Cytotoxic activity of 9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol from Eulophia nuda against human cancer cells

Ethnopharmacological relevance

Eulophia nuda L. (Orchidaceae) is a medicinally important terrestrial orchid used for the treatment of tumours and various health problems by the local healers throughout the Western Ghats region in Maharashtra (India).

Aim of the study

To isolate the active molecule from Eulophia nuda and to study its cytotoxic potential against human cancer cells.

Materials and methods

The crude methanolic extract of Eulophia nuda tubers was fractionated by stepwise gradient of the solvents—chloroform–methanol to isolate the pure compound. Isolated pure compound was assessed for its cytotoxic potential against human breast cancer cell lines, MCF-7 and MDA-MB-231 using MTT assay. Structure elucidation of the isolated active compound was carried out by extensive spectroscopic analysis including ¹H NMR, ¹³C NMR, NOESY, COSY, LC–MS and IR.

Results

The isolated active molecule was identified as phenanthrene derivative 9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol. This compound showed good antiproliferative activity against human breast cancer cell lines MCF-7 (91%) and MDA-MB-231 (85%) at 1000 μg/ml concentration.

Conclusion

9,10-Dihydro-2,5-dimethoxyphenanthrene-1,7-diol from Eulophia nuda tubers showed good growth suppressive effect against human cancer cell lines MCF-7 and MDA-MB-231 making it a potential biomolecule against human cancer.     

Cytotoxic polyphenols against breast tumor cell in Smilax china L.

Ethnopharmacological relevance

Smilax china L., referred to ‘Ba Qia’ (or ‘Jin Gang Teng’) in China, is a small vine that grows in the southern parts of China. The roots and tubers of S. china L. have been applied not only as traditional Chinese medicine (TCM) for treatment of diuretic, rheumatic arthritic, detoxication, lumbago, gout, tumor, and inflammatory diseases, but also as food in some area of China.

Aim of study

To investigate the breast tumor cell toxic components in S. china L. continuously and systematically.

Materials and methods

Three fractions and six polyphenols were isolated from roots and tubers of S. china L. under bioassay-guided screenings. The structures of six compounds were elucidated by spectroscopic methods and comparison with published data. Their breast tumor cytotoxicity and apoptosis of purified components were performed.

Results

Six polyphenols were obtained on the basis of a bioassay-guided separation of the ethyl acetate extract, and their breast tumor cytotoxic activities were tested. They showed anti-tumor activities against MCF-7 and MDA-MB-231 with IC50 value of 2.1–38.9 μg/mL, and can induce apoptosis for MCF-7 and MDA-MB-231.

Conclusions

Among these six polyphenols, five (1, 3–6) were reported for the 1st time with in vitro activities on anti-breast tumor cell. It is likely that these polyphenols are the active components of S. china L. responsible for the anti-breast tumor cell activities.     

In vitro anti-breast cancer activity of ethanolic extract of Wrightia tomentosa: Role of pro-apoptotic effects of oleanolic acid and urosolic acid

Ethnopharmacological relevance

Wrightia tomentosa Roem. & Schult. (Apocynaceae) is known in the traditional medicine for anti-cancer activity along with other broad indications like snake and scorpion bites, renal complications, menstrual disorders etc. However, the anti-cancer activity of this plant or its constituents has never been studied systematically in any cancer types so far.

Aim of the study

To evaluate the anti-cancer activities of the ethanolic extract of W. tomentosa and identified constituent active molecule(s) against breast cancer.

Material and methods

Powdered leaves of W. tomentosa were extracted with ethanol. The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa were tested for its anti-proliferative and pro-apoptotic effects in breast cancer cells MCF-7 and MDA-MB-231.

Results

The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa inhibited the proliferation of human breast cancer cell lines, MCF-7 and MDA-MB-231. The fraction F-4 obtained from hexane fraction inhibited proliferation of MCF-7 and MDA-MB-231 cells in concentration and time dependent manner with IC₅₀ of 50 μg/ml and 30 μg/ml for 24 h, 28 μg/ml and 22 μg/ml for 48 h and 25 μg/ml and 20 μg/ml for 72 h respectively. The fraction F-4 induced G1 cell cycle arrest, reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential and subsequent apoptosis. Apoptosis is indicated in terms of increased Bax/Bcl-2 ratio, enhanced Annexin-V positivity, caspase 8 activation and DNA fragmentation. The active molecule isolated from fraction F-4, oleanolic acid and urosolic acid inhibited cell proliferation of MCF-7 and MDA-MB-231 cells at IC₅₀ value of 7.5 μM and 7.0 μM respectively, whereas there is devoid of significant cell inhibiting activity in non-cancer originated cells, HEK-293. In both MCF-7 and MDA-MB-231, oleanolic acid and urosolic acid induced cell cycle arrest and apoptosis as indicated by significant increase in Annexin-V positive apoptotic cell counts.

Conclusion

Our results suggest that W. tomentosa extracts has significant anti-cancer activity against breast cancer cells due to induction of apoptosis pathway. Olenolic and urosolic acid are important constituent molecules in the extract responsible for anti-cancer activity of W. tomentosa.     

Water extract of Rheum officinale Baill. induces apoptosis in human lung adenocarcinoma A549 and human breast cancer MCF-7 cell lines

Ethnopharmacological relevance

Rheum officinale Baill. (Da Huang) is one of the herbs commonly used in traditional Chinese medicine formulae against cancer. The traditional decoction is similar to the water extract used in the present study.

Aim of the study

The water extract of Da Huang was investigated to see if it possesses anticancer effects through apoptotic pathways.

Materials and methods

Human lung adenocarcinoma A549 and human breast cancer MCF-7 cell lines were treated with different concentrations of Da Huang water extract at different time intervals. Growth inhibition was detected by MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] and colony formation assays; apoptosis was detected by cell morphologic analysis, DNA fragmentation analysis and COMET assay.

Results

Da Huang water extract was found to have significant growth inhibitory effects on both A549 and MCF-7 cell lines with IC₅₀ values 620 ± 12.7 and 515 ± 10.1 μg/ml, respectively. Growth inhibitory effects were dose- and time-dependent. A significant decrease in cell number, DNA fragmentation and single DNA strand breakages were observed in the Da Huang water extract treated A549 and MCF-7 cells.

Conclusions

This suggests that the water extract of Da Huang exerts potential anticancer activity through growth inhibition and apoptosis on MCF-7 and A549 cells lines.     

In vivo pharmacokinetics of bakuchiol after oral administration of bakuchiol extraction in rat plasma

Ethnopharmacological relevance

Psoralea corylifolia L. (Fabaceae) was a traditional Chinese medicine for the treatment of various skin diseases such as psoriasis, vitiligo and chronic graft-versus-host, and has been proved to show anticancer, cytotoxic, anti-bacterial, cardiac, diaphoretic, diuretic, stimulant, aphrodisiac and tonic effects. Bakuchiol was one of the main active ingredients of this traditional Chinese medicine.

Aim of the study

In this paper, pharmacokinetic study was conducted to obtain pharmacokinetic parameters of bakuchiol.

Materials and methods

Bakuchiol was enriched using resin inform the ethanol extract of Psoralea corylifolia L., HPLC-UV was used to determine the concentration of bakuchiol in rat plasma at different time points after administration. The main pharmacokinetic parameters of bakuchiol in rat were obtained based on the analysis of the plasma sample.

Results

The pharmacokinetics of bakuchiol was fitted with a two-compartment model and it was eliminated relative slowly in rats.

Conclusions

The HPLC-UV method was successfully applied to study the pharmacokinetics of bakuchiol in rats.     

The genus Clematis (Ranunculaceae): Chemical and pharmacological perspectives

Ethnopharmacological relevance

Twenty six species of the genus Clematis (Ranunculaceae) have been traditionally used in various systems of medicine for the treatment of ailments such as nervous disorders, syphilis, gout, malaria, dysentry, rheumatism, asthma, and as analgesic, anti-inflammatory, diuretic, antitumour, antibacterial and anticancer.

Aim of the review

To emphasize on ethnopharmacology, chemical constituents, pharmacology, toxicology and clinical studies of various species of the genus Clematis.

Materials and methods

The available information on Clematis species was collected through electronic search of major scientific databases.

Results

A survey of literature revealed that triterpene saponins, alkaloids, flavonoids, lignans, steroids, coumarins, macrocyclic compounds, phenolic glycosides, anemonin and volatile oils constitute major classes of chemical constituents in the genus Clematis. Preliminary analgesic, anticancer, anti-inflammatory, diuretic, antiarthritis, hepatoprotective, hypotensive and HIV-1 protease inhibitor activity studies have been carried out on crude extracts of 26 traditionally used and medicinally promising species of Clematis genus.

Conclusions

The species of the genus Clematis emerged as good source of traditional medicine for the treatment of various ailments. Although few experimental studies validated their traditional claims, but employed uncharacterized crude extracts. Such Clematis species need to be explored properly following bioactivity-directed fractionation with a view to isolate bioactive constituents, and to evaluate their possible mode of actions. These species hold great potential for detailed clinical studies so that these could be exploited as potential drugs. The review will help researchers to select medicinally potential species of Clematis genus for future research.     

Antiproliferative and apoptosis inducing activity of Markhamia tomentosa leaf extract on HeLa cells

Ethnopharmacological relevance

Markhamia tomentosa (Benth) K. Schum ex. Engl. (Bignoniaceae), a tree widely dispersed in West Tropical Africa, is used traditionally to treat various diseases as it possesses antimicrobial, antioxidant, analgesic, anticancer and anti-inflammatory activities.

Materials and methods

This study evaluates the cytotoxic effect and underlying mechanisms of the ethanolic extract of Markhamia tomentosa on HeLa and MCF-7 cancer cell lines and non-cancerous Vero cell line. Brine shrimp lethality test was used for preliminary screening. Cytotoxicity was determined using the MTT assay and IC₅₀ was calculated. Effect of Markhamia tomentosa on the cell cycle was monitored by flow cytometry and the apoptosis-induction capability confirmed by exposure of phosphatidylserine to the outer leaflet of the plasma membrane. Loss of mitochondrial membrane potential was analysed by flow cytometry using JC-1.

Results

Markhamia tomentosa was toxic to brine shrimps with LD₅₀ of 31.62 µg/ml. Cell viability and growth of HeLa cells was inhibited by the extract with an IC₅₀ of 189.1±1.76 µg/ml at 24 h post treatment. However, no cytotoxic effect was observed in MCF-7 and Vero cell lines. The extract induced cell cycle arrest in HeLa cells in the G₀/G₁ phase resulting in cell death after 24 h exposure. Induction of apoptosis in HeLa cells was substantiated by Annexin V-FITC/PI double staining showing phosphatidylserine translocation and depolarisation of the mitochondrial membrane potential by flow cytometry of JC-1 stained cells.

Conclusion

The ethanolic extract of Markhamia tomentosa induces G₀/G₁ in HeLa cells followed by induction of the intrinsic pathway of apoptosis.     

Anti-breast cancer effects and mechanisms of Xihuang pill on human breast cancer cell lines

Objective

To investigate the anti-breast cancer (BC) effects and mechanisms of action of Xihuang pill (XHP) by conducting in vitro experiments on human BC cell lines.

Methods

Two human BC cell lines (MCF-7 and MDA- MB231) were cultured and treated with XHP. Cell viability was detected using the 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was used to measure the cell cycle and apoptosis. The cell cycle was analyzed with propidium iodide staining. Apoptosis was evaluated using the Annexin V-fluorescein isothiocyanate/propidium iodide method. Western blotting was used to analyze the expression of estrogen receptor (ER)-α and ER-β.

Results

XHP had growth-inhibitory effects on MCF-7 and MDA-MB231 cells with a half-maximal inhibitory concentration (IC50) of 10.14 mg/mL (MCF-7) and 8.98 mg/mL (MDA-MB231). Apoptosis was induced to some extent. Certain changes in the ER were caused. Upregulation of ER-α protein was found in MCF-7 cells. ER-β expression in MDA-MB231 cells was increased. Cell-cycle arrest was not observed in the two BC cell lines. ER-β expression in MCF-7 cells was unchanged. No ER-α expression was shown in MDA-MB231 cells.

Conclusion

These data suggest that XHP can affect cell viability and cause apoptosis, but that the cell cycle is not blocked. XHP has a certain impact on ER expression, but its mechanisms of action of anti-BC effects may not be due to regulation of ER expression.     

Differential signaling involved in Sutherlandia frutescens-induced cell death in MCF-7 and MCF-12A cells

Ethnopharmacological relevance

The scientific study of natural products traditionally used in anticancer preparations has yielded several therapeutically relevant compounds. One of these traditional preparations with potentially beneficial properties is aqueous extracts of Sutherlandia frutescens, a shrub indigenous to the Western Cape region of South Africa. The aims of this study were to evaluate in vitro efficacy of these preparations on the MCF-7 breast adenocarcinoma and MCF-12A non-tumorigenic cell lines in terms of cell proliferation, cell morphology and possible induction of cell death.

Materials and methods

Crystal violet staining was used to evaluate cell proliferation, light-and fluorescence microscopy were used to investigate both intracellular and extracellular morphological features of apoptosis and autophagy (e.g. membrane blebbing, condensed chromatin and intracellular lysosomes), while flow cytometry quantified cell cycle changes and induction of apoptosis through analysis of the flip-flop translocation of phosphatidylserine.

Results

Crystal violet staining showed a time- and dose specific response to aqueous Sutherlandia frutescens extracts, revealing exposure to 1 mg/ml aqueous extract for 48 h to be ideal for comparing the differential effects of Sutherlandia frutescens in the MCF-7 and MCF-12A cell lines. Microscopy showed distinct morphological changes with hallmarks of apoptosis being observed in both cell lines. Flow cytometry revealed a decrease in actively cycling cells in both cell lines, and a 4.36% increase in phosphatidylserine translocation in the MCF-7 cell line, indicative of apoptosis induction, while fluorescence microscopy showed evidence of the induction of autophagy.

Conclusions

Analyses revealed the carcinogenic MCF-7 cell line to be more susceptible to the cytostatic and cytotoxic effects of aqueous extracts of Sutherlandia frutescens when compared to the non-tumorigenic MCF-12A cell line, thus warranting further research into the exact cellular mechanisms involved and the possible synergistic activities of Sutherlandia frutescens ingredients.     

Bioactive Lignans from Zanthoxylum alatum Roxb. stem bark with cytotoxic potential

Ethanopharmacological relevance

Zanthoxylum alatum is used in traditional medicinal systems for number of disorders like cholera, diabetes, cough, diarrhea, fever, headache, microbial infections, toothache, inflammation and cancer. The aim of the present study was to evaluate Zanthoxylum alatum stem bark for its cytotoxic potential and to isolate the bioactive constitiuents.

Material and methods

Cytotoxicity of the different extracts and isolated compounds was studied on lung carcinoma cell line (A549) and pancreatic carcinoma cell line (MIA-PaCa) using MTT assay. Isolation of compounds from most active extract (petroleum ether) was done on silica gel column. Structure elucidation was done by using various spectrophotometric techniques like UV, IR, ¹H NMR, ¹³C NMR and mass spectroscopy. The type of cell death caused by most active compound C was explored by fluorescence microscopy using the acridine orange/ethidium bromide method.

Result

Petroleum ether extract of plant has shown significant cytotoxic potential. Three lignans sesamin (A), kobusin (B), and 4'O demethyl magnolin (C) has been isolated. All lignans showed cytotoxic activities in different ranges. Compound C was the novel bioactive compound from a plant source and found to be most active. In apoptosis study, treatment caused typical apoptotic morphological changes. It enhances the apoptosis at IC₅₀ dose (21.72 µg/mL) however showing necrotic cell death at higher dose after 24 h on MIA-PaCa cell lines.

Conclusion

Petroleum ether extract (60–80 °C) of Zanthoxylum alatum has cytotoxic potential. The lignans isolated from the petroleum ether extract were responsible for the cytotoxic potential of the extract. 4'O demethyl magnolin was novel compound from Zanthoxylum alatum. Hence the Zanthoxylum alatum can be further explored for the development of anticancer drug.     

Isolation and identification of antibacterial and cytotoxic compounds from the leaves of Muntingia calabura L.

Ethnopharmacological relevance

Muntingia calabura (Elaeocarpaceae) is one of the most common roadside trees in Malaysia. Its leaves, barks, flowers and roots have been used as a folk remedy for the treatment of fever, incipient cold, liver disease, as well as an antiseptic agent in Southeast Asia. The aim of this study is to isolate and identify the antibacterial and cytotoxic compounds from the leaves of Muntingia calabura L.

Materials and methods

Antibacterial and cytotoxic activities were determined by micro-broth dilution and MTT assays, respectively. Seven fractions (F1–F7), three flavones and a chalcone were isolated from the active EtOAc extract using bioassay-guided screening. The structures of four compounds were elucidated by spectroscopic methods and compared with published data. The compounds were further tested for their antibacterial and cytotoxic activities.

Results

Three flavones and a chalcone [5,7-dihydroxy-3,8-dimethoxyflavone (1), 2′,4′-dihydroxychalcone (2), 5-hydroxy-3,7-dimethoxyflavone (3) and 3,5,7-trihydroxy-8-methoxyflavone (4)] were isolated from the active fraction F5 of EtOAc extract. Compounds 1 and 3 were isolated for the first time from Muntingia calabura L. Antibacterial activity indicates that compound 2 exhibited the most significant activity with MIC value of 50 μg/mL and 100 μg/mL against MSSA and MRSA, respectively. Cytotoxic activity indicates that compounds 2 and 3 exhibited very strong activity against HL60 with IC₅₀ values of 3.43 μg/mL and 3.34 μg/mL, respectively.

Conclusion

The antibacterial activity of the leaves of Muntingia calabura L. is ascribable to the active compound 2 while the cytotoxic activity is ascribable to the active compounds 2 and 3.     

Withanolides from Whitania aristata and their diuretic activity

Aim of the study

Withania aristata is an endemic plant used traditionally in Canary Islands as a diuretic. In this paper, we report on this pharmacological activity in several extracts of the dry vegetal material collected and the identification and diuretic activity of two withanolides, one of them previously not reported, isolated from the most active fraction.

Material and methods

Four Whitania aristata extracts at 100 mg/kg were orally administered to laboratory animals to evaluate their diuretic activity. From the most active fraction, two withanolides were isolated. Both and a mixture of them at 5 and 10 mg/kg were analyzed too as diuretics. Water excretion rate and content of Na⁺ and K⁺ electrolytes were measured in the urine of saline-loaded animals.

Results

Whitania aristata water fraction, the two withanolides and the mixture of these compounds displayed high diuretic activity, with a significant excretion of sodium and potassium ions in laboratory animals.

Conclusions

This research supports the ethno-medicinal use of Whitania aristata as diuretic. This activity seems to be associated to the presence of a new type of natural diuretic agents, such as withaferin A and witharistatin.     

Anticancer potential of aqueous extract of alocasia macrorrhiza against hepatic cancer in vitro and in vivo

Ethnopharmacological relevance

Alocasia macrorrhiza has been used as a folk medicine for cancer treatment in the Southwest of China.

Aim of the study

The purpose of this study is to confirm the anticancer activity of aqueous extract of alocasia macrorrhiza against hepatic cancer and to elucidate its mechanism of action.

Materials and methods

Human normal liver cells and hepatocellular carcinoma cells were tested in vitro for cytotoxicity, colony formation inhibition, EdU incorporation, AO/EB staining apoptotic cells, apoptotic DNA fragmentation, and cell cycle distribution in response to alocasia macrorrhiza extract. The mRNA and protein expressions of PPARγ, Cyclin D1, Rb, P21, Bax, Bcl-2 and caspase-3 were detected through RT-PCR and Western blotting; the tumor growth inhibition in vivo was tested by oral administration of the extract.

Results

Alocasia macrorrhiza aqueous extract exhibited proliferation inhibition and apoptosis effects on human hepatocellular carcinoma cells in vitro, inhibited hepatoma growth in vivo.

Conclusion

Alocasia macrorrhiza extract has potential cytotoxic and apoptotic effect on human hepatocellular carcinoma cells and inhibits hepatoma growth in vivo, its mechanism of action might be associated with the inhibition of DNA synthesis, cell cycle (G₀/G₁) arrest, apoptosis induction through up-regulation the mRNA and protein expressions of PPARγ, Rb, Bax and capase-3genes and down-regulation of the expressions of Cyclin D1 and Bcl-2 genes.     

Tumoral cytotoxic and antioxidative phenylpropanoid glycosides in Smilax riparia A. DC

Ethnopharmacological relevance

Smilax riparia A. DC., known as “Niu-Wei-Cai” in China, is distributed through the south and middle of China. The roots and rhizomes of Smilax riparia have been used not only as traditional Chinese medicines (TCMs) for the treatment of bronchitis, lumbago of renal asthenia, traumatic injury, asthenia edema, and cancer but also as edible wild herbs in some areas of China.

Aim of the study

To identify the phytochemicals in the roots and rhizomes of Smilax riparia and to investigate their antioxidant activities and cytotoxicities toward several tumor cell lines.

Materials and methods

Four fractions and five phenylpropanoid glycosides were obtained from roots and rhizomes of Smilax riparia under bioassay-guided screenings. The structures of five compounds were elucidated by spectroscopic methods and compared with published data. We evaluated their antioxidant activities and their cytotoxicities on five cancer cell lines: human promyelocytic leukemia (HL-60), human hepatocellular carcinoma (SMMC-7721), human lung cancer (A-549), human breast cancer (MCF-7), and human colon cancer (SW480).

Results

Of the five glycosides, one new compound (3, smilaside P) was isolated from an EtOAc fraction. Compound 1 was cytotoxic toward HL-60, SMMC-7721, A-549, MCF-7, and SW480 (IC₅₀ 2.70, 3.80, 11.91, 3.79, and 3.93 μM, respectively). Moreover, compounds 1–3 showed moderate scavenging activities against the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical (IC₅₀ 339.58, 330.66, 314.49 μM, respectively).

Conclusions

Five phenylpropanoid glycosides were reported for the first time from this TCM. Each was studied, as observed here for the first time, in the cytotoxic experiments toward HL-60, SMMC-7721, and SW480 cell lines. Compound 1, bearing three feruloyl groups and three acetyl groups, had the greatest cytotoxicity toward the five tumor cell lines. Compounds 1–3 showed moderate antioxidant activities. All results reflect that compounds 1–3 are cytotoxic for a wide variety of cancer cell lines of differing tissue origins and that the cytotoxicities of these compounds may be related to their antioxidant activities.     

Antibacterial,cytotoxic activities and chemical composition of fruits of two Cameroonian Zanthoxylum species

Ethnopharmacological relevance

Zanthoxylum leprieurii (Syn. Fagara leprieurii) is a plant extensively used by traditional healers in Cameroon for the treatment of stomach disorders, gonorrhea, intestinal parasites and sterility. The infusion from the fruit is taken in Cameroon for the treatment of sickle cell anemia, as well. Similarly, the roots of Zanthoxylum zanthoxyloides (Syn. Fagara zanthoxyloides) are also used for wound dressing, sickle cell anemia and as pain reliever, in addition to the uses mentioned for Zanthoxylum leprieurii.

Aim of the study

To scientifically validate their traditional use, the in vitro antimicrobial and anticancer assays were performed. In addition, chemical compositions of their fruit extracts and essential oils were also studied.

Material and methods

The chemical compositions of their essential oils and methanol extracts were studied. GC and GC–MS were used for analyzing the essential oils while various chromatographic methods were used to isolate the pure compounds from methanol extracts. MTT assay was used for the cytotoxic studies of methanol extracts, their fractions and some pure compounds. Antimicrobial activity of methanol extracts, some isolated compounds as well as essential oils was tested against a panel of human pathogenic bacteria by diffusion and dilution methods.

Results

The principal constituents of the essential oil of Zanthoxylum zanthoxyloides were identified as citronellol and geraniol whereas Zanthoxylum leprieurii was rich in E-β-ocimene. Furthermore, we report for the first time, the presence of 7,8-dimethoxycoumarin and sinapic acid in the methanol extract of Zanthoxylum leprieurii. In vitro bioassays reveal that the methanol extracts, essential oil and some of the isolated compounds from fruits of both the plants exhibit moderate anticancer and antimicrobial activities.

Conclusion

Altogether, the present findings justify the traditional use of Zanthoxylum zanthoxyloides and Zanthoxylum leprieurii in the treatment of stomach disorders and cancer disease. The antimicrobial properties in the essential oil of Zanthoxylum zanthoxyloides are of additional significance.     

Dillenia suffruticosa exhibited antioxidant and cytotoxic activity through induction of apoptosis and G2/M cell cycle arrest

Ethnopharmacological relevance

Dillenia suffruticosa (Family: Dilleniaceae) locally known as Simpoh air has been reported to be used traditionally to treat cancerous growth. Therefore, the present study was attempted to investigate the antioxidant and cytotoxic properties of different parts (root, flower, fruit and leaf) of D. suffruticosa extracts.

Methods and materials

In this study, direct solvent extraction (aqueous and methanol) from different parts of D. suffruticosa (root, flower, fruit and leaf) were carried out. Antioxidant activities of D. suffruticosa extract were determined by using DPPH, ABTS FRAP and β-carotene bleaching assays. Cytotoxicity and cell cycle arrest of the active extract were determined using MTT assay and flow cytometer, respectively. Sequential solvent extraction (hexane, DCM, EtOAc, and MeOH) were also carried out in root of D. suffruticosa to further evaluate the antioxidant and cytotoxic activity of the different solvent extracts.

Results

Methanol (MeOH) root extract showed the highest TPC, antioxidant and cytotoxic activities (especially towards HeLa) compared to others (P<0.05). Based on the results, sequential solvent extraction (hexane, DCM, EtOAc and MeOH) was carried out in the roots of D. suffruticosa. MeOH extract exhibited the highest antioxidant activities among others and significantly correlated (P<0.05) with TPC, suggesting the important contribution of phenolic compounds to its antioxidant activity. On the other hand, the DCM and EtOAc exhibited higher cytotoxic activity to selected cancer cells (HeLa, MCF-7, MDA-MB-231, A549 and HT29) compared to others. In short, there is no established correlation between antioxidant and cytotoxic activities of D. suffruticosa extracts indicating that an agent with high antioxidant activities will not necessarily possesses good cytotoxic activities in return. Qualitative phytochemical screening of D. suffruticosa extracts suggested the presence of saponins, triterpenes, sterols, and polyphenolic compounds which are believed to contribute to the cytotoxic activities.

Conclusion

It is suggested that the cytotoxicity of the active extracts in HeLa was due to the induction of apoptosis and cell cycle arrest at G₂/M.     

Diuretic properties of Orthosiphon stamineus Benth

Ethnopharmacological relevance

Orthosiphon stamineus has been used in traditional medicine for centuries especially to treat diseases of the urinary system.

Aim of the study

To investigate the diuretic activity, to elucidate its possible mechanism and to evaluate the renal effects of Orthosiphon stamineus extract.

Materials and methods

Water extracts were administered orally at doses of 5 and 10 mg/kg to Sprague–Dawley rats and the control groups were given commercial diuretic drugs either furosemide or hydrochlorthiazide at 10 mg/kg. Urine volume, urine pH, urine density and urine electrolytes were determined every hour for 4 h. Blood was assayed for glucose, albumin, blood urea nitrogen (BUN) and creatinine.

Results

O. stamineus extract exhibited dose-dependent diuretic activity. However, excretion of Na⁺ and Cl⁻ was not markedly elevated, but urinary excretion of K⁺ was significantly increased. O. stamineus extracts slightly increased the serum BUN, creatinine and blood glucose level. Although these levels were statistically significant when compared to control, these levels were still within normal range.

Conclusions

O. stamineus exhibited diuretic activity, but was less potent than furosemide and hydrochlorothiazide. Care should be taken when consuming this herb as slight increase of kidney function enzymes was recorded.     

Evaluation of diuretic activity of Amaranthus spinosus Linn. aqueous extract in Wistar rats

Ethnopharmacological relevance

Traditional Siddha medicine literature claims that the Amaranthus spinosus Linn. (family: Amaranthaceae) whole plant possesses diuretic property.

Aim of the study

To evaluate the diuretic potential of Amaranthus spinosus aqueous extract (ASAE) in rats.

Material and methods

Different concentrations of ASAE (200, 500, 1000, 1500 mg/kg), thiazide (10 mg/kg) and vehicle were orally administered to rats (n = 6 animals per group) and their urine output was collected after 24 h. Volume, pH, Na⁺, K⁺ and Cl⁻ concentrations of urine were estimated.

Results

ASAE produced increase in Na⁺, K⁺, Cl⁻ excretion, caused alkalinization of urine, showed strong saluretic activity and carbonic anhydrase inhibition activity. These effects were observed predominantly at 500 mg/kg dose and there was no dose–response relationship.

Conclusion

Our study strongly suggests that the Amaranthus spinosus is acting as a thiazide like diuretic with carbonic anhydrase inhibitory activity which restates the claim as diuretic herb in Siddha medicine.     

Rhizoma Paridis ethanol extract selectively inhibits the proliferation of HUVECs comparing to Lovo cells and shows anti-angiogenesis effects in a mouse model

Ethnopharmacological relevance

Rhizoma Paridis, a traditional Chinese Medicine, was identified to be cytotoxic to cancer cells. The present study was designed to investigate the potential anti-angiogenic and antitumor effect of the ethanol extract of Rhizoma Paridis (RPE) in vitro and in vivo.

Materials and methods

The cytotoxic effect of RPE against human colon cancer Lovo cells and human umbilical vein endothelial cells (HUVECs) was examined using MTT assay. We also tested the effect of RPE on tube formation, migration, apoptosis and cell cycle of HUVECs. Moreover, Lovo subcutaneous xenograft was applied to study the antitumor and anti-angiogenesis effect of RPE in vivo.

Results

RPE exerted a higher inhibition effect on the proliferation of HUVECs than Lovo cells. The tube formation and cell migration were also significantly inhibited in the presence of RPE in a concentration-dependent manner though the significant inhibition effects were observed at the cytotoxic dose. RPE induced cell apoptosis and G0–G1 cell cycle arrest of HUVECs. In vivo, significant tumor growth inhibition was observed in human colon cancer xenografts established by Lovo cells, accompanying by a marked decrease in MVD.

Conclusions

Our current study exhibited that RPE has a selective cytotoxity against HUVECs comparing to Lovo cells and also demonstrated significant anti-angiogenic effect in vivo.     

In vitro bactericidal activity of diterpenoids isolated from Aframomum melegueta K.Schum against strains of Escherichia coli, Listeria monocytogenes and Staphylococcus aureus

Ethnopharmacological relevance

The ethnobotanical use of Aframomum melegueta in the treatment of urinary tract and soft tissue infection suggested that the plant has antimicrobial activity.

Materials and methods

To substantiate the folkloric claims, an acetone, 50:50 acetone:methanol and 2:1 chloroform:methanol extracts were tested against Escherichia coli K12; acetone extract and the fractions of acetone extracts were tested against Listeria monocytogenes. Bioassay-guided fractionation was performed on the extract using L. monocytogenes as the test organism to isolate the bioactive compounds which were then tested against all the other organisms.

Results

Four known labdane diterpenes (G3 and G5) were isolated for the first time from the rhizomes of A. melegueta and purified. These were tested against E. coli, L. monocytogenes, methicillin resistant Staphylococus aureus (MRSA) and S. aureus to determine antibacterial activity. The result showed that two compounds G3 and G5 exhibited more potent antibacterial activity compared to the current clinically used antibiotics ampicillin, gentamicin and vancomycin and can be potential antibacterial lead compounds. The structure of the labdane diterpenes were elucidated using nuclear magnetic resonance (NMR) spectroscopy and Mass spectrometry. A possible mode of action of the isolated compound G3 and its potential cytotoxicity towards mammalian cells were also discussed.

Conclusion

The results confirmed the presence of antibacterial compounds in the rhizomes of A. melegueta with a favourable toxicity profile which could be further optimized as antibacterial lead compounds.