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1.
Plant Physiol ; 195(2): 1053-1068, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38245840

RESUMEN

The hemibiotrophic bacterial pathogen Pseudomonas syringae infects a range of plant species and causes enormous economic losses. Auxin and WRKY transcription factors play crucial roles in plant responses to P. syringae, but their functional relationship in plant immunity remains unclear. Here, we characterized tomato (Solanum lycopersicum) SlWRKY75, which promotes defenses against P. syringae pv. tomato (Pst) DC3000 by regulating plant auxin homeostasis. Overexpressing SlWRKY75 resulted in low free indole-3-acetic acid (IAA) levels, leading to attenuated auxin signaling, decreased expansin transcript levels, upregulated expression of PATHOGENESIS-RELATED GENES (PRs) and NONEXPRESSOR OF PATHOGENESIS-RELATED GENE 1 (NPR1), and enhanced tomato defenses against Pst DC3000. RNA interference-mediated repression of SlWRKY75 increased tomato susceptibility to Pst DC3000. Yeast one-hybrid, electrophoretic mobility shift assays, and luciferase activity assays suggested that SlWRKY75 directly activates the expression of GRETCHEN HAGEN 3.3 (SlGH3.3), which encodes an IAA-amido synthetase. SlGH3.3 enhanced tomato defense against Pst DC3000 by converting free IAA to the aspartic acid (Asp)-conjugated form IAA-Asp. In addition, SlWRKY75 interacted with a tomato valine-glutamine (VQ) motif-containing protein 16 (SlVQ16) in vivo and in vitro. SlVQ16 enhanced SlWRKY75-mediated transcriptional activation of SlGH3.3 and promoted tomato defense responses to Pst DC3000. Our findings illuminate a mechanism in which the SlVQ16-SlWRKY75 complex participates in tomato pathogen defense by positively regulating SlGH3.3-mediated auxin homeostasis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Homeostasis , Ácidos Indolacéticos , Enfermedades de las Plantas , Proteínas de Plantas , Pseudomonas syringae , Solanum lycopersicum , Factores de Transcripción , Solanum lycopersicum/microbiología , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Solanum lycopersicum/inmunología , Ácidos Indolacéticos/metabolismo , Pseudomonas syringae/fisiología , Pseudomonas syringae/patogenicidad , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Inmunidad de la Planta/genética , Plantas Modificadas Genéticamente
2.
Nucleic Acids Res ; 51(21): 11568-11583, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37850650

RESUMEN

The cistrome consists of all cis-acting regulatory elements recognized by transcription factors (TFs). However, only a portion of the cistrome is active for TF binding in a specific tissue. Resolving the active cistrome in plants remains challenging. In this study, we report the assay sequential extraction assisted-active TF identification (sea-ATI), a low-input method that profiles the DNA sequences recognized by TFs in a target tissue. We applied sea-ATI to seven plant tissues to survey their active cistrome and generated 41 motif models, including 15 new models that represent previously unidentified cis-regulatory vocabularies. ATAC-seq and RNA-seq analyses confirmed the functionality of the cis-elements from the new models, in that they are actively bound in vivo, located near the transcription start site, and influence chromatin accessibility and transcription. Furthermore, comparing dimeric WRKY CREs between sea-ATI and DAP-seq libraries revealed that thermodynamics and genetic drifts cooperatively shaped their evolution. Notably, sea-ATI can identify not only positive but also negative regulatory cis-elements, thereby providing unique insights into the functional non-coding genome of plants.


Asunto(s)
Plantas , Factores de Transcripción , Vocabulario , Cromatina , Unión Proteica/genética , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Plantas/genética
3.
Plant J ; 114(6): 1385-1404, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36948885

RESUMEN

Chilling stress seriously impairs photosynthesis and activates a series of molecular responses in plants. Previous studies have shown that ETHYLENE INSENSITIVE 3 (EIN3) and EIN3-like (SlEIL) proteins mediate ethylene signaling and reduce plant tolerance to freezing in tomato (Solanum lycopersicum). However, the specific molecular mechanisms underlying an EIN3/EILs-mediated photoprotection pathway under chilling stress are unclear. Here, we discovered that salicylic acid (SA) participates in photosystem II (PSII) protection via SlEIL2 and SlEIL7. Under chilling stress, the phenylalanine ammonia-lyase gene SlPAL5 plays an important role in the production of SA, which also induces WHIRLY1 (SlWHY1) transcription. The resulting accumulation of SlWHY1 activates SlEIL7 expression under chilling stress. SlEIL7 then binds to and blocks the repression domain of the heat shock factor SlHSFB-2B, releasing its inhibition of HEAT SHOCK PROTEIN 21 (HSP21) expression to maintain PSII stability. In addition, SlWHY1 indirectly represses SlEIL2 expression, allowing the expression of l-GALACTOSE-1-PHOSPHATE PHOSPHATASE3 (SlGPP3). The ensuing higher SlGPP3 abundance promotes the accumulation of ascorbic acid (AsA), which scavenges reactive oxygen species produced upon chilling stress and thus protects PSII. Our study demonstrates that SlEIL2 and SlEIL7 protect PSII under chilling stress via two different SA response mechanisms: one involving the antioxidant AsA and the other involving the photoprotective chaperone protein HSP21.


Asunto(s)
Solanum lycopersicum , Solanum lycopersicum/genética , Complejo de Proteína del Fotosistema II/metabolismo , Ácido Salicílico , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Ascórbico/metabolismo , Etilenos , Frío
4.
J Am Chem Soc ; 146(12): 8425-8434, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38488481

RESUMEN

The precise design of catalytic metal centers with multiple chemical states to facilitate sophisticated reactions involving multimolecular activation is highly desirable but challenging. Herein, we report an ordered macroporous catalyst with heterovalent metal pair (HMP) sites comprising CuII-CuI on the basis of a microporous metal-organic framework (MOF) system. This macroporous HMP catalyst with proximity heterovalent dual copper sites, whose distance is controlled to ∼2.6 Å, on macropore surface exhibits a co-activation behavior of ethanol at CuII and alkyne at CuI, and avoids microporous restriction, thereby promoting additive-free alkyne hydroboration reaction. The desired yield enhances dramatically compared with the pristine MOF and ordered macroporous MOF both with solely isovalent CuII-CuII sites. Density functional theory calculations reveal that the Cu-HMP sites can stabilize the Bpin-CuII-CuI-alkyne intermediate and facilitate C-B bond formation, resulting in a smooth alkyne hydroboration process. This work provides new perspectives to design multimolecular activation catalysts for sophisticated matter transformations.

5.
Anal Chem ; 96(3): 1009-1018, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38181328

RESUMEN

Biothiols including cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) are crucial in maintaining the redox balance in the body, and the metabolism and transportation of biothiols rely on the coreaction of diverse proteins and enzymes. The abnormal concentrations and metabolism of biothiols are closely associated with many diseases. However, due to the same active reaction site of the sulfydryl group in biothiols, it is inevitable to bear a confused signal of mutual influence on both nonselective detection and discriminate detection, which presents a serious challenge of accurately sensing or imaging the three biothiols. By assigning an α,ß-unsaturated ketone moiety as a Michael acceptor to trigger thiols to complete the irreversible equivalent domino response processes of nucleophilic addition, olefinic bond migration, and self-immolation, a targeted strategy was rationally pointed out, and herein, a hemicyanine-based probe CyOCy was prepared as a proof of strategy demonstration. The new probe could be equivalently lit up by Cys, Hcy, GSH, and even biothiol combinations (Cys/Hcy, Cys/GSH, Hcy/GSH, or Cys/Hcy/GSH) with unified linear ranges, detection limits, and response times. The probe CyOCy has been successfully used for the accurate quantification of total biothiols in the serum samples of healthy persons and coronary heart disease patients. In addition, the probe has been applied for cell screening, exogenous biothiol imaging, and monitoring drug-induced biothiol fluctuations. The purposive thinking of this work may provide an effective avenue for the accurate sensing of multicomponent samples.


Asunto(s)
Cisteína , Colorantes Fluorescentes , Humanos , Colorantes Fluorescentes/química , Compuestos de Sulfhidrilo , Carbocianinas , Glutatión , Homocisteína , Espectrometría de Fluorescencia
6.
Small ; : e2400410, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721986

RESUMEN

The construction of defective sites is one of the effective strategies to create high-activity Metal-Organic frameworks (MOFs) catalysts. However, traditional synthesis methods usually suffer from cumbersome synthesis steps and disordered defect structures. Herein, a cluster-cluster co-nucleation (CCCN) strategy is presented that involves the in situ introduction of size-matched functional polyoxometalates (H6P2W18O62, {P2W18}) to intervene the nucleation process of cluster-based MOFs (UiO-66), achieving one-step inducement of exposed defective sites without redundant post-processing. POM-induced UiO-66 ({P2W18}-0.1@UiO-66) exhibits a classical reo topology for well-defined cluster defects. Moreover, the defective sites and the interaction between POM and skeletal cluster nodes are directly observed by Integrated Differential Phase Contrast in Scanning Transmission Electron Microscopy (iDPC-STEM). Owing to the molecular-level proximity between defective sites and POM in the same nano-reaction space, {P2W18}-0.1@UiO-66 exhibits efficient tandem catalysis in the preparation of γ-valerolactone (γ-GVL) from laevulinic acid (LA) by the combination of Lewis and Brønsted acids with 11 times higher performance than defective UiO-66 formed by conventional coordination modulation strategy. The CCCN strategy is applicable to different POM and has the potential to be extended to other cluster-based MOFs, which will pave a new way for the construction of functional MOFs with multi-centered synergistic catalysis.

7.
Reprod Biomed Online ; 49(3): 103914, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38917774

RESUMEN

RESEARCH QUESTION: What impact does dehydroepiandrosterone (DHEA) have on ovarian angiogenesis and function in a rat model of with premature ovarian insufficiency (POI), and what are the potential mechanisms of action? DESIGN: DHEA was added to a culture of human microvascular endothelial cells (HMEC-1) to investigate its effects on cell proliferation, migration and tube formation. A rat model of POI was established by intraperitoneal injection of cyclophosphamide, followed by continuous oral administration of DHEA or vehicle for 28 days. Ovarian angiogenesis, follicular growth and granulosa cell survival in ovarian tissues were assessed through haematoxylin and eosin staining, immunohistochemistry and TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick-end labelling (TUNEL). The effect of DHEA on the fertility of rats with POI was evaluated in pregnant animals. The expression levels of characteristic genes and proteins in the hypoxia-inducible factor (HIF)-1α/vascular endothelial growth factor (VEGF) pathway was determined using quantitative reverse transcription PCR and western blotting. RESULTS: In-vitro experiments revealed that DHEA stimulated the proliferation, migration and tube formation of HMEC-1. In in-vivo studies, DHEA treatment improved the disruption of the oestrous cycle and hormone imbalances in POI rats. Key genes in the HIF-1α/VEGF pathway exhibited up-regulated expression, promoting ovarian angiogenesis in POI rats, and enhancing follicular development and granulosa cell survival, thereby restoring fertility in rats. CONCLUSIONS: DHEA can potentially restore ovarian function in rats with cyclophosphamide-induced POI by up-regulating HIF-1α/VEGF signalling, which promotes the growth of blood vessels in the ovaries.

8.
J Org Chem ; 89(2): 1127-1139, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38166204

RESUMEN

Cycloheptenones are widespread in natural products and bioactive molecules. An efficient and convenient NaH-mediated Cope Rearrangement of doubly activated vinylcyclopropanes is reported for the synthesis of cyclohepten-4-ones. These flexible intramolecular reactions were applicable to a wide range of substrates and could be performed on gram scale. The derivatization of the product leads to short and highly efficient synthesis of some useful functional molecules.

9.
J Dairy Sci ; 107(6): 4092-4107, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38278294

RESUMEN

High-grain (HG) feeding can trigger subacute ruminal acidosis (SARA) and subsequent liver tissue injury. This study investigated pyroptosis and NLRP3 inflammasome activation in SARA-induced liver injury, and the role of mitophagy during this process. Twelve mid-lactating Holstein cows equipped with rumen fistulas were randomly divided into 2 groups: a low-grain (LG) diet group (grain:forage = 4:6) and a HG diet group (grain:forage = 6:4). Each group had 6 cows. The experiment lasted for 3 wk. The ruminal fluid was collected through the rumen fistula on experimental d 20 and 21, and the pH immediately measured. At the end of the experiment, all animals were slaughtered, and peripheral blood and liver tissue were collected. The ruminal pH was lower in the HG group than that in the LG group at all time points. In addition, the ruminal pH in the HG group was lower than 5.6 at 3 consecutive time points after feeding (4, 6, and 8 h on d 20; 2, 4, and 6 h on d 21), indicating that HG feeding induced SARA. The content of lipopolysaccharide, IL-1ß, and apoptosis-related cysteine protease 1 (caspase-1) and the activity of alanine aminotransferase and aspartate aminotransferase in the blood plasma of the HG group were all significantly increased. Hepatic caspase-1 activity was increased in the livers of the HG group. The increased expression levels of pyroptosis- and NLRP3 inflammasome-related genes IL1B, IL18, gasdermin D (GSDMD), apoptosis-associated speck-like protein containing a card (ASC), NLR family pyrin domain-containing 3 (NLRP3), and caspase-1 (CASP1) in liver tissue of the HG group were detected. Furthermore, western blot analysis showed that HG feeding led to increased expression of pyroptosis- and NLRP3 inflammasome-related proteins GSDMD N-terminal (GSDMD-NT), IL-1ß, IL-18, cleaved-caspase-1, ASC, NLRP3, and cleaved-caspase-11 and upregulated expression of mitophagy-related proteins microtubule-associated protein 1 light chain 3 II (MAP1LC3-II), beclin 1 (BECN1), Parkin, and PTEN-induced kinase 1 (PINK1) in liver tissue. Collectively, our results revealed that SARA caused increased mitophagy and activated the NLRP3 inflammasome, causing pyroptosis and subsequent liver injury in dairy cows fed a HG diet.


Asunto(s)
Acidosis , Alimentación Animal , Dieta , Hígado , Mitofagia , Piroptosis , Rumen , Animales , Bovinos , Acidosis/veterinaria , Acidosis/metabolismo , Femenino , Dieta/veterinaria , Rumen/metabolismo , Hígado/metabolismo , Hígado/patología , Inflamasomas/metabolismo , Enfermedades de los Bovinos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Grano Comestible , Lactancia
10.
Small ; 19(23): e2206160, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36890776

RESUMEN

Through inducing death receptor (DR) clustering to activate downstream signaling, tumor necrosis factor related apoptosis inducing ligand (TRAIL) trimers trigger apoptosis of tumor cells. However, the poor agonistic activity of current TRAIL-based therapeutics limits their antitumor efficiency. The nanoscale spatial organization of TRAIL trimers at different interligand distances is still challenging, which is essential for the understanding of interaction pattern between TRAIL and DR. In this study, a flat rectangular DNA origami is employed as display scaffold, and an "engraving-printing" strategy is developed to rapidly decorate three TRAIL monomers onto its surface to form DNA-TRAIL3 trimer (DNA origami with surface decoration of three TRAIL monomers). With the spatial addressability of DNA origami, the interligand distances are precisely controlled from 15 to 60 nm. Through comparing the receptor affinity, agonistic activity and cytotoxicity of these DNA-TRAIL3 trimers, it is found that ≈40 nm is the critical interligand distance of DNA-TRAIL3 trimers to induce death receptor clustering and the resulting apoptosis.Finally, a hypothetical "active unit" model is proposed for the DR5 clustering induced by DNA-TRAIL3 trimers.


Asunto(s)
Neoplasias , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF , Ligandos , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/genética , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Ligando Inductor de Apoptosis Relacionado con TNF/farmacología , Apoptosis , Factor de Necrosis Tumoral alfa , Línea Celular Tumoral
11.
Small ; 19(23): e2300125, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36879481

RESUMEN

The widespread preexisting immunity against virus-like particles (VLPs) seriously limits the applications of VLPs as vaccine vectors. Enabling technology for exogenous antigen display should not only ensure the assembly ability of VLPs and site-specific modification, but also consider the effect of preexisting immunity on the behavior of VLPs in vivo. Here, combining genetic code expansion technique and synthetic biology strategy, a site-specific modification method for hepatitis B core (HBc) VLPs via incorporating azido-phenylalanine into the desired positions is described. Through modification position screening, it is found that HBc VLPs incorporated with azido-phenylalanine at the main immune region can effectively assemble and rapidly conjugate with the dibenzocycolctyne-modified tumor-associated antigens, mucin-1 (MUC1). The site-specific modification of HBc VLPs not only improves the immunogenicity of MUC1 antigens but also shields the immunogenicity of HBc VLPs themselves, thereby activating a strong and persistent anti-MUC1 immune response even in the presence of preexisting anti-HBc immunity, which results in the efficient tumor elimination in a lung metastatic mouse model. Together, these results demonstrate the site-specific modification strategy enabled HBc VLPs behave as a potent antitumor vaccine and this strategy to manipulate immunogenicity of VLPs may be suitable for other VLP-based vaccine vectors.


Asunto(s)
Virus de la Hepatitis B , Vacunas de Partículas Similares a Virus , Animales , Ratones , Virus de la Hepatitis B/genética , Vacunas de Partículas Similares a Virus/genética , Antígenos de Neoplasias , Ratones Endogámicos BALB C
12.
Biol Reprod ; 109(6): 918-937, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-37672216

RESUMEN

Intrauterine adhesions (IUA) are a common gynecological problem. Stem cell therapy has been widely used in the treatment of IUA. However, due to the complex and harsh microenvironment of the uterine cavity, the effectiveness of such therapy is greatly inhibited. This study aimed to investigate whether melatonin pretreatment enhances the efficacy of human umbilical cord mesenchymal stem cells (HucMSCs) in IUA treatment in rats. First, we explored the effect of melatonin on the biological activity of HucMSCs in vitro through a macrophage co-culture system, Cell Counting Kit 8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), flow cytometry, immunofluorescence staining, and qRT-PCR. Subsequently, we established the IUA rat model and tracked the distribution of HucMSCs in this model. In addition, we observed the number of M1 and M2 macrophages through immunofluorescence staining and detected the levels of inflammatory cytokines. Four weeks after cell transplantation, HE, Masson, and immunohistochemical staining were performed. In vitro experiments showed that melatonin pretreatment of HucMSCs promoted proliferation, reduced apoptosis, up-regulated the stemness gene, and regulated macrophage polarization. In vivo, melatonin pretreatment caused more HucMSCs to remain in the uterine cavity. Melatonin-pretreated HucMSCs recruited more macrophages, regulated macrophage polarization, and reduced inflammation. Melatonin-pretreated HucMSCs relieved fibrosis, increased endometrium thickness, and up-regulated CD34, vimentin, proliferating cell nuclear antigen (PCNA), and alpha small muscle antigen (α-SMA) expression. Fertility tests showed that melatonin-pretreated HucMSCs increased the number of embryos. In summary, pretreatment with melatonin was beneficial for HucMSC treatment because it enhanced the cell's ability to recruit macrophages and regulate macrophage polarization, which led to the regeneration of the endometrium and improved pregnancy outcomes.


Asunto(s)
Melatonina , Células Madre Mesenquimatosas , Enfermedades Uterinas , Embarazo , Femenino , Ratas , Humanos , Animales , Melatonina/farmacología , Melatonina/metabolismo , Endometrio/metabolismo , Enfermedades Uterinas/terapia , Enfermedades Uterinas/metabolismo , Fertilidad , Macrófagos , Cordón Umbilical
13.
Biol Reprod ; 109(5): 736-748, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37602667

RESUMEN

BACKGROUND: Invasion of the endometrium by trophoblast cells is a key event during pregnancy, although the underlying mechanism remains unclear. Aquaporin 9 (AQP 9) is expressed in many eukaryotes and is associated with cell invasion. The objective of this study was to evaluate the significance of AQP9 in recurrent spontaneous abortion. METHODS: We screened the GSE22490 dataset and further differentiated aquaporin 9 expression in villi. AQP9 was evaluated as one of the key factors in abortion by injecting AQP9 overexpressed plasmid into the uterus of CD1 mice. Trophoblast cells were transfected with AQP9-overexpressing plasmid or siAQP9 to measure cell proliferation, migration, invasion, and apoptosis. Western blot was used to measure changes in the expression of invasion, epithelial-mesenchymal transformation process, and PI3K/AKT pathway. Finally, the role of AQP9 in PI3K/AKT signaling pathway was determined using the PI3K/AKT inhibitor, LY294002, and activator, 740Y-P. RESULTS: AQP9 is highly expressed in recurrent spontaneous abortion villus. Intrauterine injections of AQP9-overexpressing plasmid into CD1 mice resulted in atrophy and blackness of the gestational sac and increased the absorption rate, it is the causative factor of abortion. AQP9 upregulation inhibited the proliferation, invasion, migration, and epithelial-mesenchymal transformation process in vitro of trophoblast cells and increased cell apoptosis. The opposite result was observed after silencing AQP9. AQP9 overexpression also inhibited the PI3K/AKT pathway. LY294002 and 740Y-P partially recovered AQP9-induced trophoblast invasion and migration via the PI3K/AKT pathway. CONCLUSIONS: AQP9 reduces the invasive ability of trophoblast cells by regulating PI3K/AKT signaling pathway, participating in recurrent spontaneous abortion.


Asunto(s)
Aborto Espontáneo , Acuaporinas , Fragmentos de Péptidos , Receptores del Factor de Crecimiento Derivado de Plaquetas , Humanos , Embarazo , Femenino , Animales , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Trofoblastos/metabolismo , Acuaporinas/genética , Acuaporinas/metabolismo , Proliferación Celular , Transición Epitelial-Mesenquimal , Movimiento Celular
14.
Microb Pathog ; 176: 105996, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36709006

RESUMEN

This study aimed to investigate the effect and mechanism of a high concentrate (HC) diet on the inflammatory response and cellular tight junctions (TJs) in the mammary gland of dairy cows. Twelve lactating Holstein dairy cows were randomly assigned into low concentrate (LC) and HC groups (n = 6), which were fed with LC diet and HC diet respectively for 3 weeks. The HC diet lead to subacute ruminant acidosis with a rumen pH < 5.6 more than 3 h daily. The HC diet triggered an inflammatory response with increased levels of inflammatory cytokines in the lacteal vein, upregulated expression of inflammation-related genes, elevated activity of myeloperoxidase, and inflammatory cells infiltration in the mammary gland. Furthermore, the HC diet induced the activation of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways with enhanced phosphorylation ratios of NF-κB P65, inhibitor of NF-κB (IκB), P38 and extracellular signal-regulated kinase 1/2 (ERK1/2) as well as decreased ratios of DNA methylation and chromatin compaction of genes coding for proinflammatory cytokines, which contributed to the upregulation of proinflammatory cytokine expression. The HC diet also destroyed the integrity of TJ with discontinuous and decreased expression levels of zonula occludens-1, Occludin, Claudin-4 and increased expression level of Claudin-1 in the mammary epithelial cells compared with LC group. Conclusively, the HC diet induced the activation of NF-κB and MAPK signaling pathways and epigenetic modifications, promoted the transcription of proinflammatory cytokines, and finally caused inflammatory response and TJ disruption in the mammary gland of dairy cows.


Asunto(s)
FN-kappa B , Uniones Estrechas , Femenino , Animales , Bovinos , FN-kappa B/metabolismo , Uniones Estrechas/metabolismo , Lactancia , Dieta/veterinaria , Citocinas/metabolismo , Alimentación Animal/análisis
15.
Microb Pathog ; 180: 106135, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37172660

RESUMEN

High-concentrate diet can cause metabolic diseases, such as subacute ruminal acidosis (SARA), and secondary mastitis. To investigate the effect of SARA induced by high-concentrate diet on the lysine lactylation (Kla) and inflammatory responses in the mammary gland of dairy cows and the mechanism between them, we selected twelve mid-lactation Holstein cows with similar body conditions for modelling. They were randomly divided into two groups, fed a low-concentrate diet (LC) and a high-concentrate diet (HC) for 21 days. Our results showed that high-concentrate diet feeding significantly reduced ruminal pH, and the pH was below 5.6 for more than 3 h per day, indicating successful induction of the SARA model. Lactic acid concentrations in mammary gland and plasma were higher in the HC group than that in the LC group. HC diet feeding significantly up-regulated the expression levels of the Pan Kla, H3K18la, p300/CBP and monocarboxylate transporter 1 (MCT1) in the mammary gland. In addition, the mRNA expression levels of inflammatory factors were significantly regulated, including IL-1ß, IL-1α, IL-6, IL-8, SAA3, and TNF-α, while the anti-inflammatory factor IL-10 was down-regulated. The mammary gland of HC group was structurally disorganized with incomplete glandular vesicles, with a large number of detached mammary epithelial cells and inflammatory cells infiltration. The up-regulation of TLR4, TNF-α, p-p65, and p-IκBα indicated that the TLR4/NF-κB signaling pathway was activated. In conclusion, this study found that HC diet feeding can induce SARA and increase the concentration of lactic acid in mammary gland and plasma. Then, lactic acid could be transported into cells by MCT1 and up-regulate the expression level of histone lactylation mediated by p300/CBP, and subsequently promote the activation of TLR4/NF-κB signaling pathway, ultimately causing inflammatory responses in the mammary gland.


Asunto(s)
Enfermedades de los Bovinos , FN-kappa B , Femenino , Animales , Bovinos , FN-kappa B/metabolismo , Regulación hacia Arriba , Histonas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Lactancia , Dieta/veterinaria , Dieta/métodos , Concentración de Iones de Hidrógeno , Leche/metabolismo , Enfermedades de los Bovinos/metabolismo
16.
Exp Eye Res ; 234: 109607, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37517541

RESUMEN

Pseudomonas aeruginosa is a common pathogenic bacteria in canine ophthalmology. Lipopolysaccharide (LPS), a component in the cell wall of gram-negative bacteria, is released following bacterial lysis and causes pathology and inflammation of the cornea. Antibiotics are used to treat bacterial keratitis, and the reuse of antibiotics can easily cause bacterial resistance. Research has shown that glutamine (GLN) has anti-inflammatory and antioxidant biological functions. Herein, we explored the effects and underlying mechanisms of GLN and established an LPS-induced cornea inflammation model. Treatment groups comprised: control check (CK), LPS, LPS + GLN, and Sham groups. Topical GLN treatment alleviated corneal opacity, reduced corneal injury, and accelerated corneal wound healing. Furthermore, GLN treatment altered the uniform distribution of corneal epithelial cells and transformed the healing approach of these cells in the corneal wound from crawling to filling. The expression of Toll-like receptor 4 (TLR4), IL-6, TNF-α, and p-p65 and the activity of myeloperoxidase and superoxide dismutase decreased while the content of malondialdehyde increased in the LPS + GLN group compared with those in the LPS group. Thus, our study suggests that LPS-induced inflammation and oxidative stress may be suppressed via the TLR4/NF-κB signaling pathway by GLN and that GLN could be used as an adjunct therapy to reduce antibiotic use.


Asunto(s)
Queratitis , Lipopolisacáridos , Perros , Animales , Lipopolisacáridos/toxicidad , Receptor Toll-Like 4/metabolismo , Glutamina/farmacología , Glutamina/metabolismo , Queratitis/tratamiento farmacológico , Queratitis/prevención & control , FN-kappa B/metabolismo , Inflamación/patología , Estrés Oxidativo
17.
Reprod Biomed Online ; 46(3): 425-435, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36604215

RESUMEN

RESEARCH QUESTION: What are the levels of progranulin (PGRN) expression in primary endometrial stromal cells (ESC) and endometrial tissue in patients with endometriosis (EMS)? What is the role and mechanism of action of PGRN in EMS? DESIGN: Endometrial tissue was collected from 30 patients, 15 with EMS (EMS group) and 15 without EMS (non-EMS group). PGRN expression in endometrial tissue and ESC was analysed by immunohistochemistry, immunofluorescence, western blotting and quantitative reverse transcription polymerase chain reaction. PGRN overexpression and silencing ESC were established with lentivirus to detect the effect on proliferation, invasion and migration. The relationship between PGRN and the phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) signalling pathway was verified by western blotting. A rescue assay was performed with PI3K inhibitor treatment. RESULTS: The PGRN expression was significantly higher in EMS samples. PGRN up-regulation promoted proliferation (P = 0.007), migration (P = 0.002) and invasion (P < 0.001) of eutopic endometrial stromal cells (EUESC). The ratio of p-AKT/AKT was higher in the overexpression PGRN (ovPGRN) group than in the overexpression-NC (ovNC) group (P = 0.004). Silencing PGRN produced the opposite results, and LY2940002 addition reversed the effect of PGRN up-regulation on the proliferation, invasion and migration of EUESC. CONCLUSIONS: PGRN might promote the proliferation, invasion and migration of EUESC via the PI3K/Akt signalling pathway. These preliminary in-vitro findings may present a new perspective and inspire further study of the mechanism of EMS.


Asunto(s)
Endometriosis , Proteínas Proto-Oncogénicas c-akt , Femenino , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Endometriosis/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Progranulinas/metabolismo , Progranulinas/farmacología , Movimiento Celular , Proliferación Celular , Células del Estroma/metabolismo , Endometrio/metabolismo
18.
J Org Chem ; 88(15): 10670-10681, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37467204

RESUMEN

The construction of multisubstituted ß-pyrrolinones from simple starting materials remains a great challenge. Recently, a novel Cu(I)-catalyzed [2 + 2 + 1] cycloaddition reaction was developed for rapid access to fully substituted ß-pyrrolinones, which are difficult to synthesize through traditional methods as this approach may involve unusual C-nucleophilic addition of enamines and umpolung of imines. Elucidating the reaction mechanism may inspire the development of new methodologies via the unusual C-nucleophilic addition of enamines and imines. However, the reaction mechanism is still unclear because none of the intermediates was observed during the reaction process. In this work, we employed theoretical and computational chemistry to investigate the possible pathway. Finally, the calculated results indicate that ketene formed by the Wolff rearrangement of α-diazo-ß-ketoester reacts with enamine formed by the addition of alkynes and amine, affording the five-membered azaheterocycle, and this process involves the formation of a six-membered ring intermediate and sequential isomerization, and the further dehydrogenation needs to be assisted with solvent MeNO2.

19.
Phys Chem Chem Phys ; 25(10): 7251-7256, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36810899

RESUMEN

The electrochemical methodology is available for the functionalization of fullerenes. However, intricate and ambiguous issues remain to be identified for some electrochemical reactions. In this work, density functional theory (DFT) calculations reveal that the electron delocalization of C60 in fullerobenzofuran (RF5) and the C60-fused lactone (RL6) declines with the electron injection of electrochemistry, and clear active sites can be obtained to react with the electrophilic agent. Furthermore, the selectivity of the addition reaction depends on the Oδ- site, which is inclined to react with the Cδ+ of C60 after electron injection or the Cδ+ of PhCH2+, forming a new C-O bond.

20.
Phys Chem Chem Phys ; 25(33): 22304-22309, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37578133

RESUMEN

Hetero-bimetallic organic compounds have great potential for the development of new nonlinear optical (NLO) materials, due to their large first hyperpolarizabilities (ßtot). Herein, due to their versatility and ease of functionalization, the second-order NLO properties of a series of linked sandwich metallacarboranes were studied by changing their linkages to different organic groups. The calculated ßtot values suggest that the NLO response was significantly enhanced when an alkenyl group of appropriate length was inserted into the B-B or C-C bonds connecting the metallacarborane units. Time-dependent density-functional theory was used to explain how the connection modes and the use of organic groups as linkers can give rise to different types of charge transfer. Moreover, the NLO responses of the redox states (+1 and -1) were calculated, with the aim of investigating the NLO switching effects of the -1/0/+1 states. Comparison of the ßtot values for the different states shows that the studied linked sandwich metallacarboranes could serve as three-state NLO molecular switches stimulated by redox processes.

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