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1.
Brief Bioinform ; 24(1)2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36528804

RESUMO

The rapid progress of machine learning (ML) in predicting molecular properties enables high-precision predictions being routinely achieved. However, many ML models, such as conventional molecular graph, cannot differentiate stereoisomers of certain types, particularly conformational and chiral ones that share the same bonding connectivity but differ in spatial arrangement. Here, we designed a hybrid molecular graph network, Chemical Feature Fusion Network (CFFN), to address the issue by integrating planar and stereo information of molecules in an interweaved fashion. The three-dimensional (3D, i.e., stereo) modality guarantees precision and completeness by providing unabridged information, while the two-dimensional (2D, i.e., planar) modality brings in chemical intuitions as prior knowledge for guidance. The zipper-like arrangement of 2D and 3D information processing promotes cooperativity between them, and their synergy is the key to our model's success. Experiments on various molecules or conformational datasets including a special newly created chiral molecule dataset comprised of various configurations and conformations demonstrate the superior performance of CFFN. The advantage of CFFN is even more significant in datasets made of small samples. Ablation experiments confirm that fusing 2D and 3D molecular graphs as unambiguous molecular descriptors can not only effectively distinguish molecules and their conformations, but also achieve more accurate and robust prediction of quantum chemical properties.


Assuntos
Aprendizado de Máquina , Estereoisomerismo , Conformação Molecular
2.
J Am Chem Soc ; 146(1): 811-823, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157302

RESUMO

Accurately and rapidly acquiring the microscopic properties of a material is crucial for catalysis and electrochemistry. Characterization tools, such as spectroscopy, can be a valuable tool to infer these properties, and when combined with machine learning tools, they can theoretically achieve fast and accurate prediction results. However, on the path to practical applications, training a reliable machine learning model is faced with the challenge of uneven data distribution in a vast array of non-negligible solvent types. Herein, we employ a combination of the first-principles-based approach and data-driven model. Specifically, we utilize density functional theory (DFT) to calculate theoretical spectral data of CO-Ag adsorption in 23 different solvent systems as a data source. Subsequently, we propose a hierarchical knowledge extraction multiexpert neural network (HMNN) to bridge the knowledge gaps among different solvent systems. HMNN undergoes two training tiers: in tier I, it learns fundamental quantitative spectra-property relationships (QSPRs), and in tier II, it inherits the fundamental QSPR knowledge from previous steps through a dynamic integration of expert modules and subsequently captures the solvent differences. The results demonstrate HMNN's superiority in estimating a range of molecular adsorbate properties, with an error range of less than 0.008 eV for zero-shot predictions on unseen solvents. The findings underscore the usability, reliability, and convenience of HMNN and could pave the way for real-time access to microscopic properties by exploiting QSPR.

3.
Inflammopharmacology ; 32(1): 893-901, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100033

RESUMO

Emerging evidence suggests that the gastrointestinal tract plays a crucial role in the pathophysiology of sepsis, a leading cause of mortality among patients admitted to the intensive care unit (ICU). Malvidin, belonging to the flavonoid family of compounds, exhibits a range of capabilities including anti-inflammatory and antioxidant properties. Studies have demonstrated that Malvidin exhibits a dose-dependent effect in mitigating sepsis-induced intestinal injury. The advantageous impact of Malvidin in safeguarding against sepsis-induced intestinal injury is associated with its capacity to counteract oxidative stress, inhibit cellular apoptosis, diminish the secretion of pro-inflammatory cytokines, and regulate the synthesis of inflammasomes. The findings indicate that Malvidin, a natural compound, exhibits protective effects on the gut by activating the nuclear factor erythroid 2-related factor 2/reactive oxygen species/NLRP3 inflammasome pathway. These results have significant implications for potential clinical applications and offer valuable insights into the treatment of sepsis-induced intestinal injury.


Assuntos
Antocianinas , Inflamassomos , Sepse , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio , Lipopolissacarídeos , Sepse/tratamento farmacológico
4.
Phys Chem Chem Phys ; 25(11): 7893-7900, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36857719

RESUMO

Molecular recognition towards peptides and proteins with high affinity by synthetic supramolecular hosts is important but challenging. In this work, we investigate the molecular recognition of the synthetic cucurbit[7]uril (CB[7]) to 17 designed N-terminal Leu-containing tripeptides in aqueous medium by molecular dynamics (MD) simulation and screen out tripeptides with high binding affinity. It is found that, compared to LGG, only the third residue is Arg (R), the binding affinity of CB[7] to LGR reaches nanomolar level with binding equilibrium constant (Ka) of 1.1 × 109 M-1. The CB[7] recognition to the N-terminal Leu-containing tripeptides is highly sequence dependent; whether changing the sequence order (from LGR to LRG) or increasing the sequence length (from LGR to LGGR), Ka decreases by about three orders of magnitude. Interestingly, substituting N-terminal Leu for its isomer Ile, the binding of CB[7] to tripeptides weakens significantly with Ka decreasing by 3-8 orders of magnitude. Thus CB[7] can effectively distinguish N-terminal Leu-containing tripeptides from N-terminal Ile-containing tripeptides. Importantly, we predict that when R is as C-terminus, regardless of N-terminal residue being of aromatic type or Leu, the binding strength is always close to the nanomolar level. Therefore, R can be introduced to rationally design novel peptides with high binding affinity to CB[7] in practical applications.


Assuntos
Imidazóis , Compostos Macrocíclicos , Imidazóis/química , Compostos Macrocíclicos/química , Peptídeos/química , Proteínas , Hidrocarbonetos Aromáticos com Pontes/química
5.
Acta Pharmacol Sin ; 44(3): 680-692, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36114272

RESUMO

The growth of solid tumors depends on tumor vascularization and the endothelial cells (ECs) that line the lumen of blood vessels. ECs generate a large fraction of ATP through glycolysis, and elevation of their glycolytic activity is associated with angiogenic behavior in solid tumors. 6-Phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) positively regulates glycolysis via fructose-2/6-bisphosphate, the product of its kinase activity. Partial inhibition of glycolysis in tumor ECs by targeting PFKFB3 normalizes the otherwise abnormal tumor vessels, thereby reducing metastasis and improving the outcome of chemotherapy. Although a limited number of tool compounds exist, orally available PFKFB3 inhibitors are unavailable. In this study we conducted a high-throughput screening campaign against the kinase activity of PFKFB3, involving 250,240 chemical compounds. A total of 507 initial hits showing >50% inhibition at 20 µM were identified, 66 of them plus 1 analog from a similarity search consistently displayed low IC50 values (<10 µM). In vitro experiments yielded 22 nontoxic hits that suppressed the tube formation of primary human umbilical vein ECs at 10 µM. Of them, 15 exhibited binding affinity to PFKFB3 in surface plasmon resonance assays, including 3 (WNN0403-E003, WNN1352-H007 and WNN1542-F004) that passed the pan-assay interference compounds screening without warning flags. This study provides potential leads to the development of new PFKFB3 inhibitors.


Assuntos
Ensaios de Triagem em Larga Escala , Neoplasias , Fosfofrutoquinase-2 , Humanos , Glicólise , Células Endoteliais da Veia Umbilical Humana/metabolismo , Neoplasias/metabolismo , Neovascularização Patológica , Fosfofrutoquinase-2/antagonistas & inibidores , Fosfofrutoquinase-2/metabolismo
6.
Angew Chem Int Ed Engl ; 62(21): e202300771, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36949012

RESUMO

While recent work demonstrates the advantages of weakly solvating solvents in enhancing the cyclability of LMBs, both new designs and design strategies for high performance weakly solvating solvent, especially physicochemical properties, are still lacking. Here, we propose a molecular design to tune the solvating power and physicochemical properties of non-fluorinated ether solvent. The resulting cyclopentylmethyl ether (CPME) have a weak solvating power and wide liquid-phase temperature range. By optimizing the salt concentration, the CE is further promoted to 99.4 %. Besides, the improved electrochemical performance of Li-S battery in CPME-based electrolytes is obtained at -20 °C. The Li||LFP (17.6 mg cm-2 ) battery with developed electrolyte maintains >90 % of the original capacity over 400 cycles. Our design concept for solvent molecule provides a promising pathway to non-fluorinated electrolytes with weakly solvating power and wide temperature window for high-energy-density LMBs.

7.
Small ; 18(47): e2203431, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36180405

RESUMO

Mesenchymal stem cell (MSC) therapy via intravenous transplantation exhibits great potential for brain tissue regeneration, but still faces thorny clinical translation challenges as the unknown dynamic fate leads to the contentious therapeutic mechanism and the poor MSC viability in harsh lesions limits therapeutic efficiency. Here, a vitality-enhanced dual-modal tracking system is designed to improve engraftment efficiency and is utilized to noninvasively explore the fate of intravenous transplanted human umbilical cord-derived MSCs during long-term treatment of ischemic stroke. Such a system is obtained by bioorthogonally conjugating magnetic resonance imaging (MRI) contrast and near-infrared fluorescence (NIRF) imaging nanoparticles to metabolic glycoengineered MSCs with a lipoic acid-containing extracellular antioxidative protective layer. The dynamic fates of MSCs in multi-dimensional space-time evolution are digitally detailed for up to 28 days using MRI and NIRF imaging equipment, and the protective layer greatly shields MSCs from reactive oxygen spices (ROS) degradation, enhances MSC survival, and engraftment efficiency. Additionally, it is observed that the bioengineered MSCs exhibit dynamic intelligent responses corresponding to microenvironment remodeling and exert enhanced therapeutic effects. This dual-modal tracking system enables long-term tracking of MSCs while improving their viability at the lesion sites, which may serve as a valuable tool for expediting the clinical translation of MSC therapy.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/metabolismo , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia
8.
Bioorg Med Chem ; 64: 116776, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35483137

RESUMO

Cardiovascular diseases are increasingly threating the global human health, hypertension is the most important risk factor for cardiovascular and cerebrovascular diseases. To improve the antihypertensive activity and cardiovascular protective effect of natural product (±)-7,8-dihydroxy-3-methyl-isochroman-4-one [(±)-XJP], a series of novel H2S-releasing isochroman-4-one derivatives were designed and synthesized by coupling hydrogen sulfide (H2S)-releasing donors with the analogs of (±)-XJP. Further, the H2S-releasing assay indicated that some target compounds showed excellent H2S generating ability. Moreover, these novel hybrids exhibited moderate to good in vitro vasodilation efficacy. Among them, the most potent compound exhibited potent in vivo antihypertensive activity with the maximum antihypertensive amplitude about 27%, which was more potent than that of the lead compound (±)-XJP. These results suggested that the hybridization of H2S-donors and (±)-XJP analogs may provide a promising approach for the discovery of novel antihypertensive agents.


Assuntos
Sulfeto de Hidrogênio , Hipertensão , Anti-Hipertensivos , Humanos , Sulfeto de Hidrogênio/farmacologia , Hipertensão/tratamento farmacológico , Vasodilatação
9.
J Nanobiotechnology ; 20(1): 394, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045429

RESUMO

Epithelial-mesenchymal transition (EMT), a differentiation process with aberrant changes of tumor cells, is identified as an initial and vital procedure for metastatic processes. Inflammation is a significant inducer of EMT and provides an indispensable target for blocking EMT, however, an anti-inflammatory therapeutic with highlighted safety and efficacy is deficient. Metformin is a promising anti-inflammatory agent with low side effects, but tumor monotherapy with an anti-inflammation drug could generate therapy resistance, cell adaptation or even promote tumor development. Combination therapies with various anti-inflammatory mechanisms can be favorable options improving therapeutic effects of metformin, here we develop a tumor targeting hybrid micelle based on metformin and a histone deacetylase inhibitor propofol-docosahexaenoic acid for efficient therapeutic efficacies of anti-inflammatory drugs. Triptolide is further encapsulated in hybrid micelles for orthotopic tumor therapies. The final multifunctional nanoplatforms (HAOPTs) with hyaluronic acid (HA) modification can target tumor efficiently, inhibit tumor cell EMT processes, repress metastasis establishment and suppress metastatic tumor development in a synergistic manner. Collectively, the results afford proof of concept that the tumor targeting anti-inflammatory nanoplatform can provide a potent, safe and clinical translational approach for EMT inhibition and metastatic tumor therapy.


Assuntos
Metformina , Neoplasias , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Metformina/farmacologia , Metformina/uso terapêutico
10.
Ecotoxicol Environ Saf ; 243: 113961, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35969982

RESUMO

Avermectin, a "low toxicity insecticide", has been widely used in recent years, but its non-target toxicity, especially to aquatic organisms, has been neglected. In this study, we evaluated the neurotoxic effects of avermectin on carp by establishing a 96 h avermectin acute toxicity test, and its possible mechanism was discussed. The 96 h LC50 of avermectin in carp was found to be 24.04 µg/L. Therefore, 3.005 µg/L and 12.02 µg/L were used as the low-dose and high-dose groups, respectively, to investigate the neurotoxic effects of avermectin on carp. The results of high-performance liquid chromatography (HPLC) analysis showed that avermectin accumulated in the carp brain. Histopathological observation and immunohistochemical analysis (IHC) of TNF-α and Bax showed that avermectin exposure led to inflammatory cell infiltration and neuronal necrosis. The mRNA levels of tight junction genes and the IHC results of ZO-1 and Occludin showed that the structure of the blood-brain barrier (BBB) was destroyed. Biochemical analysis showed that avermectin induced the accumulation of MDA in the brain and decreased the activity of antioxidant enzymes CAT and SOD, leading to oxidative stress. In addition, avermectin induces brain inflammation by activating NF-κB pathway and releasing inflammatory factors IL-1ß, IL-6, TNF-α and iNOS. TEM and TUNEL assays showed that exposure to avermectin induced apoptosis in brain. what is more, the expression of apoptosis-related genes and proteins suggested that avermectin-induced apoptosis may be associated with inhibition of the PI3K/Akt signaling pathway. This study also showed that avermectin-induced NF-κB signaling activation was partially dependent on its upstream PI3K/Akt signaling pathway. Therefore, this study concludes that avermectin can induce neurotoxicity in carp by disrupting the blood-brain barrier structure and generating oxidative stress, inflammation, and apoptosis and that NF-κB and PI3K/Akt signaling pathways are involved in this process.


Assuntos
Carpas , NF-kappa B , Animais , Apoptose , Barreira Hematoencefálica/metabolismo , Carpas/metabolismo , Inflamação/induzido quimicamente , Inflamação/patologia , Ivermectina/análogos & derivados , NF-kappa B/genética , NF-kappa B/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Pestic Biochem Physiol ; 187: 105190, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36127050

RESUMO

Avermectin is one of the most widely used pesticides, but its toxicity to non-target organisms, especially aquatic organisms, has been ignored. Therefore, an acute spleen injury model of avermectin in carp was established to assess the non-target toxicity of avermectin to carp. In this study, 3.005 µg/L and 12.02 µg/L were set as the low and high dose groups of avermectin, respectively, and a four days acute exposure experiment was conducted. Pathological structure observation showed that avermectin damaged spleen tissue structure and produced inflammatory cell infiltration. Biochemical analysis showed that avermectin significantly reduced the activities of antioxidant enzymes CAT, SOD, and GSH-px, but increased the content of MDA, a marker of oxidative damage. Avermectin exposure also significantly increased the transcription levels of inflammatory cytokines such as IL-1ß, IL-6, TNF-α, and INOS, and also significantly enhanced the activity of the inflammatory mediator iNOS, but suppressed the transcription levels of anti-inflammatory factors TGF-ß1 and IL-10. In addition, TUNEL detected that the apoptosis rate increased significantly with the increase of avermectin dosage, and the transcription levels of apoptosis-related genes BAX, P53, and Caspase 3/9 also increased in a dose-dependent manner. This study is preliminary evidence that avermectin induces spleen injury in carp through oxidative stress, inflammation, and apoptosis, which has important implications for subsequent studies on the effects of avermectin on non-target organisms.


Assuntos
Carpas , Praguicidas , Animais , Antioxidantes/metabolismo , Apoptose , Carpas/metabolismo , Caspase 3/metabolismo , Inflamação/induzido quimicamente , Mediadores da Inflamação/farmacologia , Interleucina-10/metabolismo , Interleucina-10/farmacologia , Interleucina-6/farmacologia , Ivermectina/análogos & derivados , Estresse Oxidativo , Praguicidas/farmacologia , Baço/metabolismo , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Necrose Tumoral alfa , Proteína Supressora de Tumor p53 , Proteína X Associada a bcl-2
12.
Molecules ; 27(13)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35807360

RESUMO

Cardiac pathological hypertrophy is associated with undesirable epigenetic changes and causes maladaptive cardiac remodeling and heart failure, leading to high mortality rates. Specific drugs for the treatment of cardiac hypertrophy are still in urgent need. In the present study, a hydrogen-sulfide-releasing hybrid 13-E was designed and synthesized by appending p-hydroxythiobenzamide (TBZ), an H2S-releasing donor, to an analog of our previously discovered cardioprotective natural product XJP, 7,8-dihydroxy-3-methyl-isochromanone-4. This hybrid 13-E exhibited excellent H2S-generating ability and low cellular toxicity. The 13-E protected against cardiomyocyte hypertrophy In Vitro and reduced the induction of Anp and Bnp. More importantly, 13-E could reduce TAC-induced cardiac hypertrophy In Vivo, alleviate cardiac interstitial fibrosis and restore cardiac function. Unbiased transcriptomic analysis showed that 13-E regulated the AMPK signaling pathway and influenced fatty acid metabolic processes, which may be attributed to its cardioprotective activities.


Assuntos
Sulfeto de Hidrogênio , Cardiomegalia/metabolismo , Coração , Humanos , Hidrogênio/farmacologia , Hidrogênio/uso terapêutico , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Miócitos Cardíacos/metabolismo , Sulfetos/farmacologia , Sulfetos/uso terapêutico
13.
Pharm Biol ; 60(1): 1169-1176, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35701112

RESUMO

CONTEXT: S-Propargyl-cysteine (SPRC), an endogenous H2S modulator, exerts anti-inflammatory effects on cardiovascular and neurodegenerative disease, but it remains unknown whether SPRC can prevent autoimmune hepatitis. OBJECTIVE: To evaluate the preventive effect of SPRC on concanavalin A (Con A)-induced liver injury and uncover the underlying mechanisms. MATERIALS AND METHODS: Mice were randomly divided into five groups: control, Con A, SPRC (5 and 10 mg/kg injected intravenously once a day for 7 days), and propargylglycine (PAG; 50 mg/kg injected intraperitoneally 0.5 h before SPRC for 7 days). All mice except the controls were intravenously injected with Con A (20 mg/kg) on day 7. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using kits. Inflammatory cytokines (TNF-α and IFN-γ) in the blood and in the liver were detected by ELISA Kit and real-time PCR, respectively. The expression of mitogen-activated protein kinase (MAPK) pathway proteins (p-JNK and p-Akt) and apoptosis proteins (Bax and Bcl-2) was detected using western blotting. RESULTS: SPRC reduced the levels of AST (p < 0.05) and ALT (p < 0.01) and decreased the release of the inflammatory cytokines. Mechanistically, SPRC increased H2S level (p < 0.05) and promoted cystathionine γ-lyase (CSE) expression (p < 0.05). SPRC inhibited the MAPK pathway activation and the apoptosis pathway. All the effects of SPRC were blocked by the CSE inhibitor PAG. CONCLUSIONS: SPRC prevents Con A-induced liver injury in mice by promoting CSE expression and producing endogenous H2S. The mechanisms include reducing the release of inflammatory cytokines, attenuating MAPK pathway activation, and alleviating apoptosis.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Sulfeto de Hidrogênio , Doenças Neurodegenerativas , Animais , Concanavalina A/toxicidade , Cisteína/farmacologia , Citocinas , Sulfeto de Hidrogênio/metabolismo , Camundongos
14.
Phys Chem Chem Phys ; 23(24): 13724-13733, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34128514

RESUMO

Sequence-selective recognition of cationic amphipathic peptides by synthetic receptors is significant to biological applications, but it is still a great challenging task. Here we first study the binding characteristics of receptor cucurbit[7]uril (CB[7]) to the smallest aromatic tripeptides X1GG (X1 = tryptophan (W), phenylalanine (F), and tyrosine (Y)) and basic tripeptides X2GG (X2 = arginine (R), lysine (K), and histidine (H)) by molecular dynamics simulations. The study indicates that the sidechains of aromatic X1 residues can be encapsulated into the CB[7] cavity, while the sidechains of basic X2 residues prefer to locate at the CB[7] portal. Based on that, we consider hydrophobic aromatic residues as the N-terminus, the smallest glycine (G) as the 2nd-residue and basic residues as the C-terminus, and design nine tripeptides X1GX2 (X1 = F, Y, W and X2 = H, K, R). We found that there is a great influence of the C-terminal basic residue of X1GX2 on binding with CB[7] due to the introduction of a new binding site between CB[7] and the sidechain of the C-terminal residue. Interestingly, CB[7] can differentiate WGR and WGK with similar structures efficiently because of their eight orders of magnitude difference in the association constant (Ka). Besides, for WGR, YGR, and YGK with a nanomolar binding affinity (Ka > 109 M-1), on reversing the sequence order of the 2nd-residue and 3rd-residue, their Ka reduces by about at least 1000-fold, implying the sequence dependence of CB[7] on recognizing these tripeptides. These results predict the potential applications of CB[7] in recognizing cationic amphipathic peptides.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Oligopeptídeos/química , Tensoativos/química , Cátions , Simulação de Dinâmica Molecular , Soluções , Água/química
15.
Nano Lett ; 19(6): 3548-3562, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31026397

RESUMO

Metastasis is the major cause of high mortality in cancer patients; thus, blocking the metastatic process is of critical importance for cancer treatments. The premetastatic niche, a specialized microenvironment with aberrant changes related to inflammation, allows the colonization of circulating tumor cells (CTCs) and serves as a potential target for metastasis prevention. However, little effort has been dedicated to developing nanomedicine to amend the premetastatic niche. Here this study reports a premetastatic niche-targeting micelle for the modulation of premetastatic microenvironments and suppression of tumor metastasis. The micelles are self-assembled with the oleate carbon chain derivative of metformin and docosahexaenoic acid, two anti-inflammatory agents with low toxicity, and coated with fucoidan for premetastatic niche-targeting. The obtained functionalized micelles (FucOMDs) exhibit an excellent blood circulation profile and premetastatic site-targeting efficiency, inhibit CTC adhesion to activated endothelial cells, alleviate lung vascular permeability, and reverse the aberrant expression of key marker proteins in premetastatic niches. As a result, FucOMDs prevent metastasis formation and efficiently suppress both primary-tumor growth and metastasis formation when combined with targeted chemotherapy. Collectively, the findings here provide proof of concept that the modulation of the premetastatic niche with targeted anti-inflammatory agents provides a potent platform and a safe and clinical translational option for the suppression of tumor metastasis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Metformina/administração & dosagem , Metástase Neoplásica/prevenção & controle , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Animais , Anti-Inflamatórios/sangue , Anti-Inflamatórios/uso terapêutico , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Docosa-Hexaenoicos/uso terapêutico , Pulmão/irrigação sanguínea , Metformina/sangue , Metformina/uso terapêutico , Camundongos , Micelas , Metástase Neoplásica/patologia , Neoplasias/patologia , Células Neoplásicas Circulantes/efeitos dos fármacos , Células Neoplásicas Circulantes/patologia , Ratos Sprague-Dawley
16.
BMC Neurol ; 17(1): 44, 2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28231826

RESUMO

BACKGROUND: In recent years, multilevel spinal cord injuries (SCIs) have gained a substantial amount of attention from clinicians and researchers. Multilevel noncontinuous SCI patients cannot undergo the multiple steps of a one-stage operation because of a poor general condition or a lack of proper surgical approaches. The surgeon subsequently faces the decision of whether to initially relieve the rostral or caudal compression. In this study, we established a spinal cord compression model involving two noncontinuous segments in rabbits to evaluate the effects of differences in decompression order on the functional recovery of the spinal cord. METHODS: A Fogarty catheter was inserted into the epidural space through a hole in T6-7 and advanced 3 cm rostrally or caudally. Following successful model establishment, which was demonstrated by an evaluation of evoked potentials, balloons of different volumes (40 µl or 50 µl) were inflated in the experimental groups, whereas no balloons were inflated in the control group. The experimental groups underwent the first decompression in the rostral or caudal area at 1 week post-injury; the second decompression was performed at 2 weeks post-injury. For 6 weeks post-injury, the animals were tested to determine behavioral scores, somatosensory evoked potentials (SEPs) and radiographic imaging changes; histological and apoptosis assay results were subsequently analyzed. RESULTS: The behavioral test results and onset latency of the SEPs indicated that there were significant differences between priority rostral decompression (PRD) and priority caudal decompression (PCD) in the 50-µl compression group at 6 weeks post-injury; however, there were no significant differences between the two procedures in the 40-µl group at the same time point. Moreover, there were no significant peak-to-peak amplitude differences between the two procedures in the 50-µl compression group. CONCLUSIONS: The findings of this study suggested that preferential rostral decompression was more beneficial than priority caudal decompression with respect to facilitating spinal cord functional recovery in rabbits with severe paraplegia and may provide clinicians with a reference for the clinical treatment of multiple-segment spinal cord compression injuries.


Assuntos
Descompressão Cirúrgica/métodos , Compressão da Medula Espinal/cirurgia , Animais , Apoptose , Potenciais Somatossensoriais Evocados/fisiologia , Feminino , Masculino , Coelhos , Radiografia , Recuperação de Função Fisiológica/fisiologia , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Medula Espinal/fisiologia , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/patologia , Compressão da Medula Espinal/fisiopatologia
17.
Am J Physiol Cell Physiol ; 310(4): C305-17, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26879375

RESUMO

We previously found hydrogen sulfide (H2S) to be a new proangiogenic factor. However, the mechanisms underlying the cardiovascular effect of this small gas molecule remain largely unknown. The aim of the present study was to identify the essential microRNAs (miRNAs) involved in the transduction of H2S signals in vascular endothelial cells (ECs). The expression of miR-640 and its signaling elements, vascular endothelial growth factor receptor 2 (VEGFR2), hypoxia inducible factor 1-α (HIF1A), and mammalian target of rapamycin (mTOR), was measured using quantitative PCR and Western blotting. Overexpression and inhibition of miR-640 were performed to clarify their roles in mediating the effect of H2S. In addition, knockdown of VEGFR2, HIF1A, and mTOR was performed using siRNAs, dominant negative mutants, or inhibitors to examine their roles in the transduction of the H2S signals. miR-640 levels decreased in vascular ECs that were treated with H2S, whereas overexpression of miR-640 blunted the proangiogenic effect of H2S. Knockdown of either VEGFR2 or mTOR blunted the downregulation of miR-640 and the proangiogenic effect induced by H2S. In addition, miR-640 bound to the 3'-UTR of HIF1A mRNA and then inhibited the expression of HIF1A. The inhibition could be recovered by treating cells with H2S. Thus we concluded that miR-640 plays a pivotal role in mediating the proangiogenic effect of H2S; H2S acts through downregulation of the expression of miR-640 and increasing the levels of HIF1A through the VEGFR2-mTOR pathway.


Assuntos
Indutores da Angiogênese/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , MicroRNAs/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Regiões 3' não Traduzidas , Sítios de Ligação , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/genética , Mutação , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética , Transfecção , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
18.
Biochem Biophys Res Commun ; 473(4): 931-938, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27055593

RESUMO

In this work, we demonstrated for the first time that S-propargyl-cysteine (SPRC, also named as ZYZ-802), a novel hydrogen sulfide (H2S)-releasing compound, had renoprotective effects on streptozotocin (STZ)-induced diabetic kidney injury. SPRC treatment significantly reduced the level of creatinine, kidney to body weight ratio and in particular, markedly decreased 24-h urine microalbuminuria excretion. SPRC suppressed the mRNA expression of fibronectin and type IV collagen. In vitro, SPRC inhibited mesangial cells over-proliferation and hypertrophy induced by high glucose. Additionally, SPRC attenuated inflammation in diabetic kidneys. SPRC also reduced transforming growth factor ß1 (TGF-ß1) signaling and expression of phosphorylated Smad3 (p-Smad3) pathway. Moreover, SPRC inhibited phosphorylation of ERK, p38 protein. Taken together, SPRC was demonstrated to be a potential therapeutic candidate to suppress diabetic nephropathy.


Assuntos
Cisteína/análogos & derivados , Nefropatias Diabéticas/prevenção & controle , Animais , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Células Cultivadas , Cisteína/farmacologia , Cisteína/uso terapêutico , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/fisiopatologia , Matriz Extracelular/metabolismo , Sulfeto de Hidrogênio/sangue , Sulfeto de Hidrogênio/metabolismo , Rim/metabolismo , Rim/patologia , Rim/fisiopatologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Células Mesangiais/citologia , Células Mesangiais/efeitos dos fármacos , Nefrite/tratamento farmacológico , Nefrite/patologia , Ratos Sprague-Dawley , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/fisiologia
19.
Clin Chim Acta ; 554: 117760, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38176521

RESUMO

Pseudomonas aeruginosa, a common Gram-negative bacterium, is associated with diverse diseases. Its increasing resistance to antibiotics presents challenges in clinical treatment. The predominant diagnostic approach involves conventional biochemical cultures, known for their time and labor intensiveness. Despite progress in isothermal amplification studies, limitations persist, including reliance on specialized equipment, intricate primer design, and aerosol contamination. Therefore, there is a demand for enhanced clinical assays. This study successfully combined RPA and CRISPR/Cas12a techniques. Through a series of experiments involving the design and screening of lasB crRNA, the creation of lasB RPA primers, and the establishment of a streamlined RPA-CRISPR/Cas12a assay, the study developed a one-tube detection method targeting P. aeruginosa's lasB gene. The assay demonstrated inclusive behavior across standard and 21 isolates, while specifically discerning P. aeruginosa from diverse strains. Sensitivity reached 15.9 CFU/reaction. Clinical validation revealed a 97.62% concordance with traditional methods. The one-tube assay's protocol mitigated aerosol contamination. Offering precision, specificity, and sensitivity, this method shows promise for field applications in resource-scarce regions, enabling early detection and improved management of P. aeruginosa infections.


Assuntos
Pseudomonas aeruginosa , Recombinases , Humanos , Pseudomonas aeruginosa/genética , Sistemas CRISPR-Cas/genética , Nucleotidiltransferases , Tecnologia , Aerossóis , Técnicas de Amplificação de Ácido Nucleico
20.
Int Immunopharmacol ; 127: 111335, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38101222

RESUMO

Sepsis is a clinical syndrome triggered by an imbalanced host response to pathogens that can lead to multiple organ dysfunction. The immune response and barrier function of the gut play an important role in the pathogenesis and progression of sepsis. This study aimed to explore the potential role of natural alkaloid Liensinine in the treatment of intestinal injury caused by sepsis and its possible molecular mechanism. In this study, a mouse model of sepsis was established by injecting LPS to explore the protective effect of Liensinine on intestinal injury in sepsis. The results showed that Liensinine could reduce the intestinal damage caused by LPS and increase the number of goblet cells. Furthermore, it decreased the release of inflammatory cytokines by inhibiting NF-kB phosphorylation and NLRP3 inflammasome synthesis. Liensinine also reduced the oxidative stress and ROS accumulation caused by LPS, and played an anti-oxidative stress role by regulating the Nrf2/keap1 signaling pathway. In addition, Liensinine alleviated the inhibition of intestinal autophagy caused by LPS by inhibiting the PI3K/Akt/mTOR pathway. And then it reduced the excessive apoptosis of intestinal cells. This study provides valuable insights for sepsis prevention and treatment, offering a potential therapeutic candidate to protect against intestinal injury and regulate the inflammatory response in sepsis.


Assuntos
Isoquinolinas , Fenóis , Fosfatidilinositol 3-Quinases , Sepse , Camundongos , Animais , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Lipopolissacarídeos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Inflamação/tratamento farmacológico , Apoptose
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