It was found that the main component of amyloid plaque in the brain, which is a characteristic of Alzheimer-type dementia, is taken up into the brain by infection with gingivalis (Pg), which is a typical causative bacterium of periodontal disease.It was revealed in a joint research between Kyushu University and Beijing Institute of Technology, China.
This group, which is working to elucidate the mechanism of periodontal disease's involvement in Alzheimer's disease, has so far produced amyloid β (Aβ), which is the main component of amyloid plaque in the brain, in inflammatory tissues such as gums due to Pg infection. Has been clarified to induce.Accumulation of Aβ is present in and around the cerebrovascular disease in more than 80% of Alzheimer-type dementia, and the accumulation of Aβ in the brain is considered to be one of the causes of Alzheimer-type dementia.This time, a mechanism was found in which Aβ produced systemically by Pg infection is imported into the brain to promote the accumulation of Aβ in the brain.
When Pg bacteria were administered to mice for 3 consecutive weeks, the researchers developed advanced glycation end product receptor RAGE, which is responsible for the intracerebral transport of Aβ in the cerebrovascular disease, and Aβ was generated in the brain parenchyma around the cerebrovascular disease. It was found that it increased locally and induced memory impairment.As a result of investigating this mechanism using functional model cells of the human blood-brain barrier, RAGE expression is enhanced by the action of cathepsin B, which is increased by Pg infection, and the influx of Aβ into the blood-brain barrier is increased. It turned out that.
A radical cure for Alzheimer's disease has not yet been established, and measures to delay its onset and progression are urgent issues.Since this study revealed that cathepsin B-dependent RAGE expression promotes Aβ accumulation in the brain, the development of cathepsin B inhibitors may be effective as "preemptive medicine" for Alzheimer's disease. There is.
In addition, the results of this study reiterate that oral care, including the prevention of periodontal disease, leads to the prevention of Alzheimer-type dementia.
