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1.
Plant Divers ; 46(4): 537-541, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39280978

RESUMO

Species richness generally decreases with increasing latitude, a biodiversity gradient that has long been considered as one of the few laws in ecology. This latitudinal diversity gradient has been observed in many major groups of organisms. In plants, the latitudinal diversity gradient has been observed in vascular plants, angiosperms, ferns, and liverworts. However, a conspicuous latitudinal diversity gradient in mosses at a global or continental scale has not been observed until now. Here, we analyze a comprehensive data set including moss species in each band of 20° in latitude worldwide. Our results show that moss species richness decreases strongly with increasing latitude, regardless of whether the globe is considered as a whole or different longitudinal segments (e.g., Old World versus New World) are considered separately. This result holds when variation in area size among latitudinal bands is taken into account. Pearson's correlation coefficient between latitude and species richness is -0.99 for both the Northern and Southern Hemispheres. Because bryophytes are an extant lineage of early land plants and because mosses not only include most of extant species of bryophytes but also are important constituents of most terrestrial ecosystems, understanding geographic patterns of mosses is particularly important. The finding of our study fills a critical knowledge gap.

2.
Nat Commun ; 15(1): 7966, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261515

RESUMO

Age is a risk factor for hematologic malignancies. Attributes of the aging hematopoietic system include increased myelopoiesis, impaired adaptive immunity, and a functional decline of the hematopoietic stem cells (HSCs) that maintain hematopoiesis. Changes in the composition of diverse HSC subsets have been suggested to be responsible for age-related alterations, however, the underlying regulatory mechanisms are incompletely understood in the context of HSC heterogeneity. In this study, we investigated how distinct HSC subsets, separated by CD49b, functionally and molecularly change their behavior with age. We demonstrate that the lineage differentiation of both lymphoid-biased and myeloid-biased HSC subsets progressively shifts to a higher myeloid cellular output during aging. In parallel, we show that HSCs selectively undergo age-dependent gene expression and gene regulatory changes in a progressive manner, which is initiated already in the juvenile stage. Overall, our studies suggest that aging intrinsically alters both cellular and molecular properties of HSCs.


Assuntos
Envelhecimento , Células-Tronco Hematopoéticas , Camundongos Endogâmicos C57BL , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/citologia , Animais , Envelhecimento/genética , Envelhecimento/fisiologia , Camundongos , Diferenciação Celular , Linhagem da Célula/genética , Hematopoese/genética , Células Mieloides/metabolismo , Células Mieloides/citologia , Masculino , Regulação da Expressão Gênica , Feminino
3.
Yi Chuan ; 46(9): 716-726, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39275871

RESUMO

Targeted precise point editing and knock-in can be achieved by homology-directed repair(HDR) based gene editing strategies in mammalian cells. However, the inefficiency of HDR strategies seriously restricts their application in precision medicine and molecular design breeding. In view of the problem that exogenous donor DNA cannot be efficiently recruited autonomously at double-stranded breaks(DSBs) when using HDR strategies for gene editing, the concept of donor adapting system(DAS) was proposed and the CRISPR/Cas9-Gal4BD DAS was developed previously. Due to the large size of SpCas9 protein, its fusion with the Gal4BD adaptor is inconvenient for protein expression, virus vector packaging and in vivo delivery. In this study, two novel CRISPR/Gal4BD-SlugCas9 and CRISPR/Gal4BD-AsCas12a DASs were further developed, using two miniaturized Cas proteins, namely SlugCas9-HF derived from Staphylococcus lugdunensis and AsCas12a derived from Acidaminococcus sp. Firstly, the SSA reporter assay was used to assess the targeting activity of different Cas-Gal4BD fusions, and the results showed that the fusion of Gal4BD with SlugCas9 and AsCas12a N-terminals had minimal distraction on their activities. Secondly, the HDR efficiency reporter assay was conducted for the functional verification of the two DASs and the corresponding donor patterns were optimized simultaneously. The results demonstrated that the fusion of the Gal4BD adaptor binding sequence at the 5'-end of intent dsDNA template (BS-dsDNA) was better for the CRISPR/Gal4BD-AsCas12a DAS, while for the CRISPR/Gal4BD-SlugCas9 DAS, the dsDNA-BS donor pattern was recommended. Finally, CRISPR/Gal4BD-SlugCas9 DAS was used to achieve gene editing efficiency of 24%, 37% and 31% respectively for EMX1, NUDT5 and AAVS1 gene loci in HEK293T cells, which was significantly increased compared with the controls. In conclusion, this study provides a reference for the subsequent optimization of the donor adapting systems, and expands the gene editing technical toolbox for the researches on animal molecular design breeding.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Humanos , Células HEK293
4.
Inorg Chem ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39270204

RESUMO

With the escalating prevalence of terrorism and global environmental pollution, nitroaromatic compounds (NACs) have increasingly come into focus as the primary culprit. To counter these challenges, it is imperative to develop simple and efficient methods for detecting NACs. Considering the electron-deficient structure of NAC molecules, this paper constructed a novel three-dimensional In-MOF with permanent porosity using electron-rich organic molecules 4'-[1,2,2-tris(3',5'-dicarboxy[1,1'-biphenyl]-4-yl)ethenyl]-[1,1'-biphenyl]-3,5-dicarboxylic acid (H8ETTB) for fluorescence detection by photoinduced electron transfer. The results indicated that In-ETTB can sensitively detect trace NACs in water. In-ETTB exhibited the best detection performance for 3-NP, achieving a Ksv value of 8.75 × 104 M-1 with a limit of detection of 0.27 µΜ in aqueous solution; this belongs to a relatively high level among the reported metal organic framework (MOF) materials. Subsequently, anti-interference experiments revealed that In-ETTB exhibits strong specificity fluorescence recognition of NACs, and it could still maintain its structural integrity and fluorescence emission intensity even after 7 cycles of testing. We confirmed that the fluorescence detection of NACs was due to a combined effect of competitive absorption and photoinduced electron transfer through experimental collaboration DFT calculations in detail. Meanwhile, the proton conductivity reached 2.45 × 10-2 S·cm-1 at 98% relative humidity and 90 °C, which is also a high level in MOFs. This work provides a universal method theoretical basis for designing NAC detectors with practical application prospects.

5.
ACS Appl Mater Interfaces ; 16(35): 46270-46279, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39171457

RESUMO

Electrocatalytic CO2 reduction serves as an effective strategy to tackle energy crises and mitigate greenhouse gas effects. The development of efficient and cost-effective electrocatalysts has been a research hotspot in the field. In this study, we designed four Co-doped single-atom catalysts (Co-Nχ@C) using carbon nanotubes as carriers, these catalysts included tri- and dicoordinated N-doped carbon nanoribbons, as well as tri- and dicoordinated N-doped graphene, respectively denoted as H3(H2)-Co/CNT and 3(2)-Co/CNT. The stable configurations of these Co-Nχ@C catalysts were optimized using the PBE+D3 method. Additionally, we explored the reaction mechanisms of these catalysts for the electrocatalytic reduction of CO2 into four C1 products, including CO, HCOOH, CH3OH and CH4, in detail. Upon comparing the limiting potentials (UL) across the Co-Nχ@C catalysts, the activity sequence for the electrocatalytic reduction of CO2 was H2-Co/CNT > 3-Co/CNT > H3-Co/CNT > 2-Co/CNT. Meanwhile, our investigation of the hydrogen evolution reaction (HER) with four catalysts elucidated the influence of acidic conditions on the electrocatalytic CO2 reduction process. Specifically, controlling the acidity of the solution was crucial when using the H3-Co/CNT and H2-Co/CNT catalysts, while the 3-Co/CNT and 2-Co/CNT catalysts were almost unaffected by the solution's acidity. We hope that our research will provide a theoretical foundation for designing more effective CO2 reduction electrocatalysts.

6.
Signal Transduct Target Ther ; 9(1): 193, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39090109

RESUMO

Cardiac myxoma is a commonly encountered tumor within the heart that has the potential to be life-threatening. However, the cellular composition of this condition is still not well understood. To fill this gap, we analyzed 75,641 cells from cardiac myxoma tissues based on single-cell sequencing. We defined a population of myxoma cells, which exhibited a resemblance to fibroblasts, yet they were distinguished by an increased expression of phosphodiesterases and genes associated with cell proliferation, differentiation, and adhesion. The clinical relevance of the cell populations indicated a higher proportion of myxoma cells and M2-like macrophage infiltration, along with their enhanced spatial interaction, were found to significantly contribute to the occurrence of embolism. The immune cells surrounding the myxoma exhibit inhibitory characteristics, with impaired function of T cells characterized by the expression of GZMK and TOX, along with a substantial infiltration of tumor-promoting macrophages expressed growth factors such as PDGFC. Furthermore, in vitro co-culture experiments showed that macrophages promoted the growth of myxoma cells significantly. In summary, this study presents a comprehensive single-cell atlas of cardiac myxoma, highlighting the heterogeneity of myxoma cells and their collaborative impact on immune cells. These findings shed light on the complex pathobiology of cardiac myxoma and present potential targets for intervention.


Assuntos
Neoplasias Cardíacas , Mixoma , Microambiente Tumoral , Humanos , Mixoma/patologia , Mixoma/genética , Mixoma/imunologia , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Neoplasias Cardíacas/genética , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/imunologia , Macrófagos/imunologia , Macrófagos/patologia , Proliferação de Células/genética , Masculino , Feminino
7.
Inflammation ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052180

RESUMO

Acute respiratory distress syndrome (ARDS) and acute lung injury (ALI) are life-threatening diseases. Neutrophil extracellular traps (NETs) play a key role in lung damage. Geranylgeranyl diphosphate synthase (GGPPS) is associated with the development of inflammatory diseases. We aimed to explore the role of GGPPS in NETs formation in ARDS/ALI. First, lung pathological changes in lipopolysaccharide (LPS)-induced ALI mice after myeloid-specific GGPPS deletion were evaluated. The level of NETs formation was analyzed by immunofluorescence, PicoGreen assay and Western blotting. Next, we determined the role of GGPPS in NETs formation and underlying mechanisms using immunofluorescence, flow cytometry, DCFH-DA, and SYTOX GREEN staining in vitro. Finally, the correlation between GGPPS expression incirculating neutrophils and dsDNA levels in plasma was evaluated. Myeloid-specific GGPPS deletion mice showed increased NETs deposition in lung tissue and aggravated histopathological damage of lung tissue. In vitro, GGPPS deficiency in neutrophils resulted in increased NETs formation by Phorbol-12-myristate-13-acetate (PMA), which was reversed by Geranylgeranyl diphosphate (GGPP). In addition, inhibitors blocking protein kinase C (PKC) and NADPH-oxidase (NOX) decreased NETs formation induced by GGPPS deletion. Importantly, GGPPS expression in circulating neutrophils was decreased in ARDS patients compared with the healthy control, and the level of dsDNA in plasma of ARDS patients was negatively correlated with the GGPPS expression. Taken together, GGPPS deficiency in neutrophils aggravates LPS-induced lung injury by promoting NETs formation via PKC/NOX signaling. Thus, neutrophil GGPPS could be a key therapeutic target for ARDS.

8.
Int J Epidemiol ; 53(4)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38990179

RESUMO

BACKGROUND: This study aimed to estimate population-level and state-level lead-attributable mortality burdens stratified by socioeconomic status (SES) class in the USA. METHODS: Based on the National Health and Nutrition Examination Survey (NHANES), we constructed individual-level SES scores from income, employment, education and insurance data. We assessed the association between the blood lead levels (BLL) and all-cause mortality by Cox regression in the NHANES cohort (n = 31 311, 4467 deaths). With estimated hazard ratios (HR) and prevalences of medium (2-5 µg/dL) and high (≥ 5 µg/dL) BLL, we computed SES-stratified population-attributable fractions (PAFs) of all-cause mortality from lead exposure across 1999-2019. We additionally conducted a systematic review to estimate the lead-attributable mortality burden at state-level. RESULTS: The HR for every 2-fold increase in the BLL decreased from 1.23 (1.10-1.38) for the lowest SES class to 1.05 (0.90-1.23) for the highest SES class. Across all SES quintiles, medium BLL exhibited a greater mortality burden. Individuals with lower SES had higher lead-attributable burdens, and such disparities haver persisted over the past two decades. In 2017-19, annually 67 000 (32 000-112 000) deaths in the USA were attributable to lead exposure, with 18 000 (2000-41 000) of these deaths occurring in the lowest SES class. Substantial disparities in the state-level mortality burden attributable to lead exposure were also highlighted. CONCLUSIONS: These findings suggested that disparities in lead-attributable mortality burden persisted within US adults, due to heterogeneities in the effect sizes of lead exposure as well as in the BLL among different SES classes.


Assuntos
Chumbo , Inquéritos Nutricionais , Classe Social , Humanos , Estados Unidos/epidemiologia , Feminino , Masculino , Chumbo/sangue , Chumbo/efeitos adversos , Pessoa de Meia-Idade , Adulto , Idoso , Intoxicação por Chumbo/mortalidade , Exposição Ambiental/efeitos adversos , Modelos de Riscos Proporcionais , Mortalidade/tendências , Adulto Jovem , Prevalência
9.
iScience ; 27(7): 110377, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39055922

RESUMO

In this study, the theoretical calculations proves that the combination of oxygen vacancy and amorphous carbon films in TiO2 (VO-CT) can effectively reduce the energy bandgap and work function. The minimum Gibbs free energies required for the CO2RR reaction of VO-CT are 0.20 eV, which is lower than pure TiO2. The amorphous c@TiO2 nanomaterials with oxygen vacancy and mesoporous structures (VO-MCT) are prepared with the P123 surfactant as the template and oxalic acid as an inducer. The electron paramagnetic resonance indicates the presence of abundant oxygen vacancy defects in the samples. UV-vis spectra indicate that the mesoporous structure enhances light absorption capacity. The photocatalytic CO2 reduction tests show that the highest conversion rates for CH4 and CO of VO-MCT are 14 µmol g-1 h-1 and 10.66 µmol g-1 h-1, respectively. The electron consumption rate of VO-MCT is 12.43 times higher than that of commercial TiO2 (P200).

10.
Arthrosc Tech ; 13(6): 102866, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39036398

RESUMO

A bony Bankart lesion is a condition where the labroligamentous complex is detached from the anterior glenoid rim, often accompanied by a fracture. It is a common occurrence found in up to 70% of traumatic shoulder dislocations. Arthroscopic surgery has become the mainstream approach for treating this condition. However, the commonly used techniques, such as labrum alone, transosseous, and double-row, can encounter difficulties passing sutures and may cause damage to the surrounding tissues, especially when dealing with large bony fragments. In this technical note, we describe our preferred technique for fixing bony Bankart lesions, which involves fixing the bony Bankart fragment through the bone tunnel using an all-suture anchor. The surgery is performed with the patient in the lateral decubitus position. Our technique offers a reliable and effective approach to treat bony Bankart lesions while minimizing the risks of complications associated with conventional techniques.

11.
Sci Adv ; 10(29): eadn8706, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028816

RESUMO

Poly(l-lactic acid) (PLLA) is a widely used U.S. Food and Drug Administration-approved implantable biomaterial that also possesses strong piezoelectricity. However, the intrinsically low stability of its high-energy piezoelectric ß phase and random domain orientations associated with current synthesis approaches remain a critical roadblock to practical applications. Here, we report an interfacial anchoring strategy for fabricating core/shell PLLA/glycine (Gly) nanofibers (NFs) by electrospinning, which show a high ratio of piezoelectric ß phase and excellent orientation alignment. The self-assembled core/shell structure offers strong intermolecular interactions between the -OH groups on Gly and C=O groups on PLLA, which promotes the crystallization of oriented PLLA polymer chains and stabilizes the ß phase structure. As-received core/shell NFs exhibit substantially enhanced piezoelectric performance and excellent stability. An all NF-based nonwoven fabric is fabricated and assembled as a flexible nanogenerator. The device offers excellent conformality to heavily wrinkled surfaces and thus can precisely detect complex physiological motions often found from biological organs.


Assuntos
Materiais Biocompatíveis , Nanofibras , Poliésteres , Nanofibras/química , Materiais Biocompatíveis/química , Poliésteres/química , Próteses e Implantes , Têxteis , Glicina/química
12.
Cell Death Dis ; 15(6): 440, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909035

RESUMO

The transmembrane death receptor Fas transduces apoptotic signals upon binding its ligand, FasL. Although Fas is highly expressed in cancer cells, insufficient cell surface Fas expression desensitizes cancer cells to Fas-induced apoptosis. Here, we show that the increase in Fas microaggregate formation on the plasma membrane in response to the inhibition of endocytosis sensitizes cancer cells to Fas-induced apoptosis. We used a clinically accessible Rho-kinase inhibitor, fasudil, that reduces endocytosis dynamics by increasing plasma membrane tension. In combination with exogenous soluble FasL (sFasL), fasudil promoted cancer cell apoptosis, but this collaborative effect was substantially weaker in nonmalignant cells. The combination of sFasL and fasudil prevented glioblastoma cell growth in embryonic stem cell-derived brain organoids and induced tumor regression in a xenograft mouse model. Our results demonstrate that sFasL has strong potential for apoptosis-directed cancer therapy when Fas microaggregate formation is augmented by mechano-inhibition of endocytosis.


Assuntos
Apoptose , Endocitose , Proteína Ligante Fas , Receptor fas , Humanos , Endocitose/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Animais , Proteína Ligante Fas/metabolismo , Receptor fas/metabolismo , Camundongos , Linhagem Celular Tumoral , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Glioblastoma/patologia , Glioblastoma/metabolismo , Glioblastoma/tratamento farmacológico
13.
Int Immunopharmacol ; 137: 112467, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38875997

RESUMO

BACKGROUND: Articular cartilage defects (ACD) are injuries with a diameter greater than 3 mm, resulting from wear and tear on joints. When the diameter of the defect exceeds 6 mm, it can further damage the surrounding joint cartilage, causing osteoarthritis (OA). Try to explain why OA is an irreversible disease, we hypothesize that damaged articular chondrocytes (DAC) may have reduced capacities to repair cartilage because its extracellular vesicle (EVs) that might directly contribute to OA formation. METHODS: In this study, DAC-EVs and AC-EVs were isolated using ultracentrifugation. Next-generation sequencing was employed to screen for a pathogenic long non-coding RNA (lncRNA). After verifying its function in vitro, the corresponding small interfering RNA (siRNA) was constructed and loaded into extracellular vesicles, which were then injected into the knee joint cavities of rats. RESULTS: The results revealed that DAC-EVs packaged lncRNA LOC102546541 acts as a competitive endogenous RNA (ceRNA) of MMP13, down-regulating miR-632. Consequently, the function of MMP13 in degrading the extracellular matrix is enhanced, promoting the development of osteoarthritis. CONCLUSIONS: This study uncovered a novel mode of OA pathogenesis using rat models, which DAC deliver pathogenic LOC102546541 packaged EVs to normal articular chondrocytes, amplifying the degradation of the extracellular matrix. Nonetheless, the functions of highly homologous human gene of LOC102546541 need to be verified in the future.


Assuntos
Cartilagem Articular , Condrócitos , Modelos Animais de Doenças , Vesículas Extracelulares , Metaloproteinase 13 da Matriz , MicroRNAs , Osteoartrite , RNA Longo não Codificante , Animais , Vesículas Extracelulares/metabolismo , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Condrócitos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos , Osteoartrite/metabolismo , Osteoartrite/patologia , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 13 da Matriz/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos Sprague-Dawley , Masculino , Humanos , Células Cultivadas , RNA Interferente Pequeno/genética
14.
Front Pharmacol ; 15: 1359939, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38933676

RESUMO

Heart failure is the most costly cardiovascular disorder. New treatments are urgently needed. This study aims to evaluate the safety, pharmacokinetics, and pharmacodynamic profile of HEC95468, a soluble guanylate cyclase (sGC) stimulator, in healthy volunteers. Sixty-two, eighteen, and forty-eight participants were enrolled in the single ascending dose (SAD) study, the food effect (FE) study, and the multiple ascending dose (MAD) study, respectively. The study conforms to good clinical practice and the Declaration of Helsinki. Overall, HEC95468 was safe and tolerable; a higher proportion of HEC95468-treated participants reported mild headaches, dizziness, decreased blood pressure, increased heart rate, and gastrointestinal-related treatment-emergent adverse events (TEAEs), similar to the sGC stimulators riociguat and vericiguat. In terms of pharmacokinetic parameters, the maximum observed plasma concentration (Cmax) and the area under the concentration-time curve (AUC0-t) were dose-proportional over the dose range. Moderate accumulation was observed after multiple administrations of HEC95468. Systolic blood pressure (SBP) and diastolic blood pressure decreased, while 3',5'-cyclic guanosine monophosphate (cGMP) concentration in plasma increased and heart rate was induced. Vasoactive hormones (renin, angiotensin II, and norepinephrine) in plasma were compensatorily elevated after oral administration. These data supported further clinical trials of HEC95468 in the treatment of heart failure and pulmonary arterial hypertension. Systematic Review Registration: http://www.chinadrugtrials.org.cn, identifier CTR20210064.

16.
Ann Bot ; 134(3): 427-436, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-38795069

RESUMO

BACKGROUND AND AIMS: Latitudinal diversity gradients have been intimately linked to the tropical niche conservatism hypothesis, which posits that there has been a strong filter due to the challenges faced by ancestral tropical lineages to adapt to low temperatures and colonize extra-tropical regions. In liverworts, species richness is higher towards the tropics, but the centres of diversity of the basal lineages are distributed across extra-tropical regions, pointing to the colonization of tropical regions by phylogenetically clustered assemblages of species of temperate origin. Here, we test this hypothesis through analyses of the relationship between macroclimatic variation and phylogenetic diversity in Chinese liverworts. METHODS: Phylogenetic diversity metrics and their standardized effect sizes for liverworts in each of the 28 regional floras at the province level in China were related to latitude and six climate variables using regression analysis. We conducted variation partitioning analyses to determine the relative importance of each group of climatic variables. KEY RESULTS: We find that the number of species decreases with latitude, whereas phylogenetic diversity shows the reverse pattern, and that phylogenetic diversity is more strongly correlated with temperature-related variables compared with precipitation-related variables. CONCLUSIONS: We interpret the opposite patterns observed in phylogenetic diversity and species richness in terms of a more recent origin of tropical diversity coupled with higher extinctions in temperate regions.


Assuntos
Biodiversidade , Clima , Hepatófitas , Filogenia , China , Hepatófitas/genética , Hepatófitas/fisiologia , Hepatófitas/classificação , Clima Tropical
17.
Int J Biol Sci ; 20(7): 2727-2747, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725857

RESUMO

Phenotypic switching (from contractile to synthetic) of vascular smooth muscle cells (VSMCs) is essential in the progression of atherosclerosis. The damaged endothelium in the atherosclerotic artery exposes VSMCs to increased interstitial fluid shear stress (IFSS). However, the precise mechanisms by which increased IFSS influences VSMCs phenotypic switching are unrevealed. Here, we employed advanced numerical simulations to calculate IFSS values accurately based on parameters acquired from patient samples. We then carefully investigated the phenotypic switching and extracellular vesicles (EVs) secretion of VSMCs under various IFSS conditions. By employing a comprehensive set of approaches, we found that VSMCs exhibited synthetic phenotype upon atherosclerotic IFSS. This synthetic phenotype is the upstream regulator for the enhanced secretion of pro-calcified EVs. Mechanistically, as a mechanotransducer, the epidermal growth factor receptor (EGFR) initiates the flow-based mechanical cues to MAPK signaling pathway, facilitating the nuclear accumulation of the transcription factor krüppel-like factor 5 (KLF5). Furthermore, pharmacological inhibiting either EGFR or MAPK signaling pathway blocks the nuclear accumulation of KLF5 and finally results in the maintenance of contractile VSMCs even under increased IFSS stimulation. Collectively, targeting this signaling pathway holds potential as a novel therapeutic strategy to inhibit VSMCs phenotypic switching and mitigate the progression of atherosclerosis.


Assuntos
Receptores ErbB , Vesículas Extracelulares , Fatores de Transcrição Kruppel-Like , Músculo Liso Vascular , Miócitos de Músculo Liso , Estresse Mecânico , Vesículas Extracelulares/metabolismo , Receptores ErbB/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Líquido Extracelular/metabolismo , Fenótipo , Animais , Aterosclerose/metabolismo , Sistema de Sinalização das MAP Quinases , Transdução de Sinais
19.
Plant Divers ; 46(3): 283-293, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38798729

RESUMO

The effect of evolutionary history on wood density variation may play an important role in shaping variation in wood density, but this has largely not been tested. Using a comprehensive global dataset including 27,297 measurements of wood density from 2621 tree species worldwide, we test the hypothesis that the legacy of evolutionary history plays an important role in driving the variation of wood density among tree species. We assessed phylogenetic signal in different taxonomic (e.g., angiosperms and gymnosperms) and ecological (e.g., tropical, temperate, and boreal) groups of tree species, explored the biogeographical and phylogenetic patterns of wood density, and quantified the relative importance of current environmental factors (e.g., climatic and soil variables) and evolutionary history (i.e., phylogenetic relatedness among species and lineages) in driving global wood density variation. We found that wood density displayed a significant phylogenetic signal. Wood density differed among different biomes and climatic zones, with higher mean values of wood density in relatively drier regions (highest in subtropical desert). Our study revealed that at a global scale, for angiosperms and gymnosperms combined, phylogeny and species (representing the variance explained by taxonomy and not direct explained by long-term evolution process) explained 84.3% and 7.7% of total wood density variation, respectively, whereas current environment explained 2.7% of total wood density variation when phylogeny and species were taken into account. When angiosperms and gymnosperms were considered separately, the three proportions of explained variation are, respectively, 84.2%, 7.5% and 6.7% for angiosperms, and 45.7%, 21.3% and 18.6% for gymnosperms. Our study shows that evolutionary history outpaced current environmental factors in shaping global variation in wood density.

20.
Plant Divers ; 46(2): 149-157, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38807907

RESUMO

Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation, extinction, and dispersal have influenced current distributions. Here, we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world. We identify centers of paleo-endemism and neo-endemism of angiosperm genera, and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions, particularly in Asia and Australia. Different categories of phylogenetic endemism centers can be differentiated using current climate conditions. Current climate, historical climate change, and geographic variables together explained ∼80% of global variation in taxonomic and phylogenetic endemism, while 42-46%, 1%, and 15% were independently explained by these three types of variables, respectively. Thus our findings show that past climate change, current climate, and geography act together in shaping endemism, which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism. Our study showed that many centers of phylogenetic endemism of angiosperms, including regions in Amazonia, Venezuela, and west-central tropical Africa that have not previously been identified as biodiversity hotspots, are missed by taxon-based measures of endemism, indicating the importance of including evolutionary history in biodiversity assessment.

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