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1.
J Hazard Mater ; 475: 134925, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-38889458

RÉSUMÉ

The polychaete Perinereis aibuhitensis is used for bioremediation; however, its ability to remove fluorene, a common environmental pollutant, from sediments remains unclear, especially at low concentrations of fluorene (10 mg/kg). In this study, we explored the mechanism of intestinal injury induced by low concentrations of fluorene and the reason intestinal injury is alleviated in high fluorene concentration groups (100 and 1000 mg/kg) using histology, ecological biomarkers, gut microbiome, and metabolic response analyses. The results show that P. aibuhitensis showed high tolerance to fluorene in sediments, with clearance rates ranging 25-50 %. However, the remediation effect at low fluorene concentrations (10 mg/kg) was poor. This is attributed to promoting the growth of harmful microorganisms such as Microvirga, which can cause metabolic disorders, intestinal flora imbalances, and the generation of harmful substances such as 2-hydroxyfluorene. These can result in severe intestinal injury in P. aibuhitensis, reducing its fluorene clearance rate. However, high fluorene concentrations (100 and 1000 mg/kg) may promote the growth of beneficial microorganisms such as Faecalibacterium, which can replace the dominant harmful microorganisms and improve metabolism to reverse the intestinal injury caused by low fluorene concentrations, ultimately restoring the fluorene-removal ability of P. aibuhitensis. This study demonstrates an effective method for evaluating the potential ecological risks of fluorene pollution in marine sediments and provides guidance for using P. aibuhitensis for remediation.


Sujet(s)
Fluorènes , Microbiome gastro-intestinal , Intestins , Métabolomique , Polychaeta , Polluants chimiques de l'eau , Animaux , Fluorènes/toxicité , Fluorènes/métabolisme , Polychaeta/effets des médicaments et des substances chimiques , Polychaeta/métabolisme , Polychaeta/microbiologie , Polluants chimiques de l'eau/toxicité , Polluants chimiques de l'eau/métabolisme , Intestins/microbiologie , Intestins/effets des médicaments et des substances chimiques , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Sédiments géologiques/microbiologie , Sédiments géologiques/composition chimique , Dépollution biologique de l'environnement
2.
Aging (Albany NY) ; 15(20): 11639-11653, 2023 10 26.
Article de Anglais | MEDLINE | ID: mdl-37889534

RÉSUMÉ

Alisol A, a triterpene isolated from Alisma Orientale, has been shown to exhibit anti-inflammatory effects and vascular protection. This study was designed to observe the effect of alisol A on cerebral ischemia (CI)-induced neurovascular dysfunction in the hippocampus and to further explore the potential mechanisms. The results showed that alisol A treatment improved the neurological deficits and cognitive impairment of CI mice. Alisol A reduced gliosis and improved neuronal/glial metabolism. Accordingly, alisol A inhibited inflammatory factors IL-6 and IL-1ß induced by overactivation of astrocytes and microglia, thus protecting the neurovasculature. Furthermore, alisol A promoted the survival of neurons by decreasing the ratio of Bax/Bcl-2, and protected brain microvascular endothelial cells (BMECs) by upregulating the expression of ZO-1, Occludin and CD31. The phosphorylation of protein kinase B (AKT) and glycogen synthase kinase 3ß (GSK3ß) increased after treatment with alisol A. To explore the underlying mechanism, AKT was inhibited. As expected, the neurovascular protection of alisol A above was eliminated by AKT inhibition. The present study primarily suggested that alisol A could exert neurovascular protection in the hippocampus of CI mice by activating the AKT/GSK3ß pathway and may potentially be used for the treatment of CI.


Sujet(s)
Encéphalopathie ischémique , Protéines proto-oncogènes c-akt , Souris , Animaux , Protéines proto-oncogènes c-akt/métabolisme , Glycogen synthase kinase 3 beta , Cellules endothéliales/métabolisme , Encéphalopathie ischémique/traitement médicamenteux , Infarctus cérébral
3.
Front Cell Infect Microbiol ; 13: 1157944, 2023.
Article de Anglais | MEDLINE | ID: mdl-37565064

RÉSUMÉ

Background: In patients with invasive fungal infection (IFI), the steady-state serum trough concentration (C min) of voriconazole (VCZ) is highly variable and can lead to treatment failure (C min < 0.5 mg/L) and toxicity (C min ≥ 5.0 mg/L). However, It remains challenging to determine the ideal maintenance dose to achieve the desired C min level quickly. Aims: This randomized, prospective observational single-center study aimed to identify factors affecting VCZ-C min and maintenance dose and create an algorithmic model to predict the necessary maintenance dose. MeThe study enrolled 306 adult IFI patients, split into two groups: non-gene-directed (A) (where CYP2C19 phenotype is not involved in determining VCZ dose) and gene-directed (B) (where CYP2C19 phenotype is involved in determining VCZ dose). Results: Results indicated that CYP2C19 genetic polymorphisms might significantly impact VCZ loading and maintenance dose selection. CYP2C19 phenotype, C-reaction protein (CRP), and average daily dose/body weight were significant influencers on VCZ-C min, while CYP2C19 phenotype, CRP, and body weight significantly impacted VCZ maintenance dose. A feasible predictive formula for VCZ stable maintenance dose was derived from the regression equation as a maintenance dose (mg) =282.774-0.735×age (year)+2.946×body weight(Kg)-19.402×CYP2C19 phenotype (UM/RM/NM:0, IM:1, PM:2)-0.316×CRP (mg/L) (p < 0.001). Discussion: DiThis formula may serve as a valuable supplement to the Clinical Pharmacogenetics Implementation Consortium (CPIC®) guideline for CYP2C19 and VCZ therapy, especially for IFI patients with highly variable inflammatory cytokines during VCZ therapy.


Sujet(s)
Antifongiques , Infections fongiques invasives , Humains , Voriconazole , Antifongiques/usage thérapeutique , Études prospectives , Cytochrome P-450 CYP2C19/génétique , Cytochrome P-450 CYP2C19/usage thérapeutique , Infections fongiques invasives/traitement médicamenteux , Protéine C-réactive
4.
J Ethnopharmacol ; 313: 116597, 2023 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-37146842

RÉSUMÉ

ETHNOPHARMACOLOGICAL RELEVANCE: The combination of Alisma and Atractylodes (AA), a classical traditional Chinese herbal decoction, may protect against cerebral ischaemia/reperfusion injury (CIRI). However, the underlying mechanism has not been characterized. Intriguingly, exosomal microRNAs (miRNAs) have been recognized as vital factors in the pharmacology of Chinese herbal decoctions. AIM OF THE STUDY: The aim of the present study was to assess whether the neuroprotective effect of AA was dependent on the efficient transfer of miRNAs via exosomes in the brain. MATERIALS AND METHODS: Bilateral common carotid artery ligation (BCAL) was used to induce transient global cerebral ischaemia/reperfusion (GCI/R) in C57BL/6 mice treated with/without AA. Neurological deficits were assessed with the modified neurological severity score (mNSS) and Morris water maze (MWM) test. Western blot (WB) analysis was used to detect the expression of sirtuin 1 (SIRT1) in the cerebral cortex. The inflammatory state was quantitatively evaluated by measuring the expression of phospho-Nuclear factor kappa B (p-NF-κB), Interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) using WB analysis and glial fibrillary acidic protein (GFAP) immunohistochemical staining. The protein expression of zonula occluden-1 (ZO-1), occludin, caudin-5 and CD31 was examined by immunohistochemical staining to determine blood‒brain barrier (BBB) permeability. Exosomes were extracted from the brain interstitial space by ultracentrifugation and identified by transmission electron microscopy (TEM), WB analysis and nanoparticle tracking analysis (NTA). The origin of exosomes was clarified by measuring the specific mRNAs within exosomes via Real Time Quantitative PCR (RT‒qPCR). Differential miRNAs in exosomes were identified using microarray screening and were validated by RT‒qPCR. Exosomes were labelled with fluorescent dye (PKH26) and incubated with bEnd.3 cells, the supernatant was collected, IL-1ß/TNF-α expression was measured using enzyme-linked immunosorbent assay (ELISA), total RNA was extracted, and miR-200a-3p/141-3p expression was examined by RT‒qPCR. In addition, the levels of miR-200a-3p/141-3p in oxygen glucose deprivation/reoxygenation (OGD/R)-induced bEnd.3 cells were quantified. The direct interaction between miR-200a-3p/141-3p and the SIRT1 3' untranslated region (3'UTR) was measured by determining SIRT1 expression in bEnd.3 cells transfected with the miR-200a-3p/141-3p mimic/inhibitor. RESULTS: Severe neurological deficits and memory loss caused by GCI/R in mice was markedly ameliorated by AA treatment, particularly in the AA medium-dose group. Moreover, AA-treated GCI/R-induced mice showed significant increases in SIRT1, ZO-1, occludin, caudin-5, and CD31 expression levels and decreases in p-NF-κB, IL-1ß, TNF-α, and GFAP expression levels compared with those in untreated GCI/R-induced mice. Furthermore, we found that miR-200a-3p/141-3p was enriched in astrocyte-derived exosomes from GCI/R-induced mice and could be inhibited by treatment with a medium dose of AA. The exosomes mediated the transfer of miR-200a-3p/141-3p into bEnd.3 cells, promoted IL-1ß and TNF-α release and downregulated the expression of SIRT1. No significant changes in the levels of miR-200a-3p/141-3p were observed in OGD/R-induced bEnd.3 cells. The miR-200a-3p/141-3p mimic/inhibitor decreased/increased SIRT1 expression in bEnd.3 cells, respectively. CONCLUSION: Our findings demonstrated that AA attenuated inflammation-mediated CIRI by inhibiting astrocyte-derived exosomal miR-200a-3p/141-3p by targeting the SIRT1 gene, which provided further evidence and identified a novel regulatory mechanism for the neuroprotective effects of AA.


Sujet(s)
Alisma , Atractylodes , Encéphalopathie ischémique , microARN , Lésion d'ischémie-reperfusion , Souris , Animaux , Sirtuine-1/génétique , Alisma/génétique , Alisma/métabolisme , Facteur de transcription NF-kappa B , Facteur de nécrose tumorale alpha/pharmacologie , Cellules endothéliales/métabolisme , Astrocytes/métabolisme , Occludine , Souris de lignée C57BL , microARN/métabolisme , Encéphalopathie ischémique/métabolisme , Lésion d'ischémie-reperfusion/métabolisme , Apoptose
5.
Poult Sci ; 102(3): 102403, 2023 Mar.
Article de Anglais | MEDLINE | ID: mdl-36584419

RÉSUMÉ

Glucose transporter protein 4 (GLUT4) plays an important role in regulating insulin-mediated glucose homeostasis in mammals. Until now, studies on GLUT4 have focused on mammals mostly, while chicken GLUT4 has been rarely investigated. In this study, chicken GLUT4 mRNA sequences were obtained by combining conventional amplification, 5'- and 3'- rapid amplification of cDNA ends technique (RACE), then bioinformatics analysis on its genomic structure, splicing pattern, subcellular localization prediction and homologous comparisons were carried out. In addition, the distribution of GLUT4 was detected by RT-qPCR in bird's liver and striated muscles (cardiac muscle, pectoralis and leg muscle) at different ages, including embryonic day 14 (E14), E19, 7-day-old (D7), D21 and D49 (n = 3-4). Results showed that chicken GLUT4 gene produced at least 14 transcripts (GenBank accession No: OP491293-OP491306) through alternative splicing and polyadenylation, which predicted encoding 12 types of amino acid (AA) sequences (with length ranged from 65 AA to 519 AA). These proteins contain typical major facilitator superfamily domain of glucose transporters with length variations, sharing a common sequence of 59 AA, and were predicted to have distinct subcellular localization. The dominant transcript (named as T1) consists of 11 exons with an open reading frame being predicted encoding 519 AA. In addition, analyzing on the spatio-temporal expression of chicken GLUT4 showed it dominantly expressed in pectoralis, leg muscles and cardiac muscle, and the mRNA level of chicken GLUT4 dramatically fluctuated with birds' development in cardiac muscle, pectoralis and leg muscles, with the level at D21 significantly higher than that at E14, E19, and D49 (P < 0.05). These data indicated that chicken GLUT4 undergoes complex alternative splicing events, and GLUT4 expression level in striated muscle was subjected to dynamic regulation with birds' development. Results indicate these isoforms may play overlapping and distinct roles in chicken.


Sujet(s)
Épissage alternatif , Poulets , Animaux , Poulets/génétique , Poulets/métabolisme , Muscles squelettiques/métabolisme , ARN messager/génétique , ARN messager/métabolisme , Glucose/métabolisme , Mammifères/génétique
6.
Front Chem ; 10: 911543, 2022.
Article de Anglais | MEDLINE | ID: mdl-35815214

RÉSUMÉ

One novel diterpenoid lactone named caesalpinbondin A (1) that possesses an unprecedented tetracyclic ring system in which a 6/6/5-fused tricyclic ring and a 4,5-dimethyldihydrofuran-2(3H)-one were connected by a C-C single bond comprising a 5-(naphtho [2,3-b]furan-7-yl)dihydrofuran-2(3H)-one moiety was isolated from the seeds of Caesalpinia bonduc. Its chemical structure was established by extensive spectroscopic methods, and its absolute configuration was further determined by single-crystal X-ray diffraction analysis and electronic circular dichroism calculation. The biological evaluation suggested that compound 1 demonstrated potent anti-Alzheimer's disease (AD) bioactivity, which could delay paralysis of transgenic AD Caenorhabditis elegans. A possible biogenetic pathway of 1 was also proposed.

7.
Genes (Basel) ; 13(7)2022 06 25.
Article de Anglais | MEDLINE | ID: mdl-35885929

RÉSUMÉ

Bitter gourd (Momordica charantia L.) is an economically important vegetable and medicinal crop in many Asian countries. Limited work has been conducted in understanding the genetic basis of horticulturally important traits in bitter gourd. Bitter gourd is consumed primarily for its young, immature fruit, and fruit appearance plays an important role in market acceptability. One such trait is the ridges on the fruit skin. In the present study, molecular mapping of a locus underlying fruit ridge continuity was conducted. Genetic analysis in segregating populations, derived from the crosses between two inbred lines Y1 with continuous ridges (CR) and Z-1-4 with discontinuous ridges (DCR), suggested that CR was controlled by a single recessive gene (cr). High-throughput genome sequencing of CR and DCR bulks combined with high-resolution genetic mapping in an F2 population delimited cr into a 108 kb region with 16 predicted genes. Sequence variation analysis and expression profiling supported the epidermal patterning factor 2-like (McEPFL2) gene as the best candidate of the cr locus. A 1 bp deletion in the first exon of McEPFL2 in Y1 which would result in a truncated McEPFL2 protein may be the causal polymorphism for the phenotypic difference between Y1 and Z-1-4. The association of this 1 bp deletion with CR was further supported by gDNA sequencing of McEPFL2 among 31 bitter gourd accessions. This work provides a foundation for understanding the genetic and molecular control of fruit epidermal pattering and development, which also facilitates marker-assisted selection in bitter melon breeding.


Sujet(s)
Momordica charantia , Épiderme , Fruit/génétique , Séquençage nucléotidique à haut débit , Momordica charantia/génétique , Amélioration des plantes
8.
J Neuroinflammation ; 19(1): 37, 2022 Feb 07.
Article de Anglais | MEDLINE | ID: mdl-35130910

RÉSUMÉ

BACKGROUND: Neuroinflammation and apoptosis are involved in the pathogenesis of ischaemic stroke. Alisol A 24-acetate (24A) exerts a strong inhibitory effect on inflammation and cell apoptosis. The neuroprotective effect of 24A on global cerebral ischaemia/reperfusion (GCI/R) injury remains unclear. METHODS: GCI/R mice were used to investigate the neuroprotective effect of 24A. Modified neurological deficit scores, Morris water maze and object recognition tests were used to evaluate behaviours. Metabolism in brain regions was detected using magnetic resonance spectroscopy (MRS), and changes in microglia, astrocytes and neurons were detected. Inflammation and apoptosis were measured. RESULTS: The results showed that 24A suppressed neurological deficits scores and improved GCI/R induced cognitive dysfunction. It was also observed that 24A could alleviate neuroinflammation, which manifested as 24A inhibited microglia and astrocytes proliferation, downregulated the expression of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and inducible nitric oxide synthase (iNOS) in the GCI/R mice brain. The apoptosis of neurons reduced, and dendritic spines of hippocampal neurons increased in the presence of 24A. In addition, 24A could up-regulate the expression of phosphorylated phosphoinositide 3-kinases (p-PI3K) and phosphorylated protein kinase B (p-AKT) in GCI/R mice brain, and all the morphological, neurological, and biochemical changes of 24A treatment were abolished by the application of PI3K/AKT pathway inhibitor LY294002. CONCLUSIONS: Taken together, our study indicated that 24A alleviated GCI/R injury by inhibiting neuroinflammation and apoptosis through the regulation of the PI3K/AKT pathway.


Sujet(s)
Encéphalopathie ischémique , Neuroprotecteurs , Lésion d'ischémie-reperfusion , Accident vasculaire cérébral , Animaux , Apoptose , Encéphalopathie ischémique/métabolisme , Cholesténones , Souris , Neuroprotecteurs/pharmacologie , Neuroprotecteurs/usage thérapeutique , Phosphatidylinositol 3-kinases/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Lésion d'ischémie-reperfusion/traitement médicamenteux , Lésion d'ischémie-reperfusion/anatomopathologie , Transduction du signal
9.
Angew Chem Int Ed Engl ; 60(41): 22253-22259, 2021 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-34390105

RÉSUMÉ

Room-temperature afterglow (RTA) materials with long lifetime have shown tremendous application prospects in many fields. However, there is no general design strategy to construct near-infrared (NIR)-excited multicolor RTA materials. Herein, we report a universal approach based on the efficient radiative energy transfer that supports the reabsorption from upconversion materials (UMs) to carbon dots-based RTA materials (CDAMs). Thus, the afterglow emission (blue, cyan, green, and orange) of various CDAMs can be activated by UMs under the NIR continuous-wave laser excitation. The efficient radiative energy transfer ensured the persistent multicolor afterglow up to 7 s, 6 s, 5 s, and 0.5 s by naked eyes, respectively. Given the unusual afterglow properties, we demonstrated preliminary applications in fingerprint recognition and information security. This work provides a new avenue for the activation of NIR-excited afterglow in CDAMs and will greatly expand the applications of RTA materials.

10.
Parasitol Res ; 119(7): 2359-2362, 2020 Jul.
Article de Anglais | MEDLINE | ID: mdl-32500368

RÉSUMÉ

Several Cryptosporidium species that infect reptiles, especially squamates, are well described, but there is limited data about Cryptosporidium species infecting crocodilians. In this study, we assess the occurrence of intestinal parasites using traditional microscopic examination and describe the prevalence and Cryptosporidium species in the captive-bred Chinese alligators (Alligator sinensis) in eastern China using molecular methods. The results of microscopic examination showed that no intestinal parasites were detected among the 491 fecal samples examined from the Chinese alligators. The overall prevalence for Cryptosporidium was 0.41% (2/491) by PCR detection using the SSU rRNA locus. Sequence and phylogenetic analysis of the SSU rRNA, COWP, and actin genes revealed the presence of Cryptosporidium testudinis, which has been isolated primarily from chelonians. This is the first detection of the specific DNA of C. testudinis in the feces of the Chinese alligator. This study expands our knowledge of the Cryptosporidium species involved in crocodiles, and more extensive studies are necessary to confirm the validity of C. testudinis in crocodiles.


Sujet(s)
Alligators et crocodiles/parasitologie , Cryptosporidiose/parasitologie , Cryptosporidium/isolement et purification , Animaux , Chine/épidémiologie , Cryptosporidiose/épidémiologie , Cryptosporidium/classification , Cryptosporidium/génétique , ADN des protozoaires/génétique , ADN ribosomique/génétique , Fèces/parasitologie , Gènes de protozoaire/génétique , Phylogenèse
12.
Org Biomol Chem ; 16(10): 1745-1750, 2018 03 07.
Article de Anglais | MEDLINE | ID: mdl-29460936

RÉSUMÉ

A novel C16 tetranorditerpenoid, norcrassin A (1), and an unusual dimeric labdane-type diterpenoid, bicrotonol A (2), were isolated from the roots of Croton crassifolius. Norcrassin A (1) featured a new carbon skeleton with an unprecedented 5/5/5/6 tetracyclic system. Bicrotonol A (2) possessed an unusual tetrahydroxypyran ring linkage connecting two labdane diterpenoid monomers. The structures of all compounds, including the absolute configuration, were elucidated by the interpretation of their NMR spectroscopic data, high resolution mass spectrometry, and single-crystal X-ray diffraction. A plausible biosynthetic pathway of 1 is proposed. The anti-Alzheimer's Disease (AD) activities of 1 and 2 are also evaluated using the AD pathological model.


Sujet(s)
Maladie d'Alzheimer/traitement médicamenteux , Croton/composition chimique , Diterpènes/composition chimique , Diterpènes/usage thérapeutique , Racines de plante/composition chimique , Animaux , Animal génétiquement modifié , Caenorhabditis elegans/génétique , Cristallographie aux rayons X , Modèles animaux de maladie humaine , Diterpènes/isolement et purification , Humains , Spectroscopie par résonance magnétique , Modèles moléculaires
13.
Org Lett ; 18(12): 2844-7, 2016 06 17.
Article de Anglais | MEDLINE | ID: mdl-27230557

RÉSUMÉ

Euphorikanin A (1), an unprecedented diterpenoid lactone which possesses a novel 5/6/7/3-fused tetracyclic ring skeleton, was isolated from the roots of Euphorbia kansui. The chemical structure and absolute stereochemistry were elucidated on the basis of extensive spectroscopic methods and single-crystal X-ray diffraction analysis. Compound 1 exhibited moderate cytotoxicity against two human tumor cell lines HeLa and NCI-446. A proposed biosynthetic pathway of compound 1 is also described.

14.
J Asian Nat Prod Res ; 17(4): 415-9, 2015.
Article de Anglais | MEDLINE | ID: mdl-25363682

RÉSUMÉ

A new eremophilane norsesquiterpenoid (1), together with a known eremophilane sesquiterpenoid (2), was isolated from the leaves of Ligularia virgaurea. The structure of 1 was elucidated by a combination of spectroscopic analysis (IR, 1D NMR, 2D NMR, and HR-ESI-MS), and its absolute configuration was determined by a single-crystal X-ray diffraction experiment (with copper radiation). The known compound 2 was identified by comparison of its physical and spectral data with those reported in the literature. Compound 1 was assayed for its cytotoxic activities against human cervical carcinoma cell (HeLa) and human small cell lung cancer cell (NCI-446) lines.


Sujet(s)
Antinéoplasiques d'origine végétale/isolement et purification , Asteraceae/composition chimique , Sesquiterpènes/isolement et purification , Antinéoplasiques d'origine végétale/composition chimique , Antinéoplasiques d'origine végétale/pharmacologie , Cristallographie aux rayons X , Tests de criblage d'agents antitumoraux , Cellules HeLa , Humains , Structure moléculaire , Résonance magnétique nucléaire biomoléculaire , Sesquiterpènes/composition chimique , Sesquiterpènes/pharmacologie
15.
Nat Prod Commun ; 10(11): 1917-8, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26749826

RÉSUMÉ

A chemical investigation of Croton crassifolius afforded a novel norclerodane diterpenoid (1) with an unprecedented six-membered oxygen ring between C-1 and C-12, together with three known compounds. The structure of the new compound was elucidated based on spectroscopic (IR, 1D, and 2D NMR) and HR-ESI-MS techniques. This report describes the first example of a natural norclerodane with a 4H-chromene ring system.


Sujet(s)
Croton/composition chimique , Diterpènes/composition chimique , Extraits de plantes/composition chimique , Diterpènes/isolement et purification , Spectroscopie par résonance magnétique , Structure moléculaire , Extraits de plantes/isolement et purification , Racines de plante/composition chimique , Spectrométrie de masse ESI
16.
Article de Anglais | MEDLINE | ID: mdl-24046650

RÉSUMÉ

The title compound, C17H20O5, an eremophilane sesquiternoid, was isolated from the roots of Ligularia lapathifolia. The mol-ecule contains four fused rings of which the six-membered ring A adopts a half-chair conformation, the six-membered ring B adopts a chair conformation, the five-membered ring C is almost planar (r.m.s. deviation = 0.015 Å) and the five-membered ring D adopts an envelope conformation with the quaternary C atom as the flap. The methyl and the eth-oxy groups adopt a syn conformation and the A/B ring junction is cis-fused. No directional inter-molecular inter-actions could be identified in the crystal.

17.
Eur J Immunol ; 41(5): 1221-30, 2011 May.
Article de Anglais | MEDLINE | ID: mdl-21469130

RÉSUMÉ

Chloride intracellular channel (CLIC) 4 has diverse functions in membrane trafficking, apoptosis, angiogenesis and cell differentiation. CLIC4 is abundantly expressed in macrophages, but its role in innate immune functions is unclear. Here, we show that primary murine macrophages express increased amounts of CLIC4 after exposure to bacterial lipopolysaccharide (LPS). Endogenous CLIC4 level was significantly elevated in the brain, heart, lung, kidney, liver and spleen after LPS injection of mice. Stable macrophage lines overexpressing CLIC4 produced more TNF, IL-6, IL-12 and CCL5 than mock transfectants when exposed to LPS. To explore the role of CLIC4 in vivo, we generated CLIC4-null mice. These mice were protected from LPS-induced death, and had reduced serum levels of inflammatory cytokines. Upon infection with Listeria monocytogenes, CLIC4-deficient mice were impaired in their ability to clear infection, and their macrophages responded to Listeria by producing less inflammatory cytokines and chemokines than the WT controls. When challenged with LPS in vitro, deletion of clic4 gene had little effect on MAPK and NF-κB activation, but led to a reduced accumulation of phosphorylated interferon response factor 3 (IRF3) within macrophages. Conversely, overexpression of CLIC4 enhanced LPS-mediated IRF3. Thus, these findings suggest that CLIC4 is an LPS-induced product that can serve as a positive regulator of LPS signaling.


Sujet(s)
Canaux chlorure/métabolisme , Immunité innée , Lipopolysaccharides/immunologie , Macrophages/immunologie , Protéines mitochondriales/métabolisme , Animaux , Technique de Western , Lignée cellulaire , Chimiokines/sang , Chimiokines/immunologie , Canaux chlorure/biosynthèse , Canaux chlorure/génétique , Cytokines/sang , Cytokines/immunologie , Cytokines/métabolisme , Test ELISA , Escherichia coli/immunologie , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Génotype , Facteur-3 de régulation d'interféron/métabolisme , Lipopolysaccharides/métabolisme , Listeria monocytogenes/immunologie , Listeria monocytogenes/pathogénicité , Infections à Listeria/immunologie , Infections à Listeria/microbiologie , Souris , Souris de lignée C57BL , Souris knockout , Protéines mitochondriales/biosynthèse , Protéines mitochondriales/génétique , Mitogen-Activated Protein Kinases/métabolisme , Facteur de transcription NF-kappa B/métabolisme , Réaction de polymérisation en chaîne , Choc septique/immunologie , Transduction du signal
18.
FASEB J ; 24(12): 4639-47, 2010 Dec.
Article de Anglais | MEDLINE | ID: mdl-20667979

RÉSUMÉ

Progranulin haploinsufficiency causes frontotemporal dementia with tau-negative, ubiquitin-positive neuronal inclusion pathology. In this study, we showed that progranulin-deficient mice displayed increased depression- and disinhibition-like behavior, as well as deficits in social recognition from a relatively young age. These mice did not have any deficit in locomotion or exploration. Eighteen-month-old progranulin-deficient mice demonstrated impaired spatial learning and memory in the Morris water maze. In addition to behavioral deficits, progranulin-deficient mice showed a progressive development of neuropathology from 12 mo of age, including enhanced activation of microglia and astrocytes and ubiquitination and cytoplasmic accumulation of phosphorylated TDP-43. Thus, progranulin deficiency induced FTD-like behavioral and neuropathological deficits. These mice may serve as an important tool for deciphering underlying mechanisms in frontotemporal dementia.


Sujet(s)
Démence frontotemporale/métabolisme , Démence frontotemporale/physiopathologie , Protéines et peptides de signalisation intercellulaire/déficit , Protéines et peptides de signalisation intercellulaire/métabolisme , Animaux , Protéines de liaison à l'ADN/métabolisme , Modèles animaux de maladie humaine , Démence frontotemporale/génétique , Démence frontotemporale/anatomopathologie , Granulines , Immunohistochimie , Protéines et peptides de signalisation intercellulaire/génétique , Apprentissage du labyrinthe/physiologie , Souris , Progranulines
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