In vitro Safety Assessment of Extracts and Compounds From Plants as Sunscreen Ingredients.

This work investigated the safety of extracts obtained from plants growing in Colombia, which have previously shown UV-filter/antigenotoxic properties. The compounds in plant extracts obtained by the supercritical fluid (CO2) extraction method were identified using gas chromatography coupled to mass spectrometry (GC/MS) analysis. Cytotoxicity measured as cytotoxic concentration 50% (CC50) and genotoxicity of the plant extracts and some compounds were studied in human fibroblasts using the trypan blue exclusion assay and the Comet assay, respectively. The extracts from Pipper eriopodon and Salvia aratocensis species and the compound trans-ß-caryophyllene were clearly cytotoxic to human fibroblasts. Conversely, Achyrocline satureioides, Chromolaena pellia, and Lippia origanoides extracts were relatively less cytotoxic with CC50 values of 173, 184, and 89 µg/mL, respectively. The C. pellia and L. origanoides extracts produced some degree of DNA breaks at cytotoxic concentrations. The cytotoxicity of the studied compounds was as follows, with lower CC50 values representing the most cytotoxic compounds: resveratrol (91 µM) > pinocembrin (144 µM) > quercetin (222 µM) > titanium dioxide (704 µM). Quercetin was unique among the compounds assayed in being genotoxic to human fibroblasts. Our work indicates that phytochemicals can be cytotoxic and genotoxic, demonstrating the need to establish safe concentrations of these extracts for their potential use in cosmetics.

The Antiproliferative Activity of a Mixture of Peptide and Oligosaccharide Extracts Obtained from Defatted Rapeseed Meal on Breast Cancer Cells and Human Fibroblasts.

Oligosaccharide and peptide extracts obtained separately from defatted rapeseed meal (DRM) have shown antiproliferative activities on the MCF-7 breast cancer cell line. However, oligosaccharide extracts were not tested on human fibroblasts and have low yields. The objective of the present study was to combine two antiproliferative extracts, the peptides and oligosaccharides, that were obtained independently with commercial enzymes from DRM, allowing improvement of the mass yield and antiproliferative activity. The DRM was solubilized in an alkaline medium to obtain an insoluble meal residue (IMR) and an alkaline extract (RAE). To produce the oligosaccharide extract from IMR, three enzymes and different enzyme/substrate ratios were used. The oligosaccharide extract (molecular weight <30 kDa) recovered with the commercial enzyme. Endogalacturonase showed an 80% inhibition on MCF-7 cells at 20 mg/mL. The combination of this oligosaccharide extract with the peptide extract (obtained with Alkalase 2.4 L from a RAE at 10 mg/mL) inhibited 84.3% of MCF-7 cells proliferation at a concentration of 20 mg/mL, exhibiting no cytotoxic effects on fibroblasts. The mass yield of the extract pool was 27.07% (based on initial DRM). It can be concluded that a mixture of antiproliferative extracts was produced from DRM which was selective against MCF-7 cells.

Flower Extracts from Ornamental Plants as Sources of Sunscreen Ingredients: Determination by In Vitro Methods of Photoprotective Efficacy, Antigenotoxicity and Safety.

Plants are sources of sunscreen ingredients that prevent cellular mutations involved in skin cancer and aging. This study investigated the sunscreen properties of the extracts from some ornamental plants growing in Colombia. The UV filter capability of the flower extracts obtained from Rosa centifolia L., Posoqueria latifolia (Rudge) Schult, and Ipomoea horsfalliae Hook. was examined. Photoprotection efficacies were evaluated using in vitro indices such as sun protection factor and critical wavelength. UVB antigenotoxicity estimates measured with the SOS Chromotest were also obtained. Extract cytotoxicity and genotoxicity were studied in human fibroblasts using the trypan blue exclusion and Comet assays, respectively. Major compounds of the promising flower extracts were identified by UHPLC-ESI+-Orbitrap-MS. The studied extracts showed high photoprotection efficacy and antigenotoxicity against UVB radiation, but only the P. latifolia extract showed broad-spectrum photoprotection at non-cytotoxic concentrations. The P. latifolia extract appeared to be safer for human fibroblast cells and the R. centifolia extract was shown to be moderately cytotoxic and genotoxic at the highest assayed concentrations. The I. horsfalliae extract was unequivocally cytotoxic and genotoxic. The major constituents of the promising extracts were as follows: chlorogenic acid, ecdysterone 20E, rhamnetin-rutinoside, cis-resveratrol-diglucoside, trans-resveratrol-diglucoside in P. latifolia; quercetin, quercetin-glucoside, quercetin-3-rhamnoside, kaempferol, kaempferol-3-glucoside, and kaempferol-rhamnoside in R. centifolia. The potential of the ornamental plants as sources of sunscreen ingredients was discussed.

[Identificación de fármacos reguladores de la actividad del promotor Egr-1 en fibroblastos humanos transducidos con AdΔegr-1-Luc7]. / Identification of drugs as regulators on the activity of Egr-1 promoter in human fibroblasts transduced with AdΔegr-1-Luc7.

INTRODUCCIÓN: La proteína de respuesta temprana a crecimiento 1 (EGR-1) es un factor de transcripción involucrado en la diferenciación y la proliferación celulares, cuya expresión es regulada por su promotor en respuesta a diversos factores físicos y químicos, y a fármacos. Aquí se describen algunos de los principales efectos de los fármacos esteroides y del factor de crecimiento epitelial 1 (EGF-1) sobre la actividad del promotor, mediante un sistema reportero transducido por el adenovirus AdΔegr-1-Luc7 en fibroblastos primarios humanos. MÉTODO: Los fibroblastos primarios humanos fueron cultivados en pase 5, transducidos con AdΔegr-1-Luc7 y expuestos a betametasona, hidrocortisona, dexametasona, testosterona, beta-estradiol y EGF-1 durante 1, 3 y 6 horas. La actividad de reportero fue cuantificada por luminometría y ajustada a la concentración de proteínas totales. RESULTADOS: La actividad del promotor en presencia de betametasona, hidrocortisona, dexametasona, testosterona y beta-estradiol fue similar a la actividad basal del promotor a las 1, 3 y 6 horas. El control positivo mostró una actividad 17.8 veces mayor a las 6 horas (p ≤ 0.05). De manera similar, las células expuestas a EGF-1 mostraron una actividad 22.07 veces mayor que las células sin fármaco. CONCLUSIÓN: La actividad del promotor Egr-1 en fibroblastos humanos es regulada negativamente por los fármacos esteroides y positivamente por el EGF-1. INTRODUCTION: The early growth response protein (EGR-1) is a transcription factor involved in cell differentiation and proliferation, whose expression is regulated by its promoter in response to various physical, chemical and drug factors. Hereby, we describe some of the main effects of steroid drugs and EGF-1 on promoter activity, through a reporter system transduced by AdΔegr-1-Luc7 in human primary fibroblasts (HPF). METHODS: Human primary fibroblasts transduced with AdΔegr-1-Luc7 were exposed to betamethasone, hydrocortisone, dexamethasone, testosterone, beta-estradiol, and EGF-1 during 1, 3 and 6 h. Reporter assay was quantified by luminometry. RESULTS: The activity of the promoter in presence of betamethasone, hydrocortisone, dexamethasone, testosterone and beta-estradiol were similar to the basal activity of the promoter at 1, 3 and 6 h. The positive control showed an activity 17.8 folds higher (p ≤ 0.05) at 6 h. EGF-1 showed activity of 22.07 folds greater than cells without drug. CONCLUSION: The activity of the EGR-1 promoter in human fibroblasts is negatively regulated by steroid drugs and positively by the EGF-1.

Passiflora tarminiana fruits reduce UVB-induced photoaging in human skin fibroblasts.

Skin aging is a complex process that is strongly affected by UV radiation, which stimulates the production of reactive oxygen species (ROS) in the epidermis and dermis and subsequently causes skin damage. Among the major consequences are increased collagen degradation and reduced collagen synthesis. Previous reports have demonstrated the beneficial effects of polyphenols for healthy skin. Passiflora tarminiana Coppens & V.E. Barney, a species of the Passifloraceae family, is widely distributed in South America and is rich in flavonoids. We show that UVB radiation increases metalloproteinase 1 (MMP-1) and reduces procollagen production in human dermal fibroblast (HDF) cells in a dose- and time-dependent manner. We examined the antioxidant and antiaging effects of the extract and fractions of P. tarminiana fruits. The fractions showed high polyphenol content (620mg EAG/g) and antioxidant activity, as measured by ORAC (4097µmol ET/g) and ABTS (2992µmol ET/g) assays. The aqueous fraction drastically inhibited the collagenase enzyme (IC50 0.43µg/mL). The extract and fractions presented photoprotective effects by reducing UVB-induced MMP-1 production, increasing UVB-inhibited procollagen production, and decreasing ROS production after UVB irradiation in HDF. Finally, the polyphenol contents of the extracts and fractions from P. tarminiana were analyzed by HPLC-DAD-ESI-MSn, and procyanidins and glycosylated flavonoids were identified.

In vitro and in vivo antimalarial activity and cytotoxicity of extracts, fractions and a substance isolated from the Amazonian plant Tachia grandiflora (Gentianaceae)

Tachia sp. are used as antimalarials in the Amazon Region and in vivo antimalarial activity of a Tachia sp. has been previously reported. Tachia grandiflora Maguire and Weaver is an Amazonian antimalarial plant and herein its cytotoxicity and antimalarial activity were investigated. Spectral analysis of the tetraoxygenated xanthone decussatin and the iridoid aglyone amplexine isolated, respectively, from the chloroform fractions of root methanol and leaf ethanol extracts was performed. In vitro inhibition of the growth of Plasmodium falciparum Welch was evaluated using optical microscopy on blood smears. Crude extracts of leaves and roots were inactive in vitro. However, chloroform fractions of the root and leaf extracts [half-maximal inhibitory concentration (IC50) = 10.5 and 35.8 µg/mL, respectively] and amplexine (IC50= 7.1 µg/mL) were active in vitro. Extracts and fractions were not toxic to type MRC-5 human fibroblasts (IC50> 50 µg/mL). Water extracts of the roots of T. grandiflora administered by mouth were the most active extracts in the Peters 4-day suppression test in Plasmodium berghei-infected mice. At 500 mg/kg/day, these extracts exhibited 45-59% inhibition five to seven days after infection. T. grandiflora infusions, fractions and isolated substance have potential as antimalarials.

Bothrops pirajai snake venom L-amino acid oxidase: in vitro effects on infection of Toxoplasma gondii in human foreskin fibroblasts

The effect of an L-amino acid oxidase isolated from Bothrops pirajai snake venom (BpirLAAO-I) was investigated on infection of Toxoplasma gondii in human foreskin fibroblasts (HFF). The cytotoxic activity of BpirLAAO-I on HFF cells showed a dose-dependent toxicity with median cytotoxic dose (TD50) of 11.8 µg/mL. BpirLAAO-I induced considerable dose-dependent decrease in the T. gondii infection index under two different conditions, treatment of tachyzoites before infection or treatment of HFF cells after infection. A maximal inhibition of infection (56 percent) was found for treatment before infection, with a median inhibitory dose (ID50) at 1.83 µg/mL and selectivity index (SI) at 6.45. For treatment after infection, it was observed a maximal inhibition of infection at 65 percent, ID50 of 1.20 µg/mL and SI of 9.83. The treatment before infection was also effective to reduce intracellular parasitism up to 62 percent, although presenting higher values of ID50 (3.14 µg/mL) and lower values of SI (3.76). However, treatment after infection was not effective, suggesting that the enzyme seems to have no effect on the parasite intracellular replication for this condition. In conclusion, BpirLAAO-I was more effective to inhibit the infection of neighboring cells and consequently parasite dissemination than primary infection and parasite replication. Thus, the effect of BpirLAAO-I described herein could be taken into account for the development of new synthetic anti-parasite therapeutic agents.