The Ministry of Science, ICT & Future Planning announced on March 14 that Seoul National University professor Mook In-hee and her research team succeeded in clarifying the mechanism of the secretion of the insulin-degrading enzyme (IDE) degrading insulin and beta amyloid at the same time, which is critical for dealing with Alzheimer's disease.
Alzheimer's disease is caused by an abnormal degradation of beta amyloid. Beta amyloid is accumulated in the brains of the people suffering from the disease. The IDE, an enzyme degrading it in the human body, contributes to the removal of insulin, too. Although it has been found that astrocytes, which take up most of the human brain, constitute a main agent of IDE generation, the mechanism of IDE secretion from astrocytes had yet to be found out.
The research team treated astrocytes with beta amyloid at this time and confirmed an increase in IDE secretion from the cells. In addition, it discovered that the autophagy of astrocytes and lysosome flow have to do with IDE secretion.
Specifically, the team injected beta amyloid into the brains of lab mice where the genes of Atg7, which are important for autophagy, are present in half and in full, and then compared the amounts of IDEs in the cerebrospinal fluids to reach a conclusion that the lab mice with malfunctions in autophagy have a reduced IDE amount.
“Our research outcome is expected to contribute to the development of a medicine that can promote the degradation of beta amyloid for the treatment of Alzheimer's disease,” the professor explained. Details of the research are available on the March 15 edition of the online version of Autophagy.