查找使用阿拉丁产品的科研文献

The bioactive components of Coreopsis tinctoria (Asteraceae) capitula: Antioxidant activity in vitro and profile in rat plasma

Zhiyuan Ma,Shirui Zheng,Haixia Han,Jie Meng,Xi Yang,Su Zeng,Hui Zhou,Huidi Jiang

The antioxidant components of Coreopsis tinctoria have not been clearly identified; thus, here eleven constituents were isolated and identified from the capitula of Coreopsis tinctoria , in which taxifolin ( 7 ), 3,5-di-O-caffeoylquinic acid ( 9 ) and 4,5-di-O-caffeoylquinic acid ( 10 ) were identified for the first time. All eleven compounds possessed antioxidant activities based on DPPH assay and cellular antioxidant activity assay. Especially, okanin ( 11 ) and isookanin ( 6 ) exhibited excellent DPPH scavenging activities with the EC 50 of 6.2 and 10.6 µM, respectively, which were stronger than those of ascorbic acid and butylated hydroxytoluene (positive controls) with the EC 50 of 30.4 and 45.8 µM, respectively. Okanin and isookanin showed comparable cellular antioxidant activities to quercetin with the IC 50 of 11.0 and 14.4 µM, respectively. Additionally, the two most potent antioxidants, okanin and isookanin, were detectable and reached maximal concentration of 10.5 and 10.6 µM in plasma at 20 min after oral administration of 100 mg/kg ethanol extract of Coreopsis tinctoria capitula. In conclusion, our results indicate that Coreopsis tinctoria capitula might be developed as antioxidant sources.

In vitro characterization of pH-sensitive Bletilla Striata polysaccharide copolymer micelles and enhanced tumour suppression in vivo

Zhao Lichun,Sun Dandan,Lu Haibin,Han Bing,Zhang Guangyuan,Guan Qingxiang

ObjectivesA system of stearic acid (SA)-modified Bletilla striata polysaccharide (BSP) micelles was developed for the targeted delivery of docetaxel (DTX) as a model anticancer drug (DTX-SA-BSP).MethodsParticle size, zeta potential and DTX release in vitro were measured in release media at different pH values. Quantitative cellular uptake, cytotoxicity assay in vitro and antitumour efficacy in vivo were also evaluated. Cell apoptosis was assessed by flow cytometry.Key findingsDTX-SA-BSP copolymer micelles displayed pH-dependent properties in the respects of particle size, zeta potential and in vitro release behaviour ranging from pH 5.0 to pH 7.4. DTX-SA-BSP copolymer micelles showed higher release rate at pH 5.0 than that at pH 6.0 and 7.4. In vitro cytotoxic effect of DTX-SA-BSP copolymer micelles was higher than that of DTX injection. The results of high-performance liquid chromatography determination confirmed that DTX cellular uptake of micelles was enhanced compared with that of DTX injection. Anticancer activity in vivo further confirmed the enhanced tumour targeting and anticancer efficacy of DTX-SA-BSP copolymer micelles.ConclusionsThe above results show that DTX-SA-BSP copolymer micelles have pH sensitivity. SA-BSP copolymers are a promising carrier for delivering hydrophobic anticancer drugs.

Pharmacokinetics and pharmacodynamics of bioactive compounds in Penyanqing preparation in THP-1 inflammatory cells induced by Lipopolysaccharide

Gong Linna,Miao Zhishuo,Zhang Li,Shi Birui,Xiao Zuoqi,Qiu Panzi,Liu Menghua,Zou Wei

Background Penyanqing (PYQ), a traditional Chinese medicine (TCM), has a good clinical efficacy for the treatment of pelvic inflammatory disease (PID). Previously, researches on its anti-inflammatory effect and mechanism in vitro, in silico, and in vivo have been reported by our team. However, the interrelationship between the anti-inflammatory activity and the active compounds in PYQ are not clear. Here, the pharmacokinetics-pharmacodynamics (PK-PD) study was carried out for more proper clinical use.Methods The plasma concentrations of salvianolic acid B (SAB), protocatechualdehyde (PRO), paeoniflorin (PE), astilbin (AST), ferulic acid (FE), and chlorogenic acid (CH) in SD rats after PYQ administration were determined by a selective and rapid HPLC–MS/MS method. In addition, the PK-PD on cell model was used to explore the relationship between the plasma concentration and inflammatory biomarkers (TNF-α, IL-1β).Results The results of this study showed that the six components could reach the peak blood concentration within 0.29 h, indicating the rapid absorption of it. The eliminations of AST, CH, FE, PE, and PRO were relatively fast due to their mean residence times (MRTs) within 3 h, while the elimination of SAB was slower (MRT 5.67 ± 0.66 h). Combined with a THP-1 cell model, there was a significant correlation between inflammatory factors and component plasma concentrations with correlation coefficients in the range of -0.9—-0.746. Correspondingly, the drug-containing plasma obtained at 0.25 h point exhibited the best inhibition effect on production of IL-1β and TNF-α in LPS-induced THP-1 cells.Conclusion The six main components in PYQ could be quickly absorbed, and there was a potential good correlation between their pharmacokinetics and the pharmacodynamics of PYQ.

Silver-loaded nanotubular structures enhanced bactericidal efficiency of antibiotics with synergistic effect in vitro and in vivo

Na Xu,Hao Cheng,Jiangwen Xu,Feng Li,Biao Gao,Zi Li,Chenghao Gao,Kaifu Huo,Jijiang Fu,Wei Xiong

Preparation, in vitro and in vivo evaluation of mPEG-PLGA nanoparticles co-loaded with syringopicroside and hydroxytyrosol

Guan Qingxia,Sun Shuang,Li Xiuyan,Lv Shaowa,Xu Ting,Sun Jialin,Feng Wenjing,Zhang Liang,Li Yongji

This study investigated the therapeutic efficiency of monomethoxy polyethylene glycol-poly(lactic-co-glycolic acid) (mPEG-PLGA) co-loaded with syringopicroside and hydroxytyrosol as a drug with effective targeting and loading capacity as well as persistent circulation in vivo. The nanoparticles were prepared using a nanoprecipitation method with mPEG-PLGA as nano-carrier co-loaded with syringopicroside and hydroxytyrosol (SH-NPs). The parameters like in vivo pharmacokinetics, biodistribution in vivo, fluorescence in vivo endomicroscopy, and cellular uptake of SH-NPs were investigated. Results showed that the total encapsulation efficiency was 32.38 ± 2.76 %. Total drug loading was 12.01 ± 0.42 %, particle size was 91.70 ± 2.11 nm, polydispersity index was 0.22 ± 0.01, and zeta potential was −24.5 ± 1.16 mV for the optimized SH-NPs. The nanoparticle morphology was characterized using transmission electron microscopy, which indicated that the particles of SH-NPs were in uniformity within the nanosize range and of spherical core shell morphology. Drug release followed Higuchi kinetics. Compared with syringopicroside and hydroxytyrosol mixture (SH), SH-NPs produced drug concentrations that persisted for a significantly longer time in plasma following second-order kinetics. The nanoparticles moved gradually into the cell, thereby increasing the quantity. ALT, AST, and MDA levels were significantly lower on exposure to SH-NPs than in controls. SH-NPs could inhibit the proliferation of HepG2.2.15 cells and could be taken up by HepG2.2.15 cells. The results confirmed that syringopicroside and hydroxytyrosol can be loaded simultaneously into mPEG-PLGA nanoparticles. Using mPEG-PLGA as nano-carrier, sustained release, high distribution in the liver, and protective effects against hepatic injury were observed in comparison to SH.

Diverse risk-avoidance behaviors in DISC1 mice are associated with different neuronal firing patterns in BLA neurons

Xinyi Zhou,Qian Xiao,Jie Tu

It is very important to maintain normal levels of risk avoidance in daily life. We found that DISC1-N TM mice, which are a model for mental disorders, had a phenotype marked by a risk-avoidance impairment as measured in an open-field test (OFT). We used optogenetic methods to modulate glutamatergic neurons in the basolateral amygdala (BLA) in an attempt to rescue this risk-avoidance impairment. We found that photostimulation of BLA neurons at 20 Hz modified DISC1-N TM mouse behavior from low risk avoidance to high risk avoidance. We observed following photostimulation that, compared to controls, the number of entries to the center of the open field was lower and less time was spent in the central area. We also found that the time spent immobile was higher during photostimulation compared with WT mice. We also used a lower photostimulation frequency of 5 Hz, which activated BLA glutamatergic neurons and rescued the risk-avoidance impairment in DISC1-N TM mice. Our findings confirm that the BLA participates in diverse risk-avoidance behavior. Our results are also a reminder that differences in neuronal firing patterns within the same pathway may lead to different physiological functions.

Altered Gut Microbiota is Involved in the Anti-Hypertensive Effects of Vitamin C in Spontaneously Hypertensive Rat

Ying Li,Rawya Mohamed Salih Ibrahim,Hong-Li Chi,Tong Xiao,Wen-Jie Xia,Hong-Bao Li,Yu-Ming Kang

Scope Gut dysbiosis and dysregulation of the gut-brain-axis contributes to the pathogenesis of hypertension. Vitamin C (VC) is a common dietary supplement that shows the ability to lower the elevated blood pressure in hypertensive animals. Thus, the hypothesis that the gut microbiota is involved in the anti-hypertensive effect of VC is proposed. Methods and Results The changes of the gut microbiota and pathology in a spontaneously hypertensive rat (SHR) model after daily oral intake of VC in dosage of 200 or 1000 mg kg −1 are examined. After 4 weeks, the elevated blood pressure of SHRs in both VC-treated groups is attenuated. Sequencing of the gut microbiota shows improvement in its diversity and abundance. Bioinformatic analysis suggests restored metabolism and biosynthesis-related functions of the gut, which are confirmed by the improvement of gut pathology and integrity. Analysis of the hypothalamus paraventricular nucleus (PVN), the central pivot of blood pressure regulation, also shows reduced inflammatory responses and oxidative stress. Conclusions The reduced blood pressure, enriched gut microbiota, improved gut pathology and integrity, and reduced inflammatory responses and oxidative stress in the PVN together suggest that the anti-hypertensive effects of VC involve reshaping of gut microbiota composition and function.

Transgenerational Proteome Plasticity in Resilience of a Marine Copepod in Response to Environmentally Relevant Concentrations of Microplastics

Chen Zhang,Chang-Bum Jeong,Jae-Seong Lee,Dazhi Wang,Minghua Wang

Here, we examined the multigenerational effect of microplastics (6-μm polystyrene beads; with different environmentally relevant concentrations of 0.023 and 0.23 mg/L in seawater) on the marine copepod Tigriopus japonicus under two-generation exposure (F0–F1) followed by one-generation recovery (F2) in clean seawater. Also, the seven life-history traits (survival, sex ratio, developmental time of nauplius phase, developmental time to maturation, number of clutches, number of nauplii/clutch, and fecundity) were measured for each generation. Furthermore, to investigate within-generation proteomic response and transgenerational proteome plasticity, proteome profiling was conducted for the F1 and F2 copepods under the control and 0.23 mg/L microplastics treatment. The results showed successful ingestion of microplastics in F0–F1 under both exposure concentrations, while higher concentration (0.23 mg/L) of microplastics resulted in the significant reduction in survival rate, number of nauplii/clutch, and fecundity. However, the affected traits were totally restored in the recovery generation (F2). Proteomic analysis demonstrated that microplastics exposure increased several cellular biosynthesis processes and, in turn, reduced energy storage due to the trade-off, hence compromising survival and reproduction of the treated copepods in F1. Interestingly, the two-generational effect of microplastics in copepods had significant transgenerational proteome plasticity as demonstrated by increased energy metabolism and stress-related defense pathway, which accounts for regaining of the compromised phenotypic traits during recovery (i.e., F2). Overall, this study provides a molecular understanding on the effect of microplastics at a translational level under long-term multigenerational exposure in marine copepods, and also the transgenerational proteome plasticity is likely rendering the robustness of copepods in response to microplastics pollution.

Plasmonic hot electron transfer in anisotropic Pt–Au nanodisks boosts electrochemical reactions in the visible-NIR region

Guanying Chen,Mingjuan Sun,Juan Li,Mingshan Zhu,Zaizhu Lou,Baojun Li

Anisotropic plasmonic metals have attracted significant attention in enhancing the catalytic performance of catalysts due to their broad light-harnessing capabilities and active hot electrons; however, limited investigations have been dedicated towards improving their electrochemical reaction performance in the visible and near infrared (NIR) regions. Herein, anisotropic Pt-edged Au nanodisks (NDs) were synthesized by controlling the preferential loading of Pt and used as catalysts for plasmon-enhanced electrochemical methanol oxidation reactions (MORs) under visible-NIR light irradiation by, and the light-enhanced electric current over the Pt-edged Au NDs was found to be 3-fold higher than that under dark conditions. Wavelength-dependent electric current over the Pt-edged Au NDs for the MOR in the visible-NIR light region demonstrates that the light-induced enhancement of the electric current is due to surface plasmon resonance (SPR) of the Au NDs. Furthermore, plasmonic hot electron transfer was studied by the single-particle photoluminescence images and spectra of Au NDs and Pt–Au NDs, and the dipole surface plasmon resonance (DSPR) mode was proved to be the main channel for hot electron transfer. During the electrochemical reaction under visible-NIR light irradiation, a plasmonic hot electron is transferred to the electrode, and a “hot hole” is left on the surface, boosting the MOR.

Green and ligand-free gold nanoparticles in Padina australis extract for colorimetric detection of Cu2+ in water

Lihua Wu,Gangan Huang,Ting Xie,Anran Zhang,Yunzhi Fu

The green and ligand-free gold nanoparticles (P-AuNPs) from Padina australis extract were easily and quickly prepared. A colorimetric probe based on P-AuNPs was designed for easy and visual detection of Cu 2+ in domestic water with excellent sensitivity. The –OH and –NH 2 in polysaccharides and proteins of Padina australis had played a reduced and protected role for AuNPs and also been easy to complex Cu 2+ because of chelation. The complexed Cu 2+ dragged P-AuNPs closely to aggregation, causing the red sol to turn blue. Also, the UV–vis spectrum was red-shifted, and a new peak developed. The limits of UV–vis detection are as low as 0.43 μM. The absorbance ratio (A 630 /A 520 ) showed an excellent linear relationship with Cu 2+ concentration (R 2 = 0.9926) with a range of 20–60 μM by UV–vis.

Unraveling the NCo coordination mechanism in chitosan‑cobalt complexes: Structural elucidation and in vivo cobalt supplementation effect

Shuai Wang,Shiping Wang,Zhihao Zheng,Zhangkong Wei,Lixia Shi,Xiaoyan Jia,Li Li,Jing Ren,Lei Yang,Yannan Ma,Ji Zhang,Jianping Wu,Junlong Wang

Polysaccharide-metal complexes possess superior properties and exhibit broad applications with significant developmental potential. In this study, we systematically elucidated the coordination model and mechanisms between chitosan and cobalt(II). First, combining DFT calculations and experimental results, a coordination chemical mechanism of CS-Co(II) was revealed that Co(II) ions preferentially accept electrons from the N atoms of -NH 2 to coordinate with CS, forming a twisted octahedron configuration via sp 3 d 2 hybridization. N Co coordination bonds were dominated by ionic bonding, with a small amount of covalency present. In chain features, Co(II) introduction caused slight chitosan chain degradation and compact conformation. Furthermore, lambs supplemented with CS-Co(II) exhibited higher serum Co content and kidney VB 12 levels, and no abnormalities in blood biochemical indexes were observed, indicating CS-Co(II) provide potential applications in animal production. This investigation provided a novel insight for developing polysaccharide-metal complexes as functional nutritional supplements through elucidation of coordination mechanisms.

Pathogenic Mechanism of the KCNQ4 Gene Variant in Hearing Loss and Functional Validation in a Zebrafish Model

Hui Jia,Xiaowen Liu,Hui Chen,Yanli Wang,Min-Xin Guan,Yufen Guo

The KCNQ4 gene is closely associated with autosomal dominant nonsyndromic hearing loss (DFNA2) and encodes a potassium channel crucial for potassium ion circulation in the inner ear. This study identified a novel KCNQ4 variant, c.825G>T (p.Trp275Cys), associated with progressive hereditary hearing loss in a family. In vitro experiments and structural predictions revealed that this mutation did not affect KCNQ4 channel localization, subunit assembly, or pore size. However, the mutation induced longitudinal extension of the channel, reduced protein stability, and impaired potassium ion selectivity, thereby disrupting potassium ion homeostasis in the inner ear and ultimately leading to hearing loss. Zebrafish models further validated the critical role of the kcnq4 gene in inner ear development. We used morpholino to knock down kcnq4 in zebrafish and rescued the phenotype by reintroducing wild-type kcnq4 mRNA. This approach revealed significant changes in otolith morphology, a marked reduction in hair cell numbers, and abnormal motor responses. Additionally, we cloned and completed the coding sequence (CDS) of kcnq4 mRNA from the AB strain of zebrafish, enriching the available database information. Our findings provide new insights into the molecular mechanisms underlying KCNQ4 -related hereditary hearing loss and lay the groundwork for developing precision treatments and early intervention strategies. Graphical The KCNQ4 p.Trp275Cys mutation induces channel elongation, reduces stability, and leads to decreased intracellular potassium levels. KCNQ4-knockdown zebrafish exhibit abnormal otolith development and hair cell loss, confirming its essential role in the auditory system.