Neurotoxic effects of biological fluids of Alzheimer's disease patients' on cerebellar granule cell cultures

Abstract

Aim: Alzheimer’s disease (AD) is the most common form of dementia that affects millions people worldwide. Molecular mechanisms of Alzheimer's disease as well as biomarkers for early diagnostics are unclear. The aim of this study was to investigate effects of patients' biological fluids on primary cerebellar granule cell cultures (CGC). Methods: Primary mixed neuronal-glial cultures from rat cerebella (CGC) were prepared from 7-8 days old Wistar rats. Blood serum and cerebrospinal fluid (CSF) were donated by healthy, age-matched individuals (with zero degree of dementia; control group) and patients with Alzheimer's disease (diagnosed with Alzheimer's type dementia DAT). CGCs were incubated with serum and CSF for 24 hours. The viability of neurons in cultures was assessed by fluorescence microscopy. Results: We found that neither control or patients' sera had any effect on viability of neurons and glial cells. CSF from control group did not affect neuronal viability while patients‘ CSF reduced neuronal viability by about 20%. CSF from both groups had no effect on viability of glial cells. Interestgly, patients‘ CSFs significantly reduced density of neurons in CGC cultures, while control CSF had no effect on neuronal density. Patients‘ CSF also stimulated microglial proliferation, whereas control CSF (and control and patients sera) had no effect on microglial proliferation. Conclusions: our study revealed that CSF from patients with Alzheimer's disease but not healthy subjects exhibit neurotoxic effects on CGCs cultures. This can be used as a basis for development of diagnostic methods for early diagnostics of Alzheimer‘s disease.