Constituents of the aerial parts of Eclipta prostrata and their cytotoxicity on human ovarian cancer cells in vitro

Ethanol extract of Eclipta prostrata induces multiple myeloma ferroptosis via Keap1/Nrf2/HO-1 axis

BACKGROUND

Multiple myeloma (MM) is an incurable hematological malignancy with limited therapeutic efficacy. Eclipta prostrata is a traditional Chinese medicinal plant reported to possess antitumor properties. However, the effects of E. prostrata in MM have not been explored.

PURPOSE

The aim of this study was to define the mechanism of the ethanol extract of E. prostrata (EEEP) in treating MM and identify its major components.

METHODS

The pro-ferroptotic effects of EEEP on cell death, cell proliferation, iron accumulation, lipid peroxidation, and mitochondrial morphology were determined in RPMI-8226 and U266 cells. The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), kelch-like ECH-associated protein 1 (Keap1), heme oxygenase-1 (HO-1), glutathione peroxidase 4 (GPX4), and 4-hydroxynonenal (4HNE) were detected using western blotting during EEEP-mediated ferroptosis regulation. The RPMI-8226 and U266 xenograft mouse models were used to explore the in vivo anticancer effects of EEEP. Finally, high performance liquid chromatography (HPLC) and ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry system (UPLC-Q/TOF-MS) were used to identify the major constituents of EEEP.

RESULTS

EEEP inhibited MM cell growth and induced cell death in vitro and in vivo. By promoting malondialdehyde and Fe2+ accumulation, lipid peroxidation, and GSH suppression, EEEP triggers ferroptosis in MM. Mechanistically, EEEP regulates the Keap1/Nrf2/HO-1 axis and stimulates ferroptosis. EEEP-induced lipid peroxidation and malondialdehyde accumulation were blocked by the Nrf2 activator NK-252. In addition, HPLC and UPLC-Q/TOF-MS analysis elucidated the main components of EEEP, including demethylwedelolactone, wedelolactone, chlorogenic acid and apigenin, which may play important roles in the anti-tumor function of EEEP.

CONCLUSION

In summary, EEEP exerts its anti-MM function by inducing MM cell death and inhibiting tumor growth in mice. We also showed that EEEP can induce lipid peroxidation and accumulation of ferrous irons in MM cells both in vivo and in vitro, leading to ferroptosis. In addition, this anti-tumor function may be achieved by the EEEP activation of Keap1/Nrf2/HO-1 axis. This is the first study to reveal that EEEP exerts anti-MM activity through the Keap1/Nrf2/HO-1-dependent ferroptosis regulatory axis, making it a promising candidate for MM treatment.

Unlocking Therapeutic Potential: Comprehensive Extraction, Profiling, and Pharmacological Evaluation of Bioactive Compounds from Eclipta alba (L.) Hassk. for Dermatological Applications

Herbal medicine has been studied as an alternate approach to modern medicine as it is more cost-effective and accessible via natural sources. Eclipta alba (E. alba, L.) Hassk. is a weed plant abundantly distributed throughout different regions of the world and contains abundant bioactive compounds used for various skin conditions. In this review, we aimed to gather information from the literature about the extraction, separation, and identification of these bioactive compounds and their potential in skin diseases. Relevant studies published before August 2023 were identified and selected from electronic databases, including Scopus, SciFinder, ScienceDirect, Google Scholar, and Wiley Library, using the following keywords: Eclipta alba, Eclipta prostrata, phytochemicals, extraction, separation, isolation, identification, characterization, pharmacological activity, and skin conditions. Up-to-date extraction, separation, and identification methods of bioactive compounds from E. alba and their skin-related pharmacological activities are discussed in this review. As there are limitations regarding extraction, separation, and identification methods, and in-depth mechanistic and human studies of the skin-related pharmacological activities of bioactive compounds, these gaps are areas for future research to expand our understanding and broaden the potential applications of this medicinal weed plant, including the development of cosmeceutical and skincare products, anti-inflammatory agents, and formulations for dermatological treatments.

Antioxidant and Antiproliferative Activities of Eclipta prostrata (L.) L. Extract and Isolated Compounds

The primary objective of this study was to elucidate the chemical composition, antioxidant properties, and antiproliferative activities of Eclipta prostrata extracts. Two flavonoids, 3'-O-methylorobol and apigenin 7-sulfate, were isolated from the ethyl acetate (EtOAc) extract of E. prostrata. The total phenolic and flavonoid contents of the E. prostrata extracts, as well as their overall antioxidant activities as measured using the 2,2-diphenyl-1-picrylhydrazyl and reducing power assays, were investigated. The E. prostrata EtOAc extract exhibited significantly greater antioxidant activities in both assays and higher phenol and flavonoid contents than the other extracts. The potential antiproliferative properties of the E. prostrata extracts and isolated compounds were investigated in vitro against the AGS, A549, and HT-29 cancer cell lines and the normal human HEK-293 cell line using the MTT assay. Annexin V-FITC/PI staining analysis and quantitative real-time PCR were used to assess AGS cell apoptosis. At a concentration of 100 µg/mL, the EtOAc extract of E. prostrata reduced AGS cell viability and proliferation by inducing apoptosis through the alteration of gene expression in the apoptotic cascade. These results highlight E. prostrata as a promising source of anticancer compounds.

Echinocystic acid induces the apoptosis, and inhibits the migration and invasion of non-small cell lung cancer cells

An increasing amount of evidence has demonstrated the anticancer activity of triterpenes extracted from traditional medicines. Echinocystic acid (EA), a natural triterpene isolated from Eclipta prostrata (L.) L., has previously been shown to exhibit anticancer activity in HepG2 and HL-60 cells. The aim of the present study was to investigate the anticancer activity of EA in non-small cell lung cancer (NSCLC) cells. For this purpose, the viability and proliferation of A549 cells were determined using a Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine staining. The migratory and invasive ability of the A549 cells were measured using wound healing and Transwell assays. Hoechst staining was also performed to detect the apoptosis of A549 cells. The proliferation of A549 cells and the distributions of different growth phases were determined using a flow cytometer. Western blot analysis was used to detect the expression levels of cyclin D, partitioning defective 3 homolog (Par3), PI3K, Akt, mTOR, Bax, Bcl-2 and caspase-3. EA inhibited the proliferation, and the migratory and invasive abilities of cultured lung carcinoma cells (A549 cells), and induced cell cycle arrest in the G₁ phase of the cell cycle. Treatment with EA upregulated Par3 expression and inhibited the PI3K/Akt/mTOR pathway in vitro. In addition, EA treatment inhibited tumor growth, suppressed proliferation and induced the apoptosis of tumor cells in NSCLC tumor xenografts in mice. On the whole, these results suggest that EA may represent a potential therapeutic agent for NSCLC.

Thiophene-containing compounds with antimicrobial activity

Thiophene, as a member of the group of five-membered heterocycles containing one heteroatom, is one of the simplest heterocyclic systems. Many synthetic strategies allow the accurate positioning of various functionalities onto the thiophene ring. This review provides a comprehensive, systematic and detailed account of the developments in the field of antimicrobial compounds featuring at least one thiophene ring in their structure, over the last decade.

Thiophenes-Naturally Occurring Plant Metabolites: Biological Activities and In Silico Evaluation of Their Potential as Cathepsin D Inhibitors

Naturally, thiophenes represent a small family of natural metabolites featured by one to five thiophene rings. Numerous plant species belonging to the family Asteraceae commonly produce thiophenes. These metabolites possessed remarkable bioactivities, including antimicrobial, antiviral, anti-inflammatory, larvicidal, antioxidant, insecticidal, cytotoxic, and nematicidal properties. The current review provides an update over the past seven years for the reported natural thiophene derivatives, including their sources, biosynthesis, spectral data, and bioactivities since the last review published in 2015. Additionally, with the help of the SuperPred webserver, an AI (artificial intelligence) tool, the potential drug target for the compounds was predicted. In silico studies were conducted for Cathepsin D with thiophene derivatives, including ADMET (drug absorption/distribution/metabolism/excretion/and toxicity) properties prediction, molecular docking for the binding interaction, and molecular dynamics to evaluate the ligand-target interaction stability under simulated physiological conditions.

Eclipta prostrata (L.) L. (Asteraceae): Ethnomedicinal Uses, Chemical Constituents, and Biological Activities

Eclipta prostrata (L.) L. (Syn.: Eclipta alba (L.) Hassak, Family: Asteraceae) is an important medicinal plant in the tropical and subtropical regions. It is widely used in treating various diseases of skin, liver and stomach in India, Nepal, Bangladesh, and other countries. The main aim of this review was to collect and analyze the available information on traditional uses, phytoconstituents, and biological activities of E. prostrata. The scientific information was collected from the online bibliographic databases such as Scopus, MEDLINE/PubMed, Google Scholar, SciFinder, etc. and books and proceedings. The active phytochemicals were coumestan derivatives, phenolic acid derivatives, flavonoids, triterpenoid and steroid saponins, substituted thiophenes, etc. Various extracts and isolated compounds of E. prostrata showed a wide range of biological activities such as antimicrobial, anticancer, hepatoprotective, neuroprotective and hair growth promoting activities. Relatively a few studies have been performed to reveal the exact phytoconstituents responsible for their corresponding pharmacological activities. Future studies should focus on detailed mechanism based studies using animal models and clinical studies.

Thiophene enantiomers from the aerial parts of Eclipta prostrata

Ten thiophene derivatives (1-10), including two previously undescribed ones (1 and 2), have been obtained and structurally characterized from the aerial parts of a traditional Chinese herb Eclipta prostrata. Six of them with one chiral center were identified to be scalemic mixtures, and the pure enantiomers of two isolates (1 and 3) were successfully separated via chemical derivatization and chiral HPLC, with the absolute configurations being established by analysis of optical rotations. All the thiophenes were subjected to a series of assays and compounds 9 and 10 exhibited mild antibacterial activity against Staphylococcus aureus.[Formula: see text].

Thiophene-Based Trimers and Their Bioapplications: An Overview

Certainly, the success of polythiophenes is due in the first place to their outstanding electronic properties and superior processability. Nevertheless, there are additional reasons that contribute to arouse the scientific interest around these materials. Among these, the large variety of chemical modifications that is possible to perform on the thiophene ring is a precious aspect. In particular, a turning point was marked by the diffusion of synthetic strategies for the preparation of terthiophenes: the vast richness of approaches today available for the easy customization of these structures allows the finetuning of their chemical, physical, and optical properties. Therefore, terthiophene derivatives have become an extremely versatile class of compounds both for direct application or for the preparation of electronic functional polymers. Moreover, their biocompatibility and ease of functionalization make them appealing for biology and medical research, as it testifies to the blossoming of studies in these fields in which they are involved. It is thus with the willingness to guide the reader through all the possibilities offered by these structures that this review elucidates the synthetic methods and describes the full chemical variety of terthiophenes and their derivatives. In the final part, an in-depth presentation of their numerous bioapplications intends to provide a complete picture of the state of the art.

Bioactive terpenoid constituents from Eclipta prostrata

Chemical fractionation of the ethanolic extract of Eclipta prostrata yielded a series of unreported terpenoid constituents, including a rare 6/6/6/6-fused tetracyclic triterpenoid, a pentacyclic triterpenoid, two pentacyclic triterpenoid saponins, a diterpenoid and a sesquiterpenoid. Structures were assigned to these compounds on the basis of comprehensive spectroscopic analyses, with the absolute configurations of the tetracyclic triterpenoid, the diterpenoid and the sesquiterpenoid being determined via explanation of electronic circular dichroism data. Screening of these isolates in an array of bioassays revealed antibacterial, cytotoxic and α-glucosidase inhibitory activities for selective compounds. Of particular interest, the tetracyclic triterpenoid showed very strong inhibition against α-glucosidase with an IC₅₀ of 0.82 ± 0.18 μM, being 10³-fold as active as the positive control acarbose.

Triterpenoids

This review covers newly isolated triterpenoids that have been reported during 2015.

A review on traditional uses, phytochemistry and pharmacology of Eclipta prostrata (L.) L

ETHNOPHARMACOLOGICAL RELEVANCE

Eclipta prostrata, a traditional herbal medicine, has long been used in Asia and South America for the therapy of hemorrhagic diseases (e.g. hemoptysis, hematemesis, hematuria, epistaxis and uterine bleeding), skin diseases, respiratory disorders, coronary heart disease, hair loss, vitiligo, snake bite and those caused by the deficiency of liver and kidney.

AIM OF THE REVIEW

In this review, we highlight relatively comprehensive and up-to-date information of E. prostrata on traditional uses, phytochemistry, pharmacology and toxicity, along with featuring the gaps in current knowledge, aiming to provide references for future research and possible opportunities for well applications of this medicinal plant.

MATERIALS AND METHODS

Information on E. prostrata was gathered from scientific databases (Google Scholar, Web of Science, Scifinder, Baidu Scholar, PubMed and CNKI). Information was also obtained from local books, Ph.D. theses and M.Sc. dissertations and Chinese Pharmacopoeia. The plant taxonomy was validated by the database "The Plant List".

RESULTS

Various phytochemical classes has been identified and isolated from the plant covering triterpenes, flavonoids, thiopenes, coumestans, steroids and others. Among these, coumestans are reported as the most common ingredients. The isolated crude extracts and individual compounds have been reported to exhibit promising pharmacological properties, such as hepatoprotective, osteoprotective, cytotoxic, hypoglycaemic, anti-inflammatory, anti-microbial, hypolipidemic, promoting hair growth, rejuvenative and neuroprotective effects.

CONCLUSIONS

Until now, significant progress has been witnessed in phytochemistry and pharmacology of E. prostrata. Thus, some traditional uses has been well supported and clarified by modern pharmacological studies. Moreover, E. prostrata also showed therapeutic potential in some refractory diseases such as cancer, dementia and diabetes. But, present findings are still insufficient that cannot satisfactorily explain some mechanisms of action. More well-designed studies in vitro especially in vivo are required to establish links between the traditional uses and bioactivities, discover new skeletons and activity molecules, as well as ensure safety before clinical use.

Bio-modified TiO2 nanoparticles with Withania somnifera, Eclipta prostrata and Glycyrrhiza glabra for anticancer and antibacterial applications

Titanium dioxide nanoparticles exhibit good anticancer and antibacterial activities. They are known to be environmentally friendly and stable, less toxic and excellent biocompatibility nature. In this paper we report the biological properties of pure TiO₂ nanoparticles modified with Withania somnifera (Ashwagandha), Eclipta prostrata (Karisalankanni) and Glycyrrhiza glabra (Athimathuram) for biological applications. X-ray diffraction results revealed the anatase nature of the samples. From the TEM analyses, it is observed that there is an increase in the particle size of the bio modified samples. UV results show the red shift for the bio modified samples when compared with the pure samples. The samples are then subjected to MTT assay to determine the cell viability. KB oral cancer cells are used for the determination of anticancer nature of the pure and bio modified nanoparticles. It is observed that Withania somnifera - Eclipta prostrate modified TiO₂ nanoparticles exhibit excellent anticancer activities among other bio modified and pure samples. The samples are then examined for their antibacterial activities against three Gram-negative bacterial strains namely, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and two Gram-positive bacterial strains namely, Staphylococcus aureus and Streptococcus mutans. Among the modified and pure samples, Withania somnifera - Eclipta prostrata showed good antibacterial nature against Gram-positive and Gram-negative bacteria.

Antimetastatic effects of Eclipta prostrata extract on oral cancer cells

Eclipta prostrata, a traditional Chinese medication, has been used for the treatment of several diseases. However, the molecular mechanism underlying the effects of Eclipta prostrata extracts (EPE) on human oral cancer cell metastasis remains unclear. We thus examined the effects of EPE on metastasis promoting proteins in oral cancer. Our results revealed that the EPE attenuated SCC-9, HSC-3, and TW2.6 cell migration and invasiveness by reducing matrix metalloproteinase (MMP)-2 enzyme activities. In addition, Western blot analysis revealed that EPE significantly reduced the levels of phosphorylated extracellular signal-regulated kinase 1/2 (ERK 1/2) but not those of c-Jun N-terminal kinase (JNK) 1/2 and p38. In conclusion, we found that EPE could inhibit oral cancer metastasis through the inhibition of MMP-2 expression. Therefore, EPE may be used to prevent the metastasis of oral cancer, and has the potential to be applied to cancer treatment.

Ethnopharmacological uses, phytochemistry, biological activities, and biotechnological applications of Eclipta prostrata

Eclipta prostrata belongs to a family of medicinal plants (Asteraceae) and plays a role in the treatment of several diseases, including infectious hepatitis, snake venom poisoning, gastritis, and respiratory diseases such as a cough and asthma. A number of compounds, including thiophene derivatives, steroids, triterpenes, flavonoids, polyacetylenes, polypeptides, and coumestans, have been isolated from E. prostrata. The plant functional compounds can act as reducing agent in the field of nanoparticle synthesis. The extracts of E. prostrata are widely used for green biosynthesis of various metal and metal oxide nanoparticles, nanoparticles, which showed a potential for pharmaceutical, biotechnological, and biomedical applications. Establishment of a efficient in vitro regeneration and genetic transformation method of E. prostrata is a vital prerequisite for application of biotechnology in order to improve secondary metabolite yields. The present mini-review discusses its pharmacological profile, chemical constituents, biotechnological, and ethnomedical uses, mainly focusing on antimyotoxic, antihemorrhagic, antiproliferative, antioxidant, antitumor, antihyperglycemic, antidementia, antimicrobial, antihyperlipidemic, antivenom, anti-HIV, and larvicidal activities, so that the pharmaceutical potential of the plant can be better evaluated. The mini review, providing up-to-date phytochemical and other information on E. prostrata, will serve a reference for further studies.

Inhibition of Cytochrome P450 (CYP3A4) Activity by Extracts from 57 Plants Used in Traditional Chinese Medicine (TCM)

Background:

Herbal medicine is widely used all over the world for treating various health disorders. It is employed either alone or in combination with synthetic drugs or plants to be more effective.

Objective:

The assessment of the effect of both water and methanol extracts of 57 widely used plants from Traditional Chinese Medicine (TCM) against the main phase I metabolizing enzyme CYP3A4 in vitro for the first time.

Materials and Methods:

The inhibition of cytochrome P450 activity was evaluated using a luminescence assay. The principal component analysis (PCA) was used to correlate the inhibitory activity with the main secondary metabolites present in the plant extracts. Molecular modeling studies on CYP3A4 (PDB ID 4NY4) were carried out with 38 major compounds present in the most active plant extracts to validate the observed inhibitory effect.

Results:

Aqueous extracts of Acacia catechu, Andrographis paniculata, Arctium lappa, Areca catechu, Bupleurum marginatum, Chrysanthemum indicum, Dysosma versipellis, and Spatholobus suberectus inhibited CYP3A4 is more than 85% (at a dose of 100 μg/mL). The corresponding methanol extracts of A. catechu, A. paniculata, A. catechu, Mahonia bealei, and Sanguisorba officinalis inhibited the enzyme by more than 50%. Molecular modeling studies revealed that two polyphenols, namely hesperidin and rutin, revealed the highest fitting scores in the active sites of the CYP3A4 with binding energies equal to -74.09 and -71.34 kcal/mol, respectively.

Conclusion:

These results provide evidence that many TCM plants can inhibit CYP3A4, which might cause a potential interference with the metabolism of other concomitantly administered herbs or drugs.

SUMMARY

In this study, the inhibitory activity of the aqueous and methanol extracts of 57 widely used plants from Traditional Chinese Medicine (TCM) against the main phase I metabolizing enzyme CYP3A4 was tested in vitro for the first time.

Aqueous extracts of Acacia catechu, Andrographis paniculata, Arctium lappa, Areca catechu, Bupleurum marginatum, Dysosma versipellis, and Spatholobus suberectus inhibited CYP3A4 by more than 85% (at a dose of 100 μg/mL).

The activity could be attributed to the presence of polyphenolics as revealed from the multivariate chemometric analysis and molecular modeling study.

These results provide evidence that many TCM plants can inhibit CYP3A4, which might cause a potential interference with the metabolism of other concomitantly administered herbs or drugs.

Abbreviation used: CHARMm: Chemistry at HARvard Macromolecular Mechanics, CYP: Cytochrome P450, DMSO: Dimethyl Sulfoxide, PCA: Principal Component Analysis, PDB: Protein Data Bank, TCM: Traditional Chinese Medicine

Alcoholic Extract of Eclipta alba Shows In Vitro Antioxidant and Anticancer Activity without Exhibiting Toxicological Effects

As per WHO estimates, 80% of people around the world use medicinal plants for the cure and prevention of various diseases including cancer owing to their easy availability and cost effectiveness. Eclipta alba has long been used in Ayurveda to treat liver diseases, eye ailments, and hair related disorders. The promising medicinal value of E. alba prompted us to study the antioxidant, nontoxic, and anticancer potential of its alcoholic extract. In the current study, we evaluated the in vitro cytotoxic and antioxidant effect of the alcoholic extract of Eclipta alba (AEEA) in multiple cancer cell lines along with control. We have also evaluated its effect on different in vivo toxicity parameters. Here, we found that AEEA was found to be most active in most of the cancer cell lines but it significantly induced apoptosis in human breast cancer cell lines by disrupting mitochondrial membrane potential and DNA damage. Moreover, AEEA treatment inhibited migration in both MCF 7 and MDA-MB-231 cells in a dose dependent manner. Further, AEEA possesses robust in vitro antioxidant activity along with high total phenolic and flavonoid contents. In summary, our results indicate that Eclipta alba has enormous potential in complementary and alternative medicine for the treatment of cancer.