Medicinal plants used as antitumor agents in Brazil: an ethnobotanical approach

How Should the Worldwide Knowledge of Traditional Cancer Healing Be Integrated with Herbs and Mushrooms into Modern Molecular Pharmacology?

Traditional herbal medicine (THM) is a “core” from which modern medicine has evolved over time. Besides this, one third of people worldwide have no access to modern medicine and rely only on traditional medicine. To date, drugs of plant origin, or their derivates (paclitaxel, vinblastine, vincristine, vinorelbine, etoposide, camptothecin, topotecan, irinotecan, and omacetaxine), are very important in the therapy of malignancies and they are included in most chemotherapeutic regimes. To date, 391,000 plant and 14,000 mushroom species exist. Their medical and biochemical capabilities have not been studied in detail. In this review, we systematized the information about plants and mushrooms, as well as their active compounds with antitumor properties. Plants and mushrooms are divided based on the regions where they are used in ethnomedicine to treat malignancies. The majority of their active compounds with antineoplastic properties and mechanisms of action are described. Furthermore, on the basis of the available information, we divided them into two priority groups for research and for their potential of use in antitumor therapy. As there are many prerequisites and some examples how THM helps and strengthens modern medicine, finally, we discuss the positive points of THM and the management required to transform and integrate THM into the modern medicine practice.

Phytochemical characterization, antioxidant potential and antibacterial activity of the Croton argyrophylloides Muell. Arg. (Euphorbiaceae)

Croton argyrophylloides Muell. Arg., from the Euphorbiaceae family, popularly known as marmeleiro prateado or sacatinga, is a plant from the Caatinga biome commonly found in Brazil's northeastern region. The present study aimed to evaluate the antioxidant activity of the species. The phytochemical study was performed through qualitative analysis of chemical constituents and quantitative determination of the total phenol content through the Folin-Ciocalteu test. The qualitative and quantitative antioxidant tests were performed using the DPPH method (2.2 diphenyl-1-picryl hydrazil) and ferric reducing antioxidant power (FRAP). The minimum inhibitory concentration (MIC) was determined by microdilution in 96-well plates. The ethanolic extract of the leaves of C. argyrophylloides manifested antioxidant action in the quantitative DPPH test with a significant bioactivity of 84.70 AAO% in 500 µg/mL, with an EC50 of 236.79. The content of total phenolic compounds was 946.06 mg of gallic acid equivalents/g of sample, and total flavonoids was 58.11 mg of quercetin equivalents/g of sample, the result obtained for FRAP was 15294.44 µM Trolox/g of sample and ABTS was 718 μM Trolox of sample. The prospecting of the chemical constituents of the leaves of C. argyrophylloides revealed the presence of the main compounds that manifests the antioxidant activity and it was proven by the DPPH method that there is antioxidant activity in the analyzed sample, in addition to demonstrating a significant content of phenolic compounds and total flavonoid content in the species, which corroborates the antioxidant activity of the plant sample. The leaf extracts presented growth inhibition halos of 10 and 12 mm upon Staphylococcus aureus ATCC 25923.

Advancing urban ethnopharmacology: a modern concept of sustainability, conservation and cross-cultural adaptations of medicinal plant lore in the urban environment

The discipline 'urban ethnopharmacology' emerged as a collection of traditional knowledge, ancient civilizations, history and folklore being circulated since generations, usage of botanical products, palaeobotany and agronomy. Non-traditional botanical knowledge increases the availability of healthcare and other essential products to the underprivileged masses. Intercultural medicine essentially involves 'practices in healthcare that bridge indigenous medicine and western medicine, where both are considered as complementary'. A unique aspect of urban ethnopharmacology is its pluricultural character. Plant medicine blossomed due to intercultural interactions and has its roots in major anthropological events of the past. Unani medicine was developed by Khalif Harun Al Rashid and Khalif Al Mansur by translating Greek and Sanskrit works. Similarly, Indo-Aryan migration led to the development of Vedic culture, which product is Ayurveda. Greek medicine reached its summit when it travelled to Egypt. In the past few decades, ethnobotanical field studies proliferated, especially in the developed countries to cope with the increasing demands of population expansion. At the same time, sacred groves continued to be an important method of conservation across several cultures even in the urban aspect. Lack of scientific research, validating the efficiency, messy applications, biopiracy and slower results are the main constrains to limit its acceptability. Access to resources and benefit sharing may be considered as a potential solution. Indigenous communities can copyright their traditional formulations and then can collaborate with companies, who have to provide the original inventors with a fair share of the profits since a significant portion of the health economy is generated by herbal medicine. Search string included the terms 'Urban' + 'Ethnopharmacology', which was searched in Google Scholar to retrieve the relevant literature. The present review aims to critically analyse the global concept of urban ethnopharmacology with the inherent plurality of the cross-cultural adaptations of medicinal plant use by urban people across the world.

Peppers: A "Hot" Natural Source for Antitumor Compounds

Piper, Capsicum, and Pimenta are the main genera of peppers consumed worldwide. The traditional use of peppers by either ancient civilizations or modern societies has raised interest in their biological applications, including cytotoxic and antiproliferative effects. Cellular responses upon treatment with isolated pepper-derived compounds involve mechanisms of cell death, especially through proapoptotic stimuli in tumorigenic cells. In this review, we highlight naturally occurring secondary metabolites of peppers with cytotoxic effects on cancer cell lines. Available mechanisms of cell death, as well as the development of analogues, are also discussed.

Phytochemical Screening and Evaluation of Antioxidant Properties and Antimicrobial Activity against Xanthomonas axonopodis of Euphorbia tirucalli Extracts in Binh Thuan Province, Vietnam

Euphorbia tirucalli is a medicine plant possessing many bioactive properties. This paper focused on phytochemical screening (alkaloid, flavonoid, saponin, tannin, and anthraquinone), quantification of polyphenol and flavonoids, and activating evaluation of antioxidants and antimicrobial properties against Xanthomonas axonopodis of different extracts from Euphorbia tirucalli grown in Binh Thuan, Vietnam. The best activity fraction was used for purification and determining bioactive ingredients. The results showed that the phytochemical study revealed the presence of alkaloids, flavonoids, tannins, and terpenoids in the ethyl acetate fraction. Saponin and anthraquinone did not present in all extracts. The content of polyphenol and flavonoid of Euphorbia tirucalli stem was in the range of 16.65–106.32 mg EqAG/g and 97.97–450.83 μg QE/g. The ethyl acetate fraction showed higher amounts of polyphenol and flavonoids and antimicrobial activity against X. axonopodis than other fractions. The antioxidant (SC50) activity of Euphorbia tirucalli stem was in the range of 12.91 ± 0.70 and 528.33 ± 25.15 μg/mL. At concentrations of 5.0 and 7.5 mg/mL, the diameter of inhibition of the ethyl acetate fraction was 14.33 ± 0.76 mm and 17.87 ± 0.57 mm, respectively. The MIC (minimum inhibitory concentration) was 0.156 mg/mL. Scopoletin, gallic acid, and piperic acid got MICs corresponding to 78, 312, and 312 μg/mL, respectively. Scopoletin, gallic acid, and piperic acid were found in the ethyl acetate fraction of Euphorbia tirucalli and exhibited the treatment of citrus bacteria canker and plant diseases.

Tabebuia impetiginosa: A Comprehensive Review on Traditional Uses, Phytochemistry, and Immunopharmacological Properties

Tabebuia impetiginosa, a plant native to the Amazon rainforest and other parts of Latin America, is traditionally used for treating fever, malaria, bacterial and fungal infections, and skin diseases. Additionally, several categories of phytochemicals and extracts isolated from T. impetiginosa have been studied via various models and displayed pharmacological activities. This review aims to uncover and summarize the research concerning T. impetiginosa, particularly its traditional uses, phytochemistry, and immunopharmacological activity, as well as to provide guidance for future research. A comprehensive search of the published literature was conducted to locate original publications pertaining to T. impetiginosa up to June 2020. The main inquiry used the following keywords in various combinations in titles and abstracts: T. impetiginosa, Taheebo, traditional uses, phytochemistry, immunopharmacological, anti-inflammatory activity. Immunopharmacological activity described in this paper includes its anti-inflammatory, anti-allergic, anti-autoimmune, and anti-cancer properties. Particularly, T. impetiginosa has a strong effect on anti-inflammatory activity. This paper also describes the target pathway underlying how T. impetiginosa inhibits the inflammatory response. The need for further investigation to identify other pharmacological activities as well as the exact target proteins of T. impetiginosa was also highlighted. T. impetiginosa may provide a new strategy for prevention and treatment of many immunological disorders that foster extensive research to identify potential anti-inflammatory and immunomodulatory compounds and fractions as well as to explore the underlying mechanisms of this herb. Further scientific evidence is required for clinical trials on its immunopharmacological effects and safety.

Effects of an ethanolic extract and fractions from Piper glabratum (Piperaceae) leaves on pain and inflammation

In the state of Mato Grosso do Sul, Brazil, Piper glabratum leaves are used as a popular medicine for pain and inflammation. We performed a phytochemical analysis and evaluated the effects of ethanolic extract (EEPG) obtained from leaves of P. glabratum on toxicity as well as the effects of application of the hexanic fraction (HXPG) and the hydroalcoholic fraction (HAPG) obtained from the EEPG on inflammatory parameters and pain in mice. Swiss mice were treated with EEPG (30-300 mg/kg body weight (b.w.)), HXPG (19.5 mg/kg b.w.) or HAPG (83.37 mg/kg b.w.) and then subjected to carrageenan-induced pleurisy and paw oedema tests, the spontaneous pain, and zymosan-induced intra-articular inflammation. Wistar rats were treated with EEPG to assess acute toxicity. Phytochemical analysis of the fractions demonstrated the presence of phytol and mixture of stigmasterol and β-sitosterol in the fractions. In the acute toxicity test, LD50 above 2000 mg/kg b.w. was observed. The treatments reduced oedema, cold and mechanical hyperalgesia, leukocyte migration and protein exudation. The antihyperalgesic and anti-inflammatory properties of EEPG and fractions were demonstrated in the present study. These results from EEPG and HXPG may be related, at least in part, to modulation of the inflammatory mediators by phytol, stigmasterol and β-sitosterol.

The fodder grass resources for ruminants: A indigenous treasure of local communities of Thal desert Punjab, Pakistan

Indigenous people have been using local grasses for rearing their animals for centuries. The present study is the first record of traditional knowledge of grasses and livestock feeding system from the Thal desert in Pakistan. A snowball sampling method was used to identify key participants. Information was collected from the respondents from six districts of Thal Desert through semi-structural questionnaire and site visits. The data was analyzed through Smith's salience index and Composite Salience using ANTHROPAC package in R software. On the whole 61 grasses were recorded from the study area: most of them belong to the Poaceae family (52 species). Based on palatability grasses were categorized into three major groups i.e. (A) High priority, (B) Medium priority and (C) Low priority. Species in Group A, abundantly present in the study area represent a source of highly palatable forage for all ruminants. 232 (141M +91W) local participants were interviewed. Participants were grouped into three major age categories: 20-35 (48 participants), 36-50 (116 participants) and 51-67 years old (68 participants). ANTHROPAC frequency analysis confirmed the Smith's salience index and Composite Salience; Cynodon dactylon was the favorite species (6.46 SI, 0.6460 CS) followed by Cymbopogon jwarancusa (5.133 SI, 0.5133 CS) and Sorghum sp. was the third most salient species (5.121 SI, 0.5121 CS). Grasses were mostly available during the months of August and October and had also ethnoveterinary importance. This document about the traditional feeding of livestock in Thal Desert can underline the importance of conserving a traditional knowledge, which was poorly documented before.

In silico identification of natural products with anticancer activity using a chemo-structural database of Brazilian biodiversity

Cancer is one of the leading causes of death worldwide, and the number of patients has only increased each year, despite the considerable efforts and investments in scientific research. Since natural products (NPs) may serve as suitable sources for drug development, the cytotoxicity against cancer cells of 2221 compounds from the Nuclei of Bioassays, Ecophysiology, and Biosynthesis of Natural Products Database (NuBBE_DB) was predicted using CDRUG algorithm. Molecular modeling, chemoinformatics, and chemometric tools were then used to analyze the structural and physicochemical properties of these compounds. We compared the positive NPs with FDA-approved anticancer drugs and predicted the molecular targets involved in the anticancer activity. In the present study, 46 families comprising potential anticancer compounds and at least 19 molecular targets involved in oncogenesis. To the best of our knowledge, this is the first large-scale study conducted to evaluate the potentiality of NPs sourced from Brazilian biodiversity as anticancer agents, using in silico approaches. Our results provided interesting insights about the mechanism of action of these compounds, and also suggested that their structural diversity may aid structure-based optimization strategies for developing novel drugs for cancer therapy.

Arctium lappa Extract Suppresses Inflammation and Inhibits Melanoma Progression

Background: Arctium lappa has been used as popular medicinal herb and health supplement in Chinese societies. Bioactive components from A. lappa have attracted the attention of researchers due to their promising therapeutic effects. In this study, we investigated the effects of A. lappa hydroalcoholic extract (Alhe) during different models of inflammation, in vivo. Methods: The anti-inflammatory activity was evaluated through the air pouch model. For this, mice received an inflammatory stimulus with lipopolysaccharide (LPS) and were later injected with Alhe. To assess anti-tumoral activity, the animals were inoculated with B16F10 cells and injected with Alhe every 5 days, along the course of 30 days. Controls were submitted to the same conditions and injected with the vehicle. Peritoneal or air pouch fluids were collected to evaluate leukocyte counting or cellular activation via quantification of cytokines and nitric oxide. Results: Alhe injection reduced the neutrophil influx and production of inflammatory mediators in inflammatory foci after LPS or tumor challenges. Furthermore, Alhe injection reduced tumor growth and enhanced mice survival. Conclusions: Collectively, these data suggest that Alhe regulates immune cell migration and activation, which correlates with favorable outcome in mouse models of acute inflammation and melanoma progression.

Ethnobotanic, phytochemical uses and ethnopharmacological profile of genus Cnidoscolus spp. (Euphorbiaceae): A comprehensive overview

The application of medicinal plants are the most important biotechnological alternative in the treatment of numerous diseases, especially in developing countries, such as Brazil. Among them, we specified some specimens of the genus Cnidoscolus used as phytotherapies, with healing properties, analgesic, anti-inflammatory, antibiotic and diuretic, anticancer, among others. Such effects are possibly associated with the presence of terpenoids, alkaloids, coumarins, flavonoids phenolic compounds, among others. Thus, the objective of this work was to evaluate in the literature the studies on the phytochemical, ethnopharmacological and biotechnological applications of this genus, from 1998 to 2017. Among the sixty-one studies reported in this review, ten species are popularly utilized to pharmacological and/or biotechnological applications. Cnidoscolus aconitifolius and Cnidoscolus chayamansa are the most cited species, which were also supported by either animal or cellular investigations indicating some beneficial pharmacological actions like antioxidant, anti-inflammatory and potential cytotoxic activity. The plant parts of this genus under study are important as sources for the isolation and identification of bioactive molecules with biotechnological applications, among the many diseases treated with this phytotherapy. Given these verdicts, ethnopharmacological approaches are significant systematic tools in the determination of plant species that exhibit medicinal and nutritional purposes. The results presented here should further stimulate the development of validation studies to ensure the safe and effective use of these plant species.

Evaluation of the toxicity and anti-inflammatory activities of the infusion of leaves of Campomanesia guazumifolia (Cambess.) O. Berg

ETHNOPHARMACOLOGICAL RELEVANCE

Some species of Campomanesia are used in the folk medicine due to anti-inflammatory, anti-diarrheal, anti-diabetes and hypercholesterolemic. However studies with Campomanesia guazumifolia (Cambess.) O. Berg. are scarce.

AIM OF THE STUDY

This study investigated the anti-inflammatory activity and toxicological profile of infusion obtained from leaves of Campomanesia guazumifolia in mice.

MATERIALS AND METHODS

Leaves infusion of C. guazumifolia was obtained in the proportion of 20 g/L (leaves/water) at 95-100 °C for 10 min in an enclosed container. The acute toxicity of the leaves infusion of C. guazumifolia lyophilized (ICG) was assessed by oral administration to female mice at doses of 500, 1000, 2000, and 5000 mg/kg, and the general behavior and toxic symptoms were observed for 14 days. In the subacute toxicity model, female mice were treated orally with the ICG (250, 500, and 1000 mg/kg) during 28 days, and biochemical, toxic signs and the estrous cycle were evaluated. The anti-inflammatory activity of the ICG (70, 300 and 700 mg/kg) was analyzed using carrageenan-induced pleurisy and inflammatory paw (mechanical and thermal hyperalgesia).

RESULTS

Three flavonoids glycosylated and a cyclohexanecarboxylic acid were identified in the ICG: quercetin pentose, quercetin deoxyhexoside, myricetin deoxyhexoside and quinic acid. No clinical signs of acute toxicity were observed, suggesting that the LD₅₀ (Lethal Dose) is above 5000 mg/kg. Subacute exposure of mice to the ICG did not change significantly the hematological and biochemical parameters as well as histology of organs. The ICG increased the duration of estrous cycle in all phases, showing anti-inflammatory potential by decreasing leukocyte migration, extravasation protein in the pleural cavity and antiedematogenic activity. The ICG treatment at a dose of 700 mg/kg decreased the mechanical hyperalgesia, while at doses of 300 mg/kg and 700 mg/kg, decreased the sensitivity to the cold.

CONCLUSION

The results evidenced the anti-inflammatory potential with low toxicity of infusion of the leaves of C. guazumifolia, supporting the popular use of this species.

Screening of Plants Used as Traditional Anticancer Remedies in Mkuranga and Same Districts, Tanzania, Using Brine Shrimp Toxicity Bioassay

Background

Inadequate specialized cancer hospitals and high costs are contributing factors that delay cancer patients from accessing health care services in Tanzania. Consequently, majority of patients are first seen by Traditional Health Practitioners (THPs) before they access specialized services. This study presents ethnomedical information and preliminary evaluation of 25 plant species claimed by THPs in Mkuranga and Same districts of Tanzania on use for treatment of cancer. Literature search and laboratory investigation results are presented to support evaluation.

Methods. This study was a single disease ethnomedical enquiry focusing on plants being used for cancer treatment

Face-to-face interviews and questionnaires were administered to eight (8) THPs in Mkuranga and Same districts on the claimed plants and their use for management of cancer. Plants were selected based on being frequently mentioned and emphasis given by THPs. Literature search and brine shrimp toxicity (BST) of methanol : dichloromethane (1:1) extracts was used as surrogates to evaluate strength of the claims.

Results

This study reports 25 plant species used by the THPs in two districts of Tanzania. Eight plants (32%) have been reported in the literature to have activity against cancer cells. BST results revealed, 14 (56%) plants exhibited high toxicity against brine shrimps. The most active plants included Croton pseudopulchellus Pax (LC₅₀ 4.2 μg/ml), Dalbergia melanoxylon Guill. & Perr. (LC₅₀ 6.8 μg/ml), Loranthus micranthus Linn (LC₅₀ 4.0 μg/ml), Ochna mossambicensis Klotzsch (LC₅₀ 3.3 μg/ml), and Spirostachys africana Sond. (LC₅₀ 4.4 μg/ml); their toxicity was comparable to that of Catharanthus roseus (L) G. Don. (LC₅₀ 6.7 μg/ml), an established source of anticancer compounds. Nine other plants had LC₅₀ values between (19.8 and 71.6) μg/ml, indicating also potential to yield anticancer.

Conclusion

Literature search and BST results provide a strong support of the potential of the claimed plants to yield active anticancer compounds.

Metabolic profiling and correlation analysis for the determination of killer compounds of proliferating and clonogenic HRT-18 colon cancer cells from Lafoensia pacari

ETHNOPHARMACOLOGICAL RELEVANCE

Lafoensia pacari A. St.-Hil., belonging to the family Lythraceae and popularly known as 'dedaleira' and 'mangava-brava,' is a native tree of the Brazilian Cerrado, and its barks have been traditionally used as a tonic to treat inflammatory conditions, particularly related to gastric ulcers, wounds or fevers and various types of cancer.

AIM OF THE STUDY

We have previously demonstrated the apoptogenic effects of the methanolic extract of L. pacari using various cancer cell lines. In the present study, this extract has been partitioned into fractions to identify the components that might be responsible for the apoptogenic effects using HRT-18 cells, which have been previously demonstrated to be sensitive to this extract.

MATERIALS AND METHODS

A standard methanolic extract was prepared and fractionated by centrifugal partition chromatography. The fractions were submitted to cytotoxicity and clonogenic assays to monitor the effects in parallel with LC-DAD-MS and statistical analyses to suggest the potential bioactive compounds.

RESULTS

Besides ellagic acid, the primary constituent of the plant and also the biomarker of the species, punicalin, pedunculagin and punicalagin isomers, catechin and ellagic acid derivatives were putatively identified.

CONCLUSIONS

The barks of L. pacari are rich in ellagic acid and various hydrolysable tannins, some of which were reported for the first time in this species, such as punicalagin and ellagitannins. This mixture of substances had the ability to kill proliferating cells and abrogate the growth of clonogenic cells in a similar manner shown by the methanolic extract of our previous study. The collective data reported herein suggest that the biological activities of the L. pacari barks used by population to treat cancer conditions are due to the apoptogenic effects promoted by a mixed content of ellagitannins.

Endophytic fungi isolated from medicinal plants: future prospects of bioactive natural products from Tabebuia/Handroanthus endophytes

Medicinal plants are a rich source of natural products used to treat many diseases; therefore, they are the basis for a new drug discovery. Plants are capable of generating different bioactive secondary metabolites, but a large amount of botanical material is often necessary to obtain small amounts of the target substance. Nowadays, many medicinal plants are becoming rather scarce. For this reason, it is important to point out the interactions between endophytic microorganisms and the host plant, because endophytes are able to produce highly diverse compounds, including those from host plants that have important biological activities. Thence, this review aims at presenting the richness in bioactive compounds of the medicinal plants from Tabebuia and Handroanthus genera, as well as important aspects about endophyte-plant interactions, with emphasis on the production of bioactive compounds by endophytic fungi, which has been isolated from various medicinal plants for such a purpose. Furthermore, bio-prospection of natural products synthesized by endophytes isolated from the aforementioned genera used in traditional medicine could be used to treat illnesses.

Hexane partition from Annona crassiflora Mart. promotes cytotoxity and apoptosis on human cervical cancer cell lines

Cervical cancer is the third most commonly diagnosed tumor type and the fourth cause of cancer-related death in females. Therapeutic options for cervical cancer patients remain very limited. Annona crassiflora Mart. is used in traditional medicine as antimicrobial and antineoplastic agent. However, little is known about its antitumoral properties. In this study the antineoplastic effect of crude extract and derived partitions from A. crassiflora Mart in cervical cancer cell lines was evaluated. The crude extract significantly alters cell viability of cervical cancer cell lines as well as proliferation and migration, and induces cell death in SiHa cells. Yet, the combination of the crude extract with cisplatin leads to antagonistic effect. Importantly, the hexane partition derived from the crude extract presented cytotoxic effect both in vitro and in vivo, and initiates cell responses, such as DNA damage (H2AX activity), apoptosis via intrinsic pathway (cleavage of caspase-9, caspase-3, poly (ADP-ribose) polymerase (PARP) and mitochondrial membrane depolarization) and decreased p21 expression by ubiquitin proteasome pathway. Concluding, this work shows that hexane partition triggers several biological responses such as DNA damage and apoptosis, by intrinsic pathways, and was also able to promote a direct decrease in tumor perimeter in vivo providing a basis for further investigation on its antineoplastic activity on cervical cancer.

Cytotoxic effect of Erythroxylum daphnites extract is associated with G1 cell cycle arrest and apoptosis in oral squamous cell carcinoma

Plant-derived molecules showing antineoplastic effects have recently gained increased attention as potential adjuvants to traditional therapies for various cancers. Cerrado biome in Brazil contains high floral biodiversity, but knowledge about the potential therapeutic effects of compounds derived from that flora is still limited. The present study investigated the antineoplastic activity of Erythroxylum daphnites Mart., a Brazilian native plant from Cerrado biome, in the SCC-9 oral squamous cell carcinoma cell line. Cells were treated with various concentrations of hexane extract of Erythroxylum daphnites leaves (EDH) and assessed for cytotoxicity, proliferation, and apoptosis. Thin layer chromatography was conducted to characterize the substances present in EDH. Our results showed that EDH exerted anti-proliferative effects in SCC-9 cells by stabilizing the cell cycle at G1 phase in association with reduced intracellular levels of cyclins D and E and increased level of p21. EDH also demonstrated pro-apoptotic properties, as shown by an increased expression of caspase-3. Triterpenes were the major constituents of EDH. Our findings demonstrated a cytotoxic effect of EDH against SCC-9 cells in vitro mediated by the restraint of cellular proliferation and induction of apoptosis. Taken together, these findings support EDH constituents as potential therapeutic adjuvants for oral cancer.

Anti-inflammatory and toxicological evaluation of essential oil from Piper glabratum leaves

ETHNOPHARMACOLOGICAL RELEVANCE

Although some of the species of the genus Piper exhibit interesting biological properties, studies on Piper glabratum Kunth are very limited.

AIM OF THE STUDY

This study investigated the anti-inflammatory activity and the toxicological profile of the essential oil from P. glabratum leaves (OEPG) in mice.

MATERIALS AND METHODS

The acute toxicity of OEPG was evaluated by oral administration to female mice as single doses of 500, 1000, 2000 or 5000mg/kg/body weight. In the subacute toxicity test, the females received 500 or 1000mg/kg/body weight of OEPG for 28 days. The anti-inflammatory potential of OEPG was evaluated using four models including pleurisy, edema, mechanical hyperalgesia and cold allodynia models in mouse paws.

RESULTS

No clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD₅₀ is greater than 5000mg/kg. The subacute exposure to OEPG produced no significant changes in the hematological or biochemical parameters. Similarly, the histology of the organs and the estrus cycle displayed no marked alterations. OEPG exhibited anti-inflammatory activity as indicated by inhibition of the leukocyte migration (100, 300, 700mg/kg) and the protein extravasation into the pleural exudates (700mg/kg). After intraplantar injection of carrageenan, it was observed that the 700mg/kg dose of OEPG reduced edema formation and decreased the sensitivity to mechanical stimulation and cold.

CONCLUSIONS

These results demonstrate the anti-inflammatory potential of the essential oil of P. glabratum leaves in the absence of toxicity in female mice.

Cytotoxic potential of selected medicinal plants in northeast Brazil

BACKGROUND

Great biodiversity is a highlight of Brazilian flora. In contrast, the therapeutic potentialities of most species used in folk medicine remain unknown. Several of these species are commonly used to treat cancer. In this study, we investigated the cytotoxic activity of 18 plants from 16 families that are found in the northeast region of Brazil.

METHODS

The following species were studied: Byrsonima sericea DC. (Malpighiaceae), Cupania impressinervia Acev. Rodr. var. (revoluta) Radlk (Sapindaceae), Duranta repens Linn. (Verbenaceae), Helicostylis tomentosa (Poepp. & Endl) Rusby (Moraceae), Himatanthus bracteatus (A.DC.) Woodson (Apocynaceae), Ipomoea purga (Wender.) Hayne (Convolvulaceae), Ixora coccinea Linn. (Rubiaceae), Mabea piriri Aubl. (Euphorbiaceae), Miconia minutiflora (Melastomataceae), Momordica charantia L. (Cucurbitaceae), Ocotea glomerata (Nees) Mez (Lauraceae), Ocotea longifolia Kunth (Oreodaphne opifera Mart. Nees) (Lauraceae), Pavonia fruticosa (Mill.) Fawc. & Rendle (Malvaceae), Psychotria capitata Ruiz & Pav. (Rubiaceae), Schefflera morototoni (Aubl.) Maguire, Steyerm. & Frodin (Araliaceae), Solanum paludosum Moric. (Solanaceae), Xylopia frutescens Aubl. (Annonaceae) and Zanthoxylum rhoifolium Lam. (Rutaceae). Their dried leaves, stems, flowers or fruits were submitted to different solvent extractions, resulting in 55 extracts. After incubating for 72 h, the cytotoxicity of each extract was tested against tumor cell lines using the alamar blue assay.

RESULTS

The B. sericea, D. repens, H. bracteatus, I. purga, I. coccinea, M. piriri, O. longifolia and P. capitata extracts demonstrated the most potent cytotoxic activity. The chloroform soluble fractions of D. repens flowers and the hexane extract of I. coccinea flowers led to the isolation of quercetin and a mixture of α- and β-amyrin, respectively, and quercetin showed moderate cytotoxic activity.

CONCLUSION

The B. sericea, D. repens, H. bracteatus, I. purga, I. coccinea, M. piriri, O. longifolia and P. capitata plants were identified as having potent cytotoxic effects. Further investigations are required to determine the mechanisms of cytotoxicity exhibited and their in vivo activities. This work reinforces the need to understand the therapeutics potentialities of Brazilian medicinal plants.

Euphorbia tirucalli modulates gene expression in larynx squamous cell carcinoma

BACKGROUND

Some plants had been used in the treatment of cancer and one of these has attracted scientific interest, the Euphorbia tirucalli (E. tirucalli), used in the treatment of asthma, ulcers, warts has active components with activities scientifically proven as antimutagenic, anti-inflammatory and anticancer.

METHODS

We evaluate the influence of the antitumoral fraction of the E. tirucalli latex in the larynx squamous cell carcinoma (Hep-2), on the morphology, cell proliferation and gene expression. The Hep-2 cells were cultivated in complete medium (MEM 10 %) and treated with E. tirucalli latex for 1, 3, 5 and 7 days. After statistically analyzing the proliferation of the tested cells, the cells were cultivated again for RNA extraction and the Rapid Subtractive Hybridization (RaSH) technique was used to identify genes with altered expression. The genes found using the RaSH technique were analyzed by Gene Ontology (GO) using Ingenuity Systems.

RESULTS

The five genes found to have differential expression were validated by real-time quantitative PCR. Though treatment with E. tirucalli latex did not change the cell morphology in comparison to control samples, but the cell growth was significantly decreased. The RaSH showed change in the expression of some genes, including ANXA1, TCEA1, NGFRAP1, ITPR1 and CD55, which are associated with inflammatory response, transcriptional regulation, apoptosis, calcium ion transport regulation and complement system, respectively. The E. tirucalli latex treatment down-regulated ITPR1 and up-regulated ANXA1 and CD55 genes, and was validated by real-time quantitative PCR.

CONCLUSIONS

The data indicate the involvement of E. tirucalli latex in the altered expression of genes involved in tumorigenic processes, which could potentially be applied as a therapeutic indicator of larynx cancer.

Bioactive Properties of Tabebuia impetiginosa-Based Phytopreparations and Phytoformulations: A Comparison between Extracts and Dietary Supplements

Tabebuia impetiginosa (Mart. ex DC.) Standl. has been used in traditional medicine for many centuries, being nowadays marketed as dried plant material (inner bark) for infusions, pills, and syrups. The main objective of the present work was to validate its popular use through the bioactivity evaluation of the inner bark (methanolic extract and infusion) and of two different formulations (pills and syrup) also based on the same plant-material. The antioxidant activity was evaluated by in vitro assays testing free radical scavenging activity, reducing power and inhibition of lipid peroxidation in brain homogenates. The cytotoxicity was determined in four human tumor cell lines (MCF-7, NCI-H460, HeLa and HepG2, and also in non-tumor cells (porcine liver primary cells, PLP2)). Furthermore, the sample was chemically characterized regarding free sugars, organic acids, fatty acids, and tocopherols. Syrup and methanolic extract showed the highest antioxidant activity, related to their highest amount of phenolics and flavonoids. Methanolic extract was the only sample showing cytotoxic effects on the tested human tumor cell lines, but none of the samples showed toxicity in PLP2. Glucose and oxalic acid were, respectively, the most abundant sugar and organic acid in the sample. Unsaturated predominated over the saturated fatty acids, due to oleic, linoleic, and linolenic acids expression. α- and γ-Tocopherols were also identified and quantified. Overall, T. impetiginosa might be used in different phytoformulations, taking advantage of its interesting bioactive properties and chemical composition.

Cytotoxicity and apoptogenic effects of Lafoensia pacari

ETHNOPHARMACOLOGICAL RELEVANCE

The stem barks of Lafoensia pacari have been traditionally used not only by South Amerindians but also by Brazilian and Paraguayan populations for treating a variety of unhealthy conditions to which their biological potential has been scientifically documented in several reports over the last decade. Although its anticancer usage is also popular, no scientific support for such activity has been found.

AIM

To provide scientific evidence for the anticancer popularity of Lafoensia pacari.

MATERIALS AND METHODS

Extracts prepared according to the popular use along with a methanol extract and its four fractions were produced from Lafoensia pacari stem barks. The chromatogram profile of each one was obtained by HPLC. Several tumor cell lines were exposed to these solutions in in vitro assays and the effects evaluated by morphological, growth, and cell cycle status changes.

RESULTS

High toxicity determined by the lactate dehydrogenase levels with a significant drop in the cell proliferation index were found for all cell lines included in this study after exposition to Lafoensia pacari extract and fractions. The morphological features along with the expression of annexin V have strongly suggested apoptosis induction, which has been confirmed by G0/G1 cell cycle arrest.

CONCLUSIONS

The data have clearly shown that exposition of human tumor cell lines to Lafoensia pacari stem barks extract leads to apoptosis induction due to cell cycle arrest in G0/G1 phases, supporting its anticancer use.

Protein-rich fraction of Cnidoscolus urens (L.) Arthur leaves: enzymatic characterization and procoagulant and fibrinogenolytic activities

Proteolytic enzymes are important macromolecules in the regulation of biochemical processes in living organisms. Additionally, these versatile biomolecules have numerous applications in the industrial segment. In this study we have characterized a protein-rich fraction of Cnidoscolus urens (L.) Arthur leaves, rich in proteolytic enzymes, and evaluated its effects on the coagulation cascade. Three protein-rich fractions were obtained from the crude extract of C. urens leaves by precipitation with acetone. Fraction F1.0 showed higher proteolytic activity upon azocasein, and thus, was chosen for subsequent tests. The proteolytic activity of F1.0 on fibrinogen was dose-dependent and time-dependent. The extract demonstrated procoagulant activity on citrated plasma and reduced the APTT, not exerting effects on PT. Despite the fibrin(ogen)olytic activity, F1.0 showed no defibrinogenating activity in vivo. The fraction F1.0 did not express hemorrhagic nor hemolytic activities. The proteolytic activity was inhibited by E-64, EDTA and in the presence of metal ions, and increased when pretreated with reducing agents, suggesting that the observed activity was mostly due to cysteine proteases. Several bands with proteolytic activity were detected by zymography with gelatin, albumin and fibrinogen. The optimal enzymatic activity was observed in temperature of 60 °C and pH 5.0, demonstrating the presence of acidic proteases. In conclusion, these results could provide basis for the pharmacological application of C. urens proteases as a new source of bioactive molecules to treat bleeding and thrombotic disorders.

Identification of Phenolic Compounds and Evaluation of Antioxidant and Antimicrobial Properties of Euphorbia Tirucalli L

Bioactive compounds extracted from natural sources can benefit human health. The aim of this work was to determine total phenolic content and antioxidant activity in extracts of Euphorbia tirucalli L. followed by identification and quantification of the phenolic compounds, as well as their antibacterial activities. Antioxidant activities were determined by DPPH and ABTS^•+ assay. Identification of phenolic compounds was performed using high-performance liquid chromatography (HPLC), and antimicrobial activities were verified by agar dilution methods and MIC values. Total phenolic content ranged from 7.73 to 30.54 mg/100 g gallic acid equivalent. Extracts from dry plants showed higher antioxidant activities than those from fresh ones. The DPPH EC₅₀ values were approximately 12.15 μg/mL and 16.59 μg/mL, respectively. Antioxidant activity measured by the ABTS method yielded values higher than 718.99 μM trolox/g for dry plants, while by the Rancimat^® system yielded protection factors exceeding 1 for all extracts, comparable to synthetic BHT. Ferulic acid was the principal phenolic compound identified and quantified through HPLC-UV in all extracts. The extracts proved effective inhibitory potential for Staphylococcus epidermidis and Staphylococcus aureus. These results showed that extracts of Euphorbia tirucalli L. have excellent antioxidant capacity and moderate antimicrobial activity. These can be attributed to the high concentration of ferulic acid.

Biologically based therapies are commonly self-prescribed by Brazilian women for the treatment of advanced breast cancer or its symptoms

PURPOSE

Breast cancer (BC) might be associated with loss of function in affected patients, with a direct impact on their quality of life (QOL). Many women with metastatic BC seek relief of symptoms, including the use of complementary and alternative medicine (CAM) to cure cancer. The present study aimed to identify the pattern of CAM used by patients with metastatic BC and to assess the correlation between CAM use and scores on anxiety, depression, and QOL scales.

METHODS

A total of 126 women with metastatic BC were interviewed using four instruments: (1) a questionnaire containing socioeconomic, clinical, and demographic data and CAM use; (2) European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ)-C30; (3) EORTC QLQ-BR23; and (4) the Hospital Anxiety and Depression Scale.

RESULTS

Fifty percent of the participants reported the use of at least one CAM modality. Biologically based practices were the most frequently used to treat BC and/or its symptoms, the most commonly discussed with the oncologists, and one of the CAM categories in which more patients reported a desire to learn more about. The overall use of CAM was not correlated with the scores on the anxiety, depression, and QOL scales. However, analysis of the association of the QOL scores with specific CAM modalities revealed some potential associations (especially for food supplements, art therapy, psychotherapy, and prayer).

CONCLUSIONS

Women with metastatic BC frequently make use of CAM to treat the cancer and/or its symptoms. Biologically based practices seem to be particularly important in Brazil. An association between specific CAM modalities and some QOL domains was suggested, but it needs further confirmation.

Euphol arrests breast cancer cells at the G1 phase through the modulation of cyclin D1, p21 and p27 expression

Euphorbia tirucalli is a long‑established treatment for a wide variety of cancers. However, the mechanism of its anticancer effect is yet to be elucidated. In the present study, we examined the anticancer effect of euphol, a tetracyclic triterpene alcohol isolated from the sap of Euphorbia tirucalli, in T47D human breast cancer cells. Following the treatment of cells with different doses of euphol for 24, 48 and 72 h, the cell proliferation, cell cycle, and mRNA and protein levels of cell cycle regulatory molecules were analyzed, respectively. Treatment of the cells with euphol resulted in decreased cell viability, which was accompanied by an accumulation of cells in the G1 phase. Further studies demonstrated that euphol treatment downregulated cyclin D1 expression and the hypophosphorylation of Rb. Furthermore, this effect was correlated with the downregulation of cyclin‑dependent kinase 2 (CDK2) expression and the upregulation of the CDK inhibitors p21 and p27. Reduced expression levels of cyclin A and B1 were also observed, corresponding to the decreased distribution of cells in the S and G2/M phases, respectively. These findings indicated that euphol is an active agent in Euphorbia tirucalli that exerts anticancer activity by arresting the cell cycle of cancer cells.

Seasonal variability of Chelidonium majus L. secondary metabolites content and antioxidant activity

The aim of this study is to investigate the total phenolic content, concentration of flavonoids and antioxidant activity in extracts of the plant Chelidonium majus L. during different phenological stages (stage of rosette, the initial flowering stage, the stage of fully formed flowers and stage of fruits formation). Five different extracts of the whole plant, for each phase, were obtained by extraction with water, methanol, acetone, ethyl acetate and petroleum ether. The concentration of total phenolic content was determined using the Folin-Ciocalteu´s reagent and obtained values were the highest in the rosette stage (60.96 mg GA/g). The concentration of flavonoids was the highest in the initial stage of flowering (291.58 mg RU/g). The antioxidant activity was determined in vitro using DPPH reagent. The highest antioxidant activity was expressed in the rosette stage (50.72 mg/ml). Based on the obtained results it can be concluded that the concentrations of secondary metabolites in Ch. majus depend on the phenological stage of the plant.

Toxicologic assessment of a commercial decolorized whole leaf aloe vera juice, lily of the desert filtered whole leaf juice with aloesorb

Aloe vera, a common ingredient in cosmetics, is increasingly being consumed as a beverage supplement. Although consumer interest in aloe likely stems from its association with several health benefits, a concern has also been raised by a National Toxicology Program Report that a nondecolorized whole leaf aloe vera extract taken internally by rats was associated with intestinal mucosal hyperplasia and ultimately malignancy. We tested a decolorized whole leaf (DCWL) aloe vera, treated with activated charcoal to remove the latex portion of the plant, for genotoxicity in bacteria, acute/subacute toxicity in B6C3F1 mice, and subchronic toxicity in F344 rats. We found this DCWL aloe vera juice to be nongenotoxic in histidine reversion and DNA repair assays. Following acute administration, mice exhibited no adverse signs at 3- or 14-day evaluation periods. When fed to male and female F344 rats over 13 weeks, DCWL aloe led to no toxicity as assessed by behavior, stools, weight gain, feed consumption, organ weights, and hematologic or clinical chemistry profiles. These rats had intestinal mucosal morphologies—examined grossly and microscopically—that were similar to controls. Our studies show that oral administration of this DCWL aloe juice has a different toxicology profile than that of the untreated aloe juice at exposures up to 13 weeks.

Anacardic acid (6-pentadecylsalicylic acid) induces apoptosis of prostate cancer cells through inhibition of androgen receptor and activation of p53 signaling

Anacardic acid (AA) is a mixture of 2-hydroxy-6-alkylbenzoic acid homologs. It is widely regarded as a non-specific histone acetyltransferase inhibitor of p300. The effects and the mechanisms of AA in LNCaP cells (prostate cancer cells) remain unknown. To investigate the effect of AA on LNCaP cells, we had carried out several experiments and found that AA inhibits LNCaP cell proliferation, induces G1/S cell cycle arrest and apoptosis of LNCaP cell. The mechanisms via which AA acts on LNCaP cells may be due to the following aspects. First, AA can regulate p300 transcription and protein level except for its mechanisms regulating function of p300 through post-translational modification in LNCaP cells. Second, AA can activate p53 through increasing the phosphorylation of p53 on Ser15 in LNCaP cells. AA can selectively activate p21 (target genes of p53). Third, AA can down-regulates androgen receptor (AR) through supressing p300. Our study suggests that AA has multiple anti-tumor activities in LNCaP cells and warrants further investigation.

An in vitro and in vivo toxicologic evaluation of a stabilized aloe vera gel supplement drink in mice

Aloe vera gel is increasingly consumed as a beverage dietary supplement. The purpose of this study was to determine potential toxicity of a stabilized aloe vera gel derived from the inner gel fillet and marketed as a drink. The gel juice was assessed through assays of genotoxicity in vivo and acute and subchronic toxicity in B6C3F1 mice. Aloe vera did not increase the SOS DNA repair response in Escherichia coli and at 1× and 0.25× it did not increase mutagenesis of Salmonella TA100 resulting in histidine biosynthesis. At 3 and 14days following acute exposure, male and female mice gavaged with the stabilized aloe gel had daily appearances, total body weight gain, selected organ weights, necropsy and hematology tests similar to control mice gavaged with water. After a 13-week aloe gel feed study, male and female mice evaluated by the same criteria as the acute study plus feed consumption and serum chemistry tests were found to be equivalent to control groups. These data indicate that a commercial stabilized aloe gel consumed as a beverage was not genotoxic or toxic in vivo. These results contrast with those obtained using preparations containing aloe latex phenolic compounds such as anthraquinones.

Genotoxic effects of Tabebuia impetiginosa (Mart. Ex DC.) Standl. (Lamiales, Bignoniaceae) extract in Wistar rats

Tabebuia sp. is native to tropical rain forests throughout Central and South America. Although the biological and pharmacological effects of bark extracts have been intensely studied, little is known on the extract obtained from the flower. Herein, the genotoxic potential of a flower extract from T. impetiginosa ("ipê roxo") on the blood and liver cells of Wistar rats was evaluated. Experimental procedures involved only male animals. Graduated concentrations of the extract, viz., 100, 300 and 500 mg kg(-1) of body weight, were gavage-administered and 24 h latter cells were collected and processed for analysis. With the exception of the 100 mg kg(-1) dose, a significant increase in DNA damage was noted, when compared with a negative control group. Although the genotoxic potential of this extract was higher in liver cells, the response in both tissues was related to dose-dependency. Even though DNA damage can be corrected before conversion into mutations, further study is recommended to arrive at a better understanding of incurred biological effects.

Activation of human neutrophils by the anti-inflammatory mediator Esenbeckia leiocarpa leads to atypical apoptosis

Despite the fact that Esenbeckia leiocarpa, a Brazilian plant, possesses potential anti-inflammatory properties, its effect in neutrophils, key players in inflammation, has never been investigated. In this study, a crude hydroalcoholic extract (CHE) was used to evaluate the potential toxic or agonistic effect of E. leiocarpa in human neutrophils. At a noncytotoxic concentration of 500 μg/mL, CHE increased actin polymerization and cell signaling events, especially p38 MAPK. Its modulatory activity on neutrophil cell apoptosis was investigated by cytology and by flow cytometry and, although CHE increased the apoptotic rate (by cytology) and increased annexin-V binding, it did not, unexpectedly, increase CD16 shedding. CHE increased the degradation of the cytoskeletal proteins gelsolin and paxillin but, surprisingly, not of vimentin. The proapoptotic activity of CHE was reversed by a pan-caspase inhibitor but not by a p38 inhibitor. We conclude that CHE is a novel human neutrophil agonist that induces apoptosis by a caspase-dependent and p38-independent mechanism in an atypical fashion based on its lack of effect on CD16 shedding and vimentin degradation. Since the resolution of inflammation occurs by elimination of apoptotic neutrophils, the ability of CHE to induce neutrophil apoptosis correlates well with its anti-inflammatory properties, as previously reported.