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1.
Plant J ; 117(5): 1330-1343, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37996996

RESUMEN

Plants and bacteria have distinct pathways to synthesize the bioactive vitamin B1 thiamin diphosphate (TDP). In plants, thiamin monophosphate (TMP) synthesized in the TDP biosynthetic pathway is first converted to thiamin by a phosphatase, which is then pyrophosphorylated to TDP. In contrast, bacteria use a TMP kinase encoded by ThiL to phosphorylate TMP to TDP directly. The Arabidopsis THIAMIN REQUIRING2 (TH2)-encoded phosphatase is involved in TDP biosynthesis. The chlorotic th2 mutants have high TMP and low thiamin and TDP. Ectopic expression of Escherichia coli ThiL and ThiL-GFP rescued the th2-3 mutant, suggesting that the bacterial TMP kinase could directly convert TMP into TDP in Arabidopsis. These results provide direct evidence that the chlorotic phenotype of th2-3 is caused by TDP rather than thiamin deficiency. Transgenic Arabidopsis harboring engineered ThiL-GFP targeting to the cytosol, chloroplast, mitochondrion, or nucleus accumulated higher TDP than the wild type (WT). Ectopic expression of E. coli ThiL driven by the UBIQUITIN (UBI) promoter or an endosperm-specific GLUTELIN1 (GT1) promoter also enhanced TDP biosynthesis in rice. The pUBI:ThiL transgenic rice accumulated more TDP and total vitamin B1 in the leaves, and the pGT1:ThiL transgenic lines had higher TDP and total vitamin B1 in the seeds than the WT. Total vitamin B1 only increased by approximately 25-30% in the polished and unpolished seeds of the pGT1:ThiL transgenic rice compared to the WT. Nevertheless, these results suggest that genetic engineering of a bacterial vitamin B1 biosynthetic gene downstream of TMP can enhance vitamin B1 production in rice.


Asunto(s)
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica Ectópica , Tiamina/metabolismo , Tiamina Pirofosfato/genética , Tiamina Pirofosfato/metabolismo , Tiamina Monofosfato/metabolismo , Monoéster Fosfórico Hidrolasas/metabolismo , Bacterias/metabolismo , Proteínas de Unión al ADN/genética
2.
Arch Microbiol ; 206(5): 213, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38616201

RESUMEN

Mulberry bacterial wilt disease, caused by Ralstonia pseudosolanacearum, is a devastating soil-borne disease in the silk-mulberry-related industry. In this study, through high-throughput sequencing, we compared the rhizosphere bacterial composition of the mulberry-resistant cultivar (K10) and susceptible cultivar (G12), confirming Bacillus as a genus-level biomarker for K10. Next, twelve Bacillus spp. isolates, derived from the rhizosphere of K10, were screened for their antagonistic activity against R. pseudosolanacearum. The isolate showing strong antagonism was identified as B. velezensis K0T24 and selected for further analysis. The fermentation supernatant of B. velezensis K0T24 significantly inhibited the growth of R. pseudosolanacearum (82.47%) and the expression of its pathogenic genes. Using B. velezensis K0T24 in mulberry seedlings also increased defense enzyme activities and achieved a control efficacy of up to 55.17% against mulberry bacterial wilt disease. Collectively, our findings demonstrate the potential of B. velezensis K0T24 in suppressing mulberry bacterial wilt disease.


Asunto(s)
Bacillus , Infecciones Bacterianas , Morus , Bacterias , Bacillus/genética
3.
Bioorg Chem ; 150: 107584, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38964146

RESUMEN

Developing multitargeted ligands as promising therapeutics for Alzheimer's disease (AD) has been considered important. Herein, a novel class of cinnamamide/ester-triazole hybrids with multifaceted effects on AD was developed based on the multitarget-directed ligands strategy. Thirty-seven cinnamamide/ester-triazole hybrids were synthesized, with most exhibiting significant inhibitory activity against Aß-induced toxicity at a single concentration in vitro. The most optimal hybrid compound 4j inhibited copper-induced Aß toxicity in AD cells. its action was superior to that of donepezil and memantine. It also moderately inhibited intracellular AChE activity and presented favorable bioavailability and blood-brain barrier penetration with low toxicity in vivo. Of note, it ameliorated cognitive impairment, neuronal degeneration, and Aß deposition in Aß1-42-injured mice. Mechanistically, the compound regulated APP processing by promoting the ADAM10-associated nonamyloidogenic signaling and inhibiting the BACE1-mediated amyloidogenic pathway. Moreover, it suppressed intracellular AChE activity and tau phosphorylation. Therefore, compound 4j may be a promising multitargeted active molecule against AD.

4.
J Am Chem Soc ; 145(36): 20031-20040, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37642381

RESUMEN

Albeit notable endeavors in enantioselective carbene insertion into X-H bonds (X = C, O, N, S, Si, B), the catalytic asymmetric P-H insertion reactions still stand for a long-lasting challenge. By merging transition-metal catalysis with organocatalysis, we achieve a scalable enantioselective P-H insertion transformation between diazo pyrazoleamides and H-phosphine oxides that upon subsequent reduction delivers a wide variety of optically active ß-hydroxyl phosphine oxides in good yields with high enantioselectivity. The achiral copper catalyst fosters the carbenoid insertion into the P-H bond, while the chiral cinchona alkaloid-derived organocatalyst controls the subsequent enantioselective outcome. Density functional theory (DFT) calculations further reveal that the copper catalyst chelates to the organocatalyst, enhances its acidity, and accordingly promotes the enantioselective proton transfer. Our work showcases the potential of combining transition-metal catalysis with organocatalysis to realize elusive asymmetric reactions.

5.
Small ; 19(19): e2207509, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36799141

RESUMEN

2D materials have attracted great interest since the report of graphene. However, because of the fragile stability of ultra-thin nanosheets, most studies are restricted to sheets maintained by strong covalent or coordination bonds. The research on which kind of bonds can maintain the free-standing existence of 2D nanosheets is still of great significance. Recently, 2D ionic salts are successfully synthesized on substrates, but whether 2D ionic salts can free-stand is still a problem. Herein this problem is addressed by a free-standing 2D ionic salt (thickness: ≈2 nm) exfoliated from a 4,4'-bipyridinium hydrochloride salt crystal. The stability of this 2D salt is supported by a strong NH···Cl hydrogen (H)-bonding assisted ionic interaction (17.99 kcal mol-1 ), which is verified by density functional theory calculation and natural bond orbital analysis. The salt crystal has strong air-stable radicals inside and the 2D ionic salt exhibits red fluorescence in solution and in solid-state, especially in solution the stokes shifts are very large (≈ 386 nm). This breakthrough work is not only beneficial for the construction of novel 2D materials but also for the understanding of H-bonding interactions.

6.
Magn Reson Med ; 90(6): 2486-2499, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37582301

RESUMEN

PURPOSE: In resting-state fMRI (rs-fMRI), the global signal average captures widespread fluctuations related to unwanted sources of variance such as motion and respiration, as well as widespread neural activity; however, relative contributions of neural and non-neural sources to the global signal remain poorly understood. This study sought to tackle this problem through the comparison of the BOLD global signal to an adjacent non-brain tissue signal, where neural activity was absent, from the same rs-fMRI scan obtained from anesthetized rats. In this dataset, motion was minimal and ventilation was phase-locked to image acquisition to minimize respiratory fluctuations. Data were acquired using three different anesthetics: isoflurane, dexmedetomidine, and a combination of dexmedetomidine and light isoflurane. METHODS: A power spectral density estimate, a voxel-wise spatial correlation via Pearson's correlation, and a co-activation pattern analysis were performed using the global signal and the non-brain tissue signal. Functional connectivity was calculated using Pearson's linear correlation on default mode network (DMN) regions. RESULTS: We report differences in the spectral composition of the two signals and show spatial selectivity within DMN structures that show an increased correlation to the global signal and decreased intra-network connectivity after global signal regression. All of the observed differences between the global signal and the non-brain tissue signal were maintained across anesthetics. CONCLUSION: These results show that the global signal is distinct from the noise contained in the tissue signal, as support for a neural contribution. This study provides a unique perspective to the contents of the global signal and their origins.


Asunto(s)
Dexmedetomidina , Isoflurano , Ratas , Animales , Isoflurano/farmacología , Imagen por Resonancia Magnética/métodos , Ruido , Mapeo Encefálico/métodos
7.
Mol Ecol ; 32(18): 4999-5012, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37525516

RESUMEN

Genomic structural variations (SVs) are widespread in plant and animal genomes and play important roles in phenotypic novelty and species adaptation. Frequent whole genome duplications followed by (re)diploidizations have resulted in high diversity of genome architecture among extant species. In this study, we identified abundant genomic SVs in the Panax genus that are hypothesized to have occurred through during the repeated polyploidizations/(re)diploidizations. Our genome-wide comparisons demonstrated that although these polyploidization-derived SVs have evolved at distinct evolutionary stages, a large number of SV-intersecting genes showed enrichment in functionally important pathways related to secondary metabolites, photosynthesis and basic cellular activities. In line with these observations, our metabolic analyses of these Panax species revealed high diversity of primary and secondary metabolites both at the tissue and interspecific levels. In particular, genomic SVs identified at ginsenoside biosynthesis genes, including copy number variation and large fragment deletion, appear to have played important roles in the evolution and diversification of ginsenosides. A further herbivore deterrence experiment demonstrated that, as major triterpenoidal saponins found exclusively in Panax, ginsenosides provide protection against insect herbivores. Our study provides new insights on how polyploidization-derived SVs have contributed to phenotypic novelty and plant adaptation.


Asunto(s)
Ginsenósidos , Panax , Saponinas , Ginsenósidos/análisis , Ginsenósidos/química , Ginsenósidos/metabolismo , Panax/genética , Panax/química , Panax/metabolismo , Variaciones en el Número de Copia de ADN , Saponinas/química , Saponinas/genética , Saponinas/metabolismo , Adaptación Fisiológica
8.
Mol Phylogenet Evol ; 182: 107744, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36842731

RESUMEN

Camellia (Theaceae) is a morphologically highly diverse genus of flowering plants and includes many famous species with high economic value, and the phylogeny of this genus is not fully resolved. We used 95 transcriptomes from 87 Camellia species and identified 1481 low-copy genes to conduct a detailed analysis of the phylogeny of this genus according to various data-screening criteria. The results show that, very different from the two existing classification systems of Camellia, 87 species are grouped into 8 main clades and two independent species, and that all 8 clades except Clade 8 were strongly supported by almost all the coalescent or concatenated trees using different gene subsets. However, the relationships among these clades were weakly supported and different from analyses using different gene subsets; furthermore, they do not agree with the phylogeny from chloroplast genomes of Camellia. Additional analyses support reticulate evolution (probably resulting from introgression or hybridization) among some major Camellia lineages, providing explanation for extensive gene tree conflicts. Furthermore, we inferred that together with the formation of East Asian subtropical evergreen broad-leaved forests, Camellia underwent a radiative divergence of major clades at 23 âˆ¼ 19 Ma in the late Miocene then had a subsequent species burst at 10 âˆ¼ 5 Ma. Principal component and cluster analyses provides new insights into morphological changes underlying the evolution of Camellia and a reference to further clarify subgenus and sections of this genus. The comprehensive study here including a nuclear phylogeny and other analyses reveal the rapid evolutionary history of Camellia.


Asunto(s)
Camellia , Theaceae , Filogenia , Camellia/genética , Hibridación Genética
9.
J Sex Med ; 20(9): 1153-1160, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37490314

RESUMEN

BACKGROUND: Hypoandrogenism is a cause of erectile dysfunction (ED). Vascular smooth muscle cell contraction and relaxation are regulated by TRPV1-4 channels. However, the influence of hypoandrogenism on TRPV1-4 and its relationship with erectile function remain unclear. AIM: To reveal whether hypoandrogenism affects erectile function by influencing TRPV1-4 expression in the corpus cavernosum of rats. METHODS: Male Sprague-Dawley rats (N = 36) aged 8 weeks were assigned to 6 groups at random (n = 6): sham operation, castrated, castrated + testosterone replacement, sham operation + transfection, castrated + transfection, and castrated + empty transfection. Four weeks after castration, 20 µL of lentiviral vector (1 × 108 TU/mL) carrying the TRPV4 gene was injected into the penile cavernous tissue of the transfection groups. One week after transfection, the maximum intracavernous pressure (ICPmax)/mean arterial pressure (MAP) and the content of TRPV1-4, phosphorylated eNOS (p-eNOS)/eNOS, and nitric oxide (NO) in penile cavernous tissue of each group were measured. OUTCOMES: Under low androgen conditions, TRPV4 expression in endothelial cells in the rat penile cavernosum was sharply reduced, resulting in a decrease in p-eNOS/eNOS and NO content, which could inhibit erectile function. RESULTS: In rat penile cavernous tissue, TRPV1-4 was expressed in the cell membranes of endothelial cells and smooth muscle cells. The ICPmax/MAP and the content of TRPV4, p-eNOS/eNOS, and NO end product nitrite level in rat penile cavernous tissue was markedly reduced in the castrated group as compared with the sham group (P < .05). The ICPmax/MAP and the content of TRPV4, p-eNOS/eNOS, and NO end product nitrite level in rat penile cavernous tissue were markedly improved in the castrated + transfection group vs the castrated group (P < .01). CLINICAL IMPLICATIONS: Upregulation of TRPV4 expression in penile cavernosum tissue might be a viable therapeutic for ED caused by hypoandrogenism. STRENGTHS AND LIMITATIONS: The specific mechanism of TRPV4 in ED needs to be further verified by androgen receptor or TRPV4 gene knockout experiments. CONCLUSION: Hypoandrogenism may cause ED by reducing the expression of TRPV4 in rat penile cavernous tissue. Upregulation of TRPV4 expression in penile cavernous tissue can increase the ratio of p-eNOS/eNOS and NO levels and ameliorate the erectile function of castrated rats.


Asunto(s)
Disfunción Eréctil , Canales de Potencial de Receptor Transitorio , Humanos , Ratas , Masculino , Animales , Disfunción Eréctil/etiología , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/farmacología , Ratas Sprague-Dawley , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/farmacología , Canales de Potencial de Receptor Transitorio/uso terapéutico , Células Endoteliales/metabolismo , Nitritos/metabolismo , Nitritos/farmacología , Nitritos/uso terapéutico , Erección Peniana/fisiología , Pene , Óxido Nítrico Sintasa de Tipo III/metabolismo
10.
Oral Dis ; 29(7): 2895-2906, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36577658

RESUMEN

OBJECTIVES: Mastication is associated with brain activation at the primary somatosensory cortex (S1) and the primary motor cortex (M1). Masticatory functions differ between patients with cognitive impairment (CI) and cognitively healthy older adults (non-CI). The association between cognitive health, brain network of functional connectivity, and mastication has remained unknown. The study investigated the association between masticatory performance (MP) and the topological feature of the functional network at the M1 and S1 in the CI and non-CI groups. SUBJECTS AND METHODS: Forty-nine non-CI and 15 CI subjects received resting-state (rs) fMRI and assessment of MP. The topological feature of the M1 and S1 was quantified by eigenvector centrality (EC), an index that reflects a brain region as a functional "hub" of brain network. RESULTS: In the non-CI group, MP was significantly correlated with EC of the left M1 and the right M1. The correlation was not statistically significant in the CI group. Cognitive status (CI or non-CI) and EC of the left M1 and the right M1, respectively, were statistically significant predictors to individual MP. CONCLUSION: Cognitive status and the topological feature of the M1 in the intrinsic functional network may contribute to the individual difference in masticatory function.


Asunto(s)
Disfunción Cognitiva , Corteza Motora , Humanos , Anciano , Mapeo Encefálico , Corteza Motora/diagnóstico por imagen , Corteza Motora/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Disfunción Cognitiva/diagnóstico por imagen , Imagen por Resonancia Magnética , Cognición/fisiología
11.
Anal Chem ; 94(18): 6703-6710, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35476420

RESUMEN

Ratiometric assays of label-free dual-signaling reporters with enzyme-free amplification are intriguing yet challenging. Herein, yellow- and red-silver nanocluster (yH-AgNC and rH-AgNC) acting as bicolor ratiometric emitters are guided to site-specifically cluster in two template signaling hairpins (yH and rH), respectively, and originally, both of them are almost non-fluorescent. The predesigned complement tethered in yH is recognizable to a DNA trigger (TOC) related to SARS-CoV-2. With the help of an enhancer strand (G15E) tethering G-rich bases (G15) and a linker strand (LS), a switchable DNA construct is assembled via their complementary hybridizing with yH and rH, in which the harbored yH-AgNC close to G15 is lighted-up. Upon introducing TOC, its affinity ligating with yH is further implemented to unfold rH and induce the DNA construct switching into closed conformation, causing TOC-repeatable recycling amplification through competitive strand displacement. Consequently, the harbored rH-AgNC is also placed adjacent to G15 for turning on its red fluorescence, while the yH-AgNC is retainable. As demonstrated, the intensity ratio dependent on varying TOC is reliable with high sensitivity down to 0.27 pM. By lighting-up dual-cluster emitters using one G15 enhancer, it would be promising to exploit a simpler ratiometric biosensing format for bioassays or clinical theranostics.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , COVID-19/diagnóstico , ADN , Fluorescencia , Humanos , SARS-CoV-2 , Plata , Espectrometría de Fluorescencia
12.
Anal Chem ; 94(22): 8041-8049, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35617342

RESUMEN

It is intriguing to modulate the fluorescence emission of DNA-scaffolded silver nanoclusters (AgNCs) via confined strand displacement and transient concatenate ligation for amplifiable biosensing of a DNA segment related to SARS-CoV-2 (s2DNA). Herein, three stem-loop structural hairpins for signaling, recognizing, and assisting are designed to assemble a variant three-way DNA device (3WDD) with the aid of two linkers, in which orange-emitting AgNC (oAgNC) is stably clustered and populated in the closed loop of a hairpin reporter. The presence of s2DNA initiates the toehold-mediated strand displacement that is confined in this 3WDD for repeatable recycling amplification, outputting numerous hybrid DNA-duplex conformers that are implemented for a transient "head-tail-head" tandem ligation one by one. As a result, the oAgNC-hosted hairpin loops are quickly opened in loose coil motifs, bringing a significant fluorescence decay of multiple clusters dependent on s2DNA. Demonstrations and understanding of the tunable spectral performance of a hairpin loop-wrapped AgNC via switching 3WDD conformation would be highly beneficial to open a new avenue for applicable biosensing, bioanalysis, or clinical diagnostics.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , ADN/química , ADN/genética , Humanos , Nanopartículas del Metal/química , SARS-CoV-2 , Plata/química , Espectrometría de Fluorescencia
13.
Ann Bot ; 130(5): 749-762, 2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-35961674

RESUMEN

BACKGROUND AND AIMS: Elucidating how plant species respond to variable light conditions is important to understand the ecological adaptation to heterogeneous natural habitats. Plant performance and its underlying gene regulatory network have been well documented in sun-grown plants. However, the phenotypic and molecular responses of shade-grown plants under variable light conditions have remained largely unclear. METHODS: We assessed the differences in phenotypic performance between Panax ginseng (shade-grown) and Arabidopsis thaliana (sun-grown) under sunlight, shade and deep-shade conditions. To further address the molecular bases underpinning the phenotypic responses, we compared time-course transcriptomic expression profiling and candidate gene structures between the two species. KEY RESULTS: Our results show that, compared with arabidopsis, ginseng plants not only possess a lower degree of phenotypic plasticity among the three light conditions, but also exhibit higher photosynthetic efficiency under shade and deep-shade conditions. Further comparisons of the gene expression and structure reveal that differential transcriptional regulation together with increased copy number of photosynthesis-related genes (e.g. electron transfer and carbon fixation) may improve the photosynthetic efficiency of ginseng plants under the two shade conditions. In contrast, the inactivation of phytochrome-interacting factors (i.e. absent and no upregulation of the PIF genes) are potentially associated with the observed low degree of phenotypic plasticity of ginseng plants under variable light conditions. CONCLUSIONS: Our study provides new insights into how shade-grown plants respond to variable light conditions. Candidate genes related to shade adaptation in ginseng provide valuable genetic resources for future molecular breeding of high-density planting crops.


Asunto(s)
Arabidopsis , Panax , Panax/genética , Panax/metabolismo , Transcriptoma , Luz , Arabidopsis/genética , Fotosíntesis/genética
14.
Cereb Cortex ; 31(3): 1511-1522, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33108464

RESUMEN

How do intrinsic brain dynamics interact with processing of external sensory stimuli? We sought new insights using functional magnetic resonance imaging to track spatiotemporal activity patterns at the whole brain level in lightly anesthetized mice, during both resting conditions and visual stimulation trials. Our results provide evidence that quasiperiodic patterns (QPPs) are the most prominent component of mouse resting brain dynamics. These QPPs captured the temporal alignment of anticorrelation between the default mode (DMN)- and task-positive (TPN)-like networks, with global brain fluctuations, and activity in neuromodulatory nuclei of the reticular formation. Specifically, the phase of QPPs prior to stimulation could significantly stratify subsequent visual response magnitude, suggesting QPPs relate to brain state fluctuations. This is the first observation in mice that dynamics of the DMN- and TPN-like networks, and particularly their anticorrelation, capture a brain state dynamic that affects sensory processing. Interestingly, QPPs also displayed transient onset response properties during visual stimulation, which covaried with deactivations in the reticular formation. We conclude that QPPs appear to capture a brain state fluctuation that may be orchestrated through neuromodulation. Our findings provide new frontiers to understand the neural processes that shape functional brain states and modulate sensory input processing.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Red en Modo Predeterminado/fisiología , Animales , Imagen por Resonancia Magnética/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Vías Nerviosas/fisiología , Estimulación Luminosa , Descanso/fisiología
15.
Clin Exp Dermatol ; 47(8): 1577-1578, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35340029

RESUMEN

Because sterilization of imaging probes is commonly impossible, the issue of probe contamination and cross-infection becomes an issue when using dermoscopy in the clinic. We describe a simple modification to reduce cross-infection during dermoscopy.


Asunto(s)
Dermoscopía , Neoplasias Cutáneas , Dermoscopía/métodos , Humanos
16.
Clin Exp Dermatol ; 47(6): 1183-1184, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34939212

RESUMEN

We report the use of a marking pen with metallic ink to assist body surface location in reflectance confocal microscopy (RCM). Not only is the marker waterproof, but the metallic ink appears brighter under RCM, thus assisting in identifying location.


Asunto(s)
Tinta , Neoplasias Cutáneas , Humanos , Microscopía Confocal , Piel/diagnóstico por imagen , Piel/patología , Neoplasias Cutáneas/patología
17.
Phytother Res ; 36(12): 4587-4603, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35916377

RESUMEN

Andrographolide(ADE) has been demonstrated to inhibit tumor growth through direct cytotoxicity on tumor cells. However, its potential activity on tumor microenvironment (TME) remains unclear. Tumor-associated macrophages (TAMs), composed mainly of M2 macrophages, are the key cells that create an immunosuppressive TME by secretion of cytokines, thus enhancing tumor progression. Re-polarized subpopulations of macrophages may represent vital new therapeutic alternatives. Our previous studies showed that ADE possessed anti-metastasis and anoikis-sensitization effects. Here, we demonstrated that ADE significantly suppressed M2-like polarization and enhanced M1-like polarization of macrophages. Moreover, ADE inhibited the migration of M2 and tube formation in HUVECs under M2 stimulation. In vivo studies showed that ADE restrained the growth of MDA-MB-231 and HCC1806 human breast tumor xenografts and 4T-1 mammary gland tumors through TAMs. Wnt5a/ß-catenin pathway and MMPs were particularly associated with ADE's regulatory mechanisms to M2 according to RNA-seq and bioinformatics analysis. Moreover, western blot also verified the expressions of these proteins were declined with ADE exposure. Among the cytokines released by M2, PDGF-AA and CCL2 were reduced. Our current findings for the first time elucidated that ADE could modulate macrophage polarization and function through Wnt5a signaling pathway, thereby playing its role in inhibition of triple-negative breast cancer.


Asunto(s)
Neoplasias de la Mama , Diterpenos , Vía de Señalización Wnt , Femenino , Humanos , beta Catenina , Neoplasias de la Mama/tratamiento farmacológico , Microambiente Tumoral , Macrófagos Asociados a Tumores , Diterpenos/farmacología , Células Endoteliales de la Vena Umbilical Humana , Células MDA-MB-231 , Animales
18.
Angew Chem Int Ed Engl ; 61(28): e202204290, 2022 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-35536725

RESUMEN

Catalytic selective hydroxylation of unactivated aliphatic (sp3 ) C-H bonds without a directing group represents a formidable task for synthetic chemists. Through directed evolution of P450BSß hydroxylase, we realize oxyfunctionalization of unactivated C-H bonds in a broad spectrum of aliphatic carboxylic acids with varied chain lengths, functional groups and (hetero-)aromatic moieties in a highly chemo-, regio- and enantioselective fashion (>30 examples, Cß/Cα>20 : 1, >99 % ee). The X-ray structure of the evolved variant, P450BSß -L78I/Q85H/G290I, in complex with palmitic acid well rationalizes the experimentally observed regio- and enantioselectivity, and also reveals a reduced catalytic pocket volume that accounts for the increased reactivity with smaller substrates. This work showcases the potential of employing a biocatalyst to enable a chemical transformation that is particularly challenging by chemical methods.


Asunto(s)
Ácidos Carboxílicos , Sistema Enzimático del Citocromo P-450 , Biocatálisis , Sistema Enzimático del Citocromo P-450/metabolismo , Hidroxilación , Estereoisomerismo
19.
J Cell Mol Med ; 25(2): 686-700, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33225580

RESUMEN

Adoptive immunotherapy is a new potential method of tumour therapy, among which anti-CD19 chimeric antigen receptor T-cell therapy (CAR-T cell), is a typical treatment agent for haematological malignancies. Previous clinical trials showed that the quality and phenotype of CAR-T cells expanded ex vivo would seriously affect the tumour treatment efficacy. Although magnetic beads are currently widely used to expand CAR-T cells, the optimal expansion steps and methods have not been completely established. In this study, the differences between CAR-T cells expanded with anti-CD3/CD28 mAb-coated beads and those expanded with cell-based aAPCs expressing CD19/CD64/CD86/CD137L/mIL-15 counter-receptors were compared. The results showed that the number of CD19-specific CAR-T cells with a 4-1BB and CD28 co-stimulatory domain was much greater with stimulation by aAPCs than that with beads. In addition, the expression of memory marker CD45RO was higher, whereas expression of exhausted molecules was lower in CAR-T cells expanded with aAPCs comparing with the beads. Both CAR-T cells showed significant targeted tumoricidal effects. The CAR-T cells stimulated with aAPCs secreted apoptosis-related cytokines. Moreover, they also possessed marked anti-tumour effect on NAMALWA xenograft mouse model. The present findings provided evidence on the safety and advantage of two expansion methods for CAR-T cells genetically modified by piggyBac transposon system.


Asunto(s)
Antígenos CD19/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Animales , Western Blotting , Antígenos CD8/metabolismo , Línea Celular Tumoral , Electroporación , Citometría de Flujo , Humanos , Inmunoterapia Adoptiva/métodos , Células K562 , Masculino , Ratones , Ratones SCID , Plásmidos/genética , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Neuroimage ; 245: 118630, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34644593

RESUMEN

Functional connectivity, which reflects the spatial and temporal organization of intrinsic activity throughout the brain, is one of the most studied measures in human neuroimaging research. The noninvasive acquisition of resting state functional magnetic resonance imaging (rs-fMRI) allows the characterization of features designated as functional networks, functional connectivity gradients, and time-varying activity patterns that provide insight into the intrinsic functional organization of the brain and potential alterations related to brain dysfunction. Functional connectivity, hence, captures dimensions of the brain's activity that have enormous potential for both clinical and preclinical research. However, the mechanisms underlying functional connectivity have yet to be fully characterized, hindering interpretation of rs-fMRI studies. As in other branches of neuroscience, the identification of the neurophysiological processes that contribute to functional connectivity largely depends on research conducted on laboratory animals, which provide a platform where specific, multi-dimensional investigations that involve invasive measurements can be carried out. These highly controlled experiments facilitate the interpretation of the temporal correlations observed across the brain. Indeed, information obtained from animal experimentation to date is the basis for our current understanding of the underlying basis for functional brain connectivity. This review presents a compendium of some of the most critical advances in the field based on the efforts made by the animal neuroimaging community.


Asunto(s)
Conectoma/métodos , Imagen por Resonancia Magnética , Modelos Animales , Neuroimagen , Animales , Descanso
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