Programmed cell death in neurodegenerative brain disease

Abstract

Death of brain cells by either apoptosis or necrosis is the hall mark of the pathology of most brain infections such as Alzheimer’s disease and AIDS dementia. The death of astrocytes in association with brain tumours appears to be an insignificant event. Detection of apoptosis in human brain tissues fixed in 10% buffered formalin and embedded in paraffin wax was determined in the Department of Medicine, in conjunction with the Department of Dermatology, University of Wales College of Medicine using three selected methods, namely Heamatoxylin and Eosin (H and E) which intensely stains the nuclei of apoptotic cells dark, Methyl Green Pyronin (MGP) which stains the nuclei of apoptotic cells deep pink purple and terminal deoxynucleotidyl tranferase uridine nick end labeling (TUNEL) method which stains the DNA fragments of apoptotic cells dark brown. By looking at changes in the cell nuclei, together with mRNA levels in the cytoplasm and also by analyzing DNA fragments in situ, evidence of apoptosis was found both in neurons and astrocytes. The type and number of brain cells that died from apoptosis varied from case to case. Apoptosis was not detected in normal aging brain control.