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/metabolismoRESUMO
Moso bamboo (Phyllostachys edulis) shows remarkably rapid growth (114.5 cm/day), but the underlying biological mechanisms remain unclear. After examining more than 12,750 internodes from more than 510 culms from 17 Moso populations, we identified internode 18 as a representative internode for rapid growth. This internode includes a 2-cm cell division zone (DZ), a cell elongation zone up to 12 cm, and a secondary cell wall (SCW) thickening zone. These zones elongated 11.8 cm, produced approximately 570,000,000 cells, and deposited â¼28 mg g-1 dry weight (DW) lignin and â¼44 mg g-1 DW cellulose daily, far exceeding vegetative growth observed in other plants. We used anatomical, mathematical, physiological, and genomic data to characterize development and transcriptional networks during rapid growth in internode 18. Our results suggest that (1) gibberellin may directly trigger the rapid growth of Moso shoots, (2) decreased cytokinin and increased auxin accumulation may trigger cell DZ elongation, and (3) abscisic acid and mechanical pressure may stimulate rapid SCW thickening via MYB83L. We conclude that internode length involves a possible tradeoff mediated by mechanical pressure caused by rapid growth, possibly influenced by environmental temperature and regulated by genes related to cell division and elongation. Our results provide insight into the rapid growth of Moso bamboo.
Assuntos
Giberelinas , Transcriptoma , Ácido Abscísico/farmacologia , Citocininas , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Lignina , Poaceae/genética , Transcriptoma/genéticaRESUMO
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 InsulinaRESUMO
BACKGROUND: Prediabetes is common and associated with poor prognosis in patients with acute coronary syndrome and those undergoing revascularization. However, the impact of prediabetes on prognosis in patients with coronary intermediate lesions remains unclear. The objective of the current study is to explore the impact of prediabetes and compare the prognostic value of the different definitions of prediabetes in patients with coronary intermediate lesions. METHODS: A total of 1532 patients attending Fuwai hospital (Beijing, China), with intermediate angiographic coronary lesions, not undergoing revascularization, were followed-up from 2013 to 2021. Patients were classified as normal glucose tolerance (NGT), prediabetes and diabetes according to various definitions based on HbA1c or admission fasting plasma glucose (FPG). The primary endpoint was defined as major adverse cardiovascular events (MACE), the composite endpoint of all-cause death, non-fatal myocardial infarction and repeated revascularization therapy. Multivariate cox regression model was used to explore the association between categories of abnormal glucose category and MACE risk. RESULTS: The proportion of patients defined as prediabetes ranged from 3.92% to 47.06% depending on the definition used. A total of 197 MACE occurred during a median follow-up time of 6.1 years. Multivariate cox analysis showed that prediabetes according to the International Expert Committee (IEC) guideline (6.0 ≤ HbA1c < 6.5%) was associated with increased risk of MACE compared with NGT (hazard ratio [HR]: 1.705, 95% confidence interval [CI] 1.143-2.543) and after confounding adjustment (HR: 1.513, 95%CI 1.005-2.277). Consistently, the best cut-off point of glycated haemoglobin (HbA1c) identified based on the Youden's index was also 6%. Restricted cubic spline analysis delineated a linear positive relationship between baseline HbA1c and MACE risk. Globally, FPG or FPG-based definition of prediabetes was not associated with patients' outcome. CONCLUSIONS: In this cohort of patients with intermediate coronary lesions not undergoing revascularization therapy, prediabetes based on the IEC-HbA1c definition was associated with increased MACE risk compared with NGT, and may assist in identifying high-risk patients who can benefit from early lifestyle intervention.
Assuntos
Glicemia , Estado Pré-Diabético , Humanos , Hemoglobinas Glicadas , Estudos Prospectivos , Fatores de Risco , JejumRESUMO
INTRODUCTION: Hypertensive nephropathy is characterized by glomerular and tubulointerstitial damage, but we know little about changes in cell-specific gene expression in the early stages of hypertensive kidney injury, which usually has no obvious pathological changes. METHODS: We performed unbiased single-cell RNA sequencing of rat kidney samples from hypertensive kidney injury to generate 10,602 single-cell transcriptomes from 2 control and 2 early stage hypertensive kidney injury samples. RESULTS: All major cell types of the kidney were represented in the final dataset. Side-by-side comparisons showed that cell type-specific changes in gene expression are critical for functional impairment of glomeruli and tubules and activation of immune cells. In particular, we found a significantly reduced gene expression profile of maintaining vascular integrity in glomerular cells of hypertensive kidney injury. Meanwhile, the expression of genes associated with oxidative stress injury and fibrosis in the renal tubules and collecting ducts was elevated, but the degree of tubular cells response to injury differed between parts. We also found a signature of immune cell infiltration in hypertensive kidney injury. CONCLUSION: Exploring the changes of gene expression in hypertension-injured kidneys may be helpful to identify the early biomarkers and signal pathways of this disease. Our data provide rich resources for understanding the pathogenesis of hypertensive renal injury and formulating effective treatment strategies.
Assuntos
Hipertensão Renal , Hipertensão , Ratos , Animais , Transcriptoma , Rim/patologia , Hipertensão/complicações , Hipertensão Renal/complicações , Hipertensão Essencial/complicaçõesRESUMO
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 GenéticosRESUMO
Selenium (Se) is in great demand as a health supplement due to its superior reactivity and excellent bioavailability, despite selenium nanoparticles (SeNPs) having signs of minor toxicity. At present, the efficiency of preparing SeNPs using lactic acid bacteria is unsatisfactory. Therefore, a probiotic bacterial strain that is highly efficient at converting selenite to elemental selenium is needed. In our work, four selenite-reducing bacteria were isolated from soil samples. Strain LAB-Se2, identified as Pediococcus acidilactici DSM20284, had a reduction rate of up to 98% at ambient temperature. This strain could reduce 100 mg L-1 of selenite to elemental Se within 48 h at pH 4.5-6.0, a temperature of 30-40 °C, and a salinity of 1.0-6.5%. The produced SeNPs were purified, freeze-dried, and subsequently systematically characterised using FTIR, DSL, SEM-EDS, and TEM techniques. SEM-EDS analysis proved the presence of selenium as the foremost constituent of SeNPs. The strain was able to form spherical SeNPs, as determined by TEM. In addition, DLS analysis confirmed that SeNPs were negatively charged (-26.9 mV) with an average particle size of 239.6 nm. FTIR analysis of the SeNPs indicated proteins and polysaccharides as capping agents on the SeNPs. The SeNPs synthesised by P. acidilactici showed remarkable antibacterial activity against E. coli, B. subtilis, S. aureus, and K. pneumoniae with inhibition zones of 17.5 mm, 13.4 mm, 27.9 mm, and 16.2 mm, respectively; they also showed varied MIC values in the range of 15-120 µg mL-1. The DPPH, ABTS, and hydroxyl, and superoxide scavenging activities of the SeNPs were 70.3%, 72.8%, 95.2%, and 85.7%, respectively. The SeNPs synthesised by the probiotic Lactococcus lactis have the potential for safe use in biomedical and nutritional applications.
Assuntos
Nanopartículas , Pediococcus acidilactici , Selênio , Selênio/química , Ácido Selenioso/química , Pediococcus acidilactici/metabolismo , Escherichia coli/metabolismo , Staphylococcus aureus/metabolismo , Nanopartículas/químicaRESUMO
BACKGROUND: RET fusions are rare oncogenic drivers in non-small cell lung cancer (NSCLC). While activating RET rearrangements are found in NSCLC patients harboring epidermal growth factor receptor (EGFR) genetic alterations at resistance to EGFR inhibitors, the extent to which co-occurring genomic alterations exist and how they might affect prognosis or therapy response is poorly understood. METHODS: Targeted next-generation sequencing (NGS) was used to assess 380 baseline patients with primary RET fusions and 71 EGFR-mutated NSCLC patients who acquired RET fusions after developing resistance to EGFR-tyrosine kinase inhibitors (EGFR-TKIs). RESULTS: Primary RET fusions were more likely associated with females and younger age, with KIF5B being the predominant fusion partner. In baseline patients, both SMAD4 (5.3% vs. 0.0%, P = 0.044) and MYC copy-number gain variants (6.9% vs. 0.0%, P = 0.009) were more frequently co-mutated with KIF5B-RET than CCDC6-RET. By contrast, CDKN2A (11.3% vs. 2.4%, P = 0.003) mutations were significantly enriched in CCDC6-RET-rearranged baseline patients. A significant increase in the proportion of CCDC6-RET was observed in acquired RET-rearranged patients (47.3% vs. 22.5%, P < 0.001). The median progression-free survival (PFS) of patients harboring RB1 and TP53 double-mutations (5.5 vs. 10.0 months, P = 0.020) or ERBB2 amplification (5.6 vs. 10.0 months, P = 0.041) was significantly shorter than the wild-type counterparts. Moreover, we identified that RET fusions were more likely associated with acquired resistance (AR) to third-generation EGFR-TKIs than previous generations of EGFR-TKIs. CONCLUSIONS: In conclusion, we depicted the mutational profiles of NSCLC patients who harbor RET fusions at baseline or after resistance to EGFR-TKIs. Furthermore, our results suggest that RET fusions mediate secondary resistance to third-generation EGFR-TKIs and might be associated with poor prognosis in patients with NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas c-ret/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Oncogenes , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-ret/metabolismoRESUMO
Bamboo differentiates a cell division zone (DZ) and a cell elongation zone (EZ) to promote internode elongation during rapid growth. However, the biological mechanisms underlying this sectioned growth behavior are still unknown. Using histological, physiological, and genomic data, we found that the cell wall and other subcellular organelles such as chloroplasts are more developed in the EZ. Abundant hydrogen peroxide accumulated in the pith cells of the EZ, and stomata formed completely in the EZ. In contrast, most cells in the DZ were in an undifferentiated state with wrinkled cell walls and dense cytoplasm. Hormone detection revealed that the levels of gibberellin, auxin, cytokinin, and brassinosteroid were higher in the DZ than in the EZ. However, the levels of salicylic acid and jasmonic acid were higher in the EZ than in the DZ. Transcriptome analysis with qRT-PCR quantification revealed that the transcripts for cell division and primary metabolism had higher expression in the DZ, whereas the genes for photosynthesis, cell wall growth, and secondary metabolism were dramatically upregulated in the EZ. Overexpression of a MYB transcription factor, BmMYB83, promotes cell wall lignification in transgenic plants. BmMYB83 is specifically expressed in cells that may have lignin deposits, such as protoxylem vessels and fiber cells. Our results indicate that hormone gradient and transcriptome reprogramming, as well as specific expression of key genes such as BmMYB83, may lead to differentiation of cell growth in the bamboo internode.
Assuntos
Regulação da Expressão Gênica de Plantas , Giberelinas , Lignina/metabolismo , Brassinosteroides , Peróxido de Hidrogênio/metabolismo , Ácidos Indolacéticos , Fatores de Transcrição/metabolismo , Citocininas , Ácido Salicílico , Hormônios , Diferenciação Celular/genéticaRESUMO
BACKGROUND: Ras activation is a frequent event in hepatocellular carcinoma (HCC). Combining a RAS inhibitor with traditional clinical therapeutics might be hampered by a variety of side effects, thus hindering further clinical translation. Herein, we report on integrating an IR820 nanocapsule-augmented sonodynamic therapy (SDT) with the RAS inhibitor farnesyl-thiosalicylic acid (FTS). Using cellular and tumor models, we demonstrate that combined nanocapsule-augmented SDT with FTS induces an anti-tumor effect, which not only inhibits tumor progression, and enables fluorescence imaging. To dissect the mechanism of a combined tumoricidal therapeutic strategy, we investigated the scRNA-seq transcriptional profiles of an HCC xenograft following treatment. RESULTS: Integrative single-cell analysis identified several clusters that defined many corresponding differentially expressed genes, which provided a global view of cellular heterogeneity in HCC after combined SDT/FTS treatment. We conclude that the combination treatment suppressed HCC, and did so by inhibiting endothelial cells and a modulated immunity. Moreover, hepatic stellate secretes hepatocyte growth factor, which plays a key role in treating SDT combined FTS. By contrast, enrichment analysis estimated the functional roles of differentially expressed genes. The Gene Ontology terms "cadherin binding" and "cell adhesion molecule binding" and KEGG pathway "pathway in cancer" were significantly enriched by differentially expressed genes after combined SDT/FTS therapy. CONCLUSIONS: Thus, some undefined mechanisms were revealed by scRNA-seq analysis. This report provides a novel proof-of-concept for combinatorial HCC-targeted therapeutics that is based on a non-invasive anti-tumor therapeutic strategy and a RAS inhibitor.
Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Diatermia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Análise de Sequência de RNA , Proteínas ras/antagonistas & inibidores , Animais , Carcinoma Hepatocelular/radioterapia , Linhagem Celular Tumoral , Terapia Combinada , Modelos Animais de Doenças , Células Endoteliais , Farneseno Álcool/análogos & derivados , Farneseno Álcool/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/radioterapia , Camundongos Endogâmicos BALB C , Camundongos Nus , SalicilatosRESUMO
Long non-coding RNA (LncRNA) DUXAP9 expression was recently found to be higher in hepatocellular carcinoma (HCC) tissues and cells, and correlated with a shorter overall survival of HCC patients. However, its roles in HCC progression have never been revealed. Here, the roles of DUXAP9 in HCC cell stemness are explored as cancer stem cells (CSCs) contribute to one of the root of cancer progression. We found that DUXAP9 positively regulated HCC cell stemness, as characterized by the change of sphere-formation ability, ALDH activity and stemness marker expression. Further luciferase reporter, mRNA stability and RNA-RNA in vitro interaction assays indicated that DUXAP9 directly bound to the 3' untranslated region (UTR) of sox9, enhanced the mRNA stability of sox9 and thus increased sox9 expression. Notably, the effects induced by DUXAP9 on HCC cell stemness depended on sox9 expression. Therefore, this work identifies a novel DUXAP9/sox9 axis essential for HCC cell stemness.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Células-Tronco Neoplásicas , RNA Longo não Codificante , Fatores de Transcrição SOX9 , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , Fatores de Transcrição SOX9/genéticaRESUMO
BACKGROUND: Endoplasmic reticulum (ER) stress is involved in the progression of Alzheimer's disease (AD). Verbascoside (VB), an active phenylethanoid glycoside that was first isolated from Verbascum sinuatum (the wavyleaf mullein), possesses anti-inflammatory, antioxidative, and anti-apoptotic effects. The purpose of this study was to elucidate the beneficial effects of VB in amyloid ß (Aß)1-42-damaged human glioma (U251) cells and in APPswe/PSEN1dE9 transgenic (APP/PS1) mice. METHODS: U251 cells were co-incubated with 10 µM of Aß1-42 and treated with VB. The protective effects of VB were investigated by using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide assay, flow cytometry, fluorescence staining, and transmission electron microscopy. APP/PS1 transgenic mice were treated for 6 weeks with VB. Learning and memory were evaluated using a Morris water maze test. Immunohistochemistry, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling, thioflavin-S staining, and proteomics analysis were performed to study the potential neuroprotective mechanism. Enzyme-linked immunosorbent assays and western blot were performed to analyze altered protein levels of brain lysates in APP/PS1 mice and/or Aß1-42-damaged U251 cells. RESULTS: In Aß1-42-damaged U251 cells, VB significantly improved cell viability, inhibited apoptosis, reduced calcium accumulation and the intracellular concentrations of reactive oxygen species, and improved the morphology of mitochondria and ER. In APP/PS1 mice, 6-week administration of VB significantly improved memory and cognition. VB inhibited apoptosis, reduced the deposition of Aß, reduced the formation of neurofibrillary tangles formed by hyperphosphorylated tau protein, and downregulated the expression levels of 4-hydroxynonenal and mesencephalic astrocyte-derived neurotrophic factor in the brains of APP/PS1 mice. Proteomics analysis of mouse hippocampus suggested that the neuroprotective effect of VB may be related to the reduction of ER stress. This was indicated by the fact that VB inhibited the three branches of the unfolded protein response, thereby attenuating ER stress and preventing apoptosis. CONCLUSIONS: The results confirmed that VB possesses significant neuroprotective effects, which are related to the reduction of ER stress. These findings support the status of VB as a potentially effective treatment for AD and warrant further research.
Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glucosídeos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/toxicidade , Fenóis/uso terapêutico , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Estresse do Retículo Endoplasmático/fisiologia , Glucosídeos/farmacologia , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Masculino , Camundongos , Camundongos Transgênicos , Fármacos Neuroprotetores/farmacologia , Fenóis/farmacologia , Presenilina-1/genéticaRESUMO
Improving mitochondrial dysfunction and inhibiting apoptosis has always been regarded as a treatment strategy for Alzheimer's disease (AD). Isoforsythiaside (IFY), a phenylethanoid glycoside isolated from the dried fruit of Forsythia suspensa, displays antioxidant activity. This study examined the neuroprotective effects of IFY and its underlying mechanisms. In the L-glutamate (L-Glu)-induced apoptosis of HT22 cells, IFY increased cell viability, inhibited mitochondrial apoptosis, and reduced the intracellular levels of reactive oxygen species (ROS), caspase-3, -8 and -9 after 3 h of pretreatment and 12-24 h of co-incubation. In the APPswe/PSEN1dE9 transgenic (APP/PS1) model, IFY reduced the anxiety of mice, improved their memory and cognitive ability, reduced the deposition of beta amyloid (Aß) plaques in the brain, restrained the phosphorylation of the tau protein to form neurofibrillary tangles, inhibited the level of 4-hydroxynonenal in the brain, and improved phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway-related mitochondrial apoptosis. In Aß1-42-induced U251 cells, IFY relieved the mitochondrial swelling, crest ruptures and increased their electron density after 3 h of pretreatment and 18-24 h of co-incubation. The improved cell viability and mitochondrial function after IFY incubation was blocked by the synthetic PI3K inhibitor LY294002. Taken together, these results suggest that IFY exerts a protective effect against AD by enhancing the expression levels of anti-apoptosis proteins and reducing the expression levels of pro-apoptosis proteins of B-cell lymphoma-2 (BCL-2) family members though activating the PI3K/AKT pathway.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Ácidos Cafeicos/uso terapêutico , Glucosídeos/uso terapêutico , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Peptídeos beta-Amiloides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal , Ácidos Cafeicos/farmacologia , Linhagem Celular , Cognição/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Glucosídeos/farmacologia , Ácido Glutâmico/farmacologia , Hipocampo/metabolismo , Camundongos , Mitocôndrias/efeitos dos fármacos , Presenilina-1/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Nanoparticles based on the heavy chain of the human ferritin (HFn) are arousing growing interest in the field of drug delivery due to their exceptional characteristics. However, the unsatisfied plasma half life of HFn substantially limits its application as a delivery platform for antitumor agents. Herein we fused an albumin binding domain (ABD) variant that basically derives from the streptococcal protein G and possesses a long-acting characteristic in serum albumin to the N-terminus of the HFn for the aim of half-life extension. This ABD-HFn construct was highly expressed and fully self-assembled into symmetrical and spherical structure in E. coli bacteria. The purified ABD-HFn showed a similar particle size with wild-type HFn and also exhibited an extremely high binding affinity with human serum albumin. To evaluate the therapeutic potential of this ABD-HFn construct in terms of half-life extension, we encapsulated a model antitumor agent doxorubicin (DOX) into the ABD-HFn. Significantly outstanding loading efficacy of above 60 molecules doxorubicin for each ABD-HFn cage was achieved. The doxorubicin-loaded ABD-HFn nanoparticle was characterized and further compared with the recombinant HFn counterpart. The ABD-HFn/DOX nanoparticle showed dramatically improved stability and comparable cell uptake rate when compared with HFn/DOX counterpart. Pharmacokinetics study in Sprague-Dawley rats showed that ABD-HFn/DOX nanoparticle possessed significantly prolonged plasma half life of â¼17.2 h, exhibiting nearly 19 times longer than that of free doxorubicin and 12 times for HFn/DOX. These optimal results indicated that fusion with ABD will be a promising strategy to extend the half life for protein-based nanoparticles.
Assuntos
Doxorrubicina , Portadores de Fármacos , Ferritinas , Proteínas Recombinantes de Fusão , Albumina Sérica Humana , Células A549 , Animais , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Ferritinas/química , Ferritinas/farmacocinética , Ferritinas/farmacologia , Meia-Vida , Humanos , Domínios Proteicos , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/farmacocinética , Proteínas Recombinantes de Fusão/farmacologia , Albumina Sérica Humana/química , Albumina Sérica Humana/farmacocinética , Albumina Sérica Humana/farmacologiaRESUMO
Evodiamine (Evo), a major alkaloid compound isolated from the dry unripened fruit of Evodia fructus, has a wide range of pharmacological activities. The present study sought to explore the neuroprotective effects of Evo in l-glutamate (l-Glu)-induced apoptosis of HT22 cells, and in a d-galactose and aluminum trichloride-developed Alzheimer’s disease (AD) mouse model. Evo significantly enhanced cell viability, inhibited the accumulation of reactive oxygen species, ameliorated mitochondrial function, increased the B-cell lymphoma-2 protein content, and inhibited the high expression levels of Bax, Bad, and cleaved-caspase-3 and -8 in l-Glu-induced HT22 cells. Evo also enhanced the phosphorylation activities of protein kinase B and the mammalian target of rapamycin in the l-Glu-induced HT22 cells. In the AD mouse model, Evo reduced the aimless and chaotic movements, reduced the time spent in the central area in the open field test, and decreased the escape latency time in the Morris water maze test. Evo reduced the deposition of amyloid beta 42 (Aβ42) in the brain, and increased the serum level of Aβ42, but showed no significant effects on Aβ40. In addition, six weeks of Evo administration significantly suppressed oxidative stress by modulating the related enzyme levels. In the central cholinergic system of AD mice, Evo significantly increased the serum levels of acetylcholine and choline acetyltransferase and decreased the level of acetylcholinesterase in the serum, hypothalamus, and brain. Our results provide experimental evidence that Evo can serve as a neuroprotective candidate for the prevention and/or treatment of neurodegenerative diseases.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Apoptose/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Quinazolinas/uso terapêutico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular , Camundongos , Camundongos Endogâmicos BALB C , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/metabolismo , Quinazolinas/farmacologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
For the purpose of improving the tumor delivery of doxorubicin (DOX), a kind of peptide-DOXO conjugate was designed and prepared, in which the peptide composed of an albumin-binding domain (ABD) and a tumor-specific internalizing sequence (RGDK or RPARPAR) was conjugated to a (6-maleimidocaproyl) hydrazone derivative of doxorubicin (DOXO-EMCH). The doxorubicin uptake by lung cancer cell line of A549 evidenced that the conjugates are capable of being internalized through a tumor-specific sequence mediated manner, and the intracellular imaging of distribution in A549 cell demonstrated that the conjugated doxorubicin can be delivered to the cell nucleus. The A549 cell cytotoxicity of peptide-DOXO conjugates was presented with IC50 values and shown in the range of about 9-11 µM. Pharmacokinetics study revealed that both conjugates exhibited nearly 5.5 times longer half-time than DOX, and about 4 times than DOXO-EMCH. The in vivo growth inhibitions of the two peptide-DOXO conjugates on BALB/c nude mice bearing A549 tumor (47.78% for ABD-RGDK-DOXO and 47.09% for ABD-RPARPAR-DOXO) were much stronger than that of doxorubicin and DOXO-EMCH (24.28% and 25.67% respectively) at a doxorubicin equivalent dose. Besides, the in vivo fluorescence imaging study confirmed that the peptide markedly increased the payload accumulation in tumor tissues and indicated that albumin binding domain fusing tumor-specific sequence effectively enhanced the tumor delivery of doxorubicin and thus improved its therapeutic potency.
Assuntos
Antibióticos Antineoplásicos/metabolismo , Doxorrubicina/análogos & derivados , Doxorrubicina/metabolismo , Hidrazonas/metabolismo , Peptídeos/química , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos NusRESUMO
The purpose of this study was to examine the effects of 18ß-glycyrrhetinic acid (GA), a novel naturally derived agent, in suppressing prolactin (PRL) hyperactivity and reducing antipsychotic-induced hyperprolactinemia (hyperPRL) and the underlying mechanisms in in vitro and in vivo models. GA treatment for 24 h inhibited PRL synthesis and secretion in MMQ cells and cultured pituitary cells in a dose-dependent fashion; but this effect was not reproduced in GH3 cells that lack the expression of functional dopamine D2 receptors. GA suppressed elevated PRL level and growth hormone, and normalized several sex hormones in a rat model of hyperPRL, produced by repeated injection of the dopamine blocker metoclopramide. GA also modulated the expression 5-HT1A and 5-HT2A receptors in both in vivo and in vitro models. These results indicate that GA is effective in suppressing PRL hyperactivity caused by the blockade of dopamine D2 receptors. This suppressive effect of GA may be related to its modulation of the serotonergic system. This study provides additional evidence in support of GA as an adjunct for the treatment of hyperPRL.
Assuntos
Antipsicóticos/farmacologia , Ácido Glicirretínico/análogos & derivados , Hiperprolactinemia/tratamento farmacológico , Prolactina/metabolismo , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Ácido Glicirretínico/farmacologia , Hiperprolactinemia/induzido quimicamente , Ratos , Receptores de Dopamina D2/metabolismoRESUMO
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 FioRESUMO
Alzheimer's disease (AD) is a common neurodegenerative disorder. Polysaccharides have been scientifically demonstrated to possess neuroprotective properties. In this study, a polysaccharide was isolated from the fruiting bodies of Hericium coralloides using hot water extraction and purified using column chromatography. This H. coralloides polysaccharide (HCP) is a galactan with a main chain of â6)-α-d-Galp-(1 â and a molecular weight of 16.06 kDa. The partial α-l-Fucp-(1 â substitution takes place at its O-2 position. The neuroprotective effects of HCP were investigated in an APP/PS1 mouse model of Alzheimer's disease. The step-down and Morris water maze tests demonstrated that HCP effectively ameliorated cognitive impairment. After 8-week treatment, HCP reduced amyloid-ß plaques and phosphorylated tau protein deposition. In combination with the gut microbiota and metabolites, proteomic analysis suggested that the neuroprotective effects of HCP are associated with neuroinflammation and autophagy. Immunofluorescence and western blotting analyses confirmed that HCP facilitated the polarization of M2 microglia by augmenting autophagy flux, thereby effectively reducing levels of amyloid-ß plaques and neuroinflammation. These data demonstrate that HCP effectively mitigates neuroinflammation by enhancing autophagic flux, demonstrating its potential for the treatment of AD.
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.