TY - JOUR
T1 - Presenilin-1 regulates the neuronal threshold to excitotoxicity both physiologically and pathologically
AU - Grilli, M.
AU - Diodato, E.
AU - Lozza, G.
AU - Brusa, R.
AU - Casarini, M.
AU - Uberti, D.
AU - Rozmahel, R.
AU - Westaway, D.
AU - St. George-Hyslop, P.
AU - Memo, M.
AU - Ongini, E.
PY - 2000/11/7
Y1 - 2000/11/7
N2 - A direct pathophysiological role of Familial Alzheimer's Disease (FAD)-associated Presenilin 1 (PS1) mutations in neuronal vulnerability remains a controversial matter. We evaluated the relationship between PS1 and excitotoxicity in four different experimental models of neurotoxicity by using primary neurons from (i) transgenic (tg) mice overexpressing a human FAD-linked P51 variant (L286V mutation), (ii) tg mice overexpressing human wild-type (wt) P51, (iii) PS1 knockout mice, and (iv) wt mice in which PS1 gene expression was knocked down by antisense treatment. We found that primary neurons overexpressing mutated P51 showed an increased vulnerability to both excitotoxic and hypoxic-hypoglycemic damage when compared with neurons obtained from either mice overexpressing human wt P51 or in wt mice. In addition, reduced excitotoxic damage was obtained in neurons in which PS1 expression was absent or diminished. Data obtained in in vivo experimental models of excitotoxicity partially supported the in vitro observations. Accelerated neuronal death was demonstrated in the hippocampus of mice overexpressing mutated PS1 after peripheral administration of kainic acid in comparison with wt animals. However, measurement of the infarct volume after middle cerebral artery occlusion did not show significant difference between the two animal groups. The results altogether suggest that expression of FAD-linked PS1 variants increases the vulnerability of neurons to a specific type of damage in which excitotoxicity plays a relevant role. In addition, they support the view that reduction of endogenous PS1 expression results in neuroprotection.
AB - A direct pathophysiological role of Familial Alzheimer's Disease (FAD)-associated Presenilin 1 (PS1) mutations in neuronal vulnerability remains a controversial matter. We evaluated the relationship between PS1 and excitotoxicity in four different experimental models of neurotoxicity by using primary neurons from (i) transgenic (tg) mice overexpressing a human FAD-linked P51 variant (L286V mutation), (ii) tg mice overexpressing human wild-type (wt) P51, (iii) PS1 knockout mice, and (iv) wt mice in which PS1 gene expression was knocked down by antisense treatment. We found that primary neurons overexpressing mutated P51 showed an increased vulnerability to both excitotoxic and hypoxic-hypoglycemic damage when compared with neurons obtained from either mice overexpressing human wt P51 or in wt mice. In addition, reduced excitotoxic damage was obtained in neurons in which PS1 expression was absent or diminished. Data obtained in in vivo experimental models of excitotoxicity partially supported the in vitro observations. Accelerated neuronal death was demonstrated in the hippocampus of mice overexpressing mutated PS1 after peripheral administration of kainic acid in comparison with wt animals. However, measurement of the infarct volume after middle cerebral artery occlusion did not show significant difference between the two animal groups. The results altogether suggest that expression of FAD-linked PS1 variants increases the vulnerability of neurons to a specific type of damage in which excitotoxicity plays a relevant role. In addition, they support the view that reduction of endogenous PS1 expression results in neuroprotection.
UR - http://www.scopus.com/inward/record.url?scp=12944305721&partnerID=8YFLogxK
U2 - 10.1073/pnas.97.23.12822
DO - 10.1073/pnas.97.23.12822
M3 - Article
SN - 0027-8424
VL - 97
SP - 12822
EP - 12827
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 23
ER -