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1.
Biointerphases ; 19(4)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007691

RESUMO

Retinal degenerative diseases, which can lead to photoreceptor cell apoptosis, have now become the leading irreversible cause of blindness worldwide. In this study, we developed an organic photovoltaic biomaterial for artificial retinas, enabling neural cells to detect photoelectric stimulation. The biomaterial was prepared using a conjugated polymer donor, PCE-10, and a non-fullerene receptor, Y6, both known for their strong near-infrared light absorption capabilities. Additionally, a fullerene receptor, PC61BM, was incorporated, which possesses the ability to absorb reactive oxygen species. We conducted a comprehensive investigation into the microstructure, photovoltaic properties, and photothermal effects of this three-component photovoltaic biomaterial. Furthermore, we employed Rat adrenal pheochromocytoma cells (PC-12) as a standard neural cell model to evaluate the in vitro photoelectric stimulation effect of this photovoltaic biomaterial. The results demonstrate that the photovoltaic biomaterial, enriched with fullerene derivatives, can induce intracellular calcium influx in PC-12 cells under 630 nm (red light) and 780 nm (near-infrared) laser irradiation. Moreover, there were lower levels of oxidative stress and higher levels of mitochondrial activity compared to the non-PC61BM group. This photovoltaic biomaterial proves to be an ideal substrate for near-infrared photoelectrical stimulation of neural cells and holds promise for restoring visual function in patients with photoreceptor apoptosis.


Assuntos
Materiais Biocompatíveis , Fulerenos , Raios Infravermelhos , Animais , Fulerenos/química , Fulerenos/farmacologia , Ratos , Materiais Biocompatíveis/química , Células PC12 , Neurônios/efeitos dos fármacos , Neurônios/efeitos da radiação , Cálcio/metabolismo , Cálcio/química
2.
J Agric Food Chem ; 72(29): 16403-16411, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39004912

RESUMO

As a highly toxic mycotoxin, ochratoxin A (OTA) is widely contaminating agricultural products and has various toxicological effects. Bioenzymes for OTA degradation have shown promising potential for detoxification. Other than the efficient amidohydrolase ADH3 previously, two novel amidohydrolases ADH1 and AMD3 were obtained in this study. During Escherichia coli expression, the expressed protein solubility was very low and will limit future industrial application. Here, high copy number integrations were screened, and the amidohydrolases were efficiently secretory expressed by Pichia pastoris GS115. The protein yields from 1.0 L of fermentation supernatant were 53.5 mg for ADH1, 89.15 mg for ADH3, and 79.5 mg for AMD3. The catalytic efficiency (Kcat/Km) of secretory proteins was 124.95 s-1 mM-1 for ADH3, 123.21 s-1 mM-1 for ADH1, and 371.99 s-1 mM-1 for AMD3. In comparison to E. coli expression, the active protein yields substantially increased 15.78-51.53 times. Meanwhile, two novel amidohydrolases (ADH1 and AMD3) showed much higher activity than ADH3 that produced by secretory expression.


Assuntos
Amidoidrolases , Expressão Gênica , Ocratoxinas , Ocratoxinas/metabolismo , Ocratoxinas/química , Hidrólise , Amidoidrolases/genética , Amidoidrolases/metabolismo , Amidoidrolases/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Escherichia coli/genética , Escherichia coli/metabolismo , Saccharomycetales/genética , Saccharomycetales/enzimologia , Saccharomycetales/metabolismo , Cinética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Fermentação , Pichia/genética , Pichia/metabolismo
3.
J Hazard Mater ; 473: 134716, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38797074

RESUMO

Ochratoxin A (OTA) is a toxic secondary metabolite that widely contaminates agro-products and poses a significant dietary risk to human health. Previously, a carboxypeptidase CP4 was characterized for OTA degradation in Lysobacter sp. CW239, but the degradation activity was much lower than its host strain CW239. In this study, an amidohydrolase ADH2 was screened for OTA hydrolysis in this strain. The result showed that 50 µg/L OTA was completely degraded by 1.0 µg/mL rADH2 within 5 min, indicating ultra-efficient activity. Meanwhile, the two hydrolases (i.e., CP4 and ADH2) in the strain CW239 showed the same degradation manner, which transformed the OTA to ochratoxin α (OTα) and l-ß-phenylalanine. Gene mutants (Δcp4, Δadh2 and Δcp4-adh2) testing result showed that OTA was co-degraded by carboxypeptidase CP4 and amidohydrolase ADH2, and the two hydrolases are sole agents in strain CW239 for OTA degradation. Hereinto, the ADH2 was the overwhelming efficient hydrolase, and the two types of hydrolases co-degraded OTA in CW239 by synergistic effect. The results of this study are highly significant to ochratoxin A contamination control during agro-products production and postharvest.


Assuntos
Lysobacter , Ocratoxinas , Ocratoxinas/metabolismo , Ocratoxinas/toxicidade , Lysobacter/metabolismo , Lysobacter/genética , Amidoidrolases/metabolismo , Amidoidrolases/genética , Carboxipeptidases/metabolismo , Carboxipeptidases/genética , Hidrolases/metabolismo , Hidrolases/genética
4.
Ophthalmol Ther ; 13(7): 1967-1980, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38789667

RESUMO

INTRODUCTION: The aim of this work was to compare the prognosis and characteristics of patients with Cytomegalovirus (CMV) infection (CMV+) with those of patients without virus infection (Virus-) undergoing repeat keratoplasty. METHODS: This prospective propensity score-matched cohort study enrolled patients who underwent repeat keratoplasty for graft failure at the Peking University Third Hospital between January 2016 and May 2022. Patients with prior viral keratitis before the first keratoplasty were excluded. The primary outcome measure was the graft failure rate. The secondary outcome measures included the anterior segment characteristics, intraocular pressure (IOP), and endothelial cell density. RESULTS: Ninety-four matched patient pairs were included. The graft failure rate in the CMV+ group (71%) was higher than that in the Virus- group (29%) (P < 0.001). CMV infection in the cornea increased the risk of repeat graft failure and shortened the median survival time (hazard ratio, 3.876; 95% confidence intervals, 2.554-5.884; P < 0.001). The characteristics of graft failure included exacerbation of ocular surface inflammation, neovascularization, and opacification. Epithelial defects, high IOP, and endothelial decompensation were observed at an increased frequency in the CMV+ group (all P < 0.005). Recurrent CMV infection presented as early endothelial infection in the CMV+ group. Recurrence of CMV infection was confined to the graft endothelium without involving the stroma and epithelium post-repeat endothelial keratoplasty. CONCLUSIONS: CMV infection post-keratoplasty leads to persistent endothelial damage and graft opacification and significantly increases the risk of repeat graft failure. Localized recurrence of CMV infection in the endothelial grafts underscores the importance of monitoring and treatment. TRIAL REGISTRATION: Chictr.org.cn, ChiCTR1800014684.

5.
Angew Chem Int Ed Engl ; 63(29): e202402133, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-38708621

RESUMO

We describe small heterojunction polymer dots (Pdots) with deep-red light catalyzed H2 generation for diabetic skin wound healing. The Pdots with donor/acceptor heterojunctions showed remarkably enhanced photocatalytic activity as compared to the donor or acceptor nanoparticles alone. We encapsulate the Pdots and ascorbic acid into liposomes to form Lipo-Pdots nanoreactors, which selectively scavenge ⋅OH radicals in live cells and tissues under 650 nm light illumination. The antioxidant capacity of the heterojunction Pdots is ~10 times higher than that of the single-component Pdots described previously. Under a total light dose of 360 J/cm2, the Lipo-Pdots nanoreactors effectively scavenged ⋅OH radicals and suppressed the expression of pro-inflammatory cytokines in skin tissues, thereby accelerating the healing of skin wounds in diabetic mice. This study provides a feasible solution for safe and effective treatment of diabetic foot ulcers.


Assuntos
Diabetes Mellitus Experimental , Hidrogênio , Luz , Polímeros , Cicatrização , Cicatrização/efeitos dos fármacos , Hidrogênio/química , Animais , Camundongos , Polímeros/química , Humanos , Pontos Quânticos/química , Luz Vermelha
6.
Graefes Arch Clin Exp Ophthalmol ; 262(8): 2593-2600, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38446197

RESUMO

PURPOSE: To evaluate cytokine levels of aqueous humor in patients with cytomegalovirus (CMV) corneal endotheliitis and their relationships with CMV DNA load. METHODS: 44 aqueous humor samples were obtained from 26 patients with CMV corneal endotheliitis at various stages of treatment. 33 samples obtained from cataract patients during the same period were selected as a control group. Each sample was used to measure the concentration of the CMV DNA load using real-time quantitative polymerase chain reaction, and to examine the levels of IL-6, IL-8, IL-10, MCP-1, VCAM-1, VEGF, IP-10, G-CSF, ICAM-1 and IFN-γ using a cytometric bead array. RESULTS: All 10 cytokines were found to have statistically significant differences between the CMV endotheliitis and cataract groups. The Spearman correlation test showed that the concentration of CMV DNA load was significantly associated with the levels of IL-6 (P = 0.005, r = 0.417), IL-8 (P < 0.001, r = 0.514), IL-10 (P < 0.001, r = 0.700), MCP-1 (P = 0.001, r = 0.487), VEGF (P < 0.001, r = 0.690), IP-10 (P = 0.001, r = 0.469), G-CSF (P < 0.001, r = 0.554) and ICAM-1 (P < 0.001, r = 0.635), but not significantly associated with VCAM-1 (P = 0.056) and IFN-γ (P = 0.219). CONCLUSIONS: There was a combined innate and adaptive immune response in aqueous humor in patients with CMV endotheliitis. Levels of multiple cytokines were significantly correlated with viral particle. Cytokines are potential indicators to help diagnose CMV endotheliitis, evaluate disease activity and assess treatment response.


Assuntos
Humor Aquoso , Citocinas , Infecções por Citomegalovirus , Citomegalovirus , DNA Viral , Endotélio Corneano , Infecções Oculares Virais , Humanos , Humor Aquoso/virologia , Humor Aquoso/metabolismo , Masculino , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/tratamento farmacológico , Feminino , Citocinas/metabolismo , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Endotélio Corneano/virologia , Endotélio Corneano/metabolismo , Endotélio Corneano/patologia , Infecções Oculares Virais/virologia , Infecções Oculares Virais/diagnóstico , Infecções Oculares Virais/metabolismo , Infecções Oculares Virais/tratamento farmacológico , Pessoa de Meia-Idade , Idoso , DNA Viral/análise , Ceratite/virologia , Ceratite/diagnóstico , Ceratite/metabolismo , Adulto , Reação em Cadeia da Polimerase em Tempo Real
8.
Small ; 20(25): e2310342, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38221682

RESUMO

Ferroptosis is a new form of regulated cell death featuring iron-dependent lipid peroxides accumulation to kill tumor cells. A growing body of evidence has shown the potential of ferroptosis-based cancer therapy in eradicating refractory malignancies that are resistant to apoptosis-based conventional therapies. In recent years, studies have reported a number of ferroptosis inducers that can increase the vulnerability of tumor cells to ferroptosis by regulating ferroptosis-related signaling pathways. Encouraged by the rapid development of ferroptosis-driven cancer therapies, interdisciplinary fields that combine ferroptosis, pharmaceutical chemistry, and nanotechnology are focused. First, the prerequisites and metabolic pathways for ferroptosis are briefly introduced. Then, in detail emerging ferroptosis inducers designed to boost ferroptosis-induced tumor therapy, including metal complexes, metal-based nanoparticles, and metal-free nanoparticles are summarized. Subsequently, the application of synergistic strategies that combine ferroptosis with apoptosis and other regulated cell death for cancer therapy, with emphasis on the use of both cuproptosis and ferroptosis to induce redox dysregulation in tumor and intracellular bimetallic copper/iron metabolism disorders during tumor treatment is discussed. Finally, challenges associated with clinical translation and potential future directions for potentiating cancer ferroptosis therapies are highlighted.


Assuntos
Ferroptose , Nanomedicina , Neoplasias , Ferroptose/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Nanomedicina/métodos , Animais , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico
9.
Nat Commun ; 15(1): 170, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167652

RESUMO

Practical photodynamic therapy calls for high-performance, less O2-dependent, long-wavelength-light-activated photosensitizers to suit the hypoxic tumor microenvironment. Iridium-based photosensitizers exhibit excellent photocatalytic performance, but the in vivo applications are hindered by conventional O2-dependent Type-II photochemistry and poor absorption. Here we show a general metallopolymerization strategy for engineering iridium complexes exhibiting Type-I photochemistry and enhancing absorption intensity in the blue to near-infrared region. Reactive oxygen species generation of metallopolymer Ir-P1, where the iridium atom is covalently coupled to the polymer backbone, is over 80 times higher than that of its mother polymer without iridium under 680 nm irradiation. This strategy also works effectively when the iridium atom is directly included (Ir-P2) in the polymer backbones, exhibiting wide generality. The metallopolymer nanoparticles exhibiting efficient O2•- generation are conjugated with integrin αvß3 binding cRGD to achieve targeted photodynamic therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/química , Irídio/química , Hipóxia/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Polímeros/uso terapêutico , Microambiente Tumoral
10.
Adv Mater ; 36(2): e2305361, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37699593

RESUMO

The cancer-immune cycle conceptualized the mechanisms of driving T cell responses to tumors, but w as limited by immunological ignorance elicited by tumor inherent immunoediting, which failed to initiate and maintain adaptive immunity. Targeting specific vulnerabilities of cell death patterns may provide unique opportunities to boost T cell antitumor immunological effects. Here an ultrasound nanomedicine-triggered tumor immuno-reediting therapeutic strategy using nano/genetically engineered extracellular vesicles, which can induce tumor highly immunogenic PANoptosis and iteratively start-up the energization of cancer innate immunity cycle by repeatedly liberating damage-associated molecular patterns, thereby priming sufficient antigen-specific T cells and shaping protective immune response through activating cGAS-STING signaling pathways, is reported. Aided by immune checkpoint blockade, the reprogramming of immune microenvironment further facilitated a prompt bridging of innate and adaptive immunity, and remarkably suppressed metastatic and rechallenged tumor growth. Thus, targeting PANoptotic cell death provides a catcher against immune escape and a positive-feedback immune activation gateway for overcoming immune resistance to intractable cancers.


Assuntos
Neoplasias , Humanos , Neoplasias/terapia , Linfócitos T , Imunidade Inata , Imunidade Adaptativa , Antígenos de Neoplasias , Microambiente Tumoral , Imunoterapia
11.
Adv Colloid Interface Sci ; 322: 103037, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37931381

RESUMO

Inspired by natural catalytic compartments, various synthetic compartments that seclude catalytic reactions have been developed to understand complex multistep biosynthetic pathways, bestow therapeutic effects, or extend biosynthetic pathways in living cells. These emerging nanoreactors possessed many advantages over conventional biomedicine, such as good catalytic activity, specificity, and sustainability. In the past decade, a great number of efficient catalytic systems based on diverse nanoreactors (polymer vesicles, liposome, polymer micelles, inorganic-organic hybrid materials, MOFs, etc.) have been designed and employed to initiate in situ catalyzed chemical reactions for therapy. This review aims to present the recent progress in the development of catalytic systems based on nanoreactors for therapeutic applications, with a special emphasis on the principles and design strategies. Besides, the key components of nanoreactor-based catalytic systems, including nanocarriers, triggers or energy inputs, and products, are respectively introduced and discussed in detail. Challenges and prospects in the fabrication of therapeutic catalytic nanoreactors are also discussed as a conclusion to this review. We believe that catalytic nanoreactors will play an increasingly important role in modern biomedicine, with improved therapeutic performance and minimal side effects.


Assuntos
Lipossomos , Polímeros , Catálise , Micelas , Nanotecnologia
12.
Front Oncol ; 13: 1216894, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37645433

RESUMO

Purpose: Our aim was to conduct a meta-analysis and systematic review in order to compare the diagnostic efficacy of 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI in patients with biochemically recurrent after radical prostatectomy and biochemically recurrent prostate cancers (BCR) after hybrid RT and RP. Methods: Up until February 2023, we searched PubMed, Embase, and Web of Science for pertinent papers. Studies examining the utility of 68Ga-PSMA-11 PET/CT or PET/MRI as a screening tool for biochemically recurrent prostate cancer were included. To measure heterogeneity, we employed the I2 statistic. In cases of substantial heterogeneity (I2 > 50%), we used the random effect model to produce a forest plot. In other cases, we utilized the fixed model. Furthermore, we assessed the quality of the studies included using the Quality Assessment of Diagnostic Performance Studies (QUADAS-2) method. Results: In total, 37 studies involving 8409 patients were examined. For 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI, the combined total detection rate was 0.70 (95% CI: 0.65-0.75) and 0.71 (95% CI:0.67-0.75), respectively. 68Ga-PSMA-11 PET/CT and 68Ga-PSMA-11 PET/MRI did not substantially differ in terms of the overall detection rate for BCR (P = 0.58). The detection rate was unaffected by the PSA values (all P > 0.05). Conclusion: The diagnostic efficacy of 68Ga-PSMA-11 PET/CT appears to be equivalent to that of 68Ga-PSMA-11 PET/MRI in detecting biochemically recurrent prostate cancer. Nonetheless, it should be noted that not all studies have used pathological biopsies as the gold standard. Therefore, additional larger prospective studies are needed to address this issue. Systematic review registration: identifier CRD42023410039.

13.
J Am Chem Soc ; 145(24): 13099-13113, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37216494

RESUMO

Photosensitizers to precise target and change fluorescence upon light illumination could accurately self-report where and when the photosensitizers work, enabling us to visualize the therapeutic process and precisely regulate treatment outcomes, which is the unremitting pursuit of precision and personalized medicine. Here, we report self-immolative photosensitizers by adopting a strategy of light-manipulated oxidative cleavage of C═C bonds that can generate a burst of reactive oxygen species, to cleave to release self-reported red-emitting products and trigger nonapoptotic cell oncosis. Strong electron-withdrawing groups are found to effectively suppress the C═C bond cleavage and phototoxicity via studying the structure-activity relationship, allowing us to elaborate NG1-NG5 that could temporarily inactivate the photosensitizer and quench the fluorescence by different glutathione (GSH)-responsive groups. Thereinto, NG2 with 2-cyano-4-nitrobenzene-1-sulfonyl group displays excellent GSH responsiveness than the other four. Surprisingly, NG2 shows better reactivity with GSH in weakly acidic condition, which inspires the application in weakly acidic tumor microenvironment where GSH elevates. To this end, we further synthesize NG-cRGD by anchoring integrin αvß3 binding cyclic pentapeptide (cRGD) for tumor targeting. In A549 xenografted tumor mice, NG-cRGD successfully deprotects to restore near-infrared fluorescence because of elevated GSH in tumor site, which is subsequently cleaved upon light irradiation releasing red-emitting products to report photosensitizer working, while effectively ablating tumors via triggered oncosis. The advanced self-immolative organic photosensitizer may accelerate the development of self-reported phototheranostics in future precision oncology.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Camundongos , Animais , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/química , Neoplasias/tratamento farmacológico , Autorrelato , Medicina de Precisão , Glutationa/química , Linhagem Celular Tumoral , Nanopartículas/química , Microambiente Tumoral
14.
RSC Adv ; 13(22): 15121-15125, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37223645

RESUMO

Semiconducting polymer dots (Pdots) with both narrow-band absorption and emission are desirable for multiplexed bioassay applications, but such Pdots with absorption peaks beyond 400 nm are difficult to achieve. Here we describe a donor-energy transfer unit-acceptor (D-ETU-A) design strategy to produce a BODIPY-based Pdot that exhibits simultaneously narrow absorption and emission bands. A green BODIPY (GBDP) unit was employed as the main building block of the polymer backbone, conferring a strong, narrow-band absorption around 551 nm. An NIR720 acceptor provides narrow-band NIR emission. The small Stokes shift of the GBDP donor allows introduction of a benzofurazan-based ETU, resulting in a ternary Pdot with a fluorescence quantum yield of 23.2%, the most efficient yellow-laser excitable Pdot. Due to the strong absorbance band centered at 551 nm and weak absorbance at 405 nm and 488 nm, the Pdot showed high single-particle brightness when excited by a 561 nm (yellow) laser, and selective yellow laser excitation when used to label MCF cells, with much greater brightness when excited at 561 nm than at 405 nm or 488 nm.

15.
Cancer Res ; 83(15): 2614-2633, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37227919

RESUMO

Cancer metastasis is an extremely complex process affected by many factors. An acidic microenvironment can drive cancer cell migration toward blood vessels while also hampering immune cell activity. Here, we identified a mechanism mediated by sialyltransferases that induces an acidic tumor-permissive microenvironment (ATPME) in BRCA1-mutant and most BRCA1-low breast cancers. Hypersialylation mediated by ST8SIA4 perturbed the mammary epithelial bilayer structure and generated an ATPME and immunosuppressive microenvironment with increased PD-L1 and PD1 expressions. Mechanistically, BRCA1 deficiency increased expression of VEGFA and IL6 to activate TGFß-ST8SIA4 signaling. High levels of ST8SIA4 led to accumulation of polysialic acid (PSA) on mammary epithelial membranes that facilitated escape of cancer cells from immunosurveillance, promoting metastasis and resistance to αPD1 treatment. The sialyltransferase inhibitor 3Fax-Peracetyl Neu5Ac neutralized the ATPME, sensitized cancers to immune checkpoint blockade by activating CD8 T cells, and inhibited tumor growth and metastasis. Together, these findings identify a potential therapeutic option for cancers with a high level of PSA. SIGNIFICANCE: BRCA1 deficiency generates an acidic microenvironment to promote cancer metastasis and immunotherapy resistance that can be reversed using a sialyltransferase inhibitor.


Assuntos
Neoplasias da Mama , Microambiente Tumoral , Humanos , Feminino , Imunoterapia , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Sialiltransferases/genética , Linhagem Celular Tumoral , Proteína BRCA1/genética
16.
Nat Commun ; 14(1): 1901, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019894

RESUMO

In contrast to the conventional passive reaction to analytes, here, we create a proof-of-concept nanochannel system capable of on-demand recognition of the target to achieve an unbiased response. Inspired by light-activatable biological channelrhodopsin-2, photochromic spiropyran/anodic aluminium oxide nanochannel sensors are constructed to realize a light-controlled inert/active-switchable response to SO2 by ionic transport behaviour. We find that light can finely regulate the reactivity of the nanochannels for the on-demand detection of SO2. Pristine spiropyran/anodic aluminium oxide nanochannels are not reactive to SO2. After ultraviolet irradiation of the nanochannels, spiropyran isomerizes to merocyanine with a carbon‒carbon double bond nucleophilic site, which can react with SO2 to generate a new hydrophilic adduct. Benefiting from increasing asymmetric wettability, the proposed device exhibits a robust photoactivated detection performance in SO2 detection in the range from 10 nM to 1 mM achieved by monitoring the rectified current.

17.
ACS Appl Mater Interfaces ; 15(9): 11575-11585, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36808954

RESUMO

Chemodynamic therapy (CDT) based on the Fe2+-mediated Fenton reaction can amplify intracellular oxidative stress by producing toxic •OH. However, the high-dose need for Fe2+ delivery in tumors and its significant cytotoxicity to normal tissues set a challenge. Therefore, a controllable delivery to activate the Fenton reaction and enhance Fe2+ tumor accumulation has become an approach to solve this conflict. Herein, we report a rare-earth-nanocrystal (RENC)-based Fe2+ delivery system using light-control techniques and DNA nanotechnology to realize programmable Fe2+ delivery. Ferrocenes, the source of Fe2+, are modified on the surface of RENCs through pH-responsive DNAs, which are further shielded by a PEG layer to elongate blood circulation and "turn off" the cytotoxicity of ferrocene. The up-/down-conversion dual-mode emissions of RENCs endow the delivery system with both capabilities of diagnosis and delivery control. The down-conversion NIR-II fluorescence can locate tumors. Consequently, up-conversion UV light spatiotemporally activates the catalytic activity of Fe2+ by shedding off the protective PEG layer. The exposed ferrocene-DNAs not only can "turn on" Fenton catalytic activity but also respond to tumor acidity, driving cross-linking and enhanced Fe2+ enrichment in tumors by 4.5-fold. Accordingly, this novel design concept will be inspiring for developing CDT nanomedicines in the future.


Assuntos
Metais Terras Raras , Nanopartículas , Neoplasias , Humanos , Luminescência , Fluorescência , Metalocenos , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Peróxido de Hidrogênio , Microambiente Tumoral
18.
Adv Healthc Mater ; 12(6): e2202663, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36653312

RESUMO

Ferroptosis, characterized by the accumulation of reactive oxygen species and lipid peroxides, has emerged as an attractive strategy to reverse drug resistance. Of particular interest is the ferroptosis-apoptosis combination therapy for cancer treatment. Herein, a nanoplatform is reported for effective co-delivery of the anticancer drug sorafenib (S) and the ferroptosis inducer hemin (H), toward synergistic ferroptosis-apoptosis therapy of advanced hepatocellular carcinoma (HCC) as a proof-of-concept study. Liposome is an excellent delivery system; however, it is not sufficiently responsive to the acidic tumor microenvironment (TME) for tumor-targeted drug delivery. The pH-sensitive vesicles are therefore developed (SH-AD-L) by incorporating amphiphilic dendrimers (AD) into liposomes for controlled and pH-stimulated release of sorafenib and hemin in the acidic TME, thanks to the protonation of numerous amine functionalities in AD. Importantly, SH-AD-L not only blocked glutathione synthesis to disrupt the antioxidant system, but also increased intracellular Fe2+ and ·OH concentrations to amplify oxidative stress, both of which contribute to enhanced ferroptosis. Remarkably, high levels of ·OH also augmented sorafenib-mediated apoptosis in tumor cells. This study demonstrates the efficacy of ferroptosis-apoptosis combination therapy, as well as the promise of the AD-doped TME-responsive vesicles for drug delivery in combination therapy to treat advanced HCC.


Assuntos
Carcinoma Hepatocelular , Dendrímeros , Ferroptose , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Sorafenibe/farmacologia , Sorafenibe/uso terapêutico , Dendrímeros/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Hemina/farmacologia , Hemina/uso terapêutico , Apoptose , Lipossomos/farmacologia , Polímeros/farmacologia , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral , Microambiente Tumoral
19.
Bioact Mater ; 24: 26-36, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36582345

RESUMO

Ultrasound (US)-activated sonodynamic therapy (SDT) stands for a distinct antitumor modality because of its attractive characteristics including intriguing noninvasiveness, desirable safety, and high tissue penetration depth, which, unfortunately, suffers from compromised therapeutic efficacy due to cancer cell-inherent adaptive mechanisms, such as glutathione (GSH) neutralization response to reactive oxygen species (ROS), and glutamine addictive properties of tumors. In this work, we developed a biological sonosensitive platelet (PLT) pharmacytes for favoring US/GSH-responsive combinational therapeutic of glutamine deprivation and augmented SDT. The amino acid transporter SLC6A14 blockade agent α-methyl-DL-tryptophan (α-MT)-loaded and MnO2-coated porphyrinic metal-organic framework (MOF) nanoparticles were encapsulated in the PLTs through the physical adsorption of electrostatic attraction and the intrinsic endocytosis of PLTs. When the sonosensitive PLT pharmacytes reached tumor sites through their natural tendencies to TME, US stimulated the PLTs-loaded porphyrinic MOF to generate ROS, resulting in morphological changes of the PLTs and the release of nanoparticles. Subsequently, intracellular high concentration of GSH and extracellular spatio-temporal controlled US irradiation programmatically triggered the release of α-MT, which enabled the synergistically amplified SDT by inducing amino acid starvation, inhibiting mTOR, and mediating ferroptosis. In addition, US stimulation achieved the targeted activation of PLTs at tumor vascular site, which evolved from circulating PLTs to dendritic PLTs, effectively blocking the blood supply of tumors through thrombus formation, and revealing the encouraging potential to facilitate tumor therapeutics.

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