Identification of Q-markers for Cistanches Herba based on HPLC-Q-TOF-MS/MS and network pharmacology / 中国中药杂志

This study aims to establish a method for analyzing the chemical constituents in Cistanches Herba by high performance liquid chromatography(HPLC) and quadrupole-time-of-flight tandem mass spectrometry(HPLC-Q-TOF-MS/MS), and to reveal the pharmacological mechanism based on network pharmacology for mining the quality markers(Q-markers) of Cistanches Herba. The chemical constituents of Cistanche deserticola and C. tubulosa were analyzed via HPLC-Q-TOF-MS/MS. The potential targets and pathways of Cistanches Herba were predicted via SwissTargetPrediction and DAVID. The compound-target-pathway-pharmacological action-efficacy network was constructed via Cytoscape. A total of 47 chemical constituents were identified, involving 95 targets and 56 signaling pathways. We preliminarily elucidated the pharmacological mechanisms of echinacoside, acteoside, isoacteoside, cistanoside F, 2'-acetylacteoside, cistanoside A, campneoside Ⅱ, salidroside, tubuloside B, 6-deoxycatalpol, 8-epi-loganic acid, ajugol, bartsioside, geniposidic acid, and pinoresinol 4-O-β-D-glucopyranoside, and predicted them to be the Q-markers of Cistanches Herba. This study identified the chemical constituents of Cistanches Herba, explained the pharmacological mechanism of the traditional efficacy of Cistanches Herba based on network pharmacology, and introduced the core concept of Q-markers to improve the quality evaluation of Cistanches Herba.

Study on critical quality attributes of Qingjin Huatan Decoction based on serum pharmacochemistry / 中国中药杂志

Qingjin Huatan Decoction is a classic prescription with the effects of clearing heat, moistening lung, resolving phlegm, and relieving cough. In order to explore the critical quality attributes of Qingjin Huatan Decoction, we identified the blood components of Qingjin Huatan Decoction by ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS) under the following conditions, chromatographic column: Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm); mobile phase: 0.1% formic acid acetonitrile(A)-0.1% formic acid in water(B); gradient elution; flow rate: 0.2 mL·min~(-1); column temperature: 30 ℃; injection volume: 5 μL. The electrospray ionization(ESI) source was used to collect data in both positive and negative ion modes under the following conditions, capillary voltage: 3 kV for the positive ion mode and 2 kV for the negative ion mode; ion source temperature: 110 ℃; cone voltage: 30 V; cone gas flow rate: 50 L·h~(-1); nitrogen degassing temperature: 350 ℃; degassing volume flow rate: 800 L·h~(-1); scanning range: m/z 50-2 000. In this experiment, a total of 66 related components of Qingjin Huatan Decoction were identified, including 22 prototype components and 44 metabolites. The results of this study preliminarily revealed the pharmacodynamic material basis of Qingjin Huatan Decoction in vivo, which has provided an experimental basis for the determination of quality markers of Qingjin Huatan Decoction and the development of new drugs.

Study on serum pharmacodynamic material basis of Gegen Qinlian Decoction in treatment of ulcerative colitis based on UHPLC-Q-Orbitrap-MS / 中国中药杂志

This study established a mouse model of ulcerative colitis and explored the serum transitional components of Gegen Qinlian Decoction by UHPLC-Q-Orbitrap-MS. Based on the exact relative molecular weight and MS/MS spectrum, 55 prototype components and 59 metabolites were identified from the model group, while 18 prototype components and 35 metabolites from the control group. The prototype components in serum were mainly flavonoids and the characteristic components of the model group were alkaloids. Glucuronidation, sulfonation, and glycosylation have been confirmed to be the main metabolic types in vivo. The results of comparative analysis of differences indicated that puerarin, baicalin, wogonoside, wogonin, chrysin, oroxylin A, berberine, berberrubine, and palmatine were the characteristic components in model state, which at the same time, were confirmed by pharmacological studies to be the serum pharmacodynamic material basis of Gegen Qinlian Decoction in the treatment of ulcerative colitis. This study has provided reference for explaining the metabolic transformation pattern and mechanism of action of Gegen Qinlian Decoction in vivo.

Pharmacokinetic behavior and brain tissue distribution of paeoniflorin combined with normal and toxic doses of strychnine in rats after percutaneous administration / 中国中药杂志

This study aims to establish a rapid and sensitive UPLC-MS/MS method for simultaneously determining the content of strychnine and paeoniflorin in plasma and brain tissue of rats, and compare the pharmacokinetic behavior and brain tissue distribution of paeoniflorin combined with normal and toxic doses of strychnine in rats after percutaneous administration. Compared with those in the toxic-dose strychnine group, the AUC_(0-t), AUC_(0-∞), and C_(max) of strychnine decreased by 51.51%, 45.68%, and 46.03%, respectively(P<0.01), and the corresponding values of paeoniflorin increased by 91.41%, 102.31%, and 169.32%, respectively(P<0.01), in the compatibility group. Compared with the normal-dose strychnine group, the compatibility group showed insignificantly decreased C_(max), AUC_(0-t), and AUC_(0-∞) of strychnine, increased C_(max) and T_(max) of paeoniflorin(P<0.01), 66.88% increase in AUC_(0-t), and 70.55% increase in AUC_(0-∞) of paeoniflorin. In addition, the brain tissue concentration of strychnine decreased and that of paeoniflorin increased after compatibility. The combination of paeoniflorin with normal dose and toxic dose of strychnine can inhibit the percutaneous absorption of strychnine, and greatly promote the percutaneous penetration of paeoniflorin, whereas the interaction mechanism remains to be explored. The UPLC-MS/MS method established in this study is easy to operate and has good precision. It is suitable for in vivo study of pharmacokinetic behavior and brain tissue distribution of paeoniflorin and strychnine after percutaneous administration in rats, which provides reference for the safe and rational clinical use of strychnine and the combined use of drugs, and lays a solid foundation for the development of external preparations containing Strychni Semen.

Comparison of chemical components between aerial and underground parts of Coptis chinensis based on UPLC-Q-TOF-MS~E technology / 中国中药杂志

The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-β-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP value>1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.

UHPLC-Q-Exactive Orbitrap MS/MS-based rapid identification of chemical components in substance benchmark of Kaixin San / 中国中药杂志

Ultra-performance liquid chromatography-quadrupole-electrostatic field Orbitrap mass spectrometry(UHPLC-Q-Exactive Orbitrap MS/MS) was used for rapid identification of the chemical components in Kaixin San substance benchmark. The gradient elution was performed through a Waters ACQUITY~(TM) BEH C_(18) column(2.1 mm×150 mm, 1.7 μm) with water-acetonitrile as mobile phase, a column temperature of 30 ℃, a flow rate of 0.3 mL·min~(-1), and a sample size of 1 μL. The scanning was performed in the negative ion mode. The complex component groups in Kaixin San substance benchmark were quickly and accurately identified and clearly assigned based on the comparison of the retention time and MS data with those of the reference substance as well as the relative molecular weight of the same or similar components in the mass spectrum database and literature. A total of 77 compounds were identified, including 26 saponins, 13 triterpenoid acids, 20 oligosaccharide esters, 5 xanthones, and 13 other compounds. The qualitative method established in this study can systematically, accurately, and quickly identify the chemical components in Kaixin San substance benchmark, which can provide a basis for the further analysis of its active components in vivo and the establishment of its quality control system.

Multi-index components of Scutellariae Barbatae Herba according to UHPLC-QTRAP-MS coupled with chemometrics / 中国中药杂志

The present study developed an ultra-fast liquid chromatography coupled with triple quadrupole-linear ion trap composite mass spectrometry(UHPLC-QTRAP-MS) to simultaneously determine the content of potential active components in Scutellariae Barbatae Herba and also to provide a reference approach for screening out the differential quality control components among different batches of Scutellariae Barbatae Herba. Chromatographic separations were conducted on a Thermo Acclaim~(TM) RSLC 120 C_(18) column(3.0 mm×100 mm, 2.2 μm) in a gradient program. The mobile phase consisted of 0.1% aqueous formic acid and acetonitrile, and the column temperature was maintained at 40 ℃. The flow rate was 0.4 mL·min~(-1) and the injection volume was 2 μL. The targeted compounds were monitored in the multiple reaction monitoring(MRM) mode. The acquired data were processed by hierarchical cluster analysis(HCA) and partial least square discriminant analysis(PLS-DA). Sixteen compounds all showed good linear relationship within the corresponding linear ranges and the R~2 values were all higher than 0.993 2. The RSDs of precision, repeatability, and stability were less than or equal to 3.7%. Mean recovery rates were in the range of 95.67% and 104.8% with RSDs≤3.2%. According to HCA and PLS-DA, all samples were clustered into four categories. Scutellarin, acteoside, scutellarein, and scutebarbatine X(VIP>1) were considered as differential chemical markers in the four categories. In conclusion, the developed method can be used for the simulta-neous determination of the multiple components and quality control of Scutellariae Barbatae Herba.

Methods for synchronous detection of 14 mycotoxins in Pseudostellariae Radix and investigation on its contamination / 中国中药杂志

This study aimed to establish a method for synchronous detection of 14 mycotoxins in Pseudostellariae Radix and investigate its contamination with mycotoxins, so as to provide technical guidance for monitoring the quality of Chinese medicinal materials and medication safety. The sample was extracted with 80% acetonitrile in an oscillator for 1 h, purified using the modified QuEChERS purifying agent(0.1 g PSA + 0.3 g C_(18) + 0.3 g MgSO_4), and separated on a Waters HSS T3 chromatographic column(2.1 mm×100 mm, 1.8 μm). The gradient elution was carried out with 0.1% formic acid in water and acetonitrile, followed by the scanning in the multi-reaction monitoring(MRM) mode and the analysis of mycotoxin contamination in 26 Pseudostellariae Radix samples. The recovery rates of the established method were within the range of 82.17%-113.6%, with the RSD values less than 7% and the limits of quantification(LOQ) being 0.019-0.976 μg·kg~(-1). The detection rate of 14 mycotoxins in 26 batches of medicinal materials was 53.85%. The detection rate of sterigmatocystin(ST) was the highest, followed by those of zearalenone(ZEN), aflatoxin G_2(AFG_2), fumonisin B_1(FB_1), HT-2 toxin, and nivalenol(NIV). Their respective detection rates were 38.46%, 26.92%, 23.08%, 11.54%, 11.54%, and 7.69%, with the pollution ranges being 1.48-69.65, 0.11-31.05, 0.11-0.66, 0.28-0.83, 20.86-42.56, and 0.46-1.84 μg·kg~(-1), respectively. The established method for the detection of 14 mycotoxins is accurate, fast and reliable. The research results have very important practical significance for guiding the monitoring and prevention and control of exogenous fungal contamination of Chinese medicinal materials.

Determination of eight active components of Bufei Huoxue Capsules in rat plasma and their pharmacokinetics by UHPLC-MS/MS / 中国中药杂志

An ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method was established to investigate the pharmacokinetic behaviors of psoralenoside, isopsoralenoside, calycosin-7-glucoside, ononin, psoralen, isopsoralen, methylnissolin, and neobavaisoflavone in rat plasma after oral administration of Bufei Huoxue Capsules. After SD rats were administered with Bufei Huoxue Capsules suspension by gavage, blood samples were collected from the inner canthus at different time points. After protein precipitation, plasma samples were separated on ACQUITY UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm). The mobile phase consisted of acetonitrile(A) and water(B) containing 0.1% formic acid in gradient elution. The positive and negative ions were measured simultaneously in the multi-reaction monitoring(MRM) mode. The pharmacokinetic parameters were calculated and fitted by DAS 3.2.8. Psoralenoside, isopsoralenoside, calycosin-7-glucoside, ononin, psoralen, isopsoralen, methylnissolin, and neobavaisoflavone were detected in the rat plasma after drug administration, with AUC_(0-t) of(3 357±1 348),(3 555±1 696),(3.03±0.88),(2.21±0.33),(1 787±522),(2 295±539),(5.69±1.41) and(3.40±0.75) μg·L~(-1)·h, and T_(max) of(1.56±0.62),(1.40±0.70),(0.21±0.05),(0.25±0.12),(0.26±0.11),(0.34±0.29),(0.74±0.59), and 0.25 h. The method is proved specific and repeatable and is suitable for the determination of psoralenoside, isopsoralenoside, calycosin-7-glucoside, ononin, pso-ralen, isopsoralen, methylnissolin, and neobavaisoflavone in the rat plasma, which can be applied to pharmacokinetic study.

Chromatographic profile of xanthones and flavonoids in the anti-dengue extracts of Fridericia samydoides (Cham. ) L. G. Lohmann (Bignoniaceae)

Abstract The flavonoids and xanthones present in the ethanol extracts of leaves and stems of Fridericia samydoides showed that anti-dengue activities in vitro were investigated qualitatively by liquid chromatography-ultraviolet-mass spectrometry in series. Nineteen flavones and fifteen xanthones were detected and characterized on the basis of their fragmentation pattern in the positive and negative ion mode tandem mass spectrometry spectra and ultraviolet bands. Acacetin, chrysin, vitexin, isovitexin, orientin, isoorientin, mangiferin, 2'-O-trans-caffeoylmangiferin, 2'-O-trans-coumaroylmangiferin and 2'-O-trans-cinnamoylmangiferin were identified by comparison with authentic samples. The other compounds detected were tentatively assigned by analysis of the spectral data and by comparison with literature reports. In addition, it performed the fractionation of the leaves extract leading to the isolation of mangiferin, isovitexin and isoorientin. All extracts and isolated compounds inhibited the Dengue virus replication cycle with EC50 less than 25.0 µg/mL for extracts and 272.5, 85.6 and 79.3 µg/mL for mangiferin, isovitexin and isoorientin, respectively.

Quantitative Proteomics Using Isobaric Labeling: A Practical Guide / 基因组蛋白质组与生物信息学报·英文版

In the past decade, relative proteomic quantification using isobaric labeling technology has developed into a key tool for comparing the expression of proteins in biological samples. Although its multiplexing capacity and flexibility make this a valuable technology for addressing various biological questions, its quantitative accuracy and precision still pose significant challenges to the reliability of its quantification results. Here, we give a detailed overview of the different kinds of isobaric mass tags and the advantages and disadvantages of the isobaric labeling method. We also discuss which precautions should be taken at each step of the isobaric labeling workflow, to obtain reliable quantification results in large-scale quantitative proteomics experiments. In the last section, we discuss the broad applications of the isobaric labeling technology in biological and clinical studies, with an emphasis on thermal proteome profiling and proteogenomics.

Optimization and validation of a highly sensitive method for determining glyphosate in human urine by solid-phase extraction and liquid chromatography with tandem mass spectrometry: a methodological study

BACKGROUND@#Glyphosate and its salt formulations are nonselective herbicides that have been extensively used worldwide, both for residential and agricultural purposes. The possible carcinogenicity and teratogenicity of glyphosate remain to be elucidated. We developed a sensitive and high-throughput analytical method for urinary glyphosate using liquid chromatography-tandem mass spectrometry with the aim of contributing to glyphosate exposure assessment in epidemiological studies.@*METHODS@#After urine dilution (creatinine matching dilution to 0.05 g creatinine/L), glyphosate was extracted using two types of solid phase extraction columns (SCX and NH2) with automated sample preparation instruments. The eluate was dried and dissolved in the mobile phase, followed by liquid chromatography-tandem mass spectrometry analysis. The optimized method was applied to urine samples obtained from 54 Japanese adults and children.@*RESULTS@#The results from the validation study demonstrated good recoveries (91.0-99.6%), within- and between-run precisions (< 15%), low detection limits (0.1 μg/L), and lower limit of quantification (0.3 μg/L). The detection frequency and median concentration of the urinary glyphosate in Japanese subjects were 59% and 0.25 μg/L (0.34 μg/g creatinine).@*CONCLUSIONS@#Our reliable determination method was successful in measuring urinary glyphosate concentration. Moreover, this is the first biomonitoring report of urinary glyphosate levels in the Japanese general population.

Evaluation of the bioequivalence of two formulations containing the combination of 400 mg of acetaminophen (paracetamol), 4 mg of phenylephrine and 4 mg of chlorpheniramine in capsules: open-label, three-way crossover study, partially replicated in healthy volunteers of both sexes

This study was carried out in order to compare the relative bioavailability of two different formulations containing 400 mg of acetaminophen + 4 mg of phenylephrine hydrochloride + 4 mg of chlorpheniramine maleate, Test formulation (Cimegripe®) and Reference formulation (Resfenol®) in 84 healthy volunteers of both sexes under fasting conditions. The study was conducted in a single dose, randomized, open-label, crossover 3-way and partially replicated. The tolerability was evaluated by the monitoring of adverse events and vital signs, results of clinical and laboratory tests. Plasma concentrations were quantified by validated bioanalytical methods using the ultra-performance liquid chromatography coupled to tandem mass spectrometry. The Cmax, Tmax, AUC0-t, AUC0-inf, T1/2 and Kel pharmacokinetic parameters were calculated from these obtained concentrations. The 90% confidence intervals were constructed for the ratio reference/test from the geometric average of the Cmax and AUC parameters which were comprised between 80% and 125%. Only the Cmax parameter of the phenylephrine was applied the scaled average bioequivalence due to the intraindividual coefficient of variation > 30% obtained, thus extending the acceptance limits of the interval. It can be concluded that the two formulations were bioequivalent in terms of rate and absorption extent and thus interchangeable

Photocatalytic Degradation of Textile dye Orange-122 Via Electrospray Mass Spectrometry

Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.

Decreased plasmatic spermidine and increased spermine in mild cognitive impairment and Alzheimer's disease patients

Abstract Background Current evidence suggests that upregulation of polyamines system plays a role both in cognitive deficit and synaptic loss observed in Alzheimer's disease (AD). Objective The aim of this study was to determine the plasmatic concentration of polyamines in mild cognitive impairment (MCI) and AD patients in comparison with healthy controls (HC). Methods Plasmatic polyamines were quantified using the AbsoluteIDQ® p180 and liquid chromatography coupled to tandem mass spectrometry (LC/MS-MS). Results The study group comprised 34 AD patients, 20 MCI and 25 HC. All individuals were followed for 4 years. During this period 8 amnestic MCI patients (40% of the MCI sample at baseline) converted to AD. Spermidine level was lower in both patient groups (AD; MCI) compared to HC (p = 0.007). Plasma levels of spermine were higher in the MCI group (p < 0.001), but decreased in the sub-sample of MCI patients who converted to AD (p = 0.043). No statistically significant differences were found in ornithine and putrescine levels (p = 0.056 and p = 0.126, respectively). Discussion Our results suggest dynamic changes in the expression of polyamines in the MCI-AD continuum.

Identification of pathogenic and nonpathogenic Leptospira species of Brazilian isolates by Matrix Assisted Laser Desorption/Ionization and Time Flight mass spectrometry

ABSTRACT Matrix Assisted Laser Desorption/Ionization and Time of Flight mass spectrometry (MALDI-TOF MS) is a powerful tool for the identification of bacteria through the detection and analysis of their proteins or fragments derived from ribosomes. Slight sequence variations in conserved ribosomal proteins distinguish microorganisms at the subspecies and strain levels. Characterization of Leptospira spp. by 16S RNA sequencing is costly and time-consuming, and recent studies have shown that closely related species (e.g., Leptospira interrogans and Leptospira kirschneri) may not be discriminated using this technology. Herein, we report an in-house Leptospira reference spectra database using Leptospira reference strains that were validated with a collection of well-identified Brazilian isolates kept in the Bacterial Zoonosis Laboratory at the Veterinary Preventive Medicine and Animal Health Department at Sao Paulo University. In addition, L. interrogans and L. kirschneri were differentiated using an in-depth mass spectrometry analysis with ClinProTools™ software. In conclusion, our in-house reference spectra database has the necessary accuracy to differentiate pathogenic and non-pathogenic species and to distinguish L. interrogans and L. kirschneri.

Avaliações toxicológicas das alterações genotóxicas e epigenóticas induzidas por Aroclor 1254 em testí­culo, espermatozóides, fí­gado e rim de camundongos / Toxicological assessments of genotoxic and epigenetic changes induced by Aroclor 1254 in testis, sperm, liver and kidney of mice

As bifenilas policloradas (PCBs) são um grupo de compostos hidrocarbonetos halogenados aromáticos, bioacumulativos em organismos vivos e persistente no ambiente. Além da atividade disruptora endócrina, os PCBs podem aumentar os níveis de espécies reativas de oxigênio (ROS), levando ao estresse oxidativo e alteração da metilação de DNA que são fatores importantes nas etiologias da hepatotoxicidade, infertilidade masculina e doença renal. Estes agentes tóxicos podem causar disfunção mitocondrial e distúrbios que afetam a produção de ATP, ROS e morte celular, ocasionando danos à saúde humana. O presente trabalho tem como objetivo investigar possíveis alterações genotóxicas e epigenéticas causadas pelo aroclor 1254 em fígado, rim e testículo, além de verificar a indução de estresse oxidativo e disrupção dos metabólitos intermediários do ciclo de Krebs nos referidos tecidos. Camundongos machos C57/BL6 foram expostos ao Aroclor 1254 em diferentes doses (5, 50, 500 e 1000 ug/kg) por gavagem, uma vez a cada três dias, durante 50 dias. Após a exposição, os animais foram eutanasiados, os órgãos coletados e espermatozoides obtidos a partir dos epidídimos. A peroxidação lipídica em plasma e tecidos foi avaliada pela quantificação de malonaldeído (MDA) por HPLC/DAD. Os níveis de intermediários da via glicolítica, do ciclo de Krebs, de alguns nucleotídeos e aminoácidos, marcas epigenéticas (5-mC e 5-hmC) e adutos de DNA (8-oxodG e CEdG) foram quantificados por HPLC-ESI-MS/MS. A abordagem de benchmark dose (BMD) foi utilizada para a modelagem dose resposta. Após exposição, não foram observadas diferenças significativas da variação da massa corporal, e a razão do peso testicular, fígado e rim por massa corporal. No tecido hepático, foi observado aumento da peroxidação lipídica. Houve redução significativa dos níveis de ATP, ADP, razão NADP+/NADPH, piruvato, malato, fumarato e glutamato. Observou-se redução significativa dos níveis de 5-mC e 5-hmC no DNA nuclear (nDNA), enquanto não foram observadas alterações dos níveis dos adutos. Em DNA mitocondrial (mtDNA) não foram observadas alterações nas marcas epigenéticas, no entanto foi obtido aumento significativo no aduto 8-oxodG após exposição ao Aroclor 1254. No tecido renal foi observado aumento significativo de MDA. Houve aumento significativo dos níveis de lactato e malato e reduções de ATP, ADP, glutamina, NAD+. Foi observada a hipohidroximetilação do mtDNA. As marcas 5-mC de mtDNA, 5mC de nDNA e adutos de DNA nuclear e mitocondrial não apresentaram diferenças após exposição a PCBs. Nos testículos foi verificada redução significativa dos níveis de glutamato, malato, succinato, fumarato e razão NADH/NAD+, hipohidroximetilção em mtDNA e hipermetilação em nDNA. Não foram observadas alterações de 5-mC em mtDNA e 5hmC em nDNA. Não foram verificadas alterações dos níveis de MDA e adutos em nDNA. Adicionando, foi observada redução dos níveis de 5-mC em DNA global de espermatozoide. Os limites inferiores do intervalo de confiança da BMD foram estimados para que estes marcadores possam ser usados na avaliação de riscos de PCBs. Os dados obtidos apontam o Aroclor 1254 como indutor de alterações do metabolismo intermediário, das marcas epigenéticas e estresse oxidativo. Essas alterações podem afetar vias celulares, levando à morte ou transformação, e aumentando o risco de doenças

Polychlorinated biphenyls (PCBs) are a group of aromatic halogenated hydrocarbon compounds, which bioaccumulate in living organisms and is persistent in the environment. Besides their endocrine disrupting activity, PCBs may increase the levels of reactive oxygen species (ROS), leading to oxidative stress and alter DNA methylation that are important factors in the etiology of liver toxicity, male infertility, and kidney disease. These toxic agents can cause mitochondrial dysfunction and disorders that affect the production of ATP, ROS and cell death, thereby leading to health-related problems. The present work aimed at investigating possible genotoxic and epigenetic changes caused by aroclor 1254 in the liver, kidney and testis, as well as determine the induction of oxidative stress and disruption of intermediate metabolites in these tissues. Male C57/BL6 mice were exposed to Aroclor 1254 at different doses (5, 50, 500 and 1000 µg/kg) by gavage, once every three days, for 50 days. After the exposure period, the animals were euthanized, organs collected, and sperms obtained from the epididymis. Lipid peroxidation in plasma and tissues was determined by quantification of malonaldehyde (MDA) using HPLC/DAD. The levels of intermediate metabolites, epigenetic marks (5-mC and 5-hmC) and DNA adducts (8-oxodG and CEdG) were quantified by HPLC-ESI-MS/MS. The Benchmark dose approach (BMD) was used for dose response modeling. No significant differences in body weight variation, testicular, liver and kidney weight to body weight ratio were observed after exposure. However, in hepatic tissues, an increase in lipid peroxidation was observed. There were significant decreases in the intermediate metabolites including the levels of ATP, ADP, pyruvate, NADP+/NADPH ratio, malate and fumarate, as well as glutamate. Significant reduction of 5-mC and 5-hmC levels in nuclear DNA (nDNA) were observed, whereas no changes were observed in DNA adducts. The epigenetic marks in mitochondrial DNA (mtDNA) were not changed; however, a significant increase was observed in 8-oxodG adduct after exposure to Aroclor 1254. In renal tissues, data showed a significant increase in MDA, while for the intermediate metabolites, the levels of lactate and malate were significantly elevated, whereas significant reductions were recorded for ATP, ADP, glutamine, and NAD+. Hypohydroxymethylation was observed in mtDNA. The 5-mC of mtDNA, 5mC of nDNA and nuclear and mtDNA adducts did not show differences after PCBs exposure. For the testicles, significant reductions in the levels of glutamate, malate, succinate, fumarate and NADH/NAD+ ratio were observed. The PCBs also induced hypohydroxymethylation in mtDNA and hypermethylation in nDNA, but there were no changes of 5-mC in mtDNA and 5-hmC in nDNA. A reduction of nDNA adducts 8-oxodG was observed. No changes were observed in the level of MDA and DNA adducts of nDNA. However, after PCBs exposure there was a significant decrease of 5-mC in global DNA of spermatozoa. The lower bound confidence interval on BMD, which were estimated for these markers can be used in the risk assessment of PCBs. Collectively, the data obtained in this study indicate that Aroclor 1254 induces alteration of intermediate metabolites, epigenetic marks and oxidative stress. These changes can adversely affect cells and cellular pathways, therefore increase the risk of cell death or transformation

Standardization of a protocol for shotgun proteomic analysis of saliva

Abstract Saliva contains numerous proteins and peptides, each of them carries a number of biological functions that are very important in maintaining the oral cavity health and also yields information about both local and systemic diseases. Currently, proteomic analysis is the basis for large-scale identification of these proteins and discovery of new biomarkers for distinct diseases. Objective This study compared methodologies to extract salivary proteins for proteomic analysis. Material and Methods Saliva samples were collected from 10 healthy volunteers. In the first test, the necessity for using an albumin and IgG depletion column was evaluated, employing pooled samples from the 10 volunteers. In the second test, the analysis of the pooled samples was compared with individual analysis of one sample. Salivary proteins were extracted and processed for analysis by LC-ESI-MS/MS. Results In the first test, we identified only 35 proteins using the albumin and IgG depletion column, while we identified 248 proteins without using the column. In the second test, the pooled sample identified 212 proteins, such as carbonic anhydrase 6, cystatin isoforms, histatins 1 and 3, lysozyme C, mucin 7, protein S100A8 and S100A9, and statherin, while individual analysis identified 239 proteins, among which are carbonic anhydrase 6, cystatin isoforms, histatin 1 and 3, lactotransferrin, lyzozyme C, mucin 7, protein S100A8 and S100A9, serotransferrin, and statherin. Conclusions The standardization of protocol for salivary proteomic analysis was satisfactory, since the identification detected typical salivary proteins, among others. The results indicate that using the column for depletion of albumin and IgG is not necessary and that performing individual analysis of saliva samples is possible.

A sensitive bioanalytical method development and validation of cabozantinib in human plasma by LC-ESI-MS/MS

ABSTRACT A simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantification of cabozantinib (CZ) in human plasma using cabozantinib-d4 (CZD4) as an internal standard (IS). Chromatographic separation was performed on Xbridge C18, 50 x 4.6 mm, 5 mm column with an isocratic mobile phase composed of 10mM Ammonium formate and Methanol in the ratio of (20:80 v/v), at a flow-rate of 0.7 mL/min. CZ and CZD4 were detected with proton adducts at m/z 502.2 ® 391.1 and 506.3 ® 391.2 in multiple reaction monitoring (MRM) positive mode respectively. Liquid-Liquid extraction method was used to extract the drug and IS. The method was validated over a linear concentration range of 5.0-5000.0 pg/mL with correlation coefficient (r2) ≥ 0.9994. This method demonstrated intra and inter-day precision within 1.95 to 2.37 and 2.93 to 9.3 % and Accuracy within 101.4 to 102.4 and 99.5 to 104.8 %. Cabozantinib was found to be stable throughout freeze-thawing cycles, bench top and postoperative stability studies

Actiflagelin, a new sperm activator isolated from Walterinnesia aegyptia venom using phenotypic screening

Sperm contains a wealth of cell surface receptors and ion channels that are required for most of its basic functions such as motility and acrosome reaction. Conversely, animal venoms are enriched in bioactive compounds that primarily target those ion channels and cell surface receptors. We hypothesized, therefore, that animal venoms should be rich enough in sperm-modulating compounds for a drug discovery program. Our objective was to demonstrate this fact by using a sperm-based phenotypic screening to identify positive modulators from the venom of Walterinnesia aegyptia. Methods Herein, as proof of concept that venoms contain interesting compounds for sperm physiology, we fractionated Walterinnesia aegyptia snake venom by RP-HPLC and screened for bioactive fractions capable of accelerating mouse sperm motility (primary screening). Next, we purified each compound from the positive fraction by cation exchange and identified the bioactive peptide by secondary screening. The peptide sequence was established by Edman sequencing of the reduced/alkylated compound combined to LC-ESI-QTOF MS/MS analyses of reduced/alkylated fragment peptides following trypsin or V8 protease digestion. Results Using this two-step purification protocol combined to cell phenotypic screening, we identified a new toxin of 7329.38 Da (actiflagelin) that activates sperm motility in vitro from OF1 male mice. Actiflagelin is 63 amino acids in length and contains five disulfide bridges along the proposed pattern of disulfide connectivity C1-C5, C2-C3, C4- C6, C7-C8 and C9-C10. Modeling of its structure suggests that it belongs to the family of three finger toxins with a noticeable homology with bucandin, a peptide from Bungarus candidus venom. Conclusions This report demonstrates the feasibility of identifying profertility compounds that may be of therapeutic potential for infertility cases where motility is an issue.(AU)