Controlled activity of mouse astrocytes on electrospun PCL nanofiber containing polysaccharides from brown seaweed.

The central nervous system (CNS), once injured, rarely recovers original function mainly due to its limited regeneration ability. Astrocytes are cells that play critical roles in neural regeneration. Several biomaterials have been studied to replace and regenerate lost tissues within injured CNS. Seaweeds have extracellular polymeric substances (EPS) with bioactive properties such as antiviral and antioxidant properties. In this study, astrocyte activity was assessed, after being cultured on an electrospun polycaprolactone (PCL) nanofibrous mat containing a brown seaweed EPS. Laminarin and fucoidan, two main components of EPS extract from the brown seaweed, were concluded to increase or decrease astrocyte activity with respect to their concentration. When the concentration was under 10 μg/ml, the astrocytes tended to increase their viability. In contrast, over 10 μg/ml EPS in media suppressed the viability of astrocytes. In addition, when contained in PCL nanofiber, the EPS extract was also proven to influence astrocyte activity in the same way as the case when astrocytes were exposed to EPS in solution. This implies that the brown seaweed EPS-PCL nanofiber mat can be used for temporal control of astrocyte activity by EPS concentration. Through this research, we propose that the electrospun EPS-PCL nanofiber could be used as a nanomedicine or scaffold to treat CNS injuries.