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1.
Fitoterapia ; 165: 105418, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36587747

RESUMEN

Fourteen new sulphur-containing amides, glycocramides A-N (1-14), as well as nine known analogues (15-23) were isolated and characterized from Glycosmis craibii Tanaka. The chemical structures of new sulphur-containing amides 1-14 were ambiguously elucidated by extensive spectroscopic methods, while the known compounds 15-23 were identified by the comparison of their experimental spectral data with those described data in the literatures. The antiproliferative effects of all isolated sulphur-containing amides were evaluated in vitro. As a result, part of sulphur-containing amides showed remarkable inhibitory effects against MGC-803 cell line with IC50 values ranging from 13.12 ± 0.10 to 20.03 ± 0.13 µM. These research results suggest that the sulphur-containing amides are potentially to be developed as a new natural anti-tumor drugs.


Asunto(s)
Amidas , Rutaceae , Amidas/farmacología , Amidas/química , Estructura Molecular , Azufre , Extractos Vegetales/química , Rutaceae/química , Línea Celular Tumoral
2.
J Ethnopharmacol ; 295: 115393, 2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-35609755

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The morphological characteristics of Ganoderma cochlear (Blume & T. Nees) Bres were identical to G. sinsense J.D. Zhao, L.W. Hsu & X.Q. Zhang, however, with the fungus stipe lying in the back of the pileus. Fruiting bodies and spores of G. cochear have been traditionally used for smoothing, sleeping improvement, memory impairment, anti-aging, and prolonging life. Alzheimer's disease (AD) is a chromic progressive neurodegenerative disorder associated with loss of memory and cognition. Hallmarks of AD include aging, amyloid-ß plaques, neurofibrillary tangles, neuron loss, neuronal degeneration, network disruption, cognitive dysfunction, inflammation and oxidation stress. In this study, norlanostanoids from G. cochear are identified as potential neurotrophic chemists related to the memory impairment usage to slow down pathogenetic process and restore neural circuits for AD. AIM OF STUDY: Chemical and biological investigations in this study uncovered the potential constituents related to the traditional usage of G. cochlear. MATERIALS AND METHODS: The extract of the mushrooms was purified using various column chromatography techniques and high-performance liquid chromatography (HPLC). The structures of the isolates were elucidated by combination of spectral, and single crystal X-ray diffraction analysis. The neurotrophic activity was evaluated by the differentiation state of PC12 cells, and the dose-dependent and time-dependant expression of growth-associated protein (GAP-43) was analyzed by western blotting. RESULTS: Ganorbifates J-T (1-11), eleven previously undescribed triterpenoids together with five known trinorlanostanoids (12-16) were isolated from the fruiting bodies of G. Cochlear. Among them, ganorbifates N-O (5-6) had a demethylation at C-28 compared to the classic skeleton of 3,4-seco-25,26,27-trinorlanostanoids to form a new group of 3,4-seco-25,26,27,28-tetranorlanostanoids. Based on this, a novel skeleton of ganorbifate M (4) was further established by the arrangement of C-29 from C-4 to C-7. A plausible biosynthetic pathway of compounds 4-6 was proposed. Eight of the sixteen isolates showed neurotrophic activity with the concentration of 10 µM. Furthermore, compound 15 exhibited a dose-dependent neurogenic activity, and also strengthened the expression of the growth-associated protein (GAP-43) in NGF-induced PC-12 cells, whereas 11 showed an inhibitory effect at higher concentration. CONCLUSION: These results demonstrated that 3,4-seco-norlanostanoids had reliable potential in promoting the outgrowth of PC-12 cells and could be used in the prevention and treatment of Alzheimer's disease, which is consist with the beneficial effects of G. Cochlear.


Asunto(s)
Enfermedad de Alzheimer , Ganoderma , Triterpenos , Animales , Proteína GAP-43 , Ganoderma/química , Estructura Molecular , Células PC12 , Ratas
3.
Nat Prod Res ; 36(1): 379-384, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32619098

RESUMEN

A phytochemical investigation on the stems of Glycosmis puberula var. craibii led to the isolation of a new indole alkaloid (named glycosmiscrol A, 1), together with four known compounds (2-5). The new structure was elucidated by detailed analysis of comprehensive spectroscopic methods. All isolated compounds were evaluated for their antiproliferative activities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1-5 showed significant antiproliferative effects with IC50 values ranging from 0.16 to 8.58 µM.


Asunto(s)
Antineoplásicos Fitogénicos , Rutaceae , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Humanos , Alcaloides Indólicos/farmacología , Estructura Molecular , Tallos de la Planta
4.
Nano Lett ; 21(14): 6202-6210, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34259530

RESUMEN

Life is recognized as a sophisticated self-assembling material system. Cancer involves the overexpression and improper self-assembly of proteins, such as cytoskeleton protein vimentin, an emerging target related to tumor metastasis. Herein, we design a binding-induced fibrillogenesis (BIF) peptide that in situ forms fibrous networks, blocking the improper self-assembly of vimentin against cancer. The BIF peptide can bind to vimentin and subsequently perform fibrillogenesis to form fibers on vimentin. The resultant peptide fibrous network blocks vimentin skeletonization and inhibits the migration and invasion of tumor cells. In mouse models of tumor metastasis, the volume of tumor and the number of lung metastases are markedly decreased. Moreover, the efficacy of BIF peptide (5 mg/kg) is much higher than small molecular antimetastasis drug withaferin A (5 mg/kg) as a standard, indicating that the BIF peptide shows advantages over small molecular inhibitors in blocking the intracellular protein self-assembly.


Asunto(s)
Neoplasias de la Mama , Animales , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Movimiento Celular , Femenino , Humanos , Ratones , Péptidos , Vimentina/genética
5.
Biomaterials ; 275: 120900, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34051670

RESUMEN

Different from chemical (small molecular inhibitor) and biological (monoclonal antibody) drugs, herein, based on angiogenesis-related neuropilin-1 (NRP-1), we develop a biomimetic superstructure drug, i.e. an antibody-like peptidic network (ALPN) to achieve the high-efficient treatment of choroidal neovascularization (CNV). The ALPN in nanoparticulated formulation (ALPN-NPS) can bind NRP-1 through targeting unit and form fibrous peptidic networks trapping NRP-1 on the surface of endothelial cells (ECs), leading to anti-angiogenesis. The ALPN shows high-efficacy against angiogenesis in CNV rat model ascribed to the superstructure-enhanced binding and blockage of NRP-1. The very low dose of ALPN (0.263 µg/Kg) exhibits similar anti-angiogenesis effect comparing with monoclonal antibody bevacizumab (23.5 µg/Kg), which shows potential advantages over traditional monoclonal antibodies.


Asunto(s)
Neovascularización Coroidal , Células Endoteliales , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Neovascularización Coroidal/tratamiento farmacológico , Neuropilina-1 , Péptidos/uso terapéutico , Ratas
6.
Sci Adv ; 6(22): eaaz4107, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32766439

RESUMEN

Platelets play a critical role in the regulation of coagulation, one of the essential processes in life, attracting great attention. However, mimicking platelets for in vivo artificial coagulation is still a great challenge due to the complexity of the process. Here, we design platelet-like nanoparticles (pNPs) based on self-assembled peptides that initiate coagulation and form clots in blood vessels. The pNPs first bind specifically to a membrane glycoprotein (i.e., CD105) overexpressed on angiogenetic endothelial cells in the tumor site and simultaneously transform into activated platelet-like nanofibers (apNFs) through ligand-receptor interactions. Next, the apNFs expose more binding sites and recruit and activate additional pNPs, forming artificial clots in both phantom and animal models. The pNPs are proven to be safe in mice without systemic coagulation. The self-assembling peptides mimic platelets and achieve artificial coagulation in vivo, thus providing a promising therapeutic strategy for tumors.


Asunto(s)
Plaquetas , Trombosis , Animales , Biomimética , Coagulación Sanguínea , Plaquetas/metabolismo , Células Endoteliales , Ratones , Péptidos/metabolismo , Péptidos/farmacología , Trombosis/metabolismo
7.
Sci Adv ; 6(19): eaaz4767, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32494712

RESUMEN

Using broad-spectrum antibiotics for microbial infection may cause flora disequilibrium, drug-resistance, etc., seriously threatening human health. Here, we design a human defensin-6 mimic peptide (HDMP) that inhibits bacterial invasion in vivo through mimicking the mechanisms of human defensin-6 with high efficiency and precision. The HDMP with ligand and self-assembling peptide sequence recognizes bacteria through ligand-receptor interactions and subsequently traps bacteria by an in situ adaptive self-assembly process and resulting nanofibrous networks; these trapped bacteria are unable to invade host cells. In four animal infection models, the infection rate was markedly decreased. Notably, administration of HDMP (5 mg/kg) nanoparticles increased the survival rate of mice with methicillin-resistant S. aureus bacteremia by as much as 100%, even more than that of vancomycin treatment (5 mg/kg, 83.3%)-treated group, the golden standard of antibiotics. This biomimetic peptide shows great potential as a precise and highly efficient antimicrobial agent.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Animales , Antibacterianos/farmacología , Bacterias , Biomimética , Defensinas/farmacología , Humanos , Ligandos , Ratones , Vancomicina/farmacología
8.
ACS Nano ; 14(6): 7170-7180, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32407069

RESUMEN

Cancer therapeutic strategies based on angiogenesis attract great attention from fundamental and clinical research. Blocking oxygen and nutrition supply to tumor cells could inhibit the growth of tumors based on occlusion of blood vessels in the tumor. Herein, we report a dual-responsive peptide-based nanoparticle, mimicking the laminin fibrillogenesis specifically and highly efficiently in tumor vessels, resulting in the blockage of tumor vessels and the growth inhibition of tumors. The laminin mimic peptide (LMMP) is designed with a fibrillation sequence, a pH-responsive sequence, and a targeting sequence. The LMMP in nanoformulations is delivered to blood vessels in the tumors, where the microenvironment (pH and microthrombus) enable LMMP to process laminin fibrillogenesis, constructing fibrous networks. The laminin-like fibrous networks capture red blood cells etc., forming occlusion specifically in the tumor blood vessels to inhibit the growth of the tumor.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Laminina , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Péptidos , Microambiente Tumoral
9.
RSC Adv ; 11(1): 525-536, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-35423046

RESUMEN

Two chromophoric congeners derived from indenoquinoxaline and oxadiazole are designed, synthesized and characterized for their multi-photon properties in the femtosecond time domain. These two model structures are experimentally found to exhibit strong and widely distributed two- and three-photon activities within the spectral range of 680-1500 nm and the larger congener manifests maximum two- and three-photon absorption cross-section values of 2120 GM (at 750 nm) and ∼85 × 10-80 cm6 s2 (at 1280 nm), respectively. Both two- and three-photon absorption-based optical power-limiting performance of a representative model compound are also evaluated and demonstrated.

10.
ChemSusChem ; 12(15): 3654-3665, 2019 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-31168948

RESUMEN

A series of Y-shaped sensitizers incorporating quinoxaline or quinoxalinoid moieties were prepared and applied in dye-sensitized solar cells (DSSCs). By the introduction of quinoxalinoid functionalities, the absorption extinction coefficients could be enhanced. The molecular structures were modified by introducing an extra acceptor group (A) between a donor (D) and a π-bridge (D-A-π-A) and also by incorporating electron-donating substituents at various positions of the quinoxalinoid moiety. Some of the dyes and mixtures thereof were found to exhibit good light-harvesting efficiencies under both sunlight and indoor light, with efficiencies up to 7.92 % under one sun (AM 1.5G). When operated under indoor light, the efficiency could be boosted to 27.76, 28.74, and 30.45 % under 600, 1000, 2500 lux illumination, respectively. The best performance could be ascribed partly to an improved dye coverage on the TiO2 surface.

11.
ACS Appl Mater Interfaces ; 10(40): 34272-34282, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30222306

RESUMEN

As a promising cathode material of sodium-ion battery, P2-type Na2/3Ni1/3Mn2/3O2 (NNMO) possesses a theoretically high capacity and working voltage to realize high energy storage density. However, it still suffers from poor cycling stability mainly incurred by the undesirable P2-O2 phase transition. Herein, the electrochemically active Fe3+ ions are introduced into the lattice of NNMO, forming Na2/3Ni1/3Mn2/3- xFe xO2 ( x = 0, 1/24, 1/12, 1/8, 1/6) to effectively stabilize the P2-type crystalline structure. In such Fe-substituted materials, both Ni2+/Ni4+ and Fe3+/Fe4+ couples take part in the redox reactions, and the P2-O2 phase transition is well restrained during cycling, as verified by ex situ X-ray diffraction. As a result, the optimized Na2/3Ni1/3Mn7/12Fe1/12O2 (1/12-NNMF) has a long-term cycling stability with the fading rate of 0.05% per cycle over 300 cycles at 5 C. Furthermore, the 1/12-NNMF delivers excellent rate capabilities (65 mA h g-1 at 25 C) and superior low-temperature performance (the capacity retention of 94% at -25 °C after 80 cycles) owing to the enhanced Na diffusion upon Fe doping, which is deduced by the studies of electrode kinetics. More significantly, the 1/12-NNMF also displays remarkable sodium-ion full-cell properties when merged with an LS-Sb@G anode, thus implying the possibility of their practical application.

12.
Zool Res ; 37(5): 297-300, 2016 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-27686789

RESUMEN

In September and October 2015, a new species of the family Nemacheilidae, Triplophysa tianxingensis sp. nov., was discovered from underground water in Qiubei County, Yunnan Province, China. It can be distinguished from all other troglobiotic Triplophysa species occurring in Yunnan by the following combination of characters: eyes small, a little degenerated; barbels longer; ventral profiles greatly convex; pectoral fin short, attaining a third of the distance from the pectoral-fin base to pelvic fin base; body with many brown blotches; caudal peduncle with fin fold; caudal fin shallowly forked, and free posterior chamber of swim bladder cylindrical.


Asunto(s)
Cuevas , Cipriniformes/clasificación , Animales , China , Cipriniformes/anatomía & histología , Ecosistema , Terminología como Asunto
13.
Zhong Yao Cai ; 39(5): 1075-8, 2016 May.
Artículo en Chino | MEDLINE | ID: mdl-30133192

RESUMEN

Objective: To investigate the specific biotransformation product of ginsenoside Rb1 of Panax notoginseng saponins( PNS) by an individual plant endophyte. Methods: The endophytes of an invasive plant were selected as the screening targets of active conversion strains. The chromatography and high performance liquid chromatography were used to detemine the metabolite. Results: Totally, an active strain of conversion of ginsenoside Rb1 were achieved. The strain can specifically convert ginsenoside Rb1 of PNS to ginsenoside Rd and rare saponin ginsenoside C-K,with the conversion rate of 11. 62% of ginsenoside C-K by fermentation for 12 d. Conclusion: This transformation can obviously increase the content of minor ginsenoside C-K in PNS,and it is expected to be a new way to obtain the active saponin ginsenoside C-K in quantity.


Asunto(s)
Panax notoginseng , Biotransformación , Cromatografía Líquida de Alta Presión , Endófitos , Ginsenósidos , Saponinas
14.
Z Naturforsch C J Biosci ; 70(3-4): 93-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26023990

RESUMEN

A novel C25 sterol peroxide, phomasterol A (1), together with two known compounds (2-3), was isolated from the endophytic fungus Phoma sp. EA-122. The structure of phomasterol A (1) was elucidated by MS, 1D, and 2D NMR data analyses. Phomasterol A (1) was evaluated for its inhibitory activities against protein-tyrosine phosphatases MEG2 and PTP1Bc, showing moderate activities with identical IC50 values of 25 µM.


Asunto(s)
Ascomicetos/química , Peróxidos/química , Esteroles/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Peróxidos/aislamiento & purificación , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Proteínas Tirosina Fosfatasas no Receptoras/antagonistas & inhibidores , Esteroles/aislamiento & purificación
15.
Nat Prod Res ; 29(21): 1985-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25738519

RESUMEN

A new linear triterpene (1), and a new sesquiterpene (2), together with a known compound methyl indole-3-carboxylate (3) were isolated from the crude extract of Antrodiella albocinnamomea. The structures of the new compounds 1-2 were determined by comprehensive spectroscopic analysis. Compound 1 exhibited significant inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) with IC50 value of 1.0 µg/mL.


Asunto(s)
Basidiomycota/química , Inhibidores Enzimáticos/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Sesquiterpenos/química , Triterpenos/química , Inhibidores Enzimáticos/aislamiento & purificación , Concentración 50 Inhibidora , Estructura Molecular , Sesquiterpenos/aislamiento & purificación , Triterpenos/aislamiento & purificación
16.
Fitoterapia ; 102: 61-6, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25704368

RESUMEN

Five new triquinane-type sesquiterpenes, antrodins A-E (1-5) and a new gymnomitrane sesquiterpene, antrodin F (6), together with three known compounds 7-9 were isolated from fermentation of Antrodiella albocinnamomea. Their structures were elucidated through extensive spectroscopic methods including 2D NMR and HRMS analyses. The absolute configurations of 1 and 6 were determined using single-crystal X-ray diffraction analyses. The isolated compounds were investigated for their cytotoxicities against five human cancer cell lines.


Asunto(s)
Basidiomycota/química , Sesquiterpenos/química , Línea Celular Tumoral , Fermentación , Humanos , Estructura Molecular , Sesquiterpenos/aislamiento & purificación
17.
J Antibiot (Tokyo) ; 68(1): 23-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24961709

RESUMEN

Two new cytochalsians, multirostratin A (1) and 20-oxo-deoxaphomin (2), together with five known analogues (3-7), were obtained from the endophytic fungus Phoma multirostrata EA-12. The structures of 1 and 2 were elucidated by MS and 1D- and 2D-NMR spectroscopic data analyses, as well as by comparison of data with those of analogues reported in the literature. Compounds 1 and 2 showed moderate cytotoxicity against five tumor cell lines (HL-60, A-549, SMMC-7721, MCF-7 and SW-480).


Asunto(s)
Antineoplásicos/farmacología , Ascomicetos/metabolismo , Citocalasinas/farmacología , Neoplasias/tratamiento farmacológico , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Línea Celular Tumoral , Citocalasinas/química , Citocalasinas/aislamiento & purificación , Humanos , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Neoplasias/patología
18.
Nat Prod Bioprospect ; 4(4): 207-11, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25089238

RESUMEN

Three new humulane-type sesquiterpenes, antrodols A-C (1-3), were isolated from cultures of the fungus Antrodiella albocinnamomea. Their structures were elucidated on the basis of extensive spectroscopic analysis. Antrodols A-C (1-3) are first examples of humulane-type sesquiterpenes isolated from cultures of higher fungi, and antrodol A (1) was the first report of humulane-type sesquiterpene with a methyl rearranged at C-3. All compounds were evaluated in the enzyme inhibition assay against two protein-tyrosine phosphatases (PTPs): MEG2 and PTP1Bc.

19.
Steroids ; 87: 21-5, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24880121

RESUMEN

Three novel degraded steroids, named albocisterols A-C (1-3), have been isolated from cultures of Antrodiella albocinnamomea. Their structures were defined by comprehensive spectroscopic analysis and single crystal X-ray crystallography. The mixture of compounds 2 and 3 exhibited significant inhibitory activities against protein tyrosine phosphatase 1B (PTP1B).


Asunto(s)
Técnicas de Cultivo , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Polyporales/metabolismo , Esteroides/metabolismo , Esteroides/farmacología , Inhibidores Enzimáticos/química , Humanos , Polyporales/crecimiento & desarrollo , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Esteroides/química
20.
J Asian Nat Prod Res ; 16(5): 465-70, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24717139

RESUMEN

Two new chlamydosporol derivatives, fusarilactone A (1) and fusarilactone B (2), together with nine known compounds (3-11), have been isolated from the crude extract of endophytic fungus Fusarium sp. #001. The structures of new compounds 1 and 2 were elucidated on the basis of extensive spectroscopic methods. Compound 1 showed mild cytotoxicities against three tumor cell lines (SMMC-7721, A-549, and MCF-7).


Asunto(s)
Antineoplásicos/aislamiento & purificación , Fusarium/química , Pironas/aislamiento & purificación , Antineoplásicos/química , Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Estructura Molecular , Pironas/química , Pironas/farmacología
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