Fibrinogen α-chain amyloidosis is a hereditary disease in humans in which the fibrinogen α-chain involved in blood coagulation forms amyloid and deposits in the glomeruli of the kidney, leading to renal failure.There is no definitive treatment because the number of patients worldwide is small and the mechanism of the disease remains unclear.Therefore, it is desired to develop a treatment method based on accurate understanding of pathological conditions.Although animal studies may help humans, the disease has not been found in animals other than humans.

　This time, the research team conducted a histopathological analysis of the systemic organs of a total of 38 Japanese squirrels that died in domestic zoos. We found that 29 patients (76.3%) had systemic amyloidosis characterized by amyloid deposits in the renal glomeruli, and identified fibrinogen α-chain as the causative protein of amyloid.

　A detailed investigation ruled out a genetic predisposition as an onset factor in the Japanese squirrel.In addition, the prevalence of amyloidosis in elderly Japanese squirrel individuals was about 9%, and statistical analysis showed a significant relationship between aging and the onset of amyloidosis.Based on this, we conclude that fibrinogen α-chain amyloidosis in Japanese squirrels is an age-related disease inherent to this species.

　By elucidating in detail why the fibrinogen α chain in Japanese squirrels tends to form amyloid, it is expected that this will contribute to the elucidation of pathologies that will lead to the maintenance of the health of Japanese squirrels and the development of treatments for humans.

Paper information:[The Journal of Pathology] Fibrinogen Aα-chain amyloidosis outbreaks in Japanese squirrels (Sciurus lis): a potential disease model