Chromatographic fingerprint and quantitative analysis of seven bioactive compounds of Scutellaria barbata

Antioxidative and ROS-dependent apoptotic effects of Cuscuta reflexa Roxb. stem against human lung cancer: network pharmacology and in vitro experimental validation

Lung cancer remains a formidable global health challenge, necessitating the exploration of novel therapeutic approaches. This study investigates the potential of Cuscuta reflexa Roxb. stem extract as an anticancer agent against human lung cancer, focusing on its antioxidative and ROS-dependent apoptotic effects. Utilizing a combination of network pharmacology and in-vitro experimental validation, we delineate the multifaceted molecular mechanisms underlying the observed effects. The antioxidant potential of C. reflexa stem extract was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS•+) and ferric reducing/antioxidant power (FRAP), hydroxyl free radical scavenging, reactive nitrogen oxide scavenging and super oxide anion radical scavenging assays. Furthermore, the antiproliferative and proapoptotic effect of C. reflexa stem extract was evaluated against A549 lung adenocarcinoma cell line using the consecrated sulforhodamine B (SBR) and Annexin V-PI assays. Additionally, the mitochondrial membrane potential (MMP) and the total reactive oxygen species (ROS) estimation assays were performed. As a result, network pharmacology analysis revealed a complex interaction network between the bioactive constituents of C. reflexa and key proteins implicated in lung cancer progression. The C. reflexa stem extract showed dose-dependent antioxidant activity against DPPH• (IC50 - 87.38 µg/mL), reactive nitrogen oxide (IC50 - 318.34 µg/mL), FRAP (IC50 - 359.96 µg/mL), hydroxy free radicals (IC50 - 526.12 µg/mL) than ABTS●+ (IC50 - 698.45 µg/mL) and super oxide anion (IC50 - 892.71 µg/mL) as well as cytotoxic activity against A549 cells (IC50 - 436.80 µg/mL). Observations of morphological features in treated cells have revealed hallmark of apoptosis properties. Furthermore, as a result of treatment with C. reflexa stem extract, ROS generation and mitochondrial depolarization were increased in A549 cells, suggesting that this treatment has significant apoptotic properties. . These findings highlight the potential utility of this natural extract as an innovative therapeutic strategy for lung cancer treatment. The integration of network pharmacology and experimental validation enhances our understanding of the underlying mechanisms and provide the way for further translational research.Communicated by Ramaswamy H. Sarma.

Similarities and differences between Ziqin and Kuqin in anti-inflammatory, analgesic, and antioxidant activities and their core chemical composition based on the zebrafish model and spectrum-effect relationship

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellaria baicalensis (SB) is a traditional Chinese medicine (TCM). In the clinical application of TCM, SB has been divided into two specifications (Ziqin and Kuqin) for a long time. At present, the Chinese Pharmacopoeia Commission no longer distinguishes between the two. However, the two specifications of medicinal materials and pieces are still in circulation in the market.

AIM OF THE STUDY

This work aimed at investigating the similarities and differences between Ziqin and Kuqin in anti-inflammatory, analgesic, and antioxidant activities and their material basis. It will provide a new angle for relevant regulations to formulate the specifications and standards of SB.

MATERIALS AND METHODS

Here we investigated the similarities and differences between Ziqin and Kuqin in anti-inflammatory, analgesic, and antioxidant activities related to four zebrafish models and three chemical tests. The chemical fingerprints of SB (Ziqin and Kuqin) were profiled by HPLC. Meanwhile, UHPLC-Q-TOF/MS was used to identify the chemical constituents of Ziqin and Kuqin. The main effect-related compounds of SB, Ziqin, and Kuqin were screened out by spectrum-effect relationship. Finally, six monomeric compounds were validated experimentally using the zebrafish inflammation model induced by CuSO₄.

RESULTS

Both Ziqin and Kuqin had significant anti-inflammatory, analgesic, and antioxidant activities. Kuqin had better anti-inflammatory and analgesic activities, while Ziqin had better antioxidant activity. HPLC fingerprint and UHPLC-Q-TOF/MS evaluation showed that the chemical composition types and main components of Ziqin and Kuqin were basically the same, while the contents and proportions of chemical components in Ziqin and Kuqin were different. By spectrum-effect relationship, compounds X1, X2 (luteoloside), X3, X4 (baicalin), X6 (wogonoside), X7 (baicalein), X8 (wogonin), and X9 (oroxylin A) were the same active chemical constituents of Ziqin and Kuqin. The core components of anti-inflammatory and analgesia activities in Kuqin were compounds X1, X2, X3, X5, X6, X7, X8, and X9. The antioxidant core active components of Ziqin were compounds X2, X3, X4, X6, X7, and X9. Among them, luteoloside, baicalin, wogonoside, baicalein, wogonin, and oroxylin A were validated successfully with good anti-inflammatory effects.

CONCLUSIONS

This study revealed that Ziqin and kuqin have high similarity in chemical composition, but their proportions and active core components are different. This may be one of the main reasons why they have the same activity but different activity trends. These findings will help to improve the understanding of the different clinical applications of Ziqin and Kuqin, and provide a reference for the formulation of quality standards and their further research.

Integrating chemical profiling and network pharmacology analysis based on anti-inflammatory effects for quality control of Scutellaria barbata

INTRODUCTION

With the wide application of Scutellaria barbata D. Don for hepatitis and mastitis, its quality control issues have also received increasing attention. Based on the multi-component and multi-target characteristics of traditional Chinese medicine, there is an urgent need to establish a quality evaluation system.

OBJECTIVES

This study intends to integrate the "quality-activity-quantification" strategy and establish an activity-related quality control method to ensure the safety and effectiveness of S. barbata.

MATERIAL AND METHODS

Ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry (UPLC/IM-QTOF-MS) was used to characterize the chemical components of S. barbata, and network pharmacological analysis was carried out on the identified components. The index components were determined on the basis of comprehensive activity prediction results and content information. At the same time, the contents of 16 batches of S. barbata from different origins were determined.

RESULTS

A total of 94 compounds were identified according to mass spectrometric data, 12 of which were isolated and structure-confirmed by nuclear magnetic resonance technology. Network pharmacological analysis was applied to predict their key targets and the major pathways mediating their anti-inflammatory effects. On the basis of comprehensive activity prediction and content information, five components were chosen as crucial quality indicators of S. barbata, including scutellarin, scutellarein, luteolin, apigenin, and hispidulin.

CONCLUSION

In this study, 16 different S. barbata batches were compared, and five quality indicators were determined on the basis of qualitative and activity results. The present study provides useful information for evaluating the quality of S. barbata in different areas, and also provides a new basis for the development of quality evaluation methods.

Predicting the herbal medicine triggering innate anti-tumor immunity from a system pharmacology perspective

Although the main focus of immuno-oncology has been manipulating the adaptive immune system, tumor associated macrophages (TAMs) are the main infiltrating component in the tumor microenvironment (TME) and play a critical role in cancer progression. TAMs are mainly divided into two different subtypes: macrophages with antitumor or killing activity are called M1 while tumor-promoting or healing macrophages are named M2. Therefore, controlling the polarization of TAMs is an important strategy for cancer treatment, but there is no particularly effective means to regulate the polarization process. Here, combined systems pharmacology targets and pathways analysis strategy, we uncovered Scutellariae Radix (SR) has the potential to regulate TAMs polarization to inhibit the growth of non-small cell lung cancer (NSCLC). Firstly, systems pharmacology approach was used to reveal the active components of SR targeting macrophages in TME through compound target prediction and target-microenvironment phenotypic association analysis. Secondly, in vitro experiment verified that WBB (wogonin, baicalein and baicalin), major active ingredients of SR are significantly related to macrophages and survival, initiated macrophages programming to M1-like macrophages to promoted the apoptosis of tumor cells. Finally, we evidenced that WBB effectively inhibited tumor growth in LLC (Lewis lung carcinoma) tumor-bearing mice and increased the infiltration of M1-type macrophages in TME. Overall, the systems pharmacology strategy offers a paradigm to understand the mechanism of polypharmacology of natural products targeting TME.

Simple and Rapid Method for Wogonin Preparation and Its Biotransformation

Wogonin is one of the most active flavonoids from Scutellaria baicalensis Georgi (baikal skullcap), widely used in traditional Chinese medicine. It exhibits a broad spectrum of health-promoting and therapeutic activities. Together with baicalein, it is considered to be the one of main active ingredients of Chinese medicines for the management of COVID-19. However, therapeutic use of wogonin may be limited due to low market availability connected with its low content in baikal skullcap and lack of efficient preparative methods for obtaining this compound. Although the amount of wogonin in skullcap root often does not exceed 0.5%, this material is rich in wogonin glucuronide, which may be used as a substrate for wogonin production. In the present study, a rapid, simple, cheap and effective method of wogonin and baicalein preparation, which provides gram quantities of both flavonoids, is proposed. The obtained wogonin was used as a substrate for biotransformation. Thirty-six microorganisms were tested in screening studies. The most efficient were used in enlarged scale transformations to determine metabolism of this xenobiotic. The major phase I metabolism product was 4′-hydroxywogonin—a rare flavonoid which exhibits anticancer activity—whereas phase II metabolism products were glucosides of wogonin. The present studies complement and extend the knowledge on the effect of substitution of A- and B-ring on the regioselective glycosylation of flavonoids catalyzed by microorganisms.

A drug-biomarker interaction model to predict the key targets of Scutellaria barbata D. Don in adverse-risk acute myeloid leukaemia

A poor prognosis, relapse and resistance are burning issues during adverse-risk acute myeloid leukaemia (AML) treatment. As a natural medicine, Scutellaria barbata D. Don (SBD) has shown impressive antitumour activity in various cancers. Thus, SBD may become a potential drug in adverse-risk AML treatment. This study aimed to screen the key targets of SBD in adverse-risk AML using the drug-biomarker interaction model through bioinformatics and network pharmacology methods. First, the adverse-risk AML-related critical biomarkers and targets of SBD active ingredient were obtained from The Cancer Genome Atlas database and several pharmacophore matching databases. Next, the protein-protein interaction network was constructed, and topological analysis and pathway enrichment were used to screen key targets and main pathways of intervention of SBD in adverse-risk AML. Finally, molecular docking was implemented for key target verification. The results suggest that luteolin and quercetin are the main active components of SBD against adverse-risk AML, and affected drug resistance, apoptosis, immune regulation and angiogenesis through the core targets AKT1, MAPK1, IL6, EGFR, SRC, VEGFA and TP53. We hope the proposed drug-biomarker interaction model provides an effective strategy for the research and development of antitumour drugs.

A review of the ethnopharmacology, phytochemistry, pharmacology, and quality control of Scutellaria barbata D. Don

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellaria barbata D. Don (S. barbata) is a well-known perennial herb that is used in traditional Chinese and Korean medicine. In China, it is known as Ban Zhi Lian, while in Korea, it is known as Banjiryun. In the Traditional Chinese Medicine (TCM) system, S. barbata has heat-clearing and detoxifying properties (Qingre Jiedu in Chinese).

AIM OF THE REVIEW

To provide a systematic review on current multifaceted understanding of S. barbata, with particular emphasis on the correlation between its traditional applications and pharmacological activities.

MATERIALS AND METHODS

All available S. barbata-related information from internet databases, including PubMed, Science Direct, Elsevier, China National Knowledge Internet, and Google Scholar (up to October 2018) were searched. Additional information was gathered from classical books on Chinese Herbals, Chinese Pharmacopoeia, and so on.

RESULTS

In the TCM system, S. barbata is mainly prescribed for its heat-clearing and detoxifying effects. More than 203 compounds have been isolated and identified from this herb, with neo-clerodane diterpenoids and flavonoids as the main compounds. Most neo-clerodanes have been demonstrated to have cytotoxic effects against different cancer cell types in vitro. The S. barbata extracts exhibited anti-inflammatory, anti-microbial, antitumor, and other pharmacological activities. To add, flavonoids, including wogonin, baicalein, apigenin, naringenin, and scutellarin, were identified as the key to quality control.

CONCLUSIONS

The heat-clearing effects of S. barbata could be attributed to its anti-inflammatory and hepatoprotective activities, whereas its detoxifying effects might be due to the anti-microbial functions of neo-clerodane diterpenoids and flavones. S. barbata may display anti-tumor effects and through active ingredient analysis, neo-clerodane diterpenoids are suggested to be its representative compounds. Overall, many pre-clinical studies have been conducted but very little concrete evidences are available on its specific effects, which are of therapeutic relevance.

4'-hydroxywogonin inhibits colorectal cancer angiogenesis by disrupting PI3K/AKT signaling

Angiogenesis is fundamental for solid tumor growth and metastasis, and anti-angiogenic therapy has been an important therapeutic option for cancer treatment. Colorectal cancer (CRC) represents the fourth leading cause of cancer-related death worldwide. The current studies were aimed at investigating the anti-angiogenic effects of the natural compound 4'-hydroxywogonin (4'-HW) on CRC-related angiogenesis. Human CRC cell line SW620 cells and normal human intestinal epithelial HIEC cells were cultured and treated with interleukin-6 to mimic the tumor inflammatory microenvironment. Our data showed that 4'-HW reduced the viability of SW620 cells in a concentration- and time-dependent manner. 4'-HW also suppressed the proliferation of SW620 cells, but had little effect on the viability of HIEC cells. Moreover, 4'-HW concentration-dependently decreased the mRNA and protein expression of vascular endothelial growth factor-A (VEGF-A), the predominant pro-angiogenic cytokine in tumor angiogenesis. Subsequently, 4'-HW concentration-dependently inhibited the phosphorylation of phosphatidylinositol 3-kinase (PI3K) and AKT. PI3K inhibitor wortmannin, similar to 4'-HW, significantly downregulated the VEGF-A expression in SW620 cells, and combination of wortmannin and 4'-HW produced more significant effects. Finally, human umbilical vein endothelial cells (HUVECs) incubated with the conditioned medium of 4'-HW-treated SW620 cells exhibited impaired angiogenic capacity at Matrigel. Incubation with the neutralizing antibody against VEGF-Aalone also suppressed the angiogenic properties of HUVECs in vitro. Collectively, 4'-HW decreased the viability and reduced angiogenesis in CRC, which was associated with downregulation of VEGF-A expression by disrupting the PI3K/AKT pathway. Our discoveries suggested 4'-HW as a promising anticancer agent against CRC targeting angiogenesis.

Using the Chinese herb Scutellaria barbata against extensively drug-resistant Acinetobacter baumannii infections: in vitro and in vivo studies

Background

No animal model studies have been conducted in which the efficacy of herbal compounds has been tested against multidrug-resistant Acinetobacter baumannii infections. Very few antibiotics are available for the treatment of pulmonary infections caused by extensively drug-resistant Acinetobacter baumannii (XDRAB). To find alternative treatments, traditional Chinese herbs were screened for their antimicrobial potential.

Methods

The present study screened 30 herbs that are traditionally used in Taiwan and that are commonly prescribed for heat clearing and detoxification. The herbs with antibacterial activities were analysed by disc diffusion assays, time-kill assays and a murine lung infection model.

Results

Of the 30 herbs tested, only Scutellaria barbata demonstrated 100% in vitro activity against XDRAB. Furthermore, we compared the antibacterial effect of the S. barbata extract with that of colistin, and the S. barbata extract showed better antibacterial effect. In the XDRAB pneumonia murine model, we compared the antimicrobial effects of the orally administered S. barbata extract (200 mg/kg, every 24 h), the intratracheally administered colistin (75,000 U/kg, every 12 h), and the control group. The bacterial load in the lungs of the treatment group that received the oral S. barbata extract showed a significant decrease in comparison to that in the lungs of the control group. In addition, histopathological examinations also revealed better resolution of perivascular, peribronchial, and alveolar inflammation in the oral S. barbata extract-treated group.

Conclusions

Our in vitro and in vivo data from the animal model support the use of S. barbata as an alternate drug to treat XDRAB pulmonary infections. However, detailed animal studies and clinical trials are necessary to establish the clinical utility of S. barbata in treating XDRAB pulmonary infections.

4'-Hydroxywogonin suppresses lipopolysaccharide-induced inflammatory responses in RAW 264.7 macrophages and acute lung injury mice

4'-Hydroxywogonin (4'-HW), a flavonoid, has been isolated from various plants and shown to inhibit NO production in macrophages. However, the molecular mechanisms and its in vivo activity have not been determined. Our study aimed to investigate the mechanisms underlying the anti-inflammatory effects of 4'-HW in vitro and in vivo. We showed that 4'-HW potently reduced the expression levels of COX-2 and iNOS as well as their products, prostaglandin E2 (PGE2) and nitric oxide (NO) respectively, in LPS-stimulated RAW 264.7 macrophages. 4'-HW also suppressed LPS-induced pro-inflammatory cytokines at mRNA and protein levels. Moreover, 4'-HW blocked the interaction of TAK1 and TAB1 in LPS-stimulated RAW 264.7 macrophages, resulting in an inhibition of the TAK1/IKK/NF-κB signaling pathway. Furthermore, 4'-HW also reduced the phosphorylation of MAPKs and PI3/Akt signaling pathways in LPS-stimulated RAW 264.7 macrophages. 4'-HW was also significantly decreased the intracellular reactive oxygen species (ROS) level. The effect of 4'-HW was confirmed in vivo. 4'-HW exhibited potent protective effect against LPS-induced ALI in mice. These findings indicate that 4'-HW suppresses the LPS-induced response in vitro and in vivo. It is likely that the inhibition of the TAK1/IKK/NF-κB, MAPKs and PI3/AKT signaling pathways contribute to the anti-inflammatory effects of 4'-HW. Our study suggests that 4'-HW may be an important functional constituent in the plants and has the potential value to be developed as a novel anti-inflammatory agent.

Pitaya Extracts Induce Growth Inhibition and Proapoptotic Effects on Human Cell Lines of Breast Cancer via Downregulation of Estrogen Receptor Gene Expression

Breast cancer is one of the most prevalent cancers in the world and is also the leading cause of cancer death in women. The use of bioactive compounds of functional foods contributes to reduce the risk of chronic diseases, such as cancer and vascular disorders. In this study, we evaluated the antioxidant potential and the influence of pitaya extract (PE) on cell viability, colony formation, cell cycle, apoptosis, and expression of BRCA₁, BRCA₂, PRAB, and Erα in breast cancer cell lines (MCF-7 and MDA-MB-435). PE showed high antioxidant activity and high values of anthocyanins (74.65 ± 2.18). We observed a selective decrease in cell proliferation caused by PE in MCF-7 (ER⁺) cell line. Cell cycle analysis revealed that PE induced an increase in G₀/G₁ phase followed by a decrease in G₂/M phase. Also, PE induced apoptosis in MCF-7 (ER⁺) cell line and suppressed BRCA₁, BRCA₂, PRAB, and Erα gene expression. Finally, we also demonstrate that no effect was observed with MDA-MB-435 cells (ER⁻) after PE treatment. Taken together, the present study suggests that pitaya may have a protective effect against breast cancer.

Established Human Cell Lines as Models to Study Anti-leukemic Effects of Flavonoids

Despite the extensive work on pathological mechanisms and some recent advances in the treatment of different hematological malignancies, leukemia continues to present a significant challenge being frequently considered as incurable disease. Therefore, the development of novel therapeutic agents with high efficacy and low toxicity is urgently needed to improve the overall survival rate of patients. In this comprehensive review article, the current knowledge about the anticancer activities of flavonoids as plant secondary polyphenolic metabolites in the most commonly used human established leukemia cell lines (HL-60, NB4, KG1a, U937, THP-1, K562, Jurkat, CCRF- CEM, MOLT-3, and MOLT-4) is compiled, revealing clear anti-proliferative, pro-apoptotic, cell cycle arresting, and differentiation inducing effects for certain compounds. Considering the low toxicity of these substances in normal blood cells, the presented data show a great potential of flavonoids to be developed into novel anti-leukemia agents applicable also in the malignant cells resistant to the current conventional chemotherapeutic drugs.

Determination of scutellarin in breviscapine preparations using quantitative proton nuclear magnetic resonance spectroscopy

The objective of the present study was to develop the selection criteria of proton signals for the determination of scutellarin using quantitative nuclear magnetic resonance (qNMR), which is the main bioactive compound in breviscapine preparations for the treatment of cerebrovascular disease. The methyl singlet signal of 3-(trimethylsilyl)propionic-2,2,3,3-d₄ acid sodium salt was selected as the internal standard for quantification. The molar concentration of scutellarin was determined by employing different proton signals. To obtain optimum proton signals for the quantification, different combinations of proton signals were investigated according to two selection criteria: the recovery rate of qNMR method and quantitative results compared with those obtained with ultra-performance liquid chromatography. As a result, the chemical shift of H-2′ and H-6′ at δ 7.88 was demonstrated as the most suitable signal with excellent linearity range, precision, and recovery for determining scutellarin in breviscapine preparations from different manufacturers, batch numbers, and dosage forms. Hierarchical cluster analysis was employed to evaluate the determination results. The results demonstrated that the selection criteria of proton signals established in this work were reliable for the qNMR study of scutellarin in breviscapine preparations.

Preparative isolation of six anti-tumour biflavonoids from Selaginella doederleinii Hieron by high-speed counter-current chromatography

INTRODUCTION

Biflavonoids are the primary constituents of Selaginella doederleinii Hieron, to which different bioactivities have been attributed, including anti-cancer, anti-inflammatory, anti-oxidant, anti-fungal and anti-virus activity. However, effective methods for separation of these compounds are not currently available.

OBJECTIVE

To develop a high performance and bioassay-guided method for preparative isolation of biflavonoids from S. doederleini via high-speed counter-current chromatography (HSCCC).

METHODS

The anti-proliferation effects of four fractions (70% ethanol, petroleum ether, dichloromethane and acetic ether extracts) of S. doederleinii on five human cancer cells were monitored. The dichloromethane and acetic ether extracts showed good cytotoxicities to the studied cancer cell lines, guiding the subsequent separation. Two solvent systems composed of n-hexane:ethyl acetate:methanol:water (1:2:1.5:1.5, v/v) and n-hexane:ethyl acetate:methanol:water (3:2:3:2, v/v) were developed for separation of the active fractions, respectively. Identification of the biflavonoids was performed by EI-MS(n) , (1) H- and (13) C-NMR.'

RESULTS

Under the optimised conditions, 12.6 mg amentoflavone (91.4%), 6.6 mg robustaflavone (90.4%), 7.5 mg 2'', 3''-dihydro-3', 3'''-biapigenin (98.2%) and 7.3 mg 3', 3'''-binaringenin (90.3%) from acetic ether extract (500 mg) and 6.3 mg heveaflavone (93.5%) and 5.3 mg 7, 4', 7'', 4'''-tetra-O-methyl-amentoflavone (94.5%) from dichloromethane extract (200 mg) were obtained, respectively. The anti-proliferation effects of the six biflavonoids on the five human cancer cells were further verified.

CONCLUSION

The study provides methodological references for simultaneously preparative isolation of several bioactive biflavones from the herbal family of Selaginella. It is the first report discovering 2'', 3''-dihydro-3', 3'''-biapigenin and 3', 3'''-binaringenin from this herb and describing their cytotoxicities to human cancer cell lines.

Scutellaria barbata D. Don extract synergizes the antitumor effects of low dose 5-fluorouracil through induction of apoptosis and metabolism

Traditional Chinese medicines have been recognized as a new source of anticancer drugs or chemotherapy adjuvant to enhance the efficacy of chemotherapy and to ameliorate the side effects. This study aimed to investigate the antitumor effects of combined Scutellaria barbata D. Don extract (SBE) and 5-FU treatment in vitro and in vivo and the potential mechanisms. SBE was prepared and analyzed by HPLC. Tumor growth inhibition both in vitro and in vivo, cell apoptosis, apoptosis related protein expressions (P53, bid, bax, bcl-2), caspase-3 activities and 5-FU related enzymes were assessed. SBE could significantly synergize the antitumor effects of low dose 5-FU both in vivo and in vitro. SBE could increase the apoptosis inducing effect of low dose 5-FU in both Bel-7402 and HCT-8 cells. Also, caspase-3 activities, P53 and bax expressions were significantly increased, while bid and bcl-2 expressions were significantly decreased in drug combination groups, compared with individual drug treatment groups. Furthermore, SBE could significantly decrease the mRNA levels of dihydropyrimidine dehydrogenase. These results showed that combined treatment with SBE and low dose 5-FU can significantly inhibit the tumor growth both in vitro and in vivo, which might be related with apoptosis and regulations of 5-FU metabolism.

Ethnopharmacological and bioactivity guided investigation of five TCM anticancer herbs

ETHNOPHARMACOLOGICAL RELEVANCE

Five herbs, Curcuma longa L. (CL), Scutellaria baicalensis Georgi (SBC), Scutellaria barbata D. Don (SBB), Hedyotis diffusa Willd. (HD) and Solanum nigrum L. (SN), are often prescribed in the polyherbal formulas for cancer treatment by traditional Chinese medicine (TCM) practitioners. The purpose of the present study was to identify important anticancer herbs used in TCM and carry out bioactivity-directed fractionation and isolation (BDFI) using six cancer cell lines as well as peripheral blood mononuclear cells (PBMCs), to identify constituents with anticancer activity but devoid of toxic effects against healthy immune cells.

MATERIALS AND METHODS

Of 243 document anticancer TCM treatments, 199 anticancer TCM herbs were ranked by the number of literature reports for each herb. Five herbs were identified from the top 50 ranked herbs by at least two out of three TCM practitioners as frequently used in the TCM treatment of cancer. BDFI using MTS assay was applied to determine the active anticancer extracts, fractions, and finally discrete compounds.

RESULTS

Five herbs were selected for study of their anticancer activities. The extracts of Curcuma longa L., Scutellaria barbata D. Don, and Hedyotis diffusa showed antiproliferative activity to various extents, extracts of Scutellaria baicalensis Georgi and Solanum nigrum L. showed little anticancer activity. Seven out of the 21 fractions obtained from Hedyotis diffusa Willd. showed anticancer activity. One new compound, ethyl 13(2) (S)-hydroxy-chlorophyllide a(1), along with 10 known compounds, i.e. 2-methyl-3-methoxyanthraquinone (2), 2-hydroxymethylanthraquinone(3), 2-hydroxy-3-methylanthraquinone(4), 2-hydroxymethy-1-hydroxyanthraquinone(5), 1-methoxy-2-hydroxyanthraquinone(6), 2-hydroxy-3-methyl-1-methoxyanthraquinone (7), oleanolic acid (8), ursolic acid (9), stigmasterol (10) and docosanoic acid (11), were isolated and identified. Compounds 2-6, 8 and 9 dose-dependently inhibited the cell viability of cancer cells within a concentration range of 1-200µM. Furthermore, compounds 2, 3, 5 and 9 showed significantly stronger inhibition of tested cancer cell lines than on that of PBMCs.

CONCLUSION

This study identified anticancer herbs, extracts, fractions and eventually compounds from the documented anticancer TCM herbs by using BDFI. It also determined the antiproliferative activity in cancer and healthy immune cells of the isolated compounds from Hedyotis diffusa. The results will be useful in the validation of the clinical application of these herbs and the development of novel anticancer therapeutics.

Multidimensional information-based HPLC technologies to evaluate traditional chinese medicine

Traditional Chinese medicines (TCMs) are usually complex mixtures and contain hundreds of chemically different constituents, which make the quality control (QC) of crude drugs and their medical preparations extremely difficult. In the past years, with the rapid development of modern instrumental analysis and computer-aided data processing techniques, great progress has been made in the research of quality standards and the development of QC techniques. Among them, the use of the high-performance liquid chromatography (HPLC) technique is one of the best approaches because of its high separation efficiency. However, one-way separation, single detection methods or data processing cannot meet the needs of the QC of TCMs. Multidimensional information-based HPLC technologies such as two-dimensional HPLC, HPLC coupled with several different detection methods and HPLC fingerprint combined with multicomponent quantification have solved this problem with their comprehensive analysis; these methods have gradually been accepted by more researchers for further in-depth study. The present work provides an overview of the development of QC for TCMs based on HPLC technologies with modern hyphenated techniques, multiseparation methods and some common data processing methods in fingerprint spectra over the last six years.