Search

In this work we extend the toxicological studies of hot aqueous extract of A. satureioides (As-HAE) evaluating cytotoxic and apoptotic effects on human peripheral blood mononuclear cells (PBMCs). We also determine genotoxic action of this extract in vivo. In addition, the extract was chemically characterized. Finally, we established a comparison with previous data of cold aqueous extract. The As-HAE induced cytotoxicity on PBMCs determined by trypan blue dye exclusion (CC50 = 653 μg/mL) and MTT (CC50 = 588 μg/mL) assays being more toxic than cold extract. However, As-HAE as well as cold extract did not induce apoptosis measured by Hoechst 33258 staining, TUNEL assay, and DNA fragmentation analysis. The in vivo micronucleus test showed that As-HAE exerted cytogenotoxic effects on bone marrow of mice, contrary to what was observed with cold extract. The chemical study of As-HAE allowed identifying the flavonoids found in cold extract: luteolin, quercetin, and 3-O-methylquercetin, but at higher concentrations. We suggest that toxic effects induced by As-HAE could be due to high concentrations of these flavonoids. Given that As-HAE is the most used in folkloric medicine, its administration should be controlled in order to prevent potential cell damage.

Achyrocline satureioides is widely consumed as infusion or aperitif and shows important therapeutic properties. Previously, we reported absence of genotoxicity of cold aqueous extract (CAE) of A. satureioides by Allium test. However, one test cannot predict the genotoxic effects of a substance. Thus, the aim of this work was to investigate cytotoxicity, genotoxicity and apoptotic ability of CAE of A. satureioides. In addition, CAE was chemically characterized. The cytotoxicity was evaluated by Trypan blue and MTT assays. The apoptotic capacity was evaluated by Hoechst staining and DNA fragmentation-analysis. The genotoxicity was studied by comet assay (CA) and micronucleus test. The identification and quantification of flavonoids were performed by HPLC-ESI-MS/MS. The cytotoxicity studies indicated low toxicity of CAE. In addition, CAE did not induce apoptotic effects on human PBMCs. CAE did not show genotoxicity in vitro against Vero cells, at 10-50 μg/mL. CAE did not induce in vivo genotoxic effects, but it showed at high concentrations cytotoxicity by micronucleus assay. CAE presented flavonoids such as quercetin, 3-O-methylquercetin and luteolin. In conclusion, A. satureioides at popularly concentrations used, in aperitif or infusion, can be consumed safely because did not show any cytotoxic or genotoxic effects., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Minthostachys verticillata (peperina) is an aromatic and medicinal plant with several uses and ethnobotanical properties. Numerous studies have demonstrated that its essential oil (Mv-EO) presents antimicrobial capacity and shows immunomodulating and anti-allergic properties in human cell lines. Thus, the goal of this study was to investigate the main chemical composition, analyzed by GC-FID, and the cyto-genotoxic effects of Mv-EO, using Vero cells, human PBMCs and mice bone marrow cells. The Mv-EO was rich in pulegone 60.5% and menthone 18.2%. Our results clearly show that Mv-EO is not cyto-genotoxic in vitro nor in vivo. It not induced cytotoxic effects, as indicated by trypan blue dye exclusion and NRU assays both in Vero cells and human PBMCs. In addition, Mv-EO (100-1000 μg/mL) not induced apoptotic effects on human PBMCs, as indicated by Hoechst staining and DNA fragmentation analysis by agarose gel electrophoresis. The in vivo assay showed that Mv-EO (25-500 mg/kg) not increased the frequency of micronucleus in bone marrow cells of mice. Further, the ratio of polychromatic/normochromatic erythrocytes was not modified. These findings suggest that Mv-EO appears to be safe as a therapeutic agent., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Achyrocline satureioides (Asteraceae) is a medicinal plant traditionally used in Argentina for the treatment of intestinal infections and various digestive disorders. Its infusion is widely utilised for respiratory problems and viral infections. The objective of this study was to investigate cytotoxicity, virucidal and antiviral properties of the cold aqueous extract (CAE) and hot aqueous extract (HAE) of this plant against Western equine encephalitis virus (WEEV). Cytotoxicity in Vero cells was evaluated by maximum non-cytotoxic concentration (MNCC), neutral red (NR) uptake and MTT reduction methods. To study the antiviral activity of aqueous extracts, plaque reduction assay was performed after pre-treatment of host cells, adsorption, penetration and post-penetration of the virus. Extracellular virus inactivation was also analysed by the same method. Extracts showed strong inhibitory activity after virus penetration with selective index values of 32 (NR) and 63.3 (MTT) for the CAE, and 16.2 (NR) and 24.3 (MTT) for the HAE. Both extracts exhibited virucidal action with lower efficacy than their antiviral properties. The present results demonstrate that aqueous extracts of A. satureioides are active against WEEV. Further studies are needed in order to identify which compounds could be responsible for this effect, and how they exert antiviral action.

The methanolic extract of Verbascum thapsus was evaluated for its antiviral activity against the pseudorabies virus strain RC/79 (PrV), and also for its cytotoxic activity on Vero cells. The extract showed CC₅₀ values of 1100 µg mL⁻¹ and 1426 µg mL⁻¹ by NRU and MTT assays, respectively. The 50% inhibitory concentration of the extract for PrV plaque formation was determined at 35 µg mL⁻¹, and selectivity indices were 31.4 (NRU) and 40.7 (MTT). When cells were pre-treated with the extract prior to virus infection, the inhibition in plaque formation was 70%. PrV was highly inhibited when it was incubated with plant extract or when the extract was added during the adsorption phase (99%). However, no inhibitory effect was observed when the extract was added to the cells after the adsorption period. Thus, these results suggest that the methanolic extract of Verbascum thapsus may contain bioactive compound(s) that affect PrV mostly in the adsorption phase.

Achyrocline satureioides ("marcela del campo") is native to America. Numerous investigations have reported several bioactive properties such as anti-inflammatory, hepatoprotective, immunomodulatory, antimicrobial and antiviral. Nowadays, few medicinal plants have been scientifically evaluated to test its safety, efficacy and potential benefits, despite the great public interest in these herbs. The aim of this work was to evaluate the cytotoxic and genotoxic activities of cold aqueous extract obtained from A. satureioides using Allium cepa L test. The results demonstrated the absence of genotoxicity of the extract. Only higher concentrations induced cytotoxicity but interestingly this effect was reversible and was not associated with mutagenicity. The contribution of this research provides assurance of safety in the application of Achyrocline satureioides in treatment of microbial diseases and other pathologies helping to define selective toxicity.

Verbascum thapsus L. is a medicinal plant and has been used to treat numerous pulmonary diseases, asthma, inflammatory disease, spasmodic coughs and migraine headaches. Several studies have demonstrated that different extracts of V. thapsus present antimicrobial activity. Thus, the goal of this study was to evaluate the genotoxic and cytotoxic activities of a methanolic extract of Verbascum thapsus, using micronucleus test in mouse bone marrow. No toxicity in bone marrow was detected in the extract-treated groups. The methanolic extract of V. thapsus at doses of 100, 300 and 500 mg/kg, did not produce a significant increase in the frequency of MNPCE in bone marrow and neither altered the relationship PCE/NCE respect to negative control. These cytogenotoxic findings contribute the preclinical knowledge of methanolic extract of V. thapsus and provide security in its use as herbal medicine.

Baccharis articulata is native of América and traditionally used for the treatment of digestive disorders and urinary infections. Cytotoxicity of aqueous extracts of B. articulata was investigated in Vero cells. As the maximal non cytotoxic concentration has been established, this concentration has been used to evaluate antiviral and virucidal activities against Herpes suis virus type 1, member of the same subfamily of Herpes simplex virus. Aqueous extracts of B. articulata exhibited more than 95% of virucidal activity. These findings support their potential application as a disinfectant or antiseptic with low toxicity and provide a valuable knowledge to ethnopharmacology properties of Baccharis articulata.

The antiviral activity of alcoholic extracts of several species belonging to the Asteraceae, Labiatae, Plantaginaceae, Schizaceae, Umbelliferae, Usneaceae and Verbenaceae families has been studied. The tests were carried out in Vero celís-pseudorabies virus strain RC/79 (herpes suis virus) system. Eight plant extracts (Achyrocline satureioides, Ambrossia tenuifolia, Baccharis articulata, Eupatorium buniifolium, Mynthostachys verticillata, Plantago brasiliensis, Plantago mayor L and Verbascum thapsus) were able to inhibit at least 2 log, the viral infectivity.