In vitro attenuation of classic metastatic melanoma­related features by highly diluted natural complexes: Molecular and functional analyses.

Metastasis is responsible for the majority of deaths among patients with malignant melanoma. Despite recent advances, the majority of current and modern therapies are ineffective and/or financially unfeasible. Thus, in this study, we investigated two low­cost highly­diluted natural complexes (HDNCs) that have been shown to be effective against malignant melanoma in a murine model in vivo. The aim of this study was to determine the mechanisms through which these HDNCs directly affect melanoma cells, either alone or in an artificial tumor microenvironment, suppressing the metastatic phenotype, thus explaining previous in vivo effects. For this purpose, HDNC in vitro treatments of B16­F10 melanoma cells, alone or in co­culture with Balb/3T3 fibroblasts, were carried out. Molecular biology techniques and standard functional assays were used to assess the changes in molecule expression and in cell behaviors related to the metastatic phenotype. Melanoma progression features were found to be regulated by HDNCs. Molecules related to cell adhesion (N­cadherin, ß1­integrin and CD44), and migration, extracellular matrix remodeling and angiogenesis were modulated. The cell migratory, invasive and clonogenic capacities were reduced by the HDNCs. No loss of cell proliferation or viability were observed. On the whole, the findings of this study indicate that HDNCs directly reprogram, molecularly and functionally, melanoma cells in vitro, modulating their metastatic phenotype. Such findings are likely to be responsible for the attenuation of tumor growth and lung colonization previously observed in vivo.

In vitro characterization of cutaneous immunotoxicity of immortalized human keratinocytes (HaCaT) exposed to reactive and disperse textile dyes.

Several synthetic dyes are used by textile industry for supplying the market of colored clothes. However, these chemicals have been associated with a variety of adverse human health effects, including textile dermatitis. Thus, there is a growing concern to identify textile dyes potentially as skin immunotoxicants. The aim of this in vitro study was to characterize the immunotoxic potential of reactive (Reactive Green 19 [RG19], Reactive Blue 2 [RB2], Reactive Black 5 [RB5]) and disperse (Disperse Red 1 [DR1]) textile dyes using a dermal cell line. For this purpose, a cell-based approach was conducted with immortalized human keratinocytes (KC) (HaCaT) using selected biomarkers of cutaneous inflammation including modulation of matrix metalloproteinases (MMP), oxidative stress such as reactive oxygen species (ROS) generation, and inflammatory cytokine profile. DR1 was the only dye able to trigger an immune response such as release of IL-12 cytokine, a potent co-stimulator of T helper 1 cell, which may be considered as a skin immunotoxicant. The reactive dyes including RB5 that were previously reported as skin sensitizers failed to induce inflammatory reactions under the conditions tested. The reactive dyes studied may pose a risk to human KC by induction of effects related to modulation of MMP-2 (RB5) and -9 (RB5 and RB2) and generation of ROS (RG19 and RB2). Thus, all these dyes need to be used with caution to avoid undesirable effects to consumers who may be exposed dermally.

Antiulcerogenic activity of hydroalcoholic extract of Achillea millefolium L.: involvement of the antioxidant system.

UNLABELLED: Achillea millefolium L. is a member of the Asteraceae family that is commonly referred to as "yarrow" and has been used in folk medicine against several disturbances including skin inflammations, spasmodic and gastrointestinal disorders, as well as hepato-biliary complaints. AIM OF THE STUDY: In the present study, we evaluated the efficacy of a hydroalcoholic extract from the Achillea millefolium (HE) for gastroprotective properties and additional mechanism(s) involved in this activity. MATERIAL AND METHODS: Rats were treated with HE and subsequently exposed to both acute gastric lesions induced by ethanol P.A. and chronic gastric ulcers induced by 80% acetic acid. Following treatment, glutathione (GSH) levels and superoxide dismutase (SOD) activity were measured. The activity of myeloperoxidase (MPO) and histological and immunohistochemical analysis were performed in animals with acetic acid-induced gastric ulcers. RESULTS: Oral administration of HE (30, 100 and 300mg/kg) inhibited ethanol-induced gastric lesions by 35, 56 and 81%, respectively. Oral treatment with HE (1 and 10mg/kg) reduced the chronic gastric ulcers induced by acetic acid by 43 and 65%, respectively, and promoted significant regeneration of the gastric mucosa after ulcer induction denoting increased cell proliferation, which was confirmed by PCNA immunohistochemistry. HE treatment prevented the reduction of GSH levels and SOD activity after acetic acid-induced gastric lesions. In addition, HE (10mg/kg) inhibited the MPO activity in acetic acid-induced gastric ulcers. CONCLUSIONS: The results of the present study indicate that the antioxidant properties of HE may contribute to the gastroprotective activity of this extract.

Muscarinic-dependent inhibition of gastric emptying and intestinal motility by fractions of Maytenus ilicifolia Mart ex. Reissek.

ETHNOPHARMACOLOGICAL RELEVANCE: Maytenus ilicifolia Mart. ex. Reissek (Celastraceae) is widely used in Brazilian folk medicine to treat gastric disturbances. AIM OF THE STUDY: This work intended to characterize the effects of Maytenus ilicifolia on gastrointestinal motility. MATERIALS AND METHODS: Gastric emptying and intestinal transit were measured in the same animal. Mice received a semisolid marked with phenol red, half an hour after treatment with extracts. The amount of marker in the stomach and the distance reached in the intestine after 15 min were measured as index of gastrointestinal emptying and intestinal transit, respectively. RESULTS: Intraperitoneal administration of a flavonoid-rich extract potently reduced the gastric emptying (ED(50)=89 mg/kg) and the intestinal transit (ED(50)=31 mg/kg) of mice. Bio-guided purification of the flavonoid-rich extract by chemical partition with solvents of decreasing polarity yielded fraction insF with about 12-14 times higher activity than the initial flavonoid extract in both the gastric emptying and the intestinal transit. The inhibitory effects of the insF (9.7 mg/kg, i.p.) on gastric emptying and intestinal transit were reversed by co-administration of bethanechol (10 mg/kg, s.c.) but not by co-administration of metoclopramide (30 mg/kg, p.o.) indicating muscarinic but not dopaminergic interaction of the compounds of Maytenus. Chemical investigation of the insF fraction by HPLC-MS allowed the identification of 4 free flavonoids (catechin, epicatechin, quercetin and kaempferol), 29 flavonol glycosides and 8 tannins. The flavonol glycosides ranged from 1 to 4 monosaccharide units, having mainly quercetin and kaempferol as aglycone moieties, and the tannins were composed by catechin/epicatechin and/or afzelechin/epiafzelechin. CONCLUSIONS: Overall, the results indicate that the components of Maytenus ilicifolia have a potential use in the treatment of gastrointestinal motility disturbances such as diarrhea.