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1.
J Control Release ; 368: 498-517, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38428529

RESUMEN

The treatment of advanced hepatocellular carcinoma (HCC) is limited, and immunotherapy is the current research focus of multi-disciplinary collaborative comprehensive treatment of HCC. Herein, we constructed a bio-responsive Au-miR-183 inhibitor (Au@miR-183i) delivery system targeting liver cancer stem cells (LCSCs), and adopted the strategy of combining αPD-L1 immunotherapy. The multifunctional Au@miR-183i nanocomplexes (NCs), which self-assemble based on the tumor microenvironment, consume NADPH and H2O2, leading to redox homeostasis disturbance, ROS accumulation, regulation of the LCSC niche, and induction of stemness regression. Moreover, self-assembled Au@miR-183i NCs specifically target the delivery of miR-183i to LCSCs, triggering the immunogenic cell death (ICD) effect, promoting the maturation of dendritic cells, inducing infiltration of CD8+ T cells, and facilitating the transformation of 'cold' tumors into 'hot' tumors. More importantly, consistent with the results in vitro, Au@miR-183i NCs demonstrated effective tumor targeting and strong ICD induction in vivo, assisted in enhancing αPD-L1 immunotherapy, and activated a robust systemic anti-tumor immune response in tumor-bearing mouse models. Overall, we provide a simple and universal therapeutic strategy by constructing a multifunctional bio-responsive Au@miR-183i NCs delivery system with LCSC targeting capability. Furthermore, nanocomplex-based ICD inducers have great promise in enhancing anti-tumor immunity and the PD-1/PD-L1 blocking efficacy in HCC, which provides a theoretical basis for effectively eliminating LCSCs and achieving a high-efficiency synergistic treatment strategy for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Animales , Ratones , Carcinoma Hepatocelular/terapia , Peróxido de Hidrógeno , Muerte Celular Inmunogénica , Neoplasias Hepáticas/terapia , Inmunoterapia , Microambiente Tumoral , Línea Celular Tumoral
2.
Front Pharmacol ; 14: 1276038, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38116081

RESUMEN

Salvia miltiorrhiz, commonly known as "Danshen" in Chinese medicine, has longstanding history of application in cardiovascular and cerebrovascular diseases. Renowned for its diverse therapeutic properties, including promoting blood circulation, removing blood stasis, calming the mind, tonifying the blood, and benefiting the "Qi", recent studies have revealed its significant positive effects on bone metabolism. This potential has garnered attention for its promising role in treating musculoskeletal disorders. Consequently, there is a high anticipation for a comprehensive review of the potential of Salvia miltiorrhiza in the treatment of various musculoskeletal diseases, effectively introducing an established traditional Chinese medicine into a burgeoning field. AIM OF THE REVIEW: Musculoskeletal diseases (MSDs) present significant challenges to healthcare systems worldwide. Previous studies have demonstrated the high efficacy and prospects of Salvia miltiorrhiza and its active ingredients for treatment of MSDs. This review aims to illuminate the newfound applications of Salvia miltiorrhiza and its active ingredients in the treatment of various MSDs, effectively bridging the gap between an established medicine and an emerging field. METHODS: In this review, previous studies related to Salvia miltiorrhiza and its active ingredients on the treatment of MSD were collected, the specific active ingredients of Salvia miltiorrhiza were summarized, the effects of Salvia miltiorrhiza and its active ingredients for the treatment of MSDs, as well as their potential molecular mechanisms were reviewed and discussed. RESULTS: Based on previous publications, Salvianolic acid A, salvianolic acid B, tanshinone IIA are the representative active ingredients of Salvia miltiorrhiza. Their application has shown significant beneficial outcomes in osteoporosis, fractures, and arthritis. Salvia miltiorrhiza and its active ingredients protect against MSDs by regulating different signaling pathways, including ROS, Wnt, MAPK, and NF-κB signaling. CONCLUSION: Salvia miltiorrhiza and its active ingredients demonstrate promising potential for bone diseases and have been explored across a wide variety of MSDs. Further exploration of Salvia miltiorrhiza's pharmacological applications in MSDs holds great promise for advancing therapeutic interventions and improving the lives of patients suffering from these diseases.

3.
Inorg Chem ; 62(35): 14152-14157, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37552507

RESUMEN

Chirality is a fundamental property of nature, and thus, building novel chiral molecules plays a crucial role in multidisciplinary fields. Herein, we have developed a straightforward approach to effectively incorporate all four types of point, axial, planar, and helical chiralities into a single molecule for the first time. The resultant "point-line-plane-helix" binuclear Pt(II) complexes exhibit multiple chiralities, including not only point and axial chiralities from the bridging ligands but also planar and helical chiralities from metal coordination. The intramolecular π-π and Pt-Pt interactions will restrict intramolecular rotations, thereby stabilizing the metal-induced planar and helical chiralities. Furthermore, enantiopure (R,R,R,Rp,M) or (S,S,S,Sp,P) molecules could be obtained by chirality self-sorting without the use of chiral high-performance liquid chromatography. Their single-crystal, circular dichroism, and circularly polarized luminescence properties are comprehensively investigated, providing unequivocal insights into the design of multiple-chirality materials for related applications.

4.
J Orthop Translat ; 40: 37-48, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37304218

RESUMEN

Background: Osteopenia and fragile fractures are diabetes-associated complications. Many hypoglycemic drugs have effects on bone metabolism. Metformin, as is a prescribed medication for type 2 diabetes mellitus (T2DM), had been reported to have osteoprotective effects beyond its hypoglycemic effect, however the potential mechanism behind these effects remains unclear. In this study, we aimed to investigate the comprehensive effects of metformin on bone metabolism in T2DM rat model and elucidate the potential mechanism. Methods: Goto-Kakizaki spontaneous T2DM rats with significant hyperglycemia were treated with/without metformin for 20 weeks. Glucose tolerance was tested and all rats were weighed every two weeks. The osteoprotective effects of metformin in diabetic rats were determined by quantifying serum bone biomarkers, µ-CT imaging, histological staining, bone histomorphometry, and biomechanical properties analyses. Potential targets of metformin in the treatment of T2DM and osteoporosis were predicted using network pharmacology. The effects of metformin on mesenchymal stem cells (C3H10) cultured in high glucose medium were evaluated by CCK-8 assay, alkaline phosphatase (ALP) staining, qPCR and western blotting. Results: This study demonstrated that metformin significantly attenuated osteopenia, decreased serum glucose and glycated serum protein (GSP) levels, improved bone microarchitecture, and biomechanical properties in GK rats with T2DM. Metformin significantly increased biomarkers of bone formation, and significantly decreased muscle ubiquitin C (Ubc) expression. Network pharmacology analysis found that signal transducer and activator of transcription1 (STAT1) would be a potential target of metformin for regulating bone metabolism. Metformin increased C3H10 â€‹cell viability in vitro, alleviated ALP inhibition caused by hyperglycemia, increased the osteogenic gene expression of runt-related transcription factor 2 (RUNX2), collagen type I alpha 1 (Col1a1), osteocalcin (OCN), and ALP, while suppressing RAGE and STAT1 expression. Metformin also increased the protein expression of Osterix and decreased that of RAGE, p-JAK2, and p-STAT1. Conclusions: Our results demonstrate that metformin attenuated osteopenia and improved bone microarchitecture in GK rats with T2DM and significantly promoted stem cell osteogenic differentiation under high glucose condition. The effects of metformin on bone metabolism are closely associated with the suppression of RAGE-JAK2-STAT1 signaling axis. The translational potential of this article: Our research provides experiment evidence and potential mechanistic rationale for the use of metformin as an effective candidate for diabetes-induced osteopenia treatment.

5.
Angew Chem Int Ed Engl ; 62(21): e202302011, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36939317

RESUMEN

PtII complexes have attracted a great deal of interest due to their rich phosphorescent properties. However, these square-planar PtII complexes are far more likely to encounter the problems of lack of metal-induced chirality and emission "aggregation-caused quenching". Herein, soft-bridged binuclear PtII complexes bearing metal-induced planar chirality were synthesized and characterized. These soft bridging ligands with smaller conjugated system would help to not only improve solubility for synthesis and enantioseparation but also introduce point chirality from amino acid for highly efficient diastereoselectivity. Furthermore, the intramolecular Pt-Pt distances could be well regulated by soft bridging ligands, and consequently the phosphorescence quantum yield up to 100 % could be achieved by shortening intramolecular Pt-Pt distance for first time. These complexes can be used as emitters in highly efficient solution-processed organic light-emitting diodes.

6.
Nat Prod Res ; 37(9): 1527-1535, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35007177

RESUMEN

Five undescribed perylenequinone derivatives (PQDs) phialocephalarins H - L (1 - 5), together with two known PQDs phialocephalarins A - B (6, 7) and one known spirobisnaphthalene palmarumycin P3 (8) were isolated from the endolichenic fungus Phialocephala fortinii. Their structures were elucidated on the basis of NMR and HRESIMS data as well as electronic circular dichroism (ECD) calculations. Compounds 1, 2, 4, and 6 - 8 were evaluated for cytotoxic activities against NCI-H460, NCI-H446, PC3, and EC109 cell lines. The results showed that compounds 1, 2, 6, and 8 showed cytotoxic activities against EC109 cells with IC50 values ranging from 24.5 to 33.3 µM.


Asunto(s)
Antineoplásicos , Ascomicetos , Ascomicetos/química , Quinonas/farmacología , Antineoplásicos/química
7.
Sci Total Environ ; 855: 158888, 2023 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-36165908

RESUMEN

The union of Plant Growth-Promoting Bacteria (PGPB) and rhizosphere confers a series of functions beneficial to plant. However, the lack of an opearable in situ method limits the further understanding on the mechanism. In this study, a weak electric field was designed to regulate rhizospheric microflora in a constructed root-splitting reactor. Compared with the control, the aboveground and underground biomass of rice seedling increased by 17 % and 18 % (p < 0.05) respectively under the exist of weak electric field of 0.14 V/cm. The joint action of rhizosphere and PGPB displayed the detoxification ability in the condition of soluble petroleum hydrocarbons, where the height, stem diameter, biomass and root vigor of the plant was increased by 58 %, 32 %, 43 % and 48 % respectively than the control. The selective reproduction of endophytes and ectophytes (denitrifying, auxin-producing, hydrocarbon-degrading and electroactive bacteria) was observed under applied weak electric field, which enhanced the nitrogen utilization, cellular metabolic activity and resistance to toxic organics of plant. This was further confirmed by the up-regulated OTUs related to the hydrocarbon degradation function, tryptophan metabolism and metabolism of nicotinate and nicotinamide. Moreover, the weak electric field also enhanced the transfer ability of partial endophytes grown in the root to improve plant stress resistance. The results in this work inspired an exercisable method for in situ enrichment of PGPB in the rhizosphere to cope with food crisis and provided a new way to deal with sudden environmental events.


Asunto(s)
Contaminantes Ambientales , Contaminantes del Suelo , Contaminantes Ambientales/metabolismo , Raíces de Plantas/metabolismo , Rizosfera , Desarrollo de la Planta , Endófitos/metabolismo , Hidrocarburos/metabolismo , Bacterias/metabolismo , Plantas/metabolismo , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Microbiología del Suelo
8.
J Phys Chem Lett ; 13(25): 5838-5844, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35727022

RESUMEN

Ultralong room-temperature phosphorescence (RTP) is greatly important in a series of applications, but obtaining RTP from metal-free organic materials is still an enormous challenge due to the spin-forbidden nature of triplet excitons. Because of its electron-rich nature and easy derivatization, carbazole (Cz) is widely used to build organic RTP and thermally activated delayed fluorescence (TADF) materials. However, Liu et al. (Nat. Mater. 2021, 20, 175) recently demonstrated that the RTP of Cz is induced by charge traps of its isomeric impurity in commercial sources. Here, on the basis of the classical El-Sayed rule and the recently discovered intersystem crossing promotion principles (twisted structure and charge transfer), we designed and prepared highly pure (>99.9%) (R/S)-octahydro-binaphthyl-based bicarbazoles (BiCz) for high-performance RTP (ΦP = 23%; τp = 1.09 s). Interestingly, BiCz exhibited photoactivated TADF and RTP in isolated and aggregated states, respectively, and thus would be an efficient tool for rejuvenating Cz-based RTP.

9.
Drug Des Devel Ther ; 16: 1311-1347, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35547865

RESUMEN

Drug delivery for osteoarthritis (OA) treatment is a continuous challenge because of their poor bioavailability and rapid clearance in joints. Intra-articular (IA) drug delivery is a common strategy and its therapeutic effects depend mainly on the efficacy of the drug-delivery system used for OA therapy. Different types of IA drug-delivery systems, such as microspheres, nanoparticles, and hydrogels, have been rapidly developed over the past decade to improve their therapeutic effects. With the continuous advancement in OA mechanism research, new drugs targeting specific cell/signaling pathways in OA are rapidly evolving and effective drug delivery is critical for treating OA. In this review, recent advances in various IA drug-delivery systems for OA treatment, OA targeted strategies, and related signaling pathways in OA treatment are summarized and analyzed based on current publications.


Asunto(s)
Nanopartículas , Osteoartritis de la Rodilla , Sistemas de Liberación de Medicamentos , Humanos , Hidrogeles , Inyecciones Intraarticulares , Osteoartritis de la Rodilla/tratamiento farmacológico
10.
Antimicrob Agents Chemother ; 66(3): e0212621, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35041505

RESUMEN

Palmarumycin P3 (PP3) reduces fluconazole-induced MDR1 transcription to reverse azole resistance in clinical Candida strains. Here, we demonstrated that PP3 restores the susceptibility to several antifungal drugs for Candida albicans strains with gain-of-function mutations in the transcription factor Mrr1. In addition, PP3 inhibits the efflux of Mdr1 substrates by C. albicans strains harboring hyperactive MRR1 alleles. Molecular docking revealed that PP3 is a potential Mdr1 blocker that binds to the substrate binding pocket of Mdr1.


Asunto(s)
Azoles , Regulación Fúngica de la Expresión Génica , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antifúngicos/metabolismo , Antifúngicos/farmacología , Azoles/metabolismo , Azoles/farmacología , Candida albicans/genética , Candida albicans/metabolismo , Farmacorresistencia Fúngica/genética , Fluconazol/metabolismo , Fluconazol/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Simulación del Acoplamiento Molecular
11.
Phytochemistry ; 196: 113079, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34995881

RESUMEN

Fourteen undescribed compounds, including five 2,5-diarylcyclopentenones xylariaones A1-B2, seven α-pyrone derivatives xylaripyones A-G, one γ-pyrone derivative xylaripyone H, one diketopiperazine cyclo-(L-Leu-N-ethyl-L-Glu), and two known diketopiperazines, were isolated from cultures of the endophytic fungus Xylaria sp., which was separated from Cudrania tricuspidata Bureau ex Lavallée. Their structures were determined by analysing extensive spectroscopic data (HRESIMS and NMR) and electronic circular dichroism (ECD) calculations. Furthermore, these compounds were evaluated for potential antiproliferative activity against the human tumour cell lines PC3 and A549, and the results showed that xylaripyone D exhibited moderate inhibitory activity against the proliferation of PC3 cell lines with an IC50 value of 14.75 µM. Meanwhile, xylariaone A3 and xylaripyone F displayed weak inhibitory effects on NO production in RAW 264.7 murine macrophages with IC50 values of 49.76 and 69.68 µM, respectively.


Asunto(s)
Moraceae , Xylariales , Animales , Línea Celular Tumoral , Dicetopiperazinas/química , Macrófagos , Ratones , Estructura Molecular , Moraceae/química
12.
J Am Chem Soc ; 144(5): 2233-2244, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35048693

RESUMEN

Chiral organometallic complexes have demonstrated many potential and practical applications. However, building metal-induced chirality for square-planar complexes still remains a big challenge, because their 2D planar molecular structures are usually superimposable on their mirror images. Herein, we report a straightforward and efficient way to achieve a novel kind of planar chirality by constructing 3D double-layer molecular structures. When the achiral ligand 1,3,4-oxadiazole-2-thiol (OXT) was used to bridge two square-planar complexes, a pair of racemic R/S planar-chiral binuclear Pt(II) complexes was obtained, which could be separated by chiral high-performance liquid chromatography (HPLC). Moreover, enantiopure R,R,R or S,S,S complexes could be prepared by the use of chiral (R)-/(S)-binaphthalene-derived OXT ligands in 99% diastereoselectivity without the use of chiral HPLC. The binaphthalene groups help to ensure good solubility and a smooth amorphous thin film morphology but have little effect on the photophysical properties. The resultant complexes display strong orange-red and near-infrared phosphorescence with quantum yields of up to 83.4% and can be applied as emitters in highly efficient solution-processed organic light-emitting diodes to achieve luminance, luminance efficiency, external quantum efficiency, and an asymmetry factor of up to 3.22 × 104 cd m-2, 28.7 cd A-1, 14.3%, and 2.0 × 10-3, respectively. With a comprehensive consideration of EL efficiency and the asymmetry factor, this is the best performance among Pt(II) complex based circularly polarized OLEDs. Therefore, this work provides a new and simple strategy to build planar chirality for chiroptical and circularly polarized luminescence applications.

13.
Inorg Chem ; 60(17): 13557-13566, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34409839

RESUMEN

A new series of axially chiral binuclear Pt(II) complexes with bridging ligands of binaphthalenes and octahydro-binaphthalenes and auxiliary ligands of ß-diketones were designed and prepared. These complexes, identified by spectral and electrochemical methods and single-crystal X-ray diffraction, emit an orange-red phosphorescence with a quantum yield up to 21% and 70% in solution and solid, respectively, due to the effect of steric hindrance from bridging ligands and the 2,3-position extension of chiral axis planes. They can be used as emitters in solution-processed organic light-emitting diodes to achieve luminance efficiency, asymmetry factor, and external quantum efficiency up to 5.4 cd A-1, 3.0 × 10-3, and 3.1%, respectively. Moreover, the essential relationships between their chemical structures and luminescence quantum efficiency and asymmetry factor are discussed, which affords explicit insights for designing circularly polarized luminescent materials and devices.

14.
J Hazard Mater ; 420: 126592, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34265647

RESUMEN

The soil contaminated by petroleum hydrocarbons has been a global environmental problem and its remediation is urgent. A combined phyto-microbial-electrochemical system (PMES) was constructed to repair the oil-contaminated soil in this study. During the 42-day operation time, a total petroleum hydrocarbons (TPHs) of 18.0 ± 3.0% were removed from PMES, which increased by 414% compared with the control group (CK1). The supervision of physicochemical properties of pore water in soil exhibited an enhanced microbial consumption of the total organic carbon (TOC) and N source under the applied potential with the generation of bio-current. The microbial succession indicated that the Dietzia, Georgenia and Malbranchea possibly participated in the degradation and current output in PMES. And a collaborative network of potential degrading microorganisms including unclassified norank_f__JG30-KF-CM45 (in Chloroflexi), Dietzia and Malbranchea was discovered in PMES. While the functional communities of microorganism were re-enriched with the reconstructed interactions in the system which was started with the sterilized soil (S+MEC). The superiority of TPHs degradation in S+MEC compared to P + CK2 (removing the electrochemical effect relative to CK1) revealed the key role of external potential in regulating the degradation microflora. The study provided a strategy of the potential regulated phyto-microbial interaction for the removal of TPHs.


Asunto(s)
Petróleo , Contaminantes del Suelo , Biodegradación Ambiental , Hidrocarburos , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisis
15.
J Burn Care Res ; 42(3): 555-559, 2021 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33175155

RESUMEN

Third- and fourth-degree frostbites usually result in loss of skin and tissue requiring amputation, and scarring. The 3- to 6-week waiting period is often necessary to determine the severity of the lesion. This period is also a critical time for the rescue of frostbitten tissue. This patient was a 30-year-old man who developed frostbite of his right index finger. He presented to our hospital 4 hours after injury with loss of sensation on the whole index finger and early signs of necrosis. The patient received a series of comprehensive treatments, including fasciotomy, injection of papaverine hydrochloride, baking lamp irradiation, and negative pressure treatment. At the time of discharge, he had re-epithelialization of the index finger by 21 days after injury. The conclusion of this paper is that the comprehensive treatments combined with negative pressure wound treatment has certain clinical application value for the rescue of deep frostbite tissues.


Asunto(s)
Dedos , Congelación de Extremidades/terapia , Adulto , Terapia Combinada , Fasciotomía , Humanos , Masculino , Terapia de Presión Negativa para Heridas , Papaverina/uso terapéutico , Fototerapia , Vasodilatadores/uso terapéutico
16.
Chem Asian J ; 15(20): 3370-3378, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-32893975

RESUMEN

The simpler, the better. A series of simple, neutral and ultralow-molecular-weight (MW: 140-200) hydrazide-derived supramolecular gelators have been designed and synthesized in two straightforward steps. For non-conjugated cyclohexane-derived hydrazides, their monomers can self-assemble to form gels through intermolecular hydrogen bonds and dipole-dipole interactions. Significantly, conjugated phthalhydrazide can self-aggregate into planar and circular trimers through intermolecular hydrogen bonds and then self-assemble to form gels through intermolecular π-π stacking interactions. It is interesting that these simple gelators exhibit unusual properties, such as self-healing, multi-response fluorescence, and visual and selective recognition of chiral (R)/(S)-1,1'-binaphthalene-2,2'-diamine and S2- through much different times of gel re-formation and blue-green color change, respectively. These results underline the importance of supramolecular gels and extend the scope of supramolecular gelators.

17.
ACS Appl Bio Mater ; 3(10): 7236-7242, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-35019382

RESUMEN

In the present work, a chemical reaction has been performed for supramolecular gels to achieve multiple-stimuli-responsive smart soft materials. Simple chiral binaphthalene-based receptors can condense with histidine (His) to yield a Schiff base, which would help to achieve visual chiral recognition of unprotected l/d-His through gel formation along with specific selectivity toward 20 amino acids. Through intermolecular hydrogen bonds, the resultant Schiff base molecules assemble with excess His molecules to form three-dimensional (3D) networks of metastable cross-linked nanospheres and stable nanofibers in EtOH/water and MeOH/water, respectively. Significantly, this condensation reaction exhibits unique reversible and chromatic phenomena between sol-gel phase transitions in EtOH/water, which provide a way to design chemical reaction-based multivisual-change supramolecular gels for sensing and switching applications.

18.
Chem Commun (Camb) ; 55(66): 9873-9876, 2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31364621

RESUMEN

Simple (S)- or (R)-1,1'-binaphthalene-2,2'-diol-3-carbaldehyde was found to enantioselectively self-assemble to form a gel or solution with one enantiomer of chiral amines, 1,1'-binaphthalene-2,2'-diamine, through intermolecular hydrogen bond, HH, π-π stacking, and chirality-induced interactions. The enantioselective recognition is visual and highly selective with little interference from similar organic compounds and common cations and anions.

19.
Free Radic Biol Med ; 141: 21-33, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31167117

RESUMEN

Oxidative stress is involved in the onset and progression of many human diseases. Activators of the Keap1/Nrf2/ARE pathway effectively inhibit the progression of oxidative stress-induced diseases. Herein, a small library of diterpenoids was established by means of phytochemical isolation, and chemical modification on naturally occurring molecules. The diterpenoids were subjected to a NAD(P)H: quinone reductase (QR) assay to evaluate its potential inhibition against oxidative stress. Sixteen diterpenoids were found to be novel potential activators of Nrf2-mediated defensive response. Of which, an isopimarane-type diterpenoid, sphaeropsidin A (SA), was identified as a potent activator of the Keap1/Nrf2/ARE pathway, and displayed approximately 5-folds potency than that of sulforaphane (SF). SA activated Nrf2 and its downstream cytoprotective genes through enhancing the stabilization of Nrf2 in a process involving PI3K, PKC, and PERK, as well as potentially interrupting Nrf2-Keap1 protein-protein interaction. In addition, SA conferred protection against sodium arsenite [As(III)]- and cigarette smoke extract (CSE)-induced redox imbalance and cytotoxicity in human lung epithelial cells, as wells as inhibited metronidazole (MTZ)-induced oxidative insult in Tg (krt4: NTR-hKikGR)cy17 transgenic zebrafish and lipopolysaccharide (LPS)-induced oxidative damage in wild-type AB zebrafish. These results imply that SA is a lead compound for therapeutic agent against oxidative stress-induced diseases, and diterpenoid is a good resource for discovering drug candidates and leads of antioxidant therapy.


Asunto(s)
Elementos de Respuesta Antioxidante , Diterpenos/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Animales , Antioxidantes/farmacología , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Homeostasis , Neoplasias Hepáticas/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Oxidación-Reducción , Oxígeno/química , Contaminación por Humo de Tabaco , Pez Cebra
20.
Dalton Trans ; 48(13): 4420-4428, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30865737

RESUMEN

A series of binuclear cyclometalated Pt(ii) complexes with the bridge ligand of binaphthyl quinoline were synthesized and characterized. Owing to the restriction of intramolecular motions in chiral binaphthyl linkers, the complexes exhibited two unusual metal-induced chiral components and aggregation-induced red phosphorescence. The (R,R,R)/(S,S,S) enantiopure complexes that were confirmed by X-ray diffraction, circular dichroism spectra, time-dependent density functional theory calculations, and circularly polarized luminescence did not require purification by chiral high-performance liquid chromatography and could yield unique 1D M or P hierarchical helices of helices via intermolecular noncovalent interactions. Moreover, it is the first time that racemization-induced phosphorescence enhancement has been observed.

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