Simultaneous quantitation of acetylsalicylic acid and clopidogrel along with their metabolites in human plasma using liquid chromatography tandem mass spectrometry

Rapid identification of potential nonsteroidal anti-inflammatory drug overdose-induced liver toxicity and prediction of follow-up exposure: Integrating bioanalytical and population pharmacokinetic assay

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most frequently used drugs that can cause liver toxicity. The aim of this study was to integrate bioanalytical and population pharmacokinetic (PopPK) assay to rapidly screen and quantify the concentrations of NSAIDs in plasma and monitor clinical safety. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous quantification of acetaminophen (APAP), flurbiprofen (FLB), aspirin (ASP), and ibuprofen (IBP), four commonly used NSAIDs. The PopPK model of the signature toxicant was analyzed based on the published literature. The LC-MS/MS method was successfully validated and applied to determine NSAID concentrations in patient plasma samples. APAP, ASP, and IBP data were best fitted using a one-compartment model, and FLB data were best fitted using a two-compartment model. Bootstrapping and visual predictive checks suggested that a robust and reliable pharmacokinetic model was developed. A fast, simple, and sensitive LC-MS/MS method was developed and validated for determining APAP, FLB, ASP, and IBP in human plasma. Combined with the PopPK model, this method was applied to rapidly analyze the concentrations of NSAIDs in clinical samples from patients presenting to the emergency department with acute liver dysfunction and monitored NSAIDs clinical safety.

In-vitro and in-vivo metabolism of different aspirin formulations studied by a validated liquid chromatography tandem mass spectrometry method

Low-dose aspirin (ASA) is used to prevent cardiovascular events. The most commonly used formulation is enteric-coated ASA (EC-ASA) that may be absorbed more slowly and less efficiently in some patients. To uncover these "non-responders" patients, the availability of proper analytical methods is pivotal in order to study the pharmacodynamics, the pharmacokinetics and the metabolic fate of ASA. We validated a high-throughput, isocratic reversed-phase, negative MRM, LC-MS/MS method useful for measuring circulating ASA and salicylic acid (SA) in blood and plasma. ASA-d4 and SA-d4 were used as internal standards. The method was applied to evaluate: (a) the "in vitro" ASA degradation by esterases in whole blood and plasma, as a function of time and concentration; (b) the "in vivo" kinetics of ASA and SA after 7 days of oral administration of EC-ASA or plain-ASA (100 mg) in healthy volunteers (three men and three women, 37-63 years). Parameters of esterases activity were Vmax 6.5 ± 1.9 and Km 147.5 ± 64.4 in plasma, and Vmax 108.1 ± 20.8 and Km 803.2 ± 170.7 in whole blood. After oral administration of the two formulations, tmax varied between 3 and 6 h for EC-ASA and between 0.5 and 1.0 h for plain-ASA. Higher between-subjects variability was seen after EC-ASA, and one subject had a delayed absorption over eight hours. Plasma AUC was 725.5 (89.8-1222) for EC-ASA, and 823.1(624-1196) ng h/mL (median, 25-75% CI) for plain ASA. After the weekly treatment, serum levels of TxB2 were very low (< 10 ng/mL at 24 h from the drug intake) in all the studied subjects, regardless of the formulation or the tmax. This method proved to be suitable for studies on aspirin responsiveness.

Simultaneous Quantification of Aspirin, Its Metabolite Salicylic Acid, and Salvianolic Acid B in Human Plasma Using UPLC-MS/MS

Salvianolic acid B is the main active ingredient in salvianolate injection, which is produced by extracting danshen, the most commonly used Chinese herbal medicine for cardiovascular treatment. Clinically, salvianolate injection and aspirin are commonly combined to treat coronary heart diseases in patients with stable angina. To support clinical studies on drug-drug interactions (DDIs) between salvianolate injection and aspirin, a rapid and sensitive UPLC-MS/MS method for the simultaneous determination of aspirin (acetylsalicylic acid), its metabolite salicylic acid, and salvianolic acid B in human plasma was developed. The analytes and internal standard were extracted from the acidified plasma by liquid-liquid extraction with ethyl acetate and then separated by gradient elution with acetonitrile/0.5% formic acid in water on a C18 column. Salvianolic acid B, acetylsalicylic acid, and salicylic acid were quantified in multiple-reaction monitoring mode with negative ion electrospray ionization. The method was fully validated according to the current regulatory guidance for bioanalysis. Calibration curves in the range 5–6000 ng/mL, all with correlation coefficients greater than 0.99, were established using linear regression models for salvianolic acid B and acetylsalicylic acid and a quadratic model for salicylic acid. The validated method was successfully used to measure salvianolic acid B, acetylsalicylic acid, and salicylic acid concentrations in human plasma samples from 16 patients to observe the pharmacokinetic changes caused by DDIs.

Chemical Composition of Tomato Seed Flours, and Their Radical Scavenging, Anti-Inflammatory and Gut Microbiota Modulating Properties

In the current study, the chemical composition and total phenolic content of tomato seed flours, along with potential health beneficial properties, including free radical scavenging capacities, anti-inflammatory capacities, and gut microbiota profile modulation, were examined using two different batches. Eight compounds were identified in the tomato seed flour, including malic acid, 2-hydroxyadipic acid, salicylic acid, naringin, N-acetyl-tryptophan, quercetin-di-O-hexoside, kaempferol-di-O-hexoside, and azelaic acid. The total phenolic contents of tomato seed flour were 1.97-2.00 mg gallic acid equivalents/g. Oxygen radical absorbing capacities (ORAC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacities (DPPH), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical scavenging capacities (ABTS) were 86.32-88.57, 3.57-3.81, and 3.39-3.58 µmoles Trolox equivalents/g, respectively, on a per flour dry weight basis. The mRNA expression of the pro-inflammatory markers, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α), were dose-dependently suppressed by tomato seed flour extracts. The extracts altered five of the eight bacterial phyla and genera evaluated. The results may provide some scientific support for the use of tomato seed flour as value-added food ingredients.

Analysis of Aspirin, Prasugrel and Clopidogrel in Counterfeit Pharmaceutical and Herbal Products: Plackett–Burman Screening and Box–Behnken Optimization

An isocratic reversed-phase high-performance liquid chromatographic method has been developed and validated for the simultaneous determination of aspirin, prasugrel HCl and clopidogrel bisulfate in the presence of clopidogrel-related compound (impurity-A) in focus on counterfeit. This method was used to determine counterfeited antiplatelet drugs in two substandard Indian pharmaceutical products sold on the market in Yemen and two traditional herbal medicines sold on the market in China. Thin layer chromatography and mass spectrometry of counterfeit herbal medicines have additionally been carried out to verify the identification of adulterants. Chromatographic separation was performed on Inertsil ® ODS-3 C18 (4.6 × 250 mm, 5 μm) with isocratic mobile phase elution containing a mixture of acetonitrile: (25 mM) potassium dihydrogen phosphate buffer, pH 2.7 adjusted with 0.1 M o-phosphoric acid (79: 21, v/v), at a flow rate of 1 mL/min and UV detection at 220 nm. Designs of experiment methodology, Plackett–Burman and Box–Behnken designs were used for the screening and optimization of the mobile phase composition. The method validation was also performed in accordance with the International Council on Harmonization (ICH) guidelines. The method developed for routine analysis was found to be sensitive, simple, accurate and highly robust. The results were statistically compared to reference methods using Student’s t-test and variance ratio F-test at P &lt; 0.05.

ASA Suppresses PGE2 in Plasma and Melanocytic Nevi of Human Subjects at Increased Risk for Melanoma

Potential anti-inflammatory and anticarcinogenic effects of aspirin (ASA) may be suitable for melanoma chemoprevention, but defining biomarkers in relevant target tissues is prerequisite to performing randomized controlled chemoprevention trials. We conducted open-label studies with ASA in 53 human subjects with melanocytic nevi at increased risk for melanoma. In a pilot study, 12 subjects received a single dose (325 mg) of ASA; metabolites salicylate, salicylurate, and gentisic acid were detected in plasma after 4-8 h, and prostaglandin E2 (PGE2) was suppressed in both plasma and nevi for up to 24 h. Subsequently, 41 subjects received either 325 or 81 mg ASA (nonrandomized) daily for one week. ASA metabolites were consistently detected in plasma and nevi, and PGE2 levels were significantly reduced in both plasma and nevi. Subchronic ASA dosing did not affect 5" adenosine monophosphate-activated protein kinase (AMPK) activation in nevi or leukocyte subsets in peripheral blood, although metabolomic and cytokine profiling of plasma revealed significant decreases in various (non-ASA-derived) metabolites and inflammatory cytokines. In summary, short courses of daily ASA reduce plasma and nevus PGE2 and some metabolites and cytokines in plasma of human subjects at increased risk for melanoma. PGE2 may be a useful biomarker in blood and nevi for prospective melanoma chemoprevention studies with ASA.

Aspirin & clopidogrel non-responsiveness & its association with genetic polymorphisms in patients with myocardial infarction

Background & objectives:

Cytochrome P450, P2Y12, cyclooxygenase-1 (COX1) and glycoprotein V1 (GPVI) gene polymorphisms are known to affect patient responsiveness towards aspirin and clopidogrel dual antiplatelet therapy (DAPT). The present study was undertaken to identify aspirin and clopidogrel non-responsiveness and its association with genetic polymorphism in patients with myocardial infarction (MI).

Methods:

A total of 207 MI patients who were on DAPT, were included. The DAPT non-responsiveness was determined by light transmittance aggregometry using arachidonic acid and adenosine diphosphate and high platelet reactivity by collagen. Platelet activation biomarkers, thromboxane B₂ (TxB₂) and soluble CD40 ligand (sCD40L) were measured in plasma. Patient compliance was checked by estimating drug and its metabolite levels (aspirin and clopidogrel) in plasma using liquid chromatography-mass spectrometry/mass spectrometry. Genomic DNA was extracted, amplified by polymerase chain reaction and subsequently sequenced to identify CYP450, P2Y12, COX1 and GPVI gene polymorphisms.

Results:

Of the 207 patients, 32 were non-responders. The DAPT non-responsiveness was found in 15.5 per cent patients. The non-responsiveness showed a significant and an independent association with gender [odds ratio (OR)=0.18, 95% confidence interval (CI)=0.01-0.78, P=0.023], TxB₂ (OR=1.00, 95% CI=1.00-1.01, P=0.013), CYP2C19*2 G>A (OR=3.33, 95% CI=1.04-10.69, P=0.044) and GPVI T>C (OR=0.23, 95% CI=0.08-0.67, P=0.007) after adjusting the demographic, clinical and genetic confounding factors when assessed between non-responder and responder compliant patients.

Interpretation & conclusions:

The study showed a significant association of genetic polymorphisms (CYP2C19*2 G>A and GPVI T>C) with DAPT non-responsiveness in MI patients. The findings of this study need further validation in a large cohort of patients with clinical follow up.

The Herb-Drug Interaction of Clopidogrel and Xuesaitong Dispersible Tablet by Modulation of the Pharmacodynamics and Liver Carboxylesterase 1A Metabolism

Objective

Clopidogrel and Xuesaitong dispersible tablet (XST) have been clinically proven to be effective for treating cardiocerebrovascular disease. The present study was to investigate the herb-drug interaction of Clopidogrel and XST by modulation of the pharmacodynamics and liver Carboxylesterase 1A(CES1A) metabolism.

Methods

30 male SD rats were randomly divided into a control group (equal volumes of saline, 6 rats for mRNA analysis), a clopidogrel group (clopidogrel with dose 30 mg/kg), and a combination group (clopidogrel and XST, with dose 30 and 50 mg/kg respectively, each group continuous administration once daily for 30 days). The clopidogrel and combination group comprised 12 rats, with 6 designated for mRNA analysis and 6 for the pharmacokinetic study. The 2-bromo-3'-methoxyacetophenone- (MPB-) derivatized clopidogrel active thiol metabolite (CAMD) was measured by UHPLC-MS/MS for pharmacokinetics (n=6). The expression of CES1A mRNA was examined with real-time RT-PCR (n=6). Molecular simulation was used to investigate the inhibition effect of XST on the CES1A protein. The CAMD pharmacodynamics and CES1A metabolism were investigated to evaluated the herb-drug interaction.

Results

Clopidogrel and XST coadministration appreciably increased the Cmax, AUC, and MRT of CAMD. However, the expression of CES1A mRNA was decreased accordingly. It also indicated that the bioactive components in XST had good interaction with the CES1A metabolism target by molecular simulation. The animal study indicated that clopidogrel and XST coadministration produced significant herb-drug interactions at active CAMD pharmacokinetic and CES1A metabolic enzyme aspect.

Conclusion

30-days dose of coadministration altered hepatic CES1A protein and resulted in reduced plasma levels of active CAMD. both the decreased CES1A mRNA expression and the inhibition on the protein were due to the combination of XST, which accordingly upregulated the pharmacokinetics of plasma active CAMD.

Impaired liver cytochrome P450 2C11 activity after dual antiplatelet therapy with aspirin and clopidogrel in rats

1. Aspirin (ASA) and clopidogrel (CLP) are used in combination as dual antiplatelet therapy (DAPT) for acute coronary syndrome based on their complementary mechanisms for platelet aggregation inhibition. However, the pharmacokinetics of such drug combination usage has not been thoroughly investigated. 2. In the current study, an LC-MS/MS method was developed to simultaneously determine the plasma concentrations of ASA and its metabolite salicylic acid (SA) with CLP and its metabolites, clopidogrel carboxylic acid (CLPM) and clopidogrel active metabolite derivative (CAMD). The pharmacokinetics of ASA, SA, CLP, CLPM and CAMD in rats receiving two-week DAPT with ASA and CLP were then determined. 3. After two-week DAPT with ASA and CLP in rats, the activities of aspirin esterase and rCyp2c11, enzymes mediating rat metabolism of ASA and CLP, respectively, in prepared rat liver microsomes were measured followed by further determination of rCyp2c11 mRNA expressions. The results demonstrated that DAPT led to minimal impact on aspirin esterase activity but significant decrease in rCyp2c11 activity and mRNA expression. 4. In conclusion, our findings on impairment in rCyp2C11 activity and mRNA expression by DAPT in rats could provide guidance on its safe clinical use with other CYP 2C19 substrates.

NSAIDs Determination in Human Serum by GC-MS

Non-steroidal anti-inflammatory drugs (NSAIDs) are being widely consumed without medical prescription and are often the cause of intoxication, usually in young children. For this, there is a special need in their determination in routine toxicology analysis. As screening methods mainly focus on drugs of abuse (DOA) that are alkaline compounds in their majority, they are not optimized for acidic drugs, such as NSAIDs. Thus, more specific methods are needed for the detection and quantification of this class of drugs. In this study, the efficient extraction of NSAIDs from blood serum and their accurate determination is studied. Optimum pH extraction conditions were studied and thereafter different derivatization procedures for their detection. From the derivatization reagents used, N,O-Bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% Trimethylchlorosilane (TMCS) was found to be the optimum choice for the majority of the examined NSAIDs; pH of 3.7 was selected as the most efficient for the extraction step. Herein the formation of the lactam of diclofenac was also thoroughly investigated. The developed Gas Chromatography-Mass Spectrometry (GC-MS) method had a run time of 15 min with the mass spectrometer operating in Electron Impact (EI) within the mass range of 40 to 500 amu. The method was linear with R2 above 0.991 and limits of quantitation (LOQ) ranging from 6 to 414 ng/mL. The intra-day accuracy and precision were found between 1.03%–9.79% and 88%–110%, respectively, and the inter-day accuracy and precision were between 1.87%–10.79% and 91%–113%. The optimum protocol was successfully applied to real clinical samples, where intoxication of NSAIDs was suspected.

A Review of Analytical Methods for the determination of Clopidogrel in Pharmaceuticals and Biological Matrices

P2Y12 belongs to a group of G protein-coupled (GPCR) purinergic receptors and is a receptor for adenosine diphosphate (ADP). The P2Y12 receptor is involved in platelet aggregation and acts as a biological target for treating thromboembolisms and other clotting disorders. The use of Clopidogrel (CLO) has improved the morbidity and mortality endpoints including cardiovascular death, recurrent myocardial infarction (MI) and stroke at 30 days after percutaneous coronary intervention (PCI). CLO is one such drug that specifically and irreversibly inhibits the P2Y12 subtype of ADP receptor. This review delivers a detail description of various analytical methods published for the estimation of CLO and its combinations in pharmaceuticals and biological matrices. The review highlights the basic as well as advanced techniques performed for estimating CLO. The most commonly used assay techniques were UV and Visible spectrophotometry, high performance liquid chromatography (HPLC), high performance thin layer chromatography (HPTLC), micellar liquid chromatography (MLC), micellar electro kinetic chromatography (MEKC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Despite other analytical methods employed for the assay of CLO, the review reveals that the technique of HPLC with UV detection was widely used.

Pharmacokinetic herb-drug interaction of Xuesaitong dispersible tablet and aspirin after oral administration in blood stasis model rats

BACKGROUND

Xuesaitong dispersible tablet (XST) product has been clinically proven to be effective for treating cardio-cerebrovascular disease. Furthermore, herb-drug interactions between the XST product and drugs that are commonly co-administered, such as aspirin (ASA), must be explored to ensure safe clinical use.

STUDY DESIGN AND METHODS

The current study aims to investigate whether the XST product interacts with ASA when they are administered concomitantly to ensure safety and efficacy. A ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of ginsenoside Rg1 (Rg1), ginsenoside Rd (Rd), notoginsenoside R1 (R1) and salicylic acid (SA) in rat plasma to investigate the pharmacokinetic interaction of XST and ASA in blood stasis model rats.

RESULTS AND CONCLUSION

The ASA and XST combination noticeably altered R1 and Rg1 absorption, distribution and disposition. This study indicates that co-administration of XST and ASA can cause an apparent herb-drug pharmacokinetic interaction in blood stasis model rats.