BACKGROUND: 3-acetyl-11-keto-beta-boswellic acid (AKBA) and 11-keto-boswellic acid (KBA) are the main active components of frankincense as pentacyclic triterpenoids, which are designated by the European Pharmacopoeia 8.0 as the quality standard for the evaluation of Indian frankincense, 2-methoxy-8,12-epoxygermacra-1(10),7,11-trien-6-one (MCS134) is a non-volatile sesquiterpene compound in myrrh. OBJECTIVE: In this paper, the absorption pharmacokinetics and metabolites of AKBA, KBA and MCS134 after frankincense, myrrh and their compatibility were analyzed, elaborated their absorption and metabolism mechanism and provided the ideas for the research on the bioactive components of frankincense and myrrh compatibility in vivo. METHODS: The area under the blood concentration time curve (AUC), half-life (t1/2) and drug clearance (CL) of AKBA, KBA and MCS134 in rats were analyzed by LC-TQ / MS. The metabolites of AKBA, KBA and MCS134 in rats were analyzed by ultra-high pressure liquid chromatography with a linear ion trap-high resolution Orbitrap mass spectrometry system (UHPLC-LTQ-Orbitrap-MS). RESULTS: The results showed that AKBA, KBA and MCS134 reached the maximum plasma concentration at about 2 h, 2 h and 15 min, respectively. AUC0-t and t1/2 of the three components increased in varying degrees after compatibility, and the clearance/ bioavailability (CL/F) decreased. AKBA, KBA and MCS134 were metabolized in phase I and phase II in rats, and there represented differences before and after compatibility. CONCLUSION: After the compatibility of frankincense and myrrh, the absorption of effective components was improved to some extent, and there were some differences in the metabolites in rats. The results provide ideas for elucidating the in vivo effect mechanism of frankincense and myrrh.

BACKGROUND: Nifurtimox is an effective treatment for patients with Chagas disease, but knowledge of its biotransformation and excretion is limited. OBJECTIVE: This study aimed to better understand the role of oral nifurtimox in vivo. METHODS: We investigated the exposure and excretion pathways of [14C]-labeled nifurtimox and its metabolites in rats. We then quantified the prominent metabolites and nifurtimox in the urine and plasma of patients receiving nifurtimox using LC-HRMS with reference standards and quantified these compounds in rat plasma after a single, high dose of nifurtimox. We also investigated potential drug-drug interactions (DDIs) of these compounds in vitro. RESULTS: In rats, orally administered nifurtimox was rapidly absorbed (tmax 0.5 h) and eliminated (t½ 1.4 h). Metabolism of nifurtimox yielded six predominant metabolites (M-1 to M-6) in urine and plasma, and the dose was excreted equally via the renal and fecal routes with only traces of unchanged nifurtimox detectable due to its instability in excreta. In patients with Chagas disease, only M-6 and M-4 achieved relevant exposure levels, and the total amount of excreted metabolites in urine was higher in fed versus fasted patients, consistent with the higher systemic exposure. For nifurtimox, M-6, and M-4, no potential perpetrator pharmacokinetic DDIs with the main cytochrome P-450 enzymes and drug transporters were identified in vitro. CONCLUSION: This contemporary analysis of the complex metabolite profile and associated exposures emerging after oral dosing of nifurtimox in rats and humans, together with the expected low risk for clinically relevant DDIs, expands the understanding of this important anti-trypanosomal drug.

BACKGROUND: Chemotherapeutic drugs used in cancer treatment often result in gastrointestinal toxicity, notably diarrhea, impacting patients' quality of life. Complementary and Alternative Medicine (CAM) has garnered increasing interest as an alternative to conventional approaches as a potential solution for managing chemotherapy-induced diarrhea (CID). OBJECTIVE: To summarize current research focusing on herbal medicines as adjuvant therapy to prevent or treat chemotherapy-induced diarrhea, including clinical assessments, mechanism of actions, active components, and potential pharmacokinetic interactions between herbal medicines and chemotherapeutic drugs. METHODS: We performed the literature review from PubMed, CNKI, Google Scholar, Web of Science, and Scopus using "Chemotherapy", "Diarrhea," and "Complementary and Alternative Medicine" as the search keywords. RESULTS: Using herbal medicines as adjuvants provides an effective approach to treating or preventing CID with improved or unaffected antitumor activity of chemotherapeutic drugs. Among these herbal formulations, scutellaria, ginger, and ginseng are the most frequently used herbs in the prescriptions for CID. The main antidiarrheal components in herbs are wogonin, baicalin, chrysin, quercetin, gingerol, and ginsenosides. These herbs, formulations, and bioactive components relieved CID through different mechanisms, including directly decreasing local drug exposure, anti-inflammation, inhibiting epithelial apoptosis, or promoting epithelium stem cell regeneration. The application of herbal medicines as adjunctive therapies showed efficacy in preventing or treating CID in multiple clinical trials. However, more well-designed clinical studies are expected to validate the results further. Despite some clinical studies demonstrating that certain herbal medicines could potentially attenuate CID and improve efficacy, it remains necessary to evaluate herbal safety. The interactions between herbs and drugs are also potential concerns, but few clinical trials have focused on investigating this aspect. CONCLUSION: In clinical practise, herbal medications show potential as adjuvant treatments for gastrointestinal toxicities brought on by chemotherapy, particularly diarrhoea. Further well-designed clinical studies are needed to validate their efficacy, ensure safety, and explore potential drug-herb interactions.

BACKGROUND: Chebulinic acid (CA) is an active constituent of Terminalia chebula fruits with therapeutic potential against multiple metabolic diseases, including dementia, benign prostate hyperplasia, and osteoporosis. OBJECTIVE: The present work intends to explore the preclinical pharmacokinetics, including the absolute bioavailability of CA and its influence on the gene expression of cytochrome P450 enzymes in the liver. METHODS: Quantifying CA and probe drugs in vitro samples and preclinical serum samples of male SD rats were performed using LC-MS/MS. The influence of CA on the hepatic CYPs and their gene expression was analyzed in rat liver by quantitative real-time polymerase chain reaction. RESULTS: The plasma protein binding was found to be 84.81 ± 7.70 and 96.34 ± 3.12, blood-to-plasma ratio of 0.62 ± 0.16 and 0.80 ± 0.23 at 1 µM and 10 µM concentrations, respectively. Again, the absolute oral bioavailability of CA at 100 mg/kg was found to be 37.56 ± 7.3%. The in-vivo pharmacokinetic profile of probe drugs revealed CA to have significant inducing effects on CYP1A2, 2C11, 2D2, and 2E1 after 14 days, which correlates to both in-vitro rat microsomal data and gene expression results. CONCLUSION: Altogether, pharmacokinetic parameters reveal CA to have an affinity to distribute across different extravascular tissues and induce rat liver CYP enzymes.

BACKGROUND: Palbociclib and ribociclib are substrates of efflux transporter, P-glycoprotein plays a key role in absorption and transport of these drugs. Proton pump inhibitors, when co-administered with them are known to show inhibitory effect on P-glycoprotein. OBJECTIVE: Therefore, this study aims to investigate the role of proton pump inhibitors in inhibition of P-glycoprotein mediated efflux of palbociclib and ribociclib. METHOD: A combined approach of molecular docking and ex vivo everted gut sac model was implemented to predict the potential of proton pump inhibitors i.e., omeprazole, esomeprazole, lansoprazole, pantoprazole and rabeprazole to inhibit the P-glycoprotein mediated intestinal transport of palbociclib and ribociclib and study the molecular basis of interaction taking place. RESULTS: Molecular docking studies revealed that omeprazole, rabeprazole and pantoprazole bound to the ATP site of nucleotide binding domain with binding energies of -27.53, -29.56 and -38.44 Kcal/mol respectively. In ex-vivo studies, rabeprazole and omeprazole, affected the absorptive permeability of palbociclib by 3.04 and 1.26 and ribociclib by 1.76 and 2.54 folds, respectively. Results of molecular docking studies and ex vivo studies highlighted that proton pump inhibitors bound to the ATP binding site to block its hydrolysis thereby inhibiting the P-glycoprotein mediated efflux of palbociclib and ribociclib. CONCLUSION: The experimental evidence presented highlights the fact that proton pump inhibitors have potential to inhibit P-glycoprotein, giving rise to drug interactions with palbociclib and ribociclib. Hence, monitoring is required while proton pump inhibitors and cyclin-dependent kinase inhibitors are being co-administered to avoid adverse events.