Cytoplasmic gelsolin in pheochromocytoma-12 cells forms a complex with amyloid β-protein

Gelsolin exists as secretory (plasma) and cytoplasmic forms. We have reported that plasma gelsolin binds to annyloid beta-protein (Aft and inhibits its fibrillization. Others reported that peripheral administration or transgene expression of plasma gelsolin reduces amyloid load in transgenic mouse models of Alzheimer's disease. Here, we report that the expression of cytoplasmic gelsolin in pheochromocytoma-12 cells increases after treatment with hydrogen peroxide. When synthetic A beta was fortified with cell lysate, cytoplasmic gelsolin co-immunoprecipitated with A beta. The results suggest that cytoplasmic gelsolin forms a complex with A beta in a manner like plasma form, and it may also regulate A beta fibrillization. This report indicates that structural differences between plasma and cytoplasmic gelsolin do not play a key role in their complex formation with A beta.