Study of the antiproliferative potential of seed extracts from Northeastern Brazilian plants

Natural product inspired leads in the discovery of anticancer agents: an update

Natural products have emerged as major leads for the discovery and development of new anti-cancer drugs. The plant-derived anti-cancer drugs account for approximately 60% and the quest for new anti-cancer agents is in progress. Anti-cancer leads have been isolated from plants, animals, marine organisms, and microorganisms from time immemorial. The process of semisynthetic modifications of the parent lead has led to the generation of new anti-cancer agents with improved therapeutic efficacy and minimal side effects. The various chemo-informatics tools, bioinformatics, high-throughput screening, and combinatorial synthesis are able to deliver the new natural product lead molecules. Plant-derived anticancer agents in either late preclinical development or early clinical trials include taxol, vincristine, vinblastine, topotecan, irinotecan, etoposide, paclitaxel, and docetaxel. Similarly, anti-cancer agents from microbial sources include dactinomycin, bleomycin, mitomycin C, and doxorubicin. In this review, we highlighted the importance of natural products leads in the discovery and development of novel anti-cancer agents. The semisynthetic modifications of the parent lead to the new anti-cancer agent are also presented. Further, the leads in the preclinical settings with the potential to become effective anticancer agents are also reviewed.Communicated by Ramaswamy H. Sarma.

Antimitotic and toxicogenetic action of Stevia urticifolia aerial parts on proliferating vegetal and mammalian cells: in vitro and in vivo traditional and replacement methods

Stevia urticifolia Thunb. is an underexploited herb possessing bioactive flavonoids, saponins, and terpenoids. The aim of this study was to examine the antiproliferative and toxicogenetic properties of the ethyl acetate extract from Stevia urticifolia aerial parts (EtAcSur) upon Artemia salina, erythrocytes, Allium cepa and sarcoma 180 cells and fibroblasts, as well as in vivo studies on mice to determine systemic, macroscopic, and behavioral alterations and bone marrow chromosomal damage. The assessment using A. salina larvae and mouse blood cells revealed LC₅₀ and EC₅₀ values of 68.9 and 113.6 µg/ml, respectively. Root growth and mitosis were inhibited by EtAcSur, and chromosomal aberrations were detected only at 100 μg/ml. EtAcSur exhibited potent concentration-dependent viability reduction of S180 and L-929 cells and antioxidant capacity employing ABTS^• and DPPH^•. No previous in vivo studies were performed before with the EtAcSur. Signals of acute toxicity were not observed at 300 mg/kg. Physiological and toxicological investigations at 25 and 50 mg/mg/day i.p. for 8 days did not markedly change body or organ relative weights, nor patterns of spontaneous locomotor and exploratory activities. In contrast, clastogenic effects on bone marrow were found at 50 mg/mg/day. EtAcSur was found to (1) produce toxicity in microcrustaceans, (2) capacity as free radical scavenger, (3) antimitotic, cytotoxic and clastogenic activties upon vegetal and mammalian cells, and (4) lethality on both tumor and normal murine cells indistinctly. In vivo damage systemic effects were not remarkable and clinical signals of toxicity were not observed, suggesting the significant pharmacological potential of S. urticifolia for the development of antineoplastic agents.Abbreviations: ABTS: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); DMSO: dimethylsulfoxide; DPPH: 1,1-diphenyl-2-picrylhydrazyl; EC₅₀: effective concentration 50%; EtAcSur: ethyl acetate extract from Stevia urticifolia aerial parts; Hb, hemoglobin; IC₅₀: inhibitory concentration 50%; LC₅₀,: lethal concentration 50%; MI: mitotic index; RBC, red blood cells; Trolox: 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid.

Profile of Myracrodruon urundeuva Volatile Compounds Ease of Extraction and Biodegradability and In Silico Evaluation of Their Interactions with COX-1 and iNOS

Myracrodruon urundeuva Fr. Allem. (Anacardiaceae) is a tree popularly known as the "aroeira-do-sertão", native to the caatinga and cerrado biomes, with a natural dispersion ranging from the Northeast, Midwest, to Southeast Brazil. Its wood is highly valued and overexploited, due to its characteristics such as durability and resistance to decaying. The diversity of chemical constituents in aroeira seed has shown biological properties against microorganisms and helminths. As such, this work aimed to identify the profile of volatile compounds present in aroeira seeds. Headspace solid phase microextraction was employed (HS-SPME) using semi-polar polydimethylsiloxane-divinylbenzene fiber (PDMS/DVB) for the extraction of VOCs. 22 volatile organic compounds were identified: nine monoterpenes and eight sesquiterpenes, in addition to six compounds belonging to different chemical classes such as fatty acids, terpenoids, salicylates and others. Those that stood out were p-mentha-1,4, 4(8)-diene, 3-carene (found in all samples), caryophyllene and cis-geranylacetone. A virtual docking analysis suggested that around 65% of the VOCs molar content from the aroeiras seeds present moderate a strong ability to bind to cyclooxygenase I (COX-I) active site, oxide nitric synthase (iNOS) active site (iNOSas) or to iNOS cofactor site (iNOScs), corroborating an anti-inflamatory potential. A pharmacophoric descriptor analysis allowed to infer the more determinant characteristics of these compounds' conferring affinity to each site. Taken together, our results illustrate the high applicability for the integrated use of SPME, in silico virtual screening and chemoinformatics tools at the profiling of the biotechnological and pharmaceutical potential of natural sources.

Chemotherapeutic and Safety Profile of a Fraction from Mimosa caesalpiniifolia Stem Bark

Mimosa caesalpiniifolia (Fabaceae) is used by Brazilian people to treat hypertension, bronchitis, and skin infections. Herein, we evaluated the antiproliferative action of the dichloromethane fraction from M. caesalpiniifolia (DFMC) stem bark on murine tumor cells and the in vivo toxicogenetic profile. Initially, the cytotoxic activity of DFMC on primary cultures of Sarcoma 180 (S180) cells by Alamar Blue, trypan, and cytokinesis block micronucleus (CBMN) assays was assessed after 72 h of exposure, followed by the treatment of S180-bearing Swiss mice for 7 days, physiological investigations, and DNA/chromosomal damage. DFMC and betulinic acid revealed similar in vitro antiproliferative action on S180 cells and induced a reduction in viable cells, induced a reduction in viable cells and caused the emergence of bridges, buds, and morphological features of apoptosis and necrosis. S180-transplanted mice treated with DFMC (50 and 100 mg/kg/day), a betulinic acid-rich dichloromethane, showed for the first time in vivo tumor growth reduction (64.8 and 80.0%) and poorer peri- and intratumor quantities of vessels. Such antiproliferative action was associated with detectible side effects (loss of weight, reduction of spleen, lymphocytopenia, and neutrophilia and increasing of GOT and micronucleus in bone marrow), but preclinical general anticancer properties of the DFMC were not threatened by toxicological effects, and these biomedical discoveries validate the ethnopharmacological reputation of Mimosa species as emerging phytotherapy sources of lead molecules.

Toxicological, chemopreventive, and cytotoxic potentialities of rare vegetal species and supporting findings for the Brazilian Unified Health System (SUS)

Caatinga flora which are found in a poor Brazilian region contain a substantial number of endemic taxa with biomedical and social importance for regional communities. This study examined the antioxidant and cytotoxic potential of 35 samples (extracts/fractions) from 12 Caatinga species and determined the antiproliferative and genotoxic action of dichloromethane fraction from Mimosa caesalpiniifolia stem bark (DC-Mca) on human and vegetal cells. Samples were assessed for chemopreventive ability, toxic effects on Artemia salina shrimp as well as cytotoxicity on tumor cell lines and erythrocytes. DC-Mca was also tested with respect to antiproliferative and genotoxic effects upon normal leukocytes and meristematic cells from A. cepa roots. Some extracts reduced free radical levels >95% and 7 samples exhibited a lethal concentration (LC) ₅₀ < 100 µg/ml upon Artemia salina larvae. Eight samples displayed in vitro antitumor effects and three produced hemolysis. Data also demonstrated the pharmacological significance of bioactive extracts from Brazilian semi-arid region. There was no significant relationship between antioxidant, toxic, and antiproliferative activities, and that these properties were dependent upon the extractant. DC-Mca contained betulinic acid as main compound (approximately 70%), which showed higher (1) cytotoxic activity on cancer cell lines and dividing leukocytes, (2) reduced mitotic index of Allium cepa roots, and (3) induced cell cycle arrest and chromosomal bridges, thereby providing native promising sources for phytotherapy development.

ABBREVIATIONS

ABTS: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); AcOH: ethyl acetate; ANOVA: analysis of variance; SUS: Brazilian Unified Health System; DC-Mca: dichloromethane fraction from Mimosa caesalpiniifolia stem bark; DMSO: dimethylsulfoxide; DPPH: 1,1-diphenyl-2-picrylhydrazyl; EC₅₀: effective concentration 50%; EtOAc: ethyl acetate; FDA: Food and Drug Administration; GC-Qms: gas chromatograph quadrupole mass spectrometer; GI: genotoxic index; HCT-116: colon carcinoma line; HL-60: promyelocytic leukemia line; HPLC: high-performance liquid chromatography; HRAPCIMS: high resolution atmospheric pressure chemical ionization mass spectrum; IC₅₀: inhibitory concentration 50%; LC₅₀: lethal concentration 50%; MeOH = methyl alcohol; MI: mitotic index; MTT: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide; MutI: mutagenic index; OVCAR-8 = ovarian carcinoma line; PBMC: peripheral blood mononuclear cells; RPMI-1640: Roswell Park Memorial Institute medium; SF-295: glioblastoma line; TEAC: trolox equivalent antioxidant capacity; TLC: thin-layer chromatography; Trolox: 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid.

Triplaris gardneriana seeds extract exhibits in vitro anti-inflammatory properties in human neutrophils after oxidative treatment

ETHNOPHARMACOLOGICAL RELEVANCE

Triplaris gardneriana Wedd. (Polygonaceae family) is a plant species from Brazilian semiarid region which is used in local traditional medicine for the treatment of inflammatory conditions such as hemorrhoids.

AIM OF THE STUDY

In this study, the in vitro anti-inflammatory activity of different concentrations of ethanolic extract from T. gardneriana seeds (EETg) was performed in order to contribute to the knowledge about etnomedicinal use of this plant species.

MATERIALS AND METHODS

The anti-inflammatory properties were evaluated through different approaches, such as in vitro protein anti-denaturation test, scavenging of reactive oxygen species (ROS) and myeloperoxidase (MPO) inhibition in human neutrophils activated by phorbol-12-myristate-13-acetate (PMA). Besides that, molecular docking was performed to provide new insights about the interaction between the major phenolic components in the plant extract and MPO.

RESULTS

EETg was characterized showing a total phenol content of 153.5 ± 6.3 μg gallic acid equivalent/mg extract, ability to remove hydrogen peroxide (H₂O₂) in a concentration-dependent manner and had a spectroscopic profile which suggests the presence of hydroxyl groups. EETg was able to prevent protein denaturation ranging from 40.17 to 75.09%. The extract, at 10 and 20 μg/mL, was able to modulate neutrophils pro-inflammatory functions, such as degranulation and burst respiratory. In both assays, the EETg had anti-inflammatory effect comparable to nonsteroidal anti-inflammatory drugs. Among the main phenolic compounds of EETg, quercitrin, quercetin and catechin showed the highest binding affinity in silico to MPO.

CONCLUSION

This study demonstrated, for the first time, that the anti-inflammatory effect of T. gardneriana seeds occurs due to its modulatory effect on human neutrophil degranulation and free-radical scavenging activity.

Ascorbic acid and retinol palmitate modulatory effect on omeprazole-induced oxidative damage, and the cytogenetic changes in S. cerevisiae and S180 cells

Omeprazole (OM), a prototype proton pump inhibitor, oxidizes thiol groups and induces DNA damage. The aim of this study was to evaluate the oxidative effects of omeprazole and its interactions with ascorbic acid (AA, 50 μM) and retinol palmitate (RP) in proficient and deficient Saccharomyces cerevisiae strains, as well as levels of cytogenetic damage in Sarcoma 180 (S180) cells. Omeprazole was tested at concentrations of 10, 20 and 40 μg/mL, whereas H₂O₂ (10 mM), cyclophosphamide (20 mg/mL), and saline (0.9% NaCl solution) were employed as stressor, positive control, and negative control, respectively. Results revealed that omeprazole concentration-dependently induces oxidative effects in S. cerevisiae strains. However, omeprazole co-treated with ascorbic acid (50 μM) and retinol palmitate (100 IU) significantly modulated the oxidative damage inflected on the S. cerevisiae strains. Furthermore, omeprazole did not produce micronucleus formation and chromosomal bridges in S180 cells, but induced shoots. Significant increase in karyolysis and karyorrhexis were also observed with the omeprazole treated groups, which was modulated by co-treatment with ascorbic acid and retinol palmitate. Taken all together, it is suggested that ascorbic acid and retinol palmitate can substantially modulate the oxidative damage caused by omeprazole on the S. cerevisiae strains, however, much precaution is recommended with omeprazole and antioxidant co-treatment.

An extract from Myracrodruon urundeuva inhibits matrix mineralization in human osteoblasts

ETHNOPHARMACOLOGICAL RELEVANCE

Phytotherapy based on plant-derived compounds is an alternative medicinal strategy for the relief of symptoms and the curing of diseases. The leaves of Myracrodruon urundeuva a medicinal plant also known as "aroeira", has been used in traditional medicine as healing, antiulcer and anti-inflammatory to treat skeletal diseases in Brazil, but its role in bone cell toxicity, as well as in bone formation, remains to be established.

AIM OF THE STUDY

We sought to determine the in vitro osteogenic effects of a hydroalcoholic M. urundeuva leaves extract in primary human osteoblasts.

MATERIALS AND METHODS

Cell viability, reactive oxygen species (ROS) production, alkaline phosphatase (ALP) activity and matrix mineralization were evaluated by MTT assay, DCFH-DA probe, colorimetric-based enzymatic assay and Alizarin Red-staining, respectively. Besides, the matrix metalloproteinase (MMP)-2 and progressive ankylosis protein homolog (ANKH) gene expression were determined by real-time RT-qPCR and MMP-2 activity by zymography.

RESULTS

Exposure of osteoblasts to M. urundeuva extract significantly decreased viability and increased reactive oxygen species (ROS) production, regardless of the extract concentration. The M. urundeuva extract at 10 μg/mL also downregulated matrix metalloproteinase (MMP)-2, while upregulating progressive ankylosis protein homolog (ANKH) gene expression. By contrast, the MMP-2 activity was unchanged. The M. urundeuva extract at 10 μg/mL also reduced alkaline phosphatase (ALP) activity and mineralization.

CONCLUSIONS

Overall, our findings suggest that the inhibition of osteogenic differentiation and matrix mineralization promoted by M. urundeuva may be due more to an increase in oxidative stress than to the modulation of MMP-2 and ANKH expression.

Medicinal plants commonly used against cancer in traditional medicine formulae in Sri Lanka

Cancer is a global burden. In low- and middle-income countries around 70% of deaths are due to cancer. For a number of years natural products have been a good source of agents for combatting cancer and plants have played a huge role in anti-cancer product development. For many centuries, indigenous cultures around the world have used traditional herbal medicine to treat a myriad of diseases including cancer. In Sri Lanka, a number of plants have been reported to have anti-cancer properties and some of the commonly used plants are described in this review with an account of their compounds and modes of action. Only a small number of the plants in Sri Lanka have been tested for their bioactivity and more research is required to determine their medicinal activity with the aim of developing novel drugs to fight this disease.

Chemical composition and evaluation of the antibacterial and Cytotoxic activities of the essential oil from the leaves of Myracrodruon urundeuva

BACKGROUND

This study evaluated the in vitro activity of essential oil extracted from the leaves of Myracrodruon urundeuva.

METHODS

The oil was obtained by hydro-distillation and characterized by Gas Chromatography coupled to Mass Spectrometry (GC-MS) and Gas Chromatography with Flame Ionization Detector (GC-FID). The antibacterial activity was evaluated by the broth microdilution technique and the MIF was determined by using growth indicator CTT (2,3,5-triphenyl-tetrazolium) and CBM in BHI agar. The oil's cytotoxicity was evaluated in HeLa, HEK-293, and Vero E6 cells using MTT, 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium.

RESULTS

The oil showed chemical markers, including α-pinene (87.85%), trans-caryophyllene (1.57%), limonene (1.49%) and β -pinene (1.42%), and activity against all strains: Staphylococcus aureus (MIC = MBC = 0.22 mg/mL), Staphylococcus epidermidis (MIC = 0.11 mg/mL and MBC = 0.22 mg/mL), Escherichia coli (MIC = 0.88 mg/mL and MBC = 1.75 mg/mL), Pseudomonas aeruginosa (MIC = MBC = 7 mg/mL) and Salmonella Enteritidis (MIC = MBC = 0.44 mg/mL). In vitro cytotoxicity tests showed that the oil is not toxic and has slight antitumor activity.

CONCLUSIONS

We conclude that the M. urundeuva oil results are promising, with prospects of being pharmacologically viable.

Libidibia ferrea presents antiproliferative, apoptotic and antioxidant effects in a colorectal cancer cell line

Colorectal cancer is noted for being one of the most frequent of tumors, with expressive morbidity and mortality rates. In new drug discovery, plants stand out as a source capable of yielding safe and high-efficiency products. Well known in Brazilian popular medicine, Libidibia ferrea (Mart. Ex Tul.) L.P. Queiroz var. ferrea (better known as "ironwood" or "jucá"), has been used to treat a wide spectrum of conditions and to prevent cancer. Using methodologies that involved flow cytometry, spectrophotometry and RT-qPCR assays, crude extracts of the fruits of L. ferrea (20T, 40T, 60T and 80T) were evaluated at 24h and/or 48h for: their ability to inhibit cell proliferation; induce apoptosis through Bcl-2, caspase-3 and Apaf-1; their antioxidant activity and effects on important targets related to cell proliferation (EGFR and AKT) in the HT-29 human colorectal cancer lineage. The results revealed high antiproliferative potential as compared to the controls, induction of apoptosis through the intrinsic pathway, and probable tumor inhibition activity under the mediation of important targets in tumorigenesis. In addition, L. ferrea revealed antioxidant, lipid peroxidation and chemoprotective effects in healthy cells. Thus, L. ferrea derivatives have important anticancer effects, and may be considered promising candidate for colorectal cancer therapy.

Are salty liquid food flavorings in vitro antitumor substances?

The objective of this study was to evaluate the antiproliferative, cytotoxic and genotoxic potential of salty liquid synthetic flavorings of Butter, Cheddar Cheese and Onion. The antiproliferative potential (2.9-1500 µg/mL) was assessed by MTT assay after 72h using the human tumor lines SF-295 (glioblastoma), OVCAR-8 (ovarian), HCT-116 (colon) and HL-60 (promyelocytic leukemia) and primary cultures of murine Sarcoma 180 (S180) and peripheral blood mononuclear cells (PBMC). Allium cepa bulbs were exposed to growing respective doses (1 mL and 2 mL). Only Butter and Cheddar flavorings revealed cytotoxic activity on cancer cells, with IC50 values ranging from 125.4 µg/mL (Cheddar - HCT-116) to 402.6 µg/mL (Butter - OVCAR-8). Butter flavoring was the most cytotoxic on PBMC (136.3 µg/mL) and increased cell division rate in relation to the mitotic index but did not cause cellular aberrations. Onion and Cheddar flavorings reduced the mitotic index after 24h and 48h exposure, but only Onion flavoring resulted in cellular aberrations and mitotic spindle abnormalities, such as anaphase and telophase bridges, micronucleated cells, conchicine-metaphases and amplifications. So, Butter, Onion and/or Cheddar flavorings caused significant changes in the division of meristematic cells of A. cepa and presented cytotoxic action even on decontrolled proliferating human tumor cells.

Antiplasmodial and Cytotoxic Activities of Toad Venoms from Southern Amazon, Brazil

The drug-resistance of malaria parasites is the main problem in the disease control. The huge Brazilian biodiversity promotes the search for new compounds, where the animal kingdom is proving to be a promising source of bioactive compounds. The main objective of this study was to evaluate the antiplasmodial and cytotoxic activity of the compounds obtained from the toad venoms of Brazilian Amazon. Toad venoms were collected from the secretion of Rhinella marina and Rhaebo guttatus in Mato Grosso State, Brazil. The powder was extracted at room temperature, yielding 2 extracts (RG and RM) and a substance ('1') identified as a bufadienolide, named telocinobufagin. Growth inhibition, intraerythrocytic development, and parasite morphology were evaluated in culture by microscopic observations of Giemsa-stained thin blood films. Cytotoxicity was determined against HepG2 and BGM cells by MTT and neutral red assays. The 2 extracts and the pure substance ('1') tested were active against chloroquine-resistant Plasmodium falciparum strain, demonstrating lower IC50 values. In cytotoxic tests, the 2 extracts and substance '1' showed pronounced lethal effects on chloroquine-resistant P. faciparum strain and low cytotoxic effect, highlighting toad parotoid gland secretions as a promising source of novel lead antiplasmodial compounds.

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.

Preclinical anticancer effectiveness of a fraction from Casearia sylvestris and its component Casearin X: in vivo and ex vivo methods and microscopy examinations

ETHNOPHARMACOLOGICAL RELEVANCE

Casearia sylvestris (Salicaceae) is found in South America and presents antiulcerogenic, cytotoxic, antimicrobial, anti-inflammatory and antihypertensive activities.

AIM OF THE STUDY

To assess the in vivo and ex vivo antitumor action of a fraction with casearins (FC) and its main component - Casearin X-isolated from C. sylvestris leaves.

MATERIALS AND METHODS

Firstly, Sarcoma 180 bearing Swiss mice were treated with FC and Cas X for 7 days. Secondly, BALB/c nude animals received hollow fibers with colon carcinoma (HCT-116) or glioblastoma (SF-295) cells and were treated with FC for 4 days. On 5th day, proliferation was determined by MTT assay.

RESULTS

FC 10 and 25mg/kg/day i.p. and 50mg/kg/day oral and Cas X 25mg/kg/day i.p. and 50mg/kg/day oral revealed tumor growth inhibition rates of 35.8, 86.2, 53.7, 90.0 and 65.5% and such tumors demonstrated rare mitoses and coagulation necrosis areas. Similarly, FC reduced multiplying of HCT-116 and SF-295 cells when evaluated by the Hollow Fiber Assay (2.5 and 5mg/kg/day i.p. and 25 and 50mg/kg/day oral), with cell growth inhibition rates ranging from 33.3 to 67.4% (p<0.05). Flow cytometry experiments revealed that FC reduced membrane integrity and induced DNA fragmentation and mitochondrial depolarization (p<0.05).

CONCLUSIONS

FC and Cas X were efficient antitumor substances against murine and human cancer cells and caused reversible morphological changes in liver, kidneys and spleens, emphasizing clerodane diterpenes as an emerging class of anticancer molecules.

Evaluation of anticancer properties of a decoction containing Adenanthera pavonina L. and Thespesia populnea L

Background

A decoction composed of Adenanthera pavonina L. and Thespesia populnea L. is currently being used in the treatment of cancer patients.

Methods

Lactate Dehydrogenase (LDH) release, (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) MTT, and Sulforhodamine B (SRB) assays were carried out to study cytotoxicity and anti-proliferative activity against the HEp-2 cells, 24 h post-treatment with the decoction.

Results

The mean (± SD) values of EC₅₀ were 195.50 (±40.68), 120.02 (±29.82) and 77.06 (±8.80) μg/ml for LDH, MTT, and SRB assays respectively. These results strongly correlate the morphological changes observed in cells treated with the decoction. Induction of apoptosis was visualized by fluorescence microscopy stained with ethidium bromide/acridine orange dye mix. In addition, brine shrimp lethality assay showed an EC₅₀ value at a higher concentration (1.96 mg/mL).

Conclusions

These results suggest that the decoction prepared with Adenanthera pavonina L. and Thespesia populnea L. exhibits anti-proliferative activity and induces apoptosis on the HEp-2 cancer cells but no toxicity against Artemia salina.

Evaluation of the Acute Toxicity, Cytotoxicity, and Genotoxicity of Chresta martii (Asteraceae)

Chresta martii (Asteraceae), found in the Xingó region, northeastern Brazil, is used in the treatment of gastrointestinal (GIT) and liver disorders and malaria. However, there are few studies regarding efficacy and safety of use for this species. Thus, the objective of this study was to determine in vivo acute toxicity and in vitro cytotoxicity of organic extracts of C. martii as well as in vivo genotoxicity of its semipurified fraction. Dried aerial parts of C. martii were extracted using three organic solvents (cyclohexane [ECCm], ethyl acetate [EACm], and ethanol [EECm]), and these extracts were examined for acute toxicity (50-2000 mg/kg ip or po) and cytotoxicity (50 μg/ml) in carcinogenic human cell lines (HL-60, NCIH-292, and MCF-7). The EACm, which showed evidence of toxicity (in vivo and in vitro), was fractionated on a silica column, yielding four fractions (F1-F4). The F1 was utilized for genotoxicity (50 mg/kg ip), by in vivo micronucleus (MN) assay. ECCm showed no indication of acute toxicity or occurrence of death, while the LD50 estimated for the extracts (EACm and EECm) was 500 mg/kg po and 200 mg/kg ip. The EACm (50 μg/ml) inhibited growth of tumor cells HL-60 (96.54%), NCIH-292 (73.43%), and MCF-7 (15%). The F1 fraction induced MN formation in polychromatic erythrocytes of Swiss Webster mice. Organic extracts from C. martii exhibited acute toxicity classified as mild to moderate, in addition to cytotoxicity (in vitro), while the F1 semipurified fraction induced genotoxicity (in vivo).

Biomedical properties and potentiality of Lippia microphylla Cham. and its essential oils

Lippia microphylla Cham. (Verbenaceae) is an endemic underexploited Brazilian vegetal. This work reviewed the biological potentialities of Lippia microphylla, emphasizing the properties of essential oils (EOs) and analyzed scientific indicators about genus Lippia and L. microphylla. Databases from 1948 to the present were searched and a software (vantage point 7.1) associated with Derwent Innovation Index was used to identify the indicators of the genus Lippia, and biological activities and compounds in the L. macrophylla species. Ethnopharmacological records report use of L. microphylla leaves to treat gastrointestinal disorders, influenza, bronchitis, cough, nasal congestion, and sinusitis during vaporization, whose aromatic volatile oils are rich in monoterpenes, especially cineole, terpineol, and thymol. Other EOs have larvicidal activity on Aedes aegypti larvae, and antifungal, antibacterial and cytotoxic and antitumor action on human and murine cancer cells. Brazil is the country with more articles about Lippia species, but it deposited only 9 patents since 1993. Most of the publications about L. microphylla are concentrated in food and chemical sciences. This bioprospection helps to choice areas of interest for capital investment and to give support for Brazilian Institutions to establish cooperation and improve technological impact at the point of view of creation and innovation.

Cytotoxic and toxicological effects of phthalimide derivatives on tumor and normal murine cells

Eleven phthalimide derivatives were evaluated with regards to their antiproliferative activity on tumor and normal cells and possible toxic effects. Cytotoxic analyses were performed against murine tumors (Sarcoma 180 and B-16/F-10 cells) and peripheral blood mononuclear cells (PBMC) using MTT and Alamar Blue assays. Following, the investigation of cytotoxicity was executed by flow cytometry analysis and antitumoral and toxicological potential by in vivo techniques. The molecules 3b, 3c, 4 and 5 revealed in vitro cytotoxicity against Sarcoma 180, B-16/F-10 and PBMC. Since compound 4 was the most effective derivative, it was chosen to detail the mechanism of action after 24, 48 and 72 h exposure (22.5 and 45 µM). Sarcoma 180 cells treated with compound 4 showed membrane disruption, DNA fragmentation and mitochondrial depolarization in a time- and dose-dependent way. Compounds 3c, 4 and 5 (50 mg/kg/day) did not inhibit in vivotumor growth. Compound 4-treated animals exhibited an increase in total leukocytes, lymphocytes and spleen relative weight, a decreasing in neutrophils and hyperplasia of spleen white pulp. Treated animals presented reversible histological changes. Molecule 4 had in vitro antiproliferative action possibly triggered by apoptosis, reversible toxic effects on kidneys, spleen and livers and exhibited immunostimulant properties that can be explored to attack neoplasic cells.

Antibacterial, antioxidant, and anticholinesterase activities of plant seed extracts from Brazilian semiarid region

The antimicrobial, antioxidant, and anticholinesterase activities of ethanolic seed extracts of twenty-one plant species from Brazilian semiarid region were investigated. The extracts were tested for antimicrobial activity against six bacteria strains and three yeasts. Six extracts presented activity against the Gram (-) organism Salmonella choleraesuis and the Gram (+) organisms Staphylococcus aureus and Bacillus subtilis. The MIC values ranged from 4.96 to 37.32 mg/mL. The Triplaris gardneriana extract presented activity against the three species, with MIC values 18.8, 13.76, and 11.15 mg/mL, respectively. Five extracts presented antioxidant activity, with EC50 values ranging from 69.73 μ g/mL (T. gardneriana) to 487.51 μ g/mL (Licania rigida). For the anticholinesterase activity, eleven extracts were capable of inhibiting the enzyme activity. From those, T. gardneriana, Parkia platycephala and Connarus detersus presented the best activities, with inhibition values of 76.7, 71.5, and 91.9%, respectively. The extracts that presented antimicrobial activity were tested for hemolytic assay against human A, B, and O blood types and rabbit blood. From those, only the Myracrodruon urundeuva extract presented activity (about 20% of hemolysis at the lowest tested concentration, 1.9 µg/mL). Infrared spectroscopy of six representative extracts attested the presence of tannins, polyphenols, and flavonoids, which was confirmed by a qualitative phytochemical assay.

Cytotoxic and bioactive properties of different color tulip flowers and degradation kinetic of tulip flower anthocyanins

This study was conducted to determine the potential use of anthocyanin-based extracts (ABEs) of wasted tulip flowers as food/drug colorants. For this aim, wasted tulip flowers were samples and analyzed for their bioactive properties and cytotoxicity. Total phenolic contents of the extracts of the claret red (126.55 mg of gallic acid equivalent (GAE)/g dry extract) and orange-red (113.76 mg GAE/g dry extract) flowers were the higher than those of the other tulip flowers. Total anthocyanin levels of the violet, orange-red, claret red and pink tulip flower extracts were determined as 265.04, 236.49, 839.08 and 404.45 mg pelargonidin 3-glucoside/kg dry extract, respectively and these levels were higher than those of the other flowers. The extracts were more effective for the inhibition of Listeria monocytogenes, Staphylococcus aureus and Yersinia enterocolitica compared to other tested bacteria. Additionally, the cytotoxic effects of five different tulip flower extracts on human breast adenocarcinoma (MCF-7) cell line were investigated. The results showed that the orange red, pink and violet extracts had no cytotoxic activity against MCF-7 cell lines while yellow and claret red extracts appeared to be toxic for the cells. Overall, the extracts of tulip flowers with different colors possess remarkable bioactive and cytotoxic properties.