Identification of metabolites of palmatine in rats after oral administration using ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Recent Applications of Protoberberines as Privileged Starting Materials for the Development of Novel Broad-Spectrum Antiviral Agents: A Concise Review (2017-2023)

Berberine is a well-known phytochemical with significant antiviral activity against a wide range of viruses. Due to having a unique backbone consisting of four interconnected rings, it can be used as a platform for the design and development of novel semisynthetic antiviral agents. The question here is whether novel broad-spectrum antiviral drugs with enhanced activity and toxicity potential can be obtained by attempting to modify the structure of this privileged lead compound. The present study aims to review the results of recent studies in which berberine and its close analogues (protoberberine alkaloids) have been used as starting materials for the production of new semisynthetic antiviral structures. For this purpose, relevant studies published in high-quality journals indexed in databases such as Scopus, Web of Science, PubMed, etc. in the time frame of 2017 to 2023 were collected. Our selection criterion in the current review focuses on the studies in which protoberberines were used as starting materials for the production of semisynthetic agents with antiviral activity during the indicated time period. Correspondingly, studies were identified in which semisynthetic derivatives with significant inhibitory activity against a wide range of viruses including human immunodeficiency virus (HIV), enterovirus 71 (EV71), zika virus (ZIKV), influenza A/B, cytomegalovirus (CMV), respiratory syncytial virus (RSV), and coxsackieviruses were designed and synthesized. Our conclusion is that, despite the introduction of diverse semisynthetic derivatives of berberine with improved activity profiles compared to the parent natural leads, sufficient derivatization has not been done yet and more studies are needed.

UPLC-Q-TOF/MS-Based Serum and Urine Metabonomics Study on the Ameliorative Effects of Palmatine on Helicobacter pylori-Induced Chronic Atrophic Gastritis

Objective

The main objective of this study was to investigate the ameliorative effects of Palmatine (Pal) on Helicobacter pylori (H. pylori) induced chronic atrophic gastritis (CAG)

Method

Body function, serum biochemical indicators and histopathology were used to evaluate the pharmacodynamics of Pal on CAG rats. The target genes expression levels were verified and assessed by RT-PCR and immunohistochemistry (IHC). Moreover, UPLC-Q-TOF/MS analysis based on urine and serum was performed to identify the potential metabolites in the pathological process of CAG induced by H. pylori. Metabolic pathway analysis was performed to elucidate the metabolic network associated with Pal treatment of CAG.

Results

Pal (10, 20, 40 mg/kg/day) significantly restored the body function of CAG rats, reduced the serum biochemical indicators, and maintained the integrity of the gastric mucosal epithelial barrier while alleviated gastric histological damage. Metabolomics analysis shows that the therapeutic effect of Pal on CAG involves 10 metabolites and 10 metabolic pathways, of which the Taurine and hypotaurine metabolism, Glycerophospholipid metabolism and Pentose and glucuronate interconversions are closely related to the gastrointestinal protection of Pal, and these metabolic pathways crosstalk with each other due to the internet hub of citric acid cycle.

Conclusions

Metabolomics was used for the first time to identify potential biomarkers of CAG and to illuminate the therapeutic mechanism of Pal on CAG induced by H. pylori. The results provided a new insight for further research on CAG treatment.

Corydalis Rhizoma as a model for herb-derived trace metabolites exploration: A cross-mapping strategy involving multiple doses and samples

Deciphering the metabolites of multiple components in herbal medicine has far-reaching significance for revealing pharmacodynamic ingredients. However, most chemical components of herbal medicine are secondary metabolites with low content whose in vivo metabolites are close to trace amounts, making it difficult to achieve comprehensive detection and identification. In this paper, an efficient strategy was proposed: herb-derived metabolites were predicted according to the structural characteristics and metabolic reactions of chemical constituents in Corydalis Rhizoma and chemical structure screening tables for metabolites were conducted. The fragmentation patterns were summarized from representative standards combining with specific cleavage behaviors to deduce structures of metabolites. Ion abundance plays an important role in compound identification, and high ion abundance can improve identification accuracy. The types of metabolites in different biological samples were very similar, but their ion abundance might be different. Therefore, for trace metabolites in biological samples, we used the following two methods to process: metabolites of high dose herbal extract were analyzed to characterize those of clinical dose herbal extracts in the same biological samples; cross-mapping of different biological samples was applied to identify trace metabolites based on the fact that a metabolite has different ion abundance in different biological samples. Compared with not using this strategy, 44 more metabolites of clinical dose herbal extract were detected. This study improved the depth, breadth, and accuracy of current methods for herb-derived metabolites characterization.

Capsaicin metabolites and GSH-associated detoxification and biotransformation pathways in human liver microsomes revealed by LC-HRMS/MS with data-mining tools

Capsaicin (CAP) is a principal pungent ingredient in hot peppers, it is also employed as a common food additive, an efficient pharmaceutical component, or even a riot control agent. CAP exerts various pharmacological activities as well as associated adverse physiological responses and causes moderate toxicity if overused. A full screening and identification of CAP metabolites in combination with its main detoxification pathways are crucial for the clear demonstration on its pharmacological and toxicological significance. Here, we employed a post-acquisition data-mining metabolic screening approach to rapidly find and identify a broad range of CAP metabolites generated from in vitro human liver microsomes, based on an ultra-performance liquid chromatography-quadrupole orbitrap high resolution tandem mass spectrometric method. First, we collected full scan MS and MS/MS data sets by a data-dependent acquisition method in positive ion mode, and then we employed a modified mass defect filter and a diagnostic ion filter to screen and identify all the probable CAP metabolites, combining with information including retention time, accurate mass, characteristic fragments, and relevant drug biotransformation patterns. In comparison with the stable isotope-labeled CAP involved biotransformation products, we confirmed 19 functionalized metabolites and 13 glutathione (GSH) conjugates of CAP, in which 13 metabolites are reported for the first time. We then briefly depicted an overview metabolic pathway of CAP from the GSH detoxification viewpoint, revealed that various metabolites of CAP can be generated from single or multiple biotransformation and metabolic reactions. Both CAP and its reactive metabolites produced relevant GSH conjugates, which indicates a wide and important detoxification value of GSH conjugation way.

Palmatine: A review of pharmacological properties and pharmacokinetics

The aim of this review is to collect together the results of the numerous studies over the last two decades on the pharmacological properties of palmatine published in scientific databases like Scopus and PubMed, which are scattered across different publications. Palmatine, an isoquinoline alkaloid from the class of protoberberines, is a yellow compound present in the extracts from different representatives of Berberidaceae, Papaveraceae, Ranunculaceae, and Menispermaceae. It has been extensively used in traditional medicine of Asia in the treatment of jaundice, liver-related diseases, hypertension, inflammation, and dysentery. New findings describe its possible applications in the treatment of civilization diseases like central nervous system-related problems. This review intends to let this alkaloid come out from the shade of a more frequently described alkaloid: berberine. The toxicity, pharmacokinetics, and biological activities of this protoberberine alkaloid will be developed in this work.

Metabolic profile of Rhizoma coptidis in human plasma determined using ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry

RATIONALE

Rhizoma coptidis extract and its alkaloids show various pharmacological activities, but its metabolic profile in human plasma has not been thoroughly investigated. In the present research, the metabolism of Rhizoma coptidis at a clinical dose (5 g/60 kg/day) was systematically analyzed to determine its biotransformation processes in human plasma.

METHODS

In this research, the metabolites of Rhizoma coptidis in human plasma after oral administration of Rhizoma coptidis extract at a clinical dose were investigated using ultra-high-performance liquid chromatography (UHPLC) coupled with high-resolution LTQ-Orbitrap mass spectrometry. The structural elucidation of the constituents was confirmed by comparing their retention times (t_R ) and MSⁿ fragments with those of standards and literature reports.

RESULTS

In total, two prototypes and twelve metabolites were detected in human plasma. The two prototypes were confidently identified using reference standards. Of the compounds detected, M7 (berberrubinen-9-O-glucuronide) was the most abundant based on its peak area, which indicates that this compound might be a pharmacokinetic marker for Rhizoma coptidis alkaloids in humans. Based on the metabolites detected in human plasma, a possible metabolic pathway for Rhizoma coptidis in vivo was proposed.

CONCLUSIONS

The results indicated that the alkaloids in Rhizoma coptidis were extensively biotransformed in vivo mainly via conjugation with glucuronic acid (GluA) or sulfuric acid (SulA) to form phase II metabolites, and the GluA metabolites are likely the dominant form in human plasma. To the best of our knowledge, this is the first in vivo evaluation of the metabolic profile of the whole Rhizoma coptidis extract in human plasma, which is essential for determining the chemicals responsible for the pharmacological activities of Rhizoma coptidis in vivo. Moreover, it would be beneficial for us to further systematically study the pharmacokinetic behavior of Rhizoma coptidis in humans.

Metabolic profiles of corydaline in rats by ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry

1. Corydaline, an isoquinoline alkaloid obtained from the rhizomes of Corydalis yanhusuo, exhibits anti-acetylcholinesterase, anti-angiogenic, anti-allergic and gastric-emptying activities. In this study, a rapid and reliable ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) method was developed and employed for the comprehensive study of the metabolites of corydaline in rats. 2. Altogether, 43 metabolites were identified in the plasma (11), bile (9), urine (34) and feces (21) of rats after oral administration of corydaline at a dose of 4.5mg/kg. 3. It was demonstrated that demethylation, hydroxylation, sulfation and glucuronidation were the major metabolic transformation pathways. Among these, two metabolites were identified as tetrahydropalmatine and isocorybulbine, and 33 phase I and phase II products were inferred to be new metabolites arising from the in vivo metabolism of corydaline. 4. Importantly, this research provides scientific and reliable support for full understanding of the metabolic profiles of corydaline and the results could help to elucidate its safety and efficacy.