Vitamin D and Its Metabolites Status before and during Chemotherapy in Caucasian Breast Cancer Patients.

BACKGROUND: The predictive role of vitamin D (VD) in breast cancer (BC) patients' survival is still being investigated. This paper aims to evaluate the changes in VD metabolites during chemotherapy (CTH) and the predictive role of VD status in Caucasian BC patients treated with CTH. METHODS: Vitamin D and its metabolites were assessed with reference LC-MS/MS methodology in 98 consecutive BC patients starting CHT, after 3 and 6 months, and compared to the control group. RESULTS: The frequency of VD deficiency in BC patients was greater than in the control group (56.1% vs. 37.2%). After 6 months of CTH, the number of VD-deficient BC patients slightly increased to 60%. The concentrations of VD active forms [25(OH)D2, 25(OH)D3], and catabolites [24,25(OH)2D3 and 3-epi-25(OH)D3] decreased after 3 and 6 months of CTH compared to the baseline values. Strong positive correlations between concentrations of 3-epi-25(OH)D3 and 25(OH)D in both groups were found. Similar correlations were also observed between 24,25(OH)2D3 and 25(OH)D levels. Kaplan-Meier survival analysis showed significantly longer survival in BC patients without deficiency (>20 ng/mL) at baseline (HR = 2.44 (95% CI 1.07-5.59), p = 0.026). CONCLUSIONS: (1) Our data provide further evidence that BC patients before CTH are more VD-deficient than the general population and this deficiency increases further during CTH treatment, as observed using the reference LC-MS methodology. (2) Presented results show that VD catabolism is not affected in BC patients. (3) The poorer survival in VD-deficient BP patients supports the importance of VD supplementation in BC patients with 25(OH)D levels below 20 ng/mL.

Proteomics Analysis of Polyphyllin D-Treated Triple-Negative Breast Cancer Cells Reveal the Anticancer Mechanisms of Polyphyllin D.

Polyphyllin D (PD), one of the important steroid saponins in traditional medicinal herb Paris polyphylla, has been demonstrated to have anticancer activity both in vitro and in vivo. However, the mechanisms through which PD exerts its anticancer effects in triple-negative breast cancer (TNBC) remain unclear. Our study was presented to evaluate the anticancer effect and the potential mechanisms of PD in two TNBC cell lines, BT-549 and MDA-MB-231. Through comprehensively comparing the liquid chromatography-tandem mass spectrometry (LC-MS/MS) data of PD-treated and untreated BT-549 and MDA-MB-231 cells, we found that PD could induce apoptosis of TNBC cells by activating oxidative phosphorylation pathway in BT-549 cells, as well as inhibiting spliceosome function alteration in MDA-MB-231 cells. These results suggested that the mechanisms underlying the pro-apoptotic effect of PD on TNBC may be cell type-specificity-dependent. Moreover, we found that nodal modulator 2/3 (NOMO2/3) were downregulated both in PD-treated BT-549 and MDA-MB-231 cells, suggesting that NOMO2/3 may be the potential target of PD. Verification experiments revealed that PD deceased NOMO2/3 expression at protein level, rather than mRNA level. Whether NOMO2/3 are the upstream modulators of oxidative phosphorylation pathway and spliceosome needs further validation. In conclusion, a comprehensive proteomics study was performed on PD-treated or untreated TNBC cells, revealing the anticancer mechanisms of PD.

[QuEChERS-liquid chromatography-tandem mass spectrometry for determination of 22 triazole pesticide residues in Chinese herbal medicines].

Eight well-known herbals in Zhejiang Province, Zhebawei, are commonly used as traditional Chinese herbal medicines owing to their rich active ingredients. However, the unavoidable use of pesticides during agricultural production has led to pesticide residue problems in these herbs. In this study, a simple, rapid, and accurate method was established to determine 22 triazole pesticide residues in Zhebawei. An improved QuEChERS method was used for sample pretreatment, and Rhizoma Atractylodis Macrocephalae was used as a representative sample. The sample was extracted with acetonitrile to eliminate some polar and nonpolar compounds, pigments, and other impurities, and the purification effects of multiwalled carbon nanotubes (MWCNTs), amino-modified multiwalled carbon nanotubes (MWCNTs-NH2), carboxylated multiwalled carbon nanotubes (MWCNTs-COOH), crosslinked polyvinylpyrrolidone (PVPP), zirconium dioxide (ZrO2), 3-(N,N-diethylamino)-propyltrimethoxysilane (PSA), octadecyl (C18), and graphitized carbon black (GCB) were compared. MWCNTs-COOH and C18 were selected as the purification adsorbents, and their dosages were systematically optimized. The combination of 10 mg of MWCNTs-COOH and 20 mg of C18 was eventually selected as the purification adsorbents. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for analysis, and box graphs were plotted to present the dispersion of each group of recoveries, thus enabling the identification of the data outliers, dispersion distribution, and data symmetry. The established method was systematically verified and showed good linearity over the concentration range of 1-200 µg/L (except for bromuconazole, epoxiconazole, and etaconazole) with correlation coefficients >0.99. The average recoveries of the 22 pesticides at spiked levels of 10, 20, 100, and 200 µg/kg were in the range of 77.0%-115% with relative standard deviations (RSDs) <9.4%. The limits of detection and quantification were 1-2.5 µg/kg and 10-20 µg/kg, respectively. The applicability of the developed method to other herbals was investigated at 100 µg/kg, and the average recoveries of the target pesticides in different matrices ranged from 76.4% to 123% with RSDs <12.2%. Finally, the method established was used to detect triazole pesticide residues in 30 actual Zhebawei samples. The results showed that triazole pesticides were present in Bulbus Fritillariae Thunbergii and Dendranthema Morifolium. Difenoconazole was detected in Bulbus Fritillariae Thunbergii at contents ranging from 41.4 µg/kg to 110 µg/kg, while difenoconazole, myclobutanil, triadimenol and propiconazole were detected in Dendranthema Morifolium at contents ranging from 16.1 µg/kg to 250 µg/kg. The established method can meet the requirements for the accurate quantitative analysis of triazole fungicides in Zhebawei.

Qualitative and quantitative mass spectrometry comparison of characteristic galactosyl lactose isomers from goat milk at different lactation stages.

Galactooligosaccharides are composed mainly of galactosyl lactose, which is important for infant growth and as a functional food additive. Although galactosyl lactose is abundant in goat milk, its complex structure has hindered the separation and analysis of its isomers. In this study, 5 isomers of goat milk galactosyl lactose were separated by HPLC: ß6'-galactosyl lactose (ß6'-GL), α6'-galactosyl lactose (α6'-GL), ß4'-galactosyl lactose (ß4'-GL), α3'-galactosyl lactose (α3'-GL), and ß3'-galactosyl lactose (ß3'-GL). This composition differs from that of commercial galactooligosaccharide products, which comprise mainly ß-configuration oligosaccharides. The isomers were then qualitatively and quantitatively compared at different lactation stages using online HPLC-mass spectrometry. Relative quantitative analysis showed that the total content of the 5 galactosyl lactose isomers was highest in transitional goat milk. Specifically, ß3'-GL was the main isomer in colostrum and α3'-GL was the main isomer in transitional and mature milk. ß6'-Galactosyl lactose and ß4'-GL tended to increase and then decrease during lactation. Moreover, α3'-GL content was 2 times higher than in colostrum and 10 times higher in transitional milk than in mature milk; in contrast, for ß3'-GL, the values were 5 and 2 times higher, respectively. Absolute quantitative analysis revealed that ß3'-GL was the most abundant isomers in colostrum (32.3 mg/L), and α3'-GL was the most abundant in transitional milk (88.1 mg/L) and mature milk (36.3 mg/L). These findings provide an important quantitative basis for understanding the relationship between structure and function of galactosyl lactose in goat milk, as well as its exploitation as a functional food.

[Liquid chromatography-mass spectrometry-based metabolomics study of the efficacy of Chinese medicine asthma-relieving decoction on respiratory syncytial virus infection].

Respiratory syncytial virus (RSV) can cause lower respiratory tract infections, such as bronchiolitis in infants. In China, traditional asthma-relieving medicine has numerous clinical applications in the treatment of RSV infections. However, due to the complexity of the traditional Chinese medicine system, its therapeutic mechanism and main pharmacological components remain unclear. Metabolomics can be used to analyze the efficacy of traditional Chinese medicine to provide modern scientific evidence for such treatments. In this study, an animal model experiment was performed with seven groups of three-week-old rats. The model group and five intervention groups were inoculated nasally with RSV for three consecutive days, and the normal group was treated with the same amount of saline for three consecutive days under the same conditions. In parallel, the five intervention groups were treated separately with the following via intragastric administration for seven consecutive days: asthma-relieving traditional Chinese medicine decoction, its three constituent agents (ascending (xuan) therapy, descending (jiang) therapy, pyretic clearing (qing) therapy), and ribavirin. Both normal group and RSV model group were administered with normal saline via intragastric administration as controls for seven consecutive days. The fundus plasma of rats in each group was collected on day 0, day 3, and day 7. Liquid chromatography-mass spectrometry-based untargeted metabolomics analysis was performed to investigate the changes in the metabolome after RSV infection, the effects of the asthma-relieving decoction on the regulation of metabolites related to RSV infection, and the primary source of efficacy. The detected metabolite ions were corrected using internal standards. Multivariate analysis of ions with an RSD value of less than 30% in quality control (QC) samples was used to construct principal component analysis models to monitor the overall metabolic changes of each group. The results showed that, during RSV infection and treatment, the asthma-relieving decoction and the positive control ribavirin had similar effects on the overall metabolic regulation of RSV-infected rats. Among the three asthma-relieving decoction constituent agents, the ascending (xuan) therapy agents which was composed of ephedra and ginkgo had a closer metabolic regulation effect with asthma-relieving decoction, and might be the main source of pharmacological efficacy. Based on the retention time, m/z value and tandem mass spectra in the database established by our laboratory, a total of 150 metabolites were identified. Paired t-tests were performed using data of the identified metabolites before and after RSV infection in each group, and it was found that 83 metabolite levels significantly changed after RSV infection, indicating that RSV infection could lead to disorders of multiple metabolic pathways in rats. The altered pathways included aminoacyl-tRNA biosynthesis, phenylalanine, tyrosine, and tryptophan biosynthesis, primary bile acid biosynthesis, phenylalanine metabolism and sphingomyelin metabolism. On the third day, the asthma-relieving decoction had regulatory effects on several metabolites such as bile acids, amino acids, organic acids, lipids, etc. Among the three asthma-relieving decoction constituent agents, the ascending (xuan) therapy agents had more similar effects on the regulation of metabolites with the asthma-relieving decoction. On the other hand, the descending (jiang) therapy agents and pyretic clearing (qing) therapy agents down-regulated the abnormal increase in acylcarnitine caused by the RSV infection. Additionally, both asthma-relieving decoction and its constituent agents could maintain the stability of the immune system and metabolism of the intestinal flora in rats. This study used metabolomics to evaluate the efficacy of an asthma-relieving decoction and demonstrate the metabolites and the corresponding changes after asthma-relieving decoction-based treatment. It provides theoretical support for research on the therapeutic mechanism and active ingredients of asthma-relieving decoction.

Immunosuppressant quantification in intravenous microdialysate - towards novel quasi-continuous therapeutic drug monitoring in transplanted patients.

OBJECTIVES: Therapeutic drug monitoring (TDM) plays a crucial role in personalized medicine. It helps clinicians to tailor drug dosage for optimized therapy through understanding the underlying complex pharmacokinetics and pharmacodynamics. Conventional, non-continuous TDM fails to provide real-time information, which is particularly important for the initial phase of immunosuppressant therapy, e.g., with cyclosporine (CsA) and mycophenolic acid (MPA). METHODS: We analyzed the time course over 8 h of total and free of immunosuppressive drug (CsA and MPA) concentrations measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in 16 kidney transplant patients. Besides repeated blood sampling, intravenous microdialysis was used for continuous sampling. Free drug concentrations were determined from ultracentrifuged EDTA-plasma (UC) and compared with the drug concentrations in the respective microdialysate (µD). µDs were additionally analyzed for free CsA using a novel immunosensor chip integrated into a fluorescence detection platform. The potential of microdialysis coupled with an optical immunosensor for the TDM of immunosuppressants was assessed. RESULTS: Using LC-MS/MS, the free concentrations of CsA (fCsA) and MPA (fMPA) were detectable and the time courses of total and free CsA comparable. fCsA and fMPA and area-under-the-curves (AUCs) in µDs correlated well with those determined in UCs (r≥0.79 and r≥0.88, respectively). Moreover, fCsA in µDs measured with the immunosensor correlated clearly with those determined by LC-MS/MS (r=0.82). CONCLUSIONS: The new microdialysis-supported immunosensor allows real-time analysis of immunosuppressants and tailor-made dosing according to the AUC concept. It readily lends itself to future applications as minimally invasive and continuous near-patient TDM.

[Determination of higenamine in Chinese herbal medicine, condiments, and topical medicine by QuEChERS combined with liquid chromatography-tandem mass spectrometry].

A method combining QuEChERS with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of higenamine in Chinese herbal medicine, condiments, and topical medicine. The sample was subjected to extraction using a formic acid-ethanol mixture, followed by purification of the QuEChERS sorbents; then, the extraction solution was introduced into the LC-MS/MS system for detection in multiple reaction monitoring (MRM) mode. Under the optimal conditions, the detection limit of the developed method was 0.03 ng/g, and the linear range was 0.10-100 ng/g with a relative standard deviation (RSD) of 4.33% (0.5 ng/g, n=7). The method was then applied to the determination of higenamine in 13 kinds of Chinese herbal medicine, four kinds of condiments, and a topical medicine. Higenamine was detected in dried lotus leaf, dried lotus seed, Chinese yam, Yuzhu, Yam, Sichuan pepper, Cassia, and the topical medicine at 9667.6, 1183.8, 21.5, 8.2, 8.5, 148.6, 21.3, and 173.3 µg/kg, respectively. The recoveries of higenamine in Sichuan pepper and cassia was 92.6%-109.8%. In conclusion, the method is fast, simple, reliable, and suitable for use in batch operation.

Evaluation of the new restandardized Abbott Architect 25-OH Vitamin D assay in vitamin D-insufficient and vitamin D-supplemented individuals.

BACKGROUND: Recently, Abbott Diagnostics has restandardized the Architect 25(OH)D assay against the NIST SRM 2972. We have evaluated the analytical and clinical performance of the restandardized Architect 25(OH)D assay and compared its performance with a NIST-traceable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method and the Roche total 25(OH)D assay in vitamin D-insufficient individuals before and after vitamin D3 supplementation. METHODS: Frozen serum samples were obtained from 88 healthy subjects with self-perceived fatigue and vitamin D-insufficiency <50 nmol L-1 who were randomized to receive a single 100 000 IU dose of vitamin D3 (n = 48) or placebo (n = 40). Total 25(OH)D concentrations were measured before and 4 weeks after supplementation by the restandardized Architect 25(OH)D assay, LC-MS/MS, and Roche assay. RESULTS: The Architect 25(OH)D assay showed an intra- and inter-assay imprecision of <5%. Comparison of the Architect assay with the LC-MS/MS method showed a good correlation in both vitamin D-insufficient and vitamin D-supplemented subjects, however, with a negative mean bias of 17.4% and 8.9%, respectively. As compared to the Roche assay, the Abbott assay underestimated 25(OH)D results in insufficient subjects (<50 nmol L-1 ) with a mean negative bias of 17.1%, this negative bias turned into a positive bias in supplemented subjects. Overall there was a moderate agreement in classification of vitamin D-insufficient and -supplemented individuals into different vitamin D states between the Architect 25(OH)D method and LC-MS/MS. CONCLUSION: The routine use of the restandardized Architect 25(OH)D results in a slight underestimation of circulating total 25(OH)D levels at lower concentrations and thus potential misclassification of vitamin D status.

Determination of tocopherols and their metabolites by liquid-chromatography coupled with tandem mass spectrometry in human plasma and serum.

Several studies are increasingly underlying the biological role of vitamin E metabolites as bioactive compounds with anti-inflammatory, anti-proliferative and anti-atherogenic activity. A quantitative method for the simultaneous determination in human plasma and serum of vitamin E (α-tocopherol, α-T and γ-tocopherol, γ-T) and its cytochrome P-450 metabolites: 13'-hydroxychromanol (α-13'-OH), 13'-carboxychromanol (α-13'-COOH) and carboxyethyl hydroxychromanols (α-CEHC and γ-CEHC), was developed and validated. After enzymatic hydrolysis and deproteinization, the metabolites were extracted with a mixture of hexane/ methyl tertiary butyl ether (2/1, v/v). The separation was achieved by reversed phase chromatography and the analytes detected by a triple quadrupole mass analyser using electrospray ionization in positive mode (LC-MS/MS). α-T and γ-T were extracted separately without enzymatic hydrolysis. The analytes were quantified with the isotopic dilution method. After an extensive validation study (three levels in three different occasions for a total of 54 experiments), the procedure was successfully applied to the analysis of sera of healthy volunteers (before and after supplementation with α-T) and plasma of patients affected by chronic kidney disease. Finally, the structures of three unknown compounds found in blood and related to the long chain metabolites (α-13'-OH and α-13'-COOH) were further investigated using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS).

Validated quantification method for five ephedrines in dietary supplements using LC-MS/MS: Application to 503 cases.

Ephedrines in dietary supplements can arise from herbs or illegal adulteration so a liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for separation and quantification of ephedrine, pseudoephedrine, norephedrine, norepseudoephedrine, and methyl-ephedrine, some of which are isomer pairs of pseudo-structures. This method includes liquid-liquid extraction of ephedrines from three typical dietary supplement matrices-solid, liquid, and oil-as well as liquid chromatographic separation. After liquid chromatographic separation, ephedrines are qualitatively and quantitatively analyzed using triple quadrupole mass spectrometry with positive electrospray ionization in multi-reaction monitoring (MRM) mode. Ephedrine recoveries in a solid matrix ranged from 53.3-91.5%, in a liquid matrix from 56.4-102.3%, and in an oil matrix from 51.7-01.2%. Linearity ranges were 10-1000ng/g in solid and oil matrix and 1-100ng/ml in liquid matrix. Accuracy was -11.5-16.3%. Intra-day and inter-day variation are less than 5.9% and 7.3%, respectively. Expanded uncertainty of quantification is less than 0.123ng/g in a solid matrix, less than 0.139ng/ml in a liquid matrix, and less than 0.158ng/g in an oil matrix. Data collected for more than 500 routine samples are presented and discussed.

Single-shot multi-reaction monitoring of intact marker conjugates for quantitative profiling of human major microsomal glucuronidations and its utility to screen inhibitors from medicinal herbs.

UDP-glucuronosyltransferase (UGT) is a polymorphic family of conjugating enzymes responsible for the elimination of a myriad of xenobiotics and endogenous compounds. The precise reaction phenotyping of this multi-isoform superfamily is hampered by a lack of fast generic methods for directly measuring the diverse glucuronoconjugate metabolites for comprehensive profiling of UGT isoform-specific glucuronidations. We report here a single-shot liquid chromatography-tandem mass spectrometry (LC-MS/MS) method enabling the simultaneous direct measurement of nine intact glucuronides from hepatic microsomal glucuronidations mediated by a battery of isoforms (1A1, 1A3, 1A4, 1A6, 1A9, 2B7, 2B10, 2B15, and 2B17), which represent the majority of human UGTs in drug metabolism. This new method is based on post-incubation pooling of the individual probe reaction samples for nine-in-one cassette analysis with polarity switching multiple reaction monitoring (MRM) of all the marker glucuronides within a single LC-MS/MS injection. The pooled sample strategy overcomes the cross-interferences among the cocktail substrates and also increases the throughput. The periodic polarity switching of the LC-MRM acquisition expands the glucuronide profiling coverage using a generic single-run analysis. The source-induced dissociation of the glucuronoconjugates was evaluated as a generic alternative for their quantitation as their free aglycones, but a significant bias occurs against the traditional assumption that the parent substrates could be used as the surrogates for quantifying their glucuronide metabolites without authentic standards. After collective validations for analyte quantitation and enzyme kinetics, this single-shot cassette quantitative profiling approach may prove useful in large-scale phenotyping of human glucuronidations and rapid screening for UGT inhibitors in natural products. Graphical abstract Multi-reaction monitoring of intact conjugate metabolites for quantitative profiling of human major glucuronidations.

Simultaneous determination of isoflavones and resveratrols for adulteration detection of soybean and peanut oils by mixed-mode SPE LC-MS/MS.

To ensure authenticity of vegetable oils, isoflavones (genistein, genistin, daidzein and daidzin) and resveratrols (cis-resveratrol and trans-resveratrol) were selected as the putative markers for adulteration of soybean and peanut oils. Firstly, mixed mode solid-phase extraction coupled with liquid chromatography tandem mass spectrometry (mixed-mode SPE LC-MS/MS) method was developed to analyze isoflavones and resveratrols in vegetable oils. The concentration of marker compounds in vegetable oils were 0.08-1.47mgkg(-1) for daidzein, ND-78.9µgkg(-1) for daidzin, 0.40-5.89mgkg(-1) for genistein, 1.2-114.9µgkg(-1) for genistin, 3.1-85.0µgkg(-1) for trans-resveratrol and 1.9-51.0µgkg(-1) for cis-resveratrol, which are compatible with the raw materials for oil press. Additionally, the applicability of this method has been successfully tested in thirteen vegetable oils from the market. Mixed-mode SPE LC-MS/MS method can simultaneously detect isoflavones and resveratrols in vegetable oils and assess adulteration and quality of soybean and peanut oils.

Simultaneous determination of seventeen mycotoxins residues in Puerariae lobatae radix by liquid chromatography-tandem mass spectrometry.

This work reported an efficient and accurate liquid chromatography tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of seventeen mycotoxins in Puerariae lobatae radix, a frequently used traditional Chinese medicine (TCM). The effects of four different clean-up methods, including TC-M160, TC-T220, Mycosep 227, and QuEChERS method, on the recoveries of mycotoxins were investigated and compared. Finally, TC-M160 was chosen for better recovery and repeatability for mycotoxins analysis. The analytes were separated on an Agilent ZORBAX SB C18 column (4.6mm×250mm, 5µm particle size), and eluted with a mobile phase consisting of (A) water containing 0.1% formic acid and (B) acetonitrile containing 0.1% formic acid at a flow rate of 0.6mL/min. The separated compounds were detected by a triple quadrupole mass spectrometer operating in positive electrospray ionization with multiple reaction monitoring (MRM) mode. The results of method validation accorded with the requirement of analytical method for mycotoxins in COMMISSION REGULATION (EC) No 401/2006. The developed method was successfully applied for determination of mycotoxins in seventeen batches of Puerariae lobatae radix collected from different provinces of China. Three batches of them were found with contamination of mycotoxins AFB1 at (0.751±0.176)µg/kg, T-2 at (1.10±0.01)µg/kg, and T-2 at (0.853±0.044)µg/kg, respectively. The results demonstrated that the proposed method was suitable for monitoring mycotoxins residues in Puerariae lobatae radix.