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1.
J Neuroinflammation ; 21(1): 227, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285282

RESUMEN

Cognitive impairment is a common issue among human patients undergoing surgery, yet the neural mechanism causing this impairment remains unidentified. Surgical procedures often lead to glial cell activation and neuronal hypoexcitability, both of which are known to contribute to postoperative cognitive dysfunction (POCD). However, the role of neuron-glia crosstalk in the pathology of POCD is still unclear. Through integrated transcriptomics and proteomics analyses, we found that the complement cascades and microglial phagocytotic signaling pathways are activated in a mouse model of POCD. Following surgery, there is a significant increase in the presence of complement C3, but not C1q, in conjunction with presynaptic elements. This triggers a reduction in excitatory synapses, a decline in excitatory synaptic transmission, and subsequent memory deficits in the mouse model. By genetically knockout out C3ar1 or inhibiting p-STAT3 signaling, we successfully prevented neuronal hypoexcitability and alleviated cognitive impairment in the mouse model. Therefore, targeting the C3aR and downstream p-STAT3 signaling pathways could serve as potential therapeutic approaches for mitigating POCD.


Asunto(s)
Complemento C3 , Modelos Animales de Enfermedad , Trastornos de la Memoria , Ratones Noqueados , Microglía , Animales , Ratones , Microglía/metabolismo , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Complemento C3/metabolismo , Complemento C3/genética , Ratones Endogámicos C57BL , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Receptores de Complemento/metabolismo , Receptores de Complemento/genética , Masculino , Complicaciones Cognitivas Postoperatorias/metabolismo , Complicaciones Cognitivas Postoperatorias/etiología , Sinapsis/metabolismo , Sinapsis/patología , Potenciales Postsinápticos Excitadores/fisiología , Potenciales Postsinápticos Excitadores/efectos de los fármacos
2.
Small ; : e2405533, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212632

RESUMEN

Photocatalysis is a most important approach to addressing global energy shortages and environmental issues due to its environmentally friendly and sustainable properties. The key to realizing efficient photocatalysis relies on developing appropriate catalysts with high efficiency and chemical stability. Among various photocatalysts, Metal-organic frameworks (MOFs)-derived hollow-structured materials have drawn increased attention in photocatalysis based on advantages like more active sites, strong light absorption, efficient transfer of pho-induced charges, excellent stability, high electrical conductivity, and better biocompatibility. Specifically, MOFs-derived hollow-structured materials are widely utilized in photocatalytic CO2 reduction (CO2RR), hydrogen evolution (HER), nitrogen fixation (NRR), degradation, and other reactions. This review starts with the development story of MOFs, the commonly adopted synthesis strategies of MOFs-derived hollow materials, and the latest research progress in various photocatalytic applications are also introduced in detail. Ultimately, the challenges of MOFs-derived hollow-structured materials in practical photocatalytic applications are also prospected. This review holds great potential for developing more applicable and efficient MOFs-derived hollow-structured photocatalysts.

3.
J Nat Prod ; 87(4): 1171-1178, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38557026

RESUMEN

The potential of natural products as pharmaceutical and agricultural agents is based on their large structural diversity, resulting in part from modifications of the backbone structure by tailoring enzymes during biosynthesis. Flavin-dependent monooxygenases (FMOs), as one such group of enzymes, play an important role in the biosynthesis of diverse natural products, including cyclodipeptide (CDP) derivatives. The FMO PboD was shown to catalyze C-3 hydroxylation at the indole ring of cyclo-l-Trp-l-Leu in the biosynthesis of protubonines, accompanied by pyrrolidine ring formation. PboD substrate promiscuity was investigated in this study by testing its catalytic activity toward additional tryptophan-containing CDPs in vitro and biotransformation in Aspergillus nidulans transformants bearing a truncated protubonine gene cluster with pboD and two acetyltransferase genes. High acceptance of five CDPs was detected for PboD, especially of those with a second aromatic moiety. Isolation and structure elucidation of five pyrrolidine diketopiperazine products, with two new structures, proved the expected stereospecific hydroxylation and pyrrolidine ring formation. Determination of kinetic parameters revealed higher catalytic efficiency of PboD toward three CDPs consisting of aromatic amino acids than of its natural substrate cyclo-l-Trp-l-Leu. In the biotransformation experiments with the A. nidulans transformant, modest formation of hydroxylated and acetylated products was also detected.


Asunto(s)
Aspergillus , Dicetopiperazinas , Aspergillus/enzimología , Aspergillus/química , Aspergillus nidulans/enzimología , Aspergillus nidulans/metabolismo , Dicetopiperazinas/química , Dicetopiperazinas/metabolismo , Flavinas/metabolismo , Hidroxilación , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Estructura Molecular , Péptidos Cíclicos/química , Péptidos Cíclicos/metabolismo , Especificidad por Sustrato
4.
J Nat Prod ; 87(4): 966-975, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38441877

RESUMEN

Ten new (1-10) and nine known (11-19) austocystins, along with four known anthraquinones (20-23), were isolated from the culture of Aspergillus ustus NRRL 5856 by bioactivity-guided fractionation. The structures of the new compounds were elucidated by spectroscopic data analysis, X-ray crystallographic study, the modified Mosher's method, [Rh2(OCOCF3)4]-induced ECD spectral analysis, and comparison of the experimental ECD spectra with those of the similar analogues. Compounds 1-8 represent the first examples of austocystins with a C-4' oxygenated substitution. The absolute configuration of 1″-hydroxy austocystin D (11) was determined by single-crystal X-ray diffraction and consideration of its biosynthetic origin. Compounds 5, 9, and 11 exhibited significant inhibitory effects against the proliferation of ConA-induced T cells with IC50 values of 1.1, 1.0, and 0.93 µM, respectively. Furthermore, these compounds suppressed the expression of IL-6 in a dose-dependent manner. Compounds 10-12 and 14 showed pronounced cytotoxicities against MCF-7 with IC50 values of 3.9, 1.3, 0.46, and 2.3 µM, respectively.


Asunto(s)
Aspergillus , Inmunosupresores , Aspergillus/química , Humanos , Inmunosupresores/farmacología , Inmunosupresores/química , Inmunosupresores/aislamiento & purificación , Estructura Molecular , Cristalografía por Rayos X , Interleucina-6/metabolismo , Antraquinonas/farmacología , Antraquinonas/química , Animales , Ensayos de Selección de Medicamentos Antitumorales , Linfocitos T/efectos de los fármacos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Proliferación Celular/efectos de los fármacos
5.
Appl Microbiol Biotechnol ; 108(1): 427, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046587

RESUMEN

Filamentous fungi are prolific producers of bioactive natural products and play a vital role in drug discovery. Yet, their potential cannot be fully exploited since many biosynthetic genes are silent or cryptic under laboratory culture conditions. Several strategies have been applied to activate these genes, with heterologous expression as one of the most promising approaches. However, successful expression and identification of new products are often hindered by host-dependent factors, such as low gene targeting efficiencies, a high metabolite background, or a lack of selection markers. To overcome these challenges, we have constructed a Penicillium crustosum expression host in a pyrG deficient strain by combining the split-marker strategy and CRISPR-Cas9 technology. Deletion of ligD and pcribo improved gene targeting efficiencies and enabled the use of an additional selection marker in P. crustosum. Furthermore, we reduced the secondary metabolite background by inactivation of two highly expressed gene clusters and abolished the formation of the reactive ortho-quinone methide. Finally, we replaced the P. crustosum pigment gene pcr4401 with the commonly used Aspergillus nidulans wA expression site for convenient use of constructs originally designed for A. nidulans in our P. crustosum host strain. As proof of concept, we successfully expressed a single polyketide synthase gene and an entire gene cluster at the P. crustosum wA locus. Resulting transformants were easily detected by their albino phenotype. With this study, we provide a highly efficient platform for heterologous expression of fungal genes. KEY POINTS: Construction of a highly efficient Penicillium crustosum heterologous expression host Reduction of secondary metabolite background by genetic dereplication strategy Integration of wA site to provide an alternative host besides Aspergillus nidulans.


Asunto(s)
Sistemas CRISPR-Cas , Penicillium , Metabolismo Secundario , Penicillium/genética , Penicillium/metabolismo , Metabolismo Secundario/genética , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Familia de Multigenes , Marcación de Gen/métodos , Regulación Fúngica de la Expresión Génica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Vías Biosintéticas/genética , Ingeniería Metabólica/métodos , Expresión Génica
6.
Anesth Analg ; 139(2): 411-419, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38241681

RESUMEN

BACKGROUND: The microglial activation has been implicated in cancer-induced bone pain. Recent studies have revealed that microglia mediate synaptic pruning in the central nervous system, where the cluster of differentiation 47-signal regulatory protein α (CD47-SIRPα) axis creates a "don't eat me" signal and elicits an antiphagocytic effect to protect synapses against elimination. To date, the synaptic phagocytosis in microglia has never been investigated in the murine cancer-induced bone pain model. The present experiments sought to explore whether microglia phagocytize synapses in mice with bone cancer pain as well as the possible mechanisms. METHODS: Male C3H/HeN mice were used to induce bone cancer pain. Minocycline and S-ketamine were injected into D14. The number of spontaneous flinches (NSF) and paw withdrawal mechanical thresholds (PWMT) were measured on D0, D4, D7, D10, D14, D21, and D28. Hematoxylin and eosin staining presented bone lesions. Western blotting examined the Gephyrin, CD47, and SIRPα expression. Flow cytometry evaluated the proportion of SIRPα + cells in the spine. Immunofluorescence and 3-dimensional reconstruction showed the Gephyrin puncta inside microglial lysosomes. RESULTS: Mice embedded with tumor cells induced persistent spontaneous pain and mechanical hyperalgesia. Hematoxylin and eosin staining revealed bone destruction and tumor infiltration in marrow cavities. Microglia underwent a responsive and proliferative burst (t = -16.831, P < .001). Western blotting manifested lowered Gephyrin expression in the tumor group (D4, D7, D10, D14, D21, and D28: P < .001). Immunofluorescence and 3-dimensional reconstruction showed larger volumes of Gephyrin puncta inside microglial lysosomes (t = -23.273, P < .001; t = -27.997, P < .001). Treatment with minocycline or S-ketamine exhibited pain relief and antiphagocytic effects (t = -6.191, P < .001, t = -7.083, P < .001; t = -20.767, P < .001, t = -17.080, P < .001; t = 11.789, P < .001, t = 16.777, P < .001; t = 8.868, P < .001, t = 21.319, P < .001). Last but not least, the levels of CD47 and SIRPα proteins were downregulated (D10: P = .004, D14, D21, and D28: P < .001; D10, D14, D21, and D28: P < .001). Flow cytometry and immunofluorescence substantiated reduced microglial SIRPα (t = 11.311, P < .001; t = 12.189, P < .001). CONCLUSIONS: Microglia-mediated GABAergic synapse pruning in the spinal cord dorsal horn in bone cancer pain mice, which might be associated with the declined CD47-SIRPα signal. Our research uncovered an innovative mechanism that highlighted microglia-mediated synaptic phagocytosis in a murine cancer-induced bone pain model.


Asunto(s)
Neoplasias Óseas , Antígeno CD47 , Dolor en Cáncer , Modelos Animales de Enfermedad , Ratones Endogámicos C3H , Microglía , Fagocitosis , Receptores Inmunológicos , Animales , Microglía/efectos de los fármacos , Microglía/metabolismo , Masculino , Fagocitosis/efectos de los fármacos , Dolor en Cáncer/metabolismo , Dolor en Cáncer/etiología , Dolor en Cáncer/fisiopatología , Neoplasias Óseas/complicaciones , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Ratones , Receptores Inmunológicos/metabolismo , Antígeno CD47/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Asta Dorsal de la Médula Espinal/efectos de los fármacos , Sinapsis/efectos de los fármacos , Sinapsis/patología , Sinapsis/metabolismo , Minociclina/farmacología , Conducta Animal/efectos de los fármacos
7.
J Fish Biol ; 104(1): 44-55, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658731

RESUMEN

The cobia Rachycentron canadum, mainly distributed in the warm waters of tropical and subtropical regions around the world, remains a fish of considerable economic importance. Detailed diversity and the number of microsatellite sequences in the cobia genome are still unintelligible. The primary aim of this work was to identify and quantify the miscellaneous SSR sequences in the cobia genome. More than 280,000 sequences were sequenced and screened using next-generation sequencing technology and microsatellite identification. Perfect mononucleotide repeats, dinucleotide microsatellites, and trinucleotide microsatellites contain (A)10 /(T)10 , (AC)6 /(TG)6 , and (AAT)5-32 as the largest number of motifs in each type of microsatellite, respectively. The tetranucleotide and pentanucleotide microsatellites (TTM and PTM) consist of the largest number of motifs of both (ATCT)5-32 and (TCAT)5-31 in TTMs, and (CTCTC)5-9 in PTMs, whereas the hexanucleotide microsatellites are rarely observed in the cobia genome. All c. 38000 sequences of composite microsatellites are extremely diverse, including compound (11.71%), interrupted compound (71.77%), complex (0.45%), and interrupted complex (16.07%). In this study, we developed a convenient and useful recording system for writing down and categorizing diverse composite microsatellite types. This system will provide great support for exploring repeat origins, evolutionary mechanisms, and the application of polymorphic microsatellites.


Asunto(s)
Genoma , Perciformes , Animales , Repeticiones de Microsatélite , Perciformes/genética , Peces/genética
8.
Chembiochem ; 24(3): e202200502, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36098493

RESUMEN

Secondary metabolites derived from microorganism constitute an important part of natural products. Mining of the microbial genomes revealed a large number of uncharacterized biosynthetic gene clusters, indicating their greater potential to synthetize specialized or secondary metabolites (SMs) than identified by classic fermentation and isolation approaches. Various bioinformatics tools have been developed to analyze and identify such gene clusters, thus accelerating significantly the mining process. Heterologous expression of an individual biosynthetic gene cluster has been proven as an efficient way to activate the genes and identify the encoded metabolites that cannot be detected under normal laboratory cultivation conditions. Herein, we describe a concept of genomics-guided approach by performing genome mining and heterologous expression to uncover novel CDPS-derived DKPs and functionally characterize novel tailoring enzymes embedded in the biosynthetic pathways. Recent works focused on the identification of the nucleobase-related and dimeric DKPs are also presented.


Asunto(s)
Actinobacteria , Productos Biológicos , Actinobacteria/genética , Actinobacteria/metabolismo , Genómica , Dicetopiperazinas , Biología Computacional , Familia de Multigenes , Vías Biosintéticas/genética , Productos Biológicos/metabolismo
9.
J Nat Prod ; 86(7): 1779-1785, 2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37382166

RESUMEN

The hydroxylated and diacetylated cyclo-l-Trp-l-Leu derivative (-)-protubonine B was isolated from a culture of Aspergillus ustus 3.3904. Genome mining led to the identification of a putative biosynthetic gene cluster coding for a bimodular nonribosomal peptide synthetase, a flavin-dependent monooxygenase, and two acetyltransferases. Heterologous expression of the pbo cluster in Aspergillus nidulans showed that it is responsible for the formation of the isolated metabolite. Gene deletion experiments and structural elucidation of the isolated intermediates confirmed the biosynthetic steps. In vitro experiments with the recombinant protein proved that the flavin-dependent oxygenase is responsible for stereospecific hydroxylation at the indole ring accompanied by pyrrolidine ring formation.


Asunto(s)
Aspergillus nidulans , Oxigenasas , Oxigenasas/genética , Hidroxilación , Aspergillus nidulans/genética , Flavinas/genética , Familia de Multigenes
10.
J Nat Prod ; 86(1): 94-102, 2023 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-36599087

RESUMEN

Heterologous expression of a cdps-p450 locus from Streptomyces sp. NRRL S-1521 led to the identification of guanitrypmycin D1, a new guaninylated diketopiperazine. The cytochrome P450 GutD1521 catalyzed the regiospecific transfer of guanine to C-2 of the indole ring of cyclo-(l-Trp-l-Tyr) via a C-C linkage and represents a new chemical transformation within this enzyme class. Furthermore, GutD1521 efficiently accepts several other tryptophan-containing cyclodipeptides or derivatives for regiospecific coupling with guanine, thus generating different guanitrypmycin analogs.


Asunto(s)
Streptomyces , Streptomyces/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Guanina/metabolismo
11.
J Nat Prod ; 86(4): 1053-1060, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37043818

RESUMEN

The highly oxygenated indole alkaloid speradine F (4) with a 6/5/6/5/5/5 hexacyclic skeleton was isolated from a culture of Penicillium palitans, together with its precursors ß-cyclopiazonic acid (ß-CPA, 5) and cyclopiazonic acid (CPA, 1). Gene deletion and heterologous expression led to the identification of the responsible five-gene spe cluster for the speradine skeleton formation. Precursor supply experiments proved that 1 was enzymatically converted, via 2-oxoCPA (2), to speradine A (3), which subsequently undergoes multistep nonenzymatic hydroxylations to 4.


Asunto(s)
Alcaloides Indólicos , Penicillium , Oxidación-Reducción , Penicillium/metabolismo
12.
Appl Microbiol Biotechnol ; 107(15): 4845-4852, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37326682

RESUMEN

The fungal prenyltransferase ShPT from Stereum hirsutum was believed to prenylate 4-hydroxybenzyl alcohol and thereby be involved in the vibralactone biosynthesis. In this study, we demonstrate that hydroxynaphthalenes instead of benzyl alcohol or aldehyde were accepted by ShPT for regular C-prenylation in the presence of both dimethylallyl and geranyl diphosphate. Although the natural substrate of ShPT remains unknown, our results provide one additional prenyltransferase from basidiomycetes, which are less studied, in comparison to those from other sources. Furthermore, this study expands the chemical toolbox for regioselective production of prenylated naphthalene derivatives. KEY POINTS: •Basidiomycetous prenyltransferase •Biochemical characterization •A DMATS prenyltransferase prenylating hydroxynaphthalene derivatives.


Asunto(s)
Dimetilaliltranstransferasa , Dimetilaliltranstransferasa/metabolismo , Naftoles , Prenilación , Especificidad por Sustrato
13.
Appl Microbiol Biotechnol ; 107(22): 6887-6895, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37713115

RESUMEN

Prenyltransferases (PTs) from the dimethylallyl tryptophan synthase (DMATS) superfamily are known as efficient biocatalysts and mainly catalyze regioselective Friedel-Crafts alkylation of tryptophan and tryptophan-containing cyclodipeptides (CDPs). They can also use other unnatural aromatic compounds as substrates and play therefore a pivotal role in increasing structural diversity and biological activities of a broad range of natural and unnatural products. In recent years, several prenylated dimeric CDPs have been identified with wide range of bioactivities. In this study, we demonstrate the production of prenylated dimeric CDPs by chemoenzymatic synthesis with a known promiscuous enzyme EchPT1, which uses cyclo-L-Trp-L-Ala as natural substrate for reverse C2-prenylation. High product yields were achieved with EchPT1 for C3-N1' and C3-C3' linked dimers of cyclo-L-Trp-L-Trp. Isolation and structural elucidation confirmed the product structures to be reversely C19/C19'-mono- and diprenylated cyclo-L-Trp-L-Trp dimers. Our study provides an additional example for increasing structural diversity by prenylation of complex substrates with known biosynthetic enzymes. KEY POINTS: • Chemoenzymatic synthesis of prenylated cyclo-L-Trp-L-Trp dimers • Same prenylation pattern and position for cyclodipeptides and their dimers. • Indole prenyltransferases such as EchPT1 can be widely used as biocatalysts.

14.
Appl Microbiol Biotechnol ; 107(1): 261-271, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36441211

RESUMEN

Ascomycetous fungi are often found in agricultural products and foods as contaminants. They produce hazardous mycotoxins for human and animals. On the other hand, the fungal metabolites including mycotoxins are important drug candidates and the enzymes involved in the biosynthesis of these compounds are valuable biocatalysts for production of designed compounds. One of the enzyme groups are members of the dimethylallyl tryptophan synthase superfamily, which mainly catalyze prenylations of tryptophan and tryptophan-containing cyclodipeptides (CDPs). Decoration of CDPs in the biosynthesis of multiple prenylated metabolites in nature is usually initiated by regiospecific C2-prenylation at the indole ring, followed by second and third ones as well as by other modifications. However, the strict substrate specificity can prohibit the further prenylation of unnatural C2-prenylated compounds. To overcome this, we firstly obtained C4-, C5-, C6-, and C7-prenylated cyclo-L-Trp-L-Pro. These products were then used as substrates for the promiscuous C2-prenyltransferase EchPT1, which normally uses the unprenylated CDPs as substrates. Four unnatural diprenylated cyclo-L-Trp-L-Pro including the unique unexpected N1,C6-diprenylated derivative with significant yields were obtained in this way. Our study provides an excellent example for increasing structural diversity by reprogramming the reaction orders of natural biosynthetic pathways. Furthermore, this is the first report that EchPT1 can also catalyze N1-prenylation at the indole ring. KEY POINTS: • Prenyltransferases as biocatalysts for unnatural substrates. • Chemoenzymatic synthesis of designed molecules. • A cyclodipeptide prenyltransferase as prenylating enzyme of already prenylated products.


Asunto(s)
Dimetilaliltranstransferasa , Micotoxinas , Humanos , Dimetilaliltranstransferasa/genética , Dimetilaliltranstransferasa/metabolismo , Triptófano/metabolismo , Prenilación , Indoles/metabolismo , Especificidad por Sustrato , Micotoxinas/metabolismo
15.
J Sep Sci ; 46(13): e2201057, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37031438

RESUMEN

The ability to extract peptides and proteins from biological samples with excellent reusability, high adsorption capacity, and great selectivity is essential in scientific research and medical applications. Inspired by the advantages of core-shell materials, we fabricated a core-shell material using amino-functionalized silica as the core. Benzene-1,3,5-tricarbaldehyde and 3,5-diaminobenzoic acid were used as model organic ligands to construct a shell coating by alternately reacting the two monomers on the surface of silica microspheres. The resultant material featured an outstanding capability for the adsorption of cationic peptides, most likely owing to its porous structure, a large number of carboxylic functional groups, and low mass-transfer resistance. The maximum saturated adsorption capacity reached 833.3 mg/g and the adsorption process took only 20 min. Under optimized adsorption conditions, the core-shell material was used to selectively adsorb cationic peptides from the tryptic digestive solution of lysozyme and bovine serum albumin, Specifically, the analysis results showed seven cationic peptides in the eluate and twenty anionic peptides in the supernatant, which indicates the efficient trap of most cationic peptides in the digestive solution.


Asunto(s)
Péptidos , Albúmina Sérica Bovina , Adsorción , Albúmina Sérica Bovina/química , Dióxido de Silicio/química , Microesferas
16.
Biomed Chromatogr ; 37(9): e5684, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37194377

RESUMEN

Compound Danshen dripping pills (CDDP), a well-known traditional Chinese medicine, is widely used to prevent and treat cardiovascular diseases. CDDP is usually prescribed in combination with clopidogrel (CLP), but the herb-drug interactions are rarely reported. This study evaluated the effects of CDDP on the pharmacokinetics and pharmacodynamics of coadministered CLP, and ensured the safety and efficacy of their usage. The trial design included a single-dose administration and multidose test for 7 consecutive days. Wistar rats received CLP alone or CLP combined with CDDP. After the final dose, plasma samples were collected at various time points, and the active metabolite H4 of CLP was analyzed by ultrafast liquid chromatography coupled with triple quadrupole tandem mass spectrometry. The main pharmacokinetic parameters of Cmax (maximum [or peak] serum concentration), Tmax (peak plasma time), t1/2 (half-time), AUC0-∞ (area under the concentration-time curve from dosing (time 0) to infinite time), and AUC0-t (area under the concentration-time curve from dosing [time 0] to time t) were calculated using the non-compartment model. In addition, prothrombin time, activated partial thromboplastin time, bleeding time, and adenosine diphosphate-induced platelet aggregation were evaluated for anticoagulation and antiplatelet aggregation activity. In this study, we found that CDDP had no significant effect on the metabolism of CLP in rats. In pharmacodynamic studies, the combination group showed significant synergistic antiplatelet activity compared with the CLP or CDDP groups alone. Based on pharmacokinetic and pharmacodynamic results, CDDP and CLP have synergistic effects on antiplatelet aggregation and anticoagulation.

17.
Altern Ther Health Med ; 29(5): 353-357, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37171948

RESUMEN

Objective: This study investigates the expression pattern of neuroepithelial cell transforming 1 (NET-1) in placental tissues from pregnancies with preeclampsia (PE) and explores its role in mediating proliferative and apoptotic capacities of trophoblasts. Methods: The relative mRNA levels of NET-1 in placental tissues obtained from preeclampsia (PE) pregnancies (n = 60) and healthy pregnancies (n = 60) were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Pearson correlation test was conducted to assess the correlation between NET-1 level and systolic (Sp) and diastolic pressure (Dp) in PE pregnancies. After the knockdown of NET-1 in HTR-8/SVneo cells, changes in proliferation and apoptosis were examined using cell counting kit-8 (CCK-8) and flow cytometry, respectively. Results: NET-1 was highly expressed in placental tissues from PE pregnancies. PE patients with a high level of NET-1 had higher Sp and Dp, and NET-1 level was positively correlated with both Sp and Dp. Knockdown of NET-1 in HTR-8/SVneo cells decreased the proliferative rate but increased the apoptotic rate. Conclusions: NET-1 stimulates the development of PE by triggering trophoblast proliferation and inhibiting apoptosis. Therefore, NET-1 could be a potential therapeutic target for treating PE and other related hypertensive disorders during pregnancy.


Asunto(s)
Placenta , Preeclampsia , Femenino , Humanos , Embarazo , Apoptosis , Proliferación Celular , Placenta/metabolismo , Preeclampsia/genética , Preeclampsia/metabolismo , Trofoblastos/metabolismo
18.
Angew Chem Int Ed Engl ; 62(28): e202304252, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157140

RESUMEN

The transannular disulfide functions as a key structural element imparting diverse biological activities to epidithiodiketopiperazines (ETPs). Although mechanisms were proposed in previous studies, α,ß'-disulfide formation in ETPs is not well-determined owing to the failure to identify the hypothetical intermediate. Herein, we characterize the key ortho-quinone methide (o-QM) intermediate and prove its involvement in the carbon-sulfur migration from an α,α'- to an α,ß'-disulfide by elucidating pretrichodermamide A biosynthesis, which is catalyzed by a FAD-dependent thioredoxin oxygenase TdaE harboring a noncanonical CXXQ motif. Biochemical investigations of recombinant TdaE and mutants demonstrated that the construction of the α,ß'-disulfide was initiated by Gln140 triggering proton abstraction for generation of the essential o-QM intermediate, accompanied by ß'-acetoxy elimination. Subsequent attack on the α,α'-disulfide by Cys137 led to disulfide migration and spirofuran formation. This study expands the biocatalytic toolbox for transannular disulfide formation and sets the stage for the targeted discovery of bioactive ETPs.


Asunto(s)
Disulfuros , Indolquinonas , Indolquinonas/química
19.
Angew Chem Int Ed Engl ; 62(18): e202217212, 2023 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-36867112

RESUMEN

Fungal epidithiodiketopiperazines (ETPs) possess large structural diversity and complexity due to modifications of the cyclodipeptide skeleton. Elucidation of the biosynthetic pathway of pretrichodermamide A (1) in Trichoderma hypoxylon revealed a flexible catalytic machinery of multiple enzymes for generating ETP diversity. Seven tailoring enzymes encoded by the tda cluster are involved in 1 biosynthesis, that is, four P450s TdaB and TdaQ for 1,2-oxazine formation, TdaI for C7'-hydroxylation, and TdaG for C4, C5-epoxidation, two methyltransferases TdaH for C6'- and TdaO for C7'-O-methylation, and a reductase TdaD for furan opening. Gene deletions led to the identification of 25 novel ETPs, including 20 shunt products, indicating the catalytic promiscuity of Tda enzymes. Particularly, TdaG and TdaD accept various substrates and catalyze regiospecific reactions at different stages of 1 biosynthesis. Our study not only uncovers a hidden library of ETP alkaloids, but also helps to understand the hidden chemical diversity of natural products by pathway manipulation.


Asunto(s)
Metiltransferasas , Oxazinas/química , Estructura Molecular , Metiltransferasas/metabolismo , Modelos Moleculares
20.
Anal Chem ; 94(18): 6754-6759, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35481373

RESUMEN

Large amounts of coexisting contamination in complex biofluid samples impede the quantified veracity of biomarkers, which is the key problem for disease confirmation. Herein, amyloid-like transformed bovine serum albumin inlaid with gold nanoparticles was used as a coating (BGC) on a substrate composed of silicon nanowires (SW; BGC-SW) under ambient conditions. After modification with the recognition group, BGC-SW could serve as an outstanding platform for the selective separation and sensitive detection of biomarkers in complicated biosamples. First, the BGC on SW with a large surface area exhibits excellent adhesion resistance. The attached amounts of contaminations in biofluids were decreased by over 78% compared with native bovine serum albumin (BSA) as the blocking agent. This is because the phase-transformed BSA coating provides stronger interactions with the SW than bare BSA, which results in a tighter attachment and more uniform coverage of the BGC. Furthermore, the gold matrix laid inside the antiadhesive coating ensures simple cross-linking with the recognition groups to selectively capture various biomarkers in complex biofluids and create a gentle release method. Circulating tumor cells (CTCs) were chosen as template biomarkers to verify the application of A-BGC-SW (BGC-SW modified with sgc8-aptamer) in various separation processes of untreated biofluids. The results showed that approximately six cells could be captured from a 1 mL fresh blood sample containing only 10 CTCs. The easy fabrication and excellent antiadhesion property endow A-BGC-SW with great potential in the field of biological separation.


Asunto(s)
Incrustaciones Biológicas , Nanopartículas del Metal , Células Neoplásicas Circulantes , Incrustaciones Biológicas/prevención & control , Biomarcadores , Oro , Humanos , Albúmina Sérica Bovina/química
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