Screening the Q-markers of TCMs from RA rat plasma using UHPLC-QTOF/MS technique for the comprehensive evaluation of Wu-Wei-Wen-Tong Capsule.

The appropriate selection of quality marker (Q-marker) for performing the comprehensive quality evaluation of traditional Chinese medicines (TCMs) has much more significance. Wu-Wei-Wen-Tong Capsule (WWWTC), a TCMs prescription, is mainly utilized to treat rheumatoid arthritis (RA) in China. However, the comprehensive quality control for WWWTC has not been achieved because of lacking system analysis for the Q-marker. In this study, a dual wavelength, 203 and 270 nm, was selected based on the feature of 15 Q-markers, and a reliable UHPLC-UV fingerprinting approach was established, achieving the comprehensive quality evaluation of WWWTC. First, we identified 91 prototypes in rat plasma after administering a set amount of WWWTC by using UHPLC-QTOF/MS technique and selected them as the candidate Q-markers. Next, based on the "five principles" of Q-marker selection, 15 absorbed components among them including coumarin, cinnamic acid, cinnamaldehyde, cinnamic alcohol, and 2-methoxycinnamaldehyde derived from Monarch medicine of Cmnamomi Mmulus; epimedin C, icariin, baohuoside I, and anhydroicaritin derived from Monarch medicine Epimedii Folium; germacrone, the sesquiterpene compound in Minister medicine Rhizoma Wenyujin Concisum; pachymic acid, the tetracyclic triterpenoid acids in Assistant medicine Poria; baicalin, baicalein, wogonin, and wogonoside in Guide medicine Scutellariae Radix, respectively, were seriously chosen as the Q-markers, indicating preferable pharmacological effect on RA, characterization of transitivity and traceability as well as measurable components in WWWTC. The effective and meaningful strategy displayed a unique perspective for the exploration of Q-markers in the quality evaluation and further ensured efficacy and safety of the TCMs.

Comparison of the Level of Free Hexafluoro-isopropanol in Adults' Blood and the Incidence of Emergence Agitation After Anesthesia With Different Concentrations of Sevoflurane in Laparoscopic Gastrointestinal Surgery: A Randomized Controlled Clinical Trial.

PURPOSE: The aim of the study is to compare the free hexafluoro-isopropanol (HFIP) concentration in adults' blood and the incidence of emergence agitation (EA) after inhaled different concentrations of sevoflurane. METHODS: Sixty adult patients planning to undergo laparoscopic gastrointestinal surgery were randomly assigned to 3 groups. Each group received sevoflurane as the volatile anesthetic at different concentrations: 0.5 minimum alveolar concentration (MAC), 1.0 MAC, and 1.5 MAC. The use of sevoflurane was continued until the end of surgery. Venous blood samples were obtained at 30, 60, 120, and 180 minutes after starting the use of sevoflurane and subsequently at 60, 180, and 300 minutes after discontinuation of volatile anesthetic administration. Blood concentrations of sevoflurane and free HFIP were determined using gas chromatography. The recovery time and the incidence of EA at different time points were evaluated among the 3 groups. FINDINGS: Changes in the blood concentrations of sevoflurane and free HFIP during and after the use of sevoflurane were similar in all 3 groups. The peak blood concentration of free HFIP occurred 60 minutes after onset of sevoflurane anesthesia in all 3 groups (P < 0.05). The lowest level of free HFIP and the longest recovery time were found in the 1.5-MAC group (P < 0.05). No significant difference was found in the incidence of EA or moderate pain among the 3 groups during recovery. IMPLICATIONS: The generation of HFIP would be inhibited when the inhaled sevoflurane concentration increased to 1.5 MAC. However, the incidence of EA during recovery had nothing to do with the inhaled different sevoflurane concentrations (within 1.5 MAC) in adults. ChicCTR.org identifier: ChiCTR-IPD-17011558.

Sevoflurane for procedural sedation in critically ill patients: A pharmacokinetic comparative study between burn and non-burn patients.

BACKGROUND: Sevoflurane has anti-inflammatory proprieties and short lasting effects making it of interest for procedural sedation in critically ill patients. We evaluated the pharmacokinetics of sevoflurane and metabolites in severely ill burn patients and controls. The secondary objective was to assess potential kidney injury. METHODS: Prospective interventional study in a burn and a surgical intensive care unit; 24 mechanically ventilated critically ill patients (12 burns, 12 controls) were included. The sevoflurane was administered with an expired fraction target of 2% during short-term procedural sedation. Plasma concentrations of sevoflurane, hexafluoroisopropanolol (HFIP) and free fluoride ions were recorded at different times. Kinetic Pro (Wgroupe, France) was used for pharmacokinetic analysis. Kidney injury was assessed with neutrophil gelatinase-associated lipocalin (NGAL). RESULTS: The mean total burn surface area was 36±11%. The average plasma concentration of sevoflurane was 70.4±37.5mg·L-1 in burns and 57.2±28.1mg·L-1 in controls at the end of the procedure (P=0.58). The volume of distribution was higher (46.8±7.2 vs 22.2±2.50L, P<0.001), and the drug half-life longer in burns (1.19±0.28h vs 0.65±0.04h, P<0.0001). Free metabolite HFIP was higher in burns. Plasma fluoride was not different between burns and controls. NGAL did not rise after procedures. CONCLUSION: We observed an increased volume of distribution, slower elimination rate, and altered metabolism of sevoflurane in burn patients compared to controls. Repeated use for procedural sedation in burn patients needs further evaluation. No renal toxicity was detected. TRIAL REGISTRY NUMBER: ClinicalTrials.gov Identifier NCT02048683.

An isotope-dilution UPLC-MS/MS technique for the human biomonitoring of the internal exposure to glycidol via a valine adduct at the N-terminus of hemoglobin.

Fatty acid esters of glycidol (glycidyl esters) are processing contaminants generated as a byproduct of the industrial deodorization of vegetable oils and fats. Oral intake of glycidyl esters leads to the release of glycidol in the gastrointestinal tract. Glycidol is carcinogenic, genotoxic and teratogenic in rodents. It is rated as probably carcinogenic to humans (IARC group 2A). The determination of internal exposure of glycidol may support the assessment of the possible human health risks related to glycidyl ester intake. For this purpose, hemoglobin adducts of glycidol may be suitable biomarkers reflecting the cumulative exposure of up to four months. We applied a modified Edman degradation to assess the glycidol adduct at the N-terminal valine, N-(2,3-dihydroxypropyl)-valine (2,3-diHOPr-Val), of hemoglobin. The modified valine was cleaved with fluorescein-5-isothiocyanate (FITC), resulting in the formation of N-(2,3-dihydroxypropyl)-valine fluorescein thiohydantoin (DHP-Val-FTH). An isotope-dilution technique was developed for the quantification of the thiohydantoin analyte by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and DHP-Val-d7-FTH as reference standard. The limit of detection was 4 fmol DHP-Val-FTH per injection corresponding to 0.7pmol 2,3-diHOPr-Val/g hemoglobin. The adduct levels in blood samples of 12 non-smoking participants were in the range of 2.2-4.9pmol 2,3-diHOPr-Val/g hemoglobin. The current work presents the first isotope-dilution technique using UPLC-MS/MS for the quantification of 2,3-diHOPr-Val at the N-terminus of hemoglobin as a sensitive and convenient alternative to earlier GC-MS methods.

Orally administered glycidol and its fatty acid esters as well as 3-MCPD fatty acid esters are metabolized to 3-MCPD in the F344 rat.

IARC has classified glycidol and 3-monochloropropane-1,2-diol (3-MCPD) as group 2A and 2B, respectively. Their esters are generated in foodstuffs during processing and there are concerns that they may be hydrolyzed to the carcinogenic forms in vivo. Thus, we conducted two studies. In the first, we administered glycidol and 3-MCPD and associated esters (glycidol oleate: GO, glycidol linoleate: GL, 3-MCPD dipalmitate: CDP, 3-MCPD monopalmitate: CMP, 3-MCPD dioleate: CDO) to male F344 rats by single oral gavage. After 30 min, 3-MCPD was detected in serum from all groups. Glycidol was detected in serum from the rats given glycidol or GL and CDP and CDO in serum from rats given these compounds. In the second, we examined if metabolism occurs on simple reaction with rat intestinal contents (gastric, duodenal and cecal contents) from male F344 gpt delta rats. Newly produced 3-MCPD was detected in all gut contents incubated with the three 3-MCPD fatty acid esters and in gastric and duodenal contents incubated with glycidol and in duodenal and cecal contents incubated with GO. Although our observation was performed at 1 time point, the results showed that not only 3-MCPD esters but also glycidol and glycidol esters are metabolized into 3-MCPD in the rat.

Characterization of glycidol-hemoglobin adducts as biomarkers of exposure and in vivo dose.

Hemoglobin adducts have been used as biomarkers of exposure to reactive chemicals. Glycidol, an animal carcinogen, has been reported to form N-(2,3-dihydroxy-propyl)valine adducts to hemoglobin (diHOPrVal). To support the use of these adducts as markers of glycidol exposure, we investigated the kinetics of diHOPrVal formation and its elimination in vitro and in vivo. Five groups of rats were orally administered a single dose of glycidol ranging from 0 to 75mg/kg bw, and diHOPrVal levels were measured 24h after administration. A dose-dependent increase in diHOPrVal levels was observed with high linearity (R(2)=0.943). Blood sampling at different time points (1, 10, 20, or 40days) from four groups administered glycidol at 12mg/kg bw suggested a linear decrease in diHOPrVal levels compatible with the normal turnover of rat erythrocytes (life span, 61days), with the calculated first-order elimination rate constant (kel) indicating that the diHOPrVal adduct was chemically stable. Then, we measured the second-order rate constant (kval) for the reaction of glycidol with N-terminal valine in rat and human hemoglobin in in vitro experiments with whole blood. The kval was 6.7±1.1 and 5.6±1.3 (pmol/g globin per µMh) in rat and human blood, respectively, indicating no species differences. In vivo doses estimated from kval and diHOPrVal levels were in agreement with the area under the (concentration-time) curve values determined in our earlier toxicokinetic study in rats. Our results indicate that diHOPrVal is a useful biomarker for quantification of glycidol exposure and for risk assessment.

Relative oral bioavailability of glycidol from glycidyl fatty acid esters in rats.

In order to quantify the relative bioavailability of glycidol from glycidyl fatty acid esters in vivo, glycidyl palmitoyl ester and glycidol were orally applied to rats in equimolar doses. The time courses of the amounts of glycidol binding to hemoglobin as well as the excretion of 2,3-dihydroxypropyl mercapturic acids were determined. The results indicate that glycidol is released from the glycidyl ester by hydrolysis and rapidly distributed in the organism. In relation to glycidol, there was only a small timely delay in the binding to hemoglobin for the glycidol moiety released from the ester which may be certainly attributed to enzymatic hydrolysis. In both cases, however, an analogous plateau was observed representing similar amounts of hemoglobin binding. With regard to the urinary excretion of mercapturic acids, also similar amounts of dihydroxypropyl mercapturic acids could be detected. In an ADME test using a virtual double tag (³H, ¹4C) of glycidyl palmitoyl ester, a diverging isotope distribution was detected. The kinetics of the ¹4C-activity reflected the kinetics of free glycidol released after hydrolysis of the palmitoyl ester. In view of this experimental data obtained in rats, it is at present justified for the purpose of risk assessment to assume complete hydrolysis of the glycidyl ester in the gastrointestinal tract. Therefore, assessment of human exposure to glycidyl fatty acid ester should be regarded as an exposure to the same molar quantity of glycidol.

Species differences in toxicokinetic parameters of glycidol after a single dose of glycidol or glycidol linoleate in rats and monkeys.

Glycidol fatty acid esters (GEs) have been identified as contaminants in refined edible oils. Although the possible release of glycidol (G) from GEs is a concern, little is known about the conversion of GEs to G in the human body. This study addressed the toxicokinetics of glycidol linoleate (GL) and G in male Crl:CD(SD) rats and cynomolgus monkeys. Equimolar amounts of GL (341 mg/kg) or G (75 mg/kg) were administered by gavage to each animal. G was found in both species after the G and GL administration, while plasma GL concentrations were below the lower limit of quantification (5 ng/ml) in both species. In rats, the administration of GL or G produced similar concentration-time profiles for G. In monkeys, the C(max) and AUC values after GL administration were significantly lower than those after G administration. The oral bioavailability of G in monkeys (34.3%) was remarkably lower than that in rats (68.8%) at 75 mg/kg G administration. In addition, plasma G concentrations after oral administration at three lower doses of GL or G were measured in both species. In monkeys, G was detected only at the highest dose of G. In contrast, the rats exhibited similar plasma G concentration-time profiles after GL or G administration with significantly higher G levels than those in monkeys. In conclusion, these results indicate that there are remarkable species differences in the toxicokinetics of GEs and G between rodents and primates, findings that should be considered when assessing the human risk of GEs.

Determination of sevoflurane and its metabolite hexafluoroisopropanol by direct injection of human plasma into gas chromatography-tandem mass spectrometry.

The developed method for trace analysis of volatile components in plasma allows direct injection of up to 150 samples to the GC-MS/MS system without injector cleaning. This method requires no modification of plasma and the working environment does not interfere with the determination of these analytes. The method allows simultaneous quantification of non-polar sevoflurane and its polar metabolite hexafluoroisopropanol (free, unconjugated form). It is characterized by high repeatability and sensitivity with the detection limit of 0.009 mg L(-1) for sevoflurane and 0.018 mg L(-1) for hexafluoroisopropanol and the linear range 0.050-150 mg L(-1). The method was used to determine the concentration of sevoflurane and hexafluoroisopropanol in plasma samples of 7 patients undergoing general anesthesia with sevoflurane. The average concentration of sevoflurane and free hexafluoroisopropanol was 57.2 mg L(-1) and 0.39 mg L(-1), respectively. The method can be applied for clinical monitoring, as well as for analytical toxicology.

Measurement of glycidol hemoglobin adducts in humans who ingest edible oil containing small amounts of glycidol fatty acid esters.

Hemoglobin (Hb) adducts are frequently used to address and/or monitor exposure to reactive chemicals. Glycidol (G), a known animal carcinogen, has been reported to form Hb adducts. Here, we measure G adduct levels in humans who daily ingest DAG oil, an edible oil consisting mainly of diacylglycerol. Since DAG oil contains a small amount of glycidol fatty acid esters (GEs), possible exposure to G released from GEs has been raised as a possible concern. For measurement of Hb adducts, we employed the N-alkyl Edman method reported by Landin et al. (1996) using gas chromatography-tandem mass spectrometry with minor modifications to detect G-Hb adducts as N-(2,3-dihydroxy-propyl)valine (diHOPrVal). Blood samples were collected from 7 DAG oil users and 6 non-users, and then G-Hb adduct levels were measured. G-Hb adducts were detected in all samples. The average level of diHOPrVal was 3.5±1.9pmol/g globin in the DAG oil users and 7.1±3.1pmol/g globin in the non-users. We conclude that there is no increased exposure to G in individuals who daily ingest DAG oil.

Simple assay of plasma sevoflurane and its metabolite hexafluoroisopropanol by headspace GC-MS.

The anesthetic sevoflurane can now be delivered over periods of up to 48h using a newly developed medical system, the AnaConDa (anesthetic conserving device). Lack of pharmacokinetic data on sevoflurane and its main metabolite (hexafluoroisopropanol, HFIP) in this indication prompted us to develop a headspace GC-MS method to quantify the two substances. The only previously published method for assaying the two substances could not be adapted to our study since it uses expensive and rarely employed system components together with toxic carbon disulfide as a dilution solvent. The method developed is straightforward and uses the relatively non-toxic solvent undecane as dilution solvent and chloroform as internal standard. The method is linear for a concentration range of 1-150microg/ml, and presents high accuracy and precision. LOD and LOQ are 0.2 and 1microg/ml, with a short analysis time (7.6 min for a single analysis). The method was applied to determine the plasma levels of sevoflurane and HFIP in six patients under 48-h anesthetic sedation delivered via the AnaConDa system. Average sevoflurane and HFIP concentrations plateaued at 75 and 4microg/ml, respectively. Sevoflurane quickly tailed off after inhalation was stopped, and HFIP levels remained low.

Study of the metabolism of estragole in humans consuming fennel tea.

The metabolism of the potent carcinogen estragole was investigated in humans after consumption of fennel tea by analyses of its metabolites in blood plasma and urine. Stable isotope dilution assays based on LC-MS/MS detection revealed that 1'-hydroxylation of estragole happened very fast as the concentration of conjugated 1'-hydroxyestragole in urine peaked after 1.5 h, whereas it was no longer detectable after 10 h. Besides the formation of less than 0.41% conjugated 1'-hydroxyestragole of the estragole dose administered, the further metabolite p-allylphenol was generated from estragole in a higher percentage (17%). Both metabolites were also detected in blood plasma in less than 0.75-2.5 h after consumption of fennel tea. In contrast to this, no estragole was present in these samples above its detection limit. From the results, it can be concluded that an excess of the major fennel odorant trans-anethole principally does not interfere with estragole metabolism, whereas influences on the quantitative composition of metabolites cannot be excluded. The presence of a sulfuric acid conjugate of estragole could not be confirmed, possibly due to its high reactivity and lability.

Dose-dependent liver regeneration in chloroform, trichloroethylene and allyl alcohol ternary mixture hepatotoxicity in rats.

The present study was designed to examine the hypothesis that liver tissue repair induced after exposure to chloroform (CF) + trichloroethylene (TCE) + allyl alcohol (AA) ternary mixture (TM) is dose-dependent similar to that elicited by exposure to these compounds individually. Male Sprague Dawley (S-D) rats (250-300 g) were administered with fivefold dose range of CF (74-370 mg/kg, ip), and TCE (250-1250 mg/kg, ip) in corn oil and sevenfold dose range of AA (5-35 mg/kg, ip) in distilled water. Liver injury was assessed by plasma alanine amino transferase (ALT) activity and liver tissue repair was measured by (3) H-thymidine incorporation into hepatonuclear DNA. Blood and liver levels of parent compounds and two major metabolites of TCE [trichloroacetic acid (TCA) and trichloroethanol (TCOH)] were quantified by gas chromatography. Blood and liver CF and AA levels after TM were similar to CF alone or AA alone, respectively. However, the TCE levels in blood and liver were substantially decreased after TM in a dose-dependent fashion compared to TCE alone. Decreased plasma and liver TCE levels were consistent with decreased production of metabolites and elevated urinary excretion of TCE. The antagonistic interaction resulted in lower liver injury than the summation of injury caused by the individual components at all three-dose levels. On the other hand, tissue repair showed a dose-response leading to regression of injury. Although the liver injury was lower and progression was contained by timely tissue repair, 50% mortality occurred only with the high dose combination, which is several fold higher than environmental levels. The mortality could be due to the central nervous system toxicity. These findings suggest that exposure to TM results in lower initial liver injury owing to higher elimination of TCE, and the compensatory liver tissue repair stimulated in a dose-dependent manner mitigates progression of injury after exposure to TM.