engleski

Peripheral biochemical markers in Alzheimer's disease

Alzheimer's disease (AD) is a multifactorial and complex disorder. The age of the onset and the course of AD could be related to the lifestyle, genetic, socidemographic, environmental, clinical and pharmacological factors. Post mortem brain studies indicated that the alterations in neurotransmitters systems could be involved in the ethiology of AD. The aim of the study was to determine peripheral biochemical markers (platelet serotonin/5- HT/ concentration, platelet monoamine oxidase type B /MAO/ and plasma dopamine-beta hydroxylase /DBH/ activity) in patients with AD subdivided according to the onset of disease and to the presence of psychotic features. The diagnosis of the probable AD fulfilling NINCDS- ADRDA criteria was established according to the ICD-10 and DSM-IV-TR criteria. Mini Mental Status Examination (MMSE) was used to assess the cognitive impairment. The study included 43 male and 144 female patients with AD subdivided in two groups according to early (before the age of 64 years) or late (after the age of 65 years) onset of AD. The control group consisted of sex and age- matched drug free healthy subjects (65 female and 51 male) with no history of the psychiatric illness. Platelet 5-HT concentration and platelet MAO activity were determined using spectrofluorimetric methods, and plasma DBH using photometric method. The platelet MAO activity was higher in female patients with early and late and male patients with early onset of AD as compared to healthy controls. The pronounced increased in platelet MAO activity was observed in AD patients with nonpsychotic features. Plasma DBH activity was significantly lower in patients with AD. There were no significant difference in platelet 5-HT concentrations among groups. The ethiology and progress of AD could be connected with the changes in the biochemical parameters. The results of this ongoing study, support the presumption that platelet MAO and plasma DBH activity could be used as a biological marker for different categories of AD. Our results of the altered MAO and DBH activity in patients with AD, support the presumption that toxic and reactive metabolites of catecholamine neurotransmitters could be involved in the ethiology of AD.

Alzheimer's disease; platelet serotonin; platelet monoamine oxidase type B; plasma dopamine-beta hydroxylase

Indexed / Abstracted in: Neuroscience Citation Index ; EMBASE / Excerpta Medica