title: Chitooligosaccharides protect cultured hippocampal neurons against glutamate-induced neurotoxicity.
abstract: Chitooligosaccharides (COSs), the biodegradation product of chitosan, have demonstrated a diverse array of biological activities. Here we report the protective effect of COSs (M.W. 800) against glutamate-induced neurotoxicity in cultured hippocampal neurons. The cell viability assessments, together with Hoechst 33342 staining and flow cytometry for cell apoptosis analysis, indicated that glutamate (125 microM)-induced cell apoptosis in cultured hippocampal neurons was attenuated in a concentration-dependent manner by COSs pretreatment. After measurement with Fluo 4-AM, COSs were found to depress glutamate-induced elevation in intracellular calcium concentration ([Ca(2+)](c)). The enzymatic assay indicated that COSs antagonized glutamate-evoked activation of caspase-3. These results collectively suggest that COSs prevent cultured hippocampal neurons from glutamate-induced cell damage by interfering with an increase in [Ca(2+)](c) and inhibiting caspase-3 activity.
authors.affiliation: Jiangsu Key Laboratory of Neuroregeneration, Nantong University, 19 Qixiu Road, Nantong, JS 226001, PR China.
authors.forename: Songlin
authors.initials: S
authors.lastname: Zhou
authors.forename: Yumin
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Gu
authors.forename: Fei
authors.initials: F
authors.lastname: Ding