RESUMEN
The purpose of this study was to assess the protective effects of an ethanol extract derived from the red alga Gracilaria bursa-pastoris (Gmelin) Silva (GBE) on ultraviolet B (UVB)-irradiated human HaCaT keratinocytes. GBE exhibited scavenging activity against intracellular reactive oxygen species that were induced by either hydrogen peroxide or UVB radiation. In addition, both the superoxide anion and the hydroxyl radical were scavenged by GBE in cell-free systems. GBE absorbed light in the UVB range (280-320 nm) of the electromagnetic spectrum and lessened the extent of UVB-induced oxidative damage to cellular lipids, proteins, and DNA. Finally, GBE-treated keratinocytes showed a reduction in UVB-induced apoptosis, as exemplified by fewer apoptotic bodies. These results suggest that GBE exerts cytoprotective actions against UVB-stimulated oxidative stress by scavenging ROS and absorbing UVB rays, thereby attenuating injury to cellular constituents and preventing cell death.
Asunto(s)
Gracilaria , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Extractos Vegetales/uso terapéutico , Rayos Ultravioleta/efectos adversos , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Células Cultivadas , Fragmentación del ADN/efectos de los fármacos , Fragmentación del ADN/efectos de la radiación , Humanos , Radical Hidroxilo/metabolismo , Queratinocitos/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/efectos de la radiación , Extractos Vegetales/farmacología , Carbonilación Proteica/efectos de los fármacos , Carbonilación Proteica/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Superóxidos/metabolismoRESUMEN
The aim of this study is to examine the cumulative effects of prolonged intensive training with or without rapid weight changes (RWC) on salivary parameters of elite female Taekwondo (TKD) athletes. Ten elite female Taiwanese TKD athletes (ages: 21.3 ± 1.2 years of age, Ht 164.4 ± 5.6 cm) volunteered to participate in this study. Resting saliva samples were collected at 28-, 14-, 7-, and 1 day before and 1-, 7-, 21 days after a national competition. The levels of salivary immunoglobulin A (sIgA), cortisol, and lactoferrin were measured. In analyzing the anthropometric data, we found that a significant proportion (50%) of elite female TKD athletes had RWC shortly before and after a national competition. The participants were allocated either to the RWC or to the non-RWC group according to their weight change profiles. Our results showed that levels of sIgA and cortisol of athletes with RWC were significantly modulated during the study period. However, athletes without RWC only showed reduced lactoferrin after competition. The results presented here demonstrate that intensive training in combination with RWC affects the mucosal immunity and disrupts the cortisol stress response of elite female TKD athletes.