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1.
Chem Sci ; 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39355226

RESUMEN

Facile immobilization is essential for the wide application of enzymes in large-scale catalytic processes. However, exploration of suitable enzyme supports poses an unmet challenge, particularly in the context of scale-up biocatalyst fabrication. In this study, we present facile and scale-up syntheses of high-performance enzyme biocatalysts via in situ encapsulation of cytochrome c (Cyt-c) as mono-enzyme and glucose oxidase (GOx)-horseradish peroxidase (HRP) as dual-enzyme cascade (GOx&HRP) systems, respectively, into a stable mesoporous hydrogen-bonded organic framework (meso-HOF) matrix. In situ encapsulation reactions occur under ambient conditions, and facilitate scale up (∼3 g per reaction) of enzyme@meso-HOF within a very short period (5-10 min). The resultant biocatalysts not only exhibit high enzyme loading (37.9 wt% for mono-enzyme and 22.8 wt% for dual-enzyme) with minimal leaching, but also demonstrate high catalytic activity, superior reusability, and durability. This study represents an example of scale-up fabrication of enzyme@meso-HOF biocatalysts on the gram level and highlights superior meso-HOFs as suitable host matrices for biomolecular entities.

2.
J Nanobiotechnology ; 22(1): 587, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39342211

RESUMEN

Spatiotemporally controlled cargo release is a key advantage of nanocarriers in anti-tumor therapy. Various external or internal stimuli-responsive nanomedicines have been reported for their ability to increase drug levels at the diseased site and enhance therapeutic efficacy through a triggered release mechanism. Redox-manipulating nanocarriers, by exploiting the redox imbalances in tumor tissues, can achieve precise drug release, enhancing therapeutic efficacy while minimizing damage to healthy cells. As a typical redox-sensitive bond, the disulfide bond is considered a promising tool for designing tumor-specific, stimulus-responsive drug delivery systems (DDS). The intracellular redox imbalance caused by tumor microenvironment (TME) regulation has emerged as an appealing therapeutic target for cancer treatment. Sustained glutathione (GSH) depletion in the TME by redox-manipulating nanocarriers can exacerbate oxidative stress through the exchange of disulfide-thiol bonds, thereby enhancing the efficacy of ROS-based cancer therapy. Intriguingly, GSH depletion is simultaneously associated with glutathione peroxidase 4 (GPX4) inhibition and dihydrolipoamide S-acetyltransferase (DLAT) oligomerization, triggering mechanisms such as ferroptosis and cuproptosis, which increase the sensitivity of tumor cells. Hence, in this review, we present a comprehensive summary of the advances in disulfide based redox-manipulating nanocarriers for anticancer drug delivery and provide an overview of some representative achievements for combinational therapy and theragnostic. The high concentration of GSH in the TME enables the engineering of redox-responsive nanocarriers for GSH-triggered on-demand drug delivery, which relies on the thiol-disulfide exchange reaction between GSH and disulfide-containing vehicles. Conversely, redox-manipulating nanocarriers can deplete GSH, thereby enhancing the efficacy of ROS-based treatment nanoplatforms. In brief, we summarize the up-to-date developments of the redox-manipulating nanocarriers for cancer therapy based on DDS and provide viewpoints for the establishment of more stringent anti-tumor nanoplatform.


Asunto(s)
Antineoplásicos , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Nanopartículas , Neoplasias , Oxidación-Reducción , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Portadores de Fármacos/química , Animales , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/tratamiento farmacológico , Nanopartículas/química , Microambiente Tumoral/efectos de los fármacos , Glutatión/metabolismo , Glutatión/química , Disulfuros/química , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo/efectos de los fármacos , Liberación de Fármacos
3.
Nat Metab ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322747

RESUMEN

The crucial role of gut microbiota in shaping immunotherapy outcomes has prompted investigations into potential modulators. Here we show that oral administration of acarbose significantly increases the anti-tumour response to anti-PD-1 therapy in female tumour-bearing mice. Acarbose modulates the gut microbiota composition and tryptophan metabolism, thereby contributing to changes in chemokine expression and increased T cell infiltration within tumours. We identify CD8+ T cells as pivotal components determining the efficacy of the combined therapy. Further experiments reveal that acarbose promotes CD8+ T cell recruitment through the CXCL10-CXCR3 pathway. Faecal microbiota transplantation and gut microbiota depletion assays indicate that the effects of acarbose are dependent on the gut microbiota. Specifically, acarbose enhances the efficacy of anti-PD-1 therapy via the tryptophan catabolite indoleacetate, which promotes CXCL10 expression and thus facilitates CD8+ T cell recruitment, sensitizing tumours to anti-PD-1 therapy. The bacterial species Bifidobacterium infantis, which is enriched by acarbose, also improves response to anti-PD-1 therapy. Together, our study endorses the potential combination of acarbose and anti-PD-1 for cancer immunotherapy.

4.
Biomaterials ; 314: 122820, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39277948

RESUMEN

Ferroptosis has been recognized as a promising therapeutic strategy for cancer due to its unique mechanism of action. However, the upregulation of stearoyl-CoA desaturase 1 (SCD1) in ovarian cancer leads to resistance to ferroptotic therapy. Zinc ion (Zn2+) serves as the cofactor of SCD1. It was hypothesized that selective deprivation of Zn2+ from SCD1 could sensitize ferroptotic ovarian cancer therapy. Here, we report a hypoxia-responsive polymer micelle for enhanced ferroptosis of ovarian cancer cells. A SCD1 inhibitor, PluriSIn 1 (Plu), and a ferroptosis inducer, Auranofin (Aur), were co-encapsulated in nitroimidazole-bearing micelles. Under the hypoxic tumor microenvironment, the conversion of nitroimidazole to aminoimidazole triggered the cargo release and induced the depletion of antioxidant molecules (e.g., glutathione, thioredoxin, and NADPH). Meanwhile, because of the strong coordination between aminoimidazole and Zn2+ compared to that of histidine and Zn2+, such conversion can deprive the metal cofactor of SCD1, hence sensitizing the action of Plu and Aur. The proof-of-concept was demonstrated in cell and animal models with minimal systemic toxicity. The current work integrates ferroptosis induction with SCD1 inhibition in a hypoxia-responsive vehicle, offering a promising strategy for addressing the ferroptosis resistance and opening novel avenues for managing the difficult-to-treat ovarian cancer.

5.
Digit Health ; 10: 20552076241283338, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39291154

RESUMEN

Objective: Concerns regarding sleep problems in emerging adults and their antecedents, such as problematic smartphone use (PSU), have been growing. This study tested the association between PSU and sleep problems and further investigated the mechanisms of this relationship based on the theory of compensatory health beliefs (CHBs). Methods: This study included 999 participants (74.87% female) in China, aged 17 to 25 years (M = 21.16; standard deviation = 1.60), who voluntarily filled in an anonymous survey. Results: The findings showed positive correlations between sleep problems and PSU, sleep-related CHBs, and bedtime procrastination (rs = .25-.52, p < .001). Furthermore, the positive link between PSU and sleep problems was mediated by bedtime procrastination alone (ß=.21, 95% confidence interval (CI) [.17, .26]) or a serial path of sleep-related CHBs and bedtime procrastination (ß=.04, 95% CI [.02, .05]). Conclusion: This study provides a new perspective to understand the internal mechanism underlying the PSU-sleep problem link. Interventions for sleep disorders ought to consider the theoretical guidelines of the CHBs model to reduce the risk of bedtime procrastination and sleep disorders in emerging adults.

6.
Int J Mol Sci ; 25(18)2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39337596

RESUMEN

Perylenequinones (PQs) are important natural compounds that have been extensively utilized in recent years as agents for antimicrobial, anticancer, and antiviral photodynamic therapies. In this study, we investigated the molecular mechanisms regulating PQ biosynthesis by comparing Shiraia sp. Slf14 with its low PQ titer mutant, Slf14(w). The results indicated that the strain Slf14 exhibited a higher PQ yield, a more vigorous energy metabolism, and a more pronounced oxidation state compared to Slf14(w). Transcriptome analysis consistently revealed that the differences in gene expression between Slf14 and Slf14(w) are primarily associated with genes involved in redox processes and energy metabolism. Additionally, reactive oxygen species (ROS) were shown to play a crucial role in promoting PQ synthesis, as evidenced by the application of ROS-related inhibitors and promoters. Further results demonstrated that mitochondria are significant sources of ROS, which effectively regulate PQ biosynthesis in Shiraia sp. Slf14. In summary, this research revealed a noteworthy finding: the higher energy metabolism of the strain Slf14 is associated with increased intracellular ROS accumulation, which in turn triggers the activation and expression of gene clusters responsible for PQ synthesis.


Asunto(s)
Metabolismo Energético , Mitocondrias , Perileno , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Perileno/análogos & derivados , Perileno/metabolismo , Mitocondrias/metabolismo , Quinonas/metabolismo , Ascomicetos/metabolismo , Ascomicetos/genética , Regulación Fúngica de la Expresión Génica , Perfilación de la Expresión Génica
7.
Polymers (Basel) ; 16(16)2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39204578

RESUMEN

Microglia respond to stressors by secreting cytokines or growth factors, playing a crucial role in maintaining brain homeostasis. While the antidepressant-like effects of Polygonatum sibiricum polysaccharides (PSPs) have been observed in mice, their potential effectiveness involving microglial regulation remains unknown. This study investigates the antidepressant-like mechanism of PSP by regulating microglial phenotype and signaling pathways in the prefrontal cortex of chronic restraint stress (CRS)-induced mice. PSP was extracted, purified, characterized, and orally administered to CRS mice. High-performance gel permeation chromatography (HPGPC) revealed that PSP has a molecular weight of 5.6 kDa. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that PSP exhibited a layered structure with densely packed, irregular surfaces. PSP treatment significantly increased sucrose preference (low: 71%, p < 0.01; medium: 69%, p < 0.05; high: 75%, p < 0.001 vs. CRS: 58%) and reduced immobility time (low: 74 s, p < 0.01; medium: 68 s, p < 0.01; high: 79 s, p < 0.05 vs. CRS: 129 s), indicating the alleviation of depressive-like behaviors. PSP inhibited microglial activation (PSP, 131/mm2 vs. CRS, 173/mm2, p = 0.057), reversing CRS-induced microglial hypertrophy and hyper-ramification. Furthermore, PSP inactivated microglial activation by inhibiting NLRP3/ASC/caspase-1/IL-1ß signaling pathways, increasing BDNF synthesis and activating brain-derived neurotrophic factor (BDNF)-mediated neurogenesis (PSP, 80/per DG vs. CRS, 49/per DG, p < 0.01). In conclusion, PSP exerts antidepressant-like effects through the regulation of microglial activity and neuroinflammatory pathways, indicating it as a potential natural compound for depression treatment.

8.
World J Gastrointest Oncol ; 16(8): 3481-3495, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39171171

RESUMEN

BACKGROUND: Hepatic arterial infusion chemotherapy and camrelizumab plus apatinib (TRIPLET protocol) is promising for advanced hepatocellular carcinoma (Ad-HCC). However, the usefulness of microwave ablation (MWA) after TRIPLET is still controversial. AIM: To compare the efficacy and safety of TRIPLET alone (T-A) vs TRIPLET-MWA (T-M) for Ad-HCC. METHODS: From January 2018 to March 2022, 217 Ad-HCC patients were retrospectively enrolled. Among them, 122 were included in the T-A group, and 95 were included in the T-M group. A propensity score matching (PSM) was applied to balance bias. Overall survival (OS) was compared using the Kaplan-Meier curve with the log-rank test. The overall objective response rate (ORR) and major complications were also assessed. RESULTS: After PSM, 82 patients were included both the T-A group and the T-M group. The ORR (85.4%) in the T-M group was significantly higher than that (65.9%) in the T-A group (P < 0.001). The cumulative 1-, 2-, and 3-year OS rates were 98.7%, 93.4%, and 82.0% in the T-M group and 85.1%, 63.1%, and 55.0% in the T-A group (hazard ratio = 0.22; 95% confidence interval: 0.10-0.49; P < 0.001). The incidence of major complications was 4.9% (6/122) in the T-A group and 5.3% (5/95) in the T-M group, which were not significantly different (P = 1.000). CONCLUSION: T-M can provide better survival outcomes and comparable safety for Ad-HCC than T-A.

9.
Int J Ophthalmol ; 17(8): 1469-1476, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39156792

RESUMEN

AIM: To describe the multimodal imaging features, treatment, and outcomes of patients diagnosed with adult-onset Coats disease. METHODS: This retrospective study included patients first diagnosed with Coats disease at ≥18 years of age between September 2017 and September 2021. Some patients received anti-vascular endothelial growth factor (VEGF) therapy (conbercept, 0.5 mg) as the initial treatment, which was combined with laser photocoagulation as needed. All the patients underwent best corrected visual acuity (BCVA) and intraocular pressure examinations, fundus color photography, spontaneous fluorescence tests, fundus fluorescein angiography, optical coherence tomography (OCT), OCT angiography, and other examinations. BCVA alterations and multimodal image findings in the affected eyes following treatment were compared and the prognostic factors were analyzed. RESULTS: The study included 15 patients who were aged 24-72 (57.33±12.61)y at presentation. Systemic hypertension was the most common associated systemic condition, occurring in 13 (86.7%) patients. Baseline BCVA ranged from 2.0 to 5.0 (4.0±1.1), which showed improvement following treatment (4.2±1.0). Multimodal imaging revealed retinal telangiectasis in 13 patients (86.7%), patchy hemorrhage in 5 patients (33.3%), and stage 2B disease (Shield's staging criteria) in 11 patients (73.3%). OCT revealed that the baseline central macular thickness (CMT) ranged from 129 to 964 µm (473.0±230.1 µm), with 13 patients (86.7%) exhibiting a baseline CMT exceeding 250 µm. Furthermore, 8 patients (53.3%) presented with an epiretinal membrane at baseline or during follow-up. Hyper-reflective scars were observed on OCT in five patients (33.3%) with poor visual prognosis. Vision deteriorated in one patient who did not receive treatment. Final vision was stable in three patients who received laser treatment, whereas improvement was observed in one of two patients who received anti-VEGF therapy alone. In addition, 8 of 9 patients (88.9%) who received laser treatment and conbercept exhibited stable or improved BCVA. CONCLUSION: Multimodal imaging can help diagnose adult-onset Coats disease. Anti-VEGF treatment combined with laser therapy can be an option for improving or maintaining BCVA and resolving macular edema. The final visual outcome depends on macular involvement and the disease stage.

10.
Rev Sci Instrum ; 95(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39133090

RESUMEN

Medium-voltage (MV) switchgear and gas insulated switchgear (GIS) are essential components of power-grid systems. Their safe operation is crucial for the electricity consumption of users. However, insulation faults often occur during the operation of MV switchgear and GIS because of pollution, humidity, heat, mechanical shock, and other factors. Partial discharge (PD) measurements are the most effective indicator to prevent insulation failure. Transient earth voltage (TEV) and ultrasonic methods are the most popular PD measurement methods for switchgear. Currently, these two methods are used widely and independently. In this study, a novel TEV-ultrasonic integrated sensor is proposed based on the independent structure of the TEV and the ultrasonic sensor. The performance parameters of the proposed sensor were tested on test platforms. PD measurement experiments were conducted in a 10 kV switchgear and 220 kV GIS to analyze the performance of the integrated sensor. The results show that the sensor can simultaneously measure the TEV and ultrasonic signals in the same location. The integrated sensor can realize effective and sensitive detection, precise location, and accurate diagnosis of PD in the MV switchgear and GIS.

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