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1.
Curr Biol ; 2024 Aug 08.
Article de Anglais | MEDLINE | ID: mdl-39146941

RÉSUMÉ

Chlorosis dormancy resulting from nitrogen starvation and its resuscitation upon available nitrogen contributes greatly to the fitness of cyanobacterial population under nitrogen-fluctuating environments. The reinstallation of the photosynthetic machinery is a key process for resuscitation from a chlorotic dormant state; however, the underlying regulatory mechanism is still elusive. Here, we reported that red light is essential for re-greening chlorotic Synechocystis sp. PCC 6803 (a non-diazotrophic cyanobacterium) after nitrogen supplement under weak light conditions. The expression of dark-operative protochlorophyllide reductase (DPOR) governed by the transcriptional factor RpaB was strikingly induced by red light in chlorotic cells, and its deficient mutant lost the capability of resuscitation from a dormant state, indicating DPOR catalyzing chlorophyll synthesis is a key step in the photosynthetic recovery of dormant cyanobacteria. Although light-dependent protochlorophyllide reductase is widely considered as a master switch in photomorphogenesis, this study unravels the primitive DPOR as a spark to activate the photosynthetic recovery of chlorotic dormant cyanobacteria. These findings provide new insight into the biological significance of DPOR in cyanobacteria and even some plants thriving in extreme environments.

2.
Precis Clin Med ; 7(3): pbae015, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-39139990

RÉSUMÉ

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has highlighted the pivotal role of the immune response in determining the progression and severity of viral infections. In this paper, we review the most recent studies on the complicated dynamics between SARS-CoV-2 and the host immune system, highlight the importance of understanding these dynamics in developing effective treatments and formulate potent management strategies for COVID-19. We describe the activation of the host's innate immunity and the subsequent adaptive immune response following infection with SARS-CoV-2. In addition, the review emphasizes the immune evasion strategies of the SARS-CoV-2, including inhibition of interferon production and induction of cytokine storms, along with the resulting clinical outcomes. Finally, we assess the efficacy of current treatment strategies, including antiviral drugs, monoclonal antibodies, and anti-inflammatory treatments, and discuss their role in providing immunity and preventing severe disease.

3.
Int Immunopharmacol ; 140: 112829, 2024 Jul 30.
Article de Anglais | MEDLINE | ID: mdl-39083933

RÉSUMÉ

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus, SEZ) is an essential zoonotic bacterial pathogen that can cause various inflammation, such as meningitis, endocarditis, and pneumonia. UDP-glucose dehydrogenase (hasB) is indispensable in synthesizing SEZ virulence factor hyaluronan capsules. Our study investigated the infection of hasB on mice response to SEZ by employing a constructed capsule-deficient mutant strain designated as the ΔhasB strain. This deficiency was associated with a reduced SEZ bacterial load in the mice's blood and peritoneal lavage fluid (PLF) post-infection. Besides, the ΔhasB SEZ strain exhibited a higher propensity for neutrophil infiltration and release of cell-free DNA (cfDNA) in vivo compared to the wild-type (WT) SEZ strain. In vitro experiments further revealed that ΔhasB SEZ more effectively induced the formation of neutrophil extracellular traps (NETs) containing histone 3 (H3), neutrophil elastase (NE), and DNA, than its WT counterpart. Moreover, the release of NETs was determined to be gasdermin D (GSDMD)-dependent during the infection process. Taken together, these findings underscore that the deficiency of the hasB gene in SEZ leads to enhanced GSDMD-dependent NET release from neutrophils, thereby reducing SEZ's capacity to resist NETs-mediated eradication during infection. Our finding paves the way for the development of innovative therapeutic strategies against SEZ.

4.
Zhonghua Nan Ke Xue ; 30(1): 51-59, 2024 Jan.
Article de Chinois | MEDLINE | ID: mdl-39046414

RÉSUMÉ

OBJECTIVE: To analyze the main active components and potential molecular mechanism of Yishen Tongluo Prescription (YTP) in the treatment of male infertility based on network pharmacological technology. METHODS: We searched and sorted the main active components of YTP and their individual potential targets in the databases of Systematic Pharmacology of Traditional Chinese Medicine (TCM) and Bioinformatics Analysis Tool of the Molecular Mechanism of TCM, and screened the targets related to male infertility diseases in the databases of Genecards, DisGeNET and OMIM. We made a Venn diagram by intersecting the predicted targets of YTP and those of male infertility diseases, constructed visualized networks for the association of the intersection targets and protein-protein interaction (PPI) using the Cytoscape software and STRING platform respectively, and conducted gene ontology (GO) and KEGG enrichment analyses using the DAVID database and R language "Cluster Profiler" software package respectively. RESULTS: A total of 99 active components, 250 targets of YTP, 4 397 targets of male infertility and 127 common targets were identified. GO analysis revealed that the biological processes of the common targets mainly included transcriptional regulation of RNA polymerase promoter Ⅱ, regulation of gene expressions, regulation of apoptosis, responses to estrogen, and cell responses to hypoxia. KEGG analysis showed significant enrichment of the common targets in the estrogen signaling pathway, cell apoptosis pathway, AGE-RAGE signaling pathway in diabetic complications, and TNF signaling pathway. CONCLUSION: Through network pharmacology, we identified the main active components of YTP and its multi-target and multi-pathway mechanism in the treatment of male infertility, which has paved the ground for animal and cell experiments in verifying the action mechanism of YTP on male infertility.


Sujet(s)
Médicaments issus de plantes chinoises , Infertilité masculine , Pharmacologie des réseaux , Mâle , Médicaments issus de plantes chinoises/pharmacologie , Médicaments issus de plantes chinoises/usage thérapeutique , Infertilité masculine/traitement médicamenteux , Humains , Cartes d'interactions protéiques , Médecine traditionnelle chinoise/méthodes , Biologie informatique , Gene Ontology , Apoptose/effets des médicaments et des substances chimiques
5.
Plant Physiol ; 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39028839

RÉSUMÉ

The involvement of nuclear factor Y (NF-Y) in transcriptional reprogramming during arbuscular mycorrhizal symbiosis has been demonstrated in several plant species. However, a comprehensive picture is lacking. We showed that the spatial expression of NF-YC3 was observed in cortical cells containing arbuscules via the cis-regulatory element GCC boxes. Moreover, the NF-YC3 promoter was transactivated by the combination of CYCLOPS and autoactive calcium and calmodulin-dependent kinase (CCaMK) via GCC boxes. Knockdown of NF-YC3 significantly reduced the abundance of all intraradical fungal structures and affected arbuscule size. BCP1, SbtM1, and WRI5a, whose expression associated with NF-YC3 levels, might be downstream of NF-YC3. NF-YC3 interacted with NF-YB3a, NF-YB5c, or NF-YB3b, in yeast (Saccharomyces cerevisiae) and in planta, and interacted with NF-YA3a in yeast. Spatial expression of three NF-YBs was observed in all cell layers of roots under both mock and mycorrhizal conditions. Simultaneous knockdown of three NF-YBs, but not individually, reduced the fungal colonization level, suggesting that there might be functional redundancy of NF-YBs to regulate AM symbiosis. Collectively, our data suggest that NF-YC3 and NF-YBs positively regulate AM symbiosis in tomato, and arbuscule-related NF-YC3 may be an important downstream gene of the common symbiosis signaling pathway.

6.
Front Immunol ; 15: 1304973, 2024.
Article de Anglais | MEDLINE | ID: mdl-39050854

RÉSUMÉ

Background: Evidence from observational studies and clinical trials has associated gut microbiota with infectious diseases. However, the causal relationship between gut microbiota and infectious diseases remains unclear. Methods: We identified gut microbiota based on phylum, class, order, family, and genus classifications, and obtained infectious disease datasets from the IEU OpenGWAS database. The two-sample Mendelian Randomization (MR) analysis was then performed to determine whether the gut microbiota were causally associated with different infectious diseases. In addition, we performed reverse MR analysis to test for causality. Results: Herein, we characterized causal relationships between genetic predispositions in the gut microbiota and nine infectious diseases. Eight strong associations were found between genetic predisposition in the gut microbiota and infectious diseases. Specifically, the abundance of class Coriobacteriia, order Coriobacteriales, and family Coriobacteriaceae was found to be positively associated with the risk of lower respiratory tract infections (LRTIs). On the other hand, family Acidaminococcaceae, genus Clostridiumsensustricto1, and class Bacilli were positively associated with the risk of endocarditis, cellulitis, and osteomyelitis, respectively. We also discovered that the abundance of class Lentisphaeria and order Victivallales lowered the risk of sepsis. Conclusion: Through MR analysis, we found that gut microbiota were causally associated with infectious diseases. This finding offers new insights into the microbe-mediated infection mechanisms for further clinical research.


Sujet(s)
Maladies transmissibles , Microbiome gastro-intestinal , Prédisposition génétique à une maladie , Analyse de randomisation mendélienne , Humains , Microbiome gastro-intestinal/génétique , Maladies transmissibles/microbiologie
7.
Biomater Adv ; 163: 213950, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-38972278

RÉSUMÉ

Traditional tendon engineering using cell-loaded scaffold has limited application potential due to the need of autologous cells. We hypothesize that potent mechanical loading can efficiently induce in situ Achilles tendon regeneration in a rabbit model by using a cell-free porous composite scaffold. In this study, melt-spinning was used to fabricate PGA (polyglycolic acid) and PLA (polylactic acid) filament fibers as well as non-woven PGA fibers. The PLA/PGA (4:2) filament fibers were further braided into a hybrid yarn,which was knitted into a PLA/PGA tubular mesh with potent mechanical property for sustaining natural tendon strain. The results showed that a complete cross-section of Achilles tendon created a model of full mechanical loading on the bridging scaffold, which could efficiently induce in situ tendon regeneration by promoting host cell infiltration, matrix production and tissue remodeling. Histologically, mechanical loading assisted in forming parallel aligned collagen fibers and tenocytes in a fashion similar to those of native tendon. Transmission electron microscope further demonstrated that mechanical strain induced collagen fibril development by increasing fibril diameter and forming bipolar structure, which resulted in enhanced mechanical properties. Interestingly, the synergistic effect between mechanical loading and hyaluronic acid modification was also observed on the induced tenogenic differentiation of infiltrated host fibroblasts. In conclusion, potent mechanical loading is the key inductive microenvironment for in situ tendon regeneration for this polymer-based composite scaffold with proper matrix modification, which may serve as a universal scaffold product for tendon regeneration.


Sujet(s)
Tendon calcanéen , Polyesters , Régénération , Ingénierie tissulaire , Structures d'échafaudage tissulaires , Animaux , Lapins , Structures d'échafaudage tissulaires/composition chimique , Ingénierie tissulaire/méthodes , Polyesters/composition chimique , Ténocytes , Polymères/composition chimique , Matériaux biocompatibles/composition chimique , Contrainte mécanique
8.
Foods ; 13(14)2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39063309

RÉSUMÉ

Increased food production and consumption patterns have resulted in higher urban food phosphorus footprints, leading to a series of resource and environmental problems worldwide. We quantified the food phosphorus footprint of the African city of Kisumu using substance flow analysis. Our aim was to develop Kisumu's sustainable phosphorus management framework so that the city would reduce phosphorus losses into the food system. Our results show that in the year 2023, the import and export of food phosphorus in the Kisumu food system was 2730.26 ± 2.7% t P yr-1 and 3297.05 ± 2.4% t P yr-1, respectively. There was -566.79 ± -18% t P yr-1 food phosphorus deficit in the Kisumu food system. Crop planting subsystem runoff/leaching/erosion loss, household consumption subsystem waste loss, and pit latrine subsystem blackwater loss are the major pathways of phosphorus losses into the environment and the main contributors to the food phosphorus footprint in the city. The 2030 scenario analysis shows that implementing a comprehensive scenario scheme throughout the entire lifecycle process from phosphorus input to waste disposal is the best choice for reducing phosphorus losses and suppressing the growth of food phosphorus footprint in the future. Our study shows that the food phosphorus footprint in the Kisumu food system was 0.67 kg P cap-1yr-1 in 2023, which is still at a low level but may enter a continuous upward trend with the improvement of socio-economic development of the city. In our framework, we have proposed a few essential measures that include urine separation, installation of septic tank, adjustment of dietary structure, flexible layout of sanitary disposal facilities, and separation of organic waste streams to reduce food phosphorus footprints in Kisumu. Given the similarity of cities along the shores of Lake Victoria, our calculation methods and management strategies can be applied to other cities in the region.

9.
Food Funct ; 15(15): 7951-7960, 2024 Jul 29.
Article de Anglais | MEDLINE | ID: mdl-38980698

RÉSUMÉ

Dietary short- and medium-chain fatty acids have been shown to elevate circulating ketone bodies and confer metabolic health benefits. Cow milk fat contains these lipids in a balanced mix but in relatively low concentrations. Enriching them could amplify health benefits of dairy products. Here, we used a volatility-based workflow to produce milk fat with a 2-fold enrichment of medium- and short-chain fatty acids (referred to as MSFAT). Our proof-of-concept studies in mice demonstrated that intake of MSFAT increased circulating ketone bodies, reduced blood glucose levels, and suppressed food intake. In humans, ingestion of MSFAT resulted in increased circulating ketone bodies, trended to attenuate (p = 0.07) postprandial glucose excursion, and acutely elevated energy expenditure. Our findings show that milk products enriched with MSFAT may hold significant metabolic advantages.


Sujet(s)
Lait , Animaux , Lait/composition chimique , Humains , Souris , Mâle , Femelle , Acides gras/métabolisme , Bovins , Adulte , Souris de lignée C57BL , Glycémie/métabolisme , Métabolisme énergétique , Corps cétoniques/métabolisme , Acides gras volatils/métabolisme
10.
Nat Commun ; 15(1): 5686, 2024 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-38971830

RÉSUMÉ

The assembly and disassembly of biomolecular condensates are crucial for the subcellular compartmentalization of biomolecules in the control of cellular reactions. Recently, a correlation has been discovered between the phase transition of condensates and their maturation (aggregation) process in diseases. Therefore, modulating the phase of condensates to unravel the roles of condensation has become a matter of interest. Here, we create a peptide-based phase modulator, JSF1, which forms droplets in the dark and transforms into amyloid-like fibrils upon photoinitiation, as evidenced by their distinctive nanomechanical and dynamic properties. JSF1 is found to effectively enhance the condensation of purified fused in sarcoma (FUS) protein and, upon light exposure, induce its fibrilization. We also use JSF1 to modulate the biophysical states of FUS condensates in live cells and elucidate the relationship between FUS phase transition and FUS proteinopathy, thereby shedding light on the effect of protein phase transition on cellular function and malfunction.


Sujet(s)
Peptides , Transition de phase , Protéine FUS de liaison à l'ARN , Protéine FUS de liaison à l'ARN/métabolisme , Protéine FUS de liaison à l'ARN/composition chimique , Protéine FUS de liaison à l'ARN/génétique , Humains , Peptides/composition chimique , Peptides/métabolisme , Amyloïde/métabolisme , Amyloïde/composition chimique , Condensats biomoléculaires/métabolisme , Condensats biomoléculaires/composition chimique , Lumière
11.
Food Chem X ; 23: 101568, 2024 Oct 30.
Article de Anglais | MEDLINE | ID: mdl-39022788

RÉSUMÉ

Pomelo flowers emit a strong fragrance and give aromatic odors. Volatile compounds from pomelo flowers were analyzed at three developmental stages and in the main organs by molecular sensory science. A total of 134 volatiles including 25 odorants, were analyzed by gas chromatography-mass spectrometry/pulsed flame photometric detector (GC-MS/PFPD) and multidimensional GC-MS/olfactory (MDGC-MS/O). The total volatile content varied among pomelo flowers at different developmental stages (stage-III > stage-II > stage-I) and among different organs of pomelo flowers (petal > pistil > stamen). Linalool was an important odorant with a high OAV, and floral/fruity comprised the predominant aroma profile. Four odorants, ethyl 2-methylbutanoate, linalool, ß-myrcene, and 2-butenal, were selected based on variable importance in projection (VIP) values and contributed mainly to the discrimination of pomelo flowers at three different developmental stages. Linalool, ß-myrcene, d-limonene, and ethyl hexanoate were potential markers for evaluating flavor differences in pomelo floral organs.

12.
Int J Chron Obstruct Pulmon Dis ; 19: 1491-1513, 2024.
Article de Anglais | MEDLINE | ID: mdl-38957709

RÉSUMÉ

Background: Chronic obstructive pulmonary disease (COPD) stands as a predominant cause of global morbidity and mortality. This study aims to elucidate the relationship between pyroptosis-related genes (PRGs) and COPD diagnosis in the context of immune infiltration, ultimately proposing a PRG-based diagnostic model for predicting COPD outcomes. Methods: Clinical data and PRGs of COPD patients were sourced from the GEO database. The "ConsensusClusterPlus" package was employed to generate molecular subtypes derived from PRGs that were identified through differential expression analysis and LASSO Cox analysis. A diagnostic signature including eight genes (CASP4, CASP5, ELANE, GPX4, NLRP1, GSDME, NOD1and IL18) was also constructed. Immune cell infiltration calculated by the ESTIMATE score, Stroma scores and Immune scores were also compared on the basis of pyroptosis-related molecular subtypes and the risk signature. We finally used qRT - PCR to detect the expression levels of eight genes in COPD patient and normal. Results: The diagnostic model, anchored on eight PRGs, underwent validation with an independent experimental cohort. The area under the receiver operating characteristic (ROC) curves (AUC) for the diagnostic model showcased values of 0.809, 0.765, and 0.956 for the GSE76925, GSE8545, and GSE5058 datasets, respectively. Distinct expression patterns and clinical attributes of PRGs were observed between the comparative groups, with functional analysis underscoring a disparity in immune-related functions between them. Conclusion: In this study, we developed a potential as diagnostic biomarkers for COPD and have a significant role in modulating the immune response. Such insights pave the way for novel diagnostic and therapeutic strategies for COPD.


Sujet(s)
Bases de données génétiques , Valeur prédictive des tests , Broncho-pneumopathie chronique obstructive , Pyroptose , Humains , Broncho-pneumopathie chronique obstructive/génétique , Broncho-pneumopathie chronique obstructive/diagnostic , Broncho-pneumopathie chronique obstructive/immunologie , Pyroptose/génétique , Analyse de profil d'expression de gènes , Poumon/immunologie , Mâle , Femelle , Adulte d'âge moyen , Marqueurs génétiques , Études cas-témoins , Transcriptome , Sujet âgé , Reproductibilité des résultats , Prédisposition génétique à une maladie , Pronostic
13.
J Fluoresc ; 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38861057

RÉSUMÉ

In this study, we synthesized a novel Co(II)-containing coordination compound (CP) [Co2(MMBA)2(HPT)2(H2O)2]·2H2O (1) through a solvothermal reaction of Co(NO3)6·6H2O with 3-(pyridin-2-yl)-1 H-1,2,4-triazole (HPT) and 2-(4-methylbenzoyl)benzoic acid (HMMBA). Fluorescence spectroscopy confirmed that this compound exhibited superior blue fluorescence properties compared to the original ligands. Further, aspirin (ASA) was loaded onto this CP via physical adsorption to create CP-ASA. Interestingly, the fluorescence properties of the CP decreased with the loading of the drug but were restored upon drug release. Leveraging the unique optical properties and biocompatibility of Polymer Liquid Crystal (PLC), we further encapsulated CP-ASA, forming the CP-PLC@ASA composite. The target product was confirmed through various characterization techniques including Elemental Analysis (EA), Fourier-Transform Infrared Spectroscopy (FT-IR), Powder X-Ray Diffraction (PXRD), and Thermogravimetric Analysis (TGA). Moreover, the biological activity of this composite was evaluated in vitro for osteoarthritis, and its potential mechanisms were explored.

15.
Inorg Chem ; 63(24): 11438-11449, 2024 Jun 17.
Article de Anglais | MEDLINE | ID: mdl-38833708

RÉSUMÉ

Ethanethiol (EtSH), being highly toxic, flammable, and explosive, poses significant risks to human health and safety and is capable of causing fires and explosions. Room-temperature detection using chemiresistive gas sensors is essential for managing these risks. However, the gas-sensing performance of conventional metal-oxide sensing materials may be limited by their weak interaction with EtSH at room temperature. Herein, SnO2 nanoflowers assembled with non-noble Cu-site-enriched porous nanosheets were designed and prepared by an in situ self-template pyrolysis synthesis strategy to enable highly sensitive and selective room-temperature detection of EtSH. By regulating the number of non-noble Cu sites, these nanoflowers achieved efficient EtSH sensing with a Ra/Rg value of 11.0 at 50 ppb, ensuring high selectivity, reproducibility, and stability at room temperature. Moreover, a comparative analysis of the room-temperature gas-sensing performance of SnO2 nanoflowers with non-noble Fe- or Ni-site-enriched nanosheets highlights the benefits of non-noble Cu sites for EtSH detection. Density functional theory (DFT) analysis reveals that non-noble Cu sites have a unique affinity for EtSH, offering preferential binding over other gases and explaining the outstanding sensing performance of non-noble Cu-site-enriched nanosheet-assembled SnO2 nanoflowers. The structural and interface engineering of the sensing materials presented in this work provides a promising approach for offering efficient and durable gas sensors operable at room temperature.

16.
Nat Aging ; 4(8): 1076-1088, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38834883

RÉSUMÉ

Oxidative phosphorylation, essential for energy metabolism and linked to the regulation of longevity, involves mitochondrial and nuclear genes. The functions of these genes and their evolutionary rate covariation (ERC) have been extensively studied, but little is known about whether other nuclear genes not targeted to mitochondria evolutionarily and functionally interact with mitochondrial genes. Here we systematically examined the ERC of mitochondrial and nuclear benchmarking universal single-copy ortholog (BUSCO) genes from 472 insects, identifying 75 non-mitochondria-targeted nuclear genes. We found that the uncharacterized gene CG11837-a putative ortholog of human DIMT1-regulates insect lifespan, as its knockdown reduces median lifespan in five diverse insect species and Caenorhabditis elegans, whereas its overexpression extends median lifespans in fruit flies and C. elegans and enhances oxidative phosphorylation gene activity. Additionally, DIMT1 overexpression protects human cells from cellular senescence. Together, these data provide insights into the ERC of mito-nuclear genes and suggest that CG11837 may regulate longevity across animals.


Sujet(s)
Caenorhabditis elegans , Évolution moléculaire , Longévité , Animaux , Longévité/génétique , Humains , Caenorhabditis elegans/génétique , Noyau de la cellule/génétique , Noyau de la cellule/métabolisme , Phosphorylation oxydative , Insectes/génétique , Génome d'insecte/génétique , Mitochondries/génétique , Mitochondries/métabolisme , Vieillissement de la cellule/génétique
17.
Adv Sci (Weinh) ; 11(29): e2403867, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38773950

RÉSUMÉ

Artificial micro/nanomotors using active particles hold vast potential in applications such as drug delivery and microfabrication. However, upgrading them to micro/nanorobots capable of performing precise tasks with sophisticated functions remains challenging. Bubble microthruster (BMT) is introduced, a variation of the bubble-driven microrobot, which focuses the energy from a collapsing microbubble to create an inertial impact on nearby target microparticles. Utilizing ultra-high-speed imaging, the microparticle mass and density is determined with sub-nanogram resolution based on the relaxation time characterizing the microparticle's transient response. Master curves of the BMT method are shown to be dependent on the viscosity of the solution. The BMT, controlled by a gamepad with magnetic-field guidance, precisely manipulates target microparticles, including bioparticles. Validation involves measuring the polystyrene microparticle mass and hollow glass microsphere density, and assessing the mouse embryo mass densities. The BMT technique presents a promising chip-free, real-time, highly maneuverable strategy that integrates bubble microrobot-based manipulation with precise bioparticle mass and density detection, which can facilitate microscale bioparticle characterizations such as embryo growth monitoring.

18.
Chem Biodivers ; : e202400596, 2024 May 28.
Article de Anglais | MEDLINE | ID: mdl-38804585

RÉSUMÉ

Three polysaccharides, PTC, PTH, and PTB, were extracted from Pinellia ternata using three different extraction conditions: room temperature water, hot water, and 2 % Na2CO3 solution. PTC and PTH were composed of rhamnose, glucose, galactose, mannose, glucuronic acid, galacturonic acid, and arabinose, which combine to form complex structures. PTB was composed solely of glucose and rhamnose. Further analysis indicated that PTC and PTB exhibited triple-helix structures. PTC showed the highest scavenging capacity against DPPH, superoxide anion, and hydroxyl radicals, with half maximal inhibitory concentrations (IC50) of 1004.1, 1584.1, and 1584.1 µg/mL, respectively. Additionally, PTC, PTH, and PTB were subjected to sulfation, phosphorylation, and selenization, resulting in the production of nine derivates. The distinctive absorptive bands of these derivates were determined through infrared spectroscopy. Selenized and sulfated derivates have shown significant antitumor and immunoenhancing properties. Our findings revealed that at 400 µg/mL, the inhibition rate of selenated PTB on HeLa cells was 54.2 % and that on HepG2 cells was 43.1 %. Additionally, selenized PTC displayed significant immunoenhancing activity, with a proliferation rate of 63.7 % at 400 µg/mL in RAW264.7 cells. These results provide valuable evidence supporting the consideration of polysaccharides from Pinellia ternata as a potential candidate for the development of antineoplastic drugs.

19.
Nat Commun ; 15(1): 4426, 2024 May 24.
Article de Anglais | MEDLINE | ID: mdl-38789507

RÉSUMÉ

Iron and phosphorus are essential nutrients that exist at low concentrations in surface waters and may be co-limiting resources for phytoplankton growth. Here, we show that phosphorus deficiency increases the growth of iron-limited cyanobacteria (Synechocystis sp. PCC 6803) through a PhoB-mediated regulatory network. We find that PhoB, in addition to its well-recognized role in controlling phosphate homeostasis, also regulates key metabolic processes crucial for iron-limited cyanobacteria, including ROS detoxification and iron uptake. Transcript abundances of PhoB-targeted genes are enriched in samples from phosphorus-depleted seawater, and a conserved PhoB-binding site is widely present in the promoters of the target genes, suggesting that the PhoB-mediated regulation may be highly conserved. Our findings provide molecular insights into the responses of cyanobacteria to simultaneous iron/phosphorus nutrient limitation.


Sujet(s)
Protéines bactériennes , Régulation de l'expression des gènes bactériens , Fer , Phosphore , Synechocystis , Phosphore/métabolisme , Phosphore/déficit , Synechocystis/métabolisme , Synechocystis/génétique , Fer/métabolisme , Protéines bactériennes/métabolisme , Protéines bactériennes/génétique , Régions promotrices (génétique)/génétique , Eau de mer/microbiologie , Homéostasie , Espèces réactives de l'oxygène/métabolisme
20.
Eur J Pharmacol ; 975: 176648, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-38759706

RÉSUMÉ

Opioids are used for pain relief in patients suffering from acute myocardial ischemia or infarction. Clinical and laboratory studies demonstrate that morphine treated patients or the experimental animal model suffering acute myocardial ischemia and reperfusion, may worsen myocardial viability. As transient receptor potential vanilloid 1 (TRPV1) plays important roles in pain sensation and cardio-protection, we query whether opioids may exacerbate myocardial viability via interaction with TRPV1 activity in the pain relief. We found the co-expressions of TRPV1 and opioid µ, δ and κ receptors in adult rat cardiomyocytes. Intravenous injection of morphine (0.3 mg/kg) at 20 min after induction of myocardial ischemia, in the rat model of acute myocardial ischemia and reperfusion, induced significant reduction of phosphorylated TRPV1 (p-TRPV1) in the ventricular myocardium and increase in serum cardiac troponin I (cTnI), compared with the ischemia/reperfusion controls (all P < 0.05). The effects of morphine were completely reversed by selective opioid µ, δ and κ receptor antagonists. While significant upregulation of p-TRPV1 (P < 0.05) and improvement of ±dP/dt max (all P < 0.05) were detected in the animals giving the same dose of morphine before induction of myocardial ischemia. The changes in p-TRPV1 correlate with the alterations of cTnI (r = -0.5840, P = 0.0283) and ±dP/dt max (r = 0.8084, P = 0.0005 and r = -0.8133, P = 0.0004, respectively). The findings of this study may indicate that potentiation and attenuation of TRPV1 sensitivity correlate with the improvement of the cardiac performance and the aggravation of myocardial viability, respectively, by giving morphine before and during myocardial ischemia and reperfusion.


Sujet(s)
Morphine , Lésion de reperfusion myocardique , Rat Sprague-Dawley , Canaux cationiques TRPV , Animaux , Canaux cationiques TRPV/métabolisme , Lésion de reperfusion myocardique/métabolisme , Lésion de reperfusion myocardique/traitement médicamenteux , Morphine/pharmacologie , Phosphorylation/effets des médicaments et des substances chimiques , Mâle , Rats , Facteurs temps , Myocytes cardiaques/effets des médicaments et des substances chimiques , Myocytes cardiaques/métabolisme , Analgésiques morphiniques/pharmacologie , Récepteurs aux opioïdes/métabolisme , Troponine I/métabolisme , Troponine I/sang , Myocarde/métabolisme , Myocarde/anatomopathologie
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