Enhancement of Neurite Outgrowth by Warming Biomaterial Ultrasound Treatment.

Ultrasound is a method for enhancing neurite outgrowth because of its thermal effect. In order to reach the working temperature to enhance neurite outgrowth, long-time treatment by ultrasound is necessary, while acknowledging that the treatment poses a high risk of damaging nerve cells. To overcome this problem, we developed a method that shortens the ultrasonic treatment time with a warming biomaterial. In this study, we used Fe3O4 nanoparticle-embedded polycaprolactone (PCL) as a sonosensitized biomaterial, which has an excellent heating rate due to its high acoustic attenuation. With this material, the ultrasonic treatment time for enhancing neurite outgrowth could be effectively shortened. Ultrasonic treatment could also increase neuronal function combined with the warming biomaterial, with more promoter neuronal function than only ultrasound. Moreover, the risk of overexposure can be avoided by the use of the warming biomaterial by reducing the ultrasonic treatment time, providing better effectiveness.

Effect of Vetiveria zizanioides essential oil on melanogenesis in melanoma cells: downregulation of tyrosinase expression and suppression of oxidative stress.

The major objective of this study was to estimate the hypopigmentation function of the essential oil from Vetiveria zizanioides (VZ-EO). Our results indicated that VZ-EO exhibits potent lipid peroxidation inhibitory activity to moderate the bleaching of ß-carotene and to maintain the cellular glutathione (GSH) levels. VZ-EO can markedly decrease melanin production and tyrosinase activity in α-melanin-stimulating-hormone- (α-MSH-) stimulated B16 cells. The effect of VZ-EO on melanogenesis is achieved by the suppression of cellular tyrosinase expression. The results demonstrated that the activity of VZ-EO on melanogenesis might be the result of its potent antioxidative ability, which was reflected in the decreased cellular oxidant and malondialdehyde (MDA) levels and the recovered activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) in α-MSH-stimulated B16 cells. The most abundant compound in VZ-EO is cedr-8-en-13-ol (12.4%), which has a strong capability to inhibit lipid peroxidation. Therefore, VZ-EO has the potential to become an ingredient in future hypopigmentation drugs, foods, and cosmetics.