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1.
Mil Med Res ; 11(1): 20, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556884

RESUMO

BACKGROUND: Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury (TBI). However, the heterogeneity, multifunctionality, and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood. METHODS: Using the combined single-cell transcriptomics, metabolomics, and proteomics analysis from TBI patients and the TBI mouse model, we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests. We also characterized the underlying mechanisms both in vitro and in vivo through molecular simulations, signaling detections, gene expression regulation assessments [including dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays], primary cultures or co-cultures of neutrophils and oligodendrocytes, intracellular iron, and lipid hydroperoxide concentration measurements, as well as forkhead box protein O1 (FOXO1) conditional knockout mice. RESULTS: We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model. Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI, aggravating acute brain inflammatory damage and promoting late TBI-induced depression. In the acute stage, FOXO1 upregulated cytoplasmic Versican (VCAN) to interact with the apoptosis regulator B-cell lymphoma-2 (BCL-2)-associated X protein (BAX), suppressing the mitochondrial translocation of BAX, which mediated the antiapoptotic effect companied with enhancing interleukin-6 (IL-6) production of FOXO1high neutrophils. In the chronic stage, the "FOXO1-transferrin receptor (TFRC)" mechanism contributes to FOXO1high neutrophil ferroptosis, disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein, which contributes to the progression of late depression after TBI. CONCLUSIONS: FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI, which provides insight into the heterogeneity, reprogramming activity, and versatility of neutrophils in TBI.


Assuntos
Lesões Encefálicas Traumáticas , Neutrófilos , Animais , Humanos , Camundongos , Proteína X Associada a bcl-2/metabolismo , Encéfalo , Lesões Encefálicas Traumáticas/complicações , Depressão , Proteína Forkhead Box O1/metabolismo , Ferro
2.
J Mol Model ; 30(5): 124, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578379

RESUMO

CONTEXT: The crystal and molecular structure, electronic properties, optical parameters, and elastic properties of a 1:2 hexanitrohexaazaisowurtzitane (CL-20)/2-mercapto-1-methylimidazole (MMI) cocrystal under 0 ~ 100 GPa hydrostatic pressure were calculated. The results show that the cocrystal CL-20/MMI undergoes three structural transitions at 72 GPa, 95 GPa, and 97 GPa, respectively, and the structural transition occurs in the part of the MMI compound. Structural mutations formed new bonds S1-S2, C2-C7, and N1C5 at 72GPa, 95 GPa, and 97 GPa, respectively. Similarly, the formation of new bonds is confirmed on the basis of an analysis of the changes in lattice constants, cell volumes, and partial densities of states (PDOS) for S1, S2, C2, C7, N1, and C3 at the corresponding pressures. The optical parameters show that the pressure makes the peaks of various optical parameters of CL-20/MMI larger, and the optical activity is enhanced. The optical parameters also confirm the structural mutation of CL-20/MMI under the corresponding pressure. METHOD: CL-20/MMI was calculated by using the first-principles norm-conservative pseudopotential based on density functional theory (DFT) in the CASTEP software package. For the optimization results, the Broyden-Fletcher-Goldfarb-Shanno (BFGS) method is selected to optimize the geometry of the cocrystal in the range of 0-100 GPa. GGA/PBE (Perdew-Burke-Ernzerhof) was selected to relax the cocrystal CL-20/MMI fully without constraints at atmospheric pressure. The sampling scheme in the Brillouin zone [10] is the Monkhorst-Pack scheme, and the number of k-point grids was 2 × 2 × 2. By contrast, this study will use the LDA method to calculate.

3.
Mol Neurobiol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509397

RESUMO

Neuropathic pain (NPP) is a common type of chronic pain. Glial cells, including astrocytes (AS), are believed to play an important role in the progression of NPP. AS cells can be divided into various types based on their expression profiles, among which A1 and A2 types have clear functions. A1-type AS cells are neurotoxic, while A2-type AS cells exert neuroprotective functions. Some types of lysophosphatidic acid receptors (LPAR) have been shown to play a role in NPP. However, it remains unclear how AS cells and LPAR6 affect the occurrence and progression of NPP. In this study, we established a mouse model of chronic constriction injury (CCI) to simulate NPP. It was found that the expression of LPAR6 in AS cells of the spinal dorsal horn was increased in the CCI model, and the thresholds of mechanical and thermal pain were elevated after knocking out LPAR6, indicating that LPAR6 and AS cells participated in the occurrence of NPP. The experiment involved culturing primary AS cells and knocking down LPAR6 by Lentivirus. The results showed that the NF-κB signal pathway was activated and the number of A1-type AS cells increased in the CCI model. However, LPAR6 knockdown inhibited the NF-κB signal pathway and A1-type AS cells. The results of the mRNA sequencing and immunoprecipitation test indicate an interaction between LPAR6 and ROCK2. Inhibiting ROCK2 by Y-27632 increased mechanical and thermal pain thresholds and alleviated NPP at the molecular level. The study presents evidence that LPAR6 activates the NF-κB pathway through ROCK2 and contributes to the progression of NPP by increasing A1-type AS and decreasing A2-type AS. This suggests that LPAR6 could be a potential therapeutic target for alleviating NPP. Clinical applications that are successful can offer new therapeutic options, enhance the quality of life for patients, and potentially uncover new mechanisms for pain modulation.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38459985

RESUMO

OBJECTIVE: To search for and summarize the best evidence for themanagement of elderly patients with dysphagia. METHODS: Clinical decisions, recommended practices, evidence summaries, clinical practice guidelines, expert consensus, and systematic reviews on the management of dysphagia among elderly patients were systematically reviewed from domestic and foreign guideline websites, association websites, and Chinese and English databases according to the 6S model of evidence-based resources. The search period was between January 1, 2010 and November 1, 2023. Two researchers evaluated the quality of the included literature respectively and extracted evidence. RESULTS: A total of 14 literatures were identified, including 2 guidelines, 2 clinical decisions, 5 evidence summaries, 3 expert consensus statements, and 2 systematic reviews. Twenty-four pieces of evidence from 7 aspects were summarized, including assessment, treatment and rehabilitation, medication care, nutrition management, oral care, complication management, and psychological care. CONCLUSION: The best evidence-based recommendations for the management of dysphagia in elderly patients is summarized, it is suggested that the best evidence should be selected according to the actual situation of patients, and a personalized management plan should be formulated to improve the quality of life of patients and achieve high-quality nursing.

5.
J Agric Food Chem ; 72(13): 7167-7178, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511978

RESUMO

IAVPGEVA, an octapeptide derived from soybean 11S globulin hydrolysis, also known as SGP8, has exhibited regulatory effects on lipid metabolism, inflammation, and fibrosis in vitro. Studies using MCD and HFD-induced nonalcoholic steatohepatitis (NASH) models in mice show that SGP8 attenuates hepatic injury and metabolic disorders. Mechanistic studies suggest that SGP8 inhibits the JNK-c-Jun pathway in L02 cells and liver tissue under metabolic stress and targets DPP4 with DPP4 inhibitory activity. In conclusion, the results suggest that SGP8 is an orally available DPP4-targeting peptide with therapeutic potential in NASH.


Assuntos
Globulinas , Hepatopatia Gordurosa não Alcoólica , Proteínas de Soja , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Dipeptidil Peptidase 4/metabolismo , Fígado/metabolismo , Globulinas/metabolismo , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
6.
Nat Genet ; 56(4): 710-720, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38491323

RESUMO

Polyploidy (genome duplication) is a pivotal force in evolution. However, the interactions between parental genomes in a polyploid nucleus, frequently involving subgenome dominance, are poorly understood. Here we showcase analyses of a bamboo system (Poaceae: Bambusoideae) comprising a series of lineages from diploid (herbaceous) to tetraploid and hexaploid (woody), with 11 chromosome-level de novo genome assemblies and 476 transcriptome samples. We find that woody bamboo subgenomes exhibit stunning karyotype stability, with parallel subgenome dominance in the two tetraploid clades and a gradual shift of dominance in the hexaploid clade. Allopolyploidization and subgenome dominance have shaped the evolution of tree-like lignified culms, rapid growth and synchronous flowering characteristic of woody bamboos as large grasses. Our work provides insights into genome dominance in a remarkable polyploid system, including its dependence on genomic context and its ability to switch which subgenomes are dominant over evolutionary time.


Assuntos
Poaceae , Tetraploidia , Poaceae/genética , Poliploidia , Genômica , Transcriptoma/genética , Genoma de Planta/genética , Evolução Molecular
7.
Org Lett ; 26(15): 3164-3168, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38553426

RESUMO

The catalyst-dependent intermolecular carbonyl-alkyne metathesis (CAM) reaction of 1H-indene-1,2,3-triones with internal alkynes was realized using Ru and Co catalysts. 2-(2-Oxo-1,2-diphenylethylidene)-1H-indene-1,3(2H)-dione derivatives were obtained using a Ru catalyst, whereas S-alkyl 2-(1,3-dioxo-1,3-dihydro-2H-inden-2-ylidene)-2-phenylethanethioates were prepared using a Co catalyst. These transformations led to the synthesis of α,ß-unsaturated carbonyl compounds with a broad substrate scope, excellent regiocontrol, and gram-scale amenability. This catalytic strategy using a Co or Ru catalyst has rarely been described for other established CAM catalysts.

8.
J Affect Disord ; 354: 694-701, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38492648

RESUMO

From the perspective of the health context paradox, this study examined the relationship between adolescent victimization and depression based on the diathesis-stress model and attribution theory using a nested model. A survey was conducted on 3743 Chinese adolescents using the Bullying & Victimization Scale, Rumination Scale, Beck Depression Inventory, and Bullying Attitude Scale. The results disclosed that victimization had a positive impact on depression, rumination played a mediating role between victimization and depression, and classroom anti-bullying attitudes heightened the correlation between victimization and developing depression as well as between victimization and engaging in rumination thinking. This study provides a new cross-level perspective to reduce the occurrence of depression among bullied adolescents and further validates the health context paradox, expanding its applicability range. It also provides new experimental research references for reducing depression among bullied adolescents from a more comprehensive, cross-level perspective in the future.


Assuntos
Bullying , Vítimas de Crime , Humanos , Adolescente , Depressão , Inquéritos e Questionários , Escalas de Graduação Psiquiátrica
9.
Front Cardiovasc Med ; 11: 1352515, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38433756

RESUMO

Objective: This study aims to explore the effects of the Information-Motivation-Behavioral (IMB) Skills Model on the prevention of Venous Thromboembolism (VTE) in elderly lung cancer patients. Methods: A convenience sampling method was used to select study participants who were hospitalized for treatment between November 2022 and August 2023 at a tertiary hospital in Neijiang and met the inclusion and exclusion criteria. The control group (n = 41) received conventional health education, while the intervention group (n = 40) received health education based on the IMB Skills Model over three months. The scores of the Venous Thrombosis Knowledge, Participation in Thrombosis Prevention Willingness and Behavior Questionnaire, and Quality of Life Measurement Scale (QLQ-C30) were compared before the intervention and after three months. After three months of intervention, the hospital satisfaction and VTE incidence rates in both groups were investigated and compared. Results: After three months of intervention, the scores for the Venous Thrombosis Knowledge, (Participation in Thrombosis Prevention Willingness and Behavior Questionnaire in the intervention group were higher than those in the control group (P < 0.05). The QLQ-C30 scores in the intervention group for physical function, role function, emotional function, insomnia, appetite loss, and overall health status were higher than those in the control group (P < 0.05). The intervention group rated higher in doctor's professional skills, information provision, accessibility; nurse's professional skills, humanistic care, information provision, accessibility; team communication, services of other personnel, overall satisfaction compared to the control group (P < 0.05). The rate of VTE in the intervention group was 2.5%(1/40), and that in the control group was 19.5%(8/41). There was a significant difference (χ2 = 4.336, P = 0.037). Conclusion: Nursing interventions based on the IMB Skills Model for elderly lung cancer patients can enhance patients' understanding of venous thrombosis, increase willingness and active participation in thrombosis prevention, improve quality of life, increase hospital satisfaction, and reduce the incidence of VTE.

10.
J Multidiscip Healthc ; 17: 825-832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434485

RESUMO

Helicobacter pylori (HP) infections affect approximately one-third of children worldwide. In China, the incidence of HP infection in children ranges from approximately 30% to 60%. In addition to damaging the gastrointestinal tract mucosa, HP infection in children can negatively affect their growth and development, hematology, respiratory and hepatobiliary system, skin, nutritional metabolism, and autoimmune system. However, the rate of HP eradication also fell considerably from the previous rate due to the presence of drug-resistant HP strains and the limited types of antibiotics that can be used in young patients. Vitamin D3 (VitD3) is a steroid hormone that can reduce inflammation in the stomach mucosa induced by HP and can alleviate and eradicate HP through a variety of pathways and mechanisms, including immune regulation and the stimulation of antimicrobial peptide (AMP) secretion and Ca2+ influx, to reestablish lysosomal acidification; thus, these results provide new strategies and ideas for the eradication of drug-resistant HP strains.

12.
ACS Appl Mater Interfaces ; 16(7): 8391-8402, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324389

RESUMO

Enriching erythrocytes and platelets in seconds and providing a fast seal in bleeding sites is vital to fatal hemorrhage control. Herein, hydrophilic chitosan fibrous mats (CECS-D mats) are fabricated by introducing hydrophilic carboxyethyl groups and subsequent catechol groups onto chitosan fibers. Due to strong hydrophilicity, CECS-D mats exhibit rapid liquid-absorption capacity, especially instantaneous absorptivity to the rabbit blood, which can achieve erythrocyte and platelet aggregations quickly by concentrating blood, thus promoting the formation of blood clots. Furthermore, the mats are self-oxidated to form quinone-amine adducts or quinone multimers by adjusting pH conditions, which not only provides tissue adhesion but also induces erythrocyte aggregation and platelet adhesion, further enhancing the seal and triggering quick closure to achieve fast hemostasis. Therefore, the mats reveal superior hemostatic performance in rabbit liver and spleen models over CECS mats and gauze. Especially in the fatal femoral artery injury model of rabbits, the mats reduce the blood loss by ∼75% and shortened the bleeding time by ∼50% compared with CECS mats, which have been reported to have the same hemostatic effect as commercialized Celox products in a swine femoral artery injury model. Besides, the mats are cytocompatible and degradable as well as antibacterial. This chitosan mat is a promising hemostatic material for fatal hemorrhage control.


Assuntos
Quitosana , Hemostáticos , Coelhos , Animais , Suínos , Quitosana/farmacologia , Hemorragia/tratamento farmacológico , Hemostáticos/farmacologia , Hemostasia , Interações Hidrofóbicas e Hidrofílicas , Quinonas
13.
Heliyon ; 10(3): e25014, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38322886

RESUMO

Building on Beck's cognitive model of depression, this study examined the link between harsh parenting and adolescent depression via rumination. In addition, this study examined the moderating effect of school support. A survey of 4991 high school students in China was conducted utilizing the Harsh Parenting Scale, Rumination Responses Scale, Beck Depression Inventory, and The Multidimensional Scale of Perceived Social Support. The results of this study unveiled a positive association between harsh parenting and adolescent depression. Furthermore, it was observed that rumination partially mediated the relationship between harsh parenting and adolescent depression. Notably, the results indicated that school support exerted a negative regulatory influence on the latter part of the mediation model, demonstrating that higher levels of school support effectively mitigated the adverse impact of rumination on depression. These findings highlight the crucial role of interventions targeted at reducing harsh parenting practices and bolstering school support in mitigating adolescent depression. By addressing these factors, we can make noteworthy progress in promoting the overall well-being and mental health of adolescents.

14.
J Mol Model ; 30(3): 83, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38403784

RESUMO

CONTEXT: The influence of external electric fields (EEFs) on chemical substances has always been a hot topic in the field of theoretical chemistry research. 2,6-Diamino-3,5-dinitropyrazine-1-oxide (LLM-105) is an energetic material with excellent comprehensive properties and enormous potential for application. This article explores the molecular structure, electronic structure, energy change, frontier molecular orbitals (FMOs) and density of states (DOS), UV-Vis spectra, and infrared spectra of LLM-105 under various electric field conditions. The results indicate that negative EEF can improve the stability of LLM-105, reflected in the initiation of changes in bond length and HOMO-LOMO gap. EEF has a significant impact on the electronic structure of LLM-105. The polarization of the electronic structure brings about a change in total energy, which is reflected in the analysis of energy changes. In addition, the external electric field will cause the frequency of the infrared spectra and the UV-Vis spectra to have different degrees of blue shift. The results of the analysis are helpful to understand the changes of energetic materials under the applied electric field. METHODS: Based on the density functional theory (DFT), the structural optimization and energy calculation were carried out by using B3LYP/6-311G(d, p) and B3LYP/def2-TZVPP methods, respectively. After optimization convergence, vibration analysis was performed without imaginary frequencies to obtain stable configurations. Then, the molecular structure, electronic structure, energy changes, molecular orbital and density of states, UV-Vis spectra, and infrared spectra were analyzed.

15.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167024, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38242180

RESUMO

Oxidative stress is the common mechanism of sensorineural hearing loss (SNHL) caused by many factors, such as noise, drugs and ageing. Here, we used tert-butyl hydroperoxide (t-BHP) to cause oxidative stress damage in HEI-OC1 cells and in an in vitro cochlear explant model. We observed lipid peroxidation, iron accumulation, mitochondrial shrinkage and vanishing of mitochondrial cristae, which caused hair cell ferroptosis, after t-BHP exposure. Moreover, the number of TUNEL-positive cells in cochlear explants and HEI-OC1 cells increased significantly, suggesting that t-BHP caused the apoptosis of hair cells. Administration of deferoxamine (DFOM) significantly attenuated t-BHP-induced hair cell loss and disordered hair cell arrangement in cochlear explants as well as HEI-OC1 cell death, including via apoptosis and ferroptosis. Mechanistically, we found that DFOM treatment reduced t-BHP-induced lipid peroxidation, iron accumulation and mitochondrial pathological changes in hair cells, consequently mitigating apoptosis and ferroptosis. Moreover, DFOM treatment alleviated GSH depletion caused by t-BHP and activated the Nrf2 signalling pathway to exert a protective effect. Furthermore, we confirmed that the protective effect of DFOM mainly depended on its ability to chelate iron by constructing Fth1 knockout (KO), TfR1 KO and Nrf2 KO HEI-OC1 cell lines using CRISPR/Cas9 technology and a Flag-Fth1 (overexpression) HEI-OC1 cell line using the FlpIn™ System. Our findings suggest that DFOM is a potential drug for SNHL treatment due to its ability to inhibit apoptosis and ferroptosis by chelating iron and scavenging reactive oxygen species (ROS).


Assuntos
Desferroxamina , Ototoxicidade , Humanos , terc-Butil Hidroperóxido/toxicidade , terc-Butil Hidroperóxido/metabolismo , Desferroxamina/farmacologia , Ototoxicidade/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Células Ciliadas Auditivas/metabolismo , Ferro/metabolismo
16.
J Org Chem ; 89(2): 1235-1240, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38193431

RESUMO

Alkaline-metal-promoted divergent syntheses of 1-aminoisoquinolines and isoquinolines have been reported involving 2-methylaryl aldehydes, nitriles, and LiN(SiMe3)2 as reactants. In addition, the three-component reaction of 2-methylaryl nitriles, aldehydes, and LiN(SiMe3)2 has been developed to furnish 1-aminoisoquinolines. This protocol features readily available starting materials, excellent chemoselectivity, broad substrate scope, and satisfactory yields.

17.
Anal Methods ; 16(6): 798-816, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38259224

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) protein systems are adaptive immune systems unique to archaea and bacteria, with the characteristics of targeted recognition and gene editing to resist the invasion of foreign nucleic acids. Biosensors combined with the CRISPR/Cas system and optical detection technology have attracted much attention in medical diagnoses, food safety, agricultural progress, and environmental monitoring owing to their good sensitivity, high selectivity, and fast detection efficiency. In this review, we introduce the mechanism of CRISPR/Cas systems and developments in this area, followed by summarizing recent progress on CRISPR/Cas system-based optical biosensors combined with colorimetric, fluorescence, electrochemiluminescence and surface-enhanced Raman scattering optical techniques in various fields. Finally, we discuss the challenges and future perspectives of CRISPR/Cas systems in optical biosensors.


Assuntos
Bactérias , Sistemas CRISPR-Cas , Sistemas CRISPR-Cas/genética , Bactérias/genética , Archaea/genética , Archaea/metabolismo , Edição de Genes/métodos
18.
Angew Chem Int Ed Engl ; 63(5): e202316479, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38055193

RESUMO

Efficient ultraviolet (UV) electroluminescent materials remain a great challenge, since short peak wavelength <400 nm and narrow full width at half maximum (FWHM) <50 nm are simultaneously required. In this sense, multi-resonance (MR) thermally activated delayed fluorescence (TADF) emitters featuring narrow-band emissions hold the promise for UV applications. Herein, a novel MR-TADF skeleton featuring carbazole-phosphine oxide (P=O) fused aromatics is developed to construct the first two UV MR emitters named CzP2PO and tBCzP2PO. In addition to synergistic resonance effects of P=O and N atom, sp3 -hybrid P atom renders the curved polycyclic planes of CzP2PO and tBCzP2PO, giving rise to their narrowband UV emissions with peak wavelengths <390 nm and FWHM<35 nm. Besides configuration quasi-planarization for radiation enhancement and quenching suppression, P=O moiety further enhances singlet-triplet coupling to facilitate reverse intersystem crossing, resulting in the state-of-the-art photoluminescence quantum yield of 62 % in tBCzP2PO doped films. As consequence, tBCzP2PO endowed its UV organic light-emitting diodes with the peak at 382 nm and FWHM of 32 nm, and especially the record-high external quantum efficiency (EQE) of 15.1 % among all kinds of UV devices. Our results demonstrate great potential of P=O based MR emitters in practical applications including optoelectronics, biology and medicine science.

19.
Acta Pharmacol Sin ; 45(1): 76-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670136

RESUMO

Mechanosensitive cation channels such as Piezo1 and Piezo2 are activated by mechanical force like a starched wall of the aorta while blood pressure (BP) rising, which helps to elucidate the underlying mechanism of mechanotransduction of baroreceptor endings. In this study we investigated how Piezo1 channel activation-mediated gender- and afferent-specific BP regulation in rats. We established high-fat diet and fructose drink-induced hypertension model rats (HFD-HTN) and deoxycorticosterone (DOCA)-sensitive hypertension model rats. We showed that the expression levels of Piezo1 and Piezo2 were significantly up-regulated in left ventricle of HFD and DOCA hypertensive rats, whereas the down-regulation of Piezo1 was likely to be compensated by Piezo2 up-regulation in the aorta. Likewise, down-regulated Piezo1 was observed in the nodose ganglion (NG), while up-regulated Piezo2 was found in the nucleus tractus solitarius (NTS), which might synergistically reduce the excitatory neurotransmitter release from the presynaptic membrane. Notably, microinjection of Yoda1 (0.025-2.5 mg/ml) into the NG concentration-dependently reduced BP in both hypertensive rat models as well as in control rats with similar EC50; the effect of Yoda1 was abolished by microinjection of a Piezo1 antagonist GsMTx4 (1.0 µM). Functional analysis in an in vitro aortic arch preparation showed that instantaneous firing frequency of single Ah-fiber of aortic depressor nerve was dramatically increased by Yoda1 (0.03-1.0 µM) and blocked by GsMTx4 (1.0 µM). Moreover, spontaneous synaptic currents recorded from identified 2nd-order Ah-type baroreceptive neurons in the NTS was also facilitated over 100% by Yoda1 (1.0 µM) and completely blocked by GsMTx4 (3.0 µM). These results demonstrate that Piezo1 expressed on Ah-type baroreceptor and baroreceptive neurons in the NG and NTS plays a key role in a sexual-dimorphic BP regulation under physiological and hypertensive condition through facilitation of baroreflex afferent neurotransmission, which is presumably collaborated by Piezo2 expression at different level of baroreflex afferent pathway via compensatory and synergistic mechanisms.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Ratos , Animais , Barorreflexo , Pressão Sanguínea , Mecanotransdução Celular/fisiologia , Acetato de Desoxicorticosterona/farmacologia , Transmissão Sináptica
20.
Conserv Biol ; 38(1): e14180, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37700668

RESUMO

Current biodiversity loss is generally considered to have been caused by anthropogenic disturbance, but it is unclear when anthropogenic activities began to affect biodiversity loss. One hypothesis suggests it began with the Industrial Revolution, whereas others propose that anthropogenic disturbance has been associated with biodiversity decline since the early Holocene. To test these hypotheses, we examined the unique vegetation of evergreen broadleaved forests (EBLFs) in East Asia, where humans have affected landscapes since the early Holocene. We adopted a genomic approach to infer the demographic history of a dominant tree (Litsea elongata) of EBLFs. We used Holocene temperature and anthropogenic disturbance factors to calculate the correlation between these variables and the historical effective population size of L. elongata with Spearman statistics and integrated the maximum-entropy niche model to determine the impact of climate change and anthropogenic disturbance on fluctuation in its effective population size. We identified 9 well-defined geographic clades for the populations of L. elongata. Based on the estimated historical population sizes of these clades, all the populations contracted, indicating persistent population decline over the last 11,000 years. Demographic history of L. elongata and human population change, change in cropland use, and change in irrigated rice area were significantly negatively correlated, whereas climate change in the Holocene was not correlated with demographic history. Our results support the early human impact hypothesis and provide comprehensive evidence that early anthropogenic disturbance may contribute to the current biodiversity crisis in East Asia.


Assuntos
Efeitos Antropogênicos , Árvores , Animais , Humanos , Conservação dos Recursos Naturais , Florestas , Ásia Oriental , Biodiversidade , Mudança Climática
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