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1.
ACS Appl Mater Interfaces ; 16(11): 13961-13971, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38456427

ABSTRACT

The advancement of lead-free glass ceramics (GCs) possessing appropriate energy storage characteristics is crucial for the renewable energy and electronics industry. In this study, we synthesized lead-free GCs predominantly composed of the tungsten bronze phase, Ba3.3Nb10O28.3. Ab initio molecular dynamics initially reveal nonuniform distribution within the Ba/Nb-O regions in niobite glassy melts, offering valuable insights for the subsequent crystallization process. The proposal of a B-site engineering strategy is suggested, which entails the concurrent reduction of grain size and augmentation of the band gap in tungsten bronze GCs doped with Ta. This approach results in a substantial enhancement of the dielectric breakdown strength (BDS). Phase-field simulations have indicated that the refinement of grain sizes plays a pivotal role in augmenting the local electric field distribution and breakdown path, thereby contributing to the enhancement of BDS. As a consequence of these modifications, a notably high recoverable energy density (Wrec) of 5.23 J/cm3 can be achieved, accompanied by an ultrahigh efficiency (η) of 94%, and superior thermal stability in energy storage. These outcomes are particularly evident in the case of 2 mol % Ta2O5-doped P2O5-K2O-BaO-Bi2O3-TeO2-Nb2O5 (PKBBTN-T) GCs, where the Wrec and η can be determined to be 2.87 ± 3% J/cm3 and 95.46 ± 4%, respectively, over a temperature range spanning from 20 to 150 °C. Additionally, this specimen exhibits an exceptionally high discharge energy density (Wdis) of 4.01 J/cm3. This comprehensive investigation, comprising experimental and theoretical analyses, establishes an effective pathway and paradigm for the development of dielectric materials with ultrahigh energy storage properties.

2.
Front Psychiatry ; 15: 1333528, 2024.
Article in English | MEDLINE | ID: mdl-38525257

ABSTRACT

Background: Mental health has been found to be associated with risk of osteoarthritis (OA), but the causal relationship was not fully clarified. Methods: Two-sample Mendelian randomization (MR) study was conducted to investigate the causal relationship between neuroticism (n = 329,821) and the two most frequently affected parts of osteoarthritis (OA) (knee OA: case/control =24,955/378,169; hip OA: case/control = 15,704/378,169) using large scale summary genome-wide association study (GWAS) data. Inverse variance weighted (IVW), weighted median, and MR-Egger were used to estimate the causal effects. Multiple sensitivity analyses were conducted to examine the robustness of the causal estimates. Multivariable MR analysis was used to estimate the direct effects of neuroticism on OA after accounting for the other OA risk factors. Two-step MR approach was employed to explore the potential mediators of the causal relationship. Results: Univariable MR analysis indicated that 1-SD increase in genetically predicted neuroticism score was associated with an increased risk of knee OA (IVW: OR, 1.17; 95% CI, 1.087-1.26; p = 2.72E-05) but not with hip OA. The causal effects remained significant after accounting for the effects of BMI, alcohol drinking, and vigorous physical activity but were attenuated with adjustment of smoking. Further mediation analysis revealed that smoking initiation mediated a significant proportion of the causal effects of neuroticism on knee OA (proportion of mediation effects in total effects: 22.3%; 95% CI, 5.9%-38.6%; p = 7.60E-03). Conclusions: Neuroticism has significant causal effects on knee OA risk. Smoking might partly mediate the causal relationship. Further studies were warranted to explore the underlying mechanisms and potential use of neuroticism management for OA treatment.

3.
Natl Sci Rev ; 11(1): nwae020, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38332843

ABSTRACT

Mounting evidence suggests that strategies combining DNA-damaging agents and stimulator of interferon genes (STING) agonists are promising cancer therapeutic regimens because they can amplify STING activation and remodel the immunosuppressive tumor microenvironment. However, a single molecular entity comprising both agents has not yet been developed. Herein, we designed two PtIV-MSA-2 conjugates (I and II) containing the DNA-damaging chemotherapeutic drug cisplatin and the innate immune-activating STING agonist MSA-2; these conjugates showed great potential as multispecific small-molecule drugs against pancreatic cancer. Mechanistic studies revealed that conjugate I upregulated the expression of transcripts associated with innate immunity and metabolism in cancer cells, significantly differing from cisplatin and MSA-2. An analysis of the tumor microenvironment demonstrated that conjugate I could enhance the infiltration of natural killer (NK) cells into tumors and promote the activation of T cells, NK cells and dendritic cells in tumor tissues. These findings indicated that conjugate I, which was created by incorporating a Pt chemotherapeutic drug and STING agonist into one molecule, is a promising and potent anticancer drug candidate, opening new avenues for small-molecule-based cancer metalloimmunotherapy.

4.
Angew Chem Int Ed Engl ; 63(9): e202317613, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38195970

ABSTRACT

Most of the anticancer compounds synthesized by chemists are primarily evaluated for their direct cytotoxic effects at the cellular level, often overlooking the critical role of the immune system. In this study, we developed a patient-derived, T-cell-retaining tumor organoid model that allows us to evaluate the anticancer efficacy of chemical drugs under the synergistic paradigm of antigen-specific T-cell-dependent killing, which may reveal the missed drug hits in the simple cytotoxic assay. We evaluated clinically approved platinum (Pt) drugs and a custom library of twenty-eight PtIV compounds. We observed low direct cytotoxicity of Pt drugs, but variable synergistic effects in combination with immune checkpoint inhibitors (ICIs). In contrast, the majority of PtIV compounds exhibited potent tumor-killing capabilities. Interestingly, several PtIV compounds went beyond direct tumor killing and showed significant immunosynergistic effects with ICIs, outstanding at sub-micromolar concentrations. Among these, Pt-19, PtIV compounds with cinnamate axial ligands, emerged as the most therapeutically potent, demonstrating pronounced immunosynergistic effects by promoting the release of cytotoxic cytokines, activating immune-related pathways and enhancing T cell receptor (TCR) clonal expansion. Overall, this initiative marks the first use of patient-derived immunocompetent tumor organoids to explore and study chemotherapy, advancing their path toward more effective small molecule drug discovery.


Subject(s)
Antineoplastic Agents , Humans , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Platinum/chemistry , T-Lymphocytes , Organoids
5.
J Med Chem ; 66(16): 11351-11364, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37578941

ABSTRACT

Interplay between breast cancer (BC) cells and the tumor microenvironment (TME) influences the outcome of cancer treatment. Aberrant activation of signal transducer and activator of transcription 3 (STAT3) promotes the interaction and causes immunosuppression and drug resistance. Platinum(IV) complexes SPP and DPP bearing pterostilbene-derived axial ligand(s) were synthesized to inhibit the JAK2-STAT3 pathway in BC cells and regulate the TME. These complexes exerted remarkable antiproliferative activity against the triple-negative BC cells, suppressed the expression of phosphorylated STAT3 and STAT3-related cyclooxygenase-2 and IL-6, and activated caspase-3 and cleaved poly ADP-ribose polymerase, preventing the repair of DNA lesions and inducing apoptosis. Furthermore, DPP promoted the maturation and antigen presentation of dendritic cells, repressed the proliferation and differentiation of myeloid-derived suppressor cells and regulatory T cells, and facilitated the expansion of T cells. As a consequence, DPP showed excellent anticancer activity against BC with almost no general toxicity in vivo as a potential chemoimmunotherapeutic agent.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Platinum/pharmacology , Platinum/metabolism , Cell Line, Tumor , STAT3 Transcription Factor/metabolism , Tumor Microenvironment , Apoptosis , Cell Proliferation
6.
Chem Sci ; 14(16): 4375-4389, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37123182

ABSTRACT

Activating the cyclic GMP-AMP synthase-stimulator of the interferon gene (cGAS-STING) pathway is a promising immunotherapeutic strategy for cancer treatment. Manganese(ii) complexes MnPC and MnPVA (P = 1,10-phenanthroline, C = chlorine, and VA = valproic acid) were found to activate the cGAS-STING pathway. The complexes not only damaged DNA, but also inhibited histone deacetylases (HDACs) and poly adenosine diphosphate-ribose polymerase (PARP) to impede the repair of DNA damage, thereby promoting the leakage of DNA fragments into cytoplasm. The DNA fragments activated the cGAS-STING pathway, which initiated an innate immune response and a two-way communication between tumor cells and neighboring immune cells. The activated cGAS-STING further increased the production of type I interferons and secretion of pro-inflammatory cytokines (TNF-α and IL-6), boosting the tumor infiltration of dendritic cells and macrophages, as well as stimulating cytotoxic T cells to kill cancer cells in vitro and in vivo. Owing to the enhanced DNA-damaging ability, MnPC and MnPVA showed more potent immunocompetence and antitumor activity than Mn2+ ions, thus demonstrating great potential as chemoimmunotherapeutic agents for cancer treatment.

7.
Nat Commun ; 14(1): 800, 2023 02 13.
Article in English | MEDLINE | ID: mdl-36781887

ABSTRACT

Temporal control of delivery and release of drugs in tumors are important in improving therapeutic outcomes to patients. Here, we report a sequential stimuli-triggered in situ self-assembly and disassembly strategy to direct delivery and release of theranostic drugs in vivo. Using cisplatin as a model anticancer drug, we design a stimuli-responsive small-molecule cisplatin prodrug (P-CyPt), which undergoes extracellular alkaline phosphatase-triggered in situ self-assembly and succeeding intracellular glutathione-triggered disassembly process, allowing to enhance accumulation and elicit burst release of cisplatin in tumor cells. Compared with cisplatin, P-CyPt greatly improves antitumor efficacy while mitigates off-target toxicity in mice with subcutaneous HeLa tumors and orthotopic HepG2 liver tumors after systemic administration. Moreover, P-CyPt also produces activated near-infrared fluorescence (at 710 nm) and dual photoacoustic imaging signals (at 700 and 750 nm), permitting high sensitivity and spatial-resolution delineation of tumor foci and real-time monitoring of drug delivery and release in vivo. This strategy leverages the advantages offered by in situ self-assembly with those of intracellular disassembly, which may act as a general platform for the design of prodrugs capable of improving drug delivery for cancer theranostics.


Subject(s)
Antineoplastic Agents , Nanoparticles , Neoplasms , Prodrugs , Animals , Mice , Cisplatin/pharmacology , Precision Medicine , Cell Line, Tumor , Neoplasms/drug therapy
8.
Clin Rev Allergy Immunol ; 64(3): 284-320, 2023 Jun.
Article in English | MEDLINE | ID: mdl-35031958

ABSTRACT

Systemic sclerosis (SSc) is an intractable autoimmune disease with unmet medical needs. Conventional immunosuppressive therapies have modest efficacy and obvious side effects. Targeted therapies with small molecules and antibodies remain under investigation in small pilot studies. The major breakthrough was the development of autologous haematopoietic stem cell transplantation (AHSCT) to treat refractory SSc with rapidly progressive internal organ involvement. However, AHSCT is contraindicated in patients with advanced visceral involvement. Mesenchymal stem cells (MSCs) which are characterized by immunosuppressive, antifibrotic and proangiogenic capabilities may be a promising alternative option for the treatment of SSc. Multiple preclinical and clinical studies on the use of MSCs to treat SSc are underway. However, there are several unresolved limitations and safety concerns of MSC transplantation, such as immune rejections and risks of tumour formation, respectively. Since the major therapeutic potential of MSCs has been ascribed to their paracrine signalling, the use of MSC-derived extracellular vesicles (EVs)/secretomes/exosomes as a "cell-free" therapy might be an alternative option to circumvent the limitations of MSC-based therapies. In the present review, we overview the current knowledge regarding the therapeutic efficacy of MSCs in SSc, focusing on progresses reported in preclinical and clinical studies using MSCs, as well as challenges and future directions of MSC transplantation as a treatment option for patients with SSc.


Subject(s)
Autoimmune Diseases , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Scleroderma, Systemic , Humans , Scleroderma, Systemic/therapy , Immunosuppression Therapy , Immunomodulation
9.
Angew Chem Int Ed Engl ; 62(2): e202213337, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36259513

ABSTRACT

Triggering receptor expressed on myeloid cells-2 (TREM2) is a key pro-tumorigenic marker of tumor-infiltrating macrophages, showing potent immunosuppressive activity in tumor microenvironment. A platinum(IV) complex OPA derived from oxaliplatin (OP) and artesunate (ART) exhibited direct cytotoxicity against human colon cancer cells and immunomodulatory activity to inhibit TREM2 on macrophages in vitro and vivo. Furthermore, OPA deterred the tumor growth in mouse models bearing MC38 colorectal tumor by reducing the number of CD206+ and CX3 CR1+ immunosuppressive macrophages; it also promoted the expansion and infiltration of immunostimulatory dendritic, cytotoxic T, and natural killer cells. OPA is the first small-molecular TREM2 inhibitor capable of relieving immunosuppressive tumor microenvironment and enhancing chemical anticancer efficiency of a platinum drug, thus showing typical characteristics of a chemoimmunotherapeutic agent.


Subject(s)
Antineoplastic Agents , Colonic Neoplasms , Animals , Mice , Humans , Platinum/pharmacology , Platinum/therapeutic use , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Myeloid Cells/pathology , Macrophages , Immunosuppressive Agents/pharmacology , Colonic Neoplasms/drug therapy , Tumor Microenvironment , Membrane Glycoproteins , Receptors, Immunologic
10.
NPJ Vaccines ; 7(1): 168, 2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36535957

ABSTRACT

Respiratory syncytial virus (RSV) infection in children is the most common viral respiratory infection and can cause severe lung damage or death. There is no licensed vaccine for preventing RSV infection. Previously we demonstrated that an RSV vaccine, BARS13, consisting of recombinant G protein from E. coli plus cyclosporine A (CsA) as an immune-modulator, can protect animals from RSV challenge without inducing vaccine-enhanced disease (VED). To maximize the efficacy of such a vaccine, we introduced RSV pre-fusion F protein (pre-F) to form a new vaccine comprised of the pre-F and G proteins with the CsA. Two intramuscular immunizations with the vaccine induced a higher level of neutralizing antibodies against RSV and protected mice from RSV challenge without incurring VED. Interestingly, the addition of the pre-F to the vaccine facilitated anti-G antibody production and protection from RSV infection mainly via induction of antibodies against the central conserved domain (CCD) of the G protein which correlated with blocking the CX3C-CX3CR1 interaction. A 15 amino acid sequence (FP4) within the F2 region of pre-F served as a CD4+ Th epitope to facilitate the anti-G antibody response. Collectively, such a combination of the FP4 peptide with the G protein and CsA provides a novel strategy for developing a safe and maximally effective recombinant G protein-containing RSV vaccine.

11.
Biosensors (Basel) ; 12(11)2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36421144

ABSTRACT

Photodynamic therapy (PDT) has attracted much attention in the field of anticancer treatment. However, PDT has to face challenges, such as aggregation caused by quenching of reactive oxygen species (ROS), and short 1O2 lifetime, which lead to unsatisfactory therapeutic effect. Aggregation-induced emission luminogen (AIEgens)-based photosensitizers (PSs) showed enhanced ROS generation upon aggregation, which showed great potential for hypoxic tumor treatment with enhanced PDT effect. In this review, we summarized the design strategies and applications of AIEgen-based PSs with improved PDT efficacy since 2019. Firstly, we introduce the research background and some basic knowledge in the related field. Secondly, the recent approaches of AIEgen-based PSs for enhanced PDT are summarized in two categories: (1) organelle-targeting PSs that could cause direct damage to organelles to enhance PDT effects, and (2) PSs with tumor-targeting abilities to selectively suppress tumor growth and reduce side effects. Finally, current challenges and future opportunities are discussed. We hope this review can offer new insights and inspirations for the development of AIEgen-based PSs for better PDT effect.


Subject(s)
Neoplasms , Photochemotherapy , Humans , Reactive Oxygen Species , Photosensitizing Agents/therapeutic use , Neoplasms/drug therapy , Neoplasms/pathology , Organelles/pathology
12.
Vet Microbiol ; 271: 109487, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35714527

ABSTRACT

Senecavirus A (SVA), formerly known as Seneca Valley virus, belongs to the genus Senecavirus in the family Picornaviridae. SVA has a single-stranded, positive-sense RNA genome, which is actually an mRNA that initiates translation via its own internal ribosome entry site (IRES). The SVA IRES has been demonstrated to be the hepatitis C virus (HCV)-like IRES, containing eight stem-loop domains: domain (D)II, DIIIa, DIIIb, DIIIc, DIIId1, DIIId2, DIIIe and DIIIf. In this study, stem-forming motifs (SFMs) in the eight domains were independently subjected to site-directed mutagenesis (SDM) to construct eight SVA minigenomes for dual-luciferase reporter assay. The result suggested that except the DII, the other seven domains were closely evolved in the IRES activity. Subsequently, a full-length SVA cDNA clone tagged with a reporter gene was genetically modified to construct eight SFM-mutated ones, separately transfected into BSR-T7/5 cells in an attempt to rescue replication-competent SVAs. Nevertheless, no virus was successfully rescued from its own cDNA clone, implying each of the putative domains necessary in SVA IRES for viral replication. Further, we attempted to rescue replication-competent SVA via pairwise transfection of cDNA clones. Out of 28 combinations of co-transfection, four were demonstrated to be able to rescue replication-competent SVAs. Sanger sequencing showed that all four viruses had the wild-type IRES genotype, suggesting the occurrence of putative copy-choice recombination between two IRES-modifying genomes.


Subject(s)
Picornaviridae , RNA, Viral , Animals , DNA, Complementary , Internal Ribosome Entry Sites/genetics , Picornaviridae/genetics , RNA, Viral/genetics , Transfection/veterinary
13.
Inorg Chem ; 60(24): 18567-18574, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34826221

ABSTRACT

Specimen differences, tissue-dependent background fluorescence and scattering, and deviated specimen position and sensor concentration make optical imaging for labile copper fluctuation in animals questionable, and a signal comparison between specimens is infeasible. We proposed ratiometric optical imaging as an alternative to overcome these disadvantages, and a near-infrared (NIR) ratiometric sensor, BDPS1, was devised therefore by conjugating boron dipyrromethene (BODIPY) with 4-aminostyrene and modifying the 4-amino group as a Cu+ chelator. BDPS1 possessed an excitation ratiometric copper-sensing ability to show the ratio of NIR emission (710 nm) upon excitation at 600 nm to that at 660 nm, Fex600/Fex660, increasing from 2.8 to 10.7. This sensor displayed still the opposite copper response of its internal charge transfer (ICT; 670 nm) and local (581 nm) emission bands. Ratiometric imaging with this sensor disclosed a higher labile copper region near the nucleus apparatus, and HEK-293T cells were more sensitive to copper incubation than MCF-7 cells. Dual excitation ratiometric imaging with this sensor realized tracking of labile copper fluctuation in mice, and the whole-body imaging found that tail intravenous injection of CUTX-101, a therapeutical agent for Menkes disease, led to a distinct labile copper increase in the upper belly. The ex vivo imaging of the resected viscera of mice revealed that CUTX-101 injection enhanced the labile copper level in the liver, intestine, lung, and gall bladder in sequence, yet the kidney, heart, and spleen showed almost no response. This study indicated that modifying BODIPY as an extended ICT fluorophore, with its electron-donating group being derived as a metal chelator, is an effective design rationale of NIR ratiometric sensors for copper tracking in vivo/ex vivo.


Subject(s)
Porphobilinogen/analogs & derivatives , Boron
14.
PhytoKeys ; 180: 141-156, 2021.
Article in English | MEDLINE | ID: mdl-34408537

ABSTRACT

This paper reports on the presence of one generic and six specific new records of Cyperaceous species for the flora of Nepal. Amongst the new discoveries are the genus Machaerina, alongside species: Eleocharisochrostachys, Fimbristylisacuminata, F.ferruginea, F.nutans, F.thomsonii and Scleriarugosa. The taxonomy and distribution of Actinoscirpusgrossus, Fimbristylissalbundia and Fuirenaumbellata in Nepal are clarified through notes on nomenclature, description, distribution, specimen examination, identification keys and photographs.

15.
ACS Appl Mater Interfaces ; 13(21): 24833-24855, 2021 Jun 02.
Article in English | MEDLINE | ID: mdl-34014637

ABSTRACT

Sr0.7Bi0.2TiO3 (SBT) is a promising pulse energy storage material due to minor hysteresis, but its low maximum polarization (Pmax) is bad for energy storage. K+-Bi3+ defect pairs were introduced into the A-site of SBT to obtain Sr0.35Bi0.35K0.25TiO3 (SBKT) with larger Pmax. Through first-principles calculations, we determined that the introduction of defect pairs destroys the paraelectric order phase and increases local polarization, resulting in more and larger polar nanoregion (PNR) formation. On this basis, doping NaNbO3 (NN) in A- and B-sites of SBKT increases the cationic disorder and ferroelectric destabilization, further destroying the long-range order structure and forming more PNRs with smaller sizes. This enhances relaxation and decreases remnant polarization, and the broadened dielectric peak enables 0.85SBKT-0.15NN to meet the X7R specification. Furthermore, the decreased grain size and oxygen vacancy, increased thermal conductivity, and weakened local electric field (simulated by COMSOL) increase the dielectric breakdown strength (BDS). As a result, 0.95SBKT-0.05NN exhibits a high energy storage density (W) of 2.45 J/cm3 with a high efficiency of 93.1%, a high pulsed discharge energy density of 2.1 J/cm3, and a high power density of 54.1 MW/cm3 at 220 kV/cm. The energy storage properties show excellent stability of temperature (-55 to 150 °C), frequency (10-500 Hz), and cycling (105 cycles). Notably, for the pulse charge-discharge properties, 0.95SBKT-0.05NN shows great fatigue resistance during 105 cycles under 25 and 150 °C, accompanied by excellent thermal stability. Moreover, the BDS and Pmax of 0.95SBKT-0.05NN sintered in O2 further enhance. A higher W of 2.92 J/cm3 with a high efficiency of 89% at 250 kV/cm is achieved. Therefore, 0.95SBKT-0.05NN shows great application potential for pulse energy storage. In this work, we provide a novel strategy and systematic in-depth study for improving the energy storage properties of SBT.

16.
Angew Chem Int Ed Engl ; 60(15): 8174-8181, 2021 04 06.
Article in English | MEDLINE | ID: mdl-33656228

ABSTRACT

Limited therapeutic efficacy to hypoxic and refractory solid tumors has hindered the practical application of photodynamic therapy (PDT). Two new benzothiophenylisoquinoline (btiq)-derived cyclometalated IrIII complexes, IrL1 and MitoIrL2, were constructed as potent photosensitizers, with the latter being designed for mitochondria accumulation. Both complexes demonstrated a type I PDT process and caused photoinduced ferroptosis in tumor cells under hypoxia. This ferroptosis featured lipid peroxide accumulation, mitochondria shrinkage, down-regulation of glutathione peroxidase 4 (GPX4), and ferrostatin-1 (Fer-1)-inhibited cell death. Upon photoirradiation under hypoxia, mitochondria targeting MitoIrL2 caused mitochondria membrane potential (MMP) collapse, ATP production suppression, and induced cell apoptosis. The synergetic effect of ferroptosis and apoptosis causes MitoIrL2 to outperform IrL1 in inhibiting the growth of MCF-7, PANC-1, MDA-MB-231 cells and multicellular spheroids. This study demonstrates the first example of ferroptosis induced by photosensitizing IrIII complexes. Moreover, the synergism of ferroptosis and apoptosis provides a promising approach for combating hypoxic solid tumors through type I PDT processes.


Subject(s)
Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Ferroptosis/drug effects , Iridium/pharmacology , Photosensitizing Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Coordination Complexes/chemistry , Drug Screening Assays, Antitumor , Humans , Iridium/chemistry , Photochemical Processes , Photosensitizing Agents/chemistry
17.
J Inorg Biochem ; 218: 111394, 2021 05.
Article in English | MEDLINE | ID: mdl-33647541

ABSTRACT

Photodynamic therapy (PDT) has attracted extensive attention in cancer treatment because of its minimum trauma, less side effects, and so on. Photosensitizers, as one of the core elements of PDT, usually have to face problems such as poor water solubility and light stability, lack of targeting, and other problems, which seriously affect the therapeutic effect. In this work, two BODIPY (boron-dipyrromethene)-based monofunctional Pt (II) complexes, 1a and 2a, were designed and synthesized, and their PDT effect was studied. The Pt atom improved the singlet oxygen quantum yield (0.19 for 1a and 0.14 for 2a, respectively), which effectively improves the efficiency of PDT. MTT assay confirmed that the short time photo-irradiation distinctly promoted antitumor cytotoxicity of Pt (II) compounds against different cell lines. For 1a under irradiation, the IC50 value of cancer cell lines were 13.1 µM for HeLa cells and 7.6 µM for MCF-7 cells, while those of normal cell lines were 32.4 µM for HBL-100 cells and 48.6 µM for L02 cells. The results demonstrated that 1a showed specific phototoxicity to cancer cells. This specific selectivity could be attributed to the synergistic effect of increased cellular uptake (determined by ICP-MS) and higher ROS generation (detected by Cell ROX Deep Red) in cancer cells after irradiation. This study laid the foundation for the future design and synthesis of effective PDT photosensitizers.


Subject(s)
Antineoplastic Agents/pharmacology , Boron Compounds/chemistry , Coordination Complexes/pharmacology , Neoplasms/drug therapy , Organoplatinum Compounds/pharmacology , Photochemotherapy/methods , Photosensitizing Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation , Cell Survival , Coordination Complexes/chemistry , HeLa Cells , Humans , Light , MCF-7 Cells , Neoplasms/pathology , Organoplatinum Compounds/chemistry , Photosensitizing Agents/chemistry , Singlet Oxygen/metabolism
18.
Chem Sci ; 11(32): 8495-8501, 2020 Jul 29.
Article in English | MEDLINE | ID: mdl-34123110

ABSTRACT

Real-time imaging of fluctuations in intracellular glutathione (GSH) concentrations is critical to understanding the mechanism of GSH-related cisplatin-resistance. Here, we describe a ratiometric fluorescence probe based on a reversible Michael addition reaction of GSH with the vinyl-functionalized boron-dipyrromethene (4,4-difluoro-4-bora-3a,4a-diaza-s-indacene or BODIPY) 1. The probe was applied for real-time monitoring of the fluctuations in GSH levels in cells under cisplatin treatment. Notably, in cellular cisplatin-sensitive A549 cells, GSH concentrations rose until cell death, while in cisplatin-resistant cell lines, GSH levels first rose to the maximum then fell back to the initial concentration without significant apoptosis. These results indicate that different trends in GSH fluctuation can help distinguish cisplatin-resistant from cisplatin-sensitive cells. As such, this study has shown that probe 1 may potentially be used for real-time monitoring of intracellular GSH levels in response to therapeutics.

19.
Hum Vaccin Immunother ; 16(3): 664-672, 2020 03 03.
Article in English | MEDLINE | ID: mdl-31545125

ABSTRACT

Although respiratory syncytial virus (RSV) infection in infants and young children is a global public health issue, development of a safe RSV vaccine has been impeded by formalin-inactivated RSV-enhanced respiratory disease (ERD). In developing a safer yet effective RSV vaccine for children, a strategy to decrease over-reactive T cells and increase neutralizing anti-RSV antibodies should be considered. We previously demonstrated that adult mice immunized with RSV recombinant G protein plus low-dose Cyclosporine A (G+ CsA) could, upon subsequent RSV challenge, produce increased levels of antigen-specific T regulatory cells in lungs that overcame the ERD. Neutralizing anti-RSV antibodies that prevented viral infection were also elicited. In this study, we investigated if such a G+ CsA vaccine could provide infant mice with the same protection from RSV infection without ERD. The results showed that the G+ CsA vaccine could prevent RSV infection with only a mild loss of body weight. Importantly, there was nearly normal morphology and no mucus appearance in lung tissues after RSV challenge. These results demonstrate that the G+ CsA vaccine strategy achieved similar benefits in the neonatal prime and infancy boost model as in the adult mouse model. The G+ CsA immunization strategy is potentially safe and effective in neonates and infants because it suppresses the devastating ERD.


Subject(s)
Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus Vaccines , Animals , Antibodies, Neutralizing , Antibodies, Viral , Immunity , Lung , Mice , Mice, Inbred BALB C , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Viruses
20.
Inorg Chem ; 58(19): 13150-13160, 2019 Oct 07.
Article in English | MEDLINE | ID: mdl-31539237

ABSTRACT

Mitochondrial DNA (mtDNA) is an attractive cellular target for anticancer agents in addition to nuclear DNA (nDNA). The cationic platinum(II) complex cis-[Pt(NP)(NH3)2Cl]NO3 (PtNP, NP = N-(2-ethylpyridine)-1,8-naphthalimide) bearing the DNA-intercalating moiety NP was designed. The structure of PtNP was fully characterized by single-crystal X-ray crystallography, NMR, and HRMS. PtNP is superior to cisplatin in both in vitro and in vivo anticancer activities with low systemic toxicity. The interaction of PtNP with CT-DNA demonstrated that PtNP could effectively bind to DNA through both covalent and noncovalent double binding modes. In addition to causing significant damage to nDNA and remarkable inhibition to DNA damage repair, PtNP also distributed in mitochondria, inducing mtDNA damage and affecting the downstream transcriptional level of mitochondrion-encoded genes. In addition, PtNP disturbed the physiological processes of mitochondria by reducing the mitochondrial membrane potential and promoting the generation of reactive oxygen species. Mechanistic studies demonstrate that PtNP induced apoptosis via mitochondrial pathways by upregulating Bax and Puma and downregulating Bcl-2 proteins, leading to the release of cytochrome c and activation of caspase-3 and caspase-9. As a dual-DNA-damage agent, PtNP is able to improve the anticancer activity by damaging both nuclear and mitochondrial DNA, thus providing a new anticancer mechanism of action for the naphthalimide monofunctional platinum(II) complexes.


Subject(s)
Antineoplastic Agents/pharmacology , DNA Damage/drug effects , Intercalating Agents/pharmacology , Organoplatinum Compounds/pharmacology , Animals , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Line, Tumor , Crystallography, X-Ray , Humans , Intercalating Agents/chemistry , Membrane Potential, Mitochondrial/drug effects , Mice, Inbred ICR , Models, Molecular , Naphthalimides/chemistry , Naphthalimides/pharmacology , Neoplasms/drug therapy , Neoplasms/genetics , Organoplatinum Compounds/chemistry , Pyridines/chemistry , Pyridines/pharmacology
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