Genotoxicity and toxicological evaluations of Brazilian red propolis oral ingestion in a preclinical rodent model.

ETHNOPHARMACOLOGICAL RELEVANCE: Brazilian red propolis is a natural product known due to its medicinal properties. The efficacy of this natural resin has been proved; however, few studies report the safety of its oral use. Some toxic effects of natural products may not be expressed in traditional use, and preclinical studies are necessary to guarantee their safety. Health regulatory agency currently requires these non-clinical studies to develop drugs and herbal medicines, including genotoxic and oral toxicity tests. AIM OF THE STUDY: Accomplish the preclinical toxicity studies of Brazilian red propolis extract (BRP) in rodents, including genotoxicity, acute and sub-chronic toxicities. MATERIAL AND METHODS: Genotoxicity assays followed the erythrocyte micronucleus test protocol in a range of 500-2000 mg/kg BRP oral treatment on male Swiss mice. After an up-and-down procedure, acute oral toxicity (single dose) was performed on female Wistar Hannover rats, reaching a 2000 mg/kg BRP oral gavage concentration. Animals were monitored periodically until 14 days and euthanized for a macroscopic necropsy analysis. The sub-chronic oral toxicity test (90 days) was achieved with 1000 mg/kg of BRP on Wistar Hannover rats (males/females). Animals were monitored to evaluated behavioral and biometrical changes, then were euthanized to perfomed hematological, biochemical, and histopathological analyses. RESULTS: No genotoxic effect of the BRP was detected. The acute toxicity indicated no toxicity of a single oral dose of 2000 mg/kg of BRP. The long-term oral toxicity performed with 1000 mg/kg of BRP altered water and food intake and the biometrics, hematological and biochemical parameters. Biochemical alterations in hepatic and renal parameters were detected only in the males. Despite the detection of biochemical alterations, no histopathological changes were detected in the organs of any group. CONCLUSIONS: BRP, at a higher dose, showed no signs of immediate toxicity. However, the obtained results suggest that the chemical composition and the intake of higher doses deserve special attention regarding possible toxicity.

Toxicological and chemoprevention studies of Dalbergia ecastaphyllum (L.) Taub. stem, the botanical source of Brazilian red propolis.

OBJECTIVES: Dalbergia ecastaphyllum (L.) Taub. is a semi-prostrate species associated with estuaries, mangroves and dunes. This plant species has great ecological and economic importance, especially concerning apiculture pasture and Brazilian red propolis production. In this study, non-clinical toxicological evaluations of the hydroalcoholic extract of D. ecastaphyllum stems (DEHE), the resin production source, were conducted. In addition, the action of DEHE on genomic instability and colon carcinogenesis was investigated. METHODS AND RESULTS: The extract's chemical profile was analysed by HPLC, and medicarpin, vestitol and neovestitol were found as major compounds. DEHE showed an IC50 equivalent to 373.2 µg/ml and LC50 equal 24.4 mg/L, when evaluated using the XTT colorimetric test and the zebrafish acute toxicity assay, respectively. DEHE was neither genotoxic nor cytotoxic at the highest dose, 2000 mg/kg, by peripheral blood micronucleus test. The treatments DEHE (6 and 24 mg/kg) led to the reduction of micronuclei induced by doxorubicin (DXR) in mice. Furthermore, significantly higher serum levels of reduced glutathione were observed in animals treated with DEHE plus DXR, revealing an antioxidant effect. Treatments with DEHE (48 mg/kg) led to a significant reduction in pre-neoplastic lesions induced by the 1,2-dimethylhydrazine (DMH) carcinogen in the rat colon. Immunohistochemical analysis revealed significantly lower levels of expression of COX-2 (86%) and PCNA (83%) in the colon of rats treated with DEHE plus DMH, concerning those treated with the carcinogen. CONCLUSIONS: These results indicate the involvement of anti-inflammatory and antiproliferative pathways in the protective effect of DEHE.

Hexane extracts from fruit of two varieties of Capsicum chinense Jacq.: their volatile constituents and antiacetylcholinesterase, antileishmanial and antiproliferative activities.

This article aims to investigate volatile constituents and antiacetylcholinesterase, antileishmanial and antiproliferative activities of hexane extracts from Capsicum chinense fruit (unripe bode pepper 'HE-UB' and ripe little beak pepper 'HE-RB'). HE-UB and HE-RB were screened by the microplate assay method to determine their antiacetylcholinesterase activity. Both exhibited inhibitory potential, i. e., IC50 = 41.5 and 20.3 µg/mL, respectively. HE-UB (IC50 = 67.19 µg/mL) and HE-RB (IC50 = 38.16 µg/mL) exhibited antileishmanial activity against promastigote forms of Leishmania (Leishmania) amazonensis. In addition, HE-UB and HE-RB demonstrated cytotoxic activity against different human tumor cell lines with IC50 ranging from 325.40 to 425.0 µg/mL. Both GC-FID and GC-MS analyses revealed that the major component in both extracts was E-caryophyllene. In short, HE-RB was more satisfactory than HE-UB in all in vitro activities under evaluation. These findings may be used as initial data for further studies of Capsicum species.

Chemical study of Adenocalymma axillarum crude leaf extract and isolated compounds

Abstract Adenocalymma axillarum (K.Schum.) L.G. Lohmann is a liana belonging to the family Bignoniaceae. In traditional medicine, the genus Adenocalymma is used to treat fever, skin ailments, and body, joint, and facial muscle pains, and it is also applied as cosmetic. Biological assays conducted with the A. axillarum crude leaf ethanol extract have indicated leishmanicidal activity and absence of cytotoxicity. This study aimed to analyze the A. axillarum leaf ethanol crude extract by high-performance liquid chromatography-high-resolution mass spectrometry- diode array detector (HPLC-HRMS-DAD) and to evaluate the leishmanicidal and cytotoxic activities of this crude extract, its fractions, and isolated compounds. HPLC-HRMS-DAD analysis of this extract revealed that it consisted mainly of flavonoids, with nine major compounds. Extract purification yielded 4-hydroxy-N-methylproline, 6-β-hydroxyipolamiide, quercetin-3-O-robinobioside, hyperin, isorhamnetin-3-O-robinobioside, and 3'-O-methylhyperin, which were identified by Nuclear Magnetic Resonance. The isolated compounds were inactive against Leishmania amazonensis promastigotes and human lung fibroblast cells.

Nonclinical Toxicological Studies of Brazilian Red Propolis and Its Primary Botanical Source Dalbergia ecastaphyllum.

Propolis is one of the most widely used products in traditional medicine. One of the most prominent types of Brazilian propolis is the red one, whose primary botanical source is Dalbergia ecastaphyllum (L.) Taub. Despite the potential of Brazilian red propolis for developing new products with pharmacological activity, few studies guarantee safety in its use. The objective of this study was the evaluation of the possible toxic effects of Brazilian red propolis and D. ecastaphyllum, as well as the cytotoxicity assessment of the main compounds of red propolis on tumoral cell lines. Hydroalcoholic extracts of the Brazilian red propolis (BRPE) and D. ecastaphyllum stems (DSE) and leaves (DLE) were prepared and chromatographed for isolation of the major compounds. RP-HPLC-DAD was used to quantify the major compounds in the obtained extracts. The XTT assay was used to evaluate the cytotoxic activity of the extracts in the human fibroblast cell line (GM07492A). The results revealed IC50 values of 102.7, 143.4, and 253.1 µg/mL for BRPE, DSE, and DLE, respectively. The extracts were also evaluated for their genotoxic potential in the micronucleus assay in Chinese hamster lung fibroblasts cells (V79), showing the absence of genotoxicity. The BRPE was investigated for its potential in vivo toxicity in the zebrafish model. Concentrations of 0.8-6.3 mg/L were safe for the animals, with a LC50 of 9.37 mg/L. Of the 11 compounds isolated from BRPE, medicarpin showed a selective cytotoxic effect against the HeLa cell line. These are the initial steps to determine the toxicological potential of Brazilian red propolis.

Antigenotoxic, antiproliferative and antimetastatic properties of a combination of native medicinal plants from Argentina.

ETHNOPHARMACOLOGICAL RELEVANCE: Jarilla is the common name of an appreciated group of native plants from the semi-arid region in Argentina (Larrea cuneifolia Cav., Larrea divaricata Cav. and Zuccagnia punctata Cav.) that have been historically consumed to heal respiratory, musculoskeletal and skin ailments, as well as recommended for weakness/tiredness, hypertension, diabetes and cancer treatment. It was previously reported that some biological properties could be improved when these plants are used jointly. Infusions of a defined mixture, composed by three Jarilla species, L. cuneifolia: L. divaricata: Z. punctata (0.5:0.25:0.25) (HM2) showed synergistic and additive effect on antioxidant activity even after passing through the gastro-duodenal tract. AIM OF THE STUDY: The main purpose of this work was to evaluate antigenotoxic, antitumor, and anti-metastatic properties of the Jarilla species that grow in the Northwest of Argentina and a herbal combination of them. MATERIAL AND METHODS: Infusions of Jarilla mixture (HM2), and of each single plant species were prepared. Phenolic profiles of infusions were analyzed by HPLC-ESI-MS/MS and two relevant chemical markers were quantified. The antigenotoxic activity was evaluated by using the Ames test and the Cytokinesis-Block Micronucleus (CBMN) assay against direct mutagens. Evaluations of both cytotoxicity and antiproliferative effects were conducted on tumor and non-tumor cell lines. Both in vivo tumoral growth and metastasis inhibition were evaluated by using a carcinoma model on Balb/c mice. RESULTS: HM2 mix could suppress genetic and chromosome mutations induced by 4-nitro-o-phenylendiamine (4-NPD) and doxorubicin. Herbal mixture and single plant infusions showed cytotoxic effect against mammary, uterus, and brain tumoral cells without a selective action vs normal human cell line. HM2 mix was able to reduce mammary tumor mass on the Balb/c mice model and showed a significant reduction in the number of metastatic nodules in the lungs. CONCLUSIONS: Our results suggest that the combinations of three Jarilla species from northwest Argentina would be a promising alternative to treat or slow down the development of chronic diseases, such as cancer.

Evaluation of cytoprotective effects of compounds isolated from Copaifera langsdorffii Desf. against induced cytotoxicity by exposure to methylmercury and lead.

Copaifera langsdorffii L. is one of the most known medicinal species in Brazil. Its leaves are rich in phenolic compounds with potential biological activities as an antioxidant and chelating agent. This paper reports the isolation of four compounds from the hydroalcoholic extract of the leaves of C. langsdorffii and the investigation of their possible cytoprotective effects against heavy metal poisoning. Quercitrin (1), afzelin (2), 3,5-di-O-(3-O-methyl galloyl) quinic acid (3) and 4,5-di-O-(3-O-methyl galloyl) quinic acid (4), were associated with toxic doses of methylmercury and lead and evaluated by Alamar blue cell viability assays in HepG2 and PC12. The compounds displayed significant cytoprotective effect for the HepG2 cell line against both metals. Compounds 1-4 did not protect PC12 cells against methylmercury induced-cytotoxicity, but at lower concentrations, they protected against lead induced-cytotoxicity. The evaluated compounds showed a promising cytoprotection effect against exposure to heavy metals and should be further investigated as protective agents.

Biological properties of volatile oil from Brazilian brown propolis

ABSTRACT Propolis, is a bee product collected from exudates and flower buds of several plants, has strong aroma and several biological applications. This study aimed at evaluating the chemical composition and in vitro antioxidant, antibacterial and cytotoxic properties of volatile oil from Brazilian brown propolis. It was extracted by hydrodistillation and analyzed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. Volatile oil from brown propolis exhibited strong antibacterial activity against H. pylori (MIC 3.25 µg/ml), Mycobacterium tuberculosis (MIC 50 µg/ml) and M. avium (MIC 62.5 µg/ml). It was evaluated in vitro for antioxidant activity by DPPH (IC50 25.0 µg/ml) and ABTS (IC50 30.1 µg/ml) methods. Its cytotoxic property was evaluated in normal (human fibroblasts, GM07429A) and tumor (MCF-7-human breast adenocarcinoma; HeLa-human cervical adenocarcinoma and M059J-human glioblastoma) cell lines. IC50 values were 81.32 µg/ml for GM07429A and 85.00, 129.40 and 84.12 µg/ml for MCF-7, HeLa and M059J cells, respectively. Three major dereplicated components of volatile oil from brown propolis were acetophenone (15.2%), nerolidol (13.3%), and spathulenol (11.6%). Our results contribute to a better understanding of the chemical and biological properties of Brazilian brown propolis and provide evidence for its potential medicinal use.

Eugenia pyriformis Cambess: a species of the Myrtaceae family with bioactive essential oil.

Eugenia species have been appreciated for their edible fruits and medicinal properties. This paper aims to investigate the chemical composition and in vitro antileishmanial, antifungal and antiproliferative activities of essential oil from aerial parts of Eugenia pyriformis (EP-EO). The oil showed strong antileishmanial activity against promastigote forms of Leishmania amazonensis (IC50 = 2.16 µg/mL). It also exhibited high antifungal activity against Malassezia furfur (MIC = 30 µg/mL), which was determined by the broth microdilution method. Its antiproliferative activity was evaluated against the following cells: GM07429A (normal cell), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma) and M059J (human glioblastoma). Its major constituents, which were determined by GC-FID and GC-MS, were limonene (14.8%), nerolidol (11.0%), α-cadinol (10.3%), caryophyllene oxide (9.9%) and ß-pinene (7.1%). These results showed, for the first time, the effectiveness of EP-EO as a natural product which has promising biological activities, a fact that enables its ethnopharmacological use.