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1.
Int J Biol Macromol ; 267(Pt 2): 131320, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38569989

RESUMEN

Macrofungi, a class of unique natural resources, are gaining popularity owing to their potential therapeutic benefits and edibility. From Fomitopsis officinalis, a medicinal macrofungus with anticancer activity, a homogeneous heteropolysaccharide (FOBP50-1) with a molecular weight of 2.21 × 104 g/mol has been extracted and purified. FOBP50-1 was found to be composed of 3-O-methylfucose, fucose, mannose, glucose, and galactose with a ratio of 1: 6.5: 4.4: 8.1: 18.2. The sugar fragments and structure of FOBP50-1 were investigated, which included →6)-α-d-Galp-(1→, →2,6)-α-d-Galp-(1→, →3)-α-l-Fucp-(1→, α-d-Glcp-(1→, →3)-ß-d-Manp-(1→, →6)-ß-d-Manp-(1→, 3-O-Me-α-l-Fucp-(1→, according to the UV, FT-IR, GC-MS, and NMR data. Besides the structure elucidation, FOBP50-1 showed promising antitumor activity in the zebrafish assays. The following mechanism examination discovered that FOBP50-1 interacted with TLR-4, PD-1, and VEGF to activate immunity and inhibit angiogenesis according to a series of cell, transgenic zebrafish, and surface plasmon resonance (SPR) experiments. The KD values indicating the association of FOBP50-1 with TLR-4, PD-1, and VEGF, were 4.69 × 10-5, 7.98 × 10-6, 3.04 × 10-6 M, respectively, in the SPR experiments. All investigations have demonstrated that the homogenous fungal polysaccharide FOBP50-1 has the potential to be turned into a tumor immunotherapy agent.


Asunto(s)
Inhibidores de la Angiogénesis , Antineoplásicos , Polisacáridos Fúngicos , Pez Cebra , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/farmacología , Polisacáridos Fúngicos/aislamiento & purificación , Animales , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/química , Inhibidores de la Angiogénesis/aislamiento & purificación , Humanos , Coriolaceae/química , Neovascularización Patológica/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ratones , Angiogénesis
2.
Int J Biol Macromol ; 263(Pt 2): 130242, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38368974

RESUMEN

Glehnia littoralis is an edible plant with significant medicinal value. To further elucidate the potential functional components for developing antitumor agents or functional foods, the polysaccharides in this plant were investigated, and a homogeneous polysaccharide, GLP90-2, was obtained through extraction and ethanol precipitation. By employing methylation, GC-MS, FT-IR, and NMR analysis, GLP90-2 was identified as an arabinan having a molecular weight of 7.76 × 103 g/mol and consisting of three types of residues: α-l-Araf-(1→, →5)-α-l-Araf-(1→, and →3,5)-α-l-Araf-(1→. The subsequent functional analysis revealed that GLP90-2 suppressed tumor development and metastasis in a zebrafish model. Mechanistic studies have shown that GLP90-2 promoted the maturation of DC2.4 cells and macrophages and enhanced the expression of immune-related cytokines, which may be attributed to the interaction between GLP90-2 and TLR-4. Additionally, GLP90-2 exhibited a strong interaction with PD-1, contributing to the activation of immunity. Furthermore, GLP90-2 suppressed angiogenesis in the transgenic zebrafish model, and this impact may be ascribed to the modulation of the VEGF/VEGFR-2 signaling pathway. All the results indicate that GLP90-2 demonstrates a strong tumor immunotherapy effect in vivo and has high potential for development.


Asunto(s)
Apiaceae , Neoplasias , Animales , Pez Cebra , Espectroscopía Infrarroja por Transformada de Fourier , Angiogénesis , Polisacáridos/farmacología , Polisacáridos/química
3.
ACS Omega ; 9(5): 5616-5623, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38343945

RESUMEN

Three new pimarane diterpenoids, libertellenones U-W (1-3), together with libertellenone C (4) and myrocin A (5) were isolated from an EtOAc-extract of Apiospora arundinis culture medium. The chemical structures of the new compounds were elucidated using MS, NMR, and CD spectroscopic data. Benign prostatic hyperplasia (BPH), the abnormal and pathological proliferation of epithelial and stromal cells in prostatic tissues, is a common disease in middle-aged and elderly men. In this study, the anti-BPH effects of myrocin A (5) were evaluated using BPH-1 and WPMY-1 cells. Treatment with myrocin A (5) exerted antiproliferative effects in BPH-1 and dihydrotestosterone (DHT)-stimulated WPMY-1 cells. In BPH, treatment with myrocin A (5) significantly suppressed the mRNA levels of androgen receptor (AR) and its downstream targets nuclear receptor coactivator 1 (NCOA1), proliferating cell nuclear antigen (PCNA) and kallikrein-related peptidase 3 (KLK3). Additionally, DHT-stimulated WPMY-1 cells demonstrated an upregulated mRNA levels of AR, NCOA1, PCNA, and KLK3. However, treatment with myrocin A (5) resulted in suppression of the mRNA levels. Moreover, myrocin A (5) docked computationally into the binding site of the androgen receptor (-5.5 kcal/mol).

4.
Carbohydr Polym ; 331: 121831, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38388048

RESUMEN

An undisclosed polysaccharide, BCP80-2, was isolated from Belamcanda chinensis (L.) DC. Structural investigation revealed that BCP80-2 consists of ten monosaccharide residues including t-α-Araf-(1→, →3,5)-α-Araf-(1→, →5)-α-Araf-(1→, →4)-ß-Xylp-(1→, →3)-α-Rhap-(1→, →4)-ß-Manp-(1→, t-ß-Glcp-(1→, →6)-α-Glcp-(1→, t-ß-Galp-(1→, and→3)-α-Galp-(1→. In vivo activity assays showed that BCP80-2 significantly suppressed neoplasmic growth, metastasis, and angiogenesis in zebrafish. Mechanistic studies have shown that BCP80-2 inhibited cell migration of HepG2 cells by suppressing the FAK signaling pathway. Moreover, BCP80-2 also activated immunomodulation and upregulated the secretion of co-stimulatory molecules CD40, CD86, CD80, and MHC-II. In conclusion, BCP80-2 inhibited tumor progression by targeting the FAK signaling pathway and activating CD40-induced adaptive immunity.


Asunto(s)
Arabinosa , Neoplasias Hepáticas , Animales , Secuencia de Carbohidratos , Pez Cebra , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Polisacáridos/química , Neoplasias Hepáticas/tratamiento farmacológico
5.
J Antibiot (Tokyo) ; 77(4): 257-263, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38243062

RESUMEN

Using mass spectrometry (MS)-guided isolation methods, a new thiodiketopiperazine derivative (1) and exserohilone (2) were isolated from an EtOAc-extract of Setosphaeria rostrata culture medium. The chemical structure of the new compound was elucidated by MS and NMR spectroscopy, and the absolute configurations were established by the quantum mechanical calculations of electronic circular dichroism. All isolated compounds were examined for their effects on reactive oxygen species (ROS) production, matrix metalloproteinase 1 (MMP-1) secretion, and procollagen type I α1 secretion in tumor necrosis factor (TNF)-α-induced human dermal fibroblasts. Compound 1 and exserohilone (2) exhibited the inhibition of TNF-α-induced ROS generation and MMP-1 secretion. Additionally, compound 1 and exserohilone (2) increased the procollagen type I α1 secretion. Compound 1 docked computationally into the active site of MMP-1 (-6.0 kcal/mol).


Asunto(s)
Ascomicetos , Metaloproteinasa 1 de la Matriz , Factor de Necrosis Tumoral alfa , Humanos , Metaloproteinasa 1 de la Matriz/farmacología , Especies Reactivas de Oxígeno , Fibroblastos
6.
Bioorg Chem ; 143: 107070, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38190796

RESUMEN

Three new fusidane-type nortriterpenoids, simplifusinolide A, 24-epi simplifusinolide A, and simplifusidic acid L (1-3), were isolated from the EtOAc extract of the Arctic marine-derived fungus Simplicillium lamellicola culture medium, together with fusidic acid (4) and 16-O-deacetylfusicid acid (5). The structures of the isolated compounds were elucidated by NMR and MS analyses. The absolute configurations of compounds 1-3 were established by the quantum mechanical calculations of electronic circular dichroism and gauge-including atomic orbital NMR chemical shifts, followed by DP4 + analysis. Benign prostatic hyperplasia (BPH) is a major urological disorder in men worldwide. The anti-BPH potentials of the isolated compounds were evaluated using BPH-1 and WPMY-1 cells. Treatment with simplifusidic acid L (3) and fusidic acid (4) significantly downregulated the mRNA levels of the androgen receptor (AR) and its downstream effectors, inhibiting the proliferation of BPH-1 cells. Specifically, treatment with 24-epi simplifusinolide A (2) significantly suppressed the cell proliferation of both BPH-1 and DHT-stimulated WPMY-1 cells by inhibiting AR signaling. These results suggest the potential of 24-epi simplifusinolide A (2), simplifusidic acid L (3) and fusidic acid (4) as alternative agents for BPH treatment by targeting AR signaling.


Asunto(s)
Hypocreales , Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/tratamiento farmacológico , Ácido Fusídico/farmacología , Extractos Vegetales/farmacología , Proliferación Celular
7.
Int J Biol Macromol ; 256(Pt 1): 128057, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956805

RESUMEN

Fucoidan (FU), a natural marine polysaccharide, is an immunomodulator with great potential in tumor immunotherapy. In this work, a FU encapsulated nanoparticle named QU@FU-TS was developed, which contained the anticancer phytochemical quercetin (QU) and had the potential for cancer chemo-immunotherapy. QU@FU-TS were constructed through molecular self-assembly using green material tea saponin (TS) as the linking molecule. The molecular dynamics (MD) simulation showed that QU was bound to the hydrophobic tail of TS. At the same time, FU spontaneously assembled with the hydrophilic head of TS to form the outer layer of the QU@FU-TS. The molecular interactions between QU and TS were mainly π-stacking and hydrogen bonds. The bonding of FU and TS was maintained through the formation of multiple hydrogen bonds between the sulfate ester group and the hydroxy group. The inhibitory effects of QU@FU-TS on A549 cell proliferation were more potent than that by free QU. The antitumor activity of QU@FU-TS was mediated through various mechanisms, including the induction of oxidative stress, blocking cell cycle progression, and promoting cell apoptosis. Moreover, QU@FU-TS has been demonstrated to impede the proliferation and migration of cancer cells in vivo. The expression levels of macrophage surface markers increased under the treatment of QU@FU-TS, suggesting the potential of QU@FU-TS to serve as an immunotherapeutic agent by promoting macrophage activation.


Asunto(s)
Nanopartículas , Neoplasias , Quercetina/farmacología , Quercetina/uso terapéutico , Quercetina/química , Línea Celular Tumoral , Nanopartículas/química , Polisacáridos/farmacología , Inmunoterapia , Neoplasias/tratamiento farmacológico
8.
Int J Biol Macromol ; 255: 127854, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37935290

RESUMEN

In recent years, the application of nanoparticles formed by coupling metal nanomaterials of photothermal therapy with polysaccharides as modified carriers in the targeted treatment of liver cancer has attracted extensive attention. In the present work, an undescribed homogeneous polysaccharide BCP50-2 was obtained from Belamcanda chinensis (L.) DC. The structural analysis displayed that BCP50-2 contained galactose and a small amount of arabinose, and was mainly composed of six monosaccharide residues: →3,5)-α-l-Araf-(1→, →4)-ß-d-Galp-(1→, →4,6)-ß-d-Galp-(1→, →3)-α-l-Galp-(1→, terminal α-l-Araf, and terminal ß-d-Galp. To enhance the antitumor activity of BCP50-2, BCP50-2-AuNRs were prepared by coupling BCP50-2 with gold nanorods for the treatment of liver cancer. BCP50-2-AuNRs were rod-shaped with a long diameter of 26.8 nm and had good photothermal conversion effects. Under near-infrared (NIR) light irradiation, BCP50-2-AuNRs possessed photothermal effects and suppressed the growth of HepG2, A549, and MCF-7 cells. In addition, BCP50-2-AuNRs inhibited the development of liver cancer by inducing cell apoptosis, arresting the cell cycle in G2/M phases, and inhibiting cell migration. Moreover, BCP50-2-AuNRs inhibited tumor proliferation, migration, and angiogenesis in zebrafish. In summary, BCP50-2-AuNRs may be potentially useful for cancer treatment.


Asunto(s)
Neoplasias Hepáticas , Nanotubos , Animales , Terapia Fototérmica , Fototerapia , Oro/química , Pez Cebra , Nanotubos/química , Neoplasias Hepáticas/terapia , Polisacáridos/farmacología , Línea Celular Tumoral
9.
Molecules ; 28(23)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38067413

RESUMEN

Cancer is one of the deadliest human diseases, causing high rates of illness and death. Lung cancer has the highest mortality rate among all malignancies worldwide. Effusanin B, a diterpenoid derived from Isodon serra, showed therapeutic potential in treating non-small-cell lung cancer (NSCLC). Further research on the mechanism indicated that effusanin B inhibited the proliferation and migration of A549 cells both in vivo and in vitro. The in vitro activity assay demonstrated that effusanin B exhibited significant anticancer activity. Effusanin B induced apoptosis, promoted cell cycle arrest, increased the production of reactive oxygen species (ROS), and altered the mitochondrial membrane potential (MMP). Based on mechanistic studies, effusanin B was found to inhibit the proliferation and migration of A549 cells by affecting the signal transducer and activator of transcription 3 (STAT3) and focal adhesion kinase (FAK) pathways. Moreover, effusanin B inhibited tumor growth and spread in a zebrafish xenograft model and demonstrated anti-angiogenic effects in a transgenic zebrafish model.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Animales , Humanos , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Pez Cebra/metabolismo , Transducción de Señal , Angiogénesis , Proliferación Celular , Apoptosis , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Factor de Transcripción STAT3/metabolismo
10.
Molecules ; 28(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37894550

RESUMEN

Aimed at discovering small molecules as anticancer drugs or lead compounds from plants, a lindenane-type sesquiterpene dimer, chlorahololide D, was isolated from Chloranthus holostegius. The literature review showed that there were few reports on the antitumor effects and mechanisms of chlorahololide D. Our biological assay suggested that chlorahololide D blocked the growth and triggered apoptosis of MCF-7 cells by stimulating the reactive oxygen species (ROS) levels and arresting the cell cycle at the G2 stage. Further mechanism exploration suggested that chlorahololide D regulated apoptosis-related proteins Bcl-2 and Bax. Moreover, chlorahololide D inhibited cell migration by regulating the FAK signaling pathway. In the zebrafish xenograft model, chlorahololide D was observed to suppress tumor proliferation and migration significantly. Considering the crucial function of angiogenesis in tumor development, the anti-angiogenesis of chlorahololide D was also investigated. All of the research preliminarily revealed that chlorahololide D could become an anti-breast cancer drug.


Asunto(s)
Neoplasias de la Mama , Magnoliopsida , Sesquiterpenos , Animales , Humanos , Femenino , Estructura Molecular , Neoplasias de la Mama/tratamiento farmacológico , Pez Cebra/metabolismo , Magnoliopsida/metabolismo , Apoptosis , Proliferación Celular , Línea Celular Tumoral , Células MCF-7
11.
Phytochemistry ; 216: 113867, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37757926

RESUMEN

Four undescribed cycloartane-type triterpenoids (1-4) and seven undescribed steroids (6-12), along with five known analogues (5 and 13-16), were isolated from the leaves of Trichilia connaroides. Their structures were identified based on the NMR data and HRESIMS, and the absolute configurations were determined through single-crystal X-ray diffraction analysis, Mosher's method, and ECD calculations. The multidrug resistance (MDR) reversal activities of all the isolates were assessed, and compounds 10 and 11 showed significant activities to reverse the MDR of MCF-7/DOX cells with IC50 values of 2.90 and 3.76 µM, respectively. These bioactive compounds may bring fresh insights into the research and development of MDR reversal agents.


Asunto(s)
Limoninas , Meliaceae , Triterpenos , Estructura Molecular , Limoninas/química , Triterpenos/farmacología , Triterpenos/química , Meliaceae/química , Esteroides/farmacología
12.
Int J Biol Macromol ; 246: 125555, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37364807

RESUMEN

Polysaccharides, an important class of carbohydrate polymers, are considered as one of the sources of drug molecules. To discover bioactive polysaccharides as potential agents against cancer, a homogeneous polysaccharide (IJP70-1) has been purified from the flowers of Inula japonica, which is a traditional medicinal plant used for various medical indications. IJP70-1 with a molecular weight of 1.019 × 105 Da was mainly composed of →5)-α-l-Araf-(1→, →2,5)-α-l-Araf-(1→, →3,5)-α-l-Araf-(1→, →2,3,5)-α-l-Araf-(1→, →6)-α-d-Glcp-(1→, →3,6)-α-d-Galp-(1→, and t-α-l-Araf. Apart from the characteristics and structure elucidated by various techniques, the in vivo antitumor activity of IJP70-1 was assayed using zebrafish models. In the subsequent mechanism investigation, it was found that the in vivo antitumor activity of IJP70-1 was not cytotoxic mechanism caused, but related to the activation of the immune system and inhibition of angiogenesis by interacting with the proteins toll-like receptor-4 (TLR-4), programmed death receptor-1 (PD-1), and vascular endothelial growth factor (VEGF). The chemical and biological studies have shown that the homogeneous polysaccharide IJP70-1 has the potential to be developed into an anticancer agent.


Asunto(s)
Antineoplásicos , Inula , Animales , Factor A de Crecimiento Endotelial Vascular , Receptor de Muerte Celular Programada 1 , Receptor Toll-Like 4 , Pez Cebra , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/química , Factores de Crecimiento Endotelial Vascular , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Polisacáridos/química
13.
Phytochemistry ; 212: 113720, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37187247

RESUMEN

A phytochemical investigation led to the isolation of five undescribed compounds (1-5) from the methanol extract of the rhizomes and roots of Patrinia heterophylla. The structures and configurations of these compounds were characterized by HRESIMS, ECD, and NMR data analyses. These compounds were assayed for their anti-inflammatory potential using LPS-stimulated BV-2 cells, of which compound 4 showed strong nitric oxide (NO) inhibitory effects with an IC50 of 6.48 µM. The potential anti-inflammatory mechanism was examined utilizing Western blotting and molecular docking. Further in vivo anti-inflammatory experiments revealed that compound 4 inhibited the NO production and reactive oxygen species in the zebrafish model.


Asunto(s)
Patrinia , Animales , Patrinia/química , Iridoides/química , Simulación del Acoplamiento Molecular , Pez Cebra , Antiinflamatorios/farmacología , Óxido Nítrico , Estructura Molecular
14.
J Am Chem Soc ; 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37023253

RESUMEN

Glucose, a critical source of energy, directly determines the homeostasis of the human body. However, due to the lack of robust imaging probes, the mechanism underlying the changes of glucose homeostasis in the human body remains unclear. Herein, diboronic acid probes with good biocompatibility and high sensitivity were synthesized based on an ortho-aminomethylphenylboronic acid probe, phenyl(di)boronic acid (PDBA). Significantly, by introducing the water-solubilizing group -CN directly opposite the boronic acid group and -COOCH3 or -COOH groups to the ß site of the anthracene in PDBA, we obtained the water-soluble probe Mc-CDBA with sensitive response (F/F0 = 47.8, detection limit (LOD) = 1.37 µM) and Ca-CDBA with the highest affinity for glucose (Ka = 4.5 × 103 M-1). On this basis, Mc-CDBA was used to identify glucose heterogeneity between normal and tumor cells. Finally, Mc-CDBA and Ca-CDBA were used for imaging glucose in zebrafish. Our research provides a new strategy for designing efficient boronic acid glucose probes and powerful new tools for the evaluation of glucose-related diseases.

15.
Int J Biol Macromol ; 242(Pt 2): 124635, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37121414

RESUMEN

Genistein is an isoflavone with chemopreventive and therapeutic effects on various types of cancers. Apparently, in contrast to the advantages of multi-target therapy, the poor water solubility of this molecule is a major obstacle to its clinical application. In this work, zein/chicory polysaccharide nanoparticles (G-zein-P NPs) were prepared by pH-induced antisolvent precipitation method for the encapsulation of genistein. Firstly, an acidic polysaccharide (CIP70-2) with a molecular weight of 66.7 kDa was identified from the roots of chicory (Cichorium intybus). This natural macromolecule was identified as a plant pectin, for which the structure included RG-I (rhamnogalacturonan I) and HG (homogalacturonan) regions. Using this polysaccharide, G-zein-P NPs were prepared, in which the water solubility of genistein was improved by encapsulation. The encapsulation efficiency and loading efficiency of genistein by composite nanoparticles reached 99.0 % and 6.96 %, respectively. In vitro tumor inhibition experiments showed that the inhibitory effect of G-zein-P NPs on HepG2 cells was twice that of unencapsulated genistein. Moreover, the significant inhibition of tumor development and metastasis by G-zein-P NPs was observed in zebrafish xenograft models. The results suggested that zein/chicory polysaccharide nanoparticles may be a promising delivery carrier for genistein application in cancer prevention and therapy.


Asunto(s)
Cichorium intybus , Nanopartículas , Neoplasias , Zeína , Animales , Humanos , Genisteína/farmacología , Cichorium intybus/química , Zeína/química , Pez Cebra , Polisacáridos/farmacología , Agua , Nanopartículas/química , Tamaño de la Partícula , Neoplasias/tratamiento farmacológico
16.
Chem Sci ; 14(12): 3302-3310, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36970103

RESUMEN

We report here a concise and divergent enantioselective total synthesis of the revised structures of marine anti-cancer sesquiterpene hydroquinone meroterpenoids (+)-dysiherbols A-E (6-10) using dimethyl predysiherbol 14 as a key common intermediate. Two different improved syntheses of dimethyl predysiherbol 14 were elaborated, one starting from Wieland-Miescher ketone derivative 21, which is regio- and diastereoselectively α-benzylated prior to establishing the 6/6/5/6-fused tetracyclic core structure through intramolecular Heck reaction. The second approach exploits an enantioselective 1,4-addition and a Au-catalyzed double cyclization to build-up the core ring system. (+)-Dysiherbol A (6) was prepared from dimethyl predysiherbol 14via direct cyclization, while (+)-dysiherbol E (10) was synthesized through allylic oxidation and subsequent cyclization of 14. Epoxidation of 14 afforded allylic alcohol 45 or unexpectedly rearranged homoallylic alcohol 44. By inverting the configuration of the hydroxy groups, exploiting a reversible 1,2-methyl shift and selectively trapping one of the intermediate carbenium ions through oxy-cyclization, we succeeded to complete the total synthesis of (+)-dysiherbols B-D (7-9). The total synthesis of (+)-dysiherbols A-E (6-10) was accomplished in a divergent manner starting from dimethyl predysiherbol 14, which led to the revision of their originally proposed structures.

17.
Molecules ; 28(3)2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36770683

RESUMEN

α-Mangostin, a natural xanthone, was found to have anticancer effects, but these effects are not sufficient to be effective. To increase anticancer potential and selectivity, a triphenylphosphonium cation moiety (TPP) was introduced to α-mangostin to specifically target cancer cell mitochondria. Compared to the parent compound, the cytotoxicity of the synthesized compound 1b increased by one order of magnitude. Mechanistic analysis revealed that the anti-tumor effects were involved in the mitochondrial apoptotic pathway by prompting apoptosis and arresting the cell cycle at the G0/G1 phase, increasing the production of reactive oxygen species (ROS), and reducing mitochondrial membrane potential (Δψm). More notably, the antitumor activity of compound 1b was further confirmed by zebrafish models, which remarkably inhibited cancer cell proliferation and migration, as well as zebrafish angiogenesis. Taken together, our results for the first time indicated that TPP-linked 1b could lead to the development of new mitochondrion-targeting antitumor agents.


Asunto(s)
Antineoplásicos , Xantonas , Animales , Pez Cebra/metabolismo , Apoptosis , Proliferación Celular , Xantonas/farmacología , Xantonas/metabolismo , Mitocondrias/metabolismo , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo
18.
Int J Biol Macromol ; 232: 123261, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36649870

RESUMEN

The combination of selenium and polysaccharides is one of the significant ways to ameliorate the anti-cancer effects of polysaccharides. PLP50-1, a homogeneous polysaccharide purified from the aqueous extract of Paeonia lactiflora, had a molecular weight of 1.52 × 104 Da and consisted of α-D-Glcp-(1→, →4)-α-D-Glcp-(1→, →6)-α-D-Glcp-(1→, →4,6)-α-D-Glcp-(1→, and →6)-ß-D-Fruf-(2→. PLP50-1 showed weak anti-tumor effects against A549 cells. To ameliorate the activity of PLP50-1, the complex nanoparticles combining P. lactiflora polysaccharide with selenium were constructed successfully. Structural properties of the polysaccharide-based selenium nanoparticles (PLP-SeNPs) were clarified using various means. The results displayed that a kind of monodisperse spherical nanoparticles containing high selenium content (39.1 %) with controllable size was constructed and showed satisfactory stability. The cellular anti-tumor assay indicated that PLP-SeNPs had stronger antiproliferative activity against A549 cells than PLP50-1. Additionally, the zebrafish experiments displayed that PLP-SeNPs inhibited the proliferation and migration of A549 cells significantly and blocked the angiogenesis.


Asunto(s)
Nanopartículas , Paeonia , Selenio , Animales , Selenio/química , Pez Cebra , Línea Celular Tumoral , Polisacáridos/farmacología , Polisacáridos/química , Nanopartículas/química
19.
Appl Environ Microbiol ; 89(1): e0154722, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36519886

RESUMEN

Antibiotic resistance mediated by bacterial enzyme inactivation plays a crucial role in the degradation of antibiotics in the environment. Chloramphenicol (CAP) resistance by enzymatic inactivation comprises nitro reduction, amide bond hydrolysis, and acetylation modification. However, the molecular mechanism of enzymatic oxidation of CAP remains unknown. Here, a novel oxidase gene, cmO, was identified and confirmed biochemically. The encoded CmO oxidase could catalyze the oxidation at the C-1' and C-3' positions of CAP and thiamphenicol (TAP) in Sphingobium sp. strain CAP-1. CmO is highly conserved in members of the family Sphingomonadaceae and shares the highest amino acid similarity of 41.05% with the biochemically identified glucose methanol choline (GMC) oxidoreductases. Molecular docking and site-directed mutagenesis analyses demonstrated that CAP was anchored inside the protein pocket of CmO with the hydrogen bonding of key residues glycine (G) 99, asparagine (N) 518, methionine (M) 474, and tyrosine (Y) 380. CAP sensitivity tests demonstrated that the acetyltransferase and CmO could enable a higher level of resistance to CAP than the amide bond-hydrolyzing esterase and nitroreductase. This study provides a better theoretical basis and a novel diagnostic gene for understanding and assessing the fate and resistance risk of CAP and TAP in the environment. IMPORTANCE Rising levels of antibiotic resistance are undermining ecological and human health as a result of the indiscriminate usage of antibiotics. Various resistance mechanisms have been characterized-for example, genes encoding proteins that degrade antibiotics-and yet, this requires further exploration. In this study, we report a novel gene encoding an oxidase involved in the inactivation of typical amphenicol antibiotics (chloramphenicol and thiamphenicol), and the molecular mechanism is elucidated. The findings provide novel data with which to understand the capabilities of bacteria to tackle antibiotic stress, as well as the complex function of enzymes in the contexts of antibiotic resistance development and antibiotic removal. The reported gene can be further employed as an indicator to monitor amphenicol's fate in the environment, thus benefiting risk assessment in this era of antibiotic resistance.


Asunto(s)
Antibacterianos , Cloranfenicol , Farmacorresistencia Bacteriana , Oxidorreductasas , Sphingomonadaceae , Tianfenicol , Humanos , Antibacterianos/metabolismo , Antibacterianos/farmacología , Cloranfenicol/metabolismo , Cloranfenicol/farmacología , Simulación del Acoplamiento Molecular , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Sphingomonadaceae/genética , Sphingomonadaceae/metabolismo , Tianfenicol/metabolismo , Tianfenicol/farmacología , Farmacorresistencia Bacteriana/genética
20.
Int J Biol Macromol ; 224: 1303-1312, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36306902

RESUMEN

Photothermal therapy is a novel strategy for cancer treatment, which can kill tumor cells by converting light energy into heat energy through irradiating photothermal conversion materials with laser. As a common photothermal agent, gold nanorods (GNRs) have characteristics of high conversion efficiency and long circulation time in vivo. However, improving stability and reducing toxicity of GNRs remain a significant challenge. In this research, a simple and novel strategy for the synthesis of modified GNRs was proposed. The polysaccharide CL90 was obtained from lemon, which was modified to afford thiolated lemon polysaccharide (SH-CL90). SH-CL90 was used to prepare stable GNRs and give the composite GNRs-SH-CL90, which was found to have good stability in PBS solution and possess high photothermal conversion effects and photothermal stability. The biological experiments revealed that GNRs-SH-CL90 inhibited tumor cell proliferation under near-infrared light irradiation and could induce apoptosis significantly. Furthermore, in vivo experiments supported that GNRs-SH-CL90 could inhibit the proliferation and migration of tumor cells. All the experiments demonstrated that GNRs-SH-CL90 might be promising in the field of cancer treatment.


Asunto(s)
Oro , Nanotubos , Oro/farmacología , Terapia Fototérmica , Fototerapia , Polisacáridos , Línea Celular Tumoral
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