Metabolite identification of iridin in rats by using UHPLC-MS/MS and pharmacokinetic study of its metabolite irigenin

Herbal textual research of Belamcanda chinensis (L.) redouté and screening of quality-markers based on 'pharmacodynamics-substance'

ETHNOPHARMACOLOGICAL RELEVANCE

Belamcanda chinensis (L.) Redouté is widely distributed in East Asia, such as China, Russia and North Korea. Belamcandae Rhizoma is the sun-dried rhizome of B. chinensis and has a long history of traditional medicinal use. It was first recorded in the Shennong's Herbal Classic, and has the effects of clearing heat and detoxifying, eliminating phlegm and benefiting the pharynx.

AIM OF THE STUDY

To systematically study the source of Belamcandae Rhizoma, summarize the evolution of its medicinal properties, efficacy and the application history of its prescriptions, summarize its biological activity, phytochemistry, synthetic metabolic pathway and toxicology, and screen the Quality-Markers of Belamcandae Rhizoma according to the screening principle of traditional Chinese medicine Quality-Markers.

MATERIALS AND METHODS

All information available on Belamcandae Rhizoma was collected using electronic search engines, such as Pubmed, Web of Science, CNKI, WFO (www.worldfloraonline.org), MPNS (https://mpsn.kew.org), Changchun University of Traditional Chinese Medicine Library collections, Chinese Medical Classics.

RESULTS

The source of Belamcandae Rhizoma is B. chinensis of Iridaceae. It has a long history of application in China. It has the effects of clearing heat and detoxifying, eliminating phlegm and promoting pharynx. Modern pharmacological studies have shown that it has anti-inflammatory, anti-oxidation, anti-tumor and other physiological activities, and is safe and non-toxic at normal application doses. At present, tectoridin, iridin, tectorigenin, irigenin and irisflorentin are identified as the Quality-Markers of Belamcandae Rhizoma.

CONCLUSIONS

As a traditional Chinese medicine, Belamcandae Rhizoma has a long history of application, and multifaceted studies have demonstrated that Belamcandae Rhizoma is a promising Chinese medicine with good application prospects. By reviewing and identifying the Quality-Markers of Belamcandae Rhizoma, this study can help to establish the evaluation procedure of it on the one hand, and identify the shortcomings research on the other hand. Currently, there are few studies on the anabolism and toxicology of it, and future studies may focus on its in vivo processes, toxicology and adverse effects.

Pharmacokinetics and metabolite identification of 23-hydroxybetulinic acid in rats by using liquid chromatography-mass spectrometry method

23-hydroxybetulinic acid (23-HA), a main bioactive component isolated from Pulsatilla chinensis (Bunge) Regel, exhibits various pharmacological activities, such as antimelanoma, antileukemia, anti-colon cancer, and antihepatotoxicity. Although the main active ingredient anemoside B4 (AB4) from this plant has been well studied, research on its active metabolite 23-HA is limited. In the present study, a validated HPLC-QQQ-MS/MS method was established for the quantification of 23-HA in rat plasma. Pharmacokinetics analysis showed that the absorption and elimination of 23-HA in rats were rapid, with an oral bioavailability as 12.9 %. After oral administration with 50 mg/kg 23-HA for SD rats, the plasma, urine, feces, and bile samples were collected and analyzed by UPLC-Q Exactive Plus MS and HPLC-QQQ-MS/MS. Seventeen metabolites of 23-HA were identified, and its major metabolic pathways included oxidation, hydration, sulfation, and glucuronidation. This study highlights the first detailed investigation of 23-HA's pharmacokinetics in rats along with its metabolism in vivo, and will provide robust evidence for further research and clinical application of 23-HA.

Study on quality difference between Belamcanda chinensis (L.) DC and Iris tectorum Maxim. based on chemical chromatogram analysis, biological activity evaluation and in vivo distribution rule

ETHNOPHARMACOLOGICAL RELEVANCE

Belamcanda chinensis (L.) DC. (BC) and Iris tectorum Maxim. (ITM) have been widely used in recent years due to their remarkable curative effects on sore throat, cough and asthma. but they are often misused due to their similar appearance. A comprehensive comparison of the chemical composition, biological activity, pharmacokinetics and tissue distribution between the two active differential components has not been performed. Differences in their specific effects have not been fully elucidated.

AIM OF THE STUDY

This work aims at differentiating between BC and ITM in terms of appearance, chemical composition, biological activity, pharmacokinetics and tissue distribution.

MATERIALS AND METHODS

In this study, the HPLC-FP method was used to find the differences between the chemical components of BC and ITM. The pharmacological experiments were used to compare the differences in activity, including in vitro anti-inflammatory activity with LPS-induced inflammation model of RAW 264.7 cells, inhibition of AChE activity, and the regulation of isolated small intestinal smooth muscle in mice. The pharmacokinetic and tissue distribution profiles were used to analyze the differences between the two in rats.

RESULTS

The types of isoflavones in BC and ITM are basically the same, but their contents in ITM is much higher than that in BC. At the same doses, the release of TNF-α, NO, IL-1β and IL-6 from RAW 264.7 cells in the ITM group was lower than that of the BC group, and the in vitro anti-inflammatory activity of ITM was stronger than that of BC. Meanwhile, ITM had stronger inhibition ability to inhibit AChE activity than BC. The BC extract exhibited an inhibitory effect on the isolated small intestinal smooth muscle of mice, and the ITM extract showed stimulatory effect at low concentration and inhibitory effect at high concentration. There were significant differences in drug-time profiles, kinetic parameters and tissue distribution.

CONCLUSIONS

There are significant differences in the multidimensional aspects of appearance, chemical composition, biological activity, pharmacokinetics, and tissue distribution between BC and ITM. This study provides a theoretical basis for the quality control, pharmacological efficacy and clinical application of the two herbs.

Pro-apoptotic effect of chloroform fraction of Moraea sisyrinchium bulb against glioblastoma cells

INTRODUCTION

Glioblastoma is a common malignant brain tumor, with limited therapeutic options. In our previous study, the Moraea sisyrinchium plant showed cytotoxicity against glioblastoma and hepatocellular carcinoma cells. Among different parts of this plant (flower, stem, and bulb), the bulb showed better anticancer potential. The present work aimed to test the anticancer activity of different fractions of the bulb extract, to determine its phytochemicals, and to study its mechanism action on glioblastoma.

METHODS

The bulb extract was partitioned into different fractions using immiscible solvents. The U87 glioblastoma cells were incubated with the obtained fractions. Then, the cell proliferation assay (MTT), cell migration test (scratch), cell cycle analysis (propidium iodide staining), apoptosis/necrosis assay (annexin V/propidium iodide staining), and real-time PCR (PTEN, Akt, mTOR, BAX and BCL-2 genes) were performed. Phytochemicals were determined using liquid chromatography-mass spectroscopy.

RESULTS

The chloroform fraction showed more antiproliferative effect than n-hexane, ethyl acetate, and n-butanol fractions. Also, chloroform fraction induced cell cycle arrest, increased apoptosis, and inhibited cell migration ability (P < 0.05). The expression of PTEN, mTOR, and BAX genes was significantly up-regulated, while the expression of Akt and Bcl-2 showed down-regulation. The phytochemicals identified in the chloroform fraction were mainly xanthones, phytosterols, and isoflavones.

CONCLUSION

The chloroform fraction of Moraea sisyrinchium bulb inhibits the proliferation and migration of glioblastoma cells by inducing cell cycle arrest and apoptosis by upregulation of the PTEN gene and Bax/Bcl-2 ratio. The identified compounds in the chloroform fraction are potential candidates for further investigation as anticancer agents against glioblastoma.

Potential herb‒drug interactions between anti-COVID-19 drugs and traditional Chinese medicine

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. Effective treatments against COVID-19 remain urgently in need although vaccination significantly reduces the incidence, hospitalization, and mortality. At present, antiviral drugs including Nirmatrelvir/Ritonavir (Paxlovid^TM), Remdesivir, and Molnupiravir have been authorized to treat COVID-19 and become more globally available. On the other hand, traditional Chinese medicine (TCM) has been used for the treatment of epidemic diseases for a long history. Currently, various TCM formulae against COVID-19 such as Qingfei Paidu decoction, Xuanfei Baidu granule, Huashi Baidu granule, Jinhua Qinggan granule, Lianhua Qingwen capsule, and Xuebijing injection have been widely used in clinical practice in China, which may cause potential herb-drug interactions (HDIs) in patients under treatment with antiviral drugs and affect the efficacy and safety of medicines. However, information on potential HDIs between the above anti-COVID-19 drugs and TCM formulae is lacking, and thus this work seeks to summarize and highlight potential HDIs between antiviral drugs and TCM formulae against COVID-19, and especially pharmacokinetic HDIs mediated by metabolizing enzymes and/or transporters. These well-characterized HDIs could provide useful information on clinical concomitant medicine use to maximize clinical outcomes and minimize adverse and toxic effects.

Pharmacokinetic and metabolite profile of orally administered anemoside B4 in rats with an improved exposure in formulations of rectal suppository

ETHNOPHARMACOLOGICAL RELEVANCE

Pulsatilla chinensis (Bunge) Regel is a traditional Chinese herbal medicine used to treat intestinal amebiasis, malaria, vaginal trichomoniasis, and bacterial infections. Anemoside B4 (AB4), a pentacyclic triterpenoid saponin, is one of the primary bioactive substances in Pulsatilla chinensis (Bunge) Regel, and gavage administration of AB4 to animals has been demonstrated to exhibit anticancer, anti-inflammatory, and antiviral actions. However, AB4 exposure in plasma is very low after oral administration, and the biotransformation of AB4 in vivo after oral administration remains unknown.

AIM OF THE STUDY

The reason for conducting this research was to explore at the metabolite profile of AB4 in rats following oral administration. Additionally, we aimed to develop an appropriate extravascular formulation to increase the exposure and duration of AB4 in vivo.

MATERIALS AND METHODS

A well-validated HPLC-QQQ-MS/MS method was used for the quantification of AB4 in plasma and was further applied to evaluate and compare the pharmacokinetic properties of AB4 dissolved in a saline solution and AB4 formulations in a rectal suppository or enteric capsule. Reliable UHPLC coupled to Q-Exactive Plus high-resolution MS was used to identify the metabolites in rat plasma, bile, urine, and faeces.

RESULTS

AB4 was extensively metabolized, and a total of 29 metabolites were identified. The primary metabolic routes included deglycosylation, oxidation, dehydrogenation, reduction, sulfation, hydration, acetylation, and glucuronidation. The pharmacokinetic comparison showed that both the rectal suppository and enteric capsule increased the exposures of AB4 and one of its active metabolites, 23-hydroxybetulinic acid (23-HA). Notably, rectal suppositories increased systemic AB4 exposure (AUC_0-∞) by approximately 49 and 28 times higher than that of the AB4 saline solution and enteric capsules, respectively. The t_1/2 of AB4 was extended to approximately 11 h after rectal administration compared to 2 h after oral administration.

CONCLUSION

Overall, our study demonstrated that the mismatched exposure-response relationship of AB4 could result from extensive metabolism in the gastrointestinal and circulatory systems. Thus, a rectal suppository could be an alternative formulation of AB4 to obtain both higher and longer exposure.

UGT1A1 and UGT1A9 Are Responsible for Phase II Metabolism of Tectorigenin and Irigenin In Vitro

Tectorigenin and irigenin are biologically active isoflavones of Belamcanda chinensis (L.) DC. Previous studies indicated that both compounds could be metabolized in vivo; however, the kinetic parameters of enzymes involved in the metabolization of tectorigenin and irigenin have not been identified. The aim of this study was to investigate UGTs involved in the glucuronidation of tectorigenin and irigenin and determine enzyme kinetic parameters using pooled human liver microsomes (HLMs) and recombinant UGTs. Glucuronides of tectorigenin and irigenin were identified using high-performance liquid chromatography (HPLC) coupled with mass spectrometry and quantified by HPLC using a response factor method. The results showed that tectorigenin and irigenin were modified by glucuronidation in HLMs. One metabolite of tectorigenin (M) and two metabolites of irigenin (M1 and M2) were detected. Chemical inhibition and recombinant enzyme experiments revealed that several enzymes could catalyze tectorigenin and irigenin glucuronidation. Among them, UGT1A1 and UGT1A9 were the primary enzymes for both tectorigenin and irigenin; however, the former mostly produced irigenin glucuronide M1, while the latter mostly produced irigenin glucuronide M2. These findings suggest that UGT1A1 and UGT1A9 were the primary isoforms metabolizing tectorigenin and irigenin in HLMs, which could be involved in drug–drug interactions and, therefore, should be monitored in clinical practice.