Effects of ultrasound and selenium on human neurons in vitro

As the effects of ultrasound on human brain functions might bear therapeutic potential, in this study, we examined the effects of diagnostic, i.e. non-thermal, ultrasound, on morphology, networking, and metabolic activity of SH- SY5Y human neurons in culture, as well as on the expression of GAP-43, Hsp90 and VEGF proteins, with and without selenium in the culture medium. The rationale for studying selenium lays in the observation that selenium improves functional neurologic outcome in traumatic brain injury and, therefore, analysis of the interactions between ultrasound and selenium may be of clinical interest. In the presence of selenium, ultrasound increased the overall number and length of elongations arising from the neuron bodies, thus reflecting an increase in the complexity of neuronal networks and circuits. The expression of GAP-43, Hsp90 and VEGF and metabolic activity of SH-SY5Y neurons, studied as markers of cell damage, were not affected by ultrasound or selenium. This study suggests that ultrasound may modulate neuronal networking in vitro without inducing cellular or molecular damage and highlights the potential role of selenium in the ultrasound-elicited cellular responses.

Evidence of immunocompetence reduction induced by cadmium exposure in honey bees (Apis mellifera)

In the last decades a dramatic loss of Apis mellifera hives has been reported in both Europe and USA. Research in this field is oriented towards identifying a synergy of contributing factors, i.e. pathogens, pesticides, habitat loss and pollution to the weakening of the hive. Cadmium (Cd) is a hazardous anthropogenic pollutant whose effects are proving to be increasingly lethal. Among the multiple damages related to Cd contamination, some studies report that it causes immunosuppression in various animal species. The aim of this paper is to determine whether contamination by Cd, may have a similar effect on the honey bees' immunocompetence. Our results, obtained by immune challenge experiments and confirmed by structural and ultrastructural observations show that such metal causes a reduction in immunocompetence in 3 days Cd exposed bees. As further evidence of honey bee response to Cd treatment, Energy Dispersive X-ray Spectroscopy (X-EDS) has revealed the presence of zinc (Zn) in peculiar electron-dense granules in fat body cells. Zn is a characteristic component of metallothioneins (MTs), which are usually synthesized as anti-oxidant and scavenger tools against Cd contamination. Our findings suggest that honey bee colonies may have a weakened immune system in Cd polluted areas, resulting in a decreased ability in dealing with pathogens.