A marine-derived acidic oligosaccharide sugar chain specifically inhibits neuronal cell injury mediated by beta-amyloid-induced astrocyte activation in vitro.

In Alzheimer's disease (AD), beta-amyloid (Abeta) plaques are surrounded by activated astrocytes and microglia. A growing body of evidence suggests that these activated astrocytes contribute to neurotoxicity through the induction of inflammatory cytokines and the production of oxidative stress mediators. Thus, a compound inhibiting Abeta-induced activation of astrocytes may lead to a novel therapy for AD. Our current work investigates the roles of acidic oligosaccharide sugar chain (AOSC), derived from brown algae Echlonia Kurome Okam, on Abeta-induced inflammatory responses and cytotoxicity. We observed that AOSC inhibited the toxicity and apoptosis in SH-SY5Y cell line induced by Abeta-stimulated astrocytes conditioned medium. We found that AOSC inhibited the reactive phenotype of astrocytes, blocked cellular oxidative stress, reduced the production of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 and prevented the influx of Ca2+. Thus, our results indicate that AOSC might be a potentially therapeutic compound for AD.