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1.
BMC Biol ; 22(1): 185, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39218872

RESUMO

BACKGROUND: Scutellaria, a sub-cosmopolitan genus, stands as one of the Lamiaceae family's largest genera, encompassing approximately 500 species found in both temperate and tropical montane regions. Recognized for its significant medicinal properties, this genus has garnered attention as a research focus, showcasing anti-cancer, anti-inflammatory, antioxidant, and hepatoprotective qualities. Additionally, it finds application in agriculture and horticulture. Comprehending Scutellaria's taxonomy is pivotal for its effective utilization and conservation. However, the current taxonomic frameworks, primarily based on morphological characteristics, are inadequate. Despite several phylogenetic studies, the species relationships and delimitations remain ambiguous, leaving the genus without a stable and reliable classification system. RESULTS: This study analyzed 234 complete chloroplast genomes, comprising 220 new and 14 previously published sequences across 206 species, subspecies, and varieties worldwide. Phylogenetic analysis was conducted using six data matrices through Maximum Likelihood and Bayesian Inference, resulting in a robustly supported phylogenetic framework for Scutellaria. We propose three subgenera, recommending the elevation of Section Anaspis to subgeneric rank and the merging of Sections Lupulinaria and Apeltanthus. The circumscription of Subgenus Apeltanthus and Section Perilomia needs to be reconsidered. Comparative analysis of chloroplast genomes highlighted the IR/SC boundary feature as a significant taxonomic indicator. We identified a total of 758 SSRs, 558 longer repetitive sequences, and ten highly variable regions, including trnK-rps16, trnC-petN, petN-psbM, accD-psaI, petA-psbJ, rpl32-trnL, ccsA-ndhD, rps15-ycf1, ndhF, and ycf1. These findings serve as valuable references for future research on species identification, phylogeny, and population genetics. CONCLUSIONS: The phylogeny of Scutellaria, based on the most comprehensive sample collection to date and complete chloroplast genome analysis, has significantly enhanced our understanding of its infrageneric relationships. The extensive examination of chloroplast genome characteristics establishes a solid foundation for the future development and utilization of Scutellaria, an important medicinal plant globally.


Assuntos
Genoma de Cloroplastos , Filogenia , Scutellaria , Scutellaria/genética
2.
Mol Phylogenet Evol ; 198: 108112, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38806075

RESUMO

Obtaining a robust phylogeny proves challenging due to the intricate evolutionary history of species, where processes such as hybridization and incomplete lineage sorting can introduce conflicting signals, thereby complicating phylogenetic inference. In this study, we conducted comprehensive sampling of Elsholtzieae, with a particular focus on its largest genus, Elsholtzia. We utilized 503 nuclear loci and complete plastome sequences obtained from 99 whole-genome sequencing datasets to elucidate the interspecific relationships within the Elsholtzieae. Additionally, we explored various sources of conflicts between gene trees and species trees. Fully supported backbone phylogenies were recovered, and the monophyly of Elsholtzia and Keiskea was not supported. Significant gene tree heterogeneity was observed at numerous nodes, particularly regarding the placement of Vuhuangia and the E. densa clade. Further investigations into potential causes of this discordance revealed that incomplete lineage sorting (ILS), coupled with hybridization events, has given rise to substantial gene tree discordance. Several species, represented by multiple samples, exhibited a closer association with geographical distribution rather than following a strictly monophyletic pattern in plastid trees, suggesting chloroplast capture within Elsholtzieae and providing evidence of hybridization. In conclusion, this study provides phylogenomic insights to untangle taxonomic problems in the tribe Elsholtzieae, especially the genus Elsholtzia.


Assuntos
Hibridização Genética , Lamiaceae , Filogenia , Lamiaceae/genética , Lamiaceae/classificação , Genoma de Planta
3.
Artigo em Inglês | MEDLINE | ID: mdl-38850333

RESUMO

AIM: To explore the molecular mechanism underlying the protective effect of hypothermic perfusion on the corneal endothelium during phacoemulsification. METHODS: Phacoemulsification was performed on New Zealand white rabbits. Perfusate at different temperatures was used during the operation, and the aqueous humor was collected for proteomic sequencing after the operation. Corneal endothelial cell injury was simulated by a corneal endothelial cell oxygen-glucose deprivation/reoxygenation (OGD/R) model in vitro. Flow cytometry and evaluation of fluorescent LC3B puncta were used to detect apoptosis and autophagy, and western blotting was used to detect protein expression. RESULTS: A total of 381 differentially expressed proteins were identified between the two groups. In vitro, 4 ℃ hypothermia significantly reduced apoptosis and promoted autophagy. Apoptosis increased after autophagy was inhibited by 3-Methyladenine (3-MA). Furthermore, adiponectin (ADIPOQ) knockdown inhibited phospho-AMPK and blocked the protective effect of hypothermia on corneal endothelial cells. CONCLUSIONS: We investigated the differential expression of proteins between the hypothermia group and normothermia group by proteomics. Moreover, hypothermia-induced ADIPOQ can reduce apoptosis by promoting AMPK-mediated autophagy.

4.
Graefes Arch Clin Exp Ophthalmol ; 261(3): 735-748, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36058948

RESUMO

PURPOSE: Oxidative stress and inflammation had been proved to play important role in the progression of diabetic keratopathy (DK). The excessive accumulation of AGEs and their bond to AGE receptor (RAGE) in corneas that cause the formation of oxygen radicals and the release of inflammatory cytokines, induce cell apoptosis. Our current study was aimed to evaluate the effect of ALA on AGEs accumulation as well as to study the molecular mechanism of ALA against AGE-RAGE axis mediated oxidative stress, apoptosis, and inflammation in HG-induced HCECs, so as to provide cytological basis for the treatment of DK. METHODS: HCECs were cultured in a variety concentration of glucose medium (5.5, 10, 25, 30, 40, and 50 mM) for 48 h. The cell proliferation was evaluated by CCK-8 assay. Apoptosis was investigated with the Annexin V- fluorescein isothiocyanate (V-FITC)/PI kit, while, the apoptotic cells were determined by flow cytometer and TUNEL cells apoptosis Kit. According to the results of cell proliferation and cell apoptosis, 25 mM glucose medium was used in the following HG experiment. The effect of ALA on HG-induced HCECs was evaluated. The HCECs were treated with 5.5 mM glucose (normal glucose group, NG group), 5.5 mM glucose + 22.5 mM mannitol (osmotic pressure control group, OP group), 25 mM glucose (high glucose group, HG group) and 25 mM glucose + ALA (HG + ALA group) for 24 and 48 h. The accumulation of intracellular AGEs was detected by ELISA kit. The RAGE, catalase (CAT), superoxide dismutase 2 (SOD2), cleaved cysteine-aspartic acid protease-3 (Cleaved caspase-3), Toll-like receptors 4 (TLR4), Nod-like receptor protein 3 (NLRP3) inflammasome, interleukin 1 beta (IL-1 ß), and interleukin 18 (IL-18) were quantified by RT-PCR, Western blotting, and Immunofluorescence, respectively. Reactive oxygen species (ROS) production was evaluated by fluorescence microscope and fluorescence microplate reader. RESULTS: When the glucose medium was higher than 25 mM, cell proliferation was significantly inhibited and apoptosis ratio was increased (P < 0.001). In HG environment, ALA treatment alleviated the inhibition of HCECs in a dose-dependent manner, 25 µM ALA was the minimum effective dose. ALA could significantly reduce the intracellular accumulation of AGEs (P < 0.001), activate protein and genes expression of CAT and SOD2 (P < 0.001), and therefore inhibited ROS-induced oxidative stress and cells apoptosis. Besides, ALA could effectively down-regulate the protein and gene level of RAGE, TLR4, NLRP3, IL-1B, IL-18 (P < 0.05), and therefore alleviated AGEs-RAGE-TLR4-NLRP3 pathway-induced inflammation in HG-induced HCECs. CONCLUSION: Our study indicated that ALA could be a desired treatment for DK due to its potential capacity of reducing accumulation of advanced glycation end products (AGEs) and down-regulating AGE-RAGE axis-mediated oxidative stress, cell apoptosis, and inflammation in high glucose (HG)-induced human corneal epithelial cells (HCECs), which may provide cytological basis for therapeutic targets that are ultimately of clinical benefit.


Assuntos
Ácido Tióctico , Humanos , Ácido Tióctico/farmacologia , Ácido Tióctico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Receptor 4 Toll-Like/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Inflamação/tratamento farmacológico , Apoptose , Glucose/toxicidade , Células Epiteliais/metabolismo , Produtos Finais de Glicação Avançada/toxicidade , Produtos Finais de Glicação Avançada/metabolismo
5.
J Transl Med ; 20(1): 475, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36266699

RESUMO

BACKGROUND: Although anxiety disorders are one of the most prevalent mental disorders, their underlying biological mechanisms have not yet been fully elucidated. In recent years, genetically determined metabolites (GDMs) have been used to reveal the biological mechanisms of mental disorders. However, this strategy has not been applied to anxiety disorders. Herein, we explored the causality of GDMs on anxiety disorders through Mendelian randomization study, with the overarching goal of unraveling the biological mechanisms. METHODS: A two-sample Mendelian randomization (MR) analysis was implemented to assess the causality of GDMs on anxiety disorders. A genome-wide association study (GWAS) of 486 metabolites was used as the exposure, whereas four different GWAS datasets of anxiety disorders were the outcomes. Notably, all datasets were acquired from publicly available databases. A genetic instrumental variable (IV) was used to explore the causality between the metabolite and anxiety disorders for each metabolite. The MR Steiger filtering method was implemented to examine the causality between metabolites and anxiety disorders. The standard inverse variance weighted (IVW) method was first used for the causality analysis, followed by three additional MR methods (the MR-Egger, weighted median, and MR-PRESSO (pleiotropy residual sum and outlier) methods) for sensitivity analyses in MR analysis. MR-Egger intercept, and Cochran's Q statistical analysis were used to evaluate possible heterogeneity and pleiotropy. Bonferroni correction was used to determine the causative association features (P < 1.03 × 10-4). Furthermore, metabolic pathways analysis was performed using the web-based MetaboAnalyst 5.0 software. All statistical analysis were performed in R software. The STROBE-MR checklist for the reporting of MR studies was used in this study. RESULTS: In MR analysis, 85 significant causative relationship GDMs were identified. Among them, 11 metabolites were overlapped in the four different datasets of anxiety disorders. Bonferroni correction showing1-linoleoylglycerophosphoethanolamine (ORfixed-effect IVW = 1.04; 95% CI 1.021-1.06; Pfixed-effect IVW = 4.3 × 10-5) was the most reliable causal metabolite. Our results were robust even without a single SNP because of a "leave-one-out" analysis. The MR-Egger intercept test indicated that genetic pleiotropy had no effect on the results (intercept = - 0.0013, SE = 0.0006, P = 0.06). No heterogeneity was detected by Cochran's Q test (MR-Egger. Q = 7.68, P = 0.742; IVW. Q = 12.12, P = 0.436). A directionality test conducted by MR Steiger confirmed our estimation of potential causal direction (P < 0.001). In addition, two significant pathways, the "primary bile acid biosynthesis" pathway (P = 0.008) and the "valine, leucine, and isoleucine biosynthesis" pathway (P = 0.03), were identified through metabolic pathway analysis. CONCLUSION: This study provides new insights into the causal effects of GDMs on anxiety disorders by integrating genomics and metabolomics. The metabolites that drive anxiety disorders may be suited to serve as biomarkers and also will help to unravel the biological mechanisms of anxiety disorders.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Humanos , Polimorfismo de Nucleotídeo Único/genética , Leucina/genética , Isoleucina/genética , Transtornos de Ansiedade/genética , Valina/genética , Ácidos e Sais Biliares
6.
Microb Pathog ; 161(Pt A): 105253, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34687837

RESUMO

PURPOSE: To investigate the composition and function of ocular surface microbiome in healthy people from different altitudes. METHODS: Thirty-two healthy people living in a high altitude region and 30 sex- and age-matched individuals living in a low altitude region were enrolled. Samples were collected from the lower conjunctival sac of one randomly chosen eye for each participant. 16S rRNA sequencing was conducted to study the bacterial community composition and predict gene function using PICRUSt software. RESULTS: Microbial diversity and richness was significantly decreased in samples from highlanders as calculated by Abundance-based Coverage Estimator (ACE) index, Chao1 index, and observed-species index (all p < 0.01). Principle coordinate analysis (PCoA) suggested significantly distinct clustering of the conjunctival sac bacterial communities between two groups (p = 0.03), especially the dominant genera. The relative abundances of Corynebacterium, Staphylococcus, and Anaerococcus were significantly enriched in highlanders, while those of Pseudomonas and Massilia were significantly decreased as compared with lowlanders (p < 0.01). In the functional annotation analysis, we found that 74 gene pathways, mainly in metabolism, differed in abundance. Pathways related to immune system diseases and infectious diseases were also enriched in highlanders. CONCLUSION: The composition and function of ocular surface microbiome in highlanders were distinct from those of lowlanders and our study may provide a reference catalog of the healthy conjunctival microbiome in highlanders.


Assuntos
Altitude , Microbiota , Bactérias/genética , Túnica Conjuntiva , Humanos , RNA Ribossômico 16S/genética
7.
J Biochem Mol Toxicol ; 35(7): e22798, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33969572

RESUMO

This study aimed to investigate the role and possible mechanism of ß-asarone in regulating neuronal apoptosis and axonal regeneration. A scratch injury was applied to cell cultures of mouse primary cortical neurons to mimic neuronal injury. The neuronal apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling staining and western blot analysis of apoptosis-related proteins. The axonal regeneration was assessed by immunofluorescent staining of ß-tubulin III and western blot analysis of axonal markers. In the results, ß-asarone inhibited neuronal apoptosis and promoted axonal regeneration by suppressing tumor necrosis factor-α (TNF-α) expression in scratch-injured mouse neuronal cells. Research investigating the molecular mechanisms by which ß-asarone inhibited TNF-α expression showed that, on the one hand, ß-asarone suppressed the JNK/c-Jun pathway and thus transcriptionally inhibited TNF-α expression; on the other hand, ß-asarone induced expression of UHRF1 that recruited DNMT1 to induce TNF-α promoter methylation and subsequently decreased the messenger RNA expression of TNF-α. In conclusion, ß-asarone suppresses TNF-α expression through DNA methylation and c-Jun-mediated transcription modulation in scratch-injured neuronal cells.


Assuntos
Derivados de Alilbenzenos/farmacologia , Anisóis/farmacologia , Metilação de DNA/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Animais , Células Cultivadas , Camundongos
8.
Biochem Biophys Res Commun ; 522(2): 395-401, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31771879

RESUMO

AIMS: Ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI), which can lead to poor outcome and increased risk of mortality. Dabrafenib (DAB) is an approved cancer treatment. Little is known about the effect of DAB in prevention or treatment of renal IRI. METHODS: For in vivo experiments, C57BL/6 mice were divided into four groups: sham (no IRI, no DAB), IRI, DAB, and DAB + IRI. IRI was induced by clamping of bilateral renal pedicles for 30 min. For in vitro experiments, HK-2 cells were used to establish the hypoxia/reoxygenation (H/R) injury model, with four groups: control (no H/R, no DAB), H/R, DAB, and DAB + H/R. Renal function and renal histological changes were recorded. Expression of NGAL and KIM-1 proteins and mRNAs were determined by western blotting and qRT-PCR; secretion of inflammatory cytokines (IL-6 and TNF- α) was determined by qRT-PCR; Cell death was determined using the TUNEL assay, measurement of cleaved caspase-3, and flow cytometry. Necroptosis-related proteins were determined by western blotting. RESULTS: In mice, DAB pretreatment improved renal function and also reduced histological injury, inflammation, cell death, and expression of necroptosis-associated proteins. In HK-2 cells, DAB significantly decreased the levels of NGAL and KIM-1, inflammatory cytokines, cell death, and necroptosis-related proteins. CONCLUSION: Our in vitro and in vivo experiments indicated that DAB appears to alleviate renal IRI by suppressing cell death and inhibiting inflammatory responses. DAB has potential use for the clinical prevention and treatment of AKI-induced IRI.


Assuntos
Imidazóis/uso terapêutico , Rim/irrigação sanguínea , Rim/patologia , Oximas/uso terapêutico , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Inflamação/patologia , Rim/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Oximas/farmacologia , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos
9.
Biol Chem ; 400(6): 753-763, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-30653462

RESUMO

The present study was designed to investigate the mechanism of the traditional Chinese medicine Changqin NO. 1 on the amelioration of traumatic brain injury (TBI). Adult male C57BL/6J mice and newborn mice were used to generate a mouse TBI model and harvest primary neurons, respectively. The localizations of specific neural markers neuropilin-1 (Nrp-1), growth-associated protein-43 (GAP-43) and microtubule-associated protein Tau (Tau) were examined in brain tissues by immunohistochemistry. Terminal deoxynucleotidyl transferase dUTP nick end labeling apoptotic cell detection in tissue sections and the CCK-8 cell viability assay were performed to examine neuronal apoptosis. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were also carried out in this study. The association between long non-coding RNA (lncRNA) growth-arrest specific 5 (GAS5), miR-335 and RAS p21 GTPase activating protein 1 (Rasa1) was disclosed using the dual-luciferase reporter assay. Changqin NO. 1 inhibited TBI-induced neuronal apoptosis in vivo and in vitro. GAS5 functioned as a competing endogenous RNA (ceRNA) by sponging miR-335 to upregulate Rasa1 expression in mouse neuronal cells. Further investigations demonstrated that GAS5 promoted neuronal apoptosis following TBI via the miR-335/Rasa1 axis. In vivo experiments indicated that Changqin NO. 1 exerted neuroprotection during TBI via the GAS5/miR-335/Rasa1 axis. Changqin NO. 1 promoted neuroprotective effects by inhibiting neuronal apoptosis via the GAS5/miR-335/Rasa1 axis in TBI.


Assuntos
Apoptose , Lesões Encefálicas Traumáticas/metabolismo , Medicina Tradicional Chinesa , Neurônios/efeitos dos fármacos , Neurônios/patologia , RNA Longo não Codificante/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Proteína p120 Ativadora de GTPase/metabolismo
10.
Biochem J ; 474(24): 4035-4051, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-28963343

RESUMO

Calmodulin (CaM) is an intracellular Ca2+ transducer involved in numerous activities in a broad Ca2+ signaling network. Previous studies have suggested that the Ca2+/CaM complex may participate in gap junction regulation via interaction with putative CaM-binding motifs in connexins; however, evidence of direct interactions between CaM and connexins has remained elusive to date due to challenges related to the study of membrane proteins. Here, we report the first direct interaction of CaM with Cx45 (connexin45) of γ-family in living cells under physiological conditions by monitoring bioluminescence resonance energy transfer. The interaction between CaM and Cx45 in cells is strongly dependent on intracellular Ca2+ concentration and can be blocked by the CaM inhibitor, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride (W7). We further reveal a CaM-binding site at the cytosolic loop (residues 164-186) of Cx45 using a peptide model. The strong binding (Kd ∼ 5 nM) observed between CaM and Cx45 peptide, monitored by fluorescence-labeled CaM, is found to be Ca2+-dependent. Furthermore, high-resolution nuclear magnetic resonance spectroscopy reveals that CaM and Cx45 peptide binding leads to global chemical shift changes of 15N-labeled CaM, but does not alter the size of the structure. Observations involving both N- and C-domains of CaM to interact with the Cx45 peptide differ from the embraced interaction with Cx50 from another connexin family. Such interaction further increases Ca2+ sensitivity of CaM, especially at the N-terminal domain. Results of the present study suggest that both helicity and the interaction mode of the cytosolic loop are likely to contribute to CaM's modulation of connexins.


Assuntos
Técnicas de Transferência de Energia por Ressonância de Bioluminescência/métodos , Cálcio/metabolismo , Calmodulina/metabolismo , Conexinas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Calmodulina/química , Conexinas/química , Transferência de Energia , Células HEK293 , Células HeLa , Humanos , Cinética , Ligação Proteica , Conformação Proteica , Homologia de Sequência , Transdução de Sinais
11.
Bioconjug Chem ; 27(9): 1972-5, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27529638

RESUMO

Here we report a facile and efficient method for site-directed glycosylation of peptide/protein. The method contains two sequential steps: generation of a GlcNAc-O-peptide/protein, and subsequent ligation of a eukaryotic N-glycan to the GlcNAc moiety. A pharmaceutical peptide, glucagon-like peptide-1 (GLP-1), and a model protein, bovine α-Crystallin, were successfully glycosylated using such an approach. It was shown that the GLP-1 with O-linked N-glycan maintained an unchanged secondary structure after glycosylation, suggesting the potential application of this approach for peptide/protein drug production. In summary, the coupled approach provides a general strategy to produce homogeneous glycopeptide/glycoprotein bearing eukaryotic N-glycans.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/metabolismo , Polissacarídeos/metabolismo , alfa-Cristalinas/metabolismo , Acetilglucosamina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Células Eucarióticas , Peptídeo 1 Semelhante ao Glucagon/química , Glicosilação , alfa-Cristalinas/química
12.
Anal Biochem ; 480: 58-66, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25862083

RESUMO

Establishing recordable channels in membranes of oocytes formed by expressing exogenous complementary DNA (cDNA) or messenger RNA (mRNA) has contributed greatly to understanding the molecular mechanisms of channel functions. Here, we report the extension of this semi-physiological system for monitoring the channel activity of preassembled membrane proteins in single cell oocytes by injecting reconstituted proteoliposomes along with substrates or regulatory molecules. We build on the observation that SecA from various bacteria forms active protein-conducting channels with injection of proteoliposomes, protein precursors, and ATP-Mg(2+). Such activity was enhanced by reconstituted SecYEG-SecDF•YajC liposome complexes that could be monitored easily and efficiently, providing correlation of in vitro and intact cell functionality. In addition, inserting reconstituted gap junction Cx26 liposomes into the oocytes allowed the demonstration of intracellular/extracellular Ca(2+)-regulated hemi-channel activities. The channel activities can be detected rapidly after injection, can be monitored for various effectors, and are dependent on specific exogenous lipid compositions. This simple and effective functional system with low endogenous channel activity should have broad applications for monitoring the specific channel activities of complex interactions of purified membrane proteins with their effectors and regulatory molecules.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Bactérias/metabolismo , Conexinas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Oócitos/metabolismo , Proteolipídeos/metabolismo , Análise de Célula Única , Animais , Linhagem Celular , Conexina 26 , Insetos , Camundongos , Canais de Translocação SEC , Proteínas SecA , Xenopus laevis/metabolismo
13.
Biochem J ; 460(2): 261-71, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24635445

RESUMO

Passive SR (sarcoplasmic reticulum) Ca2+ leak through the RyR (ryanodine receptor) plays a critical role in the mechanisms that regulate [Ca2+]rest (intracellular resting myoplasmic free Ca2+ concentration) in muscle. This process appears to be isoform-specific as expression of either RyR1 or RyR3 confers on myotubes different [Ca2+]rest. Using chimaeric RyR3-RyR1 receptors expressed in dyspedic myotubes, we show that isoform-dependent regulation of [Ca2+]rest is primarily defined by a small region of the receptor encompassing amino acids 3770-4007 of RyR1 (amino acids 3620-3859 of RyR3) named as the CLR (Ca2+ leak regulatory) region. [Ca2+]rest regulation by the CLR region was associated with alteration of RyRs' Ca2+-activation profile and changes in SR Ca2+-leak rates. Biochemical analysis using Tb3+-binding assays and intrinsic tryptophan fluorescence spectroscopy of purified CLR domains revealed that this determinant of RyRs holds a novel Ca2+-binding domain with conformational properties that are distinctive to each isoform. Our data suggest that the CLR region provides channels with unique functional properties that modulate the rate of passive SR Ca2+ leak and confer on RyR1 and RyR3 distinctive [Ca2+]rest regulatory properties. The identification of a new Ca2+-binding domain of RyRs with a key modulatory role in [Ca2+]rest regulation provides new insights into Ca2+-mediated regulation of RyRs.


Assuntos
Cálcio/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/fisiologia , Retículo Sarcoplasmático/metabolismo , Animais , Fibras Musculares Esqueléticas , Conformação Proteica , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo
14.
Phytomedicine ; 129: 155596, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38626646

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) is useful in disease treatment and prevention. Genipin is an active TCM compound used to treat diabetic retinopathy (DR). In this study, a network pharmacology (NP)-based approach was employed to investigate the therapeutic mechanisms underlying genipin administration in DR. METHODS: The potential targets of DR were identified using the gene expression omnibus (GEO) database. TCM database screening and NP were used to predict the potential active targets and pathways of genipin in DR. Cell viability was tested in vitro to determine the effects of different doses of glucose and genipin on Human Retinal Microvascular Endothelial Cells (hRMECs). CCK-8, CCK-F, colony formation, CellTiter-Lum, Annexin V-FITC, wound healing, Transwell, tube-forming, reactive oxygen species (ROS), and other assay kits were used to detect the effects of genipin on hRMECs during high levels of glucose. In vivo, a streptozotocin (STZ)-mouse intraocular genipin injection (IOI.) model was used to explore the effects of genipin on diabetes-induced retinal dysfunction. Western blotting was performed to identify the cytokines involved in proliferation, apoptosis, angiogenesis, ROS, and inflammation. The protein expression of the AKT/ PI3K/ HIF-1α and AGEs/ RAGE pathways was also examined. RESULTS: Approximately 14 types of TCM, and nearly 300 active ingredients, including genipin, were identified. The NP approach successfully identified the HIF-1α and AGEs-RAGE pathways, with the EGR1 and UCP2 genes, as key targets of genipin in DR. In the in vitro and in vivo models, we discovered that high glucose increased cell proliferation, apoptosis, angiogenesis, ROS, and inflammation. However, genipin application regulated cell proliferation and apoptosis, inhibited angiogenesis, and reduced ROS and inflammation in the HRMECs exposed to high glucose. Furthermore, the retinal thickness in the genipin-treated group was lower than that in the untreated group. AKT/ PI3K/ HIF-1α and AGEs/ RAGE signaling was increased by high glucose levels; however, genipin treatment decreased AKT/ PI3K and AGEs/ RAGE pathway expressions. Genipin also increased HIF-1α phosphorylation, oxidative phosphorylation of ATP synthesis, lipid peroxidation, and the upregulation of oxidoreductase. Genipin was found to protect HG-induced hRMECs and the retina of STZ-mice, based on; 1 the inhibition of UCP2 and Glut1 decreased intracellular glucose, and glycosylation; 2 the increased presence of HIF-1α, which increased oxidative phosphorylation and decreased substrate phosphorylation; 3 the increase in oxidative phosphorylation from ATP synthesis increased lipid peroxidation and oxidoreductase activity, and; 4 the parallel effect of phosphorylation and glycosylation on vascular endothelial growth factor (VEGF), MMP9, and Scg3. CONCLUSION: Based on NP, we demonstrated the potential targets and pathways of genipin in the treatment of DR and confirmed its effective molecular mechanism in vitro and in vivo. Genipin protects cells and tissues from high glucose levels by regulating phosphorylation and glycosylation. The activation of the HIF-1α pathway can also be used to treat DR. Our study provides new insights into the key genes and pathways associated with the prognosis and pathogenesis of DR.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Células Endoteliais , Produtos Finais de Glicação Avançada , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Glucose/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Iridoides/farmacologia , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
15.
J Neurol Surg A Cent Eur Neurosurg ; 85(3): 302-306, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-36796416

RESUMO

High intracranial pressure (ICP) can be induced by stroke, brain trauma, and brain tumor, and lead to cerebral injury. Monitoring the blood flow of a damaged brain is important for detecting intracranial lesions. Blood sampling is a better way to monitor changes in brain oxygen and blood flow than computed tomography perfusion and magnetic resonance imaging. This article describes how to take blood samples from the transverse sinus in a high ICP rat model. Also, it compares the blood samples from the transverse sinus and femoral artery/vein through blood gas analysis and neuronal cell staining. The findings may be of significance to the monitoring of the oxygen and blood flow of intracranial lesions.


Assuntos
Lesões Encefálicas , Animais , Ratos , Encéfalo/diagnóstico por imagem , Pressão Intracraniana/fisiologia , Oxigênio , Catéteres , Circulação Cerebrovascular
16.
Sci Rep ; 14(1): 19625, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39179620

RESUMO

This study explored subjective responses towards various environmental quality parameters. It would be helpful to approach an overall comfort improvement relating to physics. In order to investigate the combined effects of sound, light and heat on the overall comfort of pedestrians, which could be evaluated by overall comfort vote, two residential areas in Yubei District, Chongqing (a Cfa city in China) were selected for field measurements and questionnaires. Three were three key findings were concluded based on subjective responses to environmental parameters via multiple linear regression. First, the average outdoor neutral temperature, mean neutral sound level and neutral illumination intensity were determined to be 26.6 °C (determined by physiologically equivalent temperature), 56.5 dBA (determined by A-weighted equivalent continuous sound level) and 21.4 klx (determined by LUX), respectively. Second, considering the effects of both physiology and psychology, thermal perceptions varied for acoustic and light environments. Residents partially had lower neutral temperatures at the noisy condition. Third, environmental quality factors had a significant effect on overall comfort. Positive correlation between physiologically equivalent temperature and overall comfort vote was found (sig < 0.000); while the effects of sound pressure and light intensity were not always significant. Hence, thermal stress played a significant role in people's overall comfort. This study has explored the effects of three environment quality parameters on human perceptions. It provided better understanding against dwellers' feelings under complex circumstances. Future urban design and planning works should consider the cooling factors regarding contextual acoustical and visual environments.

17.
J Int Med Res ; 51(6): 3000605231169435, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37350283

RESUMO

Anterior inferior cerebellar artery (AICA) occlusion is a subtype of posterior circulation stroke. Confirmation of its angiomorphology and etiology is challenging because of the complex mechanisms underlying small-artery thrombogenesis. In addition to conventional factors, physicians frequently overlook hemorheological changes. In this case report, we describe right AICA occlusion in a 50-year-old man. He presented with an unsteady walk, tinnitus, dizziness, and left-sided peripheral facial palsy observed over 36 hours, accompanied by increased blood viscosity on hemorheological evaluation. Magnetic resonance imaging revealed acute infarction in the left cerebellar hemisphere and middle cerebellar peduncles. Magnetic resonance angiography (MRA) and computed tomographic angiography (CTA) failed to detect AICA occlusion, which was later confirmed using digital subtraction angiography. Repeat routine blood examinations showed elevated erythrocyte and leukocyte counts and serum hemoglobin concentrations that persisted over many days. Hemorheological evaluation revealed increased whole blood viscosity at a low shear rate. AICA occlusion should thus be diagnosed based on its initial characteristic manifestations; notably, MRA and CTA may fail to detect arterial occlusion. The importance of hemorheological change as a factor of stroke is frequently neglected. We therefore report this case hoping to emphasize its relevance, especially in small-artery occlusion.


Assuntos
Hemorreologia , Acidente Vascular Cerebral , Masculino , Humanos , Pessoa de Meia-Idade , Viscosidade Sanguínea , Cerebelo , Artéria Basilar , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia
18.
Ultrasonics ; 132: 106970, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36898297

RESUMO

Here, a physics-enhanced multi-frequency acoustic hologram deep neural network (PhysNet_MFAH) method is proposed for designing multi-frequency acoustic holograms, which is built by incorporating multiple physical models that represent the physical processes of acoustic waves propagation for a set of design frequencies into a deep neural network. It is demonstrated that one needs only to feed a set of frequency-specific target patterns into the network, the proposed PhysNet_MFAH method can automatically, accurately, and rapidly generate a high-quality multi-frequency acoustic hologram for holographic rendering of different target acoustic fields in the same or distinct regions of the target plane when driven at different frequencies. Remarkably, it is also demonstrated that the proposed PhysNet_MFAH method can achieve a higher quality of the reconstructed acoustic intensity fields than the existing optimization methods IASA and DS for designing multi-frequency acoustic holograms at a relatively fast-computational speed. Furthermore, the performance dependencies of the proposed PhysNet_MFAH method on different design parameters are established, which provide insight into the performance of the reconstructed acoustic intensity fields when subject to different design conditions of the proposed PhysNet_MFAH method. We believe that the proposed PhysNet_MFAH method can facilitate many potential applications of acoustic holograms, ranging from dynamic particle manipulation to volumetric display.

19.
World J Diabetes ; 14(9): 1349-1368, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37771331

RESUMO

BACKGROUND: Glycation is an important step in aging and oxidative stress, which can lead to endothelial dysfunction and cause severe damage to the eyes or kidneys of diabetics. Inhibition of the formation of advanced glycation end products (AGEs) and their cell toxicity can be a useful therapeutic strategy in the prevention of diabetic retinopathy (DR). Gardenia jasminoides Ellis (GJE) fruit is a selective inhibitor of AGEs. Genipin is an active compound of GJE fruit, which can be employed to treat diabetes. AIM: To confirm the effect of genipin, a vital component of GJE fruit, in preventing human retinal microvascular endothelial cells (hRMECs) from AGEs damage in DR, to investigate the effect of genipin in the down-regulation of AGEs expression, and to explore the role of the CHGA/UCP2/glucose transporter 1 (GLUT1) signal pathway in this process. METHODS: In vitro, cell viability was tested to determine the effects of different doses of glucose and genipin in hRMECs. Cell Counting Kit-8 (CCK-8), colony formation assay, flow cytometry, immunofluorescence, wound healing assay, transwell assay, and tube-forming assay were used to detect the effect of genipin on hRMECs cultured in high glucose conditions. In vivo, streptozotocin (STZ) induced mice were used, and genipin was administered by intraocular injection (IOI). To explore the effect and mechanism of genipin in diabetic-induced retinal dysfunction, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-d-glucose (2-NBDG) assays were performed to explore energy metabolism and oxidative stress damage in high glucose-induced hRMECs and STZ mouse retinas. Immunofluorescence and Western blot were used to investigate the expression of inflammatory cytokines [vascular endothelial growth factor (VEGF), SCG3, tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1ß, IL-18, and nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing 3 (NLRP3)]. The protein expression of the receptor of AGEs (RAGE) and the mitochondria-related signal molecules CHGA, GLUT1, and UCP2 in high glucose-induced hRMECs and STZ mouse retinas were measured and compared with the genipin-treated group. RESULTS: The results of CCK-8 and colony formation assay showed that genipin promoted cell viability in high glucose (30 mmol/L D-Glucose)-induced hRMECs, especially at a 0.4 µmol/L dose for 7 d. Flow cytometry results showed that high glucose can increase apoptosis rate by 30%, and genipin alleviated cell apoptosis in AGEs-induced hRMECs. A high glucose environment promoted ATP, ROS, MMP, and 2-NBDG levels, while genipin inhibited these phenotypic abnormalities in AGEs-induced hRMECs. Furthermore, genipin remarkably reduced the levels of the pro-inflammatory cytokines TNF-α, IL-1ß, IL-18, and NLRP3 and impeded the expression of VEGF and SCG3 in AGEs-damaged hRMECs. These results showed that genipin can reverse high glucose induced damage with regard to cell proliferation and apoptosis in vitro, while reducing energy metabolism, oxidative stress, and inflammatory injury caused by high glucose. In addition, ROS levels and glucose uptake levels were higher in the retina from the untreated eye than in the genipin-treated eye of STZ mice. The expression of inflammatory cytokines and pathway protein in the untreated eye compared with the genipin-treated eye was significantly increased, as measured by Western blot. These results showed that IOI of genipin reduced the expression of CHGA, UCP2, and GLUT1, maintained the retinal structure, and decreased ROS, glucose uptake, and inflammation levels in vivo. In addition, we found that SCG3 expression might have a higher sensitivity in DR than VEGF as a diagnostic marker at the protein level. CONCLUSION: Our study suggested that genipin ameliorates AGEs-induced hRMECs proliferation, apoptosis, energy metabolism, oxidative stress, and inflammatory injury, partially via the CHGA/UCP2/GLUT1 pathway. Control of advanced glycation by IOI of genipin may represent a strategy to prevent severe retinopathy and vision loss.

20.
Am J Physiol Cell Physiol ; 302(10): C1548-56, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22422398

RESUMO

Calmodulin (CaM) binding sites were recently identified on the cytoplasmic loop (CL) of at least three α-subfamily connexins (Cx43, Cx44, Cx50), while Cx40 does not have this putative CaM binding domain. The purpose of this study was to examine the functional relevance of the putative Cx43 CaM binding site on the Ca(2+)-dependent regulation of gap junction proteins formed by Cx43 and Cx40. Dual whole cell patch-clamp experiments were performed on stable murine Neuro-2a cells expressing Cx43 or Cx40. Addition of ionomycin to increase external Ca(2+) influx reduced Cx43 gap junction conductance (G(j)) by 95%, while increasing cytosolic Ca(2+) concentration threefold. By contrast, Cx40 G(j) declined by <20%. The Ca(2+)-induced decline in Cx43 G(j) was prevented by pretreatment with calmidazolium or reversed by the addition of 10 mM EGTA to Ca(2+)-free extracellular solution, if Ca(2+) chelation was commenced before complete uncoupling, after which g(j) was only 60% recoverable. The Cx43 CL(136-158) mimetic peptide, but not the scrambled control peptide, or Ca(2+)/CaM-dependent kinase II 290-309 inhibitory peptide also prevented the Ca(2+)/CaM-dependent decline of Cx43 G(j). Cx43 gap junction channel open probability decreased to zero without reductions in the current amplitudes during external Ca(2+)/ionomycin perfusion. We conclude that Cx43 gap junctions are gated closed by a Ca(2+)/CaM-dependent mechanism involving the carboxyl-terminal quarter of the connexin CL domain. This study provides the first evidence of intrinsic differences in the Ca(2+) regulatory properties of Cx43 and Cx40.


Assuntos
Calmodulina/metabolismo , Conexina 43/metabolismo , Conexinas/metabolismo , Citoplasma/metabolismo , Junções Comunicantes/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sítios de Ligação/fisiologia , Calmodulina/genética , Calmodulina/fisiologia , Linhagem Celular Tumoral , Conexina 43/genética , Conexinas/genética , Citoplasma/genética , Junções Comunicantes/genética , Junções Comunicantes/fisiologia , Humanos , Ativação do Canal Iônico/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/fisiologia , Ratos , Proteína alfa-5 de Junções Comunicantes
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