Platelet MAO-B activity and vitamin B12 in old age dementias

Abstract

Platelet MAO-B activity, serum vitamin B12 levels, and plasma folate were measured in patients suffering from presenile (AD) and senile (SDAT) dementia of Alzheimer-type, and vascular dementia (VD). MAO-B was higher in the SDAT group than in AD and controls. An inverse relationship between MAO-B activity and vit. B12 levels was documented in the whole group and in each category studied; furthermore, MAO-B was positively related to age. All the patients were then divided into two groups, according to vit. B12 levels (Group I: less than 200 pg/mL; Group II: greater than or equal to 200 pg/mL); Group I showed a significantly higher MAO-B activity with respect to Group II. The results indicate the existence of a negative association between platelet MAO-B activity and serum levels of vitamin B12 and confirm the existence of biological differences between presenile and senile dementia of Alzheimer type.

Glycosaminoglycan Polysulfate in Primary Degenerative Dementia

“…For platelet M A O -B activity determination, the method devel oped by Eckert et al [ 17] partially modified by Pametti et al [ 18] was employed. First, 8 ml o f blood was suspended in an cthylenediaminetetra-acetic acid solution; then platelets were isolated by three con secutive centrifugations for 5 min at 200 g and by one last centrifuga tion for 15 min at 200 g. Finally, after a wash with saline solution platelets were kept at -85 °C until the performance o f the assay.…”