AIM: To study the pharmacokinetics of phenolic acids from Mailuoning injection in rats. METHODS: SD rats were given a single i.v. administration dose of Mailuoning injection 10 mL/kg, plasma and urine were collected before and after injection. Phenolic acid components in plasma and urine were measured by LC/MS. Pharmacokinetic parameters were determined from the plasma concentration-time data and urinary excretion-time data with the DAS software package. RESULTS: After i.v. of Mailuoning injection, chlorogenic acid (CGA), 1, 5-dicaffeylquinic acid (1,5-DCQA), 3, 4-dicaffeylquinic acid (3,4-DCQA), 3, 5-dicaffeylquinic acid (3,5-DCQA) and caffeic acid (CA) were quickly excrectioned. The t1/2 of CGA, 1,5-DCQA, 3,4-DCQA, 3,5-DCQA and CA were 0.649, 0.334, 0.479, 0.486 and 0.330 h, respectively. AUC0-∞ were (22.522±2.716), (0.353±0.062), (3.620±1.246), (5.287±1.627) and (2.257±0.360) mg·L-1·h, respectively. After i.v. of Mailuoning injection, CGA, 1,5-DCQA, 3,4-DCQA, 3,5-DCQA and CA can all be detected in the urine. The amounts of CGA, 1,5-DCQA, 3,4-DCQA, 3,5-DCQA and CA excreted from urine during 0-24 h were (122.22±26.49)%, (3.30±1.26)%, (0.24±0.11)%, (1.93±0.77)% and (18.61±4.99)% of dose given in rats, respectively. CONCLUSION: After i.v. of Mailuoning injection, phenolic acids can be excreted quickly. Only a small quantity of 1,5-DCQA, 3,4-DCQA, 3,5-DCQA and CA were excreted from urine. 3,4-DCQA and 3,5-DCQA may be metabolized into CGA in the rat plasma.

Objectives: To determine the regulation effects of recombinant human growth hormone(rhGH) on dipeptide transport(PepT1) in normal and severe scalded rats. Methods: Male Sprague Dawley rats inflicted by 30% total body surface area ( TBSA) Ⅲ degree scalding were employed as the model.The rhGH was used in this study with the dose of 2 U/(kg?d). An everted sleeve of intestine was incubated in Kreb’s solution with radioactive dipeptide ( 3 H Glycylsarcosine, 3 H Gly Sar, 10 ?Ci / ml) at 37℃ for 15 min to measure the effects of uptake and transport of PepT1 of small intestinal epithelial cells in normal and severe scalded rats. Results: The transport of dipeptide in normal rats with injection of rhGH was not significantly increased compared with controls ( P =0.192 6) while the uptake was significantly increased compared with controls ( P = 0.025 3 ). The transport and uptake of PepT1 in scalded rats with injection of rhGH were significantly increased compared with controls( P = 0.008 2 and 0.039 1). Conclusions: The effects of uptake and transport of dipeptide transporters in small intestinal epithelial cells with severe injury were markedly upregulated by rhGH.

Aim To establish an analytical method for determination of compound G004 concentration in plasma and investigate its application to pharmacokinetics and absolute bioavailability in rats.Methods 5.0 and 2.5 mg?kg~(-1) compound G004 were given via ig and iv respectively to SD rats.Blood samples were collected at various time points after administration.Plasma concentration of compound G004 in rats was determined by LC-ESI-MS.Pharmacokinetic parameters were calculated by DAS program and absolute bioavailability was also calculated.Results The method was linear over the range of 0.02～5 mg?L~(-1)(r~2=0.9995).The recovery of compound G004 in rat plasma was more then 87%.Intra-and inter-day precision,expressed as the relative standard deviation(RSD) was less than 15%.After iv compound G004,the main pharmacokinetic parameters T_(2),CLs,V_d,AUC_((0-∞)) were(1.91?0.65) h,(0.36?0.22) L?h~(-1),(0.78?0.36) L ?kg~(-1),(9.52?3.53) mg?L~(-1)?h~(-1) respectively.The major pharmacokinetic parameters T_(max),C_(max),T_(2),AUC_((0-∞)),MRT_((0-12h)) were 0.83 h,(3.33?0.80) mg?L~(-1),(1.77?0.21) h,(10.04?2.43) mg?L~(-1)?h~(-1) and(2.75?0.31)h after ig compound G004.The absolute bioavailability was 52.69% after correction of dosage.Conclusion The method is sensitive and specific which is applicable to pharmacokinetic analysis of compound G004 in rats.

A qualitative analytical method of liquid chromatography coupled with ion trap time-of-flight mass spectrometry (LC-IT-TOF/MS) was developed for identification of major constituents in propolis from China (Shandong).The LC-IT-TOF-MS was performed on a Shim-pack VP-ODS column (2.0 mm× 150 mm,5 μm) with the mobile phase consisting of acetonitrile and water containing 0.2％ formic acid in gradient mode,and the flow rate was set at 0.3 mL/min.Negative ion mode was used for IT-TOF-MS.According to the accurate molecular weight,MS fragment pathway,comparison with the retention time of reference compounds,total 31 compounds,including twenty-five phenolic acids and six flavonoids were identified.The LC-IT-TOF-MS qualitative analysis method can be used for analyzing major components of propolis quickly and accurately.

Drug metabolism studies, including in vivo and in vitro metabolism studies, are significant in the design of candidate compounds and screening of lead compounds at drug discovery/development stages. Compared with in vivo metabolism studies, in vitro metabolism studies have the advantages of rapidity, simplicity, without consumption of large amounts of samples and animals. Moreover, it is convenient for researchers to observe the selective interaction between compound and target. Therefore, in vitro metabolism studies are appropriate for high throughput screening of compounds which are lack of metabolism information and have been widely used during drug discovery stages. This article briefly introduced the application of in vitro drug metabolism studies based on the metabolic stability, reaction phenotyping and metabolic drug-drug interactions, aiming to raise valuable evaluation strategies for innovative drug discovery in China.

The aim of the study is to evaluate the effects of the single and mixed decoction of Thallus laminariae (kelp) and Glycyrrhiza glabra (licorice) on the metabolism and their difference. The mixed decoction of kelp and licorice and the single decoction were made and intragastrically administered to the SD rats. The effect on system metabolism, the toxicity of liver and kidney were assessed by GC-MS profiling of the endogenous molecules in serum, routine biochemical assays and histographic inspection of tissues from SD rats, separately. The mixed decoction of kelp and licorice induced more obvious pathological abnormalities in SD rats than a single decoction of kelp, while the extracts of licorice did not show any pathological change. Neither the mixed, nor the single decoction showed abnormal histopathology. After intragastric administration of extracts for 5 days, the mixed decoction induced a decrease of ALT (no significant change in the groups of single decoction) and an increase of BUN (so did the single decoction of kelp). Metabolomic profile of the molecules in serum revealed that the metabolic patterns were all obviously affected for the three groups, i.e., the mixed and single decoction of kelp and licorice. The rats given with the single decoction of kelp showed a similar pattern to that of the mixed decoction, indicating that the kelp primarily contributed the perturbation of metabolism for the mixed decoction. All three groups induced a decrease of branched chain amino acids, TCA cycle intermediates and glycolysis intermediates (e.g., pyruvic acid and lactic acid) and an increase of 3-hydroxybutyric acid. Kelp decoction showed stronger potential in reducing TCA cycle intermediates and glycolysis intermediates than the other two groups, while the levels of branched chain amino acids were the lowest after licorice extracts were given. These results suggested that the effect of the mixed decoction on metabolism was closely associated with both kelp and licorice. The continuous administration of single decoction of kelp and the mixed decoction of licorice and kelp resulted in pathological abnormalities in kidney of SD rats. The mixed decoction of kelp and licorice distinctly perturbed sera molecules and hence system metabolism, which showed associated with those of kelp and licorice. Although the metabolic effect was associated with both kelp and licorice, the results suggested kelp contributed to it primarily.

To investigate the influential mechanism of total flavonoids from Abelmoschus Manihot (HKZ) on cytochrome P450 (CYP450) isoforms in human liver microsomes and to verify its effect on the most significantly inhibited subtype CYP2C9 in rats.The inhibitory effects of HKZ on human CYP3A4, CYP2C9, CYP2C19, CYP2E1, CYP1A2 and CYP2D6 were evaluated through the cocktail method using ultra-performance liquid chromatography tandem mass spectrometry, then its inhibitory mechanism was investigated and kinetic parameters of enzyme inhibition were calculated By comparing the pharmacokinetic behaviors of tolbutamide after single or multiple administration of 200 mg/kg HKZ and equal dose of CMC-Na in rats, the effects of HKZ on CYP2C11 enzyme (CYP2C9 isoenzyme) was estimated.The results indicated the significant inhibitory effect of HKZ on CYP2C9 and CYP2E1 with IC50 of 3.22 and 8.64 μg/mL, respectively. Also, it showed certain inhibitory ability on other isoforms with IC50 of 20-30 μg/mL.As demonstrated, HKZ may not be a time-dependent inhibitor which competitively inhibited CYP2E1 and CYP2C9 with Ki of 3.84 and 6.33 μg/mL.In contrast, it showed noncompetitive inhibition on CYP3A4 mediated testosterone-6β-hydroxylation and midazolam-4-hydroxylation reaction with Ki of 7.37 and 3.32 μg/mL.It was also a noncompetitive inhibitor of CYP1A2, CYP2D6 and CYPC219 with Ki values of 8.66, 11.49 and 21.94 μg/mL. HKZ did not change the pharmacokinetic parameters of CYP2C11 probe substrate tolbutamide in rat, but it affected the AUC0-t, cmax of 4-hydroxytolubutamide (P < 0.05). Therefore, drug-drug interaction mediated by CYP450 should be considered in clinical study.

To establish a quantitative LC-MS/MS method for the simultaneous detection of components of Erlong Zuoci Pill in rat plasma: verbascoside, oxypaeoniflorin, echinacoside and benzoylpaeoniflorin, and to evaluate the pharmacokinetic characteristics of Erlong Zuoci Pill in rats, plasma samples were purified by protein precipitation using methanol as a protein precipitant.Methanol was used as the organic phase and aqueous solution containing 0.1% formic acid was used as the water phase.The quantitative analysis method of verbascoside, oxypaeoniflorin, echinacoside and benzoylpaeoniflorin was established in negative ion mode, and the validation of bioanalytical method was carried out.Healthy SD rats were selected, and 20 mL/kg (equivalent to the original drug 10 g/kg dose) of Erlong Zuoci Pill extract was administered by intragastric administration.The plasma concentration of the target compounds at different time intervals after administration was determined using the established method, and the pharmacokinetic parameters was calculated by the Phoenix WinNonlin8.3 software using the non-compartmental model.The method validation results showed that verbascoside (r = 0.993 7) and oxypaeoniflorin (r = 0.994 6) had good linear relationship in the concentration range of 0.5-50 ng/mL, echinacoside (r = 0.993 6) and benzoylpaeoniflorin (r = 0.992 6) had good linear relationship in the concentration range of 1-100 ng/mL.The relative standard deviations of the inter- and intra- batch precision of the four compounds were all less than 15%, and the inter- batch and intra- accuracies were between 85% and 115%.Extraction recovery, matrix effect and stability met the relevant requirements.After a single gavage of Erlong Zuoci Pill extract in rats, all the four compounds were rapidly absorbed and eliminated.Oxypaeoniflorin, echinacoside, and benzoylpaeoniflorin showed two peaks in their drug concentration-time curves.Compared with the other three compounds, oxypaeoniflorin has the highest concentration in rat plasma with cmax1 of (24.40 ± 4.78) ng/mL and cmax2 of (22.50 ± 2.70) ng/mL. The results show that the validation results of this method are in line with the guiding principles of biological sample analysis methods, and it can be used to evaluate the pharmacokinetic characteristics of Erlong Zuoci Pill extract in rats.

To the present study aimed to investigate the protective effects of Erlong Zuoci Pills on oxidative stress induced by hydrogen peroxide (H2O2) in House Ear Institute-Organ of Corti 1 (HEI-OC1) and to explore the mechanism by cellular metabolomics. There were 6 groups in the experiment: the control group, model group, three dose groups of ELZC (low, medium, and high), and positive control ascorbic acid group. The oxidative stress injury model was established in the HEI-OC1 by inducing 0.9 mmol/L H2O2 for 12 h. The proliferation of HEI-OC1 cells was observed by CCK-8 assay; the contents and activity of lactate hydrogenase (LDH), reactive oxygen species (ROS), and superoxide dismutase (SOD) in HEI-OC1 cells were detected by corresponding kits. Finally, the endogenous substances of cells were analyzed from the perspective of metabolomics. Compared with the model group, ELZC groups could significantly increase the cell proliferation rate after administration. Moreover, they could also ameliorate the increase of ROS and LDH content and the decrease of antioxidant enzyme SOD caused by H2O2. Metabolomic results revealed significant differences among multiple groups in the scores of partial least squares discriminant analysis. The ELZC group could relocate the model group back to the control group. The metabolic regulation of ELZC on oxidative stress in HEI-OC1 cells mainly affects nucleotide metabolism and amino acid metabolism. In summary, the results indicate that ELZC exhibits protective effects on H2O2-induced oxidative stress in HEI-OC1 cells. Additionally, this protective effect may be produced by increasing the content of amino acids such as uridine and phenylalanine, thereby regulating pathways such as pyrimidine metabolism, phenylalanine metabolism, biosynthesis of phenylalanine, tyrosine, and tryptophan, and histidine metabolism.

Quantitative proteomics is a mass spectrometry-based toolkit used to analyze and quantify entire proteins contained in whole cells, tissues or organisms. It has become an increasingly important element in exploring the mechanism of various biological processes such as discovering novel biomarkers and unknown drug targets. Emerging advances in biological mass spectrometry instrumentation and data acquisition methodologies have provided a state-of-the-art platform for protein quantification, prompting the research of proteomics evolving from the simple qualitative to the accurate quantitative approach. This review aims to introduce the most recent advancements in mass spectrometry instrumentation and methodologies of data acquisition, focusing on their characteristics and applying fields. It also highlights several significant applications of biological mass spectrometry in pharmaceutical research such as quantifitation of drug transporters and metabolizing enzymes, and pharmacokinetic study of therapeutic peptides and proteins.