BACKGROUND: L-3-n-butylphthalide (L-NBP) can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 (A beta(1-42)). OBJECTIVE: To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B (NF-kappa B) expression in a rat model of Alzheimer's disease. DESIGN, TIME AND SETTING: A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS: L-NBP (purity > 98%) was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. A beta(1-42), 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide (MTT), and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF-kappa B antibodies were provided by Santa Cruz, USA. METHODS: Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups: the control group, the A beta(1-42) group (2 mu mol/L), the A beta(1-42) + 0.1 mu mol/L L-NBP group, the A beta(1-42) + 1 mu mol/L L-NBP group, and the A beta(1-42) + 10 mu mol/L L-NBP group. The neurons were treated with A beta(1-42) (2 mu mol/L) alone or in combination with L-NBP (0.1, 1, 10 mu mol/L) for 48 hours. Cells in the control group incubated in PBS. were MAIN OUTCOME MEASURES: Morphologic changes were evaluated using inverted microscopy, viability using the MTT method, and the changes in caspase-3 and NF-kappa B expression using Western blot. RESULTS: Induction with A beta(1-42) for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF-kappa B expression (P < 0.05). L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF-kappa B expression (P < 0.05), and improved cell viability, especially at the high dose (P < 0.05). CONCLUSION. A beta(1-42) is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF-kappa B expression.
