The research group of Assistant Professor Ayako Tonojo and Professor Motoyuki Ito of Chiba University Graduate School of Pharmaceutical Sciences revealed that insulin and insulin-dependent signals in adipocytes are required for memory maintenance.In addition, since the amount of insulin changes with aging, it is expected to be useful for elucidating the cause of age-related memory decline.
Insulin, which regulates blood glucose levels and regulates metabolism, binds to insulin receptors on the cell membrane and signals intracellularly, and plays an important role in various timings and tissues such as regulation of development, growth, and metabolism. ..However, it was unclear how insulin was involved in learning, memory, and even age-related memory decline.
This time, we created Drosophila that transiently suppressed insulin signals without affecting the time of development and growth, and measured their learning and memory abilities.Insulin signals were found to be required for memory maintenance.Insulin receptors are also expressed in various tissues, but it was found that expression in adipose tissue is particularly necessary for memory maintenance.
In addition, in Drosophila, the functions of insulin and insulin-like growth factor (IGF), which is very similar to insulin, are shared by eight types of Dilp (insulin-like peptide: Dilp8-1).In this study, Dilp8 is important for memory, and in young Drosophila, memory is maintained by activation of insulin signals in Dilp3 and adipose tissue, whereas in aged Drosophila, decreased expression of Dilp3 causes memory decline. Became clear.
This time, it was suggested that age-related changes in insulin signals contributed to memory decline.In the future, it is expected to be useful for elucidating the mechanism of learning and memory, elucidating the cause of age-related memory decline, and treating dementia.
