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1.
Eur J Pharmacol ; 974: 176630, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38692426

RESUMEN

Osteoporosis is the most common bone disorder, in which an imbalance between osteoclastic bone resorption and osteoblastic bone formation disrupts bone homeostasis. Osteoporosis management using anti-osteoclastic agents is a promising strategy; however, this remains an unmet need. Sphingosine-1-phosphate (S1P) and its receptors (S1PRs) are essential for maintaining bone homeostasis. Here, we identified that Siponimod, a Food and Drug Administration-approved S1PR antagonist for the treatment of multiple sclerosis, shows promising therapeutic effects against osteoporosis by inhibiting osteoclast formation and function. We found that Siponimod inhibited osteoclast formation in a dose-dependent manner without causing cytotoxicity. Podosome belt staining and bone resorption assays indicated that Siponimod treatment impaired osteoclast function. Western blot and qPCR assays demonstrated that Siponimod suppressed the expression of osteoclast-specific markers, including C-Fos, Nftac1, and Ctsk. Mechanistically, we validated that Siponimod downregulated receptor activator of nuclear factor kappa B ligand (RANKL)-induced Mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways during osteoclastogenesis. Moreover, in a preclinical mouse model, Siponimod prevented ovariectomy-induced bone loss by suppressing osteoclast activity in vivo. Collectively, these results suggest that Siponimod could serve as an alternative therapeutic agent for the treatment of osteoporosis.


Asunto(s)
Azetidinas , Compuestos de Bencilo , Reposicionamiento de Medicamentos , Esclerosis Múltiple , Osteoclastos , Osteoporosis , Animales , Ratones , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Compuestos de Bencilo/farmacología , Compuestos de Bencilo/uso terapéutico , Azetidinas/farmacología , Azetidinas/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Femenino , Moduladores de los Receptores de fosfatos y esfingosina 1/farmacología , Moduladores de los Receptores de fosfatos y esfingosina 1/uso terapéutico , Osteogénesis/efectos de los fármacos , FN-kappa B/metabolismo , Ratones Endogámicos C57BL , Células RAW 264.7 , Resorción Ósea/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Ligando RANK/metabolismo , Humanos
2.
ChemSusChem ; : e202400732, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38661456

RESUMEN

Covalent organic frameworks (COFs) and their applications in photocatalysis have been extensively studied, but the instability of imine-linked COFs is an important factor limiting their performance. In this work, two imine-linked COFs were successfully converted to amide-linked COFs through post synthetic modification (PSM). The oxidized COFs presented lower binding energy to O2, exhibited higher photocatalytic activity for oxidation of thioethers and coupling of benzylamines with excellent stability. The present work can serve as a reliable reference for the development of novel highly active and stable COF-based photocatalysts.

3.
Bioorg Chem ; 147: 107354, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599054

RESUMEN

Pregnane X receptor (PXR) has been considered as a promising therapeutic target for cholestasis due to its crucial regulation in bile acid biosynthesis and metabolism. To search promising natural PXR agonists, the PXR agonistic activities of five traditional Chinese medicines (TCMs) with hepatoprotective efficacy were assayed, and Hypericum japonicum as the most active one was selected for subsequent phytochemical investigation, which led to the isolation of eight nonaromatic acylphloroglucinol-terpenoid adducts including seven new compounds (1 - 4, 5a, 5b and 6). Their structures including absolute configurations were determined by comprehensive spectroscopic, computational and X-ray diffraction analysis. Meanwhile, the PXR agonistic activities of aplenty compounds were evaluated via dual-luciferase reporter assay, RT-qPCR and immunofluorescence. Among them, compounds 1 - 4 showed more potent activity than the positive drug rifampicin. Furthermore, the molecular docking revealed that 1 - 4 were docked well on the PXR ligand binding domain and formed hydrogen bonds with amino acid residues Gln285, Ser247 and His409. This investigation revealed that H. japonicum may serve as a rich source of natural PXR agonists.


Asunto(s)
Hypericum , Simulación del Acoplamiento Molecular , Floroglucinol , Receptor X de Pregnano , Hypericum/química , Receptor X de Pregnano/agonistas , Receptor X de Pregnano/metabolismo , Humanos , Floroglucinol/farmacología , Floroglucinol/química , Floroglucinol/análogos & derivados , Relación Estructura-Actividad , Estructura Molecular , Terpenos/farmacología , Terpenos/química , Terpenos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Células Hep G2
4.
J Am Chem Soc ; 146(15): 10687-10698, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38578843

RESUMEN

Perfluorooctanoic acid (PFOA) is an artificial chemical of global concern due to its high environmental persistence and potential human health risk. Electrochemical methods are promising technologies for water treatment because they are efficient, cheap, and scalable. The electrochemical reduction of PFOA is one of the current methodologies. This process leads to defluorination of the carbon chain to hydrogenated products. Here, we describe a mechanistic study of the electrochemical reduction of PFOA in gold electrodes. By using linear sweep voltammetry (LSV), an E0' of -1.80 V vs Ag/AgCl was estimated. Using a scan rate diagnosis, we determined an electron-transfer coefficient (αexp) of 0.37, corresponding to a concerted mechanism. The strong adsorption of PFOA into the gold surface is confirmed by the Langmuir-like isotherm in the absence (KA = 1.89 × 1012 cm3 mol-1) and presence of a negative potential (KA = 3.94 × 107 cm3 mol-1, at -1.40 V vs Ag/AgCl). Based on Marcus-Hush's theory, calculations show a solvent reorganization energy (λ0) of 0.9 eV, suggesting a large electrostatic repulsion between the perfluorinated chain and water. The estimated free energy of the transition state of the electron transfer (ΔG‡ = 2.42 eV) suggests that it is thermodynamically the reaction-limiting step. 19F - 1H NMR, UV-vis, and mass spectrometry studies confirm the displacement of fluorine atoms by hydrogen. Density functional theory (DFT) calculations also support the concerted mechanism for the reductive defluorination of PFOA, in agreement with the experimental values.

5.
Infect Drug Resist ; 17: 1051-1071, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505247

RESUMEN

Purpose: Bloodstream infection(BSI) is linked with high mortality, underscoring the significance of prompt etiological diagnosis for timely and precise treatment. This study aims to investigate the diagnostic value of droplet digital polymerase chain reaction(ddPCR) in combination with conventional inflammatory markers [interleukin-6(IL-6) and procalcitonin(PCT)] concerning disease progression and treatment prognosis in BSI patients. Furthermore, the study aims to explore a more efficient clinical application strategy. Patients and Methods: This prospective case seried study centers on 176 patients suspected of or confirmed with BSI. Blood samples were collected to extract nucleic acids for identifying pathogens (bacteria, fungi, and viruses) and determining copy loads via ddPCR. Results: The sensitivity of ddPCR was markedly higher compared to the culture method (74.71% vs 31.03%). A positive correlation existed between bacterial load and levels of inflammatory markers [IL-6 (P=0.0182), PCT (P=0.0029), and CRP (P=0.0005)]. In suspected BSI cases, the combination of ddPCR and inflammatory markers could predict sepsis risk [ROC: Area under the curve(AUC)=0.6071, P=0.0383]. Within confirmed BSI patients, the ddPCR bacterial load of those with SOFA<7 was lower than that of the SOFA≥7 (P=0.0334). ddPCR (OR: 1.789, P=0.035) monitoring combined with PCT (OR: 1.787, P=0.035) holded predictive value for SOFA progression (AUC=0.7913, P=0.0003). Similarly, BSI survivors displayed a lower burden than non-survivors (P=0.0170). Additionally, ddPCR combinated with IL-6 provided a more accurate and expedited insight into clinical outcomes prediction for BSI confirmed patients (AUC=0.7352, P=0.0030). Serial monitoring of bacterial load by ddPCR effectively mirrored the clinical course of BSI in patients. Notably, patients with positive ddPCR virus infection exhibited significantly reduced lymphocyte counts (P=0.0003). Conclusion: In a clinical context, qualitative ddPCR results and quantitative continuous monitoring can more precisely assess sepsis progression and treatment prognosis in BSI patients. Furthermore, ddPCR results offer quicker and more accurate reference points for clinical antibacterial and antiviral interventions.

6.
Nat Prod Res ; : 1-8, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436324

RESUMEN

Phytochemical investigation on the plant endophytic fungus Penicillium ferraniaense GE-7 led to the isolation of 18 compounds including one new α-pyrone derivative, peniferranige A (1). The structure including the absolute configuration of compound 1 was elucidated by NMR, HRMS, and ECD data. Demethoxyfumitremorgin C (16) and meleagrin (17) possessed moderate activities against the human lung cancer cell line H1975 with IC50 values of 28.52 ± 1.07 and 13.94 ± 1.92 µM, respectively.

7.
Microbiol Res ; 282: 127626, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38330817

RESUMEN

Bloodstream infection (BSI) refers to the infection of blood by pathogens. Severe immune response to BSI can lead to sepsis, a systemic infection leading to multiple organ dysfunction, coupled with drug resistance, mortality, and limited clinical treatment options. This work aims to further investigate the new interplay between bacterial exocrine regulatory protein and host immune cells in the context of highly drug-resistant malignant BSI. Whether interfering with related regulatory signaling pathways can reverse the inflammatory disorder of immune cells. In-depth analysis of single-cell sequencing results in Septic patients for potential immunodeficiency factors. Analysis of key proteins enriched by host cells and key pathways using proteomics. Cell models and animal models validate the pathological effects of DnaK on T cells, MAITs, macrophages, and osteoclasts. The blood of patients was analyzed for the immunosuppression of T cells and MAITs. We identified that S. maltophilia-DnaK was enriched in immunodeficient T cells. The activation of the JAK2/STAT1 axis initiated the exhaustion of T cells. Septic patients with Gram-negative bacterial infections exhibited deficiencies in MAITs, which correspond to IFN-γ. Cellular and animal experiments confirmed that DnaK could facilitate MAIT depletion and M1 polarization of macrophages. Additionally, Fludarabine mitigated M1 polarization of blood, liver, and spleen in mice. Interestingly, DnaK also repressed osteoclastogenesis of macrophages stimulated by RANKL. S.maltophilia-DnaK prompts the activation of the JAK2/STAT1 axis in T cells and the M1 polarization of macrophages. Targeting the DnaK's crosstalk can be a potentially effective approach for treating the inflammatory disorder in the broad-spectrum drug-resistant BSI.


Asunto(s)
Antiinfecciosos , Sepsis , Humanos , Animales , Ratones , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Macrófagos , Hígado , Antiinfecciosos/metabolismo , Proteínas Bacterianas/metabolismo , Linfocitos T/metabolismo , Factor de Transcripción STAT1/metabolismo , Janus Quinasa 2/metabolismo
8.
Chem Commun (Camb) ; 60(22): 3047-3050, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38376492

RESUMEN

A novel AIEgen molecular probe (N-3QL) with typical AIE effects, good biocompatibility, lysosome targeting, pH activation, excellent photostability, and high brightness was synthesized using two simple synthetic steps. Spectroscopic and cytotoxicity experiments indicate that N-3QL can not only be used for the dynamic monitoring of cancer cell lysosomes, but also for photodynamic therapy (PDT) ablation of cancer cells.


Asunto(s)
Fotoquimioterapia , Fotoquimioterapia/métodos , Sondas Moleculares/análisis , Concentración de Iones de Hidrógeno , Lisosomas/química
9.
Nat Commun ; 15(1): 1402, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365867

RESUMEN

High or medium- entropy alloys (HEAs/MEAs) are multi-principal element alloys with equal atomic elemental composition, some of which have shown record-breaking mechanical performance. However, the link between short-range order (SRO) and the exceptional mechanical properties of these alloys has remained elusive. The local destruction of SRO by dislocation glide has been predicted to lead to a rejuvenated state with increased entropy and free energy, creating softer zones within the matrix and planar fault boundaries that enhance the ductility, but this has not been verified. Here, we integrate in situ nanomechanical testing with energy-filtered four-dimensional scanning transmission electron microscopy (4D-STEM) and directly observe the rejuvenation during cyclic mechanical loading in single crystal CrCoNi at room temperature. Surprisingly, stacking faults (SFs) and twin boundaries (TBs) are reversible in initial cycles but become irreversible after a thousand cycles, indicating SF energy reduction and rejuvenation. Molecular dynamics (MD) simulation further reveals that the local breakdown of SRO in the MEA triggers these SF reversibility changes. As a result, the deformation features in HEAs/MEAs remain planar and highly localized to the rejuvenated planes, leading to the superior damage tolerance characteristic in this class of alloys.

11.
Int J Genomics ; 2024: 4123737, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38352691

RESUMEN

The mesenchymal feature, dominated by epithelial mesenchymal transition (EMT) and stromal cell activation, is one of the main reasons for the aggressive nature of tumors, yet it remains poorly understood. In gastric cancer (GC), the fermitin family homolog-2 (FERMT2) is involved in macrophage signaling, promoting migration and invasion. However, the function of FERMT2 in fibroblasts remains unclear. Here, we demonstrated that downregulation of FERMT2 expression can block EMT in GC cells by inhibiting fibroblast activation in vitro. Furthermore, we found that, in addition to the known pathways, fibroblast-derived FERMT2 promotes M2-like macrophage growth and that in human GC samples, there is a strong positive correlation between FERMT2 and CD163 and CD206 levels. Notably, high FERMT2 expression was significantly associated with poor clinical outcomes and was upregulated in patients with advanced disease. Taken together, our results provide evidence that the fibroblast-FERMT2-EMT-M2 macrophage axis plays a critical role in the GC mesenchymal phenotype and may be a promising target for the treatment of advanced GC.

12.
Adv Sci (Weinh) ; 11(13): e2307850, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240457

RESUMEN

Kidney fibrosis is a common fate of chronic kidney diseases (CKDs), eventually leading to renal dysfunction. Yet, no effective treatment for this pathological process has been achieved. During the bioassay-guided chemical investigation of the medicinal plant Wikstroemia chamaedaphne, a daphne diterpenoid, daphnepedunin A (DA), is characterized as a promising anti-renal fibrotic lead. DA shows significant anti-kidney fibrosis effects in cultured renal fibroblasts and unilateral ureteral obstructed mice, being more potent than the clinical trial drug pirfenidone. Leveraging the thermal proteome profiling strategy, cell division cycle 42 (Cdc42) is identified as the direct target of DA. Mechanistically, DA targets to reduce Cdc42 activity and down-regulates its downstream phospho-protein kinase Cζ(p-PKCζ)/phospho-glycogen synthase kinase-3ß (p-GSK-3ß), thereby promoting ß-catenin Ser33/37/Thr41 phosphorylation and ubiquitin-dependent proteolysis to block classical pro-fibrotic ß-catenin signaling. These findings suggest that Cdc42 is a promising therapeutic target for kidney fibrosis, and highlight DA as a potent Cdc42 inhibitor for combating CKDs.


Asunto(s)
Diterpenos , Enfermedades Renales , Proteína de Unión al GTP cdc42 , Animales , Ratones , beta Catenina/efectos de los fármacos , beta Catenina/metabolismo , Fibrosis/tratamiento farmacológico , Glucógeno Sintasa Quinasa 3 beta/efectos de los fármacos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Riñón/metabolismo , Enfermedades Renales/tratamiento farmacológico , Wikstroemia/química , Diterpenos/farmacología , Proteína de Unión al GTP cdc42/efectos de los fármacos
13.
BMC Plant Biol ; 24(1): 28, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38172675

RESUMEN

BACKGROUND: Canopy architecture is critical in determining the fruit-zone microclimate and, ultimately, in determining an orchard's success in terms of the quality and quantity of the fruit produced. However, few studies have addressed how the canopy environment leads to metabolomic and transcriptomic alterations in fruits. Designing strategies for improving the quality of pear nutritional components relies on uncovering the related regulatory mechanisms. RESULTS: We performed an in-depth investigation of the impact of canopy architecture from physiological, metabolomic and transcriptomic perspectives by comparing pear fruits grown in a traditional freestanding system (SP) or a flat-type trellis system (DP). Physiological studies revealed relatively greater fruit sizes, soluble solid contents and titratable acidities in pear fruits from DP systems with open canopies. Nontargeted metabolite profiling was used to characterize fruits at the initial ripening stage. Significant differences in fruit metabolites, including carbohydrates, nucleic acids, alkaloids, glycerophospholipids, sterol lipids, and prenol lipids, were observed between the two groups. Transcriptomic analysis indicated that a series of organic substance catabolic processes (e.g., the glycerol-3-phosphate catabolic process, pectin catabolic process and glucan catabolic process) were overrepresented in fruits of the DP system. Moreover, integrative analysis of the metabolome and transcriptome at the pathway level showed that DP pear fruits may respond to the canopy microenvironment by upregulating phenylpropanoid biosynthesis pathway genes such as PpPOD. Transient assays revealed that the contents of malic acid and citric acid were lower in the pear flesh of PpPOD RNAi plants, which was associated with regulating the expression of organic acid metabolism-related genes. CONCLUSIONS: Our results provide fundamental evidence that at the physiological and molecular levels, open-canopy architecture contributes to improving pear fruit quality and is correlated with increased levels of carbohydrates and lipid-like molecules. This study may lead to the development of rational culture practices for enhancing the nutritional traits of pear fruits.


Asunto(s)
Pyrus , Frutas , Proteínas de Plantas/genética , Perfilación de la Expresión Génica , Carbohidratos , Lípidos , Regulación de la Expresión Génica de las Plantas
14.
Int Immunopharmacol ; 128: 111490, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38218008

RESUMEN

BACKGROUND AND OBJECTIVES: Ulcerative colitis (UC) is a recurrent intestinal inflammatory disease which poses a serious threat to the life of patients. However, there are no specific drugs for UC yet. Hypericum sampsonii Hance (HS) is a Chinese herbal medicine traditionally used to treat enteritis and dysentery. Our previous studies have demonstrated that HS holds potential anti-UC effects, and a novel compound named Hypersampsonone H (HS-1) isolated from HS possesses significant anti-inflammatory activity. However, the beneficial effects of HS-1 on UC remain unclear. This study aimed to investigate the therapeutic effects of HS-1 on UC and its potential mechanisms, both in vitro and in vivo. METHODS: The in vitro model was employed using LPS-induced RAW264.7 cells to investigate the anti-inflammatory effects of HS-1 and its possible mechanisms. Furthermore, the therapeutic efficacy and potential mechanisms of HS-1 against dextran sulfate sodium (DSS)-induced acute colitis were assessed through histopathological examination, biochemical analysis, and molecular docking. RESULTS: In vitro, HS-1 significantly reduced LPS-induced inflammatory responses, as indicated by inhibiting NO production, down-regulating the overexpression of COX-2 and iNOS, as well as regulating the imbalanced levels of IL-6, TNF-α, and IL-10. Moreover, HS-1 also inhibited the expression of PDE4, elevated the intracellular cAMP level, and promoted the phosphorylation of CREB, thereby activating the PKA/CREB pathway in RAW264.7 cells. In vivo, HS-1 demonstrated therapeutic capacity against DSS-induced colitis by alleviating the symptoms of colitis mice, regulating the abnormal expression of inflammatory mediators, protecting the integrity of intestinal epithelial barrier, and reducing tissue fibrosis. Consistently, HS-1 was found to decrease the expression of PDE4 isoforms, subsequently activating the cAMP/PKA/CREB signaling pathway. Furthermore, the molecular docking results indicated that HS-1 exhibited a high affinity for PDE4, particularly PDE4D. Further mechanistic validation in vitro demonstrated that HS-1 possessed a synergistic effect on forskolin and an antagonistic effect on H-89 dihydrochloride, thereby exerting anti-inflammatory effects through the cAMP/PKA/CREB signaling pathway. CONCLUSION: We disclose that HS-1 serves as a promising candidate drug for the treatment of UC by virtue of its ability to reduce DSS-induced colitis via the inhibition of PDE4 and the activation of cAMP/PKA/CREB signaling pathway.


Asunto(s)
Colitis Ulcerosa , Colitis , Humanos , Ratones , Animales , Colitis Ulcerosa/tratamiento farmacológico , Lipopolisacáridos/farmacología , Simulación del Acoplamiento Molecular , Transducción de Señal , Colitis/inducido químicamente , Antiinflamatorios/uso terapéutico , Sulfato de Dextran/farmacología , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Colon/patología
15.
Nat Prod Res ; 38(6): 986-993, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37157835

RESUMEN

Phytochemical investigation on the plant of Wikstroemia alternifolia led to the isolation of 26 compounds including two new ones, wikstralternifols A and B (1 and 7). Their structures including the absolute configuration were elucidated by spectroscopic data together with analysis of experimental and calculated ECD data. All compounds were isolated from this plant for the first time, and their main structural types were lignans, sesquiterpenoids, and flavonoids. In the sodium nitroprusside-induced rat pheochromocytoma PC-12 cell model, the neuroprotective activities of the selected sesquiterpenoids (1 and 4) and lignans (7 - 14) were screened at the concentration of 10 µM, and 7 - 14 displayed better activities than the positive control edaravone.


Asunto(s)
Lignanos , Sesquiterpenos , Wikstroemia , Wikstroemia/química , Lignanos/farmacología , Lignanos/química , Flavonoides/farmacología , Plantas , Sesquiterpenos/química , Estructura Molecular
16.
Bioorg Chem ; 143: 106977, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38064805

RESUMEN

It is reported that panaxadiol has neuroprotective effects. Previous studies have found that compound with carbamate structure introduced at the 3-OH position of 20 (R) -panaxadiol showed the most effective neuroprotective activity with an EC50 of 13.17 µM. Therefore, we designed and synthesized a series of ginseng diol carbamate derivatives with ginseng diol as the lead compound, and tested their anti-AD activity. It was found that the protective effect of compound Q4 on adrenal pheochromocytoma was 80.6 ±â€¯10.85 % (15 µM), and the EC50 was 4.32 µM. According to the ELISA results, Q4 reduced the expression of Aß25-35 by decreasing ß-secretase production. Molecular docking studies revealed that the binding affinity of Q4 to ß-secretase was -49.67 kcal/mol, indicating a strong binding affinity of Q4 to ß-secretase. Western blotting showed that compound Q4 decreased IL-1ß levels, which may contribute to its anti-inflammatory effect. Furthermore, compound Q4 exhibits anti-AD activities by reducing abnormal phosphorylation of tau protein and activation of the mitogen activated protein kinase pathway. The learning and memory deficits in mice treated with Q4in vivo were significantly alleviated. Therefore, Q4 may be a promising multifunctional drug for the treatment of AD, providing a new way for anti-AD drugs.


Asunto(s)
Enfermedad de Alzheimer , Ginsenósidos , Fármacos Neuroprotectores , Ratones , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Simulación del Acoplamiento Molecular , Carbamatos/química , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico
17.
Biomater Sci ; 12(3): 564-580, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-37975197

RESUMEN

Biomacromolecules, such as proteins, nucleic acids and polysaccharides, are widely distributed in the human body, and some of them have been recognized as the targets of drugs for disease theranostics. Drugs typically act on targets in two ways: non-covalent bond and covalent bond. Non-covalent bond-based drugs have some disadvantages, such as structural instability and environmental sensitivity. Covalent interactions between drugs and targets have a longer action time, higher affinity and controllability than non-covalent interactions of conventional drugs. With the development of artificial intelligence, covalent drugs have received more attention and have been developed rapidly in pharmaceutical research in recent years. From the perspective of covalent drugs, this review summarizes the design methods and the effects of covalent drugs. Finally, we discuss the application of covalent peptide drugs and expect to provide a new reference for cancer treatment.


Asunto(s)
Ácidos Nucleicos , Medicina de Precisión , Humanos , Inteligencia Artificial , Péptidos , Proteínas/química , Ácidos Nucleicos/química
18.
Neural Netw ; 170: 564-577, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38056406

RESUMEN

Demystifying the interactions among multiple agents from their past trajectories is fundamental to precise and interpretable trajectory prediction. However, previous works mainly consider static, pairwise interactions with limited relational reasoning. To more comprehensively model interactions and reason relations, we propose DynGroupNet, a dynamic-group-aware network, which (i) models time-varying interactions in highly dynamic scenes; (ii) captures both pairwise and group-wise interactions; and (iii) reasons both interaction strength and category without direct supervision. Based on DynGroupNet, we further design a prediction system to forecast socially plausible trajectories with dynamic relational reasoning. The proposed prediction system leverages the Gaussian mixture model, multiple sampling and prediction refinement to promote prediction diversity for multiple future possibilities capturing, training stability for efficient model learning and trajectory smoothness for more realistic predictions, respectively. The proposed complex interaction modeling of DynGroupNet, future diversity capturing, efficient model training and trajectory smoothing of prediction system together to promote more accurate and plausible future predictions. Extensive experiments show that: (1) DynGroupNet can capture time-varying group behaviors, infer time-varying interaction category and interaction strength during prediction; (2) DynGroupNet significantly outperforms the state-of-the-art trajectory prediction methods by 28.0%, 34.9%, 13.0% in FDE on the NBA, NFL and SDD datasets.


Asunto(s)
Aprendizaje , Solución de Problemas , Distribución Normal
19.
Phytochemistry ; 217: 113920, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37951561

RESUMEN

Ten lignans, including six previously undescribed phenolic ester glycosyl lignans (1-6), were isolated from a well-known traditional Chinese medicine, Qin-Jiao, which is the dry root of Gentiana macrophylla Pall. (Gentianaceae). Their structures were determined by spectroscopic and chemical methods, especially 2D NMR techniques. Quantum chemical calculations of theoretical ECD spectra allowed the determination of their absolute configurations. Refer to its traditional applications for the treatment of rheumatic arthralgia and hepatopathy, these compounds were evaluated on a TNF-α induced MH7A human synoviocyte inflammation model and a D-GalN induced AML12 hepatocyte injury model. Compounds 1, 2, 5, and 6 significantly reduced the release of proinflammatory cytokine IL-1ß in MH7A cells at 15 µM and they also could strongly protect AML12 cells against D-GalN injury at 30 µM. Flow cytometry and Western blot analysis showed that compound 5 ameliorated D-GalN induced AML12 cell apoptosis by upregulating the expression of anti-apoptotic Bcl-2 protein and down-regulating the expression of pro-apoptotic Bax protein.


Asunto(s)
Medicamentos Herbarios Chinos , Gentiana , Lignanos , Humanos , Gentiana/química , Lignanos/farmacología , Glucósidos/farmacología , Glucósidos/química , Medicamentos Herbarios Chinos/farmacología , Inflamación
20.
Enzyme Microb Technol ; 174: 110381, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38134734

RESUMEN

Indigo, an economically important dye, could be biosynthesized from indole by catalysis of the styrene monooxygenase StyAB. To enhance indigo biosynthesis, the styAB gene and its transcription regulator gene styS/styR in styrene catabolism were cloned from Pseudomonas putida and coexpressed in Escherichia coli. The presence of the intact regulator gene styS/styR dramatically increased the transcriptional levels of styA and styB by approximately 120-fold in the recombinant strain SRAB2 with coexpression of styS/styR and styAB compared to the control strain ABST with solo expression of styAB. A yield of 67.6 mg/L indigo was detected in strain SRAB2 after 24 h of fermentation with 120 µg/mL indole, which was approximately 14-fold higher than that in the control strain ABST. The maximum yield of indigo was produced from 160 µg/mL indole in fermentation of strain SRAB2. However, the addition of styrene to the media significantly inhibited the transcription of styA and styB and consequent indigo biosynthesis in recombinant E. coli strains. Furthermore, the substitution of indole with tryptophan as the fermentation substrate remarkably boosted indigo production, and the maximal yield of 565.6 mg/L was detected in strain SRAB2 in fermentation with 1.2 mg/mL tryptophan. The results revealed that the regulation of styAB transcription by the two-component regulator StyS/StyR in styrene catabolism in P. putida was effective in E. coli, which provided a new strategy for the development of engineered E. coli strains with the capacity for highly efficient indigo production.


Asunto(s)
Escherichia coli , Carmin de Índigo , Escherichia coli/genética , Escherichia coli/metabolismo , Triptófano , Indoles/metabolismo , Estireno/metabolismo , Oxigenasas/genética , Oxigenasas/metabolismo
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