RESUMO
Being the first line of defense, intestinal mucosal immunity serves as in maintaining immune homeostasis among organisms. This study investigated the impact of the areca inflorescence polysaccharide (AFP) on intestinal mucosal immunity and elucidated the mechanisms responsible for the immunomodulatory effects of AFP. The immunosuppression mouse model was established using the cyclophosphamide. The intestinal mucosal status was evaluated based on the intestinal integrity, chemical and mucosal immune barriers, and intestinal flora. According to the findings, AFP enhances intestinal integrity by up-regulating the expression of tight junction proteins and reinforcing the chemical barrier through increased mucin-2, ß-defensins, and SIgA expression and secretion. Furthermore, AFP restores the mucosal immune barrier by regulating immune cells within Peyer's patches and lamina propria. AFP also reverses the intestinal flora balance and regulates its metabolism. Additionally, AFP effectively modulates the immune response in the spleen and peripheral blood. Together, these results indicated that AFP repairs mucosal damage and restores mucosal immunity, thereby preserving the immune homeostasis of organisms.
RESUMO
Mycoplasma synoviae (MS) is an essential pathogenic mycoplasma in poultry worldwide, posing a serious threat to the poultry industry's health. Timely detection is imperative for early diagnosis, prevention, and control of MS infection. Current laboratory methods for MS detection are generally complicated, time-consuming, and require sophisticated equipment. Therefore, a simple and rapid method is urgently needed. This study developed a novel real-time fluorescence-based recombinase-aided amplification (RF-RAA) technique for detecting MS nucleic acids, enabling target gene amplification within 20 min at 39°C. The RF-RAA outcomes are interpretable in 2 modalities: real-time fluorescence monitoring employing a temperature-controlled fluorescence detector or direct visual inspection facilitated by a portable blue light transilluminator. This method exhibits robust specificity, demonstrating no cross-reactivity with various common poultry pathogens, and achieves high sensitivity, detecting as low as 10 copies/µL for the standard plasmid. Seventy-one clinical samples of chicken throat swabs were detected by RF-RAA and real-time fluorescence quantitative polymerase chain reaction (qPCR) methods. The diagnostic coincidence rates of qPCR with RF-RAA (fluorescence monitoring) and RF-RAA (visual observation) were determined to be 100% and 97.2% (69/71), respectively. In conclusion, the RF-RAA method developed in this study provides a rapid and visually observable approach for MS detection, offering a novel technique to diagnosing MS infection, especially in resource-limited settings.
Assuntos
Galinhas , Infecções por Mycoplasma , Mycoplasma synoviae , Técnicas de Amplificação de Ácido Nucleico , Doenças das Aves Domésticas , Recombinases , Mycoplasma synoviae/isolamento & purificação , Mycoplasma synoviae/genética , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/microbiologia , Animais , Infecções por Mycoplasma/veterinária , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/microbiologia , Recombinases/metabolismo , Técnicas de Amplificação de Ácido Nucleico/veterinária , Técnicas de Amplificação de Ácido Nucleico/métodos , Fluorescência , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e EspecificidadeRESUMO
The symbiotic relationship between corals and their associated microorganisms is crucial for the health of coral reef eco-environmental systems. Recently, there has been a growing interest in unraveling how the manipulation of symbiont nutrient cycling affects the stress tolerance in the holobiont of coral reefs. However, most studies have primarily focused on coral-Symbiodiniaceae-bacterial interactions as a whole, neglecting the interactions between Symbiodiniaceae and bacteria, which remain largely unexplored. In this study, we proposed a hypothesis that there exists an inner symbiotic loop of Symbiodiniaceae and bacteria within the coral symbiotic loop. We conducted experiments to demonstrate how metabolic exchanges between Symbiodiniaceae and bacteria facilitate the nutritional supply necessary for cellular growth. It was seen that the beneficial bacterium, Ruegeria sp., supplied a nitrogen source to the Symbiodiniaceae strain Durusdinium sp., allowing this dinoflagellate to thrive in a nitrogen-free medium. The Ruegeria sp.-Durusdinium sp. interaction was confirmed through 15N-stable isotope probing-single cell Raman spectroscopy, in which 15N infiltrated into the bacterial cells for intracellular metabolism, and eventually the labeled nitrogen source was traced within the macromolecules of Symbiodiniaceae cells. The investigation into Symbiodiniaceae loop interactions validates our hypothesis and contributes to a comprehensive understanding of the intricate coral holobiont. These findings have the potential to enhance the health of coral reefs in the face of global climate change.
RESUMO
Understanding the evolutionary and ecological processes involved in population differentiation and speciation provides critical insights into biodiversity formation. In this study, we employed 29,865 single nucleotide polymorphisms (SNPs) and complete plastomes to examine genomic divergence and hybridization in Gentiana aristata, which is endemic to the Qinghai-Tibet Plateau (QTP) region. Genetic clustering revealed that G. aristata is characterized by geographic genetic structures with five clusters (West, East, Central, South and North). The West cluster has a specific morphological character (i.e., blue corolla) and higher values of FST compared to the remaining clusters, likely the result of the geological barrier formed by the Yangtze River. The West cluster diverged from the other clusters in the Early Pliocene; these remaining clusters diverged from one another in the Early Quaternary. Phylogenetic reconstructions based on SNPs and plastid data revealed substantial cyto-nuclear conflicts. Genetic clustering and D-statistics demonstrated rampant hybridization between the Central and North clusters, along the Bayankala Mountains, which form the geological barrier between the Central and North clusters. Species distribution modeling demonstrated the range of G. aristata expanded since the Last Interglacial period. Our findings provide genetic and morphological evidence of cryptic diversity in G. aristata, and identified rampant hybridization between genetic clusters along a geological barrier. These findings suggest that geological barriers and climatic fluctuations have an important role in triggering diversification as well as hybridization, indicating that cryptic diversity and hybridization are essential factors in biodiversity formation within the QTP region.
RESUMO
Chlorella has been applied in the production of selenium (Se) enriched organic biomass. However, limited information exists regarding heterotrophic selenium tolerance and its incorporation into Chlorella. This study aimed to investigate the potential of using Chlorella vulgaris K-01 for selenium biotransformation. To assess the dose-response effect of Se stress on the strain, time-series growth curves were recorded, growth productivity parameters were calculated, and Gaussian process (GP) regression analysis was performed. The strain's carbon and energy metabolism were evaluated by measuring residual glucose in the medium. Characterization of different forms of intracellular Se and residual Se in the medium was conducted using inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometer (ICP-OES). The EC50 value for the strain in response to Se stress was 38.08 mg/L. The maximum biomass productivity was 0.26 g/L/d. GP regression analysis revealed that low-level Se treatment could increase the biomass accumulation and the carrying capacity of Chlorella vulgaris K-01 in a heterotrophic culture. The maximum organic Se in biomass was 154.00 µg/g DW. These findings lay the groundwork for understanding heterotrophic microalgal production of Se-containing nutraceuticals, offering valuable insights into Se tolerance, growth dynamics, and metabolic responses in Chlorella vulgaris K-01.
RESUMO
Globally cultivated cereals are frequently threatened by various plant pathogenic agents such as Fusarium fungi. To combat these pathogens, researchers have made nanoparticles as potential agricultural pesticides. In this study, selenium and titanium dioxide NPs were synthesized using Trichoderma harzianum metabolites. Characterization of the NPs indicated varying size and shapes of both NPs and functional groups existence to constitute both NPs. The evaluation of antifungal activity of NPs against plant pathogenic fungi, Fusarium culmorum, indicated both NPs maximum antifungal activity at concentration of 100 mg/L. The impacts of nanoparticles on some beneficial plant growth promoting bacteria (PGPB) were evaluated and showed their inhibition effect on optical density of PGPB at a concentration of 100 mg/L but they did not have any impact on nitrogen fixation by bacteria. Existence of TiO2NPs reduced the intensity of color change to pink compared to the control indicating auxin production. Both NPs demonstrated different impact on phosphate solubilization index. This study suggests that the synthesized nanoparticles have the potential to serve as antifungal compounds at special concentration against plant diseases without significantly reducing the potential of PGPB at low concentrations.
Assuntos
Hypocreales , Nanopartículas , Trichoderma , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Desenvolvimento Vegetal , Trichoderma/metabolismoRESUMO
The elucidation of the immunomodulatory molecular mechanisms of polysaccharides has contributed to their further development and application. In this study, the effect of Areca inflorescence polysaccharide (AFP2a) on macrophage activation was confirmed and the detailed mechanisms were investigated based on a comprehensive transcriptional study and specific inhibitors. The results showed that AFP2a induced macrophage activation (M1 polarization), promoting macrophage proliferation, reactive oxygen species production, nitric oxide and cytokine release, and costimulatory molecule expression. RNA-seq analysis identified 5919 differentially expressed genes (DEGs). For DEGs, GO, KEGG, and Reactome enrichment analyses and PPI networks were conducted, elucidating that AFP2a activated macrophages mainly by triggering the Toll-like receptor cascade and corresponding adapter proteins (TIRAP and TRIF), thereby resulting in downstream NF-κB, TNF, and JAK-STAT signaling pathway expression. The inhibition assay revealed that TLR4 and TLR2 were essential for the recognition of AFP2a. This work provides an in-depth understanding of the immunoregulatory mechanism of AFP2a while offering a molecular basis for AFP2a to serve as a potential natural immunomodulator.
Assuntos
Areca , Inflorescência , Inflorescência/metabolismo , Macrófagos , NF-kappa B/metabolismo , Polissacarídeos/farmacologia , Polissacarídeos/metabolismo , RNA-Seq , Ativação de MacrófagosRESUMO
BACKGROUND: Tyrosinase, a copper-containing metalloenzyme with catalytic activity, is widely found in mammals. It is the key rate-limiting enzyme that catalyzes melanin synthesis. For humans, tyrosinase is beneficial to the darkening of eyes and hair. However, excessive deposition of melanin in the skin can lead to dull skin color and lead to pigmentation. Therefore, many skin-whitening compounds have been developed to decrease tyrosinase activity. This study aimed to identify a new tyrosinase inhibitory peptide through enzymatic hydrolysis, in vitro activity verification, molecular docking, and molecular dynamics (MD) simulation. RESULTS: A tripeptide Asp-Glu-Arg (DER) was identified, with a '-CDOCKER_Energy' value of 121.26 Kcal mol-1 . DER has effective tyrosinase inhibitory activity. Research shows that its half maximal inhibitory concentration value is 1.04 ± 0.01 mmol L-1 . In addition, DER binds to tyrosinase residues His85, His244, His259, and Asn260, which are key residues that drive the interaction between the peptide and tyrosinase. Finally, through MD simulation, the conformational changes and structural stability of the complexes were further explored to verify and supplement the results of molecular docking. CONCLUSION: This experiment shows that DER can effectively inhibit tyrosinase activity. His244, His259, His260, and Asn260 are the critical residues that drive the interaction between the peptide and tyrosinase, and hydrogen bonding is an important force. DER from Spirulina has the potential to develop functional products with tyrosinase inhibition. © 2024 Society of Chemical Industry.
Assuntos
Monofenol Mono-Oxigenase , Ficocianina , Spirulina , Humanos , Animais , Simulação de Acoplamento Molecular , Spirulina/metabolismo , Melaninas/metabolismo , Inibidores Enzimáticos/química , Peptídeos , Mamíferos/metabolismoRESUMO
Functionalization of GO with an amphiphilic block copolymer is designed with an aim to enhance its biocompatibility, however, long copolymer chains can screen the blade effect of GO to sacrifice its antimicrobial activities. To solve this problem, low molecular weight of poly(ethylene glycol) (PEG), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and their block copolymer were respectively introduced onto GO via an isophorone diisocyanate modified GO as a intermediate, followed by a solvent evaporation of an oil-in-water emulsion treatment (SE treatment) to induce block copolymer into polymer micelle via phase separation to refresh the sharp edges of GO. Block copolymer modified GO possessed similar dispersibility and stability to PEG modified GO, and even higher loading capacity of the hydrophobic drug than PHBV modified GO, illustrating its superior properties to homopolymer. PEG, PHBV and their block copolymer modified GO were nontoxic towards ATDC5 cells while cultured for 3 days and compatible with erythrocytes within 8 h. SE treatment enhanced greatly the loading capacity of the hydrophobic drug and the accumulative release reached 91.3% within 24 h. The inhibition zone of the block copolymer modified GO was 14.1 mm and 14.8 mm against E. coli and S. aureus, comparable to that of PEG modified GO. The bacterial reduction rate of the copolymer micelle modified GO was 87.1% and 82.7% towards E. coli and S. aureus, much greater than that of PEG, PHBV and their block copolymer modified GO at a concentration of 1 mg/mL. The antibiofilm capacity of the copolymer micelle modified GO were equal to that of PEG modified, demonstrating its great promise in tissue engineering application for repair of infected tissue defects.
Assuntos
Escherichia coli , Grafite , Micelas , Staphylococcus aureus , Polímeros/farmacologia , Polímeros/química , Polietilenoglicóis/química , Antibacterianos/farmacologia , Poliésteres/químicaRESUMO
The dynamic modification of RNA plays a crucial role in biological regulation and is strongly linked to human disease development and progression. Notably, modified nucleosides in urine have shown promising potential as early diagnostic biomarkers for various conditions. In this study, we developed and validated a rapid, sensitive, and accurate UPLC-MS/MS method for quantifying eight types of modified nucleosides (N1-methyladenosine (m1A), N6-methyladenosine (m6A), 5-methyluridine (m5U), 5-taurinomethyl-2-thiouridine (τm5s2U), 5-methylcytidine (m5C), 2'-O-methylcytidine (Cm), N1-methylguanosine (m1G), and N7-methylguanosine (m7G) in human urine. Using the method, we measured the urinary concentrations of m1A, m6A, m5U, τm5s2U, m5C, Cm, m1G, and m7G in a total of 21 control individuals and 23 patients diagnosed with diabetic retinopathy (DR). Cm levels showed promise as a diagnostic marker for diabetic retinopathy (DR), with a significant value (P < 0.01) and an AUC of 0.735. Other modified nucleosides also exhibited significant differences within specific subpopulations. As non-proliferative diabetic retinopathy (NPDR) signifies the latent early stage of diabetic retinopathy, we developed a multivariate linear model that integrates patients' sex, age, height, and urinary concentration of modified nucleosides which aims to predict and differentiate between healthy individuals, NPDR patients, and proliferative diabetic retinopathy (PDR) patients. Encouragingly, the model achieved satisfactory accuracy rates: healthy (81%), NPDR (75%), and PDR (80%). Our findings provide valuable insights into the development of an early, cost-effective, and noninvasive diagnostic approach for diabetic retinopathy.
Assuntos
Diabetes Mellitus , Retinopatia Diabética , Tiouridina/análogos & derivados , Humanos , Nucleosídeos/urina , Retinopatia Diabética/diagnóstico , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , BiomarcadoresRESUMO
Coral-dinoflagellate symbiosis is a unique biological phenomenon, in which animal cells engulf single-celled photosynthetic algae and maintain them in their cytoplasm mutualistically. Studies are needed to reveal the complex mechanisms involved in symbiotic processes, but it is difficult to answer these questions using intact corals. To tackle these issues, our previous studies established an in vitro system of symbiosis between cells of the scleractinian coral Acropora tenuis and the dinoflagellate Breviolum minutum, and showed that corals direct phagocytosis, while algae are likely engulfed by coral cells passively. Several genera of the family Symbiodiniaceae can establish symbioses with corals, but the symbiotic ratio differs depending on the dinoflagellate clades involved. To understand possible causes of these differences, this study examined whether cultured coral cells show phagocytotic activity with various dinoflagellate strains similar to those shown by intact A. tenuis. We found that (a) A. tenuis larvae incorporate Symbiodinium and Breviolum, but not Cladocopium, and very few Effrenium, (b) cultured coral cells engulfed all four species but the ratio of engulfment was significantly higher with Symbiodinium and Breviolum than Cladocopium and Effrenium, (c) cultured coral cells also phagocytosed inorganic latex beads differently than they do dinoflagellates . It is likely that cultured coral cells preferentially phagocytose Symbiodinium and Breviolum, suggesting that specific molecular mechanisms involved in initiation of symbiosis should be investigated in the future.
Assuntos
Antozoários , Dinoflagellida , Animais , Fagocitose , Simbiose , LarvaRESUMO
BACKGROUND: Digital subtraction angiography (DSA), the gold standard of cerebrovascular disease diagnosis, is limited in its diagnostic ability to evaluate arterial diameter. Intravascular ultrasonography (IVUS) has advantages in assessing stenosis and plaque nature and improves the evaluation and effectiveness of carotid artery stenting (CAS). CASE SUMMARY: Case 1: A 65-year-old man presented with a five-year history of bilateral lower limb weakness due to stroke. Physical examination showed decreased strength (5-/5) in both lower limbs. Carotid artery ultrasound, magnetic resonance angiography, and computed tomography angiography (CTA) showed a right proximal internal carotid artery (ICA) stenosis (70%-99%), acute cerebral infarction, and severe right ICA stenosis, respectively. We performed IVUS-assisted CAS to measure the stenosis and detected a low-risk plaque at the site of stenosis prior to stent implantation. Post-stent balloon dilatation was performed and postoperative IVUS demonstrated successful expansion and adherence. CTA six months postoperatively showed no significant increase in in-stent stenosis. Case 2: A 36-year-old man was admitted with a right common carotid artery (CCA) dissection detected by ultrasound. Physical examination showed no positive neurological signs. Carotid ultrasound and CTA showed lumen dilation in the proximal CCA with an intima-like structure and bulging in the proximal segment of the right CCA with strip-like low-density shadow (dissection or carotid web). IVUS-assisted DSA confirmed right CCA dissection. CAS was performed and intraoperative IVUS suggested a large residual false lumen. Post-stent balloon dilatation was performed reducing the false lumen. DSA three months postoperatively indicated good stent expansion with mild stenosis. CONCLUSION: IVUS aids decision-making during CAS by accurately assessing carotid artery wall lesions and plaque nature preoperatively, dissection and stenosis morphology intraoperatively, and visualizing and confirming CAS postoperatively.
RESUMO
BACKGROUND AND AIMS: Exploring how species diverge is vital for understanding the drivers of speciation. Factors such as geographical separation and ecological selection, hybridization, polyploidization and shifts in mating system are all major mechanisms of plant speciation, but their contributions to divergence are rarely well understood. Here we test these mechanisms in two plant species, Gentiana lhassica and G. hoae, with the goal of understanding recent allopatric species divergence on the Qinghai-Tibet Plateau (QTP). METHODS: We performed Bayesian clustering, phylogenetic analysis and estimates of hybridization using 561â 302 nuclear genomic single nucleotide polymorphisms (SNPs). We performed redundancy analysis, and identified and annotated species-specific SNPs (ssSNPs) to explore the association between climatic preference and genetic divergence. We also estimated genome sizes using flow cytometry to test for overlooked polyploidy. KEY RESULTS: Genomic evidence confirms that G. lhassica and G. hoae are closely related but distinct species, while genome size estimates show divergence occurred without polyploidy. Gentiana hoae has significantly higher average FIS values than G. lhassica. Population clustering based on genomic SNPs shows no signature of recent hybridization, but each species is characterized by a distinct history of hybridization with congeners that has shaped genome-wide variation. Gentiana lhassica has captured the chloroplast and experienced introgression with a divergent gentian species, while G. hoae has experienced recurrent hybridization with related taxa. Species distribution modelling suggested range overlap in the Last Interglacial Period, while redundancy analysis showed that precipitation and temperature are the major climatic differences explaining the separation of the species. The species differ by 2993 ssSNPs, with genome annotation showing missense variants in genes involved in stress resistance. CONCLUSIONS: This study suggests that the distinctiveness of these species on the QTP is driven by a combination of hybridization, geographical isolation, mating system differences and evolution of divergent climatic preferences.
Assuntos
Gentiana , Tibet , Filogenia , Gentiana/genética , DNA de Cloroplastos/genética , Teorema de Bayes , Variação Genética , Plantas/genética , PoliploidiaRESUMO
Arthrospira platensis phycobiliprotein peptide extracts (PPEs) exhibit potential mitigative effects on hepatic steatosis. However, the precise role of PPEs in addressing high-fat-induced nonalcoholic fatty liver disease (NAFLD), as well as the underlying mechanism, remains to be elucidated. In this study, NAFLD was induced in rats through a high-fat diet (HFD), and the rats were subsequently treated with PPEs for a duration of 10 weeks. The outcomes of this investigation demonstrate that PPE supplementation leads to a reduction in body weight gain, a decrease in the accumulation of lipid droplets within the liver tissues, alterations in hepatic lipid profile, regulation of lipolysis-related gene expression within white adipose tissues and modulation of intestinal metabolites. Notably, PPE supplementation exhibits a potential to alleviate liver damage by manipulating neutral lipid metabolism and phospholipid metabolism. Additionally, PPEs appear to enhance fat mobilization by up-regulating the gene expression levels of key factors such as HSL, TGL, UCP1 and UCP2. Furthermore, PPEs impact intestinal metabolites by reducing the levels of long-chain fatty acids while concurrently increasing the levels of short-chain fatty acids. The findings from this study unveil the potential of PPE intervention in ameliorating NAFLD through the modulation of hepatic lipid profile and the reinforcement of the fat mobilization of intestinal metabolites. Thus, PPEs exhibit noteworthy therapeutic effects in the context of NAFLD.
Assuntos
Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Metabolismo dos Lipídeos , Dieta Hiperlipídica/efeitos adversos , Peptídeos/farmacologia , Lipídeos/farmacologia , Camundongos Endogâmicos C57BLRESUMO
The microbiota in gastrointestinal tracts is recognized to play a pivotal role in the health of their hosts. Music and noise are prevalent environmental factors in human society and animal production and are reported to impact their welfare and physiological conditions; however, the information on the relationship between the microbiota, physiological status, and sound is limited. This study investigated the impact of music and white noise exposure in mice through 16s rRNA gene sequencing, enzyme assay, and qPCR. The results demonstrate that white noise induced oxidative stress in animals by decreasing serum SOD and GSH-PX activity while increasing LDH activity and MDA levels (p < 0.05). Conversely, no oxidative stress was observed in the music treatment group. The relative gene expression of IFN-γ and IL-1ß decreased in the white noise group compared to the music and control groups. The 16s rRNA gene amplicon sequencing revealed that Bacteroidetes, Firmicutes, Verrucomicrobia, and Proteobacteria were dominant among all the groups. Furthermore, the proportion of Firmicutes increased in the music treatment group but decreased in the white noise treatment group compared to the control group. In conclusion, white noise has detrimental impacts on the gut microbiota, antioxidant activity, and immunity of mice, while music is potentially beneficial.
RESUMO
Frequent marine oil spills have led to increasingly serious oil pollution along shorelines. Microbial remediation has become a research hotspot of intertidal oil pollution remediation because of its high efficiency, low cost, environmental friendliness, and simple operation. Many microorganisms are able to convert oil pollutants into non-toxic substances through their growth and metabolism. Microorganisms use enzymes' catalytic activities to degrade oil pollutants. However, microbial remediation efficiency is affected by the properties of the oil pollutants, microbial community, and environmental conditions. Feasible field microbial remediation technologies for oil spill pollution in the shorelines mainly include the addition of high-efficiency oil degrading bacteria (immobilized bacteria), nutrients, biosurfactants, and enzymes. Limitations to the field application of microbial remediation technology mainly include slow start-up, rapid failure, long remediation time, and uncontrolled environmental impact. Improving the environmental adaptability of microbial remediation technology and developing sustainable microbial remediation technology will be the focus of future research. The feasibility of microbial remediation techniques should also be evaluated comprehensively.
Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Poluição por Petróleo , Petróleo , Biodegradação Ambiental , Tecnologia , Petróleo/metabolismoRESUMO
To obtain the structure-function relationship of the polysaccharides derived from areca (Areca catechu L.) inflorescences in the aspect of its immunomodulatory ability, the plant-based polysaccharide was isolated and purified on column chromatography. The purity, primary structure and immune activity of four polysaccharide fractions (AFP, AFP1, AFP2 and AFP2a) were characterized comprehensively. The main chain of AFP2a was confirmed to be composed of â 3,6)-ß-D-Galp-(1â, with branch chains linked to the O-3 position on the main chain. The immunomodulatory activity of the polysaccharides was evaluated using the RAW264.7 cells and immunosuppression mice model. It was observed that AFP2a enabled greater NO release (49.72 µmol/L) than other fractions, significantly promoted the phagocytic activity of macrophages, and improved splenocyte proliferation and T lymphocyte phenotype in mice. The present results may shine a light on a new research direction in immunoenhancers and provide a theoretical foundation for the development and application of areca inflorescence.
Assuntos
Areca , Inflorescência , Camundongos , Animais , Areca/química , Macrófagos , Polissacarídeos/farmacologiaRESUMO
The coconut (Cocos nucifera L.) is a commercial crop widely distributed among coastal tropical regions. It provides millions of farmers with food, fuel, cosmetics, folk medicine, and building materials. Among these, oil and palm sugar are representative extracts. However, this unique living species of Cocos has only been preliminarily studied at molecular levels. Benefiting from the genomic sequence data published in 2017 and 2021, we investigated the transfer RNA (tRNA) modifications and modifying enzymes of the coconut in this survey. An extraction method for the tRNA pool from coconut flesh was built. In total, 33 species of modified nucleosides and 66 homologous genes of modifying enzymes were confirmed using a nucleoside analysis using high-performance liquid chromatography combined with high-resolution mass spectrometry (HPLC-HRMS) and homologous protein sequence alignment. The positions of tRNA modifications, including pseudouridines, were preliminarily mapped using a oligonucleotide analysis, and the features of their modifying enzymes were summarized. Interestingly, we found that the gene encoding the modifying enzyme of 2'-O-ribosyladenosine at the 64th position of tRNA (Ar(p)64) was uniquely overexpressed under high-salinity stress. In contrast, most other tRNA-modifying enzymes were downregulated with mining transcriptomic sequencing data. According to previous physiological studies of Ar(p)64, the coconut appears to enhance the quality control of the translation process when subjected to high-salinity stress. We hope this survey can help advance research on tRNA modification and scientific studies of the coconut, as well as thinking of the safety and nutritional value of naturally modified nucleosides.