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1.
J Steroid Biochem Mol Biol ; 242: 106544, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38754521

RESUMEN

Sex steroid hormones such as estrogen estradiol (E2) and androgen dihydrotestosterone (DHT) are involved in the development of hormone-dependent cancers. Blockade of 17ß-hydroxysteroid dehydrogenase type 7 (17ß-HSD7), a member of the short chain dehydrogenase/reductase superfamily, is thought to decrease E2 levels while increasing those of DHT. Therefore, its unique double action makes this enzyme as an interesting drug target for treatment of breast cancer. The chemical synthesis, molecular characterization, and preliminary biological evaluation as 17ß-HSD7 inhibitors of novel carbamate derivatives 3 and 4 are described. Like previous 17ß-HSD7 inhibitors 1 and 2, compounds 3 and 4 bear a hydrophobic nonyl side chain at the C-17ß position of a 4-aza-5α-androstane nucleus, but compound 3 has an oxygen atom replacing the CH2 in the steroid A-ring C-2 position, while compound 4 has a C17-spiranic E-ring containing a carbamate function. They both inhibited the in vitro transformation of estrone (E1) into E2 by 17ß-HSD7, but the introduction of a (17 R)-spirocarbamate is preferable to replacing C-2 methylene with an oxygen atom since compound 4 (IC50 = 63 nM) is an inhibitor 14 times more powerful than compound 3 (IC50 = 900 nM). Furthermore, when compared to the reference inhibitor 1 (IC50 = 111 nM), the use of a C17-spiranic E-ring made it possible to introduce differently the hydrophobic nonyl side chain, without reducing the inhibitory activity.

2.
Molecules ; 29(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38792214

RESUMEN

BACKGROUND: Staphylococcus aureus is a common pathogenic microorganism in humans and animals. Type II NADH oxidoreductase (NDH-2) is the only NADH:quinone oxidoreductase present in this organism and represents a promising target for the development of anti-staphylococcal drugs. Recently, myricetin, a natural flavonoid from vegetables and fruits, was found to be a potential inhibitor of NDH-2 of S. aureus. The objective of this study was to evaluate the inhibitory properties of myricetin against NDH-2 and its impact on the growth and expression of virulence factors in S. aureus. RESULTS: A screening method was established to identify effective inhibitors of NDH-2, based on heterologously expressed S. aureus NDH-2. Myricetin was found to be an effective inhibitor of NDH-2 with a half maximal inhibitory concentration (IC50) of 2 µM. In silico predictions and enzyme inhibition kinetics further characterized myricetin as a competitive inhibitor of NDH-2 with respect to the substrate menadione (MK). The minimum inhibitory concentrations (MICs) of myricetin against S. aureus strains ranged from 64 to 128 µg/mL. Time-kill assays showed that myricetin was a bactericidal agent against S. aureus. In line with being a competitive inhibitor of the NDH-2 substrate MK, the anti-staphylococcal activity of myricetin was antagonized by MK-4. In addition, myricetin was found to inhibit the gene expression of enterotoxin SeA and reduce the hemolytic activity induced by S. aureus culture on rabbit erythrocytes in a dose-dependent manner. CONCLUSIONS: Myricetin was newly discovered to be a competitive inhibitor of S. aureus NDH-2 in relation to the substrate MK. This discovery offers a fresh perspective on the anti-staphylococcal activity of myricetin.


Asunto(s)
Flavonoides , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Flavonoides/farmacología , Flavonoides/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/enzimología , Antibacterianos/farmacología , Antibacterianos/química , NADH Deshidrogenasa/antagonistas & inhibidores , NADH Deshidrogenasa/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Humanos , Factores de Virulencia/antagonistas & inhibidores , Factores de Virulencia/metabolismo
3.
Phys Chem Chem Phys ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809594

RESUMEN

Indole monooxygenases (IMOs) are enzymes from the family of Group E monooxygenases, requiring flavin adenine dinucleotide (FAD) for their activities. IMOs play important roles in both sulfoxidation and epoxidation reactions. The broad substrate range and high selectivity of IMOs make them promising biocatalytic tools for synthesizing chiral compounds. In the present study, quantum chemical calculations using the cluster approach were performed to investigate the reaction mechanism and the enantioselectivity of the IMO from Variovorax paradoxus EPS (VpIndA1). The sulfoxidation of methyl phenyl sulfide (MPS) and the epoxidation of indene were chosen as the representative reactions. The calculations confirmed that the FADOOH intermediate is the catalytic species in the VpIndA1 reactions. The oxidation of MPS adopts a one-step mechanism involving the direct oxygen-transfer from FADOOH to the substrate and the proton transfer from the -OH group back to FAD, while the oxidation of indene follows a stepwise mechanism involving a carbocation intermediate. It was computationally predicted that VpIndA1 prefers the formation of (S)-product for the MPS sulfoxidation and (1S,2R)-product for the indene epoxidation, consistent with the experimental observations. Importantly, the factors controlling the stereo-preference of the two reactions are identified. The findings in the present study provide valuable insights into the VpIndA1-catalyzed reactions, which are essential for the rational design of this enzyme and other IMOs for industrial applications. It is also worth emphasizing that the quantum chemical cluster approach is again demonstrated to be powerful in studying the enantioselectivity of enzymatic reactions.

4.
World J Gastroenterol ; 30(17): 2321-2331, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38813052

RESUMEN

BACKGROUND: The advent of cutting-edge systemic therapies has driven advances in the treatment of hepatocellular carcinoma (HCC), and therapeutic strategies with multiple modes of delivery have been shown to be more efficacious than monotherapy. However, the mechanisms underlying this innovative treatment modality have not been elucidated. AIM: To evaluate the clinical efficacy of targeted therapy plus immunotherapy combined with hepatic arterial infusion chemotherapy (HAIC) of FOLFOX in patients with unresectable HCC. METHODS: We enrolled 53 patients with unresectable HCC who received a combination of targeted therapy, immunotherapy, and HAIC of FOLFOX between December 2020 and June 2021 and assessed the efficacy and safety of the treatment regimen. RESULTS: The objective response rate was 60.4% (32/53), complete response was 24.5% (13/53), partial response was 35.9% (19/53), and stable disease was 39.6% (21/53). The median duration of response and median progression-free survival were 9.1 and 13.9 months, respectively. The surgical conversion rate was 34.0% (18/53), and 1-year overall survival was 83.0% without critical complicating diseases or adverse events (AEs). CONCLUSION: The regimen of HAIC of FOLFOX, targeted therapy, and immunotherapy was curative for patients with unresectable HCC, with no serious AEs and a high rate of surgical conversion.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Hepatocelular , Fluorouracilo , Arteria Hepática , Infusiones Intraarteriales , Leucovorina , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/tratamiento farmacológico , Masculino , Femenino , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Persona de Mediana Edad , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Leucovorina/administración & dosificación , Leucovorina/efectos adversos , Leucovorina/uso terapéutico , Anciano , Adulto , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Compuestos Organoplatinos/uso terapéutico , Resultado del Tratamiento , Terapia Molecular Dirigida/métodos , Supervivencia sin Progresión , Estudios Retrospectivos , Inmunoterapia/métodos , Inmunoterapia/efectos adversos , Terapia Combinada/métodos
5.
Nat Prod Res ; : 1-10, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38635344

RESUMEN

Bioassay-guided purification of the xanthine oxidase (XOD) inhibitory extract of the roots of Ampelopsis japonica resulted in the isolation of two new triterpenoids (1-2), designated Ampejaponoside A and B, along with sixteen known compounds (3-18). The structures of Ampejaposide A and B were elucidated by comprehensive analysis of spectroscopic data with the structures of the known compounds 3-18 confirmed by comparison the spectral data with corresponding values reported in literatures. All the isolates were evaluated for their XOD inhibitory activity in vitro. As a result, compounds 2, 8, and 14-16 displayed significant XOD inhibitory effect, particularly 16 being the most potent with an IC50 value of 0.21 µM, superior to positive substance allopurinol (IC50 1.95 µM). Molecular docking uncovered a unique interaction mode of 16 with the active site of XOD. The current study showed that the triterpenoids and polyphenols from A. japonica could serve as new lead compounds with the potential to speed up the development of novel XOD inhibitors with clinical potential to treat hyperuricaemia and gout.

6.
J Ethnopharmacol ; 330: 118199, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-38631486

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Nocardiosis is an uncommon infectious disease that bears certain similarities to tuberculosis, with a continuous increase in its incidence and a poor prognosis. In traditional Chinese medicine, the leaves of Cajanus cajan (L.) Millsp. are employed to treat wounds, malaria, coughs, and abdominal pain. AIM OF THE STUDY: In this study, we investigated the effects and mechanisms of longistylin A (LGA), a natural stilbene isolated from C. cajan, as a potential antibiotic against nocardiosis. MATERIALS AND METHODS: LGA was isolated from the leaves of C. cajan and assessed using a minimum bactericidal concentration (MBC) determination against Nocardia seriolae. Multi-omics analysis encompassing genes, proteins, and metabolites was conducted to investigate the impact of LGA treatment on N. seriolae. Additionally, quantitative analysis of 40 cytokinins in N. seriolae mycelium was performed to assess the specific effects of LGA treatment on cytokinin levels. Cryo-scanning electron microscopy was utilized to examine morphological changes induced by LGA treatment, particularly in the presence of exogenous trans-zeatin-O-glucoside (tZOG). The therapeutic effect of LGA was investigated by feeding N. seriolae-infected largemouth bass. RESULTS: LGA exhibited significant efficacy against N. seriolae, with MBC value of 2.56 µg/mL. Multi-omics analysis revealed that LGA disrupted glycerophospholipid metabolism and hormone biosynthesis by notably reducing the expression of glycerol-3-phosphate dehydrogenase and calmodulin-like protein. Treatment with LGA markedly disrupted 12 distinct cytokinins in N. seriolae mycelium. Additionally, the addition of exogenous tZOG counteracted the inhibitory effects of LGA on filamentous growth, resulting in mycelial elongation and branching. Furthermore, LGA treatment improved the survival rate of largemouth bass infected with N. seriolae. CONCLUSIONS: We found for the first time that LGA from C. cajan exhibited significant efficacy against N. seriolae by interfering with glycerophospholipid metabolism and cytokinin biosynthesis.


Asunto(s)
Antibacterianos , Cajanus , Citocininas , Glicerofosfolípidos , Nocardia , Nocardia/metabolismo , Nocardia/efectos de los fármacos , Citocininas/farmacología , Citocininas/biosíntesis , Citocininas/metabolismo , Glicerofosfolípidos/metabolismo , Glicerofosfolípidos/biosíntesis , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Hojas de la Planta
7.
Commun Chem ; 7(1): 64, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538750

RESUMEN

Norcoclaurine synthase from Thalictrum flavum (TfNCS) demonstrated high stereospecificity and yield in catalyzing the Pictet-Spengler reaction of dopamine with chiral aldehydes, achieving kinetic resolution of aldehydes. However, the mechanism and the factors contributing to the stereoselectivity remain unclear. Herein, by using quantum chemical calculations, the mechanisms of TfNCS-catalyzed reactions of dopamine with both enantiomers of α-methyl-phenylacetaldehyde are studied. The calculations reveal a mechanism mirroring the reaction of natural substrates, for which the deprotonation of the C5-H of the cyclized intermediate is rate-limiting. The calculated overall barriers are 20.1 kcal mol-1 and 21.6 kcal mol-1 for the reactions of (R)- and (S)-α-methyl-phenylacetaldehyde, respectively. The M97 and L72 residues are proposed to be the key residues contributing to the stereospecificity. The obtained detailed information is helpful for designing new variants of TfNCS with extended substrate scope, and also advancing our understanding of TfNCS reactions for potential applications.

8.
RSC Adv ; 14(11): 7763-7769, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38444970

RESUMEN

Four novel new isocoumarins, cajanolactone B, C, D1 and D2 (1-4), were isolated from ethanolic extracts of the leaves of Cajanus cajan. The structural elucidation has been completed mainly depending on extensive spectroscopic analysis including UV, IR, NMR (1D and 2D), HRESIMS and chiral analysis. Notably, all these new isocoumarins were found to exist in racemic forms, among which compounds 3 and 4 share the same planar structure. This finding suggests that at least the biosynthesis of isocoumarin in C. cajan is chiral tolerant. A plausible biogenetic pathway of compounds 1-4 is proposed.

9.
Nat Commun ; 15(1): 1235, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38336996

RESUMEN

Hemiacetal compounds are valuable building blocks in synthetic chemistry, but their enzymatic synthesis is limited and often hindered by the instability of hemiacetals in aqueous environments. Here, we show that this challenge can be addressed through reaction engineering by using immobilized peroxygenase from Agrocybe aegerita (AaeUPO) under neat reaction conditions, which allows for the selective C-H bond oxyfunctionalization of environmentally significant cyclic ethers to cyclic hemiacetals. A wide range of chiral cyclic hemiacetal products are prepared in >99% enantiomeric excess and 95170 turnover numbers of AaeUPO. Furthermore, by changing the reaction medium from pure organic solvent to alkaline aqueous conditions, cyclic hemiacetals are in situ transformed into lactones. Lactams are obtained under the applied conditions, albeit with low enzyme activity. These findings showcase the synthetic potential of AaeUPO and offer a practical enzymatic approach to produce chiral cyclic hemiacetals through C-H oxyfunctionalization under mild conditions.

10.
Appl Environ Microbiol ; 90(3): e0181823, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38332488

RESUMEN

Zearalenone (ZEN) and its derivatives are estrogenic mycotoxins known to pose significant health threats to humans and animals. Especially, the derivative α-zearalanol (α-ZAL) is over 10 times more toxic than ZEN. Simultaneous degradation of ZEN and its derivatives, especially α-ZAL, using ZEN lactone hydrolases (ZHDs) is a promising solution to eliminate their potential hazards to food safety. However, most available ZHDs exhibit limited activity toward the more toxic α-ZAL compared to ZEN. Here, we identified a broad-substrate spectrum ZHD, named ZHDAY3, from Exophiala aquamarina CBS 119918, which could not only efficiently degrade ZEN but also exhibited 73% relative activity toward α-ZAL. Through rational design, we obtained the ZHDAY3(N153H) mutant, which exhibited the highest specific activity (253.3 ± 4.3 U/mg) reported so far for degrading α-ZAL. Molecular docking, structural comparative analysis, and kinetic analysis collectively suggested that the shorter distance between the side chain of the catalytic residue His242 and the lactone bond of α-ZAL and the increased binding affinity to the substrate were mainly responsible for the improved catalytic activity of ZHDAY3(N153H) mutant. This mechanism was further validated through additional molecular docking of 18 mutants and experimental verification of six mutants.IMPORTANCEThe mycotoxins zearalenone (ZEN) and its derivatives pose a significant threat to food safety. Here, we present a highly promising ZEN lactone hydrolase (ZHD), ZHDAY3, which is capable of efficiently degrading both ZEN and the more toxic derivative α-ZAL. Next, the ZHDAY3(N153H) mutant obtained by single-point mutation exhibited the highest specific activity for degrading α-ZAL reported thus far. We further elucidated the molecular mechanisms underlying the enhanced hydrolytic activity of ZHDAY3(N153H) toward α-ZAL. These findings represent the first investigation on the molecular mechanism of ZHDs against α-ZAL and are expected to provide a significant reference for further rational engineering of ZHDs, which will ultimately contribute to addressing the health risks and food safety issues posed by ZEN-like mycotoxins.


Asunto(s)
Micotoxinas , Zearalenona , Zeranol , Humanos , Animales , Zearalenona/química , Zearalenona/metabolismo , Zeranol/química , Zeranol/metabolismo , Lactonas , Mutación Puntual , Hidrolasas/metabolismo , Simulación del Acoplamiento Molecular , Cinética , Micotoxinas/metabolismo
11.
Liver Int ; 44(4): 894-906, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38263714

RESUMEN

BACKGROUND & AIMS: We aimed to develop a Transformer-based deep learning (DL) network for prognostic stratification in hepatocellular carcinoma (HCC) patients undergoing RFA. METHODS: A Swin Transformer DL network was trained to establish associations between magnetic resonance imaging (MRI) datasets and the ground truth of microvascular invasion (MVI) based on 696 surgical resection (SR) patients with solitary HCC ≤3 cm, and was validated in an external cohort (n = 180). The multiphase MRI-based DL risk outputs using an optimal threshold of .5 was employed as a MVI classifier for prognosis stratification in the RFA cohort (n = 180). RESULTS: Over 90% of all enrolled patients exhibited hepatitis B virus infection. Liver cirrhosis was significantly more prevalent in the RFA cohort compared to the SR cohort (72.2% vs. 44.1%, p < .001). The MVI risk outputs exhibited good performance (area under the curve values = .938 and .883) for predicting MVI in the training and validation cohort, respectively. The RFA patients at high risk of MVI classified by the MVI classifier demonstrated significantly lower recurrence-free survival (RFS) and overall survival rates at 1, 3 and 5 years compared to those classified as low risk (p < .001). Multivariate cox regression modelling of a-fetoprotein > 20 ng/mL [hazard ratio (HR) = 1.53; 95% confidence interval (95% CI): 1.02-2.33, p = .047], high risk of MVI (HR = 3.76; 95% CI: 2.40-5.88, p < .001) and unfavourable tumour location (HR = 2.15; 95% CI: 1.40-3.29, p = .001) yielded a c-index of .731 (bootstrapped 95% CI: .667-.778) for evaluating RFS after RFA. Among the three risk factors, MVI was the most powerful predictor for intrahepatic distance recurrence. CONCLUSIONS: The proposed MVI classifier can serve as a valuable imaging biomarker for prognostic stratification in early-stage HCC patients undergoing RFA.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ablación por Radiofrecuencia , Humanos , Pronóstico , Neoplasias Hepáticas/patología , Estudios Retrospectivos , Invasividad Neoplásica
12.
Nat Prod Res ; : 1-8, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38164765

RESUMEN

Three new stilbenoids, namely two rare plant-derived phenanthrenes denominated Cajananthrenes A and B (1, 2) and one bibenzyl named Cajanbenzyl (3), together with a diphenyl ether derivative designated Cajanether (4), as well as five other known compounds (5-9) were isolated from the ethanolic extract of the leaves of Cajanus cajan. Their structures were determined through extensive spectroscopic analysis including UV, IR, NMR (1D and 2D) and HRESIMS as well. A plausible biogenesis pathway was proposed for the biosynthesis of compounds 1-3. Compounds 1 and 2 displayed moderate anti-inflammatory activity as evident from the inhibitory effect on NO production in LPS-stimulated RAW 264.7 macrophages with IC50 values of 73.6 and 44.6 µM respectively.

13.
ChemistryOpen ; : e202300256, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38224208

RESUMEN

The acyltransferase from Pseudomonas protegens (PpATase) catalyzes in nature the reversible transformation of monoacetylphloroglucinol to diacetylphloroglucinol and phloroglucinol. Interestingly, this enzyme has been shown to catalyze the promiscuous transformation of 3-hydroxyphenyl acetate to 2',4'-dihydroxyacetophenone, representing a biological version of the Fries rearrangement. In the present study, we report a mechanistic investigation of this activity of PpATase using quantum chemical calculations. A detailed mechanism is proposed, and the energy profile for the reaction is presented. The calculations show that the acylation of the enzyme is highly exothermic, while the acetyl transfer back to the substrate is only slightly exothermic. The deprotonation of the C6-H of the substrate is rate-limiting, and a remote aspartate residue (Asp137) is proposed to be the general base group in this step. Analysis of the binding energies of various acetyl acceptors shows that PpATase can promote both intramolecular and intermolecular Fries rearrangement towards diverse compounds.

14.
Sci Total Environ ; 917: 170090, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38246380

RESUMEN

The growing trend of land-based aquaculture has heightened the significance of comprehensively assessing air-water carbon dioxide (CO2) gas exchange in these inland waters, given their potential impact on carbon neutral strategies. However, temporal variations of partial pressure of CO2 (pCO2) and CO2 flux in clam and fish aquaculture ponds were barely investigated. We assessed the water surface pCO2 in one to five months intervals by deploying a lab-made buoy in three clam ponds and three fishponds located in tropical and subtropical climates. Measurements were conducted over a 24 h period each time, spanning from April 2021 to June 2022, covering the stocking, middle, and harvesting stages of the culture cycle. Diurnal pCO2 variations were dominantly controlled by biologically driven changes in dissolved inorganic carbon and total alkalinity (~97 %), while temperature and salinity effects were minor (~3 %). Clam ponds acted as a sink of atmospheric CO2 during stocking stages and transitioned to a source during middle to harvesting stages. In contrast, fishponds acted as a source of atmospheric CO2 throughout culture cycles and CO2 flux strengthened when reaching harvesting stages. Overall, clam ponds acted as a weak sink for atmospheric CO2 (-2.8 ± 17.3 mmol m-2 d-1), whereas fishponds acted as a source (16.8 ± 21.7 mmol m-2 d-1). CO2 emission was stronger during daytime coinciding with higher windspeeds compared to nighttime in fishponds. We suggest incorporating high temporal resolution measurements to account for diurnal and culture-stage variations, enabling more accurate estimates of air-water CO2 flux in aquaculture ponds. Moreover, the findings of this study highlight the importance of feeding, aeration, and biological activities (photosynthesis, remineralization, and calcification) in controlling the air-water CO2 flux in aquaculture ponds and such information can be used in implementing better strategies to achieve carbon neutral goals.


Asunto(s)
Dióxido de Carbono , Monitoreo del Ambiente , Animales , Dióxido de Carbono/análisis , Estanques , Agua , Metano/análisis , Acuicultura
15.
Plant Foods Hum Nutr ; 79(1): 66-72, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37994988

RESUMEN

Bioactive peptides derived from proteins found in various foods provide significant health benefits, including regulating blood sugar levels by inhibiting carbohydrate-hydrolyzing enzymes. Hydrolysates of peanut protein were prepared using alcalase (AH) or trypsin (TH) to generate antidiabetic peptides with high activity against α-amylase (IC50 of 6.46 and 5.71 mg/mL) and α-glucosidase (IC50 of 6.30 and 5.57 mg/mL), as well as antiradical activity to scavenge DPPH• (IC50 of 4.18 and 3.12 mg/mL) and ABTS•+ (IC50 of 2.87 and 2.56 mg/mL), respectively. The bioactivities of hydrolysates were greatest in the ultrafiltration-generated F3 fraction (< 3 kDa). The most active fraction was TH-F3, which was purified by gel filtration chromatography to generate sub-fractions (SF). With IC50 values of 1.05 and 0.69 mg/mL, the F3-SF8 fraction was the most effective at inhibiting the activity of α-amylase and α-glucosidase, respectively. This fraction was further purified using RP-HPLC to generate sub-subfractions (SSF), the most active of which were F3-SF8-SSF9 and SSF10. The peptide sequences F3-SF8-SSF9 and SSF10 were determined using LC-MS/MS. Two novel antidiabetic peptides with the potential to inhibit α-amylase and α-glucosidase were identified, with the sequences Asp-Trp-Arg (476.22 Da, IC50 of 0.78, and 0.35 mg/mL) and Phe-Tyr (329.15 Da, IC50 of 0.91, and 0.41 mg/mL). These results suggest that peptides derived from peanut protein are attractive natural ingredients for diabetes management applications.


Asunto(s)
Arachis , Hipoglucemiantes , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , Arachis/metabolismo , alfa-Glucosidasas/metabolismo , Cromatografía Liquida , Espectrometría de Masas en Tándem , Péptidos/farmacología , alfa-Amilasas
16.
Mol Phylogenet Evol ; 190: 107956, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37898296

RESUMEN

Phylogenomic conflicts are widespread among genomic data, with most previous studies primarily focusing on nuclear datasets instead of organellar genomes. In this study, we investigate phylogenetic conflict analyses within and between plastid and mitochondrial genomes using Potentilla as a case study. We generated three plastid datasets (coding, noncoding, and all-region) and one mitochondrial dataset (coding regions) to infer phylogenies based on concatenated and multispecies coalescent (MSC) methods. Conflict analyses were then performed using PhyParts and Quartet Sampling (QS). Both plastid and mitochondrial genomes divided the Potentilla into eight highly supported clades, two of which were newly identified in this study. While most organellar loci were uninformative for the majority of nodes (bootstrap value < 70%), PhyParts and QS detected conflicting signals within the two organellar genomes. Regression analyses revealed that conflict signals mainly occurred among shorter loci, whereas longer loci tended to be more concordant with the species tree. In addition, two significant disagreements between the two organellar genomes were detected, likely attributed to hybridization and/or incomplete lineage sorting. Our results demonstrate that mitochondrial genes can fully resolve the phylogenetic relationships among eight major clades of Potentilla and are not always linked with plastome in evolutionary history. Stochastic inferences appear to be the primary source of observed conflicts among the gene trees. We recommend that the loci with short sequence length or containing limited informative sites should be used cautiously in MSC analysis, and suggest the joint application of concatenated and MSC methods for phylogenetic inference using organellar genomes.


Asunto(s)
Genoma Mitocondrial , Genoma de Plastidios , Potentilla , Rosaceae , Filogenia , Potentilla/genética , Rosaceae/genética , Plastidios/genética
17.
Angew Chem Int Ed Engl ; 63(7): e202318550, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38155101

RESUMEN

Noncanonical amino acids (ncAAs) containing tertiary alcohols are valuable as precursors of natural products and active pharmaceutical ingredients. However, the assembly of such ncAA scaffolds from simple material by C-C bond formation remains a challenging task due to the presence of multiple stereocenters and large steric hindrance. In this study, we present a novel solution to this problem through highly selective enzymatic decarboxylative aldol addition. This method allows for the streamlined assembly of multifunctionalized ncAAs with γ-tertiary alcohols from readily available materials, such as L -aspartatic acid and isatins, vicinal diones and keto esters. The modularity of electrophiles furnished four classes of ncAAs with decent efficiency as well as excellent site and stereocontrol. Computational modeling was employed to gain detailed insight into the catalytic mechanism and to provide a rationale for the observed selectivities. The method offers a single-step approach to producing multifunctionalized ncAAs, which can be directly utilized in peptide synthesis and bioactivity assessment.


Asunto(s)
Alcoholes , Aminoácidos , Aminoácidos/química , Catálisis
18.
Cancer Commun (Lond) ; 44(1): 127-172, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38160327

RESUMEN

The 2023 update of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for Gastric Cancer focuses on standardizing cancer diagnosis and treatment in China, reflecting the latest advancements in evidence-based medicine, healthcare resource availability, and precision medicine. These updates address the differences in epidemiological characteristics, clinicopathological features, tumor biology, treatment patterns, and drug selections between Eastern and Western gastric cancer patients. Key revisions include a structured template for imaging diagnosis reports, updated standards for molecular marker testing in pathological diagnosis, and an elevated recommendation for neoadjuvant chemotherapy in stage III gastric cancer. For advanced metastatic gastric cancer, the guidelines introduce new recommendations for immunotherapy, anti-angiogenic therapy and targeted drugs, along with updated management strategies for human epidermal growth factor receptor 2 (HER2)-positive and deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) patients. Additionally, the guidelines offer detailed screening recommendations for hereditary gastric cancer and an appendix listing drug treatment regimens for various stages of gastric cancer. The 2023 CSCO Clinical Guidelines for Gastric Cancer updates are based on both Chinese and international clinical research and expert consensus to enhance their applicability and relevance in clinical practice, particularly in the heterogeneous healthcare landscape of China, while maintaining a commitment to scientific rigor, impartiality, and timely revisions.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Oncología Médica , Inmunoterapia , Terapia Neoadyuvante , China
19.
Pharmacol Res ; 197: 106973, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37898441

RESUMEN

Immunogenic cell death (ICD), one of cell-death types through release of damage-associated molecular patterns from dying tumor cells, activates tumor-specific immune response and elicits anti-tumor immunity by traditional radiotherapy and chemotherapy. However, whether natural products could induce ICD in leukemia is not elucidated. Here, we report dietary γ-mangostin eradicates murine primary leukemic cells and prolongs the survival of leukemic mice. As well, it restrains primary leukemic cells and CD34+ leukemic progenitor cells from leukemia patients. Strikingly, γ-mangostin attenuates leukemic cells by inducing ICD as characterized by expression of HSP90B1, ANXA1 and IL1B. Additionally, γ-mangostin accelerates cytoplasmic chromatin fragments generation, promoting DNA damage response, and enhances cGAS activation, leading to up-regulation of chemokines. Meanwhile, it induces HDAC4 degradation and acetylated histone H3 accumulation, which promotes chemokines transcription. Ultimately, CD8+ T cell is activated and recruited by γ-mangostin-induced chemokines in the microenvironment. Our study identifies γ-mangostin triggers ICD and activates cGAS signaling through DNA damage response and epigenetic modification. Therefore, dietary γ-mangostin would act as a potential agent to provoke anti-tumor immunity in the prevention and treatment of leukemia.


Asunto(s)
Muerte Celular Inmunogénica , Leucemia Mieloide Aguda , Humanos , Animales , Ratones , Leucemia Mieloide Aguda/tratamiento farmacológico , Dieta , Quimiocinas , Microambiente Tumoral
20.
Front Pharmacol ; 14: 1246657, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37663264

RESUMEN

Background: A number of patients with Crohn's disease (CD) suffer from loss of response to infliximab (IFX) therapy. Splenic volume is reported to be enlarged in patients with CD compared to normal individuals. The association between splenic volume and IFX efficacy in CD remains unclear. Methods: We performed a retrospective study of patients with CD who received regular IFX treatment at Zhongshan Hospital, Fudan University, between August 2015 and December 2021. We collected baseline characteristics and clinical features from medical records in the CD database of Zhongshan Hospital. We accurately measured the splenic volume using semi-auto spleen segmentation software, followed by the analysis of splenic volume and IFX efficacy. Results: We included 49 patients with CD receiving IFX treatment, of whom 41 responded to IFX and 8 failed to respond to IFX. Splenic volume, as well as volume adjusted for body mass index (SV/BMI) and body weight (SV/W), was significantly decreased after IFX treatment in responders but increased in non-responders compared to the volume before the treatment. Accordingly, the levels of leukocyte count, platelet count, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were decreased after IFX treatment in responders. Contrarily, the levels of hemoglobin, albumin, and tumor necrosis factor (TNF)-α were elevated in responders. Moreover, both CRP and TNF-α levels were significantly positively correlated with SV/BMI in all patients. Conclusion: Splenic volume, especially SV/BMI and SV/W, was reduced after IFX treatment in CD patients responsive to IFX. SV/BMI was positively correlated with disease activity. Splenic volume is a promising indicator to evaluate IFX efficacy in CD.

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