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1.
Front Pharmacol ; 14: 1229772, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152693

RESUMO

Background: The Chinese pharmacopeia records Terminalia chebula as effective in treating prolonged diarrhea and dysentery, blood in the stool, and prolapse. Modern pharmacological research proves it has multiple pharmacological benefits, including antioxidant, anti-inflammatory, analgesic, hepatoprotective, neuroprotective, and other properties. Objectives: This study aims to clarify the role of Terminalia chebula's ethyl acetate extract (TCEA) on ulcerative colitis (UC) induced by dextran sodium sulfate (DSS) in mice, as well as explore the potential mechanism of action. Materials and methods: The variation of different extracts of T. chebula was detected using the HPLC technique, and the main components in TCEA were identified. DSS was used to establish a mouse model to mimic the physiological state of UC in humans; the alleviating effect of TCEA and positive control 5-ASA on UC mice were evaluated by gavage treatment. Disease progression was assessed by monitoring the mouse's weight change and disease activity index (DAI). The changes in colon tissue were estimated by measuring colon length, HE, and AB-PAS staining and detecting oxidative stress parameters. The results draw from Western blot and real-time PCR showed the TLR4/MyD88/NF-κB pathway may involve in the anti-inflammatory activity of TCEA. Furthermore, the gut flora sequencing technique was employed to monitor the differentiation of intestinal microbiota of mice induced by DSS and TCEA treatment. Results: TCEA significantly lowered DAI scores and inhibited the weight loss and colonic shortening induced by DSS. The colon histomorphology and oxidative stress levels were enhanced after TCEA treatment compared with DSS induced UC group. TCEA attenuated the inflammatory response by regulating TLR4/MyD88/NF-κB pathway activation. Intestinal flora sequencing showed that DSS and TCEA greatly impacted mice's composition and diversity of intestinal microorganisms. But TCEA increased the abundance of Bacteroidetes and decreased the abundance of Firmicutes and Proteobacteria compared with the DSS group, which contributed a lot to returning the intestinal flora to a balanced state. Conclusion: This study confirms the alleviating effect of TCEA on UC and provides new ideas for developing TCEA into a new drug to treat UC.

2.
Molecules ; 28(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570753

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory disease significantly impacting patients' lives. This study aimed to elucidate the alleviating effect of ethyl acetate extract (TBEA) from Terminalia bellirica fruit on UC and to explore its mechanism. TBEA was the fraction with the best anti-inflammatory activity screened using in vitro anti-inflammatory assays, and HPLC initially characterized its composition. The mice model of ulcerative colitis was established after free drinking of 2.5% dextran sulfate sodium for six days, and the experimental group was treated with 50 mg/kg and 100 mg/kg TBEA for seven days. We found that TBEA significantly alleviated symptoms in UC mice, including a physiologically significant reduction in disease activity index and pathological damage to colonic tissue. TBEA dramatically slowed down oxidative stress and inflammatory process in UC mice, as evidenced by decreasing myeloperoxidase and malondialdehyde activities and increasing glutathione and catalase levels by reducing the concentrations of IL-6, IL-1ß, TNF-α, and NO in UC mice, as well as by regulating key proteins in the IL-6/JAK2/STAT3 pathway. Meanwhile, TBEA maintained intestinal homeostasis by regulating intestinal flora structure. Our study provides new ideas for developing TBEA into a new drug to treat UC.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Terminalia , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Citocinas/metabolismo , Terminalia/metabolismo , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Frutas/metabolismo , Colo/metabolismo , Anti-Inflamatórios/uso terapêutico , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Colite/tratamento farmacológico
3.
PNAS Nexus ; 2(6): pgad167, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37275262

RESUMO

A major cause for childhood blindness worldwide is attributed to nutritional vitamin A deficiency. Surprisingly, the molecular basis of the ensuing retinal degeneration has not been well defined. Abundant expression of the retinoid transporter STRA6 in the retinal pigment epithelium (RPE) and homeostatic blood levels of retinol-binding protein delay vitamin A deprivation of the mouse eyes. Hence, genetic dissection of STRA6 makes mice susceptible to nutritional manipulation of ocular retinoid status. We performed RNA-seq analyses and complemented the data with tests of visual physiology, ocular morphology, and retinoid biochemistry to compare eyes with different vitamin A status. Mild ocular vitamin A deficiency decreased transcripts of photoreceptor transduction pathway-related genes and increased transcripts of oxidative stress pathways. The response was associated with impaired visual sensitivity and an accumulation of fluorescent debris in the retina. Severe vitamin A deficiency did not only impair visual perception but also decreased transcripts of genes encoding cell adhesion and cellular junction proteins. This response altered cell morphology, resulted in significant changes in transport pathways of small molecules, and compromised the barrier function of the RPE. Together, our analyses characterize the molecular events underlying nutritional blindness in a novel mouse model and indicate that breakdown of the outer blood-retinal barrier contributes to retinal degeneration and photoreceptor cell death in severe vitamin A deficiency.

4.
Development ; 150(20)2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37306388

RESUMO

The eIF4E family of translation initiation factors bind 5' methylated caps and act as the limiting step for mRNA translation. The canonical eIF4E1A is required for cell viability, yet other related eIF4E families exist and are utilized in specific contexts or tissues. Here, we describe a family called Eif4e1c, for which we find roles during heart development and regeneration in zebrafish. The Eif4e1c family is present in all aquatic vertebrates but is lost in all terrestrial species. A core group of amino acids shared over 500 million years of evolution forms an interface along the protein surface, suggesting that Eif4e1c functions in a novel pathway. Deletion of eif4e1c in zebrafish caused growth deficits and impaired survival in juveniles. Mutants surviving to adulthood had fewer cardiomyocytes and reduced proliferative responses to cardiac injury. Ribosome profiling of mutant hearts demonstrated changes in translation efficiency of mRNA for genes known to regulate cardiomyocyte proliferation. Although eif4e1c is broadly expressed, its disruption had most notable impact on the heart and at juvenile stages. Our findings reveal context-dependent requirements for translation initiation regulators during heart regeneration.


Assuntos
Traumatismos Cardíacos , Miócitos Cardíacos , Animais , Peixe-Zebra/genética , Fator de Iniciação 4E em Eucariotos/genética , Proliferação de Células/genética
5.
Molecules ; 28(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175119

RESUMO

This research aimed to investigate natamycin's antifungal effect and its mechanism against the chestnut pathogen Neofusicoccum parvum. Natamycin's inhibitory effects on N. parvum were investigated using a drug-containing plate culture method and an in vivo assay in chestnuts and shell buckets. The antifungal mechanism of action of natamycin on N. parvum was investigated by conducting staining experiments of the fungal cell wall and cell membrane. Natamycin had a minimum inhibitory concentration (MIC) of 100 µg/mL and a minimum fungicidal concentration (MFC) of 200 µg/mL against N. parvum. At five times the MFC, natamycin had a strong antifungal effect on chestnuts in vivo, and it effectively reduced morbidity and extended the storage period. The cell membrane was the primary target of natamycin action against N. parvum. Natamycin inhibits ergosterol synthesis, disrupts cell membranes, and causes intracellular protein, nucleic acid, and other macromolecule leakages. Furthermore, natamycin can cause oxidative damage to the fungus, as evidenced by decreased superoxide dismutase and catalase enzyme activity. Natamycin exerts a strong antifungal effect on the pathogenic fungus N. parvum from chestnuts, mainly through the disruption of fungal cell membranes.


Assuntos
Ascomicetos , Natamicina , Natamicina/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana
6.
Cancer Gene Ther ; 30(8): 1156-1166, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37231059

RESUMO

Extracellular vesicles (EVs) play a crucial role in regulating cell behavior by delivering their cargo to target cells. However, the mechanisms underlying EV-cell interactions are not well understood. Previous studies have shown that heparan sulfate (HS) on target cell surfaces can act as receptors for exosomes uptake, but the ligand for HS on EVs has not been identified. In this study, we isolated EVs from glioma cell lines and glioma patients and identified Annexin A2 (AnxA2) on EVs as a key HS-binding ligand and mediator of EV-cell interactions. Our findings suggest that HS plays a dual role in EV-cell interactions, where HS on EVs captures AnxA2, and on target cells, it acts as a receptor for AnxA2. Removal of HS from the EV surface inhibits EV-target cell interaction by releasing AnxA2. Furthermore, we found that AnxA2-mediated binding of EVs to vascular endothelial cells promotes angiogenesis, and that antibody against AnxA2 inhibited the ability of glioma-derived EVs to stimulate angiogenesis by reducing the uptake of EVs. Our study also suggests that the AnxA2-HS interaction may accelerate the glioma-derived EVs-mediated angiogenesis and that combining AnxA2 on glioma cells with HS on endothelial cells may effectively improve the prognosis evaluation of glioma patients.


Assuntos
Anexina A2 , Vesículas Extracelulares , Glioma , Humanos , Células Endoteliais/metabolismo , Anexina A2/metabolismo , Ligantes , Vesículas Extracelulares/metabolismo , Glioma/metabolismo , Heparitina Sulfato/metabolismo
7.
Materials (Basel) ; 15(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36499900

RESUMO

The microstructural evolution of SK85 pearlitic steel cold-rolled up to a 90% rolling reduction was characterized by scanning electron microscopy with electron backscattered diffraction (EBSD) and X-ray diffraction (XRD). SK85 steel exhibits excellent cold rolling performance. The interlamellar spacing of pearlite is refined obviously and a tensile strength of 2318 MPa can be reached for SK85 steel after 90% rolling reduction, an increase of 83% from 1264 MPa before rolling. The EBSD observation indicates that the {001} <110> texture becomes pronounced at a 90% rolling reduction in cold-rolled Sk85 steel. A propagation and multiplication of dislocations occur during rolling as the kernel average misorientation (KAM) angles significantly increase from 0.72° to 2.11°. The XRD analysis reveals that bcc ferrite is transformed into a bct structure at a 90% rolling reduction. The strengthening mechanism was discussed.

8.
Nat Commun ; 13(1): 6614, 2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329064

RESUMO

Heterogeneous Nuclear Ribonucleoprotein K (hnRNPK) is a multifunctional RNA binding protein (RBP) localized in the nucleus and the cytoplasm. Abnormal cytoplasmic enrichment observed in solid tumors often correlates with poor clinical outcome. The mechanism of cytoplasmic redistribution and ensuing functional role of cytoplasmic hnRNPK remain unclear. Here we demonstrate that the SCFFbxo4 E3 ubiquitin ligase restricts the pro-oncogenic activity of hnRNPK via K63 linked polyubiquitylation, thus limiting its ability to bind target mRNA. We identify SCFFbxo4-hnRNPK responsive mRNAs whose products regulate cellular processes including proliferation, migration, and invasion. Loss of SCFFbxo4 leads to enhanced cell invasion, migration, and tumor metastasis. C-Myc was identified as one target of SCFFbxo4-hnRNPK. Fbxo4 loss triggers hnRNPK-dependent increase in c-Myc translation, thereby contributing to tumorigenesis. Increased c-Myc positions SCFFbxo4-hnRNPK dysregulated cancers for potential therapeutic interventions that target c-Myc-dependence. This work demonstrates an essential role for limiting cytoplasmic hnRNPK function in order to maintain translational and cellular homeostasis.


Assuntos
Carcinogênese , Ribonucleoproteínas Nucleares Heterogêneas Grupo K , Humanos , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Carcinogênese/genética , Ubiquitinação , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Oncogenes , RNA Mensageiro/metabolismo
9.
Acta Chim Slov ; 69(3): 694-699, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36196828

RESUMO

Two new oxidovanadium(V) complexes, [VOL1(HQ)] (1) and [VOL2(SAH)] (2), were prepared by the reaction of [VO(acac)2] (where acac = acetylacetonate) with N'-(3-ethoxy-2-hydroxybenzylidene)nicotinohydrazide (H2L1) and 8-hydroxyquinoline (HHQ), and N'-(2-hydroxy-4-methoxybenzylidene)nicotinohydrazide (H2L2) and salicylhydroxamic acid (HSAH), respectively, in methanol. Crystal and molecular structures of the complexes were determined by elemental analysis, infrared spectroscopy and single crystal X-ray diffraction. The V atoms in both complexes are in octahedral coordination. Thermal stability of the complexes was studied. Both complexes can decrease the blood glucose level in alloxan-diabetic mice, but the blood glucose level in the treated normal mice was not altered.


Assuntos
Diabetes Mellitus Experimental , Insulinas , Aloxano , Animais , Glicemia , Diabetes Mellitus Experimental/tratamento farmacológico , Hidrazonas/química , Hidroxiquinolinas , Ligantes , Metanol , Camundongos , Oxiquinolina
10.
Chem Commun (Camb) ; 58(47): 6765-6768, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35612002

RESUMO

A new type of organocatalyzed 1,3-thiosulfonylation has been developed to straightforwardly access highly functionalized vinyl sulfones, which features mild conditions, atom- and step-economy, practicability, conciseness, and environmental friendliness. Moreover, these valuable products can be transformed to vinyl sulfides via a base-promoted isomerization. The versatile route can efficiently and rapidly introduce SCD3 groups with excellent levels of deuterium content (>99% D) by utilizing our newly developed SCD3 reagents. Gram-scale operations and further transformations are smoothly carried out, providing promising applications for drug discovery.


Assuntos
Alcadienos , Sulfetos , Sulfonas
11.
Materials (Basel) ; 15(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35407921

RESUMO

The influence of tempering temperature on the microstructure of 0.5Cr0.4W steels was investigated by scanning electron microscope, and the roles of grain boundary character, dislocation, and Taylor factor in sulfide stress cracking (SSC) resistance were interpreted using the election backscattered diffraction technique. The 0.5Cr0.4W steels tempered at 690 °C, 700 °C, and 715 °C all showed tempered martensites. The specimen tempered at 715 °C exhibited a higher critical stress intensity factor (KISSC) of 34.58 MPa·m0.5, but the yield strength of 800 MPa did not meet the criterion of 125 ksi (862 MPa) grade. When the specimen was tempered at 690 °C, the yield strength reached 960 MPa and the KISSC was only 21.36 MPa·m0.5, displaying poorer SSC resistance. The 0.5Cr0.4W steel tempered at 700 °C showed a good combination of yield strength (887 MPa) and SSC resistance (KISSC: 31.16 MPa·m0.5). When increasing the tempering temperature, the local average misorientation and Taylor factor of the 0.5Cr0.4W steels were decreased. The reduced dislocation density, and greater number of grains amenable to slippage, produced less hydrogen transport and a lower crack sensitivity. The SSC resistance was, thus, increased, owing to the minor damage to hydrogen aggregation. Therefore, 700 °C is a suitable tempering temperature for 0.5Cr0.4W casing steel.

12.
Cerebellum ; 21(3): 358-367, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34264505

RESUMO

Spinocerebellar ataxias (SCAs) are a large group of hereditary neurodegenerative diseases characterized by ataxia and dysarthria. Due to high clinical and genetic heterogeneity, many SCA families are undiagnosed. Herein, using linkage analysis, WES, and RP-PCR, we identified the largest SCA36 pedigree in Asia. This pedigree showed some distinct clinical characteristics. Cognitive impairment and gaze palsy are common and severe in SCA36 patients, especially long-course patients. Although no patients complained of hearing loss, most of them presented with hearing impairment in objective auxiliary examination. Voxel-based morphometry (VBM) demonstrated a reduction of volumes in cerebellum, brainstem, and thalamus (corrected P < 0.05). Reduced volumes in cerebellum were also found in presymptomatic carriers. Resting-state functional MRI (R-fMRI) found reduced ReHo values in left cerebellar posterior lobule (corrected P < 0.05). Diffusion tensor imaging (DTI) demonstrated a reduction of FA values in cerebellum, midbrain, superior and inferior cerebellar peduncle (corrected P < 0.05). MRS found reduced NAA/Cr values in cerebellar vermis and hemisphere (corrected P < 0.05). Our findings could provide new insights into management of SCA36 patients. Detailed auxiliary examination are recommended to assess hearing or peripheral nerve impairment, and we should pay more attention to eye movement and cognitive changes in patients. Furthermore, for the first time, our multimodel neuroimaging evaluation generate a full perspective of brain function and structure in SCA36 patients.


Assuntos
Imagem de Tensor de Difusão , Ataxias Espinocerebelares , Cerebelo , Humanos , Imageamento por Ressonância Magnética , Linhagem , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética
13.
Nat Prod Res ; 36(17): 4371-4378, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34965786

RESUMO

Four flavonoid glycosides containing coumaroyl or feruloyl groups were isolated from the male flowers of Ginkgo biloba L., and compounds 3 and 4 were identified as novel compounds. The inhibitory activities against α-glucosidase were investigated by docking studies, in vitro assays and kinetic studies. The docking results showed that all compounds mainly formed hydrogen-bond and π-π-stacking interactions with α-glucosidase. Compound 4 had the lowest binding energy and maximum number of hydrogen bonds. Subsequently, the in vitro assays showed that compound 4 exhibited the strongest inhibitory potency. Finally, the kinetic studies indicated the inhibitory mode of compounds 1-4 against α-glucosidase were mixed types of competitive and non-competitive. Together, these findings suggested that the isolated flavonoid glycosides in this study, especially compound 4, have potential as α-glucosidase inhibitors.


Assuntos
Flavonoides , Ginkgo biloba , Flavonoides/química , Flores/química , Ginkgo biloba/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeos/química , Cinética , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo
14.
Acta Chim Slov ; 68(4): 1008-1015, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34918755

RESUMO

Three new copper(II) complexes, [Cu(LH)2]Br2 (1), [Cu(LH)2]NCS2 (2), and [Cu(LH)2](NO3)2 (3), where LH is the zwitterionic form of 2-bromo-6-((2-(isopropylamino)ethylimino)methyl)phenol (HL), were synthesized and characterized by elemental analysis, IR and UV-vis spectroscopy. The structures of the complexes were further confirmed by single crystal X-ray structure determination. All compounds are mononuclear copper(II) complexes. The Cu atoms in the complexes are coordinated by two imino N and two phenolate O atoms from two LH ligands, forming square planar coordination. The compounds were assayed for their antimicrobial activities.

15.
Ann Transl Med ; 9(16): 1289, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532426

RESUMO

BACKGROUND: To compare the long-term therapeutic effects of stereotactic aspiration (SA), endoscopic evacuation (EE), and open craniotomy (OC) in the surgical treatment of spontaneous basal ganglia hemorrhage and explore the appropriate clinical indications for each technique. METHODS: Multiple-treatment inverse probability of treatment weighting (IPTW)-adjusted logistic regression analysis was performed to evaluate the therapeutic effects of these techniques. The primary and secondary outcomes were 6-month modified Rankin Scale (mRS) and mortality rates, respectively. RESULTS: A total of 703 patients were ultimately enrolled. For the entire cohort, the 6-month mortality rate was significantly higher (OR 2.396, 95% CI: 1.865-3.080), and the 6-month functional outcome was significantly worse (OR 1.359, 95% CI: 1.091-1.692) for SA than that of EE. The 6-month mortality rate for OC was significantly higher (OR 1.395, 95% CI: 1.059-1.837) than that of EE. Further subgroup analysis was stratified by initial hematoma volume and Glasgow Coma Scale (GCS) score. The mortality rate for SA was significantly higher for patients with hematoma volume of 20-40 mL (OR 6.226, 95% CI: 3.848-10.075), 40-80 mL (OR 2.121, 95% CI: 1.492-3.016), and ≥80 mL (OR 5.544, 95% CI: 3.315-9.269) than in the same subgroups of EE. The functional outcomes for SA were significantly worse than that of EE for hematoma volume subgroups of 40-80 mL (OR 1.424, 95% CI: 1.039-1.951) and ≥80 mL (OR 4.224, 95% CI: 1.655-10.776). The mortality rate for SA was significantly higher than that of EE for the GCS score subgroups of 6-8 (OR 2.082, 95% CI: 1.410-3.076) and 3-5 (OR 2.985, 95% CI: 1.904-4.678). The mortality rate for OC was significantly higher for the GCS score of 3-5 subgroup (OR 1.718, 95% CI: 1.115-2.648), and a tendency for a higher mortality rate of 6-8 subgroup (OR 1.442, 95% CI: 0.965-2.156) than that of EE. CONCLUSIONS: EE can decrease the 6-month mortality rate and improve the 6-month functional outcomes of spontaneous basal ganglia hemorrhage in patients with a hematoma volume ≥40 mL. EE can decrease the 6-month mortality rate of spontaneous basal ganglia hemorrhage in patients with a GCS score of 3-8.

17.
Sci Rep ; 11(1): 5754, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707654

RESUMO

We have investigated the crystal structures and mechanical properties of osmium diboride (OsB2) based on the density functional theory. The structures of OsB2 from 0 to 400 GPa were predicted using the particle swarm optimization algorithm structure prediction technique. The orthorhombic Pmmn structure of OsB2 (oP6-OsB2) was found to be the most stable phase under zero pressure and it will transfer to the hexagonal P63/mmc structure (hP6-OsB2) around 12.4 GPa. Meanwhile, we have discovered a new stable orthorhombic Immm structure (oI12-OsB2) above 379.6 GPa. After that, a thorough and comprehensive investigation on mechanical properties of different OsB2 phases is performed in this work. Further studies showed that the hardness of oP6-OsB2 and hP6-OsB2 at zero pressure is 15.6 and 20.1 GPa, while that for oI12-OsB2 under 400 GPa is 15.4 GPa, indicating that these three phases should be potentially hard materials rather than superhard materials. Finally, the pressure-temperature phase diagram of OsB2 is constructed for the first time by using the quasi-harmonic approximation method. Our results showed that the transition pressures of oP6-OsB2 → hP6-OsB2 and hP6-OsB2 → oI12-OsB2 all decreases appreciably with the increase of temperature.

19.
J Sci Food Agric ; 101(10): 4321-4331, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33417244

RESUMO

BACKGROUND: The levels and ratios of sugar and acid are important contributors to fruit taste. Kumquat is one of the most economically important citrus crops, but information on the soluble sugar and organic acid metabolism in kumquat is limited. Here, two kumquat varieties - 'Rongan' (RA) and its mutant 'Huapi' (HP) - were used to assess soluble sugar and organic acid accumulation and the related genes. RESULTS: Soluble sugars include sucrose, glucose and fructose, while malate, quinic acid and citrate are the dominant organic acids in the fruits of both kumquat varieties. HP accumulated more sugars but fewer organic acids than did RA. Transcriptome analysis revealed 63 and 40 differentially expressed genes involved in soluble sugar and organic acid accumulation, respectively. The genes associated with sugar synthesis and transport, including SUS, SPS, TST, STP and ERD6L, were up-regulated, whereas INVs, FRK and HXK genes related to sugar degradation were down-regulated in HP kumquat. For organic acids, the up-regulation of PEPC and NAD-MDH could accelerate malate accumulation. In contrast, high expression of NAD-IDH and GS resulted in citric acid degradation during HP fruit development. Additionally, the PK, PDH, PEPCK and FBPase genes responsible for the interconversion of soluble sugars and organic acids were also significantly altered in the early development stages in HP. CONCLUSION: The high sugar accumulation in HP fruit was associated with up-regulation of SUS, SPS, TST, STP and ERD6L genes. The PEPCK, PEPC, NAD-MDH, NADP-IDH, GS and FBPase genes played important roles in acid synthesis and degradation in HP kumquat. These findings provide further insight into understanding the mechanisms underlying metabolism of sugars and organic acids in citrus. © 2021 Society of Chemical Industry.


Assuntos
Ácidos/metabolismo , Frutas/metabolismo , Proteínas de Plantas/genética , Rutaceae/genética , Açúcares/metabolismo , Ácidos/análise , Ácido Cítrico/metabolismo , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Malatos/metabolismo , Proteínas de Plantas/metabolismo , Rutaceae/metabolismo
20.
Nat Commun ; 12(1): 525, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483505

RESUMO

CTLA-4 is an important regulator of T-cell function. Here, we report that expression of this immune-regulator in mouse B-1a cells has a critical function in maintaining self-tolerance by regulating these early-developing B cells that express a repertoire enriched for auto-reactivity. Selective deletion of CTLA-4 from B cells results in mice that spontaneously develop autoantibodies, T follicular helper (Tfh) cells and germinal centers (GCs) in the spleen, and autoimmune pathology later in life. This impaired immune homeostasis results from B-1a cell dysfunction upon loss of CTLA-4. Therefore, CTLA-4-deficient B-1a cells up-regulate epigenetic and transcriptional activation programs and show increased self-replenishment. These activated cells further internalize surface IgM, differentiate into antigen-presenting cells and, when reconstituted in normal IgH-allotype congenic recipient mice, induce GCs and Tfh cells expressing a highly selected repertoire. These findings show that CTLA-4 regulation of B-1a cells is a crucial immune-regulatory mechanism.


Assuntos
Subpopulações de Linfócitos B/imunologia , Antígeno CTLA-4/imunologia , Homeostase/imunologia , Sistema Imunitário/imunologia , Tolerância Imunológica/imunologia , Animais , Subpopulações de Linfócitos B/metabolismo , Antígeno CTLA-4/genética , Antígeno CTLA-4/metabolismo , Diferenciação Celular/imunologia , Centro Germinativo/citologia , Centro Germinativo/imunologia , Centro Germinativo/metabolismo , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo
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