[Highly sensitive detection of fluorescent whitening agents in flour using sheathless capillary electrophoresis-electrospray ionization-tandem mass spectrometry].

Fluorescent whitening agents (FWAs) are dyes that emit visible blue or blue-purple fluorescence upon ultraviolet-light absorption. Taking advantage of light complementarity, FWAs can compensate for the yellow color of many substances to achieve a whitening effect; thus, they are used extensively in various applications. FWAs are generally stable, but their presence in the environment can lead to pollution and accumulation in the body through the food chain. Recent studies have revealed that some types of FWAs, such as coumarin-based FWAs, may exhibit photo-induced mutagenic effects that can trigger allergic reactions in humans and even pose carcinogenic risks. Hence, the development of an accurate and highly sensitive method for detecting FWAs in food-related samples is a crucial endeavor. Owing to the high polarity and structural similarity of FWAs, the accurate determination of these substances in complex food samples requires an analytical method that offers both efficient separation and sensitive detection. Capillary electrophoresis (CE) exhibits essential features such as high separation efficiency, short analysis times, very small sample injection requirements, minimal use of organic solvents, and simple operation. Thus, it is often used as an effective alternative to liquid chromatographic techniques. Over the past few decades, electrospray ionization mass spectrometry (ESI-MS) has been utilized as a highly sensitive and accurate detection method in numerous chemical analytical fields because it enables the analysis of molecular structures. By combining the high separation efficiency of CE with the high sensitivity of ESI-MS, a powerful tool for identifying and quantifying trace amounts of FWAs in food samples may be obtained. In this study, we present a method based on sheathless CE coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS) for the simultaneous detection of six trace FWAs in flour. In the proposed method, the CE separation device is directly coupled to the mass spectrometer through a sheathless interface without the need for a sheath liquid for electric contact, thereby avoiding the dilution of the analytes and improving detection sensitivity. Various conditions that could affect extraction recovery, separation efficiency, and detection sensitivity were evaluated and optimized. The FWAs were effectively extracted from the sample matrix with reduced matrix effects by ultrasonic-assisted extraction at a temperature of 30 ℃ for 20 min using CHCl3-MeOH (3∶2, v/v) as the extraction solvent. The extract was centrifuged, dried under N2, and reconstituted in CHCl3-MeOH (1∶4, v/v) for subsequent analysis. During the detection process, the CE device was coupled to the ESI-MS/MS instrument via a highly sensitive porous spray needle, which served as the sheathless electrospray interface. The target FWAs were scanned in positive-ion mode (ESI+) to ensure the stability and intensity of the obtained signals. Additionally, multiple-reaction monitoring (MRM) mode and MS/MS analysis were used to simultaneously quantify the six targets with high selectivity. The developed sheathless CE-ESI-MS/MS method detected the FWAs with high sensitivity over wide linear ranges with low method limits of detection (0.04-0.67 ng/g). The recoveries of the six target FWAs at three spiked levels were between 77.5% and 97.2%, with good interday (RSD≤11.5%) and intraday (RSD≤10.2%) precision. Analyses of the six target FWAs in eight commercial flour samples were performed using this method, and four positive samples were identified. These results demonstrate that the proposed CE-ESI-MS/MS method is a promising strategy for the determination of trace FWAs in complex food sample matrices with efficient separation and high sensitivity.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of TG103 injection in participants who are overweight or obese: a randomized, double-blind, placebo-controlled, multiple-dose phase 1b study.

BACKGROUND: TG103, a glucagon-like peptide-1 analog, is being investigated as an option for weight management. We aimed to determine the safety, tolerability, pharmacokinetics, and pharmacodynamics of TG103 injection in participants who are overweight or obese without diabetes. METHODS: In this randomized, double-blind, placebo-controlled, multiple-dose phase 1b study, participants aged 18-75 years with a body-mass index (BMI) ≥ 26.0 kg/m2 and body weight ≥ 60 kg were enrolled from three centers in China. The study included three cohorts, and in each cohort, eligible participants were randomly assigned (3:1) to one of three once-weekly subcutaneous TG103 groups (15.0, 22.5 and 30.0 mg) or matched placebo, without lifestyle interventions. In each cohort, the doses of TG103 were escalated in 1-week intervals to the desired dose over 1 to 4 weeks. Then participants were treated at the target dose until week 12 and then followed up for 2 weeks. The primary endpoint was safety and tolerability assessed by the incidence and severity of adverse events (AEs) from baseline to the end of the follow-up period. Secondary endpoints included pharmacokinetic and pharmacodynamic profiles of TG103 and the occurrence of anti-drug antibodies to TG103. RESULTS: A total of 147 participants were screened, and 48 participants were randomly assigned to TG103 (15.0, 22.5 and 30.0 mg groups, n = 12 per group) or placebo (n = 12). The mean (standard deviation, SD) age of the participants was 33.9 (10.0) years; the mean bodyweight was 81.65 (10.50) kg, and the mean BMI was 29.8 (2.5) kg/m2. A total of 466 AEs occurred in 45 of the 48 participants, with 35 (97.2%) in the TG103 group and 10 (83.3%) in the pooled placebo group. Most AEs were grade 1 or 2 in severity, and there were no serious adverse events (SAEs), AEs leading to death, or AEs leading to discontinuation of treatment. The steady-state exposure of TG103 increased with increasing dose and was proportional to Cmax,ss, AUCss, AUC0-t and AUC0-inf. The mean values of Cmax,ss ranged from 951 to 1690 ng/mL, AUC0-t ranged from 150 to 321 µg*h/mL, and AUC0-inf ranged from 159 to 340 µg*h/mL. TG103 had a half-life of 110-116 h, with a median Tmax of 36-48 h. After treatment for 12 weeks, the mean (SD) values of weight loss from baseline in the TG103 15.0 mg, 22.5 mg and 30.0 mg groups were 5.65 (3.30) kg, 5.35 (3.39) kg and 5.13 (2.56) kg, respectively, and that in the placebo group was 1.37 (2.13) kg. The least square mean percent weight loss from baseline to D85 in all the TG103 groups was more than 5% with p < 0.05 for all comparisons with placebo. CONCLUSIONS: In this trial, all three doses of once-weekly TG103 were well tolerated with an acceptable safety profile. TG103 demonstrated preliminary 12-week body weight loss without lifestyle interventions, thus showing great potential for the treatment of overweight and obesity. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04855292. Registered on April 22, 2021.

Arterial embolization in the treatment of multiple renal and hepatic hamartomas with spontaneous hemorrhage and 2-year follow-up: a case report.

BACKGROUND: Hamartoma is a common benign tumor that usually occurs in the kidney, liver, lung, and pancreas. Large renal hamartomas may spontaneously rupture and hemorrhage, which is potentially life-threatening. CASE PRESENTATION: This report describes a 46-year-old Han Chinese female patient with multiple renal and hepatic hamartomas with rupture and hemorrhage of giant hamartoma in the left kidney. She underwent arterial embolization three times successively, and her condition was stable during the 2-year follow-up. This report includes a review of the relevant literature CONCLUSIONS: the findings in this report and previous literature suggest that arterial embolization can not only rapidly treat hamartoma hemorrhage in the acute phase but can also effectively control multiple lesions in the long term after repeated multisite arterial embolization.

Hydroxyl silicone oil grafting onto a rough thermoplastic polyurethane surface created durable super-hydrophobicity.

Indwelling medical catheters are frequently utilized in medical procedures, but they are highly susceptible to infection, posing a vital challenge for both health workers and patients. In this study, the superhydrophobic micro-nanostructure surface was constructed on the surface of thermoplastic polyurethane (TPU) membrane using heavy calcium carbonate (CaCO3) template. To decrease the surface free energy, hydroxyl silicone oil was grafted onto the surface, forming a super-hydrophobic surface. The water contact angle (WCA) increased from 91.1° to 143 ± 3° when the concentration of heavy calcium CaCO3 was 20% (weight-to-volume (w/v)). However, the increased WCA was unstable and tended to decrease over time. After grafting hydroxyl silicone oil, the WCA rose to 152.05 ± 1.62° and remained consistently high for a period of 30 min. Attenuated total reflection infrared spectroscopy (ATR-FTIR) analysis revealed a chemical crosslinking between silicone oil and the surface of TPU. Furthermore, Scanning electron microscope (SEM) image showed the presence of numerous nanoparticles on the micro surface. Atomic force microscope (AFM) testing indicated a significant improvement in surface roughness. This method of creating a hydrophobic surface demonstrated several advantages, including resistance to cell, bacterial, protein, and platelet adhesion and good biosecurity. Therefore, it holds promising potential for application in the development of TPU-based medical catheters with antibacterial properties.

Paper-based chiral biosensors using enzyme encapsulation in hydrogel network for point-of-care detection of lactate enantiomers.

Chiral analysis is of pivotal importance in a variety of fields due to the different biological activities and functions of enantiomers. Here, we develop a simple paper-based chiral biosensor that can perform sample-to-answer simultaneous analysis of lactate enantiomers in human serum samples. By modification of alginate hydrogel with "egg-box" three-dimensional network structure on a glass microfiber paper, reagents of enantiomer-selective enzymatic reactions are efficiently encapsulated forming the sensing regions for chiral analysis. Dual enzyme catalytic system (lactate dehydrogenase and glutamic pyruvic transaminase) is utilized to enhance the response of the biosensor. A smartphone with color analysis software is used to collect and analyze the fluorescence signal from the product nicotinamide adenine dinucleotide. The results show that the sensor has excellent selectivity toward lactate enantiomers with low limit-of-detection of (30.0 ± 0.7) µM for L-lactate and (3.0 ± 0.2) µM for D-lactate, and wide linear detection range of 0.1-3.0mM and 0.01-0.5 mM for L-lactate and D-lactate respectively. The proposed method is successfully applied to the simultaneous detection of L-/D-lactate concentrations in human serum with satisfactory accuracy. Our study provides a robust approach for developing chiral biosensors, which would have promising application prospect in point-of-care testing (POCT) analysis of various biological and food samples.

A comparative metabolomics study between grain-sized moxibustion and suspended moxibustion on rats with gastric ulcers.

Grain-sized moxibustion (GS-Moxi) and suspended moxibustion (S-Moxi) represent the two typical local heat therapies in Traditional Chinese Medicine (TCM) and have been extensively used in treating gastric ulcers (GU) in China. However, the difference in biological response between the two moxibustion therapies in treating GU remains unclear. Here we investigated the therapeutic effect and potential mechanistic difference underlying the two moxibustion methods. Ethanol-induced GU model was established and was treated with GS-Moxi or S-Moxi at ST36 and ST21 for 5 days separately. And then, gastric histopathological examination, immunohistochemical staining for repair factors (EGFR, VEGF, Ki67), and 1H NMR-based metabolomics analysis of plasma and stomach of rats were conducted. We found GS-Moxi and S-Moxi effectively alleviated gastric damage and significantly increased the expression of related repair factors. However, S-Moxi corrected aberrant energy metabolism and lipids metabolism in GU rats but had little effect on neurotransmitter-related metabolism, while GS-Moxi regulated energy metabolism and neurotransmitter-related metabolism in GU rats but had no effect on lipids metabolism. We further proposed that the main target of S-Moxi may be liver and vasculature, whereas GS-Moxi specially targeted the stomach via regulating nervous system. This study strongly verified the outstanding gastroprotective effects of moxibustion and enriched our understanding of the varied biological responses triggered by different moxibustion methods.

Dual-mode DNA walker-based optical fiber biosensor for ultrasensitive detection of microRNAs.

We present a novel dual-mode DNA-walker based optical fiber biosensor (DMDW-Opt biosensor) for sensitive assay of micro-RNAs in bio-samples. In the sensor system, we develop a new strategy for the cascade amplification, DNA-walker/rolling cycle amplification (RCA), by the use of the residue track of the walker. The strategy can significantly improve the response of the sensor and avoid any tedious operation procedure. Dual-mode readouts, i.e., fluorescence and chemiluminescence, are measured independently without interfering with each other to achieve reliable and accurate analysis. Optical fibers with the surface modified by gold nanoparticles are utilized as the support for fabrication of the sensor, which would be benefit for developing miniaturized and portable sensing devices. The performance of the proposed method is evaluated by using micro-RNAs (MiR-155 and MiR-21) as the analytical target. The method is successfully applied for accurate determination of micoRNAs in human serum and MCF-7 cells. Our method can perform sensitive assays of MiR-155 with limit-of-detection as low as 97.72 fM and 11.22 fM, MiR-21 with limit-of-detection as low as 107.15 fM and 8.32 fM for the fluorescence- and the chemiluminescence-readout respectively, and the biosensor exhibits excellent specificity, reproducibility and storage stability, indicating its valuable potential applications for sensing trace-amount targets in complicated real samples.

Serotonin acts through YAP to promote cell proliferation: mechanism and implication in colorectal cancer progression.

Serotonin, also known as 5-hydroxytryptamine (5-HT), is a key messenger that mediates several central and peripheral functions in the human body. Emerging evidence indicates that serotonin is critical in tumorigenesis, but its role in colorectal cancer remains elusive. Herein, we report that serotonin transporter (SERT) transports serotonin into colorectal cancer cells, enhancing Yes-associated protein (YAP) expression and promoting in vitro and in vivo colon cancer cell growth. Once within the cells, transglutaminase 2 (TG2) mediates RhoA serotonylated and activates RhoA-ROCK1/2 signalling to upregulate YAP expression in SW480 and SW1116 cells. Blocking SERT with citalopram reversed the serotonin-induced YAP expression and cell proliferation, inhibiting serotonin's effects on tumour formation in mice. Moreover, SERT expression was correlated with YAP in pathological human colorectal cancer samples and the levels of 5-HT were highly significant in the serum of patients with colorectal cancer. Together, our findings suggested that serotonin enters cells via SERT to activate RhoA/ROCK/YAP signalling to promote colon cancer carcinogenesis. Consequently, targeting serotonin-SERT-YAP axis may be a potential therapeutic strategy for colorectal cancer. Video abstract.

Aptamer affinity-based microextraction in-line coupled to capillary electrophoresis mass spectrometry using a porous layer/nanoparticle -modified open tubular column.

An aptamer affinity based microextraction column is developed to be directly in-line coupled to capillary electrophoresis-mass spectrometry (CE-MS) for analyzing mycotoxins in food samples. Single-stranded DNA aptamers for selective recognition of aflatoxin B1 (AFB1) and ochratoxin A (OTA) targets are co-immobilized via covalent bonds on the surface of the inlet end of a capillary, which is pre-modified with three-dimensional porous layer and gold nanoparticles to enhance the specific surface area and loading capacity. The outlet of the capillary is designed as a porous tip to serve as the spray source for injection to the mass spectrometry. All the necessary processes for pretreatment and analysis of a sample are accomplished in one injection, including aptamer affinity-based microextraction, CE separation and MS detection of analytes. AFB1 and OTA are simultaneously determined in a wide linear range with sample consumption of only 1 µL and the limit-of-detection as low as 1 pg/mL. The microextraction column exhibits excellent repeatability and stability, which can be used over 45 runs within a month with CE separation efficiency and only MS intensity slightly decreased. Mycotoxins in three kinds of cereal based infant foods are accurately analyzed using the proposed method. The study provides a robust and universal approach that would have potential applications in a variety of analytical fields based on selective molecular recognition coupling to CE-MS analysis.

Biological role of long non-coding RNA FTX in cancer progression.

Long non-coding RNAs (LncRNAs) are involved in several types of cancer and participate actively in tumorigenesis and disease progression. LncRNA FTX is the transcription product of the FTX gene located at the X-inactivation center (Xic). LncRNA FTX has been shown to regulate cancer cell proliferation, migration, and aberrant metabolism, as well as increase tumor growth and metastasis in vivo. Herein, we summarized currently available research on the interaction between LncRNA FTX and associated molecules and signaling pathways in malignant tumors to better understand the biological roles of LncRNA FTX in cancer progression.

Capillary-based fluorescence microsensor with polyoxometalates as nanozyme for rapid and ultrasensitive detection of artemisinin.

A novel capillary-based fluorescence microsensor for artemisinin was developed with functional polyoxometalates (POMs) as nanozyme by a layer-by-layer self-assembly strategy. Vanadomolybdophosphoric heteropoly acid (H5PMo10V2O40, PMoV2) and tungstophosphoric heteropoly acid (Na5PW11O39Cu, PW11Cu) with high peroxidase-like activity were synthesized and immobilized on capillary to catalyze artemisinin/thiamine reaction and generate the amplified fluorescence signal. The wide linear range up to 13.0 µM with the low limit of detection of 0.03 µM (S/N = 3) was achieved for the determination of artemisinin by using the proposed POMs-microsensor. The method has been successfully used to detect artemisinin in human plasma and antimalarial drugs with satisfactory accuracy. This work developed a novel capillary fluorescence microsensor with functional POMs as nanozyme, which can serve as a promising candidate in fluorescence microanalysis.

[Nuclear magnetic resonance-based metabolomics revealed metabolite profiles participate in intervention effect of refined moxibustion in gastric ulcer model rats].

OBJECTIVE: To investigate the effect of refined moxibustion on expression of gastric mucosal epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF), and changes of metabolite profiles in gastric ulcer (GU) rats, so as to analyze its mechanism underlying improvement of GU. METHODS: Male SD rats were randomized into control, model, acupoint moxibustion groups (n=6 per group). The GU model was induced by cold-restraint stress. The ignited refined moxa was applied to bilateral "Liangmen" (ST21) and "Zusanli" (ST36) for 3 cones/acupoint, once daily for 7 days. Then, we employed 1H NMR-based metabolomics approach to analyze the metabolic profiles of serum and stomach tissue samples. The conventional histopathological changes of the gastric mucosa were observed by H.E. stain and the expressions of EGFR and VEGF in the gastric mucosa were detected by immunohistochemistry. RESULTS: Compared to the control group, the expression levels of EGFR and VEGF were significantly increased in the model group (P<0.01, P<0.05), and further notably up-regulated in the acupoint moxibustion group (P<0.001, P<0.01). Results of H.E. staining showed damage of the folds of gastric mucosa, disordered arrangement of the glands, infiltration of inflammatory cells and unclear structure of gastric mucosa in the model group, which was relatively milder in the acupoint moxibustion group. 1H-NMR technical analysis showed that in comparison with the control group, 11 and 11 metabolites in the stomach extract and plasma were increased, 10 in the gastric tissue and 3 in the plasma were decreased in the GU model group; while in comparison with the model group, 17 differently expressed metabolites in the gastric extract and 10 metabolites in the plasma restored to their levels of control group after the acupoint moxibustion intervention. These metabolites participate in 12 metabolic pathways including glycine, serine and threonine metabolism, glutathione metabolism, glycine metabolism, alanine, aspartic acid and glutamic acid metabolism, purine metabolism, glyoxylic acid and digarboxylic acid metabolism, biosynthesis of aminoacyl-tRNA, amino sugar and nucleotide sugar metabolism, cysteine and methionine metabolism, citrate cycle, pyruvate metabolism, and the mutual conversion of pentose and glucuronate，suggesting their involvement in moxibustion-induced improvement of GU. CONCLUSION: Refined moxibustion at ST21 and ST36 can up-regulate the expression of EGFR and VEGF in the gastric mucosa and lessen gastric mucosal injury, which may be related to its effects in reducing GU-induced metabolic disorders, including sugar, purine, amino acid, and phospholipid metabolism and antioxidant defense system.

Predicting the potential toxicity of 26 components in Cassiae semen using in silico and in vitro approaches.

Cassiae semen are dried and ripe seeds of Cassia obtusifolia L. or Cassia tora L. (Fabaceae) and have been made into roasted tea or used as a traditional medicine in Asian countries. However, it was reported to result in liver and renal toxicity. The components of Cassiae semen that induce hepatotoxicity or nephrotoxicity remain unknown. In the present study, we evaluate the potential toxicity of 26 newly isolated compounds from Cassiae semen using quantitative structure-activity relationship (QSAR) methods and co-culture of hepatic and renal cell approaches, and we aim to illustrate the relationship between the structural characteristics and cytotoxicity by general linear models (GLMs). Both the QSAR models and co-culture of hepatic and renal cell systems predicted that 6 compounds were potentially hepatotoxic, 10 compounds were potentially nephrotoxic, and specific anthraquinones and anthraquinone-glucosides were potential toxicants in Cassiae semen. Specific groups such as -OH and -OCH3 at the R1, R2, R3, and R7 positions influenced the cytotoxicity.

[Endogenous metabolites involving effects of moxibustion on injured gastric mucosal tissue in rats with stomach heat or cold syndrome based on nuclear magnetic resonance spectroscopy].

OBJECTIVE: To investigate the profile of metabolites of gastric mucosa involving the effectiveness of moxibustion in the treatment of syndromes of stomach heat (SH) and stomach cold (SC) by 1H-nuclear magnetic resonance (1H-NMR) spectroscopy in rats, so as to reveal its mechanisms underlying improvement of gastric disorders. METHODS: Male SD rats were randomly divided into control, SH-model, SC-model, SH-moxibustion and SC-moxibustion groups (n＝6 rats/group). The SH-model and SC-model were established by gavage of pepper liquid plus ethanol, and ice water plus NaOH, respectively. Moxibustion was applied to bilateral "Zusanli" (ST36) and "Liangmen"(ST21) for 20 min, once daily for 7days. Histopathological changes of the gastric tissue were observed by H．E. staining. Differential metabolites in the gastric mucosal tissue were detected and the relevant metabolic pathways analyzed by using 1H-NMR, pattern recognition method，and online MetPA (http: //www.metaboanalyst.ca). RESULTS: Compared with the control group, the body mass was decreased significantly from the 4th to 14th day after modeling (P<0.05，P<0.01). After the treatment, the body mass was obviously increased from the 10th day on in both SH-EA and SC-EA groups relevant to the SH and SC model group, respectively (P<0.05，P<0.01). H．E. staining showed severe damage of the columnar epithelial structure of the gastric mucosa and inflammatory cell infiltration in the SH group, and inflammatory cell infiltration in the SC model group, which were relatively milder in both moxibustion groups. 1H-NMR analysis displayed a total of 16 potential biomarkers in the injured gastric mucosa of SH syndrome and 14 biomarkers for the SC syndrome after mode-ling, and 13 metabolites related to SH moxibustion and 8 metabolites related to SC moxibustion after moxibustion interventions, respectively. After moxibustion, among the 13 differential metabolites of the SH syndrome, the effectively up-regulated candidates were isoleucine, creatinine, choline and lactate (P<0.05), and the down-regulated ones were choline phosphate, glycine, alanine, urine pyrimidine, tyrosine, phenylalanine, hypoxanthine, adenosine and nicotinamide (P<0.05). Among the 8 metabolites related to the SC syndrome, creatinine, ethanolamine, choline, adenosine and nicotinamide were markedly increased (P<0.05), and glycine, creatine phosphate and tyrosine remarkably decreased in their levels after moxibustion (P<0.05). MetPA showed that moxibustion could regulate 10 metabolic pathways for SH syndrome and 7 metabolic pathways for SC syndrome. Metabolites and metabolic pathways are mainly involved in functions of amino acid metabolism, energy metabolism and inflammatory response. CONCLUSION: The idea of "moxibustion could be used for heat syndrome" has metabolic substance basis, and its efficacy in repairing the injured gastric mucosa involves regulation of amino acid metabolism, energy balance and inflammation response, and moxibustion for SH and SC syndromes has both generality and specificity in regulating metabolic activities.

Anchoring copper nanoclusters to Zn-containing hydroxy double salt: construction of 2D surface confinement induced enhanced emission toward bio-enzyme sensing and light-emitting diode fabrication.

Surface CIEE based on Zn-HDS as host material and GSH-CuNCs as guest molecules was developed to produce fluorescence composite GSH-CuNCs/Zn-HDS for the first time. It displays high quantum yield, long fluorescence lifetime and good stability, and was applied to sensitive bioenzyme sensing and fabrication of a high performance light-emitting diode.

Investigation of the surface confinement effect of copper nanoclusters: construction of an ultrasensitive fluorescence turn-on bio-enzyme sensing platform.

Copper nanoclusters (CuNCs) have attracted considerable research interest due to their good physicochemical properties, ease of preparation, and low price. However, the low quantum yield and poor stability in aqueous solutions have greatly limited their applications. In order to improve the fluorescence properties and stability of CuNCs, in this paper, the surface confinement effect of CuNCs based on 2D layered double hydroxide (LDH) was proposed to prepare the fluorescent composites of glutathione protected CuNCs and LDH (GS-CuNCs/LDH) with excellent quantum yield and long fluorescence lifetime. Moreover, a novel, simple, and ultrasensitive fluorescence assay for the detection of hyaluronidase was proposed based on the surface confinement effect. The limit of detection for hyaluronidase was as low as 0.014 U mL-1. For the first time, this work developed a bio-enzyme sensing platform based on the surface confinement effect, which can serve as a promising candidate in biosensing.

Effect of euphorbia factor L1 on oxidative stress, apoptosis, and autophagy in human gastric epithelial cells.

BACKGROUND: Euphorbia factor L1 (EFL1), a lathyrane-type diterpenoid from the medicinal herb Euphorbia lathyris L. (Euphorbiaceae), has been reported for many decades to induce gastric irritation, but the underlying mechanisms remain unclear. PURPOSE: The objective of this study was to investigate EFL1-induced cytotoxicity and the potential mechanisms of action on the human normal gastric epithelial cell GES-1. METHODS: GES-1 cells were treated with EFL1 (12.5-200 µM) for different time intervals, and cell survival, LDH release, intracellular reactive oxygen species (ROS), malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity were detected. Mitochondrial membrane potential (MMP) assay, DAPI staining, DNA fragment assay, and annexin V-FITC/PI staining were performed. The interaction between EFL1 and Bcl-2, cytochrome c, caspase-9, caspase-3, PI3K, AKT, and mTOR proteins was simulated by molecular docking. The mRNA and protein expression of apoptosis and autophagy factors were detected by RT-qPCR and Western blotting. RESULTS: EFL1 decreased survival, increased LDH leakage, and induced abnormal production of ROS, MDA and SOD in GES-1 cells. Mitochondria-mediated apoptosis was characterized by decreased MMP, condensed nuclei, fragmented DNA, and increased apoptosis rate. EFL1 interacted with proteins via hydrogen bonding. The mRNA, total or phosphorylated protein expression of Bcl-2, mitochondrial cytochrome c, PI3K, AKT, mTOR and p62 were downregulated; in contrast, those of cytoplasmic cytochrome c, cleaved caspase-9, cleaved caspase-3, LC3-ll and Beclin-1 were upregulated. CONCLUSION: These findings indicated that EFL1 decreased the survival of GES-1 cells through EFL1-induced oxidative stress, activation of the mitochondria-mediated apoptosis as well as autophagy via inhibition of the PI3K/AKT/mTOR pathway.

Anthraquinones in the aqueous extract of Cassiae semen cause liver injury in rats through lipid metabolism disorder.

BACKGROUND: Cassiae semen has been used as the tea or medicine component to treat hyperlipidemia or for hepatoprotection. However, Cassiae semen was reported to be a potentially hepatotoxic herb, and the underlying hepatotoxicity mechanisms or specific hepatotoxic components of Cassiae semen are unknown. PURPOSE: In this study, we aimed to explore the potential hepatotoxicity mechanisms and the hepatotoxic components of Cassiae semen. METHODS: Both young adult male and female SD rats were orally administrated with the aqueous extract of the seeds of Senna obtusifolia (L.) H.S.Irwin & Barneby at doses of 4.73, 15.75, 47.30 g/kg for 28 days, and the body weight, liver coefficient, bile acids, histopathology, serum levels of TC, TG, LDL, HDL, ALP, ALT, AST, and LDH were examined. Lipidomic analysis of rat serum was performed by LC-MS to investigate the specifically changed lipids caused by the aqueous extract treatment. The components absorbed in plasma were detected by UHPLC-Q-Exactive-MS. MTT assay was used to evaluate the cytotoxicity of these components absorbed in plasma. RESULTS: The serum levels of ALP, AST, ALT, LDH were increased on day 7 with some of which gradually dropped to normal level on day 28. In high dose of the aqueous extract treated group, the histopathological changes were observed based on the cytoplasmic vacuolation in the liver and the increase of bile acids, indicating the hepatotoxicity of the aqueous extract. The changes of TC, TG, LDL, HDL indicated the disorder of lipid metabolism. By comparing the difference in lipids between high dose group and control group, the results showed that the alterations were primarily focused on glycerophospholipid metabolism in both male and female rats. In addition, the glycerolipid metabolism in female rats also changed. Further analyses found that PC (18:2/20:4) and LysoPC 18:0 were significantly increased. Among these phytochemicals detected in plasma, nine components in the aqueous extract were considered to have the highest concentrations, particularly some types of anthraquinones (AQs) existing in Cassiae semen (AQs-in-CS), such as obtusifolin, aurantio-obtusin, and obtusin. The MTT assay showed that emodin, obtusifolin, rhein, aurantio-obtusin, and obtusin inhibited cell viability. Considering plasma concentrations and cytotoxicity of these components, our study indicates that the AQs-in-CS (obtusifolin, aurantio-obtusin and obtusin), emodin and rhein are the potential hepatotoxic phytochemicals in the aqueous extract.

Electrostatically controlled fluorometric assay for differently charged biotargets based on the use of silver/copper bimetallic nanoclusters modified with polyethyleneimine and graphene oxide.

An electrostatically controlled fluorometric assay is described that is based on the use of silver/copper bimetallic nanoclusters. The nanoclusters were coated with polyethyleneimine (PEI-Ag/CuNCs). At pH 7.4, these particles are positively charged. Their blue fluorescence (with excitation/emission peaks at 341/464 nm) depends on local pH values and temperature. If graphene oxide (which is negatively charged at pH 7.4) is introduced, the fluorescence of the PEI-Ag/CuNCs is quenched. Based on various electrostatic interactions, three kinds of biomacromolecules were detected by fluorometry. These include (negatively charged) heparin, (positively charged) protamine, and (virtually uncharged) trypsin. Heparin is detected by using GO/PEI-Ag/CuNCs, protamine by using GO/heparin/PEI-Ag/CuNCs, and trypsin by using GO/protamine/heparin/PEI-Ag/CuNC. The detection limits and linear ranges are 4.8 nM and 10-450 nM for heparin, 0.09 µg·mL-1 and 0.25-5 µg·mL-1 for protamine, and 0.03 µg·mL-1 and 0.05-1 µg·mL-1 for trypsin. Zeta potentials of the various substances in the system were determined to elucidate the detection mechanism. Comceivably, the method provides a widely applicable approach for electrostatically controlled biomolecular assays. Graphical abstract Schematic presentation of electrostatically controlled fluorometric assay for the detection of heparin, protamine, and trypsin based on the silver/copper bimetallic nanoclusters modified with polyethyleneimine and graphene oxide.

[Toxicokinetics of bakuchiol, hepatic and renal toxicity in rats after single oral administration of Psoraleae Fructus and combination with Glycyrrhizae Radix et Rhizoma].

To study the toxicokinetics of bakuchiol, hepatic and renal toxicity in rats after single oral administration of Psoraleae Fructus and combined with Glycyrrhizae Radix et Rhizoma, in order to provide scientific evidences for clinical safe medication use. A total of 35 SD rats were randomly divided into seven groups: vehicle (distilled water) control group, Glycyrrhizae Radix et Rhizoma group, positive control (aristolochic acid A) group, Psoraleae Fructus (40 g x kg(-1)) group( both male and female rats), Psoraleae Fructus and Glycyrrhizae Radix et Rhizoma (40 +20) g x kg(-1) group (both male and female rats). HPLC-UV method was used to determine the concentration of bakuchiol in rat plasma at different time points after single oral administration. Plasma alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), plasma creatinine (Cr), N-acetyl-ß-D-glucosaminidase (NAG) and kidney injury molecule 1 (Kim-1) were measured after administration for 24 h. The main toxicokinetics parameters of bakuchiol in rats exert significantly gender difference. When Psoraleae Fructus combination with Glycyrrhizae Radix et Rhizoma, the total area under the plasma concentration-time curve( AUC), C(max), and plasma clearance (CL) of bakuchiol were increased, respectively; CL, half-life (t½) were decreased, and T(max) were prolonged. The biochemical indicators (including ALT, AST, BUN, Cr and KIM-1 level) in different dose of Psoraleae Fructus groups, were found no statistically significant difference when compared with vehicle control group. The level of NAG in both Psoraleae Fructus and compatibility with Glycyrrhizae Radix et Rhizoma groups were significant increased (P < 0.05). There are obvious effects on toxicokinetics of bakuchiol in rats when Psoraleae Fructus combined with Glycyrrhizae Radix et Rhizoma. Renal toxicity induced by Psoraleae Fructus at high dose was observed after single oral administration and no liver damage in rats was found.