Hippocampal neuronal loss in aged dogs

This study aimed to quantify the total number of neuronal and non-neuronal cells in the hippocampus of aged dogs using the isotropic fractionator method. For this purpose, an analysis was conducted on 17 animals, eight males and nine females, 12 mixed-breed, and one specimen of each of the following breeds: Yorkshire, Poodle, Boxer, Dachshund, and British Bulldog. There were nine small-sized dogs, seven medium-sized dogs, and one big-sized dog. Presenting an average weight of 12,88 kilograms. The average age was 14 years old. The presence of β-amyloid deposits was detected in nine of the dogs, of those, four presented signs of cognitive impairment. There were eight negative dogs for the presence of β-amyloid deposits, none of them presented signs of cognitive impairment. Cell quantification demonstrated a significant correlation with age, indicating a progressive decrease in the number of neurons and an increase in the non-neuronal cell count with the age progression. Therefore, cell counting may be a relevant indicator to understand the alterations associated with canine aging and help elucidate the pathological processes and mechanisms of age-related neurodegenerative diseases.