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1.
Bioconjug Chem ; 35(7): 1015-1023, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38904455

RESUMO

Currently, clinical therapeutic strategies for nasopharyngeal carcinoma (NPC) confront insurmountable dilemmas in which surgical resection is incomplete and chemotherapy/radiotherapy has significant side effects. Phototherapy offers a maneuverable, effective, and noninvasive pattern for NPC therapy. Herein, we developed a lysosome-targeted and pH-responsive nanophototheranostic for near-infrared II (NIR-II) fluorescence imaging-guided photodynamic therapy (PDT) and photothermal therapy (PTT) of NPC. A lysosome-targeted S-D-A-D-S-type NIR-II phototheranostic molecule (IRFEM) is encapsulated within the acid-sensitive amphiphilic DSPE-Hyd-PEG2k to form IRFEM@DHP nanoparticles (NPs). The prepared IRFEM@DHP exhibits a good accumulation in the acidic lysosomes for facilitating the release of IRFEM, which could disrupt lysosomal function by generating an amount of heat and ROS under laser irradiation. Moreover, the guidelines of NIR-II fluorescence enhance the accuracy of PTT/PDT for NPC and avoid damage to normal tissues. Remarkably, IRFEM@DHP enable efficient antitumor effects both in vitro and in vivo, opening up a new avenue for precise NPC theranostics.


Assuntos
Lisossomos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Imagem Óptica , Nanomedicina Teranóstica , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/diagnóstico por imagem , Humanos , Lisossomos/metabolismo , Concentração de Íons de Hidrogênio , Nanomedicina Teranóstica/métodos , Animais , Imagem Óptica/métodos , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Camundongos , Raios Infravermelhos , Fototerapia/métodos , Linhagem Celular Tumoral , Nanopartículas/química , Fotoquimioterapia/métodos , Camundongos Nus , Camundongos Endogâmicos BALB C
2.
Mol Biol Cell ; 35(5): ar72, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568782

RESUMO

Cilia generate three-dimensional waveforms required for cell motility and transport of fluid, mucus, and particles over the cell surface. This movement is driven by multiple dynein motors attached to nine outer doublet microtubules that form the axoneme. The outer and inner arm dyneins are organized into 96-nm repeats tandemly arrayed along the length of the doublets. Motility is regulated in part by projections from the two central pair microtubules that contact radial spokes located near the base of the inner dynein arms in each repeat. Although much is known about the structures and protein complexes within the axoneme, many questions remain about the regulatory mechanisms that allow the cilia to modify their waveforms in response to internal or external stimuli. Here, we used Chlamydomonas mbo (move backwards only) mutants with altered waveforms to identify at least two conserved proteins, MBO2/CCDC146 and FAP58/CCDC147, that form part of a L-shaped structure that varies between doublet microtubules. Comparative proteomics identified additional missing proteins that are altered in other motility mutants, revealing overlapping protein defects. Cryo-electron tomography and epitope tagging revealed that the L-shaped, MBO2/FAP58 structure interconnects inner dynein arms with multiple regulatory complexes, consistent with its function in modifying the ciliary waveform.


Assuntos
Axonema , Dineínas , Axonema/metabolismo , Dineínas/metabolismo , Microtúbulos/metabolismo , Cílios/metabolismo , Proteínas/metabolismo , Flagelos/metabolismo
3.
Front Physiol ; 15: 1293380, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38426204

RESUMO

Background and Purpose: Precisely assessing the likelihood of an intracranial aneurysm rupturing is critical for guiding clinical decision-making. The objective of this study is to construct and validate a deep learning framework utilizing point clouds to forecast the likelihood of aneurysm rupturing. Methods: The dataset included in this study consisted of a total of 623 aneurysms, with 211 of them classified as ruptured and 412 as unruptured, which were obtained from two separate projects within the AneuX morphology database. The HUG project, which included 124 ruptured aneurysms and 340 unruptured aneurysms, was used to train and internally validate the model. For external validation, another project named @neurIST was used, which included 87 ruptured and 72 unruptured aneurysms. A standardized method was employed to isolate aneurysms and a segment of their parent vessels from the original 3D vessel models. These models were then converted into a point cloud format using open3d package to facilitate training of the deep learning network. The PointNet++ architecture was utilized to process the models and generate risk scores through a softmax layer. Finally, two models, the dome and cut1 model, were established and then subjected to a comprehensive comparison of statistical indices with the LASSO regression model built by the dataset authors. Results: The cut1 model outperformed the dome model in the 5-fold cross-validation, with the mean AUC values of 0.85 and 0.81, respectively. Furthermore, the cut1 model beat the morphology-based LASSO regression model with an AUC of 0.82. However, as the original dataset authors stated, we observed potential generalizability concerns when applying trained models to datasets with different selection biases. Nevertheless, our method outperformed the LASSO regression model in terms of generalizability, with an AUC of 0.71 versus 0.67. Conclusion: The point cloud, as a 3D visualization technique for intracranial aneurysms, can effectively capture the spatial contour and morphological aspects of aneurysms. More structural features between the aneurysm and its parent vessels can be exposed by keeping a portion of the parent vessels, enhancing the model's performance. The point cloud-based deep learning model exhibited good performance in predicting rupture risk while also facing challenges in generalizability.

4.
Hypertension ; 81(3): 582-594, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38174565

RESUMO

BACKGROUND: Clinical evidence revealed abnormal prevalence of coronary artery (CA) disease in patients with pulmonary hypertension (PH). The mechanistic connection between PH and CA disease is unclear. Serotonin (5-hydroxytryptamine), reactive oxygen species, and Ca2+ signaling have been implicated in both PH and CA disease. Our recent study indicates that NOXs (NADPH [nicotinamide adenine dinucleotide phosphate] oxidases) and TRPM2 (transient receptor potential cation channel subfamily M member 2) are key components of their interplay. We hypothesize that activation of the NOX-TRPM2 pathway facilitates the remodeling of CA in PH. METHODS: Left and right CAs from chronic hypoxia and monocrotaline-induced PH rats were collected to study vascular reactivity, gene expression, metabolism, and mitochondrial function. Inhibitors or specific siRNA were used to examine the pathological functions of NOX1/4-TRPM2 in CA smooth muscle cells. RESULTS: Significant CA remodeling and 5-hydroxytryptamine hyperreactivity in the right CA were observed in PH rats. NOX1/4-mediated reactive oxygen species production coupled with TRPM2-mediated Ca2+ influx contributed to 5-hydroxytryptamine hyperresponsiveness. CA smooth muscle cells from chronic hypoxia-PH rats exhibited increased proliferation, migration, apoptosis, and metabolic reprogramming in an NOX1/4-TRPM2-dependent manner. Furthermore, the NOX1/4-TRPM2 pathway participated in mitochondrial dysfunction, involving mitochondrial DNA damage, reactive oxygen species production, elevated mitochondrial membrane potential, mitochondrial Ca2+ accumulation, and mitochondrial fission. In vivo knockdown of NOX1/4 alleviated PH and suppressed CA remodeling in chronic hypoxia rats. CONCLUSIONS: PH triggers an increase in 5-hydroxytryptamine reactivity in the right CA and provokes metabolic reprogramming and mitochondrial disruption in CA smooth muscle cells via NOX1/4-TRPM2 activation. This signaling pathway may play an important role in CA remodeling and CA disease in PH.


Assuntos
Hipertensão Pulmonar , Canais de Cátion TRPM , Humanos , Ratos , Animais , Hipertensão Pulmonar/metabolismo , Serotonina/farmacologia , Serotonina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vasos Coronários/patologia , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Reprogramação Metabólica , Transdução de Sinais , NADPH Oxidases/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Miócitos de Músculo Liso/metabolismo , NADPH Oxidase 1/metabolismo
5.
Chem Asian J ; 19(4): e202301036, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38230541

RESUMO

Malignant tumors seriously threaten human life and well-being. Emerging Near-infrared II (NIR-II, 1000-1700 nm) phototheranostic nanotechnology integrates diagnostic and treatment modalities, offering merits including improved tissue penetration and enhanced spatiotemporal resolution. This remarkable progress has opened promising avenues for advancing tumor theranostic research. The tumor microenvironment (TME) differs from normal tissues, exhibiting distinct attributes such as hypoxia, acidosis, overexpressed hydrogen peroxide, excess glutathione, and other factors. Capitalizing on these attributes, researchers have developed TME-activatable NIR-II phototheranostic agents with diagnostic and therapeutic attributes concurrently. Therefore, developing TME-activatable NIR-II phototheranostic agents with diagnostic and therapeutic activation holds significant research importance. Currently, research on TME-activatable NIR-II phototheranostic agents is still in its preliminary stages. This review examines the recent advances in developing dual-functional NIR-II activatable phototheranostic agents over the past years. It systematically presents NIR-II phototheranostic agents activated by various TME factors such as acidity (pH), hydrogen peroxide (H2 O2 ), glutathione (GSH), hydrogen sulfide (H2 S), enzymes, and their hybrid. This encompasses NIR-II fluorescence and photoacoustic imaging diagnostics, along with therapeutic modalities, including photothermal, photodynamic, chemodynamic, and gas therapies triggered by these TME factors. Lastly, the difficulties and opportunities confronting NIR-II activatable phototheranostic agents in the simultaneous diagnosis and treatment field are highlighted.


Assuntos
Nanopartículas , Neoplasias , Humanos , Fototerapia/métodos , Nanomedicina Teranóstica/métodos , Microambiente Tumoral , Peróxido de Hidrogênio , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Glutationa , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
6.
Biomed Eng Online ; 23(1): 9, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254133

RESUMO

BACKGROUND: Atherosclerosis may be linked to morphological defects that lead to variances in coronary artery hemodynamics. Few objective strategies exit at present for generalizing morphological phenotypes of coronary arteries in terms of hemodynamics. We used unsupervised clustering (UC) to classify the morphology of the left main coronary artery (LM) and looked at how hemodynamic distribution differed between phenotypes. METHODS: In this study, 76 LMs were obtained from 76 patients. After LMs were reconstructed with coronary computed tomography angiography, centerlines were used to extract the geometric characteristics. Unsupervised clustering was carried out using these characteristics to identify distinct morphological phenotypes of LMs. The time-averaged wall shear stress (TAWSS) for each phenotype was investigated by means of computational fluid dynamics (CFD) analysis of the left coronary artery. RESULTS: We identified four clusters (i.e., four phenotypes): Cluster 1 had a shorter stem and thinner branches (n = 26); Cluster 2 had a larger bifurcation angle (n = 10); Cluster 3 had an ostium at an angulation to the coronary sinus and a more curved stem, and thick branches (n = 10); and Cluster 4 had an ostium at an angulation to the coronary sinus and a flatter stem (n = 14). TAWSS features varied widely across phenotypes. Nodes with low TAWSS (L-TAWSS) were typically found around the branching points of the left anterior descending artery (LAD), particularly in Cluster 2. CONCLUSION: Our findings demonstrated that UC is a powerful technique for morphologically classifying LMs. Different LM phenotypes exhibited distinct hemodynamic characteristics in certain regions. This morphological clustering method could aid in identifying people at high risk for developing coronary atherosclerosis, hence facilitating early intervention.


Assuntos
Vasos Coronários , Coração , Humanos , Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Hemodinâmica , Fenótipo
7.
Adv Healthc Mater ; 13(10): e2303451, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37983596

RESUMO

Chemodynamic therapy (CDT) is a particular oncological therapeutic strategy by generates the highly toxic hydroxyl radical (•OH) from the dismutation of endogenous hydrogen peroxide (H2O2) via Fenton or Fenton-like reactions. However, single CDT therapies have been limited by unsatisfactory efficacy. Enhanced chemodynamic therapy (ECDT) triggered by near-infrared (NIR) is a novel therapeutic modality based on light energy to improve the efficiency of Fenton or Fenton-like reactions. However, the limited penetration and imaging capability of the visible (400-650 nm) and traditional NIR-I region (650-900 nm) light-amplified CDT restrict the prospects for its clinical application. Combined with the high penetration/high precision imaging characteristics of the second near-infrared (NIR-II,) nanoplatform, it is expected to kill deep tumors efficiently while imaging the treatment process in real-time, and more notably, the NIR-II region radiation with wavelengths above 1000 nm can minimize the irradiation damage to normal tissues. Such NIR-II ECDT nanoplatforms have greatly improved the effectiveness of CDT therapy and demonstrated extraordinary potential for clinical applications. Accordingly, various strategies have been explored in the past years to improve the efficiency of NIR-II Enhanced CDT. In this review, the mechanisms and strategies used to improve the performance of NIR-II-enhanced CDT are outlined.


Assuntos
Nanopartículas , Neoplasias , Humanos , Peróxido de Hidrogênio , Fototerapia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Microambiente Tumoral
8.
Huan Jing Ke Xue ; 44(12): 6823-6832, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098407

RESUMO

Using diammonium hydrogen phosphate as an activator and N and P source and and bamboo chips as the carbon source, N, P co-doped activated carbon was prepared by one-step pyrolysis and used to efficiently remove La3+ in aqueous solutions. The effects of activation temperature and pH value on the adsorption performance of La3+ were analyzed, and the activation and adsorption mechanisms were explored using TG-IR, SEM-EDX, pore structure, XPS, and hydrophilicity. The results showed that diammonium hydrogen phosphate easily decomposed at a high temperature to produce ammonia and phosphoric acid, which activated the material and promoted the increase in the specific surface area and pore volume of the activated carbon. As an N and P source, the addition of diammonium hydrogen phosphate successfully achieved the N, P co-doping of activated carbon, and the introduction of N- and P-containing functional groups was the key to enhance the adsorption of La3+. Among them, graphitic nitrogen could provide interactions between La3+-π bonds, and C-P=O and C/P-O-P could provide active sites for the adsorption of La3+ through complexation and electrostatic interaction. The adsorption of La3+ on N, P co-doped activated carbons was endothermic and spontaneous, and the adsorption process conformed to the Langmuir isotherm and secondary kinetic model. Under the process conditions of an activation temperature of 900℃ and pH=6, the adsorption capacity of the N, P co-doped activated carbon was as high as 55.18 mg·g-1, which was 2.53 times higher than that of the undoped sample, and its adsorption selectivity for La3+ in the La3+/Na+and La3+/Ca2+ coexistence systems reached 93.49% and 82.49%, respectively. Additionally, the removal efficiency remained above 54% after five successive adsorption-desorption cycle experiments.

9.
Adv Sci (Weinh) ; 10(36): e2304104, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37983599

RESUMO

Tumor microenvironment (TME)-triggered phototheranostic platform offers a feasible strategy to improve cancer diagnosis accuracy and minimize treatment side effects. Developing a stable and biocompatible molecular phototheranostic platform for TME-activated second near-infrared (NIR-II) fluorescence imaging-guided multimodal cascade therapy is a promising strategy for creating desirable anticancer agents. Herein, a new NIR-II fluorescence imaging-guided activatable molecular phototheranostic platform (IR-FEP-RGD-S-S-S-Fc) is presented for actively targeted tumor imaging and hydrogen sulfide (H2 S) gas-enhanced chemodynamic-hypothermal photothermal combined therapy (CDT/HPTT). It is revealed for the first time that the coupling distance between IR-FE and ferrocene is proportional to the photoinduced electron transfer (PET), and the aqueous environment is favorable for PET generation. The part of Cyclic-RGDfK (cRGDfk) peptides can target the tumor and benefit the endocytosis of nanoparticles. The high-concentration glutathione (GSH) in the TME will separate the fluorescence molecule and ferrocene by the GSH-sensitive trisulfide bond, realizing light-up NIR-II fluorescence imaging and a cascade of trimodal synergistic CDT/HPTT/gas therapy (GT). In addition, the accumulation of hydroxyl radicals (•OH) and down-regulation of glutathione peroxidase 4 (GPX4) can produce excessive harmful lipid hydroperoxides, ultimately leading to ferroptosis.


Assuntos
Neoplasias , Terapia Fototérmica , Humanos , Metalocenos , Imagem Óptica , Glutationa , Microambiente Tumoral
10.
Front Nutr ; 10: 1266584, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37964929

RESUMO

Background: The primary objective of this study was to investigate the effects of oral omega-3 fatty acids in lowering the risk of malnutrition and improving the inflammatory response in patients with stage II-III lung cancer receiving postoperative chemotherapy. Methods: One hundred and three lung cancer patients identified as being at risk for malnutrition according to the 2002 nutritional risk screening criteria were randomized into either the omega-3 fatty acid supplementation group or the placebo group during postoperative chemotherapy. Data on anthropometric parameters, laboratory nutritional indicators, and inflammatory markers were collected, and changes and differences between the two groups were compared and analyzed. Results: Sixty three patients were included in the final analysis. The baseline information of the two groups of patients was comparable (p > 0.05). After 12 weeks, patients in the treatment group exhibited significantly higher levels of hemoglobin (11.26 ± 1.25 vs.10.60 ± 0.94, p = 0.021) and serum albumin (45.38 ± 5.06 vs.42.66 ± 5.06, p = 0.036) compared with those in the placebo group. Meanwhile, the levels of inflammatory factors C-reactive protein (2.16 ± 1.06 vs. 4.11 ± 1.72, p < 0.001), interleukin-1 (6.61 ± 2.19 vs.10.85 ± 3.61, p < 0.001), interleukin-6 (2.48 ± 1.20 vs. 4.53 ± 0.98, p < 0.001), interleukin-8 (9.26 ± 2.69 vs. 39.01 ± 6.53, p < 0.001), and tumor necrosis factor-α (1.88 ± 0.60 vs. 4.07 ± 0.97, p < 0.001) were significantly decreased in the treatment group. In contrast, differences in weight, BMI, upper arm circumference, triceps skinfold thickness, triglycerides, cholesterol, and IFN-γ between the two groups were not statistically significant (p > 0.05). Finally, in the treatment group, the levels of hemoglobin (10.89 ± 1.15 vs. 11.82 ± 1.21, p = 0.042), triglyceride (0.92 ± 0.29 vs. 1.03 ± 0.22, p = 0.043), and cholesterol (3.56 ± 0.82 vs. 4.23 ± 0.88, p = 0.045) were higher in stage II patients after the intervention compared with stage III patients. Conclusion: Supplementation with omega-3 fatty acids improved nutritional status and reduced chronic inflammatory responses in patients with stage II-III non-small cell lung cancer undergoing postoperative chemotherapy. Clinical Trial Registration: AEA RCT Registry, identifier AEARCTR-0007165.

11.
Anal Chem ; 95(47): 17372-17383, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37963241

RESUMO

The activable NIR-based phototheranostic nanoplatform (NP) is considered an efficient and reliable tumor treatment due to its strong targeting ability, flexible controllability, minimal side effects, and ideal therapeutic effect. This work describes the rational design of a second near-infrared (NIR-II) fluorescence imaging-guided organic phototheranostic NP (FTEP-TBFc NP). The molecular-engineered phototheranostic NP has a sensitive response to glutathione (GSH), generating hydrogen sulfide (H2S) gas, and delivering ferrocene molecules in the tumor microenvironment (TME). Under 808 nm irradiation, FTEP-TBFc could not only simultaneously generate fluorescence, heat, and singlet oxygen but also greatly enhance the generation of reactive oxygen species to improve chemodynamic therapy (CDT) and photodynamic therapy (PDT) at a biosafe laser power of 0.33 W/cm2. H2S inhibits the activity of catalase and cytochrome c oxidase (COX IV) to cause the enhancement of CDT and hypothermal photothermal therapy (HPTT). Moreover, the decreased intracellular GSH concentration further increases CDT's efficacy and downregulates glutathione peroxidase 4 (GPX4) for the accumulation of lipid hydroperoxides, thus causing the ferroptosis process. Collectively, FTEP-TBFc NPs show great potential as a versatile and efficient NP for specific tumor imaging-guided multimodal cancer therapy. This unique strategy provides new perspectives and methods for designing and applying activable biomedical phototheranostics.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Microambiente Tumoral , Fotoquimioterapia/métodos , Terapia Combinada , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Imagem Óptica , Linhagem Celular Tumoral , Nanomedicina Teranóstica/métodos
12.
Eur J Med Chem ; 261: 115751, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37688938

RESUMO

The difference in the secondary binding site (SBS) between the dopamine 2 receptor (D2R) and dopamine 3 receptor (D3R) has been used in the design of compounds displaying selectivity for the D3R versus D2R. In the current study, a series of bitopic ligands based on Fallypride were prepared with various secondary binding fragments (SBFs) as a means of improving the selectivity of this benzamide analog for D3R versus D2R. We observed that compounds having a small alkyl group with a heteroatom led to an improvement in D3R versus D2R selectivity. Increasing the steric bulk in the SBF increase the distance between the pyrrolidine N and Asp110, thereby reducing D3R affinity. The best-in-series compound was (2S,4R)-trans-27 which had a modest selectivity for D3R versus D2R and a high potency in the ß-arrestin competition assay which provides a measure of the ability of the compound to compete with endogenous dopamine for binding to the D3R. The results of this study identified factors one should consider when designing bitopic ligands based on Fallypride displaying an improved affinity for D3R versus D2R.


Assuntos
Dopamina , Receptores de Dopamina D3 , Receptores de Dopamina D3/química , Benzamidas/farmacologia , Ligantes
13.
Huan Jing Ke Xue ; 44(8): 4611-4622, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694654

RESUMO

Despite the essential role of soil microorganisms in nutrient turnover in soil ecological systems and the recognized paramount significance of microbial necromass to soil organic carbon accumulation, how microbial community abundance and necromass respond to land use intensification level regulation remains poorly understood. To address this knowledge gap, based on the land use intensification level, three treatments were set up[annual wheat-maize rotation (CC), alternating temporary grassland with wheat planting (TG), and perennial grassland (PG)], and a long-term fixed filed experiment was established to investigate the influences of the regulation of land use intensification level on bacterial and fungal community abundances; the accumulation of bacterial, fungal, and total microbial necromass; and their contributions to SOC sequestration using droplet digital PCR and amino sugar detection technologies. We further sought to determine the key factors driving the bacterial, fungal, and total microbial necromass C accumulation. Our results demonstrated that fungal community abundance was strongly affected by land use intensification level regulation compared to that of the bacterial community, which increased with decreasing land use intensification level. The total microbial necromass C predominated the SOC accumulation across all three land use intensification levels, which contributed 52.78%, 58.36%, and 68.87% to SOC, respectively, exhibiting an increasing trend with the decline in land use intensification level. Fungal necromass C accounted for more than 80% of the total microbial necromass C, indicating its predominance in the accumulation of the total microbial necromass C and active variation via the reduction in land use intensification level. There was no significant difference in bacterial necromass C (MurA) content, with the trend of CC

Assuntos
Microbiota , Solo , Carbono , China , Produtos Agrícolas
14.
bioRxiv ; 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37577467

RESUMO

Ciliary motility requires the spatiotemporal coordination of multiple dynein motors by regulatory complexes located within the 96 nm axoneme repeat. Many organisms can alter ciliary waveforms in response to internal or external stimuli, but little is known about the specific polypeptides and structural organization of complexes that regulate waveforms. In Chlamydomonas, several mutations convert the ciliary waveform from an asymmetric, ciliary-type stroke to a symmetric, flagellar-type stroke. Some of these mutations alter subunits located at the inner junction of the doublet microtubule and others alter interactions between the dynein arms and the radial spokes. These and other axonemal substructures are interconnected by a network of poorly characterized proteins. Here we re-analyze several motility mutants (mbo, fap57, pf12/pacrg) to identify new components in this network. The mbo (move backwards only) mutants are unable to swim forwards with an asymmetric waveform. Proteomics identified more than 19 polypeptides that are missing or reduced in mbo mutants, including one inner dynein arm, IDA b. Several MBO2-associated proteins are also altered in fap57 and pf12/parcg mutants, suggesting overlapping networks. Two subunits are highly conserved, coiled coil proteins found in other species with motile cilia and others contain potential signaling domains. Cryo-electron tomography and epitope tagging revealed that the MBO2 complex is found on specific doublet microtubules and forms a large, L-shaped structure that contacts the base of IDA b that interconnects multiple dynein regulatory complexes and varies in a doublet microtubule specific fashion.

15.
Toxicol Appl Pharmacol ; 470: 116547, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178933

RESUMO

Daunorubicin (DNR-) induced cardiotoxicity seriously restricts its clinical application. Transient receptor potential cation channel subfamily C member 6 (TRPC6) is involved in multiple cardiovascular physiological and pathophysiological processes. However, the role of TRPC6 anthracycline-induced cardiotoxicity (AIC) remains unclear. Mitochondrial fragmentation greatly promotes AIC. TRPC6-mediated ERK1/2 activation has been shown to favor mitochondrial fission in dentate granule cells. The aim of the present study was to elucidate the effects of TRPC6 on daunorubicin- induced cardiotoxicity and identify the mechanisms associated with mitochondrial dynamics. The sparkling results showed that TRPC6 was upregulated in models in vitro and in vivo. TRPC6 knockdown protected cardiomyocytes from DNR-induced cell apoptosis and death. DNR largely facilitated mitochondrial fission, boosted mitochondrial membrane potential collapse and damaged debilitated mitochondrial respiratory function in H9c2 cells,these effects were accompanied by TRPC6 upregulation. siTRPC6 effectively inhibited these mitochondrial adverse aspects showing a positive unexposed effect on mitochondrial morphology and function. Concomitantly, ERK1/2-DRP1 which is related to mitochondrial fission was significantly activated with amplified phosphorylated forms in DNR-treated H9c2 cells. siTRPC6 effectively suppressed ERK1/2-DPR1 over activation, hinting at a potential correlation between TRPC6 and ERK1/2-DRP1 by which mitochondrial dynamics are possibly modulated in AIC. TRPC6 knockdown also raised the Bcl-2/Bax ratio, which may help to block mitochondrial fragmentation-related functional impairment and apoptotic signaling. These findings suggested an essential role of TRPC6 in AIC by intensifying mitochondrial fission and cell death via ERK1/2-DPR1, which could be a potential therapeutic target for AIC.


Assuntos
Daunorrubicina , Miócitos Cardíacos , Canal de Cátion TRPC6 , Animais , Ratos , Apoptose , Cardiotoxicidade/metabolismo , Morte Celular , Daunorrubicina/toxicidade , Dinaminas/metabolismo , Sistema de Sinalização das MAP Quinases , Dinâmica Mitocondrial , Miócitos Cardíacos/metabolismo , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo , Canal de Cátion TRPC6/metabolismo
16.
Small ; 19(26): e2207995, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942859

RESUMO

Effectively interfering energy metabolism in tumor cells and simultaneously activating the in vivo immune system to perform immune attacks are meaningful for tumor treatment. However, precisely targeted therapy is still a huge challenge. Herein, a mitochondrial-targeting phototheranostic system, FE-T nanoparticles (FE-T NPs) are developed to damage mitochondria in tumor cells and change the tumor immunosuppressive microenvironment. FE-T NPs are engineered by encapsulating the near-infrared (NIR) absorbed photosensitizer IR-FE-TPP within amphiphilic copolymer DSPE-SS-PEG-COOH for high-performing with simultaneous mitochondrial-targeting, near-infrared II (NIR-II) fluorescence imaging, and synchronous photothermal therapy (PTT) /photodynamic therapy (PDT) /immune therapy (IMT). In tumor treatment, the disulfide in the copolymer can be cleaved by excess intracellular glutathione (GSH) to release IR-FE-TPP and accumulate in mitochondria. After 808 nm irradiation, the mitochondrial localization of FE-T NPs generated reactive oxygen species (ROS), and hyperthermia, leading to mitochondrial dysfunction, photoinductive apoptosis, and immunogenic cell death (ICD). Notably, in situ enhanced PDT/PTT in vivo via mitochondrial-targeting with FE-T NPs boosts highly efficient ICD toward excellent antitumor immune response. FE-T NPs provide an effective mitochondrial-targeting phototheranostic nanoplatform for imaging-guided tumor therapy.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Terapia Combinada , Fármacos Fotossensibilizantes , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Polímeros , Mitocôndrias , Fotoquimioterapia/métodos , Linhagem Celular Tumoral , Fototerapia/métodos , Microambiente Tumoral
17.
Nat Commun ; 14(1): 1775, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36997532

RESUMO

The apical complex is a specialized collection of cytoskeletal and secretory machinery in apicomplexan parasites, which include the pathogens that cause malaria and toxoplasmosis. Its structure and mechanism of motion are poorly understood. We used cryo-FIB-milling and cryo-electron tomography to visualize the 3D-structure of the apical complex in its protruded and retracted states. Averages of conoid-fibers revealed their polarity and unusual nine-protofilament arrangement with associated proteins connecting and likely stabilizing the fibers. Neither the structure of the conoid-fibers nor the architecture of the spiral-shaped conoid complex change during protrusion or retraction. Thus, the conoid moves as a rigid body, and is not spring-like and compressible, as previously suggested. Instead, the apical-polar-rings (APR), previously considered rigid, dilate during conoid protrusion. We identified actin-like filaments connecting the conoid and APR during protrusion, suggesting a role during conoid movements. Furthermore, our data capture the parasites in the act of secretion during conoid protrusion.


Assuntos
Neospora , Toxoplasma , Toxoplasma/citologia , Toxoplasma/ultraestrutura , Neospora/citologia , Neospora/ultraestrutura , Tomografia com Microscopia Eletrônica , Tubulina (Proteína)/ultraestrutura , Citoesqueleto/ultraestrutura , Membrana Celular/ultraestrutura
18.
Mikrochim Acta ; 190(2): 58, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653726

RESUMO

Metallic aerogels (MAs) are self-supported porous nanomaterials with excellent catalytic activity, which could be a promising candidate for high-performance nanozymes. The interface regulation by heteroatom and vacancies is an effective strategy for boosting the enzyme-mimicking activity. Herein, magnetic RuCo aerogels with doping of boron and oxygen vacancies were prepared by a one-pot spontaneous NaBH4 gelation method under a low temperature. The three-dimensional network structure with high specific surface area and interlinked pores of RuCo aerogels afford abundant active sites to facilitate the interaction with substrates. Moreover, the monolithic structure avoided conventional aggregation, thus enhancing stability during catalysis. Introducing elemtal boron and oxygen vacancies adjusted the electronic structure of RuCo aerogels to achieve enhanced enzyme-like performances. It is found that the RuCo aerogel nanozyme can mimic nature peroxidase, demonstrating their viable applications in the bioassay of H2O2 and glucose. The constructed glucose sensor possesses acceptable sensitivity and stability with a linear range of 0.002 ~ 5 mM and a low detection limit (1.66 µM). This work provides insights into the rational design of advanced nanozymes and paves the avenue for the applications of metallic aerogels in the bioassay field. A boron-doped RuCo bimetallic aerogel with rich oxygen vacancies was prepared by a facile self-assembly method under an ice bath. The unique physical and electronic structure of RuCo aerogel results in the improvement of the intrinsic peroxidaselike activity, and thus, a sensitive and robust colorimetric glucose sensor could be developed.


Assuntos
Boro , Colorimetria , Colorimetria/métodos , Peróxido de Hidrogênio/química , Oxigênio , Glucose/química , Peroxidases/química , Fenômenos Magnéticos
19.
Neural Regen Res ; 18(2): 404-409, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35900437

RESUMO

Our previous study demonstrated the potential therapeutic role of human neural stem cell-derived exosomes (hNSC-Exo) in ischemic stroke. Here, we loaded brain-derived neurotrophic factor (BDNF) into exosomes derived from NSCs to construct engineered exosomes (BDNF-hNSC-Exo) and compared their effects with those of hNSC-Exo on ischemic stroke both in vitro and in vivo. In a model of H2O2-induced oxidative stress in NSCs, BDNF-hNSC-Exo markedly enhanced cell survival. In a rat middle cerebral artery occlusion model, BDNF-hNSC-Exo not only inhibited the activation of microglia, but also promoted the differentiation of endogenous NSCs into neurons. These results suggest that BDNF can improve the function of NSC-derived exosomes in the treatment of ischemic stroke. Our research may support the clinical use of other neurotrophic factors for central nervous system diseases.

20.
Molecules ; 29(1)2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38202706

RESUMO

A series of bitopic ligands based on Fallypride with a flexible secondary binding fragment (SBF) were prepared with the goal of preparing a D3R-selective compound. The effect of the flexible linker ((R,S)-trans-2a-d), SBFs ((R,S)-trans-2h-j), and the chirality of orthosteric binding fragments (OBFs) ((S,R)-trans-d, (S,R)-trans-i, (S,S)-trans-d, (S,S)-trans-i, (R,R)-trans-d, and (R,R)-trans-i) were evaluated in in vitro binding assays. Computational chemistry studies revealed that the interaction of the fragment binding to the SBF increased the distance between the pyrrolidine nitrogen and ASP1103.32 of the D3R, thereby reducing the D3R affinity to a suboptimal level.


Assuntos
Química Computacional , Nitrogênio , Ligantes , Projetos de Pesquisa
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