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1.
Plant Physiol Biochem ; 212: 108794, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850730

RESUMO

With the increasing occurrence of global warming, drought is becoming a major constraint for plant growth and crop yield. Plant cell walls experience continuous changes during the growth, development, and in responding to stressful conditions. The plant WRKYs play pivotal roles in regulating the secondary cell wall (SCW) biosynthesis and helping plant defend against abiotic stresses. qRT-PCR evidence showed that OsWRKY12 was affected by drought and ABA treatments. Over-expression of OsWRKY12 decreased the drought tolerance of the rice transgenics at the germination stage and the seedling stage. The transcription levels of drought-stress-associated genes as well as those genes participating in the ABA biosynthesis and signaling were significantly different compared to the wild type (WT). Our results also showed that less lignin and cellulose were deposited in the OsWRKY12-overexpressors, and heterogenous expression of OsWRKY12 in atwrky12 could lower the increased lignin and cellulose contents, as well as the improved PEG-stress tolerance, to a similar level as the WT. qRT-PCR results indicated that the transcription levels of all the genes related to lignin and cellulose biosynthesis were significantly decreased in the rice transgenics than the WT. Further evidence from yeast one-hybrid assay and the dual-luciferase reporter system suggested that OsWRKY12 could bind to promoters of OsABI5 (the critical component of the ABA signaling pathway) and OsSWN3/OsSWN7 (the key positive regulators in the rice SCW thickening), and hence repressing their expression. In conclusion, OsWRKY12 mediates the crosstalk between SCW biosynthesis and plant stress tolerance by binding to the promoters of different downstream genes.


Assuntos
Parede Celular , Secas , Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Estresse Fisiológico , Fatores de Transcrição , Oryza/genética , Oryza/metabolismo , Parede Celular/metabolismo , Parede Celular/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Estresse Fisiológico/genética , Lignina/biossíntese , Lignina/metabolismo , Plantas Geneticamente Modificadas , Celulose/biossíntese , Celulose/metabolismo , Ácido Abscísico/metabolismo
2.
Carbohydr Polym ; 339: 122214, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823900

RESUMO

The polysaccharide, RGP2, was isolated from Russula griseocarnosa and its immunostimulatory effects were confirmed in cyclophosphamide (CTX)-induced immunosuppressed mice. Following purification via chromatography, structural analysis revealed that RGP2 had a molecular weight of 11.82 kDa and consisted of glucose (Glc), galactose (Gal), mannose, glucuronic acid and glucosamine. Bond structure analysis and nuclear magnetic resonance characterization confirmed that the main chain of RGP2 was formed by →6)-ß-D-Glcp-(1→, →3)-ß-D-Glcp-(1→ and →6)-α-D-Galp-(1→, which was substituted at O-3 of →6)-ß-D-Glcp-(1→ by ß-D-Glcp-(1→. RGP2 was found to ameliorate pathological damage in the spleen and enhance immune cell activity in immunosuppressed mice. Based on combined multiomics analysis, RGP2 altered the abundance of immune-related microbiota (such as Lactobacillus, Faecalibacterium, and Bacteroides) in the gut and metabolites (uridine, leucine, and tryptophan) in the serum. Compared with immunosuppressed mice, RGP2 also restored the function of antigen-presenting cells, promoted the polarization of macrophages into the M1 phenotype, positively affected the differentiation of helper T cells, and inhibited regulatory T cell differentiation through the protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) pathway, ultimately exerting an immune boosting function. Overall, our findings highlight therapeutic strategies to alleviate CTX-induced immunosuppression in a clinical setting.


Assuntos
Basidiomycota , Diferenciação Celular , Glucanos , Animais , Camundongos , Basidiomycota/química , Glucanos/química , Glucanos/farmacologia , Glucanos/isolamento & purificação , Diferenciação Celular/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/química , Masculino , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Ciclofosfamida/farmacologia , Camundongos Endogâmicos BALB C , Microbioma Gastrointestinal/efeitos dos fármacos
3.
Cardiovasc Diabetol ; 23(1): 187, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822373

RESUMO

BACKGROUND: Ischemia and no obstructive coronary artery disease (INOCA) is increasingly recognized and associated with poor outcomes. The triglyceride-glucose (TyG) index is a reliable alternative measure of insulin resistance significantly linked to cardiovascular disease and adverse prognosis. We investigated the association between the TyG index and myocardial ischemia and the prognosis in INOCA patients. METHODS: INOCA patients who underwent both coronary angiography and myocardial perfusion imaging (MPI) were included consecutively. All participants were divided into three groups according to TyG tertiles (T1, T2, and T3). Abnormal MPI for myocardial ischemia in individual coronary territories was defined as summed stress score (SSS) ≥ 4 and summed difference score (SDS) ≥ 2. SSS refers to the sum of all defects in the stress images, and SDS is the difference of the sum of all defects between the rest images and stress images. All patients were followed up for major adverse cardiac events (MACE). RESULTS: Among 332 INOCA patients, 113 (34.0%) had abnormal MPI. Patients with higher TyG index had a higher rate of abnormal MPI (25.5% vs. 32.4% vs. 44.1%; p = 0.012). Multivariate logistic analysis showed that a high TyG index was significantly correlated with abnormal MPI in INOCA patients (OR, 1.901; 95% CI, 1.045-3.458; P = 0.035). During the median 35 months of follow-up, 83 (25%) MACE were recorded, and a higher incidence of MACE was observed in the T3 group (T3 vs. T2 vs. T1: 36.9% vs. 21.6% vs. 16.4%, respectively; p = 0.001). In multivariate Cox regression analysis, the T3 group was significantly associated with the risk of MACE compared to the T1 group (HR, 2.338; 95% CI 1.253-4.364, P = 0.008). CONCLUSION: This study indicates for the first time that the TyG index is significantly associated with myocardial ischemia and poor prognosis among INOCA patients.


Assuntos
Biomarcadores , Glicemia , Angiografia Coronária , Isquemia Miocárdica , Imagem de Perfusão do Miocárdio , Valor Preditivo dos Testes , Triglicerídeos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Triglicerídeos/sangue , Prognóstico , Isquemia Miocárdica/sangue , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/mortalidade , Isquemia Miocárdica/epidemiologia , Biomarcadores/sangue , Glicemia/metabolismo , Fatores de Risco , Medição de Risco , Estudos Retrospectivos , Fatores de Tempo , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/mortalidade , Resistência à Insulina
4.
Water Res ; 257: 121666, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38703543

RESUMO

Urban water distribution networks (WDNs) have wide range and intricate topology, which include leakage, pipe burst and other abnormal states during production and operation. With the continuous development of the Internet of Things (IoT) technology in recent years, the means of monitoring the WDNs by using wireless sensor network technology has gradually received attention and extensive research. Most of the existing researches select the deployment location of sensors according to the hydraulic state of the WDNs, but the connectivity and topology between the nodes of the WDNs are not fully considered and analyzed. In this study, a new method that can integrate the topological features and hydraulic model information of the WDN is proposed to solve the problem of optimal sensor placement. First, the method preprocesses the covariance matrix of the pressure sensitivity matrix of the water distribution network by a diffusion kernel-based data prefiltering method and obtains the new network topology weights and its Laplacian matrix under the constraints of the network topology through a data-based graphical Laplacian learning method. Then, the sensor placement problem is transformed into a matrix minimum eigenvalue constraint problem by the Graph Laplace Regularization (GLR)-based method, and finally the selection of sensor nodes is accomplished by the method based on Gershgorin Disc Alignment (GDA). The proposed strategy is tested on a passive Hanoi network, an active Net 3 network, and a larger network, PA2, and is compared with some existing methods. The results show that the proposed solution achieves good performance in three different leak localization methods.


Assuntos
Abastecimento de Água , Modelos Teóricos , Pressão , Algoritmos , Tecnologia sem Fio
5.
J Mol Cell Biol ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38323478

RESUMO

In eukaryotes, microtubule polymers are essential for cellular plasticity and fate decisions. End-binding (EB) proteins serve as scaffolds for orchestrating microtubule polymer dynamics and are essential for cellular dynamics and chromosome segregation in mitosis. Here, we show that EB1 forms molecular condensates with TIP150 and MCAK through liquid-liquid phase separation to compartmentalize the kinetochore-microtubule plus-end machinery, ensuring accurate kinetochore-microtubule interactions during chromosome segregation in mitosis. Perturbation of EB1-TIP150 polymer formation by a competing peptide prevents phase separation of the EB1-mediated complex and chromosome alignment at the metaphase equator in both cultured cells and Drosophila embryos. Lys220 of EB1 is dynamically acetylated by p300/CBP-associated factor in early mitosis, and persistent acetylation at Lys220 attenuates the phase separation of the EB1-mediated complex, dissolves droplets in vitro, and harnesses accurate chromosome segregation. Our data suggest a novel framework for understanding the organization and regulation of eukaryotic spindle for accurate chromosome segregation in mitosis.

6.
Front Neurol ; 15: 1272802, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38327620

RESUMO

Background: Congenital dysfibrinogenemia (CD) is a rare hereditary coagulation disorder resulting from mutations in fibrinogen genes. CD primarily presents with bleeding symptoms, but it can also lead to thrombotic events, including ischemic stroke. Case presentation: This report describes the case of a 52-year-old Chinese man who was admitted to the hospital twice due to recurrent cerebral infarction, characterized by sudden speech impairment and weakness in the right upper extremity. Brain MRI revealed multiple ischemic changes, predominantly in the left frontal and parietal lobes. Coagulation tests demonstrated reduced plasma fibrinogen (Clauss method), prolonged prothrombin time and thrombin time, and an elevated international normalized ratio. However, the ELISA assay indicated elevated levels of fibrinogen γ-chain protein. Despite a 2-month-old treatment regimen with aspirin, clopidogrel, and atorvastatin after the first hospitalization, the patient experienced a second ischemic stroke. Genetic analysis using whole-exome sequencing (WES) and Sanger sequencing identified a rare heterozygous missense variation, FGG c.952G>A (rs267606810), in both the stroke patient and his asymptomatic sister. Both individuals exhibited the same alterations in fibrinogen, characterized by reduced functional levels but increased antigenic protein. Subsequently, the patient was diagnosed with ischemic stroke associated with congenital dysfibrinogenemia. Conclusion: This case report expands the clinical phenotype spectrum associated with FGG c.952G>A (rs267606810) and underscores the significance of considering CD as a potential etiology for unexplained ischemic stroke, particularly in patients with a family history of coagulation disorders.

7.
J Mol Cell Biol ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200711

RESUMO

Accurate chromosome segregation in mitosis depends on kinetochores that connect centromeric chromatin to spindle microtubules. Centromeres are captured by individual microtubules via a kinetochore constitutive centromere-associated network (CCAN) during chromosome segregation. CCAN contains 16 subunits, including CENP-W and CENP-T. However, the molecular recognition and mitotic regulation of the CCAN assembly remain elusive. Here, we revealed that CENP-W binds to the histone fold domain and an uncharacterized N-terminal region of CENP-T. Aurora B phosphorylates CENP-W at Thr60, which enhances the interaction between CENP-W and CENP-T to ensure robust metaphase chromosome alignment and accurate chromosome segregation in mitosis. These findings delineate a conserved signaling cascade that integrates protein phosphorylation with CCAN integrity for the maintenance of genomic stability.

8.
Int J Biol Macromol ; 258(Pt 1): 128819, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104691

RESUMO

The water-soluble neutral polysaccharide BEP2, with a molecular weight of 26.65 kDa, was isolated from the aqueous extract obtained from the fruiting bodies of Boletus aereus Bull. BEP2 primarily comprises Gal, with specific site substitutions speculated at partial positions, such as the substitution of -OCH3 at position H-3 or the branch at position C-2 including α-L-Fucp-(1→, α-D-Manp-(1 â†’ and α-D-Manp-(1 â†’ 3)-α-L-Fucp-(1 â†’ 6)-ß-D-Glcp-(1→. Treatment with BEP2 significantly enhanced learning, memory, and cognitive function, while concurrently reducing the accumulation of ß-amyloid and suppressing neuroinflammation within the brains of APP/PS1 mice. Based on the results of biochemical detection, gut microbiota analysis, and metabolomic profiling, we found that BEP2 significantly upregulated the abundance of two bacterial families while downregulation that of seven bacterial families within the intestinal ecosystem. Notably, the abundance of the S24-7 family was significantly increased. Treatment with BEP2 upregulated five metabolites, while downregulating three metabolites, including norepinephrine. Additionally, BEP2 decreased the levels of interleukin (IL)-1ß and IL-6, regulated the activities of microglial cells and astrocytes and increased the levels of the chemokine fractalkine (CX3CL1) and its receptor on microglia (CX3CR1), as well as that of transforming growth factor (TGF)-ß1. These findings confirmed the suppressive effects of BEP2 on neuroinflammation.


Assuntos
Doença de Alzheimer , Basidiomycota , Humanos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Camundongos Transgênicos , Doenças Neuroinflamatórias , Ecossistema , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças
9.
Cell ; 186(26): 5892-5909.e22, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38091994

RESUMO

Different functional regions of brain are fundamental for basic neurophysiological activities. However, the regional specification remains largely unexplored during human brain development. Here, by combining spatial transcriptomics (scStereo-seq) and scRNA-seq, we built a spatiotemporal developmental atlas of multiple human brain regions from 6-23 gestational weeks (GWs). We discovered that, around GW8, radial glia (RG) cells have displayed regional heterogeneity and specific spatial distribution. Interestingly, we found that the regional heterogeneity of RG subtypes contributed to the subsequent neuronal specification. Specifically, two diencephalon-specific subtypes gave rise to glutamatergic and GABAergic neurons, whereas subtypes in ventral midbrain were associated with the dopaminergic neurons. Similar GABAergic neuronal subtypes were shared between neocortex and diencephalon. Additionally, we revealed that cell-cell interactions between oligodendrocyte precursor cells and GABAergic neurons influenced and promoted neuronal development coupled with regional specification. Altogether, this study provides comprehensive insights into the regional specification in the developing human brain.


Assuntos
Encéfalo , Transcriptoma , Humanos , Neurônios Dopaminérgicos , Neurônios GABAérgicos , Mesencéfalo , Neocórtex , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo
10.
Int J Nanomedicine ; 18: 7079-7092, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38050474

RESUMO

Background: Apoptosis resistance of hepatocellular carcinoma (HCC) often leads to treatment failure. Nonetheless, overcoming the resistance of HCC to apoptosis by inducing necroptosis of tumor cells to bypass the apoptotic pathway may be a promising treatment strategy. Sonodynamic therapy (SDT) has broad prospects in disease treatment because of its noninvasive characteristic and spatiotemporal control. The combination of SDT and shikonin in the treatment of HCC is expected to be a new tumor treatment method that can overcome apoptosis resistance. Methods: In this study, the antitumor effect was evaluated using normal liver cell line WRL68, HCC cell line HepG2 and HepG2 xenograft mouse models. Indocyanine green (ICG) was loaded on nanobubbles (NBs) to construct ICG-loaded nanobubbles (ICG-NBs). Combined sonosensitizer nanoplatforms with ultrasound (US) to achieve efficient SDT, the combination of SDT and shikonin in treating HCC can activate shikonin-induced necroptosis. As a result, tumor cells that produced apoptosis resistance were destroyed by necroptosis. Results: The results indicated a successful preparation of ICG-NBs with a uniform particle size of 273.0 ± 118.9 nm spherical structures. ICG-NB-mediated SDT, in combination with shikonin treatment, inhibited the viability, invasion, and migration of tumor cells. SDT + shikonin treatment group caused a substantial increase in necroptotic cells. The increased degree of tumor necrosis and the upregulated expression of receptor-interacting protein 3 kinase were observed in vivo studies, which indicated that the antitumor effect was accompanied by enhanced necroptosis in the SDT + shikonin treatment group. Conclusion: ICG-NB-mediated SDT combined with shikonin inhibits the growth of HCC by increasing the necroptosis of tumor cells. Therefore, this combination therapy is a promising treatment strategy against the specific cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Camundongos , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Necroptose , Linhagem Celular Tumoral , Neoplasias Hepáticas/tratamento farmacológico , Apoptose , Verde de Indocianina/farmacologia , Espécies Reativas de Oxigênio/metabolismo
11.
Nutrients ; 15(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38068869

RESUMO

BACKGROUND: The edible fungus Auricularia delicate (ADe) is commonly employed in traditional medicine for intestinal disorders; however, its inhibitory effect on colitis-associated colorectal cancer (CAC) and the underlying mechanisms remain unexplored. (2) Methods: The inhibitory effect of ADe on CAC was investigated using a mouse model induced by azoxymethane/dextran sulfate sodium. RESULTS: ADe effectively suppressed the growth and number of intestinal tumors in mice. Intestinal microbiota analyses revealed that ADe treatment increased Akkermansia and Parabacteroides while it decreased Clostridium, Turicibacter, Oscillospira, and Desulfovibrio. ADe regulated the levels of 2'-deoxyridine, creatinine, 1-palmitoyl lysophosphatidylcholine, and choline in serum. Furthermore, the levels of these metabolites were associated with the abundance of Oscillospira and Paraacteroides. ADe up-regulated the free fatty acid receptor 2 and ß-Arrestin 2, inhibited the nuclear factor kappa B (NF-κB) pathway, and significantly attenuated the levels of inflammatory cytokines, thereby mitigating the inflammatory in CAC mice. CONCLUSIONS: The protective effect of ADe in CAC mice is associated with the regulation of intestinal microbiota, which leads to the inhibition of NF-kB pathway and regulation of inflammation.


Assuntos
Neoplasias Associadas a Colite , Colite , Microbioma Gastrointestinal , Animais , Camundongos , Colite/induzido quimicamente , Colite/complicações , Colite/microbiologia , Auricularia/metabolismo , Inflamação/metabolismo , NF-kappa B/metabolismo , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Colo/metabolismo
12.
Int J Nanomedicine ; 18: 6199-6212, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37933299

RESUMO

Purpose: Sonodynamic therapy (SDT) is a promising and significant measure for the treatment of tumors. However, the internal situation of hepatocellular carcinoma (HCC) is complex, separate SDT treatment is difficult to play a good therapeutic effect. Here, we used SDT combined with MG-132 to mediate apoptosis and autophagy of HCC cells to achieve the purpose of treatment of cancer. Methods: To determine the generated reactive oxygen species (ROS) and the change of mitochondrial membrane potential (ΔΨm), HepG2 cells were stained by 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) and 5,5',6,6'-Tetrachloro-1,1',3,3'-tetraethyl-imidacarbocyanine iodide (JC-1) staining to determine the IR-820@NBs-mediated SDT to achieve HCC therapy through the mitochondrial pathway. Cell counting kit 8 (CCK-8) assay and flow cytometry were used to detect cell viability and apoptosis rate of HepG2 cells. Autophagy was detected by mCherry-GFP-LC3B fluorescence labeling. Chloroquine (Cq) pretreatment was used to explore the relationship between autophagy and apoptosis. To detect the ability of HepG2 cells migration and invasion, cell scratch assay and transwell assay were used. Results: The successfully prepared IR-820@NBs could effectively overcome the shortcomings of IR-820 and induce lethal levels of ROS by ultrasound irradiation. As a dual agonist of apoptosis and autophagy, MG-132 could effectively enhance the efficacy of SDT in the process of treating HCC. After pre-treatment with Cq, the cell activity increased and the level of apoptosis decreased, which proved that apoptosis and autophagy were induced by combined therapy, autophagy, and apoptosis have the synergistic anti-tumor effect, and part of apoptosis was autophagy-dependent. After combined therapy, the activity and invasive ability of HCC cells decreased significantly. Conclusion: SDT combined with MG-132 in the process of treating liver cancer could effectively induce apoptosis and autophagy anti-tumor therapy, which is helpful to the research of new methods to treat liver cancer.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Terapia por Ultrassom , Humanos , Carcinoma Hepatocelular/terapia , Terapia por Ultrassom/métodos , Neoplasias Hepáticas/terapia , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Linhagem Celular Tumoral , Autofagia
13.
Int J Nanomedicine ; 18: 6059-6073, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908671

RESUMO

Background: Despite the clinical efficacy of immunotherapy in treating malignant tumors, its effectiveness is often hampered by the immunosuppressive nature of the tumor microenvironment (TME). In this study, we propose the design of a nanoscale ultrasound contrast agent capable of triggering macrophage polarization and immunogenic cell death (ICD) for the treatment of hepatocellular carcinoma (HCC) through sonodynamic treatment (SDT) and immunotherapy. Methods: The re-educator (designated as ICG@C3F8-R848 NBs) is composed of the Toll-like receptor agonist resiquimod (R848) and the sonosensitizer Indocyanine green (ICG), utilizing nanobubbles (NBs) as carriers. The technique known as ultrasound-targeted nanobubble destruction (UTND) employs nanosized microbubbles and low-frequency ultrasound (LFUS) to ensure accurate drug delivery and enhance safety. Results: Following intravenous delivery, ICG@C3F8-R848 NBs have the potential to selectively target and treat primary tumors using SDT in conjunction with ultrasonography. Importantly, R848 can enhance antitumor immunity by inducing the polarization of macrophages from an M2 to an M1 phenotype. Conclusion: The SDT-initiated immunotherapy utilizing ICG@C3F8-R848 NBs demonstrates significant tumor suppression effects with minimal risk of systemic toxicity. The utilization of this self-delivery re-education technique would contribute to advancing the development of nanomedicine for the treatment of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Sistemas de Liberação de Medicamentos/métodos , Imunoterapia/métodos , Verde de Indocianina/farmacologia , Microambiente Tumoral , Linhagem Celular Tumoral
14.
J Mol Cell Biol ; 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37777834

RESUMO

Shugoshin-1 (Sgo1) is necessary for maintaining sister centromere cohesion and ensuring accurate chromosome segregation during mitosis. It has been reported that the localization of Sgo1 at the centromere is dependent on Bub1-mediated phosphorylation of histone H2A at T120. However, it remains uncertain whether other centromeric proteins play a role in regulating the localization and function of Sgo1 during mitosis. Here, we show that CENP-A interacts with Sgo1 and determines the localization of Sgo1 to the centromere during mitosis. Further biochemical characterization revealed that lysine and arginine residues in the C-terminal domain of Sgo1 are critical for binding CENP-A. Interestingly, the replacement of these basic amino acids with acidic amino acids perturbed the localization of Sgo1 and Aurora B to the centromere, resulting in aberrant chromosome segregation and premature chromatid separation. Taken together, these findings reveal a previously unrecognized but direct link between Sgo1 and CENP-A in centromere plasticity control and illustrate how the Sgo1-CENP-A interaction guides accurate cell division.

15.
Lipids Health Dis ; 22(1): 175, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853441

RESUMO

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder. The primary objective of this study was to identify the major pathogenic mutations in a Chinese family with FH. METHODS: Whole-genome sequencing (WGS) was used to identify variants of FH-related genes, including low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9). Bioinformatics software was used to predict signal peptides, transmembrane structures, and spatial construction information of the mutated sequences. Western blotting was performed on the mutant protein to determine the presence of the major structural domains of the LDLR. The PCSK9 and APOB genes were screened and analyzed. Moreover, the proband and his brother were treated with a PCSK9 inhibitor for 1 year, and the effect of the treatment on lipid levels was assessed. RESULTS: WGS revealed two potentially pathogenic mutations in the LDLR gene. One was a novel mutation, c.497delinsGGATCCCCCAGCTGCATCCCCCAG (p. Ala166fs), and the other was a known pathogenic mutation, c.2054C>T (p. Pro685Leu). Bioinformatics prediction and in vitro experiments revealed that the novel mutation could not be expressed on the cell membrane. Numerous gene variants were identified in the APOB gene that may have a significant impact on the family members with FH. Thus, it is suggested that the severe manifestation of FH in the proband primarily resulted from the cumulative genetic effects of variants in both LDLR and APOB. However, a subsequent study indicated that treatment with a PCSK9 inhibitor (Evolocumab) did not significantly reduce the blood lipid levels in the proband or his brother. CONCLUSIONS: The cumulative effect of LDLR and APOB variants was the primary cause of elevated blood lipid levels in this family. However, PCSK9 inhibitor therapy did not appear to be beneficial for the proband. This study emphasizes the importance of genetic testing in determining the most suitable treatment options for patients with FH.


Assuntos
Apolipoproteínas B , Hiperlipoproteinemia Tipo II , Pró-Proteína Convertase 9 , Receptores de LDL , Humanos , Masculino , Apolipoproteínas B/genética , População do Leste Asiático/genética , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/genética , Lipídeos , Mutação , Pró-Proteína Convertase 9/genética , Receptores de LDL/genética , Testes Genéticos
16.
Nutrients ; 15(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37686830

RESUMO

Alzheimer's disease (AD) is prone to onset and progression under oxidative stress conditions. Hericium coralloides (HC) is an edible medicinal fungus that contains various nutrients and possesses antioxidant properties. In the present study, the nutritional composition and neuroprotective effects of HC on APP/PS1 mice were examined. Behavioral experiments showed that HC improved cognitive dysfunction in APP/PS1 mice. Immunohistochemical and Western blotting results showed that HC reduced the levels of p-tau and amyloid-ß deposition in the brain. By altering the composition of the gut microbiota, HC promoted the growth of short-chain fatty acid-producing bacteria and suppressed the growth of Helicobacter. Metabolomic results showed that HC decreased D-glutamic acid and oxidized glutathione levels. In addition, HC reduced the levels of reactive oxygen species, enhanced the secretion of superoxide dismutase, catalase, and glutathione peroxidase, inhibited the production of malondialdehyde and 4-hydroxynonenal, and activated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. Collectively, HC demonstrated antioxidant activity by activating Nrf2 signaling and regulating gut microbiota, further exerting neuroprotective effects. This study confirms that HC has the potential to be a clinically effective AD therapeutic agent and offers a theoretical justification for both the development and use of this fungus.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Microbioma Gastrointestinal , Fármacos Neuroprotetores , Animais , Camundongos , Fator 2 Relacionado a NF-E2 , Doença de Alzheimer/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Antioxidantes/farmacologia
17.
Cytokine Growth Factor Rev ; 73: 135-149, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37543438

RESUMO

In the tumor microenvironment (TME), exosomes secreted by cells form interactive networks between the tumor cells and immune cells, thereby regulating immune signaling cascades in the TME. As key messengers of cell-to-cell communication in the TME, exosomes not only take charge of tumor cell antigen presentation to the immune cells, but also regulate the activities of immune cells, inhibit immune function, and, especially, promote immune resistance, all of which affects the therapeutic outcomes of tumors. Exosomes, which are small-sized vesicles, possess some remarkable advantages, including strong biological activity, a lack of immunogenicity and toxicity, and a strong targeting ability. Based on these characteristics, research on exosomes as biomarkers or carriers of tumor therapeutic drugs has become a research hotspot in related fields. This review describes the role of exosomes in cell communications in the TME, summarizes the effectiveness of exosome-based immunotherapy in overcoming immune resistance in cancer treatment, and systematically summarizes and discusses the characteristics of exosomes from different cell sources. Furthermore, the prospects and challenges of exosome-related therapies are discussed.

18.
Theranostics ; 13(9): 2879-2895, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284442

RESUMO

Background: Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug for chronic alcohol addiction, has anti-inflammatory effects that help prevent various cancers, and Cu2+ can enhance the effects of DSF. Inflammatory bowel diseases (IBD) are characterized by chronic or recurrent relapsing gastrointestinal inflammation. Many drugs targeting the immune responses of IBD have been developed, but their application has many problems, including side effects and high costs. Therefore, there is an urgent need for new drugs. In this study, we investigated the preventive effects of DSF+Cu2+ on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. Methods: The anti-inflammatory effects were investigated using the DSS-induced colitis mouse model and lipopolysaccharide (LPS)-induced macrophages. DSS-induced TCRß-/- mice were used to demonstrate the effect of DSF in conjunction with Cu2+ on CD4+ T cell-secreted interleukin 17 (IL-17). In addition, the effect of DSF+Cu2+ on intestinal flora was studied by 16S rRNA microflora sequencing. Results: DSF and Cu2+ could significantly reverse the symptom of DSS-induced UC in mice, such as weight loss, disease activity index score, colon length shortening, and reversal of colon pathological changes. DSF and Cu2+ could inhibit colonic macrophage activation by blocking the nuclear factor kappa B (NF-κB) pathway, reducing nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3)-inflammasome-derived interleukin 1 beta (IL-1ß) secretion and caspase-1 (CASP1) activation, and decreasing IL-17 secretion by CD4+ T cells. Moreover, the treatment of DSF and Cu2+ could protect the intestinal barrier by reversing the expression of tight junction proteins, zonula occluden-1 (ZO-1), occludin, and mucoprotein-2 (MUC2). Additionally, DSF+Cu2+ could reduce the abundance of harmful bacteria and increase beneficial bacteria in the intestinal tract of mice, effectively improving intestinal microecology. Conclusion: Our study evaluated the effect of DSF+Cu2+ on the immune system and gut microbiota in colonic inflammation and highlighted its potential to treat UC in the clinic.


Assuntos
Colite Ulcerativa , Colite , Doenças Inflamatórias Intestinais , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Dissulfiram/farmacologia , Sulfato de Dextrana/toxicidade , Interleucina-17/metabolismo , RNA Ribossômico 16S/metabolismo , Colite/induzido quimicamente , Colo/patologia , NF-kappa B/metabolismo , Inflamação/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
20.
J Mol Cell Biol ; 15(6)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37365681

RESUMO

In mitosis, accurate chromosome segregation depends on the kinetochore, a supermolecular machinery that couples dynamic spindle microtubules to centromeric chromatin. However, the structure-activity relationship of the constitutive centromere-associated network (CCAN) during mitosis remains uncharacterized. Building on our recent cryo-electron microscopic analyses of human CCAN structure, we investigated how dynamic phosphorylation of human CENP-N regulates accurate chromosome segregation. Our mass spectrometric analyses revealed mitotic phosphorylation of CENP-N by CDK1, which modulates the CENP-L-CENP-N interaction for accurate chromosome segregation and CCAN organization. Perturbation of CENP-N phosphorylation is shown to prevent proper chromosome alignment and activate the spindle assembly checkpoint. These analyses provide mechanistic insight into a previously undefined link between the centromere-kinetochore network and accurate chromosome segregation.


Assuntos
Proteína Quinase CDC2 , Proteínas Cromossômicas não Histona , Segregação de Cromossomos , Humanos , Proteína Quinase CDC2/metabolismo , Centrômero/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Cinetocoros/metabolismo , Mitose , Fosforilação
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