ABSTRACT
OBJECTIVES@#To analyse the metabolic changes in urine of rats with brodifacoum intoxication, and to reveal the molecular mechanism of brodifacoum-induced toxicity on rats.@*METHODS@#By establishing a brodifacoum poisoning rats model, the urine metabolic profiling data of rats were acquired using high performance liquid chromatography-time of flight mass spectrometry （HPLC-TOF-MS）. The orthogonal partial least squares analysis-discrimination analysis （OPLS-DA） was applied for the multivariate statistics and the discovery of differential metabolites closely related to toxicity of brodifacoum.@*RESULTS@#OPLS-DA score plot showed that the urinary metabolic at different time points before and after drug administration had good similarity within time period and presented clustering phenomenon. Comparing the urine samples of rats before drug administration with which after drug administration, twenty-two metabolites related to brodifacoum-induced toxicity were selected.@*CONCLUSIONS@#The toxic effect of brodifacoum worked by disturbing the metabolic pathways in rats such as tricarboxylic cycle, glycolysis, sphingolipid metabolism and tryptophan metabolism, and the toxicity of brodifacoum is characterized of accumulation effect. The metabonomic method based on urine HPLC-TOF-MS can provide a novel insight into the study on molecular mechanism of brodifacoum-induced toxicity.
Subject(s)
Animals , Rats , 4-Hydroxycoumarins/toxicity , Biomarkers/urine , Chromatography, High Pressure Liquid/methods , Mass Spectrometry , Metabolomics/methods , Principal Component AnalysisABSTRACT
A method of high performance liquid chromatography coupled with time-of-flight mass spectrometry was used to detect the endogenous metabolites changes in plasma of normal rats, rats of dampness stagnancy due to spleen deficiency and Astragalus flavone component intervention rats. Metabolism map of rat plasma was obtained and the mechanism of Astragalus flavonoids on dampness stagnancy due to spleen deficiency was studied. Rat model with dampness stagnancy due to spleen deficiency was established by high fat and low protein diet plus load swimming. Liquid chromatography tandem mass spectrometry was used for the analysis of rat plasma sample, and 0.05％ formic acid water with 0.05％ formic acid acetonitrile as the mobile phase was applied in gradient elution with Halo C18 chromatographic column. In this study, partial least squares discriminant analysis and variance analysis were used to screen the potential biomarkers, it was found that the metabolic profile of the Astragalus flavonoids was different from that of the model group, which was close to that of the normal group. A total of 11 potential biomarkers were identified, including glycerol phospholipids, sphingolipids, amino acids, and so on. The metabolic pathways of biomarkers including three tricarboxylic acid cycle, glycerol phospholipid metabolism, fatty acid metabolism, amino acid metabolism and so on, which mainly related to energy metabolism and fat metabolism in the body. Related indexes of rats with syndrome of spleen deficiency of water and dampness were significantly callback after Astragalus flavone intervention, including macro indicators such as body weight, independent activities and micro indicators such as metabolic markers, blood lipids and others. The result showed that Astragalus flavonoids played the role of strengthening the spleen and draining the water mainly through regulating the energy metabolism, fat metabolism and so on.
ABSTRACT
Objective To use high-performance liquid chromatography-time of flight mass spectrometry (HPLC-TOF/ MS) for examining the steroidal saponins in rat urine after oral administration of Paris polyphylla extract, so as to lay a foundation for studying the metabolism of steroidal saponins in vivo. Methods SD rats were administered with an oral dose of 1 6 g Paris polyphylla extracts/kg body weight. The urine samples were collected 24 h after administration by oral gavage. The sample analysis was carried out on a reverse phase MG-C18 column (3. 0 mm× 100 3. 0μm) using a gradient mobile phase system of acetonitrile-water containing 0. 1% formic acid. TOF/MS was applied for qualitative analysis under positive and negative ion modes. The steroidal saponins in rat urine were identified by using the accurate molecular weight obtained by TOF/ MS and formula database. Results A total of 20 steroidal saponins were identified in the rat urine, and two pairs of isomers were deduced through their fragment ions and standards: polyphyllin VI and pennogenin-3-0-α-L-rhamnopyranosyl(l →4)-α-L-rhamnopyranosyl (1 → 3)-[-α--rhamnopyranosyl (1 → 2)]-β-D-glucopyranoside; and gracillin and pennogenin-3-O-α-L-rhamnopyranosyKl → 4)-α-L-rhamnopyranosyl (1 → 4)-β-D-glucopyranoside. Conclusion The established analysis method is accurate, reliable for identifying steroidal saponins in vivo, which paves a way for further pharmacokinetics and pharmacodynamics study of Paris polyphylla.
ABSTRACT
Objective To use high-performance liquid chromatography-time of flight mass spectrometry (HPLC-TOF/ MS) for analyzing the chemical constituents of Fuzhengpingxiao Capsule. Methods The separation was performed on a Agilent Eclipse plus C18 reverse phase column (4. 6 mm×250 mm, 5 μm). The mobile phase consisted of water containing 0. 1% formic acid and acetonitrile was used as gradient elute. The flow rate was 1 ml/min, the post-column split ratio was 3:1, and the temperature of column was 25°C. Time-of-flight mass spectrometer(TOF/MS) and electrospray ion source (ESI) was employed for qualitative analysis under both positive and negative ion mode, and mass scan range was m/z 100-1 100. Results A total of 247 major chemical constituents were identified in Fuzhengpingxiao Capsule by HPLC-TOF/MS, including 168 in positive mode, 103 in negative mode, and 24 in both. The source herb of the components were identified. Conclusion An efficient HPLC-TOF/MS approach has been established for studying the chemical constituents in Fuzhengpingxiao Capsule, which paves a way for the quality control and further in vivo studies of the preparation.