UHPLC-MS/MS Studies and Antiproliferative Effects in Breast Cancer Cells of Mexican Sargassum.

BACKGROUND: Sargassum is a marine organism that, under specific conditions, drastically increases its population damaging the environment and risking other organisms. However, sargassum could represent a source of bioactive compounds to treat different diseases such as cancer. Thus, aqueous, ethanolic, and ethyl acetate extracts of sargassum from Playa del Carmen, Mexico, were subjected to metabolomic and antiproliferative assays in breast cancer cells. OBJECTIVE: To evaluate the biological effect of different extracts of sargassum, its toxicity over Artemia salina and its antiproliferative effect tested in MCF-7, MDA-MB-231, and NIH3T3 cell lines. Finally, using UHPLC-MS/MS to identify the metabolites in each extract to correlate them with its antiproliferative effect. METHODS: The sargassum sample collection was carried out in September at three different points in Playa del Carmen, Quintana Roo, Mexico. The aqueous, ethanolic, and ethyl acetate extracts of Mexican sargassum were obtained by evaporation of solvent and lyophilization. Then, these extracts were evaluated in the cytotoxicity bioassay of Artemia salina. Next, its antiproliferative effect was assessed in MCF-7, MDA-MB-231, and NIH3T3 cell lines. Using UHPLC-MS/MS, the metabolites present in each extract were identified. Finally, docking studies on sphingosine kinase 1 (PDB ID: 3VZB) of sphingosine were carried out. RESULTS: The extracts from sargassum showed a greater effect in the antiproliferative assays in cells than in cytotoxic assays in Artemia salina. The ethanolic extract obtained from sargassum showed the best antiproliferative activity in MCF7 and MDA-MB-231 cells. Despite its antiproliferative effect on NIH3T3 cells, an additional extract is required indicating that this extract has compounds that could have a better effect on cancer cells in fibroblast (NIH3T3). The UHPLC-MS/MS of ethanolic and the ethyl acetate extract showed that these extracts have compounds such as sphinganine C16, N, N-Dimethylsphingosine compound, and that it could be possible that the effect observed is due to their metabolites which could be ligands for the sphingosine kinase 1 as demonstrated by docking studies. CONCLUSION: The ethanolic extract obtained from sargassum has better antiproliferative activity, despite not having a cytotoxic effect in Artemia salina. The antiproliferative effect could be related to the sphinganine C16, N,NDimethylphingosine identified with more abundance by UHPLC-MS/MS. In addition, these metabolites could be targets of sphingosine kinase 1.

Antioxidant Extracts of Nettle (Urtica dioica) Leaves: Evaluation of Extraction Techniques and Solvents.

Nettle (Urtica dioica) is a great source of bioactive compounds. The objective of this study was to evaluate the extraction techniques (ultrasound, without stirring, and stirring), solvents (methanol, water, and ethanol), and extraction times (1-4 h) to maximize antioxidant capacity of the Urtica dioica extracts. In the case of total phenolic content (TPC) and ABTS•+ (2,2-azino-bis(3-etilbenzotiazolin)-6-sulfonic acid) free radical scavenging values, ultrasound extraction was the most efficient method, while the best results of DPPH• (1,1-diphenyl-2-picrylhydrazyl) assay in nettle extracts (91.08%) were obtained using stirring extraction, water as solvent, and 3 h of extraction time. Based on the obtained mathematical models, the optimization revealed that the best extraction conditions were ultrasound treatment with water as solvent and an extraction time of 3.15 h, obtaining values of 21.9 mg eq gallic acid/g dried nettle for TPC, 71.8% for %ABTS•+ and 86.6% for %DPPH•. This work proves that aqueous extract of nettle leaves through the ultrasound technique is an important source of natural antioxidants and can be considered a potential alternative to synthetic antioxidants.

Evaluation of easy-removing antioxidant films of chitosan with Melaleuca alternifolia essential oil.

Chitosan - tea tree essential oil (TTEO) films were obtained as a new biodegradable material. Malic acid or lactic acid solvents were evaluated to obtain easy-removing films. The microstructure by SEM and FT-IR, the thermal properties by TGA/DSC, the mechanical properties, the water vapor permeability, the antioxidant (DPPH• and ABTS•+) activity and the optical properties of the formulated films were evaluated. A complete dissolution of the film in water was obtained. The elongation to break was higher in the films with malic acid (145.88-317.33%), comparing with those with lactic acid (25.54-44.08%). Chitosan film obtained in malic acid with TTEO showed the highest antioxidant activity. The colour and transparency of the samples did not suffer significant variations by TTEO addition. Films showed good UV-barrier properties, with a slightly improvement by TTEO addition. The films obtained showed a great potential for food packaging applications.

Selection of a GPER1 Ligand via Ligand-based Virtual Screening Coupled to Molecular Dynamics Simulations and Its Anti-proliferative Effects on Breast Cancer Cells.

BACKGROUND: Recent reports have demonstrated the role of the G Protein-Coupled Estrogen Receptor 1 (GPER1) on the proliferation of breast cancer. The coupling of GPER1 to estrogen triggers cellular signaling pathways related to cell proliferation. OBJECTIVE: Develop new therapeutic strategies against breast cancer. METHOD: We performed in silico studies to explore the binding mechanism of a set of G15 /G1 analogue compounds. We included a carboxyl group instead of the acetyl group from G1 to form amides with several moieties to increase affinity on GPER1. The designed ligands were submitted to ligand-based and structure-based virtual screening to get insights into the binding mechanism of the best designed compound and phenol red on GPER1. RESULTS: According to the in silico studies, the best molecule was named G1-PABA ((3aS,4R,9bR)-4-(6- bromobenzo[d][1,3]dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-carboxylic acid). It was synthesized and assayed in vitro in breast cancer (MCF-7 and MDA-MB-231) and normal (MCF-10A) cell lines. Experimental studies showed that the target compound was able to decrease cell proliferation, IC50 values of 15.93 µM, 52.92 µM and 32.45 µM in the MCF-7, MDA-MB-231 and MCF-10A cell lines, respectively, after 72 h of treatment. The compound showed better IC50 values without phenol red, suggesting that phenol red interfere with the G1-PABA action at GPER1, as observed through in silico studies, which is present in MCF-7 cells according to PCR studies and explains the cell proliferation effects. CONCLUSION: Concentration-dependent inhibition of cell proliferation occurred with G1-PABA in the assayed cell lines and could be due to its action on GPER1.

High hydrostatic pressure at low temperature as a quarantine treatment to improve the quality of fruits.

Application of high hydrostatic pressure has been proposed as an alternative quarantine process for the Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), one of the most important insects infesting mangoes, citrus fruits, and other fruits in Mexico and other Latin American countries. The present study was performed to determine the effect of high pressure treatments at 0 degrees C on the survivorship of eggs and larvae of this pest. The effect of time and pressure level at near-freezing temperatures on the egg hatch and survival of larvae is discussed. Eggs and larvae were pressurized at 25, 50, 75, 100, or 150 MPa for 0, 5, 10, or 20 min at 0 degrees C. Hatch was recorded for 1-, 2-, 3-, and 4-day-old pressurized eggs. For pressurized larvae (first, second, and third instars), percentage of survival was registered. Further, third instars were studied for their ability to pupate and develop to adulthood. The results showed that eggs had higher resistance than larvae to pressure. Larvae were not able to resist pressure treatments at 75 MPa for 20 min at 0 degrees C. Treatments at 150 MPa for 20 min at 0 degrees C were needed to destroy all eggs and larvae of A. ludens, indicating that this process might be useful as a quarantine method for infested fruits. However, more studies involving combination of high hydrostatic pressure at low temperature with precooling treatments are needed in order to decrease the pressure level to avoid fruit damage.

Cuantificación de la activación cerebral mediante exploración PET relacionada con estados de alerta o relajación / Quantification of the cerebral activation by means of PET exploration related with arousal or relaxation states

En un reciente estudio publicado en esta revista, empleamos una técnica de cuantificación de la actividad PET que nos permite la detección de áreas del cerebro con una actividad patológica frente a una base normativa. En nuestro esfuerzo por comprobar la eficacia del método estamos desarrollando diversos estudios para verificar su validez. En el presente trabajo mostramos que es posible observar la actividad cerebral de un sujeto control en diferentes niveles de alerta. En particular, la actividad de regiones frontales y parietales del hemisferio derecho se encuentran incrementadas como consecuencia de un estado de alerta mayor respecto del estado de relajación.

In a recent study published in this journal, we use a quantification technique for the PET exploration that allows us the detection of areas of the brain with a pathological activity compared to a normative database. In our effort to check the effectiveness of the method diverse studies have been developed to verify the validity of the method. In the present experiment, we show an interesting result that confirms that is possible to observe the brain activity of a healthy control in different levels of arousal. In particular, the activity of frontal and parietal regions of the right hemisphere is enhanced as a consequence of an increased level of arousal compared to the relaxation state.

Treatment effects of combined radio-frequency current and a 900 nm diode laser on leg blood vessels.

BACKGROUND AND OBJECTIVES: Effective laser treatment of leg veins remains a major challenge. The present study examined the safety and efficacy of a new technology for leg vein treatment combining 900 nm diode laser with radiofrequency (RF) current. STUDY DESIGN/MATERIALS AND METHODS: Forty patients, skin types II-IV, received a maximum of three treatments on 1-4 mm leg veins at 2-week intervals with a 900 nm diode laser (250 millisecond exposure time, average fluence 60 J/cm2) and RF (energy 100 J/cm3). Results were assessed after each treatment and at 2 and 6 months after the final session. Patients rated their satisfaction with the clinical outcome on a five-item scale. Clinician and computer analysis of the clinical photography was also performed, in addition to histological assessment. RESULTS: One or two sessions were required in the majority of patients. Shortly after treatment, histology revealed contracted vessels with perivascular edema. Side effects were extremely rare. The clinician 2- and 6-month assessments showed that 70% and 82.5% of subjects, respectively, achieved over 50% clearance, with patient and computer assessments lower and slightly higher, respectively. Treatments showed greater efficacy on thicker vessels and in the darker skin types. CONCLUSIONS: The success of the treatment, minimal side effects, and patient comfort suggest that this combination is an effective, safe technique for leg vein treatment. When compared to previous studies using diode laser alone, the very low fluence needed to achieve vessel clearance emphasizes the role of RF energy.