Sulfated Polysaccharide Isolated from the Sea Cucumber Stichopus japonicus Promotes Neurosphere Migration and Differentiation via Up-regulation of N-Cadherin

In this report, the sulfated polysaccharide (SJP) from the body wall of the sea cucumber Stichopus japonicas was extracted and tested for its capacity to affect migration and differentiation of neural stem/progenitor cells. SJP is an intensely sulfated polysaccharide with a molecular weight of 1.79 x 10(5) Da that is capable of promoting neurosphere attachment and migration in a dose-dependent manner. Moreover, SJP effectively maintains cell viability even after being deprived of mitogens. Our current results demonstrate that neurosphere are differentiated into neuronal and glial cells when exposed to SJP. These effects were accompanied by an up-regulation of the adhesion molecule, N-cadherin. In addition, we observed that blocking of PI3K activity inhibited N-cadherin-mediated activity. This SJP-induced up-regulation of N-cadherin mediates neurosphere adhesion migration and differentiation via the PI3K/Akt signaling pathway. These results suggest that SJP could be used as a therapeutic agent to mobilize neuroblast migration under conditions of brain injury and disease.