Aluminum (Al) accumulation increases with
aging , and long-term exposure to Al is regarded as a
risk factor for
Alzheimer's disease . In this study, we investigated the effects of Al and/or
D-galactose on
neural stem cells , proliferating
cells , differentiating neuroblasts, and mature
neurons in the hippocampal
dentate gyrus .
AlCl3 (40 mg/kg/day) was intraperitoneally administered to C57BL/6J
mice for 4 weeks. In addition, vehicle (physiological saline) or
D-galactose (100 mg/kg) was subcutaneously injected to these
mice immediately after
AlCl3 treatment .
Neural stem cells , proliferating
cells , differentiating neuroblasts, and mature
neurons were detected using the relevant marker for each
cell type, including
nestin , Ki67, doublecortin, and NeuN, respectively, via
immunohistochemistry . Subchronic (4 weeks) exposure to Al in
mice reduced
neural stem cells , proliferating
cells , and differentiating neuroblasts without causing any changes to mature
neurons . This Al-induced reduction effect was exacerbated in
D-galactose -treated
mice compared to vehicle-treated
adult mice . Moreover, exposure to Al enhanced
lipid peroxidation in the
hippocampus and expression of
antioxidants such as Cu, Zn- and
Mn-superoxide dismutase in
D-galactose -treated
mice . These results suggest that Al accelerates the reduction of
neural stem cells , proliferating
cells , and differentiating neuroblasts in
D-galactose -treated
mice via
oxidative stress , without inducing loss in mature
neurons .