = 0.82, I 2 = 0%). In addition, empagliflozin had a tendency to reduce ECV compared to treatment before with no statistical significance (WMD = -0.29, 95% CI -1.26 to 0.67, P = 0.55; heterozygosity test, chi2 = 2.66, P = 0.45, I 2 = 0%). The WMD value of △native T1 was also merged by the fixed-effect model, but the pooled effect size showed neither statistical difference between empagliflozin and placebo treatment (WMD = -5.40, 95% CI -21.63 to 10.83, P = 0.51) nor heterogeneity (chi2 = 0.05, P = 0.83, I 2 = 0%). Conclusions: Empagliflozin has cardiovascular benefits by reducing diffuse myocardial fibrosis. ECV could act as a non-invasive imaging tool to assess diffuse myocardial fibrosis and monitor disease progression. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=324804, identifier: CRD42022324804.


Assuntos
Cardiomiopatias , Miocárdio , Compostos Benzidrílicos , Fibrose , Glucosídeos , Humanos
10.
Front Plant Sci ; 13: 932912, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845711

RESUMO

Melatonin (N-acetyl-5-methoxytryptamine, MT) can mitigate abotic stress, including drought stress on a number of crops. However, it is unclear whether and how seed priming with melatonin alleviates the effects of drought stress on seed germination and seedling growth of triticale (Triticale hexaploide L.). In this study, we investigated the effects of seed priming with MT on seed germination, protective enzyme activity, superoxide anion, and hydrogen peroxide in triticale under PEG-6000 induced drought stress. Seed priming with 20 µM MT alleviated the adverse effects of PEG-6000 induced drought stress on seed germination and seedling growth. Triticale seeds primed with 20 µM MT exhibited improved germination potential, germination rate, germ and radicle length. Specifically, MT priming increased the germination rate by 57.67% compared with unprimed seeds. Seed priming with melatonin also alleviated the adverse effects of PEG-6000 induced drought stress on triticale seedlings. MT pretreatment with 20 µM significantly increased the net photosynthetic rate, transpiration rate, stomatal conductance, plant height, leaf area, and relative chlorophyll concentration, enhanced the activities of superoxide dismutase and peroxidase, and decreased reactive oxygen species (ROS) and malonaldehyde content in the seeds (germ and radicle) and seedlings (leaf and root). Collectively, these results suggest that seed priming with melatonin promotes ROS scavenging capacity and enhances energy supply and antioxidant enzyme activities to alleviate the adverse effects of drought stress in triticale.

11.
Int J Mol Sci ; 23(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35563437

RESUMO

Mepiquat chloride (MC) is a plant growth regulator widely used in cotton production to control vegetative overgrowth of cotton plants to achieve ideal plant architecture required for high yielding. Cotton varieties respond differently to MC application, but there is little information about the molecular mechanisms underlying the varietal difference. In this study, comparative transcriptome analysis was conducted by using two Upland cotton varieties with different sensitivity (XLZ74, insensitive; SD1068, sensitive) to MC treatment, aiming to understand the molecular mechanisms responsible for varietal difference of MC sensitivity. RNA-seq data were generated from the two varieties treated with MC or water at three time points, 1, 3 and 6 days post-spray (dps). Genes differentially expressed between the MC and mock treatments of XLZ74 (6252) and SD1068 (6163) were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to compare the enriched GO terms and KEGG pathways between the two varieties. Signal transduction of phytohormones, biosynthesis of gibberellins (GAs) and brassinosteroids (BRs) and profiles of transcription factors (TFs) seemed to be differentially affected by MC in the two varieties. The transcriptomic results were further consolidated with the content changes of phytohormones in young stem. Several GA catabolic genes, GA2ox, were highly induced by MC in both varieties especially in SD1068, consistent with a more significant decrease in GA4 in SD1068. Several AUX/IAA and SAUR genes and CKX genes were induced by MC in both varieties, but with a more profound effect observed in SD1068 that showed a significant reduction in indole-3-acetic acid (IAA) and a significant increase in cytokinin (CTK) at 6 days post-spray (dps). BR biosynthesis-related genes were downregulated in SD1068, but not in XLZ74. Additionally, more downregulated TFs were observed in MC-treated SD1068 than in MC-treated XLZ74, and the two varieties had very different profiles of genes involved in starch and sucrose metabolism, with those of SD1068 and XLZ74 being downregulated and upregulated by MC treatment, respectively. Together, these results indicate that although the same or similar biological pathways are affected by MC treatment in cotton varieties showing different MC sensitivity, the extent of effect is variable, leading to their different phenotypic outcomes. How the quantitative effect of MC on the biological processes associated with growth retardation is regulated is still an open question.


Assuntos
Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas , Perfilação da Expressão Gênica , Gossypium/genética , Gossypium/metabolismo , Piperidinas , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Transcriptoma
12.
PeerJ ; 9: e12111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34917420

RESUMO

Planting density affects crop microclimate and intra-plant competition, playing an important role on yield formation and resource use, especially in areas where the cotton is grown at relatively high plant densities in Xinjiang, China. However, more studies are needed to examine how the change in planting density affects the microclimate factors such as the fraction of light intercepted (FLI), air temperature(T) and relative humidity (RH) within different canopy layers, which in turn affect the boll number per plant (BNF), boll number per unit area (BNA), boll weight (BW), and boll-setting rate (BSR) at fruiting branch (FB) positions FB1-3, FB4-6, and FB≥7 in cotton. To quantify the relationships between boll characteristics, yield, and microclimate factors, we conducted a 2-year field experiment in 2019-2020 in Xinjiang with six plant densities: 9 (P1), 12 (P2), 15 (P3), 18 (P4), 21 (P5), and 24 (P6) plants m-2. With each three plants m-2 increase in density, the average FLI and RH across different canopy layers increased by 0.37 and 2.04%, respectively, whereas T decreased by 0.64 °C. The BNF at FB≥ 7, FB4-6, and FB1-3 decreased by 0.82, 0.33, and 0.5, respectively. The highest BNA was observed in the upper and middle layers in the P4 treatment and in the lowest canopy layer with the P5. The highest BW was measured in the middle canopy layer for P3, and the highest BSR was measured in the lower layer for P3. Plant density exhibited linear or quadratic relationships with FLI, T, and RH. Microclimate factors mainly affected the boll number in each layer, but had no significant effects on the BW in any layer or the BSR in the middle and lower layers. Cotton yield was non-linearly related to plant density. The 2-year maximum yield was achieved at a plant density of 21 plants m-2, but the yield increase compared to the yield with a density of 18 plants m-2was only 0.28%. Thus, we suggest that the optimal plant density for drip-irrigated cotton in Xinjiang is 18 plants m-2, which could help farmers grow machine-harvested cotton.

13.
Phytochemistry ; 191: 112907, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34399303

RESUMO

Seven undescribed 22-hydroxylanostane triterpenoids were isolated from the fruiting bodies of Phellinus igniarius, together with three known sterols. Their structures were assigned by extensive spectroscopic and HRESIMS data analyses. The absolute configurations of C-22 were determined by X-ray crystallography, chemical methods, and spectroscopic data comparison. Phellinol G was a 25,26,27-trinorlanostane triterpenoid glycoside. 22S/22R-25,26,27- Trinorlanosta-8-en-3ß,22,24-triols with the same side chain as that of phellinol G were stereoselectively synthesized from commercial lanosterol for the first time. The key step involved Sharpless asymmetrical epoxidation. Phellinols A, B, and F showed cardioprotective activity against oxygen-glucose deprivation/reoxygenation injury in H9c2 cells at a concentration of 20 µM.


Assuntos
Triterpenos , Carpóforos , Lanosterol/farmacologia , Estrutura Molecular , Phellinus , Triterpenos/farmacologia
14.
J Nat Prod ; 84(2): 436-443, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33560122

RESUMO

A new axial chiral binaphtoquinone, hypocrellone (1), and a new perylenequinone, hypomycin F (2), were isolated from the stromata of Hypocrella bambusae, together with five known compounds, 3-7. The structures of 1 and 2 were assigned by spectroscopic and HRESIMS data analyses. The axial chirality of 1 was determined by electronic circular dichroism data analysis, and the absolute configurations of 2 and 3 were determined by X-ray crystallography. The axial chirality of 7 was determined by UV-induced photooxidation from 4. Compounds 1, 4, and 5 showed inhibitory activity against pseudotyped SARS-CoV-2 infection in 293T-ACE2 cells with IC50 values of 0.17, 0.038, and 0.12 µM. Compounds 4 and 5 were also active against live SARS-CoV-2 infection with EC50 values of 0.22 and 0.21 µM, respectively. Further cell-cell fusion assays, surface plasmon resonance assays, and molecular docking studies revealed that 4 and 5 could bind with the receptor-binding domain of SARS-CoV-2 S protein to prevent its interaction with human angiotensin-converting enzyme II receptor. Our results revealed that 4 and 5 are potential SARS-CoV-2 entry inhibitors.


Assuntos
Hypocreales/química , Naftoquinonas/farmacologia , Perileno/análogos & derivados , Quinonas/farmacologia , SARS-CoV-2/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Naftoquinonas/química , Perileno/química , Perileno/farmacologia , Quinonas/química , SARS-CoV-2/fisiologia
15.
Bioorg Med Chem ; 28(18): 115677, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32828420

RESUMO

WAP-8294A2 is a cyclic peptide antibiotic with novel structure and excellent activity against Gram-positive pathogens. Herein, we report the total synthesis of complex macrocyclic peptide WAP-8294A2 (W1), ent-analogue W2, deoxy analogue W3 and de-methyl analogue W4 using a solid-phase synthetic route followed by a final stage solution-phase cyclization reaction. Exploitation of this process allowed the synthesis of eleven alanine-scanning analogues and eight lysine-scanning analogues. The antimicrobial activity of these analogues was evaluated in vitro against Gram-positive bacteria. Based on the MIC results, a primary systematic structure-activity relationship has been established.


Assuntos
Antibacterianos/química , Antibacterianos/síntese química , Depsipeptídeos/química , Depsipeptídeos/síntese química , Aminoácidos/química , Ciclização , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
16.
Nat Prod Res ; 34(2): 204-209, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30580617

RESUMO

A new oleanane triterpenoid, 2α,3ß,6ß,23,29-pentahydroxyolean-12-en-28- oic acid (1), was isolated from the roots of Rhodomyrtus tomentosa, together with four known oleanane triterpenoids (2-5) and two known ursane triterpenoids (6-7). The structure of compound 1 was determined by extensive NMR and HR-ESI-MS data analysis. Compounds 4-5 showed cytotoxicity against PC12 cell lines at a concentration of 50 µM, and compound 1 exhibited moderate neuroprotective activity against corticosterone induced PC12 cell death at the same concentration.


Assuntos
Myrtaceae/química , Ácido Oleanólico/análogos & derivados , Raízes de Plantas/química , Triterpenos/isolamento & purificação , Animais , Citotoxinas/química , Citotoxinas/isolamento & purificação , Humanos , Hidroxilação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Células PC12 , Ratos , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química , Triterpenos/farmacologia
17.
Org Lett ; 21(19): 7919-7922, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31525876

RESUMO

A polyketide-derived alkaloid featuring a unique 3,4-dihydro-2H-indeno[1,2-b]pyridine 1-oxide motif, named phomopsol A (1), and a highly oxidized polyketide containing a new 3,5-dihydro-2H-2,5-methanobenzo[e][1,4]dioxepine moiety, named phomopsol B (2), were isolated from the Thai mangrove endophytic fungus Phomopsis sp. xy21, together with the related biosynthetic polyketide 3. The structures of 1-3 were unambiguously established by single-crystal X-ray diffraction analysis (Cu Kα), and their neuroprotective effects in PC12 cells were evaluated. The biosynthetic origins of 1-3 are proposed.


Assuntos
Fármacos Neuroprotetores/farmacologia , Policetídeos/farmacologia , Animais , Ascomicetos/química , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Modelos Moleculares , Estrutura Molecular , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Células PC12 , Policetídeos/química , Policetídeos/metabolismo , Ratos , Estereoisomerismo , Relação Estrutura-Atividade
19.
Steroids ; 140: 70-76, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30273696

RESUMO

Seven new furostanol saponins (1-7), chongrenosides A-G, were isolated from the rhizomes of Smilax china L., together with nine known furostanol saponins (8-16). The structures of the new furostanol saponins (1-7) were elucidated by extensive spectroscopic data analyses (1D and 2D NMR, HRESIMS) and chemical evidence. Compounds 1-6 and 8-16 were evaluated for TNF-α mRNA expression inhibitory activity on LPS induced RAW264.7 cells. Of them, 1, 4, 6, and 11 inhibited the TNF-α mRNA expression by 88%, 87%, 67%, and 93%, respectively, at the concentration of 10 µM.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Rizoma/química , Saponinas/química , Saponinas/farmacologia , Smilax/química , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Modelos Moleculares , Conformação Molecular , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Saponinas/isolamento & purificação , Fator de Necrose Tumoral alfa/genética
20.
Fitoterapia ; 130: 272-280, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30244033

RESUMO

Nine new ent-abietanes, named decandrols A-I (1-9), which could be categorized into three groups (1, 2-6, 7-9), were isolated from the roots of an Indian mangrove, Ceriops decandra, collected in the swamp of Godavari estuary, Andhra Pradesh, together with six previously reported abietanes (10-15), of which the absolute configurations were first determined. The relative and absolute configurations of these compounds were unambiguously established by HR-ESIMS, extensive 1D and 2D NMR investigations, single-crystal X-ray diffraction analysis with Cu Kα radiation, and quantum-chemical electronic circular dichroism (ECD) calculations. Decandrol A (1) is a rare C9-spirofused 7,8-seco-ent-abietane, whereas 2-15 are typically tricyclic ent-abietanes. Decandrols C (3) and E (5) exhibited significant NF-κB inhibitory activity at the concentration of 100 µM.


Assuntos
Abietanos/química , NF-kappa B/antagonistas & inibidores , Rhizophoraceae/química , Abietanos/isolamento & purificação , Animais , Dicroísmo Circular , Cristalografia por Raios X , Índia , Espectroscopia de Ressonância Magnética , Camundongos , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Raízes de Plantas/química , Células RAW 264.7
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