Competition and synergy of Arp2/3 and formins in nucleating actin waves.

Actin assembly and dynamics are crucial for maintaining cell structure and changing physiological states. The broad impact of actin on various cellular processes makes it challenging to dissect the specific role of actin regulatory proteins. Using actin waves that propagate on the cortex of mast cells as a model, we discovered that formins (FMNL1 and mDia3) are recruited before the Arp2/3 complex in actin waves. GTPase Cdc42 interactions drive FMNL1 oscillations, with active Cdc42 and the constitutively active mutant of FMNL1 capable of forming waves on the plasma membrane independently of actin waves. Additionally, the delayed recruitment of Arp2/3 antagonizes FMNL1 and active Cdc42. This antagonism is not due to competition for monomeric actin but rather for their common upstream regulator, active Cdc42, whose levels are negatively regulated by Arp2/3 via SHIP1 recruitment. Collectively, our study highlights the complex feedback loops in the dynamic control of the actin cytoskeletal network.

PolyQ-expanded ataxin-2 aggregation impairs cellular processing-body homeostasis via sequestering the RNA helicase DDX6.

Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the pathogenesis of neurodegenerative diseases such as spinocerebellar ataxia type 2 (SCA2). However, the molecular mechanism underlying how Atx2 aggregation contributes to the proteinopathies remains elusive. Here, we investigated the influence of Atx2 aggregation on the assembly and functionality of cellular processing bodies (P-bodies) by using biochemical and fluorescence imaging approaches. We have revealed that polyQ-expanded (PQE) Atx2 sequesters the DEAD-box RNA helicase (DDX6), an essential component of P-bodies, into aggregates or puncta via some RNA sequences. The N-terminal like-Sm (LSm) domain of Atx2 (residues 82-184) and the C-terminal helicase domain of DDX6 are responsible for the interaction and specific sequestration. Moreover, sequestration of DDX6 may aggravate pre-mRNA mis-splicing, and interfere with the assembly of cellular P-bodies, releasing the endoribonuclease MARF1 that promotes mRNA decay and translational repression. Rescuing the DDX6 protein level can recover the assembly and functionality of P-bodies, preventing targeted mRNA from degradation. This study provides a line of evidence for sequestration of the P-body components and impairment of the P-body homeostasis in dysregulating RNA metabolism, which is implicated in the disease pathologies and a potential therapeutic target.

Ataxin-2 sequesters Raptor into aggregates and impairs cellular mTORC1 signaling.

Ataxin-2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ-expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction. Further research indicates that the polyQ tract and the N-terminal region (residues 1-784) of Atx2 are responsible for the specific sequestration. Moreover, this sequestration leads to suppression of the mTORC1 activity as represented by down-regulation of phosphorylated P70S6K, which can be reversed by overexpression of Raptor. As mTORC1 is a key regulator of autophagy, Atx2 aggregation and sequestration also induces autophagy by upregulating LC3-II and reducing phosphorylated ULK1 levels. This study proposes that Atx2 sequesters Raptor into aggregates, thereby impairing cellular mTORC1 signaling and inducing autophagy, and will be beneficial for a better understanding of the pathogenesis of SCA2 and other polyQ diseases.

Design Strategies toward High-Utilization Zinc Anodes for Practical Zinc-Metal Batteries.

Aqueous Zn-metal batteries (AZMBs) hold a promise as the next-generation energy storage devices due to their low cost and high specific energy. However, the actual energy density falls far below the requirements of commercial AZMBs due to the use of excessive Zn as anode and the associated issues including dendritic growth and side reactions. Reducing the N/P ratio (negative capacity/positive capacity) is an effective approach to achieve high energy density. A significant amount of research has been devoted to increasing the cathode loading and specific capacity or tuning the Zn anode utilization to achieve low N/P ratio batteries. Nevertheless, there is currently a lack of comprehensive overview regarding how to enhance the utilization of the Zn anode to balance the cycle life and energy density of AZMBs. In this review, we summarize the challenges faced in achieving high-utilization Zn anodes and elaborate on the modifying strategies for the Zn anode to lower the N/P ratio. The current research status and future prospects for the practical application of high-performance AZMBs are proposed at the end of the review.

Coaggregation of polyglutamine (polyQ) proteins is mediated by polyQ-tract interactions and impairs cellular proteostasis.

Nine polyglutamine (polyQ) proteins have already been identified that are considered to be associated with the pathologies of neurodegenerative disorders called polyQ diseases, but whether these polyQ proteins mutually interact and synergize in proteinopathies remains to be elucidated. In this study, 4 polyQ-containing proteins, androgen receptor (AR), ataxin-7 (Atx7), huntingtin (Htt) and ataxin-3 (Atx3), are used as model molecules to investigate their heterologous coaggregation and consequent impact on cellular proteostasis. Our data indicate that the N-terminal fragment of polyQ-expanded (PQE) Atx7 or Htt can coaggregate with and sequester AR and Atx3 into insoluble aggregates or inclusions through their respective polyQ tracts. In vitro coprecipitation and NMR titration experiments suggest that this specific coaggregation depends on polyQ lengths and is probably mediated by polyQ-tract interactions. Luciferase reporter assay shows that these coaggregation and sequestration effects can deplete the cellular availability of AR and consequently impair its transactivation function. This study provides valid evidence supporting the viewpoint that coaggregation of polyQ proteins is mediated by polyQ-tract interactions and benefits our understanding of the molecular mechanism underlying the accumulation of different polyQ proteins in inclusions and their copathological causes of polyQ diseases.

Flexible Wearable Electronic Fabrics with Dual Functions of Efficient EMI Shielding and Electric Heating for Triboelectric Nanogenerators.

Traditional conductive fabrics are prepared by the synthesis of conductive polymers and the coating modification of metals or carbon black conductive materials. However, the conductive fabrics cause a significant decline in performance after washing or mechanical wear, which limits their application. Moreover, the single function of the traditional conductive fabric is also the reason that limits its wide application. In order to prepare a wearable, stable, high-performance, washable, multifunctional conductive fabric, we have carried out related research. In this work, polydopamine was used as a bonding layer, an adsorption reduction layer, and a protective layer to improve the bonding between silver nanoparticles and carbon nanotubes (CNTs) on the polyester fabric surface so as to prepare a multifunctional conductive fabric with a high-stability "sandwich" structure, in which a Ag-NPS@CNT structure acting as an intermediate conductive layer formed on the inner layer PDA@CNT by electroless silver plating and the outermost layer PDA@CNT coated on the surface of the intermediate conductive layer by the impregnation-drying method. The sheet resistance of an E-Fabric can reach 2.11 Ω/□ due to the uniform and dense conductive path formed by the special structure Ag-NPs@CNT. At a low voltage of 1.5 V, the E-Fabric can reach 117 °C in 50 s and remain stable. The electrical conductivity and current heating properties of the E-Fabric remain good even after multiple washing or bending tests. Due to its stable and outstanding electrical conductivity, the E-Fabric has an electromagnetic shielding efficiency (SET) of 35.3 dB in the X-band (8.2-12.4 GHz). In addition, E-Fabric-based spin-coated poly(methyl methacrylate) or polydimethylsiloxane electrodes exhibit excellent performance in nanogenerators. Through the low-frequency friction of the human body, transient voltages up to 4 V can be generated from a 2 cm × 2 cm electrode sample. The output power of a single generator can reach about 12 nW/cm2. Therefore, an E-Fabric is considered to have great potential in the fields of electric heating, electromagnetic shielding, and smart wearable devices.

Collective dynamics of actin and microtubule and its crosstalk mediated by FHDC1.

The coordination between actin and microtubule network is crucial, yet this remains a challenging problem to dissect and our understanding of the underlying mechanisms remains limited. In this study, we used travelling waves in the cell cortex to characterize the collective dynamics of cytoskeletal networks. Our findings show that Cdc42 and F-BAR-dependent actin waves in mast cells are mainly driven by formin-mediated actin polymerization, with the microtubule-binding formin FH2 domain-containing protein 1 (FHDC1) as an early regulator. Knocking down FHDC1 inhibits actin wave formation, and this inhibition require FHDC1's interaction with both microtubule and actin. The phase of microtubule depolymerization coincides with the nucleation of actin waves and microtubule stabilization inhibit actin waves, leading us to propose that microtubule shrinking and the concurrent release of FHDC1 locally regulate actin nucleation. Lastly, we show that FHDC1 is crucial for multiple cellular processes such as cell division and migration. Our data provided molecular insights into the nucleation mechanisms of actin waves and uncover an antagonistic interplay between microtubule and actin polymerization in their collective dynamics.

A Biocompatible Vibration-Actuated Omni-Droplets Rectifier with Large Volume Range Fabricated by Femtosecond Laser.

High-performance droplet transport is crucial for diverse applications including biomedical detection, chemical micro-reaction, and droplet microfluidics. Despite extensive progress, traditional passive and active strategies are restricted to limited liquid types, small droplet volume ranges, and poor biocompatibilities. Moreover, more challenges occur for biological fluids due to large viscosity and low surface tension. Here, a vibration-actuated omni-droplets rectifier (VAODR) consisting of slippery ratchet arrays fabricated by femtosecond laser and vibration platforms is reported. Through the relative competition between the asymmetric adhesive resistance originating from the lubricant meniscus on the VAODR and the periodic inertial driving force originating from isotropic vibration, the fast (up to ≈60 mm s-1 ), programmable, and robust transport of droplets is achieved for a large volume range (0.05-2000 µL, Vmax /Vmin  ≈ 40 000) and in various transport modes including transport of liquid slugs in tubes, programmable and sequential transport, and bidirectional transport. This VAODR is general to a high diversity of biological and medical fluids, and thus can be used for biomedical detection including ABO blood-group tests and anticancer drugs screening. These strategies provide a complementary and promising platform for maneuvering omni-droplets that are fundamental to biomedical applications and other high-throughput omni-droplet operation fields.

[Effects of Wheat Straw-derived Biochar Application on Soil Carbon Content Under Different Tillage Practices].

This study intended to examine the influence of biochar application on soil carbon content under different tillage conditions. For this, an indoor incubation experiment was performed with treatments included wheat straw-derived biochar application (0, 5, and 20 g·kg-1) and soil with different tillage measures (ploughing and no-tillage). The effects of biochar addition on soil organic carbon (SOC), dissolved organic carbon (DOC), soil microbial biomass carbon (MBC), readily oxidized organic carbon (ROC), soil inorganic carbon (SIC), pH, water soluble calcium and magnesium, and soil CO2 emissions were analyzed. The results showed that:① Compared with the control, the contents of SOC, ROC, DOC, and water soluble Ca and Mg increased by 20.3%-105.6%, 0.5%-36.0%, 0.8%-30.5%, 3.5%-42.3%, and 2.4%-75.2% in the no-tillage treatments, respectively; and the contents of SOC, ROC, DOC, water-soluble Ca and Mg increased by 29.2%-145.1%, 1.3%-63.9%, 2.4%-55.6%, 18.2%-89.8%, and 10.1%-150.5% in the ploughing treatment, respectively, under different dosage biochar amendments, and was enhanced with an increase in the biochar application amount. Cumulative CO2 emissions were highest with biochar amendment at 5 g·kg-1 under the no-tillage soil condition; however, this increased with an increase in the biochar amount in the ploughing treatment. At the end of incubation experiment, the soil MBC content increased by 35.5%-45.7% compared with the control treatment; however, there was no significant effect on soil pH and SIC between the treatments. ② Compared with the ploughing treatment, the cumulative CO2 emissions, SOC, ROC, DOC, MBC, and water-soluble Ca and Mg contents of the no tillage treatment increased by 34.2%-79.0%, 8.9%-45.5%, 28.2%-73.9%, 40.4%-78.4%, 0.2%-131.7%, 8.7%-39.8%, and 0.3%-61.0%, respectively, while soil pH and SIC decreased by 0.08-0.17 unit and 2.4%-13.9%, respectively, under the same biochar amendment treatments. Overall, the addition of biochar significantly increased soil organic carbon, active organic carbon, soil water soluble calcium and magnesium content, and soil cumulative CO2 emissions, but no significant effect was observed on soil inorganic carbon content.

MTR4 drives liver tumorigenesis by promoting cancer metabolic switch through alternative splicing.

The metabolic switch from oxidative phosphorylation to glycolysis is required for tumorigenesis in order to provide cancer cells with energy and substrates of biosynthesis. Therefore, it is important to elucidate mechanisms controlling the cancer metabolic switch. MTR4 is a RNA helicase associated with a nuclear exosome that plays key roles in RNA processing and surveillance. We demonstrate that MTR4 is frequently overexpressed in hepatocellular carcinoma (HCC) and is an independent diagnostic marker predicting the poor prognosis of HCC patients. MTR4 drives cancer metabolism by ensuring correct alternative splicing of pre-mRNAs of critical glycolytic genes such as GLUT1 and PKM2. c-Myc binds to the promoter of the MTR4 gene and is important for MTR4 expression in HCC cells, indicating that MTR4 is a mediator of the functions of c-Myc in cancer metabolism. These findings reveal important roles of MTR4 in the cancer metabolic switch and present MTR4 as a promising therapeutic target for treating HCC.

Foot-and-mouth disease virus induces lysosomal degradation of NME1 to impair p53-regulated interferon-inducible antiviral genes expression.

Nucleoside diphosphate kinase 1 (NME1) is well-known as a tumor suppressor that regulates p53 function to prevent cancer metastasis and progression. However, the role of NME1 in virus-infected cells remains unknown. Here, we showed that NME1 suppresses viral replication in foot-and-mouth disease virus (FMDV)-infected cells. NME1-enhanced p53-mediated transcriptional activity and induction of interferon-inducible antiviral genes expression. FMDV infection decreased NME1 protein expression. The 2B and VP4 proteins were identified as the viral factors that induced reduction of NME1. FMDV 2B protein has a suppressive effect on host protein expression. We measured, for the first time, VP4-induced lysosomal degradation of host protein; VP4-induced degradation of NME1 through the macroautophagy pathway, and impaired p53-mediated signaling. p53 plays significant roles in antiviral innate immunity by inducing several interferon-inducible antiviral genes expression, such as, ISG20, IRF9, RIG-I, and ISG15. VP4 promoted interaction of p53 with murine double minute 2 (MDM2) through downregulation of NME1 resulting in destabilization of p53. Therefore, 5-flurouracil-induced upregulation of ISG20, IRF9, RIG-I, and ISG15 were suppressed by VP4. VP4-induced reduction of NME1 was not related to the well-characterized blocking effect of FMDV on cellular translation, and no direct interaction was detected between NME1 and VP4. The 15-30 and 75-85 regions of VP4 were determined to be crucial for VP4-induced reduction of NME1. Deletion of these VP4 regions also inhibited the suppressive effect of VP4 on NME1-enhanced p53 signaling. In conclusion, these data suggest an antiviral role of NME1 by regulation of p53-mediated antiviral innate immunity in virus-infected cells, and reveal an antagonistic mechanism of FMDV that is mediated by VP4 to block host innate immune antiviral response.

Adenylyl cyclase 1 as a major isoform to generate cAMP signaling for apoA-1-mediated cholesterol efflux pathway.

HDL apoA-1-mediated cholesterol efflux pathway requires multiple cellular proteins and signal transduction processes, including adenylyl cyclase (AC)/cAMP signaling. Due to the existence of multiple transmembrane AC isoforms, it was not known how many AC isoforms are expressed and which ones are essential for cholesterol efflux in macrophage foam cells. These questions were investigated in THP-1 macrophages in this study. Quantitative RT-PCR detected mRNAs for all nine transmembrane AC isoforms, but only the mRNA and protein of the AC1 isoform were consistently upregulated by cholesterol loading and apoA-1. AC1 shRNA interference decreased AC1 mRNA and protein levels, resulting in reduction of apoA-1-mediated cAMP production and cholesterol efflux, while the intracellular cholesterol levels remained high. Confocal microscopy showed that apoA-1 promoted translocation of cholesterol and formation of cholesterol-apoA-1 complexes (protrusions) on the cholesterol-loaded macrophage surface. AC1 shRNA-interfered macrophages showed no translocation of cholesterol to the cell surface. AC1 shRNA interference also disrupted cellular localization of the intracellular cholesterol indicator protein adipophillin, and the expression as well as surface translocation of ABCA1. Together, our results show that AC1 is a major isoform for apoA-1-activated cAMP signaling to promote cholesterol transport and exocytosis to the surface of THP-1 macrophage foam cells.

Bird diversity in northern Myanmar and conservation implications.

We conducted four bird biodiversity surveys in the Putao area of northern Myanmar from 2015 to 2017. Combined with anecdotal information collected between 2012 and 2015, we recorded 319 bird species, including two species (Arborophila mandellii and Lanius sphenocercus) previously unrecorded in Myanmar. Bulbuls (Pycnonotidae), babblers (Timaliidae), pigeons and doves (Columbidae), and pheasants and partridges (Phasianidae) were the most abundant groups of birds recorded. Species richness below 1 500 m a. s. l. was higher than species richness at higher elevations. Our results suggest that the current protected areas in this region should be expanded to lower elevations to cover critical conservation gaps.

[Expression of Wnt5b in patients with HBV-related hepatocellular carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression of Wnt5b in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) tissues and its correlation with the clinicopathological parameters. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical staining were employed to measure Wnt5b mRNA and protein expressions in two groups of HBV-related HCC patients (100 cases in each) selected from a cohort of 289 cases with HBV-related HCC using simple random sampling method. The correlation of Wnt5b expression with the clinicopathological parameters and the prognosis of HCC patients was analyzed. RESULTS: Wnt5b mRNA expression was significantly higher in HCC tissues than that of adjacent noncancerous tissues in 65.0% (65/100) of the cases, and the positivity rate of Wnt5b protein was significantly higher in HCC tissues than that of adjacent noncancerous tissues (58.0% vs 22.0%, P<0.05). Wnt5b expression was significantly correlated with the tumor size (P<0.05), tumor number (P<0.01, only at the protein level), tumor differentiation (P<0.01, only at the protein level), TNM stage (P<0.05), BCLC stage (P<0.05), metastasis (P<0.05) and recurrence (P<0.01). The patients with up-regulated Wnt5b mRNA and protein had a shorter relapse-free survival (P<0.01). CONCLUSION: s Up-regulated Wnt5b might contribute to the progression of HBV-related HCC and predicts a poor prognosis.

Loss of tumor suppressor miR-126 contributes to the development of hepatitis B virus-related hepatocellular carcinoma metastasis through the upregulation of ADAM9.

Hepatocellular carcinoma is the most common histological type of primary liver cancer, which represents the second leading cause of cancer-related mortality. MiR-126 was reported to be downregulated in hepatocellular carcinoma tissues, compared with its levels in noncancerous tissues. However, baseline miR-126 expression levels in hepatitis B virus-related hepatocellular carcinoma patients who did not undergo pre-operational treatment remains unknown since hepatitis B virus infection and pre-operational transcatheter arterial chemoembolization were shown to upregulate miR-126 expression. Here, we demonstrated that miR-126 is generally downregulated in a homogeneous population of pre-operational treatment-naïve hepatitis B virus-related hepatocellular carcinoma patients (84.0%, 84/100), and its expression is significantly associated with pre-operational alpha-fetoprotein levels ( p < 0.05), microvascular invasion ( p < 0.05), tumor metastasis ( p < 0.05), as well as early recurrence (12 months after surgery; p < 0.01). Furthermore, the results of our study revealed that miR-126 is negatively correlated with ADAM9 expression in hepatitis B virus-related hepatocellular carcinoma patients. Overexpression of miR-126 was shown to attenuate ADAM9 expression in hepatocellular carcinoma cells, which subsequently inhibits cell migration and invasion in vitro. In addition, Cox proportional hazards regression model analysis showed that ADAM9 levels, tumor number, microvascular invasion, and tumor metastasis rate represent independent prognostic factors for shorter recurrence-free survival. In conclusion, we demonstrated that the loss of tumor suppressor miR-126 in hepatitis B virus-related hepatocellular carcinoma cells contributes to the development of metastases through the upregulated expression of its target gene, ADAM9. MiR-126-ADAM9 pathway-based therapeutic targeting may represent a novel approach for the inhibition of hepatitis B virus-related hepatocellular carcinoma metastases.

The transport mechanism of monocarboxylate transporter on spinosin in Caco-2 cells.

OBJECTIVES: The aim of this study was to determine the uptake mechanism of spinosin (SPI) by the monocarboxylic acid transporters (MCTs) in Caco-2 cells. METHODS: The Caco-2 cells were pretreated with various monocarboxylic acids, and the uptake of spinosin from Caco-2 cells was measured by High Performance Liquid Chromatography (HPLC). KEY FINDINGS: Preloading of various monocarboxylic acids enhanced the uptake of SPI, especially salicylic acid (a substrate of MCTs) had a 23.4 times increase in SPI uptake, indicating that the monocarboxylic acid transporters had an efflux effect on SPI uptake and salicylic acid had a strong inhibition on SPI efflux in Caco-2 cells. At the same time, the uptake of SPI through Caco-2 cells was Na(+)- and temperature-dependent, pretreatment without Na(+) significantly increased the uptake of SPI by 1.85 times and incubated at low temperature (4 °C) SPI uptake increased 20% than that of 37 °C. Furthermore, SPI was transported mainly via a carrier-mediated transport: [Vmax = 5.364 µg/mg protein, Km = 657.0 µg/mL]. CONCLUSION: The uptake of spinosin (SPI) in Caco-2 cells was mainly regulated by the monocarboxylic acid transporters along with Salicylic acid.

[Clinical application characteristics of Danggui-Chuanxiong herb pair in Chinese medicines on basis of real-world].

To analyze the clinical application characteristics of Danggui-Chuanxiong(DG-CX) herb pair in Chinese medicines on basis of real-world, and provide reference for explaining the inherent compatibility regularity and the relationship between clinical applications and disease species. From April 1, 2014 to June 30, 2014, a total of 8 792 prescriptions with both "DG"and "CX" in a large third-grade class-A traditional Chinese medicine(TCM) hospital were selected to establish the database for analyzing the ratio, dosage, and corresponding disease species of DG-CX herb pair. The results showed that, "DG-CX" with ratio "1∶1" had the highest frequency in clinical application(42.4%); the dosage was mainly of 15 g for both DG and CX; the disease species were mainly of encephalopathy and pulmonary diseases. "DG-CX" herb pairs with a ratio greater than "1∶1" accounted for 33.3% of all the prescriptions, and the ratio "3∶2" appeared to be most frequent among them; the dosage was mainly of 15 g for DG and and 10 g for CX; the disease species were mainly of encephalopathy diseases. "DG-CX" herb pairs with a ratio less than "1∶1" accounted for 24.3% of all the prescriptions, and the ratio "2∶3" appeared to be most frequent among them; the dosage was mainly of 10 g for DG and 15 g for CX; the disease species were mainly of encephalopathy diseases. Statistical method was applied to study the compatibility and application characteristics of Chinese herb pairs in clinical prescriptions, effectively discover the medication regularity, provide theoretical basis for clinical herbal prescriptions and provide scientific guidance and reliable data for modern research of Chinese herb pairs.

[Full-length genome analysis of four genotype 3 letogenic Newcastle disease viruses isolated from different hosts].

The purpose of this study is trying to analysis the homology between four lentogenic Class I genotype 3 Newcastle disease virus isolates from different hosts with NDV strain NDV 08-004, which was the first obtained complete genome sequence virus of class I genotype 3. The full-length genome of NDV isolates, JS/3/09/Ch, ZJ/3/10/Ch, AH/2/10/Du and JS/9/08/Go,were determined by RT-PCR and then an alyzed. All the genomes are 15 198 nucleotides (nt) in length. Compared with the full genome sequences of Class II NDV stains (genotype IV-IX),four isolates has a 6-nt deletion in the non-coding region of nuclear phosphoprotein gene between nucleotides 1 640-1 641 and 12-nt insertion in the coding region of phospho protein gene between nucleotides 2 381-2 382. All the isolates have the motifs 112EQ/RQE/GRL117 at the cleavage site of the fusion protein, which is typical of lenogenic NDV strains, and it is in agreement with the result of pathogenic tests. The full-length genome of 4 genotype 3 NDV isolates shared 93% nucleotide identity with NDV08-004. The results of alignment of 6 viral genes showed that NP gene shared the highest identity (98.3%-96.4%) and P gene shared the lowest identity (96.1%-91.9%). The results show the following two points. First, it is concluded that the isolates from different hosts share the same genotype has the insignificant divergence in the genetic information. Second, it is proposed that the mutation rates of NP/F/L genes are lower than P/M/HN genes.

Evaluation of impact of Herba Erigerontis injection, a Chinese herbal prescription, on rat hepatic cytochrome P450 enzymes by cocktail probe drugs.

ETHNOPHARMACOLOGICAL RELEVANCE: Herba Erigerontis injection (HEI), one of the most popular herbal prescription in China, is made from the aqueous extracts of Erigeron breviscapus whole plant. Now HEI is widely used for the treatment of cardiovascular diseases and cerebrovascular diseases such as coronary heart disease, anginapectoris and paralysis. AIM OF THE STUDY: The purpose of this study was to investigate the in vivo effect of HEI on rat cytochrome P450 enzymes (CYP1A2, CYP2C11, CYP2D4, CYP2E1 and CYP3A2) to assess its safety through its potential to interact with co-administered drugs. MATERIALS AND METHODS: Rats were randomly divided into five groups. Rats were intravenous administrated with HEI via the caudal vein at the dosage of 1.8ml/kg or 7.2ml/kg once daily for consecutive 3 days or 14 days. On the fourth or the fifteenth day, a cocktail solution at a dose of 5ml/kg, which contained caffeine (2.5mg/kg), tolbutamide (2.5mg/kg), chlorzoxazone (5mg/kg), midazolam (5mg/kg) and metoprolol (10mg/kg), was injected via the lingual vein to all rats. Then 0.8ml blood samples were collected at a set of time-points. The plasma concentrations of probe drugs were simultaneously determined by HPLC. Pharmacokinetic parameters simulated by DAS software were used for the evaluation of HEI on the activities of rat CYP1A2, CYP2C11, CYP2D4, CYP2E1 and CYP3A2 enzymes. ANOVA and Dunnett's test was used for data analysis. RESULTS: There were no significant influence of pharmacokinetic parameters of caffeine, tolbutamide and chlorzoxazone in HEI pretreated rats. But many pharmacokinetic parameters of metoprolol and midazolam in HEI pretreated rats were affected significantly (P<0.05), which indicated that metabolism of metoprolol and midazolam in these treatment groups was evidently slowed down. CONCLUSIONS: The results from the present in vivo study suggested that HEI showed no effects on rat CYP1A2, CYP2C11 and CYP2E1, however, it demonstrated potential inhibitory effects on rat CYP2D4 and CYP3A2. Therefore, caution is needed when HEI is co-administered with drugs metabolized by human CYP2D6 or CYP3A4 in clinic, which may result in increased concentrations of these drugs and relevant herb-drug interactions.

Inhibitory effects of limonin on six human cytochrome P450 enzymes and P-glycoprotein in vitro.

Among the various possible causes for drug interactions, pharmacokinetic factors such as inhibition of drug-metabolizing enzymes and transporters, especially cytochrome P450 (CYP) isoenzymes and P-glycoprotein (P-gp), are regarded as the most frequent and clinically important. Limonin is a widely used dietary supplement and one of the most prevalent citrus limonoids, which are known to have inhibitory effects on CYPs and P-gp. In this study, the in vitro inhibitory effects of limonin on the major human CYP isoenzymes (CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4) activities in human liver microsomes were examined using liquid chromatography-tandem mass spectrometry. The inhibitory effects of limonin on P-gp activity in a human metastatic malignant melanoma cell line WM-266-4 were examined using a calcein-AM fluorometry screening assay. It demonstrates that limonin has negligible inhibitory effects on human CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and P-gp. However, potent inhibition of CYP3A4 by limonin is observed with IC50 values of 6.20 µM (CYP3A4/testosterone) and 19.10 µM (CYP3A4/midazolam). This finding has important implications with regard to food-drug interactions between limonin and several narrow therapeutic index drugs that are metabolized by CYP3A4.