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Carlos Fernández-Moriano et al.
(Ps) are probably due to the presence of alectoronic acid Finally, it can be stated that tested lichen species
and protocetraric acid, respectively; both extracts contain display promising neuroprotective properties, based on
atranorin as another secondary metabolite in an importance their antioxidative effects, in nervous system cellular
proportion, so atranorin should also be taken into model of excessive oxidative stress. Results suggest that
consideration when dealing with pharmacological the three species could be an interesting source of natural
properties. Regarding Usnea ghattensis methanol extract products with neuroprotective interest; deeper
(Ug), usnic acid is present in similar concentration than investigations may focus on the study of effects of isolated
other compounds belonging to the stictic acid complex metabolites in other in vitro and in vivo models of
(consictic and stictic acid), and those metabolites could neurodegeneration.
also contribute to the biological activities; then,
antioxidant capacity should not be only attributed to usnic 6. CONFLICT OF INTERESTS
acid in this specie.
The authors declare that there is no conflict of interests.
5. CONCLUSIONS
7. ACKNOWLEDGMENTS
Methanol extracts of Cetrelia braunsiana, Parmotrema
saccatilobum and Usnea ghattensis have been investigated This work was supported by a doctoral grant from the
for the first time regarding their neuroprotective activities, Spanish Ministry of Education, Culture and Sports (FPU),
via antioxidant actions, in a model of oxidative stress in awarded to Carlos Fernandez Moriano (N° FPU12/03824).
nervous system-like cells (neuron model); for such
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@Real Academia Nacional de Farmacia. Spain
