Two ozonation procedures for sunflower oils at different applied ozone dosages were carried out. Ozone was obtained from medicinal oxygen and from air. Peroxide, acidity, and iodine indexes, along with density, viscosity and antimicrobial activity were determined. The fatty acid compositions of the samples were analyzed using GC. The content of oxygen was determined using an elemental analysis. Electronic Paramagnetic Resonance was used to measure the organic free radicals. The reactions were achieved up to peroxide index values of 658 and 675 mmolequiv kg^–1 using medicinal oxygen and air for 5 and 8 hours, respectively. The samples of ozonized sunflower oil did not present organic free radicals, which is a very important issue if these oils are to be used as drugs. The ozonation reaction is more rapid with medicinal oxygen (5 hours) than with air (8 hours). Ozonized sunflower oil with oxygen as an ozone source was obtained with high potential for antimicrobial activity.<br><br>Se ha aplicado dos procedimientos de ozonización a aceites de girasol a diferentes dosis de ozono, obteniendo el ozono a partir de oxígeno medicinal y de aire. Se han determinado los índices de peróxido, yodo y acidez conjuntamente con la densidad, viscosidad y la actividad antimicrobiana. La composición de ácidos grasos fue analizada mediante CG. El contenido de oxígeno fue determinado mediante Análisis Elemental. Se utilizó la resonancia paramagnética electrónica para medir los radicales libres orgánicos. Las reacciones fueron realizadas hasta valores de índice de peróxidos de 658 y 675 mmol-equiv kg^–1 usando oxígeno medicinal y aire durante 5 y 8 horas, respectivamente. Las muestras de aceite de girasol ozonizado no presentaron radicales libres orgánicos, lo cual es muy importante en el caso de que estos aceites sean utilizados en medicina. La reacción de ozonización es más rápida cuando se utiliza oxígeno medicinal (5 horas) que el aire (8 horas). El aceite de girasol ozonizado con oxígeno como fuente de ozono presentó mayor potencial de actividad antimicrobiana

Alzheimer’s disease is a neurodegenerative disorder that is the leading cause of dementia in elderly patients. Amyloid-β peptide (1–42 oligomers) has been identified as a neurotoxic factor, triggering many neuropathologic events. In this study, 15 chalcones were synthesized employing the Claisen–Schmidt condensation reaction, starting from a compound derived from fomannoxine, a natural benzodihydrofuran whose neuroprotective activity has been proven and reported, and methyl aromatic ketones with diverse patterns of halogenated substitution. As a result, chalcones were obtained, with good to excellent reaction yields from 50 to 98%. Cytotoxicity of the compounds was assessed, and their cytoprotective effect against the toxicity associated with Aβ was evaluated on PC-12 cells. Out of the 15 chalcones obtained, only the 4-bromo substituted was cytotoxic at most tested concentrations. Three synthesized chalcones showed a cytoprotective effect against Aβ toxicity (over 37%). The 2,4,5-trifluoro substituted chalcone was the most promising series since it showed a cytoprotective impact with more than 60 ± 5% of recovery of cellular viability; however, 3-fluoro substituted compound also exhibited important values of recovery (50 ± 6%). The fluorine substitution pattern was shown to be more effective for cytoprotective activity. Specifically, substitution with fluorine in the 3,5-positions turned out to be particularly effective for cytoprotection. Furthermore, fluorinated compounds inhibited the aggregation rate of Aβ, suggesting a dual effect that can be the starting point of new molecules with therapeutic potential.

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RESUMENEfecto antioxidante de una formulación de aceite de teobroma ozonizado sobre la piel de ratas con daño inflamatorio.El objetivo de este estudio fue determinar si una formulación cosmética elaborada con aceite de teobroma ozonizado puede ejercer efectos beneficiosos en la restauración de la actividad antioxidante sobre la piel de ratas previamente irradiadas con luz ultravioleta. Fue aplicada 0,5 g de la formulación sobre la piel de ratas durante cinco días. La actividad de las enzimas superóxido dismutasa (SOD), glutatión peroxidasa (GPx), y catalasa fueron determinadas en homogeneizado de piel de ratas. Los contenidos de malonildialdehído (MDA), dienos conjugados (DC) e hidroperóxidos totales (HPT) fueron considerados como los biomarcadores de daño oxidativo. Con todos estos parámetros fueron determinados las actividades antioxidantes y oxídantes, índice redox y grado de estrés oxidativo. La actividad antioxidante total fue incrementada significativamente, mientras que el índice redox, la actividad oxidante y el grado de estrés oxidativo disminuyó significativamente, en ratas dañadas tratadas con la formulación. Estos resultados evidencian las propiedades antioxidantes de la formulación cosmética debido a la estimulación de enzimas antioxidantes tales como SOD o GPx, previniendo el daño en la piel inducido por radiación ultravioleta. PALABRAS CLAVE: Aceite de teobroma ozonizadoActividad antioxidante -Actividad oxidante -Estrés oxidativo -Formulación cosmética.SUMMARY Antioxidant effect of an ozonized theobroma oil formulation on damaged-inflammatory rat skin.The aim of this study was to determine whether a cosmetic formulation elaborated with ozonized theobroma oil may exert beneficial effects in the restoring of the antioxidant activity on the skin of rats previously irradiated with ultraviolet light. 0.5 g of the formulation was applied on the skin of rats for five days. Superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activity were determined in a homogenate of rat skin. Malondialdehyde (MDA), conjugated dienes (CD) and total hydroperoxide (THP) content were determined as biomarkers of oxidative stress. Using these parameters, antioxidant and oxidant activity, redox index and oxidative stress grade were determined. The total antioxidant activity was significantly increased while the redox index, total oxidant activity and oxidative stress grade decreased significantly in damaged rats treated with the formulation. These results show the antioxidant properties of the cosmetic formulation due to the stimulation of antioxidant enzymes such as SOD and GPx, preventing skin injury induced by ultraviolet irradiation.

The quinuclidine scaffold has been extensively used for the development of nicotinic acetylcholine receptor (nAChR) agonists, with hydrophobic substituents at position 3 of the quinuclidine framework providing selectivity for α7 nAChRs. In this study, six new ligands (4−9) containing a 3-(pyridin-3yloxy)quinuclidine moiety (ether quinuclidine) were synthesized to gain a better understanding of the structural−functional properties of ether quinuclidines. To evaluate the pharmacological activity of these ligands, two-electrode voltage-clamp and singlechannel recordings were performed. Only ligand 4 activated α7 nAChR. Ligands 5 and 7 had no effects on α7 nAChR, but ligands 6, 8, and 9 potentiated the currents evoked by ACh. Ligand 6 was the most potent and efficacious of the potentiating ligands, with an estimated EC 50 for potentiation of 12.6 ± 3.32 μM and a maximal potentiation of EC 20 ACh responses of 850 ± 120%. Ligand 6 increased the maximal ACh responses without changing the kinetics of the current responses. At the single-channel level, the potentiation exerted by ligand 6 was evidenced in the low micromolar concentration range by the appearance of prolonged bursts of channel openings. Furthermore, computational studies revealed the preference of ligand 6 for an intersubunit site in the transmembrane domain and highlighted some putative key interactions that explain the different profiles of the synthesized ligands. Notably, Met276 in the 15′ position of the transmembrane domain 2 almost abolished the effects of ligand 6 when mutated to Leu. We conclude that ligand 6 is a novel type I positive allosteric modulator (PAM-I) of α7 nAChR.