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1.
J Am Chem Soc ; 146(33): 23278-23288, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39049154

ABSTRACT

Manipulating electronic polarizations such as ferroelectric or spin polarizations has recently emerged as an effective strategy for enhancing the efficiency of photocatalytic reactions. This study demonstrates the control of electronic polarizations modulated by ferroelectric and magnetic approaches within a two-dimensional (2D) layered crystal of copper indium thiophosphate (CuInP2S6) to boost the photocatalytic reduction of CO2. We investigate the substantial influence of ferroelectric polarization on the photocatalytic CO2 reduction efficiency, utilizing the ferroelectric-paraelectric phase transition and polarization alignment through electrical poling. Additionally, we explore enhancing the CO2 reduction efficiency by harnessing spin electrons through the synergistic introduction of sulfur vacancies and applying a magnetic field. Several advanced characterization techniques, including piezoresponse force microscopy, ultrafast pump-probe spectroscopy, in situ X-ray absorption spectroscopy, and in situ diffuse reflectance infrared Fourier transformed spectroscopy, are performed to unveil the underlying mechanism of the enhanced photocatalytic CO2 reduction. These findings pave the way for manipulating electronic polarizations regulated through ferroelectric or magnetic modulations in 2D layered materials to advance the efficiency of photocatalytic CO2 reduction.

2.
J Am Chem Soc ; 145(32): 17995-18006, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37550082

ABSTRACT

The acidic oxygen evolution reaction (OER) has long been the bottleneck of proton exchange membrane water electrolyzers given its harsh oxidative and corrosive environments. Herein, we suggest an effective strategy to greatly enhance both the acidic OER activity and stability of Co3O4 spinel by atomic Ru selective substitution on the octahedral Co sites. The resulting highly symmetrical octahedral Ru-O-Co collaborative coordination with strong electron coupling effect enables the direct dioxygen radical coupling OER pathway. Indeed, both experiments and theoretical calculations reveal a thermodynamically breakthrough heterogeneous diatomic oxygen mechanism. Additionally, the active Ru-O-Co units are well-maintained upon the acidic OER thanks to the electron transfer from surrounding electron-enriched tetrahedral Co atoms via bridging oxygen bonds that suppresses the overoxidation and thus dissolution of active Ru and Co species. Consequently, the prepared catalyst, even with a low Ru mass loading of ca. 42.8 µg cm-2, exhibits an attractive acidic OER performance with a low overpotential of 200 mV and a low potential decay rate of 0.45 mV h-1 at 10 mA cm-2. Our work suggests an effective strategy to significantly enhance both the acidic OER activity and stability of low-cost electrocatalysts.

3.
Small ; 19(32): e2300807, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37086117

ABSTRACT

Designing a facile strategy to prepare catalysts with highly active sites are challenging for large-scale implementation of electrochemical hydrogen production. Herein, a straightforward and eco-friendly method by high-energy mechanochemical ball milling for mass production of atomic Ru dispersive in defective MoS2 catalysts (Ru1 @D-MoS2 ) is developed. It is found that single atomic Ru doping induces the generation of S vacancies, which can break the electronic neutrality around Ru atoms, leading to an asymmetrical distribution of electrons. It is also demonstrated that the Ru1 @D-MoS2 exhibits superb alkaline hydrogen evolution enhancement, possibly attributing to this electronic asymmetry. The overpotential required to deliver a current density of 10 mA cm-2 is as low as 107 mV, which is much lower than that of commercial MoS2 (C-MoS2 , 364 mV). Further density functional theory (DFT) calculations also support that the vacancy-coupled single Ru enables much higher electronic distribution asymmetry degree, which could regulate the adsorption energy of intermediates, favoring the water dissociation and the adsorption/desorption of H*. Besides, the long-term stability test under 500 mA cm-2 further confirms the robust performance of Ru1 @D-MoS2 . Our strategy provides a promising and practical way towards large-scale preparation of advanced HER catalysts for commercial applications.

4.
Phys Chem Chem Phys ; 25(37): 25639-25653, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37721171

ABSTRACT

In the present study, synchrotron-based X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS) and X-ray excited optical luminescence (XEOL) have been used to investigate the induced defect states in metal oxide nanomaterials. Specifically, two synthesis approaches have been followed to develop unique nano-sized peanut-shaped (N-ZnO) nanostructures and micron-sized hexagonal rods (M-ZnO). XANES analysis at the Zn K-edge revealed the presence of defect states with a divalent oxidation state of zinc (Zn2+) in a tetrahedral structure. Furthermore, XAS measurements performed at the Zn L3,2-edge and O K-edge confirm higher oxygen-related defects in M-ZnO, while N-ZnO appeared to have a higher concentration of surface defects due to size confinement. Moreover, the in-line XEOL and time dependent-XEOL measurements exposed the radiative excitonic recombination phenomena occurring in the band-tailing region as a function of absorption length, X-ray energy excitation, and time. Based on the chronology developed in the defect state improvement, a possible energy band diagram is proposed to accurately locate the defect states in the two systems. Furthermore, the increased absorption intensity at the Zn L3,2-edge and the O K-edge under the UV lamp suggests delayed recombination of electrons and holes, highlighting their potential use as photo catalysts. The photocatalytic activity degrading the rhodamine B dye established M-ZnO as a superior catalyst with a rapid degradation rate and significant mineralization. Overall, this work provides valuable insights into ZnO defect states and provides a foundation for efficient advanced materials for environmental or other optoelectronic applications.

5.
Bioorg Chem ; 139: 106652, 2023 10.
Article in English | MEDLINE | ID: mdl-37390632

ABSTRACT

Primary liver cancer is one of the most common malignant cancers of the digestive system that lacks effective chemotherapeutic drugs in clinical settings. Camptothecin (CPT) and its derivatives have been approved for cancer treatment; however, their application is limited by their systemic toxicity. For lead optimization in new drug discovery stages, fluorination is an effective and robust approach to increase the bioavailability and optimize the pharmacokinetics of candidate compounds, thereby improving their efficacy. To obtain new and highly active CPT derivatives, we designed, synthesized, and evaluated two new fluorinated CPT derivatives, 9-fluorocamptothecin (A1) and 7-ethyl-9-fluorocamptothecin (A2), in this study. In vitro, A1 and A2 exhibited more robust anti-tumor activity than topotecan (TPT) in various cancer cells, particularly hepatocellular carcinoma (HCC) cells. In vivo, A1 and A2 exhibited greater anti-tumor activity than TPT in both AKT/Met induced primary HCC mouse models and implanted HepG2 cell xenografts. Acute toxicity tests revealed that A1 and A2 were not lethal and did not cause significant body weight loss at high doses. Moreover, A1 and A2 exhibited no significant toxicity in the mouse liver, heart, lung, spleen, kidney, and hematopoietic systems at therapeutic doses. Mechanistically, A1 and A2 blocked HCC cell proliferation by inhibiting the enzymatic activity of Topo I, subsequently inducing DNA damage, cell cycle arrest, and apoptosis. In summary, our results indicate that fluorination improves the anti-tumor activity of CPT while decreasing its toxicity and highlight the application potential of fluorination products A1 and A2 in clinical settings.


Subject(s)
Antineoplastic Agents , Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Animals , Mice , Camptothecin/pharmacology , Camptothecin/therapeutic use , Carcinoma, Hepatocellular/drug therapy , DNA Topoisomerases, Type I/metabolism , Liver Neoplasms/drug therapy , Topotecan/pharmacology , Topoisomerase I Inhibitors/pharmacology , Topoisomerase I Inhibitors/therapeutic use , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use
6.
Bioorg Chem ; 122: 105747, 2022 05.
Article in English | MEDLINE | ID: mdl-35338969

ABSTRACT

Based on the structural skeleton of natural products boeravinones, two types of 6H-chromeno[3,4-b]quinoline derivatives were designed and synthesized by nitrogen atom substitution strategy. Then, their cytotoxic activities were evaluated against six human tumor cell lines including HepG2 (hepatocellular carcinoma), A2780 (ovarian cancer), Hela (cervical cancer), HCT116 (colorectal cancer), SW1990 (pancreatic cancer), and MCF7 (breast cancer). The results showed that compounds ZML-8 and ZML-14 exhibited robust inhibitory activities against HepG2 cells with IC50 values of 0.58 and 1.94 µM, respectively. In addition, ZML-8 and ZML-14 showed higher selectivity against HepG2 and L-02 cells than Topotecan. Mechanistically, ZML-8 and ZML-14 not only induced cell cycle arrest in the G2/M phase and cell apoptosis, but also dose-dependently inhibited topoisomerase I activity and induced DNA damage in HepG2 cells. Molecular docking showed that ZML-8 and ZML-14 could interact with topoisomerase I-DNA complex with a similar binding mode to Topotecan. Inhibitory activities of these two compounds on topoisomerase I were then confirmed in both cell-free systems and in whole-cell lysates. Taken together, compounds ZML-8 and ZML-14 merit further development as a new generation of non-camptothecin topoisomerase I inhibitors for the treatment of cancer.


Subject(s)
Antineoplastic Agents , Ovarian Neoplasms , Antineoplastic Agents/chemistry , Apoptosis , Cell Line, Tumor , Cell Proliferation , Drug Design , Drug Screening Assays, Antitumor , Female , Humans , Molecular Docking Simulation , Topoisomerase I Inhibitors , Topoisomerase II Inhibitors/pharmacology
7.
Bioorg Chem ; 114: 105065, 2021 09.
Article in English | MEDLINE | ID: mdl-34174631

ABSTRACT

29 novel 20(S)-aminophosphonate derivatives of camptothecin were synthesized via a FeCl3 - catalyzed one-pot reaction. All of these compounds displayed similar or superior cytotoxic activity in comparison with that of Irinotecan against Hep3B, MCF-7, A-549, MDA-MB-231, KB, and multidrug-resistant (MDR) KB-vin cell lines. Out of them, compound B07 exhibited significant cytotoxicity and 10-fold improvement in activity compared to Irinotecan. Mechanistically, B07 not only induced cell apoptosis and cell cycle arrest in Hep3B and MCF-7 cells, but also inhibited Topoisomerase I activity in the cell and cell-free system in a manner similar to that of Irinotecan. In both xenograft and primary HCC mouse models, B07 showed significant anti-tumor activity and was more potent than Irinotecan. Additionally, the acute toxicity assay showed that B07 had no apparent toxicity to the mouse liver, kidney, and hemopoietic system of the FVB/N mice. Therefore, these findings indicate that compound B07 could be a potential Topoisomerase I poison drug candidate for further clinical trial.


Subject(s)
Antineoplastic Agents/pharmacology , Camptothecin/pharmacology , Drug Design , Organophosphonates/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Camptothecin/chemical synthesis , Camptothecin/chemistry , Cell Cycle/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Organophosphonates/chemical synthesis , Organophosphonates/chemistry , Structure-Activity Relationship
8.
Chem Biodivers ; 18(12): e2100633, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34643056

ABSTRACT

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 µg mL-1 . Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the ß-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.


Subject(s)
Antifungal Agents/pharmacology , Cnidium/chemistry , Coumarins/pharmacology , Fruit/chemistry , Rhizoctonia/drug effects , Acetyl Coenzyme A/antagonists & inhibitors , Acetyl Coenzyme A/biosynthesis , Adenosine Triphosphate/antagonists & inhibitors , Adenosine Triphosphate/biosynthesis , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Coumarins/chemistry , Coumarins/isolation & purification , Fatty Acids/antagonists & inhibitors , Fatty Acids/metabolism , Microbial Sensitivity Tests , Molecular Structure , Rhizoctonia/growth & development
9.
Int J Mol Sci ; 22(19)2021 Oct 07.
Article in English | MEDLINE | ID: mdl-34639194

ABSTRACT

Humulus lupulus Linn. is a traditional medicinal and edible plant with several biological properties. The aims of this work were: (1) to evaluate the in vitro antifungal activity of H. lupulus ethanolic extract; (2) to study the in vitro and in vivo antifungal activity of isoxanthohumol, an isoprene flavonoid from H. lupulus, against Botrytis cinerea; and (3) to explore the antifungal mechanism of isoxanthohumol on B. cinerea. The present data revealed that the ethanolic extract of H. lupulus exhibited moderate antifungal activity against the five tested phytopathogenic fungi in vitro, and isoxanthohumol showed highly significant antifungal activity against B. cinerea, with an EC50 value of 4.32 µg/mL. Meanwhile, it exhibited moderate to excellent protective and curative efficacies in vivo. The results of morphologic observation, RNA-seq, and physiological indicators revealed that the antifungal mechanism of isoxanthohumol is mainly related to metabolism; it affected the carbohydrate metabolic process, destroyed the tricarboxylic acid (TCA) cycle, and hindered the generation of ATP by inhibiting respiration. Further studies indicated that isoxanthohumol caused membrane lipid peroxidation, thus accelerating the death of B. cinerea. This study demonstrates that isoxanthohumol can be used as a potential botanical fungicide for the management of phytopathogenic fungi.


Subject(s)
Adenosine Triphosphate/metabolism , Antifungal Agents/pharmacology , Botrytis/drug effects , Humulus/chemistry , Lipid Peroxidation/drug effects , Xanthones/pharmacology , Botrytis/growth & development
10.
Med Res Rev ; 40(6): 2212-2289, 2020 11.
Article in English | MEDLINE | ID: mdl-32729169

ABSTRACT

Isoquinoline alkaloids, an important class of N-based heterocyclic compounds, have attracted considerable attention from researchers worldwide since the early 19th century. Over the past 200 years, many compounds from this class were isolated, and most of them and their analogs possess various bioactivities. In this review, we survey the updated literature on bioactive alkaloids and highlight research achievements of this alkaloid class during the period of 2014-2018. We reviewed over 400 molecules with a broad range of bioactivities, including antitumor, antidiabetic and its complications, antibacterial, antifungal, antiviral, antiparasitic, insecticidal, anti-inflammatory, antioxidant, neuroprotective, and other activities. This review should provide new indications or directions for the discovery of new and better drugs from the original naturally occurring isoquinoline alkaloids.


Subject(s)
Alkaloids , Anti-Infective Agents , Alkaloids/pharmacology , Anti-Infective Agents/pharmacology , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Humans , Isoquinolines/pharmacology
11.
Pestic Biochem Physiol ; 170: 104705, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32980068

ABSTRACT

Magnolia officinalis, as a well-known herb worldwide, has been widely used to treat multiple diseases for a long time. In this study, the petroleum ether extract from M. officinalis showed effective antifungal activity against seven plant pathogens (particularly against R. solani with an inhibition rate of 100.00% at 250 µg/mL). Honokiol and magnolol, isolated by the bioassay-guided method, exhibited greater antifungal activity than tebuconazole (EC50 = 3.07 µg/mL, p ≤ 0.001) against R. solani, which EC50 values were 2.18 µg/mL and 3.48 µg/mL, respectively. We used transcriptomics to explore the mechanism of action of honokiol against R. solani. Results indicated that honokiol may exert antifungal effects by blocking the oxidative phosphorylation metabolic pathway. Further studies indicated that honokiol induced ROS overproduction, disrupted the mitochondrial function, affected respiration, and blocked the TCA cycle, which eventually inhibited ATP production. Besides, honokiol also damaged cell membranes and caused morphological changes. This study demonstrated that the lignans isolated from M. officinalis possess the potential to be developed as botanical fungicides.


Subject(s)
Lignans/pharmacology , Magnolia , Antifungal Agents/pharmacology , Biological Assay , Biphenyl Compounds
12.
Pestic Biochem Physiol ; 159: 51-58, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31400784

ABSTRACT

Isoquinoline alkaloids possess broad pharmacological activities. In this study, the antifungal activity of twelve isoquinoline alkaloids, including berberine (1), jatrorrhizine (2), coptisine (3), corydaline (4), tetrahydroberberine (5), chelidonine (6), dihydrosanguinarine (7), chelerythrine (8), sanguinarine (9), palmatine (10), tetrahydropalmatine (11) and columbamine (12) were evaluated against eight plant pathogenic fungi in vitro. All the tested compounds showed varying degrees of inhibition against the eight tested plant fungi. Among them, sanguinarine exhibited high antifungal activity (EC50 ranging from 6.96-59.36 µg/mL). It displayed the best inhibitory activity against Magnaporthe oryzae (EC50 = 6.96 µg/mL), compared with azoxystrobin (EC50 = 12.04 µg/mL), and significantly suppressed spore germination of M. oryzae with the inhibition rate reaching 100% (50 µg/mL). The optical microscopy and scanning electron microscopy observations revealed that after treating M. oryzae mycelia with sanguinarine at 10 µg/mL, the mycelia appeared curved, collapsed and the cell membrane integrity was eventually damaged. Furthermore, the reactive oxygen species production, mitochondrial membrane potential and nuclear morphometry of mycelia had been changed, and the membrane function and cell proliferation of mycelia were destroyed. These results will enrich our insights into action mechanisms of antifungal activity of sanguinarine against M. oryzae.


Subject(s)
Alkaloids/pharmacology , Antifungal Agents/pharmacology , Benzophenanthridines/pharmacology , Isoquinolines/pharmacology , Berberine/analogs & derivatives , Berberine/pharmacology , Berberine Alkaloids/pharmacology , Magnaporthe/metabolism , Magnaporthe/pathogenicity , Membrane Potential, Mitochondrial/drug effects , Parasitic Sensitivity Tests , Reactive Oxygen Species/metabolism
13.
Bioorg Med Chem Lett ; 27(17): 3959-3962, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28789891

ABSTRACT

In our continuing search for camptothecin (CPT)-derived antitumor drugs, novel 7-substituted CPT derivatives incorporating piperazinyl-sulfonylamidine moieties were designed, synthesized and evaluated for cytotoxicity against five tumor cell lines (A-549, MDA-MB-231, MCF-7, KB, and KB-VIN). All of the derivatives showed promising in vitro cytotoxic activity against the tested tumor cell lines, and were more potent than irinotecan. Remarkably, most of the compounds exhibited comparable cytotoxicity against the multidrug-resistant (MDR) KB-VIN and parental KB tumor cell lines, while irinotecan lost activity completely against KB-VIN. Especially, compounds 13r and 13p (IC50 0.38 and 0.85µM, respectively) displayed the greatest cytotoxicity against the MDR KB-VIN cell line and merit further development into preclinical and clinical drug candidates for treating cancer, including MDR phenotype.


Subject(s)
Amidines/pharmacology , Antineoplastic Agents/pharmacology , Camptothecin/pharmacology , Drug Design , Piperazines/pharmacology , Amidines/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Camptothecin/chemical synthesis , Camptothecin/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Piperazine , Piperazines/chemistry , Structure-Activity Relationship
14.
Bioorg Med Chem Lett ; 27(20): 4694-4697, 2017 10 15.
Article in English | MEDLINE | ID: mdl-28927790

ABSTRACT

Fluorination is a well-known strategy for improving the bioavailability of bioactive molecules in the lead optimization phase of drug discovery projects. In an attempt to improve the antitumor activity of camptothecins (CPTs), novel 10-fluoro-CPT derivatives were designed, synthesized and evaluated for cytotoxicity against five human cancer cell lines (A-549, MDA-MB-231, KB, KB-VIN and MCF-7). All of the derivatives showed more potent in vitro cytotoxic activity than the clinical CPT-derived drug irinotecan against the tumor cell lines tested, and most of them showed comparable or superior potency to topotecan. Remarkably, compounds 16b (IC50, 67.0nM) and 19b (IC50, 99.2nM) displayed the highest cytotoxicity against the multidrug-resistant (MDR) KB-VIN cell line and merit further development as preclinical drug candidates for treating cancer, including MDR phenotype. Our study suggested that incorporation of a fluorine atom into position 10 of CPT is an effective method for discovering new potent CPT derivatives.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Camptothecin/analogs & derivatives , Camptothecin/pharmacology , Drug Design , Antineoplastic Agents/chemistry , Camptothecin/chemical synthesis , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Drug Screening Assays, Antitumor , Fluorine/chemistry , Humans , Structure-Activity Relationship , Topotecan/pharmacology
15.
ACS Nano ; 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39484823

ABSTRACT

Single-atom catalysts are promising for electrocatalytic CO2 conversion but face challenges in controllable syntheses. Herein, a facile selenic acid etching-assisted strategy has been developed to fabricate a hybrid metal-semimetal dual single-atom catalyst for electrocatalytic CO2 reduction. This strategy enables the simultaneous generation of monodisperse active sites and hierarchical morphologies with hollow nanostructures. The as-obtained catalyst with Fe-Se dual single-atom sites supported by porous nitrogen-doped carbon (FeSe-NC) shows exceptional catalytic activity and CO selectivity, delivering a Faradaic efficiency (FE) of >97% with industrially comparable jCO, superior to the Fe single-atom catalyst. Moreover, the FeSe-NC-based rechargeable Zn-CO2 battery delivers a high power density (2.01 mW cm-2) and outstanding FECO (>90%), as well as excellent cycling stability. Experimental results together with theoretical calculations reveal that the etching-induced defects and the Se-modulated Fe centers with asymmetrical polarized charge distributions synergistically facilitate the key intermediate *CO desorption and thus accelerate the CO2-to-CO conversion.

16.
Nat Prod Res ; : 1-10, 2024 Aug 18.
Article in English | MEDLINE | ID: mdl-39155512

ABSTRACT

With the intention of advancing our research on diverse C-20 derivatives of camptothecin (CPT), 38 CPT derivatives bearing sulphonamide and sulfonylurea chemical scaffolds and different substituent groups have been designed, synthesised and evaluated in vitro for cytotoxicity against four tumour cell lines, A-549 (lung carcinoma), KB (nasopharyngeal carcinoma), MDA-MB-231 (triple-negative breast cancer) and KBvin (an MDR KB subiline). As a result, all the synthesised compounds showed promising in vitro cytotoxic activity against the four cancer cell lines tested, and were more potent than irinotecan. Importantly, compounds 12b, 12f, 12j and 13 l possessed better antiproliferative activity against all tested tumour cell lines with IC50 values of 0.0118 - 0.5478 µM, and resulted approximately 3 to 4 times more cytotoxic than topotecan against multidrug-resistant KBvin subline. Convincing evidences are achieved that incorporation of sulphonamide and sulfonylurea motifs into position-20 of camptothecin confers markedly enhanced cytotoxic activity against cancer cell lines.

17.
J Agric Food Chem ; 72(13): 6988-6997, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38506764

ABSTRACT

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv oryzae (Xoo) is extremely harmful to rice production. The traditional control approach is to use bactericides that target key bacterial growth factors, but the selection pressure on the pathogen makes resistant strains the dominant bacterial strains, leading to a decline in bactericidal efficacy. Type III secretion system (T3SS) is a conserved and critical virulence factor in most Gram-negative bacteria, and its expression or absence does not affect bacterial growth, rendering it an ideal target for creating drugs against Gram-negative pathogens. In this work, we synthesized a range of derivatives from cryptolepine and neocryptolepine. We found that compound Z-8 could inhibit the expression of Xoo T3SS-related genes without affecting the growth of bacteria. an in vivo bioassay showed that compound Z-8 could effectively reduce the hypersensitive response (HR) induced by Xoo in tobacco and reduce the pathogenicity of Xoo in rice. Furthermore, it exhibited synergy in control of bacterial leaf blight when combined with the quorum quenching bacterial F20.


Subject(s)
Alkaloids , Indole Alkaloids , Oryza , Quinolines , Xanthomonas , Oryza/genetics , Type III Secretion Systems/genetics , Bacteria/metabolism , Xanthomonas/genetics , Plant Diseases/prevention & control , Plant Diseases/microbiology
18.
Int J Ophthalmol ; 17(3): 528-536, 2024.
Article in English | MEDLINE | ID: mdl-38721515

ABSTRACT

AIM: To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) compared to those of PPV with subsequent cataract surgery. METHODS: This multicenter randomized controlled trial was conducted in three Chinese hospitals on patients with PDR, aged >45y, with mild cataracts. The participants were randomly assigned to the combined (PPV combined with simultaneously cataract surgery, i.e., phacovitrectomy) or subsequent (PPV with subsequent cataract surgery 6mo later) group and followed up for 12mo. The primary outcome was the change in best-corrected visual acuity (BCVA) from baseline to 6mo, and the secondary outcomes included complication rates and medical expenses. RESULTS: In total, 129 patients with PDR were recruited and equally randomized (66 and 63 in the combined and subsequent groups respectively). The change in BCVA in the combined group [mean, 36.90 letters; 95% confidence interval (CI), 30.35-43.45] was significantly better (adjusted difference, 16.43; 95%CI, 8.77-24.08; P<0.001) than in the subsequent group (mean, 22.40 letters; 95%CI, 15.55-29.24) 6mo after the PPV, with no significant difference between the two groups at 12mo. The overall surgical risk of two sequential surgeries was significantly higher than that of the combined surgery for neovascular glaucoma (17.65% vs 3.77%, P=0.005). No significant differences were found in the photocoagulation spots, surgical time, and economic expenses between two groups. In the subsequent group, the duration of work incapacity (22.54±9.11d) was significantly longer (P<0.001) than that of the combined group (12.44±6.48d). CONCLUSION: PDR patients aged over 45y with mild cataract can also benefit from early lens extraction during PPV with gratifying effectiveness, safety and convenience, compared to sequential surgeries.

19.
Int Immunopharmacol ; 111: 109114, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35933747

ABSTRACT

Intestinal ischemia/reperfusion (II/R) is a clinical event associated with high morbidity and mortality. AMP-activated protein kinase (AMPK), a central cellular energy sensor, is associated with oxidative stress and inflammation. However, whether the AMPK is involved in the II/R-induced intestinal injury and the underlying mechanism is yet to be elucidated. Propofol has a protective effect on organs; yet, its specific mechanism of action remains unclear. This study explored the role of the AMPK-Sirt1-autophagy pathway in intestinal injury, and whether propofol could reduce intestinal injury and investigated the mechanisms in a rat model of II/R injury as well as a cell model (IEC-6 cells) of hypoxia/reoxygenation (H/R). Propofol, AMPK agonist (AICAR) and AMPK inhibitor (Compound C) were then administered, respectively. The histopathological changes, cell viability and apoptosis were detected. Furthermore, the levels of proinflammatory factors, the activities of oxidative stress, diamine oxidase, and signaling pathway were also analyzed. The results demonstrated that the AMPK-Sirt1-autophagy pathway of intestine was activated after II/R or H/R. Propofol could further activate the pathway, which reduced intestinal injury, inhibited apoptosis, reversed inflammation and oxidative stress, and improved the 24-hour survival rate in II/R rats in vivo, and attenuated H/R-induced IEC-6 cell injury, oxidative stress, and apoptosis in vitro, as fine as changes in AICAR treatment. Compound C abrogated the protective effect of propofol on II/R and H/R-induced injury. These results suggested a crucial effect of AMPK on the mechanism of intestinal injury and might provide a new insight into the mechanism of propofol reducing II/R injury.


Subject(s)
Intestinal Diseases , Propofol , Reperfusion Injury , AMP-Activated Protein Kinases/metabolism , Animals , Apoptosis , Autophagy , Inflammation , Intestines/pathology , Ischemia , Propofol/pharmacology , Propofol/therapeutic use , Rats , Reperfusion Injury/metabolism , Sirtuin 1/metabolism
20.
Oxid Med Cell Longev ; 2022: 8729398, 2022.
Article in English | MEDLINE | ID: mdl-36035210

ABSTRACT

Cerebral ischemia/reperfusion (I/R) injury is a clinical event associated with high morbidity and mortality. Neuroinflammation plays a crucial role in the pathogenesis of I/R-induced brain injury and cognitive decline. Low-density lipoprotein receptor-related protein-1 (LRP1) can exert strong neuroprotection in experimental intracerebral hemorrhage. However, whether LRP1 can confer neuroprotective effects after cerebral I/R is yet to be elucidated. The present study is aimed at investigating the effects of LRP1 activation on cerebral I/R injury and deducing the underlying mechanism involving TXNIP/NLRP3 signaling pathway. Cerebral I/R injury was induced in mice by bilateral common carotid artery occlusion. LPR1 ligand, apoE-mimic peptide COG1410, was administered intraperitoneally. To elucidate the underlying mechanism, overexpression of TXNIP was achieved via the hippocampal injection of AAV-TXNIP before COG1410 treatment. Neurobehavioral tests, brain water content, immunofluorescence, Western blot, enzyme-linked immunosorbent assay, HE, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were performed. Our results showed that the expressions of endogenous LRP1, TXNIP, NLRP3, procaspase-1, and cleaved caspase-1 were increased after cerebral I/R. COG1410 significantly ameliorated cerebral I/R-induced neurobehavioral deficits, brain edema, histopathological damage, and poor survival rate. Interestingly, COG1410 inhibited microglia proinflammatory polarization and promoted anti-inflammatory polarization, decreased oxidative stress, attenuated apoptosis, and inhibited the expression of the TXNIP/NLRP3 signaling pathway. However, the benefits of COG1410 were abolished by TXNIP overexpression. Thus, our study suggested that LRP1 activation with COG1410 attenuated cerebral I/R injury at least partially related to modulating microglial polarization through TXNIP/NLRP3 signaling pathway in mice. Thus, COG1410 treatment might serve as a promising therapeutic approach in the management of cerebral I/R patients.


Subject(s)
Brain Ischemia , Cognitive Dysfunction , Low Density Lipoprotein Receptor-Related Protein-1 , Oxidative Stress , Reperfusion Injury , Animals , Carrier Proteins , Caspase 1 , Cognitive Dysfunction/prevention & control , Inflammasomes , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Mice , NLR Family, Pyrin Domain-Containing 3 Protein , Neuroinflammatory Diseases , Reperfusion Injury/prevention & control , Signal Transduction , Thioredoxins
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