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1.
Plant Cell Environ ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757448

RESUMO

Global climate change is affecting plant photosynthesis and transpiration processes, as well as increasing weather extremes impacting socio-political and environmental events and decisions for decades to come. One major research challenge in plant biology and ecology is the interaction of photosynthesis with the environment. Stomata control plant gas exchange and their evolution was a crucial innovation that facilitated the earliest land plants to colonize terrestrial environments. Stomata couple homoiohydry, together with cuticles, intercellular gas space, with the endohydric water-conducting system, enabling plants to adapt and diversify across the planet. Plants control stomatal movement in response to environmental change through regulating guard cell turgor mediated by membrane transporters and signaling transduction. However, the origin, evolution, and active control of stomata remain controversial topics. We first review stomatal evolution and diversity, providing fossil and phylogenetic evidence of their origins. We summarize functional evolution of guard cell membrane transporters in the context of climate changes and environmental stresses. Our analyses show that the core signaling elements of stomatal movement are more ancient than stomata, while genes involved in stomatal development co-evolved de novo with the earliest stomata. These results suggest that novel stomatal development-specific genes were acquired during plant evolution, whereas genes regulating stomatal movement, especially cell signaling pathways, were inherited ancestrally and co-opted by dynamic functional differentiation. These two processes reflect the different adaptation strategies during land plant evolution.

2.
J Exp Bot ; 75(3): 935-946, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37904595

RESUMO

Tea (Camellia sinensis) is a highly important beverage crop renowned for its unique flavour and health benefits. Chlorotic mutants of tea, known worldwide for their umami taste and economic value, have gained global popularity. However, the genetic basis of this chlorosis trait remains unclear. In this study, we identified a major-effect quantitative trait locus (QTL), qChl-3, responsible for the chlorosis trait in tea leaves, linked to a non-synonymous polymorphism (G1199A) in the magnesium chelatase I subunit (CsCHLI). Homozygous CsCHLIA plants exhibited an albino phenotype due to defects in magnesium protoporphyrin IX and chlorophylls in the leaves. Biochemical assays revealed that CsCHLI mutations did not affect subcellular localization or interactions with CsCHLIG and CsCHLD. However, combining CsCHLIA with CsCHLIG significantly reduced ATPase activity. RNA-seq analysis tentatively indicated that CsCHLI inhibited photosynthesis and enhanced photoinhibition, which in turn promoted protein degradation and increased the amino acid levels in chlorotic leaves. RT-qPCR and enzyme activity assays confirmed the crucial role of asparagine synthetase and arginase in asparagine and arginine accumulation, with levels increasing over 90-fold in chlorotic leaves. Therefore, this study provides insights into the genetic mechanism underlying tea chlorosis and the relationship between chlorophyll biosynthesis and amino acid metabolism.


Assuntos
Anemia Hipocrômica , Camellia sinensis , Liases , Camellia sinensis/genética , Camellia sinensis/metabolismo , Clorofila/metabolismo , Chá/metabolismo , Aminoácidos/metabolismo , Mutação , Anemia Hipocrômica/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38763958

RESUMO

A minority of children born small for gestational age (SGA) may experience catch-up growth failure and remain short in adulthood. However, the underlying causes and mechanisms of this phenomenon are not yet fully comprehended. We reviewed the present state of research concerning the growth hormone-insulin-like growth factor axis and growth plate in SGA children who fail to achieve catch-up growth. Additionally, we explored the factors influencing catch-up growth in SGA children and potential molecular mechanisms involved. Furthermore, we considered the potential benefits of supplementary nutrition, specific dietary patterns, probiotics and drug therapy in facilitating catch-up growth.

4.
Arterioscler Thromb Vasc Biol ; 43(2): 253-266, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36519467

RESUMO

BACKGROUND: Inappropriate activation and aggregation of platelets can lead to arterial thrombosis. Thrombin is the most potent platelet agonist that activates human platelets via two PARs (proteinase-activated receptors), PAR1 and PAR4. The aim is to study the activity and mechanism of an oligosaccharide HS-11 (the undecasaccharide, derived from sea cucumber Holothuria fuscopunctata) in inhibiting thrombin-mediated platelet activation and aggregation and to evaluate its antithrombotic activity. METHODS: Platelet activation was analyzed by detecting CD62P/P-selectin expression using flow cytometry. The HS-11-thrombin interaction and the binding site were studied by biolayer interferometry. Intracellular Ca2+ mobilization of platelets was measured by FLIPR Tetra System using Fluo-4 AM (Fluo-4 acetoxymethyl). Platelet aggregation, thrombus formation, and bleeding Assay were assessed. RESULTS: An oligosaccharide HS-11, depolymerized from fucosylated glycosaminoglycan from sea cucumber Holothuria fuscopunctata blocks the interaction of thrombin with PAR1 and PAR4 complex by directly binding to thrombin exosite II, and completely inhibits platelet signal transduction, including intracellular Ca2+ mobilization and protein phosphorylation. Furthermore, HS-11 potently inhibits thrombin-PARs-mediated platelet aggregation and reduces thrombus formation in a model of ex vivo thrombosis. CONCLUSIONS: The study firstly report that the fucosylated glycosaminoglycan oligosaccharide has antiplatelet activity by binding to thrombin exosite II, and demonstrates that thrombin exosite II plays an important role in the simultaneous activation of PAR1 and PAR4, which may be a potential antithrombotic target for effective treatment of arterial thrombosis.


Assuntos
Receptor PAR-1 , Trombose , Humanos , Plaquetas/metabolismo , Fibrinolíticos/farmacologia , Glicosaminoglicanos/metabolismo , Oligossacarídeos/farmacologia , Ativação Plaquetária , Agregação Plaquetária , Receptores de Trombina , Trombina/metabolismo , Trombose/prevenção & controle , Trombose/metabolismo
5.
Eur J Pediatr ; 183(5): 2257-2272, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38411716

RESUMO

Patients with Aarskog-Scott syndrome (AAS) have short stature, facial anomalies, skeletal deformities, and genitourinary malformations. FYVE, RhoGEF, and PH domain-containing 1 (FGD1) is the only known causative gene of AAS. However, the diagnosis of AAS remains difficult, and specific treatments are still absent. Patients suspected with AAS were recruited, and clinical information was collected. Genetic testing and functional analysis were carried out for the diagnosis. By literature review, we summarized the clinical and genetic characteristics of FGD1-related AAS and analyzed the genotype-phenotype correlation. Five patients were recruited, and four novel FGD1 variants were identified. The diagnosis of AAS was confirmed by genetic analysis and functional study. Three patients treated with growth hormone showed improved heights during the follow-up period. By literature review, clinical features of AAS patients with FGD1 variants were summarized. Regarding FGD1 variations, substitutions were the most common form, and among them, missense variants were the most frequent. Moreover, we found patients with drastic variants showed higher incidences of foot and genitourinary malformations. Missense variants in DH domain were related to a lower incidence of cryptorchidism.   Conclusion: We reported four novel pathogenic FGD1 variations in AAS patients and confirmed the efficacy and safety of growth hormone treatment in FGD1-related AAS patients with growth hormone deficiency. Additionally, our literature review suggested the crucial role of DH domain in FGD1 function. What is Known: • Aarskog-Scott syndrome is a rare genetic disease, and the only known cause is the variant in FGD1 gene. The typical clinical manifestations of AAS include facial, skeletal, and urogenital deformities and short stature. What is New: • We reported four novel FGD1 variants and reported the treatment of growth hormone in FGD1-related AAS patients. Our genotype-phenotype correlation analysis suggested the crucial role of DH domain in FGD1 function.


Assuntos
Anormalidades Múltiplas , Face , Doenças Genéticas Ligadas ao Cromossomo X , Genitália Masculina , Fatores de Troca do Nucleotídeo Guanina , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico , Nanismo/genética , Nanismo/diagnóstico , Nanismo/tratamento farmacológico , Face/anormalidades , Estudos de Associação Genética , Genitália Masculina/anormalidades , Fatores de Troca do Nucleotídeo Guanina/genética , Deformidades Congênitas da Mão/genética , Deformidades Congênitas da Mão/diagnóstico , Cardiopatias Congênitas/genética , Cardiopatias Congênitas/diagnóstico , Fenótipo , Dermatoses do Couro Cabeludo/genética , Dermatoses do Couro Cabeludo/diagnóstico , Dermatoses do Couro Cabeludo/tratamento farmacológico , Dermatoses do Couro Cabeludo/congênito , Anormalidades Urogenitais/genética , Anormalidades Urogenitais/diagnóstico
6.
Plant Biotechnol J ; 21(6): 1191-1205, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36786225

RESUMO

In contrast to CUT&Tag approaches for profiling bulk histone modifications, current CUT&Tag methods for analysing specific transcription factor (TF)-DNA interactions remain technically challenging due to TFs having relatively low abundance. Moreover, an efficient CUT&Tag strategy for plant TFs is not yet available. Here, we first applied biotinylated Tn5 transposase-mediated CUT&Tag (B-CUT&Tag) to produce high-quality libraries for interrogating TF-DNA interactions. B-CUT&Tag combines streptavidin-biotin-based DNA purification with routine CUT&Tag, optimizing the removal of large amounts of intact chromatin not targeted by specific TFs. The biotinylated chromatin fragments are then purified for construction of deep sequencing libraries or qPCR analysis. We applied B-CUT&Tag to probe genome-wide DNA targets of Squamosa promoter-binding-like protein 9 (SPL9), a well-established TF in Arabidopsis; the resulting profiles were efficient and consistent in demonstrating its well-established target genes in juvenile-adult transition/flowering, trichome development, flavonoid biosynthesis, wax synthesis and branching. Interestingly, our results indicate functions of AtSPL9 in modulating growth-defence trade-offs. In addition, we established a method for applying qPCR after CUT&Tag (B-CUT&Tag-qPCR) and successfully validated the binding of SPL9 in Arabidopsis and PHR2 in rice. Our study thus provides a convenient and highly efficient CUT&Tag strategy for profiling TF-chromatin interactions that is widely applicable to the annotation of cis-regulatory elements for crop improvement.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , DNA/genética , DNA/metabolismo , Cromatina/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
7.
J Exp Bot ; 74(6): 1806-1820, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36585802

RESUMO

Strand-specific RNA-seq is a powerful tool for the discovery of novel transcripts, annotation of genomes, and profiling of gene expression levels. Tn5 transposase has been successfully applied in massive-scale sequencing projects; in particular, Tn5 adaptor modification is used in epigenetics, genomic structure, and chromatin visualization. We developed a novel dU-adaptor-assembled Tn5-mediated strand-specific RNA-sequencing protocol and compared this method with the leading dUTP method in terms of experimental procedure and multiple quality metrics of the generated libraries. The results showed that the dU-Tn5 method is easy to operate and generates a strand-specific RNA-seq library of comparable quality considering library complexity, strand-specificity, evenness, and continuity of annotated transcript coverage. We also evaluated the performance of the dU-Tn5 method in identifying nitrogen-responsive protein-coding genes and long non-coding RNAs in soybean roots. The results indicated that ~62-70% of differentially expressed genes detected from conventional libraries were also detected in dU-Tn5 libraries, indicating good agreement of our method with the current standard; moreover, their fold-changes were highly correlated (R>0.9). Thus, our method provides a promising 'do-it-yourself' stranded RNA-seq procedure for gene expression profiling.


Assuntos
Cromatina , Perfilação da Expressão Gênica , Biblioteca Gênica , DNA Complementar/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA
8.
Osteoporos Int ; 34(4): 641-658, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36527476

RESUMO

Sequential treatment of osteoporosis has been increasingly mentioned in recent years. However, the corresponding systematic review has not been reported. This study aims to systematically review and assess all full-text pharmacoeconomic studies of sequential treatment for osteoporosis. A comprehensive literature search was performed using PubMed, EMBASE (Ovid), CNKI, and Wanfang Database to identify original articles, published before June 17, 2022. The quality of included articles was evaluated by the updated Consolidated Health Economic Evaluation Reporting Standards (CHEERS 2022) and the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases International Osteoporosis Foundation (ESCEO-IOF). In general, ten articles were included in this review. For the comparison between sequential treatment and bisphosphonate monotherapy, more than 75% of studies demonstrated the sequential treatment was cost-effective or dominant, with the exception of sequential treatment involving teriparatide. When the comparisons occurred between the two sequential treatment groups, the sequential treatments associated with either abaloparatide or romosozumab were cost-effective or dominant compared to the sequential treatment involving teriparatide. Several major key drivers of cost-effectiveness included drug cost, medication persistence and adherence, drug effect on fracture risk, offset effect, time horizon, and baseline fracture risk. The most of studies were identified as high quality in CHEERS (2022) and ESCEO-IOF. The cost-effectiveness of sequential treatment for osteoporosis is influenced by multiple factors. Generally, the sequential treatments involving abaloparatide, romosozumab, denosumab, and bisphosphonates may be considered as the preferred option for osteoporosis with high fracture risk, while the sequential treatment with teriparatide was not a cost-effectiveness strategy. The ESCEO-IOF and CHEER (2022) increase the transparency, comparability, extrapolation, and quality of research, engage patients and the general public in research on health services and policies, and help improve the quality of health technology assessment.


Assuntos
Conservadores da Densidade Óssea , Fraturas Ósseas , Doenças Musculoesqueléticas , Osteoporose , Humanos , Análise Custo-Benefício , Osteoporose/tratamento farmacológico , Fraturas Ósseas/tratamento farmacológico , Teriparatida/uso terapêutico , Difosfonatos/uso terapêutico
9.
Int J Mol Sci ; 24(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36982636

RESUMO

Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides (nt) that are not translated into known functional proteins. This broad definition covers a large collection of transcripts with diverse genomic origins, biogenesis, and modes of action. Thus, it is very important to choose appropriate research methodologies when investigating lncRNAs with biological significance. Multiple reviews to date have summarized the mechanisms of lncRNA biogenesis, their localization, their functions in gene regulation at multiple levels, and also their potential applications. However, little has been reviewed on the leading strategies for lncRNA research. Here, we generalize a basic and systemic mind map for lncRNA research and discuss the mechanisms and the application scenarios of 'up-to-date' techniques as applied to molecular function studies of lncRNAs. Taking advantage of documented lncRNA research paradigms as examples, we aim to provide an overview of the developing techniques for elucidating lncRNA interactions with genomic DNA, proteins, and other RNAs. In the end, we propose the future direction and potential technological challenges of lncRNA studies, focusing on techniques and applications.


Assuntos
RNA Longo não Codificante , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação da Expressão Gênica , Genoma
10.
Mar Drugs ; 20(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36286476

RESUMO

Fucosylated chondroitin sulfate (FCS) from the sea cucumber Acaudina molpadioides (FCSAm) is the first one that was reported to be branched by disaccharide GalNAc-(α1,2)-Fuc3S4S (15%) and sulfated Fuc (85%). Here, four size-homogenous fractions, and seven oligosaccharides, were separated from its ß-eliminative depolymerized products. Detailed NMR spectroscopic and MS analyses revealed the oligomers as hexa-, hepta-, octa-, and nonasaccharide, which further confirmed the precise structure of native FCSAm: it was composed of the CS-E-like backbone with a full content of sulfation at O-4 and O-6 of GalNAc in the disaccharide repeating unit, and the branches consisting of sulfated fucose (Fuc4S and Fuc2S4S) and heterodisaccharide [GalNAc-(α1,2)-Fuc3S4S]. Pharmacologically, FCSAm and its depolymerized derivatives, including fractions and oligosaccharides, showed potent neurite outgrowth-promoting activity in a chain length-dependent manner. A comparison of analyses among oligosaccharides revealed that the sulfate pattern of the Fuc branches, instead of the heterodisaccharide, could affect the promotion intensity. Fuc2S4S and the saccharide length endowed the neurite outgrowth stimulation activity most.


Assuntos
Pepinos-do-Mar , Animais , Pepinos-do-Mar/química , Sulfatos de Condroitina/farmacologia , Sulfatos de Condroitina/química , Fucose/química , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Dissacarídeos , Crescimento Neuronal , Sulfatos/química
11.
Gen Physiol Biophys ; 41(6): 535-547, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36454114

RESUMO

This study clarified the effect of homocysteine on adventitial fibroblasts (AFs) and its relationship with angiotensin II type 1 receptor (AT1R). Hyperhomocysteinemia aggravated the plaque area and increased the expression of IL-6, MCP-1, and macrophage infiltration in the plaque and adventitia of the aorta, whereas telmisartan improved this effect. Hyperhomocysteinemia induced the occurrence of the AFs marker protein ER-TR7 in the plaque and entire layer of the aorta, whereas telmisartan improved these effects, indicating that homocysteine induced AFs migration and that AT1R mediated this process. The migration experiments of AFs also reached the same conclusion. Homocysteine increased the phosphorylation levels of PKC and ERK1/2 in the AFs and HEK293A cells transfected with the AT1R plasmid, whereas telmisartan inhibited this effect, indicating that homocysteine activated AT1R intracellular signaling pathway. Homocysteine also increased the AFs At1R expression. Conclusion, homocysteine promoted adventitial inflammation, induced AFs migration, and aggravated atherosclerosis by activating AT1R.


Assuntos
Aterosclerose , Hiper-Homocisteinemia , Humanos , Túnica Adventícia , Homocisteína , Receptor Tipo 1 de Angiotensina , Telmisartan , Fibroblastos
12.
World J Microbiol Biotechnol ; 39(1): 15, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36401137

RESUMO

Bacterial outer membrane proteins (Omps) are essential for environmental sensing, stress responses, and substance transport. Our previous study discovered that OmpA contributes to planktonic growth, biocide resistance, biofilm formation, and swimming motility in Citrobacter werkmanii, whereas the molecular functions of OmpF in this strain are largely unknown. Thus, in this study, the ompF gene was firstly knocked out from the genome of C. werkmanii using a homologous recombination method, and its phenotypical alternations of ∆ompF were then thoroughly characterized using biochemical and molecular approaches with the parental wild type (WT) and complementary (∆ompF-com) strains. The results demonstrated that the swimming ability of ∆ompF on semi-solid plates was reduced compared to WT due to the down-regulation of flgC, flgH, fliK, and fliF. Meanwhile, ompF deletion reduces biofilm formation on both glass and polystyrene surfaces due to decreased cell aggregation. Furthermore, ompF inactivation induced different osmotic stress (carbon sources and metal ions) responses in its biofilms when compared to WT and ∆ompF-com. Finally, a total of 6 maltose metabolic genes of lamB, malE, malK, malG, malM, and malF were all up-regulated in ∆ompF. The gene knockout and HPLC results revealed that the MalEFGK2 cluster was primarily responsible for maltose transport in C. werkmanii. Furthermore, we discovered for the first time that the upstream promoter of OmpF and its transcription can be combined with and negatively regulated by MalT. Overall, OmpF plays a role in a variety of biochemical processes and molecular functions in C. werkmanii, and it may even act as a targeted site to inhibit biofilm formation.


Assuntos
Maltose , Natação , Osmorregulação , Proteínas da Membrana Bacteriana Externa/genética , Biofilmes
13.
Environ Dev Sustain ; : 1-25, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-35846738

RESUMO

The establishment of the green belt and road is an inevitable choice to conform to and lead the green and low-carbon cycle development and an inherent requirement for sustainable development. Therefore, we establish an evaluation system of green development oriented to carbon neutrality, and calculate the green development level (GDL) of the provinces along the belt and road in China from 2003 to 2018 by using a three-dimensional evaluation model. In addition, this paper employs the Obstacle Degree Model to identify the main obstacle factors that affect GDL, and provides targeted and differentiated countermeasures and suggestions for improving the regional GDL. Our results suggested that the overall GDL has improved, but not obvious, with a low level. The GDL and coordination degree between different regions exist certain differences, and its spatial pattern is characterized by "high in southeast and northeast, low in southwest and northwest". From a regional perspective, innovation capacity is the key factor that affects the green development of the region in southeast, northeast, northwest and southwest China. Driving economic green transformation and promoting industrial energy conservation and emission reduction through technological innovation are the internal driving forces to achieve regional green sustainable development.

14.
Appl Microbiol Biotechnol ; 105(7): 2841-2854, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33763710

RESUMO

The genus Citrobacter is commonly found in environmental and industrial settings, some members of which have been used for bioremediation of heavy metals owing to the absorption ability of their biofilms. Although our previous studies have found that the outer membrane protein A (OmpA) contributes to the process of Citrobacter werkmanii biofilm formation, the underlying mechanisms remain elusive. Therefore, we deleted ompA from the genome of C. werkmanii and investigated its phenotypes in comparison to the wild type strain (WT) and the complementary strain using biochemical and molecular techniques including RNA-Seq. Our results demonstrated that the deletion of ompA led to an increase in biofilm formation on both polystyrene and glass surfaces due to upregulation of some biofilm formation related genes. Meanwhile, swimming ability, which is mediated by activation of flagellar assembly genes, was increased on semi-solid plates in the ∆ompA strain when compared with WT. Additionally, inactivation of ompA also caused increased 1,2-benzisothiazolin-3-one (BIT) resistance, differential responses to Ca2+ stress, curli protein expression and cellulose production. Finally, ∆ompA caused differential expression of a total of 1470 genes when compared with WT, of which 146 were upregulated and 1324 were downregulated. These genes were classified into different Gene Ontology (GO) and KEGG pathways. In summary, ompA in C. werkmanii contributes to a variety of biological functions and may act as a target site to modulate biofilm formation. KEY POINTS: • ompA is a negative regulator for biofilm formation by C. werkmanii. • ompA inhibits swimming motility of C. werkmanii. • ompA deletion causes different expression profiles in C. werkmanii.


Assuntos
Desinfetantes , Proteínas de Bactérias/genética , Biofilmes , Citrobacter/genética , Regulação Bacteriana da Expressão Gênica , Natação
15.
Platelets ; 32(7): 975-983, 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-32970503

RESUMO

Fucosylated glycosaminoglycan (FG) from sea cucumbers has been reported to have anticoagulant effects via targeting intrinsic tenase. However, FG from natural source also potentially poses risks due to its FXIIa activation and platelet aggregating effects. Here, we found that the effect of FG on human platelet aggregation depended on both the sulfation pattern and chain length. FGs with higher content of Fuc2S4S and larger molecular weight (≥14 kD) had stronger activity. Both platelet aggregation and P-selectin expression induced by TaFG (an FG from Thelenota ananas) were decreased as the molecular weight reduced. Ticagrelor, aspirin and wortmannin completely blocked the secretion (ADP) but only partially blocked the aggregation induced by TaFG. Tirofiban an αIIbß3 antagonist however potently inhibited both the secretion and aggregation, with IC50 of 6.01 ± 1.1.97 nM. Furthermore, TaFG could bind to human αIIbß3 with high affinity, and the affinities of two FGs were paralleled with their activity in platelet aggregation or activation. These results indicated that αIIbß3 played an important role in TaFG-induced platelet aggregation which was mediated by PI3K, and that platelet secretion was required for the amplification of aggregation.


Assuntos
Plaquetas/metabolismo , Glicosaminoglicanos/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Adulto , Feminino , Glicosaminoglicanos/farmacologia , Humanos , Masculino , Adulto Jovem
16.
Mar Drugs ; 19(4)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920475

RESUMO

dHG-5 (Mw 5.3 kD) is a depolymerized glycosaminoglycan from sea cucumber Holothuria fuscopunctata. As a selective inhibitor of intrinsic Xase (iXase), preclinical study showed it was a promising anticoagulant candidate without obvious bleeding risk. In this work, two bioanalytical methods based on the anti-iXase and activated partial thromboplastin time (APTT) prolongation activities were established and validated to determine dHG-5 concentrations in plasma and urine samples. After single subcutaneous administration of dHG-5 at 5, 9, and 16.2 mg/kg to rats, the time to peak concentration (Tmax) was at about 1 h, and the peak concentration (Cmax) was 2.70, 6.50, and 10.11 µg/mL, respectively. The plasma elimination half-life(T1/2ß) was also about 1 h and dHG-5 could be almost completely absorbed after s.c. administration. Additionally, the pharmacodynamics of dHG-5 was positively correlated with its pharmacokinetics, as determined by rat plasma APTT and anti-iXase method, respectively. dHG-5 was mainly excreted by urine as the unchanged parent drug and about 60% was excreted within 48 h. The results suggested that dHG-5 could be almost completely absorbed after subcutaneous injection and the pharmacokinetics of dHG-5 are predictable. Studying pharmacokinetics of dHG-5 could provide valuable information for future clinical studies.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Inibidores do Fator Xa/farmacocinética , Glicosaminoglicanos/farmacocinética , Holothuria/metabolismo , Animais , Biotransformação , Monitoramento de Medicamentos , Inibidores do Fator Xa/administração & dosagem , Inibidores do Fator Xa/isolamento & purificação , Glicosaminoglicanos/administração & dosagem , Glicosaminoglicanos/isolamento & purificação , Meia-Vida , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Tempo de Tromboplastina Parcial , Ratos Sprague-Dawley , Eliminação Renal
17.
Mar Drugs ; 19(9)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34564149

RESUMO

Fucosylated glycosaminoglycan (FG) from sea cucumber is a potent anticoagulant by inhibiting intrinsic coagulation tenase (iXase). However, high-molecular-weight FGs can activate platelets and plasma contact system, and induce hypotension in rats, which limits its application. Herein, we found that FG from T. ananas (TaFG) and FG from H. fuscopunctata (HfFG) at 4.0 mg/kg (i.v.) could cause significant cardiovascular and respiratory dysfunction in rats, even lethality, while their depolymerized products had no obvious side effects. After injection, native FG increased rat plasma kallikrein activity and levels of the vasoactive peptide bradykinin (BK), consistent with their contact activation activity, which was assumed to be the cause of hypotension in rats. However, the hemodynamic effects of native FG cannot be prevented by the BK receptor antagonist. Further study showed that native FG induced in vivo procoagulation, thrombocytopenia, and pulmonary embolism. Additionally, its lethal effect could be prevented by anticoagulant combined with antiplatelet drugs. In summary, the acute toxicity of native FG is mainly ascribed to pulmonary microvessel embolism due to platelet aggregation and contact activation-mediated coagulation, while depolymerized FG is a safe anticoagulant candidate by selectively targeting iXase.


Assuntos
Anticoagulantes/toxicidade , Glicosaminoglicanos/toxicidade , Animais , Anticoagulantes/química , Coagulação Sanguínea/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Fucose/química , Glicosaminoglicanos/química , Coração/efeitos dos fármacos , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Ativação Plaquetária/efeitos dos fármacos , Embolia Pulmonar/induzido quimicamente , Embolia Pulmonar/patologia , Ratos Sprague-Dawley , Respiração/efeitos dos fármacos , Pepinos-do-Mar , Função Ventricular Esquerda/efeitos dos fármacos
18.
Neural Plast ; 2021: 5560453, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194487

RESUMO

Objectives: Previous researches have demonstrated that abnormal functional connectivity (FC) is associated with the pathophysiology of bipolar disorder (BD). However, inconsistent results were obtained due to different selections of regions of interest in previous researches. This study is aimed at examining voxel-wise brain-wide functional connectivity (FC) alterations in the first-episode, drug-naive patient with BD in an unbiased way. Methods: A total of 35 patients with BD and 37 age-, sex-, and education-matched healthy controls underwent resting-state functional magnetic resonance imaging (rs-fMRI). Global-brain FC (GFC) was applied to analyze the image data. Support vector machine (SVM) was adopted to probe whether GFC abnormalities could be used to identify the patients from the controls. Results: Patients with BD exhibited increased GFC in the left inferior frontal gyrus (LIFG), pars triangularis and left precuneus (PCu)/superior occipital gyrus (SOG). The left PCu belongs to the default mode network (DMN). Furthermore, increased GFC in the LIFG, pars triangularis was positively correlated with the triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) and negatively correlated with the scores of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) coding test and Stroop color. Increased GFC values in the left PCu/SOG can be applied to discriminate patients from controls with preferable sensitivity (80.00%), specificity (75.68%), and accuracy (77.78%). Conclusions: This study found increased GFC in the brain regions of DMN; LIFG, pars triangularis; and LSOG, which was associated with dyslipidemia and cognitive impairment in patients with BD. Moreover, increased GFC values in the left PCu/SOG may be utilized as a potential biomarker to differentiate patients with BD from controls.


Assuntos
Transtorno Bipolar/epidemiologia , Transtornos Cognitivos/epidemiologia , Conectoma , Dislipidemias/epidemiologia , Adolescente , Adulto , Transtorno Bipolar/sangue , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/psicologia , Comorbidade , Rede de Modo Padrão/fisiologia , Feminino , Humanos , Masculino , Neuroimagem , Lobo Parietal/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Máquina de Vetores de Suporte , Adulto Jovem
19.
J Exp Bot ; 71(22): 7118-7131, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-32915968

RESUMO

Barley possesses a branchless, spike-shaped inflorescence where determinate spikelets attach directly to the main axis, but the developmental mechanism of spikelet identity remains largely unknown. Here we report the functional analysis of the barley gene BRANCHED AND INDETERMINATE SPIKELET 1 (BDI1), which encodes a TCP transcription factor and plays a crucial role in determining barley inflorescence architecture and spikelet development. The bdi1 mutant exhibited indeterminate spikelet meristems that continued to grow and differentiate after producing a floret meristem; some spikelet meristems at the base of the spike formed two fully developed seeds or converted to branched spikelets, producing a branched inflorescence. Map-based cloning analysis showed that this mutant has a deletion of ~600 kb on chromosome 5H containing three putative genes. Expression analysis and virus-induced gene silencing confirmed that the causative gene, BDI1, encodes a CYC/TB1-type TCP transcription factor and is highly conserved in both wild and cultivated barley. Transcriptome and regulatory network analysis demonstrated that BDI1 may integrate regulation of gene transcription cell wall modification and known trehalose-6-phosphate homeostasis to control spikelet development. Together, our findings reveal that BDI1 represents a key regulator of inflorescence architecture and meristem determinacy in cereal crop plants.


Assuntos
Hordeum , Meristema , Regulação da Expressão Gênica de Plantas , Hordeum/genética , Hordeum/metabolismo , Meristema/genética , Meristema/metabolismo , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
J Exp Bot ; 71(18): 5389-5401, 2020 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-32497208

RESUMO

Grain size is a major determinant of grain yield in sorghum and other cereals. Over 100 quantitative trait loci (QTLs) of grain size have been identified in sorghum. However, no gene underlying any grain size QTL has been cloned. Here, we describe the fine mapping and cloning of one grain size QTL. From an F8 recombinant inbred line population derived from a cross between inbred lines 654 and LTR108, we identified 44 grain size QTLs. One QTL, qTGW1a, was detected consistently on the long arm of chromosome 1 in the span of 4 years. Using the extreme recombinants from an F2:3 fine-mapping population, qTGW1a was delimited within a ~33 kb region containing three predicted genes. One of them, SORBI_3001G341700, predicted to encode a G-protein γ subunit and homologous to GS3 in rice, is likely to be the causative gene for qTGW1a. qTGW1a appears to act as a negative regulator of grain size in sorghum. The functional allele of the putatively causative gene of qTGW1a from inbred line 654 decreased grain size, plant height, and grain yield in transgenic rice. Identification of the gene underlying qTGW1a advances our understanding of the regulatory mechanisms of grain size in sorghum and provides a target to manipulate grain size through genome editing.


Assuntos
Oryza , Sorghum , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Grão Comestível/genética , Oryza/genética , Fenótipo , Subunidades Proteicas , Sorghum/genética
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