Mechanism analysis of essential oil from Radix Bupleuri for the treatment of asthma through regulation of ectopic olfactory receptor.

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Bupleuri is the root of Bupleurum chinense DC. (BC) and a classic aromatic traditional Chinese medicine. The traditional pharmacological effects of Radix Bupleuri are alleviating bronchial spasms, dilating airways, and promoting the resolution of respiratory inflammation, thereby reducing asthma symptoms. AIM OF THE STUDY: Studies have demonstrated the efficacy of water extracts from BC in asthma treatment. However, the potential role of volatile oil, another active constituent in BC, remains unexplored with asthma. Notably, volatile oil is renowned for its ease of absorption and direct targeting of affected areas, offering distinct advantages in alleviating airway inflammation. This study aims to explain the anti-asthmatic mechanism of BC-oil through in vivo and in vitro pharmacological experiments. MATERIALS AND METHODS: Firstly, the OVA-induced SD rat asthma model was utilized to evaluate the pharmacological effect of BC-oil by lung function monitoring, HE staining, flow cytometry, ELISA, and RT-qPCR. The anti-asthmatic mechanism was further analyzed by combining transcriptomic analysis of lung tissue from rat model and airway smooth muscle tissue from public database. Initially, GC-MS was used to analyze the components of BC-oil. The anti-asthmatic activity was evaluated in 16-HBE, RBL-2H3, and ASMC cells using CAMKII inhibitors to explore of the critical signal transduction regulated by BC-oil. Furthermore, molecular docking and calcium flow assay were utilized to screen and identify the active components from BC-oil. RESULTS: Oral administration of BC-oil significantly enhanced pulmonary function in asthmatic SD rats by reducing airway resistance and elastic resistance. Additionally, BC-oil inhibited inflammatory cytokines, including serum IL-2, pulmonary Il1b, Tnf, and Cxcl13, demonstrating potent anti-inflammatory and immunomodulatory effects. In this study, we analyzed the significant role of OR2W3 in asthma using public transcriptomic data. Furthermore, we indicated that BC-oil regulated the expression of Olr1433 and GNAL in rat lung tissue. BC-oil reduced degranulation and inhibited gene expression of Il3 and Tnf in RBL-2H3 cells and suppressed gene expression of IL8 and TNF in 16-HBE cells. BC-oil also attenuated airway smooth muscle cell proliferation and expression of Acta2 and Ccnd1. Furthermore, BC-oil regulates asthma-related cellular processes by activating CAMKII. GC-MS analysis identified 11 components of BC-oil, and n-hexadecanoic acid, linoleic acid and oleic acid from BC-oil were identified to interact with OR2W3 by molecular docking. The calcium flow assay revealed linoleic acid as a significant activator of OR2W3 and indicated that BC-oil alleviated asthma through the ectopic olfactory signaling pathway. CONCLUSIONS: The mechanism of BC-oil in treating asthma through signal transduction of OR2W3 is revealed at the molecular and cellular levels.

Uncovering the Chemical Composition and Biological Potentials of Bupleurum lancifolium Hornem. from Jordan.

The current study was designed to uncover the chemistry and bioactivity potentials of Bupleurum lancifolium growing wild in Jordan. In this context, the fresh aerial parts obtained from the plant material were subjected to hydrodistillation followed by GC/MS analysis. The main components of the HDEO were γ-patchoulene (23.79%), ß-dihydro agarofuran (23.50%), α-guaiene (14.11%), and valencene (13.28%). Moreover, the crude thanolic extract was partitioned to afford two main major fractions, the aqueous methanol (BLM) and butanol (BLB). Phytochemical investigation of both fractions, using conventional chromatographic techniques followed by careful inspection of the spectral data for the isolated compounds (NMR, IR, and UV-Vis), resulted in the characterization of five known compounds, including α-spinasteryl (M1), ethyl arachidate (M2), ethyl myristate (M3), quercetin-3-O-ß-d-glucopyranosyl-(1-4")-α-L-rhamnopyranosyl (B1), and isorhamnetin-3-O-ß-d-glucopyranosyl-(1-4")-α-L-rhamnopyranosyl (B2). The TPC, TFC, and antioxidant activity testing of both fractions and HDEO revealed an interesting ABTS scavenging potential of the BLB fraction compared to the employed positive controls, which is in total agreement with its high TP and TF contents. Cytotoxic evaluation tests revealed that BLM had interesting cytotoxic effects on the normal breast cell line MDA-MB-231 (ATCC-HTB-26) and the normal dermal fibroblast (ATCC® PCS-201-012) and normal African green monkey kidney Vero (ATCC-CCL-81) cell lines. Despite both the BLB and BLM fractions showing interesting AChE inhibition activities (IC50 = 217.9 ± 5.3 µg/mL and 139.1 ± 5.6 µg/mL, respectively), the HDEO revealed an interestingly high AChE inhibition power (43.8 ± 2.7 µg/mL) that far exceeds the one observed for galanthamine (91.4 ± 5.2 µg/mL). The HDEO, BLM, and BLB exhbitied no interesting antimicrobial activity against Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Escherichia coli, or Pseudomonas aeruginosa.

Comprehensive Analysis Reveals the Difference in Volatile Oil between Bupleurum marginatum var. stenophyllum (Wolff) Shan et Y. Li and the Other Four Medicinal Bupleurum Species.

Volatile oil serves as a traditional antipyretic component of Bupleuri Radix. Bupleurum marginatum var. stenophyllum (Wolff) Shan et Y. Li belongs to the genus Bupleurum and is distinguished for its high level of saikosaponins and volatile oils; nonetheless, prevailing evidence remains inconclusive regarding its viability as an alternative resource of other official species. This study aims to systematically compare the volatile oil components of both dried and fresh roots of B. marginatum var. stenophyllum and the four legally available Bupleurum species across their chemical, molecular, bionics, and anatomical structures. A total of 962 compounds were determined via GC-MS from the dried roots; B. marginatum var. stenophyllum showed the greatest differences from other species in terms of hydrocarbons, esters, and ketones, which was consistent with the results of fresh roots and the e-nose analysis. A large number of DEGs were identified from the key enzyme family of the monoterpene synthesis pathway in B. marginatum var. stenophyllum via transcriptome analysis. The microscopic observation results, using different staining methods, further showed the distinctive high proportion of phloem in B. marginatum var. stenophyllum, the structure which produces volatile oils. Together, these pieces of evidence hold substantial significance in guiding the judicious development and utilization of Bupleurum genus resources.

A comprehensive review of bupleuri radix and its bioactive components： with a major focus on treating chronic liver diseases.

ETHNOPHARMACOLOGICAL RELEVANCE: Bupleuri Radix (BR) has been recognized as an essential herbal medicine for relieving liver depression for thousands of years. Contemporary research has provided compelling evidence of its pharmacological effects, including anti-inflammatory, immunomodulatory, metabolic regulation, and anticancer properties, positioning it as a promising treatment option for various liver diseases. Hepatitis, steatohepatitis, cirrhosis, and liver cancer are among the prevalent and impactful liver diseases worldwide. However, there remains a lack of comprehensive systematic reviews that explore the prescription, bio-active components, and underlying mechanisms of BR in treating liver diseases. AIM OF THE REVIEW: To summarize the BR classical Chinese medical prescription and ingredients in treating liver diseases and their mechanisms to inform reference for further development and research. MATERIALS AND METHODS: Literature in the last three decades of BR and its classical Chinese medical prescription and ingredients were collated and summarized by searching PubMed, Wiley, Springer, Google Scholar, Web of Science, CNKI, etc. RESULTS: BR and its classical prescriptions, such as Xiao Chai Hu decoction, Da Chai Hu decoction, Si Ni San, and Chai Hu Shu Gan San, have been utilized for centuries as effective therapies for liver diseases, including hepatitis, steatohepatitis, cirrhosis, and liver cancer. BR is a rich source of active ingredients, such as saikosaponins, polysaccharides, flavonoids, sterols, organic acids, and so on. These bioactive compounds exhibit a wide range of beneficial effects, including anti-inflammatory, antioxidant, immunomodulatory, and lipid metabolism regulation. However, it is important to acknowledge that BR and its constituents can also possess hepatotoxicity, which is associated with cytochrome P450 (CYP450) enzymes and oxidative stress. Therefore, caution should be exercised when using BR in therapeutic applications to ensure the safe and appropriate utilization of its potential benefits while minimizing any potential risks. CONCLUSIONS: To sum up, BR, its compounds, and its based traditional Chinese medicine are effective in liver diseases through multiple targets, multiple pathways, and multiple effects. Advances in pharmacological and toxicological investigations of BR and its bio-active components in the future will provide further contributions to the discovery of novel therapeutics for liver diseases.

Radix Bupleuri-Radix Paeoniae Alba Inhibits the Development of Hepatocellular Carcinoma through Activation of the PTEN/PD-L1 Axis within the Immune Microenvironment.

OBJECTIVE: This study investigated how Radix Bupleuri-Radix Paeoniae Alba (BP) was active against hepatocellular carcinoma (HCC). METHODS: Traditional Chinese medicine systems pharmacology (TCMSP) database was employed to determine the active ingredients of BP and potential targets against HCC. Molecular docking analysis verified the binding activity of PTEN with BP ingredients. H22 cells were used to establish an HCC model in male balb/c mice. Immunofluorescence staining, immunohistochemistry, flow cytometry, western blotting, enzyme-linked immunosorbent assay, and real-time quantitative PCR were used to study changes in proliferation, apoptosis, PTEN levels, inflammation, and T-cell differentiation in male balb/c mice. RESULTS: The major active ingredients in BP were found to be quercetin, kaempferol, isorhamnetin, stigmasterol, and beta-sitosterol. Molecular docking demonstrated that these five active BP ingredients formed a stable complex with PTEN. BP exhibited an anti-tumor effect in our HCC mouse model. BP was found to increase the CD8+ and IFN-γ+/CD4+ T cell levels while decreasing the PD-1+/CD8+ T and Treg cell levels in HCC mice. BP up-regulated the IL-6, IFN-γ, and TNF-α levels but down-regulated the IL-10 levels in HCC mice. After PTEN knockdown, BP-induced effects were abrogated. CONCLUSION: BP influenced the immune microenvironment through activation of the PTEN/PD-L1 axis, protecting against HCC.

Extraction, purification, structure characteristics, biological activities and pharmaceutical application of Bupleuri Radix Polysaccharide: A review.

Bupleuri Radix (BR), as a well-known plant medicine of relieving exterior syndrome, has a long history of usage in China. Bupleuri Radix Polysaccharide (BRP), as the main component and an important bioactive substance of BR, has a variety of pharmacological activities, including immunoregulation, antioxidant, antitumor, anti-diabetic and anti-aging, etc. In this review, the advancements on extraction, purification, structure characteristics, biological activities and pharmaceutical application of BRP from different sources (Bupleurum chinense DC., Bupleurum scorzonerifolium Willd., Bupleurum falcatum L. and Bupleurum smithii Woiff. var. Parvifolium Shan et Y. Li.) are summarized. Meanwhile, this review makes an in-depth discussion on the shortcomings of the research on BRP, and new valuable insights for the future researches of BRP are proposed.

A comprehensive review on traditional and modern research of the genus Bupleurum (Bupleurum L., Apiaceae) in recent 10 years.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Bupleurum (family Apiaceae), comprising approximately 248 accepted species, is widely distributed and used in China, Japan, India, Central Asia, North Africa and some European countries as traditional herbal medicines. Certain species have been reported to have significant therapeutic effects in fever, inflammatory disorders, cancer, gastric ulcer, virus infection and other diseases. AIM OF THE REVIEW: we performed a comprehensive review of the ten-year research progress in phytochemistry, pharmacology, toxicity, along with bibliometrics research of the genus Bupleurum, aiming to identify knowledge gaps for future research. MATERIALS AND METHODS: All the literatures are retrieved from library and electronic sources including Web of Science, PubMed, Elsevier, Google Scholar, CNKI and Baidu Scholar. These papers cover studies of the traditional use, phytochemistry, pharmacology, and toxicology of the genus Bupleurum. RESULTS: There is a long history of using the genus Bupleurum in traditional herbal medicine that dated back to over 2000 years ago. Twenty-five species and 8 varieties with 3 variants within this genus have been reported to be effective to treat fever, pain, liver disease, inflammation, thoracolumbar pain, irregular menstruation and rectal prolapse. The main phytochemicals found in these plants are triterpene saponins, volatile oil, flavonoid, lignans, and polysaccharides. Many of these compounds have also been shown to have anti-inflammatory, anti-tumor, antimicrobial, immunoregulation, neuroregulation, hepatoprotective and antidiabetic activities. Meanwhile, improper usage of Bupleurum may induce cytotoxic effects, and polyacetylenes may be the main poisonous compounds. CONCLUSIONS: This article summarized recent findings about Bupleurum research from many different aspects. While a small number of Bupleurum species have been investigated through modern pharmacology methods, there are still major knowledge gaps due to inadequate studies and ambiguous findings. Future research could focus on more specific phytochemistry studies combined with mechanistic analysis to provide better guidance to utilize Bupleurum as medicinal resources.

Screening saikosaponin d (SSd)-producing endophytic fungi from Bupleurum scorzonerifolium Willd.

Saikosaponin d (SSd) is an important bioactive compound of traditional Chinese medicinal plant Bupleurum scorzonerifolium Willd. and exhibits many effects, such as anti-tumor, anti-inflammation and immunomodulatory. Since endophytic fungi possess the natural capacity to produce the similar secondary metabolite to that of their host plants, they are promising as alternative sources of plant bioactive natural products. In this study, in order to search for SSd-producing strains, endophytes were isolated from B. scorzonerifolium and were authenticated by the ITS sequence and the translation elongation factor-1alpha gene (TEF-1α) sequence analysis. The profile of metabolites present in the crude exacts was carried out by ultra performance liquid chromatography time-of-flight mass spectrometry (UPLC/Q-TOF-MS) analysis. The results showed that two strains, CHS2 and CHS3 from B. scorzonerifolium could produce SSd by UPLC/Q-TOF-MS analysis, and the amount of SSd produced by strain CHS2 and CHS3 were about 2.17 and 2.40 µg/mL, respectively. CHS2 and CHS3 showed a close phylogenetic relationship to Fusarium oxysporum and Fusarium acuminatum, respectively. According to our concern, no endophytic fungi capable of producing SSd from B. scorzonerifolium have been found before. Our clear intention was to isolate and identify these endophytic fungi that produce important active secondary metabolites, and then study the strains that produce this compound on a large scale through fermentation or even genetic study, to provide a feasible and more convenient way for the production of SSd.

The Polysaccharides from the Aerial Parts of Bupleurum chinense DC Attenuate Epilepsy-Like Behavior through Oxidative Stress Signaling Pathways.

Bupleurum chinense DC. is a traditional Chinese medicine with a long medicinal history and is often used as the main ingredient in prescription drugs for epilepsy. The aerial parts of B. chinense DC. have similar efficacy and composition to B. chinense DC. Therefore, we speculated that the aerial parts of B. chinense DC. could be used in the treatment of epilepsy. Polysaccharides from the aerial parts of B. chinense DC. were selected to explore their therapeutic effects on epilepsy and their potential mechanism of action. The study is aimed at clarifying the antiepileptic effects of the polysaccharides from the aerial parts of B. chinense DC. and their potential underlying mechanisms. The chemical profile of the aerial parts of B. chinense DC. polysaccharides (ABP) was characterized by FT-IR spectrum and HPLC chromatogram. To determine the therapeutic effects of ABPs on epilepsy, we established a kainic acid- (KA-) induced rat model of epilepsy, and through H&E staining, Nissl staining, immunohistochemistry, biochemical analysis, ELISA, and Western blot analysis, we explored the mechanisms underlying the therapeutic effects of ABPs on epilepsy. The monosaccharide content of ABP included galacturonic acid (45.19%), galactose (36.63%), arabinose rhamnose (12.13%), and mannose (6.05%). Moreover, the average molecular weight of ABP was 1.38 × 103 kDa. ABP could improve hippocampal injuries and neuronal function in the KA-induced epilepsy rat model. ABP significantly inhibited oxidative stress in the hippocampus of KA-induced rats. More importantly, ABP could regulate TREM2 activation in the PI3K/Akt/GSK-3ß pathway to inhibit neuronal apoptosis, including increasing the expression of superoxide dismutase and lactate dehydrogenase and decreasing the expression of malondialdehyde. The current study defined the potential role of ABP in inhibiting the development of epilepsy, indicating that ABP could upregulate TREM2 to alleviate neuronal apoptosis, by activating the PI3K/Akt/GSK-3ß pathway and oxidative stress in epilepsy.

Identification and potential mechanism of different components from the aerial part of Bupleurum chinense DC. for epileptic treatment.

The present study aimed to assess the effects of epileptic treatment of the aerial part of Bupleurum chinense DC. in kainic acid (KA)-induced epilepsy rats and LPS-induced BV2 cells, as well as to identify the active chemical constituents. The in vivo and vitro results showed that 20% ethanol elution fractions of the aerial part of B. chinense DC. (BCE-20) and 70% ethanol elution fractions of the aerial part of B. chinense DC. (BCE-70) could improve the epileptic state of the rats and status epilepticus (SE%). Moreover, ultra-high-performance liquid chromatography (UPLC)-Orbitrap- mass spectrometry (MS) analysis identified BCE-20 and 70 as flavonoids and phenylpropanoids, respectively. The mechanistic analysis also showed that BCE-20 and 70 could regulate neurotransmitter abnormalities and suppresses the expression and secretion of pro-inflammatory cytokines. Notably, BCE-20 and 70 could regulate the Triggering receptor expressed on myeloid cells 2 (TREM2)/nuclear factor-k-gene binding (NF-κB)/inhibitor of NF-κB α (IκBα) pathway to inhibit the neuroinflammation. Our findings support the ethnopharmacological use of the constituent polyphenols and flavonoids from the aerial part of B. chinense DC., as the strong anti-epileptic agents.

Bupleurum chinense DC improves CUMS-induced depressive symptoms in rats through upregulation of the cAMP/PKA/CREB signalling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Bupleurum chinense DC. (B. chinense) is the dried root of B. chinense, belonging to the Umbelliferae family. B. chinense has been reported since ancient times for its effect of soothing the liver and relieving depression. Additionally, its important role in treating depression, depressed mood disorders and anti-inflammation has been proven in previous studies. However, its specific mechanism of action remains unknown. AIM OF THE STUDY: The key targets and metabolites of the antidepressant effect of B. chinense were investigated based on the cAMP signalling pathway. The study examined the mechanism for the antidepressant effect of B. chinense by target prediction, analysis of related metabolites and potential metabolic pathways. MATERIALS AND METHODS: A network pharmacology approach was used to predict the antidepressant targets and pathways of B. chinense. A depression rat model was established through the CUMS (chronic unpredictable mild stress) procedure. The depression model was assessed by body weight, sugar-water preference, water maze and enzyme-linked immunosorbent assay (ELISA) indicators (5hydroxytryptamine, etc.). The key metabolic pathways were screened by correlations between metabolites and key targets. Finally, a quantitative analysis of key targets and metabolites was experimentally validated. RESULTS: B. chinense significantly ameliorated the reduction in body weight, sugar-water preference rate and cognitive performance in the water maze experiment in rats with depression induced by CUMS. ELISA, Western blotting (WB) and reverse transcription-polymerase chain reaction (RT-PCR) assays showed that B. chinense significantly improves the expression of protein kinase cyclic adenylic acid (cAMP)-activated catalytic subunit alpha (PRKACA), cAMP-response element-binding protein (CREB) and cAMP activation in the rat brain induced by CUMS. According to metabolic pathway analysis, B. chinense shows an antidepressant effect primarily by regulating the cAMP metabolic pathway. CONCLUSION: B. chinense upregulated PRKACA and CREB expression and the level of the key metabolite cAMP in the cAMP/PKA/CREB pathway while reducing the inflammatory response to depression treatment. These new findings support future research on the antidepressant effects of B. chinense.

A new discovery: Total Bupleurum saponin extracts can inhibit the proliferation and induce apoptosis of colon cancer cells by regulating the PI3K/Akt/mTOR pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Bupleurum chinense DC has a history of using herb in China for more than 2000 years, which can be traced back to the Classic of Shennong Materia Medica in the Han Dynasty. Although Saikosaponin, the main active ingredient of Bupleurum, has the effects of anti-tumor, yet we still do not know the mechanism by total Bupleurum saponin extracts (TBSE) produces this effect on colon cancer. AIM OF THE STUDY: It is predicted by network pharmacology that TBSE may play an anti-colon cancer role by regulating the PI3K-Akt-mTOR pathway. The purpose of this study is to investigate whether TBSE inhibits proliferation and promote apoptosis of colon cancer cells by regulating PI3K/Akt/mTOR pathway. MATERIALS AND METHODS: The effect of saikosaponins on the proliferation of SW480 and SW620 cells was detected by CCK-8, apoptosis was determined by flow cytometry, morphological changes of cells were observed by microscope, nuclear morphological changes were observed after immunofluorescence staining, the expression of apoptosis-related proteins Bax, Bcl2, Caspase3, Caspase9, Cleaved Caspase3 and Cleaved Caspase9 were detected by Western Blot, and the expression of apoptosis-related genes Bax, Bcl2, Caspase3 and Caspase9 were detected by RT-PCR. According to the theory of network pharmacology, the potential targets of saikosaponins and colon cancer were predicted by database Pharmmapper and Genecards database respectively. The intersection of saikosaponins and colon cancer was enriched and analyzed on the Metascape platform. Then, the expression of PI3K/Akt/mTOR pathway related protein PI3K, Akt, Mtor, p-PI3K, p-Akt, p-mTOR were detected by Western Blot, and the corresponding amount of RNA expressions in the pathway was confirmed by RT-PCR. RESULTS: The results of CCK-8 demonstrated that the survival rate of SW480 and SW620 cells decreased significantly when the concentration of TBSE was in the range of 25-200 µg/ml. The morphological observation showed that the cells lost normal cell morphology, cytoplasmic condensation, and partial loss of adhesion after treatment with TBSE. Flow cytometry indicated that the apoptosis rates of SW480 cells and SW620 cells treated with TBSE (50 µg/ml) were 48.47% ± 1.20% and 36.13% ± 1.76%, respectively. Western Blot firstly confirmed that TBSE significantly up-regulated the expression of pro-apoptotic proteins Bax, Caspase3, Caspase9, Cleaved Caspase3 and Cleaved Caspase9, and down-regulated the expression of anti-apoptotic protein Bcl2. And RT-PCR results implied that TBSE significantly up-regulated the gene expression of apoptotic factors Bax, Caspase3 and Caspase9, and significantly decreased the gene expression of Bcl2. It was predicted that the PI3K/Akt/mTOR pathway may be the main regulatory object of the antitumor effect of TBSE by network pharmacology. Subsequent WB experiment also revealed that TBSE could significantly down-regulate (P < 0.01) the expressions of PI3K, Akt, mTOR and phosphorylated proteins P-PI3K, P-Akt, P-MTOR. Meanwhile, RT-PCR results also indicated that TBSE could significantly down-regulate (P < 0.01) the gene expression levels of PI3K, Akt and mTOR. CONCLUSIONS: TBSE activated Bax/Bcl2 and caspase-9/caspase-3 cascade to induced apoptosis of human colon cancer SW480 and SW60 cells in a dose-dependent manner, which was obviously related to the inhibition of PI3K/Akt/mTOR signaling pathway.

Saikosaponin D: review on the antitumour effects, toxicity and pharmacokinetics.

CONTEXT: Bupleuri Radix, the dried root of Bupleurum chinense DC and Bupleurum scorzonerifolium Willd (Apiaceae), is an important medicinal herb widely used to treat cancers for hundreds of years in Asian countries. As the most antitumour component but also the main toxic component in Bupleuri Radix, saikosaponin D (SSD) has attracted extensive attention. However, no summary studies have been reported on the antitumour effects, toxicity and pharmacokinetics of this potential natural anticancer substance. OBJECTIVE: To analyse and summarise the existing findings regarding to the antitumour effects, toxicity and pharmacokinetics of SSD. MATERIALS AND METHODS: We collected relevant information published before April 2021 by conducting a search of literature available in various online databases including PubMed, Science Direct, CNKI, Wanfang database and the Chinese Biological Medicine Database. Bupleurum, Bupleuri Radix, saikosaponin, saikosaponin D, tumour, toxicity, and pharmacokinetics were used as the keywords. RESULTS: The antitumour effects of SSD were multi-targeted and can be realised through various mechanisms, including inhibition of proliferation, invasion, metastasis and angiogenesis, as well as induction of cell apoptosis, autophagy, and differentiation. The toxicological effects of SSD mainly included hepatotoxicity, neurotoxicity, haemolysis and cardiotoxicity. Pharmacokinetic studies demonstrated that SSD had the potential to alter the pharmacokinetics of some drugs for its influence on CYPs and P-gp, and the oral bioavailability and actual pharmacodynamic substances in vivo of SSD are still controversial. CONCLUSIONS: SSD is a potentially effective and relatively safe natural antitumour substance, but more research is needed, especially in vivo antitumour effects and pharmacokinetics of the compound.

Saikosaponins and the deglycosylated metabolites exert liver meridian guiding effect through PXR/CYP3A4 inhibition.

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Bupleuri (RB), traditionally used to treat inflammatory disorders and infectious diseases, represents one of the most successful and widely used herbal drugs in Asia over the past 2000 years. Being realized the role in regulating metabolism and controlling Yin/Yang, RB is not only chosen specifically for treating liver meridian and the corresponding organs, but also believed to have liver meridian guiding property and help potentiate the therapeutic effects of liver. However, the ingredients in RB with liver meridian guiding property and the underly mechanism have not been comprehensively investigated. AIM OF STUDY: Considering the important role of CYP3A4 in first-pass metabolism and the liver exposure of drugs, the present study aimed to determine whether saikosaponins (SSs) and the corresponding saikogenins (SGs) have a role in inhibiting the catalytic activity of CYP3A4 in human liver microsomes and HepG2 hepatoma cells and whether they could suppress CYP3A4 expression by PXR-mediated pathways in HepG2 hepatoma cells. MATERIALS AND METHODS: The effect of SSs and SGs on CYP3A4-mediated midazolam1'-hydroxylation activities in pooled human liver microsomes (HLMs) was first studied. Dose-dependent experiments were performed to obtain the half inhibit concentration (IC50) values. HepG2 cells were used to assay catalytic activity of CYP3A4, reporter function, mRNA levels, and protein expression. The inhibitory effects of SSa and SSd on CYP3A4 activity are negligible, while the corresponding SGs (SGF and SGG) have obvious inhibitory effects on CYP3A4 activity, with IC50 values of 0.45 and 1.30 µM. The similar results were obtained from testing CYP3A4 catalytic activity in HepG2 cells, which correlated well with the suppression of the mRNA and protein levels of CYP3A4. Time-dependent testing of CYP3A4 mRNA and protein levels, as well as co-transfection experiments using the CYP3A4 promoter luciferase plasmid, further confirmed that SSs and SGs could inhibit the expression of CYP3A4 at the transcription level. Furthermore, PXR protein expression decreased in a concentration- and time-dependent manner after cells were exposed to SSs and SGs. PXR overexpression and RNA interference experiments further showed that SSs and SGs down-regulate the catalytic activity and expression of CYP3A4 in HepG2 may be mainly through PXR-dependent manner. CONCLUSION: SSs and SGs inhibit the catalytic activity and expression of CYP3A4 in a PXR-dependent manner, which may be highly related to the liver meridian guiding property of RB.

Polysaccharides of vinegar-baked radix bupleuri promote the hepatic targeting effect of oxymatrine by regulating the protein expression of HNF4α, Mrp2, and OCT1.

ETHNOPHARMACOLOGICAL RELEVANCE: Vinegar-baked Radix Bupleuri (VBRB) is a processed form of Bupleurum chinense DC. As a well-known meridian-guiding drug, it is traditionally used as a component of traditional Chinese medicine formulations indicated for the treatment of liver diseases. However, the liver targeting component in VBRB remains unclear. Therefore, this study aims to explore the efficacy and mechanism of PSS (polysaccharides in Vinegar-baked Radix Bupleuri) in enhancing liver targeting. MATERIALS AND METHODS: Drug distribution of OM alone or combined with PSS was investigated in vivo. Relative uptake efficiency (RUE) and relative targeting efficiency (RTE) were calculated to evaluate liver targeting efficiency. The mRNA and protein expression of organic cation transporter 1 (OCT1), multi-drug resistance protein 2 (Mrp2), and hepatocyte nuclear factor 4α (HNF4α) in the liver were determined by q-PCR and Western blot. Then, AZT, the inhibitor of OCT1 and BI6015, the inhibitor of HNF4α were used to investigate regulatory mechanisms involved in the uptake of OM in the cell. At last, the role of PSS in the anti-hepatitis B virus (HBV) was explored on HepG2.2.15. RESULTS: PSS increased the AUC of OM in the liver and increase the RUE and RTE in the liver which indicated a liver targeting enhancing effect. The mRNA and protein expression of OCT1 was increased while Mrp2 and HNF4α decreased. PSS could increase the uptake of OM in HepG2 by increasing the protein expression of HNF4α and OCT1, while inhibited Mrp2. Moreover, PSS combined with OM could enhance the anti-HBV effect of OM. CONCLUSION: PSS enhanced the liver targeting efficiency and the underlying mechanism related to up-regulating the expression of OCT1 and HNF4α, while down-regulating of Mrp2. These results suggest that PSS may become a potential excipient and provide a new direction for new targeted research.

Effects of saikosaponin-d on CYP3A4 in HepaRG cell and protein-ligand docking study.

Saikosaponin-d (SSd) is a major bioactive triterpenoid saponin extracted from Bupleurum, which has anti-inflammatory, anticancer, antioxidative and anti-hepatic fibrosis effects. Due to the effects of Bupleurum-related formulations on cytochrome P450 (CYPs) expression still remain unclear, the combination therapies involved formulations containing Bupleurum may sometimes lead to unexpected drug-drug interactions in clinical practice. These interactions can limit the clinical applications of related formulations. In this study, we tried to explore the effects of SSd on CYP3A4 mRNA, protein expression and the enzyme activity in HepaRG cells by real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR), Western blot (WB) and HPLC method, respectively. The interaction between SSd and CYP3A4 was analysed by molecular docking. HepaRG cells were cultured with different concentrations of SSd (0.5, 1, 5 and 10 µmol/L) for 72 hours. It is revealed that SSd can inhibit CYP3A4 mRNA and its protein expression, and also the enzyme activity. Molecular docking study demonstrated that SSd can bind to several key active sites of amino acid residues of CYP3A4 protein with hydrogen bonds and hydrophobic interactions. Thus, drug-drug interactions resulted by SSd inhibiting CYP3A4 need attention when formulations containing SSd or Bupleurum are co-administrated with drugs metabolized by CYP3A4.

Effects of Saikosaponin D on CYP1A2 and CYP2D6 in HepaRG Cells.

BACKGROUND: Bupleurum is one of the most important traditional Chinese medicines and an ingredient in many compound preparations. It is widely used together with other drugs in clinical practice, and thus there is great potential for drug-drug interactions. Saikosaponin D (SsD) is a major bioactive triterpenoid saponin extracted from Bupleurum with anti-inflammatory, anticancer, antioxidative, and antihepatic fibrosis effects. Effects of the main components of Bupleurum on cytochromes P450 (CYPs) need to be clarified in the clinical application of combination therapies of formulations containing SsD or Bupleurum. PURPOSE: This study aimed to investigate the effects of SsD on the CYP1A2 and CYP2D6 mRNAs, protein expression, and relative enzyme activities in HepaRG cells. METHODS: HepaRG cells were cultured with SsD at concentrations of 0.5, 1, 5 and 10 µM for 72 hours. mRNA and protein expression of CYP1A2 and CYP2D6 were analyzed with real-time PCR and Western blot analysis. Relative enzyme activities were analyzed with HPLC based on consumption of the specific probe substrate. RESULTS: SsD significantly induced expression of mRNA and increased relative activity of CYP1A2 in HepaRG cells after the cells had been treated with SsD at concentrations of 1, 5 and 10 µM. SsD also induced protein expression of CYP1A2 at concentrations of 5 and 10 µM. SsD exhibited an inductive effect on CYP2D6 mRNA and protein expression, while increasing the relative activity of CYP2D6 at concentrations of 5 and 10 µM. CONCLUSION: This study is the first to investigate the effect of SsD on CYP1A2 and CYP2D6 in HepaRG cells, and the results may provide some useful information on potential drug-drug interactions related to clinical preparations containing SsD or Bupleurum.

New flavonoids from the aerial part of Bupleurum chinense DC.

Four new flavonoids (1-4) and fourteen known compounds (5-18), were isolated from the aerial part of Bupleurum chinense DC. The structural determination of the new flavonoids was accomplished using comprehensive spectroscopic methods, including 1D and 2D NMR spectra with references to the literatures, as well as high-resolution mass spectrometric analysis. The anti-proliferative activities of the flavonoids (1-18) against HeLa cells were evaluated using the MTT assay with cisplatin as the positive control.

A New Alkaloid from the Aerial Parts of Bupleurum chinense DC.

A new isoalloxazine alkaloid, named bupleurine A (1), along with five known compounds (2-6), were isolated from the aerial parts of Bupleurum chinense DC. The structure elucidation of the new alkaloid (1) was employed by combining NMR and HR-MS data with comparison of reference in the literature. Five known compounds (2-6) were isolated from Bupleurum genus for the first time. Additionally, their antiproliferative activities on HeLa cells were evaluated by MTT assay and IC50 of compounds 1 and 4-6 were below 10 µm after treatment for 24 h.

Regulatory effect of a Chinese herbal medicine formula on non-alcoholic fatty liver disease.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) has become a major cause of chronic liver disease. The Chinese herbal medicine (CHM) Dachaihu decoction (DCHD) has been proved to treat NAFLD with good efficacy in previous studies. Based on the TCM principle of formula formation, we divided DCHD into soothing liver part, invigorating spleen part, and dredging intestine part. Marshall officially proposed the concept of "intestinal-hepatic axis", which systematically explains the interactions between the intestine and liver. We hypothesized that the effect of CHM on NAFLD is achieved by regulating the liver and intestine. Thus, we aimed to investigate the possible effect of a CHM formula on NAFLD in a rat model. AIM: To investigate the effects of a CHM formula (a decoction of Chinese thorowax root, scutellaria root, and white peony root) on NAFLD and its regulatory effect on the "intestinal-liver" axis. METHODS: Sixty rats were randomly divided into control, model, pioglitazone hydrochloride (PH), and CHM (a decoction of Chinese thorowax root, scutellaria root, and white peony root) groups. An NAFLD rat model was established using a high-fat high-fructose diet for 16 wk. From the 13th week, rats were administered with PH or a decoction of Chinese thorowax, scutellaria, and white peony root (CHM group) for 4 wk. Rats in the control group and model group were administered with an equal volume of distilled water. At the end of the study, blood was collected via the abdominal aorta. Liver tissues were harvested and any morphological changes were observed by hematoxylin-eosin (HE) staining, Oil red O staining, and Masson staining. In addition, blood lipids, liver function markers, and triglyceride (TG) in liver tissues were analyzed. The levels of transforming growth factor-ß1 (TGF-ß1), tumor necrosis factor-α (TNF-α), Toll-like receptor-4 (TLR4), and nuclear factor-kappa B (NF-кB) in liver tissues and secreted immunoglobulin A (sIgA) in intestinal tissues were analyzed by ELISA, and protein and mRNA expression of occludin and zonula occludens-1 (ZO-1) in the intestine were measured using Western blot and reverse transcription-quantitative polymerase chain reaction, respectively. The endotoxin level in plasma was detected by endpoint chromogenic assay. RESULTS: Compared to the normal control group, the liver coefficient, serum TG, total cholesterol (TC), low density lipoprotein (LDL), aspartate aminotransferase (AST), and alanine aminotransferase (ALT), blood glucose, plasma endotoxin, and the levels of TG, TNF-α, TGF-ß, NF-kB, and TLR4 in liver tissues increased significantly in the model group, while serum high density lipoprotein (HDL), intestinal sIgA, and protein and mRNA expression of occludin and ZO-1 decreased significantly in the model group (P < 0.01). PH and CHM attenuated the elevated liver coefficient, serum TG, TC, LDL, AST, and ALT, blood glucose, plasma endotoxin, and the levels of TG, TNF-α, TGF-ß, NF-kB, and TLR4 in liver tissues and increased serum HDL levels compared to the model group (P < 0.01). Intestinal sIgA and the protein and mRNA expression of intestinal occludin and ZO-1 were significantly increased in the PH group compared to the model and CHM groups (P < 0.01). CONCLUSION: The decoction of Chinese thorowax root, scutellaria root, and white peony root is beneficial in regulating lipid metabolism and liver function, which indicates that it has a good effect on the liver. To a certain extent, this CHM formula can affect both the liver and intestine, while its effect on the liver is superior to that on the intestine.