TY - JOUR
T1 - The relation between canine cognitive dysfunction and age-related brain lesions
AU - Ozawa, Makiko
AU - Chambers, James K.
AU - Uchida, Kazuyuki
AU - Nakayama, Hiroyuki
N1 - Publisher Copyright:
© 2016 The Japanese Society of Veterinary Science.
PY - 2016/6/1
Y1 - 2016/6/1
N2 - Canine cognitive dysfunction (CCD) is a syndrome that manifests itself in abnormal behaviors, such as disorientation and wandering. β-amyloid deposition in the brain, including the senile plaque (SP) and cerebral amyloid angiopathy (CAA), has been suggested as a major cause of the syndrome. However, the pathological significance of β-amyloid deposition in CCD dogs remains unclear. The present study was conducted using 16 dogs aged 10 years or older to clarify the relationship between the age-related histopathological lesions, such as β-amyloid deposition, in the brain and the clinical symptoms of CCD as evaluated in a questionnaire previously established in a large survey. In addition, age-related brain lesions were assessed in 37 dogs. The pathological lesions were evaluated by the severity of β-amyloid deposition (SP and CAA), the amount of ubiquitin-positive granules (UBQ), GFAP-positive astrocytes, Iba-1-positive microglia and Nissle stain-positive nerve cells. The results revealed that there was no significant correlation between the severities of canine SP and CCD. The SP increased until 14 years old, but decreased thereafter, although the incidence of CCD is high at these ages. The CAA consistently increased with age, but did not correlate greatly with the CCD score. In contrast, the increases of UBQ, astrocytes and microglia were significantly correlated with CCD. Thus, the impairment in the synapse and/or myelin suggested by increased UBQ and glial activation might be involved in CCD pathogenesis, but β-amyloid deposition, especially SP, is not a direct pathogenic factor of CCD.
AB - Canine cognitive dysfunction (CCD) is a syndrome that manifests itself in abnormal behaviors, such as disorientation and wandering. β-amyloid deposition in the brain, including the senile plaque (SP) and cerebral amyloid angiopathy (CAA), has been suggested as a major cause of the syndrome. However, the pathological significance of β-amyloid deposition in CCD dogs remains unclear. The present study was conducted using 16 dogs aged 10 years or older to clarify the relationship between the age-related histopathological lesions, such as β-amyloid deposition, in the brain and the clinical symptoms of CCD as evaluated in a questionnaire previously established in a large survey. In addition, age-related brain lesions were assessed in 37 dogs. The pathological lesions were evaluated by the severity of β-amyloid deposition (SP and CAA), the amount of ubiquitin-positive granules (UBQ), GFAP-positive astrocytes, Iba-1-positive microglia and Nissle stain-positive nerve cells. The results revealed that there was no significant correlation between the severities of canine SP and CCD. The SP increased until 14 years old, but decreased thereafter, although the incidence of CCD is high at these ages. The CAA consistently increased with age, but did not correlate greatly with the CCD score. In contrast, the increases of UBQ, astrocytes and microglia were significantly correlated with CCD. Thus, the impairment in the synapse and/or myelin suggested by increased UBQ and glial activation might be involved in CCD pathogenesis, but β-amyloid deposition, especially SP, is not a direct pathogenic factor of CCD.
KW - Aging
KW - Beta amyloid
KW - Canine cognitive dysfunction
UR - http://www.scopus.com/inward/record.url?scp=85011082312&partnerID=8YFLogxK
U2 - 10.1292/jvms.15-0624
DO - 10.1292/jvms.15-0624
M3 - Article
C2 - 26922972
AN - SCOPUS:85011082312
SN - 0916-7250
VL - 78
SP - 997
EP - 1006
JO - Journal of Veterinary Medical Science
JF - Journal of Veterinary Medical Science
IS - 6
ER -